• 대한토목학회논문집
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• 제38권6호
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• pp.967-977
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• 2018

건설현장에 숙련공 부족문제와 생산성 저하 문제가 지속적으로 제기되고 있으며, 이것에 대한 해결책의 하나로 건설자동화 기술도입이 검토되어 왔다. 이러한 배경에서 다양한 형태의 장비 및 시스템 개발이 이루어져 왔고, 특히 다수 및 다종의 건설장비가 투입되는 토공작업을 위한 개발이 많이 수행되었다. 하지만 개발된 장비나 시스템이 상용화 수준에 도달한 것은 매우 제한적이다. 그나마 단품 형태로 개발된 토공장비의 경우에는 현장에서 적용되고 있는 사례를 볼 수 있으나, 시스템 형태로 개발된 것은 각종 기능이 유기적으로 통합된 것이 아니라서 현장 테스트 단계에 머무르고 있다. 이러한 제약사항을 극복하고 제한된 예산과 연구기간을 고려할 때 어떤 기술분야의 어떤 요소기술들을 우선적으로 개발을 해야 하는지 전략이 필요하다. 본 연구에서는 상용화 수준의 토공시스템 개발을 위하여 필수적인 요소기술 분야와 세부 요소기술들을 설정하고 개발 우선순위를 결정하였다. 아울러 현재까지 개발이 완료된 토공시스템을 분석하고 이것에 근거하여 세부적인 개발방향을 제시하였다. 연구결과는 제한된 예산과 기간동안에 우선적으로 개발해야 할 기술을 설정하는데 사용될 수 있을 것이다.

• International Journal of Control, Automation, and Systems
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• 제6권6호
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• pp.928-938
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• 2008

This study presents an approach for approximation an unknown function from a numerical data set based on the synthesis of a neuro-fuzzy model. An adaptive input data space parting method, which is used for building hyperbox-shaped clusters in the input data space, is proposed. Each data cluster is implemented here as a fuzzy set using a membership function MF with a hyperbox core that is constructed from a min vertex and a max vertex. The focus of interest in proposed approach is to increase degree of fit between characteristics of the given numerical data set and the established fuzzy sets used to approximate it. A new cutting procedure, named NCP, is proposed. The NCP is an adaptive cutting procedure using a pure function $\Psi$ and a penalty function $\tau$ for direction the input data space parting process. New algorithms named CSHL, HLM1 and HLM2 are presented. The first new algorithm, CSHL, built based on the cutting procedure NCP, is used to create hyperbox-shaped data clusters. The second and the third algorithm are used to establish adaptive neuro- fuzzy inference systems. A series of numerical experiments are performed to assess the efficiency of the proposed approach.

• 한국정보과학회논문지:소프트웨어및응용
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• 제32권4호
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• pp.237-246
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• 2005

제품계열 공학(Product Line Engineering, PLE)은 핵심 자산을 이용하여 어플리케이션을 경제적으로 개발하는 대표적인 재사용 기술이다. PLE는 프레임웍(Framework) 공학과 어플리케이션 공학으로 구성된다. 프레임웍 공학은 한 도메인 내에 있는 여러 패밀리 멤버들이 가지고 있는 공통적인 기능인 핵심 자산을 개발하는 단계이고, 어플리케이션 공학은 핵심 자산을 패밀리 멤버에 맞게 인스턴스화하여 어플리케이션을 생산하는 단계이다. PLE는 핵심 자산을 이용하여 특정 어플리케이션을 개발함으로써 재사용성이 높을 뿐 아니라 어플리케이션을 적은 시간과 노력으로 만들 수 있으므로 개발하는 효율성도 높다. 그러나, PLE 개발 절차에 대한 산출물 정의 및 템플릿 제공이 미비하여 개발자들이 PLE 프로세스를 따라 산출물을 만드는데 어려움이 있고, 산출물간 관계 정의가 충분하지 못하여 산출물간 일관성을 유지하기 힘들어 개발자들은 PLE 프로세스의 실용적 적용에 어려움이 있다. 본 논문에서는 rLE의 핵심단계인 프레임웍 공학 과정의 각 단계마다 도출되는 산출물의 메타모델을 정의하고 각 산출물간의 추적 관계를 추적성 맵(Traceabitliy Map)으로 나타내며 산출물간 추적 관계를 적용할 수 있는 지침을 제시한다 마지막으로, 추적성 맵에 대한 평가와 적용되는 방법을 제시한다.

