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AND WEB INFRASTRUCTURE

Database and World Wide Web Infrastructure for Application Development

Bruce C. Moore, Debra S. Wilhelm, Deborah K. Chen, Marvin B. Suther, and Anne M. DeMajistre

The Systems Services Group (TSS) of the Technical Services Depart- ment (TSD) provides an infrastructure of database servers, World Wide Web servers, and applications. This infrastructure supports the business, administrative, and technol- ogy needs of TSD and its staff and serves as a resource to other APL departments. By applying data administration and programming skills, Computer Systems Services staff have integrated the pieces—Web and application programming, Web administra- tion, and database administration—to provide customers with customized data systems and access to information residing in various . This article describes TSD’s database and infrastructure and highlights a number of applications developed by the Department in support of its customers. (Keywords: Application development, Database, Web.)

INTRODUCTION The Technical Services Department (TSD) provides number of cases, TSD has procured commercial soft- a diverse set of services to APL including engineering ware systems to help manage an expanding workload. and drafting design and fabrication, library services, These systems have often required customization either plant facilities maintenance and construction, and because they were designed to be customized by the publication services. To provide these services, the users or because there were interfaces or features that Department has established an infrastructure of com- needed to be added to the commercial product. puters, networks, databases, Web servers, and software The World Wide Web has brought about an unprec- applications. As is true elsewhere, information and data edented explosion of readily accessible information. Its system has become more important to all use has grown within TSD as it has in the rest of the aspects of the Laboratory’s business. This article focuses world. The availability of Web browsers on essentially on the application development environment in TSD, every APL desktop system has provided a “” including the database systems, Web servers, and soft- application interface for all users of any new custom ware tools in place to support the growing need for application. This makes distribution of an ap- custom applications that provide easy data access. In a plication across a group or a department much more

JOHNS HOPKINS APL TECHNICAL DIGEST, VOLUME 21,NUMBER 4 (2000)555 B. C. MOORE ET AL. straightforward. development is one DATABASE ENVIRONMENT area where TSD’s infrastructure support extends to We have used the Oracle RDBMS to support both other APL departments. We present a number of ex- applications developed within TSD and third-party ap- amples of custom intranet applications developed by plications used by the Department. Within TSD, Or- TSD’s Computer Systems Services Group (TSS) that acle installations are presently hosted on are making information available using the Web brows- platforms. Two Hewlett Packard HP-9000/810/D380 er as the interface. (HP-D380) currently support six production To support these customized applications, TSD Oracle databases. A third HP-D380 supports an addi- maintains a database environment with an infrastruc- tional seven preproduction test and development da- ture based on the Oracle RDBMS. As the Department tabases, and is available in whole or in parts to replace creates or procures new applications that use Oracle, either of the production in case of hardware the established hardware and software , as well as failure (Table 1). A RAID system and a tape backup staff resources, can be focused on efficiently supporting unit (DLT) provide storage, backup, and archiving for this single database environment. (See the glossary for each production system. A fourth system—an HP- terms used in this article.) C180—is a development that allows database

GLOSSARY CFML: for ColdFusion. OFA (Optimal Flexible Architecture): A set of CGI (Common Gateway Interface): A standard that configuration guidelines facilitating faster, more reliable allows programs to generate dynamic Web . CGI Oracle databases that are easier to maintain. scripts can be written in many languages including (but Oracle: RDBMS product from Oracle Corp. not limited to) “C”, , and . PDM (Product Data Management): System used to CMM (Computerized Maintenance Management): Any control, configure, and product-related informa- computerized system that helps manage data related to a tion supporting the product life cycle. company’s business. PeopleSoft: /server software for human resources, ColdFusion: Web from Allaire Corp. finance, materials management, distribution, and that allows for display of dynamic database-driven Web manufacturing in enterprise environments from pages. PeopleSoft, Inc. CSS (Cascading Style Sheet): A file that tells the Web PERL (Practical Extraction and Report Language): browser how to format the display of the HTML page. Shell script language designed as a tool for writing DataEase: RDBMS with a graphical from programs in the UNIX environment. Sapphire International, Inc. RAID (Redundant Array of Independent Disks): A DLT (Digital Linear Tape): High-performance, high- system of disks organized to provide redundancy and capacity streaming cartridge tape for use with DLT drives. fault tolerance. DMCS (Data Management and Control System): A RDBMS (Relational Database Management System): PDM product that served as the precursor to the current A type of database that stores data in the of Metaphase from SDRC. related tables, thereby allowing the data to be viewed FTP (): The mechanism for in several different ways. transferring files across the . SAFER (Safety and Fitness Electronic Records HTML ( Markup Language): Platform- System): System for monitoring intrastate and inter- independent language used to create Web . commercial traffic. JavaScript: A that enables Web au- SDRC (Structural Dynamics Research Corp.): thors to develop interactive Web sites. Vendor supplying the Metaphase PDM product and MAXIMO: Enterprise Asset Maintenance Software from DMCS. PSDI. Solaris: Sun Microsystems UNIX Metaphase: Enterprise-wide PDM package from SDRC. environment. Access: RDBMS product from Microsoft Corp. SQL (Structured Query Language): Standard lan- Enterprise Server: Enterprise-level Web server guage for commercial RDBMS. software from Netscape Corp. SQL*Net: Remote data access software product NFS (Network ): Distributed file system enabling client/server and server/server network that allows users to access files and directories located on database communications from Oracle Corp. remote computers and treat those files and directories as UNIX: Multi-user multitasking operating system if they were local. developed at Bell Labs. ODBC (Open DataBase Connectivity): A standard for VISUAL Manufacturing: Work management system accessing different database systems. from Lilly Software Associates.

