• Title/Summary/Keyword: wake model

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Interest in Smoking Cessation and Its Related Factors in Male Smokers (남성 흡연자의 금연에 대한 관심도 및 관련 요인)

  • Shin, Taek-Soo;Lim, Young-A;Cho, Young-Chae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.4
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    • pp.362-373
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    • 2018
  • This study was conducted to investigate the relationship between interest in smoking cessation and factors that define this interest. The study subjects were 593 male civil servants who work at D metropolitan city and were smokers at the time of the survey. The research method was a survey using a self-administered questionnaire in October 2015. Interest in smoking cessation of study subjects showed that 28.3% had no interest in smoking cessation, 45.7% were interested in smoking cessation, but had no intention to quit within six months, and 26.0% were interested in smoking cessation and intended to quit within six months. Multiple regression analysis revealed that the factors influencing interest in smoking cessation with explanatory powers of 23.6% were employment type, age when first starting smoking, number of cigarettes smoked per day, time from when you wake up until you smoke your first cigarette, recognition of susceptibility to lung cancer, and benefits to smoking cessation. Logistic regression analysis revealed that the odds ratio of recognition of susceptibility for lung cancer, benefits to smoking cessation, and barriers to smoking cessation were significantly increased in the group with interest in smoking cessation and intention to quit within six months vs. the group with no interest in smoking cessation. Taken together, these results suggest that cancer prevention due to smoking and awareness of the seriousness of health problems caused by smoking were factors increasing interest in smoking cessation.

Constructivist Implications of the 9.19 Military Implementation Agreement (9.19 군사합의서의 구성주의적 함의 고찰)

  • Lee, Kang Kyong;Seol, Hyeon Ju
    • Convergence Security Journal
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    • v.20 no.2
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    • pp.101-110
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    • 2020
  • Since the third inter-Korean summit, the inter-Korean summit in Pyongyang and the U.S.-North Korea summit in Singapore and Hanoi, denuclearization negotiations are under way that will determine the fate of the Korean Peninsula. However, the negotiations are stalled and some skepticism is expected due to the conflicting U.S.-North Korea stance over the terms of denuclearization. The reason why it is difficult to realize the complete denuclearization of North Korea is that there are a variety of variables such as the traditional security dilemma in Northeast Asia, the hegemonic competition between the U.S. and China, and the formation of a new cold-war system. At a turning point when three inter-Korean summits and three U.S.-North Korea summits were held in the wake of the 2018 PyeongChang Winter Olympics, North Korea's complete denuclearization has become a must-do historical task for Northeast Asia and world peace beyond the Korean Peninsula. In this sense, the inter-Korean summit in Pyongyang is seen as a historic occasion for presenting a new milestone for the denuclearization of North Korea and the development of inter-Korean relations through the 9.19 Pyongyang Joint Declaration and the Military Agreement. Meanwhile, Constructivism, which has become the main paradigm of international political theory, presents the view that ideological variables such as ideology, history and culture define material factors, identity and interests of state actors, and that the structure of international relations can be changed through interaction. In this study, the historical meaning of the 9.19 Pyongyang Declaration, which is now past its first anniversary, was considered from a constructivist perspective. To this end, the development process of constructivism theory and analysis model and the development process of inter-Korean relations were briefly reviewed, and the military implications of the 9.19 Military Agreement were presented.

A Propeller Design Method with a New Blade Section : Applied to Container Ships (새로운 날개단면을 이용한 프로펠러 설계법 - 콘테이너선에 응용 -)

  • J.T. Lee;M.C. Kim;J.W. Ahn;S.H. Van;H.C. Kim
    • Journal of the Society of Naval Architects of Korea
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    • v.28 no.2
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    • pp.40-51
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    • 1991
  • A Propeller design method using the newly developed blade section(KH18), which behaves better cavitation characteristics, is presented. Experimental results for two-dimensional foil sections show that the lift-drag curve and the cavitation-free bucket diagram of the new blade section are wider comparing to those of the existion NACA sections. This characteristic of the new section is particularly important for marine propeller applications since angle of attack variation of the propeller blade operating behind a non-uniform ship's wake is relatively large. A lifting surface theory is used for the design of a propeller with the developed section for a 2700 TEU container ship. Since the most suitable chordwise loading shape is not known a priori, chordwise loading shape is chosen as a design parameter. Five propellers with different chordwise loading shapes and different foil sections are designed and tested in the towing tank and cavitation tunnel at KRISO. It is observed by a series of extensive model tsets that the propeller(KP197) having the chordwise loading shape, which has less leading edge loading at the inner radii and more leading edge loading at the outer radii of 0.7 radius, has higher propulsive efficiency and better cavitation characteristics. The KP197 propeller shows 1% higher efficiency, 30% cavitation volume reduction and 9% reduction of fluctuating pressure level comparing to the propeller with an NACA section. More appreciable efficiency gain for the new blade section propeller would be expected by reduction of expanded blade area considering the better cavitation characteristics of the new blade section.

