ShareCam Part I:Interface,System Architecture,and Implementation of
a Collaboratively Controlled Robotic Webcam?
Dezhen Song and Ken Goldberg
IEOR and EECS Departments,UC Berkeley,United States
ShareCam is a robotic pan,tilt,and zoom web-based camera controlled by simultaneous frame requests from on-line users.A companion paper1describes algorithms.This paper,Part I,focuses on the system.Robotic webcameras are commercially available but currently restrict control to only one user at a time.ShareCam introduces a new inter-face that allows simultaneous control by many users.In this Java-based interface,participating users interact from their remotely located browsers where users draw desired frames over a?xed panoramic https://www.doczj.com/doc/6d14810718.html,er inputs are transmitted back to a pair of PC servers that compute optimal camera parameters,servo the camera,and provide a video stream to all users.We describe the system and compare results with two frame selection models based on user“satisfac-tion,”one memoryless and the second based on satisfaction over multiple motion cycles.ShareCam can be tested online at:https://www.doczj.com/doc/6d14810718.html,/sharecam/
1Introduction
Robotic webcameras with pan,tilt,and zoom controls are now commercially available and are being installed in dozens of locations2around the world.In these systems, the camera parameters can be remotely adjusted by view-ers via the Internet to observe details in the scene.Current control methods restrict control to one user at a time;users have to wait in a queue for their turn to operate the cam-era.In this paper we describe ShareCam,a new approach that eliminates the queue and allows many users to share control of the robotic camera simultaneously.
As illustrated in Figure1,the ShareCam system includes the camera and two servers that communicate with users via the Internet.Streaming video is captured at the cam-era server and streamed back to the remote users using a ?Submitted IEEE/RSJ International Conference on Intelligent Robots and Systems,Oct.2003.This work was supported in part by the National Science Foundation under IIS-0113147,by Intel Corporation,by Microsoft Corporation,and in part by UC Berkeley’s Center for Information Technology Research in the In-terest of Society(CITRIS).For more information please contact dzsong@https://www.doczj.com/doc/6d14810718.html, or goldberg@https://www.doczj.com/doc/6d14810718.html,.
1The paper ShareCam Part II:Approximate and Distributed Algorithms has been submitted separately to this conference,and can be found at https://www.doczj.com/doc/6d14810718.html,/sharecam/pubs
2See:
http://www.x-zone.canon.co.jp/WebView-E/index.htm
Figure1:ShareCam System Architecture.
Java https://www.doczj.com/doc/6d14810718.html,er responses are collected at the Share-Cam server and used to compute optimal camera positions, which are sent to camera server to control the camera. ShareCam’s Java-based interface includes two image windows,one?xed for user input and the other a live streaming video image.The interface collects requested camera frames(speci?ed as a desired rectangle)from n users,computes a single camera frame based on all inputs, and moves the camera accordingly.Below we describe sys-tem details and two frame selection models based on user “satisfaction.”
2Related Work
ShareCam is an example of Collaborative Telerobotics,in this case the telerobot is a camera with3degrees of free-dom.In the taxonomy proposed by Tanie et al.[7],Share-Cam is a Multiple Operator Single Robot(MOSR)sys-tem.Collaborative Telerobotics is motivated by applica-tions such as education and journalism,where groups of users desire simultaneous access to a single robotic re-source.Inputs from each user are combined to generate a single control stream for the robot.
The Internet provides a low-cost and widely-available in-terface that can make physical resources accessible to a broad range of participants.There are now thousands of we-bcams,dozens of“online robots”,a book from MIT Press
[14],and an IEEE Technical Committee on Internet and On-line Robots.
Online robots,controllable over the Internet,are an active research area.In addition to the challenges associated with time delay,supervisory control,and stability,online robots must be designed to be operated by non-specialists through intuitive user interfaces and to be accessible24hours a day; see[16,17,20,19,22,25,28,29,36]for examples of recent projects.
Tanie,Matsuhira,Chong,et al.[7]proposed the fol-lowing taxonomy for teleoperation systems:Single Oper-ator Single Robot(SOSR),Single Operator Multiple Robot (SOMR),Multiple Operator Multiple Robot(MOMR).and Multiple Operator Single Robot(MOSR).Most online robots are SOSR,where control is limited to one operator at a time.Tanie et al.analyzed an MOMR system where each operator controls one robot arm and the robot arms have overlapping workspaces.They show that predictive displays and scaled rate control are effective in reducing pick-and-place task completion times that require cooper-ation from multiple arms.
A number of SOSR systems have been designed to facil-itate remote interaction.Paulos and Canny’s Personal Rov-ing Presence(PRoP)telerobots,built on blimp or wheeled platforms,were designed to facilitate remote social interac-tion with a single remote operator[30,31].Fong,Thorpe and colleagues study SOSR systems where collaboration occurs between a single operator and a mobile robot that is treated as a peer to the human and modeled as a noisy information source[11].Related models of SOSR“cobots”are analyzed in[1,3,11,26,38].
In an MOMR project by Fukuda,Liu,Xi,and colleagues [10],two remote human operators collaborate to achieve a shared goal such as maintaining a given force on an object held at one end by a mobile robot and by a multi-jointed robot at the other.The operators,distant from the robots and from each other,each control a different robot via force-feedback devices connected to the Internet.The authors show both theoretically and experimentally that event-based control allows the system to maintain stable synchroniza-tion between operators despite of variable time-lag on the Internet.
MOMR models are also relevant to online collaborative games such as Quake,where players remotely control indi-vidual avatars in a shared environment.
