Mark R. Fernandez,
Jim Miller,
Jeffrey L. Becklehimer, and
Bill Maloy
Abstract
Since being introduced to the World Wide Web (WWW), the Naval Research Laboratory (NRL) at Stennis Space Center, MS has exploited the capabilities of hypermedia and greatly expanded its use locally, particularly in scientific applications development, software documentation, data sharing, and briefing support.
This paper details the use of hypermedia in these four areas and the issues and problems solved by its use. The documentation in hypermedia of custom software libraries such as the Ocean Tool Kit (OTK) and the Tactical Oceanography Simulation Laboratory Library (TOSLlib) is discussed. Furthermore, the benefits gained by hypermedia documentation on programmer productivity and increased software reuse are reviewed.
The ability to layer on-line Help functions of software applications to meet the needs of both novice and experienced users has significantly increased its usefulness. In addition, the creation of documentation which is clearly superior to conventional static help text or printed materials and which is also less burdensome is presented.
Also, reported is management's acceptance of having their needs for current, up-to-date presentation and briefing support now being supplied on-line in the form of Mosaic project specific home pages and hyperlinks.
Finally, the benefits of sharing scientific data via web browsers and gateways are discussed in terms of a homogeneous interface to heterogeneous database management systems.
Keywords: applications, documentation, research, government, U.S. Navy
Introduction
While a number of members of the staff were familiar with the World Wide Web (WWW) , it was at first considered to be only a convenient way to find a variety of things on the Internet. But as the capabilities of hypermedia became clearer, it quickly became apparent that these capabilities could be used to support some of the major scientific applications development efforts that were in progress at the Naval Research Laboratory at the Stennis Space Center (NRL-SSC) . This effort expanded into the use of hypermedia in scientific applications development, software documentation, data sharing, and most recently, briefing support. We basically rediscovered the genesis of the World Wide Web which has been described as a "small 'home-brew' personal hypertext system used for keeping track of personal informations on a distributed project." [1] Below is detailed the use of the World Wide Web and hypermedia for "keeping track of" programmer progress on applications development, for "keeping track of" on-line help at several levels of detail ranging from novice to expert user, for "keeping track of" useful data without being concerned about data base management details, and for "keeping track of" what your management is telling customers about your projects and what you would like to have your management tell.
Scientific Applications and Their Development
At the Naval Research Laboratory, numerous scientific research efforts are under way. Two of the major efforts are the the Tactical Oceanography Simulation Laboratory (TOSL) with TOSLlib its supporting custom software library, and the Ocean Tool Kit (OTK) , which is a collection of software products tailored for use by NRL's ocean modeling community.
The Tactical Oceanography Simulation Laboratory is a series of environmental acoustic and non-acoustic algorithms, software and visual techniques which provide the tools for exact recreations of oceanographic, bathymetric, geophysical, acoustic, non-acoustic, and sensor system characteristics. These recreations, through simulations, are applied to issues such as sensor system development, production, acquisition, and performance analysis. Numerous graphics languages and software packages are combined to provide a state-of-the-art graphics capability in an "X" Motif environment.
The Ocean Tool Kit (OTK) is a collection of public domain and locally developed software products which provide a "toolkit" upon which larger, more ambitious projects can be constructed. The purpose of OTK is to enhance overall productivity by providing a common set of tools which allows NRL ocean modelers to spend more time on the science of ocean modeling and less on data bases, graphics preparation, etc.
Both of these projects, like many projects, required and have employed numerous developers, sometimes separated by great distances, and often working uncommon hours in different time zones. Fortunately, both of these projects are such that they could be logically divided into major components which could be assigned to individual developers. Communication and coordination, as in any project such treated, then become of paramount importance. Aiding in accomplishing this has always been the creation of conventions, standards, and quasi data dictionaries. By placing these items in hypermedia, the developers continually have up-to-date information.
