The CSQUARE Transform
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Landscape Design Proposal for the Square IntroductionThe aim of this proposal is to present a comprehensive landscape design plan for the square. The design takes into consideration the aesthetic and functional aspects of the space while also incorporating elements of sustainability and environmental consciousness.Design ConceptThe design concept for the square focuses on creating a harmonious and inviting space that caters to the needs of both residents and visitors. The key elements of the design concept include:1.Green Spaces: The square will feature expansive green spaces with avariety of trees, plants, and flowers. These green areas will provide shade,improve air quality, and create a soothing environment for the community.2.Seating Areas: Comfortable seating areas will be strategically placedthroughout the square to encourage social interaction and relaxation. Theseating will be made of durable and sustainable materials, such as recycledplastic or bamboo.3.Water Features: The design will incorporate water features, such asfountains or small ponds, to add a sense of tranquility and enhance theaesthetics of the square. The water features will also serve as natural cooling elements during hot summer months.4.Lighting: Proper lighting will be installed to ensure safety and createa welcoming ambiance in the square. The lighting fixtures will be energy-efficient LED lights that minimize energy consumption and reduce lightpollution.5.Art Installations: Art installations will be strategically placedthroughout the square to add visual interest and cultural significance. These installations can include sculptures, murals, or interactive artworks that engage the community and create a sense of identity for the space.Sustainability MeasuresIn order to promote sustainability and reduce the environmental impact of the square, the following measures will be implemented:1.Rainwater Harvesting: The square will be equipped with a rainwaterharvesting system to collect and reuse rainwater for irrigation purposes. Thissystem will help conserve water resources and reduce dependence onmunicipal water supply.2.Native Plant Selection: The landscape design will prioritize the useof native plant species, which are adapted to the local climate and require less water and maintenance. This approach will also enhance biodiversity andsupport the local ecosystem.3.Permeable Pavement: Permeable pavement materials will be used inselect areas of the square to allow rainwater to soak into the ground instead of contributing to stormwater runoff. This will help recharge the groundwater and minimize flooding risks.4.Solar-powered Lighting: Where feasible, solar-powered lightingfixtures will be used to further reduce energy consumption and reliance on the electrical grid. These fixtures will rely on renewable solar energy to illuminate the square during nighttime hours.Implementation PlanThe implementation of the landscape design will be carried out in the following phases:1.Site Preparation: The square will be cleared of any existingstructures or obstacles to create a blank canvas for the landscape design. The soil will be tested and assessed for its suitability for plant growth.2.Infrastructure Development: The required infrastructure, such asirrigation systems, seating installation, and lighting fixtures, will be put in place.This will require coordination with relevant contractors and suppliers.3.Plantation and Hardscaping: The planting of trees, shrubs, flowers,and installation of hardscaping features, such as paths and seating areas, will take place during this phase. Native plant species will be sourced from localnurseries.4.Art Installations: The selected art installations will be commissionedor acquired from artists and installed in designated areas as specified in thedesign plan.5.Final Touches: The finishing touches will be added, including theinstallation of signage, establishing maintenance protocols, and conducting a final inspection to ensure everything is in place before the square is officially open to the public.Maintenance and ManagementOnce the square is completed, a maintenance and management plan will be implemented to ensure its upkeep and longevity. This plan will include regular maintenance activities, such as landscaping, cleaning, and inspection of infrastructure. Additionally, community engagement programs will be organized to promote a sense of ownership and encourage the public to take pride in the square.ConclusionThe landscape design proposal presented in this document aims to transform the square into an aesthetically pleasing, sustainable, and community-centric space. By incorporating green spaces, seating areas, water features, art installations, and sustainable measures, the square will become a vibrant and inviting destination for residents and visitors alike.。
上海外滩英文导游词_外滩英语导游词外滩是上海的标志,许多游客去上海游玩都会去那里参观,导游带领各国各地的游客时,要用中英文做好解说。
下面是带来的上海外滩英文导游词,仅供大家参考。
上海外滩英文导游词篇一游客朋友你们好!Tourists friend you are good!现在我们来到上海黄浦江畔的外滩,首先,我对各位的参观游览外滩表示欢迎,并预祝各位旅游愉快。
Now we came to Shanghai bund across the huangpu river, first of all, I to your visit welcomed the bund, and wish every travel time.新外滩共有五条旅游路线,在您的左手边是被誉为“万国建筑博览”的壮观建筑群和宽敞的中山路,您的右手边是波光粼粼的黄浦江以及前程似锦的浦东陆家点缀金融贸易区,眼前为新颖独特的观光游览区。
这建筑群、中山路、观光区、黄浦江、陆家嘴仿佛乐谱中的五线谱,勤劳上海人民则好似串串间符,正组成最新最华美的乐章,欢迎着各位来宾的光临。
New bund article were five travel route, on your left is known as the "all nations building expo" grand buildings and spacious zhongshan road, your right hand side is the 1/ 23shimmering huangpu river and the beautiful pudong lujiaornament financial and trade zone, the eyes for novel and unique tourism recreational area. This complex, zhongshan road, sightseeing area, the huangpu river, as if the music lujiazui, Shanghai people are industrious staff like clusters of operators, is between the latest and most colorful movement, welcome to the guests.外滩它过去曾是上海老城厢外的一块芦苇丛生的荒滩地。
完整版)初三数学总复习知识点Chapter 1: Quadratic Radical1.A quadratic radical is an n of the form a (a≥0).Property: a (a≥0) is a non-negative number;a^2=a (a≥0);a^2=a (a≥0).2.n and n of quadratic radicals: a•b=ab (a≥0.b≥0);a/a (a≥0.b>0)=√a/b.3.n and n of quadratic radicals: when adding or subtracting quadratic radicals。
XXX form first。
then combine the quadratic radicals with the same radicand.4.Heron's formula: S=p(p-a)(p-b)(p-c)。
where S is the area ofa triangle。
and p=(a+b+c)/2.Chapter 2: XXX1.XXX that has only one unknown variable。
and the highest degree of the variable is2.2.XXX:Completing the square method: transform one side of the ninto a perfect square。
then take the square root of both sides;Quadratic formula: x=(-b±√(b^2-4ac))/2a;Factoring method: factor the left side of the n into two factors。
and set each factor equal to zero.3.ns of XXX life problems.4.Vieta's formulas: let x1 and x2 be the roots of the nax^2+bx+c=0.then we have b=-a(x1+x2) and c=a(x1x2).Chapter 3: XXX1.n of a figure: XXX it around a fixed point by a XXX.Properties: the distance from each point of the figure to the center of n remains the same;the angle een the line segment connecting each point and the center of n is equal to the angle of n;the original figure and the XXX.2.XXX to a point if the figure coincides with itself after a180-degree XXX point.A figure is XXX its image under a 180-degree n around apoint is identical to the original figure.3.Coordinates of points XXX to the origin.Chapter 4: Circle1.ns of circle。
transistor n 晶体管diode n 二极管semiconductor n 半导体resistor n 电阻器capacitor n 电容器alternating adj 交互的amplifier n 扩音器,放大器integrated circuit 集成电路linear time invariant systems 线性时不变系统voltage n 电压,伏特数tolerance n 公差;宽容;容忍condenser n 电容器;冷凝器dielectric n 绝缘体;电解质electromagnetic adj 电磁的adj 非传导性的deflection n偏斜;偏转;偏差linear device 线性器件the insulation resistance 绝缘电阻anode n 阳极,正极cathode n 阴极breakdown n 故障;崩溃terminal n 终点站;终端,接线端emitter n 发射器collect v 收集,集聚,集中insulator n 绝缘体,绝热器oscilloscope n 示波镜;示波器gain n 增益,放大倍数forward biased 正向偏置reverse biased 反向偏置P-N junction PN结MOS(metal-oxide semiconductor)金属氧化物半导体enhancement and exhausted 增强型和耗尽型integrated circuits 集成电路analog n 模拟digital adj 数字的,数位的horizontal adj, 水平的,地平线的vertical adj 垂直的,顶点的amplitude n 振幅,广阔,丰富attenuation n衰减;变薄;稀薄化multimeter n 万用表frequency n 频率,周率the cathode-ray tube 阴极射线管dual-trace oscilloscope 双踪示波器signal generating device 信号发生器peak-to-peak output voltage 输出电压峰峰值sine wave 正弦波triangle wave 三角波square wave 方波amplifier 放大器,扩音器oscillator n 振荡器feedback n 反馈,回应phase n 相,阶段,状态filter n 滤波器,过滤器rectifier n整流器;纠正者band-stop filter 带阻滤波器band-pass filter 带通滤波器decimal adj 十进制的,小数的hexadecimal adj/n十六进制的binary adj 二进制的;二元的octal adj 八进制的domain n 域;领域code n代码,密码,编码v编码the Fourier transform 傅里叶变换Fast Fourier Transform 快速傅里叶变换microcontroller n 微处理器;微控制器assembly language instrucions n 汇编语言指令chip n 芯片,碎片modular adj 模块化的;模数的sensor n 传感器plug vt堵,塞,插上n塞子,插头,插销coaxial adj 同轴的,共轴的fiber n 光纤relay contact 继电接触器single instruction programmer 单指令编程器dedicated manufactures programming unit 专供制造厂用的编程单元beam n (光线的)束,柱,梁polarize v(使)偏振,(使)极化Cathode Ray Tube(CRT)阴极射线管neuron n神经元;神经细胞fuzzy adj 模糊的Artificial Intelligence Shell 人工智能外壳程序Expert Systems 专家系统Artificial Intelligence 人工智能Perceptive Systems 感知系统neural network 神经网络fuzzy logic 模糊逻辑intelligent agent 智能代理electromagnetic adj 