Iowa State University From the SelectedWorks of Steven A. Freeman

1994

Rural Assistive Technology Hypermedia Decision Support System Steven A. Freeman, Purdue University Don D. Jones, Purdue University William E. Field, Purdue University

Available at: http://works.bepress.com/steven_freeman/36/

RURAL ASSISTIVE TECHNOLOGY HYPERMEDIA DECISION SUPPORT SYSTEM S. A. Freeman, D. D. Jones, W. E. Field A prototype hypermedia decision support system for the selection and documentation of rural assistive technology (BNG DATA) was developed to aid professionals working with farmers, ranchers, and agricultural workers with physical disabilities. The hypermedia system (constructed using HyperCard, an environment that combines hypertext and database features) consists of a hypermedia database of rural assistive technology examples and an accompanying decision support system that helps users identify solution alternatives to meet the needs of their clientele. End user acceptance of BNG DATA was determined using an evaluation questionnaire. The end users evaluating the prototype considered BNG DATA to be easy to learn, easy to use, and unanimously considered BNG DATA to be a valuable resource that they would like to have for their own use. Using a statistical experiment in conjunction with the questionnaire, it was also concluded that BNG DATA significantly reduced the amount of time required by end users to find acceptable solution alternatives for their clientele (a = 0.01) and increased the end users' confidence in the solutions they obtained (a = 0.10). This article describes the development and testing of BNG DATA, focusing on the steps taken to ensure end user acceptance. Keywords. Knowledge systems, Hypertext, Information systems, Decision support systems, Database. ABSTRACT.

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n the past, there has been little documentation of assistive technology appropriate for use by farmers and ranchers with physical disabilities. The lack of historical documentation and the scarcity of expertise in this area have forced many rehabilitation professionals working with farmers with physical disabilities to make decisions regarding the selection of assistive technology* without adequate guidance. Inadequate information concerning the available choices and selection criteria for identifying appropriate characteristics of assistive technology have frequently resulted in problems. These include the waste of time, energy, and resources in "reinventing of the wheel" by those who believe that they are attempting to solve unique problems. Other serious consequences of the uninformed selection of assistive technology include an increase in the risk of injury to the operator and/or bystanders due to unsafe designs or practices used to accommodate a disability and the increased potential for abandonment of the technology. There is an increasing demand for rural assistive technology expertise brought about by the Americans with Disabilities Act and increased disability awareness among

the general public. Current experts do not have the time and/or resources to meet this increasing demand. The prototype rural assistive technology hypermedia decision support system (BNG DATA) is designed to meet this need for additional expertise by allowing less experienced personnel to take advantage of the expertise developed at the Breaking New Ground (BNG) Resource Centerf over the past decade in providing technical assistance to farmers, ranchers, and agricultural workers with disabilities. This article describes the development and testing of BNG DATA, focusing on the steps taken to ensure end user acceptance. While the problem domain involves rural assistive technology, the techniques described are applicable to a variety of problems covering a range of topics.

ACCEPTANCE OF DECISION SUPPORT SYSTEMS There is no single methodology that decision support system (DSS) developers can follow to guarantee a successful project. However, the authors' experiences in developing decision support systems (both successfully and unsuccessfully) may provide insight into how one might increase the likelihood that the system will be accepted and Article has been reviewed and approved for publication by the used by end users outside of academia. Specifically, these Information and Electrical Technologies Div. of ASAE. Presented as issues are: (1) the knowledge incorporated into the system ASAE Paper No. 93-3038. Support for this work was provided by the National Institute on needs to be scarce, (2) the DSS needs to be designed with a Disability and Rehabilitation Research, Grant No. H133A90004-90. specific target audience in mind, and (3) the end user needs The authors are Steven A. Freeman, ASAE Member Engineer, to be presented with a finished, professional product. Each Agricultural Safety and Health Specialist, Don D. Jones, ASAE Member Engineer, Professor, and William E. Field, ASAE Member, Professor, of these issues is discussed in turn. Dept. of Agricultural Engineering, Purdue University, West Lafayette, Ind. * Assistive technology is any item, piece of equipment, or product system, whether acquired commercially off the shelf, modified, or customized, that is used to increase, maintain, or improve functional capabilities of individuals with disabilities. Rural assistive technology refers to the aspects of assistive technology that are unique to the agri-

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The BNG Resource Center at Purdue University has become widely recognized as one of the leaders in the field of rural assistive technology especially as it relates to the agricultural workplace.

