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Container stacking rules are an important factor in container terminal efficiency. In this paper, we investigate two concepts to increase efficiency and compare them to several benchmark algorithms, using a discrete-event simulation tool. The first concept is to use knowledge about container departure times, in order to limit the number of reshuffles. We stack containers leaving shortly before each other on top of each other. The second concept is the trade-off between stacking further away in the terminal versus stacking close to the exit points and accepting more reshuffles. It is concluded that even the use of imperfect or imprecise departure time information leads to significant improvements in efficiency. Minimizing the difference in departure times proved to be important. It was also found that the trade-off between stacking further away in the terminal versus stacking close by the exit points and accepting more reshuffles leads to improvements over the benchmark.  相似文献   
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Integrins play a central role in cellular adhesion and anchorage of the cytoskeleton and participate in the generation of intracellular signals, including tyrosine phosphorylation. We have recently isolated a cDNA encoding a unique, focal adhesion-associated protein tyrosine kinase (FAK) that is a component of an integrin-mediated signal transduction pathway. Here we report the isolation of cDNAs encoding the C-terminal, noncatalytic domain of the FAK kinase, termed FRNK (FAK-related nonkinase). Both the FAK- and FRNK-encoded polypeptides, pp125FAK and p41/p43FRNK, are expressed in normal chicken embryo cells. pp125FAK and p41/p43FRNK were localized to focal adhesions, suggesting that pp125FAK is directed to the focal adhesions by sequences within its C-terminal domain. We also show that the fibronectin-dependent increase in tyrosine phosphorylation of pp125FAK is accompanied by a concomitant posttranslational modification of p41FRNK.  相似文献   
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Distributed sensing systems for studying scientific phenomena are critical applications of information technologies. By embedding computational intelligence in the environment of study, sensing systems allow researchers to study phenomena at spatial and temporal scales that were previously impossible to achieve. We present an ethnographic study of field research practices among researchers in the Center for Embedded Networked Sensing (CENS), a National Science Foundation Science & Technology Center devoted to developing wireless sensing systems for scientific and social applications. Using the concepts of boundary objects and trading zones, we trace the processes of collaborative research around sensor technology development and adoption within CENS. Over the 10-year lifespan of CENS, sensor technologies, sensor data, field research methods, and statistical expertise each emerged as boundary objects that were understood differently by the science and technology partners. We illustrate how sensing technologies were incompatible with field-based environmental research until researchers “unearthed” their infrastructures, explicitly reintroducing human skill and expertise into the data collection process and developing new collaborative languages that emphasized building dynamic sensing systems that addressed human needs. In collaborating around a dynamic sensing model, the sensing systems became embedded not in the environment of study, but in the practices of the scientists.  相似文献   
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The influence of short-term heating or cooling and exposure to visible light on the bleaching of a gamma-irradiated glass stored at 20°C is investigated by photometry. The decay of radiation-induced color centers is retarded under the action of heating and gradually regains its initial rate after the heating ceases. The transient stage can be described as relaxation. It is revealed that isothermal photobleaching does not exhibit a similar aftereffect.  相似文献   
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Several programs based on the Fast Fourier Transform (FFT) Algorithm developed by Cooley and Tukey are available. The Cooley and Tukey algorithm for the FFT requires the number of data N be a power of 2. Along with a subroutine which implements the Cooley and Tukey algorithm, six other new subroutines which are extensions of the Cooley and Tukey algorithm are given in this paper. Some applications to geoscience, along with some examples where the FFT subroutine based on the Cooley and Tukey algorithm is undesirable also are given.  相似文献   
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Dietary alteration or intervention is an ideal method of preventing or treating hypertension. Medication may be eliminated or reduced in many cases. Correction of obesity and alcohol abuse are confirmed methods of treating hypertension. Reduction of sodium intake is effective in that portion of the population which is salt-sensitive. Probably, the ratio of sodium to potassium is of importance and increasing potassium intake while reducing sodium intake is effective in many situations. Evidence is being reported which indicates that adequate intake of calcium, and perhaps magnesium, is effective in preventing hypertension. Limited information indicates that a sufficiency of dietary essential fatty acids and fibre are effective in hypertension prevention. The role of dietary protein, carbohydrates, fat, cholesterol, vitamins, and essential elements (other than those mentioned above) in the pathogenesis has not been fully elucidated at this time, but there are indications that adequate intakes are beneficial in hypertension. Water hardness may have some effect in reducing hypertension incidence, and any effectiveness would probably result from calcium and magnesium in the drinking water. Animal studies and limited human studies indicate some detrimental effects of heavy metals, such as lead and cadmium, upon the pathogenesis of hypertension. Information regarding caffeine intake is inconclusive.  相似文献   
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