Swarming and Mating in \u3ci\u3eAedes Provocans\u3c/i\u3e (Diptera: Culicidae)

Male Aedes provocans formed canopy-level linear swarms in association with prominent trees along hedgerows or convex prominences along woodlot margins. Males oriented along the east-west or north-south axis of the swarm site and flew continuously in alternating directions along the longitudinal axis of the swarm. Swarming began shortly before (mean=-0.78 crep) and ended after sunset (mean=0.81 crep). The time of onset of swarming was more variable than the time of cessation; on 3 of 5 occasions, swarming stopped abruptly at 0.94 crep, about 2 minutes before the end of civil twilight. Swarming began 4 d after the onset of emergence of the adults and persisted for 3 weeks, but copulations were observed for only the first 6 d. In-flight mating always took place after sunset, many minutes after the onset of swarming. On average, copulation lasted 9.9 s

The use of graphics in the design of the human-telerobot interface

The Man-Systems Telerobotics Laboratory (MSTL) of NASA's Johnson Space Center employs computer graphics tools in their design and evaluation of the Flight Telerobotic Servicer (FTS) human/telerobot interface on the Shuttle and on the Space Station. It has been determined by the MSTL that the use of computer graphics can promote more expedient and less costly design endeavors. Several specific examples of computer graphics applied to the FTS user interface by the MSTL are described

Ron\u27s Home

He must be home. His laundry is here, Mrs. Curtis said as she stepped in the back door and stomped the snow from her black clasp boots. She was looking at her son\u27s suitcase and the multi-colored blizzard of T-shirts and blue jeans crawling out from the washing machine...

Movements and Habitats of Brood-Rearing Wood Ducks On A Prairie River

Radio telemetry and brood surveys were used to evaluate wood duck (Aix sponsa) brood habitat and movements along 40 km of the Big Sioux River in eastern South Dakota during 1979-81. Most of the oxbows and nearby wetlands in the study area contained water in 1979-80, but drought dried all but 2 of the 33 oxbows in 1981. Fourteen brood hens were radio monitored. In 1980, 4 hens utilized oxbows, 1 hen utilized the river, and 2 hens used other habitats for brood rearing. In 1981, 4 hens utilized oxbows, 2 hens utilized the river, and 1 hen utilized the outlet of a nearby lake for brood rearing. The longest brood movements generally occurred during the 2 days following nest exodus. Hens apparently had initial brood-rearing sites selected before nest exodus. In 1979, no wood duck broods were found on 43 upland wetlands located within 0.8 km of the river, 0.46 broods/km were seen on oxbows, and 0.05 broods/km and 1.67 broods/km were seen on the river. In 1980 and 1981, respectively, 0.63 broods/km and 1.67 broods/km were seen on oxbows, and 0.15 broods/km and 0.27 broods/km were seen on the river. Oxbows appeared to be preferred brood habitat, while the river served primarily as a travel route between oxbows. The lentic oxbow waters contain abundant emergent and submergent vegetation and support abundant invertebrate populations, thereby meeting brood requirements for food and cover

Human Selection and Digitized Archival Collections: an Exploratory Research Project About Choice of Archival Materials Digitized for Online Public Availability

Our collective memory, the history that is cultivated through reflection, documentation, and consensus of historical data, is predicated upon the citizenry having access to the historical materials that society has created. Digitization has enabled greater public access to those materials. However, are items being scanned or digitally photographed to create surrogates that are then not made available to the world? The impetus for this study is to delve into whether or not intentional or unintentional personal choices play a role in determining which items archivists transform into digital surrogates; both in the decision of what to digitize and what to make available to the public on the World Wide Web. When one archival collection is prioritized over another or when it is not possible to digitize an entire collection, what rationale is used to determine which items will be digitized and published online? Do intentional or unintentional personal choices come into play in the decision-making? To answer these questions, four case studies were conducted, involving the random sampling of online collections and concomitant interviews of archivists. The purpose of this study is to enhance archivists’ understanding of the reasons that guide the digitization decision-making process. Through such understanding, archivists can be more proactive in the decision-making process to realize the benefit of digitizing and publishing archival materials that ultimately affect collective memory. The findings of this research revealed that in the case of the four institutions assessed, archivists do use personal choice to determine which materials within an archive are digitized

General Equilibrium Benefit Transfers for Spatial Externalities: Revisiting EPA's Prospective Analysis

Environmental policy analyses increasingly require the evaluation of benefits from large changes in spatially differentiated public goods. Such changes are likely to induce general equilibrium effects through changes in household expenditures and local migration, yet current practice "transfers" constant marginal values for even the largest changes. Moreover, it ignores important distributional effects of policy. This paper demonstrates that recently developed locational equilibrium models can provide transferable general equilibrium benefit measures. Our results suggest that taking account of the potential for adjustment and household heterogeneity is important. Applying benefits estimated from this method to the effect of the Clean Air Act amendments in Los Angeles, we find that the estimated annual general equilibrium benefits in 2000 and 2010 are dramatically different by income group and location. The gains range from $33 to about$2,400 per household. These differences arise from variations in the air quality conditions, income, and the effects of general equilibrium price adjustment.air quality, clean air act, non-market valuation, Tiebout model

Why Do School District Budget Referenda Fail?

[Excerpt] Public elementary and secondary education is financed in many states at least partially at the local level and school district budgets in many states are determined by voter referenda. To date, however, there have been no studies that sought to explain why the proportion of school district budget proposals in a state that are approved by voters in referenda varies over time. Similarly no research has used panel data on school districts to test whether budget referenda failures are concentrated in a small number of school districts within a state and whether the failure of a budget referendum in a school district in one year influences the likelihood that voters in the district subsequently defeat a budget referendum in the next year. Our paper uses data from school budget votes in New York State to answer these questions

Telepresence for space: The state of the concept

The purpose here is to examine the concept of telepresence critically. To accomplish this goal, first, the assumptions that underlie telepresence and its applications are examined, and second, the issues raised by that examination are discussed. Also, these assumptions and issues are used as a means of shifting the focus in telepresence from development to user-based research. The most basic assumption of telepresence is that the information being provided to the human must be displayed in a natural fashion, i.e., the information should be displayed to the same human sensory modalities, and in the same fashion, as if the person where actually at the remote site. A further fundamental assumption for the functional use of telepresence is that a sense of being present in the work environment will produce superior performance. In other words, that sense of being there would allow the human operator of a distant machine to take greater advantage of his or her considerable perceptual, cognitive, and motor capabilities in the performance of a task than would more limited task-related feedback. Finally, a third fundamental assumption of functional telepresence is that the distant machine under the operator's control must substantially resemble a human in dexterity