• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.36-36
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• 2016

하천정비나 유역종합 치수계획 등 수자원계획을 수립하는 과정에 있어 하천의 설계홍수량 추정은 필수적이며, 하천의 수공구조물의 안전성과 수문학적 위험도를 산정하는데도 활용되고 있다. 그러나 매년 관측되는 강우량 자료에 비해 유출량 자료의 길이가 비교적 짧아 신뢰성 있는 홍수량자료의 구축이 어려운 실정이며, 미계측 유역에 위치한 중소규모 하천의 설계홍수량과 같은 수문학적 자료는 매우 제한적이다. 이러한 이유로 본 연구에서는 기 수립된 하천정비기본계획의 자료들을 활용하여 유역의 특성(면적, 경사, 고도)이 고려되는 새로운 홍수량 산정식을 개발하였으며, Bayesian GLM(generalized linear method) 기법을 활용하여 미계측 유역의 지역화를 통한 홍수량의 추정이 가능하도록 하였다. 또한 Hierarchical Bayesian 기법을 활용하여 개발된 공식에 활용되는 매개변수의 불확실성을 구간을 산정하였다. Bayesian 기법의 도입으로 산정되는 홍수량의 불확실성 구간을 정량적으로 제시할 수 있었으며, 제안된 연구 결과는 미계측 유역의 홍수량을 추정하는 도구로서 활용성이 높을 것으로 기대된다.

• Korean Public Administration Review
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• v.48 no.3
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• pp.437-461
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• 2014

최근 재정건전성에 관한 논의가 확산되면서 비과세·감면제도는 유용성 관점에서 근본적인 변화를 요구받고 있다. 그럼에도 불구하고 정부는 경기부양 등 지역경제 활성화 도모차원에서 비과세·감면제도를 지속적으로 활용하고 있다. 이에 본 연구는 비과세·감면의 경제적 효과에 관한 분석의 필요성을 제기하며, 이를 위해 강원도 18개 시·군을 대상으로 지방세 비과세·감면이 지역경제에 어떠한 영향을 미치고 있는지에 관해 패널분석(PCSE)을 수행하였다. 패널분석 결과, 비과세·감면, 비과세, 감면 등이 지역경제에 미치는 영향은 다양하게 나타난다. 시 단위 지방자치단체의 경우 비과세·감면 규모가 증가될수록 지역경제에 정(+) 영향을 미치고 있다. 반면 군 단위 지방자치단체의 경우 변수 간 통계적으로 유의미하지 않아 비과세·감면정책이 지역경제를 활성화할 것이라는 정부의 주장은 다소 설득력이 낮다. 시 단위 지방자치단체의 경우 감면총액과 감면(조세특례제한법, 감면조례)규모가 증가될수록 지역경제에 정(+)의 영향을 미치지만, 지방세법 상 감면규모가 증가될수록 지역경제에 부(-)의 영향을 미치고 있다. 한편 군의 경우 지방세법 상감면규모가 증가될수록 지역경제에 정(+)의 영향을 미치지만, 감면조례에 근거한 감면규모가 증가될수록 지역경제에 부(-)의 영향을 미치고 있다. 분석결과에 근거한 정책적 함의는 다음과 같다. 정부는 지역경제 활성화를 위해 비과세·감면을 시행하면서 지방세수확충을 위해 또 다른 재정보전을 하고 있으나 지역경제에 미치는 영향이 그리 크지 않고 명확하지 않다. 따라서 비과세·감면의 규모를 줄이고 세수 확충을 통한 재정지출을 고려해야 한다. 특히 시 단위 지방자치단체의 경우 지방세법상 감면제도를 정비할 필요가 있고, 군 단위 지방자치단체의 경우 감면조례에 근거한 감면제도를 정비할 필요가 있다.

• Journal of Wetlands Research
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• v.19 no.3
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• pp.335-344
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• 2017

In this study, We proposed a method to estimate the design flood by area ratio in an ungauged basin. For that, the discharge parameters was determined by calibration of observed data at the watershed outlet and then peak flow was estimated by area ratio. In order to verify suggested method, peak flow was compared the observed discharge of the small river basin and the design flood discharge of river implementation projects. The results were summarized as follows. As a result of comparing the discharge by the area ratio and observed discharge, the difference of peak flows were analysed 14 ~ 25%. When the discharge calculated with area ratio of small river was compared with the design flood discharge of river implementation projects, the relative error was analyzed to be less than 20%. It means that suggested method in this study is appropriate.

• Journal of the Korea Society for Simulation
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• v.26 no.3
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• pp.35-46
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• 2017

Spare engine plays an important role for securing readiness of military strength during unexpected fault occurrences and field/depot planned maintenances. The purpose of this research is to present an approach towards the optimal number of spare engines/modules for diversity of aircraft types. We first reviewed two representative approaches, METRIC and meta model. We then investigated military aircrafts and categorized them into 5 types with regard to the engine type and number of engines/modules per aircraft. Through rigorous investigation of planned/non-planned maintenance of each type, we drew parameters and variables involved. As known, due to the complexity of the problem, it is impossible to develop a simple mathematical model with a closed form solution. Based on the airbase operation and maintenance logic with parameters/variable drawn, we developed a simulation model using ARENA well representing real field exercises. For the optimal solution, we applied OptQuest. It has shown that the program developed generates reliable results through a set of case examples.

