The entrainment rate for a row of turbulent jets

Entrainment rates for a row of isothermal circular air jets issuing into a quiescent environment are found by integrating velocity distributions measured by a linearized hot-wire anemometer. Jet spacing to jet diameter ratios of 2.5, 5, 10, and 20 are studied at jet Reynold's numbers ranging from 5110 to 12070. Velocity distributions are determined at regular downstream intervals at axial distances equal to 16.4 to 164 jet diameters from the jet source. The entrainment rates for the four spacing configurations vary monotonically with increasing spacing/diameter between the limiting case of the slot jet entrainment rate (where the jet spacing to diameter ratio is zero) and the circular jet entrainment rate (in which the spacing to diameter ratio is infinity)

Demand for cooking fuels in a developing country. To what extent do taste and preferences matter?

Overreliance on biomass energy, such as firewood and charcoal, for cooking in developing countries has contributed to high rates of deforestation and resulted in substantial indoor pollution which has negatively impacted the health of many individuals. However, the effectiveness of public policies aimed at encouraging households to switch to cleaner fuels, such as liquefied petroleum gas (LPG) and kerosene, hinges on the extent to which they are mentally committed to specific fuels. Using data on four cooking fuels (charcoal, firewood, LPG, and kerosene) from the Ghana living standards survey, we found strong evidence that the most preferred fuel is LPG, followed by charcoal, with kerosene the least preferred. In addition, with the exception of kerosene that has price-elastic demand, the price elasticities of demand for the fuel types examined are inelastic. This finding suggests the so-called fuel-ladder is not robust.Demand for fuel Taste and preferences Ghana

Monte Carlo Markov Chain parameter estimation in semi-analytic models of galaxy formation

We present a statistical exploration of the parameter space of the De Lucia and Blaizot version of the Munich semi-analytic (SA) model built upon the Millennium dark matter simulation. This is achieved by applying a Monte Carlo Markov Chain method to constrain the six free parameters that define the stellar and black hole mass functions at redshift zero. The model is tested against three different observational data sets, including the galaxy K-band luminosity function, B - V colours and the black hole-bulge mass relation, separately and combined, to obtain mean values, confidence limits and likelihood contours for the best-fitting model. Using each observational data set independently, we discuss how the SA model parameters affect each galaxy property and find that there are strong correlations between them. We analyse to what extent these are simply reflections of the observational constraints, or whether they can lead to improved understandings of the physics of galaxy formation. When all the observations are combined, we find reasonable agreement between the majority of the previously published parameter values and our confidence limits. However, the need to suppress dwarf galaxy formation requires the strength of the supernova feedback to be significantly higher in our best-fitting solution than in previous work. To balance this, we require the feedback to become ineffective in haloes of lower mass than before, so as to permit the formation of sufficient high-luminosity galaxies: unfortunately, this leads to an excess of galaxies around L*. Although the best fit is formally consistent with the data, there is no region of parameter space that reproduces the shape of galaxy luminosity function across the whole magnitude range. For our best fit, we present the model predictions for the bJ-band luminosity and stellar mass functions. We find a systematic disagreement between the observed mass function and the predictions from the K-band constraint, which we explain in light of recent works that suggest uncertainties of up to 0.3 dex in the mass determination from stellar population synthesis models. We discuss modifications to the SA model that might simultaneously improve the fit to the observed mass function and reduce the reliance on excessive supernova feedback in small haloes

Height Discrimination in Employment

This Article looks critically at heightism, i.e., prejudice or discrimination against a person on the basis of his or her height. Although much scholarship has focused on other forms of trait-based discrimination—most notably weight and appearance discrimination, both of which indirectly involve height as a component—little has focused on “pure” height discrimination. Nevertheless, within the past five years courts, scholars, and legislatures have increasingly tackled these non-traditional forms of discrimination. As such, this Article endeavors to fill the gap in the existing scholarship. This Article specifically focuses on heightism in the workplace, with an emphasis on prejudice against short people because of the unique disadvantages they face vis-à-vis their taller counterparts. It examines the ways that existing federal antidiscrimination laws—namely Title VII of the Civil Rights Act of 1964 and the Americans with Disabilities Act of 1990—do and do not protect against height-based prejudice in the workplace. Moreover, after briefly examining state and local remedies for height discrimination, including state antidiscrimination laws, this Article considers but ultimately rejects enacting a federal law that would flatly prohibit all height-based employment decisions. Although a comprehensive prohibition would be easiest to administer, such a prohibition would prove both gratuitous and unwise. Instead, this Article recommends modest changes to federal regulations and increased state and local enforcement