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volume/directory names and Table 1. TSD Oracle servers. structures. The OFA imple- mentation also provides a mea- Dedicated sure of failure protection in that Memory Disk RAID Databases tape unit multiple copies of critical files Environment Server (MB) (GB) (GB) hosted (for backup) are written to different disks. Production tholos 1 512 19 38 pdm Yes Some performance improve- (HP-D380) vmfg ments are also achieved by en- appl73 suring that heavily accessed aplref files are on disks and controllers tholos 2 512 18 24 maxprod Yes of their own. To the extent that (HP-D380) maxloc the hardware has been avail- Preproduction iceberg 512 20 maxtest Yes able to allow the independent (HP-D380) maxtrial disk volumes to be created, maxdemo TSS has adhered to the OFA. maxdev The Oracle database infra- dvmfg structure was designed to sup- pvmfg port the requirements of multi- tsinfo ple projects within the TSD TSS raven 256 16 eval7 No area of responsibility. Figure 1 development (HP-C180) eval8 shows the growth in number and size of the TSD databases. Each colored band in the graph evaluations and version updates to be tried outside the represents an individual database instance, and the production and preproduction environments. thickness of the band indicates the relative size. The Computer Systems Services also maintains a Sun labels at the right show the project areas (some of SPARCserver 1000 as its production Web server. Al- which are described elsewhere in this article) supported though no Oracle databases are installed on this server, by the individual databases. database connectivity for the many Web documents Computer Systems Services uses a combination of that interact with Oracle is achieved by the installation operating system file backups, Oracle archive logging, and configuration of Oracle’s SQL*Net and client tools and logical database backups (database exports) as part on the SPARCserver. of an overall database backup and recovery plan. These TSD’s Oracle clients gain access to the databases via backups overlap in content to provide some redundancy Oracle client tools installed either on the user’s PC or in coverage for the range of failures that have been shared network file server, direct or NFS-mount considered. Database backup files are archived to tape connection to a UNIX database server, software appli- on a regular schedule and kept for future retrieval. The cation interface, ODBC, or Web interfaces. For PC clients, wherever possible, client-side SQL*Net is in- stalled on a network file server and 8000 shared out, which minimizes the 7000 Test administrative burden of having to visit individual client machines 6000 aplref whenever modifications or updates 5000 are made to the system. VISUAL With multiple databases on a sin- 4000 gle server, TSD needs a systematic 3000 Storage (MB) Storage approach to configuring them, both MAXIMO for ease of maintenance and perfor- 2000 mance. To this end, Oracle’s OFA1 1000 standard has been adopted, which appl73 PDM defines an approach to configuring 0 Oracle databases for low main- Q1Q2Q3 Q4 Q1Q2Q3 Q4 Q1Q2 Q3 Q4 Q1 Q2 1997 1998 1999 2000 tenance and high performance. Figure 1. Oracle database growth. Each horizontal “band” is an individual database; The standard includes specific file vertical height represents size. A break in a band indicates that the database was moved naming conventions as well as disk from one server to another.