Hyperlinks to Tables of Contents, Getting Started, What's New, etc. relieve the creator of such documentation from also being the disseminator of the documentation. All developers can access the information at their convenience without burdening the author of the information at what experience has shown is always the most inconvenient time. The random access nature provided by hyperlinks to other documents and to other locations within a document allow the "reader" to jump immediately to the needed information. This has provided quick access for the experienced user and a step-by-step logical interface for the novice. Furthermore, the creator of the hypermedia is relieved of the distribution burden of assuring that the developers are given the latest-and-greatest version of documentation, and the accompanying need to destroy the out-of-date material disappears. An example of hypermedia documentation is the OTK Home Page which maintains an up-to-date list of required public domain software tools, a list of custom in-house developed tools, and instructions on how to get started.
Another similar example is the TOSLlib documentation. Most of the TOSL Tools are heavily object-oriented, and as such are written in C++. The reader is presented initially with a Table of Contents to the library with a brief description of the routine or class. This is the first level of detail provided. An entry in the Table of Contents, like those on the OTK Home Page, is actually an internal hyperlink to elsewhere in the document. At that link, a more detailed description is provided and the parameter definitions are given. For simple routines, these descriptions and the parameters might be sufficient. Since the C++/Motif environment is being used, callback routines can be exploited and, if applicable, are included. The user can cut-and-paste this information easily from the document and edit as necessary. This level of detail may be sufficient for some routines. But for C++ classes, additional details may be required. Although C++ prototypes can be found in the header files, they are provided for convenience as are member function declarations. Finally, the Other Information section gives the latest version number and date, and hyperlinks to the actual code and header files. The actual code is provided to assist developers when they need insight into how certain aspects of routines are performed in the event they may need a similar functionality.
As one can surmise, this level of documentation is intended for use by the development staff. Whether the documentation concerns a toolkit of completed routines or a library of C++ classes, the ease of creation, maintenance, and use of the hypermedia documentation has increased productivity through the reuse of existing software, and through both the volume and quality of the accompanying documentation. Such increased software reuse due to ease of access further reduces programming time, debugging time, and overall development costs.
Software Documentation and Online Help
One step removed from the software development is its use. Like the development stage discussed above, on-line help of applications software in the form of hypermedia has greatly increased not only the volume but also the quality of the help provided to the user. In the case of software development as discussed above, the "user" was another developer wanting to exploit existing software, library routines, etc. created by associate developers. In this case, the "user" is one who wants to exercise the finished software product. In the case of TOSL, all of the independently created tools and modules are in compliance with the Motif standard. Although Motif has been around for several years, it is foolish to assume that all users will be fluent in its use. Thus, a need existed to provide on-line help for the novice Motif user. Furthermore, this level of help does not lend itself to reuse if it is written in such manner as to address the use of only the Motif widgets present in each specific application. Additionally, motivating programmers to produce "ground up" on-line help for each application is difficult. Furthermore, the exact use of a specific widget for a very specific scientific function would be too detailed to expect the experienced Motif user to endure, or to expect the applications programmer to provide for each application. In essence, the need existed to separate the use of a general widget from the meaning of a specific widget. Using hypermedia, this was accomplished. Its success has demonstrated to the programmers that on-line help does not need to be too burdensome, that they can address help at an appropriately high level, and that help offered will be usable. Once help is being used and appreciated, support and maintenance for keeping it current is easier to obtain. Additionally, the ability to to perform basic on-line formatting such as bold, italics, and preformatted in a platform independent manner has greatly increased the readability and effectiveness of the documentation.
As detailed above, the on-line help offered by all TOSL tools is provided in several levels. The initial window presented when the Help button is pressed depicts in a bold bulletted format Basic Features, Information About <ThisTool>, and Advanced Information. The Basic Features section is common to all TOSL Tools and is simply a statement containing hyperlinks to a common page describing Motif widgets in general terms and their use and basic operation. Most of the text at that Uniform Resource Locator (URL) was derived from the Motif User's Guide. [2] Since it appears as a URL referenced by all TOSL Tool Help functions, maintenance is minimized and developer effort can be concentrated on creating the Information About <ThisTool> section. The brevity of the Basic Features section is such that an experienced user can quickly navigate to the advanced discussion with little effort. Conversely, the novice is encourage to follow the Basic Feature link. Upon returning, the user will find that the Information About <ThisTool> section details the specific functions of the Motif widgets by application name. For example, "The X-Axis slider widget controls the ...". The actual operation of a slider widget is not discussed here; only the x-axis aspects of the application. The applications programmer who coded each specific widget is the best qualified to discuss the actions of that specific widget and is responsible for the detailed documentation appropriate for that application. Freeing the programmer from the elementary details of general widget description has resulted in more documentation of higher quality.
