• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.617-631
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• 2019

In the four-step demand model, a gravity mode is used most commonly at the trip distribution stage. The purpose of this study was to develop a new friction factor that can express the accessibility property as a single friction factor to compensate for the variable limits of the gravity model parameters (travel time, travel cost). To derive a new friction factor, a new friction factor was derived using the space syntax that can quantify the characteristics of the urban space structure, deriving the link-unit integration degree and then using the travel time and travel distance relationship. Calibration of the derived friction factor resulted in a similar level to that of the existing friction factor. As a result of verifying the various indicators, the explanatory power was found to be excellent in the short - and long - distance range. Therefore, it is possible to derive and apply the new friction factor using the integration index, which can complement the accessibility beyond the limit of the existing shortest distance, and it is believed to be more advantageous in future utilization.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.411-411
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• 2021

최근 들어 이상기후에 따른 집중호우의 영향과 하천 유역 내에서의 토지이용의 증가로 하천의 하류부에서의 홍수피해는 점점 증가하고 있다. 이에 대비하기 위해 하천 시설물 설치를 계획하거나 이수, 치수 계획을 세우기 위해서는 하상이 어떻게 변화할 것인지 파악하는 것이 중요하다. 연구 대상 지역 세종특별자치시 금남면 영대리 유천천은 최근 10년간 홍수로 인한 피해액이 연평균 약 2.4억 원으로 나타났으며 매년 피해가 지속되고 있다. 유천천은 인위적 하도의 변경과 토지이용 상황의 변화 및 하천 골재채취, 댐 및 저수지 건설, 자연적인 홍수 등으로 하상이 변동되고 있으며, 그로 인해 생긴 유로의 변화로 발생할 수 있는 피해 예측이나 하천 시설물 설치를 위해서는 변동 결과의 예측이 필요하다. 따라서 본 연구에서는 대상 유역의 하상변동을 분석하기 위하여 HEC-RAS Sediment Transport Analysis(STA) 모형을 적용하였다. 적용한 데이터를 바탕으로 장래 하상변동 결과를 예측하였고 GIS 기법을 이용하여 유역의 특성 및 유출 특성에 관한 인자들을 도출하였다. 장래 1년, 5년, 10년 단위로 하상변동의 예측이 가능한 HEC-RAS STA 모형 분석 결과, 하상경사가 급한 각 하천상류 구간과 횡단시설물의 상류층에서는 하상저하가 발생하고, 하상경사가 완만한 하류 구간 부근에서는 일부 하상 상승이 발생하는 것으로 나타났다. 수위상승에 대비하여 지속적인 관찰과 상승구간에 대한 주기적인 하천 정비를 통하여 홍수기에 수위상승을 억제할 필요가 있을 것으로 판단된다. 본 연구의 결과는 하도 안정성과 이수와 치수안정성 확보, 하천의 효율적인 이용과 보전, 유지관리 시 기본해석으로 활용할 수 있을 것으로 사료된다.

• Proceedings of the Korean Society for Quality Management Conference
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• 2010.04a
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• pp.97-101
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• 2010

경제가 발달되고 경제의 기능이 전문화됨에 따라 다양한 지식서비스가 등장하고 있다. 실제로 우리 경제에서 지식서비스 산업이 차지하는 비중은 지속적으로 증가하고 있으며, 지식서비스 산업의 경쟁력이 나아가 국가 경제의 경쟁력이 되고 있다. 이러한 지식서비스 산업에 있어서 서비스 품질은 산업의 경쟁력을 결정하는 핵심적인 요소 중의 하나이다. 지식서비스 산업 중 세무대리, 회계, 특허, 컨설팅 등과 같이 자격증을 보유한 경영자가 운영하는 지식서비스 산업의 경우는 경영자의 리더십에 따라 서비스의 품질과 경영의 성과가 달라질 수 있다. 본 연구에서는 지식서비스 산업의 경영자의 리더십과 서비스 품질, 그리고 경영성과에 대한 구조적인 관계를 실증분석할 모형을 제시하고자 한다.

• Management & Information Systems Review
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• v.36 no.3
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• pp.113-130
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• 2017

This study examines the effect of direct investment in Asia on firm value for nonfinancial firms listed on KRX between 2006 and 2015. We also explore whether the mediating effects of cashholdings the relationship between direct investment in Asian markets and corporate value. Recently, companies are increasing their cash holdings for risk management. Cashholdings are causing agent problems, which has a negative impact on corporate value. In this case, when the company conducts active investment activities such as foreign direct investment, it is possible to supply the appropriate funds in a timely manner, thereby cashholdings increase the possibility of success of foreign direct investment and alleviate the agent problem of cash holdings. For the analysis, the number of directly invested firms in Korean listed firms is used as the explanatory variables for the Chinese and Vietnamese markets where foreign direct investment is the most active, and cash holding is set as the moderating variable. As a result, direct investment in China and Vietnam showed a positive (+) relationship with firm value, and cashholdings have a positive the relationship between foreign direct investment and firma value. The implications of this paper are as follows. First, it is suggested that the direct value of direct investment can be enhanced the relationship between direct investment and firm value in Asia. In addition, it can be suggested that cash holdings play a role of effective investment supply in firms that implement foreign direct investment, positively affecting corporate value.

