REVIEW: AMPHIBIAN SURVEYS IN FORESTS AND WOODLANDS

Amphibian surveys provide information on the distribution, abundance and habitat requirements of species, and the environmental variables that control diversity. Such information is needed for effective conservation planning and management of forests and woodlands, including monitoring of amphibian populations in a period of apparent global decline. Amphibian surveys can be time-consuming and expensive, and many issues must be addressed to maximize the reliability of the resulting data. Sampling techniques that are effective in one region or habitat type may be less so in another, and a preliminary study comparing different techniques before undertaking a survey may be necessary. Data collected in poorly designed surveys can be unsuitable for statistical analysis, and may sometimes present a misleading picture of the distribution, abundance and habitat requirements of amphibian species. This review examines issues of survey design, assesses past amphibian surveys in forest and woodland habitats, and provides recommendations for planning an amphibian survey. Firstly, the study area and survey aims should be identifi ed, and proposed sampling techniques assessed using relevant literature or a pilot study. Ethical issues associated with proposed sampling techniques should also be considered. The number, size and arrangement of the survey units (e.g. plots, sites or transects) should be sufficient to address the survey aims. The survey units should be systematically surveyed several times with appropriate sampling techniques

Effects of visual and motion simulation cueing systems on pilot performance during takeoffs with engine failures

Data are presented that show the effects of visual and motion during cueing on pilot performance during takeoffs with engine failures. Four groups of USAF pilots flew a simulated KC-135 using four different cueing systems. The most basic of these systems was of the instrument-only type. Visual scene simulation and/or motion simulation was added to produce the other systems. Learning curves, mean performance, and subjective data are examined. The results show that the addition of visual cueing results in significant improvement in pilot performance, but the combined use of visual and motion cueing results in far better performance

Extensions of Effective Medium Theory of Transport in Disordered Systems

Effective medium theory of transport in disordered systems, whose basis is the replacement of spatial disorder by temporal memory, is extended in several practical directions. Restricting attention to a 1-dimensional system with bond disorder for specificity, a transformation procedure is developed to deduce, from given distribution functions characterizing the system disorder, explicit expressions for the memory functions. It is shown how to use the memory functions in the Lapace domain forms in which they first appear, and in the time domain forms which are obtained via numerical inversion algorithms, to address time evolution of the system beyond the asymptotic domain of large times normally treated. An analytic but approximate procedure is provided to obtain the memories, in addition to the inversion algorithm. Good agreement of effective medium theory predictions with numerically computed exact results is found for all time ranges for the distributions used except near the percolation limit as expected. The use of ensemble averages is studied for normal as well as correlation observables. The effect of size on effective mediumtheory is explored and it is shown that, even in the asymptotic limit, finite size corrections develop to the well known harmonic mean prescription for finding the effective rate. A percolation threshold is shown to arise even in 1-d for finite (but not infinite) systems at a concentration of broken bonds related to the system size. Spatially long range transfer rates are shown to emerge naturally as a consequence of the replacement of spatial disorder by temporal memories, in spite of the fact that the original rates possess nearest neighbor character. Pausing time distributions in continuous time random walks corresponding to the effective medium memories are calculated.Comment: 15 pages, 11 figure

Random Walk Access Times on Partially-Disordered Complex Networks: an Effective Medium Theory

An analytic effective medium theory is constructed to study the mean access times for random walks on hybrid disordered structures formed by embedding complex networks into regular lattices, considering transition rates $F$ that are different for steps across lattice bonds from the rates $f$ across network shortcuts. The theory is developed for structures with arbitrary shortcut distributions and applied to a class of partially-disordered traversal enhanced networks in which shortcuts of fixed length are distributed randomly with finite probability. Numerical simulations are found to be in excellent agreement with predictions of the effective medium theory on all aspects addressed by the latter. Access times for random walks on these partially disordered structures are compared to those on small-world networks, which on average appear to provide the most effective means of decreasing access times uniformly across the network.Comment: 12 pages, 8 figures; added new results and discussion; added appendix on numerical procedures. To appear in PR

Development, implementation and evaluation of satellite-aided agricultural monitoring systems

