下载文档原格式
高中物理英语词汇机械运mechanical motion [mi'k?nik?l] ['m?u??n]力学mechanics [m?'k?n?ks]质点mass point [m?s] [p?int]参考系reference frame ['refr?ns] [freim]坐标系coordinate system [k?u'?:dineit] ['sist?m]路程path[pɑ:θ］位移displacement[d?s'ple?sm?nt]矢量vector['vekt?]标量scalar['skeil?]速度velocity[vi'l?siti]平均速度average velocity['?v?rid?] [vi'l?siti瞬时速度instantaneous velocity[,?nst?n'teinj?s]速率speed[spi:d]v-t 图象v-t graph[ɡrɑ:f]加速度acceleration [?k,sel?'re???n]普朗克Planck匀变速直线运动uniform variable rectilinear motion['ju:nif?:m] ['v??ri?bl] [,rekti'lini?]初速度initial velocity[i'ni??l] [vi'l?siti]自由落体运动free-fall motion自由落体加速free-fall acceleration[?k,sel?'re???n]重力加速度gravitational acceleration[,ɡr?vi'tei?n?l]伽利略Galileo Galilei力force[f?:s]牛顿Newton['nju:tn]重力gravity['ɡr?viti]重心center of gravity['sent?]万有引力gravitation[,gr?v?'te???n]电磁相互electromagnetic interaction[?,lektr??m?g'net?k]强相互作用strong interaction[,?nt?r'?k??n]弱相互作用weak interaction形变deformation[,di:f?:'me???n,]弹性形变elastic deformation[i'l?stik] [,di:f?:'me???n,]弹性限度elastic limit[i'l?stik] ['limit]弹力elastic force[i'l?stik] [f?:s]劲度系数coefficient of stiffness[,k???'f???nt] ['st?fn?s]胡克定律Hooke law[l?:]摩擦力friction force['frik??n]静摩擦力static frictional force['st?tik] ['frik??n]滑动摩擦力sliding frictional force['slaidi?]动摩擦因数dynamic friction factor[dai'n?mik]合力resultant force[ri'z?lt?nt]分力component force[k?m'p?un?nt]力的合成composition of forces[,k?mp?'zi??n]平行四边形定则parallelogram rule[,p?r?'lel?,gr?m]共点力concurrent forces[k?n'k?:r?nt,]力的分解resolution of force[,rez?'lu:??n]三角形定则triangular rule[tra?'??gj?l?] [ru:l]运动学kinematics[kini'm?tiks]动力学dynamics[dai'n?miks]牛顿第一定律Newton first law['nju:tn] [l?:]惯性inertia [i'n?:?j?]惯性定律law of inertia[i'n?:?j?]质量mass[m?s]惯性系inertial system['sist?m]牛顿第二定律Newton second law单位制system of units国际单位制Le Systeme International Unites SI[,?nt?'n???n?l]作用力action['?k??n]反作用力reaction[ri'?k??n]牛顿第三定律Newton third law超重overweight[,??v?'we?t]失重weightlessness['we?tl?s]误差error['er?]偶然误差accidental error[,?ksi'dentl]系统误差systematic error [,sist?'m?tik]绝对误差absolute error['?bs?lu:t]相对误差relative error['rel?tiv]亚里士多德Aristotle曲线运动curvilinear motion[k?:vi'lini?]基尔霍夫Kirchhoff切线tangent['t?nd??nt]抛体运动projectile motion[pr?'d?ekt?l,]抛物线parabola[p?'r?b?l?]线速度linear velocity['lini?]匀速圆周运动uniform circular motion['ju:nif?:m] ['s?:kjul?]角速度angular velocity['??gj?l?]弧度radian['reidj?n]周期period['pi?ri?d]向心加速度centripetal acceleration[sen'tr?p?tl]向心力centripetal force[sen'tr?p?tl]开普勒Kepler引力常量gravitational constant[,ɡr?vi'tei?n?l]['k?nst?nt]万有引力定律law of universal gravitation[,ju:ni'v?:s?l]第一宇宙速度first cosmic velocity['k?zmik]第二宇宙速度second cosmic velocity第三宇宙速度third cosmic velocity黑洞black hole能力energy['en?d?i]势能potential energy[p?'ten??l]动能kinetic energy[k?'net?k, ka?-]功work[w?:k]焦耳joule[d?u:l]功率power['pau?]瓦特watt['pau?]重力势能gravitational potentialenergy[,ɡr?vi'tei?n?l][p?'ten??l]弹性势能elastic potential energy[i'l?stik] [p?'ten??l]动能定理theorem of kinetic energy['θi:?r?m]机械能mechanical energy[mi'k?nik?l] [k?'net?k]机械能守恒定律law of conservation of mechanical energy[,k?ns?'vei??n] [mi'k?nik?l]能量守恒定律law of energy conservation[,k?ns?'vei??n]亥姆霍兹Helmholtz['helmh?ults]力 force拉力 traction['tr?k??n]力矩 torque[t?:k]动量 momentum[m?u'ment?m]角动量 angular momentum['??gj?l?]振动 vibration[va?'bre???n]振幅 amplitude['?mpl?,tu:d, -,tju:d]波 wave[weiv]驻波 standing wave['st?nd??]震荡 oscillation[,?s?'le???n]相干波 coherent wave[k?u'hi?r?nt]干涉 interference[,?nt?'fi?r?ns]衍射 diffraction[di'fr?k??n]轨道 obital大小 magnatitude方向 direction[di'rek??n]水平 horizental竖直 vertical['v?:tik?l]相互垂直 perpendicular[,p?:p?n'd?kj?l?]坐标 coordinate[k?u'?:dineit]直角坐标系 cersian coordinate system极坐标系 polar coordinate system['p?ul?]弹簧 spring[spri?]球体 sphere[sfi?]环 loop[lu:p]盘型 disc圆柱形 cylinder['silind?]械振动 mechanical vibration [va?'bre???n]简谐振动 simple harmonic oscillation [hɑ:'m?nik]振幅 amplitude ['?mpl?,tu:d, -,tju:d]频率 frequency ['fri:kw?nsi]赫兹 hertz [h?:ts]单摆 simple pendulum ['pendjul?m]受迫振动 forced vibration共振 resonance ['rez?n?ns]机械波 mechanical wave介质 medium ['mi:dj?m]横波 transverse wave [tr?ns'v?:s]纵波 longitudinal wave [l?nd?i'tju:dinl]波长 wavelength ['we?v,le?kθ］超声波 supersonic wave [,sju:p?'s?nik]。
语义分析的一些方法语义分析的一些方法(上篇)•5040语义分析，本文指运用各种机器学习方法，挖掘与学习文本、图片等的深层次概念。
wikipedia上的解释：In machine learning, semantic analysis of a corpus is the task of building structures that approximate concepts from a large set of documents(or images)。
工作这几年，陆陆续续实践过一些项目，有搜索广告，社交广告，微博广告，品牌广告，内容广告等。
要使我们广告平台效益最大化，首先需要理解用户，Context(将展示广告的上下文)和广告，才能将最合适的广告展示给用户。
而这其中，就离不开对用户，对上下文，对广告的语义分析，由此催生了一些子项目，例如文本语义分析，图片语义理解，语义索引，短串语义关联，用户广告语义匹配等。
接下来我将写一写我所认识的语义分析的一些方法，虽说我们在做的时候，效果导向居多，方法理论理解也许并不深入，不过权当个人知识点总结，有任何不当之处请指正，谢谢。
本文主要由以下四部分组成：文本基本处理，文本语义分析，图片语义分析，语义分析小结。
先讲述文本处理的基本方法，这构成了语义分析的基础。
接着分文本和图片两节讲述各自语义分析的一些方法，值得注意的是，虽说分为两节，但文本和图片在语义分析方法上有很多共通与关联。
最后我们简单介绍下语义分析在广点通“用户广告匹配”上的应用，并展望一下未来的语义分析方法。
1 文本基本处理在讲文本语义分析之前，我们先说下文本基本处理，因为它构成了语义分析的基础。
而文本处理有很多方面，考虑到本文主题，这里只介绍中文分词以及Term Weighting。
1.1 中文分词拿到一段文本后，通常情况下，首先要做分词。
分词的方法一般有如下几种：•基于字符串匹配的分词方法。
此方法按照不同的扫描方式，逐个查找词库进行分词。
发电厂：power plant组态：configuration补偿电缆：building out cable电缆敷设：cable laying热继电器：thermorelay配电：distribution就地：on-site电磁阀：electro valve铠装电缆：armored cable校验：checkout冗余：redundancy熔断器：fusible cutout固态电路：solid-state circuit电缆桥架：cable crane span structure分散控制系统DCS：Distributed Control System 数据采集系统（DAS）：Data Acquisition System 模拟量控制系统（MCS）：Mimesis Control System 顺序控制系统（SCS）：Sequences Control System 操作员站（OS）：operator station工程师站（ES）: engineer station盘、箱、柜、台：panel、box、cabinet、board 联锁：interlock可编程控制器（PLC）：programmable logic controller施工图：execution drawing竣工图：completion drawing防爆：explosion proof变送器：transmitter变频器：frequency converter双金属温度计：bimetallic thermometer热电偶：thermocouple热电阻（RTD）: Resistive Thermal Detector 保护套管：adapter pipe差压：differential pressure仪表盘：instrument panel电磁流量计：electromagnetism flowmeter密度计：densimeter电磁波：electromagnetic wave排放：sluice锅炉：boiler进线：incoming line母线：bus line（工作）变压器：（main）transformer直流：direct current手轮：hand wheel控制回路：control circuit减压阀：reducing valve二线制（三线制）：two wire system（three wire system）电磁制动：electromagnetic braking人机界面：human machine interface机组：machine shop端子排：group terminal block接地：connect to earth（earthing）屏蔽：screen（shield）自诊断：self diagnostics电池失效：battery’s out of work高（低）电平：high（low）level耦合：complex coupling电除尘器：electrostatic dust catcher闭锁：lock-out(closure)历史数据的存储和检索（HSR）: Saving and Retrieval of the History data消防：fire protection电磁干扰：electromagnet interference循环冗余校验（CRC）: cyclic redundancy checkout烟气脱硫: flue gas desulfurization脱硫岛:desulfurizing island环氧树脂:Epoxy resin化学耗氧量:chemic consumption of oxygen电导率:Conductance ratio破碎机:Crushing machine湿式球磨机: Wet ball crusher阻燃聚丙稀：Flame retarding polypropylene 水力漩流器：hydrocyclone真空皮带脱水机：Vacuum belt filter鳞片树脂内衬flake resinous liner硫化: sulfidation氧化风机:Oxidizing fan真空泵: Vacuum pump6KV 公用配电屏 6kv station board6KV配电屏 6kv unit boardZ型拉筋 zig-zag rod安培 A: ampere氨 ammonia按钮 push button按钮 pushbutton按钮触点 push contact按时间顺序的 chronological半导体 semiconductor半径的、辐射状的 radial饱和水 saturated water保护和跳闸 protection and trip报警器 annunciator备用 back-up备用 provision备用 reserve比特、位 bit闭环 closed loop避雷器 surge diverter变电站 substation变送器 converter变送器 transmitter变压器 transformer并网 synchronization并行接口 parallel interface波特率 baud rate不导电的、绝缘的 dielectric不断电电源 Uninterruptible power supply(UPS) 不连续的 discrete采样器 pick-ups操作机构 mechanism操作台 the front pedestal侧墙 side wall测试仪表 instrument叉型叶根 multifork root长久的 permanent长期停机 prolong outage厂环 plant-loop厂用变 unit transformer超导体 superconductor超高压 EHV :extra-high voltage成组的、成批的 batch持续时间 duration尺寸 dimension充电器 charger冲动式汽轮机 impulse turbine冲击耐受电压 impulse withstand voltage除盐水 demineralized water除氧器 deaeratorD.A传送、运输 transport串（行接）口 serial interface串行存取 serial access吹灰器 sootblower吹扫 blow/purge垂直的 Vertical磁场作用 the action of a magnetic field磁导率 permeability次烟煤 subbituminous枞树形叶根 fir-tree root错误检验和恢复 error checking and recovery 错误指示器 error detector大规模集成电路 large scale integrate circuit 大修 overhaul单向流动 single-flow氮 nitrogen导纳 conductance导体 conductor导叶 Vane低压厂用变 sub-distribution transformer低压缸 low pressure cylinder/casing(LP)点火 light/ignite点火器 igniter电厂 power plant电磁 Solenoid电导率 conductibility电动操纵的 motor-operated电动机控制中心 MMC: motor control center电动机启动装置 motor starter电动液压的 electro-hydraulic电感电流 inductive current电抗 reactance电缆 cable电流互感器 CT :current transformer电气设备 electrical equipment/apparatus电容 capacitance电容电流 capacitive current电容器 capacitor电枢 armature电网 grid电网 network电涡流式检测器eddy current proximity detector电压互感器PT: potential /voltage transformer电压转换器 electric pressure converter电压自由触点 volt free contact电源 power supplies电站（水） power station电阻 resistance吊耳 lug调节、调制 Modulation调速器 governor调制解调 modulation-demodulation顶点 apex顶棚管 roof tube定位 orientation定子 stator定子机座 stator frame动稳定 dynamic stability动叶片 moving blades/ blading独立存在的 autonomous独立的 free standing端子、接线柱 instrument terminal端子箱、出线盒 terminal box断路器 circuit breaker锻造 casting对称度 symmetry对流烟道 convection pass多功能处理器 Multi Function Process(MFP)多项式 order polynomial额定负荷 ECR:economic continuous rating二极管 diode二进制单元 binary cell二进制的 binary二进制计数器 binary counter发电机 generator发光二极管 LED反动式汽轮机 reaction turbine反馈 feed back反相显示 reverse video沸腾 boil分辨率 resolution分层（级）的 hierarchical分隔墙 division wall分接头 tap分接头绕组 tapping winding分散控制系统 distribute control system(DCS) 分析基 air dry分压器 diverter粉状燃料 ground coal /pulverized fuel风道 duct风箱 wind box伏特 V: volt符号字符 character幅度 amplitude辅助的 auxiliary负压燃烧 suction firing附属部分 annex复制的、备用的 duplicate副励磁机 pilot exciter改造 alteration干式电缆 dry -core cable干燥基 dry感抗 inductance感应的 inductive高级的、先进的 sophisticated高压缸 high pressure cylinder/casing(HP)隔板 diaphragm 隔间 bay隔离开关 disconnecter给煤机 coal feeder给煤机转速信号 feeder speed跟随 shadow工程单位 engineering unit工业分析 proximate analysis工业锅炉 industrial boiler公差 tolerance公用锅炉 utility boiler公用系统 common service system鼓风机 forced draft fan固定碳 fixed carbon关合电流 making current管板 tube sheet管道 pipe管排 tube bundle管形的 tubular管子 tube管座 tube seat光电 photo-electric光洁度 finish硅 silicon锅炉 boiler/steam generator锅炉自动控制 Automatic Boiler Controls 过程处理单元 Process Control Unit (PCU) 过冷水 subcooled water过量空气 excess air过热器 superheater毫伏 millivolt褐煤 brown coal/lignite横向的 transverse后端、末端 rear end户内的 indoor滑环 Slipping化石燃料 fossil fuel还原气氛 reducing condition/atmosphere 环状的 annular灰分 ash挥发分 volatile机柜 cubical机座 frame级间漏汽 interstage leakage集控室 central control room (CCR)记录、日志 log架空的 overhead架空输电线 overhead transmission line 间隙 clearance兼容性、相容性 compatibility监测 monitoring监督管理 supervise监控方式 monitor mode监控器 monitor/monitor unit减温器 Attemperator检验 calibration交流电 alternating current接口 interface节点 node截止阀 stop/emergency valve紧急的应力 emergency stress经由 Via静叶片 stationary blades/ blading绝缘 galvanic isolation绝缘子 insulator开断 interruption开断电流 breaking current开关 switcher开关柜 switch cabinet开关柜 Switchgear开关组 switch block开环 open loop开环 open-cycle可编程逻辑控制器programmable logic controller(PLC)可编程只读存储器programmable read only memory(PROM)可靠性 reliability可燃基 dry and ash free可视通讯 visual communication空气断路器 air circuit breaker空气绝缘的 air-insulated空气预热器 air preheater控制按钮 control button(knob)控制精度 control accuracy控制屏 the operations panel控制器 controller控制室 the control room控制台 control console(desk)控制线圈 search coil控制仪表系统control and instrumentation(C&I)控制作用 control action浪涌 surge冷端补偿 cold junction compensation励磁 excite励磁机 exciter 例外报告 exception report联氨 hydrazine联锁 interlock联锁触点 interlocking contact联锁开关系统 interlocking switch system联锁信号 interlocking signal联箱 header联轴器 coupling裂纹 crack/cracking临界压力 critical pressure令牌 token流量 flow rate流量计 flow meter硫 sulfur/sulphur六氟化硫 sulphur hexa fluoride露点 the dew point temperature炉膛 furnace螺钉 screw毛胚 blank毛胚 roll媒介、介质 medium煤 coal煤粉燃烧器 PF burner/pulverized fuel burner 密度热电阻 density RTD灭弧 quench模块 workhouse模拟量 analogue模拟图 Mimic模拟子模块 ASM模数转换 Analogue to Digital conversion膜式壁 membrane panel/wall磨煤机 pulverizer/mill母线 busbar/bus内部的 internally内缸 inner casing能共存的、兼容的 compatible能量管接头 energy stud/stub凝结 condensate欧姆 ohm排污管 blowdown pipe盘车装置 turning gear配电 distribution配电盘、屏、板 panel膨胀 expansion疲劳、软化 fatigue偏心度 eccentricity平方根 square root平面 plane平直度 alignment齐纳二极管 Zener diode启备变 start up/standby transformer /启动 start up启动控制阀 pneumatic pilot valve气态 gaseous汽包 steam drum汽封片 gland segment/packing汽缸 cylinder汽机监视仪表turbine supervisory instrument(TIS)汽轮机 turbine汽泡户外的 bubble outdoor汽水混合物 steam-water -mixture千伏 kilo-volt前后墙 front/rear wall /强迫循环 forced/pumped circulation切除、切断、脱扣 trip氢 hydrogen求出的数量 evaluate全功能组件 complete functional set全貌、总的看法 overview燃料烟道 fuel /flue /燃烧器 burner扰动 intervetion/disturbing/bump绕组 winding热电厂 thermal power plant热电偶 thermocouple热电偶 thermocouple热工仪表 thermodynamic instrumentation热量加热 heat /热效率 thermal efficiency热应力分析 thermal stress analysis容量 capacity熔断 blow熔断器 fuse冗余测试 redundancy testing冗余的 redundancy冗余位 redundancy bit蠕变 creep散热片 cooling fin上半部 the top half蛇形管 serpentine tube设备、工具 facility省煤器 economizer湿蒸汽 wet-steam十二进制 duodecimal十进制的 decimal 十六进制 hexadecimal石油 oil使分流 shunt使完整 integration视频 visual frequency视像扫描器 visual scanner试运行 Commission试运行 commissioning operation疏水 Drain疏水管 drain pipe树脂浇注变压器 cast resin transformer 数字显示 digit display数字信号 digit signal双层缸结构 double shell structure双列端子排 two-tier terminals双向流动 double-flow双重的固态 dual solid水 water水电站 hydraulic power plant水分 moisture水冷壁 