• 대한교통학회지
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• 제26권5호
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• pp.175-184
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• 2008

도로용량 증대를 위한 소요예산 추정문제는 관련주체인 이용자와 공급자의 입장을 모두 반영할 필요가 있다. 본 연구에서는 총통행시간, 형평성, 환경비용을 평가지표로 설정하고, 3가지 평가지표에 대한 관련주체의 요구사항이 만족되는 대안 중 소요예산을 최소화하는 최적 도로용량 증대 대안을 선정하는 문제를 모형화하였다. 일반적으로 도로용량 증대를 위한 소요예산 추정문제는 Network Design Problem(NDP)로 다루어지며, 이용자와 공급자의 다른 입장을 고려하기 위해 Bi-level 최적화문제로 모형화된다. 본 연구에서는 장래 교통수요의 불확실성을 반영하기 위해 확률모형(Stochastic model)을 적용하고, 평가지표별 신뢰도를 차별화하기 위해 Chance-constrained model(CCM)를 적용하였으며, 3가지 평가지표의 제약식을 만족하면서 소요예산을 최소화하는 목적함수를 만족하는 최적대안을 선정하기 위해 렉시코그라픽(Lexicographic) 최적화문제로 접근하였다. 예제 네트워크를 통하여 분석한 결과, 평가지표별 신뢰도 및 교통수요 변화율이 클수록 더욱 많은 소요예산이 요구되며, 평가지표별 신뢰도가 클수록 장래 교통수요의 변화에 더욱 탄력적으로 대응할 수 있는 대안이 선정되었다. 제안된 모델은 다양한 관련주체의 입장을 모두 고려한 최적 도로용량 증대 대안과 소요예산을 선정함과 동시에, 도로용량 증대량의 변화에 따른 평가지표간 상쇄관계(Tradeoff)와 도로 네트워크 개선을 위한 예산 배분의 포트폴리오를 정책결정자에게 제공 가능하다.

• International Journal of Concrete Structures and Materials
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• 제18권3E호
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• pp.207-211
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• 2006

This paper presents an experimental study on the repair performance of sprayed engineered cementitious composites(ECC) serving as a repair material. Sprayable ECC, which exhibit tensile strain-hardening behavior in the hardened state and maintain sprayable properties in the fresh state, have been developed by using a parallel control of micromechanical design and rheological process design. The effectiveness of sprayable ECC in providing durable repaired structures was assessed by spraying the ECC and testing them for the assessment. The experimental results revealed that, when sprayed ECC were used as a repair material, both load carrying capacity and ductility represented by the deformation capacity at peak load of the repaired flexural beams were obviously increased compared to those of commercial prepackaged mortar(PM) repaired beams. The significant enhancement in the energy absorption capacity and tight crack width control of the ECC repair system treated with wet-mix spraying process suggests that sprayed ECC can be effective in extending the service life of rehabilitated infrastructures.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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• pp.299-306
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• 2001

Crushed Stone Pile(CSP) is one of the ground improvement methods available to loose sand and clayey ground by forming compacted CSP in the weak soil layer. The effects of this method are enhancement of ground bearing capacity, reduction of settlement and prevention of lateral ground movement in cohesive layer, reduction of liquefaction potential in sandy ground. This study performs model tests in 1.0m${\times}$1.0m${\times}$1.0m and 1.5m${\times}$1.5m${\times}$l.2m model tank to observe bearing capacity of CSP treated ground. The area replacement ratio of CSP composite ground varies 20%, 30% and 40% with square grid pattern. After the composite ground was consolidated under pressure of 0.5kg/$\textrm{cm}^2$ and 1.0kg/$\textrm{cm}^2$, load tests were carried out. The results show that ultimate bearing capacity increases with area replacement ratio and the preconsolidation pressure of ground.

• 통합자연과학논문집
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• 제13권2호
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• pp.69-75
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• 2020

Multiple Input Multiple Output (MIMO) is one of the important wireless communication technologies. This paper proposes MIMO system capacity enhancement by using convolution of periodic circulating vector signals. This signal represents statistical dependencies between transmission signal with discrete noise and receiver signal with the linear shifting of MIMO channel capacity by positive extents. We examine the channel capacity, outage probability and SNR of MIMO receiver by adding log determinant signal with validated in terms of numerical simulation.

