• Korean Journal of Optics and Photonics
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• v.17 no.5
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• pp.455-460
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• 2006

The output characteristics of a ceramic Nd:YAC laser pumped by a fiber-coupled laser diode was investigated. An efficiency and a slope efficiency of 33.8 % and 39.3 % respectively were obtained, under an output coupler reflectance of 90.4 %. The laser power has decreased suddenly due to the thermal tensing effect more than 6 W pumping powers.

• Journal of Digital Convergence
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• v.12 no.6
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• pp.203-213
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• 2014

The purpose of this research is to deduce the effects factor of R&D output and outcome in the aspect of the researcher's intellectual property capacity, and conduct an empirical analysis to see if there is intermediated effect between cooperation of a patent attorney and output. I applied three step, input (researcher's intellectual property capacity and intellectual property environment), output (number of patent and SCI paper), outcome (number of technology transfer, profit), and analyzed the effects of researcher's intellectual property factors on output and outcome through structural equation model. The results are as follows. First, there's no cooperation between a researcher and patent attorney, the researcher's knowledge on patent specification had direct effect on the output. Second, a researcher and an patent attorney cooperate, the cooperative activities have complete mediation effect on the output, and the researcher's will to commercialize the technology has direct effects on the output. Third, the intellectual property environment of the research organization gives direct effects on the researcher's intellectual property capacity, and gives indirect effects on the outcome. this study suggest that it is important to cooperate with external experts in order to excellent R&D outcome.

• The Transactions of the Korean Institute of Power Electronics
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• v.24 no.4
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• pp.273-278
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• 2019

This study proposes a method for improving the overmodulation performance of a three-phase inverter to obtain an enhanced output torque for the AC motors. In the inverter-fed AC motor drives, the output torque of the motor can be enhanced by utilizing the overmodulation region as well as the linear modulation regions of the inverter. The overmodulation method is used for this overmodulation operation of the inverter. However, the voltage gain, the ratio of the output voltage of the inverter to the reference voltage achieved by the conventional overmodulation methods becomes nonlinearly smaller than unity. Therefore, the effect of improving the output torque of the AC motors is insignificant even when the overmodulation region is utilized. In this study, we propose a method that improves the overmodulation performance of the inverter by compensating the limited amount of the reference voltage in the overmodulation operation to enhance the output torque of the AC motors. The effectiveness of the proposed method is verified through the simulations and experiments with an 800 W permanent magnet synchronous motor.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.2
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• pp.231-236
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• 2012

This work presents the application of the DFSS (Design for Six Sigma) methodology to optimizing both the linearity and the sensitivity of the output voltage of a Hall-effect rotary position sensor. To this end, the dimensions and relative positions of a permanent magnet with reference to a Hall sensor are selected as the design factors for a full factorial design. In order to evaluate the output voltage of the rotary position sensor at each run in the experimental design, analytical solutions to the magnetic flux density were obtained using the Biot-Savart law and the relations between the magnetic flux density and the output voltage intrinsic to a Hall sensor. Through measurements of the improved output voltage of the rotary position sensors manufactured using the optimized design factors, the proposed method is shown to be simple and practical.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.4
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• pp.185-194
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• 2022

The software industry makes it possible to converge science and Information and Communication Technologies (ICT), create new markets, and create jobs. It is a key industry in the 21^st century knowledge and information age, which is growing very rapidly. This study uses Input-output analysis to derive Linkage effect of the software industry in Korea and the United States (US), and compares the result with CO₂ inducement effect to verify whether the industry meets the low carbon emission development strategy. As the result of this study, first, the software industries in Korea and the US are confirmed to have large influences on the national economy. Second, the Korean software industry has a low Forward linkage effect, so it is less affected by the output of other industries. On the other hand, in the US, it has a high Forward linkage effect and can induce a lot of output in others. Third, CO₂ inducement effects of the industry in Korea and the US are both low, confirming that the industry is suitable for a sustainable future.

