• 대한기계학회논문집A
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• 제26권4호
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• pp.731-738
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• 2002

To understand failure behavior of pipe thinned by flow accelerated corrosion, in this study, the pipe failure tests were performed on 102mm-Sch.80 carbon steel pipe with various local wall thinning shapes, and the failure mode, load carrying capacity, and deformability were investigated. The tests were conducted under loading conditions of 4-points bending and internal pressure. The experimental results showed that the failure mode of thinned pipe depended on magnitude of internal pressure and thinning length as well as loading direction and thinning depth and angle. The variation in load carrying capacity and deformability of thinned pipe with thinning length was determined by stress type appled to the thinning area and circumferential thinning angle. Also, the effect of internal pressure on failure behavior was dependent on failure mode of thinned pipe, and it promoted crack occurrence and mitigated local buckling at thinned area.

• 한국컴퓨터정보학회논문지
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• 제23권12호
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• pp.211-218
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• 2018

In this paper, we propose that investigating the relationship between the dynamic capacity and the technological innovation performance of firms. Based on the previous research, we divide the dynamic capacity into the adaptive capacity, absorption capacity, and productive capacity. Among the 3,400 companies responding to the technical statistics of SMEs in 2011, we performed multiple regression analysis with 2,807 except service industries. As a result, the absorptive capacity and productive capacity have a positive effect on the technological innovation performance at the 99% level, whereas the adaptive capacity has a negative effect on the technological innovation performance at the 95% level. The implications of this study are as follows. First, in order to improve the performance of technological innovation, it is important to strengthen the absorption capacity and productive capacity of companies. Absorption capacity shows that it is important to secure sufficient R & D manpower and R & D cost to utilize internal knowledge as well as to bring outside knowledge into the capacity to assimilate and utilize external knowledge. Second, the ability to commercialize a product is a capability to commercialize a technology that has succeeded in development, showing that the technology development organization must have the capability of post-development commercialization as well as technology development. Finally it shows the negative effect on adaptation capacity and innovation performance. Companies actively utilize external sources of information in order to respond to and adapt to the rapidly changing business environment. However, the results of this study show that a strategic approach is needed to use external sources of information and technology development resources. Especially as the use of external information resources and technology development resources increases.

• Geomechanics and Engineering
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• 제12권3호
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• pp.417-439
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• 2017

The stone columns are increasingly being used as a soil improvement method for supporting a wide variety of structures (such as road embankment, buildings, storage tanks etc.) especially built on soft soil. Soil improvement by the stone column method overcomes the settlement problem and low stability. Nevertheless, stone column in very soft soils may not be functional due to insufficient lateral confinement. The required lateral confinement can be overcome by encasing the stone column with a suitable geosynthetic. Encasement of stone columns with geogrid is one of the ideal forms of improving the performance of stone columns. This paper presents the results of a series of experimental tests and numerical analysis to investigate the behavior of stone columns with and without geogrid encasement in soft clay deposits. A total of six small scale laboratory tests were carried out using circular footing with diameters of 0.05 m and 0.1 m. In addition, a well-known available software program called PLAXIS was used to numerical analysis, which was validated by the experimental tests. After good validation, detailed of parametric studies were performed. Different parameters such as bearing capacity of stone columns with and without geogrid encasement, stiffness of geogrid encasement, depth of encasement from ground level, diameter of stone columns, internal friction angle of crushed stone and lateral bulging of stone columns were analyzed. As a result of this study, stone column method can be used in the improvement of soft ground and clear development in the bearing capacity of the stone column occurs due to geogrid encasement. Moreover, the bearing capacity is effected from the diameter of the stone column, the angle of internal friction, rigidity of the encasement, and depth of encasement. Lateral bulging is minimized by geogrid encasement and effected from geogrid rigidity, depth of encasement and diameter of the stone column.

