• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.7
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• pp.462-469
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• 2008

A regenerative evaporative cooler has been fabricated and tested for the evaluation of cooling performance. The regenerative evaporative cooler is a kind of indirect evaporative cooler comprised of multiple pairs of dry and wet channels. The air flowing through the dry channels is cooled without any change in the humidity and at the outlet of the dry channel a part of air is redirected to the wet channel where the evaporative cooling takes place. The regenerative evaporative cooler fabricated in this study consists of the multiple pairs of finned channels in counterflow arrangement. The fins and heat transfer plates were made of aluminum and brazed for good thermal connection. Thin porous layer coating was applied to the internal surface of the wet channel to improve surface wettability. The regenerative evaporative cooler was placed in a climate chamber and tested at various operation condition. The cooling performance is found greatly influenced by the evaporation water flow rate. To improve the cooling performance, the evaporation water flow rate needs to be minimized as far as the even distribution of the evaporation water is secured. At the inlet condition of $32^{\circ}C$ and 50%RH, the outlet temperature was measured at $22^{\circ}C$ which is well below the inlet wet-bulb temperature of $23.7^{\circ}C$.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.43
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• pp.175-195
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• 1997

The learning curve has an important effect the growth of corporation. But, in Korea, the study and inference on the learning rate of each industry are unprepared, and so, Korean industires have difficult in productivity and cost. At this point, this study infers the learning rate of the oil industries and investigates the productivity and growth of them. In conclusion, this study presents the direction of the oil industries' development. With the intention of this objects, this study seizes the status which is concerned the total quantity, the operating rate, the plant capacity, the indicators concerning productivity, the investment of R & D and the scales, and then, infers and verifies the relevancy in connection with the learning rate. In the oil industry, the average rate of learning is 65.96% from 1982 to 1994 which the total quantity and the average operation time are used to infer the rate. To observe the low rate within a same period of time, this study takes the consequences that the learning rate is almost indentical with them each year. This steady state is caused by a difference between the employee and the decision maker about the acquirement and assimiliated of technology. When the high-quality technologies posses the environment to applicate in the scene of labor with them, this technology applies to the productivities. As the learning rate increases, the productivity has more effectiveness. The result of analysis about the effectiveness of the learning rate follows that the R & D unfoldes to exist and does not contribute to the growth of the oil industry. To analyze the variables of the growth, such as the learning rate, the investement of R & D, the operating rate and the gross value added to property, plant and equipment, the model is established and examined. The business strategy in the oil industry must be developed to achive the internal growth as well as the external.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.5
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• pp.447-453
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• 2004

In this paper, we propose a new system to block harmful Internet information based on IP spoofing. The proposed system is located on a organization's internal network and monitors all outgoing traffic and lets all this traffic go outside. Once the proposed system detects a host's access to a harmful site, it sends the host a pseudo RST packet that pretends to be the response from the harmful site, and prevents the connection between the host and the harmful site. The proposed software system is installed on only a server, and need not be installed on user hosts at all. Thus we can maintain and upgrade the blocking system easily. The performance evaluation of the proposed system shows that it effectively blocks the access to the harmful sites. Since the proposed system is based on IP spoofing, it can be used badly as a hacking tool. Finally we propose some methods to eliminate this possibility.

• Journal of KIISE:Software and Applications
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• v.33 no.6
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• pp.525-538
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• 2006

Component-Based Software Engineering (CBSE) is widely accepted as new paradigms for building applications with reusable assets. Mismatch problems occur while integrating the assets and make a burden in CBSE. Therefore, a larger-grained reuse unit than a component such as a framework is required, and it consists of relevant components, connectors and domain-specific architecture. The benefits of frameworks over components are commonly known, however, the key elements and internal structure of framework has not been clearly defined. We believe most of the framework models proposed in recent works remain at conceptual level. In this paper, we propose a practical-level framework reference model, and define key elements of frameworks. The research goal is to precisely identify concrete elements of a framework, inter-connection of components within a framework, extended notion of connectors, and tailored meaning of architecture In a framework. Hence, the proposed framework can be practically implemented in common object-oriented languages and with middleware such as lava, J2EE, CORBA Component Model (CCM) and NET.

• Journal of the Society of Naval Architects of Korea
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• v.58 no.1
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• pp.49-57
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• 2021

In the production power transmitting of a floating production system like a wind offshore floating, the power cable should be connected from the surface system into the subsea system. The connection between the surface and the subsea system will make the power cable get a dynamic load like current and wave forces. Based on this condition, a dynamic power cable is required to endure external physical force and vibration in the long-term condition. It needs more requirements than static power cable for mechanical fatigue properties to prevent failures during operations in marine environments where the external and internal loads work continuously. As a process to verify, the durability test of dynamic power cables under the marine operation environment condition was carried out by using domestic technology development.

