• The Transactions of the Korean Institute of Electrical Engineers
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• v.34 no.9
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• pp.368-375
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• 1985

This paper describes the OPTIMAL PWM strategy to reduce harmonic losses for a variaboe-speed drive of an induction motor. This OPTIMAL theory is the strategy which can reduce motor losses by defining harmonic losses as a performance index and achieving it's minimization. This PWM strategy is compared with the conventional NATURAL PWM technique by a numerical method, and verified the validity of numerical method by a result of implementing in a practical 1 Hp-3 Phase induction motor drive system. Also, we could achieve a maximum efficiency to drive an induction motor by selecting appropriately one alternative between OPTIMAL and NATURAL PWM techniques, and employing it in a full driving range.

• Smart Structures and Systems
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• v.1 no.2
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• pp.121-140
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• 2005

This paper presents a systematic investigation of the effect of sensor location on the data quality and subsequently, on the effectiveness of machine health monitoring. Based on an analysis of the signal propagation process from the defect location to the sensor, numerical simulations using finite element modeling were conducted on a bearing test bed to determine the signal strength at several representative sensor locations. The results showed that placing sensors closely to the machine component being monitored is critical to achieving high signal-to-noise ratio, thus improving the data quality. Using millimeter-sized piezoceramic plates, the obtained results were evaluated experimentally. A comparison with a set of commercial vibration sensors verified the developed structural dynamics-based sensor placement strategy. It further demonstrated that the proposed shock wave-based sensing technique provided an effective alternative to vibration measurement, while requiring less space for sensor installation.

• Korean Management Science Review
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• v.28 no.1
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• pp.159-167
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• 2011

The theory of random utility maximization (RUM) defines the probability of an alternative being chosen as the probability of its utility being perceived as higher than those of all the other competing alternatives in the choice set (Marschak 1960). According to this theory, consumers perceive the utility of an alternative not as a constant but as a probability distribution. Over the last two decades, there have been an increasing number of studies on the effect of utility variance on choice probability. The common result of the previous studies is that as the utility variance increases, the effect of the mean value of the utility (the deterministic component of the utility) on choice probability is reduced. This study provides a theoretical investigation on the effect of utility variance on choice probability without any assumptions on the specific forms of probability distributions. This study suggests that without assumptions of the probability distribution functions, firms cannot apply the marketing strategy of maximizing choice probability (or market share), but can only adopt the strategy of maximizing the minimum or maximum value of the expected choice probability. This study applies the Chebyshef inequality and shows how the changes in utility variances affect the maximum of minimum of choice probabilities and provides managerial implications.

• International Commerce and Information Review
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• v.14 no.2
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• pp.81-119
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• 2012

In order to maintain high level of control over and close coordination of foreign marketing activities, export manufacturers often consider vertical integration strategy into global distribution. However, full integration is not always a feasible option. The purpose of this study is to investigate the alternative ways to achieve optimal level of control over export channel system for desirable channel performance. This study investigates different options for integration of the vertical channel structure, and examines their effect on the performance. The findings of this study suggest different combination of ownership and coordination level has varying impact upon channel performance: efficiency, effectiveness, and adaptiveness. This implies exporters may achieve desirable performance control over export channel without fully integrating the channel via ownership.

• East Asian Journal of Business Economics (EAJBE)
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• v.8 no.4
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• pp.29-43
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• 2020

Purpose - Although it has been 10 years since the university technology holding company was launched, it is currently facing operational limitations. The purpose of this study is to study the growth strategy of university technology holding companies by investigating the status and problems of university technology holding companies. Research design, data, and methodology - In this study, the status of university technology holding companies was analyzed based on the survey data issued by the University Technology Holding Companies Association. Due to the lack of research on university technology holding companies, policy alternatives were suggested by examining problems based on literature research. Result - In this study, an alternative to strengthening the competitiveness of technology holding companies and supporting policies was suggested. As a result of the research, it was discovered as a policy alternative to enhance the independence of technology-owned subsidiaries, develop outstanding talents, and expand the marketing of support programs to create results based on technology holding companies. Conclusion - In previous studies, alternatives to technology commercialization policies have been suggested, but studies on the role and status of detailed technology holding companies are insufficient, and the operation system of technology holding companies and discovery of future growth models are insufficient compared to overseas cases. Therefore, in this study, various policy innovation measures are presented as examples.