furnace tube水平的 horizontal水平接合面 the horizontal joint水位 water level水位计 gauge glass水压实验 hydrostatic test水蒸气 steam/water vapor酸洗 acid cleaning算法 algorithms榫头 tenon探针 probe碳 carbon天然气 natural gas条形 bar条形图 bargraph铁素体 mill铁芯 core停机 shut down停运 outage通道、信道 channel同类的 peer推力轴承 thrust bearing瓦特 W: watt外缸 outer casing网络接口子模块 INNIS微型调速器 microgovernor围带 shroud/shrouding温度 temperature文件缓冲器 archive buffer稳定性 stabilization稳态 steady-state无烟煤 anthracite物品、元件 item误差率 error rate误动作 malfunction熄灭、灭火 extinction铣制 forging系统 scheme: system下半部 the bottom half线圈 coil线性差动变压器 linear variable differential transformer (LVDT)线性化 linearization相变 phase change相互 interconnection相互隔离 isolate相同的 Uniform :the same消耗 consumption销钉 dowel协调的 harmonious协调控制系统coordination control system(CCS)信号调节 signal conditioning星型 palm terminal星型连接 connected in star形凹槽 notch V压力 pressure压力表 pressure meter烟道 flue烟煤 bituminous烟气 flue gas烟气热风器 gas air header氧 oxygen氧化气氛 oxidized condition/atmosphere叶顶 tip叶根 root叶轮 impeller/wheel/disk液态 liquid一氧化碳 monoxide一组 suite仪表量程 instrument range仪表灵敏度 instrument sensitivity仪表校正 instrument correction仪器盘 instrument board仪器仪表板 facia/fascia引风机 induced draft fan 应用基 as received永久磁铁 permanent magnet油浸式电缆 oiled-cable油枕 expansion tank有载调压的 load tap-changing元素分析 ultimate analysis原煤斗 coal bunker圆形的 circular圆柱形的 cylindrical圆锥形的 conical运行操作 operation /运行工况 operation condition再热器 reheater兆伏安 MVA: mega volt-ampere真空断路器 vacuum contactor振动 Vibration蒸发 evaporate蒸汽热风器 steam air header整流 rectify正压燃烧 pressure firing支持轴承 journal bearing执行机构 actuator直观显示元件 visual display unit (VDU)直观显示终端visual (inquiry)display terminal直流电阻 D.C. resistance质量 quality中心度、同心度 concentricity中心线 centerline中性点 neutral point中压缸intermediate pressure cylinder/casing(IP)终端、端子 terminal终端设备 terminal device重力 gravity周围的 circumferential轴 shaft轴承座 bearing house轴承座 pedestal轴承座 pedestal轴环 collar轴瓦 bearing pad轴向的 axial主变 generator transformer主要辅机 major pant item主蒸汽 live steam煮炉 Boil out铸造 governing valve转存 dump转换开关 inverter转接器、接头、 adapter转子 Rotor转子 rotor锥体 cone锥体 pyramid子模块 slave module子系统 sub system自动控制系统 automatic control system自然循环 natural/thermal circulation总线接口模块 bus interface module(BIM)纵向的 longitudinal阻波器 trap组态 configure最新发展水平的 state-of the-art最优控制 optimum control6KV 公用配电屏 6kv station board6KV配电屏 6kv unit boardZ型拉筋 zig-zag rod安培 A: ampere氨 ammonia按钮 push button按钮 pushbutton按钮触点 push contact按时间顺序的 chronological半导体 semiconductor半径的、辐射状的 radial饱和水 saturated water保护和跳闸 protection and trip报警器 annunciator备用 back-up备用 provision备用 reserve比特、位 bit闭环 closed loop避雷器 surge diverter变电站 substation变送器 converter变送器 transmitter变压器 transformer并网 synchronization并行接口 parallel interface波特率 baud rate不导电的、绝缘的 dielectric不断电电源 Uninterruptible power supply(UPS) 不连续的 discrete采样器 pick-ups 操作机构 mechanism操作台 the front pedestal更多分类词汇请访问侧墙 side wall测试仪表 instrument叉型叶根 multifork root长久的 permanent长期停机 prolong outage厂环 plant-loop厂用变 unit transformer超导体 superconductor超高压 EHV :extra-high voltage成组的、成批的 batch持续时间 duration尺寸 dimension充电器 charger冲动式汽轮机 impulse turbine冲击耐受电压 impulse withstand voltage除盐水 demineralized water除氧器 deaeratorD.A传送、运输 transport串（行接）口 serial interface串行存取 serial access吹灰器 sootblower吹扫 blow/purge垂直的 Vertical磁场作用 the action of a magnetic field磁导率 permeability次烟煤 subbituminous枞树形叶根 fir-tree root错误检验和恢复 error checking and recovery 错误指示器 error detector大规模集成电路 large scale integrate circuit 大修 overhaul单向流动 single-flow氮 nitrogen导纳 conductance导体 conductor导叶 Vane低压厂用变 sub-distribution transformer低压缸 low pressure cylinder/casing(LP)点火 light/ignite点火器 igniter电厂 power plant电磁 Solenoid电导率 conductibility电动操纵的 motor-operated电动机控制中心 MMC: motor control center 电动机启动装置 motor starter电动液压的 electro-hydraulic电感电流 inductive current电抗 reactance电缆 cable电流互感器 CT :current transformer电气设备 electrical equipment/apparatus电容 capacitance电容电流 capacitive current电容器 capacitor电枢 armature电网 grid电网 network电涡流式检测器eddy current proximity detector电压互感器PT: potential /voltage transformer电压转换器 electric pressure converter电压自由触点 volt free contact电源 power supplies电站（水） power station电阻 resistance吊耳 lug调节、调制 Modulation调速器 governor调制解调 modulation-demodulation顶点 apex顶棚管 roof tube定位 orientation定子 stator定子机座 stator frame动稳定 dynamic stability动叶片 moving blades/ blading独立存在的 autonomous独立的 free standing端子、接线柱 instrument terminal端子箱、出线盒 terminal box断路器 circuit breaker锻造 casting对称度 symmetry对流烟道 convection pass多功能处理器 Multi Function Process(MFP) 多项式 order polynomial额定负荷 ECR:economic continuous rating二极管 diode 二进制单元 binary cell二进制的 binary二进制计数器 binary counter发电机 generator发光二极管 LED反动式汽轮机 reaction turbine反馈 feed back反相显示 reverse video沸腾 boil分辨率 resolution分层（级）的 hierarchical分隔墙 division wall分接头 tap分接头绕组 tapping winding分散控制系统 distribute control system(DCS) 分析基 air dry分压器 diverter粉状燃料 ground coal /pulverized fuel风道 duct风箱 wind box伏特 V: volt符号字符 character幅度 amplitude辅助的 auxiliary负压燃烧 suction firing附属部分 annex复制的、备用的 duplicate副励磁机 pilot exciter改造 alteration干式电缆 dry -core cable干燥基 dry感抗 inductance感应的 inductive高级的、先进的 sophisticated高压缸 high pressure cylinder/casing(HP)隔板 diaphragm隔间 bay隔离开关 disconnecter给煤机 coal feeder给煤机转速信号 feeder speed跟随 shadow工程单位 engineering unit工业分析 proximate analysis工业锅炉 industrial boiler公差 tolerance公用锅炉 utility boiler公用系统 common s控制作用 control action浪涌 surge冷端补偿 cold junction compensation励磁 excite励磁机 exciter例外报告 exception report联氨 hydrazine联锁 interlock联锁触点 interlocking contact联锁开关系统 interlocking switch system联锁信号 interlocking signal联箱 header联轴器 coupling裂纹 crack/cracking临界压力 critical pressure令牌 token流量 flow rate流量计 flow meter硫 sulfur/sulphur六氟化硫 sulphur hexa fluoride露点 the dew point temperature炉膛 furnace螺钉 screw毛胚 blank毛胚 roll媒介、介质 medium煤 coal煤粉燃烧器 PF burner/pulverized fuel burner 密度热电阻 density RTD灭弧 quench模块 workhouse模拟量 analogue模拟图 Mimic模拟子模块 ASM模数转换 Analogue to Digital conversion膜式壁 membrane panel/wall磨煤机 pulverizer/mill母线 busbar/bus内部的 internally内缸 inner casing能共存的、兼容的 compatible 能量管接头 energy stud/stub凝结 condensate欧姆 ohm排污管 blowdown pipe盘车装置 turning gear配电 distribution配电盘、屏、板 panel膨胀 expansion疲劳、软化 fatigue偏心度 eccentricity平方根 square root平面 plane平直度 alignment齐纳二极管 Zener diode启备变 start up/standby transformer /启动 start up启动控制阀 pneumatic pilot valve气态 gaseous汽包 steam drum汽封片 gland segment/packing汽缸 cylinder汽机监视仪表turbine supervisory instrument(TIS)汽轮机 turbine汽泡户外的 bubble outdoor汽水混合物 steam-water -mixture千伏 kilo-volt前后墙 front/rear wall /强迫循环 forced/pumped circulation切除、切断、脱扣 trip氢 hydrogen求出的数量 evaluate全功能组件 complete functional set全貌、总的看法 overview燃料烟道 fuel /flue /燃烧器 burner扰动 intervetion/disturbing/bump绕组 winding热电厂 thermal power plant热电偶 