• Journal of Energy Engineering
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• v.24 no.1
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• pp.17-23
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• 2015

Electrical door system is one of the most essential items for the successful commercial operation of the railway vehicles. Nowadays, reliability values of electrical door system have a tendency to be included in technical requirements for design and manufacturing of rolling stocks. Manufacturer shall meet the reliability target values of electrical door system which is proposed by railway operator in procurement contract book. Railway operator shall approve the supplier's the reliability target values based on maintenance operation data. Railway operators are in the transition stage from the framework of maintenance interval based on time to the framework of maintenance interval based on distance. In this study, failure rates of the electrical door system currently used in railway vehicles are collected from maintenance field data. Failure rates are analyzed by using Minitab. Several kinds of plan for improving reliability are also suggested. It is necessary to keep studying on reliability prediction methodology, applying it in the field and implementing on improvement of reliability through feedback as well. Further, it will be useful for determining new maintenance policies or changing maintenance intervals for existing railway vehicles.

• Journal of the Korea Institute of Building Construction
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• v.10 no.2
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• pp.105-113
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• 2010

Method or work type improvement is needed in relation to reducing cost and increasing efficiency by ensuring construction quality and reducing labor in the form work process. This would have a great influence on the entire construction process, and make the process of adopting materials and methods more rational and economic. Hence, this study aimed to develop a Synthetic Resins Euroform that could improve durability, water-proofing, sophistication, and organizational unity through the use of injection modeling. Accordingly, this paper first investigated various performance requirements and necessary techniques, and then verified feasibility by evaluating the physical safety and technical validity when it is applied to construction field. In addition, this study evaluated the constructability, safety performance, environmental performance, and systemic excellence in terms of maintaining convenience of Synthetic Resins Euroform. Moreover, to verify feasibility in the construction field, this study analyzed and evaluated the maximum stress by measuring the load and deformation of the space of the horizontal furring, which is attached to Euroform as an armature.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.9
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• pp.1003-1008
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• 2012

The paper presents an Experimental Vehicle Model (EVM), that utilizes the kinematic characteristics of suspensions from SPMD test data. The relative displacement and orientation of a wheel with respect to the body are represented as a function of the vertical displacement of the wheel. The equations of motion of the vehicle are formulated in terms of local coordinates that do not require coordinate transformation, which improves the efficiency of dynamic analysis. The EOM was modularized for each suspension model, and a $6{\times}6$ vehicle model was obtained by combining six suspensions. The analysis results were compared with ADAMS to verify the accuracy of the EVM. This study also verifies the feasibility of real-time simulation with the developed EVM. For a vehicle simulation for 1 ms, the real simulation time required within 20% of the prescribed time. This result shows that the EVM meets the real-time simulation requirements.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.1
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• pp.1-12
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• 2017

Objectives: The major objectives of this study are to review the requirements for the advancement of occupational safety and health administrative organization and to propose measures to establish an Occupational Safety and Health Executive. Methods: The problems of occupational safety and health administrative organization in korea were examined empirically and cases of occupational safety and health administrative organizations in developed countries were investigated (United Kingdom, United States, Germany, and Japan). A plan for establishing an Occupational Safety and Health Executive was proposed over the short and medium term. Results: An occupational safety and health administration is characterized by a professional and technical nature, and even more so in modern society. Therefore the greatest value required by an occupational safety and health administrative organization is expertise. In addition, administrative values it requires include efficiency, specificity, independence, and activity. The Korean occupational safety and health administrative organization has a number of problems in terms of these values. The most appropriate way to realize these values is to establish an Occupational Safety and Health Executive. It is desirable to establish such an Occupational Safety and Health Executive in a phased manner taking into consideration its relationship with Korea Occupational Safety and Health Agency(KOSHA), including KOSHA's functional adjustment Conclusions: In order to solve the deep-seated problems in occupational safety and health administrative organization and to advance occupational safety and health administration in Korea, it is necessary to establish an Occupational Safety and Health Executive as a foundation for achieving an advanced industrial safety and health administration.

• Journal of the Korean Society for Heat Treatment
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• v.8 no.1
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• pp.32-43
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• 1995

Ti-6Al-4V alloy are widely used in chemical and aircraft industries for their good corrosion resistance and high strength to weight ratio. Surface alloying of Ti alloy by $CO_2$ laser is able to produce few hundred micrometers thick TiN surface-alloyed layer with high hardness on the substrate very simplely by injecting reaction gas($N_2$) into a laser-generated melt pool and adjust the hardness to the specific requirements of the individual application by changing of laser processing parameters. This research has been investigated the effect of such parameters on TiN surface-alloying of Ti-6Al-4V alloy by $CO_2$ laser. The maximum hardness of TiN surface-alloyed zone waw obtained by injecting 100% $N_2$ gas and it was decreased as the amount of $N_2$ gas in Ar and $N_2$ gas mixture was decreased. As scanning speed was increased, the hardness and depth of TiN surface-alloyed zone was decreased at constant laser power. The surface hardness after double scanning laser treatment is higher than that of single scanning. At constant laser power, the surface roughness is increased after the surface alloying if laser scanning speed is decreased.