电磁的coaxial adj 同轴的,共轴的microwave n 微波charge v充电,使充电insulator n 绝缘体,绝缘物nonconductive adj非导体的,绝缘的antenna n天线;触角modeling n建模,造型simulation n 仿真;模拟prototype n 原型array n 排队,编队vector n 向量,矢量wavelet n 微波,小浪sine 正弦cosine 余弦inverse adj倒转的,反转的n反面;相反v倒转high-performance 高精确性,高性能two-dimensional 二维的;缺乏深度的three-dimensional 三维的;立体的;真实的object-oriented programming面向对象的程序设计spectral adj 光谱的attenuation n衰减;变薄;稀释distortion n 失真,扭曲,变形wavelength n 波长refractive adj 折射的ATM 异步传输模式Asynchronous TransferModeADSL非对称用户数字线Asymmetric digitalsubscriber lineVDSL甚高速数字用户线very high data ratedigital subscriber lineHDSL高速数据用户线high rate digitalsubscriber lineFDMA频分多址(Frequency Division MultipleAccess)TDMA时分多址(Time Division Multiple Access)CDMA同步码分多址方式(Code Division MultipleAccess)WCDMA宽带码分多址移动通信系统(WidebandCode Division Multiple Access)TD-SCDMA(Time Division Synchronous CodeDivision Multiple Access)时分同步码分多址SDLC(synchronous data link control)同步数据链路控制HDLC(high-level data link control)高级数据链路控制IP/TCP(internet protocol /transfer ControlProtocol)网络传输控制协议ITU (International Telecommunication Union)国际电信联盟ISO国际标准化组织(InternationalStandardization Organization);OSI开放式系统互联参考模型(Open SystemInterconnect)GSM全球移动通信系统(Global System forMobile Communications)GPRS通用分组无线业务(General Packet RadioService)FDD(frequency division duplex)频分双工TDD(time division duplex)时分双工VPI虚路径标识符(Virtual Path Identifier);ISDN(Integrated Services Digital Network)综合业务数字网IDN综合数字网(integrated digital network)HDTV (high definition television)高清晰度电视DCT(Discrete Cosine Transform)离散余弦变换VCI(virtual circuit address)虚通路标识MAN城域网Metropolitan area networksLAN局域网local area networkWAN广域网wide area network同步时分复用STDM Synchronous Time DivisionMultiplexing统计时分复用STDM Statistical Time DivisionMultiplexing单工传输simplex transmission半双工传输half-duplex transmission全双工传输full-duplex transmission交换矩阵Switching Matrix电路交换circuit switching分组交换packet switching报文交换message switching奇偶校验parity checking循环冗余校验CRC Cyclic Redundancy Check虚过滤Virtual filter数字滤波digital filtering伪随机比特Quasi Random Bit带宽分配Bandwidth allocation信源information source信宿destination数字化digitalize数字传输技术Digital transmission technology灰度图像Grey scale images灰度级Grey scale level幅度谱Magnitude spectrum相位谱Phase spectrum频谱frequency spectrum智能设备Smart Device软切换Soft handover硬切换Hard Handover相干检测Coherent detection边缘检测Edge detection冲突检测collision detection业务集合service integration业务分离/综合service separation/ integration网络集合network integration环形网Ring networks令牌环网Token Ring network网络终端Network Terminal用户终端user terminal用户电路line circuit电路利用率channel utilization(通道利用率)相关性coherence相干解调coherent demodulation数字图像压缩digital image compression图像编码image encoding有损/无损压缩lossy/lossless compression解压decompression呼叫控制Call Control误差控制error control存储程序控制stored program control存储转发方式store-and-forward manner语音\视频传输voice\video transmission视频点播video-on-demand(VOD)会议电视Video Conference有线电视cable television量化quantization吞吐量throughput话务量traffic多径分集Multipath diversity多媒体通信MDM Multimedia Communication多址干扰Multiple Access Interference人机交互man machine interface交互式会话Conversational interaction路由算法Routing Algorithm目标识别Object recognition话音变换Voice transform中继线trunk line传输时延transmission delay远程监控remote monitoring光链路optical link拓扑结构Topology均方根root mean squarewhatsoever=whatever 0switchboard (电话)交换台bipolar (电子)双极的premise (复)房屋,前提cursor (计算机尺的)游标,指导的elapse (时间)经过,消失vaporize (使)蒸发subsystem (系统的)分部,子系统,辅助系统metallic (像)金属的,含金属的,(声音)刺耳的dispatch (迅速)派遣,急件consensus (意见)一致,同意deadline (最后)期限,截止时间tomographic X线体层摄像的alas 唉,哎呀cluster 把…集成一束,一组,一簇,一串,一群encyclopedia 百科全书millionfold 百万倍的semiconductor 半导体radius 半径范围,半径,径向射线half-duplex transmission 半双工传输accompaniment 伴随物,附属物reservation 保留,预定quotation 报价单,行情报告,引语memorandum 备忘录redundancy 备用be viewed as 被看作…be regards as 被认为是as such 本身;照此;以这种资格textual 本文的,正文的verge 边界variation 变化,变量conversion 变化,转化identity 标识;标志criterion 标准,准则in parallel on 并联到,合并到juxtapose 并置,并列dialing pulse 拨号脉冲wave-guide 波导wavelength division multiplexed 波分复用baud rate 波特率playback 播放(录音带,唱片)no greater than 不大于update 不断改进,使…适合新的要求,更新asymmetric 不对称的irrespective 不考虑的,不顾的inevitably 不可避免的inevitable 不可避免的,不可逃避的,必定的segment 部分abrasion 擦伤,磨损deploy 采用,利用,推广应用take the form of 采用…的形式parameter 参数,参量layer 层dope 掺杂FET(field effect transistors) 场效应管audio recording 唱片ultra-high-frequency(UHF) 超高频in excess of 超过in excess of 超过hypertext 超文本ingredient 成分,因素ingredient 成分,组成部分,要素metropolitan-area network(WAN) 城域网metropolitan area network(WAN) 城域网,城市网络congestion 充满,拥挤,阻塞collision 冲突extractive 抽出;释放出extract 抽取,取出,分离lease 出租,租约,租界期限,租界物pass on 传递,切换transmission 传输facsimile 传真innovative=innovatory 创新的,富有革新精神的track 磁道impetus 促进,激励cluster 簇stored-program control(SPC) 存储程序控制a large number of 大量的peal 大声响,发出supersede 代替supplant 代替,取代out-of-band signaling 带外信号simplex transmission 单工传输monochromatic 单色的,单色光的,黑白的ballistic 弹道的,射击的,冲击的conductor 导体hierarchy 等级制度,层次infrastructure 底层结构,基础结构geographic 地理的,地区的geographically 地理上GIS(ground instrumentation system) 地面测量系统ground station 地面站earth orbit 地球轨道extraterrestrial 地球外的,地球大气圈外的Land-sat 地球资源卫星rug 地毯,毯子ignite 点火,点燃,使兴奋electromagnetic 电磁的inductive 电感arc 电弧telephony 电话(学),通话dielectric 电介质,绝缘材料;电解质的,绝缘的capacitor 电容telecommunication 电信,无线电通讯scenario 电影剧本,方案modem pool 调制解调器(存储)池superimposing 叠加,重叠pin 钉住,扣住,抓住customize 定做,定制monolithic 独立的,完全统一的aluminize 镀铝strategic 对全局有重要意义的,战略的substantial 多的,大的,实际上的multi-path fading 多径衰落multi-path 多路,多途径;多路的,多途径的multi-access 多路存取,多路进入multiplex 多路复用multiplex 多路复用的degradation 恶化,降级dioxide 二氧化碳LED(light-emitting-diode) 发光二极管evolution 发展,展开,渐进feedback 反馈,回授dimension 范围,方向,维,元scenario 方案scenario 方案,电影剧本amplifer 放大器noninvasive 非侵略的,非侵害的tariff 费率,关税率;对…征税distributed functional plane(DFP) 分布功能平面DQDB(distributed queue dual bus) 分布式队列双总线hierarchy 分层,层次partition 分成segmentation 分割interface 分界面,接口asunder 分开地,分离地detached 分离的,分开的,孤立的dispense 分配allocate 分配,配给;配给物centigrade 分为百度的,百分度的,摄氏温度的fractal 分形molecule 分子,微小,些微cellular 蜂窝状的cellular 蜂窝状的,格形的,多孔的auxiliary storage(also called secondary storage)辅助存储器decay 腐烂,衰减,衰退negative 负电vicinity 附近,邻近vicinity 附近地区,近处sophisticated 复杂的,高级的,现代化的high-frequency(HF) 高频high definition television 高清晰度电视chromium 铬annotate 给…作注解in terms of 根据,按照disclosure 公布,企业决算公开public network 公用网functionality 功能,功能度mercury 汞resonator 共鸣器resonance 共振whimsical 古怪的,反复无常的administration 管理,经营cursor 光标(显示器),游标,指针optical computer 光计算机photoconductor 光敏电阻optical disks 光盘optically 光学地,光地wide-area networks 广域网specification 规范,说明书silicon 硅the international telecommunication union(ITU)国际电信联盟excess 过剩obsolete 过时的,废弃的maritime 海事的synthetic 合成的,人造的,综合的synthetic 合成的,综合性的rational 合乎理性的rationalization 合理化streamline 合理化,理顺infrared 红外线的,红外线skepticism 怀疑论ring network 环形网hybrid 混合物counterpart 伙伴,副本,对应物electromechanical 机电的,电动机械的Robot 机器人Robotics 机器人技术,机器人学accumulation 积累infrastructure 基础,基础结构substrate 基质,底质upheaval 激变,剧变compact disc 激光磁盘(CD)concentrator 集中器,集线器centrex system 集中式用户交换功能系统converge on 集中于,聚集在…上lumped element 集总元件CAI(computer-aided instruction) 计算机辅助教学computer-integrated manufacturing(CIM) 计算机集成制造computer mediated communication(CMC) 计算机中介通信record 记录register 记录器,寄存器expedite 加快,促进weight 加权accelerate 加速,加快,促进categorize 加以类别,分类in addition 加之,又,另外hypothetical 假设的rigidly 坚硬的,僵硬的compatibility 兼容性,相容性surveillance 监视surveillance 监视retrieval 检索,(可)补救verification 检验simplicity 简单,简明film 胶片,薄膜take over 接管,接任ruggedness 结实threshold 界限,临界值with the aid of 借助于,用,通过wire line 金属线路,有线线路coherent 紧凑的,表达清楚的,粘附的,相干的compact 紧密的approximation 近似undertake 进行,从事transistor 晶体管elaborate 精心制作的,细心完成的,周密安排的vigilant 警戒的,警惕的alcohol 酒精,酒local area networks(LANs) 局域网local-area networks(LANs) 局域网drama 剧本,戏剧,戏剧的演出focus on 聚集在,集中于,注视insulator 绝缘root mean square 均方根uniform 均匀的open-system-interconnection(OSI) 开放系统互连expire 开始无效,满期,终止immunity 抗扰,免除,免疫性take…into account 考虑,重视…programmable industrial automation 可编程工业自动化demountable 可拆卸的tunable 可调的reliable 可靠be likely to 可能,大约,像要videotex video 可视图文电视negligible 可以忽略的aerial 空气的,空中的,无形的,虚幻的;天线broadband 宽(频)带pervasive 扩大的,渗透的tensile 拉力的,张力的romanticism 浪漫精神,浪漫主义discrete 离散,不连续ion 离子force 力量;力stereophonic 立体声的continuum 连续统一体,连续统,闭联集smart 灵巧的;精明的;洒脱的token 令牌on the other hand 另一方面hexagonal 六边形的,六角形的hexagon 六角形,六边形monopoly 垄断,专利video-clip 录像剪辑aluminum 铝pebble 卵石,水晶透镜forum 论坛,讨论会logical relationships 逻辑关系code book 码本pulse code modulation(PCM) 脉冲编码调制roam 漫步,漫游bps(bits per second) 每秒钟传输的比特ZIP codes 美国邮区划分的五位编码susceptible(to) 敏感的,易受…的analog 模拟,模拟量pattern recognition模式识别bibliographic 目录的,文献的neodymium 钕the european telecommunicationstandardization institute(ETSI) 欧洲电信标准局coordinate 配合的,协调的;使配合,调整ratify 批准,认可bias 偏差;偏置deviate 偏离,与…不同spectrum 频谱come into play 其作用entrepreneurial 企业的heuristic methods 启发式方法play a …role(part) 起…作用stem from 起源于;由…发生organic 器官的,有机的,组织的hypothesis 前提front-end 前置,前级potential 潜势的,潜力的intensity 强度coincidence 巧合,吻合,一致scalpel 轻便小刀,解剖刀inventory 清单,报表spherical 球的,球形的distinguish 区别,辨别succumb 屈服,屈从,死global functional plane(GFP) 全局功能平面full-duplex transmission 全双工传输hologram 全息照相,全息图deficiency 缺乏thermonuclear 热核的artifact 人工制品AI(artificial intelligence) 人工智能fusion 熔解,熔化diskettes(also called floppy disk) 软盘sector 扇区entropy 熵uplink 上行链路arsenic 砷neural network 神经网络very-high-frequency(VHF) 甚高频upgrade 升级distortion 失真,畸变identification 识别,鉴定,验明pragmatic 实际的implementation 实施,实现,执行,敷设entity 实体,存在vector quantification 矢量量化mislead 使…误解,给…错误印象,引错vex 使烦恼,使恼火defy 使落空facilitate 使容易,促进retina 视网膜compatible 适合的,兼容的transceiver 收发两用机authorize 授权,委托,允许data security 数据安全性data