• 대한인간공학회지
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• 제26권2호
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• pp.15-20
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• 2007

The purpose of this study is to compare assessment techniques for Korean characters entry methods of mobile phones. This study was performed based on survey of relevant existing studies. The assessment techniques were classified into three: 1) predicting entry time using conceptual models such as Fitts' law, Hick-Hyman's law and KLM-GOMS model (conceptual model); 2) counting the number of pressing button(number of pressing button); and 3) measuring performance or rating subjective measures using real mobile phones(real mobile phone). The comparison revealed that the assessment results were different depending upon the techniques used. The results from the conceptual model using only Fitts' law and the number of pressing button were opposite to those from techniques of the real mobile phone and conceptual model using Fitts' and Hick-Hyman's laws. Based on this result and suggestions provided by the literature, it is recommended that for more precisely assessing interfaces of mobile phones such as Korean characters entry method, real mobile phones be used instead of the conceptual models.

• 대한조선학회논문집
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• 제36권4호
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• pp.37-47
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• 1999

본 논문에서는 접수(water entry) 및 이수(water exit) 문제를 유동장의 지배방정식인 2차원 비압축성 Navier-Stokes방정식을 일반좌표계(generalized coordinate system)에서 유한체적법(Finite Volume Method)으로 이산화 하여 해석하였다. 강체의 접수 또는 이수 상황에서 발생하는 자유수면 변형에 대한 처리는 Level-Set[11]기법을 사용하였다. 수치계산결과에서 접수에 대한 유체충격력에 대한 계산결과는 쐐기(wedge)형과 flared-ship 단면의 실험결과[5]와 비교하였으며, 원형실린더의 이수문제에서는 시간에 따른 자유수면의 변형 및 유동장의 특징을 살펴보았다.

• Journal of Yeungnam Medical Science
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• 제39권4호
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• pp.344-346
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• 2022

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly spread worldwide, leading the World Health Organization to declare coronavirus disease 2019 (COVID-19) a pandemic. To curb the unchecked spread of SARS-CoV-2 infection, most countries have enforced travel restrictions. However, it is debatable whether such restrictions are effective in containing infections and preventing pandemics. Rather, they may negatively impact economies and diplomatic relationships. Each government should conduct an extensive and appropriate analysis of its national economy, diplomatic status, and COVID-19 preparedness to decide whether it is best to restrict entering travelers. Even if travelers from other countries are allowed entry, extensive contact tracing is required to prevent the spread of COVID-19. In addition, governments can implement "travel bubbles," which allow the quarantine-free flow of people among countries with relatively low levels of community transmission. An accurate evaluation of the benefits and losses due to entry restrictions during the COVID-19 pandemic would be helpful in determining whether entry restrictions are an effective measure to reduce the spread of infection in future pandemics.

• International Journal of Aeronautical and Space Sciences
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• 제14권2호
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• pp.105-111
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• 2013

Radiative heating phenomena occurring in planetary entry flights are reviewed for the purpose of educating those who are not familiar with the problem. How the radiative heat transfer rates to the Apollo entry vehicle were measured and analyzed are first described. Next, the effects of thermo-chemical non-equilibrium on radiation are summarized. Then the radiation problems in entry flights into other planets are reviewed. Finally, unsolved problems are enumerated.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 Proceedings of the Korea Automatic Control Conference, 11th (KACC); Pohang, Korea; 24-26 Oct. 1996
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• pp.307-310
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• 1996

In this paper, we deal with some numerical analyses of a re-entry vehicle in a 2-dimensional plane as an optimal control problem. To reduce the dynamic load, the heat load and the oscillation in the trajectory, we researched the trajectories in which the load factor or the rate of flight path angle was minimized during re-entry. In addition to that, taking advantage of the monotonous subarc method and the folded time-axis method, we tried to find the heat-less and load-less trajectory with combinations of some sectional functionals so that we can achieve more comfortability.

