• 자원ㆍ환경경제연구
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• 제14권1호
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• pp.135-166
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• 2005

본 연구의 목적은 한국의 24개 광업과 제조업종을 대상으로 1995~1999년간 통합된 오염원단위 지수와 변화지수를 제시하고 이를 통하여 환경성과를 측정하고자 함이다. 본 연구는 오염원단위의 새로운 정의와 통합된 오염원단위를 측정하는 새로운 기법을 제시한다. 광업과 제조업을 경공업, 중공업 그리고 중공업내 오염산업과 여타중공업으로 구분하고 실증적으로 통합원단위 지수와 변화지수를 계측한다. 통합오염원단위 지수 기준으로 중공업내 오염산업은 가장 오염집약적인 업종인 반면, 같은 중공업내 여타 중공업에 속한 업종은 가장 오염저감에 성공적이다. 통합오염원단위 변화지수를 기준으로 산업 전체의 평균치는 1,091로서 오염배출량변화지수가 1.133으로 연간 13.3% 증가한 반면 산출량변화지수는 1.039로 연간 3.9% 증가하여 약 9.1% 상승하였다. 경공업과 중공업의 통합원단위 변화지수는 각각 1.125와 1.042였고, 오염산업의 평균이 1.287로 가장 높았음에도 중공업의 평균이 낮았던 것은 역시 여타 중공업의 평균이 0.913으로 연간 약 9% 가량 감소하였기 때문이다.

• 기술혁신연구
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• 제20권3호
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• pp.29-55
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• 2012

본 연구는 BSC의 성공적 구축과 활용에 있어 최근 변화하는 경영환경에 적절하게 대응하고, 기업의 경영활동에서 비재무적 요소가 차지하는 중요성을 감안하여 무형적 자원의 대표적 요소인 R&D 지출과 관련하여 BSC의 KPI를 개발하고, 개발된 지표의 효용성을 실증분석을 통해 검정하고자 하였다. 본 연구를 통해 BSC의 KPI로써 개발된 PEI(Patent Efficiency Index)는 R&D 지출과 R&D의 output 개념인 특허와의 상관성을 고려하여 특허의 효율성 측면에서 만들어 졌으며, 기존의 R&D관련 KPI가 가진 문제점을 해결하고, R&D 성과측정에 관한 새로운 KPI개발을 시도하였다는 점에서 연구적 의의가 있다고 하겠다. 또한 지표의 효용성에 대한 실증분석 결과, 논문의 관심변수인 PEI는 종속변수인 기업경영성과의 대용치로 나타내어진 ROA(총자산이익률)과 토빈Q에 각각 유의한 양의 영향을 미치는 것으로 나타났으며 그동안 기존 연구들에서 많은 관심을 가져왔던 R&D 지출보다 R&D의 성과측정지표로서의 설명력이 더 높은 것으로 나타났다. 이상 결과를 통해 개발된 PEI는 기존의 R&D 지출이 기업성과에 미치는 영향을 설명하는데 있어 설명하지 못하는 추가적인 설명력을 가진다고 할 수 있다. 나아가 이 지표를 통해 기업이 얼마나 효율적인 R&D 활동을 하고 있는지 알 수 있으며, 이는 기업의 R&D 활동의 효율성이 높을 때 기업의 가치나 성과가 높아진다는 것을 시사한다. 본 연구는 기업의 R&D 지출과 기업경영성과 간의 관련성을 특허와 R&D 지출의 효율적인 측면을 측정한 PEI를 통하여 직접적으로 입증함으로써 기존의 R&D 비용 외에 기업의 기업경영성과를 가늠하고 판단할 수 있는 중요한 지표로 쓰일 수 있다는 것을 규명할 수 있을 것으로 기대된다.