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The Review of KDAB Agriculture Project for the Rural Development in Bangladesh (방글라데쉬 농촌 개발을 위한 케이디에이비 농업 개발사업의 평가)

  • Kwon, Byung-Hee
    • Journal of Agricultural Extension & Community Development
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    • v.3 no.2
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    • pp.197-209
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    • 1996
  • Bangladesh that is known as the poorest country of the world has the large land of fertile soil and very good environment to live, even though we think she may be very bad to live. People being habituated to that good environment, the population explosion made the people to be starven, but the treatment has been simple support without deep analysis of the root of poverty. As the result it is general that the poverty is severer and severer in spite of continuous support. For the last century Korea changed from the country of poverty and despair to that of development and hope, to be model mid vision of under development countries including Bangladesh. At this point it is necessary to look back the way of development to help them to solve their poverty problem. That is the goal of this project, and this thesis is the result of it. It is evaluated for the 1st 5 years work of the project to apply the result to the next 5 years plan. This project had been proceeded from 1. Jul. 1990 to 30. Jun. 1995 at Chilmari area of Bangladesh, with teaching and training to wake up the mentality of the people, demonstration farming and cooperative association. It was proceeded as the Agriculture project of KDAB(Korean Development Association in Bangladesh, an NGO registered to Bangladesh) supported by Good Neighbors, KOICA and many churches and individuals. Especially the teaching and training work was proceeded as the branch of the Canaan Farmer`s School of Korea with instruction and support. After the basic survey for project, the confirmation of working place and the preparation of training facility, 10 times of long term training(3 months worse, boarding) was completed, with many times of short term training, informal training, demonstration farm, various demonstrating works. The results of the work are understanding of the not of problem by participatory observation, making plan to solve it, getting the trust from the people and beginning the practical work with the trainees for development of economy and living situation. The biggest problem of Bangladesh is being understood losing the desire to solve the poverty problem and the self-confidence to be able to do it. It is the conclusion that after solving the problem of thought and mentality, the education, technology and money can be effective for development. So the 1st 5 year project is evaluated as the basic work to analyse the root of problem, to chance mentality of people and to search income source. The next goal is to promote practical living level of people. For that it is necessary to develope die mentality of people including responsibility and self-confidence by teaching and training, to educate cooperative association and technology for economical development, to proceed integrated rural development work with economical development, educational improvement and reformation of environment. It is very important result that they decided to grow poultry for main economical source of Chilmari area, to do economical development work by joint operation of poultry through cooperative association.

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Wind Tunnel Test Study on the Characteristics of Wind-Induced Responses of Tall Buildings with Openings (중공부(中空部)를 가진 고층건축물(高層建築物)의 풍응답(風應答) 특성(特性)에 관한 풍동실험(風洞實驗) 연구(硏究))

  • Kim, Dong Woo;Kil, Yong Sik;Ha, Young Cheol
    • Journal of Korean Society of Steel Construction
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    • v.17 no.4 s.77
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    • pp.499-509
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    • 2005
  • The excessive wind-induced motion of tall buildings most frequently result from vortex-shedding-induced across-wind oscillations. This form of excitation is most pronounced for relatively flexible, lightweight, and lightly damped high-rise buildings with constant cross-sections. This paper discusses the aerodynamic means ofmitigating the across-wind vortex shedding induced in such situations. Openings are added in both the drag and lift directions in the buildings to provide pressure equalization. Theytend to reduce the effectiveness of across-wind forces by reducing their magnitudes and disrupting their spatial correlation. The effects of buildings with several geometries of openings on aerodynamic excitations and displacement responses have been studied for high-rise buildings with square cross-sections and an aspect ratio of 8:1 in a wind tunnel. High-frequency force balance testshave been carried out at the Kumoh National University of Technology using rigid models with 24 kinds of opening shapes. The measured model's aerodynamic excitations and displacement were compared withthose of a square cylinder with no openings to estimate the effectiveness of openings for wind-induced oscillations. From these results, theopening shape, size, and location of buildings to reduce wind-induced vortex shedding and responses were pointed out.