• Tuberculosis and Respiratory Diseases
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• 제70권6호
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• pp.498-503
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• 2011

Background: The causes of exertional desaturation in patients with COPD can be multifactorial. We aimed to investigate factors predict exertional desaturation in patients with moderate to severe COPD. Methods: We tested 51 consecutive patients with stable COPD (FEV1/FVC, $40{\pm}13%$ predicted). Patients performed a six minute walk test (6MWT). Pulse oxymetric saturation (SpO2) and pulse rate were recorded. Results: Oxygen desaturation was found in 15 subjects after 6MWT, while 36 subjects were not desaturated. Lung diffusing capacity was significantly lower in desaturation (DS) group ($62{\pm}18%$ predicted) compared with not desaturated (ND) group ($84{\pm}20$, p<0.01). However there was no statistical difference of FEV1/FVC ratio or residual volume between two groups. The pulse rate change was significantly higher in the desaturated compared with the not desaturated group. Six minute walking distance, subjective dyspnea scale, airflow obstruction, and residual volume did not predict exertional oxygen desaturation. Independent factors assessed by multiple logistic regression revealed that a pulse rate increment (odd ratio [OR], 1.19; 95% confidence interval [CI], 1.01~1.40; p=0.02), a decrease in baseline PaO2 (OR, 1.105; 95% CI, 1.003~1.218; p=0.04) and a decrease in lung diffusing capacity (OR, 1.10; 95% CI, 1.01~1.19; p=0.01) were significantly associated with oxygen desaturation. Receiver operator characteristic (ROC) analysis showed that an absolute increment in pulse rate of 16/min gave optimal discrimination between desaturated and not desaturated patients after 6MWT. Conclusion: Pulse rate increment and diffusion capacity can predict exertional oxygen desaturation in stable COPD patients with moderate to severe airflow obstruction.

• 한국산학기술학회논문지
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• 제20권3호
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• pp.110-124
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• 2019

최근 몇 년 동안 병원의 과다 공급으로 인해 병원 관리가 어려워지면서 병원은 혁신적인 병원 경영을 도입하여, 고객 만족도를 높이고 있다. 이에 본 연구는 요양병원의 혁신성이 고객만족도에 미치는 영향에 대하여 병원의 내부역량과 입지전략의 매개효과를 중심으로 살펴 보았다. 연구의 대상은 서울 및 수도권 소재 요양병원 재원중인 환자 및 보호자 120명을 대상으로 선정하여 설문조사와 통계분석을 시행 하였다. 연구의 시사점은 다음과 같다. 첫째, 병원혁신성이 고객만족도에 유의한 영향을 주지 못하고 오히려 통계적으로 유의하지 않지만 부(-)의 영향을 미친다는 점에서 병원조직의 보수성 및 안정성에 대한 고객들의 기대를 확인할 수 있다. 일반기업과 달리 생명을 다루는 병원조직의 특성상 일반기업과 차별화된 병원조직 고유의 혁신성 측정도구 개발이 시급하다. 둘째, 혁신성이 내부역량과 입지전략에 미치는 영향력은 비슷했지만, 입지전략(${\beta}=0.357$)은 내부역량(${\beta}=0.283$)에 비해 고객만족도에 더 큰 영향력을 미치고 있음이 확인되었다. 요양병원의 경우 개원 시점부터 입지시장성, 교통인프라, 건물매력도, 의료집적성 등 입지요인에 근거하여 면밀한 준비가 선행되어야 한다는 점을 시사해 주고 있다. 셋째, 내부역량과 입지전략은 병원혁신성과 고객만족도 간의 관계를 완전매개하고 있음이 실증분석을 통해 확인되었다. 병원 혁신성은 유무형의 내부역량을 제고하고 있으며, 입지전략 수립을 위한 적극적 태도를 유도함으로써 고객만족도에 유의한 영향을 미치고 있음이 확인되었다.

• 보건의료산업학회지
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• 제7권1호
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• pp.69-82
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• 2013

The initial approach to this study is to focus on pharmaceutical companies' internal marketing activities for organizational diagnosis. By analysing the influence of internal marketing elements on the job satisfaction, organizational commitment, and turnover intention of pharmaceutical salespeople, this study aims at coming up with ways to strengthen the sales capacity and competitive edge of pharmaceutical companies through the salespeople's satisfaction. For 32 days between November 10th and December 12th of 2012, a total of 210 copies of questionnaires were given to the respondents and 203 of them except 7 with insufficient answers were used for the final analysis. The analysis result showed that internal communication, delegation of authority, and reward system among the elements of internal marketing activity had a positive influence on the workers' job satisfaction. The internal marketing activity elements did not influence the respondents' organizational commitment. Job satisfaction had a positive influence on their organizational commitment, while it had a negative influence of turnover intention. The conclusion section encapsulated the results of empirical analysis and proposed practical lessons regarding pharmaceutical companies' internal marketing.