In SOMR systems,one tele-operator or process con-trols multiple robots.This bears some relation to Coopera-tive(behavior-based)robots,where groups of autonomous robots interact to solve an objective[2].Recent results are reported in[5,9,35,33].
One precedent of an online MOSR system is described in McDonald,Cannon and colleagues[27].For waste cleanup,several users assist in waste cleanup using Point-and-Direct (PAD)commands[6].Users point to cleanup locations in a shared image and a robot excavates each location in turn. In this Internet-based MOSR system,collaboration is serial but pipelined,with overlapping plan and execution phases. The authors demonstrate that such collaboration improves overall execution time but do not address con?ict resolution between users.
In[12]Goldberg and Chen analyze a formal model of collaborative control and in[13]describe Internet-based MOSR system that averaged multiple human inputs to si-multaneously control a single industrial robot arm.In[15] we propose the“Spatial Dynamic V oting”(SDV)interface. The SDV collects,displays,and analyzes a sequence of spa-tial votes from multiple online operators at their Internet browsers.The votes drive the motion of a single mobile robot or human“Tele-Actor”.
Research on controllable webcams or Internet cameras are focus on two perspectives:system architectures and ap-plications.Desmet,Verkest,Mignolet et al.[8,18,40] designed webcams using recon?gurable hardware and em-bedded software.They implemented a secure VPN(Virtual Private Network)with3DES encryption and Internet cam-era server(including JPEG compression).Brooks and Mc-Kee[4]implemented an automated camera which is placed during teleoperation using Visual Acts theory and architec-ture to provide operators with task relevant information in a timely manner.The applications of webcams is not lim-ited to surveillance[21]or teleconferencing[23,24,32]. Schmid,Maule,and Roth[37]used a controllable webcam to perform all the tests for industrial robots given by ISO 9283“Performance criteria and related test methods”.Pol-lak and Hutter[34]installed a Phillips webcam on an Olym-pus BX60light microscope to record movies of investigated samples.Zhang,Navab,and Liou[41]used webcams to creat an interactive sales model for web customers.
In independent work,Kimber,Liu,Foote et al describe a multi-user robot camera in[23,24].The application is designed for videoconferencing system.They use multi-ple cameras in the systems:panoramic cameras and a pan-tilt-zoom camera.Panoramic cameras generate a dynamic panoramic view of the conference https://www.doczj.com/doc/6d14810718.html,ers control the pan-tilt-zoom camera by drawing on panoramic view.The system is well suitable for videoconferencing environment, where illumination condition is constantly good so that the image quality of panoramic view can be guaranteed.We believe multiple camera systems are good but not necessary for scenic sites where dynamic information is not neces-sary.The panoramic image can be generated by the same pan-tile-zoom camera resulting in less bandwidth require-ment.
An earlier paper[39],published in the Workshop on Al-
Figure2:This?gure illustrates ShareCam’s Java-based user interface,which currently runs on most Windows based PCs. Users view two windows.One(not shown)displays a live video stream as captured by the robotic camera.The second window,illustrated here,contains the user interface.The panoramic image is a?xed photo of the camera’s reachable range of view.The snapshot above shows4active users listed in the scrollable window at the left.Each user requests a camera frame by positioning a dashed rectangle over the panoramic image.Based on these requests,the algorithm computes an optimal camera frame(shown with solid rectangle),and servoes the camera accordingly to displays the resulting live video stream.The horizontal bars indicate levels of user satisfaction as described below.The system is installed in our research lab at Berkeley but will be moved outdoors in April2003.
gorithmic Foundations of Robotics,formulated the Share-Cam problem geometrically and reported initial results on exact algorithms:for n users and m zoom levels,the ex-act algorithm runs in O(n2m)time.That paper is available online.3
3ShareCam Interface
The ShareCam interface facilitates interaction and collabo-ration among remote https://www.doczj.com/doc/6d14810718.html,ers register online to partici-pate by selecting a characteristic color and submitting their email address to the ShareCam server,which stores this in-formation in our database and immediately sends back a password via email.The server also maintains a tutorial and an FAQ section to familiarize new users with how the systems works.
The ShareCam interface contains two windows:The video window shows the current camera view.Figure2 illustrates the panoramic window and the ShareCam user interface.
The interface also facilitates chat between users.Each user can type in a short sentence,which is displayed under-neath his/her requested frame in the panoramic image.A clocklike timer is located at the bottom right of the inter-3https://www.doczj.com/doc/6d14810718.html,/goldberg/pubs/face indicating the time before the next camera movement (typically5-10seconds).
4Hardware
The ShareCam server is a AMD K7950Mhz PC with1.2GB memory connected to a100Mbs T3line.The camera server is a AMD K7950Mhz PC with640MB memory connected to a100Mbs T3line at the remote site.It has a video-capture card,which captures video at320×240resolution. It also serves as video server running InetCam4software to broadcast video.
We used the Canon controllable camera,model VC-C3.
A comparable camera is available from Sony.The Canon camera has motorized pan,tilt and zoom with10x power zoom lens.It has PAL,composite,and S-video output with a resolution of450horizontal lines.It can communicate with a PC via a RS232C link at14,400bps.Its pan,tilt,and zoom speed is76degree per second at maximum and0.5 degree per second at minimum.It has an accuracy of0.5 degree and a380,000pixel CCD array.
