Traffic congestion and congestion pricing
C. Robin Lindsey and Erik T. V erhoef
Department of Economics University of Alberta Department of Spatial EconomicsFree University Amsterdam
Abstract
For several decades growth of traffic volumes has outstripped investments in road infrastructure. The result has been a relentless increase in traffic congestion. This paperreviews the economic principles behind congestion pricing in static and dynamic settings,which derive from the benefits of charging travellers for the externalities they create. Specialattention is paid to various complications that make simple textbook congestion pricingmodels of limited relevance, and dictate that congestion pricing schemes be studied from theperspective of the theory of the second best. These complications include pricing in networks,heterogeneity of users, stochastic congestion, interactions of the transport sector with the restof the economy, and tolling on private roads. Also the implications of congestion pricing foroptimal road capacity are considered, and finally some explanations for the longstanding social and political resistance to road pricing are offered.
Key words: congestion, road pricing, networks
JEL codes: R41, R48, D62
1. Introduction
For several decades growth of traffic volumes has outstripped investments in road infrastructure. The result has been a relentless increase in traffic congestion. Congestion imposes various costs on travellers: reduced speeds and increased travel times, a decrease in travel time reliability, greater fuel consumption and vehicle wear, inconvenience from rescheduling trips or using alternative travel modes, and (in the longer run) the costs of relocating residences and jobs. The costs of increased travel times and fuel consumption alone are estimated to amount to hundreds of dollars per capita per year in the US (Schrank and Lomax, 1999) and comparable values have been reported for Europe.
Traffic congestion is a consequence of the nature of supply and demand: capacity is time- consuming and costly to build and is fixed for long time periods, demand fluctuates over time,and transport services cannot be stored to smooth imbalances between capacity and demand.V arious policies to curb traffic congestion have been adopted or proposed over the years. The traditional response is to expand capacity by building new roads or upgrading existing ones. A second method is to reduce demand by discouraging peak-period travel, limiting access tocongested areas by using permit systems and parking restrictions, imposing bans on commercial vehicles during certain hours, and so on. A third approach is to improve the efficiency of the road system, so that the same demand can be accommodated at a lower cost.Re-timing of traffic lights, metering access to highway entrance ramps, high-occupancy vehicle lanes and Advanced Traveller Information Systems are examples of such measures.
This paper is concerned with congestion pricing as a tool for alleviating traffic congestion. The insight for congestion pricing comes from the observation that people tend to make socially efficient choices when they are faced with all the social benefits and costs of their actions. As just noted various demand management tools to accomplish this can be used.But congestion pricing is widely viewed by economists as the most efficient means because it employs the price mechanism, with all its advantages of clarity, universality, and efficiency. Pigou (1920) and Knight (1924) were the first to advocate it. But it was the late William Vickrey, who steadfastly promoted congestion pricing for some forty years, who was arguably the most influential in making the case on both theoretical and practical grounds. In one of his early advocacy pieces, Vickrey (1963) identified the potential for road pricing to influence travellers? choice of route and travel mode, and its implications for land use. He also discussed alternative methods of automated toll collection. Another of his early proposals was to set parking fees in real time as a function of the occupancy rate. An overview of Vickrey?s contributions to pricing of urban private and public transport is found in Arnott et al. (1994,pp. 271-5).
As Vickrey?s work makes clear, true congestion pricing entails setting tolls that match the severity of congestion, which requires that tolls vary according to time, location, type of vehicle and current circumstances (e.g. accidents or bad weather). Congestion pricing is common in other sectors of the economy —from telephone rates and air fares to hotels and public utilities. But despite the efforts of Vickrey and other economists, congestion pricing is still rarely used on roads. Tolls are not charged on most roads, and fuel taxes do not vary with traffic volumes. And costs of registration, licensing and insurance do not even depend on distance travelled. Nevertheless, the number of applications and experiments in road pricing is slowly growing, spurred on by the combined impetus of worsening traffic conditions and advances in automatic vehicle identification technology. Descriptions of various road pricing schemes, including Singapore?s pioneering toll system, Scandinavian toll-rings, and Californian pay-lanes are found in Gómez-Ibá?ez and Small (1994) and Small and Gómez Ibá?ez (1998).
This paper is organized along similar lines to the review of congestion modelling in Lindsey and V erhoef (2000). Section 2 starts by outlining the basic economic principles of congestion pricing in a simple static (…time-independent?) setting with one road. Section 3 adds a t ime element by considering travellers? time-of-use decisions and time-varying tolls. V arious complications are addressed in Section 4, including pricing in networks,heterogeneity of users, stochastic congestion, interactions of the transport sector with the rest of the economy, and tolling on private roads. Section 5 considers the implications of congestion pricing for optimal road capacity. Explanations for the longstanding social and political resistance to road pricing are offered in Section 6, and conclusions are drawn in Section 7. Due to space constraints some topics related to congestion pricing are not covered in this review. There is no explicit treatment of freight transportation. Nothing is said about the implications of congestion pricing for urban structure or the location of new developments. And only passing mention in Section 4 is given to the potential effects
of congestion pricing on traffic noise, pollution, and traffic accidents.
2. Congestion pricing in time-independent models
The basic principles of congestion pricing can be illustrated in the following simple setting.Consider one origin and one destination connected by a single road. Individuals make trips alone in identical vehicles. Traffic flows, speeds and densities are uniform along the road and independent of time. Equilibrium in this setting is described in Figure 1, which is due to Walters (1961). The horizontal axis depicts traffic flow or volume: the rate at which trips are initiated and completed. The vertical axis depicts the price or …generalized cost? of a trip —which includes vehicle operating costs, the time costs of travel, and any toll. At low volumes vehicles can travel at the free-flow speed, and the trip cost curve, C(q), is constant at the free-flow cost Cff At higher volumes congestion develops, speed falls, and C(q) slopes upwards. The fact that a toll is required to support the social optimum reveals the fallacy that travellers fully pay for the congestion they cause through the time they personally lose.Analogously, a person squeezing through a crowd, a shopper queuing in line at a supermarket counter, or a person reading a popular library book after a long wait for it, impose costs on others that they do not themselves bear.