independence 数据独立data management 数据管理database 数据库database management system(DBMS) 数据库管理信息系统database transaction 数据库事务data integrity 数据完整性,数据一致性attenuation 衰减fading 衰落,衰减,消失dual 双的,二重的transient 瞬时的deterministic 宿命的,确定的algorithm 算法dissipation 损耗carbon 碳diabetes 糖尿病cumbersome 讨厌的,麻烦的,笨重的razor 剃刀,剃go by the name of 通称,普通叫做commucation session 通信会话traffic 通信业务(量)synchronous transmission 同步传输concurrent 同时发生的,共存的simultaneous 同时发生的,同时做的simultaneous 同时发生的,一齐的coaxial 同轴的copper 铜statistical 统计的,统计学的dominate 统治,支配invest in 投资perspective 透视,角度,远景graphics 图示,图解pictorial 图像的coating 涂层,层deduce 推理reasoning strategies 推理策略inference engine 推理机topology 拓扑结构heterodyne 外差法的peripheral 外界的,外部的,周围的gateway 网关hazardous 危险的microwave 微波(的)microprocessor 微处理机,微处理器microelectronic 微电子nuance 微小的差别(色彩等)encompass 围绕,包围,造成,设法做到maintenance 维护;保持;维修satellite communication 卫星通信satellite network 卫星网络transceiver 无线电收发信机radio-relay transmission 无线电中继传输without any doubt 无疑passive satellite 无源卫星sparse 稀少的,稀疏的downlink 下行链路precursor 先驱,前任visualization 显像feasibility 现实性,可行性linearity 线性度constrain 限制,约束,制约considerable 相当的,重要的geo-stationary 相对地面静止by contrast 相反,而,对比起来coorelation 相关性mutual 相互的mutually 相互的,共同的interconnect 相互连接,互连one after the other 相继,依次minicomputer 小型计算机protocol 协议,草案protocol 协议,规约,规程psycho-acoustic 心理(精神)听觉的;传音的channelization 信道化,通信信道选择run length encoding 行程编码groom 修饰,准备virtual ISDN 虚拟ISDNmultitude 许多,大批,大量whirl 旋转preference 选择,喜欢avalanche 雪崩pursue 寻求,从事interrogation 询问dumb 哑的,不说话的,无声的subcategory 亚类,子种类,子范畴orbital 眼眶;轨道oxygen 氧气,氧元素service switching and control points(SSCPs) 业务交换控制点service control points(SCPs) 业务控制点service control function(SCF) 业务控制功能in concert 一致,一齐handover 移交,越区切换at a rate of 以……的速率in the form of 以…的形式base on…以…为基础yttrium 钇(稀有金属,符号Y)asynchronous transmission 异步传输asynchronous 异步的exceptional 异常的,特殊的voice-grade 音频级indium 铟give rise to 引起,使产生cryptic 隐义的,秘密的hard disk 硬盘hard automation 硬自动化by means of 用,依靠equip with 用…装备subscriber 用户telex 用户电报PBX(private branch exchange) 用户小交换机或专用交换机be called upon to 用来…,(被)要求…superiority 优势predominance 优势,显著active satellite 有源卫星in comparison with 与…比较comparable to 与…可比preliminary 预备的,初步的premonition 预感,预兆nucleus 原子核valence 原子价circumference 圆周,周围teleprocessing 远程信息处理,遥控处理perspective 远景,前途constrain 约束,强迫mobile 运动的,流动的,机动的,装在车上的convey 运输,传递,转换impurity 杂质impurity 杂质,混杂物,不洁,不纯regenerative 再生的improve over 在……基础上改善play important role in 在…中起重要作用in close proximity 在附近,在很近underlying 在下的,基础的in this respect 在这方面entail 遭遇,导致presentation 赠与,图像,呈现,演示narrowband 窄(频)带deploy 展开,使用,推广应用megabit 兆比特germanium 锗positive 正电quadrature 正交orthogonal 正交的quadrature amplitude modulation(QAM) 正交幅度调制on the right track 正在轨道上sustain 支撑,撑住,维持,持续outgrowh 支派;长出;副产品dominate 支配,统治knowledge representation 知识表示knowledge engineering 知识工程knowledge base 知识库in diameter 直径helicopter 直升飞机acronym 只取首字母的缩写词as long as 只要,如果tutorial 指导教师的,指导的coin 制造(新字符),杜撰fabrication 制造,装配;捏造事实proton 质子intelligence 智能,智力,信息intelligent network 智能网intermediate 中间的nucleus(pl.nuclei) 中心,核心neutrons 中子terminal 终端,终端设备overlay 重叠,覆盖,涂覆highlight 重要的部分,焦点charge 主管,看管;承载dominant 主要的,控制的,最有力的cylinder 柱面expert system 专家系统private network 专用网络transition 转变,转换,跃迁relay 转播relay 转播,中继repeater 转发器,中继器pursue 追赶,追踪,追求,继续desktop publish 桌面出版ultraviolet 紫外线的,紫外的;紫外线辐射field 字段vendor 自动售货机,厂商naturally 自然的;天生具备的synthesize 综合,合成integrate 综合,使完全ISDN(intergrated services digital network) 综合业务数字网as a whole 总体上bus network 总线形网crossbar 纵横,交叉impedance 阻抗initial 最初的,开始的optimum 最佳条件appear as 作为…出现A Analog 模拟A/D Analog to Digital 模-数转换AAC Advanced Audio Coding 高级音频编码ABB Automatic Black Balance 自动黑平衡ABC American Broadcasting Company 美国广播公司Automatic Bass Compensation 自动低音补偿Automatic Brightness Control 自动亮度控制ABL Automatic Black Level 自动黑电平ABLC Automatic Brightness LimiterCircuit 自动亮度限制电路ABU Asian Broadcasting Union 亚洲广播联盟(亚广联ABS American Bureau of Standard 美国标准局AC Access Conditions 接入条件Audio Center 音频中心ACA Adjacent Channel Attenuation 邻频道衰减ACC Automatic Centering Control 自动中心控制Automatic Chroma Control 自动色度(增益ACK Automatic Chroma Killer 自动消色器ACP Additive Colour Process 加色法ACS Access Control System 接入控制系统Advanced Communication Service 高级通信业务Area Communication System 区域通信系统ADC Analog to Digital Converter 模-数转换器Automatic Degaussirng Circuit 自动消磁电路ADL Acoustic Delay Line 声延迟线ADS Audio Distribution System 音频分配系统AE Audio Erasing 音频(声音AEF Automatic Editing Function 自动编辑功能AES Audio Engineering Society 音频工程协会AF Audio Frequency 音频AFA Audio Frequency Amplifier 音频放大器AFC Automatic Frequency Coder 音频编码器Automatic Frequency Control 自动频率控制AFT Automatic Fine Tuning 自动微调Automatic Frequency Track 自动频率跟踪Automatic Frequency Trim 自动额率微调AGC Automatic Gain Control 自动增益控制AI Artificial Intelligence 人工智能ALM Audio-Level Meter 音频电平表AM Amplitude Modulation 调幅AMS Automatic Music Sensor 自动音乐传感装置ANC Automatic Noise Canceller 自动噪声消除器ANT ANTenna 天线AO Analog Output 模拟输出APS Automatic Program Search 自动节目搜索APPS Automatic Program Pause System自动节目暂停系统APSS Automatic Program Search System自动节目搜索系统AR Audio Response 音频响应ARC Automatic Remote Control 自动遥控ASCII American Standard Code forInformation Interchange 美国信息交换标准AST Automatic Scanning Tracking 自动扫描跟踪ATC Automatic Timing Control 自动定时控制Automatic Tone Correction 自动音频校正ATM Asynchronous Transfer Mode 异步传输模式ATF Automatic Track Finding 自动寻迹ATS Automatic Test System 自动测试系统ATSC Advanced Television SystemsCommittee (美国高级电视制式委员会)***C Automatic Volume Control 自动音量控制***R Automatic Voltage Regulator 自动稳压器AWB Automatic White Balance 自动白平衡AZC Automatic Zooming Control 自动变焦控制AZS Automatic Zero Setting 自动调零BA Branch Amplifier 分支放大器Buffer Amplifier 缓冲放大器BAC Binary-Analog Conversion 二进制模拟转换BB Black Burst 黑场信号BBC British Broadcasting Corporation 英国广播公司BBI Beijing Broadcasting Institute 北京广播学院BC Binary Code 二进制码Balanced Current 平衡电流Broadcast Control 广播控制BCT Bandwidth Compression Technique 带宽压缩技术BDB Bi-directional Data Bus 双向数据总线BER Basic Encoding Rules 基本编码规则Bit Error Rate 比特误码率BF Burst Flag 色同步旗脉冲BFA Bare Fiber Adapter 裸光纤适配器Brillouin Fiber Amplifier 布里渊光纤放大器BGM Background Music 背景音乐BIOS Basic Input/Output System 基本输入输出系统B-ISDN Broadband-ISDN 宽带综合业务数据网BIU Basic Information Unit 基本信息单元Bus Interface Unit 总线接口单元BM Bi-phase Modulation 双相调制BML Business Management Layer 商务管理层BN Backbone Network 主干网BNT Broadband Network Termination 宽带网络终端设备BO Bus Out 总线输出BPG Basic Pulse Generator 基准脉冲发生器BPS Band Pitch Shift 分频段变调节器BSI British Standard Institute 英国标准学会BSS Broadcast Satellite Service 广播卫星业务BT Block Terminal 分线盒、分组终端British Telecom 英国电信BTA Broadband Terminal Adapter 宽带终端适配器Broadcasting Technology Association (日本BTL Balanced Transformer-Less 桥式推挽放大电路BTS Broadcast Technical Standard 广播技术标准BTU Basic Transmission Unit 基本传输单元BVU Broadcasting Video Unit 广播视频型(一种3/4英寸带录像机记录格式BW BandWidth 带宽BWTV Black and White Television 黑白电视CA Conditional Access 条件接收CAC Conditional Access Control 条件接收控制CAL Continuity Accept Limit 连续性接受极限CAS Conditional Access System 条件接收系统Conditional Access Sub-system 条件接收子系统CATV Cable Television 有线电视,电缆电视Community Antenna Television 共用天线电视C*** Constant Angular Velocity 恒角速度CBC Canadian Broadcasting Corporation 加拿大广播公司CBS Columbia Broadcasting System (美国哥伦比亚广播公司CC Concentric Cable 同轴电缆CCG Chinese Character Generator 中文字幕发生器CCIR International Radio Consultative Committee 国际无线电咨询委员会CCITT International Telegraph andTelephone ConsultativeCommittee 国际电话电报咨询委员会CCR Central Control Room 中心控制室CCTV China Central Television 中国中央电视台Close-Circuit Television 闭路电视CCS Center Central System 中心控制系统CCU Camera Control Unit 摄像机控制器CCW Counter Clock-Wise 反时针方向CD Compact Disc 激光唱片CDA Current Dumping Amplifier 电流放大器CD-E Compact Disc Erasable 可抹式激光唱片CDFM Compact Disc 光盘文件管理(程序CDPG Compact-Disc Plus Graphic 带有静止图像的CD唱盘CD-ROM Compact Disc-Read OnlyMemory 只读式紧凑光盘CETV China Educational Television 中国教育电视台CF Color Framing 彩色成帧CGA Color Graphics Adapter 彩色图形(显示卡CI Common Interface 通用接口CGA Color Graphics Adapter 彩色图形(显示卡CI Common Interface 通用接口CIE Chinese Institute of Electronics 中国电子学会CII China Information Infrastructure 中国信息基础设施CIF Common Intermediate Format 通用中间格式CIS Chinese Industrial Standard 中国工业标准CLV Constant Linear Velocity 恒定线速度CM Colour Monitor 彩色监视器CMTS Cable Modem Termination System线缆调制解调器终端系统CNR Carrier-to-Noise Ratio 载噪比CON Console 操纵台Controller 控制器CPB Corporation of Public Broadcasting(美国公共广播公司CPU Central Processing Unit 中央处理单元CRC Cyclic Redundancy Check 循环冗余校验CRCC CRI Cyclic Redundancy Check Code循环冗余校验码CROM China Radio International 中国国际广播电台CRT Control Read Only Memory 控制只读存储器CS Cathode-Ray Tube 阴极射线管CSC Communication Satellite 通信卫星CSS Color Sub-carrier 彩色副载波Center Storage Server 中央存储服务器Content Scrambling System 内容加扰系统CSU Channel Service Unit 信道业务单元CT Color Temperature 色温CTC Cassette Tape Controller 盒式磁带控制器Channel Traffic Control 通道通信量控制Counter Timer Circuit 计数器定时器电路Counter Timer Control 计数器定时器控制CTE Cable Termination Equipment 线缆终端设备Customer Terminal Equipment 用户终端设备CTV Color Television 彩色电视CVD China Video Disc 中国数字视盘CW Carrie Wave 载波DAB Digital Audio Broadcasting 数字音频广播DASH Digital Audio Stationary Head 数字音频静止磁头DAT Digital Audio Tape 数字音频磁带DBMS Data Base Management System 数据库管理系统DBS Direct Broadcast Satellite 直播卫星DCC Digital Compact Cassette 数字小型盒带Dynamic Contrast Control 动态对比度控制DCT Digital Component Technology 数字分量技术Discrete Cosine Transform 离散余弦变换DCTV Digital Color Television 数字彩色电视DD Direct Drive 直接驱动DDC Direct Digital Control 直接数字控制DDE Dynamic Data