• 혜화의학회지
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• 제10권1호
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• pp.1-11
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• 2001

Human nature, life, mind and spirit have very important meanings for Oriental medical science. This is because understanding human mind and spirit not only makes treatment of people easier and more accessible but also provides us a clue for finding out something we lost. As a consequence of investigating various classic books by ancient medical practitioners and Taoist scholars s as follows: l. Mind and spirit were valued very highly in Oriental medical science, and this can be found in classic books like , , , and . 2. To cure people, acquirement of detailed knowledge of mind and spirit should be preceded. 3. The Taoist school regarded mind, spirit, human nature and life as critical agents of health care and perceived that they were indispensable for going back to The Great Emptiness(Nothingness before the First Cause), the ultimate goal of Taoist learning. 4. Although human nature, life, mind and spirit have different names and different users, it is like theory and practice and we can see that ancient sages used them all in the same context of natural law.

• 한국재난정보학회 논문집
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• 제11권4호
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• pp.527-533
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• 2015

본 논문은 초기하중을 받는 역대칭 Cross-Ply 원통쉘의 동적특성을 고유진동수를 이용하여 해석하였다. 마주보는 두변이 단순지지된 적층 원통쉘의 운동방정식은 곡률항을 고려한 Mindlin 쉘이론과 에너지원리를 이용한 Rayleigh-Ritz법을 이용하여 유도하였다. 초기응력을 받는 적층쉘의 고유진동수, 임계좌굴계수 및 동적불안정영역 문제들을 무재하시의 무차원화 고유진동수로서 각각의 특성을 정립하였다. 본 연구에서 제안한 진동특성에 관한 간편산정식의 타당성과 사용성을 입증하기 위해 수치예를 들어 검토하였다.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2004년도 추계학술대회 및 정기총회
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• pp.535-538
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• 2004

Coordination between supply chain partners is viewed critical to effective supply chain management. Depending on the bargaining power balance between them, it is determined who will be able to exert more influence in making decisions related with such coordination. We consider two cases of the decision-making structure in the context of a simple supply chain consisting of two players, i.e., (1) the first case in which a supply chain partner dominates the decision-making process and the other passively follows the dominant player's decision, and (2) the other case in which the two players share the decision-making process equally. In this paper, we examine which of the cases is better for the companies and where comes the value of the better case. To answer the research questions, we set up an optimal control theory model and derive an analytical solution. The analysis outcome indicates that the shared decision-making in general produces better results for both companies in the supply chain, and the value of the shared decision-making comes from more effective resource utilization than the dominated case.

• 한국경영과학회지
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• 제28권2호
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• pp.17-33
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• 2003

The explosive growth of the internet-based transactions requires not only a secure payment system but also an appropriate trust measuring methodology and secure transaction protocols to guarantee the minimal risk for the transacting entities involved in specific transactions. Especially, in internet auction systems where either buyers or sellers or both can be more than one in one transaction, providing those systems that make sure no one transacting entity takes a major risk becomes critical. In this paper, an improved trust measuring method using a relationship-based internet community for an auction system is proposed. The proposed system incorporates fuzzy set and calculation concepts to help build trust matrices and models, which is used to measure the level of risk involved in a specific auction trade concerned. Also, to optimize the auction trade process in terms of cost and time, the proposed system recommends a differentiated trade protocol according to the risk level involved in each auction trade. To test the appropriateness of the proposed trusted auction system, a prototype system has been developed under a Windows-NT environment.

• 한국경영과학회지
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• 제39권2호
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• pp.131-140
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• 2014

Customer networks go through constant changes. They may expand or shrink once they are formed. In dynamic environments, it is a critical corporate challenge to identify and manage influential customer groups in a cost effective way. In this context, we apply inverse optimization theory to suggest an efficient method to manage customer networks. In this paper, we assume that there exists a subset of nodes that might have a large effect on the network and that the network can be modified via some strategic actions. Rather than making efforts to find influential nodes whenever the network changes, we focus on a subset of selective nodes and perturb as little as possible the interaction between nodes in order to make the selected nodes influential in the given network. We define the following problem based on the inverse optimization. Given a graph and a prescribed node subset, the objective is to modify the structure of the given graph so that the fixed subset of nodes becomes a minimum dominating set in the modified graph and the cost for modification is minimum under a fixed norm. We call this problem the inverse dominating set problem and investigate its computational complexity.

• The Korean Journal of Pain
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• 제27권3호
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• pp.200-209
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• 2014

Background: Spinal opioid administration is an excellent option to separate the desirable analgesic effects of opioids from their expected dose-limiting side effects to improve postoperative analgesia. Therefore, physicians must better identify either specific opioids or adequate doses and routes of administration that result in a mainly spinal site of action rather than a cerebral analgesic one. Methods: The purpose of this topical review is to describe current available clinical evidence to determine what opioids reach high enough concentrations to produce spinally selective analgesia when given by epidural or intrathecal routes and also to make recommendations regarding their rational and safety use for the best management of postoperative pain. To this end, a search of Medline/Embase was conducted to identify all articles published up to December 2013 on this topic. Results: Recent advances in spinal opioid bioavailability, based on both animals and humans trials support the theory that spinal opioid bioavailability is inversely proportional to the drug lipid solubility, which is higher in hydrophilic opioids like morphine, diamorphine and hydromorphone than lipophilic ones like alfentanil, fentanyl and sufentanil. Conclusions: Results obtained from meta-analyses of RTCs is considered to be the 'highest' level and support their use. However, it's a fact that meta-analyses based on studies about treatment of postoperative pain should explore clinical surgery heterogeneity to improve patient's outcome. This observation forces physicians to use of a specific procedure surgical-based practical guideline. A vigilance protocol is also needed to achieve a good postoperative analgesia in terms of efficacy and security.