• Journal of Energy Engineering
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• v.8 no.4
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• pp.525-532
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• 1999

The standardized Korea Next Generation Reactor (KNGR) NSSS has developed in the basis of the ABB-CE System 80+ design concept. In this study, several regulatory requirements for the KNGR shutdown cooling system (SCS) operation are investigated. The purpose of this study is to establish the technical self-reliance for SCS design by supporting fundamental data such as SDCHX effective area and reactor CCW flow rate. Thermal power of KNGR would be increased to about 4,000 $MW_{th}$ in comparison with thermal power 2.825 $MW_{th}$ of UCN 3&4, therefore, SCS design data shall b recalculated by using the KDESCENT Code, which could evaluate cooling capability of SCS. It is found that SCS minimum flow rate is able to remove the primary sensible heat. Reviewing the major components such as heat exchanger, pump, value, and operating procedure, it is concluded as follows.

• Journal of the Korean Society for Library and Information Science
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• v.43 no.3
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• pp.85-105
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• 2009

Disagreements between the technical environment and the conventional library catalog have caused a re-clarification of International Cataloguing Principles (ICP). Review is under way to finalize the publication of RDA (Resource Description and Access) in late 2009 by the Joint Steering Committee for Development of RDA. The impending RDA is based on FRBR (Functional Requirements for Bibliographic Records) which re-explains the bibliographic universe focused on entities, attributes and relationships between resources, but tries to maintain MARC as an encoding format for RDA. In this study, firstly FRBR, ICP and RDA were analyzed. Secondly, we propose 3 scenarios of RDA implementation: the future cataloging system based on the FRBR Entity, using a semantic web structure, and the scenario using the existing MARC format with some small changes. Finally, by examining response patterns of overseas bibliographic institutions, we present a set of urgent issues for future directions of bibliographic contro in Korea which includes, but not limited to, relationship between RDA/FRBR and KCR (Korean Cataloging Rules), continuation of KORMARC and authority control.

• Journal of Korean Society for Quality Management
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• v.49 no.3
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• pp.269-279
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• 2021

Purpose: The purpose of this study was to suggest weapon system specifications for requirements of Condition-Based Maintenance(CBM/CBM⁺). Methods: The military documents and case studies with regard to condition-based maintenance were reviewed. Representative Korea defense specifications of weapon system such as an aircraft, a C4ISR etc. were analyzed and investigated the level of requirement for maintainability was. Results: Condition-based maintenance was defined in both U.S. instruction and Korean directive. While deparment of defense(U.S.) provide a guidebook for CBM⁺, detailed instruction was not sufficient for Korean. Ministry of national defense(ROK) define the CBM⁺ by means of IPS element which should be developed along with the system development. The maintainability was barely included in Korean defense specifications, except for BIT(Built-in test) function. As a first step for defining the condition-based maintenance requirement in defense specification, this study suggests a standard form for data needed to acquire according to types of system, fault, failure, and so on. Conclusion: The empirical researches on CMB/CBM⁺ with domestic weapon systems are not enough, and a logic which leads the maintenance strategy to CMB/CBM⁺ is not solved. Through technical researches and institutional improvements including this study, we hope that condition-based maintenance would be fully established in the Korean defense field.

• Journal of Home Health Care Nursing
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• v.28 no.3
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• pp.317-328
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• 2021

Purpose: The purpose of this study is to provide patient-centered nursing by comparing the patient needs, patient satisfaction, and communication type of nurses for patients admitted to integrated nursing care service ward and general ward. Methods: Data were collected by self-report questionnaires between September 7 and October 9, 2021. Patients were patients recruited from a hospital in D city, 100 each from comprehensive nursing care service ward and general ward. The data were analyzed using descriptive statistics, 𝜒²-test, t-test, ANOVA, and Pearson's correlation. Results: There was no significant difference in patient needs between the patients of integrated nursing care service ward and the general ward (t=-1.12, p=.263). However, patient satisfaction was higher among the patients in integrated nursing care service ward than in the general ward (t=-3.55, p<.001). Pertaining to the communication type of nurses, the informational communication type (t=-4.02, p<.001) and the friendly communication type (t=-3.92, p<.001) were stronger in the integrated nursing care service ward than the general ward. It was, hence, confirmed that the educational requirements were positively correlated with patient satisfaction in the reliability domain and technical-professional domain, and that the nurse informational communication type and friendly communication type had a significantly positive correlation with patient satisfaction. Conclusion: The expansion of the integrated nursing care service ward may be considered in the future, with an informational and friendly communication method as an effective response that can be adapted in practice as a reflection the type of communication among nurses.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.15 no.1
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• pp.28-32
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• 2019

In nuclear power plant operation and spent fuel canisters, it is necessary to provide a sound technical basis for the safety and security of long-term operation and storage respectively. Recently, the peening technology is being discussed and the technology will be adopted to ASME Section III, Division 1, Subsection NX (2019 Edition). The peening is prohibited in current edition, but it will be approved in 2019 Edition and adopted. However, Surface stress improvement techniques such as the peening is used to mitigate SCC susceptible in operating nuclear plants. Although the peening will be approved to ASME CODE, there are no performance criteria listed in the 2019 edition. The Korean International Working Group (KIWG) formed a new Task Group named "Advanced Surface Stress Improved Technology". The task group will develop a CODE CASE to address PWSCC(Primary Water Stress Corrosion Cracking) and CISCC(Chloride Induced Stress Corrosion Cracking) for new ASME Section III components. TG-ASSIT was started to make peening performance criteria for ASME Section III (new fabrication) applications. The objective of TG-ASSIT is to gain consensus among the relevant Code groups that requirements/mitigation have been met.