JOHNS HOPKINS APL TECHNICAL DIGEST, VOLUME 21, NUMBER 4 (2000) 557 B. C. MOORE ET AL. most recent week’s worth of backup files is also kept on Today, the TSD production Web environment con- disk for quick access, even after being archived to tape. sists of the Netscape Enterprise Server software hosted Failures considered in designing the plan include acci- on a Sun UNIX workstation running the Solaris dental table deletion, corruption or loss of a database operating system with a ColdFusion Web Application file, or much more seriously, media failure such as a disk Server toolkit. ColdFusion has become our tool of crash. Recoveries from these failures require human in- choice for developing custom database-driven applica- tervention and make use of one or more of the different tions for the Web. TSD began using the toolkit in types of backup data. 1998 to increase productivity and has built many ap- plications using it (Table 2). Among other features, it provides easy connection to databases, allows valida- THE WEB tion of field entries in Web forms, and includes secu- TSD is involved with the Web in two principal rity features to provide some level of to areas: maintenance of a Web server environment to developed applications. support our presence on the APL intranet, and devel- Many of the Web pages developed by TSD, and in opment of Web-based applications both for TSD and particular TSS, access data in Oracle databases. Some other APL departments. of the major software applications that we support (e.g., Metaphase on which the PDM is built) have their own procedures for extracting and presenting the database Web Server data on the Web; for others, we had to write query and We became involved with the Web in early 1994 display routines. In earlier projects, the method used to when a curious staff member downloaded a National extract the data was a combination of PERL programs, Center for Supercomputing Applications (NCSA) UNIX shell scripts, and embedded SQL calls. Now, Web server and began experimenting with HTML and ColdFusion provides more straightforward connectivity CGI program development using PERL. One of those with TSD’s Oracle databases for those applications that experiments produced a dynamic report built by ex- require database access. tracting a formatted list of drawings from the PDM, a drawing release and electronic vault system. From this TSD-Developed Web Applications example, several staff members were quick to grasp the Table 2 lists some of the Web applications developed value of a as a universal client to view for our customers. Two of these applications are de- reports from TSD’s engineering databases. This type of scribed in more detail next to illustrate the function- dynamic reporting application was unusual in 1994, ality that has been implemented in these and similar when nearly all the published Web pages at APL con- applications. tained static information. In 1995 additional database-enabled applications were generated for customers in TSD and other APL Online Employment System Laboratory departments. For example, we provided Before the APL Online Employment System was tree and release information from the PDM, a proto- implemented in March 1997, people responded to ads type of the SAFER project that kept track of trucking in various and journals or at college cam- company safety records for a customer in the Strategic puses, usually with a letter of application and a resume. Systems Department, and a prototype of the APS APL would then either send the applicant an applica- (APL Procurement System) Requisition Status search tion or schedule an interview. page for the Business and Information Services With the TSD-developed online system, positions Department. open at APL could be viewed on the Laboratory’s An unanticipated side effect of these activities was external Web site.2 When visitors to the page found a the creation of a TSD throughout the position of interest (Fig. 2), they could request an Laboratory. The need for an official TSD Web presence application by mail or send e-mail directly to the re- was recognized in mid-1995, and the top-level HTML cruiter of the position along with their resume. The pages were completely redesigned to describe the De- positions were broken down by specific skill level (entry partment’s organization and services. Database report- level, experienced, support staff, or business/adminis- ing via Web pages has continued to be a major feature tration) and skill category (e.g., Aeronautics, Informa- requested by TSD customers. For example, in 1996 the tion Science, Digital Hardware Design, etc.). Electronic Services Group (TSE) Work Tracking Sys- We also created the scripts that provided an inter- tem was released, in 1997 the PDM reporting pages face to the Laboratory’s PeopleSoft System to break were revised and expanded, and earlier this year, time down the text files into the skill levels and categories card applications for MAXIMO and VISUAL Manu- mentioned previously. In the 3 years of its existence, facturing were created. APL averaged over 2500 unique visitors a month to its