Research supporting the use of remote sensing for inventory and assessment of agricultural commodities is summarized. Three task areas are described: (1) corn and soybean crop spectral/temporal signature characterization; (2) efficient area estimation technology development; and (3) advanced satellite and sensor system definition. Studies include an assessment of alternative green measures from MSS variables; the evaluation of alternative methods for identifying, labeling or classification targets in an automobile procedural context; a comparison of MSS, the advanced very high resolution radiometer and the coastal zone color scanner, as well as a critical assessment of thematic mapper dimensionally and spectral structure

Determining Educational Achievement

This is a single subject case study using the method of purposive sampling of a student with Cerebral Palsy, Attention Deficit Hyperactivity Disorder and Speech Impairment. The subject was given the Woodcock Reading Mastery, KeyMath, and Kaufman Test of Education Achievement assessments due to noticeable poor academic performance. Students with Cerebral Palsy often have cognitive deficits. The reason for this investigation was to determine subject’s strengths and weaknesses. By determining his strengths and weaknesses it would be easier to focus instruction and provide support on areas where my subject has the most difficulty. Also, administering multiple achievement tests would determine if my subject’s low performance was due to difficulties in one subject area (such as reading) that was effecting his performance across the curriculum. The purpose for this study was to obtain data that could be reviewed used to provide the instructional support and planning needed to improve his educational achievement. We found that our hypothesis was true; The results showed that he performedsignificantly below average in overall achievement

Effects of disorder in location and size of fence barriers on molecular motion in cell membranes

The effect of disorder in the energetic heights and in the physical locations of fence barriers encountered by transmembrane molecules such as proteins and lipids in their motion in cell membranes is studied theoretically. The investigation takes as its starting point a recent analysis of a periodic system with constant distances between barriers and constant values of barrier heights, and employs effective medium theory to treat the disorder. The calculations make possible, in principle, the extraction of confinement parameters such as mean compartment sizes and mean intercompartmental transition rates from experimentally reported published observations. The analysis should be helpful both as an unusual application of effective medium theory and as an investigation of observed molecular movements in cell membranes.Comment: 9 pages, 5 figure

The design of a petabyte archive and distribution system for the NASA ECS project

The NASA EOS Data and Information System (EOSDIS) Core System (ECS) will contain one of the largest data management systems ever built - the ECS Science and Data Processing System (SDPS). SDPS is designed to support long term Global Change Research by acquiring, producing, and storing earth science data, and by providing efficient means for accessing and manipulating that data. The first two releases of SDPS, Release A and Release B, will be operational in 1997 and 1998, respectively. Release B will be deployed at eight Distributed Active Archiving Centers (DAAC's). Individual DAAC's will archive different collections of earth science data, and will vary in archive capacity. The storage and management of these data collections is the responsibility of the SDPS Data Server subsystem. It is anticipated that by the year 2001, the Data Server subsystem at the Goddard DAAC must support a near-line data storage capacity of one petabyte. The development of SDPS is a system integration effort in which COTS products will be used in favor of custom components in very possible way. Some software and hardware capabilities required to meet ECS data volume and storage management requirements beyond 1999 are not yet supported by available COTS products. The ECS project will not undertake major custom development efforts to provide these capabilities. Instead, SDPS and its Data Server subsystem are designed to support initial implementations with current products, and provide an evolutionary framework that facilitates the introduction of advanced COTS products as they become available. This paper provides a high-level description of the Data Server subsystem design from a COTS integration standpoint, and discussed some of the major issues driving the design. The paper focuses on features of the design that will make the system scalable and adaptable to changing technologies

Diversity in Adult Education: Lessons learned from a Master of Education Program in Studies of Lifelong Learning with a Focus on Africentric Leadership

n this paper we explore the lifelong learning experiences of students who graduated from a unique two year Master of Education (M.Ed) cohort program in studies of lifelong learning with a focus on Africentric Leadership. We conducted in-depth interviews with 13 graduates of the program to explore the role Africentricity and Critical Race Theory play in adult education in higher education institutions. Our findings draw attention to several key points about adult education in post secondary education institutions that have the potential to transform the culture of adult education