WebApplications’analysisandDesignbasedon.doc

精品论文web applications analysis and design based oncomputer mediated communication1wang wenxiu, luo siweidepartment of computer science and technology beijing jiaotong university beijing（100044）e-mail: nju_, abstractthis paper introduces and analyzes the web applications based on the point of view of computermediated communication through theories and examples. for instance, the web based ict technology was analyzed through the medias law which is a general guide for communication. meanwhile, by discussing the communication history, i try to make the computer scientists aware that they are in the process of “communication revolution” of human being and as the protagonists they should have a high point of view of the whole society when doing research or design, favoring the positive ones and avoid the negative ones as possible as they could. from this article we can see that web applications based on computer mediated communication has already changed or impacted the whole society. however, as the degree of development of internet, the computer mediated communication revolution is only really at the beginning.keywords: communication; cmc; virtual community1intr oduct i on nowadays, no matter what job you do, when you wake up or get into the office the first thing you do is to switch on your computer and connect to the internet. then you check your mailbox and see some news from the website instead of newspapers. later, its time for the videoconference from where you boss assigns your work today. after the conference, you open your message, ask for the files that your need from your colleagues. during the lunch, you remember you need to shop for a new book, so you book them on ebay.when you finish the work day going home, you reflect upon how internet and it tools have become an indispensable part of your life: you could not imagine living and working without it. and to remember that a few years ago you wrote academic papers in that big library without knowing the existence of internet.you cant deny that the internet and cmc (computer mediated communication) tools are the newest and most powerful communication technologies. and they conquer the whole world at an unprecedented pace. when we get into the internet era, people communicate and share information by “use hands without even open the mouth”. people influence each other just via the keyboard and mouse. they have changed our life style unconsciously: the way we cooperate, the way we learn, the way we buy, the way we service the clients, the way of our professional activities, and so on.through the history, we can see that its not the first time a new communication technology has arisen and caused some changes in a society. from the original face-to-face communication, people have gone through from writing to press print, from the telegraph to the telephone, from tv sets to personal computers. still no doubt, internet and cmc tools are the strongest impact and most powerful ones so far. they can be considered as a milestone in this long history process. another thing need to be paid attention is that most of the different ways of communication are coexist. the pre-existed technologies will not vanish because of the emergence of new technology.from this perspective, all the computer scientists are among the protagonists of the1 support by special fund for fast sharing of science paper in net era by cstd (20070004053).- 11 -“communication revolution”. this article aims at promoting a reflection on the impact of communication means, so as to enable computer scientists to aware of the opportunities, understand, predict and steer their effects, favoring the positive ones and trying to avoid the negative ones when inventing or designing cmc applications.2comm unication theor y2.1 med i a ted co mm u n i cati on communication can be defined as an exchange of information that makes sense, i.e. an exchange of message. human communication takes place under the mediation of some kind of technology: it can be mediated through the basic form of communication technology writing or through invented media, such as radio, television, chat, videoconference and so on.the following is a feature map of mediated communication. (it has to be saying that face-to-face conversation is the only immediate setting of communication.) even there is not a perfect communication way, but still you can make your best choice according to needs.table 1: a map for mediated communicationfeaturespcvisainsevrevroken/o-presibilityudibilitantaneianesceniewabilievisab wriencetytycetyilityttensettingftfs+-conversation+telephone conversations-+-+lettersw-+e-mailw-?-+chat,messengersw-+video-conferences-+-+websites/blogsw-+wikisw-+(+ means positive effect; - means negative effect; ? means dependence with instance)2.2 di f f u s i o n t h eori es when a new technology comes into the society, it can not be accepted immediately. in fact, there is an adoption process and many factors influence the adoption, such as social factors, economic factors, even legal and political factor and so on. everett m.rogerss scholarly and scientific diffusion of innovations (1995), which has become the standard textbook and reference on diffusion studies, has explained spread of innovations within a social system.everett m.rogers defines an innovation as “an idea, practice or object that is perceived as new by an individual or other unit of adoption”(roger 1995: 11), and diffusion as “the process by which an innovation is communicated through certain channels over time among the members of a social system. it is special type of communication, in that the messages are concerned with new ideas” (roger 1995: 