5Software
As illustrated in Figure3,custom software includes:(1)the ShareCam server,(2)the camera control software and video 4https://www.doczj.com/doc/6d14810718.html,
Figure3:ShareCam system software diagram. capturing package at the video server,and(3)the client side
ShareCam Java applet.
The ShareCam server runs Redhat Linux7.1and the Apache web server1.3.20.All modules are written in GNU C++with optimization of running speed.The Share-Cam server package consists of core process,Apache mod-ules,communication process,user databases,registration module,console/log module,and login CGI script.The customized Apache module deals with communication be-tween web clients and the server via HTTP.It accepts the re-quested frame from a client and sends him/her the requested frames of others every second.It can be viewed as a CGI script but with much higher scalability.The communication module connects video server via a socket link to send cam-era control commands.A console/log module allows us to monitor and record system status in real time.
The overall design emphasizes data sharing among all processes.Collaborative control requires all clients are able to see each other’s information in real time.This is achieved by sharing memory segments among all server processes. Therefore the shared memory segment managed by the core process is the key data structure.
Clients download two applets:the ShareCam applet and the InetCam applet.The ShareCam applet is a customized software,which is show in Figure2.Part of the frame se-lection computation is done at the client side,which is im-plemented in the ShareCam applet.The ShareCam applet is written in Java1.1to ensure the compatibility with most browsers.The InetCam applet is a third party software that functions as a video terminal.
The video server package includes camera control,In-etCam server,calibration,and panoramic image generation. The camera control module written in Microsoft Visual C++is the primary module.It accepts camera control commands from the ShareCam server and translate it into RS232C pro-tocol,which is built on packages provided by Lawrence Berkeley National Laboratory5.
6Experiments
In this section,we will present experimental results for two frame selection models.We begin with a review of de?ni-tions and notation.More details can be found in the com-panion paper:Part II.
6.1Two Frame Selection Models
In the ShareCam system,φis a vector of camera param-eters that users can control.Letφde?ne a camera frame [x,y,z],where x,y specify the center point of the frame, which is corresponding to pan and tilt,and z speci?es size of the frame,which corresponds to zoom level.φde?nes a rectangular camera frame(the camera has a?xed aspect ratio of4:3).User i requests a desired frameφi.Given re-quests from n users,the system computes a single global frameφ?that will best satisfy the set of requests.
We de?ne a Generalized Intersection Over Maximum (GIOM)metric for user“satisfaction”s(φ,φi)based on how the user’s requested frameφi compares with a can-didate camera frameφ.Each of n users submits a request. Let
s(φ)=
n
i=1
s i(φi,φ)(1)
In the memoryless frame selection model,we want to?nd φ?,the value ofφthat maximizes s(φ)based only on the current set of requests:
max
φ
s(φ).
In each motion cycle,we servo the camera to this frame. An alternative frame selection is model based on user sat-isfaction over multiple motion cycles.We extend equation 1using a weighted sum of the satisfaction over multiple cy-cles.In this case total satisfaction is a function of time t:
s(φ,t)=
n
i=1
αi(t)s i(φi(t),φ(t))(2)
where the weightαi(t)for user i is a function of the user’s previous“dissatisfaction”level:u i(t)=1?s i(φi(t),φ(t)). One candidate form forαi(t)is,
αi(t)=
t?1
k=0
u i(k)
2t?1?k
5https://www.doczj.com/doc/6d14810718.html,/mbone/devserv/
which gives the recursive formulation:
αi(t)=u i(t?1)+αi(t?1)/2
If user i is not satis?ed in one motion cycle,that user’s weightαi(t),will increase over future motion cycles,even-tually dominating the requests of other users to achieve fair-ness.
These optimization problems can be solved using the ap-proximation algorithms presented in Part II or with the exact algorithms presented in [39].
Figure4:Examples of frame selection using the memoryless frame selection de?ned by equation1.
Figure4shows four examples with memoryless frame selection.Figure4(a)indicates the algorithm functions like a combination of“clustering”for rectangles with different location and size and an algorithm that identi?es the region of panoramic view with the highest requested frame den-sity.It is interesting to see that the optimal frame grows in image(b)after a large frame is requested.In Figure4(c), two more frames are requested.Since they can not com-pete with the central group of requested frames,the optimal frame remains unchanged.Figure4(d)shows a case with
all but two requested frames disjoint,the algorithm selects a frame that covers the two overlapping frames.
Figure4also says that minority users are not satis?ed if using problem de?nition given by equation1.A weighted sum format in equation2that keeps track of user unsatis-faction level is more preferable.
Figure5illustrates the results when frame selection is based on user satisfaction over multiple motion cycles.A sequence of4motion cycles is illustrated.Even though the user requested frames are unchanged,the camera frame changes to balance overall user satisfaction over
time. Figure5:Examples of frame selection over multiple motion
cycles de?ned by equation2.
6.2Online experiments
As of submission date,the system is fully functional an on-line at the url given in the Abstract.We are currently col-lecting user statistics.
7Conclusions and Future Work
This paper describes the ShareCam,a MOSR teleoperation system that allows a group of Internet users to simultane-ously share control of a pan,tilt,and zoom camera.We described the ShareCam interface,system architecture,and experiments with two frame selection models. Currently,the panoramic image generation is done by off-line by hand using Photoshop.In future work we will develop an automatic procedure for creating and calibrating the panoramic image.
