• 수산경영론집
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• 제46권3호
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• pp.103-118
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• 2015

The purpose of this paper is to discuss possibilities of applying growth curve models, such as Logistic, Log-Logistic, Log-Normal, Gompertz and Weibull, to three specific technology areas of Fishery Science and Technology in the process of measuring their technology level between Korea and countries with the state-of-the art level. Technology areas of hazard control of organism, environment restoration, and fish cluster detect were selected for this study. Expert panel survey was conducted to construct relevant panel data for years of 2013, 2016, and a future time of approaching the theoretical maximum technology level. The size of data was 70, 70 and 40 respectively. First finding is that estimation of shape and location parameters of each model was statistically significant, and lack-of-fit test using estimated parameters was statistically rejected for each model, meaning all models were good enough to apply for measuring technology levels. Second, three models other than Pearl and Gompertz seemed very appropriate to apply despite the fact that previous case studies have used only Gompertz and Pearl. This study suggests that Weibull model would be a very valid candidate for the purpose. Third, fish cluster detect technology level is relatively higher for both Korea and a country with the state-of-the-art among three areas as of 2013. However, all three areas seem to be approaching their limits(highest technology level point) until 2020 for countries with the state-of-the-art. This implies that Korea might have to speed up her research activities in order to catch up them prior to 2020. Final suggestion is that future study may better apply various and more appropriate models respectively considering each technology characteristics and other factors.

• 사회복지연구
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• 제48권4호
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• pp.33-57
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• 2017

본 연구는 점증하는 가계부채에 대한 관심과 우려가 커지는 상황에서 가계부채가 부부폭력의 위험에 미치는 영향을 분석하였다. 자료는 한국복지패널 4~11차(2009~2016년) 데이터를 활용하였으며, 분석방법으로는 일반화추정방정식(Generalized Estimating Equations)을 사용하였다. 분석 결과, 가계부채비(가처분소득 대비 총부채액)와 부채상환비(가처분소득 대비 부채상환액)가 높아질수록 부부폭력의 위험도 증가하는 경향이 있었 다. 비빈곤층에서는 높은 부채상환비가, 빈곤층에서는 높은 비우량부채비가 부부폭력의 위험을 높이는 것으로 나타났다. 물질적 결핍의 매개효과 역시 빈곤지위에 따라 달랐는데, 빈곤층에서는 물질적 결핍이 비우량부채비와 부부폭력의 관계를 매개하는 것으로 보이나, 비빈곤층에서는 그러한 관계가 관찰되지 않았다. 이 연구는 경제적 곤란이 부부관계의 질에 영향을 미친다는 가족스트레스모델을 가계부채의 역할에 초점을 맞추어 적용하고, 경제적 곤란을 야기하는 다양한 요인 중 부채 부담 수준이 부부폭력의 위험에 미치는 영향을 실증분석 하였다는데 의미가 있다.

• 아태비즈니스연구
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• 제14권2호
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• pp.1-15
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• 2023

Purpose - This study investigates whether the inventory levels of Korean manufacturing firms increased or decreased from 2000 to 2019. We also explore the relationship between inventory levels and firm performance. Design/methodology/approach - We use panel data on KOSPI-listed firms in the manufacturing industry. We measure days in inventory as a proxy for inventory levels, and firm performance is measured by return on assets, return on sales, and EBITDA ratio. The panel data regression method is employed in our analysis. Findings - We find that days in inventory of Korean manufacturing firms significantly increased from 2000 to 2019, especially for raw materials and finished goods inventory. In addition, while days in inventory of large- and medium-sized firms were less than those of small-sized firms, the change in days in inventory of large- and medium-sized firms was positively significant over time. Moreover, the increase in days in inventory was more prevalent among industries related to foods, clothes, chemicals, and transportation. Finally, we show that the days in inventory are negatively related to firm performance. Research implications or Originality - While the Korean manufacturing industry has enormously grown over the last 20 years and managing inventory is critical in the manufacturing industry, our findings counter-intuitively show that the days in inventory of the Korean manufacturing industry had been gradually increased. We speculate that the increase in days in inventory is due to the Korean manufacturing firms' heavy reliance on global supply chains.