5).2.2.1innovati o n d eci si on process in general, when someone is confronted with a new technology, he/she goes through an adoption decision process in which he/she gathers information, tests the technology, and then considers whether it offers a sufficient improvement to warrant the investment of time and energy that is required to add it to his/her repertoire of skills (rogers, 1995). the computer sciences being urged to integrate technology in cmc tools face a similar situation.since early in this century, various new computer technologies have been adopted and integrated into the way of communication with varying degrees of success. rogers presented a model of the innovation decision process which contains five stages in the process that leads people to the decision of adopting an innovation:(1) knowledge stage: the “adoption unit” become aware of the existence and the working of a new technology;(2) persuasion stage: the individual forms a favorable attitude towards the innovation; (3) decision stage: the individual decides to adopt or reject the innovation;(4) implementation stage: the individual puts the innovation into use;(5) confirmation stage: the individual seeks reinforcement of the decision already made and seeks to avoid a state of dissonance or reduce it. (rogers 1995)2.2.2perceive d a ttrib utes usually what make an innovation success or much more acceptable by people? of course, the technology itself is not the only reason. in order to facilitate potential adopters of a new technology to overcome their uncertainties, some key characteristics of the innovation must be perceived by them. in fact, rogers says that 5 different characteristics of innovations explain most of the adoption rate. he describes each of these attributes.(1) relative advantage of an innovation. how much better is an innovation than the idea that came before it? economic profitability: does this innovation increase my financial benefits or decrease my costs? low initial cost: is this innovation cheaper to purchase? decrease in discomfort: does this innovation make my life easier? social prestige: will people think better of me when i have this innovation? savings in time and effort: is this innovation easier and quicker to use? immediacy of the reward: does the innovation benefit me now, or do i have to wait for the benefit to come about?(2) compatibility of an innovation. is the innovation compatible with existing practices and values?(3) complexity of an innovation. an innovation should not overly complex. rogers gives the example of the home computer. during the late 1970s when home computers first became available, they were used primarily by people who played with technological gadgets as a hobby. many were engineers or others who had extensive experience with mainframe or minicomputers. for these early adopters, home computers were not complex. when less technically proficient users began to buy home computers in the early 1980s, studies found that their level of frustration during the initial period was extremely high. the computer hardware, software, and jargon were simply too complex for most people to understand. so, the rate of adoption of computers was quite slow. however, the rate of adoption soared as computers became easier to use and understand.(4) trialability of an innovation. trialability is the degree to which an innovation can be experimented with on a limited basis.(5) observability of an innovation. observability is the degree to which the results of an innovation are visible to others.in 1997, fidler added two more attributes as following to rogers perceived attributes. (6) reliability of an innovation. the innovation must be perceived as reliable.(7) familiarity of an innovation. familiarity is the degree to which an innovation is perceived as familiarly linked to earlier or existing technologies, avoiding sudden breaks with the past. it is the case, for instance, cellular telephones are strictly linked with wired telephones; the function for the e-bag of shopping online is quite the same to the bag we used in daily life; and so on.in addition to the innovations attributes that need to be perceived, there must be other accelerators in order for an innovation to spread, such as an opportunity or other motivating social, political or economic reasons.these perceived attributes above are the more consideration for the computer sciences that is going to invent or improve the innovation of application used for communication.3com puter mediated comm unicat i on 3.1 cmc f e a t u res cmcshoredforcomputermediatedcommunicationisusuallyintendedas people-to-people interaction through a computer with the help of internet or intranet. actually the origin of cmc can be traced back to the origin of internet itself, since technically cmc is nothing but a decentralized from of electronic communication. recently the growth of internet has moved the attention of some computer science such as hci (human computer interaction) studies from the isolated computer application design to communications taking place between human beings by means of a computer. “hci studies became less concerned with the design of interfaces intended to enhance cognitive compatibility between isolated pcs and equally isolated individual users and began to worry about improving the connectivity among communities of humans and computers” (mantovani 2001). this means that computers are not only a terminal of human operation as a tool but also a connecting tool for human communication, as other real communication mediums.before we talked about the features of cmc, lets review some tools of cmc. e-mail ：as the most used cmc tool, it is a store-and-forward method of writing, sending, receiving