• 자원ㆍ환경경제연구
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• 제15권4호
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• pp.643-672
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• 2006

본 연구는 한국의 산업별 독성물질 배출량을 이용하여 산업별 인체유해도를 측정한 것이다. 분석에 이용된 자료는 146종의 인체유해화학물질 배출량과 2000년도 산업연관표이다. 분석결과, 총배출 강도가 높은 산업의 순위는 목재나무제품펄프종이(1.1632) >유기화학기초제품(0.9750) >기타화학제품(0.9620) >플라스틱제품(0.3804) >합성수지 및 합성고무(0.3412) >선박 및 기타 수송장비(0.3275) 등이다. 또한 인체발암지수는 산업 전체가 $11.86198{\times}10^3$(이미지참조)이며, 산업 평균이 $0.26360{\times}10^3$(이미지참조)으로 계산되었다. 인체유해도가 높은 산업의 순위를 보면, 자동차 및 부문품(7.85033) >선철 및 강반성품(4.57409) >철강 1차 제품(4.36668) >선박 및 기타 수송장비(3.43293) >무기화학기초제품(2.64379) 등이다. 총배출강도나 인체유해도 등은 인체유해 화학물질 감축을 위한 수요 및 산업 정책을 전개할 때, 규제산업의 우선순위를 결정하는 근거가 될 수 있다.

• 한국세라믹학회지
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• 제42권3호
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• pp.178-181
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• 2005

Silicon oxynitride (SiON) 막은 플라즈마 화학기상증착법(PECVD)으로 $SiH_4,\;N_2O$와 $N_2$ 가스를 사용하여 $SiO_2/Si$ 위해 증착되었다. 증착 변수에 따라서 SiON 막의 굴절률은 prism coupler를 사용하여 1552nm 파장에서 $1.4480\~1.4958$까지 변화하였다. 평판 광도파로 코어로 사용되는 SiON 막의 두께는 $6{\mu}m$이고, buffer 막과의 굴절률 차이(An)는 $0.36\%$이다. 또한 식각 공정으로 $SiO_2$ 막 위에 증착된 SiON 막은 건식식각을 통해서 수행되었다. 광화이버에 $1.55{\mu}m$ 파장의 레이저론 입력단에 조사하였다. 결과적으로 저굴절률 차이 SiON 광도파로를 제작하였으며, 출력단에서 single-mode 형상을 확인하였다.

• 대한전기학회논문지:전력기술부문A
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• 제48권9호
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• pp.1140-1146
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• 1999

In this paper, a force estimation method is proposed for force control without force sensor. For this , a disturbance observer is applied to each joint of an {{{{ { n}_{ } }}}} degrees of freedom manipulator to obtain a simple equivalent robot dynamics(SERD) being represented as an n independent double integrator system. To estimate the output of disturbance observer due to internal torque, the disturbance observer output estimator(DOOE) is designed, where uncertain parameters of the robot manipulator are adjusted by the gradient method to minimize the performance index which is defined as the quadratic form of the error signal between the output of disturbance observer and that of DOOE. when the external force is exerted, the external force is estimated by the difference between the output of disturbance observer and DOOE, since output of disturbance observer includes the external torque signal as well as the internal torque estimated by the output of DOOE. And then, a force controller is designed for force feedback control employing the estimated force signal. To verify the effectiveness of the proposed force estimation method, several numerical examples and experimental results are illustrated for the 2-axis direct drive robot manipulator.

• 수산경영론집
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• 제41권3호
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• pp.21-44
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• 2010

The paper estimates changes in total factor productivity and technical efficiency change index and technical change index using Malmquist productivity index(MPI) in fisheries wholesale products over the time period of 2006 through 2008. The model considers a number of employees and operating costs as input factors, and sales and EBIT(earnings before tax and interest) as output factors. The results indicate that, between 2006 and 2007, there is in general technical progress in which TCI(Technical Change Index) indicates 2.7994 in the sale scale of 50 million won through 100 million won, while there are no efficiency in TECI(Technical Efficiency Change Index), PECI(Pure Efficiency Change Index) and SECI(Scale Efficiency Change Index) which are estimated to be around 1. Between 2007 and 2008 technical efficiency and technical progress are generally declined, compared to those of 2006 and 2007. Wilcoxon's rank-sum test shows that there are statistically significant difference of TCI and MPI between two periods at the level of 5%, while there are statistically significant difference of TECI, PECI and SECI between two periods at the level of 5%.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2000년도 추계정기학술대회:지능형기술과 CRM
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• pp.427-436
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• 2000

