• 산업공학
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• 제1권1호
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• pp.17-26
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• 1988

This paper describes a nonlinear goal programming approach to the optimal composition of composite solid propellant taking multiple characteristics into consideration synchronously. The nonlinear goal programming model with response functions, restrictions and the optimal value of each characteristic is developed using Scheffe's "Experiments with mixtures" and preference weighting system. Objective functions are described based on process, performance and assurance characteristics. The systematic approach to optimal composition in this study is proved efficient through a CTPB-AL-AP propellant which is one of composite solid propellant systems.

• 정보과학회 컴퓨팅의 실제 논문지
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• 제23권12호
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• pp.698-702
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• 2017

자연 언어 처리(Natural Language Processing) 분야에 심층 신경망(Deep Neural Network)이 소개된 이후, 단어, 문장 등의 의미를 나타내기 위한 분산 표상인 임베딩(Embedding)을 학습하기 위한 연구가 활발히 진행되고 있다. 임베딩 학습을 위한 방법으로는 크게 문맥 기반의 텍스트 모델링 방법과, 기학습된 임베딩을 결합하여 더 긴 텍스트의 분산 표상을 계산하고자 하는 결합 기반의 텍스트 모델링 방법이 있다. 하지만, 기존 결합 기반의 텍스트 모델링 방법은 최적 결합 단위에 대한 고찰 없이 단어를 이용하여 연구되어 왔다. 본 연구에서는 비교 실험을 통해 문서 임베딩 생성에 적합한 결합 기법과 최적 결합 단위에 대해 알아본다. 또한, 새로운 결합 방법인 담화 분석 기반의 결합 방식을 제안하고 실험을 통해 기존의 순차적 결합 기반 신경망 모델 대비 우수성을 보인다.

• 대한수학회보
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• 제59권6호
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• pp.1327-1337
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• 2022

Zero-difference balanced (ZDB) functions can be applied to many areas like optimal constant composition codes, optimal frequency hopping sequences etc. Moreover, it has been shown that the image set of some ZDB functions is a regular partial difference set, and hence provides strongly regular graphs. Besides, perfect nonlinear functions are zero-difference balanced functions. However, the converse is not true in general. In this paper, we use the decomposition of cyclotomic polynomials into irreducible factors over 𝔽_p, where p is an odd prime to generalize some recent results on ZDB functions. Also we extend a result introduced by Claude et al. [3] regarding zero-difference-p-balanced functions over 𝔽_pⁿ. Eventually, we use these results to construct some optimal constant composition codes.

• 한국정밀공학회지
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• 제15권6호
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• pp.79-89
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• 1998

In determining optimal cutting condition for face milling operation, tool wear is an important factor. For the purpose of establishing the relationship between various machining factors and tool wear, cutting tests have been performed. As a result, hardness and chemical composition of workpiece material, chemical composition and grain size of cutting tool and cutting speed have been selected as machining factors. In addition, relationship between feed rate and workpiece hardness has been observed. Prior to utilizing cutting conditions recommended by ‘Machining Data Handbook(MDH)’ as a knowledge base, an analysis for the validity of the MDH has been provided. Based on this analysis, tool life criteria applied by MDH has been modified. Finally, using MDH recommended data for neural network trainning, the results from the trained neural network for optimal cutting condition for some given workpiece and cutting tool can be used as reference cutting conditions.

• 전기학회논문지
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• 제65권6호
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• pp.962-968
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• 2016

The large scaled lead-acid battery is widely used for efficient operation of the photovoltaic system in many islands. However, lithium-ion battery is now being introduced to mitigate the fluctuation of wind power and to replace lead-acid battery. Therefore, hybrid ESS(Energy Storage system) that combines lithium-ion battery with lead-acid battery is being required because lithium-ion battery is costly in present stage. Under this circumstance, this paper presents the optimal algorithm to create composition rate of hybrid ESS by considering fixed and variable costs in order to maximize advantage of each battery. With minimization of total cost including fixed and variable costs, the optimal composition rate can be calculated based on the various scenarios such as load variation, life cycle and cost trend. From simulation results, it is confirmed that the proposed algorithms are an effective tool to produce a optimal composition rate.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(5)
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• pp.149-152
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• 2002