Applied Engineering in Agriculture VOL. 10(6):823-830

© 1994 American Society of Agricultural Engineers 0883-8542 794/1006-0823

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SCARCE KNOWLEDGE

PROVDMNG A PROFESSIONAL PRODUCT

The problems that developers choose to solve should involve valuable, needed knowledge that is not readily available to the end users. This can be done by focusing decision support systems (DSSs) work on specialized topics that are not addressed by traditional agricultural information sources. For many problems, traditional information sources such as the Cooperative Extension Service (CES), agribusiness (e.g., lenders, implement dealers, chemical suppliers, veterinarians, farm media), and other specialized sources [e.g., Soil Conservation Service (SCS), farm organizations] have advantages over DSSs: 1. Knowledge obtained from traditional information sources is relatively inexpensive and is often publicly supported, such as CES and SCS. 2. Traditional information sources allow for direct personal contact between the client and the expert allowing the client to ask questions about areas that are unclear and thus obtain clarification and/or additional information immediately. 3. Knowledge from traditional information sources is available in a variety of formats including print media, radio, and television. Examples of specialized topics that are not addressed by traditional agricultural information sources includes aquaculture and new "non-mainstream" technology issues such as specialty crop production and the selection of rural assistive technology.

Development of many of the DSSs produced by academia appears to stop with the development of the knowledge base. Jones and Barrett (1989) state: "Often the struggle to complete the knowledge base is so difficult and time consuming, developers have little energy left for the user interface." However, if these systems are going to be used outside of academia, the developers (and their funding sources) must recognize the importance of the user interface and other aspects of the total system beyond the knowledge base. The DSSs are competing for the time of busy end users. The overall package associated with the DSS will likely define how competitive the system is. The ideal method of representing information is to combine different media formats to suit the information being presented. However, if the concepts presented involve motion, visual interpretations are generally easier to understand. In the words of Van Dam (1988): "If a picture is worth a thousand words, a dynamic picture of time-varying objects is worth a thousand static ones. We need dynamics . . . not just static pictures and text". If a software package is to be successful, support must be provided for the system, just as equipment manufacturers must support their products with competent parts and service departments at their dealerships. In addition to the maintenance and upkeep required by traditional software packages, DSSs are also susceptible to becoming outdated as technology advances within the knowledge domain.

DESIGNING FOR THE END USER

The importance of clearly identifying appropriate end users can be illustrated by the fact that there have been many agricultural decision support systems developed at Purdue University as part of research projects that were later abandoned once the projects were completed or funding ran out. While useful to those working on the project at the time, these DSSs were rarely developed to a point that allowed them to be used outside of academia. In fact, potential users of these decision support systems were often sought only after the systems were completed. For these instances, the lesson was clear. For a DSS to be successful beyond academia, the end users and their needs must be clearly defined before development begins. Identifying end user characteristics helps identify constraints under which the DSS must operate. These include information such as the end users' occupation, educational background, and computer literacy. A second step is to identify a narrow target audience as well as a narrow problem domain. Depth is more important (valuable) than breadth in the knowledge base of a DSS (Giarratano and Riley, 1989; Jones and Barrett, 1989; Waterman, 1986). The scope of the DSS needs to be narrow enough to make the recommendations and solutions practical and useful. The third step in designing for the end user is to involve the end user in the design process. Whenever possible, the end user should be involved in the entire process— conceptualization, development, testing, and validation. End user involvement is important to ensure that the DSS provides end users with what they need, what they want, and provides the knowledge in a format that they are familiar with and comfortable using.

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METHODS The following procedures were used in the development of BNG DATA: (1) evaluation of hardware and software alternatives, (2) development of the prototype rural assistive technology database, (3) development of the prototype DSS, (4) development of the methods used for evaluation of BNG DATA, and (5) testing and evaluating BNG DATA. EVALUATION OF HARDWARE AND SOFTWARE ALTERNATIVES

Three computer platforms were considered for the development and distribution of BNG DATA: (1) IBM PC compatible, (2) Apple Macintosh, and (3) UNIX-based workstations. A summary of the criteria considered with respect to the capabilities of available computer platforms is shown in table 1. The advantages and disadvantages of each platform with regards to this project are discussed in more detail in Freeman (1993). The Apple Macintosh was chosen because: (1) Macintosh systems dominate the majority of the rehabilitation centers and rehabilitation professionals make up a significant portion of the Table 1. Summary of selection criteria with respect to the capabilities of available computer platforms Selection Criteria Graphics capabilities Video capabilities without additional hardware User acceptance Cost Large disk storage Ease of providing secure backups Dominate platform among potential end users

