44,668 research outputs found

    Predicting the probability of conversion to natural gas in the Fairbanks Northstar Borough

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    Thesis (M.S.) University of Alaska Fairbanks, 2017In 2013 a phone survey was conducted for Northern Economics Inc. by Ivan Moore Research Group, with the goal of determining the willingness of households in the Fairbanks North Star Borough to convert their residence to natural gas. This paper provides an analysis of prior household discrete choice experiments involving energy usage. Probit regression is used to determine the probability of conversion given different levels of household income, payback period, cost of conversion, and annual saving associated with conversion, in addition to these variables three statistically significant attitudinal variables are included. Marginal effects and elasticities are presented and interpreted. Findings are congruent with past research and indicate that to maximize the conversion rate of households, the cost of conversion needs to be minimized or, if possible, subsidized and the annual level of saving maximized. Initial results suggest conversion cost is weighed more heavily than annual savings

    Parasitism of \u3ci\u3eUrophora Affinis\u3c/i\u3e (Diptera: Tephritidae) by \u3ci\u3eAprostocetus\u3c/i\u3e Sp. (Hymenoptera: Eulophidae) in Michigan

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    (excerpt) Urophora affinis Frfld. and U. quadrifasciata (Meig.) (Diptera: Tephriti- dae) are Eurasian gallicolous fruit flies introduced to North America in 1972 as biological control agents for Centaurea biebersteinii DC (spotted knapweed, Asteraceae, = C. maculosa auct. non Lam.) (Harris 1980). Through natural dispersal and numerous introductions, both Urophora species have become distributed throughout the introduced range of C. biebersteinii (Foote et al. 1993, Lang et al. 1997, Mays and Kok 2003)

    Water Crisis in Vietnam

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    • Immediately after the Vietnam War ended in 1975, Vietnam experienced economic turmoil and famine as the roots of industrialization began to grip the nation. • In 1986, the government declared a rapid transition from a planned to a market economy would take hold. The ensuing change caused further increased industrial development and a subsequent growth of the emerging market economy. 1 • To this day, Vietnam’s GDP is rising yearly at a rapid rate. • For this reason, much of Vietnam has been developed in a relatively short amount of time (since the end of the war) but much of it has lagged behind, including the infrastructure including water pipes and water sanitation plants. This lag has caused limited access to sanitized water in both rural and urban areas. • Despite an overall adequate water access for Vietnamese citizens, the sanitation of supplied water has not improved as markedly as the country as a whole. • Sanitation has increased from 37% in 1990 to 75% in 2011 as defined by the JMP’s sanitation standards. Here, sanitation is defined as the distance between a water supply and human excretion.2 • Although Vietnam’s water has been made safer over the past few decades, it is largely undrinkable. • A 2009 study done by scientists at the Vietnam Institute of Biotechnology concluded that ammonia levels in Vietnam’s waters range from an average of 6-18 times higher than an acceptable level. 3 Furthermore, arsenic levels range from 2-3 times higher than an acceptable level.https://jdc.jefferson.edu/cwicposters/1025/thumbnail.jp

    Shield weight optimization using Monte Carlo transport calculations

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    Outlines are given of the theory used in FASTER-3 Monte Carlo computer program for the transport of neutrons and gamma rays in complex geometries. The code has the additional capability of calculating the minimum weight layered unit shield configuration which will meet a specified dose rate constraint. It includes the treatment of geometric regions bounded by quadratic and quardric surfaces with multiple radiation sources which have a specified space, angle, and energy dependence. The program calculates, using importance sampling, the resulting number and energy fluxes at specified point, surface, and volume detectors. Results are presented for sample problems involving primary neutron and both primary and secondary photon transport in a spherical reactor shield configuration. These results include the optimization of the shield configuration

    How Does Labor Mobility Affect Income Convergence?

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    The neoclassical growth model is extended to allow for mobile labor. Following a negative shock to a small economy's capital stock, capital and labor frictions effect an equilibrium transition path during which wages remain below their steady-state level. Outmigration directly contributes to faster income convergence but also creates a disincentive for gross capital formation. The net result is that across a wide range of calibrations, the speed of income convergence is relatively insensitive to the degree of labor mobility.

    Radiation protection for manned space activities

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    The Earth's natural radiation environment poses a hazard to manned space activities directly through biological effects and indirectly through effects on materials and electronics. The following standard practices are indicated that address: (1) environment models for all radiation species including uncertainties and temporal variations; (2) upper bound and nominal quality factors for biological radiation effects that include dose, dose rate, critical organ, and linear energy transfer variations; (3) particle transport and shielding methodology including system and man modeling and uncertainty analysis; (4) mission planning that includes active dosimetry, minimizes exposure during extravehicular activities, subjects every mission to a radiation review, and specifies operational procedures for forecasting, recognizing, and dealing with large solar flaes
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