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Table 2. Web applications developed by TSD’s Computer Systems Services. Additional Application Function Language(s) tool Database 4th & 5th Research and Enter/update/track papers and HTML, PERL Oracle Development Symposium* posters for APL-sponsored symposium Aegis Symposium* Register online HTML, PERL Standard e-mail messaging and text files APL Online Employment View all job openings at APL; HTML, PERL Standard e-mail System** submit resume; request job messaging and application text files APL Phonebook/Locator Display phone, location, and HTML, PERL Text files organizational information for employee APL Supervisory Feedback Allow supervisors to select APL CFML, HTML ColdFusion Microsoft Access Process staff for evaluation Computer-Based Training Download courses from a HTML, PERL Proprietary files System database of classes HFC-SDK Download Track and report licensed users HTML, PERL Text files for APL-generated software package Individual Country List all countries designated to HTML, PERL Text files Levels (ICTL) have terrorist threat possibilities IRAD Project Evaluations Enter/update/report project CFML, HTML ColdFusion Oracle evaluations for APL’s IR&D funds Laboratory Construction Check schedules, floor plans; list HTML FAQs; show live images of construction progress MAXIMO WyeTAS and Create and business- CFML, HTML ColdFusion Oracle Chargeback Applications necessary files from the TSD MAXIMO System NEAR Mathilde Encounter Simulate deep space activities HTML, PERL Text files and NEAR Earth Flyby* of NEAR spacecraft Patents Search System Load and search APL patents HTML, PERL Text files database PDM Queries Query the Metaphase PDM System CFML Oracle Plant Facilities Work Request Report status and funds expended CFML, HTML, ColdFusion DataEase (PFWR) System Reporting for plant facilities work CSS Property Management System List all surplus and pending HTML, PERL Text files (PEMS) transfer property R. E. Gibson Library Order Order books, periodicals, etc. HTML, PERL, Microsoft Access System** JavaScript Reproduction Copier Tracking Track APL copier readings and CFML, HTML ColdFusion Oracle maintenance contracts Reproduction Copy Requests Order copy services CFML, HTML, ColdFusion Standard e-mail JavaScript messaging SIGNAGE Generate room signs HTML, CSS Oracle Standard Naval Distribution List Look up naval installation HTML, PERL Oracle addresses around the world Stockroom Catalog System Search stockroom inventory HTML Text files Johns Hopkins APL Technical Manage work flow for Digest CFML, HTML, ColdFusion Oracle Digest production JavaScript TSD Help Desk** Enter/track customer-reported HTML, PERL, Oracle hardware and software problems JavaScript TSD Work Tracking System Search for work status of HTML, PERL Oracle customers’ tasks VISUAL Manufacturing Work Report status of work orders CFML ColdFusion Oracle Tracking System

Note: All applications are in operation, except those created for a special purpose/function* or when superceded**.

JOHNS HOPKINS APL TECHNICAL DIGEST, VOLUME 21, NUMBER 4 (2000) 559 B. C. MOORE ET AL. THIRD-PARTY APPLICATIONS In addition to supporting the Web applications already de- scribed, the infrastructure elements have been put in place to support three major commercial applica- tions used by TSD personnel to manage and monitor their work: Metaphase, MAXIMO, and VISU- AL Manufacturing. These multi- user (20–100) server-based systems all use an Oracle database for stor- ing application data and require networked access from the user’s . The Oracle databases reside on an HP UNIX server, which is shared with other supported applications. The executables for MAXIMO and Figure 2. APL Online Employment Application. VISUAL Manufacturing, as well as the SQL*Net Oracle database ac- cess software, are on dedicated NT external postings site and 1000 unique visitors a month servers. Each client workstation that runs these third- to its internal site. Visitors to the external site included party applications connects to the NT server by mapping people from the United States as well as 63 other a directory on the server as a local drive on the client. countries worldwide. Approximately 100 resumes a For Metaphase, the executables are installed on a single month were submitted via the Web interface. UNIX workstation. With more than 100 workstations spread over the APL campus accessing these applica- PDM Queries tions, this approach greatly reduces the effort required The combination of a Web browser, application for updates and modifications, as only the single copy on code, and database access offers the user a dynamic the server needs to be maintained. interface for retrieving data. Web pages are no longer In addition to providing this infrastructure, TSS has used as references of static data; they are live extrac- customized Metaphase and MAXIMO to work in the tions from online data. Many of the Web applications TSD environment. Both are large, enterprise-class ap- developed by TSD provide data dynamically by query- plications that require modification to suit the organi- ing a database at the time the page is requested. The zation using them. Screens, forms, reports, the under- user sees, via the Web application, the very latest in- lying database, and basic work flow elements have all formation that is available from online data storage. By been tailored to customer needs. VISUAL Manufactur- following a series of dynamically generated links in each ing has similar infrastructure requirements but was not successive page displayed, the user can drill down into customized by TSS. more detail in the live data. Another twist of this technique is the ability to build the pick lists from direct queries in real time. Metaphase An example of this from the PDM query page is TSD began using a PDM software system in April shown in Fig. 3. The list of projects presented to the 1994 to serve as an electronic vault and to control the user for selection is extracted from the database to configuration and release of formal APL engineering populate the pick list. Building the pick lists dynam- drawings. The system used DMCS 6.0 software from ically minimizes the amount of ongoing maintenance SDRC, which was customized by TSS personnel spe- for these pages in that the HTML code for the page cifically to handle the drawing release and configura- does not have to be manually changed when a new tion processes of the Laboratory. The Engineering, entry is required in the pick box. We use this tech- Design, and Fabrication groups in TSD incorporated nique wherever possible to provide Web pages that are the PDM into their standard practices for drawing always up to date while minimizing the maintenance release and change control, replacing the previous all- required. paper drawing book and configuration control system.