On The Development of The Stern Form with Low Resistance and High Propulsive Efficiency for Full Ships (저저항(低抵抗) 고추진(高推進) 효율(效率)의 비대선(肥大船) 선미선형(船尾船型)의 개발(開發)에 관하여)

  • Ho-Chung,Kim;Chun-Ju,Lee;Young-Bok,Choi
    • Bulletin of the Society of Naval Architects of Korea
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    • v.27 no.3
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    • pp.89-99
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    • 1990
  • It is required to develop a hull form with low resistance and high propulsive efficiency for the improvement of the ship-board operational economy. Since the hull forms with low resistance frequently have lower propulsive efficiency and on the other hand the hull forms with higher propulsive efficiency don't show good resistance characteristics, it is always very difficult to obtain economical hull forms which require less propulsive power accordingly. Efforts have been made to pursue a stern form with excellent resistance and propulsion characteristics together by shaping the run of the so-called buttock-flow type stern, which is known to have good viscous resistance performance, like that of conventional aftbody(U-type or Hogner type) featured by high propulsive efficiency. First model tests confirmed that the above concept can be one of the alternative approaches to the design of the good stern form and by the continuing efforts thereafter for the refining of the concept, propelled by the first promising results, stern form of good resistance performance together with good propulsive efficiency has been realized to some extent. In addition, it is confirmed that the new new stern can have better cavitation and vibration characteristics due to uniform wake-fields and the compact engine room arrangement can be possible due to it's larger floor area in way of engine room double bottom as compared with usual barge stern.

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An Analysis of Interaction between Exchange Rates and Stocks in Japan: Focusing on the Comparison between Periods of Financial Crisis and Non-financial Crisis (일본 외환시장과 주식시장 수익간의 관련성분석 : 금융위기와 비금융위기 시기 상호비교를 중심으로)

  • Lee, Keun-Jae;Cho, Nam-Hyung;Zhu, Shi-You;Yi, Seong-Baek
    • International Area Studies Review
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    • v.14 no.1
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    • pp.55-76
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    • 2010
  • This paper analyses interaction between yen/dollar exchange rates and NIKKEI index using bivariate GJR-GARCH(1,1) model. The data employed for the study is daily data series for the period of Jan. 4, 1995 through Aug. 30, 2009. One of main findings is that market inefficiency appears in the periods of financial crisis. Second, the volatility of exchange rates and stock returns has more increased in the wake of the volatility shock of the previous period during financial crisis than during non-financial crisis. Third, interestingly, the asymmetric volatility shock by bad news in those markets is bigger in financial crisis period than in non financial crisis. Fourth, in the period of current global financial crisis triggered by subprime mortgage crisis in U.S, volatility shock at the previous period is bigger than that of Asian financial crisis that happened in 1997. Lastly, the correlation between both returns of exchange rates and stock prices turns up positive according to the empirical estimation. This result may come from the fact that Japanese stock market does not have much attraction for international financial investment compared to stock markets of neighbouring countries like China, Korea and so on, while real sector's contribution to the economy is considered more importantly.

Impacts of Minijob on Women's Employment in Germany (독일 미니잡이 여성 고용에 미친 영향)

  • Kang, Su-Dol
    • Korean Journal of Labor Studies
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    • v.23 no.2
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    • pp.277-306
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    • 2017
  • This article empirically explores the impact of minijobs in the wake of the Hartz reform in Germany on women's employment relationship. Theoretically it is of great significance to examine whether the minijobs play an active role as a bridge in leading the minijobbers to regular, socially secured jobs or not. Several interviews as well as secondary data I could get during my sabbatical in 2015 were used to test the theory. One of the main findings was the fact that the minijob labor market opened doors wide for women in Germany, particularly for career-interrupted women, students or pensioners. However, the minijob can easily become a trap of lowest income and poverty for women. Most women minjobbers cannot go over to regular, socially secured jobs. Especially in terms of collective industrial relations, it considerably damages the power of industrial unions and the legal binding force of collective agreement. In conclusion, this study makes it clear that the labor market segmentation theory rather than the transitional labor market theory is valid in accounting for the reality of minijob in Germany. In other words, the minijob in Germany has a Toijan Horse Effect. It also suggests, from a practical viewpoint, that German industrial unions or works councils organize the minijobbers and that the coverage of collective agreements be extended to the minijobbers. Consequently, the time-selective part-timer model put into practice in Korea in 2014 is not only invalid but also undesirable.

