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101.
With the urgency of global warming, green supply chain management, logistics in particular, has drawn the attention of researchers. Although there are closed-loop green logistics models in the literature, most of them do not consider the uncertain environment in general terms. In this study, a generalized model is proposed where the uncertainty is expressed by fuzzy numbers. An interval programming model is proposed by the defined means and mean square imprecision index obtained from the integrated information of all the level cuts of fuzzy numbers. The resolution for interval programming is based on the decision maker (DM)’s preference. The resulting solution provides useful information on the expected solutions under a confidence level containing a degree of risk. The results suggest that the more optimistic the DM is, the better is the resulting solution. However, a higher risk of violation of the resource constraints is also present. By defining this probable risk, a solution procedure was developed with numerical illustrations. This provides a DM trade-off mechanism between logistic cost and the risk.  相似文献   
102.
Diaphragmatic eventration is the upward displacement of the abdominal viscera secondary to a thin or paralytic diaphragm. Its clinical presentations and radiographic pictures are similar to those of diaphragmatic hernia. Prenatal diagnosis of diaphragmatic eventration is extremely rare. A pregnant woman was referred to us because of abnormal cardiac findings noted at 20 weeks of gestation. A diagnosis of partial anomalous pulmonary venous connection was made on the basis of our findings of right atrial enlargement with an abnormal vascular channel drainage to it. The infant was born via cesarean section at 40 weeks and developed complications of cyanosis immediately after birth. Postnatal imaging studies and surgical findings disclosed right side diaphragmatic eventration with liver and associated vasculature upward displacement into the right pleural cavity. The cardiac structure was otherwise normal. We conclude that when an abnormal vessel tracing and unexplainable cardiac chamber asymmetry is encountered, diaphragmatic eventration should be considered as one of the differential diagnoses. Correct recognition and transferral to the hospital for neonatal assistance may lead to timely and appropriate management of these fetuses. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
103.
ABSTRACT: A distributed watershed model combining kinematic wave routing, 1‐D dynamic channel‐flow routing, and 2‐D diffusive overland‐flow routing has been developed to simulate flooding and inundation levels of large watersheds. The study watershed was linked to a GIS database and was divided into an upstream mountainous area and a downstream alluvial plain. A kinematic wave routing was adopted at the mountainous area to compute the discharge flowing into the alluvial plain. A 1‐D dynamic channel routing solving the St. Venant equations by the Preissmann method was performed for the main channel of the alluvial plain, whereas a 2‐D overland‐flow routing solving the diffusion wave equation with the Alternating Direction Explicit scheme was used for floodplains. The above two routings were connected by weir‐link discharge formula. The parameters in the model were calibrated and independently verified by single‐event storms. An example application of flooding/inundation analysis was conducted for the Taichung station and the Woozi depot (Taiwan High Speed Rail). Suggested inundation‐proofing measures ‐ including raising ground surface elevation of the station and depot and building a waterproofing exterior wall and their combination ‐ were investigated. It was concluded that building the waterproofing exterior wall had a strong tendency to decrease peak inundation depth.  相似文献   
104.
Experimental results obtained to date indicate electrokinetic extraction is viable in removing organic and inorganic contaminants from fine-grained soils. However, electrochemical reactions and soil-contaminant interactions that occur simultaneously may enhance or reduce the removal efficiency of the hazardous waste site remediation process. Many sites worldwide are contaminated by lead and its compounds, resulting in lead poisoning. It is difficult to remove lead from fine-grained soil because of the existence of a great variety of lead complexes and their pH-dependent and reversible physicochemical properties. The feasibility of electrokinetic extraction of lead from kaolinites is investigated theoretically, numerically, and experimentally in this study. This is the first paper of two companion papers presenting the theoretical and numerical modeling of the transport of lead species, and electrochemical reactions and soil-contaminant interactions occurring during the electrokinetic extraction process. The comparison between simulation results and experimental results is presented in the second paper.  相似文献   
105.