Exchange 动态数据交换DDM Data Display Monitor 数据显示监视器DES Data Elementary Stream 数据基本码流Data Encryption Standard 美国数据加密标准DF Dispersion Flattened 色散平坦光纤DG Differential Gain 微分增益DI Digital Interface 数字接口DITEC Digital Television Camera 数字电视摄像机DL Delay Line 延时线DLD Dynamic Linear Drive 动态线性驱动DM Delta Modulation 增量调制Digital Modulation 数字调制DMB Digital Multimedia Broadcasting 数字多媒体广播DMC Dynamic Motion Control 动态控制DME Digital Multiple Effect 数字多功能特技DMS Digital Mastering System 数字主系统DN Data Network 数据网络DNG Digital News Gathering 数字新闻采集DNR Digital Noise Reducer 数字式降噪器DOB Data Output Bus 数据输出总线DOCSIS Data Over Cable ServiceInterface Specifications 有线数据传输业务接口规范DOC Drop Out Compensation 失落补偿DOS Disc Operating System 磁盘操作系统DP Differential Phase 微分相位Data Pulse 数据脉冲DPCM Differential Pulse Code Modulation差值脉冲编码调制DPL Dolby Pro Logic 杜比定向逻辑DSB Digital Satellite Broadcasting 数字卫星广播DSC Digital Studio Control 数字演播室控制DSD Dolby Surround Digital 杜比数字环绕声DSE Digital Special Effect 数字特技DSK Down-Stream Key 下游键DSP Digital Signal Processing 数字信号处理Digital Sound Processor 数字声音处理器DSS Digital Satellite System 数字卫星系统DT Digital Technique 数字技术Digital Television 数字电视Data Terminal 数据终端Data Transmission 数据传输DTB Digital Terrestrial Broadcasting 数字地面广播DTBC Digital Time-Base Corrector 数字时基校正器DTC Digital Television Camera 数字电视摄像机DTS Digital Theater System 数字影院系统Digital Tuning System 数字调谐系统Digital Television Standard 数字电视标准DVB Digital Video Broadcasting 数字视频广播DVC Digital Video Compression 数字视频压缩DVE Digital Video Effect 数字视频特技DVS Desktop Video Studio 桌上视频演播DVTR Digital Video Tape Recorder 数字磁带录像机EA Extension Amplifier 延长放大器EB Electron Beam 电子束EBS Emergency Broadcasting System 紧急广播系统EBU European Broadcasting Union 欧洲广播联盟EC Error Correction 误差校正ECN Emergency Communications Network 应急通信网络ECS European Communication Satellite 欧洲通信卫星EDC Error Detection Code 错误检测码EDE Electronic Data Exchange 电子数据交换EDF Erbium-Doped Fiber 掺饵光纤EDFA Erbium-Doped Fiber Amplifier 掺饵光纤放大器EDL Edit Decision List 编辑点清单EDTV Extended Definition Television 扩展清晰度电视EE Error Excepted 允许误差EFM Eight to Fourteen Modulation 8-14调制EFP Electronic Field Production 电子现场节目制作EH Ethernet Hosts 以太网主机EIN Equivalent Input Noise 等效输入噪声EIS Electronic Information System 电子信息系统EISA Extended Industrial Standard Architecture 扩展工业标准总线EL Electro-Luminescent 场致发光EM Error Monitoring 误码监测EN End Node 末端节点ENG Electronic News Gathering 电子新闻采集EOT End of Tape 带尾EP Edit Point 编辑点Error Protocol 错误协议EPG Electronic Program Guides 电子节目指南EPS Emergency Power Supply 应急电源ERP Effective Radiated Power 有效辐射功率ES Elementary Stream 基本码流End System 终端系统ESA European Space Agency 欧洲空间局ETV Education Television 教育电视FA Enhanced Television 增强电视FABM FAS Facial Animation 面部动画FC Fiber Amplifier Booster Module 光纤放大器增强模块Fiber Access System 光纤接入系统Frequency Changer 变频器FCC Fiber Channel 光纤通道FD Film Composer 电影编辑系统Federal Communications Commission 美国联邦通信委员会FDCT Frequency Divider 分频器FDDI FDM Fiber Duct 光纤管道FDP Forward Discrete Cosine Transform 离散余弦正变换FE Fiber Distributed Data Interface 分布式光纤数据接口Frequency-Division Multiplexing 频分复用FF Fiber Distribution Point 光纤分配点FG Front End 前端FH Framing Error 成帧误差FIT Fast Forward 快进FN Frequency Generator 频率发生器FOA Frequency Hopping 跳频FOC Frame-Interline Transfer 帧一行间转移Fiber Node 光纤节点Fiber Optic Amplifier 光纤放大器FOM Fiber Optic Cable 光缆FON Fiber Optic Communications 光纤通信FOS Fiber Optic Coupler 光纤耦合器FOTC Fiber Optic Modem 光纤调制解调器FS Fiber Optic Net 光纤网Factor of Safety 安全系数Fiber Optic Trunk Cable 光缆干线FT Frame Scan 帧扫描Store 帧存储器FTTB Frame Synchro 帧同步机FTTC France Telecom 法国电信Absorber Circuit 吸收电路AC/AC Frequency Converter 交交变频电路AC power control交流电力控制AC Power Controller交流调功电路AC Power Electronic Switch交流电力电子开关Ac Voltage Controller交流调压电路Asynchronous Modulation异步调制Baker Clamping Circuit贝克箝位电路Bi-directional Triode Thyristor双向晶闸管Bipolar Junction Transistor-- BJT双极结型晶体管Boost-Buck Chopper升降压斩波电路Boost Chopper升压斩波电路Boost Converter升压变换器Bridge Reversible Chopper桥式可逆斩波电路Buck Chopper降压斩波电路Buck Converter降压变换器Commutation换流Conduction Angle导通角Constant Voltage Constant Frequency --CVCF恒压恒频Continuous Conduction--CCM(电流)连续模式Control Circuit 控制电路Cuk Circuit CUK 斩波电路Current Reversible Chopper电流可逆斩波电路Current Source Type Inverter--CSTI 电流(源)型逆变电路Cyclo convertor周波变流器DC-AC-DC Converter直交直电路DC Chopping直流斩波DC Chopping Circuit直流斩波电路DC-DC Converter直流-直流变换器Device Commutation器件换流Direct Current Control直接电流控制Discontinuous Conduction mode (电流)断续模式displacement factor 位移因数distortion power 畸变功率double end converter 双端电路driving circuit 驱动电路electrical isolation 电气隔离fast acting fuse 快速熔断器fast recovery diode快恢复二极管fast revcovery epitaxial diodes 快恢复外延二极管fast switching thyristor快速晶闸管field controlled thyristor场控晶闸管flyback converter 反激电流forced commutation 强迫换流forward converter 正激电路frequency converter 变频器full bridge converter全桥电路full bridge rectifier 全桥整流电路full wave rectifier 全波整流电路fundamental factor基波因数gate turn-off thyristor——GTO 可关断晶闸管general purpose diode 普通二极管giant transistor——GTR 电力晶体管half bridge converter 半桥电路hard switching 硬开关high voltage IC 高压集成电路hysteresis comparison 带环比较方式indirect current control间接电流控制indirect DC-DC converter直接电流变换电路insulated-gate bipolar transistor---IGBT绝缘栅双极晶体管intelligent power module---IPM智能功率模块integrated gate-commutated thyristor---IGCT集成门极换流晶闸管inversion 逆变latching effect 擎住效应leakage inductance 漏感light triggered thyristor---LTT光控晶闸管line commutation 电网换流load commutation 负载换流loop current 环流1 backplane 背板2 Band gap voltage reference 带隙电压参考3 bench top supply 工作台电源4 Block Diagram 方块图5 Bode Plot 波特图6 Bootstrap 自举7 Bottom FET Bottom FET8 bucket capacitor 桶形电容9 chassis 机架11 constant current source 恒流源12 Core Saturation 铁芯饱和13 crossover frequency 交叉频率14 current ripple 纹波电流15 Cycle by Cycle 逐周期16 cycle skipping 周期跳步17 Dead Time 死区时间18 DIE Temperature 核心温度19 Disable 非使能,无效,禁用,关断20 dominant pole 主极点21 Enable 使能,有效,启用22 ESD Rating ESD额定值23 Evaluation Board 评估板24 Exceeding the specifications below mayresult in permanent damage to the device, ordevice malfunction. Operation outside of theparameters specified in the ElectricalCharacteristics section is not implied. 超过下面的规格使用可能引起永久的设备损害或设备故障。
必修二U4 Stage and Screen单元要点Ⅰ.核心单词1.He was crossing the street when a man was driving fast towards him and he narrowly ________ (逃脱) being knocked down.2.In the early days, Peking ________ (歌剧) was performed on open-air or in teahouses.3.American English differs from British English in many ________ (方面).4.This dictionary is available in electronic ________ (版本).5.A high percentage of the ________ (女性的) staff in the company are part-time workers.6.At the same time, he attempted to invent a new ________ (技术) to reduce the cost.7.We are not sure when the ________ (宇宙) came into being.8.Have you ever dreamed of being in front of thousands of people at a concert, with everyone ________ (鼓掌) while you are singing?9.The ________ (纪录片) gives a fascinating account of life onstage and backstage.10.You should ________ (鼓掌) warmly while the performers bow on the stage.11.The book is well organised in terms of ________ (情节).12.We can ________ (克服) any difficulty, however great it is.13.They enjoyed a ________ (浪漫的) dinner for two at one of their favourite restaurants.14.Make sure that the baby is not sleeping in a(n) ________( 不舒适的) position.15.It's ________ (正常的) to feel tired after such a long trip.16.We stopped by Mary's house for a ________ (短暂的) visit.Ⅱ.拓展词汇会书写1. ________ n.运动,动作→move v.移动2.________ v.使改观,使变形,使转化→transformation n.变化,改观,转变3.________ adj.难以置信的→incredibly ad v.难以置信地4.________ adj.精力充沛的,充满活力的→energy n.精力;能源5.________ n.强烈的情感→emotional adj.感情的;情感的6.________ n.愤怒,怒火→angry adj.生气的7.________ v.(使)结合,(使)组合→combination n.组合;结合8.________ n.诗,诗歌→poet n.诗人→poem n.诗,诗歌9.________ adj.爆炸(式)的,爆发的→explode v.(使)爆炸10.________ adj.感谢的,感激的→gratitude n.感激之情;感谢11.________ ad v.极度,极其→extreme adj.极度的12.________ adj.专心致志的→absorb v.吸收;理解;使专注→absorbing adj.十分吸引人的13.________ ad v.完全地,绝对地→absolute adj.绝对的;完全的;确实的14.________ adj.有吸引力的,有趣的→appeal v.呼吁,恳请;对……有吸引力15.________ ad v.确切地,肯定地→definite adj.明确的16.________ adj.粗鲁的,无礼的→rudeness n.粗鲁;无礼17.________ n.交通运输系统,运输方式→transportation n.交通18.________ n.安排,筹划→arrange v.安排;布置19.________ adj.失望的,沮丧的→disappoint v t.使失望→disappointing adj.令人失望的→disappointment n.失望;沮丧;扫兴;使人失望的人(或事物) 20.________ adj.原先的,最初的→origin n.起源21.________ v.表现→behaviour n.行为;举动22.________ n.责任→responsible adj.有责任的;负责的23.________ n.缺乏,没有→absent adj.缺席的;不在的会应用1.During the ________ (transform) of kung fu, it was greatly influenced by Taoism and Zen.2.He was filled with ________ (angry) at the way his mother had been punished.3.If he can combine his ability ________ hard work, he should be very successful.4.I'm so grateful ________ all those volunteers because they helped my terrible day end happily.5.①When we read a novel we become ________ (absorb) in the plot and characters.②The book was so ________ (absorb) that she read on without a break.6.①It creates an atmosphere which visitors find so ________ (appeal).②It's suggested that the government appeal to the citizens ________ (save) water.7.①Never mind.I'll make ________ (arrange) for you to be met at the airport.②I have arranged for my assistant ________ (take) my place to attend the meeting.8.①The teacher is disappointed ________ Tony's attitude towards study.②The fans were disappointed ________ the film star when they learned some negative news about him on the website.