• Proceedings of the KSR Conference
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• 2000.11a
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• pp.93-100
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• 2000

This paper studied technical investigation of effective operation and methodology for technical combination in south and north korea. For harmonious transportation on railroad system, the system of trans-korea railroad investigated on each part(system, Rolling stock, Cartenary ＆ Electricity, Signal and Track etc). Though it isn't show many difference on railroad system, we can show some difference on rolling stock, track and signaling system. For the effective and competitive operation on south and north korea, Many problem investigated and proposed alternative proposal for selecting of rolling stock(diesel or electric), track and signaling improving for speed-up and compatible system at AC and DC system.

• CDE review
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• v.4 no.2
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• pp.30-35
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• 1998

Recently, many enterprises wish to preoccupy competitive positions in the market by motivating themselves towards CALS(Commerce At Light Speed) and try hard to achieve system implementation with the use of new concept-based backbone systems such as ERP(Enterprise Resource Planning) or PDM(Product Data Management). However, unfortunately there is an inevitable discrepancy during implementation period between package vendors and customers due to lack of clear methodology and misunderstanding about system. In some cases, consensus on partially verified system design invokes customers'continuous change demands and often it tends to result in unnecessary project delays. PDM application system implementation project of the company L has been studied here to solve these sorts of problems. The major yields of this work are achievement of a willing approval from customers and rapid system design under a time-limited and conceptually defined project scope and finally, through fully verified system design, we were able to reach successful system implementation.

• Korean Management Science Review
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• v.26 no.3
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• pp.67-78
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• 2009

In this paper, I analyze the mobile broadband services market characterized by vertical and horizontal differentiation. Vertical differentiation as service quality differentiation is based on the transmission speed of mobile internet service and horizontal differentiation as spatial differentiation is based on the service coverage. Theoretical explanations for the competitive price policy have been developed in the game context of WiBro which represent the high quality within the limited service coverage and HSDPA which represent relatively low quality with nation-wide service. When the WiBro has a mobile broadband service quality advantage and the difference in quality is sufficiently low, the price of WiBro with limited service coverage is relatively lower than that of HSDPA. This occurs because the advantage of WiBro's vertical service differentiation is offset by the disadvantage of horizontal differentiation. The difference in the quality of mobile internet service, however, is not too high, the price of WiBro is relatively higher than that of HSDPA. Moreover, when the service quality of WiBro is sufficiently high, the low quality HSDPA service faces no demand.

• Asia pacific journal of information systems
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• v.11 no.3
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• pp.63-89
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• 2001

The purpose of this research is to develop strategic alternatives for the high-tech products development by comparatively studying characteristics of the industry and R&D structures in Korea and the US. Some of the environmental, strategic, organizational and project teams' characteristics are studied. Data were collected from Korea and US high-tech companies through interviews and questionnaires and event analysis method was used to analyze them. The findings are as follows: First, when the level of market concentration is high, cycle time tends to be longer. Therefore, if there are many competitors in the market, new products development should be swift due to competitive pressures. Second, the developmental strategy should be directed toward the existing customers to speed up new products development. That is, a defensive strategy would result in a shorter cycle time and response time compared to a strategy directed to a niche market. Third, when the level of formalization is high, cycle time tends to be shorter. This means that formal procedures for new products idea development or new products development policies shorten new products development time.

• Journal of Internet Computing and Services
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• v.20 no.3
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• pp.25-31
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• 2019

Along with the recent advances in quantum computers, it is anticipated that cryptographic attacks using them will make it insecure to use existing public key algorithms such as RSA and ECC. Currently, a lot of researches are underway to replace them by devising PQC (Post Quantum Cryptography) schemes. In this paper, we propose a performance enhancement method for Lizard implementation which is one of NIST PQC standardization submission. The proposed method is able to improve the performance by 7 ~ 25% for its algorithms compared to the implementation in the submission through the techniques of various implementation aspects. This study hopes that Lizard will become more competitive as a candidate for PQC standardization.

