Feedback realizations in linear multivariable systems: model-following with stability and disturbance rejection

This paper deals with the problems of constructing a compensator for linear multi-variable systems that simultaneously ensures: (I) model-following with stability and (ii) disturbance rejection. Necessary and sufficient conditions for the solvability of the problems are given by using a geometric approach. The solvability conditions are explicit and the constructive procedure for finding a solution does not require any additional conditions for the plant.     

东京工业大学新图书馆 对大冈山校区进行再构筑的战略布局

图书馆作为大学中知识聚集型场所,应该被建造在校园中最为便利的地方。在东京工业大学大冈山校区图书馆改建工作中,新图书馆基地位于从学校主楼开始的轴线和正门与铁路相平行的轴线的交点处,是大冈山校区的动线节点。图书馆主要功能基本放置于地下两层的空间中,地面上则是大型广场和"绿丘"。三角形平面的"学习栋",以V字形结构漂浮于空中,成为具有透明感的从正门而来的视线的停顿点。     

Analysis of bonding state in pure and gold-implanted amorphous SiC by a combination of UHVEM and AES

Single crystalline α-SiC films and Au(target metal)/α-SiC(substrate) bilayer films were irradiated with 2-MeV electrons in an ultrahigh-voltage electron microscope (UHVEM) to form, in situ, pure amorphous SiC (a-SiC) and gold-implanted a-SiC. respectively. In the latter case, sample films were set so that the electron beam was incident on the gold layer. Differences in the bonding state between pure a-SiC and gold-implanted a-SiC were studied by Auger valence electron spectroscopy (AES). In pure a-SiC. the carbon valence state was markedly different from that of α-SiC but the silicon valence state was similar to that of α-SiC. In gold-implanted α-SiC. both the carbon and the silicon valence states were different from those of α-SiC. It is suggested that a high density of molecularized carbon clusters are formed in the amorphous matrix in gold-enriched a-SiC.     

Structure simulation in unidirectionally solidified turbine blade by dendrite envelope tracking model （ Ⅱ）： model validation and defects prediction

1 Introduction Commonly, a numerical model should be validated before application. Whether a simulation model for dendritic grain growth is reliable strongly depends on two aspects. 1) The model can effectively describe the anisotropy of grain growth. Th…     

Factors Affecting Heat-Induced Gel Formation of Bovine Serum Albumin

Factors affecting heat-induced gel formation of bovine serum albumin (BSA) were studied. In the presence of NaCl (I>0.05), well-developed transparent gels formed on both sides of the isoelectric point (Ip). Addition of CaCl₂ or MgCl₂ greatly suppressed gel formation on the alkaline side of Ip, but increased it a little on the acid side. Intermolecular s-s bonds contributed to the gel formation on the alkaline side of Ip but not on the acid side. From the results of the infrared spectra measurements intermolecular β-structure appears to contribute to gel formation on both sides of the Ip.     

Observation by TEM of spontaneous alloying in nanometre-sized atom clusters in the Au-Al system

Cluster-size dependence of alloying behaviour in nanometre-sized atom clusters has been studied by transmission electron microscopy, using clusters in the Au-Al system, which forms several intermetallic compounds in the phase diagram. In gold clusters of approximately 6–12 nm mean size, rapid dissolution of aluminium atoms took place and Au₂Al or AuAl₂ clusters were formed. When the size of gold clusters was increased to approximately 40 nm, no such rapid spontaneous alloying occurred. These observations suggest that there exists a critical size of initial gold clusters below which aluminide clusters are successfully formed by spontaneous alloying.     

Structure defect prediction of single crystal turbine blade by dendrite envelope tracking model

The structure defects such as stray grains during unidirectional solidification can severely reduce the performance of single crystal turbine blades. A dendrite envelope tracking model is developed for predicting the structure defects of unidirectional solidification turbine blade. The normal vector of dendrite envelope is estimated by the gradient of dendrite volume fraction, and the growth velocity of the dendrite envelope （dendrite tips） is calculated with considering the anisotropy of grain growth. The solute redistribution at dendrite envelope is calculated by introducing an effective solute partition coefficient. Simulation tests show that the solute-build-up due to the rejection at envelope greatly affects grain competition and consequently solidification structure. The model is applied to predict the structure defects （e.g. stray grain） of single crystal turbine blade during unidirectional solidification. The results show that the developed model is reliable and has the following abilities： reproduce the growth competition among the different-preferential-direction grains; predict the stray grain formation; simulate the structure evolution （single crystal or dendrite grains）.     

Minimal energy covariance control

In general, the covariance controller which assigns a specified state covariance X to the system is not unique, and the whole set of such controllers can be parametrized by a skew-symmetric matrix S of appropriate dimension. This paper describes how to minimize the control energy by using this freedom and reveals some properties of closed-loop system poles with respect to S.     

フライアッシュを用いたコンクリ一トの中性化に及ぼす暴露条件の影響

本報告はフライアッシュを使用したコンクリートの中性化についての測定結果を取りまとめたものである.シリーズⅠでは、暴露地、フライアッシュの種類、置換率における比較を行った.シリーズⅡでは、供試体の向き、設置場所、設置条件、調合条件における比較を行った.その結果、シリーズⅠにおいては、屋外暴露の場合、地域による中性化の差はあまり見られず、屋内と屋外の中性化速度係数の比は既往の実態調査結果より小さくなり、また、同一水結合材比では、フライアッシュの種類による中性化の差は認められなかった.シリーズⅡでは、中性化速度係数は屋外に置いて屋根なしより屋根ありのほうが大きい値を示し、また、建物の南側より北側のほうが小さい値となった.