• Geomechanics and Engineering
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• 제29권6호
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• pp.599-614
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• 2022

In this study, the reliability analysis of internal and external stabilities of Reinforced Soil Walls (RSWs) under static and seismic loads are investigated so that it can help the geotechnical engineers to perform the design more realistically. The effect of various variables such as angle of internal soil friction, soil specific gravity, tensile strength of the reinforcements, base friction, surcharge load and finally horizontal earthquake acceleration are examined assuming the variables uncertainties. Also, the correlation coefficient impact between variables, sensitivity analysis, mean change, coefficient of variation and type of probability distribution function were evaluated. In this research, external stability (sliding, overturning and bearing capacity) and internal stability (tensile rupture and pull out) in both static and seismic conditions were investigated. Results of this study indicated sliding as the predominant failure mode in the external stability and reinforcing rupture in the internal stability. First-Order Reliability Method (FORM) are applied to estimate the reliability index (or failure probability) and results are validated using the Monte Carlo Simulation (MCS) method. The results showed among all variables, the internal friction angle and horizontal earthquake acceleration have dominant impact on the both reinforced soil wall internal and external stabilities limit states. Also, the type of probability distribution function affects the reliability index significantly and coefficient of variation of internal friction angle has the greatest influence in the static and seismic limits states compared to the other variables.

• 한국재료학회지
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• 제28권3호
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• pp.129-134
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• 2018

This study was carried out to investigate the effect of grain size on the damping capacity of the Fe-26Mn-4Co-2Al damping alloy. ${\alpha}^{\prime}$ and ${\varepsilon}-martensite$ were formed by cold working, and these martensites were formed with a specific direction and surface relief. With an increase in grain size, the volume fraction of ${\alpha}^{\prime}$ and ${\varepsilon}-martensite$ increased by decrement the austenite phase stability. This volume fraction more rapidly increased in cold-rolled specimen than in the specimen that was not cold-rolled. The damping capacity also increased more with the augmentation an increased grain size and more rapidly increased in cold-rolled specimen than in the specimen that was not cold rolled. The effect of grain size on the damping capacity was larger in the cold-rolled specimen than the specimen that was not cold-rolled. Damping capacity linearly increased with an increase in volume fraction of ${\varepsilon}-martensite$. Thus, the damping capacity was affected by the ${\varepsilon}-martensite$.

• 한국해양공학회지
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• 제22권6호
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• pp.46-51
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• 2008

The effect of the addition of Co and N and subzero treatment on tensile strength and damping capacity was investigated in Fe-Cr-Mn alloy. Austenite was transformed into martensite by cold rollins increasing the degree of cold rollins led to an increase in the volume fraction of martensite. The damping capacity linearly increased with increasing volume fraction of ${\varepsilon}$ martensite in cold rolled specimens and subzero treated specimens after cold rolling. The volume fraction of ${\varepsilon}$ martensite, tensile strength and damping capacity was also increased by the addition of Co, while this treatment decreased the elongation. However, the volume fraction of ${\varepsilon}$ martensite, elongation and damping capacity were reduced by the addition of N, although the tensile strength increased. Tensile strength and damping capacity werealso increased by subzero treatment, while elongation decreased.

• 디지털융복합연구
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• 제14권10호
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• pp.195-203
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• 2016

본 논문은 정보화전략계획 수립에서의 환경 분석 단계를 빠르게 수행하여, 결과물에 대한 품질을 향상시킬 수 있는 기반을 마련할 수 있는 방법을 제안한다. 기존의 환경 분석 방법은 외부 환경 분석, 내부 역량 분석, 정보화 방향 도출 활동으로 구성되어 있다. 환경 분석 첫 번째 단계에 현황파악, 주요 프로젝트 이해관계자와 인터뷰 준비, 인터뷰 수행을 통하여 초기 정보화 방향을 획득하기 위한 활동들을 추가하였다. 그리고 외부 환경 분석, 내부 역량 분석을 위한 핵심 질문 중심의 융복합 시나리오 기반 분석 모형을 적용하였다. 분석모형으로 외부 환경 분석, 내부 역량 분석 활동을 수행하여, 도출된 정보화 방향을 초기에 설정한 정보화 방향과 검증할 수 있도록 하였다. 연구 결과는 실제 프로젝트 현장에 적용하여, 빠르게 프로젝트를 수행할 수 있었고, 프로젝트 결과물에 대한 품질을 향상시킬 수 있었다.