Finally, the Advanced Information refers the reader to scientific papers and journal articles about the specific subject, or to scientists qualified to answer questions related to the model or the phenomenon being modeled. If a particular scientist has a URL reference, that is also provided.
Data Sharing
Once a user has a functional piece of software, data is often required for processing. In scientific research such as that performed at NRL, the second question posed after an affirmative is given to the "Do you have a certain type of data?" question, is "What is its format?". Although hypermedia cannot address common data formats directly, it has an extreme impact upon such a simple question. Often the format question yields an answer which involves a specific network protocol, on a specific machine, with a specific operating system, running a specific database management system, requiring cumbersome access privileges, etc. By using a URL off of a home page, for example, the data provider can free the user from being concerned about almost all of these factors, and at the same time, free the database administrator from extraneous user support when database specific details change which do not effect the output format for the end user. The standard interface provided by the World Wide Web and its browsers such as NCSA's Mosaic has eliminated about all of the detailed information concerning different platforms, systems, etc. which historically have needed to be exchanged before any real exchange of data, ideas, or development could take place.
An example of this is the gateway provided by NRL Code 7430 , the Seafloor Sciences Branch, known as the ETOPO5 Data Server. This type of data has been used by NRL to its own personnel and outside customers routinely, but until the WWW and Mosaic, the user was required to keep abreast of the currently used database system and its nuances. Since the creation of the ETOPO5 Data Server as an experimental data server, the hardware support system, the operating system and the extraction software have undergone major changes and revisions without effecting the customer or even informing the user community. In fact, even the IP address of the server has changed without effecting users; this is due to the fact that the which are dynamically resolved into IP addresses. A change in the IP address of a machine name can be done at the local level by the data provider as the database management system evolves without adversely effecting customer service. By maintaining a URL, the customer has a pointer to the resources needed without having to deal with any of the technology required to support those resources.
Management and Briefing Support
It is often required that the completed milestones or projects be presented to the sponsors by the technical management staff in the form of a brief. Although not the focus of the brief, the hypermedia programmer documentation, the user on-line help, and data gateway play an important role in the preparation of the brief because they are presented in a uniform manner due to the common hypermedia linkage. Furthermore, assembling all the sources of materials to support such a brief can involve several computer systems with differing operating systems, presentation packages, etc. The use of hypermedia with its rich offering of available supported AV (audio/visual) formats has made presentation creation easier. By establishing a "home page" for a brief, contributors can add their respective URLs to the page asynchronously, and management has access to the best available at the presentation time. As projects evolve, and supplemental briefs are required, the home pages evolve also and become more populated with the advancement of the projects. Examples of this include the Modular Ocean Data Assimilation System (MODAS) home page and the home page of Bill Maloy , one of the authors. The MODAS is a set of programs designed to incorporate real time remotely sensed, in situ, and synthetic data into three dimensional temperature and salinity fields. The timely nature of this data is apparent and the usefullness of maintaining a home page with timely examples is obvious. Similarly, Mr. Maloy maintains a home page including a movie archive containing some of the existing and ongoing research project results with hyperlinks to other project documents.
On a similar but slightly different subject, preparing for research proposals and conference papers can be made easier using the World Wide Web. Recently, NCSA's Mosaic was used to access distributed hypermedia documentation on two time critical projects. The first was to obtain sources and determine the availability of climate change data for NRL's input into a Strategic Environmental Research and Development Program (SERDP) meeting. Data sources, working groups, and key points of contact were all identified in less than an hour. Additionally, the information was up to the minute since the master list receives frequent updates. The other project was a joint proposal effort for NASA's Ocean Color Program. The researcher was informed of the possible project on a Monday and given some sketchy details on Tuesday. After a quick Mosaic session the researcher had a documentation package together with links to other documents and information for further reference, all in time for a Wednesday afternoon conference call.