• Korean Journal of Construction Engineering and Management
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• v.20 no.5
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• pp.104-114
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• 2019

This study explored to analyze the winning determinants of the lawsuit cases on the urban and housing redevelopment project based on jurimetric methods. Based on affirm-rate and staircase matrix tables, 441 lawsuit judgments are analyzed. Research findings in affirm-rate analysis indicate that past legal relation, no own defect of accreditation, no ownership or association member status, lapse of period of litigation, and no legal interest are identified as higher rate in order for the reason for plea on the merit. And so are defect on calculation of consent rate, defect in relation with written consent, approval before zoning designation, defect in relation with general meeting, and defect on zoning designation for the issue on the merit. It is noteworthy from the staircase matrix table analysis that the criteria for affecting the lawsuit outcome is determined based on key forecasting variables such as past legal relation and no ownership or association member status. This study intends to provide the implication that the unnecessary disputes can be reduced in the urban and housing redevelopment project by the implementation of jurimetric quantitative analysis methodology from the perspective of empirical law.

• Journal of Digital Convergence
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• v.12 no.12
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• pp.151-160
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• 2014

In terms of service quality evaluation, consumers think that the product they have bought is of good quality only when they are provided with satisfactory service. The purpose of this study was to examine the influence of service quality on customer satisfaction, repurchase intention and word-of-mouth intention in the automobile service industry and the possible mediating effects of Parameters by obtaining empirical data. A survey was conducted to gather data, and the collected data were analyzed by a statistical package SPSS. As a result, it's ascertained that the quality of service was one of integral factors for customer behavioral intention, and Parameters turned out to have strong mediating effects on the quality of service and customer behavioral intention as well.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.4
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• pp.355-362
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• 2012

Remaining useful life(RUL) prediction of a system is important in the prognostics field since it is directly linked with safety and maintenance scheduling. In the physics-based prognostics, accurately estimated model parameters can predict the remaining useful life exactly. It, however, is not a simple task to estimate the model parameters because most real system have multivariate model parameters, also they are correlated each other. This paper presents representative methods to estimate model parameters in the physics-based prognostics and discusses the difference between three methods; the particle filter method(PF), the overall Bayesian method(OBM), and the sequential Bayesian method(SBM). The three methods are based on the same theoretical background, the Bayesian estimation technique, but the methods are distinguished from each other in the sampling methods or uncertainty analysis process. Therefore, a simple physical model as an easy task and the Paris model for crack growth problem are used to discuss the difference between the three methods, and the performance of each method evaluated by using established prognostics metrics is compared.

• Journal of Korea Water Resources Association
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• v.48 no.3
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• pp.169-183
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• 2015

As a basic work for river restoration, analysis on fluvial geomorphological characteristics is made using past and present data to understand close-to-nature geomorphic status. The Miho and the Naesung Rivers are targets of this study. Fluvial geomorphic variables including valley-floor width, sinuosity, bankfull width, channel gradient, bed material size, bankfull discharge and unit stream power are evaluated with dominant processes. Though common sand-bed rivers with similar catchment area, the Miho and the Naesung Rivers are different in terms of valley-floor width, channel shape variables and dominant processes related with longitudinal location. In addition, analyses on interrelationship among the geomorphological variables are carried. Bankfull width is shown to be proportional to bankfull discharge, as is in a rough agreement with the previous studies. Relationship of bankfull discharge and channel gradient shows meandering and braiding are prevalent in the Miho River, whereas the most of the sub-reaches of the Naesung River fall to braiding. Relationship of channel gradient with width-depth ratio indicates dune-ripple processes are dominant in the Miho River, while the Naesung River shows longitudinal diversity from braiding in the downstream sub-reaches to riffle-pool and plane-bed along the upper ones. Analyses based on the past data on a river in a close-to-nature status are thought to be rather reasonable in comparison with those on the same river in a engineered condition.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1993.10a
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• pp.43-43
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• 1993

항공기 일정계획문제는 항공기, 승무원, 항공기 정비, 공항사용 등의 현재흐름을 시간과 공간의 개념을 도입한 Network상에 표현하여 분석하는 문제로서 여러가지 의사결정이 복합적으로 관련되어 있는 문제이다. 기존 연구에서는 운영상에 발생하는 많은 제약조건을 주어진 가정으로 처리하여 비교적 단순한 수리모형으로 최적해를 구하고자 했으므로 실제 적용에 한계를 가지고 있다. 또한, 최적해법으로 사용했던 최대흐름 알고리즘(Maximum Flow Algorithm)이나 단계적 접근법(Sequential Approach)으로는 변수의 수가 증가함에 따른 해법의 한계점을 가지고 있다. 본 연구에서는 1978년 미국의 항공규제완화 조치 후 많이 사용되고 있는 Hub and Spoke 노선상에서 항공기를 할당하는 문제로서, 보다 현실적인 제약요인을 포함하는 수리모형을 수립하고, Lagrangean Relaxation 기법을 사용하여 해를 구하고자 하였다.

• Journal of the military operations research society of Korea
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• v.36 no.2
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• pp.143-152
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• 2010

Military Power is the most direct and actual measures for national security. For construction, maintenance, management of military power, the adequate expenditure is required but it is difficult to increase blindly owing to the lack of resources. There are security threats and economic conditions in determining of military expenditure. Republic of Korea has been more influenced by economic conditions than by security threats since 1990s In this paper, we analysed relation between real military expenditure and real GDP through regression analysis.