thermocouple热电偶 thermocouple热工仪表 thermodynamic instrumentation热量加热 heat /热效率 thermal efficiency热应力分析 thermal stress analysis容量 capacity熔断 blow熔断器 fuse冗余测试 redundancy testing冗余的 redundancy冗余位 redundancy bit蠕变 creep散热片 cooling fin上半部 the top half蛇形管 serpentine tube设备、工具 facility省煤器 economizer湿蒸汽 wet-steam十二进制 duodecimal十进制的 decimal十六进制 hexadecimal使分流 shunt使完整 integration视频 visual frequency视像扫描器 visual scanner试运行 Commission试运行 commissioning operation疏水 Drain疏水管 drain pipe树脂浇注变压器 cast resin transformer 数字显示 digit display数字信号 digit signal双层缸结构 double shell structure双列端子排 two-tier terminals双向流动 double-flow双重的固态 dual solid水 water水电站 hydraulic power plant水分 moisture水冷壁 furnace tube水平的 horizontal水平接合面 the horizontal joint水位 water level水位计 gauge glass水压实验 hydrostatic test水蒸气 steam/water vapor酸洗 acid cleaning算法 algorithms榫头 tenon探针 probe碳 carbon天然气 natural gas条形 bar条形图 bargraph铁素体 mill铁芯 core 停机 shut down停运 outage通道、信道 channel同类的 peer推力轴承 thrust bearing瓦特 W: watt外缸 outer casing网络接口子模块 INNIS微型调速器 microgovernor围带 shroud/shrouding温度 temperature文件缓冲器 archive buffer稳定性 stabilization稳态 steady-state无烟煤 anthracite物品、元件 item误差率 error rate误动作 malfunction熄灭、灭火 extinction铣制 forging系统 scheme: system下半部 the bottom half线圈 coil线性差动变压器 linear variable differential transformer (LVDT)线性化 linearization相变 phase change相互 interconnection相互隔离 isolate相同的 Uniform :the same消耗 consumption销钉 dowel协调的 harmonious协调控制系统coordination control system(CCS)信号调节 signal conditioning星型 palm terminal星型连接 connected in star形凹槽 notch V压力 pressure压力表 pressure meter烟道 flue烟煤 bituminous烟气 flue gas烟气热风器 gas air header氧 oxygen氧化。
专利名称：Distributed simulation发明人：Oleg Wasynczuk,Charles E. Lucas,Eric A.Walters,Juri V. Jatskevich申请号：US09884528申请日：20010619公开号：US07490029B2公开日：20090210专利内容由知识产权出版社提供专利附图：摘要：A method and apparatus are presented to facilitate simulation of complex systems on multiple computing devices. Model authors can specify state-related information to be exported for viewing or access by other applications and models.Subsystem models may be written to enable connection with other subsystem models via controlled interfaces, such as by defining state-related information for export and providing for a particular use of data imported from other models to which a subsystem model is connected. In some embodiments, a consistent distributed simulation API enables cross-platform, multi-device simulation of complex systems, wherein the proprietor of each subsystem simulation can keep its implementation secret but accessible to others.申请人：Oleg Wasynczuk,Charles E. Lucas,Eric A. Walters,Juri V. Jatskevich地址：West Lafayette IN US,Lafayette IN US,Brownsburg IN US,Lafayette IN US国籍：US,US,US,US代理机构：Woodward, Emhardt, Moriarty, McNett & Henry LLP更多信息请下载全文后查看。
版权所有，违者必究！！中文版低温等离子体作业一. 氩等离子体密度103210n cm -=⨯, 电子温度 1.0e T eV =, 离子温度0.026i T eV =, 存在恒定均匀磁场B = 800 Gauss, 求 （1） 德拜半径；（2） 电子等离子体频率和离子等离子体频率； （3） 电子回旋频率和离子回旋频率； （4） 电子回旋半径和离子回旋半径。
解：1、1/2302()8.310()e iD e i T T mm T T neελ-==⨯+， 2、氩原子量为40，221/21/200()8.0,()29pe pi e ine ne GHz MHz m m ωωεε====，3、14,0.19e i e ieB eB GHz MHz m m Ω==Ω== 4、设粒子运动与磁场垂直24.210, 1.3e e i i ce ci m v m v r mm r mm qB qB -===⨯===二、一个长度为2L 的柱对称磁镜约束装置，沿轴线磁场分布为220()(1/)B z B z L =+，并满足空间缓变条件。
求：（1）带电粒子能被约束住需满足的条件。
（2）估计逃逸粒子占全部粒子的比例。
解：1、由B(z)分布，可以求出02m B B =，由磁矩守恒得22001122m mmv mv B B ⊥⊥=，即0m v ⊥⊥= （1） 当粒子能被约束时，由粒子能量守恒有0m v v ⊥≥，因此带电粒子能被约束住的条件是在磁镜中央，粒子速度满足002v v ⊥≥2、逃逸粒子百分比201sin 129.3%2P d d πθϕθθπ===⎰⎰ （2）三、 在高频电场0cos E E t ω=中，仅考虑电子与中性粒子的弹性碰撞，并且碰撞频率/t t ea ea v νλ=正比于速度。
求电子的速度分布函数，电子平均动能，并说明当t ea ων>>时，电子遵守麦克斯韦尔分布。
解：课件6.6节。
Gateway to control countless popular productsDesigned from the ground up to be a seamless part of URC’s Total Control® system, the TRF-ZW1 provides a gate-way to allow control of Z-Wave®-enabled products. Enjoy control of Z-Wave door locks, lighting and more from any Total Control interface including remotes, keypads and smart phones or tablets. This piece opens up Total Controlto the broadly appeal-ing world of Z-Wave integration providing yet another avenue to take total control of more components in and around your workplace with URC.TRF-ZW1TOTAL CONTROL Z-WAVE® EXTENDERCOMMERCIALTRF-ZW1TOTAL CONTROL Z-WAVE EXTENDERKeep your eye on things at workUsing URC’s handheld remotes or brilliant in-wall touch-screens, you can securely lock and unlock the doors or adjust lighting while at work. Or, using your iPad® or iPhone®, you can check on things and adjust them from afar. It’s the ideal solution for true access control. Just imagine the luxury of a completely wired o ce where all electronics talk to each other, and to you, via URC Total Control interfaces for the workplace of the future.© 2014 Universal Remote Control, Inc.WE GIVE YOU TOTAL CONTROL.Universal Remote Control, Inc. 500 Mamaroneck Ave. Harrison, NY 10528Phone (914) 835-4484 Fax (914) 835-4532 TRF-ZW1 COMMERCIAL JUNE 2014TRF-ZW1 operates on the Z-Wave frequency that’s used in the USA, Canada and Mexico (908.4 MHz). TRF-ZW is sold separately from Total Control system and interface products. Speci cations and screen designs are subject to change without notice. Universal Remote Control and Total Control are trademarks of Universal Remote Control, Inc. All other trademarks are the property of their respective owners.Two-way control of Z-Wave locks and lighting and one-way control for all Z-Wave-enabled products.Compatible with URC’s Total Control product lineSystem Integration with URC ProductsPlease note: URC two-way communication modules with speci c Z-Wave-enabled products are added in an ongoing way. To nd out if a speci c model or category of products is compatible using two-way control, please check with your URC Product Specialist, Salesperson or Tech Support. Not compatible with URC’s Complete Control™ product line.。
Spin-orbital interaction尤其是，我们讨论了在偏振螺旋光束中的纵向和轨道角动量（和平均角动量方向平行）。
然后，我们集中讨论横向（和平均角动量方向正交）自旋轨道角动量（原理和实验上都得到了讨论和观察到）。
横向自旋轨道角动量在：1、倏逝波（evanescent waves），2、交界面场（interference fields），3、聚焦光束中（focused beams）尤其是，倏逝波可以在交界面产生robust自旋轨道耦合效应（称为光的量子自旋霍尔效应）横向轨道角动量：分为extrinsic 和intrinsic.这两种轨道角动量分别由光束的空间（偏移）相移和洛伦茨根（Lotrentz boosts）产生。
The former (extrinsic) case is related to transverse shifts of paraxial beams, and it plays an important role in the spin Hall effect of light. The latter (intrinsic) case is realized in polychromatic spatio-temporal beams, which can be obtained, e.g., via a transverse Lorentz boost to a moving reference frame.目录1、简介。
22、自旋轨道角动量的基本性质。
33、横向自旋角动量。
114、横向轨道角动量。
265、结论。
33自旋角动量由圆偏振光束产生左旋右旋圆偏振光分别对应：光子的正的和负的螺旋系数（圆偏振度）：σ=±1。
光的自旋角动量和光的传播方向是一致的。
