Rebound prediction of excavated ground using anisotropic elastic finite element analysis

The finite element method is widely used in predicting the ground rebound on the excavation bottom surface. However, no case has been found where cenisotropie properties of theground were thoroughly analyzed and taken into account. In view of this, the authors conducted the elastic finite element analysis by taking into account the laminar anisotropy of the ground material, and introduced a scale of laminar anisotropy for setting up appropriate ground constants for a ground analysis in a single direction. Analyses by this method from two excavation sites with different ground properties have shown that an accurate rebound can be predicted using an elastic finite element method that considers the anisotropy of the ground.     

Stabilizing control of power system using fuzzy control

This paper presents an application of fuzzy control to enhance power system stability. The proposed control consists of the controller for large disturbance (FU 1), the fuzzy controller for small disturbance (FU 2), and the fuzzy judgment mechanism (FU 3). FU 1 is determined based on the fuzzy controller [FU 1(F)] is determined according to the control rules and its input signals, i.e., speed deviation and acceleration at every sampling time of the machine. FU 2 consists of two controllers, namely, FU 2-ω and FU 2-P; FU 2-ω has the same mechanism as FU 1, while the output signal of FU 2-P is determined according to the rules together with the change of error of electrical power and terminal voltage. To obtain the optimal desired control signal during both the large and the small disturbances, the operations of FU 1 and FU 2 are judged by FU 3, where the magnitude of speed deviation is chosen as its input signal. The determined control signal is fed to AVR of the machine. The implementation of the proposed control is simple due to the small amount of calculations and required data. The effectiveness of the proposed control is demonstrated by the one-machine infinite-bus system model and very good system performance is obtained throughout all the simulations.     

有线与无线技术结合的接入网

通信市场目前正面临着急剧的变化，利用被称作接入网的有线和无线技术的用户接入设备也相应问世，富士通过在局用交换机ＦＥＴＥＸ－１５０及光接入网传输设备中采用了国际标准规格的Ｖ５接口，以推进网络的开放和灵活适应高度复杂化的通信网，另外，为迎接终将到来的多媒体时代，富士通的ＡＴＭ／ＶＯＤ等宽带业务用接入网系统的开发也正在进行。     

Reliability and degradation behaviors of semi-insulating Fe-doped InP buried heterostructure lasers fabricated by movpe and dry etching technique

We clarified the degradation behavior of semi-insulating buried heterostructure lasers in which mesa structures were fabricated by RIE and then buried by MOVPE. The degradation rate and mode correlated with the quality of the BH interface. Based on the correlation, a condition for highly stable SIBH lasers was demonstrated and confirmed experimentally and statistically.     

Chemical cross-linking of cholesteric liquid-crystalline hydroxypropyl cellulose with dialdehydes

Cross-linking of the cholesteric liquid-crystalline order in a hydroxypropyl cellulose (HPC) aqueous solution was attempted and the swelling and mechanical (static and dynamic) properties of cast films were determined. HPC solid films cast from the liquid-crystalline aqueous solution with dialdehyde (glyoxal or glutaraldehyde) and hydrochloric acid were insoluble in water and retained the right-handed cholesteric liquid-crystalline order. The swelling and static tensile properties exhibited a general behaviour with respect to the concentration of the cross-linking agent and to the heat treatment. However, dynamic and loss moduli exhibited an opposite behaviour to the static tensile modulus. A cross-linking mechanism is proposed for HPC molecules and dialdehydes based on the swelling and mechanical properties of HPC films cast from two dialdehyde systems.     

800 MHz v.c.o. for land mobile radio synthesisers

A compact voltage-controlled oscillator, covering 1000 channels with a single range, has been designed and fabricated using GaAs varactor diodes. A c.n.r. of more than 76 dB with 25 kHz offset from carrier and an s.n.r.of more than 52 dB are obtained. Their performance characteristics are described.     

Solving fuzzy assembly-line balancing problem with genetic algorithms

Assembly-line balancing problem is known as one of difficult combinatorial optimization problems. This problem has been solved with linear programming, dynamic programming approaches, but unfortunately these approaches do not lead to efficient algorithms. Recently, genetic algorithm has been recognized as an efficient and usefull procedure for solving large and hard combinatorial optimization problems, such as scheduling problems, travelling salesman problems, transportation problems, and so on. Fuzzy sets theory is frequently used to represent uncertainty of information. In this paper, to treat the data of real-world problems we use a fuzzy number to represent the processing time and show that we can get a good performance in solving this problem using genetic algorithms.