Science and application payloads in the 1990's

During the 90's with the operation of the Extended Duration Orbiter (EDO), Space Station Freedom (SSF), large platforms in polar and Geosynchronous orbits around the Earth, and supporting systems and technology, an infrastructure will exist that will offer a wide range of opportunities for science and applications payloads. The Marshall Space Flight Center (MSFC) is in a unique position of studying for NASA science missions for all of these systems. This paper will discuss a variety of payloads being studied for NASA at the MSFC that are scheduled for flight in the 90's, in support of space science and Mission to Planet Earth. These science payloads such as the Controls, Astrophysics and Structures Experiment in Space (CASES), Advanced Solar Observatory (ASO), Laser Atmospheric Wind Sounder (LAWS), and Lightning Imaging Sensor (LIS), etc. will fully utilize the capabilities of EDO, SSF, Earth Observing System (EOS), and Earth Science Geostationary Platform (ESGP). Emphasis will be placed on showing how these scientific payloads can fully exploit the great potential of these new capabilities for exciting new science and application missions

The Social Life of Information Systems Research: A Response to Benbasat and Zmud\u27s Call for Returning to the IT Artifact

Benbasat and Zmud (2003) argue that there is an identity crisis within the Information Systems discipline and, as a solution to the crisis, propose a focus on ¡°the IT artifact and its immediate nomological net¡± (p. 186). Using Aldrich¡¯s (1999) articulation of organizational evolution, they note the need for greater cognitive legitimacy as a driving force for sustainability of the discipline. They recommend that researchers and journal editors set the boundaries of the field more firmly so that greater attention is given to the IT artifact rather than to structure, context, or other phenomena that lie distant from the artifact. An alternative analysis of the IS field can be made through the lens of community of practice. Here the indicators suggest more positive progress toward legitimacy of the IS field and a path toward improvement via boundary enhancement rather than constraint. Other recommendations for improving the sustainability of the discipline include greater attention to research questions of current interest, even if they are peripheral to the artifact, greater communication of theory and empirical research results, and continued attempts to build and sustain active membership

Analysis of H/W & S/W techniques for data reduction in high speed digital image processing

With the widespread utilization of charge-coupled-devices, there is much interest in methods to efficiently process images. The processing, manipulation, and storage of photographic quality digital images place significant demands on today\u27s computers. Even with today\u27s high performance bus structure and real-time operating systems, manipulating full resolution image data may quickly overwhelm computer hardware and software. In response to this, data reduction techniques have been developed to aid in resolving this problem. Two common data reduction techniques include data sub-sampling and data averaging. Data sub-sampling approach is simplistic in nature and perhaps easiest to implement in both hardware and/or software. This approach involves sub-sampling the full resolution image data to a lower resolution. Selection of sub-sampled element of the full resolution image is random in nature. This random selection makes sub-sampling an effective technique for flat image fields but degrades or softens the image for edges information quality/content. Data averaging approach is more difficult and complex to implement in both hardware and software than the sub-sampling approach. The data averaging approach involves a two dimensional averaging function to sub-sample the full resolution image data to a lower resolution. Averaging area parameters may be chosen to average X consecutive pixels, and Y consecutive lines. Although more complex, data averaging more effectively retains edge information. This thesis investigates the two-dimensional, pixel data-averaging method for data reduction. It supports the use of a pixel-averaging algorithm in conjunction with, or independent from compression techniques which may be employed elsewhere within the same system. Hardware and software implementations are presented to solve this system problem. The hardware architecture design is based on a pixel averaging application specific integrated circuit. Software routines written in C programming language are presented to perform this data-averaging task. Performance comparisons are made between the hardware and software implementations for image resolutions up to 2048 by 3072 pixels, and under several averaging conditions. This thesis also provides a survey of various types of charge-coupled devices sensors, focusing on their abilities and limitations for data averaging. It presents several applications where this type of data reduction would be advantageous

Mobilizing Informational Social Capital in Cyber Space: Online Social Network Structural Properties and Knowledge Sharing