A preliminary version of the ShareCam went online in Sep.2002in our lab in Berkeley.The sytem may be of?ine for a short period in April as we move the camera to an outside campus location for testing. Acknowledgments
We are grateful to Frank van der Stappen,Sariel Har-Peled, Vladlen Koltun,Dana Plautz,Cory Cox,and Eric Paulos for insightful discussions and feedback.Thanks to M.Faldu and W.Guan for their contributions to the ShareCam system,and I.Y.Song,K.“Gopal”Gopalakrishnan,Ron Alterovitz, A. Levandowski,M.Mckelvin,A.Ho,and J.Vidales for helpful sug-gestions.
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雅思口语part2话题万能模板：事件类今天三立在线教育雅思网为大家带来的是雅思口语part2话题万能模板：事件类的相关资讯，备考的烤鸭们，赶紧来看看吧！ 首先我们来说说“一件从数学中学到的事情”，拿到这个话题，先不要急着回答，可以用笔稍微构思一下思路，该怎么回答。首先，可以说一下这件事是什么、发生在什么时候，也就是作文中的事件和事件，这里需要注意的就是具体描述一下什么事但是又不能啰嗦累赘，而时间则可以大致概括点明即可。我们就从资料中的例子来说：高中的时候从乘法表中学到的一件事。 然后，要具体叙述一下这件事，即是最重要的部分，发生的地方、牵扯到的人物、以及这件事情影响到你的原因，为什么影响到你…… 资料例子来说：在高中的一次数学竞赛中失败，以至于灰心丧气，甚至对自己产生怀疑，而此时数学老师拿乘法的规则来比喻人生中的失败与成功的关系来鼓励我，以至于我从失败中走出来，从新赢得了下一次的数学竞赛。这件事情使我明白了，生活就如同数学乘法，有无数种可能，多种多样，我们要坦然面对。 而这里的例子看似像我们中文作文中的思路，但是关键在于它表述方式以及用词造句，不能太中式化。这里的重点，就是描述事件经过，即“在高中的一次数学竞赛中失败，以至于灰心丧气，甚至对自己产生怀疑，而此时数学老师拿乘法的规则来比喻人生中的失败与成功的关系来鼓励我，以至于我从失败中走出来，从新赢得了下一次的数学竞赛。”而老师的话则是重中之重，因为他让我明白了道理“生活就如同数学乘法，有无数种可能，多种多样，我们要坦然面对。”也是我深深牢记的原因，以及这件事对我影响深刻的原因。
而最后，只需要简单概括，从这件事中学到的东西即可。其实这个话题思路并不是很难，关键在于烤鸭们的表述以及词汇的积累。 其实，大家都知道事件类话题是雅思口语考试中最简单的、最容易描述，却也是最常见的话题，所以大家要多注意积累素材、思考思路。其实“A way of communication”和“A good parent”这两个话题也可以用这个例子来阐述回答，而最关键的则是把老师的那段话稍作转述即可。例如，“A way of communication”我们可以先描述手机及其性能作用，以及现今的流行趋势，然后从一件事引到交流方式，还是那件事，还是那写话，只不过要突出老师用短信的方式告知我，最后，简单概述手机的用处及好处即可。是不是很简单呢?同样的，“A good parent”只需要根据情况把那些话转述为父母亲对你说的话，已经对你的影响，所以一个模板真的是百用哦! 那么我们赶紧来看看还有哪些话题可以这样转换呢? 多米诺骨牌效应：=Something you learned from math=Something you learned from your family=A piece of advice=A change you had=An important stage in your life=A text message you got=A letter you got=An E-mail you got=A way of communication=An important decision you made=A person who helped you=A kind thing someone did to you=A family member you love talking to=A good parent=An elderly family member=A neighbor=A good friend=A teacher=A science course you took=A subject you love/d at school=Your personality=First day of college=Your experience of getting money as a gift=Your experience of getting congratulations=A person you helped=A thing your friend did made you admire.
play a part (in) 重要程度：★☆☆☆☆难易程度：★★☆☆☆ Have you realized the part computers have ___________ in the daily life? A. made B. given C. caused D. played 【参考答案】D 【拓展延伸】 1. play a part (in) 在……中扮演一个角色；参与；在……中起作用 2. play the role of 扮演……的角色 play an important role / part in...在……中起重要作用 play the leading role / part主演；起带头作用 3. take part in 参加 for the most part多半；在很大程度上 for one’s part就某人而言，对某人来说 1. Colors play an important ___________ in the way you look. A. part B. form C. effect D. pride 2. Mr. Huang will ___________ in the movement. A. play a leading part B. take parts C. play leading part D. take a part 3. __________ part that women ___________ in society is great. A. The; plays B. A; takes C. A; plays
雅思口语part2中不建议背诵范文 背诵的痕迹如果比较明显在雅思口语中是很不利的，下面一起来看看有哪些需要注意的吧！ 雅思口语part 2中不建议背诵范文 有很多同学常常觉得雅思口语考试从6分到7分是一个不可逾越的鸿沟，其实大家如果能够将自己的语言丰富一些，细节描述更多一些，获得7分以上，还是很有机会的。 对于一些描述性的雅思口语part 2题目，不少同学表示可说的内容比较少，所以在2分钟之内的表达显得干巴巴的，没有什么实质性的东西。事实上，如果能够提升自己对于细节的专注程度，在part 2的考试中能够令人眼前一亮。 我们以“描述你在特殊场合穿着的衣服”这个话题为例。如果仅仅描述一件衣服，那么可说的内容很少。但是如果我们更加专注于如何描述这件衣服的背景和增添一些比较地道的描述，那么实际的效果是大不相同的。仅以下文为例，供广大考生参考。 Describe a piece of clothing you wear on a special occasion Key points：Graduation，school，pink dress，accessory， Actually，in my high school，students are required to wear the school uniforms each day at school. Everyone looks the same to a great extent.【程度的描述】No one's special. So after a while，we all have the similar physical features. Baggy pants，oversized jackets，and big glasses on our faces，【生动的描述】of course【的语序】. Lucky enough【选取比较自然的连接词】，we had a graduation ceremony，and the high school allowed us to wear something casual 【转换词性】on that very day. For this special day，I picked up a really nice dress. My mum and I found it at an elegant shopping mall，which was stunning in the store window.【还是细节描写，而且增添了背景故事】I had my eyes on that dress immediately. It was a pink dress with a black leather belt，which was neither too fancy nor too formal.【加入形容的部分】It boasts an graceful cutting style with a U-neck shape. Somehow，it reminded me of a typical Chanel dress.【加入了西方背景知识】My mum said it might be too mature for my age，but I believe it was OK.【自然