3. Congestion pricing in time-dependent models
Time-dependent models of congestion build on time-independent models by adding two elements: a specification of how travel demand depends on time, and a specification of how traffic flows evolve over time and space. To maintain focus on the time elements of congestion pricing, attention will be limited as in Section 2 to a single road joining one origin and one destination. Until near the end of Section 3 it will also be assumed that the total number of trips is fixed; i.e. price inelastic. But heterogeneity in the trip-timing preferences and time costs of travellers is allowed.
Several policy lessons can now be drawn. First, congestion pricing not only reduces travel times but also affects schedule delay costs. A cost-benefit analysis that considered only travel times could be biased either for or against a congestion pricing project, and might lead either to unwarranted acceptance or rejection of it. Second, the efficiency gains from congestion pricing are of the same order of magnitude as toll revenue, and can even exceed it. By contrast, the efficiency gains from flat tolls computed using static models can be dwarfed by the toll transfers involved. This suggests that the economics of dynamic congestion pricing schemes are not as sensitive to the costs of infrastructure and operation as are the economics of tolling schemes in static models. Third, congestion pricing has welfare distributional effects on travellers that tend to favour those with high values of time. Because value of time is positively correlated with income, this is consistent with the conventional view that tolling is regressive. Finally, under the fine toll all individuals pay the full marginal social costs of their trips, regardless of their respective characteristics and of when they travel.
4. Second-best issues in congestion pricing
Sections 2 and 3 have outlined the principles of congestion pricing when tolls can be set to match the external costs generated by each traveller. Such pricing is called …first-best?congestion pri cing because it supports a first-best optimum in which roads
are used at maximum efficiency. Although useful as a theoretical benchmark, first-best pricing is increasingly recognized as of limited practical relevance. Attention has turned in the recent lit erature to more realistic types of …second-best? congestion pricing, in which various costs or constraints deter or prevent the setting of first-best tolls. Examples of second-best tolling include the use of toll-cordons around cities instead of tolling each road in the network, the use of step-tolls instead of smoothly time-varying tolls, tolling according to a fixed daily schedule rather than day-specific traffic conditions, etc. The rules for setting optimal second-best tolls are generally quite complicated because they must reflect all sorts of indirect effects,both good and bad.
Evidence that congestion pricing may well produce adverse network effects is suggested by a recent study by May and Milne (2000). Using steady-state equilibrium simulations on a road network in Cambridge, UK, they compare congestion pricing with three other road pricing schemes: cordon pricing, time-based pricing, and distance-based pricing. The tolls considered were not second-best optimal tolls as described above, but various exogenously determined toll levels instead. All four schemes were found to be prone to adverse boundaryeffects, including “rat running” (where road users seek untolled routes). More discouragingly,a smaller percentage of travellers enjoyed travel time reductions with congestion pricing than with the other schemes. By inducing travellers to re-route to less congested roads, congestion pricing also had a tendency to increase travel distances —with potentially adverse environmental effects. These findings suggest that route-choice decisions deserve particular scrutiny in the design and evaluation of real-world congestion pricing projects. De Borger & Proost (2000) report on the relative efficiency of km-charges, fuel charges, parking charges and public transport pricing for different cities and countries, using the multi-modal TRENEN-model. They find that parking charges combined with cordons can achieve efficiencies of more than 70% of the first-best ideal in some cases, while the potential of fuel pricing and public transport pricing is rather limited.
One consideration not addressed in these studies is the attitude of drivers toward tolling under uncertainty. It is unclear as yet from the limited formal research whether drivers are better off in terms of expected travel costs under nonresponsive or responsive pricing. Some surveys have found that drivers dislike uncertainty about how much they will have to pay in tolls. Aversion to uncertainty about payment was one of the reasons for opposition to the congestion metering project planned for Cambridge, England, in which vehicles would have been charged on the basis of actual congestion experienced. However, drivers have been receptive to the recent adoption of responsive pricing on Interstate I-15 north of San Diego. Further research is clearly called for on the economics and politics of road pricing under uncertainty.
5. The social and political feasibility of congestion pricing
Despite its economic appeal, road congestion pricing appears to enjoy little support outside academia. The limited social and, consequently, political support for congestion pricing has caused many proposed schemes to be abandoned before
implementation, or at least to be postponed (sometimes indefinitely). These include detailed plans for Hong Kong, London, The Randstad, and Stockholm (Small and Gómez-Ibá?ez, 1998).
One important reason for opposition to congestion pricing was identified in Section 2:before redistribution of toll revenues, everybody except the taxman appears to be worse off.This results should be qualified on two counts. First, if congestion takes the form of pure queuing and users have identical values of time, a fine toll leaves users equally well off Second, users with a high value of travel time may benefit from congestion pricing even before revenue recycling; see Section 3, Richardson (1974), and supporting empirical evidence from a Dutch survey by V erhoef et al. (1997a). Still, because value of time is positively correlated with income, this implies that road pricing is regressive —which is unlikely to improve the social acceptability of congestion pricing.
According to economists, congestion pricing is the best instrument for controlling congestion. Y et the bulk of empirical evidence suggests that, even with cleverly designed tolling mechanisms and toll revenue allocation schemes, congestion pricing is likely to remain difficult to implement. It is no coincidence that the only area-wide congestion pricing scheme currently in operation is in Singapore, where the culture allows the government to implement unpopular policies. Indeed, Frick et al. (1996) infer from the series of failed attempts to implement congestion pricing on the San Francisco Bay Bridge that both the public and officials must be convinced that no feasible alternative to congestion pricing exists before it will be accepted.
6. Conclusion
Given forecasts of continuing growth in road travel, and the reduced scope for expansion of road infrastructure, traffic congestion is not a problem that will go away soon. Recent advances in electronic vehicle identification and automated charging technologies have made congestion pricing a viable means of combating traffic congestion, rather than just an academic curiosum. This paper reviews the economic principles behind congestion pricing,which derive from the benefits of charging travellers for the externalities they create.Attention is paid to various complications that make simple textbook congestion pricing models of limited relevance, and dictate that congestion pricing schemes be studied from the perspective of the theory of the second best.