• 대한전자공학회논문지SD
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• 제41권9호
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• pp.31-37
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• 2004

oxide 층의 위치와 두께 조절을 통하여 oxide-VCSEL이 단일모드로 동작하는 활성영역의 반경을 확장하는 방법을 Self-consistent effective-index 방법을 이용하여 제시하였다. 이렇게 활성영역이 넓어지면 고속, 고신뢰도, 고출력 동작에 유리한 단일모드 VCSEL을 만들 수 있게 된다. 고출력을 위하여 단일모드로 동작하는 활성영역을 확대하는 방법을 하면 다음과 같다. 첫째 oxide 층은 활성층에서 멀리 떨어진 곳에 위치시켜야 한다 둘째, oxide 층은 얇게 만들어야 한다. 셋째, oxide층을 node에 위치시켜야 한다. 그리고 고출력을 위하여 p-DBR 쌍의 수를 줄이는 것은 단일모드 동작조건을 변화시키지 않는다. 이 방법을 사용하면 단일모드로 동작하는 oxide-aperture 크기를 3m% 이상 키울 수 있다.

• 산경연구논집
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• 제10권2호
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• pp.7-15
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• 2019

Purpose - The industrial structure upgrading can play an important role in promoting the carbon emission efficiency. Thus, this paper attempts to study the impact of industrial structure upgrading on carbon emission efficiency in order to reduce carbon emissions. Research design, data, and methodology - This paper selects panel data of 30 provinces and municipalities (autonomous regions) in China from 2001 to 2016, and divides them into three regions. The Moore index is used to measure the industrial structure upgrading, the non-radial SBM model based on undesired output is used to measure the slack variable to calculate the total factor carbon emission efficiency. Finally the impact of industrial structure upgrading on the carbon emission efficiency are analyzed. Results - It is found that the Moore index and the carbon emission efficiency in the eastern region is the highest in the three regions. Conclusions - The influence of various influencing factors on carbon emission efficiency is different between regions. The Moore index has a positive effect on the carbon emission efficiency in the eastern region, and has a negative influence coefficient on the central region. The effect on the western region is not obvious.

• 한국정밀공학회지
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• 제16권12호
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• pp.152-160
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• 1999

The weld quality of $CO_2$ arc welding is closely related to the arc stability. As the characteristics of the arc are excessively complex and nonlinear, it is not easy to make the arc model as mathematical form and to control the arc state to be stabilized. This paper was aimed to estimate the arc stability and to control for stabilizing the arc state in short circuit metal transfer mode of $CO_2$ arc welding. For these purposes, the behaviors of arc stability was investigated at different welding conditions using Mita's arc stability index, and the fuzzy control algorithm which uses the arc stability index as control imput and the arc voltage as control output was developed. In the control of the arc stability, the experiments of two cases were performed; the case of setting an initial welding voltage arbitrarily, the case of the step change in workpiece shape. Obtained results were as follows; Mita's arc stability index was able to be estimated qualitatively in the case of using the inverter type welding power source and the control performance for stabilizing the arc status was excellent in the case of existing step change disturbance.

• 보건의료산업학회지
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• 제10권2호
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• pp.15-23
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• 2016

Objectives : The purpose of this study was to evaluate the productivity changes of 18 public health centers in Gangwon-do from 2006 to 2013 using the Malmquist Productivity Index(MPI). Methods : Data were collected from Statistics Korea from 2006 to 2013. The input variables were the numbers of medical, nursing and administrative personnels. The output variables were the performances of health promotion programs. Along with the traditional input-oriented DEA analysis, the MPI was calculated. Results : First, among the 18 public health centers, the productivity index of 14 public health centers was increased. Second, the annual productivity showed a 6% increase. Third, the productivity improvements were mainly caused by Scale Efficiency Change. Conclusions : Improving the productivity of public health centers requires the support and external policies of the national and local government. Internally, public health centers need to maintain scale optimization of the center. Additionally, efforts should be made to effectively use limited resources.

