• Journal of Industrial Technology
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• v.43 no.1
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• pp.7-13
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• 2023

Nowadays, traffic congestion is emerging as a major problem due to the rapid population growth and the increase in automobiles. The train is a convenient means of transportation that can efficiently solve these problems. Trains have been developed in line with human aspirations for a long time, but research on safety is still insufficient. This study aims to check safety by conducting static tests and fatigue tests on bogie frames, and to help develop bogie frames in the future. For the static test, a strain gauge was attached to the point where the local stress concentration was expected beforehand, and the result value was derived, compared with existing theories, and expressed as a Goodman diagram. In the fatigue test, a total of 10 million loads were applied over three stages, and no cracks appeared in the non-destructive test conducted after each stage. Both tests were conducted according to the strict test method of the bogie frame presented by the UIC Code. It satisfied both fatigue life and strength evaluation criteria and was judged to be a bogie frame usable for safe train production.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.2
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• pp.379-386
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• 2007

Hado(河圖) and Laks${\u{\lrcorner}}$(書洛) are the diagrams composed of the symbols of numbers from one to ten. And the eight-trigrams, P'al-gwoe divide into two types one is a priori eight-trigrams (先夭八卦) or the Bok-Hui's eight trigrams(伏羲八卦); and the other is a posterior eight trigrams (後夭八卦) or the king Mun's eight trigrams (文王八卦). Relating these two diagrams of Hado and Laks${\u{\lrcorner}}$ with the two types of eight trigrams, they are said to be a term of Ha-Lak-Hui-Mun (HLHM). Each of HLHM represents the process of creating and changing of 'heaven and Earth' and every beingby the symbols of numbers and trigrams. In other words, each of HLHM symbolizes the origin and the structure of the universe as well as the birth of every life represented in the diagram of theosophany (福智學) or Kabbalah. HLHM are also regarded as the origin of l-ching or Book of Change. Hado produces Laks${\u{\lrcorner}}$ through the principle of yin-yang(陰陽). Laks${\u{\lrcorner}}$ produces a priori eight trigrams through the zigzag shapes which means Heaven and Earth are mutually responding. And a priori eight trigrams produce a posteriori eight trigrams through the triangle principle of connecting Heaven and Earth. In this process, Hado and a priori eight trigrams are respectively prior to Laks${\u{\lrcorner}}$ and a posteriori eight trigrams. HLHM represent fractal shape resembling the symbol of five on the center of Hado, or Hado itself. In the dynamic process of HLHM, a diagram of Circle, Quadrangle, and Triangle (CQT) is produced as follows: Circle, the symbol of 'infinify' or Heaven, represents the origin of life or birth. Hadois the symbol of creation. Quadrangle, the symbol of Earth, represents that Laks${\u{\lrcorner}}$is scattered into four directions of front, back, left, and rifht. Quadrangle, which is immovable, represents materiality. Triangle, being described from the eight trigrams, means the movements of the process of 'mutual inclusion' of Circle and Quadrangle. Triangle also means the process of harmonizing human beings with natural law.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.8
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• pp.913-920
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• 2011

We describe the evaluation of the fatigue life and strength of a lightweight railway bogie frame made of glass fiber/epoxy 4-harness satin-woven composites. To obtain the S-N curve for the evaluation of the fatigue characteristics of the composite bogie frame, we performed a tension-compression fatigue test for composite specimens with different stacking sequences of the warp direction, fill direction, and $0^{\circ}/90^^{\circ}$ direction. We used a stress ratio (R) of -1, a frequency of 5 Hz, and an endurance limit of $10^7$. The fatigue strength of the composite bogie frame was evaluated by a Goodman diagram according to JIS E 4207. The results show that the fatigue life and strength of the lightweight composite bogie satisfy the requirements of JIS E 4207. Given its weight, its performance was better than that of a conventional metal bogie frame based on an SM490A steel material.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.100-109
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• 2019

Maintainability indicates the extent to which maintenance can be done easily and quickly. The consideration of maintainability is crucial to reduce the operation and support costs of weapon systems, but if the maintainability is evaluated after the prototype production is done and necessitates design changes, it may increase the cost and delay the schedule. The evaluation should verify whether maintenance work can be performed, and support the designers in developing a design to improve maintainability. In previous studies, the maintainability index was calculated using the graph theory at the early design phase, but evaluation accuracy appeared to be limited. Analyzing the methods of evaluating the maintainability using fuzzy logic and 3D modeling indicate that the design of a system with good maintainability should be done in an integrated manner during the whole system life cycle. This paper proposes a method to evaluate maintainability using SysML-based modeling and simulation technique and fuzzy logic. The physical design structure with maintainability attributes was modeled using SysML 'bdd' diagram, and the maintainability was represented by an AHP matrix for maintainability attributes. We then calculated the maintainability using AHP-based weighting calculation and fuzzy logic through the use of SysML 'par' diagram that incorporated MATLAB. The proposed maintainability model can be managed efficiently and consistently, and the state of system design and maintainability can be analyzed quantitatively, thereby improving design by early identifying the items with low maintainability.

