• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.8
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• pp.94-102
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• 2002

Since it would be almost impossible to recover and/or repair the satellite in space once it has been launched, a detailed analysis and design, manufacturing using the high quality workmanship, and qualification and acceptance tests in space-simulation environments are necessary for all satellite components prior to launch. Even though these efforts arc made, the failure can still occur. Therefore, redundancy should be considered in the satellite design for continuous operations in preparation for part or equipment failure. In this paper, the reliability analysis of the transponder, which is a payload of Communications & Broadcasting Satellite being developed by ETRI, was performed and compared for various design cases with different redundancies to find the optimal design. The optimal design has been finalized by investigating how the redundant components are composed from the viewpoint of technical performance measures, such as reliability, cost, schedule, and mass.

• Journal of Korean Society for Geospatial Information Science
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• v.21 no.1
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• pp.65-75
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• 2013

In this study, one of the main aims is to build up a technical foundation for promoting the cadastral resurvey effectively and to improve the accuracy of cadastral surveying is to make use of precise surveying techniques in allowance of position errors as reference accuracy in cadastral resurvey, which is proper to obtain the sufficient accuracy of the cadastral control points, and parcel boundary points by introducing the GNSS-based surveying techniques on cadastral survey. In detail, the existing procedures and outcomes of cadastral survey were compared and analyzed for suggesting a better survey technique than that of the other techniques in a variety of aspects of capability of cadastral survey. The new skills and supports could be upmost importance when doing cadastral survey. What's more, essentially, 'The Measurement Department' makes all the efforts to establish 'The Surveying Regulations'. This could possibly apply GNSS-based surveying technique to the cadastral resurvey for the foreseeable future and this research paper suggested that how to improve absolute accuracy of cadastral reference points by means of putting to use the appropriate models of measurement further.

• Nuclear Engineering and Technology
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• v.47 no.1
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• pp.11-25
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• 2015

The accident at Japan's Fukushima Daiichi nuclear power plant in March 2011, caused by an earthquake and a subsequent tsunami, resulted in a failure of the power systems that are needed to cool the reactors at the plant. The accident progression in the absence of heat removal systems caused Units 1-3 to undergo fuel melting. Containment pressurization and hydrogen explosions ultimately resulted in the escape of radioactivity from reactor containments into the atmosphere and ocean. Problems in containment venting operation, leakage from primary containment boundary to the reactor building, improper functioning of standby gas treatment system (SGTS), unmitigated hydrogen accumulation in the reactor building were identified as some of the reasons those added-up in the severity of the accident. The Fukushima accident not only initiated worldwide demand for installation of adequate control and mitigation measures to minimize the potential source term to the environment but also advocated assessment of the existing mitigation systems performance behavior under a wide range of postulated accident scenarios. The uncertainty in estimating the released fraction of the radionuclides due to the Fukushima accident also underlined the need for comprehensive understanding of fission product behavior as a function of the thermal hydraulic conditions and the type of gaseous, aqueous, and solid materials available for interaction, e.g., gas components, decontamination paint, aerosols, and water pools. In the light of the Fukushima accident, additional experimental needs identified for hydrogen and fission product issues need to be investigated in an integrated and optimized way. Additionally, as more and more passive safety systems, such as passive autocatalytic recombiners and filtered containment venting systems are being retrofitted in current reactors and also planned for future reactors, identified hydrogen and fission product issues will need to be coupled with the operation of passive safety systems in phenomena oriented and coupled effects experiments. In the present paper, potential hydrogen and fission product issues raised by the Fukushima accident are discussed. The discussion focuses on hydrogen and fission product behavior inside nuclear power plant containments under severe accident conditions. The relevant experimental investigations conducted in the technical scale containment THAI (thermal hydraulics, hydrogen, aerosols, and iodine) test facility (9.2 m high, 3.2 m in diameter, and $60m^3$ volume) are discussed in the light of the Fukushima accident.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.33-37
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• 2006