and saving messages over electronic communication systems (wikipedia).e-mail provides a way to exchange information between two or more people with no set-up costs and that is generally far less expensive than physical meetings or phone calls. the same time, e-mail allows asynchrony - each participant to decide when and how much time they will spend dealing with any associated information. forum: it is an online discussion site. from a technological standpoint, forum or boards are web applications managing user-generated content. forums consist of a group of contributors who usually must registered with the system, becoming known as members. the members submit topics for discussion (known as threads) and communicate with each other using publicly visible messages (referred to as posts) or private messaging. online chat: its a synchronous cmc tool that allows people share or exchange text-based information either in private or in public, and either with the form of one-to-one or in, using tools such as instant messengers, talkers and qq. not as the asynchronous feature of e-mail and forum, the chat participants are meant to communicate synchronously and delays are ascribed to technical problems (lags) and typing speed. the messages are listed chronologically one after the other together with the name of the author. videoconferences: it is a set of interactive telecommunication technologies which allow two or more locations to interact via two-way video and audio transmissions simultaneously. videoconferencing is less anonymous since videoconferencing is mostly conducted in known groups such as virtual seminars or spatially distant teams (wikipedia). and videoconferences utilize much more bandwidth than textbased forms of cmc. thanks for the advantages that videoconference brings to the public, many industries have been faciliated by it, such as education industry, medicine and health industry, business industry and so on. file sharing: file sharing refers to the providing and receiving of digital files of different types over a network, usually following the peer-to-peer (p2p) model,i.e. “a type of computer networks uses diverse connectivity between participants in a network and the cumulative bandwidth of network participants rather than conventional centralized resources where a relatively low number of servers provide the core value to a service or application.” , where the files are stored on and served by personal computers of the users. most people who engage in file sharing on the internet both provide (upload) files and receive (download) files (wikipedia). website: together with e-mail, webiste is no doubt the most popular cmc tool, through which many service are offered to people, such as news, academic journals, games, web-based e-mail, real-time stock market data, electornic commerce, message boards, social networking, and so on.from several examples of cmc tool above, we can see that cmc relies extraordinary on the technology of internet. therefore, it inherits from the internet its potential as well as limits. obviously one important aspect concerning cmc with internet is its bandwidth. weinberger and mandl (2003) propose to classify cmc media according to the bandwidth: thus, they distinguish low-bandwidth form high-bandwidth cmc media. low-bandwidth media are mainly text-based, while high-bandwidth media encode information through other channels such as picture, video, sound, flash, and so on.cmc tools can also be classified by other relevant parameters as well. concerning time, they can be divided into synchronous way and asynchronous way. for instance, chat and videoconference and been seen as synchronous even there might be some delay due to the technology of transmission, and on the other hand forum is a typical asynchronous communication way.another interesting feature of cmc is anonymity allowed. according to the media used, participants may remain anonymous or assume different identities, by using nicknames or fake address; on the other hand, however, participants may also reveal some informationunwillingly, for instance their server address by means of log files (weinberger and mandl2003).other features such as co-presence, instantaneity, evanescence, revieability, revisbility which is presented in table 1 could be the guide of classification of cmc tools.3.2 med i a s l a wh.m. mcluhan had propose laws of media which are intended to provide a ready means of identifying the properties of and actions exerted upon themselves by technologies and media and artifacts. they apply to all human artifacts, whether hardware or software, whether bulldozers or buttons, or poetic styles or philosophical systems (h.m. mcluhan 1992). thus, cmc tools as a kind of media for communication, they should also be corresponding to laws of media. the laws are framed as questions by four parts, and lets talk about them with an example of cmc tool ict (information and communications technology): enhance: what does the artifact enhance or intensity or make possible or accelerate?for instance, the following is the enhancement which ict brings to the field of education. first of all, ict reduces the cost of distance education. from the figure x, it is obviousthat for large number of students, ict makes total cost lower than traditional method. in the ict situation, once the asset is prepared, it can afford much larger number of students than traditional method, and there is no additional cost on printed learning materials, equipments, classrooms and so on.figure 4. comparison of ict and traditional method in the cost of educationsecondly, with the development of ict, pc and internet are popularized. lots of services and contents are avai