• 산경연구논집
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• 제5권1호
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• pp.5-9
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• 2014

Purpose - This study aims to examine the incremental information content of cash flw from operations and earnings in the Iranian capital market. Design, methodology, and approach - Based on market-based accounting research, this study uses statistical associations between accounting data (earnings and cash flw) and stock returns to assess/measure the incremental information content (value relevance) of cash flw and earnings. A multivariate regression model based on panel data is used to examine the incremental information content of earnings and cash flow from operations. Results - The results show that both earnings and cash flow from operations have incremental information content beyond each other. These results are consistent with the findings of recent studies. Overall, the fidings of this study support the usefulness of cash flw information in addition to earnings, in fim valuation by investors in the Iranian market. Conclusions - The study makes the following contributions to the Iranian literature on incremental information content of cash flw and earnings. First, this study employs actual cash flw data derived from cash flw statements. Second, this study employs a large sample size for a more recent period.

• The Journal of Asian Finance, Economics and Business
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• 제8권3호
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• pp.895-904
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• 2021

This study aims to investigate the impact of innovation on firm efficiency. Panel data of fourteen finance companies and nine technology companies from 2011 to 2019 on the Vietnam Stock Exchange Market is derived from audited financial statements, annual reports, and other crucial reports that are provided by Vietstock; macroeconomic variables are collected from the World Bank Database. A two-stage approach is used. First, use of the Data Envelopment Analysis methodology to measure firm efficiency. Second, use of the Pooled ordinary least squares, the Fixed effects model, and the Random effects model to investigate the impact of innovation on firm efficiency. Furthermore, the Generalized Method of Moments and the Tobit model are used to validate the impact of innovation on firm efficiency, and the t-test is used to confirm the difference in efficiency with and without the impact of innovation between two industries. The results show that there is a significant impact of innovation on efficiency, and innovation plays a more important in increasing the efficiency of the finance industry than the technology industry. Moreover, the relation between age and efficiency is like the U-shaped, and between size and efficiency is like the inverted U-shaped, whereas efficiency is not associated with inflation.

• Nuclear Engineering and Technology
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• 제55권5호
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• pp.1878-1884
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• 2023

To lay a solid basis for prosperity and competitiveness, countries should achieve balance in the three fundamental aspects: energy availability, energy affordability and ecological balance. Nuclear energy has attracted international interest as one of the most crucial environmental quality strategies. The objective of this study is to analyze the non-linear link between nuclear energy and environmental quality in the top-10 nuclear energy consumer countries (USA, China, Russia, France, Canada, Spain, Sweden, South Korea, Ukraine, and Germany). Earlier research employed panel data methodologies to examine the linkage between nuclear energy and the environment, despite the fact that many nations did not independently demonstrate such a correlation. On the alternative, this study uses a novel approach known as 'Quantile-on-Quantile,' which allows for the analysis of time-series dependence in each country by giving universal yet country-specific insights into the relationship between the variables. Estimates show that the consumption of nuclear energy improves environmental quality by lowering ecological footprint in the majority of the nations studied at certain quantiles of data. Moreover, the data demonstrate that the degree of asymmetries between our variables changes by nation, emphasizing the importance of policymakers exercising caution when adopting nuclear energy and environmental quality regulations.

• Structural Engineering and Mechanics
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• 제64권1호
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• pp.93-107
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• 2017

The article presents the vibration and acoustic responses of un-baffled doubly curved laminated composite panel structure under the excitation of a harmonic point load. The structural responses are obtained using a simulation model via ANSYS including the effect various geometries (cylindrical, elliptical, spherical and hyperboloid). Initially, the model has been established by solving adequate number of available examples to show the convergence and comparison behaviour of the natural frequencies. Further, the acoustic responses are obtained using an indirect boundary element approach for the coupled fluid-structure analysis in LMS Virtual.lab by importing the natural frequency values. Subsequently, the values for the sound power level are computed using the present numerical model and compared with that of the available published results and in-house experimentally obtained data. Further, the acoustic responses (mean-square velocity, radiation efficiency and sound power level) of the doubly curved layered structures are evaluated using the current simulation model via several numerical experimentations for different structural parameters and corresponding discussions are provided in detail.