Spin AM<S>=σ<k>/k(k为平均波矢)沿着光束轴的轨道角动量：<L>=l<k>/k, l光涡流的量子数（拓扑电流）。
a r X i v :h e p -p h /9706526v 1 27 J u n 1997FERMILAB-PUB-97/207-TW and Z transverse momentum distributions:resummation in q T-spaceR.K.Ellis and Siniˇs a VeseliTheory Group,Fermi National Accelerator Laboratory,P.O.Box 500,Batavia,IL 60510February 1,2008AbstractWe describe an alternative approach to the prediction of W and Z transverse momentum distributions based on an extended version of the DDT formula.The resummation of large logarithms,mandatory at small q T ,is performed in q T -space,rather than in the impact parameter b .The leading,next-to-leading and next-to-next-to-leading towers of logarithms are identical in the b -space and q T -space approaches.We argue that these terms are sufficient for W and Z production in the region in which perturbation theory can be trusted.Direct resummation in q T -space provides a unified description of vector boson transverse momentum distributions valid at both large and small q T .1IntroductionWe re-examine the transverse momentum distributions of vector bosons,in view of thelarge data samples expected at the Tevatron.In p ¯p collisions at√dQ 2dq 2Tdy =σ0dq 2Tf q/A (x A ,q T )f ¯q /B (x B ,q T )exp[T DDT (q T ,Q )]+(q ↔¯q),(1)where T is a leading log Sudakovform-factor,1T DDT (q T ,Q )=−Q 2q 2Td ¯µ2π4¯µ2−31Other notation will be defined in the body of the paper.2See,for example,Ref.[4].2the remarkable consequence that the cross section at q T=0is calculable for very large Q[5,6].3Nevertheless,in practice the b-space formalism has certain disadvantages.Since the cross section is given as a Fourier integral in b which extends from0to∞,one cannot make theoretical predictions for any q T without having a prescription for dealing with the non-perturbative region of large b.This problem can be solved by introducing an additional non-perturbative form factor(to be determined from experiment),but that also leads to unphysical behaviour of the cross section at large q T,where one should recover the ordinary perturbation theory result.These points will be further discussed later in the text.Clearly,if one could perform the Fourier integral in b analytically and thus obtain an expression for the cross section in q T-space,the above problems would be solved.A model for the non-perturbative region would have to be introduced only at the very lowest values of q T,and one would have a unified description of vector boson transverse momentum distributions valid at both small and large q T.In this paper we present an approach to resummation in q T-space,which is based on an extended version of the DDT formula.The b-space formalism[6]-[14]resums the): contributions to the cross section from the following towers of logarithms(L=ln Q2/q2T1L:αj S L2j−2,q2T1NNL:αj S L2j−4.(3)q2TOur extended DDT expression agrees with the b-space results for all but the NNNL series.However,for vector bosons with masses less than M Z,wefind that the NNNL series is numerically unimportant for q T>3GeV.Furthermore,a specific choice of coefficients in the q T-space Sudakov form factor allows us to absorb thefirst term in the NNNL tower of logarithms,and to obtain exact agreement with resummation in b-space to O(α2S).Based on these results,we argue that the q T-space approach preserves almost all the reliable features of the b-space formalism,4and that it also has certain practical advantages:•We avoid numerical pathologies in the matching,caused by combining results from b-space and q T-space.Although the matching is formally included in the b-space method[7,10,12,13],the cross section is not correctly calculated for q T≥Q/2.The cross section in this region is the result of a delicate cancellation between the resummed andfinite pieces.The slightly different treatment of the two terms is sufficient to upset the cancellation.In contrast,the matching works well in q T-space,leading to a unified description of the q T and y distributions valid for all q T.•We need to introduce a model only at the very lowest values of q T.•We have the practical advantage that we avoid both the numerical Fourier transform and multiple evaluations of the structure functions at each value of q T.A complete explanation of these points will be found later in the paper.It is important to emphasize here we are not challenging the theoretical importance of the b-space formalism,which leads to interesting results,particularly about the production of very massive bosons.Nevertheless,it is our opinion that in practice the extended DDT approach is sufficient for the theoretical description of the W and Z production.The rest of the paper is organized as follows:in Section2we review the b-space re-summation.In Section3we derive an extended version of the DDT expression,whichforms the basis of our approach.Section4contains comparison of the perturbative Su-dakov form factors in the q T-space and b-space formalisms,and shows that in the region where the latter is reliable it is essentially identical with the former.We also present a prescription for dealing with the non-perturbative region of low q T,and compare our results with typical b-space calculations.Our conclusions are given in Section5,while Appendix A contains the saddle point evaluation of the b-space expression for the cross section at q T=0.2Resummation formalism in b-spaceThe general expression for the resummed differential cross section for vector boson pro-duction in hadronic collisions may be written in the formdσ(AB→V(→l¯l′)X)Q228NπSS is the total hadron-hadron center-of-mass energy,whileθandφrefer to the lepton polar and azimuthal angles in the Collins-Soper(CS)frame[15].The mass and width of the vector boson are denoted by M V andΓV.The functions Y r and Y f stand for the resummed andfinite parts of the cross section,respectively.As the details of thefinite part are not important for the subsequent discussion,we review here only the resummed part,and refer the reader to Ref.[13]for the complete description of O(αS)finite part.The resummed part of the cross section is given as the Fourier integral over the impact parameter b,5Y r(q2,Q2,y,θ)=Θ(Q2−q2T)1T5The prime on the sum in Eq.(5)indicates that gluons are excluded from the summation.5×W ab(Q,b∗,θ)f′a/A(x A,b0b∗),(5) where the variables x A and x B are given in terms of the lepton pair mass Q and rapidityy asx A=QSexp(y),x B=QSexp(−y).(6)The modified parton structure functions in Eq.(5),f′,are related to thezC ac x A2−4)δ(1−z) ,(8)C ag(z,µ)=¯αS(µ)T R 2z(1−z) .