The prediction of stock price index is a very difficult problem because of the complexity of the stock market data it data. It has been studied by a number of researchers since they strong1y affect other economic and financial parameters. The movement of stock price index has a series of change points due to the strategies of institutional investors. This study presents a two-stage forecasting model of stock price index using change-point detection and artificial neural networks. The basic concept of this proposed model is to obtain Intervals divided by change points, to identify them as change-point groups, and to use them in stock price index forecasting. First, the proposed model tries to detect successive change points in stock price index. Then, the model forecasts the change-point group with the backpropagation neural network (BPN). Fina1ly, the model forecasts the output with BPN. This study then examines the predictability of the integrated neural network model for stock price index forecasting using change-point detection.

• 한국융합학회논문지
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• 제5권4호
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• pp.163-169
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• 2014

A stable neural network control scheme for unknown non-linear systems is developed in this paper. While the control variable is optimised to minimize the performance index, convergence of the index is guaranteed asymptotically stable by a Lyapnov control law. The optimization is achieved using a gradient descent searching algorithm and is consequently slow. A fast convergence algorithm using an adaptive learning rate is employed to speed up the convergence. Application of the stable control to a single input single output (SISO) non-linear system is simulated. The satisfactory control performance is obtained.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2009년도 정기총회 및 추계학술대회 논문집
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• pp.225-227
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• 2009

본 논문에서는 전압형 3상 ZSI(Z-source Inverter)의 입력전압과 커패시터 충전전압을 검출하고 ZSI의 기본 정의를 이용해 지령전압에 대한 변조지수(Modulation Index)를 결정하는 방법과 출력전압 제어가 가능한 변형된 SVM(공간벡터 변조방식)으로 구성된 알고리즘을 소개한다. 제안된 알고리즘은 ZSI의 이득과 변조지수의 정의를 이용한 간단한 방법으로 변조지수를 변화시켜 출력전압을 일정하게 유지하는 방법이다. PSIM을 통하여 타당성을 입증하였다.

• Journal of Korea Trade
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• 제27권5호
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• pp.113-136
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• 2023

Purpose - Global production chains and their impacts on economic growth have drawn extensive attention from researchers. Close relationships among global production chains, export and economic growth have been illuminated, as evidenced by the fast and stable economic growth of East Asian economies. These economies perform various roles within global production chains using offshoring, in which the impact of import on domestic gross output is as strong as that of export. The impact of import on economic growth would depend on whether imported inputs substitute or complement domestic inputs production, which is likely to vary according to individual countries' functions within global production chains. The economic growth of concerned countries would also be diverse. However, little attention has been paid to the impact brought by imports compared to its significance. Design/methodology - The principal methodology used in this paper is structural decomposition analysis (SDA), widely chosen to elucidate the impact of various factors on domestic gross output using input-output tables. This paper extracts trade data of six Asian economies from the World Input-Output Database (WIOD) 2016 release that covers 43 countries for the period 2000-2014. The extracted data is then categorised into 37 sectors. First, this paper calculates the Feenstra-Hanson Offshoring Index (OSI) of each country. It then applies SDA to measure the changes in each economy's gross output, export, import input coefficients, and domestic input coefficients. Finally, after taking the first difference from pooled time-series data, it estimates the correlations between imported input coefficients and OSI using the ordinary least square (OLS) method. Findings - The main findings of this paper can be summarised as follows. Firstly, all six countries have increasingly engaged in global production chains, as evidenced by the growing size of OSI. Secondly, there are negative correlations in five countries except Japan, with sectoral differences. Thirdly, changes in import input coefficients are not negative in all six countries, indicating that offshoring does not necessarily substitute for domestic inputs production but does complement it and, therefore, fosters their economic growth. This is observed in China, Indonesia, Korea and Taiwan. Offshoring has led to an increase in the use of imported inputs, which has, in turn, stimulated domestic inputs production in these countries. Originality/value - While existing studies focus on the role of export in evaluating the impact of participating global production chains, this paper explicitly examines the unexplored impact of import on domestic gross output by considering both the substitution and the complementary effect, using the WIOD. The findings of this paper suggest that Asian economies have achieved fast and stable economic growth not only through successful export management but also through effective import management within global production chains. This paper recommends that the Korean government and enterprises carefully choose offshoring strategies to minimise disruption to domestic production chains or foster them.