Internal solitary waves (ISWs) have been detected in many parts of the world oceans, particularly over slope-shelf topography, on which signature of waveform inversion has been identified. The effects of these waves on engineering operations and ecological process have also been reported in the literature. This article reports the results of a series of numerical modeling and laboratory experiments on waveform evolution of a depression ISW in a nearly stratified two-layer fluid system, in which specific water depth ratios above the horizontal plateau of the trapezoidal obstacle were arranged to facilitate the occurrence of waveform inversion. Classifications of waveform instability (no instability, shear instability and overturning with breaking) on the slope are confirmed in the present laboratory study. Numerical results for waveform variation are also found in fair agreement with the laboratory measurements for cases without waveform inversion and minor internal breaking. Moreover, laboratory results revealed that the depth ratio of the stratified two-layer fluid above the plateau and the magnitude of the incident ISW were the two most important factors for promoting waveform inversion beyond a turning point, in addition to the requirement of a sufficient distance from the shoulder of the trapezoidal obstacle. These factors also influenced the outcome of the shoaling process, energy dissipation, internal wave breaking and turbulent mixing on the front slope, as well as the likelihood of waveform inversion on the horizontal plateau. Contrary to the common perception, it was also observed, at least from the results of the present laboratory experiments, that not all the incident ISWs of depression would produce waveform inversion on the plateau, where the upper layer was physical greater than the bottom layer, unless moderate incident wave was provided. The outcome might also be attributed to the limited distance from the shoulder onto the plateau in the present laboratory setup. However, once waveform inversion occurred on the plateau, it was found, among others, that: (1) the amplitude of the transmitted leading crest and trough might be as low as 30 and 20%, respectively, to the amplitude of the incident wave in depression; (2) the characteristic wavelength of the transmitted leading trough doubled while that of the crest was asymptotically one-half of the incident wavelength, despite the wide range variation in the depth ratios above the plateau; and (3) the transmitted potential wave energy of the leading crest contained 30% of the incident energy. Based on the results of present laboratory experiments, the range for the non-dimensional parameter α, which indicates the effect of nonlinearity and the promotion of waveform inversion on horizontal plateau, will be proposed.  相似文献   
106.
Environmental Science and Pollution Research - This study investigated the impact of environmental engineering on existing venues, venues and operations management. First, the literature analysis...  相似文献   
107.
Tetraclita japonica and T. formosana are common intertidal barnacles with similar morphology, which leads to uncertainty in their species status. In the present study, we try to elucidate the taxonomic status of the two taxa using morphology and mitochondrial control region and cytochrome c oxidase subunit I (COI) sequences of the barnacles in their distribution range. The two taxa were found to be morphologically similar; a diagnostic difference between them was only observed in the colour of the parietes and opercular plates. Little genetic differentiation was detected in the control region and COI (ΦCT < 0.025 for both markers) between two taxa, but differentiation was found between the southern (Taiwan and Hong Kong) and northern (Japan) populations of T. japonica/T. formosana, which might be the result of isolation by distance and upwelling in summer. Our data suggest that the two presently recognized species probably represent two colour morphotypes of the same species exhibiting different geographical distribution. T. japonica is abundant in Japan and southeast coast of China, whereas T. formosana is only abundant in Taiwan. The heterogeneous environment might exert a divergent selection pressure leading to asymmetric distribution of the two colour morphotypes. The different colours might be a result of either phenotypic plasticity adaptive to environmental variables or genetic hitchhiking of local adaptive genotypes. Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.  相似文献   
108.
109.
A mathematical model which may be used for predicting the flash point of binary solutions has been proposed and subsequently verified by experimentally-derived data, such data pertaining to an almost-ideal solution as also to highly non-ideal solutions. The results reveal that the model is able to precisely predict the flash point over the entire composition range of binary solutions for both ideal solutions and non-ideal solutions by way of utilizing the flash point of the individual components. The highly non-ideal solution like octane+ethanol exhibits the minimum flash-point behavior, which leads to the minimum on the flash point vs composition curve.  相似文献   
110.
Abstract

This study was to assess the metal contamination in oyster tissue grown in the Ann-ping mariculture ground in Taiwan. the information generated from this work also revealed general metal pollution problem for Taiwan's oyster farmers. Oysters, Crassostrea gigas, and surficial sediments collected from ten locations in Ann-ping mariculture ground in Taiwan for metals concentration (Cu, Zn, Pd, Cd, Fe and Mn) were performed. Analytical results indicated that the yearly averaged oyster copper concentrations (μg g?1, wet weight) in oyster soft parts from Ann-ping increased from 21.3±4.1 in 1993; 24.1±6.8 in 1994; 36.8±11.9 in 1995 to 43.9±23.1 μg g?1, wet weight, in the 1996 raising season. the mean oyster copper concentration reached a level of 50 μg g?1, wet weight, in December 1996. This increasing trend of metal concentration in oyster tissue indicates a potential pollution source which may pose a potential disaster as green oyster incidence, which occurred on the Charting coast in 1986, in Taiwan. Sediment samples in Ann-ping mariculture ground were also collected and examined. the seasonal variation of the copper concentration in surficial sediment from Ann-ping did not show an increasing trend as observed in oyster tissue.  相似文献   
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