(9) Here we have introduced¯αS(µ)=αS(µ)¯µ2 lnQ2The first two coefficients in the expansion of A and B are known [16,17]:A (1)=2C F ,A(2)=2C FN (676)−104−12ζ(3)+C F N 1112+6ζ(3)+C F T R n f 179π2.(14)One of the main advantages of the b -space resummation formalism is that the simple form for S (b,Q )as given in Eq.(12),remains valid to all orders in perturbation theory [6].In addition,as mentioned above,for very large values of the vector boson mass the b -space formulae make definite predictions for the q T =0behaviour of the cross section [5,6].Unfortunately,the practical implementation of the b -space formulae presents some difficulties.The b -space integral in the Bessel transform in Eq.(5)extends from 0to ∞,which means that one has to find a way to deal with the non-perturbative region where b is large.That problem is usually circumvented by evaluating W and the parton structure functions atb ∗=b 1+(b/b lim)2,(15)which never exceeds the cut-offvalue b lim ,and also by introducing an additional function F NP ,which represents the non-perturbative (large b )part of the Sudakov form factor,to be determined from experiment [6].This is usually done by assuming a particular functional form for F NP which involves several parameters that can be adjusted in order to give the best possible description of experimental data.The specific choice of the functional form for F NP is a matter of debate [9,11,13],but we will not discuss it further here.The point which we would like to emphasize here is that without introducing b ∗and F NP one would not be able to make theoretical predictions for any value of q T ,even in the large q T region where perturbation theory is expected to work well.7Another problem which occurs in the b-space resummation formalism is the transition between the low and the high q T regions.At large q T the resummed part is well represented by thefirst few terms in its perturbative expansion.When the resummed part Y r is combined with Y f one formally recovers the perturbation theory result.However,the cancellation at large q T is quite delicate and is compromised by the non-perturbative function which acts only on Y r.We illustrate the problem in Figure1,6which compares the O(αS)perturbation theory result for dσ/dq T in W++W−production at the Fermilab Tevatron,to the theoretical prediction obtained from the b-space resummation(Eqs.(4) and(5)).7Even though by carefully matching the low and high q T regions one can reduce theo-retical errors and produce smoother transverse momentum distributions,matching is still bound to fail eventually,and one is forced to switch to the pure perturbative result at some q T[10].This procedure inevitably leads to discontinuous q T distributions,which are clearly unphysical.If one couldfind a q T-space expression for Y r,both of the above problems would be solved:just as for the conventional perturbation theory,theoretical predictions could be made without any smearing or additional functions,at least for values of q T not too close to zero.Also,since Y r and Y f would both be calculated in q T-space,the cancellation between the resummed part and subtractions from thefinite part would be explicit,and matching of Y r+Y f onto the perturbative result at large q T would be manifest.With this motivation we consider the derivation of q T-space equivalent of Eq.(5)in the following section.3Resummation in q T-space:extended DDT formulaFor the sake of simplicity we discuss only the resummed part of the non-singlet (NS)cross section for the process AB →γ∗X .The extension to the general process AB →V (→l ¯l ′)X is straightforward.In this case Eqs.(4),(5)and (11)can be rewritten in the formdσQ 2q e 2q1dx A dx B δ(x A x B −Q 22∞db b J 0(q T b )exp [S (b,Q )]˜f ′q/A(x A ,b 0b),(16)where σ0=4πα2/(9S )and ˜f ′q/A =f ′q/A −f ′¯q /A ,˜f ′¯q /B =f ′¯q /B −f ′q/Bare the higher order NS structure functions.Note that we have removed the non-perturbative function F NP and variable b ∗from Eq.(5),so that the above expression represents the pure perturbative result.From Eq.(16)one can easily obtain the N -th moment of the cross section with respect to τ=x A x B =Q 2/S ,Σ(N )=dττNQ 2dq 2T dQ 2=qe 2q1b)˜f ′¯q /B(N,b 0d ln µ2f ′q/H (N,µ)=γ′N f ′q/H (N,µ),(18)with the solution˜f ′q/H(N,b 0¯µ2γ′N (αS (¯µ))˜f ′q/A(N,Q ).(19)Using Eqs.(17,19)we may writeΣ(N )=G (N,Q )18The anomalous dimension γ′differs in a calculable way from thewhere G(N,Q)denotes the partonflux,G(N,Q)= q e2q˜f′q/A(N,Q)˜f′¯q/B(N,Q),(21) and the exponent U is given asU N(b,Q)=− Q2b20/b2d¯µ2¯µ2+B(¯αS(¯µ))+2γ′N(¯αS(¯µ))≡∞ n=1n+1 m=0¯αn S(Q)ln m Q2b22A(1),etc.Inserting Eq.(22)in Eq.(20)we obtainΣ(N)=G(N,Q)1b20 n D m.(23)This expression may be integrated by parts using the relationshipd2q2TG(N,Q) ∞0dx J1(x)d q2T b20 n D m ,≡G(N,Q) ∞0dx J1(x)d q2T b20 n D m .(25) Eq.(25)already has the structure of the DDT formula.In fact,setting ln x/b0=0in the integrand we recover exactly the DDT formula,i.e.the exponent has exactly the form of Eq.(22)with b0/b replaced by q T.Because of that we writeΣ(N)in the formΣ(N)=dq2Tn D m +R(q T)=db0q T,Q)]+R(q T)≡d b0q T,Q)]+R(q T) ,(26) 10where the remainder R is defined asR(q T)=G(N,Q) ∞0dx J1(x) exp ∞ n=1n+1 m=0¯αn S(Q)ln m Q2x2q2Tn D m .(27) Using9 ∞dx J1(x) 1,ln x b0,ln3x2ζ(3),... ,(28) we can evaluate R(q T)as a power series inαS.Wefind that the remainder contributes tothe NNNL tower of terms,three logarithms down from the leading terms(L=ln Q2/q2T), R(q T)=−G(N,Q) ζ(3)∞ j=2r j(1D2)j¯αj S(Q)L2j−3+O(¯αj S L2j−4) ,(29)withr2,r3,r4,r5,r6,r7,... = 8,403,4,1145,... .(30) Starting from the b-space expression we have demonstrated an extended DDT formula,dσQ2 q e2q 10dx A dx Bδ(x A x B−Q2dq2T˜f′q/A(x A,q T)˜f′¯q/B(x B,q T)exp[T(q T,Q)]+O(¯αj S L2j−3) ,(31)which holds if we drop NNNL terms.In the above expression the q T-space Sudakov form factor is given byT(q T,Q)=− Q2q2T d¯µ2¯µ2+˜B(¯αS(¯µ)) ,(32) where the q T-space coefficients˜A and˜B are defined in a similar way as their b-space counterparts,i.e.˜A(αS )=∞i=1¯αi S˜A(i),˜B(αS)=∞ i=1¯αi S˜B(i).(33)Thefirst two coefficients in˜A and˜B would be exactly the same as corresponding b-space coefficients if we drop NNNL terms.However,by making the particular choice of˜A(1)=A(1),˜A(2)=A(2),˜B(1)=B(1),˜B(2)=B(2)+2(A(1))2ζ(3),(34)we absorb thefirst term in the NNNL tower of logarithms.In this way Eq.(34)imposes exact agreement between the b-space and q T-space formalisms at orderα2S.As we pointed out at the beginning of this section,the extension of the NS cross section for AB→γ∗X to the general case of AB→V(→l¯l′)X which includes the decay presents no difficulties,so that our q T-space equivalent of Eq.