• Smart Structures and Systems
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• v.12 no.6
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• pp.619-640
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• 2013

It is highly desirable to explore efficient algorithms for detecting structural damage of large size structural systems with limited input and output measurements. In this paper, a new structural damage detection algorithm based on substructure approach is proposed for large size structural systems with limited input and output measurements. Inter-connection effect between adjacent substructures is treated as 'additional unknown inputs' to substructures. Extended state vector of each substructure and its unknown excitations are estimated by sequential extended Kalman estimator and least-squares estimation, respectively. It is shown that the 'additional unknown inputs' can be estimated by the algorithm without the measurements on the substructure interface DOFs, which is superior to previous substructural identification approaches. Also, structural parameters and unknown excitation are estimated in a sequential manner, which simplifies the identification problem compared with other existing work. Structural damage can be detected from the degradation of the identified substructural element stiffness values. The performances of the proposed algorithm are demonstrated by several numerical examples and a lab experiment. Measurement noise effect is considered. Both the simulation results and experimental data validate that the proposed algorithm is viable for structural damage detection of large size structural systems with limited input and output measurements.

• Spatial Information Research
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• v.20 no.6
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• pp.69-76
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• 2012

In this study, we derived the characteristics of the geo-spatial information industry by using input-output analysis. For this analysis, we classified the geo-spatial information industry and reorganized the input-output table. And we derived the production inducement coefficient, index of the power of dispersion and index of the sensitivity of dispersion in the geo-spatial information industry. We confirmed that geo-spatial information industry has a small production inducement coefficient and a great forward linkage effect. Based on these facts, we suggested the strategy direction as follows: 1) building the industrial eco-system, 2) managing both advance and applicability enhancement, 3) Establishing from a long-term point of view.

• Macromolecular Research
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• v.14 no.6
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• pp.624-629
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• 2006

The cellulose-based, Electroactive Paper (EAPap) has recently been reported as a smart material with the advantages of lightweight, dry condition, biodegradability, sustainability, large displacement output and low actuation voltage. However, it requires high humidity.. This paper introduces an EAPap made with a cellulose solution and lithium chloride (LiCl), which can be actuated in room humidity condition. The fabrication process, performance test and effect of LiCl content of the EAPap actuator are illustrated. The bending displacement of the EAPap actuators was evaluated with actuation voltage, frequency, humidity and LiCl content changes. At a LiCl/ cellulose content of 3:10, the displacement output was maximized at a room humidity condition. Even though the displacement output was less than that of a high humidity EAPap actuator, the mechanical power output was not reduced due to the increased resonance frequency, which is promising for developing EAPap actuators that are less sensitive to humidity.

• Environmental and Resource Economics Review
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• v.16 no.2
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• pp.313-336
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• 2007

The paper is concerned with, firstly, estimating the North Korean input-output table in which energy sectors like electricity and petro products are specified and, secondly, computing the effect of an investment in the energy sector on North Korean economy, by using the estimated input-output table and applying CGE analysis. The 4,000 million dollar investment on North Korean electricity industry produces 368 million dollar worth of output and 156 million dollar worth of value added. The 150 million dollar investment on petro industry creates about 20.5 million dollar worth of output and 9.65 million dollar worth of value added in North Korea.

• The Journal of Fisheries Business Administration
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• v.43 no.3
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• pp.75-87
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• 2012

Today, the Korean fisheries is undergoing significant hardships, both domestically and internationally. While declining amount of catch, ascending international oil prices and others pose a compelling challenge to the fishing sector, the ever strengthening influence of international institutions related to fisheries and international trade organizations also compel to bring about myriad of changes in the realm of fishery products. Against the backdrop, this study attempted to examine the fisheries catch, aquaculture, service, processing fields in terms of its rippling effect and of how the industry has been changed by analyzing the past and present through an input-output analysis. As for research methods, 168 items of the input-output tables in 2000, 2005, 2009, and 2010 were integrated to form and classify 32 sectors (28 basic sectors + catch, aquaculture, fishery service, processed fishery products) so as to generate production inducement coefficient, sensitivity coefficient, and impact coefficient. The analysis results revealed that : though the linkage effect of fishery industry was not very sizable, the impact coefficient of the processed fishery products was high; the consumption and investment coefficient sector among production inducement coefficient was on an upturn trend ; the export coefficient was tended to decline. In the future research, it is necessary to carry out a study based on the integration of detailed classification (404 sector) and a study and analysis of fishery industry by different regions through the inter-regional input-output tables. The fishery industry is one of the crucial industries in Korea. The fishery industry is not only important in its own right but also significant as it exerts influence over other industries. Therefore, it is required that there should be more investment and supports for the development of the fishery industry, and pay efforts to ensure that the investment and development could lead to mutual growth for both the fishery and other various industries.