Since 1993, the civil aviation community through RTCA (Radio Technical Commission for Aeronautics) and the ICAO (International Civil Air Navigation Organization) have been working on the definition of GNSS augmentation systems that will provide improved levels of accuracy and integrity. These augmentation systems have been classified into three distinct groups: Aircraft Based Augmentation Systems (ABAS), Space Based Augmentation Systems (SBAS) and Ground Based Augmentation Systems (GBAS). The last one is an implemented system to support Air Navigation in CAT-I approaching operation. It consists of three primary subsystems: the GNSS Satellite subsystem that produces the ranging signals and navigation messages; the GBAS ground subsystem, which uses two or more GNSS receivers. It collects pseudo ranges for all GNSS satellites in view and computes and broadcasts differential corrections and integrity-related information; the Aircraft subsystem. Within the area of coverage of the ground station, aircraft subsystems may use the broadcast corrections to compute their own measurements in line with the differential principle. After selection of the desired FAS for the landing runway, the differentially corrected position is used to generate navigation guidance signals. Those are lateral and vertical deviations as well as distance to the threshold crossing point of the selected FAS and integrity flags. The Department of Applied Science in Naples has create for its study a virtual GBAS Ground station. Starting from three GPS double frequency receivers, we collect data of 24h measures session and in post processing we generate the GC (GBAS Correction). For this goal we use the software Pegasus V4.1 developed from EUROCONTROL. Generating the GC we have the possibility to study and monitor GBAS performance and integrity starting from a virtual functional architecture. The latter allows us to collect data without the necessity to found us authorization for the access to restricted area in airport where there is one GBAS installation.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.4
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• pp.741-752
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• 2024

Organizations amplify their information security (IS) technical investments as the demand for IS escalates. This research suggests conditions for enhancing insider compliance with IS, focusing on the potential for behavior modification through techno-stress and organizational justice, based on the theory of planned behavior. To test the proposed hypothesis, this study utilized a survey methodology on 383 employees from companies with implemented IS. The test results showed that IS techno-stress (overload and uncertainty) caused by reduced attitudes of employees, and organizational justice increased subjective norms, influencing IS compliance intentions along with self-efficacy. Additionally, organizational justice has been found to alleviate the adverse effects of IS overload and uncertainty on attitudes. The findings are expected to help clarify measures for achieving IS performance within the organization by proposing organizational justice conditions to improve the negative IS environment of the organization.

• Korean Journal of Construction Engineering and Management
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• v.21 no.2
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• pp.47-58
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• 2020

The ICEC (Index of Construction Engineer's Competency) quantifies the competence of construction engineers using such parameters as experience, education, and qualifications and assigns four technical grades (expert, advanced, intermediate, and beginners) to construction engineers according to their scores for the efficient management and loading of technical personnel. However, as of 2020, the seventh year since its implementation, ICEC has shown many problems in its application, unlike its intended purpose. So institutional supplementation is required to provide improvement measures that can cope with the changing labor market environment and complement the current ICEC. Therefore, this study examined the current status of the career management system after the introduction of the ICEC, suggested a career index proportional to the competence of construction engineers from the beginner to the expert level, and developed an effective capability evaluation model I²CEC. The improved model presented in this study provides a means to comprehensively judge the performance, experience, and the professional work abilities of construction management engineers. Furthermore, the results of this study are expected to contribute to the development of efficient manpower and career management systems for enhancing the competitiveness of the domestic construction industry.

• Korean small business review
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• v.42 no.4
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• pp.147-172
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• 2020

This study presents the determinants of R&D efficiency as the focus on CEO's competency, which influences R&D competency and R&D efficiency. The research samples are 6,708 technology-innovation small and medium-sized enterprises (SMEs). The independent variable is the R&D competency(existence of R&D organization, level of R&D personnel, R&D personnel management, R&D investment), the dependent variable is R&D efficiency. The moderator is the CEO's competency(experience level in its own industry, technical knowledge level, technology management strategy, management ability). R&D efficiency measures the relationship between inputs(level of R&D personnel, R&D investment) and outputs(patent applications, prototype) by the DEA. and the determinant analysis uses Tobit regression. As a result of the analysis, the existence of R&D organization and R&D personnel management is positively significant, level of R&D personnel and R&D investment is negatively significant for R&D efficiency. The moderating effect of CEO's competency on the relationship between the R&D competency and R&D efficiency is significant determinants of CEO's experience(experience level in its own industry, technical knowledge level) and technology management strategy. The finding is to measure the efficiency of R&D performance, and to analyze its determinants as the moderating effect of CEO's competency, using the technology appraisal data. In the conclusion session, the limitations of the research and future research directions were discussed.