网页制作必懂的基础知识（一） 近来这几天一直在学习网页制作的知识，颇有收获，分享大家，都是一些网页制作的必懂的基础知识。 1 html基础代码
== 可以创建链接和瞄点。 特殊标签：空格 大于号：>小于号：<版权号：© 引号：" 滚动标签: 属性有：滚动方向和滚动次数direction:left;right;up;down; loop 鼠标放上去停止滚动：onmouseover=this.stop() 鼠标离开继续滚动：onmouseover=this.start() 2图片的讲解雅思口语万能模板 今天给大家收集了雅思口语万能模板，快来一起学习吧,下面就和大家分享，来欣赏一下吧。 雅思口语万能模板：自我介绍Sample Sample1: My name is ________. I am graduate from ________ senior high school and major in ________. There are ________ people in my family. My father works in a computer company. And my mother is a housewife. I am the youngest one in my family. In my spare time, I like to read novels. I think reading could enlarge my knowledge. As for novels, I could imagine whatever I like such as a well-known scientist or a kung-fu master. In addition to reading, I also like to play PC games. A lot of grownups think playing PC games hinders the students from learning. But I think PC games could motivate me to learn something such as English or Japanese.My favorite course is English because I think it is interesting to say one thing via different sounds. I wish my English could be improved in the next four years and be able to speak fluent English in the future.
play a part in的用法 Do you know this pretty girl Right! She is Audrey Hepburn who played many classic roles in a great many famous films. For example, < Roman Holiday> is the one of the films which earned Hepburn her first Academy Award for Best Actress. Audrey Hepburn played the part/role of Princess Ann in this film. play the part/role of…扮演……角色
Audrey Hepburn played a leading part in
Audrey Hepburn also played leading roles in < Funny Face>and < My Fair Lady〉.( My Fair Lady 窈窕淑女影片讲述下层卖花女被语言学教授改造成优雅贵妇的故事，从头至尾洋溢着幽默和雅趣 .Funny Face 甜姐儿) Play a role in…在……中扮演角色，在……中起作用 play a part/role in doing sth. 在做某事方面起作用,参与做某事 We can?all?play?a?role/part?in?reducing?our?dependence?on?plastic, if we started to?take some small?steps?in?our?everyday?lives?to?be
小黑雅思口语万能连接词地点描述 Like I’m fairly keen on… I’m really into… I’m quite a big fan of… I simply adore… I’m quite enthusiastic/passionate about… I generally prefer…to… I’m pretty fond of … I’m totally mad about… I’m obsessed with… I’m fascinated by… dislike I’m not so keen on… I’m really not that fond of … I’m not much of a fan of… I really cant stand… 迅速回答 Well, actually… Sure, obviously… Ok, certainly… Of course, you know… Of course, it goes without saying that…不确定 I think I would have to say that it really depends. Well, quite honestly I don’t think I’ve ever thought about hat, but I guess…Actually, this isn’t something that I’ve ever considered, but in short… I’m not really sure how to put this, but I suppose generally speaking… 种类 There’s quite a mixed variety of …There’s quite a wide range of… There’s fairly broad range of… There’s quite an extensive diversityof …There’s quite a diverse mixture of… 虚拟语气 If I lived in Mediterranean, I would/could/might…… 假设 If …, then I will most likely do….
分享常用的雅思口语句型模版 本文三立在线老师为大家整理了一些雅思口语模板句型，希望同学们都能取得好成绩。 I get up at six o''clock.我六点起床。 I meet the boss himself.我见到了老板本人。 I owe you for my dinner.我欠你晚餐的钱。 I really enjoyed myself.我玩得很开心。 I''m fed up with my work !我对工作烦死了! It''s no use complaining.发牢骚没什么用。 She''s under the weather.她心情不好。 The child sobbed sadly. 小孩伤心地抽泣着。 The rumor had no basis. 那谣言没有根据。 They praised him highly.他们大大地表扬了他。 Winter is a cold season.冬天是一个寒冷的季节。 You can call me any time. 你可以随时打电话给我。 What shall we do tonight?我们今天晚上去干点儿什么呢? What''s your goal in life?你的人生目标是什么? When was the house built?这幢房子是什么时候建造的? Why did you stay at home?为什么呆在家里? Would you like some help?需要什么帮助吗?
