This technology started in 1969 with the formation of DARPAnet and was the result of the U.S. Department of Defense (DoD) fear of losing computers ability to communicate during a nuclear war . Hence, the Internet was designed as a redundant network and as an unorganized system where each computer is an equal partner with all other peers, i.e., no centralization and no hierarchy. An additional feature of the DARPAnet, that made it very effective, was its protocol that enables exchange of data between computers with a different operating system. The transfer of the DARPAnet outside DoD started with DARPA desire to improve the communication among remotely located researchers at universities and other organizations throughout the U.S. This led to the development of the "Internet" protocol which superseded all other protocols available at that time.
Communication backbones, also know as servers network, was supported initially by the USA National Science Foundations (NSF) and was an indispensable contributor to the development of Internet. However, under the Acceptable Use Policy (AUP), NSF support was limited to non-commercial applications. Internet started flourishing at the moment when communication backbones became available from commercial carriers, especially after the creation of the World Wide Web (WWW) and Mosaic. WWW was developed by Tim Berners-Lee at CERN, the European Center for Particle Physics, to facilitate easy exchange of documents among researchers located in various corners of the world. It adopted the Hyper Text Markup Language (HTML), to be a subset of the Standard Generalized Markup Language (SGML), as an information vehicle independent of computer platforms and systems. It also defined the Hyper Text Transfer Protocol (HTTP) and the Universal Resource Locator (URL), so that a user can access documents distributed all over the world through hyperlinks (i.e., highlighted items in the text represent URL addresses and clicking with a mouse on the items activate the desired webpage). The user, however, had to read documents in line mode like telex, which is a rather cumbersome tool.
The most impact on making the Internet technology widely used was the release of the browser called Mosaic in 1993 by Mark Andersen at the National Center of Supercomputing Applications, University of Illinois (as an undergraduate project). Mosaic and its commercial derivatives, notably Netscape, retrieve documents and render them to a user-friendly graphic form. Most operations can be done by just "point and click" of a mouse, which made the WWW accessible to everyone. The Internet enables the communication of every imaginable form of data, including files, data, text, programs, pictures, video and sound. As an outgrowth from the original idea of equal computer peers, the spirit of the Network is: People helping people for "free" (using uncensored and low cost communication), enabling the formation of a "global village". Thus, the Internet has leveled the playing field such that, as long as someone has good ideas, it makes no difference whether he/she is a high powered lawyer on Wall Street or a young teenager in a small town overseas. A schematic view of the Internet connectivity between the user and the addressee is shown in Figure 1.
FIG 1: A schematic view of Internet communication between a user and an addressee.
The broader aspect of the Internet has been that its "free" nature allows rapid operation under difficult conditions, such as wars and civil conflicts without censorship. Further, the Internet totally changed many companies information handling policies since everybody has an easy access to many sources. This forced companies to form a new management hierarchy to deal with the open system of Internet. WWW and Internet are offering companies numerous capabilities in real-time: it allows to form and up-to-date electronic brochures describing the company, its experts, products and services. Some companies are starting to take advantage of the online benefits, e.g. parcel deliver companies are using interactive programs that show users where their packages are during its journey. This gives good service to customers while saving the providing companies in labor costs as well as reducing the need for slow and frustrating process of answering by phone.
Most business organizations, particularly in the USA, have now access to a high speed Internet communication connection and many public libraries/schools have terminals that are available for public use. At home, to connect to the Internet the user needs a computer with a modem, a phone line and a network service provider. The exponential growth of the Internet is providing easy access to an international network from every corner of the world. Once on the Internet, there are neither long distance charges nor international charges and the equipment, that is compatible with the Internet, is cost-effective because of the large number of users. Unlike conventional print media, there is no cost difference between black&white and color images and animation, movies, three-dimensional images and even virtual reality can be handled easily.
E-mail is quickly replacing many other communication tools, e.g. phone, fax and mail. This is increasingly becoming the preferred method of communication among technical individuals. Even though the "conversation" usually takes place in time-frame of minutes to hours, a person can check the message when convenient, the level of details is as desired, and the fact that the information can be used for further processing (e.g., write a paper, report, presentation or proposal) makes e-mail a very attractive tool.
Browsers to Webpages
Browsers are user-friendly human-to-machine interfaces to the WWW. There is a large number of browsers and the leading ones are: Mosaic, Navigator, and Explorer. Most operations on the browser can be done by just a mouse "point and click" and it accesses webpages that are provided to the user on remote computers and servers. Webpages are formed by companies, individuals and anyone who is seeking to offer a multimedia information. Webpages are now incorporating many Internet features, including FTP, e-mail, newsgroups, chat, and message boards. Also, webpages are providing online conferences, training, workshops, "Ask the expert" forums and in education -- virtual classrooms are being used. The response time of these tools varies from seconds and minutes to hours. Collaborative tools such as bulletin boards and newsgroups can be easily incorporated in the WWW services. Network security is an important issue and numerous means of securing communication as well as access control are now in use. Hence, a provider can offer simultaneously free services to the general public and exclusive services to its members. Interactive communication between a web server and a browser is provided by "mailto" and "form" tags of the language HTML. While this language has, at present, a limited capability it is expanding rapidly with the assistance of Java software options.
