摘要:

A full‐converter fed DC drive with only few damaged thyristors can still be operated under partial load with deteriorated performance. Through the investigation on the operating characteristics, this paper provides a guidance to the temporary use of faulty DC drives. All possible fault cases are categorized into nine representative modes. For each mode, the switching functions of the power switches are derived for calculating the output voltage waveforms of the faulty converter. By applying these waveforms to the DC machine, torque‐speed characteristics of each mode are obtained. The calculated converter output waveforms are experimentally verified on a 10‐Hp DC drive.

ISSN:0253-3839    

DOI:10.1080/02533839.1995.9677751

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

A task duplication heuristic, DSH, was proposed in [11]. The underlying concept of the task duplication heuristic is duplicating some tasks on processors such that the earliest start time of tasks on processors can be reduced, that is, tasks on processors can be executed sooner. This leads to a better scheduling length. In this paper, we propose a more general task duplication heuristic,bottom‐up top‐down duplication heuristic(BTDH), for static scheduling of directed‐acyclic graphs (DAGs) on distributed memory multiprocessors. The key difference between BTDH and DSH is the method used for duplicating tasks. BTDH allows tasks to be duplicated on processors even though the duplication of tasks will temporarily increase the earliest start time of some tasks. DSH only allows those duplications which will reduce the earliest start time of tasks. Simulation results show that, for coarse‐grain DAGs, the scheduling length of BTDH is almost the same as the scheduling length of DSH. However, for medium‐grain and fine‐grain DAGs, BTDH produces better scheduling length than DSH.

ISSN:0253-3839    

DOI:10.1080/02533839.1995.9677752

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Two linear floating CMOS resistors, which are tunable by dc control voltage, and a CMOS four‐quadrant multiplier are presented. Second order effects due to mobility reduction, channel length modulation and transistor mismatch are addressed. SPICE simulations, using 3μm‐pwell parameters and a ±5V power supply, indicate that the total harmonic distortion (THD) of the proposed resistor is lower than 0.5% for applied voltages up to 1.5V amplitude, and that the 3‐dB bandwidth of the proposed resistor circuit is about 20MHz. The experimental results of discrete circuits are given to verify the theoretical analysis.

ISSN:0253-3839    

DOI:10.1080/02533839.1995.9677753

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

This paper constructs a subliminal channel in a RSA‐like variant of the Fiat‐Shamir signature scheme to transfer any secret information. The proposed subliminal channel, unlike that in El‐Gamal signature scheme, can avoid the serious shortcoming that a subliminal receiver can undetectably forge a signer's signature. In addition, our channel also overcomes almost all shortcomings from which the subliminal channel in El‐Gamal signature scheme suffer.

ISSN:0253-3839    

DOI:10.1080/02533839.1995.9677754

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

In this paper, a high‐performance silicon piezoresistive accelerometer, fabricated by bulk micromachining with an almost linear I/O (acceleration / voltage) relationship from 0 to 90g over a 400Hz bandwidth suitable for vehicle's safety system, is described. This accelerometer is composed of two glass cover caps and a Si sensing structure. The size of the sensing structure is 3.3mm × 2.05 mm × 0.15 mm. It consisted of a “mass”, a “frame”, and 4 thin beam “bridges”. The sensitivity of the accelerometer was found to be 9.6 × 10‐8(sec2/m) and a gauge factor of 18 was deduced from this value.

ISSN:0253-3839    

DOI:10.1080/02533839.1995.9677755

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Formal specifications, which represent the essential syntactic and semantic information of various possible implementations, provide a basis for software reuse. But, to find a reusable component out of thousands of stored specifications is not an easy task. The specifications, like most programs, consist of brief descriptions and specification texts. To achieve a more accurate retrieval, we use a two‐layer strategy in this paper: First, we attach keywords to each specification where we have abstracted keywords using a new method calledsemanto‐syntactical parsingwhich takes into account both the syntactic and semantic aspects of the narrative descriptions of the specifications. Second, we further consider the signatures of the specifications where we have solved some known problems. Storage, retrieval, and maintenance of the software components are supported by the facilities of an object‐oriented database management systems. The benefits obtained from such a strategy are also described.

ISSN:0253-3839    

DOI:10.1080/02533839.1995.9677756

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

This paper presents an explicit derivation of the all‐pass Routh approximants toe‐s.It then shows that the stable all‐pass Routh approximants toe‐sare exactly the same as the all‐pass Padé approximants. As a result, the derivation provides an alternative way of proving that the all‐pass Padé approximants toe‐sare always asymptotically stable.

ISSN:0253-3839    

DOI:10.1080/02533839.1995.9677757

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

ISSN:0253-3839    

DOI:10.1080/02533839.1995.9677740

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor