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101.
In this research, we propose and evaluate a decision support system using an interactive large-scale high-resolution display. This decision support system supports the summarization and decision-making of a large amount of disaster information during the occurrence of a large-scale natural disaster. Municipal employees at the disaster control headquarters can display disaster information on the large-scale display with a touch or flick on a laptop or tablet. To evaluate the operability, readability, functionality, and necessity of the decision support system, we surveyed 23 municipal employees in the disaster prevention division using a questionnaire. The system received a great evaluation in all the evaluation items.  相似文献   
102.
Applying the Voronoi diagram to the cell system for the finite volume method, a new method on the unstructured grid system is devised for the simulation of incompressible steady flow. In this method, the SIMPLE algorithm can be applied with little expansion. The turbulent flow around the two-dimensional vehicle model is simulated with the k-ε turbulence model by this method. Comparing the calculation result with another result obtained using the structured grid system and the experimental data, the new method is shown to be suitable for the simulation of complex flow fields.  相似文献   
103.
An Examination of Qubit Neural Network in Controlling an Inverted Pendulum   总被引:1,自引:0,他引:1  
The Qubit neuron model is a new non-standard computing scheme that has been found by simulations to have efficient processing abilities. In this paper we investigate the usefulness of the model for a non linear kinetic control application of an inverted pendulum on a cart. Simulations show that a neural network based on Qubit neurons would swing up and stabilize the pendulum, yet it also requires a shorter range over which the cart moves as compared to a conventional neural network model.  相似文献   
104.
105.
In order to make a breakthrough for the acute problem of water shortage in the world, the key words "decentralization and re-use" are very important for new sustainable sanitation systems that will be developed. Therefore, we focused on a new treatments system called "a slanted soil treatment system" which combines a biotoilet system with a domestic grey water treatment system. Because this system is a low cost and compact system, the system can be easily introduced to homes in urban areas or in the suburbs of cities in many developing countries. In this study, we performed on site experiments carried out on Shikoku Island, Japan, for several years. We obtained the following results. The slanted soil treatment system could remove organic pollutants and total nitrogen and total phosphorus in grey water effectively. Furthermore, the system performance became high in the case of the high concentration of the influent water. The nitrification reaction and denitrification reaction were speculated to exist due to aerobic zones and anaerobic zones present in the slanted soil treatment system. The slanted soil treatment system could perform for approximately 3 years with zero maintenance. The plug flow model of 1st order reaction kinetics could describe the reaction in the slanted soil treatment system. However, it is necessary to improve the system to maintain the performance in all seasons.  相似文献   
106.
This study analysed the technical and publication activities of the Institute of Electrical and Electronics Engineering (IEEE), the most influential academic publisher in engineering. We first constructed an original comprehensive database of periodicals (journal and magazine) and conference proceedings published by the IEEE between 1980 and 2008, which comprised approximately 0.36 million periodical articles and 1.14 million conference articles. We analysed the transitions in technical innovations from two perspectives: trends within (1) individual countries and (2) specialized fields represented in IEEE societies. The number of published periodical articles increased fourfold between 1980 and 2008, while that of published conference articles increased nearly 20-fold in the same period. In particular, the number of conference articles published by China increased dramatically from 2002, exceeding even the number published by the US in 2008. The IEEE has increasingly shifted away from its US-centred origins to literally becoming the ‘electrical and electronics association of the world’. The proportion of articles published by authors in North America, Europe and East Asia has increasingly balanced, thus leading to the formation of a tri-polar structure of IEEE technological activities. This comprehensive analysis of IEEE publications over a period of almost 30 years revealed that with the emergence of more active international competition, ‘glocalisation’ is occurring among publications and research activities of the IEEE. Consequently, quantitative analysis revealed structural changes in global competition and technological transition characterized by five phases.  相似文献   
107.
The thermocapillary convection instability in shallow annular pools with Prandtl numbers (Pr) from 0.011 to 57.9, differentially heated at the outer wall and cooled at the inner wall, is investigated numerically. The critical Marangoni numbers (Ma c ), critical azimuthal wave numbers (m c ) and critical phase velocities (ω c ) for the incipience of oscillatory flow are determined by linear stability analysis. The results indicate that the Ma c increases steeply with increase of Pr number when Pr≤15.9, while it increases slightly with increase of Pr between Pr=23.9 and 57.9. The m c and ω c decrease with increase of Pr number.  相似文献   
108.
The effects of irradiation of a Nd-Fe-B permanent magnet by fast neutrons was investigated. The decrease in measured magnetic flux density at the center of the magnets were 0.6%, 6.9%, 25.2% and 47.3% after continuous irradiation of 1.1 kGy, 3.7 kGy, 5.6 kGy and 7.4 kGy, respectively. On the other hand, the decrease due to non-continuous irradiation, in which the magnet was first irradiated at 3.7 kGy, then irradiated again at 3.7 kGy nine months later, was 14% smaller than that of continuous irradiation, even for the same total dose. The temperature coefficient of the magnetization did not change with irradiation. Some radioactive materials, such as 147Nd, 151Pm, and 54Mn, were detected in the magnet after irradiation.  相似文献   
109.
Waste is generated at the moment when the operation of a fusion reactor is halted and maintenance is started for periodic replacement of blanket modules and divertor. Used blanket and divertor need to be replaced shortly after the shutdown for high plant availability, as long as high surface dose rate and decay heat of the blanket and divertor can be handled. In this sense, nuclear characteristics of the blanket and divertor need to be understood for a reasonable maintenance scheme. For the purpose, neutronic calculations were carried out on the blanket and divertor using a THIDA-2 code with FENDL-2.0. For a SlimCS DEMO reactor, the calculated decay heat for each 1/12-sector was as high as 5 MW just after the shutdown and 0.3 MW one month later. For the maintenance, a cooled shielding structure (CSS) was proposed to remove the decay heat and to shield gamma-rays from the sector. When maintenance is done one month after the shutdown, the sector temperature is maintained to be 550 °C or lower with the cooling by the CSS of 50 °C. In order to avoid tritium release from the sector during the maintenance, a cask should be used to transport the sector. For efficient use of resources, breeding and neutron multiplying materials should be reused or recycled. A possible strategy for reuse or recycle is also presented.  相似文献   
110.
The kinetics of methane reforming over Ru/γ-Al2O3-catalyzed high porosity Ni-Cr-Al foam were examined at temperatures of 650-900 °C in a quartz tubular reactor using an electric furnace. The kinetic data were analyzed by four different types of kinetic models based on the basic, Eley-Rideal, Langmuir-Hinshelwood, and stepwise mechanisms. Validation of the kinetic models was carried out by calculating the determination coefficient r2 between the predicted and the experimental results for each model. The absolute average deviation percentage (AAD%) between the predicted and the experimental results was also estimated for each model. The kinetic model based on the reversible stepwise mechanism provided the best prediction of the experimental reforming rates with an AAD value of 6% in the range 650-850 °C.  相似文献   
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