• Korean Journal of Poultry Science
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• v.18 no.1
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• pp.57-66
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• 1991

The broiler industry in Korea has been gradually changing its structure of independent operation into integrated and coordinated production and marketing system. It was in 1960s when the broiler industry first tried the integrated effort, but never succeeded as it was expected since due mainly to growers' attitudes favorable for traditional operation and agribusiness' passive response on structure change. Until mid 1980s, however, a bit of partially integrated system had been evolved by several factor suppliers. Recent years have furthered its progress toward completely integrated pattern, the ultimate goal of broiler integration. It is true that the external factors including the GATT Negotiations through the Uruguay Round stimulated the people involved in the industry to find the way of making it competitive to survive in the open, liberalized world economic system rapidly emerging through the process of globalization. Once the industry realized the necessity of reducing the cost of production and improving the quality of it, the conclusion tended to come to the point of an entire structural alteration by means of integration rather than an improvement of a certain segment such as marketing. It is very obvious. therefore. that the movement toward the complete integration will speed up in a coming few years under the leadership of not only entrepreneurs but also producers group. According to a report. there were three almost complete integrators and thirteen partial integrators as of December, 1990, all of which eagerly directed toward the completely integrated system in due course . Among others as an advantage of integrated structure. the cost saving must be pointed out as the greatest one In a survey, it was estimated that the cost of dressed and ready-to-eat chicken could be lowered by 31.8 percent and 41.5 percent, respectively, over that to be under the independent, non-integrated system. As long as everybody concerned about the future of the industry in the open market mechanism realizes the importance of the structure change through an integration, the broiler sector of Korean agriculture shall be moving toward the direction of vertically and completely integrated structure in order to make it competitive, even to export, hopefully before 1995 or by the end of this century in any case.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1681-1698
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• 2011

According to the demands of the times, Inchon international airport railroad opened up step by step but It is situation that much government subsidies are paid because It does not competitive power with road traffic by decline of schedule speed. Inchon international airport railroad users will convert by other transportation and minimize damage their time as travel time is prolonged. Therefore, need high speedization of airport railroad, this may act big role competitive power security as well as airport railroad activation with another public transportation. Thus, this paper suggests that a high speedization possibility section in the sections of airport railroad and train speed elevation effect analysis by roadbed, railroad, system improvement and the most efficient operation intervals analyzing each vehicles (AREX (120km/h), KTX (230km/h), EMU(Electric Multiple Unit, 180km/h) train running pattern.

• Journal of Wetlands Research
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• v.22 no.2
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• pp.113-120
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• 2020

For the conservation of both Sericinus montela (vulnerable species by red book of Korea) and A. contorta, we investigated environmental factors affecting the growth and reproduction of Aristolochia contorta. We selected four A. contorta habitats at Gapyeong, Pyeongtaek, Cheongju, and Yeoju in Korea and surveyed community and habitat characteristics of companion species, herbivore appearance, support types, and soil physicochemical properties in July and October, 2018. Habitat environments and the growth and reproduction characteristics of A. contorta were different according to four habitats of different regions. In particular, the fastest growth speed and earliest flowering and fruiting were observed in Pyeongtaek. Growth of A. contorta in Cheongju and Yeoju were interrupted by aboveground damage from human disturbance. In this study, support types seemed to be important for growth speed of A. contorta. Flowering and fruiting timing were likely to be related to combined effects of soil cation contents and competitive and herbivore stresses. Therefore, providing effective support and reducing biological stress should be necessary for stable growth and proper flowering and fruiting timing of A. contorta. In addition, experimental evidence would be needed to figure out the effect of soil cation and biological stress on flowering and fruiting of A. contorta in detail.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.5
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• pp.337-343
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• 2020

This study proposed piezoelectric ceramic bender actuators for application to small walking robots. As the space where human access has recently become increasingly restricted (e.g., highly concentrated radioactive storage areas, viral contaminated areas, terrorist zones, etc.), the scope of using robots is becoming more diverse, and many actions that were possible only in the past have been attempted to be replaced by small robots. This robotic concept has the advantage of being simple in structure, making it compact and producing a large size work force. The dynamic modeling, using finite element analysis, maximized the robot's mobility performance by optimizing the shape of the actuator, and the results were verified through fabrication and experimentation. The actuator moved at a maximum speed of 236 mm/s under no load conditions, and it could move at a speed of 156 mm/s under load conditions of 5g. The proposed actuator has the advantage of modular additions depending on the mission and required performance, which ensured that they are competitive against similar drive sources previously created.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.8
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• pp.911-916
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• 2014

The leisure boat industry has the potential to become a high-value-added industry in the future. Recently, a study on Korean high-speed leisure boats for fishing was conducted. This study suggests a product configuration model-based shipbuilding cost estimation method for determining the type of leisure boat suitable for mass production, as part of a research for productivity improvement. The suggested estimation method based on the analysis of the leisure boat process and generic YWBS can calculate quantitative and concrete data. By using this method, the cost of building the catamaran-type design ship can be reduced by 17 times, compared to that of the monohull-type mother ship. This implies that the final design of the Korean high-speed leisure boat for fishing will have a competitive price at the actual production stage.