• Anxiety and mood
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• v.15 no.1
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• pp.1-12
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• 2019

Thought-action fusion (TAF) is a tendency to blindly assume causal relations between their thoughts and external reality. On the other hand, cognitive fusion (CF) is a tendency to take internal experiences, such as thoughts and feeling, literally rather than view them as random events. However, these two terms are often confusedly used and, in fact, have conceptual overlaps. Therefore, this study aimed to identify their distinctive features through a comprehensive review of the definition, origin, measurements and clinical implications especially on the understanding of obsessive-compulsive symptoms. The cognitive-behavioral concept of TAF is confined to erroneous and maladaptive beliefs about the connection between thoughts and behaviors. The CF is a broader construct that entails taking thoughts and feelings as facts and engaging or struggling with them such that the quality of life is lowered. They also have different theoretical backgrounds, developing processes and therapeutic approaches. From the perspective of the obsessive-compulsive disorder, both concepts have been studied as mid-structures for this illness. Recently, the effectiveness of psychological therapies related to these concepts such as defusion therapy has been tested. However, it is yet still in its infancy. In the future, complementary advances between the two concepts with studies on biological substrates is needed.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.6
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• pp.144-150
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• 2018

In this study, the freezing process of L-shaped pipe exposed to the outside was investigated numerically by considering the mushy zone of freezing water. From the numerical results, it was found that the flow was outwardly directed due to the influence of the L-shaped bending part in the outside exposed part of the pipe, and the ice was formed in the shape of longitudinal corrugation on the wall surface of the pipe after the bending part. It is confirmed that this phenomenon is caused by the venturi effect due to the freezing as seen in connection with the velocity distribution in the pipe. It is found that the remelting phenomenon at the end of the freezing section occur simultaneously during the process of forming the ice in the pipe section. In regard of the factors affecting freezing, it was found that the thickness of the freezing layer is increased as the exposed pipe surface temperature is decreased, and the pipe surface temperature had a significant effect on the change of the freezing layer thickness. At the same time, it was found that the freezing layer becomes relatively thin when the water inflow rate is increased. This phenomenon was caused by reducing the exposure time of freezing water due to the vigorous flow convection of the water fluid.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.823-824
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• 2016

In general, distribution board, panel board and motor control center can be installed over a wide area such as residence of group, building, schools, factories, ports, airports, water service and sewerage, substation and heavy industries that are used to supply converts the voltages extra high voltage into optimal voltage. There are electrical accidents due to rise of contact temperature, loose contact of bus bar, deterioration of the contact resistance, overtemperatue of the bus bars. In this paper, we propose bus bar joints monitoring system with loose connection of bus bar, measuring the joint resistance of busbars and monitoring internal and external heat. The proposed system can be reduced the electrical accidents by maintenance of busbar joints and the temperature of the conductive contact surface of busbars.

• International journal of steel structures
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• v.18 no.4
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• pp.1191-1199
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• 2018

Concepts of submerged floating tunnels (SFTs) for land connection have been continuously suggested and developed by several researchers and institutes. To maintain their predefined positions under various dynamic environmental loading conditions, the submerged floating tunnels should be effectively moored by reasonable mooring systems. With rational mooring systems, the design of SFTs should be confirmed to satisfy the structural safety, fatigue, and operability design criteria related to tunnel motion, internal forces, structural stresses, and the fatigue life of the main structural members. This paper presents a feasibility study of a submerged floating tunnel moored by an inclined tendon system. The basic structural concept was developed based on the concept of conventional cable-stayed bridges to minimize the seabed excavation, penetration, and anchoring work by applying tower-inclined tendon systems instead of conventional tendons with individual seabed anchors. To evaluate the structural performance of the new type of SFT, a hydrodynamic analysis was performed in the time domain using the commercial nonlinear finite element code ABAQUS-AQUA. For the main dynamic environmental loading condition, an irregular wave load was examined. A JONSWAP wave spectrum was used to generate a time-series wave-induced hydrodynamic load considering the specific significant wave height and peak period for predetermined wave conditions. By performing a time-domain hydrodynamic analysis on the submerged floating structure under irregular waves, the motional characteristics, structural stresses, and fatigue damage of the floating tunnel and mooring members were analyzed to evaluate the structural safety and fatigue performance. According to the analytical study, the suggested conceptual model for SFTs shows very good hydrodynamic structural performance. It can be concluded that the concept can be considered as a reasonable structural type of SFT.

• Journal of The Korea Institute of Healthcare Architecture
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• v.26 no.4
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• pp.15-26
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• 2020

Purpose: The purpose of this study is to derive a plan to establish a more sophisticated master plan so that the direction of master plan study can be sustained in the mid to long term. Methods:: Compare and analyze the differences between the master plan and the design to identify causes and problems. First, after establishing the master plan, compare the expansion area, net area per bed, and service area with the design drawing of the first project to determine the degree of recovery to the level required by the recent medical environment. Second, the possibility of responding to future internal changes is reviewed by comparing and analyzing the arrangement and connection method of extension buildings. Third, comparing the difference between the project following the first project and the phased of masterplan. Results: The first one is that continuous participation of person or group with high understanding of the master plan. Second, establishing a master plan and proceeding with the project through the determination of the correct business budget. Third, a specific area of the mechanical and electrical room suitable for the size and purpose of the hospital should be presented, and research on the arrangement method should be conducted. Finally, the feasibility of the hospital's own plan for securing parking facilities should be accurately investigated. Implications: It is important for the hospital to recover from the past to the present and respond to the future that the direction of the master plan continues after the establishment.