• 자원ㆍ환경경제연구
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• 제15권3호
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• pp.425-450
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• 2006

산업부문은 생산 활동을 담당하는 특성 때문에 많은 에너지를 소비하고 많은 $CO_2$를 배출한다. 산업부문 중에서 에너지다소비산업이라고 일컬어지는 산업들은 다른 산업에 비해서 에너지소비가 많고 $CO_2$ 배출을 많이 하므로 관련정책의 목표대상으로서 우선적으로 거론된다. 그러나 해당 산업의 생산액과 $CO_2$ 배출량을 사용하는 환경원단위는 해당 산업만의 환경오염물질 배출의 정도를 측정하기에는 적합하지만, 산업들이 유기적으로 연결되어 서로 생산품을 수요하고 공급하고 있는 점을 고려한다면 환경원단위를 확대시킨, 그리고 산업 전체를 고려하는 지표로 해당 산업의 환경물질의 배출 정도를 평가해야 한다. 이에 본 논문에서는 우리나라의 환경산업연관표 2000을 작성하고, 에너지다소비산업 외에 전 산업을 대상으로 하여 산출액기준 및 열량기준의 환경원단위와, 이를 보다 확대하고 산업의 유기적 관계까지를 모두 고려하는 유발 $CO_2$ 발생량을 추정하여 우리나라의 경제주체간 및 산업간의 상품생산과 흐름에 수반되는 에너지소비와 환경오염물질의 흐름을 분석하였다. 분석결과에 따르면 산출액기준 및 열량기준의 환경원단위가 상대적으로 높은 산업들의 유발 $CO_2$ 발생량은 크다. 이 산업들은 직접적으로 발생시키는 $CO_2$가 많은 산업들이며, 환경부하가 큰 재화나 서비스를 생산한다. 그러므로 이 산업들을 대상으로 환경원단위 저감을 유도한다면 $CO_2$ 발생량을 감소시킬 수 있다. 그러나 환경원단위가 낮은 산업의 생산 시에 환경원단위가 높은 산업들의 생산품이 투입재로 사용된다면 그 산업의 유발 $CO_2$ 발생량은 커지고 경제 전체의 환경부하를 크게 만든다. 따라서 산출액기준의 환경원단위가 높은 산업들만을 중심으로 하여 환경원단위를 저하시키는 것 외에, 낮은 환경원단위를 갖는 산업들의 환경원단위도 지속적으로 감소시켜 다른 산업에 대한 연관을 통한 유발 $CO_2$ 발생량을 감소시켜야 한다. 이는 모든 산업에 대한 지속적인 환경원단위 저감이 경제 전체를 기준으로 더 큰 $CO_2$ 발생량 저감을 유도하는 것을 의미한다.

• 센서학회지
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• 제32권4호
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• pp.223-231
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• 2023

An integrated-optical biochemical sensor structure that can perform homogeneous and surface sensing using a 2×2 balanced-bridge Mach-Zehnder interference structure based on the optimized SOI slot optical waveguide was described, and its performance and characteristics were evaluated. Equations for the two output optical powers were derived and examined using the transfer matrices of a 3-dB coupler and phase shifter (channel waveguide). The length of the 3-dB coupler was determined such that the two output optical powers were same using these formulas. In homogeneous sensing, the effect of the refractive index of an analyte in the range of 1.33-1.36 on the two output optical power distributions was numerically derived, and the sensitivity was calculated based on each output and the difference between the two outputs, the former and the latter being 7.5796-19.0305 [au/RIU] and 15.2601-38.1351 [au/RIU], respectively. In the case of surface sensing, the sensitivity range of the refractive index of 1.337 based on each of the two outputs was calculated as -2.2490--3.5854 [au/RIU] and 1.2194-3.8012 [au/RIU], and the sensitivity range of 4.8048-7.0694 [au/RIU] was confirmed based on the difference between the two outputs.