• 한국IT서비스학회:학술대회논문집
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• 한국IT서비스학회 2008년도 추계학술대회
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• pp.153-156
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• 2008

In recent years, IPTV attracts great attention along with the digital convergence of communication and media technologies. IPTV combines the advantages of TV and Internet and changes our lifestyle dramatically. In addition, the IPTV service is capable of becoming a new business model which has huge growth potentials in technology-converging marketplaces. This study examines critical factors on the consumer's adoption of the IPTV service. Based on the Innovation Diffusion Theory (IDT), IPTV specific attributes and personal characteristics, we derive eight key factors in the research model. compatibility, ease of use, image, diversity of contents, interactivity, monetary value, social influence, and user satisfaction. Using the partial least square (PLS) method on the data collected through a web-based survey, we test our research model with several hypotheses. From this study, we find that diversity of contents, compatibility and interactivity have a significant indirect effect on the use of IPTV service via user satisfaction, and user satisfaction and social influence also have a significant direct impact on the IPTV use. These findings not only provide practical insights on the consumer acceptance of new technology-converging services, but also help managers to plan their marketing strategies better.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1328-1339
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• 2008

For a commonly used piezocone with a shoulder filter element, dilatory dissipation behavior, which shows an initial temporary increase in pore pressure, has been observed in overconsolidated cohesive soils. However, there is no appropriate way to estimate a consolidation parameter from a dilatory dissipation curve because currently available interpretation methods were developed based on the monotonic decrease of the excess pore pressure. In this study, the interpretation method for evaluation of coefficient of consolidation from a dilatory dissipation result of piezocone test was developed by performing the finite difference analysis on the dissipation after cone penetration. The distribution of the initial excess pore pressure induced by cone penetration, which is the core of the analysis, was estimated from the empirical modification of a solution proposed by cavity expansion theory and critical state concept. And the proposed interpretation method was applied to the field piezocone data and the results were compared to those obtained from laboratory tests. Its reliability was confirmed by the insignificant difference between the values of coefficient of consolidation from piezocone tests and laboratory consolidation tests.

• Structural Engineering and Mechanics
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• 제25권4호
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• pp.383-403
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• 2007

The contact problem for an elastic layer resting on an elastic half plane is considered according to the theory of elasticity with integral transformation technique. External loads P and Q are transmitted to the layer by means of two dissimilar rigid flat punches. Widths of punches are different and the thickness of the layer is h. All surfaces are frictionless and it is assumed that the layer is subjected to uniform vertical body force due to effect of gravity. The contact along the interface between elastic layer and half plane will be continuous, if the value of load factor, ${\lambda}$, is less than a critical value, ${\lambda}_{cr}$. However, if tensile tractions are not allowed on the interface, for ${\lambda}$ > ${\lambda}_{cr}$ the layer separates from the interface along a certain finite region. First the continuous contact problem is reduced to singular integral equations and solved numerically using appropriate Gauss-Chebyshev integration formulas. Initial separation loads, ${\lambda}_{cr}$, initial separation points, $x_{cr}$, are determined. Also the required distance between the punches to avoid any separation between the punches and the layer is studied and the limit distance between punches that ends interaction of punches, is investigated. Then discontinuous contact problem is formulated in terms of singular integral equations. The numerical results for initial and end points of the separation region, displacements of the region and the contact stress distribution along the interface between elastic layer and half plane is determined for various dimensionless quantities.

• Structural Engineering and Mechanics
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• 제74권1호
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• pp.83-90
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• 2020

Several classical and higher order plate theories were used to study the buckling of functionally graded material (FGM) plates. In the great majority of research, a power function is used to represent metal and ceramic material transverse distribution (P-FGM). Therefore, the effect of having other transverse variation of material properties on the buckling behavior of thick rectangular FGM plates was not properly addressed. In the present work, this effect is investigated using the Third order Shear Deformable Theory (TSDT) for the case of simply supported FGM plate. Both a sigmoid function and an exponential functions are used to represent the transverse gradual property variation. The plate governing equations are combined with a Navier type expanded solution of the unknown displacements to derive the buckling equation in terms of the pre-buckling in-plane loads. Finally, the critical in-plane load is calculated for the different buckling modes. The model is verified by a comparison of the calculated buckling loads with available published results of Al-SiC P-FGM plates. The conducted parametric study shows that manufacturing FGM plates with sigmoid variation of properties in the thickness direction increases the buckling load considerably. This improvement is found to be more significant for the case of thick plates than that of thin plates. Results also show that this stiffening-like effect of the sigmoid function profile is more evident for cases where the in-plane loads are applied along the shorter edge of the plate.