Despite the economic case for congestion pricing, it has attracted strong social and political opposition, and assorted legal and institutional constraints create further barriers to implementation. It thus seems safe to conclude with the prediction that coming decades will witness an increasing number of attempts to implement congestion pricing, many of which will fail in their early stages, but some of which will succeed if only on a piecemeal basis. The design and evaluation of such schemes will probably require a deeper understanding of the direct and indirect impacts of congestion pricing than is available to date. One can hope, therefore, that this review will be obsolete before too long.
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篇一：高中语文说课模板通稿 各位评委老师：大家好，我是几号考生，我今天说课的题目是《》。下面，我将会从说教材、说教法、说学法、说教学过程等部分来进行我的说课。 一、说教材 教材简析：本篇课文是人教版高中语文课本必修几第几册第几单元第几课的课文，是一篇什么体裁的文章。文章主要叙述的容是什么，表现了作者什么样的思想感情。本篇课文具有什么样的地位，和什么特色。学习教材的目的是为了让学生能够触类旁通，举一反三，能将知识由课向课外延伸。通过对本篇课文学习，能够更好的培养学生的鉴赏能力和归纳总结能力。 教学目标： （一）诗歌：根据教学大纲的要求，诗歌教学要以诵读为主，在诵读中使学生领悟诗的思想感情，鉴赏文学作品能够感受形象，品味语言。同时，本篇诗歌通过典型意象创造出优美的意境，巧妙的将诗人的情感融入其中。确立教学目标如下： 我的知识目标是：品味诗的意象美，领悟诗的意境，体会诗人的真情。 能力目标是：培养学生鉴赏诗歌的能力。 德育目标是：体悟作者情怀，引发共鸣，逐渐养成良好的审美情趣，培养审美能力。 本节课的教学重点是：领反复诵读，鉴赏诗歌意象，体会诗歌的意境美，体悟诗情，获得情感体验。教学难点是：把握诗歌的思想感情，以及意象的体味与把握。 （二）文言文：根据教学大纲的要求，文言文教学要求培养学生阅读浅显文言文的能力，把握文章的思想容，积累语言知识。同时本课情节、结构、语言等的特点，确立教学目标如下： 知识与能力目标：了解作者的基本常识；理解文中所出现的生僻词以及意义特殊的词语；把握文中的主要思想感情，初步鉴赏文中的形象与个性。 过程与方法：通过诵读质疑、自主探究、合作解决，培养学生借助注释和工具书阅读浅显文言文，理解重点词句的含义以及初步的研究分析能力并积累文言文实词、虚词和句式，培养学生的自学能力和翻译能力。情感态度与价值观目标：理解作者在作品中所流露出的情感，培养正确的审美观/价值观/人生观。 我确定以上的三个目标是体现新课标所提倡的“知识与能力、过程与方法、情感与态度”并重的教学理念。教学重点：诵读课文，在把握文意的基础上理解词句，积累一些文言实词、虚词和句式。 教学难点：掌握文章的写作风格和特点；深入分析文章涵，并作出评价，激发学生的学习兴趣。 （三）现代文：新课标强调了要全面提升高中学生的语文素养，初步形成正确的人生观、世界观、价值观，并学会收集判断、处理信息，具有人文素养、创新精神与实践能力。同时本篇课文，感情真挚，感悟深刻，具有典型的人文性，结合本单元的教学目标以及本篇课文在语言，结构设置等方面的特点，确立本课的教学目标如下： 知识能力目标：领悟本文的写作手法，揣摩语言，体会语言的感情和特色，学习作者运用语言的技巧。同时学习本文对比喻、拟人等修辞手法的运用。 过程与方法目标：在教师恰当的提升引导下，培养学生“自主、合作、探究”的学习方式，并掌握一定的赏析语言的能力与方法。 情感与态度目标：理解作者在作品中所流露出的情感，培养正确的审美观/价值观/人生观。 我确定以上的三个目标是体现新课标所提倡的“知识与能力、过程与方法、情感与态度”并重的教学理念。我的教学重点是：理清本篇文章的思路，领会课文的思想感情。教学难点
防火墙操作手册 ----USG6550(V100R001)
1.安装前的准备工作 在安装USG前，请充分了解需要注意的事项和遵循的要求，并准备好安装过程中所需要的工具。 安装注意事项 在安装USG时，不当的操作可能会引起人身伤害或导致USG损坏，请在安装USG前详细阅读本安全注意事项。 检查安装环境 安装USG前，请检查安装环境是否符合要求，以保证USG正常工作并延长使用寿命。 安装工具准备 安装USG过程中需要使用到如下工具，请提前准备好。 2.安装注意事项 1)所有安全注意事项 为保障人身和设备安全，在安装、操作和维护设备时，请遵循设备上标识及手册中说明的所有安全注意事项。 手册中的“注意”、“小心”、“警告”和“危险”事项，并不代表所应遵守的所有安全事项，只作为所有安全注意事项的补充。 2)当地法规和规范
操作设备时，应遵守当地法规和规范。手册中的安全注意事项仅作为当地安全规范的补充。 3)基本安装要求 负责安装维护华为设备的人员，必须先经严格培训，了解各种安全注意事项，掌握正确的操作方法之后，方可安装、操作和维护设备。 只允许有资格和培训过的人员安装、操作和维护设备。 只允许有资格的专业人员拆除安全设施和检修设备。 替换和变更设备或部件（包括软件）必须由华为认证或授权的人员完成。 操作人员应及时向负责人汇报可能导致安全问题的故障或错误。 4)人身安全 禁止在雷雨天气下操作设备和电缆。 为避免电击危险，禁止将安全特低电压（SELV）电路端子连接到通讯网络电压（TNV）电路端子上。 禁止裸眼直视光纤出口，以防止激光束灼伤眼睛。 操作设备前，应穿防静电工作服，佩戴防静电手套和手腕，并去除首饰和手表等易导电物体，以免被电击或灼伤。 如果发生火灾，应撤离建筑物或设备区域并按下火警警铃，或者拨打火警电话。任何情况下，严禁再次进入燃烧的建筑物。
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（REP01T01 V2.31/ IPD-CMM V2.0 / for internal use only）（REP01T01 V2.31/ IPD-CMM V2.0 / 仅供内部使用） Revision record 修订记录 Date 日期 Revision V ersion 修订 版本 CR ID / Defect ID CR号 Section Number 修改 章节 Change Description 修改描述 Author 作者 2003-09-10 1.00 initial 初稿完成 赵强 Distribution List 分发记录 Copy No. Holder's Name & Role 持有者和角色 Issue Date 分发日期 1 yyyy-mm-dd