• Journal of Korean Academy of Nursing Administration
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• v.2 no.2
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• pp.43-57
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• 1996

The purpose of this research conducted has been an the development of a computer program to be used for nursing of spinal cord injury patients. The research is also intended to contribute by supplying the basic data, to the development of other programs in relevant areas where similar nursing information system is required. This research used System Development Life Cycle method. Results from the study were as follows : The scope of Information System in nursing practice were based on a wide range of mateials as charts at four hospitals in Pusan that cover the nursing period of spinal cord injury patients from admission to discharge and other sources of reference, the research is done for nursing diagnosis, nursing history, admission and discharge education, and the performing of doctor's order, which were divided into a subsystem that consisted of help, Patient Management, Performing of Docter's Order, and Basic Data Management and then these was analysed systematically using Hierachy Plus Input Process Output, necessary information, data flow diagram, and conceptual designs were developed for chosem system. Furthemore, the system has been programed by a conceptual design that includes the objects of the program and the origins of the sources. The oder to make sure of the proper function, the computer program was actually applied to a nursing practice that had been developed for a hypothetical situation through the two nurses who were in charge of spinal cord injury patients after they were trained to understand the structure and the contents of computer program about the nursing practice from using the computer program developed. Also, the compensatory strategy has been worked out against any problems to arise. It is expected that this kind of nursing practice information system to be used for the spinal cord injury patients that has been developed through the processes shown above will increase the satisfaction for both patients and nurses by enabling them to give more professional advice and service to the development of more information systems for many hospitals.

• Journal of the Korea Society for Simulation
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• v.18 no.4
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• pp.67-79
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• 2009

Because a product in the car industry has a short life cycle in recent years, the process planning and the manufacturing lines have to be changed frequently. Most of time, repositioning an existing facility and modifying used control information are faster than making completely new process planning. However, control information and control code such as PLC code are difficult to understand. Hence, industries prefer writing a new control code instead of using the existing complex one. It shows the lack of information reusability in the existing process planning. As a result, to reduce this redundancy and lack of reusability, we propose a SOS-Net modeling method. SOS-Net is a standard methodology used to describe control information. It is based on the Device Structure which consists of sensor information derived from device hardware information. Thus, SOS-Net can describe a real control state for automated manufacturing systems. The SOS-Net model is easy to understand and can be converted into PLC Code easily. It also enables to modify control information, thus increases the reusability of the new process planning. Proposed model in this paper plays an intermediary role between the process planning and PLC code generation. It can reduce the process planning and implementation time as well as cost.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.390-397
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• 2019

A mechanical model of band sawing saw frame was established according to an analysis of a commonly used saw-frame structure diagram to overcome the problems of low service life, substandard cutting precision and efficiency, and high manufacturing cost caused by the unreasonable design of saw frame. Taking a particular type of sawing machine as an example, stress cycle analysis of the saw blade was carried out according to the mechanical model of the saw frame, and the fatigue analysis model of the most dangerous cross-section point that was most prone to fatigue failure of the saw blade was then established. The fatigue analysis result was used as the basis for the improved design of the saw frame, and the improved detailed saw-frame design parameters were obtained. The results suggested that the saw frame system is much more compact and the saw blade force met the fatigue strength requirements through the improved design. In addition, the service life of the saw blade and the cutting precision were increased. The established mechanical model of the saw frame in this paper is used widely and has high practical application values.

• Korean Journal of Construction Engineering and Management
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• v.11 no.3
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• pp.43-54
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• 2010

As Urban Regeneration is being carried out, stakeholders are most likely to have disagreements on their interests. Besides, dispersion of numerous communication routes and obscure decision processes aggravate the situation. Eventually, fragmented decision-making processes and complex structure lead to inefficient outcome and delay of projects. This paper is a study on decision-making support not only helps the program manager have more efficient and optimum decision, but also provides alternatives for Urban Regeneration. This study is conducted as follows. Firstly, the project process and the decision-making structure among stakeholders in Urban Regeneration are analyzed, and then the current status of decision-making in Urban Regeneration project is classified. Secondly, with literature study on "Gateway Review", the decision-making gateway review process in Urban Regeneration is defined, and then the "Gateway Review Elements" are listed. Thirdly, to establish gateway review process, this paper presents a check points, namely gate which supports a program manager to monitor and to control the program management in Urban Regeneration. Each gate has several supporting tools such as diagram of critical decision points relation, scheme of stakeholder, checklist. Fourthly, the proposed concept is verified by experts who have been carefully selected to provide their respective reviews. Finally, decision-making support gateway review system is modified based on their critiques and suggestions.

• Korean Journal of Environment and Ecology
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• v.29 no.3
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• pp.353-367
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• 2015

The goal of this study is to analyze the feedback structure of habitat changes of the Whooper Swan in Eulsukdo using system thinking to suggest a management plan for ecosystem health. Using the causal loop diagrams of population changes between Whooper Swan and other bird species in Eulsukdo, we found that the environmental changes in the roosting and foraging area affect the Whooper Swan's population. The causal loop diagrams of the Whooper Swan's roosting area indicated that the environmental changes (e.g., water level, noise, bird watching, and other experience activities) may influence their population density variation. In addition, the casual loop diagrams of the Whooper Swan's foraging area showed that the Whooper Swan's population was affected by various variables that included area factors such as surface area of freshwater, frozen water, salinity, and density of Scirpus planiculmis. Furthermore, through the integrated causal loop diagram, cumulative discharge of Nakdong estuary weir and building activities were identified as the variables that affect the population of the Whooper Swan. Thus, we selected this area as the strategic point to establish a management plan for the Whooper Swan's habitat. The results of this study will help in decision making of a long-term management plan for sustaining the environmental health of the ecosystem in Eulsukdo.