Technical communities are increasingly teaming to communicate various announcements, inquiries, etc. There are over 15,000 newsgroups, with their own distinct topic of discussion ranging from care of houseplants to techniques in mass spectroscopy. Usually, a specific question is posted and then answered by newsgroup readers within several hours.
Inter Relay Chat (IRC)
In a time-frame of seconds, this form of communication is used as a timely substitute to annual meetings. IRC is the Internet equivalent of the telephone party line, except that the communication is in text rather than voice. Dozens of people can communicate in a real-time forum once a time and channel are arranged. On any day, there may be over 10,000 IRC active channels, each with its own topic of discussion. To get onto IRC, the user needs in addition to an Internet connection also a special software [I-1] (Note: References to WWW Websites are identified with a I-#). The IRC software requires two parameters: an IRC server and an IRC channel. There are more that hundred servers from which to choose. The criteria to choose a server include, its geographic proximity to the user and its ease of access, i.e., not being overloaded with users. There are networks of servers like Efnet, Undernet, Dalnet, and Uppernet, but unfortunately, most servers are not connected to each other. Once an IRC server is selected, the channel to which to join needs to be identified and it is an IRC command allowing to view: the currently available channels; who are the individuals on the channel; and what is the topic of the discussion. A user can participate in several different channels at the same time. A channel can be defined in advanced and it requires an arrangement with the planned participants to assure the presence of others on the channel during active chat communication.
Voice conversation (real time) can now be made internationally at the price of a local call. With the recent introduction of standard freely accessible software from several computer companies, this technology is expected to become a dominated communication method that may change the phone as we know it. Multi-user interactive communication is increasingly being employed to form teleconferences employing mostly audio and text and increasingly expanding into video format. Video broadcasting are still at early stage of development. Improvement in quality and expansion of communication bandwidth are necessary before receiving wide acceptance by the general public.
Database searches and document retrieval search engines/agents
Powerful search engines and intelligent agents are now available for searching relevant information over the Internet. Search is still far from being perfect and the results may contain certain amount of noise, i.e., irrelevant information. For an efficient search, it is helpful if the word "NDT" is included somewhere in a text of the NDT webpage provider. To allow search of specific items, most search engines are now allowing the use of Boolean combinations (and/or). The search is an iterative process of browsing and information retrieval, where the search engines are attempting to provide ranking of search results and the best-match is shown first. Effective results are requiring a systematic, exhaustive and highly specialized search. Examples of the available search engines include: Yahoo, Alta Vista (full text), Lycos, Infoseek, Excite, as well as simultaneous search over multiple databases via Meta Search Engines (e.g., Savvy Search). Most search services are offering a simple input window, without any additional help information, whereas some advanced tools are available with hidden links .
NDT WEBPAGES IN THE USA
The NDT community in the USA has recognized the power of Internet and the World Wide Web. Having a webpage is now like having a business card, it provides identity description of the webpage owners. Numerous companies, organizations and individuals have formed webpages which are hyperlinked to other NDT websites. At the beginning of this year, ASNT joined the community of organizations having a website and the opening section of the ASNT webpage is shown in Figure 2 [I-2]. A user can review the various NDT services and products, access conference information, send e-mail messages to any of the society representatives and access numerous NDT websites of other organizations [I-3]. Also, the various committees of ASNT are now documenting their Minutes on webpages that are hyperlinked to the ASNT webpage. As an example one can view the Ultrasonic Personnel and Qualifications as well as the Ultrasonics Committees' webpage [I-4]. Other organizations that started using webpages to inform of conference announcements and agenda include Iowa State University. This year, for the first time the Review of Progress in Quantitative NDE was announced on a webpage ahead of the conference and details such as registration and others were available [I-5]. Various organizations are providing databases that are very useful to the NDT community. This include acoustic properties of various materials [I-6] as well as the properties of piezoelectric materials [I-7]. Some webpages cover specific methods such as acoustic emission [I-8]. Increasing, one can find individual papers posted as webpages as the example one can view a paper about Damage Identification and Health Monitoring on the website of the Los Alamos National Laboratory [I-9]. Other leading organizations that are providing detailed webpages include, NTIAC [I-10]. NASA NDE Working Group [I-11], and Iowa State University's Center for NDE [I-12]. The capability and the latest technology available from various organizations are also documented in webpages as for example one can review the JPL website [I-13], which has hyperlinks to various activities of the NDE & Advanced Actuators (AA) Lab.