• Animal Bioscience
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• v.35 no.8
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• pp.1109-1120
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• 2022

Antibiotics used to be supplemented to animal feeds as growth promoter and as an effective strategy to reduce the burden of pathogenic bacteria present in the gastro-intestinal tract. However, in-feed antibiotics also kill bacteria that may be beneficial to the animal. Secondly, unrestricted use of antibiotics enhanced the antibiotic resistance in pathogenic bacteria. To overcome above problems, scientists are taking a great deal of measures to develop alternatives of antibiotics. There is convincing evidence that probiotics could replace in-feed antibiotics in poultry production. Because they have beneficial effects on growth performance, meat quality, bone health and eggshell quality in poultry. Better immune responses, healthier intestinal microflora and morphology which help the birds to resist against disease attack were also identified with the supplementation of probiotics. Probiotics establish cross-feeding between different bacterial strains of gut ecosystem and reduce the blood cholesterol level via bile salt hydrolase activity. The action mode of probiotics was also updated according to recently published literatures, i.e antimicrobial substances generation or toxin reduction. This comprehensive review of probiotics is aimed to highlight the beneficial effects of probiotics as a potential alternative strategy to replace the antibiotics in poultry.

• Journal of Information Technology Applications and Management
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• v.18 no.4
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• pp.81-93
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• 2011

By using GOSST theory, this paper models SSCFLP taking FLP, capacity of the facilities, single source capacitated limitation level and service enhancement issues into consideration. GOSST theory is strongly suggested as the solution procedure for these issues. We have used clustering of Center of Gravity method using the case study of the company S and then, took a heuristic GOSST measure in the alternative selection process. As a result, the research finds an alternative solution that both meets the satisfactory level of service and achieves consistent distribution capacity. When using this modeling, especially, to select the location of the logistics distribution center, the efficiency of current facilities is maximized while offering the minimum geometric distance for the alternative. Also, we can expect that the illustrated model and alternative solution can be applied to architecture of distribution system, to selection of telecommunication system locations for wireless network and to relocation of related facilities due to their sensitivities to location and weight.

• Journal of the Korean housing association
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• v.22 no.6
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• pp.1-10
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• 2011

In relation to the environmental analysis system of social marketing, this study has analyzed the responses made by the future users of the integrated apartments for the elderly that are currently under development as an alternative for the housing of the aging society. By studying the comprehensive social benefits, individual benefits and the implied factors for conceptual and behavioral changes in terms of the integrated apartments for the elderly, some important study results were obtained for the practical application of the new alternative. The major points are as follows: Firstly, from social aspect, the respondents wanted to know in detail about the integrated apartments for the elderly, the new alternative was evaluated to be helpful in elderly life, and it was expected to be effective for supporting the elderly people from psychological aspect. Secondly, from supply aspect, it was revealed that an alternative for the integrated apartment for the elderly is required to be developed in details reflecting the diverse needs of the elderly people and to be developed with differentiating strategy, but its applicability may confront some difficulties. Thirdly, from private aspect, the respondents showed they would feel economic burden if an integrated apartment for the elderly is introduced actually.

• Asian Journal of Atmospheric Environment
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• v.8 no.1
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• pp.59-68
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• 2014

The Fukushima nuclear accident in 2011 had an extensive impact on the national electricity plans. This paper outlines alternative electricity scenarios that meet the goals of nuclear phase-out and greenhouse gas (GHG) emission reduction. This paper also analyzes the results of each scenario in respect to the electricity mix, GHG emissions, costs and employment effects. The Long-range Energy Alternatives Planning system (LEAP) model was used to simulate the annual electricity demand and supply system from 2011 to 2030. The reference year was 2009. Scenarios are reference (where existing plans are continued), A1, A2, B1, B2, and C2 (where the levels of demand management and nuclear phase-out are different). The share of renewable energy in the electricity mix in 2030 for each scenario will be increased from about 1% in 2009 to 8% in the reference scenario and from 11% to 31% in five alternative scenarios. Total cumulative cost increases up to 14% more than the reference scenario by replacing nuclear power plants with renewable energy in alternative scenarios could be affordable. Deploying enough renewable energy to meet such targets requires a roadmap for electricity price realization, expansion of research, development and deployment for renewable energy technologies, establishment of an organization dedicated to renewable energy, and ambitious targets for renewable energy.

• Journal of the Economic Geographical Society of Korea
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• v.13 no.3
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• pp.498-513
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• 2010

This paper aims to critically discuss the place-marketing strategy that has been widely seen as an alternative way of regional development for the last decade in South Korea. In particular, it argues that the place-marketing strategy is highly likely to intensify the inter-local or inter-urban completion and to result in the territorialization of places because it is based on the essentialist notion of place that has been suggested by the humanistic geographers. In order to logically support my argument, I will critically review the essentialist notion of place, and introduce an alternative notion of place, in which the place is seen as socially constructed through complicated power relations and social, political and cultural processes. Also, I will logically demonstrate that the place-marketing can be seen as a strategy for territorializing places by discussing how territory is socially and politically constructed as a particular form of place.