IBM PC

Mac

UNIX

X

X X X X

X X

X X

X X X

APPLIED ENGINEERING IN AGRICULTURE

File Go DSS 9:22 AM O ^» anticipated end users of BNG DATA, and (2) the National Rehabilitation Information Center uses a Macintosh based VERTICAL SCREW CHAIRLIFT system for the distribution of their ABLEDATA™ Problem: Accessing a heavy equipment seat by operators with lower extremity impairments database^. A UNIX file server was utilized to provide a Solution: A lift that can raise the operator to the level of the secure daily backup of BNG DATA and for some of the equipment seat image manipulation. Description: page 1 of 2 O The Versalift provides access to tractors compines and other The software package chosen was HyperCard™ from agricultural vehicles and is designed for all-weather operation Each unit consists of a vertical sciew with l i f t motor, two swing arm drive Apple because (1) HyperCard version 2.1 has the textual, motois, and a swing arm with a seat Moving at roughly four feet per minutd graphical, and video capabilities desired for the rural Supplier: in bott lited numbe assistive technology database, (2) HyperCard is distributed import Cost: (As of August 1991) ope itetnal with the Macintosh system software and thus does not inslip cl n the volve any distribution license for the developers or event $5350 S/H and installation not included $5SO0, S/H and installation not included additional software requirements for the users of the operation Dual controls are standard One set travels with the seat system, and (3) HyperCard is the software that the Trace while the other set is installed inside the cab The system operates on electricity from the existing equipment power supply R&D Center will continue to use for the distribution of Maximum l i f t capacity is 275 pounds with a minimum ground clearance ABLEDATA as Hyper-ABLEDATA. Other software of 24 inches versalift is sold in standard heights of four, six, and eight packages considered for the database were MacroMedia Director™ and Aldus SuperCard™, neither of which may Figure 1-Example of screen design and textual information included be distributed without a licensing fee. CLIPS™ was the in the database. software of choice for the DSS until it was determined that the domain knowledge could be structured in such a way browsed by proceeding from article to article linearly, by that a formal rule-based system was not required for the utilizing the organizational menu structure, or by utilizing DSS. HyperCard's built-in full-text search capabilities. The fulltext search capabilities allow the user to search for words or phrases anywhere in the database or in particular fields DEVELOPMENT OF THE PROTOTYPE DATABASE The basis of the BNG DATA database was Agricultural such as the title, supplier, or description. The database expands on the structure and form of the Tools, Equipment and Buildings for Farmers and Ranchers with Physical Disabilities - Volume II (Brusnighan et al., information available in printed resources by also including 1991). The prototype database was implemented as a high resolution color pictures, digitized video sequences of HyperCard stack containing the same textual information the technology in use, and the indexing features inherent to as the hard copy resource manual and additional hypertext applications. See figures 1 and 2 for examples of information in the form of color pictures and video the screen design and the types of information included in the database. Figure 1 shows the general screen layout and sequences. The steps required were as follows: (1) designing the how additional textual information is presented. Figure 2 user interface and screen layout for the database, (2) taking shows an article with a color picture and a video sequence the textual information from electronic storage, removing being displayed. The help features for the database were typesetting commands, and inputting the textual approached with simplicity in mind. The help facilities information into the appropriate fields in the database, consist of one card that is accessible from every card in the (3) digitizing color slides of the technologies in the database (both articles and menus). This card contains a database, (4) image processing to prepare the digitized copy of every button that exists in the database. By slides for use in the database, (5) selecting the video selecting any button on the help screen, the user is given an sequences to be digitized, (6) digitizing the video explanation of what that button does and how to use it. sequences, and (7) incorporating the images and video sequences into the database. The prototype database was organized similarly to " ~'~_" - - - - - - — ~ " _ ilNMHtTlj current resources produced by the BNG Resource Center. AH "TCmi A IN" WI (ma fA Following the organization of the current resources, the database is divided into eight major sections. Each section is then further divided into related topics. Each topic consists of individual examples of rural assistive technology. For example, a specific example of hand control modifications for tractor brake pedals is under the topic titled, Modifications for Brakes, which is under the section titled, Control Modifications. As another example, under the section titled, Lifts and Techniques for Accessing Agricultural Equipment there is a topic titled Tractors Chairlifts, which includes a specific example of a vertical screw chairlift as shown in figure 1. The articles may be

ABLEDATA is a database of over 17,000 assistive technology products for use by the general public. Distribution will continue as Hyper-ABLEDATA through the Trace R&D Center at the University of Wisconsin-Madison.