NDT WORLD WIDE
Through an effort of NDT individuals from numerous countries, the NDT World Wide  was formed as a not-for-profit and voluntary hypermedia devoted to improve the communication among international NDT communities. Beside news and calendar events, NDT World Wide is hyperlinked to numerous NDT societies and research institutes (see Figure 3) [I-14]. NDT World Wide is intended to be a guide post, rather than a warehouse of NDT information, because of the organizers belief that information is best maintained and updated at the source locations. It is also recognized that the accessibility to the Internet varies from country to country. Therefore, NDT World Wide is assisting various NDT societies by preparing their webpages and providing them with a server to host their webpages until these societies form their own server. Among the various items that are posted on the NDT World Wide website are the final announcement of the 14th WCNDT, which will be held in India in December 1996 [I-15] and the first announcement of the 7the ERCNDT to be held in Denmark in May, 1998 [I-14]. Further, the 1st US/Japan Symposium on Progress in NDT was reported as a webpage as soon as the Symposium was over. It is interesting to note that many color pictures taken at the Symposium are included in the webpage [I-16]. There are also reports of the 8th Asian Pacific NDT conference [I-14] and the TC135 Meetings in Berlin [I-17 ]. Figure 3: NDT World Wide webpage.
International standardization is another promising area for the application of the Internet. The traditional process of international standardization based on mailed documents cannot cope any more with the rapid progress of technology and the globalization of the world market. The Central Secretariat of ISO (International Organization for Standardization) has now its own home page [I-18], ISO/TC135 (NDT) [I-17] and ICNDT [I-19] have webpages one set for the general public and another with exclusive access for the members (using a password). The speed of international standards development will be greatly improved by the positive use of the Internet.
NASA NDE WORKING GROUP (NNWG) WEBPAGE
In 1993, leading NDE representatives of all the NASA Centers agreed to form the NASA NDE Working Group (NNWG) to facilitate direct communication, collaboration and technical exchange across NASA and outreach to the technical societies, industry and the international community. To support the need for effective forum of communication, NNWG started Workshops that are held annually at different NASA Centers, hold periodic Teleconferences, issue the NNWG Newsletter (Y. Bar-Cohen, one of this paper coauthors, serves as the Editor) and maintain an NNWG webpage that is connected to the NASA Webpage [I-11]. The NNWG includes hyperlinks to the various issues of the Newsletter as well as to other NDT websites. As of October 1996, the Newsletter will involve from its current hardcopy version to an electronic form. The use of Internet among the NASA NDE community has grown from several users in 1994 to a full access availability to all the members of NNWG. The use of hardcopy mail and faxes has dropped significantly and most communication are done now in an electronic form, including announcements, submission of proposals, elections, etc.
Newsgroups are like electronic bulletin boards: a place to ask questions, to answer questions, or make announcements. The NDT Newsgroup (sci.techniques.testing.nondestructive) was created in July 1995, after it was proposed by M. Jones (one of this paper co-authors) in 1994 and being campaigned for and put to a vote (over 180 people from 16 countries voted in its favor). The Newsgroup has a mailing list, which is maintained electronically by the server and it allows subscribing individuals to participate in the Newgroup activity without any special access software. There is no cost associated with the subscription and an average of 2 to 3 messages per day are posted to this Newsgroup. The charter of the NDT Newsgroup does not allow advertisement and amazingly, with no moderator, there is a remarkably small number of advertisement instances. Announcements of opportunities, technical inquiries, availability of capabilities, call for papers, request for proposals, employment announcement, etc. are commonly posted on this electronic message board. For more information regarding the NDT Newsgroup charter, or how to access the archives of all past posts to the NDT Newsgroup, one can visit [I-20]. To subscribe to the NDT Newsgroup via e-mail, one needs to send a message to the address: nde-request@swrinde. nde.swri.edu with a command ``subscribe'' in the body of the email message. The subscription is done automatically and this method can also be used to remove the user name from the distribution by sending a message ``unsubscribe''. To send a message to all members of the mailing list the e-mail message needs to be addressed to: email@example.com (there is no need to test the address - it works).
NDT INTER RELAY CHAT (IRC) CHANNEL
M. Jones has an established weekly IRC Session to discuss NDT topics . The channel is called #NDT and it is using the Dalnet system as the server (irc.dal.net). The weekly topic is announced on the NDT Newsgroup (sci.techniques.testing.nondestructive) and it is held on Wednesdays at 12:00 noon (eastern U.S. time). The transcripts of previous #NDT Sessions are available at [I-20]. In case that an individual is interested in a topic but cannot attend an upcoming Session, a question or inquiry can be sent to firstname.lastname@example.org ahead of the meeting and the request is announced during the Session.
