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1.
Behavior of deuterium atoms in fused silica, which were implanted by 80-keV D+ (D2+, D3+) ions or doped thermally by D2 (or D2O), was studied by infrared Fourier transform spectroscopy (FTIR) and by ESR spectroscopy. When 80-keV deuteron ions are implanted into fused silica, OD bonds are formed. The OD bonds are also formed by thermal doping with D2 or D2O. When the deuterated silica is γ-ray irradiated at 77 K, D atoms are formed by rupture of the OD bonds. The efficiency of the OD bond rupture in the deuteron-implanted silica is much less than that in the D2-doped silica. It is concluded from the results of thermal annealing that the low efficiency of the OD bond rupture in the deuteron-implanted silica is due to the radiation damage accompanying the implantation process. However, the decay rate and detrapping energy of deuterium atoms, once formed in the silica, are similar in both cases.  相似文献   
2.
Electric vehicles (EVs) are expected to play a leading role in the changeover from fossil fuels to clean energy. However, EVs are currently not very popular, owing to their short cruising distance and long charging time. Wireless power transfer from the infrastructure to running EVs is expected to be the solution to these problems. Electric vehicle and electrified roadway (EVER) has been proposed as a wireless power transfer system for EVs while in motion. Via‐wheel power transfer (V‐WPT) is expected to be a wireless power transfer scheme for EVER. We designed and prototyped a 1:32 scale model of a V‐WPT system that consists of an RF inverter, an electrified roadway, a rectifier, and an EV with a dc motor. The output power of the prototype RF inverter was 5.9 W and the dc–RF conversion efficiency was 36.6%. The LC matching circuits for the V‐WPT were designed with two‐port conjugate matching because S11 of the V‐WPT was intrinsically –0.06 dB. After matching, the S11 value was reduced to –21.5 dB. The power transmission efficiency of the V‐WPT system was 75%. The RF–dc conversion efficiency of the rectifier was 62%. The total efficiency of the EVER system was 24.2%.  相似文献   
3.
Decision making in real problems is done in a fuzzy environment. Thus, Fuzzy-Bayes decision rules have been proposed to cope with a fuzzy state of nature. These decision rules are based on the probability of fuzzy events, or the possibility measure of fuzzy events. Furthermore, a decision rule based on fuzzy utility functions and the possibility distribution of fuzzy events are constructed. However, in these decision rules the fuzziness of the fuzzy expected utility is very big, because these decision rules are based on the extension principle for calculation of the fuzzy expected utility. In this article, avoiding the large fuzziness of the expected utility, we proposed a simple decision rule based on the representation interval of the possibility distributions of fuzzy events and the representation value of the fuzzy utility function. Further, we discuss the application of this simple decision rule to the decision problems, in which the decision maker obtains the one-peak symmetric possibility distribution of a state of nature and the one-peak symmetric membership functions of fuzzy events on a state of nature, by his or her knowledge and his or her belief.  相似文献   
4.
A multi-objective discounted Markov decision process (MDP) with expectation and variance criteria is discussed. First, difficulties in variance minimization are discussed and it is shown that variance minimization is much more difficult than the expectation optimization. Then, the multi-objective MDP with expectation and variance criteria is formulated as a multi-objective non-linear programming problem. An algorithm for finding a stationary satisfactory Pareto policy is proposed by applying the satisficing trade-off method of Nakayama. In the proposed algorithm, a decision-maker need not have a high degree of judgment and it is easy to take the balance of expectation and variance criteria and furthermore, the number of auxiliary optimization problems to be solved is quite small. Numerical examples show the efficiency of the proposed algorithm.  相似文献   
5.
朱海鹏  孔宇航   《风景园林》2021,28(12):77-84
运动视知觉是观察者认知建成环境的重要方式。全景视觉技术的发展为多视角、定量地研究园林游观体验的影响因素与作用机制提供了新思路。以生态学知觉为理论基础,借助全景影像技术重新解析园林游观体验的视知觉线索,并提出动态环境视觉信息的测度和分析方法。以苏州留园中的游园路径与景观构成为对象,定量化、可视化解析游观过程中的视觉信息的变化规律与特征,为园林游观体验机制的研究提供参考。  相似文献   
6.
7.
Moisture Sorption Characteristics of Kudzu Starch and Sweet Potato Starch   总被引:1,自引:0,他引:1  
Moisture sorption characteristics of kudzu starch and sweet potato starch were investigated based on the results of moisture sorption isotherms at 11°C, 20°C and 30°C, thermal analysis, isosteric heat of sorption and entropy of sorption. The water of crystallization in sweet potato starch was strongly retained compared with that in kudzu starch. Differences in amount of moisture sorbed between kudzu starch and sweet potato starch seemed to be attributable to the stability of the microscopic structure. The interaction of moisture-sweet potato starch was stronger than that of moisture-kudzu starch. Amount of moisture sorbed and strength of moisture-starch binding of the starches, preheated to 110°C, decreased compared with those of the starches vacuum-dried at 20°C because of release of water from the amorphous part of the starch granule.  相似文献   
8.
The effects of filtering through bleaching media on decrease of peroxide value (PV) of autoxidized soybean oil were investigated to improve its quality. Sixteen kinds of filtering and bleaching media were employed. The standard activated clay was the most effective in decreasing the peroxides in autoxidized soybean oil. The relations between the decrease of PV and the physical or the chemical properties of the media were examined. It was found that peroxides are reduced in proportion to the amount of acid at the highest acid strength range + 1.5–5.6 rather than amount of acid at the lower acid strength range, total amount of acid or specific surface area of medium.  相似文献   
9.
Tungsten was exposed to pure Ar or Ne plasmas over 1550 K at several incident ion energies. Even under the irradiation condition that the tungsten nanostructure is formed by He plasma irradiation, holes/bubbles and fiberform nanostructures were not formed on the surface by exposure to Ar or Ne plasmas. In addition, the results from energy dispersive X-ray spectroscopy supported the facts that Ar and Ne did not remain in the sample. We will discuss the reason for the diferences in the damage to the tungsten surface exposed to noble gas plasmas.  相似文献   
10.
This paper proposes a novel variable flux reluctance motor without dc‐field coils. The stator of this motor has only armature coils. The proposed motor can control the torque‐speed characteristics by increasing or decreasing the field voltage that is superimposed on the armature currents. In this paper, the operational principle of the motor is described, and the N–T characteristics are computed by finite element analysis under vector control. In addition, the N–T characteristics are compared with a conventional variable flux reluctance machine with armature and dc‐field coils.  相似文献   
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