VOL. 10(6):823-830

Figure 2-ExampIe of pictures and video sequences as part of the database.

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Additional details about the development of the database can be found in Freeman (1993). The hypermedia system was designed as a supplement not as a replacement for the hard copy resources that are currently available, and will be available in the future. With this in mind there were no printing facilities built into the database. The users of the database already have a hard copy description of all of the technology in the database. The funding for the hard copy resource documentation is an ongoing effort of the BNG Resource Center and will continue regardless of the outcome of the prototype hypermedia system. If in the future the two separate efforts are to be combined, then print capabilities will become important. Until that time, much better quality images are included in the printed resource material than can be produced on the average laser printer. However, if the user would like to quickly produce output to give to the client, the capability to print what is on the screen is built into the Macintosh operating system. DEVELOPMENT OF THE PROTOTYPE DSS

The steps required to complete the prototype DSS were as follows: (1) identifying the domain experts, (2) establishing the format needed by the end users, (3) developing the DSS questions and the corresponding keywords to be used as search criteria, (4) assigning keywords to each article in the database as deemed appropriate by the domain experts, (5) designing the user interface and screen layout for the decision support system, (6) implementing the keyword search methodology in HyperCard, and (7) incorporating the expert selected keywords into each article in the database. The domain experts chosen were William E. Field and Dean A. Brusnighan. Dr. Field is recognized by colleagues and peers to be a leading authority in the area of rural assistive technology. Dr. Field is the director of the Breaking New Ground (BNG) Resource Center and is currently responsible for coordinating training, support, and resources to the 16 state demonstration sites established by the USDA Education and Assistance Program for Farmers and Ranchers with Disabilities (AgrAbility) (Extension Service, 1992). Mr. Brusnighan is a rehabilitation engineer associated with the BNG Resource Center. He is the staff person responsible for documenting rural assistive technology and responding to inquires concerning the application of assistive technology in agricultural workplaces. While HyperCard's full-text search capability mentioned above is a useful feature, it does not help the end user select technology that is appropriate for the needs of a particular client. The expertise of the domain experts can be utilized to meet this need. To use the domain experts' knowledge and experience to select appropriate technology, a keyword search methodology was chosen because (1) it provides the end users with appropriate information to aid them in making rural assistive technology selection decisions, (2) it requires few user inputs and the inputs are selected from a list so the end user does not need to know what keywords the domain experts were considering, (3) it implemented the DSS as an extension to the database rather than a separate entity, (4) it was easy to program and maintain compared to a rulebased methodology, (5) the domain experts could easily

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assign keywords to each article in the database, and (6) identified solutions were easy to control and update using the keyword approach rather than a full-text search. Figure 3 shows how the user selects keywords to be used for search criteria. The purpose of the DSS was to provide end users with solution alternatives, rather than a specific solution, that they can then discuss with their clientele. The intended end users are professionals who are capable of recognizing irrelevant solutions. These professionals, however, may not have the experience in the problem area to recognize as many possibilities as the domain experts. Therefore, it is more helpful for the DSS to have breadth rather than depth in the solution alternatives it provides. Providing suggestions, that end users will then discuss with their clientele, rather than solutions also encourages consumerdriven selection of technology which in the long run will decrease the likelihood of the technology being abandoned after it has been implemented. For greater details on the selection process and using the DSS to aid agricultural workers with physical disabilities see Freeman and Field (1994). DEVELOPMENT OF EVALUATION PROCEDURES

Before the evaluation to determine if BNG DATA was practical for "real life" use, had benefits for the end users, and would be accepted by the end users, three preliminary steps were required: (1) the development of test cases, (2) the design of a statistical experiment, and (3) the development of a questionnaire to determine end user acceptance. Development of Test Cases. Two test cases were developed with the help of the domain experts and the BNG Resource Center's information specialist, Melissa Deason. Each test case consisted of a letter from a potential client asking for assistance. The test cases were intended to be representative of the clientele currently being served by the BNG Resource Center. Each letter contained sketchy details and language similar to the letters received by the BNG Resource Center, and each letter contained two distinct problems that needed to be addressed. The first test case represented a row crop farmer with a spinal cord injury. This letter consisted of a farm wife File

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