MATERIALS TESTING INTERNET RESOURCES (MTIR)
MTIR is a nonprofit corporation, that was created by M. Jones to promote the use of the Internet among the materials testing industry. MTIR consists of ten directors from five countries. This corporation was formed due to the belief that Internet is a valuable tool for engineers and scientists but no individual can keep up with the rapid improvement and growth of this technology. MTIR as a group combined its resources and knowledge to assist individuals and organizations to create material testing databases and other resources on the Internet. More information is available on the MTIR website [I-21].
NDE INTERNET IN EUROPE
|Europe is rapidly following the lead of the NDE community in the USA [I-22]. Generally, the internet users are still lagging behind as the UTonline Journal user statistics is showing [I-23]. The Journal examined the use of its server in the month of May 1996 and the results (see Figure 2), based on 25,000 downloaded files of the server showed that European used the server 66% less that the USA users. Over the European users, the German showed the largest number and this lead maybe explained by the speed of the Internet response (bandwidth) to the local users in Germany. UTonline was accessed strongly by the 15 Fraunhofer Institutes, who read 14% of the German Online files.|
FIGURE 4: Statistics of international Internet inquiries made to the UTonline Journal during the month of May, 1996.
Recently, the German Society for NDT (DGZfP) started a webpage service and has provided useful information that is translated to English [I-24]. German NDE manufacturers are still lagging to provide webpages because of their misconception that "our customers are not using Internet yet" or "I don't believe we can sell ultrasonic instruments via the Internet". As a contradiction of these statements, one can quote readers of the UTonline Journal who are sending feedback stating: "I just read this article and I am wondering who can deliver such a system? (Plant Manager)". In contrast to Germany, the U.K. has already made significant progress in introducing useful manufacturers and Institutes NDT webpages. The U.K. access of the UTonline server was ranked number two for the European users, however only limited reader feedback was recorded. The British Institute for NDT has recently formed a webpage and its address is [I-25]. Relatively to their size, Switzerland has a strong Internet user base, and as an example ETH Zurich is providing great NDT information on its webpage [I-26]. Further, even though they were ranked number 3 on the statistical ranking of visiting the UTonline and some French are NDT Newsgroup users, a search for French NDT webpages was unsuccessful.
The European Community offers a large information database, so-called CORDIS [I-27] through its Community Research and Development Information Service and it describes all the Research and Technological Developments (RTD) activity in Europe. At present, CORDIS offers 146,000 documents in 9 databases and they are offered for free access, via a the cumbersome Telnet tool. EC has already begun to provide search forms on their webpage and recently announced that soon all its databases will be accessible via WWW.
In Sept. 96, UTonline Journal (see Figure 5) will have its first Ultrasonic Online Workshop [I-28] and the subject will be Transducers. This is a new and unique Internet NDT experience and the theme of the workshop is an "Ask the Experts Forum". The forum (web page) feature papers of the panel of experts, as well as their photos. A Workshop-Library provides further information about transducers. The available resources, include: articles, abstracts, alphabetic ultrasonic information, and hyperlinks to other related websites. Also, an interactive Transducer Quiz (Q&A ) is provided and was produced using a Java script. The discussion procedure is based on an interactive form, where the readers fill in questions or contributions and the information is posted automatically at the Workshop "virtual site". The form supports attachments, e.g., documents, images, and URL addresses. Panel members take turn answering questions, where each is assigned one day of the week for the whole month of September. Questions are answered, within 1-2 days and the workshop is opened for feedback.
NEW ZEALAND NDT ASSOCIATION
Another active NDT organization on the Internet is the New Zealand NDT Association (NDTA) [I-29]. NDTA has one of the most unique and capable webpage layout and it is configured as a stack of folders (see Figure 6). Clicking on the tab of the folder items accesses various information resources, including employment opportunities, NDT information, etc.. While the NDTA webpage was formed only recently, the New Zealand NDT Association has a longer history -- it was formed in 1977.
THE CANADIAN SOCIETY FOR NDT A detailed information describing the history of the Canadian Society for NDT is available on their webpage [I-30]. The outline of this webpage is showing a list of hotlink options on the left and the details of the selected options are shown in a specially window on the right. The various services, products, society charter, scholarship opportunities, and events are all hyperlinked to this Internet address.
The use of the Internet capabilities, such as webpages, electronic databases, NDT teleconferences (audio/video), IRC and e-mail can enable the world NDE community to make a better use of its resources and respond faster to the rapidly changing needs. ASNT can take the lead in this global Internet networking that will link all the NDT experts throughout the world.
Major concerns that need to be addressed include copyright, security and universal access [I-31]. These issues are already being addressed by the Internet community and significantly more secured tools are now available to protect the provided Internet information.
ACKNOWLEDGEMENT The Jet Propulsion Laboratory, California Institute of Technology, portion of this paper was written under a contract with the National Aeronautic and Space Administration.