Butterfly abundance in a warming climate: patterns in space and time are not congruent

We present a model of butterfly abundance on transects in England. The model indicates a significant role for climate, but the direction of association is counter to expectation: butterfly population density is higher on sites with a cooler climate. However, the effect is highly heterogeneous, with one in five species displaying a net positive association. We use this model to project the population-level effects of climate warming for the year 2080, using a medium emissions scenario. The results suggest that most populations and species will decline markedly, but that the total number of butterflies will increase as communities become dominated by a few common species. In particular, Maniola jurtina is predicted to make up nearly half of all butterflies on UK Butterfly Monitoring Scheme (UKBMS) transects by 2080. These results contradict the accepted wisdom that most insect populations will grow as the climate becomes warmer. Indeed, our predictions contrast strongly with those derived from inter-annual variation in abundance, emphasizing that we lack a mechanistic understanding about the factors driving butterfly population dynamics over large spatial and temporal scales. Our study underscores the difficulty of predicting future population trends and reveals the naivety of simple space-for-time substitutions, which our projections share with species distribution modelling

Alien Registration- Bubar, Isaac B. (Limestone, Aroostook County)

https://digitalmaine.com/alien_docs/35082/thumbnail.jp

Atmospheric Impact on Long Pulse Laser Detection and Ranging (LADAR) Systems

For conventional imaging systems, GEO space objects cannot be resolved due to their 40 Mm distance. There exists a strong need to obtain high resolution images of GEO objects and to accomplish this task, investigation into the suitability of ISAL is currently underway. A critical component in determining this suitability is to accurately model the atmospheric impacts on LADAR pulses. Conventional knowledge says that while the atmosphere churns, wind is the predominant cause of temporal evolution which simplifies all modeling and simulation into the frozen flow hypothesis. The concern is that the frozen flow hypothesis based phase screen generation techniques fail to accurately predict the temporal development of optical phase. This thesis proposes a new approach and provides a detailed derivation of a new temporally evolving Zernike polynomial based atmospheric phase screen generation model. This new model is experimentally verified, and utilized to analyze atmospheric impacts on mixing efficiencies. It is shown that this new turbulent flow model more accurately predicts mixing efficiency than that of the basic frozen flow approximation

Electronic Banking Services in Nigeria: Some Determinants and Opportunities for Households' Financial Inclusion

Economic transactions in many of the countries in Africa are still largely cash-based and many of these transactions are costly, inefficient, time consuming and sometimes risky because of the security situation in most countries in the continent. In fact, finality of payment is not always guaranteed because of potential counterfeits and the lack of financial discipline when cheques or other paper-based means of payment are used. The introduction of electronic banking services into the Nigerian banking sector has brought some respite considering the number of people now using electronic platforms such as the Automated Teller Machines (ATM), mobile phones, internet and bank websites instead of the conventional over the counter method used by most people. The result presented in here is based on secondary data consisting of 6002 respondents collected by The Financial Inclusion Insights Program, InterMedia. A descriptive analysis of data showed that the North-central (35%) and South-west (33%) geopolitical zones of the country had the highest as over one-third of the residents harnessed internet as the platform for their banking services. Meanwhile on the determinants of using electronic banking services, the result of the tobit model employed revealed age, gender, education status, and ownership of mobile phones as positive enablers and poverty status, distance to banking services and marital status as hiccups to using electronic banking services. The study therefore recommends welfare enhancement through provision of infrastructural facilities to ease access banking services, Also capacity building of respondents through education should be intensified since most of the people using these electronic platforms are those with a minimum of secondary education