• 수산경영론집
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• 제43권2호
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• pp.95-106
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• 2012

This study analyzed the changes in productivity growth of 291 regional fisheries cooperatives area from 2001 to 2010 selected as target. The productivity growth analysis of operating offices calculates Global-Malmquist productivity index. Input variables are number of the persons and the nettable area, output variables are deposit, loans and earnings. To improve the homogeneity of industry, the operating conditions were considered. Global Malmquist index of Operating offices was reduced between 2001~2010. The cause of increase and decrease of productivity are divided by efficiency change(EC) and best-practice change(BPC). Operating offices with increased productivity existed between 2001~2002 and between 2002~2003 and between 2006~2007. There were operating offices with increased productivity by EC. Global Malmquist index of Operating offices with locations was highest relatively in metropolitan. Operating offices with increased productivity existed between 2003~2004 and between 2007~2008 and between 2008~2009 in all locations. There were operating offices with decreased productivity by BPC.

• 전기학회논문지
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• 제62권3호
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• pp.355-364
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• 2013

Respect to the input AC voltage and output DC voltage, conventional three-phase PWM rectifier is classified as the voltage type rectifier with boost capability and the current type rectifier voltage with buck capability. Conventional PWM rectifier can not at the same time the boost and buck capability and its bridge is weak in the shoot- through state. These problems can be solved by Z-source PWM rectifier which has all characteristic of voltage and current type PWM rectifier. By shoot-through duty ratio control, the Z-source PWM rectifier can buck and boost at the same time, also, there is no need to consider the dead time. This paper proposes the input AC voltage sensorless control method of a three-phase Z-source PWM rectifier in order to accomplish the unity input power factor and output DC voltage control. The proposed method is estimated the input AC voltage by using input AC current and output DC voltage, hence, the sensor for the input AC voltage detection is no needed. comparison of the estimated and detected input AC voltage, estimated phase angle of the input voltage, the output DC voltage response for reference value, unity power factor, FFT(Fast Fourier Transform) of the estimated voltage and efficiency are verified by PSIM simulation.

• International Journal of Knowledge Content Development & Technology
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• 제10권2호
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• pp.51-69
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• 2020

This paper describes global research in the field of augmented reality (22078) as indexed in Scopus database during 1992-2019, using a series of bibliometric indicators. The augmented reality (AR) research registered high 54.23% growth, averaged citation impact of 8.90 citations per paper. Nearly 1% of global output in the subject (226 papers) registered high-end citations (100+) per paper. The top 15 countries accounted for 87.05% of global publications output in the subject. The USA is in leadership position for its highest publications productivity (19.25% global share). The U.K. leads the world on relative citation index (2.05). International collaboration has been a major driver of AR research pursuits; between 11.89% and 44.04% of national share of top 15 countries in AR research appeared as international collaborative publications. AR research productivity by application types was the largest across sectors, such as education, industry and medical. Computer science has emerged as the most popular areas in AR research pursuits. Technical University of Munich, Germany and Osaka University, Japan have been the most productive organizations and Nara Institute of S&T, Japan (66.55 and 7.48) and Imperial College, London, U.K. (57.14 and 6.42) have been the most impactful organizations. M. Billinghurst and N. Navab have been the most productive authors and S. Feiner and B. MacIntyre have been the most impactful authors. IEEE Transactions on Visualization & Computer Graphics, Multimedia Tools & Applications and Virtual Reality topped the list of most productive journals.

• 대한기계학회논문집
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• 제18권8호
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• pp.1985-1996
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• 1994

A new design method of sliding hyperplanes is proposed in the synthesis of a variable structure controller for robust tracking of general nonlinear multi-input-output(MIMO) uncertain systems of relative degree higher than two. Input/ output(I/O) linearzation is firstly undertaken by employing the concept of relative degree and minimum phase followed by the construction of sliding mode controllers. Sliding hyperplanes are then derived from the inherent properties of companion matrix and ideal sliding mode characterized in I/O linearized system. Subsequently, the gradient magnitudes of the sling hyperplanes are determined in an optimal manner by considering a quadratic performance index to be evaluated at two phases; a reaching phase and a sliding phase. The proposed design methodology is relatively straightforward and systematic compared with conventional strategies such as geometric approach or pole assignment technique. A nonlinear governor and exciter control problem for a power system is adopted herein in order to demonstrate the design efficiency and also favorable and robust control performances.