• The KIPS Transactions:PartD
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• v.13D no.4 s.107
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• pp.583-592
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• 2006

Software development based on product lines has been proved a promising technology that can drastically reduce cycle time and guarantee quality by strategically reusing quality core assets that belong to an organization. However, how to measure within a product line is different from how to measure within a single software project in that we have to consider the aspects of both core assets and projects that utilize the assets. Moreover, the performance aspects of overall project lines need to be considered within a product line context. Therefore, a systematic approach to measure the performance of product lines is essential to have consistent, repeatable and effective measures within a product line. This paper presents a context-based measurements elicitation approach for product lines that reflects the performance characteristics of product lines and the diversity of their application. The approach includes both detailed procedures and work products resulting from implementation of the procedures, along with their templates. To show the utility of the approach, this paper presents the elicited measurements, especially for technical management practices among product line practices. This paper also illustrated a real application case that adopt this approach. The systematic approach enables management attributes, i.e., measurements to be identified when we construct product lines or develop software product based on the product lines. The measurements will be effective in that they are derived in consideration of the application context and interests of stakeholders.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.532-542
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• 2020

Due to abnormal weather conditions such as high temperature, the management of greenhouse rose farms is getting worse. In order to enhance the competitiveness of these farms, new measures are needed to improve their management performance. Therefore, this study suggests alternatives to improve the efficiency and productivity by identifying the causes of inefficiency of greenhouse rose farms in terms of management performance analysis through DEA analysis and MPI analysis. As a result of DEA analysis, the average TE of farmers increased from 0.867('16) to 0.905('17), but decreased to 0.850 in 2018, indicating that it was inefficient. In order to increase the management efficiency of farmers, efforts to preferentially reduce the costs (equipment, employment labor, fertilizer, facilities, seeds) that cause inefficiencies are needed. As a result of MPI analysis, TECI decreased from 1.044(T2) to 0.939(T3), which was the cause of the MPI decrease, and the TCI was rather increased from 0.958(T2) to 0.969(T3). In other words, it means that the decrease in productivity is due to insufficient utilization of potential production technology rather than the slowing of technological progress. This implies that it is important to provide technical guidance on utilization after technology dissemination.

• The Journal of Korean Medicine
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• v.28 no.3 s.71
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• pp.1-12
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• 2007

Objectives : The purpose of this study was to explore the perceptions of health promotion programmes using traditional Korean medicine among public health centre staff in charge of running such programmes. To do so, we examined and analysed the current situation of implementing the programmes in the public health centre. Methods : A survey was designed to collect information on perception of the health promotion programmes using traditional Korean medicine by public health centre staff in charge of running such programmes. The survey, using a structured questionnaire designed for this study, was conducted on 161 public health centre staff attending an annual meeting to presenting the results of activity evaluation related to public health programmes using traditional Korean medicine in public health centres. The participants were asked about the most successful programme, the benefits of the programmes, the positive aspects of the programmes, the most desirable outcomes of the programmes and so on. The data were analysed using SPSS system 12.0 for Windows. Results : Of the 161 questionnaires, 121 were analysed. The main findings of this research were as follows. Of the health promotion programmes using traditional Korean medicine implemented in public health centres, qigong and stroke preventive health promotion programmes were perceived as the most successful. The major benefits of the programmes were having merit for health promotion and expecting a positive performance outcome. The major positive aspects of the programmes for health promotion were cultivating community citizen's support and showing consistency between the philosophy of the programmes and the direction of existing health promotion programmes. The most desirable outcomes of the programmes were spreading community understanding of the programme and establishing an effective and unique health promotion model for implementing the programme. Two major causes of implementation difficulties were lack of material resources such as manpower, facility, and equipment, and methods of performance evaluation. One of the most urgent needs for activating the implementation of programmes was continuing financial and technical support from the central government. Conclusions : To promote the role of traditional Korean medicine in the public health sector in order to integrate traditional medicine into the public health system, government should develop some measures for solving the identified causes of implementation difficulties and coping with the most urgent needs for activating the implementation of programmes.