Comparison of 80-keV D+ Ion Implantation with Thermal D2 Doping in Silica by FTIR and ESR Spectroscopy

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.     

基于数据可视化技术的逆变器用T型滤波器优化设计方法

以提高滤波器对非线性负载的适应性和整机功率密度为目的,提出一种用四维可视化技术优化非对称T型滤波器的设计方法。优化目标为降低输出阻抗和提高系统功率因数,取值范围由四维表现图的交域构成;截止角频率等约束条件的选择充分考虑到器件的电流负担和电压应力;整个设计过程在四维表现图、两参数变化的根轨迹和Bode图的可视化条件下进行,便于把握多目标函数的变化趋势,进而综合考虑各方面的因素来确定最优解。实验结果和相关数据表明所设计的低通滤波器达到了带约束条件的多目标优化目的,且该方法也可用于类似的工程优化设计。     

沈阳奥林匹克体育中心体育场创意设计

沈阳奥林匹克中心体育场设计以"月桂树之冠"为寓意主题,充分体现"绿色、科技、人文"奥运的宗旨,意在创造一座与环境共生的生态型体育场。     

OSAKA CITY'S EARTHQUAKE PREPAREDNESS IMPROVEMENT MEASURES

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.     

一种用于PWM逆变器的非对称T型滤波器的设计方法

针对以体积最小为目的的PWM逆变器用非对称T型滤波器的参数设计中会出现高次多元方程，难以获得有用的解析解的实际问题，提出了一种采用三维数据可视化技术的设计方法：在保证低通滤波器衰减特性的前提下，分别绘出纯电阻负载和阻感负载时系统功率因数的曲面，再依次考量电力电子器件中的电流负担、电压应力等因素，从空间曲面到空间曲线，再到平面曲线，逐步地缩小取值范围。最后对电感器的结构进行了优化设计。实验验证了该方法的正确性和实用价值。     

Effect of Maillard Reaction on Some Physical Properties of Ovalbumin

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.     

Distributed parameter identification by regularization and its application to prediction of air pollution

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.     

Solution to the inverse regulator problem for discrete-time systems

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.