③We were greatly disappointed ________ (find) that she was absent.④This was very ________ (disappoint) for me, especially because all the others showed so much improvement.⑤To my ________ (disappoint), his ________ (behave) caused some misunderstanding between us.9.①Parents need to inspire a sense of ________ (responsible) in their children.②No one wants to take responsibility ________ the problem.③It's your responsibility ________ (inform) us of any change.10.①Learning English as a foreign language is very difficult ________ the absence of a native language environment.②My teachers and classmates helped me with the lessons after my long absence ________ school.③He was absent ________ the conference yesterday because of his sudden heart disease.Ⅲ.重点短语会书写1.date__back__to追溯到;始于2.get__across 解释清楚,传达3.transform...into... 把……变成……4.on__the__edge__of__one's__seat 极为激动5.tick__all__the__right__boxes 事情发展如人所愿,一切顺利6.base...on 以……为基础7.all__too__often 通常8.result__in 导致,造成9.put__on 表演(节目)10.live__up__to 符合(标准),不负(盛名)11.to__some__extent 在某种程度上12.in__one's__own__right 凭借自身;靠自己13.turn__to 转向;求助于即时练习1.The famous singer will ________ a performance at the Shanghai Gymnasium next month.2.The classic superheroes like Spiderman or Superman ________ many decades ago.3.John has a unique way to ________ his opinion by using as few words as possible.4.It is true that his father is a world-famous movie star, but Jack becomes famous ________.5.________ these problems affected the development of China's foreign trade.6.The new film will keep you ________.7.The newest thriller ________ the author's fans will be hoping for.8.The car accident ________ the death of two passengers.Ⅳ.重点句型单句语法填空1.________( taste) terrible, the medicine was thrown away by the child.2.(2019·北京卷)Nervously ________ (face) challenges, I know I will whisper to myself the two simple words “Be yourself”.3.________( cover) an area of over 4,000 square kilometers, Qinghai Lake is also the biggest saltwater lake in China.4.________( receive) no reply, he decided to write another letter to the personnel manager about his job application.5.________( hear) the news, she rushed out and disappeared into the distance, ________( leave) the book lying open on the table.。
正交变换法和配方法化二次型标准形-CAL-FENGHAI-(2020YEAR-YICAI)_JINGBIAN正交变换法和配方法化二次型标准形的优劣研究摘要二次型的研究起源于解析几何,在平面解析几何中,通常需要把二次曲线与二次曲面方程化为标准方程.从代数学的观点看,这种变化过程就是通过变量的线性替换化简一个二次多项式,使之只含有各个变量的平方项的过程.这类问题在数学的各个分支及物理、力学和网络计算中都有重要应用.本文在对二次型概念的理解基础上,将二次型化为标准形的方法进行归纳整理,并做进一步的研究与讨论.总结出正交变换法和配方法化二次型标准形的优劣之处.关键词:二次型;标准形;配方法;正交变换法AbstractQuadratic study originated in analytic geometry. In graphic analytic geometry, usually need to second curve and surface equation into standard equation. From the point of view of algebra, the change process of replacement is through simplifying linear variable, a quadratic multinomial only contains the square of variables. This kind of question in each branch of mathematics, physics,mechanics and network computing have important applications.Based on the understanding of quadratic basis, induce the method of transform quadratic form into standard form, and further generalization of the research and discussion. Summarize the advantage and disadvantage of orthogonal transformation method and the method of completing square.Keywords: Quadratic form; Standard form; Method of completing square; Method of orthogonal transformation目录摘要 (Ⅰ)Abstract (Ⅱ)目录 (Ⅲ)1.引言 (1)2.定义 (1)3.定理及其证明 (2)4.方法步骤及例题 (5)配方法化二次型标准形 (5)正交变换法化二次型标准形 (7)两种方法的比较研究 (9)5.小结 (10)致谢 (12)参考文献 (13)1. 引言线性代数理论有着悠久的历史和丰富的内容,随着科学技术的发展,特别是电子计算机使用的日益普遍,作为重要的数学工具之一,线性代数的应用已经深入到了自然科学、社会科学、工程技术、经济、管理等各个领域.二次型理论在线性代数中占有举足轻重的地位,从对平方数的注意到对特殊二次型的研究,再到对一般二次型的探索与发展,中间经历了一个漫长曲折的历史过程,而实二次型的标准形与代数数论、数的几何等都有密切的联系,利用二次型可以把任何一个方阵JORDAN标准化,对研究矩阵是非常有用的,因此讨论化二次型为标准形的问题就成为教学的一个很重要的内容.文献[1]-[3]具体介绍了二次型的定义以及对二次型的研究情况,提出了化二次型为标准型的重要性.文献[4]-[6]提出了用正交变换法化二次型标准形的步骤及应用.文献[7]-[8]提出了用配方法化二次型标准形的步骤及应用.本文对化二次型为标准形的方法进行了归纳和总结,并做进一步的研究与讨论,这在理论上和应用上都有着十分重要的意义.2. 定 义定义 1:设P 是一数域,一个系数在数域P 中的n x x x ,,,21 的二次齐次多项式()n x x x f ,,,21 =11a 21x +22112x x a +…+2n n x x a 11+2222x a +…2n n x x a 22+…2n nn x a称为数域P 上的一个n 元二次型,简称二次型.定义 2:设n x x ,,1 ;n y y ,,1 是两组文字,系数在数域P 中的一组关系式⎪⎪⎩⎪⎪⎨⎧+++=+++=+++=nnn n n n nn n n y c y c y c x y c y c y c x y c y c y c x22112222211212121111(1)称为由n x x ,,1 到n y y ,,1 的一个线性替换,简称线性替换.如果系数行列式 0≠ij c ,那么,线性替换(1)就称为非退化的.定义 3:在n 维欧式空间中,由n 个向量组成的正交向量组称为正交基,由单位向量组成的正交基称为标准正交基.3. 定理及其证明定理 1:数域P 上任意一个二次型都可以经过非退化线性替换变成平方和2222211n n x d x d x d +++ 的形式.证明:对变量的个数n 作归纳法.对于n=1,二次型就是()21111x a x f =,已经是平方和了,现假定对n-1元的二次型,定理的结论成立.再设()∑∑===ni nj j i ij n x x a x x x f 2221,,, (ji ij a a =)分三种情形来讨论:1)ij a (n i ,,2,1 =)中至少有一个不为零,例如011≠a ,这时()n x x x f ,,,21 =∑∑∑∑====+++ni nj j i ij ni i i nj j j x x a x x a x x a x a 222112112111=∑∑∑===++n i nj j i ij n j j j x x a x x a x a 2221121112= 212111111⎪⎪⎭⎫ ⎝⎛+∑=-j j n j x a a x a -221111⎪⎪⎭⎫ ⎝⎛∑=-n j j j x a a +∑∑==n i n j j i ij x x a 22= 212111111⎪⎪⎭⎫ ⎝⎛+∑=-j j n j x a a x a +∑∑==n i n j j i ij x x b 22这里 ∑∑==ni nj j i ij x x b 22=-221111⎪⎪⎭⎫ ⎝⎛∑=-n j j j x a a +∑∑==n i n j j i ij x x a 22是一个n x x x ,,,32 的二次型. 令 ⎪⎪⎪⎩⎪⎪⎪⎨⎧==+=∑=-n n nj jj x y x y x a a x y 222111111即 ⎪⎪⎪⎩⎪⎪⎪⎨⎧==-=∑=-n n nj jj x y x y x a a y x 222111111 这是一个非退化线性替换,它使()n x x x f ,,,21 =∑∑==+ni nj j i ij y y b y a 222111由归纳法假定,对∑∑==n i nj j i ij y y b 22有非退化线性替换⎪⎪⎩⎪⎪⎨⎧+++=+++=+++=nnn n n n nn n n y c y c y c z y c y c y c z y c y c y c z 33223333232323232222能使它变成平方和2233222n n z d z d z d +++于是非退化线性变换 ⎪⎪⎩⎪⎪⎨⎧++=++==nnn n n nn y c y c z y c y c z y z 222222211就使()n x x x f ,,,21 变成()n x x x f ,,,21 =22222111n n z d z d z a +++ , 即变成平方和了.根据归纳法原理,定理得证.2)所有0=ii a ,但是至少有一01≠j a (j>1),不失普遍性,设012≠a令 ⎪⎪⎪⎩⎪⎪⎪⎨⎧==-=+=nn z x z x z z x z z x 33212211它是非退化线性变换,且使 ()n x x x f ,,,21 = +21122x x a=()() +-+2121122z z z z a= +-2212211222z a z a , 这时上式右端是n z z z ,,,21 的二次型,且21z 的系数不为零,属于第一种情况,定理成立.3)011211====n a a a由于对称性,有013121====n a a a这时()n x x x f ,,,21 =∑∑==ni nj j i ij x x a 22是n-1元二次型,根据归纳法假定,它能用非退化线性替换变成平方和.定理2:对于任一个n 级实对称矩阵A ,都存在正交矩阵Q ,使得AQ Q 1-=AQ Q '=⎪⎪⎪⎪⎪⎭⎫⎝⎛n λλλ21其中n λλλ,,,21 是A 的n 个特征值.定理 3:对于n 维欧式空间中任意一组基n εεε,,,21 ,都可以找到一组标准正交基n ηηη,,,21 ,使L ()i εεε,,,21 =L ()i ηηη,,,21 ,n i ,,2,1 =.证明:设n εεε,,,21 是一组基,我们来逐个地求出向量n ηηη,,,21 . 首先,可取1111εεη=.一般地,假定已经求出m ηηη,,,21 ,它们是单位正交的,具有性质 L ()i εεε,,,21 =L ()i ηηη,,,21 ,m i ,,2,1 =.下一步求1+m η因为L ()m εεε,,,21 =L ()m ηηη,,,21 ,所以1+m ε不能被m ηηη,,,21 线性表出. 作向量()∑=+++-=mi i i m m m 1111,ηηεεξ.显然,01≠+m ξ,且()0,11=+ηξm ,m i ,,2,1 =令 111+++=m m m ξξη ,121,,,,+m m ηηηη 就是一单位正交向量组. 同时 L ()121,,,+m εεε =L ()121,,,+m ηηη 由归纳法原理,定理得证.定理 4:任意一个n 元二次型()n x x x f ,,,21 =AX X '(A 实对称),总可以经过正交变换QY X =(Q 为正交矩阵)化为标准形2222211n n y y y f λλλ+++= ,式中,n λλλ,,,21 是矩阵A =(ij a )的全部特征值,2222211n n y y y f λλλ+++= 称为二次型在正交变换下的标准形.证明:因为矩阵A 是实对称阵,由定理4可知,一定存在正交矩阵Q ,使得 AQ Q 1-=AQ Q '=A =⎪⎪⎪⎪⎪⎭⎫⎝⎛n λλλ21其中n λλλ,,,21 是矩阵A 的全部特征值.作正交变换QY X =,则()n x x x f ,,,21 =AX X '=()Y AQ Q Y ''=AY Y '=2222211n n y y y λλλ+++4. 方法步骤及例题配方法化二次型标准形用配方法化二次型为标准形的关键是消去交叉项,分如下两种情形处理: 情形1: 如果二次型()n x x x f ,,,21 含某文字例如1x 的平方项,而011≠a ,则集中二次型中含1x 的所有交叉项,然后与21x 配方,并作非退化线性替换⎪⎪⎩⎪⎪⎨⎧==+++=nn n n x y x y x c x c x c y 2212121111(P c ij ∈)则()n y y g y d f ,,2211 +=,其中()n y y g ,2是n y y ,,2 的二次型。
折纸兔子英语作文初一Origami RabbitOrigami is the ancient Japanese art of paper folding. It has a long and rich history, dating back to the 6th century when Buddhist monks first introduced paper to Japan. Over the centuries, origami has evolved from a simple pastime to a sophisticated art form, with complex designs and intricate folds. One of the most iconic origami creations is the rabbit.The origami rabbit is a classic and beloved design that has captured the imagination of people around the world. It is a symbol of grace, agility, and good luck, and its simple yet elegant form has made it a favorite among both experienced and novice origami artists.The process of creating an origami rabbit is both challenging and rewarding. It requires a steady hand, a keen eye, and a deep understanding of the principles of paper folding. The basic steps involve starting with a square sheet of paper, making a series of precise folds, and gradually shaping the paper into the distinctiverabbit form.One of the most important aspects of creating an origami rabbit is the choice of paper. The ideal paper should be thin, yet sturdy, with a smooth surface that allows for clean, crisp folds. Many origami enthusiasts prefer to use specialized origami paper, which comes in a variety of colors and patterns. However, any type of thin, high-quality paper can be used, from newspaper to wrapping paper.The first step in creating an origami rabbit is to start with a square sheet of paper. This can be achieved by taking a rectangular sheet of paper and folding it diagonally to create a triangle, then folding the triangle in half to create a square. Once the paper is properly prepared, the folding process can begin.The basic origami rabbit design involves a series of folds that gradually transform the square into the distinct rabbit shape. This includes making a series of diagonal folds to create the rabbit's ears, followed by more intricate folds to shape the body and legs. The final step is to add the finishing touches, such as defining the rabbit's features and adding any additional details.One of the most challenging aspects of creating an origami rabbit is maintaining the integrity of