• 유통과학연구
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• 제12권7호
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• pp.45-51
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• 2014

Purpose - This study aims to explore the success of Lotte Mart in the global market, as well as examining the factors related to its entry methods. Research design, data, and methodology - This study analyzed the differences between Lotte Mart and E-mart in terms of their market entry methods, based on references and secondary data. This study is based on qualitative research that analyzes actual cases. Based on the results, this study analyzed and discussed actual cases based on references and secondary data, including newspaper interviews on Lotte Mart. Results - Lotte Mart succeeded in adapting to local markets it did this by ensuring the use of both mergers and acquisitions (M&As) and greenfield methods. In contrast, E-mart utilized only greenfield methods. Conclusions - The findings of this study may not be generalized to all industries, as only Lotte Mart was examined using the case analysis method. Therefore, the successful market entry modes of various companies should be explored in terms of FDI.

• 품질경영학회지
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• 제29권3호
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• pp.18-38
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• 2001

This paper attempts to identify variables which affect Korean electronic commerce(EC) venture's strategies for the international market entry decision making. Especially in the perspective of quality management perspective, it is highly relevant question which factors are critical when the industry has high technology driven characteristics such as EC, product quality related factors or environmental factors. Technology competence, operational competence, local marketing competence, psychological barriers, domestic competition level, and local infrastructure level are included to generate the explaining model for international market entry decision. The result is that the higher technology competence and local marketing competence are the significant factors. The higher the perception in these factors, the higher the intention to enter the international market in EC industry. These factors play a pivotal role in determining to go abroad the foreign EC market. Our finding implies that the subjective confidence on quality of EC solution(technology competence) and venture's capability of maintaining it(local marketing competence) are the important factors, when EC ventures make the decisions to enter the foreign markets.

• 한국자동차공학회논문집
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• 제5권5호
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• pp.188-196
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• 1997

Many researchers have developed the measurement technique of in-cylinder flow characteristics and found the effect of intake port geometries on engine performance. The flow characteristics of four-valve cylinder head were examined in a steady flow rig for different intake ports. Tumble intensity of intake configurations with different entry angles were quantified with a tumble meter. The velocity and angular momentum distributions in the tumble adaptor were measured under steady conditions with PIV(Particle Image Velocimetry). We have obtained the results that flow structure becomes complicated by valve interference at low valve lift. As the valve interferences were reducing and the flow pattern changed to large vortex structure with tumble direction, intake ports with different entry angles have different tumble centers. Tumble eccentricity of intake port with low entry angle was large, so that the port had relatively much angular momentum compared to others which was expected to improve combustion performance.

• Journal of Mechanical Science and Technology
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• 제18권9호
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• pp.1519-1528
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• 2004

Atmospheric Re-Entry guidance is divided as longitudinal and lateral. This paper proposes a longitudinal reference trajectory and control law using the inverse dynamics method with pseudospectral Legendre method. Application of this method into Re-Entry problem forces a power of calculation time-reduction due to unnecessary of integration or any iteration as well as sufficient accuracy convergence. The used guidance scheme is time-to-go.

• 한국경영과학회지
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• 제31권4호
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• pp.105-123
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• 2006

Previous research on two-sided markets has, for the most part, concentrated on indirect network externalities between buyers alto sellers. This paper considers direct competition effect among sellers and among buyers as well as indirect network externalities. We develop an analytic model of C2C e-marketplaces and examine whether a monopolistic incumbent could successfully deter new entry into its market. We find that the effect of the number of sellers or buyers on the price of goods depends on whether sellers have decided to sell the goods using an auction or fixed pricing rule and on the characteristics of the goods. We argue that when the effect of the number of sellers on the price of goods is significantly larger than that of buyers, there is a high possibility of entry. In particular, we show that entry becomes more difficult to deter as fixed-price format is adopted more frequently or the proportion of collectables is relatively low.