• The Journal of Korean Academy of Sensory Integration
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• v.21 no.2
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• pp.45-57
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• 2023

Objective : The purpose of this study was to investigate the concurrent validity of the self- and proxy-report versions of the KIDSCREEN-10 quality of life questionnaire. Methods : A total of nine children and nine parents were selected to represent a cohort registered for a school-based wellness program. Two versions of the KIDSCREEN-10 questionnaire (self- and proxy reports) were administered to the children and their parents. The Rasch rating scale model was applied to determine the dimensionality and item difficulty of the two versions of the questionnaire. Moreover, the item-person matching map and Spearman's rho were compared to confirm the concurrent validity of the two versions. Results : All items, except four items (i.e., autonomy, home life, concentration/learning, and peers/social support), fit the Rasch rating scale model of the children's self-report version of the questionnaire. With regard to the parent's proxy-report version, two items misfit the model. While the items of the self- and proxy-report versions showed similar item difficulties, the parents had a tendency to be more severe in their ratings than the children. The correlation between the two versions was relatively low (Spearman's rho = .533, p > .05). The scatterplots between the two versions showed differences in the item difficulties of the physical and psychological well-being and self-perception items. Conclusion : These findings suggest that the three identified items should be taken into consideration when measuring children's health-related quality of life using the KIDSCREEN-10 questionnaire.

• Korea journal of population studies
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• v.30 no.3
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• pp.107-135
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• 2007

This paper uses a static Gamma count model, a traditional hurdle model and an endogenous switching Poisson model, respectively for determining married women's completed fertility rates in Korea. This paper analyzes the impact of household income, women's wage and education, and women's job market participation on the number of children of married women above age 40 and on the expected number of children of women aged below 40. The paper shows that a household income significantly increases the number of children for at least women aged above 40, however, this income effect is disappearing for younger generation. The empirical model suggests that women having a job tend to have fewer children for a group 39 years old and below and find that there is an endogeneity problem between child birth and labor force participation, too. The education level of married women gives a positive effect for giving a birth, itself, while it gives a negative impact on the number of children. Based on the empirical results, it concludes that Becker's Quantity-Quality theory works for Korea, too.

• Journal of Labour Economics
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• v.23 no.2
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• pp.1-37
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• 2000

Since the early 1990s, the Korean courts have tilted in the direction of giving greater freedom to employers by relaxing the restrictions on dismissal for economic reasons. During the Korean economic crisis of 1998, the Korean Labor Standard Act was also revised for the purpose of relieving the limitation of employer's discretion in employment adjustment. From the Coasian perspective, this article analyze how implied contracts for the employee's reliance and employer's compliance might be influenced after the formal law is revised. We demonstrate that, if the legal change results in excessive intervention, it might cause the employers to over-breach, the employees to under-rely, and the accompanying efficiency to decrease. We scrutinize the total population of unjust dismissal cases since 1987 in order to investigate how the legal changes in Korea have affected the implied contracts. Our empirical analysis raises a possibility that Korean legal changes made in 1990s might have increased the employer's opportunism and decreased the employer's reliance effort.

• Journal of the Korea Convergence Society
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• v.10 no.8
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• pp.217-226
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• 2019

This study examines the effect of the wedge between voting rights and cash flow rights of controlling shareholders on the implied cost of equity. Prior studies posit that controlling shareholder's voting rights exceeding cash flow rights causes expropriating minority shareholders. Using date from 793 group-affiliated Korean firms for 10 years from 2005 to 2016, the result shows that there is a positive and significant relationship between controlling shareholders' wedge and implied cost of equity. This result implies that investors regard the controlling shareholders' wedge as potential agency cost in which they require additional risk premium because controlling shareholders have a strong incentive to pursue their private interests trough tunneling practices.

• The Journal of the Convergence on Culture Technology
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• v.5 no.2
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• pp.77-82
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• 2019

The purpose of this study is to analyze the relationship between the controlling shareholding ratio and the business diversification of savings banks The difference in this study is the analysis of the relationship between the controlling shareholding ratio of the savings bank and the business diversification using panel data. In this study, the semi-annual financial statements for the period 2014-2018 were used on the basis of a sample of 79 saving banks. The research model is analyzed using random effects generalized linear square (GLS) model considering the autocorrelation problem. As a result of the empirical analysis, it is estimated that the relationship between the controlling shareholding ratio of the savings bank and the business diversification is significant (+). This is the result of supporting the hedging hypothesis.

• Proceedings of the Korea Contents Association Conference
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• 2011.05a
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• pp.201-202
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• 2011

본 연구에는 7.0T 동물용 자기공명영상장치를 이용하여 인간의 췌장암 세포인 CFPAC-1를 이종 이식한 쥐에서 자기공명영상을 획득하여 최적화된 검사 Protocol을 정립하며, 동물 실험에서 밝혀진 종양특성과 확산강조영상과의 비교 분석을 해보고 현성확산계수 영상이 췌장암 이종이식 모형의 종양 세포 내부 구조에 관하여 어떠한 정보를 제공 할 수 있는지 알아보고자 한다. 13마리의 쥐의 26개의 종양을 전형적으로 주입 후에 2~4주 뒤에 직경이 5~10mm가 되었을 때 imaged 하였으며, pathologic specimenm을 위해 sacrificed 하였다. isofluoran gas anesthesia를 이용하여 동물 마취 하였다. 사용된 장비로는 small-animal MR images (7.0-T)를 (Bruker BioSpin GmbH, Rheinstetten, Germany)이용하여 Fast T2-weighted 와 single-shot EPI DW image를 얻었다. 종양은 H&E 염색과 CD31와 VEGF에 대한 면역조직학 염색을 하여 종양의 cellularity와 microvessel density(MVD), 종양 내 괴사 정도를 평가하였다. CFPAC-1의 현성확산계수값은 $0.7327{\pm}0.1075{\pm}10^{-3}mm2/s$이였으며, 현성확산계수는 종양내 괴사 정도와 연관성을 보였다(R = 0.7417, p = 0.0001) 이처럼 현성확산계수는 종양 내 괴사 정도 등의 현미경적구조변화를 반영하는 대리인자로 사용될 수 있음을 확인하였다.