Wichita State University

About: Wichita State University is a education organization based out in Wichita, Kansas, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 4988 authors who have published 9563 publications receiving 253824 citations. The organization is also known as: WSU & Fairmount College.

Holocene shallow-subtidal dolomitization by near-normal seawater, northern Belize

Abstract: Calcic dolomite cements compose an average of 5% of the upper 4.3 m of subtidal deposits 18 O (+2‰) compositions of the high-Sr dolomites (mean October 1900 ppm), together with near-normal salinity and inherently normal Mg/Ca ratio of pore fluids, suggest precipitation from near-normal seawater. Tidal and wind-driven circulation of seawater through the sediments supplies most of the Mg for dolomitization, which appears to be promoted by elevated pore-water alkalinity resulting from bacterially mediated oxidation of organic matter and, locally, early stages of methanogenesis. Rapid dolomitization here supports the idea that significant quantities of dolomite can form syndepositionally, from normal seawater, in shallow subtidal deposits.

Soil Respiration in Different Agricultural and Natural Ecosystems in an Arid Region

Abstract: The variation of different ecosystems on the terrestrial carbon balance is predicted to be large. We investigated a typical arid region with widespread saline/alkaline soils, and evaluated soil respiration of different agricultural and natural ecosystems. Soil respiration for five ecosystems together with soil temperature, soil moisture, soil pH, soil electric conductivity and soil organic carbon content were investigated in the field. Comparing with the natural ecosystems, the mean seasonal soil respiration rates of the agricultural ecosystems were 96%–386% higher and agricultural ecosystems exhibited lower CO2 absorption by the saline/alkaline soil. Soil temperature and moisture together explained 48%, 86%, 84%, 54% and 54% of the seasonal variations of soil respiration in the five ecosystems, respectively. There was a significant negative relationship between soil respiration and soil electrical conductivity, but a weak correlation between soil respiration and soil pH or soil organic carbon content. Our results showed that soil CO2 emissions were significantly different among different agricultural and natural ecosystems, although we caution that this was an observational, not manipulative, study. Temperature at the soil surface and electric conductivity were the main driving factors of soil respiration across the five ecosystems. Care should be taken when converting native vegetation into cropland from the point of view of greenhouse gas emissions.

Solving geometric constraint systems. I. A global propagation approach

Abstract: We describe a geometric constraint solving method/system that takes the declarative description of geometric diagrams or engineering drawings as input and outputs a sequence of steps to construct the diagram with ruler and compass if it succeeds. We extend the local propagation to a global one. Like the local propagation, the global propagation tries to determine the position of a geometric object from the set of geometric objects whose positions are already known. However, our global propagation uses not only the constraints involving this object but also implicit information derived from other constraints. The algorithm can be used to build intelligent CAD and interactive computer graphic systems.

Analytical Estimation of Path Duration in Mobile Ad Hoc Networks

Abstract: Path duration is an important design parameter that determines the performance of a mobile ad hoc network (MANET). For example, it can be used to estimate the route expiry time parameter for routes in “on demand” routing protocols. This paper proposes an analytical model to estimate path duration in a MANET using the random way point mobility model as a reference. The salient feature of the proposed model is that it establishes a relationship between path duration and MANET design parameters including node density, transmission range, number of hops, and velocity of nodes. Although this relationship has been previously demonstrated through simulations, a detailed analytical model is not available in the literature to present. In particular, the relationship between path duration and node density has not been derived in previous models. The accuracy of the proposed model is validated by comparing the results obtained from the analytical model with the experimental results available in literature and with the results of simulations carried out in ns-2.