A system performance throughput model applicable to advanced manned telescience systems

As automated space systems become more complex, autonomous, and opaque to the flight crew, it becomes increasingly difficult to determine whether the total system is performing as it should. Some of the complex and interrelated human performance measurement issues are addressed that are related to total system validation. An evaluative throughput model is presented which can be used to generate a human operator-related benchmark or figure of merit for a given system which involves humans at the input and output ends as well as other automated intelligent agents. The concept of sustained and accurate command/control data information transfer is introduced. The first two input parameters of the model involve nominal and off-nominal predicted events. The first of these calls for a detailed task analysis while the second is for a contingency event assessment. The last two required input parameters involving actual (measured) events, namely human performance and continuous semi-automated system performance. An expression combining these four parameters was found using digital simulations and identical, representative, random data to yield the smallest variance

Human factors workplace considerations

Computer workstations assume many different forms and play different functions today. In order for them to assume the effective interface role which they should play they must be properly designed to take into account the ubiguitous human factor. In addition, the entire workplace in which they are used should be properly configured so as to enhance the operational features of the individual workstation where possible. A number of general human factors workplace considerations are presented. This ongoing series of notes covers such topics as achieving comfort and good screen visibility, hardware issues (e.g., mouse maintenance), screen symbology features (e.g., labels, cursors, prompts), and various miscellaneous subjects. These notes are presented here in order to: (1) illustrate how one's workstation can be used to support telescience activities of many other people working within an organization, and (2) provide a single complete set of considerations for future reference

Space station proximity operations and window design

On-orbit proximity operations (PROX-OPS) consist of all extravehicular activity (EVA) within 1 km of the space station. Because of the potentially large variety of PROX-OPS, very careful planning for space station windows is called for and must consider a great many human factors. The following topics are discussed: (1) basic window design philosophy and assumptions; (2) the concept of the local horizontal - local vertical on-orbit; (3) window linear dimensions; (4) selected anthropomorphic considerations; (5) displays and controls relative to windows; and (6) full window assembly replacement

Transformation or Stagnation? The South African Defence Industry in the early 21st Century

In post-Apartheid South Africa, the ANC Government faced the challenge of restructuring an unsustainably large defence sector. This was in the context of economic and social problems and a declining international arms market. This paper considers the restructuring of the South African industry over that period and more recently, providing a valuable case study of defence industrial restructuring in a small industrialised economy. It considers how the public sector (DENEL) and private sector responded to the cuts in defence spending and the impact of the Government’s decision to modernise the South African Defence Force through foreign procurement, the Strategic Defence Package (SDP) but with extensive offset deals. Within this context the prospects for the industry and the issues surrounding the privatisation of DENEL are considered. The SDP and its offset deals is seen to be continuing to have a considerable impact on the defence industry, but is of questionable value to the South African economy. While the defence projects seem to have some successes the experience of the non defence projects is poor and overall the value of the deals is nowhere near the promises made at the outset. Lack of transparency has created a environment where corruption was almost inevitable and successful industrial planning almost impossible. While there is still some way to go, the scepticism of offset programmes expressed by Brauer and Dunne (2004) seems to be justified by the experience of South Africa.South Africa; Defence; industry

The effects of video compression on acceptability of images for monitoring life sciences experiments

Future manned space operations for Space Station Freedom will call for a variety of carefully planned multimedia digital communications, including full-frame-rate color video, to support remote operations of scientific experiments. This paper presents the results of an investigation to determine if video compression is a viable solution to transmission bandwidth constraints. It reports on the impact of different levels of compression and associated calculational parameters on image acceptability to investigators in life-sciences research at ARC. Three nonhuman life-sciences disciplines (plant, rodent, and primate biology) were selected for this study. A total of 33 subjects viewed experimental scenes in their own scientific disciplines. Ten plant scientists viewed still images of wheat stalks at various stages of growth. Each image was compressed to four different compression levels using the Joint Photographic Expert Group (JPEG) standard algorithm, and the images were presented in random order. Twelve and eleven staffmembers viewed 30-sec videotaped segments showing small rodents and a small primate, respectively. Each segment was repeated at four different compression levels in random order using an inverse cosine transform (ICT) algorithm. Each viewer made a series of subjective image-quality ratings. There was a significant difference in image ratings according to the type of scene viewed within disciplines; thus, ratings were scene dependent. Image (still and motion) acceptability does, in fact, vary according to compression level. The JPEG still-image-compression levels, even with the large range of 5:1 to 120:1 in this study, yielded equally high levels of acceptability. In contrast, the ICT algorithm for motion compression yielded a sharp decline in acceptability below 768 kb/sec. Therefore, if video compression is to be used as a solution for overcoming transmission bandwidth constraints, the effective management of the ratio and compression parameters according to scientific discipline and experiment type is critical to the success of remote experiments

