Atmospheric waves and the nature of buoyancy turbulence in the context of the waves VS 2D-turbulence debate

The problem of how to empirically distinguish between velocity fluctuations due to turbulence and those due to atmospheric waves is addressed. The physical differences between waves and turbulence are reviewed. New theoretical ideas on the subject of bouyancy range turbulence are presented. A unique scale K sub B is given that allows one to differentiate between waves and turbulence for the special case of theta = 0 (i.e., horizontal propagating waves)

A proposed experimental test to distinguish waves from 2-D turbulence

A theory of buoyancy range turbulence that leads to a unique scale, K sub B, that allows one to differentiate between waves and turbulence for the special case of theta = 0 (i.e., horizontally propagating waves) is discussed. The theory does not seem to lead to a practical empirical distinction for the general situation. This is due to the fact that, as theta is increased, one has the ever-increasing presence of BRT for longer wavelengths. The fact that the numerical values of epsilon prime are not yet available compounds the difficulty. In addition, it does not appear possible to encompass true 2-D turbulence in the theory. We are thus driven to a test which circumvents all these difficulties. A proposed test is based on the idea that waves are coherent and propagate, while in turbulence we have the opposite situation. In particular, the test is suggested by the following quotation from MULLER (1984), on the nature of such turbulence: The turbulence in each horizontal plane is independent from the turbulence in the other planes. If this statement were to be taken literally, it would imply that the temporal coherence between horizontal speeds, separated only in altitude, would be zero. Any vertical separation would be forced to take into account the effects of viscosity: that is to say, a specific finite vertical separation would be needed to destroy coherence. In order to estimate this distance, L, one can use L = C(v/S) (1/2) were v is the kinematic viscosity, S is the shear scale, and C is a constant of order unity

Consumer Choice Model of Mobile Banking

Research in the adoption of mobile banking (m-banking) has not offered a comprehensive explanation of low demand for the service. This paper proposes a theoretical model to account for the explanations of the consumer’s choice whether to adopt m-banking or not. The model underlies the cognitive processes of reasoning, referencing and contextualising, as postulated in the behavioural decision making. The proposed theoretical framework is based on a review of literature from services marketing, behavioural economics and information systems

On the Eneström-Kakeya Theorem

AbstractA classical result of Eneström and Kakeya (If an ≥ an−1 ≥ ··· ≥ a0 > 0, then, for |z| > 1, ∑nk=0akzk ≠ 0) is extended to polynomials whose coefficients satisfy the condition tnan ≤ tn−1an−1 ≤ ··· ≤ tλ+1aλ+1 ≤ tλaλ ≥ tλ−1aλ−1 ≥ ··· ≥ ta1 ≥ a0, for some t > 0 and 0 < λ ≤ n

Impacts of technological interventions on fish production and biodiversity of seasonal floodplains in Bangladesh

The Community-based Fish Culture in Seasonal Floodplains and Irrigation Systems (CBFC) project is a five year research project supported by the Challenge Program on Water and Food (CPWF), with the aim of increasing productivity of seasonally occurring water bodies through aquaculture. The project has been implemented in Bangladesh, Cambodia, China, Mali and Vietnam, where technical and institutional options for community based aquaculture have been tested. The project began in 2005 and was completed in March 2010. The objective of the study was to determine the impacts of technological interventions in the floodplains on fish yield and biodiversity benefiting the poor fisher folk and other community people. Technological interventions for fish culture in the floodplains included (a) the installation of low-cost large meshed bamboo fencing at water inlet and outlet points, and setting of ring culverts for maintaining suitable levels of water for fish culture without hampering the production of rice in the upland areas of the floodplains (b) stocking of larger fingerlings at suitable stocking densities of endemic (rohu, catla, mrigal) and exotic (silver carp, bighead carp, common carp/mirror carp) species at 31-48 kg/ha (c) post stocking management; use of extra fencing during over flooding and mobile guarding using boats (d) harvesting management; regulations in harvest for certain period, use of multiple harvesting techniques. These interventions were carried out through CB participation with initial technological and financial support from the Challenge Program Project (CP35).Flood plains, Freshwater aquaculture

Environmental factors associated with the distribution of visceral leishmaniasis in endemic areas of Bangladesh: Modeling the ecological niche

Background: Visceral leishmaniasis (VL) is a parasitic infection (also called kala-azar in South Asia) caused by Leishmania donovani that is a considerable threat to public health in the Indian subcontinent, including densely populated Bangladesh. The disease seriously affects the poorest subset of the population in the subcontinent. Despite the fact that the incidence of VL results in significant morbidity and mortality, its environmental determinants are relatively poorly understood, especially in Bangladesh. In this study, we have extracted a number of environmental variables obtained from a range of sources, along with human VL cases collected through several field visits, to model the distribution of disease which may then be used as a surrogate for determining the distribution of Phlebotomus argentipes vector, in hyperendemic and endemic areas of Mymensingh and Gazipur districts in Bangladesh. The analysis was carried out within an ecological niche model (ENM) framework using a maxent to explore the ecological requirements of the disease. Results: The results suggest that VL in the study area can be predicted by precipitation during the warmest quarter of the year, land surface temperature (LST), and normalized difference water index (NDWI). As P. argentipes is the single proven vector of L. donovani in the study area, its distribution could reasonably be determined by the same environmental variables. The analysis further showed that the majority of VL cases were located in mauzas where the estimated probability of the disease occurrence was high. This may reflect the potential distribution of the disease and consequently P. argentipes in the study area. Conclusions: The results of this study are expected to have important implications, particularly in vector control strategies and management of risk associated with this disease. Public health officials can use the results to prioritize their visits in specific areas. Further, the findings can be used as a baseline to model how the distribution of the disease caused by P. argentipes might change in the event of climatic and environmental changes that resulted from increased anthropogenic activities in Bangladesh and elsewhere

Influences of Moral Virtues and Confucianism on E-Business Entrepreneurs: An Exploratory Study in Singapore

Many small e-businesses targeting Internet consumer markets operate in an increasingly competitive environment. The struggle faced by business owners striving to stay sustainable while abiding by moral principles constitutes a critical issue in business ethics. The purpose of this study is to explore the influences of moral virtues and Confucian ethics on small ebusiness entrepreneurs and their practice. Through in-depth interviews, fourteen online sellers in Singapore shared seven principles which impact the ways they mange a business, namely integrity, fairness, justice, reciprocity, generosity, authenticity and accountability. Not denying the need for business profitability, these entrepreneurs emphasize the importance of adopting moral principles towards fostering long-lasting relationships with their customers. Although not explicitly mentioned, some Confucian values such as reciprocity, righteousness, benevolence and social relationship still emerged, implying the presence of scant influence of Confucian ethics on Singapore Chinese e-sellers