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41.
A virtual manipulation system for origami (paper folding) is described. A piece of paper defined in a computer can be deformed interactively by picking and moving a corner vertex of a paper face on a graphic screen using a mouse. Three kinds of folding operations and a curving operation transform the paper into a three-dimensional figure made of flat or curved surfaces. The roundness of the curved surfaces is calculated in real-time by minimizing an elastic energy function. The simulated paper has traditional Japanese decoration applied as a texture to give a more realistic appearance. It is rendered with shading in real-time.  相似文献   
42.
A novel method was proposed to judge degradation/health of lithium‐ion batteries (LIBs) using the capacitance that was estimated from the real‐time voltage and current characteristics of the batteries. It is thought that the capacitance of LIBs decreases with degradation because of undesirable components formed on the electrodes that are the main cause of the degradation. As the LIBs are active, the capacitance was evaluated from the differential equation, ?Q /?v = I /(?v /?t ) = i /(dv /dt ), using the voltage and current characteristics during the charging or discharging. The capacitances of the commercial LIBs with different SOHs; 100%, 92%, and 88% were estimated during the charging and discharging using the equation. The average capacitance in the specific voltage region of the batteries was directly proportional to the state of health. Therefore, the proposed measurement is thought to be a useful method for judging degradation of LIBs.  相似文献   
43.
Chubu Electric Power Co., Ltd.’s hybrid power system simulator consists of analog models and hybrid models. The power system facilities are downsized as an analog model, while the synchronous generators and the loads are modeled as an actual current source model through the amplifier and the digital model. In recent years, there is a growing interest in analyzing power system dynamic phenomena caused by a high penetration of distributed generations. Therefore, the multifunctional generator model that can simulate distributed generation has been developed.  相似文献   
44.
Against the backdrop of increased needs for longer operating life of turbine oils, there is a tendency to use amine-type antioxidants for steam turbine oils as well as gas turbine oils. Amine-type antioxidants are known to form sludge during the oxidation process, and the sludge formation from turbine oils involves the high risk for a power plant of bearing temperature rise caused by sludge deposition onto the bearing surface. But currently, there is no global specification to evaluate the sludge formation from turbine oils that have high rotating bomb oxidation test (RBOT) life. In this study, we examined 18 kinds of commercially produced turbine oils and two kinds of originally prepared oils with amine additives on sludge formation under 120°C dry turbine oil oxidation stability test (TOST) accelerated degradation test. Consequently, we found a criterion to check the quality of sludge resistance of turbine oils based on the relationship between the RBOT residual ratio and weight of filter residues(1μ m pore filter).  相似文献   
45.
Studies on the Characterization of Ovomucin and Chalaza of the Hen's Egg   总被引:1,自引:0,他引:1  
A study was made on the electrophoretic analysis, fractionation and characterization of chalaza, and ovomucin from thick and thin albumen of the hen's egg. The chalaza and ovomucins were confirmed to be composed of three components which the molecular weights were estimated to be 150,000, 220,000 and 400,000 daltons, and named α1, α2 and β, respectively. They were fractionated into carbohydrate poor (α1 and α2 mixture) and rich (β) components by gel filtration in the presence of SDS and 2-mercaptoethanol. In the amino acid and carbohydrate compositions, differences were observed only in the carbohydrate compositions of β-components. Sonication facilitated solubilization of the ovomucin, but some signs of degradation of subunit components were observed.  相似文献   
46.
We consider flexible manufacturing systems (FMSs) which are composed of a set of workstations linked together with a material handling system (MHS). Each workstation consists of an input buffer, a single machine and an output buffer. The MHS consisting of a single cart routes work among the workstations according to the process paths required by the work. We deal with an optimal control problem in this FMS. We model the FMS as a closed queueing network. In the model, the cart routes the work to the workstations in accordance with a Markov routing with exponentially distributed routing time, and the machines process work with exponentially distributed processing time. An objective is to find a work routing policy that maximizes the total expected reward earned by operating machines. This optimal control problem is formulated as an undiscounted semi-Markov decision process. Structural properties of an optimal policy are analysed. Moreover, a sufficient condition is derived for the optimal policy to be of control limit type. An example is given to illustrate the result.  相似文献   
47.