560 JOHNS HOPKINS APL TECHNICAL DIGEST, VOLUME 21, NUMBER 4 (2000) DATABASE AND WEB INFRASTRUCTURE

1. Entries in pick list are generated from database when page is displayed.

2. Clicking the “Find PDM Records” button executes query and brings up records matching the requested data.

3. Clicking on a “Drawing” link brings up a screen with detail on that specific drawing.

Figure 3. .

In September 1997, a product upgrade to the original the Metaphase application itself from a single HP UNIX DMCS software—now called Metaphase—was imple- platform and have users do a remote login and execute mented. The upgrade was neeeded because the original from the centralized server. This allows users the flex- DMCS software was no longer supported by SDRC and ibility to access the application from diverse computing would not run with newer versions of Oracle or the platforms without having to support a large variety of server hardware and software that was coming online. application installations. Users can also access informa- Again, this version required extensive customization for tion about a drawing in the system (e.g., release status, use in the TSD business environment. Since the prod- designer’s name) through Web applications that query uct was so different from its predecessor, none of the the underlying Oracle database directly. customization done previously was applicable. With its growing file storage needs, Metaphase con- The PDM handles the actual computer-aided engi- tinues to drive the technology being deployed within neering/computer-aided design (CAE/CAD) files that TSD. Computer Systems Services has added a RAID represent the design. These files, some of which are as storage system to enhance the system reliability and large as 650 MB, are “checked into” the PDM, which ensure that we can recover and restore files, even after then controls access and modifications to them and single disk failures. For data files that are “released” in provides a single electronic repository which can be the configuration system, and therefore will not backed up and archived as needed. change, we use CD-ROMs as the storage medium. A As already mentioned, Metaphase stores all of the CD-ROM jukebox that can hold 99 CDs has been data about the files it manages in an Oracle database added to allow data to be archived in permanent storage hosted on one of our UNIX servers. We elected to host and still be available for on-demand loading.

JOHNS HOPKINS APL TECHNICAL DIGEST, VOLUME 21, NUMBER 4 (2000) 561 B.C.MOOREETAL. MAXIMO and data collection modules that provide for easy entry of status data right on the shop floor. MAXIMO is a CMM system used by the Plant No major customization is planned for this applica- Engineering groups in TSD to plan and track their tion. Some interfaces to APL fiscal systems—specifical- work. This comprehensive software system handles ly the data warehouse—have been implemented, and work orders, inventory, preventive maintenance, Web-accessed reports are being generated. Its database equipment, locations, timekeeping, and other items and storage requirements are similar to MAXIMO, and associated with the maintenance of APL facilities. We other than database expansion from the continuing put the first piece, a preventive maintenance module, transactions associated with operations of the system, in pilot production in April 1998. The remainder of the no extraordinary storage growth is anticipated. system was put into production in October 1999. MAXIMO replaces several smaller computer applica- tions that were previously used to monitor and track FUTURE DIRECTIONS work. It extends these capabilities in a number of ways TSD’s Computing Systems Services is seeing an in- (e.g., by providing the preventive maintenance module creased demand for application development—partic- with its stored maintenance cycles). It also forms an ularly in the Web area—in support of customers in the integrated system that ties together applications that in Department and the rest of the Laboratory. The Web the previous system did not talk to one another and applications we are being asked to develop or support were labor-intensive to use and maintain. are becoming more complex as users see what can be MAXIMO is integrated with other data systems in done with this technology. To support this demand, we the Laboratory to minimize the amount of manual data are currently evaluating software configuration man- entry and reentry. To achieve this integration, TSD agement and Web site content management tools to created interfaces to APL’s spending authorization, data help manage these development efforts. In addition, warehouse, and timekeeping systems, and customized TSS is upgrading the TSD databases to Oracle 8 and screens and database fields within the MAXIMO ap- is restructuring the TSD Web environment with new plication itself. As with the customizations of the PDM server hardware and software. We expect the number discussed previously, these changes were needed to bet- of Web applications on the TSD servers to continue to ter fit the MAXIMO system into the way TSD and the grow and also anticipate that TSD staff will increas- Laboratory do business. ingly use the APL intranet to do their daily work. This will make the growth and continued support of the VISUAL Manufacturing production Oracle and Web server environments in TSD even more critical. A third major work management application, VI- SUAL Manufacturing, was put into production in REFERENCE AND NOTE March 1999. This manufacturing-oriented system, as its 1Millsap, C. V., The OFA Standard—Oracle 7 for Open Systems, Oracle System name implies, is used by TSD’s Engineering, Design, Performance Group Technical Paper (24 Sep 1995). 2This online employment system has since been supplanted. However, APL and Fabrication groups to help plan and track all of employment opportunities can still be accessed through the Laboratory’s their work. VISUAL Manufacturing also has bar code external home page at http://www.jhuapl.edu.