the paper throughout the folding process. Each fold must be precise and clean, and the paper must behandled with care to avoid tearing or creasing. This requires a steady hand and a keen eye for detail, as well as a deep understanding of the underlying principles of origami.Despite the challenges, the process of creating an origami rabbit can be deeply rewarding. The sense of accomplishment that comes from successfully folding a complex design is unparalleled, and the finished product can be a beautiful and unique work of art.In addition to its artistic value, the origami rabbit also has a rich cultural significance. In Japan, the rabbit is a symbol of good luck and prosperity, and the origami rabbit is often given as a gift or used in various cultural celebrations and ceremonies.Beyond its cultural significance, the origami rabbit also has practical applications. It can be used as a decorative element in the home or office, or as a fun and educational activity for children. Many schools and educational organizations incorporate origami into their curriculum, using it as a way to teach students about geometry, spatial reasoning, and problem-solving.In recent years, the origami rabbit has also gained popularity as a symbol of environmental sustainability. Because it is made entirely from paper, the origami rabbit is a more eco-friendly alternative to traditional toys and decorations. It can be easily recycled orcomposted at the end of its lifespan, making it a more environmentally-friendly choice for those looking to reduce their carbon footprint.Overall, the origami rabbit is a testament to the enduring power of the ancient art of paper folding. Its simple yet elegant form has captivated people around the world, and its cultural significance and practical applications have made it a beloved and enduring symbol of creativity and innovation.Whether you are an experienced origami artist or a complete beginner, the process of creating an origami rabbit can be a deeply rewarding and fulfilling experience. With patience, practice, and a keen eye for detail, anyone can master the art of paper folding and create their own unique and beautiful origami rabbits.。
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law指数定律Recognize识别Attention注意Condition条件Complicated复杂的Whenever无论何时Convenient方便的Suppose假设Notice注意Particular特别的4The binomial expansion二项式展开Binomial二项式Pascal’s triangle杨辉三角(帕斯卡三角形)Immediately直接地Pattern图案Adjacent相邻的Investment投资Interest rate利率Annum年,岁Approximation近似值Ignore忽略Factorial notation阶乘Combination组合Superscript上标Subscript下标Probability可能性Toss投Likelihood可能性Ascending powers升幂Individual个别的Estimation估值Engineering工程学Science科学Percentage error百分误差Microchip微型集成电路片Faulty有缺点的Chip芯片Restrict限制Achieve达到School fair学校园游会Prize奖赏Digit数字Display显示5Sequences and series数列和级数Arithmetic sequence等差数列Arithmetic progression等差数列Common difference公差Arithmetic series等差级数(等差数列前n项求和)Exceed超过Inclusive包含的Stick棒子Pentagon五角形Geometric sequences等比数列Geometric progression等比数列Common ratio公比Converge收敛Alternating sequence交错数列Million百万Geometric series等比级数(等比数列前n项求和)Sum to infinity无限项求和Divergent发散的Convergent收敛的Recurring循环的Sigma notation求和符号Capital首都,大写字母Signify表示Recurrence relations递推关系Previous term前一项First term初项Generate生成,产生Periodic sequence周期数列Period周期Salary薪水Profit利润Predict预言Annual年度的Business商业Financial金融的Advisor顾问Fold折叠Thickness厚度Unrealistic不切实际的Investor投资人Account账户Thereafter以后Deposit存款,定金Wage工资Rise上升Gear齿轮Successive连续的Intermediate中间的Valuable有价值的Commission佣金Insurance保险Policy政策Prospector勘探者Drill钻孔Subsequent随后的Available可获得的Payment报酬Virus病毒Infect传染Diagnose诊断Overfish过度捕捞Chess象棋Chessboard棋盘Sponsored赞助的Polygon多边形Appointment约会,任命6Trigonometric identities and equations三角恒等式和方程Unit circle单位圆Anticlockwise逆时针Quadrant象限Equivalent相等的Equilateral triangle等边三角形Isosceles right-angled triangle等腰直角三角形Identity恒等式Reflex优角(大于180度,在第三、四象限)Principal value主值Inverse trigonometric function反三角函数Justification理由7Differentiation微分Strictly严格地Interval区间Stationary point驻点Local maximum局部最大Greatest value最大值Local minimum局部最小Least value最小值Point of inflection拐点,反曲点Immediate最接近的Vicinity邻近,附近Second derivative二次求导Rate of change改变的快慢Convex凸Concave凹Establish建立,证实Liter升Instant瞬间Tank水槽Cuboid长方体的Sheet薄片Metal金属Sphere球体Displacement位移Cylinder圆柱体Perimeter周长Semicircular半圆的Semicircle半圆Frame框架Split分离,分开Motion运动Damped阻尼Spring弹簧Bent弯的Biscuit饼干Tin罐头Close-fitting紧贴的Lid盖子Thin薄的,瘦的Wastage损耗Obtain获得Percentage百分比Store储存Capacity容量Container容器Calculus微积分学8Integration积分Definite integral定积分Indefinite integral不定积分Whereas反之,然而Upper limit上限Lower limit下限Square bracket中括号Magnitude大小Negligible可忽略的Straddle跨坐Unless除非Complicated复杂的Trapezium梯形Trapezium rule梯形法则Beneath在…下面Strip条,带Boundary边界Adjacent相邻的Improve改善Accuracy精确度Approximation近似值Underestimate低估Overestimate高估Compare比较Pure mathematics3 Common multiple公倍数Improper fraction假分数Partial fractions部分分数Degree次数Modulus function模函数Absolute value绝对值Argument辐角Set notation集合符号Piecewise-defined function分段函数Composite function复合函数Inverse function反函数Secant正割Cosecant余割Cotangent余切Interval区间Symmetry对称性Symmetrical对称的Chord弦Inverse trigonometric function反三角函数Addition formulae加法公式Compound-angle formulae复合角公式Double-angle formulae二倍角公式Round四舍五入Exponential function指数函数Natural logarithms自然对数Trend趋势Outlier极值Chain rule链式法则Product rule乘法法则Quotient rule除法法则Continuous连续的Fixed point iteration定点迭代Successive连续的Converge收敛Staircase diagram梯形图Cobweb diagram网状图Diverge发散Pure mathematics4 Contradiction反驳Assert主张Falsehood虚假Negation反论Prime number质数Split分解Separate独立的Parametric equation参数方程Variable变量Parameter参数Revolution循环Plot绘图Valid有效的As long as只要Condition条件Accurate精确的Ascending上升的Approximation近似值Implicit differentiation隐函数微分Explicitly明确的Implicit隐含的Rate of change变化率Hemisphere半球Cylindrical圆柱形的Conical圆锥形的Concave凹Convex凸Integrand被积函数Integration by substitution换元积分法Integration by part分部积分法Polynomial多项式Separating the variables分离变量General solution通解Boundary condition边界条件Directed line segment有向线段Parallelogram平行四边形Unit vector单位向量Column vector列向量Position vector位置矢量Scalene不等边的Clockwise顺时针Anticlockwise逆时针Coplanar共面的Parallelepiped平行六面体Trisect三等分Hexagon六边形Regular hexagon正六边形Direction vector方向向量Anchor固定Dot 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IntroductionThe ellipse, a fundamental geometric figure that transcends the boundaries of mathematics and permeates various scientific disciplines, is a captivating subject for in-depth analysis. This elegant shape, defined as the locus of points such that the sum of the distances from two fixed points (the foci) is constant, embodies a rich tapestry of properties, applications, and theoretical underpinnings. This essay embarks on a comprehensive, multifaceted exploration of ellipses, delving into their mathematical definition, properties, conic section origins, practical applications, and connections to advanced mathematical concepts.I. Mathematical Definition and PropertiesAn ellipse is a two-dimensional curve characterized by its eccentricity, major axis, minor axis, and foci. Its defining property, as mentioned earlier, is that for any point P on the ellipse, the sum of the distances from P to the two foci, F1 and F2, remains constant:PF1 + PF2 = 2a,where 'a' is the semi-major axis, or half the length of the major axis, which is the longest chord passing through the center of the ellipse. The semi-minor axis, 'b', is the corresponding half-length of the minor axis, perpendicular to the major axis.The eccentricity, denoted by 'e', quantifies the "flatness" of the ellipse, ranging from 0 (a circle) to less than 1 (a non-circular ellipse). It is given by the ratio of the distance between the foci and the length of the major axis:e = c/a = √(a² - b²)/a,where 'c' is the distance between the center and either focus. The area of an ellipse is A = πab, while its perimeter, or circumference, cannot be expressed in a simple closed-form expression but can be approximated using various numerical methods.Ellipses exhibit several notable properties, including:1. Reflective Property: Light emanating from one focus reflects off theellipse and passes through the other focus.2. Conjugate Diameters: Any two diameters of an ellipse that intersect at right angles are called conjugate diameters. Their midpoints lie on a circle called the director circle.3. Harmonic Property: If a tangent and a secant of an ellipse intersect ata point outside the ellipse, then the product of the lengths of the segments of the secant is equal to the square of the length of the tangent segment.II. Origins in Conic SectionsEllipses find their roots in the study of conic sections, dating back to the work of ancient Greek mathematicians such as Apollonius of Perga. A conic section is formed when a plane intersects a double-napped cone at various angles. When the plane is neither parallel nor perpendicular to the cone's axis and intersects both nappes, it generates an ellipse. This perspective provides a geometric intuition for the ellipse's defining property, as the sum of distances from any point on the cutting plane to the cone's apexes is constant.III. Practical ApplicationsEllipses have myriad practical applications across various fields, exemplifying their versatility and significance:A. Astronomy: The orbits of planets and other celestial bodies around the sun or any central mass are elliptical due to the laws of gravitational