Three major organic matrix components, nacrein, MSI60 and N16 have been reported from the nacreous layer of Japanese pearl oyster, Pinctada fucata. Though several in vitro experiments have been carried out to elucidate the functions of these molecules details have not yet been clarified. In this report, we tempt to clarify the gene expression levels encoding the above three proteins between samples of 1) summer and winter seasons and 2) ocean and aquarium environments by using real-time polymerase chain reaction (PCR).It was confirmed that the biomineralization process of P. fucata is mainly influenced by the circatidal rhythm of the ocean environment. The gene expressions coding for N16 and MSI60 increased at the time of high tide, while that of nacrein increased at the time of low tide. The similar tendency observed in N16 and MSI60 showed the possibility that both components are secreted simultaneously, supporting a hypothesis that N16 forms cross-linkage with MSI60 to form the membrane. The expressions of MSI60, N16 and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes were remarkable in winter season, while no variation was found in the expression level of the nacrein gene in summer and winter season.The study is the first attempt regarding the seasonal and circadian rhythms observed on gene expressions incorporated into molluscan shell formation. The results will give a new insight into the relationship between molluscan physiology and the mechanism of shell formation.  相似文献   
48.
在垂直环形窄缝流道中的沸腾传热特性研究   总被引:5,自引:0,他引:5  
为了弄清在窄缝环形流道中气泡的形成、聚合和变形的特性 ,以及气泡在聚合变形之后对传热特性的影响 ,在常压下用蒸馏水对窄缝间隙为 0 75mm的垂直环形流道 ,进行了可视化的流动沸腾传热实验研究 ;实验段的有效加热长度为 90 0mm ,其加热方式为单面内侧加热 ,实验的流量变化范围为 1 667× 1 0 - 5m3/s至 5 833× 1 0 - 5m3/s。实验得到了在不同质量流密度和热流密度下窄缝流道中的沸腾传热系数随干度变化的分布。通过与常规流道中的沸腾传热系数的比较 ,得到了在窄缝环形流道中沸腾传热系数比常规流道中的沸腾传热系数约高 1 5 %的结论。另外通过用高速摄像机对可视化的垂直环形流道中的流型进行的拍摄研究 ,分清了存在在窄缝环形流道中的四种流型  相似文献   
49.
The quantitative estimation of failure stress of a lithium niobate (LN) single crystal due to thermal shock was investigated. Cylindrical test specimens were used in the thermal shock tests. The thermal stress of an LN test specimen under conditions of thermal shock cracking was calculated from a computer program which takes account of the crystal anisotropy, using the surface temperature measured in the thermal shock test. Four-point bending tests were also carried out to examine the relationship between the thermal shock cracking and the failure of a small test specimen due to mechanical load. LN single crystals fractured at the cleavage planes {0 1 1 2} in the thermal shock test and the four-point bending test. Although the failure stress data obtained from both tests obey the Weibull distribution, the Weibull distribution depends not only on specimen size but also on loading type. According to the Weibull distribution of thermal shock test data, if the normal stress σn acting on the cleavage planes {0 1 1 2} is lower than 10 MPa, the probability of thermal shock cracking becomes very small — less than 2%. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
50.
氯化消毒条件及污水水质对生成THMs、HAAs的影响   总被引:6,自引:0,他引:6  
系统地研究了消毒务件和水质在城市污水氯化消毒过程中对生成三卤甲烷和卤乙酸的影响。结果表明,投氯量对三卤甲烷和卤乙酸生成量的影响最大,投氯量为40mg/L时的生成量分别约是投氯量为5mg/L时的30倍和70倍。三卤甲烷浓度随反应时间和温度无明显变化,而卤乙酸浓度在反应2h后达到峰值并在之后逐渐降低,且随温度的升高呈下降趋势。pH对两类副产物生成的影响几乎相反,近中性条件下的三卤甲烷生成量最多而卤乙酸生成量最少。水中氨氮浓度的增加会导致三卤甲烷生成量略有下降,而卤乙酸浓度却大幅上升。溴离子浓度升高将导致三卤甲烷和卤乙酸生成量显著增加,其中三氯甲烷浓度下降,三溴甲烷浓度显著上升,混合取代的三卤甲烷浓度先增加后减少。与此类似,二氯乙酸和三氯乙酸浓度随溴离子浓度的增加而减少,含溴卤乙酸浓度则有不同程度的增加。反应温度、反应时间、pH和氨氮对污水消毒副产物生成的影响与已报道的饮用水消毒中的作用规律存在显著差异,甚至截然相反,这为有针对性地选取消毒工艺参数提供了依据。  相似文献   
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