• Nuclear Engineering and Technology
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• 제24권2호
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• pp.111-120
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• 1992

본 논문은 안전정지지진에 대한 spacer grid충격하중의 동적특성을 고찰한 것이다. 안전정지지 진 (SSE： Safe Shutodown Earthquake)을 가진력으로 사용하였고 모델로는 가장 긴 15 row의 핵연료집합체 모델을 사용하였다. 외부에서 제공되는 입력데이타의 불확실성을 보상하기 위하여 흔히 사용되는 10%증가된 입력값과, NRC 권고사항인 입력응답스펙트럼의 이동효과의 영향이 평가되었다. 평가대상으로는 spacer grid의 충격력이 사용되었다. 해석결과로서 입력응답 스펙트럼의 이동효과의 영향은 거의 무시할 수 있으나 증가된 입력값의 영향은 spacer grid의 충격력에 큰 영향을 줌을 알 수 있었다. 따라서 원자로노심의 동적응답을 위해서는 입력응답 스펙트럼을 이동시키면서 해석할 필요가 없음을 확인하였다.

• 한국전문물리치료학회지
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• 제14권4호
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• pp.21-27
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• 2007

The purposes of this study were to compare core muscle activities with and without the use of Pilates resistive equipment during bridging exercises and to investigate the efficacy of a Pilates device. Fourteen healthy individuals (6 males, 8 females) between 20 to 26 years of age were examined. They were engaged in a bridging exercise with and without a magic circle. Three consecutive repetitions of each exercise were performed. Surface electromyography (sEMG) was used to measure the electrical activities of the right side internal oblique, the adductor longus, the multifidus, and the gluteus maximus muscles. Normalized EMG activities were compared using a paired t-test and the level of significance was set at =.05. The results showed that the EMG activities of the internal oblique (p=.0078), the adductor longus (p=.0007), and the gluteus maximus (p=.0001) muscles were significantly higher when using the magic circle during the Pilates bridging exercise. Also, statistically significant change existed in the multifidus muscle (p=.0106). The bridging exercise, combined with hip adduction using the magic circle, may enhance core stabilization. Therefore, using a magic circle during hip adduction combined with bridging exercise may be recommended usefully for individuals wanting to strength the core muscles. Further research is needed to access the nature of motor control of the Pilates mat exercises and to deliver exercise intervention for lower back pain patients.

• 한국통신학회논문지
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• 제41권12호
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• pp.1914-1924
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• 2016

본 논문은 5G 모바일 네트워크에서 가상화 기반의 이동통신 코어망인 Virtualized Evolved Packet Core(vEPC) 환경을 고려하여, 가입자의 종류 및 트래픽 식별에 따라 동적으로 End-to-end 서비스를 제공하기 위한 기술인 Service Function Chaining(SFC)을 적용하기 위한 구조 및 메시지 절차를 제안한다. SFC 기술은 네트워크 기능들을 물리적인 연결에 상관없이 선택적으로 제공하기 위한 기술로써, 가상화 기반 네트워크 기술인 Network Function Virtualization(NFV)기반의 네트워크 환경에서 서비스 제공을 위한 주요 기술로 예상된다. 특히, 5G 모바일 코어 네트워크는 분산 코어 형태로 구축될 것으로 예상되기 때문에 본 논문에서는 이를 고려하여 계층적 SFC(hSFC: Hierarchical SFC) 구조를 적용하였다. 본 논문에서는 제안하는 구조 및 구조 내에서의 SFC를 이용한 경로 설정 메시지 절차를 정의하고 오픈소스 기반의 테스트베드 설계를 통해 이를 구현하고자 하였다.

• Geomechanics and Engineering
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• 제23권1호
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• pp.61-69
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• 2020

The uniaxial compressive strength (UCS) of rock is a basic parameter in underground engineering design. The disadvantages of this commonly employed laboratory testing method are untimely testing, difficulty in performing core testing of broken rock mass and long and complicated onsite testing processes. Therefore, the development of a fast and simple in situ rock UCS testing method for field use is urgent. In this study, a multi-function digital rock drilling and testing system and a digital core bit dedicated to the system are independently developed and employed in digital drilling tests on rock specimens with different strengths. The energy analysis is performed during rock cutting to estimate the energy consumed by the drill bit to remove a unit volume of rock. Two quantitative relationship models of energy analysis-based core drilling parameters (ECD) and rock UCS (ECD-UCS models) are established in this manuscript by the methods of regression analysis and support vector machine (SVM). The predictive abilities of the two models are comparatively analysed. The results show that the mean value of relative difference between the predicted rock UCS values and the UCS values measured by the laboratory uniaxial compression test in the prediction set are 3.76 MPa and 4.30 MPa, respectively, and the standard deviations are 2.08 MPa and 4.14 MPa, respectively. The regression analysis-based ECD-UCS model has a more stable predictive ability. The energy analysis-based rock drilling method for the prediction of UCS is proposed. This method realized the quick and convenient in situ test of rock UCS.

