• 한국산학기술학회논문지
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• 제9권5호
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• pp.1134-1138
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• 2008

본 논문에서는 전력분배기의 설계에 필수적인 분포정수 임피던스 변환기의 합성법을 제시하고, 이에 의하여 광대역 전력분배기를 설계한다. 변환기의 전달함수는 Chebyshev 근사로 합성하며, 변환기의 소자값은 최소 삽입손실(MIL)과 리플에 대하여 계산된다. 변환기의 요구 성능은 전달함수의 MIL과 리플을 최적화함으로써 구할 수 있다. 이의 응용 예로써 $2{\sim}8GHz$에서 동작하는 4-경로 전력분배기(four-way power divider)를 설계하였다. 실험 결과, 전력분배기는 주어진 주파수 대역에서 설계치에 근접하는 성능을 나타내어, 분포정수 회로합성에 의한 변환기의 설계는 전력분배기의 설계에 유용하게 사용될 수 있음을 입증하였다.

• 한국산학기술학회논문지
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• 제7권4호
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• pp.602-607
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• 2006

본 논문에서는 전력 증폭기 설계에 유용한 분포정수 임피던스 정합회로의 합성법을 제시하고, 이에 의하여 RF 전력 증폭기를 설계하였다. 분포정수 정합회로의 전달함수는 Chebyshev 근사에 의하여 유도되며, 주어진 구조의 회로 소자 값은 최소 삽입손실과 리플의 함수로 주어진다. 이의 응용 예로써 전력 트랜지스터를 로드 풀(load-pull) 데이터로 모델링한 다음, 정합회로 합성을 이용하여 200~900MHz의 대역에서 17dB의 이득 및 20W의 출력 전력에서 -43dBc 이하의 IM3을 갖는 전력 증폭기를 설계하였다. 제작된 증폭기는 주어진 대역에서 설계치에 근접하는 특성을 나타내어 전달함수에 의한 분포정수 정합회로의 합성이 RF 전력 증폭기의 설계에 유용하게 사용될 수 있음을 입증하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.1259-1264
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• 1990

During the past two decades, a lot of researches have been done on the synthesis of grassroot heat exchanger networks(HEN). However, few have been dedicated to retrofit of existing heat exchanger networks, which usually use more amount of utilities (i.e. steam and/or cooling water) than the minimum requirements. This excess gives motivation of trades-off between energy saving and rearranging investment. In this paper, an algorithmic-evolutionary synthesis procedure for retrofitting heat exchanger networks is proposed. It consists of two stages. First, after the amount of maximum energy recovery(MER) is computed, a grass-root network featuring minimum number of units(MNU) is synthesized. In this stage, a systematic procedure of synthesizing MNU networks is presented. It is based upon the concept of pinch, from which networks are synthesized in a logical way by the heuristics verified by the pinch technology. In the second stage, since an initial feasible network is synthesized based on the pre-analysis result of MER and must-matches, an assignment problem between new and existing units is solved to minimize total required additional areas. After the existing units are assigned, the network can be improved by switching some units. For this purpose, an improvement problem is formulated and solved to utilize the areas of existing units as much as possible. An example is used to demonstrate the effectiveness of the proposed method.

• 대한전자공학회논문지TC
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• 제46권11호
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• pp.50-55
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• 2009

본 논문에서는 분포정수 회로합성을 이용하여 최적의 정전용량 흡수 능력을 갖는 분포증폭기를 설계한다. 증폭기를 구성하는 여파기의 전달함수는 저역통과 Chebyshev 근사로 합성하며, 이의 정전용량 흡수 능력은 최소 삽입손실(MIL)과 리플의 함수로 계산한다. 분포증폭기의 능동 소자는 S-퍼래미터를 이용하여 등가회로로 모델링하며, 이의 정전용량은 전달함수의 MIL과 리플을 적절히 조정함으로써 여파기 구조로 흡수한다. 이의 응용 예로써, 0.1~7.5GHz의 주파수 대역에서 약 12.5dB의 이득을 갖는 분포증폭기를 설계하며, 실험을 통하여 정전용량 흡수 능력을 고려한 분포정수 회로합성이 분포증폭기의 설계에 유용하게 이용될 수 있음을 입증한다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1986년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 17-18 Oct. 1986
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• pp.613-618
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• 1986

In this study a s/w system(HENSPIN) for the automatic synthesis of HEN(heat exchanger network) was developed based on Pinch Design Method. The synthesized HEN by HENSPIN are satisfying performance targets such as minimum utility usage with as few as possible capital items. The invented network is near optimal in capital and operating cost. It will be used as initial structure for evolution to the structure which has optimal operability.

