• Journal of Ship and Ocean Technology
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• 제5권2호
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• pp.27-48
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• 2001

Turbulent flow calculations are performed for the two modern practical VLCCs with the sable forebody and the slightly different afterbody, i.e. KVLCC and KVLCC2. Three $\textsc{k}-\varepsilon$ turbulence models are tested to investigate the differences caused by the turbulence models. The calculated results around the two VLCC hull forms using O-O grid topology and profile-fitted surface meshes are compared to the measured data from towing tank experiment. The realizable $\textsc{k}-\varepsilon$model provided realistic wake distribution with hook-like shape, while the standard and RNG-based $\textsc{k}-\varepsilon$models failed. It is very encouraging to see that the CFD with relatively simple turbulence closure can tell the difference quantitatively as well as qualitatively for the two hull forms with stern frameline modification.

• 한국의류산업학회지
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• 제6권5호
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• pp.575-584
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• 2004

The purpose of this study was to investigate the differences in recognition of brand and advertisement image according to the advertisement expression forms of domestic make-up cosmetics. This study was conducted by means of a questionnaire survey of female which age from twenties to the thirties. The statistics used for data analysis were frequency distribution, Percentage, mean, factor analysis, and paired t-test by the SPSS program. The results of this study were as follows. The brand and advertisement image of domestic Make-up cosmetics were classified into seven factors. : Of good quality, high-toned, modern, chic, unique, familiar, stimulative brand and advertisement image. The brand image and advertisement image recognition didn't correspond in general except HERCYNA and ETUDE.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권9호
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• pp.4379-4397
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• 2017

Three different improvements of the Velocity-based model were proposed in a minimal velocity-based pedestrian model. The improvements of the models are based on the different agent forms. The different representations of the agent lead to different results, in this paper, we simulated the pedestrian movements in some typical scenes by using different agent forms, and the agent forms included the circles with different radiuses, the ellipse and the multi-circle stand for one pedestrian. We have proposed a novel model of pedestrian dynamics to optimize the simulation. Our model specifies the pedestrian behavior using a dynamic ellipse, which is parameterized by their velocity and can improve the simulaton accuracy. We found a representation of the pedestrian much closer to the reality. The phenomena of the self-organization can be observable in the improved models.

• 대한산업공학회지
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• 제37권4호
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• pp.279-288
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• 2011

The past researches focused on the supply chain network that consists of factories, distribution centers and retailers for single product type. This research is required because the factory for single product type is advanced to reconfigurable type in order to produce various products, according to customers' various purchase forms and time. This research is also required because in the past researches, the material flows from factories to distribution centers and from distribution centers to retailers, but recently, there are material flows between distribution centers. The supply chain network in this research consists of reconfigurable manufacturing system, multi-layered distribution centers, and retailers. A simulator is developed to analyze the material flow on the supply chain network. The developed simulator is web-based designed by using Java Server Page and MS-SQL, so as to maximize the convenience for users.

• International Journal of Reliability and Applications
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• 제18권2호
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• pp.65-82
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• 2017

Abstract. Camilo Dagum proposed several variants of a new model for the size distribution of personal income in a series of papers in the 1970s. He traced the genesis of the Dagum distributions in applied economics and points out parallel developments in several branches of the applied statistics literature. The main aim of this paper is to define a bivariate Dagum distribution so that the marginals have Dagum distributions. It is observed that the joint probability density function and the joint cumulative distribution function can be expressed in closed forms. Several properties of this distribution such as marginals, conditional distributions and product moments have been discussed. The maximum likelihood estimates for the unknown parameters of this distribution and their approximate variance-covariance matrix have been obtained. Some simulations have been performed to see the performances of the MLEs. One data analysis has been performed for illustrative purpose.

• 응용통계연구
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• 제22권1호
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• pp.205-220
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• 2009

For modeling skewed semicircular data, we derive new family of the exponential distributions. We extend it to the l-axial exponential distribution by a transformation for modeling any arc of arbitrary length. It is straightforward to generate samples from the f-axial exponential distribution. Asymptotic result reveals two things. The first is that linear exponential distribution can be used to approximate the l-axial exponential distribution. The second is that the l-axial exponential distribution has the asymptotic memoryless property though it doesn't have strict memoryless property. Some trigonometric moments are also derived in closed forms. Maximum likelihood estimation is adopted to estimate model parameters. Some hypotheses tests and confidence intervals are also developed. The Kolmogorov-Smirnov test is adopted for goodness of fit test of the l-axial exponential distribution. We finally obtain a bivariate version of two kinds of the l-axial exponential distributions.

• 한국군사과학기술학회지
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• 제13권6호
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• pp.1043-1050
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• 2010

This paper examined the probabilistic load analysis for the tailplane during pitching maneuvering in the conceptual aircraft design phase. The flight load analysis based on the probabilistic distribution of design variables are compared with the results of the deterministic analysis. Two forms of variable distribution are used in this paper. One is standard normal distribution, the other distribution is calculated from the results of short-period longitudinal equation of aircraft motion. The influence of the distribution parameter on the probabilistic load analysis was investigated and the significant design variables that have an impact on the mean and variance of probabilistic load were identified. The comparison indicates that probabilistic load analysis provides more reliable probabilistic load distribution for the structural design than the traditional deterministic analysis.

• The Journal of Asian Finance, Economics and Business
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• 제5권3호
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• pp.157-167
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• 2018

This research aims to generalize the conceptual basis of precariousness of employment, study the factors and scale of unsustainable of employment in the countries of the Eurasian Economic Union (EAEU). The concept of precariousness of employment is formed in social and economic studies about 40 years ago, but objective and subjective conditions and forms of unsustainable employment existed before. This study proposes a classification of forms of precariousness of employment on 16 criteria: the duration and timing of agreements, contract terms, the nature of income; the degree of labor autonomy; the level of formality; the level of openness; the level of vulnerability; the conditions of growth of qualification; the level of flexibility; the level of stability; regularity; the severity of the danger of work; in relation to the workplace; the quality of employment, the level of social security. In this research highlighted factors (globalization, demography, migration, structure factors, shadow and informal economy, social development and living standards, unemployment), and systematized certain trends of precariousness of employment, channels and means, forms of manifestation. The empirical analysis identified of the labor potential of the Eurasian countries and new quantitative estimates of the levels of unsustainable employment in the Eurasian Economic Space.

• 자원환경지질
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• 제57권2호
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• pp.219-231
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• 2024

인천광역시와 경기도에 소재한 레미콘 사업장을 대상으로 한 설문조사 결과를 기반으로 골재 운반거리 및 생산형태 분석을 수행하였으며, 골재 유통 특성과 현황을 해석하였다. 그 결과 수요지 도달거리가 20km 이내인 인천, 시흥, 부천, 김포, 시흥 지역은 생산과 타지역간 거래가 많은 양방향 유통형태를 가지며 20~50km인 파주, 용인, 양주, 포천 지역은 인천으로만 골재를 공급하는 단방향 유통형태를 나타내었다. 그리고 생산형태별 유통량 조사결과 인천지역에서 유통되는 자갈의 85% 이상이 건설현장에서 배출되는 암석으로 만든 부순골재로 공급망이 많이 편중된 것으로 나타났다. 이러한 결과들은 장기적으로 골재공급에 부정적인 영향을 줄 것으로 예상되며 적절한 골재 유통시장 형성을 위한 정책적 해결방안이 필요하다.

• 한국토양비료학회지
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• 제24권3호
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• pp.183-191
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• 1991

본 연구는 아연광산(亞鉛鑛山) 주변의 논토양에 존재하는 Cd, Pb, Cu 및 Zn의 형태별 함량을 조사하여 중금속간의 분포(分布) 특성(特性)을 검토하였으며, 토양 화학적 성질이 이들의 형태별 함량 분포에 미치는 영향을 밝히기 위하여 수행되었다. 그 결과를 요약하면 다음과 같다. 1. 공시토양에 존재하는 Cd, Pb, Cu 및 Zn은 주로 해화물-잔류태(殘留態)로 존재하였으며, Cd와 Pb의 산화물(酸化物)-탄산염태(炭酸鹽態)와 Cu의 유기복합태(有機複合態)의 함량도 높은 편이었다. Pb와 Cu의 치환태는 소량 존재하였으며, 수용태는 Zn만 검출되었다. 2. 치환태의 분포비가 높은 토양일수록 산화물-탄산염태 및 황화물-잔류태의 분포비가 낮았다. 3. 토심이 깊어질수록 치환태 Cd 및 Zn의 분포비(分布比)는 낮아지고 항화물-잔류태의 분포비가 높아졌으며, Pb는 산화물-탄산염태의 분포비가 낮아지고 황화물-잔류태의 분포비가 높아졌다. 4. Cu는 유기물이 많은 토양일수록 Cu의 유기복합태 함량이 많았으며, Cd, Pb 및 Zn의 유기복합태는 유기물함량과 관계가 없었다. 치환태 Cd, Pb 및 Zn의 분포비는 pH가 높은 토양일수록 낮았으나, 이들의 산화물-탄산염태과 황화물-잔류태의 분포비의 합은 높았다. Pb의 산화물-탄산염태 및 황화물-잔류태의 분포비는 공시토양의 pH 전범위에서 Cd 및 Zn에 비하여 높았다.