attraction, as postulated by Johannes Kepler and later incorporated into Isaac Newton's laws of universal gravitation. The Earth's orbit, for instance, is an ellipse with the Sun at one focus.B. Architecture and Engineering: Elliptical shapes are frequently employed in architectural designs for aesthetic appeal and structural efficiency. Examples include elliptical domes, bridges, and arches, such as the famous St. Louis Gateway Arch. In engineering, ellipses are used in the design of reflectors and lenses for optical systems, ensuring optimal light distribution or focusing.C. Image Processing and Computer Graphics: In digital imaging, the Hough transform is a technique used to detect lines, circles, and ellipses in images.Ellipses also feature prominently in computer graphics, particularly in modeling and rendering curved surfaces, texture mapping, and in the design of user interfaces.D. Geographical Information Systems (GIS): Ellipsoidal approximations are used to model the Earth's surface in GIS applications, accounting for the planet's slightly oblate spheroidal shape rather than treating it as a perfect sphere. This is crucial for accurate geodetic calculations, cartography, and satellite navigation systems like GPS.IV. Connections to Advanced Mathematical ConceptsEllipses serve as a gateway to deeper mathematical concepts and theories:A. Elliptic Integrals and Functions: Problems involving arc lengths, areas, and volumes of solids of revolution derived from ellipses lead to the study of elliptic integrals, which are a class of special functions with numerous applications in physics, engineering, and number theory. Elliptic functions, which generalize trigonometric functions, arise as inverses of elliptic integrals and play a vital role in the theory of complex analysis.B. Elliptic Curves: In modern algebraic geometry, elliptic curves are a particular type of smooth, projective curve defined by a cubic equation in two variables. Although they are named due to their superficial resemblance to ellipses, their intrinsic properties and applications, such as in cryptography and number theory (specifically the Birch and Swinnerton-Dyer conjecture), are vastly different.C. General Relativity: In Einstein's general theory of relativity, the path followed by a particle in a gravitational field is described by a geodesic, which in the case of a spherically symmetric mass distribution is an ellipse in the weak-field limit. This provides a direct link between the ellipse's fundamental nature and our understanding of gravity and spacetime curvature.ConclusionThe ellipse, a seemingly simple geometric figure, reveals itself as a profound and multifaceted construct upon closer examination. From its elegantmathematical definition and intriguing properties to its origins in conic sections, practical applications across diverse fields, and connections to advanced mathematical concepts, the ellipse stands as a testament to the beauty and power of mathematics in describing and understanding the world around us. This in-depth analysis underscores the ellipse's enduring significance and invites further exploration of its intricate relationships with various branches of science and mathematics.。
The CSQUARE TransformTom St Denistomstdenis@iahu.caAbstract.In this paper we show how to combine the design conceptsof the SQUARE and CS block ciphers to produce a pseudo-random per-mutation CSQUARE suitable for use in block cipher and hash designwith a very high multi-round trail weight.The new design inherits thehardware efficiency of the SQUARE linear transform pattern as well asthe efficiency of the fast pseudo-Hadamard transform over afinitefield.We demonstrate the DMWT hash function which makes use of our newresults.Keywords.Pseudo-Hadamard Transform,Branch Analysis,Pseudo-Random Permutations.1IntroductionIn the SQUARE block cipher[1]a new technique of combining a Maximum Distance Separable(MDS)code along with the“SQUARE Propagation Pattern”resulted in a design which had a high provable four round differential and linear trail weight.Similarly in the CS-Cipher[3],the concept of a pseudo-Hadamard transform was enhanced to raise the minimal eight round differential and linear trail weight.In this paper we take the results of FPHT analysis in[7]and apply them to the SQUARE propagation pattern to derive a new permutation which has a considerably higher minimal trail weight.Along with our successful design we also demonstrate two similar design constructions which fail to achieve a trail weight greater than the trail weight of the SQUARE design.We shall conclude this paper with a section discussing implementation details and our DMWT hash function.We prove that through our DMWT design any minimal four round trail has a weight of at least144which compares favourably to the minimal trail weight of WHIRLPOOL which is81.In section two we discuss the relevant background required for our new re-sults.Section three discusses our new design as well as the two similar designs. Section four discusses the design justification and sectionfive discusses our new DMWT design.2Background Theory2.1SQUAREThe SQUARE[1]block cipher was a unique approach to cipher design when it wasfirst proposed.It was an efficient design that provided for a high and provable minimal trail weight.The design would later change into the Rijndael block cipher which became the American AES cipher.The relevant design concepts of SQUARE are the following.Letθrepresent a transform which applies a non-linear substitution to all of the coordinates of the input.Letζrepresent a length four MDS code over GF(2)[x].Letγrepresent the sixteen coordinate input organized as a4×4matrix.Then the relevant portions of the SQUARE round function can be expressed as the following.γi+1=ρ(γi,K i):γi×K i→(ζ◦θ◦(γi⊕K i))T(1) While it was not proven in the SQUARE,paper the design has two provable qualities which are proven in the subsequent Rijndael papers.Letβrepresent the branch of theζtransform.Theorem.Every two rounds has at leastβactive columns.Theorem.Every four rounds has at leastβ2active coordinates.For the purposes of this paper we are merely concerned with thefirst theorem. This theorem is trivial to prove.If there are x active columns then through the transposition there shall be one row with at least x active coordinates.Through the subsequentζtransform there shall be the greatest of(β−x,1)active coor-dinates.As a result there are x+β−x=βactive columns.2.2CS-CipherThe CS-Cipher[3]used non-linear multipermutations interconnected in a fashion that promotes fast diffusion.Instead of placing the non-linear substitutions at the boundaries of the linear transform they placed them throughout the transform. In[4],the full eight round trail weight was counted by brute force to prove the security of the design against differential and linear cryptanalysis.This design in particular has several useful properties.1.The round function can be computed in O(log n)time.2.The mixing network is non-linear.3.The branch of the round function is bounded.We use all three properties in our new design by generalizing both the CS-Cipher and SQUARE designs.3New Design-CSQUARE3.1ConstructionOur new design permutes a block of dataγorganized as a square matrix by combining a CS-Cipher style mixing network with the SQUARE propagation pattern.Let n=2k for k≥2represent the width ofγ.Letζrepresent the mixing network made of a H k transform implemented as in[7,Fig.1],with the H1transforms replaced by a non-linear(2,3)-multipermutationθ[6].Letβk represent the branch of theζtransform.We note that with each application ofθwithinζthe inputs are“keyed”by some key K.This allows a Markov chain to be produced throughout the design.Our new design is simply stated asy=ρ(γ,K):γ×K→ ζ◦(ζ◦ζ◦γ)T T(2)Note that the three compositions ofζrequire3k·22k key words to be provided by some form of key schedule.For the purposes of this paper we shall assume some form of suitable key schedule has been provided.This design relies on two theorems to achieve a provable four round trail weight bound.3.2Design TheoryTheorem1.Two compositions ofρwill always have at leastβk active columns. Proof.This proof is simply an adaptation of the two round proof for the SQUARE block cipher.If the input has x active columns then the transposition will have one column with at most x active coordinates.Through the thirdζcomposition of theρtransform there shall be the largest of(βk−x,1)active coordinates. When the matrix is transposed again those active coordinates are placed in unique columns.The second theorem we are concerned with is concretely establishing the two round trail weight ofζ.Theorem2.The two round trail weight for aζtransform of dimension n=2k is at least3·2k−1.A general proof of this theorem is still being developed.However,we can show that the theorem is true for k={1,2,3,4}and we shall provide an argument in favour of the theorem.Case k=1.This case is fairly trivial.The branch ofθis three which immedi-ately yields a minimum two round weight of three.Corollary3.Over two layers ofζany activeθtransform will be directly related to at least three active coordinates.Case k=2.In both rounds at least oneθtransform must be active.As a result at least six active coordinates must be