Human factors aspects of a modern data base system

The focus of this work is to develop tools and procedures so that non-computer specialists can more effectively manage and use data. The results of several research projects over a number of years have given a spectrum of approaches to make data systems easier to use. In our work, the relational model of data was simplified so that novice users could easily understand their data relationships. An algebraic relational command language was developed to bring the power of relational data manipulation to non-programmers. This research was followed by development of an extended command system that allows users to name and describe their data in English words rather than in cryptic abbreviated forms. In parallel with this, a menu interface to a relational system was developed. The degree of completeness of these approaches, the overall effectiveness in actual operation, some data collected from users, and the ease of learning have been analyzed and are reported.     

The building of a computer-based teaching system

This paper argues that: (1) conventional all-purpose author languages inhibit, rather than promote, the active involvement of expert teachers in computer-based learning; and (2) a computer-based teaching system cannot be totally pre-specified, but must be conceived as a growing collection of software tools which enable the author or teacher to construct integrated courseware using only those facilities within the system which correspond directly to the task in hand.Instead of recommending author languages, such as PILOT, which tempt the teacher to write programs that respond to students in the manner of a classroom dialogue, it is suggested that the production of interactive teaching material should be based on frameworks which enable the author to separate out differing teaching functions and tasks: these include the detail of the subject matter (content); the layout on the screen (presentation); the style of the exchange between student and machine (interaction); and the interlinking of student activities (structure).A teaching system is considered as a set of authoring tools providing such frameworks. By using these individually, or in combination, the author can produce small units or modules of teaching material. The teacher may integrate such modules, which have been developed by a number of authors employing different methods, into a coherent purpose-built computer-based course suited to his students (curriculum). A teaching system so constructed, however small it is initially, can be built up to incorporate more software tools satisfying newly identified needs without having to abandon the fruits of earlier work, and consequently a wealth of teaching material in a variety of styles may be accumulated from which numerous courses can be created.In justifying these views, detailed reference is made to the system, GALTS, which is used by teaching staff at Leeds University.     

Reducing cognitive workload of a computer-based procedure system

The use of procedure systems is an important safety management strategy in coping with emergency or abnormal situations in a process control system. With the digitalization trend in these complex and large-scale systems, most aspects of a process control system are also computerized. In addition to the primary tasks, operators now have to do extra secondary tasks when using the computerized systems. In this research, three design features aimed to reduce the cognitive workload are evaluated on our research platform, SimCBP and SimPlant. These two systems work in tandem to simulate a Computer-Based Procedure (CBP) system and a simplified nuclear power plant. From the results of the experiments, the design of embedded controls/parameters is found to be efficient but its counterpart has implications for the design of training materials. Navigation aid, although not statistically significant, is important because of the subjective responses and the need of cross-referencing. The simplified flowchart display format, like other researches on the use of this format, revealed mixed results. Implications and directions for future studies are also proposed.     

The use of graphics in a computer-based urban information system

This paper describes the development of an interactive graphics system for the display of planning information in urban areas. It outlines the objectives of the system and explains the content and structure of the various data files. It goes on to explain the user operating environment and the provision of suitable graphics facilities. By way of examples it demonstrates the potentialities of the system.     

BINYAS: a complex document layout analysis system

Multimedia Tools and Applications - Document layout analysis (DLA) is an irreplaceable pre-requisite for the development of a comprehensive document image processing and analysis system. The main...     

The effects of simulating human conversational style in a computer-based interview

A computer interview involves a program asking questions of the user, who responds by providing answers directly to the computer. Using a computer interview has been shown to be an effective method of eliciting information, and particularly personal information which many people find difficult to discuss face to face. While the simulation of some of the characteristics of human–human communication seems to enhance the dialogue, it appears to be the absence of others, such as being non-judgmental, unshockable, completely consistent, and unendingly patient, that gives computer interviewing its particular effectiveness.

The work reported in this paper investigated the effect of simulating in a computer interview two techniques which good human interviewers use: empathy and grouping questions. Thirty nine interviewees answered 40 questions on a computer, in combinations of human-like or computer-like question styles, and presented in either a logical or a random order.