The primary advantages of using the distributed hypermedia have been identified as the ability to quickly (in a matter of minutes) find the specific information one needs, be able to review it on the screen so that only pertinent information and graphics are accessed, and finally the ability to download the information, software and documentation directly to one's local computer.
Summary and Conclusions
A summary of the recent experiences and uses of distributed hypermedia at NRL-SSC has been presented. Furthermore, the advantages of using hypermedia programmer level and user on-line documentation, of data sharing through the homogeneous hypermedia interface to heterogeneous database management systems, and of supporting management level requests for proposal and briefing support have been presented.
Furthermore, it is probably significant to report that the abstract for this paper and the paper itself were made possible only by using the World Wide Web. None of the authors have home offices in the same building, nor work common hours. Using the World Wide Web and hypermedia, a URL for the document was created and an ethereal token was created using an E-mail alias. As authors made contributions to each document, E-mail to the others indicated the work in progress. The amended and updated document was returned to the agreed upon URL and E-mail was sent to indicate release of the token, allowing another author to grab the token and amend the document. Amendments include not only the usual editing of a document, but the addition of hyperlinks to other pertinent URLs. The documents were completed and submitted without ever having a (physical) meeting among the authors.
Author Biographies
Mark R. Fernandez works as a Programmer/Analyst for Planning Systems, Inc., at the Naval Research Laboratory within the Stennis Space Center in Bay St. Louis, Mississippi. He is currently working on projects within NRL Code 7180 , the Acoustics Simulation and Tactics Branch, a part of the Naval Research Laboratory's Center for Applied Acoustics. One such project is the Tactical Oceanography Simulation Laboratory (TOSL) . He received his Master's Degree in Computer Science from the University of Southern Mississippi and is continuing his education as a Ph.D. student in the Scientific Computing Program, also at the University of Southern Mississippi. He can be reached by telephone at 601.688.4850 or as Mark.Fernandez@nrlssc.navy.mil via E-mail.
Dr. Jim Miller works as a consultant at the Stennis Space Center in Bay St. Louis, Mississippi. He began consulting with the U.S. Navy at NSTL in 1987 with NORDA that then became NOARL that then became NRL while NSTL became SSC. In his other life, he is a faculty member at the University of Southern Mississippi where his resume shows an extended stay at the University of West Florida and employment with IBM in the mid-sixties. It is rumored that he has his own copy of DICNAVAB. He can be reached by telephone at 601.688.4724 or as Jim.Miller@nrlssc.navy.mil via E-mail.
Jeffrey L. Becklehimer works as a physicist within NRL Code 7430, the Geology/Geophysics Section of the Naval Research Lab at Stennis Space Center in Bay St. Louis, Mississippi. He received his Master's Degree in Applied Physics from the University of New Orleans and is continuing his education as a Ph.D. student in the Scientific Computing Program, at the University of Southern Mississippi. He can be reached by telephone at 601.688.4599 or as Jeff.Becklehimer@nrlssc.navy.mil via E-mail.
Bill Maloy works as a Programmer/Analyst for Planning Systems, Inc., at the Naval Research Laboratory within the Stennis Space Center in Bay St. Louis, Mississippi. He is currently working on projects within NRL Code 7320, the Ocean Dynamics and Prediction Branch. One such project is the Ocean Tool Kit (OTK). He received his undergraduate degree in Mathematics from the University of Southern Mississippi. He can be reached by telephone at 601.688.5598 or as Bill.Maloy@nrlssc.navy.mil via E-mail.
References
[1] Tim Berners-Lee, et al, "The World Wide Web", Communications of the ACM, Volume 37, No. 8, August 1994.
[2] Open Software Foundation, OSF/Motif Style Guide, Prentice Hall, Englewood Cliffs, New Jersey, 1991.
Primary E-Mail Contact
Mark.Fernandez@nrlssc.navy.mil