present.Therefore,the theorem is true for k=2since3·2k−1=6.Case k=3.In this case we rely on the branch ofζ3which is provably[7]six. As a result the minimal trail weight is caused by an input weight of two which cause a minimal output weight of four after thefirst round.If the layers of the two rounds are placed end-to-end it is obvious that over thefirst two layers there is at least one activeθ.Over the middle two rounds there are at least two and over the last two at least one more activeθ.Therefore,there are four activeθtransforms which produce the3·2k−1=12active coordinates.Case k=4.This proof is similar to the case of k=3.Again the lowest weight trail is caused by the input weight of two.For thefirst round,thefirst two layers will have at least one activeθand the last two layers will have at least three activeθtransforms.The second round at the very least will be a mirror of thefirst round.In total there shall be at least eight activeθtransforms which achieves the desired3·2k−1=24active coordinates.Conjecture for k≥5.Our conjecture for the general case lies in the topology of the underlying mixing network.In every layer each of theθtransforms are applied to a unique pairing of the input coordinates.As a result,in layer i of a transform,any activeθtransform will be connected to at least two activeθtransforms in at least one of layer i−1or i+1.It seems very plausible that over the k pairs of layers in the two rounds ofζk transforms there are at least2k−1 activeθtransforms.3.3ResultsAs a result of the two theorems the two round trail weight of theρtransform is at least the product of the branch ofζk and the two round trail weight ofζk.Let σn denote the four round trail weight of theρconstruction with a dimension of n×n.σn=6·8k,if n=22k(3)σn=18·8k,if n=22k+1The four round minimal trail weight of the SQUARE design is the branch of the“MixColumn”transform squared.The trail weights for even dimensionζmatch the SQUARE trail weights at approximately the point k=2.541814439 and at the point k=2.169925002for odd dimensionζ.As a result the new design achieves a lower four round trail weight for all dimensions greater than 32×32.3.4Related DesignsThrough the course of this study two other design constructs have been analyzed and both fail to achieve the desired level of trail weight.Thefirst design construct is based on the SQUARE design mixed with the CS-Cipher directly.That is,y=ˆρ1(γ,K):γ×K→(ζ◦γ)T(4) However,this design lacks2an easy method of counting the trail weight over multiple rounds.The second design was a straight adaptation of this design.y=ˆρ2(γ,K):γ×K→(ζ◦ζ◦γ)T(5) However,this design does not enforce a high enough active column count over two rounds.Another modification we considered but rejected for efficiency reasons is the construction:y=ˆρ3(γ,K):γ×K→ ˆζ◦(ζ◦ζ◦γ)T T(6) Whereˆζis a2k dimension MDS code.The resulting four round minimal trail weight of this design would beσ3n.ˆσ3n=3· 4k+2k ,if n=2k(7) Which compares very well against the original SQUARE design.However, theˆρ3approach involves using an MDS code which is something we are striving to avoid since they are slower than theζtransform to implement.Therefore,we rejected this approach for this paper.The approach is still ideal if a very high trail weight is sought.As a remark even the SHARK design[8]which specified that the input be a single column and each round has one MDS transform cannot compete with the minimal trail weight of theˆρ3design.Any four round trail of SHARK must have at leastσS n active coordinates.σS n=2k+1+2,if n=2k(8) Sinceσ3n>σS n and theρ3design requires a square root of the time the SHARK design the SHARK design is not scalable.4Design Justification4.1SecurityThe purpose of this new design is to modify the original SQUARE design and produce a transform which has a higher multi-round trail weight.In doing so we also removed much of the linearity from within the design using the approach ofDimension Our Design:ρSHARK Design60258×814413081628932×32115220501248042253Over all28and216values respectively.4Given a reasonable dimension.ever,the approach is not unreasonable and can be implemented using a very small amount of code and data memory5.5Example ConstructionWe have taken the8×8ρfunction and produced a512−bit message digest function named DMWT.Each coordinate ofγis an eight bit value.The non-linear multipermutationθis constructed by applying the substitution function Σfrom WHIRLPOOL6[2]followed by the H1FPHT over GF(2)[x]/(x8+x4+ x3+x+1).To make the design simpler to implement we break convention and apply theζtransform across a row since the data is loaded in row-major order.Each message is padded with a single1bit followed by enough zero bits to make the message length congruent to448modulo512bits.The original message length is stored in little endian fashion as a64-bit integer at the end of the padding.The512−bit state is organized as64eight bit words S0..63and is initially set to thefirst64values ofΣ.The message is compressed in blocks of64eight bit words M0..63.The compression function is created by the synthetic approach[5, Scheme10].1.M ←M,S ←S2.for x=0to8do(a)M ←ρ(M ,S )(b)S ←ρ(S ,Σ24x)3.M ←ρ(M ,S )4.S←S⊕M⊕MIn step(2.a)the notationΣ24x implies using the values ofΣ24x...24x+63as the key for theρfunction.The key schedule for theρfunction is equally simple. We use the words of the64element key cyclically with the convention thatζis applied to the zeroth rowfirst and theζnetwork is computed in three layers from top to bottom,left to right with the zero’th coordinate to the left.5.1EfficiencySince this design could not be very fast the design was optimized to save space. By using theΣcontents as the initial state and the keys for the key schedule 640bytes of code space were saved.With GCC3.3.2optimizing for space on the AMD Athlon processor the entire hash occupies1,836bytes7.5.2SecuritySynthetic Approach The hash function is actually constructed by using a 512-bit block cipher in chaining mode.In this design we chose“Scheme10”of [5]since it was shown to resist allfive dedicated attacks against hash function constructions.It is also the same construction used in WHIRLPOOL.Differential and Linear Cryptanalysis This design uses ten rounds of theρfunction which means that over eight rounds there are at least2·18·8=288active coordinates.We recall from[2]that theΣwas chosen to have a differential and linear profile maximum of2−5and2−3respectively.As a result the probability and deviation of the best eight round differential and linear attacks would be 2−1440and2−577respectively.The saturation attack was also applied to this design and could not break more than two rounds.Due to the high trail weight along with the reasonably strongΣfunction we reason that the DMWT hash provides sufficient strength to be used as a cryptographic one-way hash function.6ConclusionWe have presented a new data transformation CSQUARE,along with a strong argument concerning the proof of the minimal multi-round trail weight.We have shown that for several dimensions the CSQUARE design yields a higher four round trail weight than the SQUARE design.We have also argued that the CSQUARE design possesses the qualities of speed and space efficiency when implemented in hardware.As a demonstration of the design in use we have presented the DMWT512-bit cryptographic one-way hash function.Based on the minimal trail weight of the CSQUARE design we have proven that DMWT emits no differential or linear bias with a probability above uniformly random.Future work should concentrate on proving the general case of k for the second theorem as well as seeking a more efficient method of implementation.I would like to thank Jean-Luc Cooke for some helpful comments during the initial research period of this project.References[1]J.Daemen and L.Knudsen and V.Rijmen,“The Block Cipher SQUARE”,Fast Software Encryption,v.1267of Lecture Notes in Computer Science,pp.149–165.Springer-Verlag,1997[2]P.Barreto and V.Rijmen,“The WHIRLPOOL Hashing Function”[3]J.Stern and S.Vaudenay.CS-Cipher.In Fifth International Workshop on FastSoftware Encryption,Berlin,Germany,March1998.Springer-Verlag.[4]S.Vaudenay,“On the Security of the CS-Cipher”,Fast Software Encryption,March1999,Springer-Verlag,pp.260-274[5] B.Preneel,aerts and J.Vandewalle,“Hash Functions based on blockciphers:a synthetic approach.”,Crypto’93,Springer-Verlag,1993,pp.368–378 [6]S.Vaudenay,“On the Need for Multipermutations:Cryptanalysis of MD4andSAFER”,LIENS-94-23,November1994[7]T.St Denis,“Fast Pseudo-Hadamard Transforms”,Cryptology ePrint Archive,Report2004-010[8] A.Bossalaers,J.Daemen,B.Preneel,V.Rijmen,E.De Win,“The CipherSHARK”,Fast Software Encryption,pp.99–111,1996.Appendix A-Test VectorsThe following are test vectors for our DMWT hash function.""df5a ae f5a87e7241800b b06d db ce cc1bc64c5f de ed fc bc87760e8c8e70c4cb991f6b1c6a59010520a588594e8993076522e838aa3027ae f0b638dd fe f1b33b60"abc"8e74d6f02f41bc f812d3862a c72a543fb6320d144343c4a90c f6f8bb87f15f9f6b da6b0b432e8a fbe77881b1175c f0007b b3e2e9bf64bf baa2d6f3f3d53e b388"aaaabbbb"x12timese6b1b14498ca f6cac6ed7c c2a3f2b467bb02d8f64e961320820b7d7a de6749981b d185ec ed7e3d059207796c8f ba d5513b e0d9889e ca cc092e85c6a5cf82c861This article was processed using the L A T E X macro package with LLNCS style。