You mustn''t aim too high你不可好高骛远。 You''re really killing me!真是笑死我了! You''ve got a point there. 你说得挺有道理的。 Being criticized is awful !被人批评真是痛苦! 15 divided by 3 equals 5.15 除以3 等于5. All for one ，one for all.我为人人，人人为我。 East，west，home is best. 金窝，银窝，不如自己的草窝。 He grasped both my hands. 他紧握住我的双手。 He is physically mature.他身体已发育成熟。 I am so sorry about this. 对此我非常抱歉(遗憾)。 以上是三立在线老师带来的关于分享常用的雅思口语句型模版的详细内容，希望各位考生能从中受益，并不断改进自己的备考方法提升备考效率，从而获得理想的考试成绩。
web 一、超文本（hypertext） 一种全局性的信息结构，它将文档中的不同部分通过关键字建立链接，使信息得以用交互方式搜索。它是超级文本的简称。 二、超媒体（hypermedia） 超媒体是超文本（hypertext）和多媒体在信息浏览环境下的结合。它是超级媒体的简称。用户不仅能从一个文本跳到另一个文本，而且可以激活一段声音，显示一个图形，甚至可以播放一段动画。 Internet采用超文本和超媒体的信息组织方式，将信息的链接扩展到整个Internet上。Web就是一种超文本信息系统，Web的一个主要的概念就是超文本连接，它使得文本不再象一本书一样是固定的线性的。而是可以从一个位置跳到另外的位置。可以从中获取更多的信息。可以转到别的主题上。想要了解某一个主题的内容只要在这个主题上点一下，就可以跳转到包含这一主题的文档上。正是这种多连接性把它称为Web。 三、超文本传输协议（HTTP）Hypertext Transfer Protocol超文本在互联网上的传输协议。 IP IP是英文Internet Protocol（网络之间互连的协议）的缩写，中文简称为“网协”，也就是为计算机网络相互连接进行通信而设计的协议。在因特网中，它是能使连接到网上的所有计算机网络实现相互通信的一套规则，规定了计算机在因特网上进行通信时应当遵守的规则。任何厂家生产的计算机系统，只要遵守IP协议就可以与因特网互连互通。IP地址具有唯一性，根据用户性质的不同，可以分为5类。另外，IP还有进入防护，知识产权，指针寄存器等含义。 http 超文本传送协议(HTTP) 是一种通信协议，它允许将超文本标记语言(HTML) 文档从Web 服务器传送到Web 浏览器。HTML 是一种用于创建文档的标记语言，这些文档包含到相关信息的链接。您可以单击一个链接来访问其它文档、图像或多媒体对象，并获得关于链接项的附加信息。HTTP工作在TCP/IP协议体系中的TCP协议上。 FTP FTP（File Transfer Protocol, FTP）是TCP/IP网络上两台计算机传送文件的协议，FTP是在TCP/IP网络和INTERNET上最早使用的协议之一，它属于网络协议组的应用层。FTP客户机可以给服务器发出命令来下载文件，上载文件，创建或改变服务器上的目录。 第一、什么是C/S结构。 C/S （Client/Server）结构，即大家熟知的客户机和服务器结构。它是软件系统体系结构，通过它可以充分利用两端硬件环境的优势，将任务合理分配到Client端和Server端来实现，降低了系统的通讯开销。目前大多数应用软件系统都是Client/Server形式的两层结构，
万能雅思口语话题高分模板句今天三立在线教育雅思网为大家带来的是万能雅思口语话题高分模板句的相关资讯，备考的烤鸭们，赶紧来看看吧！ 遇到口语新题卡壳时，你需要这些句子 1. This is a tough question. I have never heard about it, nor have I ever read about it (倒装句丰富句型). 2. Give me a few seconds for me to search every piece of information in my head now. 3. It is an abstract question. I know little about it. 4. Are you asking me something about+你重复一下句子中的关键词…? 5. Have I given enough information? It would be great if you could give me more. 6. Am I making myself clear? 7. Now you want me to talk about it. But I don't have too much to say. 8. Give me a few seconds for me to organize my thought a little bit. 遇到话题来不及思考是，你需要一些简单过渡词 如果你不需要这么长的思考时间，你可以说这些简单的过渡词： 1.“well” 2.“you know” 3.“actually”
网页制作基础知识教案 教学目标： 了解网页的组成元素及常用的网页制作工具。了解网页制作的一些基础知识，如网站和网页的区别、网页的类型、网页的构成元素等，然后在了解的基础上再通过练习来巩固。 教学重点难点： 在深刻了解概念的基础上把理论转化成实际的应用。 教学过程： 在制作网页之前，首先要了解一些关于web网页的基本知识，了解一下构成一个网站的基本元素等。 网页的基本元素 文本：基本组成部分 图像：更加直观准确地表达某些信息，并且可以起到美化网页，吸引读者注意力的作用 超链接：可以方便地转入其他网页进行浏览。 网页的其他元素：音乐表格表单 美化网页，丰富网页的内容，增强网页的功能。 网页的实质 网页相当于刊物中所发表的一篇篇文章，但与纸上的文章相比，它增加了多媒体信息和网上交互的功能。 网页的实质 = 表格+文本+图片+动画+声音+超级链接+…… ◆网站相当于发行到全世界的期刊。 ◆网站的实质 = 服务器上的文件夹 ◆主页相当于期刊的封面。 ◆主页的实质 = 打开网站的第一个网页 网页和网站的分类 从网页是否执行程序来分，可分为静态网页和动态网页这两种类型。 什么是静态网页、动态网页? ◆所谓静态网页，指的是网页从服务器传到客户端时，网页的内容是“固定 不变”的，也就是说，服务器只是把所存储的网页的内容原封不动直接传递给客户端浏览器，这种网页一般是标准的HTML代码。 静态网页一般以.htm或.html为后缀结尾的，俗称html文件。本课程就是制作静态网页的课程。 ◆所谓动态网页，它在由服务器传递给客户端的时候必须由服务器把它转换 成相应的HTML格式，而且会根据用户的要求和选择在在服务器端做出相应的改变和响应。 动态网页一般要用专门的脚本语言编写，如ASP、https://www.doczj.com/doc/6d14810718.html,、PHP、JSP等等