Television image compression and small animal remote monitoring

It was shown that a subject can reliably discriminate a difference in video image quality (using a specific commercial product) for image compression levels ranging from 384 kbits per second to 1536 kbits per second. However, their discriminations are significantly influenced by whether or not the TV camera is stable or moving and whether or not the animals are quiescent or active, which is correlated with illumination level (daylight versus night illumination, respectively). The highest video rate used here was 1.54 megabits per second, which is about 18 percent of the so-called normal TV resolution of 8.4MHz. Since this video rate was judged to be acceptable by 27 of the 34 subjects (79 percent), for monitoring the general health and status of small animals within their illuminated (lights on) cages (regardless of whether the camera was stable or moved), it suggests that an immediate Space Station Freedom to ground bandwidth reduction of about 80 percent can be tolerated without a significant loss in general monitoring capability. Another general conclusion is that the present methodology appears to be effective in quantifying visual judgments of video image quality

A study of video frame rate on the perception of moving imagery detail

The rate at which each frame of color moving video imagery is displayed was varied in small steps to determine what is the minimal acceptable frame rate for life scientists viewing white rats within a small enclosure. Two, twenty five second-long scenes (slow and fast animal motions) were evaluated by nine NASA principal investigators and animal care technicians. The mean minimum acceptable frame rate across these subjects was 3.9 fps both for the slow and fast moving animal scenes. The highest single trial frame rate averaged across all subjects for the slow and the fast scene was 6.2 and 4.8, respectively. Further research is called for in which frame rate, image size, and color/gray scale depth are covaried during the same observation period

Childhood Mortality & Nutritional Status as Indicators of Standard of Living: Evidence from World War I Recruits in the United States

This paper examines variations in stature and the Body Mass Index (BMI) across space for the United States in 1917/18, using published data on the measurement of approximately 890,000 recruits for the American Army for World War I. It also connects those anthropometric measurements with an index of childhood mortality estimated from the censuses of 1900 and 1910. This index is taken to be an indicator of early childhood environment for these recruits. Aggregated data were published for states and groups of counties by the Surgeon General after the war. These data are related to regional data taken primarily from the censuses of 1900 and 1910. The results indicate that early childhood mortality was a good (negative) predictor of height and the body mass index, while it is also possible to predict early childhood experience from terminal adult height. Urbanization was important, although the importance declined over time. Income apparently had little effect on health in this period.

A military history of Germany: From the Eighteenth Century to the present day

The central role of the army in the historical development of Germany has long been worried- at by historians and has formed the subject of a number of specialised studies. Yet since the publicaton of Gordon A. Craig's The Politics of the Prussian Army 1640-1915 (1955) and Karl Demeter's The German Officer Corps in Society and State 1640-1935 (1965), there has been no attempt to synthesize the findings of these monographs into a book capable of appealing to the general reader until the publication of A Military History of Germany.Keywords: Military History of Germany; MARTIN KITCHEN; Weidenfeld & Nicholson; role of the army in the historical development of German

Bridging the Divide in Cultural Capital? A Tale of Two Capitals

More critical approaches are required in understanding the dynamics of creative economy and the interplay between its social, political and economic dimensions. Among the key contributions to the economic analysis of the creative economy are economist David Throsby, including his concept of ‘cultural capital’. This concept provides new ways of thinking of culture and value, primarily within a defined economic discourse. We also consider the work of Pierre Bourdieu on cultural capital and suggest that some form of synthesis of the two approach opens up possibilities. For one, such an exercise opens up debates within the academic discipline of economics, and secondly it allows fruitful interaction between economics and other social science discourses both disciplinary and transdisciplinary. It also provides us with understanding of the workings of the global economy and at a more abstruse level, to the ways in which contemporary capitalism is structured within the global economy.   https://doi.org/10.19108/KOERS.87.1.253