The aim of this study is to analyse the problems occurred by using classical algorithm to synthesize the H$\infty$ optimal controller. The obtained result of analysis applied to the composition of algorithm for the new H$\infty$ optimal controller which was introduced in this study. The study investigates and compares H$\infty$ optimal controller formed by new algorithm with the one formed by classical algorithm. In particular, robustness related to the robust control is systematically described by using the composition of algorithm for the classical H$\infty$ optimal controller. In addition, the flow charts classified into classical algorithm and new one are discussed to synthesize the H$\infty$ optimal controller.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.736-738
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• 2005

For calculating optimal generation composition of The Basic Plan of Long Term Electricity Supply & Demand, the Screening Curve Method that using generation cost for planning is needed. This paper will induce optimal power system ratio included Combined Head and Power and suggest the method for optimal generation composition of The Basic Plan of Long Term Electricity Supply & Demand that considered policy side.

• Food Science and Biotechnology
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• 제17권6호
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• pp.1151-1155
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• 2008

This study aimed to investigate the alterations in plasma antioxidant activity after the consumption of a single oral dose of curcumin, vitamin C, and E administered individually or in combination to (i) assess possible synergies or antagonism between the antioxidants and (ii) determine the optimal composition of the antioxidant mixture such that the duration of action is prolonged to beyond that of individual antioxidants. Each antioxidant was administered to male Sprague-Dawley rats, and blood samples were drawn at different time points up to 180 min to measure the plasma total antioxidant capacity (TAC). Five antioxidant compositions (M1-M5) were evaluated to assess the possible synergies or antagonisms among them and to determine the optimal composition of the antioxidant mixture. Blood samples were collected up to 360 min post-consumption. A single oral dose of individual antioxidants significantly increased the TAC values; however, the time to reach the peak TAC value varied. Among the 5 antioxidant compositions, M2 exhibited the highest and most prolonged antioxidant effect in plasma; this was greater than the proportional sum of the effects of the individual antioxidants in the composition. This result indicates a synergistic interaction among antioxidants in the optimal composition M2.

• 공업화학
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• 제32권5호
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• pp.574-580
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• 2021

최고 품질의 클렌징 제품 개발을 위해서 계면활성제 혼합물 조성의 최적화를 시도하였다. 사전실험을 통해 세정력, 기포형성력, 오염률에서 각각 우수한 특성을 나타내는 계면활성제 3종 sodium cocoyl alaninate (SCoA), cocamidopropyl betaine (CPB), decyl glucoside (DG)을 선정하였다. 계면활성제 혼합물의 심플렉스 중심 설계 배열에 따른 실험을 수행하고, 실험에서 얻어진 데이터를 가지고 회귀분석을 실시하였다. 통계적으로 유의미한 반응 표면 모델식을 구하고, 세 개의 반응변수의 동시 최적화 과정을 통해 계면활성제 혼합물의 최적 조성은 SCoA (0.22), CPB (0.78), DG (0.00)으로 구해졌다.

• KEPCO Journal on Electric Power and Energy
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• 제2권1호
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• pp.49-54
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• 2016

현재 대부분의 도서지역에서는 태양광발전을 효율적으로 운용하기 위하여 대용량 연축전지가 많이 사용되고 있지만, 풍력발전의 도입, 축전지 교체로 인하여 리튬이온전지의 도입이 증가하고 있다. 따라서 본 논문에서는 기존에 많이 보급되어 사용되고 있는 연축전지와 리튬이온전지의 장점을 최대한 활용하기 위하여, 연축전지와 리튬이온전지용 하이브리드 ESS의 최적 운용평가를 할 수 있는 알고리즘을 제시하였다. 상기의 알고리즘을 이용하여 시뮬레이션을 수행한 결과, 각 전지의 도입비용과 운용비용이 최소화 되는 운용조건에서 최적구성비를 산출하였다. 이에 따라 본 논문에서 제안한 하이브리드 ESS의 최적구성 알고리즘에 대한 유용성을 확인하였다.