• Structural Engineering and Mechanics
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• 제72권6호
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• pp.723-736
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• 2019

The efficacy of a technique for the rehabilitation and strengthening of RC beam-column connections damaged due to cyclic loading was investigated. The repair mainly uses epoxy resin infused under pressure into the damaged region to retrieved back the lost capacity and then strengthening using fiber reinforced polymer (FRP) sheets for capacity enhancement. Three common types of reduced scale RC exterior beam-column connections namely (a) beam-column connection with beam weak in flexure (BWF) (b) beam-column connections with beam weak in shear (BWS) and (c) beam-column connections with column weak in shear (CWS) subjected to reversed cyclic loading were considered for the experimental investigation. The rehabilitated and strengthened specimens were also subjected to similar cyclic displacement. Important parameters related to seismic capacity such as strength, stiffness degradation, energy dissipation, and ductility were evaluated. The rehabilitated connections exhibited equal or better performance and hence the adopted rehabilitation strategies could be considered as satisfactory. Confinement of damaged region using FRP sheet significantly enhanced the seismic capacity of the connections.

• 대한통합의학회지
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• 제8권4호
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• pp.155-161
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• 2020

Purpose : This study was conducted to investigate the effect of positive active pressure technique and active breathing technique on lung function in healthy adults. Methods : In this study, the passive lung expansion technique and active respiration enhancement technique using an air mask bag unit were conducted in 30 normal adults to observe changes in pulmonary function with forced vital capacity (FVC), Forced expiratory volume at one second (FEV1). In order to observe the change in the level of respiratory function, we would like to investigate the peak expiratory flow (PEF) and the forced expiratory flow (FEF 25-75 %). Results : As a result of this study, there was no significant difference in comparison between the passive lung expansion technique and the active breathing enhancement technique (p>.05). The passive lung expansion technique effectively increased the effortful expiratory volume and the median expiratory flow rate of 1 second (p<.05). And the passive lung expansion technique effectively increased the effortless lung capacity and the maximum expiration flow rate (p<.05). Conclusion : The passive lung expansion technique effectively increases the range of motion of the lungs and chest cages, intrathoracic pressure, and elasticity of the lungs, and the active breathing technique increases the muscle functions such as the diaphragm and the biceps muscles. It is expected that it will be able to selectively improve the respiratory function of patients with respiratory diseases or functional limitations as it is found to be effective.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.157-162
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• 2001

The purpose of this study is to investigate the enhancement of shear capacity according to steel fiber contents in RC short columns. Lateral force resistance test was performed with the parameters of steel fiber contents in concrete volume. From the test results, shear and ductility capacity was improved with steel fiber contents Increased. In addition, an optimal steel fiber content was evaluated as a 1.5 % of concrete volume.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.48-51
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• 1996

A 5-bar structure with redundant actuators is proposed as a finger mechanism. It is shown that one additional redundant actuator greatly enhances the load handling capacity of the system. The actuator location should be carefully decided to maximize the performance enhancement. Furthermore, we develop stiffness and frequency control algorithms based on the internal loading created by redundant actuation. The effectiveness of these algorithms have been demonstrated by simulations.

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2004년도 제4회 발생공학 국제심포지움 및 학술대회
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• pp.88-88
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• 2004

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 추계 학술논문 발표대회
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• pp.239-241
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• 2012

The major industrialized nations have continued to develop industrialized construction techniques based on automated production processes in factories, and are applying them to a wide range of building. However, the unit modular construction system has had a shorter history of development and application in Korea compared to advanced countries, and consequently, Korean modular builders have a relatively poor technical capacity. So this study is draw a conclusion on the target of priority improvement for idea creation. It study on the enhancement of the functionality of the tool for assemble of Unit Modular that choose the enhancement of the functionality through the analysis of function on the three-level of functional definition and classification, functional arrangement, functional appraisal.