They found the use of the human interviewer technique in the wording of questions made the computer interviews more interesting and enjoyable, than when blunt, direct questioning was used, and they answered honestly more often to the human-like style.

This investigation has shown that a computer interview can be made more effective by simulating the human interviewer technique of empathising with interviewees and softening those questions which are of a sensitive nature. It seems therefore that it is the combination of the right non-human characteristics with the right human characteristics that can produce a successful computer interview. The question for further research is which are the right characteristics in each case, given the purpose of the interview.     

Modelling and estimating the pose of a human arm

Pose estimation of 3-D objects based on monocular computer vision is an ill-posed problem. To ease matters a model-based approach can be applied. Such an approach usually relies on iterating when matching the model and the image data. In this paper we estimate the 3-D pose of a human arm from a monocular image. To avoid the inherent problems when iterating, we apply an exhaustive matching strategy. To make this plausible, we reduce the size of the solution space through a very compact model representation of the arm and prune the solution space. The model is developed through a detailed investigation of the functionality and structure of the arm and the shoulder complex. The model consists of just two parameters and is based on the screw-axis representation together with image measurements. The pruning is achieved through kinematic constraints and it turns out that the solution space of the compact model can be pruned , on average. Altogether, the compact representation and the constraints reduce the solution space significantly and, therefore, allow for an exhaustive matching procedure. The approach is tested in a model-based silhouette framework, and tests show promising results.Published online: 8 August 2003Correspondence to: Thomas B. Moeslund     

Optimisation of construction site layout using a hybrid simulation-based system

The layout of temporary facilities for a construction project greatly impacts project performance as demonstrated in many prior studies. This paper demonstrates how the site layout process can be automated for specific types of construction. Utility tunnel construction was selected as the specialty area, for which a partially automated site layout application was built. This approach integrates general purpose simulation for modelling space, logistics and resource dynamics with genetic algorithms for optimizing the layout based on various constraints and rules. We achieve this by implementing a site layout optimisation system within a simulation environment which already models tunnel construction processes. The new modelling strategy provides a medium for seamless integration between the resulting site layout and the discrete event production simulation models. The paper describes the approach taken and the system developed, presenting a practical case study from a tunnelling project in Edmonton, Canada to illustrate the system’s performance and its validation.     

Modelling and simulation of a lighting control system

The objective of this paper was to regulate the amount of illumination in a room at a constant level, irrespective of the disturbances from outside such as weather conditions or the use of blinds to avoid the glare risk. In order to produce a model of the lighting system in our project, the supply voltage to the lamp dimmer circuits was varied stepwise and the resulting response – measured by the light sensors – was captured with a data-acquisition board. A nonlinear static characteristic in series with a linear 3rd order dynamic system was obtained from this experiment. The model was then used to implement and to validate a lighting system simulator, which was then further used to design, tune, test and evaluate efficient lighting controllers. The control design was rather challenging because the system is highly nonlinear and because undesired interaction occurs between multiple illumination zones in a big office room. The main benefits are a higher level of comfort and a continuous saving of energy.     

SENEX: a computer-based representation of cellular signal transduction processes in the central nervous system

The SENEX project is exploring knowledge representation in the neurobiology of ageing through object-oriented programming. SENEX is built from a classification structure of biologic entities and significant relationships among them. For example, an enzyme is an entity and an enzymatic reaction is a relationship among enzyme, cofactor(s), substrate(s) and product(s). There are currently 2600 classes of entities and 50 classes of relationships in SENEX. The class structure serves several functions. One function is to interrelate general and specific categories of molecular and morphologic entities. For example, tyrosine kinase and serine/threonine kinase are specific types of the more general class of protein kinase enzymes. Another function of the class structure is to serve as a network through which inheritance of attributes may occur. For example, the attribute 'subunits' is inherited by all subclasses of the general class multisubunit protein. Information may be accessed through links established in the class structure and through links relating one object as part of another. Relationships form the basis of separate modules within SENEX. This paper describes the types of relationships currently used and planned in the representation of age-related changes in cellular signal transduction processes of mammalian central nervous systems. We also describe tools for specific retrieval of relationships and for tracing links in complex reaction cascades. Application of these tools to identifying possible signal transduction pathways to guide further exploration through experimentation is discussed.     