Catalog 目录 1 Introduction 简介 (7) 1.1 目的 (7) 1.2 范围 (7) 1.3 发布对象 (7) 2 Eudemon200防火墙的特点 (8) 2.1 基于状态的防火墙 (8) 2.2 安全域概念介绍 (8) 2.2.1 防火墙的域 (8) 2.2.2 域间概念 (10) 2.2.3 本地域（Local） (10) 2.3 防火墙的模式 (11) 2.3.1 概述 (11) 2.3.2 路由模式 (11) 2.3.3
目录 1、《荷塘月色》说课稿 (3) 2、《故都的秋》说课稿1 (6) 2、《故都的秋》说课稿2 (8) 3、《囚绿记》说课稿 (11) 4、诗经两首《氓》说课稿 (12) 5、《离骚》说课稿 (15) 6、孔雀东南飞说课稿 (17) 7《涉江采芙蓉》说课稿一． (18) 7、短歌行说课稿 (19) 8、归园田居其一说课稿 (20) 9、兰亭集序》说课 (23) 10、赤壁赋说课稿 (24) 11、《游褒禅山记》说课稿（2则） (26) 12、就任北京大学校长之演说 (30) 13、我有一个梦想说课稿 (35) 14、《在马克思墓前的讲话》说课稿 (38) 15、林黛玉进贾府说课稿 (39) 16、《祝福》说课稿 (43) 17、《老人与海》说课稿 (45) 18蜀道难说课稿 (46) 19、《秋兴八首》（其一）教案 (48) 20、杜甫诗三首》说课稿 (49) 21、琵琶行说课稿 (51) 22、李商隐诗2首 (53) 23、《寡人之于国也》说课稿 (55) 24、《劝学》说课稿 (58) 24《劝学》创新课说课稿 (59) 25、过秦论说课稿 (61) 26、师说》说课稿 (63) 27、动物游戏之谜 (65) 27-1动物游戏之谜 (67) 28、《宇宙的边疆》 (69) 13-1、宇宙的边疆 (70) 29、一名物理学家的教育历程》说课稿 (71) 30、《窦娥冤》说课稿 (75) 30-1、《窦娥冤》说课稿 (76) 30-2《窦娥冤》说课稿 (77) 31、《雷雨》说课稿 (79) 32、《哈姆雷特》说课稿 (81) 33、《望海潮》说课稿 (82) 34、《雨霖铃》说课稿 (83) 35、《苏轼词两首》说课稿 (84) 36、《念奴娇赤壁怀古》说课稿 (86) 37、《水龙吟》教案 (89)
《永远的校园》 教学目的: 1.了解北大，走近北大，感受北大，思考北大 2. 借助演讲、辩论等形式培养学生思辨说理的能力 3.对比谢冕心中的北大与现实中北大的差异，并揣摩这种差异的根源，从而树立正确的大学观、人生观 教学难点： 如何看待理想中北大与现实中北大的差异 教法与学法： 1．课型：讲读课、公开课、研讨课、活动课 2．教法：质疑、讨论、辩论 3．教具及能力培养方向：多媒体课件（包括图片、音频、视频及文字材料）；培养学生思辨能力 课时安排：2课时（第一课时主要诵读文章，感知大意；第二课时主要展开拓展、延伸的活动） 教学过程： 一、新课导入 2003年2月25日，在首都北京发生了二起震惊中外的爆炸案，先后发生在清华大学的荷园餐厅和北京大学的农园餐厅，虽然比不上恐怖份子驾机撞毁世贸大楼那样引人注目，但在很少发生恐怖流血冲突的中国大陆来说，这的确也算得上是惊天动地的事情了，最引人深
思的是：恐怖份子为什么要选择清华和北大进行作案呢？案情侦破之后，答案浮出水面，而这个答案竟让人哭笑不得，因为犯罪谷子声称：“制造爆炸案的目的是为了出名。” 对于这起事件，我不想多作分析了，我只是想说：为什么炸清华、北大就能出名呢？那是因为这两所大学太有名了，本身就是名望的象征。我们这就容易理解了：为什么从古至今那些杀人的罪犯很少留下姓名，而刺客荆轲的故事却被广为传诵，不仅仅是因为荆轲的大义凛然、高风亮节，还因为他刺杀的对象是权倾天下、赫赫有名的秦王。 的确，清华、北大太有名气了，不仅是每一位莘莘学子梦寐以求的地方，就连没有丁点儿文化常识的人可能也会对他们肃然起敬。江泽民同志作为一国主席，日理万机，我不知道他曾去过哪些大学，但我知道北大他是去过的，就在北大建校一百周年的校庆典礼上，还作了热情扬溢的讲话，因此，才有了我们课本上这篇文章。 大凡有名望的人、事、物都难得一见：比如卢浮宫珍藏的那些传世珍品；比如我们的局长、县长、市长或者更高的官员。于是我们容易对那些有名望的东西产生神秘感，认为他们与众不同，认为他们超凡脱俗，认为他们高不可攀，或许真的如此，或许未必竟然。那么，今天，我们就一起走进北大著名学者、中国当代著名诗歌理论家、朦胧诗派的倡导者谢冕先生用他的眼、他的手、他的心为我们搭建的北大校园，去感受北大的那一份脱俗和平凡吧！ 二、感受北大
高中语文新课程标准教材 语文教案( 2019 — 2020学年度第二学期 ) 学校： 年级： 任课教师： 说课稿 / 高中说课稿 / 高中说课稿范文 编订：XX文讯教育机构
高中语文《鸿门宴》说课稿模板 教材简介:本教材主要用途为通过学习语文的内容，培养学生的阅读能力、交流能力，学习语文是为了更好的学习和工作，为了满足人类发展和实现自我价值的需要，本说课稿资料适用于高中语文科目, 学习后学生能得到全面的发展和提高。本内容是按照教材的内容进行的编写，可以放心修改调整或直接进行教学使用。 各位评委，各位同仁： 大家好!今天我说课的题目是《鸿门宴》。下面我将从：教材、教法、学法、课时安排、教学过程五个方面来进行我的说课。 一、说教材 1、教材简析及该课所处的地位作用： 《鸿门宴》是人教版新教材高一年级《语文》必修1第二单元 第6课，节选自《史记》。所选情节描写的是刘邦、项羽在推翻秦王朝后，为争夺天下而进行的一场惊心动魄的政治斗争。鸿门宴是项羽在新丰鸿门设下的一个富有杀机的宴会，是刘、项之间政治矛盾由潜滋暗长到公开化的表现，是长达五年的楚汉相争的序幕，名为宴会，实则是一场激烈的政治斗争。作者以娴熟的艺术技巧，生动地刻画了不同性格的人物形象，描绘了众多富有戏剧性的令人难忘的场面，情节波澜起伏，扣人心弦。鸿门宴一文充分展示了刘、项之间不可调和的矛盾，并预示了胜负的必然结局。因此具有很高的史学价值和
文学价值。如何通过本课激起学生学习的兴趣，树立学生学好文言文的信心和领悟我国传统文化的精髓，这是一个关键所在。 2、教学目标： 高中语文教学大纲对文言文学习的要求是：诵读古典诗词和浅易文言文，背诵一定数量的名篇。掌握文中常见的文言实词、虚词和句式，能理解词句含义，读懂课文，学习用现代观念审视作品的内容和思想倾向。 根据课文特点，结合大纲要求，我确立了如下教学目标：(课件展示) 板书一二三 (1)知识和能力目标：一个巨匠，一部巨著：了解作家作品及相关史实，积累文言词句知识，学习创造性阅读。 (2)过程和方法目标：两个英雄，两种性格：利用人物个性化语言，分析人物性格，学习作者运用对照的方法和在矛盾斗争中描写人物的方法，学习一分为二地评论历史人物，树立正确的读史观。 (3)情感和价值目标：三种认知态度： ①学以致用的态度，感受司马迁隐忍发愤的著书精神，从容应对学习生活中的各种困难和挫折 ②领悟态度：分析项羽悲剧的原因，到底“败”在哪里?领悟良好的性格决定一生的命运