Part1 介绍自己的姓名： My Chinese name is Ma Jiantong .which was given by my father , meaning a health &strong body 介绍学校： I am a student major in science in No 2 senior school in Mu Danjiang which is famous in HLJ province 介绍家乡： Just before a few days there are 5 people in my family , but now, there only 4 . I would like to say it is really a typical chinese family ,namely my grandmother ,my parents and I . my grandmother was a worker is retired. My father is a middle school teacher and he has been teaching English for approximately 30 years . my mother was once a chemist ,is also retired and I am a senior high student preparing the college entrance examination . my grandfather just pasted away .which means that I have a clear ,distinct memory of him . 关于“我喜欢”的表达： 1. There are a lot of ….;but …..being my favorite all the time . 2. I am really keen on… 3. I am passionate a bout….. 开头句： 1. Well in general I would say that…. 2. Well to be honest I would really to say tha…. 3. Certainly I would definite say that…. 连接词： 1. to be more accurate 2. in addition to this … 3. I suppose the reason has something to do with the f act that…. 关于“类型”的回答： 1. There is quite a wide range of….. 2. There is quite an extensive diversity of… 3. I assume …. are so + adj. because……. Part 2 卡片上的问题回答要有顺序，在用铅笔标明信息时，应该注明所要叙述的要点，越简洁越好，另外要选好时态 开场语句： 1. All right then , in response to the first question of …… 2. Initially then ,I would like to get started by look at….. 回答第二题： 1. Continuing then with the next point of… 2. Now with regard to the next question of…… 回答第三题： 1. Moving onto the business of…… 2. Drawing attention to the matter of…. 3. What I would like to make clear is that….
Unit 7 Will people have robots?知识 点整理 Unit7willpeoplehaverobots?知识点整理 一、词组、短语： 、oncomputers在电脑上， 2、onpaper在纸上， 3、livetobe200yearsold活到200岁， 4、freetime空闲时间， 5、indanger 在危险中， 6、ontheearth在世界上 7、playapartinsth在某方面出力/做贡献， 8、spacestation太空站， 8、lookfor寻找， 9、computerprogrammer电脑程序师， 10、inthefuture 在将来， 11、hundredsof成百上千的， 12、thesame…as与…一样， 13、overandoveragain反复， 14、getbored 无聊，
15、wakeup醒来/唤醒， 16、looklike 看起来像， 17、falldown倒下/落下 二、重要句子（语法） 、will+动词原形 将要做 2、fewer/more+可数名词复数更少/更多… 3、less/more+不可数名词 更少/更多 4、trytodosth. 尽力做某事 5、havetodosth 不得不做某事 6、agreewithsb. 同意某人的意见 7、such+名词（词组） 如此
8、playapartindoingsth 参与做某事 9、makesbdosth 让某人做某事 10、helpsbwithsth 帮助某人做某事 11、Therewillbe+主语+其他 将会有…. 12、Thereis/are+sb.+doingsth 有…正在做… 13、Itis +形容词+forsb+todosth 做某事对某人来说… 语法： whatwillthefuturebelike? citieswillbemorepolluted.Andtherewillbefewertrees. willpeopleusemoneyin100years?
《网页设计与制作》课程教学大纲 课程名称：网页设计与制作 学分及学时： 4 学分总学时72学时，理论36 学时 适用专业：网络工程 开课学期：第四学期 开课部门：计算机与互联网学院 先修课程：计算机文化基础计算机网络 考核要求：考试 使用教材及主要参考书： 向知礼主编：《网页设计与制作》航空工业出版社2017 年 杨松主编：《网页设计案例教程》航空工业出版社2015 年 一·课程性质和任务： 本课程全面地介绍网页制作技术的基本理论和实际应用。全书共 10 章，分为 3 大部分。前 5 章为第 1 部分，主要介绍网页制作的基本理论——HTML，同时穿插介绍Fireworks，Flash， Anfy 等软件在网页制作过程中的应用；第 6 章～第 8 章为第 2 部分，主要介绍网页 制作技术，包括CSS技术、客户端脚本技术(DHTML)以及 XML 技术；第9 章～第 10 章为第3 部分，主要介绍当前最流行的网页制作工具——Dreamweaver ，通过应用实践能够从实际 应用的角度进一步巩固所学知识。 课程内容不但包括各种网页制作技术的基础理论，而且强调网页制作的具体应用，使读者既能打下坚实的理论基础，又能掌握实际的操作技能。 二·课程教学目的与要求 以Dreamweaver 的使用为主线，介绍网页制作的相关技术。使学生理解网页制作的基本 概念和理论 ,掌握站点的建立和网页的设计 ,能用 HTML 语言修改网页 ;掌握网页制作和站点的基本 知识 ;掌握站点的创建和网页的编辑 ;掌握超链接、图像、 CSS样式的使用 ;掌握表格、框 架、表单、多媒体对象的使用 ; 理解行为、模板、库、 CSS布局的概念和使用 ;理解 HTML 语言、 网站的测试与的发布； 要求：教学过程中，须注重学生实践操作能力的培养，采取“面向实践、能力为先”的 教学思路，教学内容应结合当前WEB 技术的发展趋势，把握未来企业级WEB 页面开发的发 展方向，兼顾各行各业的需求变化，力争面向社会，服务于企业“互联网+”战略。
雅思口语范文 雅思口语考题基本上是五大原则：人，物，地点，事件，媒体。 T：在讲五大原则任何一个的时候，务必把这个原则与你联系在一起，开头的时候有个主题句，通过这句话引入下面的支持观点，这个主题句可以通过一到两句话来完成，但最好是对你有影响的。描述这个人---对你有影响;描述这个物----对你有意义;描述这个地点---对你有回忆等等。。。 S：支持观点，在这里要注意，我相信很多同学都会用观点来支持自己，但太过于白话文，大部分用例子来支撑，部分考生喜欢用For example，First , se condly, last but not the least来讲分论点，但这样给考官的感觉是在背作文，而不是真正的口语。在S这的观点一般是需要比较正式点的语言，每讲的一句话最好不少于5个单词以下，但最好不超过5句话。过渡词用什么好呢?最好用well , also , actually ,as a matter of fact , you know 等等词。 E：当然就是找到支持观点的例子，恰当的例子，但是字数不能过多，要简练。 以上就是这篇雅思口语万能模板的主要内容，大家可能会觉得这个模板过于简单，但是这是一个非常有用的模板，也是在论述一个话题的时候最有用的论述方法，尤其是对于雅思口语第二部分的答题很有帮助！下面小编就此模板给大家整理了16篇较为经典的范文，希望大家仔细斟酌，化为己用！ 经典范文 1.Describe a sport you are good at: Tennis I would like to talk about tennis, which is my best love among a ll the popular sports. Tennis is popular all over the world, especially