THE AUTHORS

BRUCE C. MOORE is a Section Supervisor in the Computer Systems Services Group of APL’s Technical Services Department. He received a B.E.E. from Rensselaer Polytechnic Institute in 1965 and an M.S.E.E. from The Johns Hopkins University in 1978. Before joining APL, he worked as an engineer for RCA Astro Electronics Division. He joined APL’s Space Department in 1975 doing hardware design of command, telemetry, and data handling systems for the TIP-2, TRANSAT, AMPTE, GEOSAT, and Polar Bear satellites. In 1986, he transferred to TSD and provided engineering support for CAE/CAD, packaging design, and fabrication of hardware for MSX and other programs. Since 1993, he has worked in the areas of , Web application development, and database design and administration. His e-mail address is [email protected].

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DEBRA S. WILHELM received a B.S. degree in from the University of Maryland in 1985 and an M.S. degree in technical management from The Johns Hopkins University in 1994. She is a Senior Professional Staff member of the Computer Systems Services Group of the Technical Services Department. She began her career at APL in 1995 with responsibility for implementing and supporting the Metaphase Product Data Management System. Ms. Wilhelm has also been involved with various Web-based application developments supporting both TSD and other APL departments. Prior to joining APL she worked in industry as both a technical manager and developer, primarily on real-time software simulation projects. Her e-mail address is [email protected].

DEBORAH K. CHEN is a Senior Professional Staff member of APL’s Computer Systems Services Group of the Technical Services Department. She received a B.S. in pharmacy from the Philadelphia College of Pharmacy and Science in 1983 and a B.S. in computer science from the University of Maryland in 1985. Prior to joining APL in 1996, she worked in private industry in the area of and development for real-time simulation systems. Her work at APL has been primarily involved with database-related software development efforts including the MAXIMO Project as well as responsibility for Oracle database administration and supporting software. Her e-mail address is [email protected].

MARVIN B. SUTHER is a member of APL’s Senior Professional Staff in the Computer Systems Services Group of the Technical Services Department. He has a B.S. degree in computer science from Kansas State University. Prior to coming to APL in 1983, he worked for C&P Telephone of Maryland, where he helped write software associated with the breakup of AT&T and the transfer of services to the seven regional Bell companies. At APL, Mr. Suther’s activities have included development of interfaces for engineering applications, timecard collection and reporting software for the TSD internal network, and Web page development for several departments including TSD, Human Resources and Services, and Space. His e-mail address is [email protected].

ANNE M. DeMAJISTRE received a B.A. degree from The City University of New York in 1979 and an M.S. degree from the University of Maryland in 1986, both in computer science. Her master’s research investigated artificial intelli- gence methods for pattern recognition and cooperative query answering. Before joining the Computer Systems Services Group of the Technical Services Department in 1997, she worked for Hughes STX Corporation at the NASA Goddard Space Flight Center. She has broad experience in with a concentration in systems, and has co-authored several articles under her maiden name, Anne Litcher. Ms. DeMajistre has spent the last several years developing information retrieval applications for the Web. Her e-mail address is [email protected].

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