华为防火墙配置用户手册 防火墙默认的管理接口为g0/0/0，默认的ip地址为192.168.0.1/24，默认g0/0/0接口开启了dhcp server，默认用户名为admin，默认密码为Admin@123 一、配置案例 1.1 拓扑图 GE 0/0/1：10.10.10.1/24 GE 0/0/2：220.10.10.16/24 GE 0/0/3：10.10.11.1/24 WWW服务器：10.10.11.2/24（DMZ区域） FTP服务器：10.10.11.3/24（DMZ区域） 1.2 Telnet配置 配置VTY 的优先级为3，基于密码验证。 # 进入系统视图。
[USG5300-ui-vty0-4] authentication-mode password # 配置验证密码为lantian [USG5300-ui-vty0-4]set authentication password simple lantian ###最新版本的命令是authentication-mode password cipher huawei@123 配置空闲断开连接时间 # 设置超时为30分钟 [USG5300-ui-vty0-4] idle-timeout 30 [USG5300] firewall packet-filter default permit interzone untrust local direction inbound //不加这个从公网不能telnet防火墙。 基于用户名和密码验证 user-interface vty 0 4 authentication-mode aaa aaa local-user admin password cipher ]MQ;4\]B+4Z,YWX*NZ55OA!! local-user admin service-type telnet local-user admin level 3 firewall packet-filter default permit interzone untrust local direction inbound 如果不开放trust域到local域的缺省包过滤，那么从内网也不能telnet的防火墙，但是默认情况下已经开放了trust域到local域的缺省包过滤。 1.3 地址配置 内网： 进入GigabitEthernet 0/0/1视图 [USG5300] interface GigabitEthernet 0/0/1 配置GigabitEthernet 0/0/1的IP地址 [USG5300-GigabitEthernet0/0/1] ip address 10.10.10.1 255.255.255.0 配置GigabitEthernet 0/0/1加入Trust区域 [USG5300] firewall zone trust [USG5300-zone-untrust] add interface GigabitEthernet 0/0/1 [USG5300-zone-untrust] quit 外网： 进入GigabitEthernet 0/0/2视图 [USG5300] interface GigabitEthernet 0/0/2 配置GigabitEthernet 0/0/2的IP地址 [USG5300-GigabitEthernet0/0/2] ip address 220.10.10.16 255.255.255.0 配置GigabitEthernet 0/0/2加入Untrust区域 [USG5300] firewall zone untrust [USG5300-zone-untrust] add interface GigabitEthernet 0/0/2 [USG5300-zone-untrust] quit
高中语文说课稿范文 篇一：高中语文说课稿范文(共7篇) 篇一：高中语文说课模板通稿 各位评委老师：大家好，我是几号考生，我今天说课的题目是。下面，我将会从说教材、说教法、说学法、说教学过程等部分来进行我的说课。 一、说教材 教材简析：本篇课文是人教版高中语文课本必修几第几册第几单元第几课的课文，是一篇什么体裁的文章。文章主要叙述的内容是什么，表现了作者什么样的思想感情。本篇课文具有什么样的地位，和什么特色。学习教材的目的是为了让学生能够触类旁通，举一反三，能将知识由课内向课外延伸。通过对本篇课文学习，能够更好的培养学生的鉴赏能力和归纳总结能力。 教学目标： （一）诗歌：根据教学大纲的要求，诗歌教学要以诵读为主，在诵读中使学生领悟诗的思想感情，鉴赏文学作品能够感受形象，品味语言。同时，本篇诗歌通过典型意象创造出优美的意境，巧妙的将诗人的情感融入其中。确立教学目标如下：我的知识目标是：品味诗的意象美，领悟诗的意境，体会诗人的真情。 能力目标是：培养学生鉴赏诗歌的能力。
德育目标是：体悟作者情怀，引发共鸣，逐渐养成良好的审美情趣，培养审美能力。本节课的教学重点是：领反复诵读，鉴赏诗歌意象，体会诗歌的意境美，体悟诗情，获得情感体验。教学难点是：把握诗歌的思想感情，以及意象的体味与把握。 （二）文言文：根据教学大纲的要求，文言文教学要求培养学生阅读浅显文言文的能力，把握文章的思想内容，积累语言知识。同时本课情节、结构、语言等的特点，确立教学目标如下：知识与能力目标：了解作者的基本常识；理解文中所出现的生僻词以及意义特殊的词语；把握文中的主要思想感情，初步鉴赏文中的形象与个性。 过程与方法：通过诵读质疑、自主探究、合作解决，培养学生借助注释和工具书阅读浅显文言文，理解重点词句的含义以及初步的研究分析能力并积累文言文实词、虚词和句式，培养学生的自学能力和翻译能力。情感态度与价值观目标：理解作者在作品中所流露出的情感，培养正确的审美观/价值观/人生观。 我确定以上的三个目标是体现新课标所提倡的“知识与能力、过程与方法、情感与态度”并重的教学理念。教学重点：诵读课文，在把握文意的基础上理解词句，积累一些文言实词、虚词和句式。 教学难点：掌握文章的写作风格和特点；深入分析文章内涵，并作出评价，激发学生的学习兴趣。
华为路由器和防火墙配置命令总结 一、access-list 用于创建访问规则。 （1）创建标准访问列表 access-list [ normal | special ] listnumber1 { permit | deny } source-addr [ source-mask ] （2）创建扩展访问列表 access-list [ normal | special ] listnumber2 { permit | deny } protocol source-addr source-mask [ operator port1 [ port2 ] ] dest-addr dest-mask [ operator port1 [ port2 ] | icmp-type [ icmp-code ] ] [ log ] （3）删除访问列表 no access-list { normal | special } { all | listnumber [ subitem ] } 【参数说明】 normal 指定规则加入普通时间段。 special 指定规则加入特殊时间段。 