• 소음진동
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• 제7권5호
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• pp.737-746
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• 1997

The substructure synthesis method is used for making it easy to analyze vibration systems generally in vibration field. In the past, this method has been to be used mainly because of shortage of computer memory and CPU time. But recently this method is used for analyzing complex structure or identifying the characteristics of systems precisely. The purpose of this study is to develop acoustic substructure synthesis method that can be applied to acoustic modal analysis of complex acoustic systems. Acoustic modal analysis method to be introduced here is a method that analyze acoustic natural mode shape of the complex acoustic system by the principle of CMS(component mode synthesis method). This paper describes the acoustic modal analysis of the acoustic finite element model of simple expansion pipe by acoustic substructure synthesis method. The resutls of acoustic modal analysis analyzed by Acoustic substructure synthesis method and the results by FEM(finite element method) shows good agreement.

• 음성과학
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• 제1권
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• pp.295-314
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• 1997

In this study, we will implement a flexible formant analysis and synthesis system. In the analysis part, the two-channel (i.e., speech & EGG signals) approach is investigated for accurate estimation of formant information. The EGG signal is used for extracting exact pitch information that is needed for the pitch synchronous LPC analysis and closed phase LPC analysis. In the synthesis part, Klatt formant synthesizer is modified so that the user can change synthesis parameters arbitarily. Experimental results demonstrate the superiority of the two-channel analysis method over the one-channel(speech signal only) method in analysis as well as in synthesis. The implemented system is expected to be very helpful for studing the effects of synthesis parameters on the quality of synthetic speech and for the development of Korean text-to-speech(TTS) system with the formant synthesis method.

• 한국수학교육학회지시리즈C:초등수학교육
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• 제14권1호
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• pp.27-41
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• 2011

본 연구는 분석과 종합에 대한 역사적 출발이라고 볼 수 있는 유클리드의 저작인 '자료론'과 '분할론'에 대한 분석 연구이다. Euclid의 원론에 비해 거의 관심이 없는 두 문헌에 대한 분석을 통해 사고활동으로서의 분석 및 종합에 대한 의미를 살펴보았다. 먼저 분석, 종합이 포함된 다양한 용어들에 대한 개념을 살펴보고, 이를 바탕으로 본 연구에서 사용한 분석과 종합의 개념을 명확화하였다. 또한 두 문헌에 제시된 명제에 대한 분석을 통해 분석은 '외재적 분석'과 '내재적 분석'으로 분류하였는데, 외재적 분석은 제시된 명제에 자체에서 외형적으로 드러난 수학적 대상, 요소, 성질, 속성에 대한 분석이고, 내재적 분석은 외재적 분석의 결과로 추출된 수학적 대상, 요소, 성질, 속성에 대한 재분석 혹은 결합 및 관련성의 추출을 통한 분석이다. 종합은 '이론적 종합'과 '경험적 종합'으로 분류하였는데, 이론적 종합은 경험보다는 논리적, 이성적 과정을 통한 새로운 대상의 추출이고, 경험적 종합은 과거의 학습 경험과 이에 대한 활용을 통한 대상의 추출이다. 이러한 분류를 기초로 하여 초등학교 교과서에 제시된 문제를 통해 실제 적용하여 탐색하였다.

• 한국정밀공학회지
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• 제11권6호
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• pp.65-74
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• 1994

Various substructure synthesis methods, such as component mode synthesis, building block analysis and reduced impedance method, are studied for the determination of vibration characteristics of plate problems. Comparisons are made for each methods in terms of accuracy and computational efficiency. Following conclusions are made from the results of computer simulations and experiments. i) The computation time of component mode synthesis is much shorter than that of whole structure analysis. The natural frequencies of lower modes obtained from component mode synthesis are almost same as those obtained from whole structure analysis, but in higher modes the differences between those two methods are increases. ii) The transfer function obtained from building block analysis is same as that obtained from the finite element method. iii) Same transfer functions can be obtained by the reduced impedance method. The computation time of reduced impedance mathod is shorter that that of general finite element method, but for the solutions in broad frequency band it requires long calculation time.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1996년도 추계학술대회논문집; 한국과학기술회관, 8 Nov. 1996
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• pp.118-123
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• 1996

The purpose of this study is to develop acoustic substructure synthesis method that can be applied to acoustic modal analysis of complex acoustic systems. Acoustic modal analysis method to be introduced here is a method that analyze acoustic natural mode shape of the complex acoustic system by the principle of CMS(component mode synthesis method). This paper describes the acoustic modal analysis of the acoustic finite element model of simple expansion pipe by acoustic substructure synthesis method. The results of acoustic modal analysis analyzed by Acoustic substructure synthesis method and the results, by FEM(finite element method) shows good agreement.