• 아동학회지
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• 제30권3호
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• pp.113-125
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• 2009

This study advances knowledge of developmental patterns in poverty and delinquency; data was obtained from waves 1-5 (2003-2007) of the Korea Youth Panel Survey. Semi-parametric group-based modeling (SGM) identified 4 trajectories of poverty from age 13 to 17 : non-poor, poverty increasing, low-level continuous poverty and chronic poverty groups and five developmental trajectories of delinquency : non-offending, late onset, low-level continuous, desisting, and chronic groups. A joint trajectory method predicted patterns of delinquency conditional on poverty trajectories. Chronic and low-level continuous poverty groups were more likely than others to follow chronic trajectories of delinquency; the non-poor group was more likely to be non-offending. Implications of this study for youth welfare were discussed to reduce risk for delinquency.

• 전기학회논문지
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• 제59권7호
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• pp.1340-1345
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• 2010

FRC(Frame Rate Control) has been applied to the monitor and TV product as part of cost-saving in many flat panel display manufacturers. As FRC can represent the same number of gray scale level with bits of a smaller amount than bits of the input image data, it is widely used. However, FRC causes visual artifacts by using repeatedly pre-designed the FRC unit size of block pattern in display devices. Therefore, this paper analyzes the cause of the visual artifacts. And in order to improve them, it proposed the pattern arrangement of FRC unit blocks through frame rolling method as analytic solution for the first time. So, we could embody causes of FRC noise. Using the proposed structure, more robust pattern to FRC noise will be designed.

• 지능정보연구
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• 제21권4호
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• pp.93-110
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• 2015

기존의 협업필터링 추천시스템 연구는 상품에 대한 고객의 평점(rating)이나 구매 여부 데이터로부터 하나의 프로파일을 생성하고 이를 기반으로 추천 성능을 향상시킬 수 있는 새로운 알고리즘을 개발하는 위주로 진행되어 왔다. 그러나 빅데이터 환경이 도래하면서 기업이 수집할 수 있는 고객 데이터가 풍부해지고 다양해짐에 따라, 보다 정확하게 고객의 선호도나 행태를 파악하는 것이 가능하게 되었고 이러한 데이터, 즉 퍼스널 빅데이터(personal big data)를 추천시스템에 활용하는 연구의 필요성이 대두되고 있다. 본 연구에서는 마케팅의 시장세분화 이론에 근거하여 퍼스널 빅데이터로부터 고객의 선호도나 행태를 다양한 관점에서 표현할 수 있는 5종의 다중 프로파일(multimodal profile)을 개발하고, 이를 활용하여 협업필터링 추천시스템의 성능을 개선하고자 한다. 제안하는 5종의 다중 프로파일은 프로파일 통합 유사도, 개별 프로파일 유사도 평균, 개별 프로파일 유사도 가중 평균이라는 세 가지 앙상블 기법을 통해 협업필터링의 이웃(neighborhood) 탐색과정에 적용된다. 실제 퍼스널 빅데이터에 본 연구에서 제안하는 방법론을 적용한 결과, 단일 프로파일을 사용하는 협업필터링 알고리즘보다 추천 성능이 상당히 개선되었으며 앙상블 방법 중에서는 개별 프로파일 유사도 가중 평균 기법이 가장 높은 추천 성능을 보여주었다. 본 연구는 빅데이터 환경에서 추천시스템을 개발하고자 할 때, 어떠한 성격의 데이터로부터 고객의 특성을 규명하는 프로파일을 만들고 이를 어떻게 결합하여 사용하는 것이 효과적인 지 처음으로 제안하였다는 점에서 그 의의가 있다.