listnumber1 是1到99之间的一个数值，表示规则是标准访问列表规则。 listnumber2 是100到199之间的一个数值，表示规则是扩展访问列表规则。 permit 表明允许满足条件的报文通过。 deny 表明禁止满足条件的报文通过。 protocol 为协议类型，支持ICMP、TCP、UDP等，其它的协议也支持，此时没有端口比较的概念；为IP时有特殊含义，代表所有的IP协议。 source-addr 为源地址。 source-mask 为源地址通配位，在标准访问列表中是可选项，不输入则代表通配位为0.0.0.0。 dest-addr 为目的地址。 dest-mask 为目的地址通配位。 operator[可选] 端口操作符，在协议类型为TCP或UDP时支持端口比较，支持的比较操作有：等于（eq）、大于（gt）、小于（lt）、不等于（neq）或介于（range）；如果操作符为range，则后面需要跟两个端口。 port1 在协议类型为TCP或UDP时出现，可以为关键字所设定的预设值（如telnet）或0~65535之间的一个数值。 port2 在协议类型为TCP或UDP且操作类型为range时出现；可以为关键字所设定的预设值（如telnet）或0~65535之间的一个数值。 icmp-type[可选] 在协议为ICMP时出现，代表ICMP报文类型；可以是关键字所设定的预设值（如echo-reply）或者是0~255之间的一个数值。 icmp-code在协议为ICMP且没有选择所设定的预设值时出现；代表ICMP码，是0~255之间的一个数值。 log [可选] 表示如果报文符合条件，需要做日志。
篇一：高中语文省级说课一等奖《李清照词两首》说课稿 《李清照词两首》说课稿 嘉峪关市一中张红丽 尊敬的各位评委、各位老师： 大家下午好！ 我今天说课的题目是《李清照词两首》，这是高一第二学期后半学期的学习内容。下面我将从教材分析、学情介绍、教学目标、教学过程四个部分来进行说明。 第一部分——教材分析 《李清照词两首》是人教版必修四第二单元中的篇目，这一单元选编的是宋词，在新课标实验教材五个必修模块中，这是唯一的宋词单元。本单元选取的是柳永、苏轼、辛弃疾、李清照四位词人的作品，四者基本完整地体现了宋词的发展脉络和艺术价值。李清照的词《醉花阴》《声声慢》放在最后，属略读篇目，安排一课时完成教学。《醉花阴》是作者南渡前的作品，抒发“相思闲愁”，《声声慢》是作者南渡后的名篇之一，将重点赏析，写词人历遭国破家亡夫丧劫难后的愁苦悲戚，是词人晚年生活的真实写照，也是时代苦难的象征。本课的学习将引导学生深入熟悉诗词鉴赏的基本方法，为以后进行诗歌与散文系列的选修打下坚实的基础。 第二部分——学情介绍 通过本单元前面六首词的学习，学生对豪放派和婉约派的风格特点已有了大体认识，对词的文体常识和基本鉴赏方法已有所掌握，这一点对学生学习本课是很有利的，但李清照的这两首词如果不了解词人的人生遭遇就很难把握两首词中深层的感情内涵。 针对学生学习本课的不利因素，我安排学生在课前 1.回顾以前学过的李清照的作品 2.查找相关资料了解李清照生平 3.利用早读熟读成诵，初步感知两词。第三部分——教学目标 基于以上教材地位、学情特点以及新课标的要求，我确立了本课的三维教学目标： ①背诵这两首词，因为《语文课程标准》中明确要求学生要背诵一定数量的名篇。 ②通过反复诵读，对比探究，品味意象，体会“闲愁”与“悲愁”的区别，熟悉诗词鉴赏的基本方法，学会知人论世。因《语文课程标准》中要求学生“要加强诵读，在诵读中感受作品的意境和形象，领悟作品的丰富内涵和深层意义”，还提出要培养学生的探究意识，要学习鉴赏诗歌的基本方法，学会知人论世，了解与作品相关的作家经历、时代背景等，加深对作家作品的理解”，依据这两点所以我确立了教学目标二，同时这也是本课的教学重难点。 ③体会真情之美，培养学生对古诗词的热爱及审美情趣。《语文课程标准》中提出“高中语文课程应关注学生情感的发展，培养学生自觉的审美意识和高尚的审美情趣”，因此我确立了教学目标三。 教法与学法 依据教学目标，及《语文课程标准》中“语文教学要为学生创设良好的自主学习情境，倡导自主、合作、探究学习方式”的要求，本课将通过诵读法、情境 法、对比探究法来进行教学，学生通过诵读法、自主合作探究法来学习。 说完了教法与学法，紧接着我将要说的是“教学过程”，分五步走。 第四部分、教学过程 一、新课导入 课前播放《菊花台》歌曲，学生欣赏完我会问：为什么说“菊花残，满地伤”？菊花有什么象征意义？学生对《满城尽带黄金甲》这部电影比较熟悉，可能会想到铺满皇宫的菊花，宫廷军变的失败，生命的凋残消逝??我会顺势总结到：菊花在影片中象征①对已逝辉煌的伤感②对生命凋残的悲悼。“花”这个意象在中国古典诗词中有着深刻的文化内涵，古人有以花
目录 第1章防火墙概述 ..................................................................................................................... 1-1 1.1 网络安全概述 ..................................................................................................................... 1-1 1.1.1 安全威胁.................................................................................................................. 1-1 1.1.2 网络安全服务分类 ................................................................................................... 1-1 1.1.3 安全服务的实现方法................................................................................................ 1-2 1.2 防火墙概述......................................................................................................................... 1-4 1.2.1 安全防范体系的第一道防线——防火墙................................................................... 1-4 1.2.2 防火墙发展历史....................................................................................................... 1-4 1.3 Eudemon产品简介............................................................................................................. 