• 소음진동
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• 제8권1호
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• pp.139-145
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• 1998

A great deal of effort has been invested in upgrading the performance and the efficiency of dynamic analysis of mechanical structures. Using experimental modal analysis(EMA) or finite element analysis(FEA) data of mechanical structures, the performance and efficiency can be effectively evaluated. In order to analyze complex structures such as automobiles and aircrafts, for the sake of computing efficiency, the dynamic substructuring techniques that allow to predict the dynamic behavior of a structure are widely used. Through linking a modal model obtained from EMA and an analytical model obtained from FEA, the best conditioned strucutres can be proposed. In this study, a new algorithm of substructre synthesis method, Multi-FRF synthesis method, is proposed to analyze a structure composed of many substructures.

• 한국수학교육학회지시리즈E:수학교육논문집
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• 제20권2호
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• pp.231-248
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• 2006

수학적인 사고에는 여러가지 유형이 있는데 그 중에서 가장 기본이 되는 사고유형이 분석과 종합이다. 이러한 사고유형을 담고 있는 분석과 종합문제는 수학문제의 가장 중요한 근간이라고 할 수 있다. 이러한 분석과 종합문제에 대한 체계적인 분석과 구체적인 논의를 위해 러시아의 구세프 교수가 편찬한 수학교과서를 중심으로 이러한 두 가지 유형의 문제에 대한 분석을 실시한다. 또한, 역사적으로 제시되어진 분석과 종합에 대한 다양한 문헌연구를 통해 두 가지 사고유형의 분류에 대한 기본적인 기준을 설정하고, 이를 바탕으로 분석문제와 종합문제에 대한 구체적인 분류기준을 제시하고자 한다.

• Advances in nano research
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• 제10권1호
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• pp.71-76
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• 2021

Synthesis of nanoparticles using green technology using plants is gaining significant attention as it is an environmentally friendly substitute to conventional physical and chemical methods. The present study was focused on the chemical and green synthesis of Iron Oxide nanoparticles from ferric chloride. The green synthesis was achieved by utilizing the bio components of Hibiscus rosa-sinensis. The Fe3O4 nanoparticles with the size range of 87-400 nm were synthesized by wet chemical reduction technique which are unstable, prone to aggregation while in green synthesis the phytochemicals present in the leaf extract acts as the capping as well as the reducing agent thus the green synthesized iron (III) oxide nanoparticles were naturally stabilized, spherical shaped and are in the size range of 2-80 nm. The results of both the protocols are compared and presented briefly.

• Nuclear Engineering and Technology
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• 제51권1호
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• pp.163-169
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• 2019

The robust controller synthesis and analysis of the water level process in the U-tube system generator (UTSG) is addressed in this paper. The parameter uncertainties of the steam generator (SG) are modeled as multiplicative perturbations which are normalized by designing suitable weighting functions. The relative errors of the nominal SG model with respect to the other operating power level models are employed to specify the weighting functions for normalizing the plant uncertainties. Then, a robust controller is designed based on ${\mu}$-synthesis and D-K iteration, and its stability robustness is verified over the whole range of power operations. A gain-scheduled controller with $H_{\infty}$-synthesis is also designed to compare its robustness with the proposed controller. The stability analysis is accomplished and compared with the previous QFT design. The ${\mu}$-analysis of the system shows that the proposed controller has a favorable stability robustness for the whole range of operating power conditions. The proposed controller response is simulated against the power level deviation in start-up and shutdown stages and compared with the other concerning controllers.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.391-393
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• 2004

For performance and stability of a synchronized system, we need an efficient Clock Tree Synthesis(CTS) methodology to design clock distribution networks. In a system-on-a-chip(SOC) design environment, CTS effectively distributes clock signals from clock sources to synchronized points on layout design. In this paper, we suggest the pre-layout analysis of the clock network including gated clock, multiple clock, and test mode CTS optimization. This analysis can help to avoid design failure with potential CTS problems from logic designers and supply layout constraints so as to get an optimal clock distribution network. Our new design flow including pre-layout CTS analysis and structural violation checking also contributes to reduce design time significantly.