• 대한기계학회논문집A
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• 제20권11호
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• pp.3507-3515
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• 1996

This paper presents an attempt to find the physical structure of dynamic systems which achieves the behavior of a given system function. The scheme pursued by the paper would be regarded as synthesizing dynamic systems, and a method to synthesize them analytically is proposed by means of bond graph prototypes. The method adopts several conceptsused to synthesize networks in the electrical field, but yet deconstrates its own strengths such as the freedom from assigning causality and determining junction types. Also, itis shown that this method has further advantages in reticulating a given specification into feedforward and feedback components relative to network synthesis and the method is examined though an example to trace the outline of the analytical synthesis of dynamic systems using bond graph prototypes.

• International Journal of Computer Science & Network Security
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• 제21권3호
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• pp.304-310
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• 2021

The paper presents problems of optimization of the synthesis of embedded systems, in particular Pareto optimization. The model of such a system for its design for high-level of abstract is based on the classic approach known from the theory of task scheduling, but it is significantly extended, among others, by the characteristics of tasks and resources as well as additional criteria of optimal system in scope structure and operation. The metaheuristic algorithm operating according to this model introduces a new approach to system synthesis, in which parallelism of task scheduling and resources partition is applied. An algorithm based on a genetic approach with simulated annealing and Boltzmann tournaments, avoids local minima and generates optimized solutions. Such a synthesis is based on the implementation of task scheduling, resources identification and partition, allocation of tasks and resources and ultimately on the optimization of the designed system in accordance with the optimization criteria regarding cost of implementation, execution speed of processes and energy consumption by the system during operation. This paper presents examples and results for multi-criteria optimization, based on calculations for specifying non-dominated solutions and indicating a subset of Pareto solutions in the space of all solutions.

• 한국유전체학회:학술대회논문집
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• 한국유전체학회 2006년도 The 15th Korean Genome Organization Conference KOGO 2006 Annual Meeting
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• pp.63-63
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• 2006

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 Proceedings of the Korea Automatic Control Conference, 11th (KACC); Pohang, Korea; 24-26 Oct. 1996
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• pp.376-379
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• 1996

Synthesis for qualitative analysis in connection with quantitative analysis from the pinch design method, EVOP and Operations Research is proposed for the optimal synthesis of heat exchanger networks, that is through of the transportation model of the linear programming for synthesizing chemical processing systems, to determine the location of pinch points, the stream matches and the corresponding heat flowrate exchanged at each match. In the second place, according to the optimization, the optimal design of heat transfer enhancement is carried on a fixed optimum heat exchanger network structure, in which this design determines optimal operational parameters and the chosen type of heat exchangers as well. Finally, the method of this paper is applied to the study of the optimal synthetic design of heat exchanger network of constant-decompress distillation plants.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2002년도 춘계학술대회논문집
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• pp.273-277
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• 2002

This paper describes an optimal synthesis method of binary neural network(BNN) for an approximation problem of a circular region and synthetic image having four class using a newly proposed learning algorithm. Our object is to minimize the number of connections and neurons in hidden layer by using a Newly Expanded and Truncated Learning Algorithm(NETLA) based on the multilayer BNN. The synthesis method in the NETLA is based on the extension principle of Expanded and Truncated Learning (ETL) learning algorithm using the multilayer perceptron and is based on Expanded Sum of Product (ESP) as one of the boolean expression techniques. The number of the required neurons in hidden layer can be reduced and fasted for learning pattern recognition.. The superiority of this NETLA to other algorithms was proved by simulation.