1-6 1.3.1 Eudemon产品系列 .................................................................................................. 1-6 1.3.2 Eudemon500/1000防火墙简介................................................................................ 1-6 1.3.3 Eudemon500/1000防火墙功能特性列表 ................................................................. 1-8第2章 Eudemon防火墙配置基础 .............................................................................................. 2-1 2.1 通过Console接口搭建本地配置环境 .................................................................................. 2-1 2.1.1 通过Console接口搭建 ............................................................................................. 2-1 2.1.2 实现设备和Eudemon防火墙互相ping通 .................................................................. 2-4 2.1.3 实现跨越Eudemon防火墙的两个设备互相ping通.................................................... 2-5 2.2 通过其他方式搭建配置环境................................................................................................ 2-6 2.2.1 通过AUX接口搭建 ................................................................................................... 2-7 2.2.2 通过Telnet方式搭建................................................................................................. 2-9 2.2.3 通过SSH方式搭建 ................................................................................................. 2-11 2.3 命令行接口....................................................................................................................... 2-12 2.3.1 命令行级别 ............................................................................................................ 2-12 2.3.2 命令行视图 ............................................................................................................ 2-13 2.3.3 命令行在线帮助..................................................................................................... 2-24 2.3.4 命令行错误信息..................................................................................................... 2-25 2.3.5 历史命令................................................................................................................ 2-26 2.3.6 编辑特性................................................................................................................ 2-26 2.3.7 查看特性................................................................................................................ 2-27 2.3.8 快捷键.................................................................................................................... 2-27 2.4 防火墙的基本配置............................................................................................................ 2-30 2.4.1 进入和退出系统视图.............................................................................................. 2-30 2.4.2 切换语言模式......................................................................................................... 2-30 2.4.3 配置防火墙名称..................................................................................................... 2-31 2.4.4 配置系统时钟......................................................................................................... 2-31