• 산업경영시스템학회지
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• 제41권4호
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• pp.220-227
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• 2018

The cooperative game theory consists of a set of players and utility function that has positive values for a subset of players, called coalition, in the game. The purpose of cost allocation method is to allocate the relevant cost among game players in a fair and rational way. Therefore, cost allocation method based on cooperative game theory has been applied in many areas for fair and reasonable cost allocation. On the other hand, the desirable characteristics of the cost allocation method are Pareto optimality, rationality, and marginality. Pareto optimality means that costs are entirely paid by participating players. Rationality means that by joining the grand coalition, players do not pay more than they would if they chose to be part of any smaller coalition of players. Marginality means that players are charged at least enough to cover their marginal costs. If these characteristics are all met, the solution of cost allocation method exists in the core. In this study, proportional method is applied to EOQ inventory game and EPQ inventory game with shortage. Proportional method is a method that allocates costs proportionally to a certain allocator. This method has been applied to a variety of problems because of its convenience and simple calculations. However, depending on what the allocator is used for, the proportional method has a weakness that its solution may not exist in the core. Three allocators such as demand, marginal cost, and cost are considered. We prove that the solution of the proportional method to demand and the proportional method to marginal cost for EOQ game and EPQ game with shortage is in the core. The counterexample also shows that the solution of the proportional method to cost does not exist in the core.

• 한국전문물리치료학회지
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• 제28권1호
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• pp.59-64
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• 2021

Background: Hip flexor muscles are very important in the hip joint structure as a mover and stabilizer. In addition, isometric hip flexor strength in the supine position needs to be considered with isometric core strength (WICS) to measure a precise strength in a clinical way. Objects: We compared isometric hip flexor strength in the supine position in subjects with and without WICS (between factors) and conditions with and without an external support (within factors). Methods: A total of 34 subjects (16 with WICS, 18 without WICS) participated in this study. We used the double-bent leg-lowering test to divide the subjects in two groups according to the presence of WICS. Isometric hip flexor strength was evaluated in the supine position both with and without an external support condition. The two-way mixed analysis of variance was applied to identify significant differences between groups (with vs. without WICS: between factors) and conditions (with vs. without an external support: within factors). Statistical significance was set at α = 0.05. Results: In subjects with WICS, isometric hip flexor strength was greater with an external support than without it (p = 0.0064). In subjects without WICS, there were no significant differences in isometric hip flexor strength in the presence or absence of an external support (p = 0.075). The isometric hip flexor strength was significantly greater with an external support condition in particular in subjects with WICS. Conclusion: The findings of this study reported that an external support condition in individuals with WICS may contribute to the improvement of isometric hip flexion strength in the supine position. Therefore, isometric core strength should be evaluated to distinguish the weakness between core region and hip flexors.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 춘계학술대회
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• pp.47-47
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• 2020

The Korean National Agrobiodiversity Center holds the more than 1300 accessions of proso millet, but a large portion of accessions are landrace of Korea that has very similar traits. To comprehend the maximum genetic diversity of this crop, a core collection with minimum number of accessions will facilitate easy access to genetic material. Here we assessed the genetic diversity and population structure in a germplasm collection of 830 accessions by employing EST-SSR markers and morphological traits. A total of 107 alleles were detected with an average allele number of 4.9 per locus among the 830 accessions based on 37 EST-SSR markers. The number of alleles per locus ranged from 2 to 7. Polymorphism information content and expected heterozygosity ranged from 0.06 to 0.68 (mean = 0.21) and 0.06 to 0.73 (mean = 0.23), respectively. The germplasm collection was separated into two groups based on population structure analysis, whereas principal coordinate analysis (PCoA) could not cluster accessions according to their geographic origin. Subsequently, a preliminarily developed core collection with a total of 141 accessions (17%) was selected from the whole set of germplasm by combining allelic variations of EST-SSR markers and eight different phenotypic traits. The core collection optimally represented the whole germplasm collection and displayed a similar level of PCoA value and genetic variation from the initial collection. The results obtained here provide a primary resource for further genetic analysis and establish a reference for further development of appropriate genetic breeding strategies.