1,301 research outputs found
The use of a water quality model to evaluate the impacts of combined sewer overflows on the lower Hudson River
CSO discharges have long been recognized as a significant source of water pollution. While many sources of water pollution have been controlled over the past 20 years, CSOs continue to be a main environmental concern in several areas, especially in old cities. In the past, most CSO research focused on the CSO control processes, including floatables and suspended solids removal. Few studies have been conducted in the area of the impacts of CSO discharge on the receiving water quality. To achieve this purpose, a powerful water-modeling tool, WASP 6.1, is utilized in this study. The Lower Hudson River is selected as a case study. Data are collected from the US EPA, USGS, NYC DEP, and NJ DEP. After calibration, the receiving water quality model can be used to study the impacts of CSO with a series of scenarios, which include the major factors that would affect the water quality of the receiving water. DO, BOD, ammonia, fecal coliform, and mercury are the reference pollutants discussed in this study. The simulation results are able to predict the effect of various CSO abatement alternatives on water quality and to be used in the water quality management and planning processes
Modeling Chinese post-90\u272 tourism loyalty to the ex-rival state using the perceived value approach
Purpose – A recent trend in tourism research involves the study of independent Chinese tourists.
Yet while post-90s or Generation Z (i.e., born in the 1990s) comprises an important share of nondomestic visitors to Taiwan and other tourist destinations, this segment of the tourist population is currently under-analyzed. As a pioneering piece of research in this area, this survey attempts to understand Chinese tourists of this cohort visiting the long-divided state.
Design – This research incorporates the social dimension of perceived value in the ordinarily employed perceived-value model to better understand why Chinese post-90s would like to recommend Taiwan.
Methodology – This study samples Chinese students from 12 universities located in the northern, central, southern, and western regions of Taiwan. They were investigated with the selfadministered survey which is composed of five constructs, for a total of 17 questions. Structural equation modeling was employed to analyze the collected data and testify the hypotheses.
Findings – The finding provides insights in the specific tourism behaviors of this cohort and how they are found distinct from their predecessors. The emotional dimension of the post-90s’ tourismrelated perceived value is a strong determinant of their loyalty to Taiwan as a tourist destination. The prior-rival situation between both sides of the Taiwan Strait might signify that social dimension significantly predict their loyalty, through the mediator of satisfaction.
Originality – This research provides important information for tourism businesses regarding place management and marketing strategies, enabling them to receive this new generation of Chinese customers
Rich or alive? Political (in)stability, political leader selection and economic growth
We develop a model that studies the incentives of the ruling elite regarding the selection of the political leader. We show that it is optimal for the ruling elite to choose leaders with more military experience in a politically unstable regime while more educated leaders are preferred in politically stable regimes. Using a dataset that includes 1569 national leaders from 177 countries over the period 1946-2011, we find empirical evidence that political stability contributes to the selection of more educated leaders, while the reverse holds for leaders with high military ranks. The empirical findings are robust to different subsamples, various proxies for educational and military attainment, and different measures for political stability. Our results suggest that leader selection is another reason why political instability is harmful for economic growth
EXPERIENCE-ORIENTED MODEL OF BUDGET ALLOCATION AND COST CONTROL FOR ENGINEERING CONSULTING PROJECTS
This paper presents an experience-oriented model of budget allocation and cost control for engineering consulting projects. The proposed model comprised two modules: a work item module and a work duration module. Regarding the work item module, a project manager employed the analytic hierarchy process (AHP) to determine the budget percentage allocated to each work item. Regarding the work duration module, this study compiled all S-curves appearing in each budget percentage range in past projects. A project manager then selected the optimal curve shape for each work item to determine the daily budget allocation and cost control limits throughout the work duration of each work item. Testing revealed that the proposed model facilitates project managers’ budget allocation decision-making, determines budget control limits for the overall project and for each work item and identifies work items that may be out of control at an early stage
Macrophage migration inhibitory factor (MIF) family in arthropods : Cloning and expression analysis of two MIF and one D-dopachrome tautomerase (DDT) homologues in Mud crabs, Scylla paramamosain
Acknowledgements This research was supported by grants from the National Natural Science Foundation of China (Nos. 31172438 and U1205123), the Natural Science Foundation of Fujian Province (No. 2012J06008 and 201311180002) and the projects-sponsored by SRF. TW received funding from the MASTS pooling initiative (The Marine Alliance for Science and Technology for Scotland) funded by the Scottish Funding Council (grant reference HR09011) and contributing institutions.Peer reviewedPostprin
Existence theorems for a crystal surface model involving the p-Laplace operator
The manufacturing of crystal films lies at the heart of modern
nanotechnology. How to accurately predict the motion of a crystal surface is of
fundamental importance. Many continuum models have been developed for this
purpose, including a number of PDE models, which are often obtained as the
continuum limit of a family of kinetic Monte Carlo models of crystal surface
relaxation that includes both the solid-on-solid and discrete Gaussian models.
In this paper we offer an analytical perspective into some of these models. To
be specific, we study the existence of a weak solution to the boundary value
problem for the equation - \Delta e^{-\mbox{div}\left(|\nabla u|^{p-2}\nabla
u\right)}+au=f, where are given numbers and is a given
function. This problem is derived from a crystal surface model proposed by
J.L.~Marzuola and J.~Weare (2013 Physical Review, E 88, 032403). The
mathematical challenge is due to the fact that the principal term in our
equation is an exponential function of a p-Laplacian. Existence of a
suitably-defined weak solution is established under the assumptions that
, and . Our investigations reveal that the
key to our existence assertion is how to control the set where
-\mbox{div}\left(|\nabla u|^{p-2}\nabla u\right) is
Political leader survival:does competence matter?
We examine whether economic and military competence of political leaders affect their duration in office. We introduce leader heterogeneity in the selectorate theory of Bueno de Mesquita et al. (2003) and derive the hypothesis that in the presence of a revolutionary threat, economic competence is negatively related to political survival, but that the effect is moderated by the size of the winning coalition. As military and economic competence are negatively correlated, the opposite holds for military competence. We present empirical estimates using proxies for military and economic competence in a parametric Weibull duration model that support our theoretical predictions
A note on entropic force and brane cosmology
Recently Verlinde proposed that gravity is an entropic force caused by
information changes when a material body moves away from the holographic
screen. In this note we apply this argument to brane cosmology, and show that
the cosmological equation can be derived from this holographic scenario.Comment: 5 pages, no figures;references adde
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