A computer-based system for the acquisition and analysis of data from a field tillage study

A computer-based data acquisition system is described that enables both continuous real-time control of data collection from some 250 sensors deployed at a remote field site, and immediate conversion from analogue data to the required physical parameter. In addition, data analysis programs can be developed and run concurrently with data collection. Important aspects of the computer operating system are discussed, as is the overall programming strategy for a field experiment. An account is given of the control of scanning and measuring instruments (connected to the computer via a standard parallel-interface bus), and of the technique adopted for utilizing the file management software to store processed data in an easily retrievable form. A FORTRAN program to control the measurement of soil temperatures is discussed; and an assessment is given of the equipment's performance in use.     

POMME: a computer-based consultation system for apple orchard management using Prolog

Abstract: Direct dissemination of expert knowledge to agricultural producers through computer programs will increase product quality as well as the profit margin. The construction of an expert system, called POMME, to help farmers manage apple orchards is reported here. The system provides advice regarding specific pest management, treatment of winter injuries, drought control and general pesticide selection. A sample interaction is provided, and the knowledge structures employed in the construction of the system are explained. A model of the apple scab disease cycle is incorporated into POMME to give the system a more fundamental reasoning capability than available from typical rule-based systems.     

A structural equation model of job performance using a computer-based order entry system

The research uses a structural equation model with latent variables to examine the role of computer self-efficacy and outcome expectancy in impacting job performance. Constructs measuring management support, ease of system use, and the previous computer experience of the user are used as antecedents to computer self-efficacy and outcome expectancy. The empirical results are generated using 524 responses to a questionnaire administered in a large hospital in the southeastern United States regarding its computer-based order entry system. These results provide empirical support for the theoretical role of computer self-efficacy and outcome expectancy positively impacting job performance. Further, the antecedents were found to have the expected positive impacts on computer self-efficacy and outcome expectancy.     

Modelling adaptive hypermedia instructional system: a framework

Multimedia Tools and Applications - This research drill presents a perspective on modeling an Adaptive Hypermedia Instructional System (AHIS), by integrating investigational research findings on...     

Modelling and control of a wind energy conversion system

The dynamical model of a novel low power wind energy conversion system consisting of a wind turbine, an induction generator, a PWM a.c. inverter and a d.c. battery group is obtained. A feedback control law is developed to provide optimum power conversion and arbitrarily fast responses at steady-state. The feedback does not require measurement of the wind speed and therefore is suitable for real applications. The stability of the closed-loop system is analysed using a Liapunov-type practical stability criterion, and it is shown that the system remains stable for wind speed variations that are not both large and fast at the same time. Digital computer simulation studies on a 1 kVA test system verify the theoretical results.     

Economical aspects of a data management system

Much interest has focused on generalized data management systems. This paper takes a hard look at one of these systems—MIRADS.     

Impact on the management and delivery of primary health care by a computer-based information system.

Timely and accurate information forms the basis for management to plan and for care providers to take appropriate action. We report from a developing country a research project aimed to strengthen the information infrastructure with a computer at a Primary Health Centre. The software (MCHS) was designed to assist the care providers in the information management for the Maternal and Child Health (MCH) programme activities. In Phase I, a baseline survey was conducted to identify the needs and target groups. In Phase II, the MCHS was integrated into routine delivery of MCH to monitor the target population and help in evaluation. The research project's impact is reflected in enhanced utilization of services and quality in care, as seen by reduction of dropouts from the immunization program. In economic terms, we see that the costs for a fully immunised child are reduced with reduction of dropouts; thus, the computer system contributes to quality assurance and cost effectiveness in delivery of care.