Online networks can be construed as social networks in which people engage in interactions, build rela- tionships, share information, and request and extend assistance to each other using electronic communication technologies. Is social capital embedded in online networks? How is such social capital mobilized (i.e., shared)? What structural properties of cyber networks are associated with mobilization of social capital? These questions have drawn the attention of researchers in the areas of social networks, social capital, and online communication. Our research is an initial effort to touch upon these three questions. Whereas most previous research on both conventional and online social networks has favored analysis of either egocentric (i.e., individuals) or bounded (i.e., groups or organizations) networks as the primary unit of analysis, this study investigates online discussion forums that span formal boundaries of organizations, examining their structural properties and patterns of information exchange. We employ a network-based approach to the study of social capital, postulating that mobilization of social capital is contingent on social network properties. Using data from professional online forums devoted to knowledge management, we find that two network properties, core–periphery structure and centralization, are related to the mobilization of informational social capital in online networks. Implications and limitations of this study are discussed and suggestions for future research are provided

An Investigation of the Tables Versus Graphs Controversy in a Learning Environment

The study of computer graphics as decision aids has become popular among MIS researchers in the last several years. However, this area of research, like many others in management information systems, has been plagued with methodological problems and contradictory findings. In light of these difficulties, the current study examined the tables versus graphs controversy within a learning environment. Seventy-five MBA students were exposed to one of three experimental treatments and asked to develop financial forecasts for fictitious companies over five experimental trials. Following their forecasts for each firm, participants were provided with feedback on the quality of their decisions. The information presentation treatments were as follows:(l) traditional spreadsheet (tabular), (2) graphs using standard scaling, and (3) graphs using nonstandard scaling. Results suggest that, although graphics may initially demonstrate no advantage over tables, they do show an advantage i f decision makers are repeatedly exposed to the novel format and given feedback on their performance. L. arning will occur even when improper scaling is used. The implication is that the effectiveness of graphics as decision aids depends on practice. Researchers are encouraged to employ repeated measures, or longitudinal, designs when examining the tables-versus-graphs controversy

The Dynamics of Teams and Technology: A Field Study of Groupware in a Network Organization

Groupware technology, such as electronic communication systems, discussion databases, collaborative writing tools, and workflow applications, has been viewed by both scholars and practitioners as having the potential to facilitate productive teamworkandenableanorganization’stransitiontotheso-callednetworkdesign. Networkedorganizationsrelyonmultiparty cooperative relationships across structural and geographic boundaries, yielding dense, flexible communication patterns. Because groupware systems provide a platform on which teams can support their communication needs and shared work obligations, teams which use groupware should experience improved information exchange and fewer coordination problems than those that do not. Further, organizations that invest in groupware systems should make more rapid progress toward a network form than those that do not. The added value of groupware, relative to more primitive forms of communication support, should increase as team members become more facile in new technology use and modify their work practices to accommodate computer-mediated collaboration

Panel 11 The Web and IS Academics: An Opportunity or a Trap?

The area of Information Systems research has been blessed — or cursed — with fast evolving subjects of study that have created a lot of hype, captured the attention and imagination of wide audiences, and generated a significant demand for corresponding literacy and skills. At the moment, it seems that none of these — the use of computers for the management of large scale operations, the augmentation of human intelligence, and personal computing — has become such a broadly referred phenomenon as the Internet and its related uses, most prominently the World Wide Web

Understanding the Effectiveness of Computer Graphics for Decision Support: A Cumulative Experimental Approach

A total of 840 junior and senior-level undergraduate business students participated in three experiments which compared computer-generated graphical forms of data presentation with traditional tabular reports. The first experiment compared tables and bar charts for their effects on readability, interpretation accuracy and decision making. No differences in interpretation accuracy or decision quality were observed for the two groups, although tabular reports were rated as more easy to read and understand than graphical reports. The second experiment compared line plots with tables for their effects on interpretation accuracy and decision quality. Subjects with graphical reports outperformed those with tables. There were no meaningful differences in interpretation accuracy across treatment groups. The third experiment compared graphical and tabular reports for their ability to convey a message to the reader. Only in situations in which a vast amount of information was presented and relatively simple impressions were to be made, did subjects given graphs outperform those using tables. This program of cumulative experiments indicates that generalized claims of superiority of graphic presentation are unsupported, at least for decision-related activities. In fact, the experiments suggest that the effectiveness of data display format is largely a function of the characteristics of the task at hand, and that impressions gleaned from one shot studies of the effectiveness of the use of graphs may be nothing more than situationally dependent artifacts