(5)is given in the extended DDT form as˜Y r (q2T,Q2,y,θ)=Θ(Q2−q2T)1dq2T f′a/A(x A,q T)f′b/B(x B,q T)exp[T(q T,Q)],(35)with T given in Eq.(32)in terms of coefficients of Eqs.(33,34).The above equation is the central result of this paper.It is still ill-defined in the small q T region,which reflects the fact that the problem is not entirely determined by perturbation theory and requires non-perturbative input.We will discuss our model for the non-perturbative region later in the following section.4Results4.1Form factorsBefore presenting our results for W and Z production we compare the form factors cal-culated using the b-space and q T-space formulae,for values of Q which are presently of12interest.In practice this means Q ≤M Z .The comparison of the form factors will allow us to make an estimate of the practical numerical importance of transverse momentum conservation,i.e.of the subleading terms which are not present in the q T -space formalism.To simplify the comparison we will consider the effects of the Sudakov form factor alone.We will therefore ignore the influence of modified parton distribution functions on the q T dependence.For the purpose of illustration we take Q =M Z and αS (M Z )=0.113.We define the b -space form factor asF(b )(q T )=Q 22∞db b J 0(bq T )exp[S (b ∗,Q )]F NP (Q,b,x A ,x B ).(36)Note that F NP and b ∗have to be introduced in the above expression as a prescription for dealing with the non-perturbative region of large b .A specific choice of the non-perturbative function should make a difference only in the region of low q T .In order to show that,in Figure 2we present form factors evaluated with F NP taken from Ref.[11](LY),and with an effective gaussian as used in Ref.[13](ERV,g =3.0GeV 2).For LYform factor we take x A =x B =M Z /√S =1.8TeV.As expected,at large q T the form factors resulting from the two choices of F NP agree.For small q T we find that results for F (b )(q T )tend to a different finite intercept controlled by the non-perturbative function.The above b -space expression for the form factor should be compared to its q T -space counterpart,F (q T )(q T )=Q 2dq 2T2n =12n −1 m =0¯αnSlnmQ 21C0=˜B(1),2C3=−12˜B(1)),2C1=˜A(2)+˜B(1)(β0−˜B(1)),2C0=˜B(2).(39) As one can see from Figure3,in the region where one can trust perturbation theory (q T≥3GeV),our q T-space result of Eq.(37)agrees well with the b-space form factor (obtained with ERV non-perturbative function).Further,it is clear that resummation is needed in the region where F(b)and F(q T)differ significantly from the perturbative result.It is also interesting to investigate the size of the NNNL effects.In Figure4we show the q T-space form factor F(q T)(q T)calculated using coefficients given in Eq.(34),and also the one calculated with˜B(2)replaced by B(2).As one can see,the change is never more than a few percent for q T>3GeV.We therefore conclude that the b-space and q T-space formula are substantially identical, despite the neglect of NNNL terms in the latter.The differences between them are smaller than the differences introduced in the b-space formalism by the use of different non-perturbative functions.The above conclusion holds for the particular case of the vector boson production with Q≤M Z.4.2Extension to the non-perturbative regionAs we have already pointed out,there are two main advantages of the q T-space approach over the b-space formalism:first,outside of the non-perturbative region one can make theoretical predictions based on perturbation theory alone with soft gluon resummation effects included.In Figures5and6we show predictions of Eq.(35)for W++W−and Z production at Fermilab Tevatron.It is clear that these predictions are quite close to typical b-space results.Second,matching of the resummation formalism onto pure pertur-14bation theory for large q T is explicit,and hence there is no need for somewhat unnatural switching from one type of theoretical description to another.Since our calculation con-tains the O(αS)finite part and the O(α2S)Sudakov form factor,there still may be some residual unmatched higher order effects present in dσ/dq T in the large q T region,where the cancellation of the resummed part and subtractions from thefinite part is quite delicate. However,these effects are expected to be small,and should be even less important after the inclusion of the second order calculation of Y f.The q T-space matching is illustrated in Figure7for W++W−production at Tevatron,and should be compared to the b-space result shown in Figure1.Note that less than2%of the total cross section lies above q T=50GeV,so the overall importance of the portion of the cross section shown in Fig.7 is quite small.Up to now we have discussed only the q T-space predictions in the perturbative region, i.e.for q T≥2−3GeV.Still,in order to compare theoretical predictions to experimentone has tofind a way of dealing with the non-perturbative region(q T→0),where Eq.(35) is ill-defined.The form of˜Y r suggests that we make the following replacement in Eq.(35): f′a/A(x A,q T)f′b/B(x B,q T)exp[T(q T,Q)]−→f′a/A(x A,q T∗)f′b/B(x B,q T∗)exp[T(q T∗,Q)]˜F NP(q T).(40) Here,q T∗is the effective transverse momentum and˜F NP is the q T-space non-perturbative part of the form factor.Since the above replacement should affect only the region of small q T,we define q T∗asq2 T∗=q2T+q2Tlimexp −q2Tdq2T ˜F NP(qT)→const.(for q T→0).(42) 15The first two properties ensure that the integral of ˜Y r over q 2Tgives the resultQ 20dq 2T ˜Y r (q 2T ,Q 2,y,θ)=1dq 2T∝˜aa,b ′H (0)ab (θ)f ′a/A (x A ,q Tlim )f ′b/B (x B ,q Tlim )exp [T (q Tlim ,Q )],ddq 2T∝−˜a 2a,b′H (0)ab (θ)f ′a/A (x A ,q Tlim )f ′b/B (x B ,q Tlim )exp [T (q Tlim ,Q )].(45)Therefore,˜a and q Tlim control the intercept and the first derivative of dσ/dq 2T at q T =0.The effects of changing these non-perturbative parameters are illustrated in Figures8and 9,for W ++W −production at Fermilab Tevatron.In Figure 8we compare typical b -spaceresults for the dσ/dq 2T distribution,to the q T -space predictions with several different valuesof ˜a (q Tlim was fixed to 4.0GeV).In Figure 9we plot our dσ/dq T results obtained with ˜a fixed to 0.10GeV −2,and for several different choices of q Tlim .These results show how varying q Tlim modifies the width and shifts the peak of the dσ/dq T distribution.From Figures 8and 9it is also clear that ˜a and q Tlim affect only the low q T region,while for q T ≥10GeV we again obtain the extended DDT result of Eq.