Free Space Optics - Transportable Test Platform

The study examines potential approaches and benefits to government space agencies and industry regarding the development and testing of free space optics (FSO) satellite communication systems should government space agencies launch optical satellite payloads and/or develop a transportable test platform with which industry provided optical ground systems (OGSs) could interface. The study examines atmospheric and environmental effects on FSO networks, as well as the multitude of mitigation techniques available to compensate for those effects. Research suggests that there are a multitude of potential techniques that could be implemented to mitigate the adverse effects of atmospheric/environmental conditions, and to optimize the effectiveness of FSO networks. Testing and selection of this broad array of techniques is a prerequisite to making FSO space segment systems and OGSs interoperable. The study discusses testing that is required to define FSO standards. The establishment of interoperable standards is complicated by the existence of a multitude of potential schemes/specifications to address each mitigation/optimization challenge; very little is yet standardized. Standardization is further complicated by the fact that the selection of a design approach which benefits one consideration often disadvantages another consideration. Each mitigation techniques must be evaluated as an element of the complete system to gain an accurate understanding of its effects on system efficacy

Comparative cost-effectiveness analyses at a Naval Air Rework Facility.

The objective of this study was to compare alternative approaches to the cost-effectiveness analysis of a technological change at the Naval Air Rework Facility, North Island, San Diego, California. Previous studies were reviewed and updated. Econometric techniques were employed to develop additional methods. Each of the methods was used to predict costs for situations both before and after the technological change. These predictions were compared as to their implications concerning the cost-effectiveness of a computerized work-in-process management information system.http://archive.org/details/comparativecoste1094516524Captain, United States ArmyApproved for public release; distribution is unlimited

The Geriatric Depression Scale: A Comprehensive Review

Reviews published information regarding the psychometric properties and utility of the English version Geriatric Depression Scale (GDS) that has accumulated over the past decade. In a number of populations, studies have assessed the reliability of the GDS using both test–retest and internal methods. The validity of the Scale was examined by comparing the results of the GDS with a number of gold standards, including clinical diagnosis and a number of other scales that purport to measure depression. The GDS has been shown to have high internal consistency and is stable over time. The Criterion validity of the GDS has also been demonstrated with most sensitivity and specificity scores remaining above 80%. However, studies examining the use of the GDS with cognitively impaired Ss produced mixed results, and preliminary studies evaluating the GDS\u27s utility with non-Caucasian Ss have been inconclusive. In general, the studies reviewed support the validity of the GDS as a useful tool for screening for depression in the elderly. Recommendations for clinical and research use of the GDS are offered