Research in millimeter wave techniques

A model 180-GHz radiometer, employing a Cassegrain feed geometry with a parabolic main reflector and a subreflector fed by a corrugated conical horn, was constructed and tested. An absorber-coated chopper is used to modulate the signal, which is down-converted in a cross-guide harmonic mixer. A 100-GHz source was used to evaluate mixer performance and to optimize system parameters. Preliminary results indicate a noise figure of approximately 20 db is being achieved. Preliminary design studies and on-going research plans are discussed

A millimeter wave propagation experiment from the ATS-E spacecraft

Millimeter wave propagation experiment from Applications Technology Satellite-

Analysis of Networks in a College of Agriculture Course

Technology advances occur almost daily and how they share information is constantly evolving. Educators must understand how their students prefer communicating especially relating to coursework. By mapping social networks present in courses, it may allow educators to determine how students prefer to communicate and also determine if there are constant identities that are stable throughout the semester (Edgar, Amaral, and Edgar, 2010). For the participants in this study, contacts between students increased from the initial to the final assessment of the semester. Face-to-face communication was the preferred method of communication followed by text messaging and Facebook. Communicating for social reasons was most cited with planning and venting closely being the reasons cited for contact after social. Overall, venting increased substantially as did planning throughout the course of the semester but social kept somewhat constant. No perpetual key players were identified through this study with the exception of one from the middle to the end iteration which disagrees with previous research

Urban-Suburban Prairie Dog Management: Opportunities and Challenges

The historic range of the black-tailed prairie dog has undergone dramatic declines in the last century, prompting concern about the species\u27 long-term viability. While considered a pest by many, others believe that the species is a keystone element of prairie ecosystems. Urban-suburban land managers are challenged with preserving colonies of prairie dogs on public lands while dealing with many conflicting interests, social costs, and risks. We review the management plans that municipalities have designed to reduce conflicts by using public input, zoned management, and a variety of management techniques. Areas of difficulty and research needs are also discussed

Usability of Nomadic User Interfaces

Abstract. During the last decade, a number of research activities have been performed to enable user interfaces and the underlying user activities to be migrated from one device to another. We call this “Nomadic User Interfaces”. The primary goal of these research activities has been to develop the technologies to enable this. However, not much is known about the usability aspects of Nomadic User Interfaces. In this paper we present the results of three different user tests that we conducted to investigate the usefulness and the usability issues of several prototype Nomadic User Interface systems that we developed

Fecundity of Wild Northern Bobwhite Hens Under Hatchery Conditions

We describe egg production by 88 pairs of randomly selected, mature, wild-caught northern bobwhite (Colinus virginianus) hens housed under optimal conditions of food, water, climate, and a 17-hr photoperiod in a hatchery. We collected eggs daily using an 18-day period to differentiate between clutches. Hens continuously laid eggs until ceasing production. We evaluated number of eggs laid by each hen individually and hens collectively including total number, number/clutch, number/day, hatching success, and egg mass. Eighty-six hens produced 5,888 eggs. Number of eggs produced by individual hens ranged from 0 to 172 over ~ 200 days. Mean number of eggs laid/hen/day was 0.86. Clutch size ranged from 0 (n 1⁄4 2) to 12 (n 1⁄4 1). Mean number of eggs/clutch was 8.57. There was a strong correlation between clutch size and number of clutches. Some hens demonstrated continuous production of several large clutches. Hatching success of 5,793 eggs included for analysis was 61.6% (3,571 hatched, 2,222 failed to hatch). Hatched eggs had a greater mean mass compared to those that did not hatch

Macroeconometric Modelling with a Global Perspective

This paper provides a synthesis and further development of a global modelling approach introduced in Pesaran, Schuermann and Weiner (2004), where country specific models in the form of VARX* structures are estimated relating a vector of domestic variables to their foreign counterparts and then consistently combined to form a Global VAR (GVAR). It is shown that VARX* models can be derived as the solution to a dynamic stochastic general equilibrium (DSGE) model where over-identifying long-run theoretical relations can be tested and imposed if acceptable. Similarly, short-run over-identifying theoretical restrictions can be tested and imposed if accepted. The assumption of the weak exogeneity of the foreign variables for the long-run parameters can be tested, where foreign variables can be interpreted as proxies for global factors. Rather than using deviations from ad hoc statistical trends, the equilibrium values of the variables reflecting the long-run theory embodied in the model can be calculated

RAPTOR USE OF ARTIFICIAL PERCHES AT NATURAL AREAS, CITY OF FORT COLLINS, COLORADO

The black-tailed prairie dog (Cynomys ludovicianus) remains a critical element of the prairie ecosystem even though its numbers and occupied range have declined dramatically since the arrival of Europeans in North America (Antol in et al. 2002). Prairie dog colonies are used by many species of wildlife and help maintain high levels of biodiversity (Kotliar et al. 1999). In the urban-suburban setting, the occurrence of prairie dog colonies also provides opportunities for wildlife viewing and environmental education. Unfortunately, prairie dogs also can come into conflict with humans, especially in the urban-suburban setting, where they cause vegetation and property damage, and pose a health threat attributable to periodic plague (Yersinia pestis) outbreaks (Witmer et al. 2003). Efforts to reduce conflicts can involve colony relocation or management so that the prairie dog population and occupied area does not increase (e.g., lethal or non-lethal removal, construction of physical barriers around the colony; Witmer et al. 2003). frtificial perches, placed at prairie dog colonies, can attract raptors, while providing for public viewing of raptors. The artificial perches, if strategically placed, also might increase predation on prairie dogs, slowing the increase in the size of the colony (Witmer et al. 2003). This approach has been used in other settings in an attempt to reduce rodent populations or damage, but most researchers reported little success in rodent control (e.g., Howard et al. 1985, Askham 1990, Moore and Van Vuren 1998, Wolff et al. 1999). A few researchers, however, reported that increased use of artificial perches might help reduce rodent numbers and damage (e.g., Kay et al. 1994, Mulner 2000, Hafidzi and Mohd 2003). In our region, this management practice might be especially effective given the paucity of trees (i.e., natural perches) in the shortgrass prairie outside riparian systems (Weaver et al. 1996). The objective of this study was to document the use of artificial perches by raptors and the food habits of these raptors within the city limits of Fort Collins, Colorado