口语Topic问答模版（04考生严重参考） Q: Describe the best present/gift you have received Requirement: Who send it? When did you receive it? Detail information about the present. A: I have a Japanese friend. His name is Naoki Watanabe. I met him in Guangdong Sanyo company in 2001. We worked together there for 3 months. Last year, he visited me in golden week.He gave me the Walkman which is made in Sony in Japan. I use it for listening to English. It is small and delicate(exquisite ,fine),it is just as sa me as casette tapes. The color is light purple and it has a very clear voice. He told me that the price of walkman was 10,000 yen.(t en thousand yen,about90 U.S dollars) It helps me a lot for improving my English. I usually take it with me to listen to English after work . Q: In China, when will people send the present? A: In China, firstly, people send gifts on special holidays, such as in Spring festival, we got red bags with money, clothes from relat ive, which means that we got a next year's good luck again, in a friend’s birthday, we usually give a gift to him or her, the birthday gif t includes birthday card, flower, new clothes and decorations, secondl y when close friends will part, they will give some souvenir gifts each other for happy memories of their friendship. Q: Compare the gift which people have received 10 years ago to the present that people now are receiving, what's the difference between them? A: Ten years ago, the gifts people received were simpler and cheaper ,but nowadays they are pretty fine by appearance, higher quality, m ore beautiful packaging I think people will send flowers as gifts, T hey are beautiful and cool, especially flowers can be used in all a spects both good thing and bad thing. Q:Describe an interesting building What is the interesting building in you country/city? What is it located? What is used for? Explain why you think it is the most interesting? A:I am from Foshan. In my city, there is an interesting building wh ose name is Baihua plaza.It is located in the center of my city It has 65 storeies, and is the highest building in my city.It is use
人教版八年级英语上册Unit7知识点归纳整 理 Unit7illpeoplehaverobots? 短语归纳 onputer在电脑上2.onpaper在纸上3.aeup醒 livetodo200yearsold活动200岁5.freetie空闲时间indanger处于危险之中7.ontheearth在地球上 playapartinsth.参与某事9.inthefuture在未 0spacestation太空站11.puterprograer电脑编程员 loofor寻找13.hundredsof许多；成百上千 thesae…as…与……一样15.getbored感到厌烦的 overandoveragain多次；反复地17.falldon倒塌 ill+动词原形将要做…… feer/ore+可数名词复数更少/更多…… 0.less/ore+不可数名词更少/更多…… 1.havetodosth.不得不做某事 2.agreeithsb.同意某人的意见 3.such+名词如此…… playapartindoingsth.参与做某事 Thereillbe+主语+其他将会有…… Thereis/are+sb./sth.+doingsth.有……正在做某事
aesb.dosth.helpsb.ithsth.帮助某人做某事 trytodosth.尽力做某事 It’s+ad+forsb.todosth.对某人来说，做某事……的。 语法讲解 Boosillonlybeonputers,notonpaper.书将只在电脑里，而不是在纸上。 Thereillbeorepollution.将会有更多的污染。 ).Thereillbe+n=Thereis/aregoingtobe+n将会有…ThereisgoingtobeafootballatchthisFriday. ).pollution:污染；公害pollute：污染；弄脏polluted：受污染的 Everyoneshouldplayapartinsavingtheearth.每个人应该参与挽救地球。 Todaytherearealreadyrobotsoringinfactories.现在已经有机器人在工厂里工作了。 Therebesb.doingsth.有某人正在做…Thereisabirdsinginginthetree. Theyagreeitaytaehundredsofyears.他们同意这可能花费几百年的时间。 Ittaes+时间+todosth.某人花费时间区做某事。 Ittooehalfanhourtofinishyhoeor. agreetodosth.eagreetoeetuplaterandtalthingsover