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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.
感应电机无速度传感器矢量控制系统的定子电阻在线辨识   总被引:16,自引:16,他引:16  
该文针对利用磁通观测器推算转子磁通的感应电机无速度传感器矢量控制系统,提出了定子电阻在线辨识法。在利用q轴磁通推算转速的基础上,该系统利用d轴磁通误差实现定子电阻在线辨识,该方案的优点是系统简单,解决了低速运行时电压模型的定子电阻变化对系统稳定性和速度控制精度的影响问题。数字仿真和实验结果验证了定子电阻在线辨识的必要性和该方案的有效性。  相似文献   
3.
Frequency response analysis (FRA) is a powerful technique to detect internal abnormalities within power transformers. However, diagnosis criteria of power transformers by FRA have not been fully established yet. In this paper, a new evaluation method of degree of identification between two transfer functions is proposed. In the proposed method, a frequency window is employed and cross‐correlation factor is calculated with moving the window. Furthermore, the proposed method is applied to transfer functions of real transformers with or without some abnormalities. Based on this discussion, objective criteria for diagnosis of abnormalities of transformer windings by FRA are proposed. The proposed criteria are based on a few data of transformers with some abnormalities. Therefore, the proposed criteria are tentative and they would be improved by accumulation of further data.  相似文献   
4.
In the early morning of January 17, 1995, an earthquake of magnitude 7.2 occurred, with its epicenter in Awaji Island, to the south of Kobe City located near Osaka City. It was later named the Hanshin-Awaji Earthquake.

The earthquake left over 6,400 people dead and about 40,000 injured, completely destroying over 100,000 houses and buildings, causing about 300 fires, resulting in the suspension of such “lifelines” as city water, electricity, and gas supply, and halting transportation systems including road and railway traffic. It inflicted extensive damage not only on Kobe, but also on Osaka and other cities.

In the light of destruction caused by the earthquake, in 1997, the Osaka Municipal Government, the Osaka City Regional Preparedness Plan, which includes citizen evacuation in the event of earthquake, construction of seismic-resistant facilities, and fire-fighting and other emergency activities. The original plan was prepared, on the basis of an inter-plate earthquake occurring beneath the Pacific Ocean. In addition to this hypothesis, the new plan also incorporates the assumption that an earthquake with its epicenter under Osaka could occur due to movement of the Uemachi Faults running under the central part of the City in the north-south direction. Estimated damage that could be incurred through this potential earthquake were used for the latter plan.  相似文献   
5.
6.
广色域印刷     
一、广色域印刷产生的背景是什么呢: 1.时代发展的需要 当前,利用数码相机进行原稿输入的普及,喷墨打印机的广泛使用,以及随着RGB数字工作流程体系的构筑,为了适应这佯的印刷环境,使得广色域的印刷开始并将得到广泛的应用.  相似文献   
7.
Ovalbumin freeze-dried with or without the addition of glucose was stored at 50°C and 65% relative humidity to study the effect of the Maillard reaction on some physical properties of ovalbumin. In the early stage of the reaction in which ovalbumin-glucose complexes were formed, there were soluble types of monomer and aggregates of which α-helix and available lysine contents were gradually decreased with length of storage and degree of aggregation. These compounds were characterized by properties possessing a marked resistance towards destruction of conformation and coagulation. With progress of the reaction, ovalbumin-glucose complexes changed to insoluble forms having higher particle weight and breakdown products.  相似文献   
8.
An identification algorithm is considered for unknown spatially varying diffusivities in the diffusion equation by using the regularization method. The diffusion equation is expressed by a parabolic partial differential equation and the identification for the system possesses ill-posedness. To solve this problem we use the regularization method which was proposed by Kravaris (1984) and Kravaris and Seinfeld (1985). The diffusivities for air pollution problems are identified under the assumption that the diffusivities are affected by the wind velocity, Using this algorithm, the NO, concentrations caused by motor vehicles near a roadway in Tokushima, Japan are estimated.  相似文献   
9.
A complete solution is given for the inverse problem of LQ optimal regulators for the discrete-time multi-input case. The Kalman equation for discrete-time systems is derived to characterize the optimal regulators. It is then shown that this equation holds for some quadratic weighting if and only if the feedback satisfies a condition corresponding to the circle criterion for continuous-time systems. The optimality criterion given here consists of this condition and an additional condition to ensure detectability. An example is given to illustrate the results.  相似文献   
10.
It is of prime importance to maintain voltage profile within the proper range in distribution systems with a large amount of photovoltaics and electric vehicles (EVs). In particular, there is a possibility that line drop compensation (LDC) logic, which is utilized for the control of load ratio tap transformer (LRT) does not work properly when reverse power flow is included partially. Hence, in this paper, we have developed a new LRT control method based on the sensor information supposing that some section switchgears with sensors are introduced in the future distribution systems. Specifically, the extreme value of voltage profile is estimated by convergence calculation in the section between the section switchgear with sensor and LRT. Moreover, the voltage at the end node can be estimated by LDC method using sensor information of section switchgear. The proposed method was tested using a distribution system model and its effectiveness was shown.  相似文献   
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