（封面） 高中语文优秀说课稿范文3篇 授课学科： 授课年级： 授课教师： 授课时间： XX学校
高中语文优秀说课稿范文3篇 高中语文优秀说课稿范文1 一．关于教材： 我所说课的篇目是两千年前的爱国主义诗人屈原的代表作《离骚》，它是高中二年级的教学内容，具体编排在第三册第一单元（古典诗歌） 的第二篇。该单元所选中国古代古体诗8首，其中《诗经》中3首，汉 魏晋五言诗3首，《孔雀东南飞》并序以及《离骚》节选。在该单元中，《离骚》节选占有及其重要的位置。一方面，以屈原的作品为代表的楚 辞是继北方黄河流域出现《诗经》之后，在南方长江流域出现的具有独 特艺术魅力的新诗体，其本身在中国诗歌发展史上具有重要地位；另一 方面，楚辞作品，尤其是屈原的《离骚》从词句的角度看，地方特色鲜明，学生理解的难度较大。 从作品的内容看，《离骚》是一首规模宏伟的政治抒情长诗，全诗373句2400余字，既具有诗人自传的性质，又具有某些幻想性的浪漫主 义成分，整首诗歌感情回环激荡，撼人心魄。课文节选了长诗的第一节，内容主要是诗人自述身世、品质、政治理想以及自己的忠诚不为君王理 解的苦闷之情，表现了屈原坚持“美政”、至死不渝的高尚情操，抒发 了诗人忧国忧民、献身理想的爱国情感。 二．关于教学方法 结合作品特点，按照课程标准对高中阶段在古典诗歌方面阅读能力 的要求，我把《离骚》节选的教学目的确定为以下两点： 一是了解屈原的生平，理解诗人忧国忧民的高尚品质，培养学生的
爱国忧民的思想感情；二是反复诵读，抓住关键词语，疏通诗句，培养学生初步评价鉴赏古典诗歌的能力。学生是学习的主体，每当我们向自己的学生教授新知识的时候，自然要考虑到我们的教学对象在学习本课知识时的原有基础、现有困难及某些学习心理特征，从而有针对性地确定学习的重点、难点及教学对策。高中二年级学生，具有一定的古代诗歌的评价能力，但对于时代久远的楚辞作品，评价的前提――读懂诗歌的内容方面，仍存在困难，根据大纲要求结合学生的实际情况以及本文特点，我确立本文重点及难点如下： 教学重点： 鉴赏重要的语句，感受屈原高尚的人格美。 教学难点： 关键词句的疏通。如何突破重点、难点，有效完成本课的教学任务呢？我决定从教材特点和面临的具体学情出发，首先要把握两个原则：第一，注意高视角、低起点，先把基础知识落到实处，再循序渐进进行教学；第二，重视素质教育，有意识地对学生进行人文素质的培养。 具体教学措施如下： 第一，充分预习。要求学生课下预习，早读检查（内容包括：A作家作品；B写作背景；C掌握生字生词；D熟读课文），逐步培养学生的认知能力和自学能力。 第二，分解重点、难点。本课将分两课时进行，把教学难点，即词句的疏通安排在第一课时中，把教学重点，即作品思想内容的理解安排在第二课时，以确保学生真正做到一课一得。
高中语文说课稿 导读：高中语文优秀说课稿范文1 一．关于教材： 我所说课的篇目是两千年前的爱国主义诗人屈原的代表作《离骚》，它是高中二年级的教学内容，具体编排在第三册第一单元（古典诗歌）的第二篇。该单元所选中国古代古体诗8首，其中《诗经》中3首，汉魏晋五言诗3首，《孔雀东南飞》并序以及《离骚》节选。在该单元中，《离骚》节选占有及其重要的位置。一方面，以屈原的作品为代表的楚辞是继北方黄河流域出现《诗经》之后，在南方长江流域出现的具有独特艺术魅力的新诗体，其本身在中国诗歌发展史上具有重要地位；另一方面，楚辞作品，尤其是屈原的《离骚》从词句的角度看，地方特色鲜明，学生理解的难度较大。 从作品的内容看，《离骚》是一首规模宏伟的政治抒情长诗，全诗373句2400余字，既具有诗人自传的性质，又具有某些幻想性的浪漫主义成分，整首诗歌感情回环激荡，撼人心魄。课文节选了长诗的第一节，内容主要是诗人自述身世、品质、政治理想以及自己的忠诚不为君王理解的苦闷之情，表现了屈原坚持“美政”、至死不渝的高尚情操，抒发了诗人忧国忧民、献身理想的爱国情感。 二．关于教学方法 结合作品特点，按照课程标准对高中阶段在古典诗歌方面阅读能力的要求，我把《离骚》节选的教学目的确定为以下两点：
一是了解屈原的生平，理解诗人忧国忧民的高尚品质，培养学生的爱国忧民的思想感情；二是反复诵读，抓住关键词语，疏通诗句，培养学生初步评价鉴赏古典诗歌的能力。学生是学习的主体，每当我们向自己的学生教授新知识的时候，自然要考虑到我们的教学对象在学习本课知识时的原有基础、现有困难及某些学习心理特征，从而有针对性地确定学习的重点、难点及教学对策。高中二年级学生，具有一定的古代诗歌的评价能力，但对于时代久远的楚辞作品，评价的前提――读懂诗歌的内容方面，仍存在困难，根据大纲要求结合学生的实际情况以及本文特点，我确立本文重点及难点如下： 教学重点： 鉴赏重要的语句，感受屈原高尚的人格美。 教学难点： 关键词句的疏通。如何突破重点、难点，有效完成本课的教学任务呢？我决定从教材特点和面临的具体学情出发，首先要把握两个原则：第一，注意高视角、低起点，先把基础知识落到实处，再循序渐进进行教学；第二，重视素质教育，有意识地对学生进行人文素质的培养。 具体教学措施如下： 第一，充分预习。要求学生课下预习，早读检查（内容包括：A 作家作品；B写作背景；C掌握生字生词；D熟读课文），逐步培养学生的认知能力和自学能力。
防火墙技术是安全技术中的一个具体体现。防火墙原本是指房屋之间修建的一道墙，用以防止火灾发生时的火势蔓延。我们这里讨论的是硬件防火墙，它是将各种安全技术融合在一起，采用专用的硬件结构，选用高速的CPU、嵌入式的操作系统，支持各种高速接口（LAN接口），用来保护私有网络（计算机）的安全，这样的设备我们称为硬件防火墙。硬件防火墙可以独立于操作系统（HP-UNIX、SUN OS、AIX、NT等）、计算机设备（IBM6000、普通PC等）运行。它用来集中解决网络安全问题，可以适合各种场合，同时能够提供高效率的“过滤”。同时它可以提供包括访问控制、身份验证、数据加密、VPN技术、地址转换等安全特性，用户可以根据自己的网络环境的需要配置复杂的安全策略，阻止一些非法的访问，保护自己的网络安全。 现代的防火墙体系不应该只是一个“入口的屏障”，防火墙应该是几个网络的接入控制点，所有进出被防火墙保护的网络的数据流都应该首先经过防火墙，形成一个信息进出的关口，因此防火墙不但可以保护内部网络在Internet中的安全，同时可以保护若干主机在一个内部网络中的安全。在每一个被防火墙分割的网络内部中，所有的计算机之间是被认为“可信任的”，它们之间的通信不受防火墙的干涉。而在各个被防火墙分割的网络之间，必须按照防火墙规定的“策略”进行访问。
防火墙发展至今已经历经三代，分类方法也各式各样，例如按照形态划分可以分为硬件防火墙及软件防火墙；按照保护对象划分可以分为单机防火墙及网络防火墙等。但总的来说，最主流的划分方法是按照处理方式进行分类。 防火墙按照处理方式可以分为以下三类： 包过滤防火墙 包过滤是指在网络层对每一个数据包进行检查，根据配置的安全策略转发或丢弃数据包。包过滤防火墙的基本原理是：通过配置访问控制列表（ACL, Access Control List）实施数据包的过滤。主要基于数据包中的源/目的IP地址、源/目的端口号、IP 标识和报文传递的方向等信息。 包过滤防火墙的设计简单，非常易于实现，而且价格便宜。 包过滤防火墙的缺点主要表现以下几点： 1. 随着ACL 复杂度和长度的增加，其过滤性能呈指数下降趋势。 2. 静态的ACL 规则难以适应动态的安全要求。