(35).Because of that,determination of these parameters from the experimental data should not be toodifficult.164.3Overall smearingIntroduction of˜a and q Tlim allowed us to extend the validity of Eq.(35)beyond the perturbative region in q T.However,this may not be enough for a good description of experimental data,and one may need additional degrees of freedom for modelling the low q T region.10This can be achieved by choosing more complicated functional forms for q T∗and˜F NP than the ones we suggested in Eqs.(41,44),or by imposing an overall smearing on the theoretical transverse momentum distributions.Here we briefly discuss the later possibility.Suppressing irrelevant variables,the smeared cross section is given in terms of˜Y i (q2T)= d2k T f(|k T−q T|)˜Y i(k2T),(46)where˜Y i stands for either resummed orfinite part in q T-space,and f is the smearing function.For the sake of simplicity we take a gaussian,f(k T)=˜g10We remind the reader that some choices of the non-perturbative function in the b-space formalism involve4-6different parameters.175ConclusionsIn this paper we have outlined an approach to the calculation of the transverse momentum distributions of W and Z bosons using an extension of the DDT formula which works directly in q T-space.Our formalism agrees with b-space for all calculated logarithms except the NNNL series.This is a pragmatic approach which uses the available theoretical in an efficient way.For q T above about3GeV the cross section is essentially determined by perturbative QCD.In the region q T≤3GeV the cross section is determined by a model,the form of which is motivated by the analytic results from the b-space approach.Just as in the b-space approach,the details of the model are to befixed by comparison with experiment.The numerical program incorporating our results describes all kinematic regions.An obvious shortcoming of this paper is the failure to include the results of the order α2S calculations[17,19,20](generalized to include the decay of the vector boson[21,22]) in thefinite part of the cross section.In the q T-space formalism these should be relatively straightforward to include.After inclusion of these effects we will have a full description of vector boson production valid in all kinematic regions,with a minimum of model dependence.ACKNOWLEDGMENTSThis work was supported in part by the U.S.Department of Energy under Contract No. DE-AC02-76CH03000.=0A Analytic behaviour at qTThe result of Parisi and Petronzio[5]for the intercept at q T=0can be obtained by saddle point evaluation of Eq.(36),Q2F(b)(0)=In writing the above equation we have assumed that the saddle point value of b is small so that b∗=b and F NP(b)=1.Introducing the variable x=ln b2we have thatF(b)(0)=Q24 h′′(x SP)exp[−h(x SP)],(52)where x SP=ln b2SPis defined by the conditionh′(x SP)=0.(53) On the assumption that the structure functions are slowly varying functions of the scale, the resummed part at q T=0becomesY r(0,Q2,y,θ)=b2SP2πb SP)f′b/B(x B,b0d(ln b2)2.(55)By retaining only the leading term(A1)in the Sudakov form factor we can obtain an approximate analytic solution.We assume that the running coupling satisfies the equation(β0=(33−2n f)/6)αS(µ)=2πlnµ2/Λ2,(56)and set C=2C F/β0.The saddle point of the integral is then given by1b0 Q C+1.(57)19Using Eqs.(54,57)we obtain thefinal result for the resummed part of the cross section (L=ln Q2/Λ2),Y r(0,Q2,y,θ)≈b202πCLQ2 η a,b′H(0)ab(θ)f′a/A(x A,b0b SP),(58)withη=C lnC+1References[1]H.Fritzsch and P.Minkowski,Phys.Lett.B73,80(1978);G.Altarelli,G.Parisi and R.Petronzio,Phys.Lett.B76,351(1978);K.Kajantie and R.Raitio,Nucl.Phys.B139,72(1978);F.Halzen and D.M.Scott,Phys.Rev.D18,3379(1978).[2]For a review see,R.K.Ellis,W.J.Stirling and B.R.Webber,QCD and ColliderPhysics,Cambridge University Press,(1996).[3]Yu.L.Dokshitzer,D.I.Dyakonov and S.I.Troyan,Phys.Rep.58,269(1980).[4]S.D.Ellis,N.Fleishon and W.J.Stirling,Phys.Rev.24,1386(1981).[5]G.Parisi and R.Petronzio,Nucl.Phys.B154,427(1979).[6]J.Collins,D.Soper and G.Sterman,Nucl.Phys.B250,199(1985).[7]G.Altarelli,R.K.Ellis,M.Greco,G.Martinelli,Nucl.Phys.B246,12(1984).[8]J.C.Collins and D.Soper,Nucl.Phys.B193,381(1981);Erratum Nucl.Phys.B213,545(1983);Nucl.Phys.B197,446(1982).[9]C.Davies,B.R.Webber and W.J.Stirling,Nucl.Phys.B256,413(1985).[10]P.B.Arnold and R.P.Kauffman,Nucl.Phys.B349,381(1991).[11]dinsky and C.-P.Yuan,Phys.Rev.D50,4239(1994).[12]C.Bal´a zs,J.Qiu,and C.–P.Yuan,Phys.Lett.B355,548(1995).[13]R.K.Ellis,D.A.Ross and S.Veseli,Fermilab preprint FERMILAB-PUB-97/082-T,hep-ph/9704239(Nucl.Phys.B,in press).[14]C.Bal´a zs and C.–P.Yuan,MSUHEP–70402,hep-ph/9704258.21[15]J.Collins and D.Soper,Phys.Rev.D16,2219(1977).[16]C.Davies and W.J.Stirling,Nucl.Phys.B244,337(1984);C.T.H.Davies,University of Cambridge Ph.D.thesis,(1984).[17]R.K.Ellis,G.Martinelli and R.Petronzio,Nucl.Phys.B211,106(1983).[18]A.D.Martin,R.G.Roberts and W.J.Stirling,Phys.Lett.B387,419(1996).[19]P.Arnold and M.H.Reno,Nucl.Phys.B319,37(1989),Erratum Nucl.Phys.B330,284(1990);P.Arnold,R.K.Ellis and M.H.Reno,Phys.Rev.D40,912(1989).[20]R.Gonsalves,J,Pawlowski and C-F Wai,Phys.Rev.D40,2245(1989).[21]E.Mirkes,Nucl.Phys.B387,3(1992);E.Mirkes and J.Ohnemus,Phys.Rev.D51,4891(1995).[22]W.Giele,E.Glover,D.A.Kosower,Nucl.Phys.B403,633(1993),Phys.Lett.B309,205(1993).[23]F.Abe et al.,Phys.Rev.Lett.66,2951(1991).[24]F.Abe et al.,Phys.Rev.Lett.67,2937(1991).22Figure1:Comparison of the b-space dσ/dq T distribution for W++W−production at√24Figure3:Form factors F(b),F(q T)and F(p).The b-space results were obtained with an effective gaussian form of F NP(g=3.0GeV2,b lim=0.5GeV−1).25Figure4:The q T-space form factor F(q T)calculated with B(2)and˜B(2).26Figure5:Comparison of various theoretical predictions for W++W−dσ/dq T with CDF data[23].The b-space results were obtained with an effective gaussian form of F NP (g=3.0GeV2,b lim=0.5GeV−1).We assumed BR(W→eν)=0.111.27Figure6:Comparison of various theoretical predictions for Z dσ/dq T with CDF data [24].The b-space results were obtained with an effective gaussian form of F NP(g= 3.0GeV2,b lim=0.5GeV−1).We assumed BR(Z→e+e−)=0.033.28Figure7:Comparison of the q T-space dσ/dq T distribution for W++W−production at √Figure8:Various theoretical predictions for dσ/dq2T in W++W−production at√Figure9:Various theoretical predictions for dσ/dq T in W++W−production at √√Figure10:Effects of smearing in q T-space for W++W−production at。