Investigation on relative contribution of flow noise sources of ship propulsion system (선박 추진시스템 유동 소음원 상대적 기여도 분석)

  • Ha, Junbeom;Ku, Garam;Cheong, Cheolung;Seol, Hanshin;Jeong, Hongseok;Jung, Minseok
    • The Journal of the Acoustical Society of Korea
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    • v.41 no.3
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    • pp.268-277
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    • 2022
  • In this study, each component of flow noise source of underwater propeller installed to the scale model of the KVLCC2 is investigated and the effect of each noise source on underwater-radiated noise is quantitatively analyzed. The computation domain is set to be the same as the test section of the large cavitation tunnel in the Korea Research Institute of Ship and Ocean Engineering. First, for the high-resolution computation of flow field which is noise source region, the incompressible multiphase Delayed Detached Eddy Simulation is performed. Based on flow simulation results, the Ffowcs Williams and Hawkings integral equation is used to predict underwater-radiated noise and its validity is confirmed through the comparison with the tunnel experiment result. For the quantitative comparison on the contribution of each noise source, the spectral levels of sound pressure and power levels predicted using propeller tip-vortex cavitation, blade surface and rudder surface as the integral region of noise sources are investigated. It is confirmed that the cavitation which is monopole noise source significantly contributed to the underwater-radiated noise than propeller blades and rudder which is dipole noise source, and the rudder have more contribution than propeller blades due to the influence of the propeller wake.

Economic Effects of Eliminating Trade Barriers under Imperfect Competition (불완전경쟁하(不完全競爭下)에서의 무역장벽(貿易障壁) 완화효과(緩和效果))

  • Lee, Hong-gue
    • KDI Journal of Economic Policy
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    • v.14 no.2
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    • pp.29-54
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    • 1992
  • Recent studies on the economic effects of trade liberalization and economic integration have emphasized the significant gains associated with product differentiation and scale economies. Securing access to markets in other countries will make it possible to increase product variety and capture scale economies, thus, expanding the gains from trade. Liberalization is also expected to introduce foreign competition into the previously closed market. Concurrently, the liberalization will improve the competitive market environment for firms selling in the domestic market. Firms will be pressed to either exit or reduce cost. The output per firm, then, will increase due to the exit of rival firms, and the average total cost will decline due to the economies of scale. 'Rationalization' of the production process will eventually follow. This paper addresses the economic effects of (counterfactual) bilateral tariff elimination between Korea and Japan. It computationally assesses the gains from liberalization as well as the resource allocations and welfare effects associated with the tariff reduction. The endogenous determination of the key parameters distinguishes this paper from others. The firm's perceived elasticity of demand and elasticity of substitution in the present model are calibrated to be consistent with the base year data. Korea, Japan, and the rest of the world are modeled explicitly. The sectoral coverage of the model includes twenty-three tradable product categories based on three-digit SITC industries and seven nontradable categories based on one-digit SITC industries. Product categories are also classified into perfectly competitive and imperfectly competitive ones. In the imperfectly competitive industries, product differentiation exists at the firm level, while the perfectly competitive industries are characterized by national product differentiation. The simulation results of bilateral tariff reduction are reported. Tariff elimination tends to increase intra-industry trade flows so that the total amount of exports and imports of both countries expand. Yet, Japan is expected to increase the bilateral trade surplus in the wake of the mutual tariff reduction. Terms-of-trade for Korea will not change, while for Japan it will deteriorate. Equivalent variations reflecting the change in consumer surplus (welfare) will favor Korean consumers. Total output, however, will not change substantially, recording 0.5 and 0.6% for Japan and Korea, respectively. An interesting finding in the analysis is that the gains from increased competition and scale efficiency are not as prevailing as expected in theory.

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