• Journal of Korean Institute of Industrial Engineers
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• v.36 no.2
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• pp.108-116
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• 2010

The maintenance of a deteriorating system is often imperfect. Previous studies have shown that the imperfect preventive maintenance (PM) can reduce the wear out and aging effects of deteriorating systems to a certain level between the conditions of as good as new and as bad as old. In this paper, we employ the concept of the improvement factor in investigating two optimal PM policies; failure limit policy and periodic PM policy. We redefine the improvement factor model as a function of the cost of PM, using this concept, we derive the conditions of optimal PM policies and formulate expressions to compute the expected cost rate. Based on this information, the determination of the maintenance policies which minimize the cost rate is examined. Numerical examples for the Weibull distribution case are also given.

• Corrosion Science and Technology
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• v.3 no.4
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• pp.161-165
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• 2004

Aluminum source in an Al-Fe coating reacts with molten carbonate and develops a protective $LiAlO_2$ layer on the coating surface during operation of molten carbonate fuel cells (MCFC). However, if aluminum content in an Al-Fe coating decreases to a critical level for some reasons during MCFC operation, a stable and continuous $LiAlO_2$ protective layer can no longer be maintained. The aluminum content in an Al-Fe coating can be depleted by two different processes; one is by corrosion reaction at the surface between the aluminum source in the coating and molten carbonate, and the other is inward-diffusion of aluminum atoms within the coating into a substrate. In these two respects, therefore, the decreasing rate of aluminum concentration in an Al-Fe coating was measured, and then the influences of these two aspects on the lifetime of Al-Fe coating were investigated, respectively.

• Journal of Korea Technology Innovation Society
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• v.14 no.4
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• pp.937-964
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• 2011

The research question of this work comes from that there have been disputes for the governance and roles of the Rural Development Agency (RDA), despite of rather excellence performances of Agricultural R&D program supported by RDA. For this reason, I meta-evaluated the internal evaluation system of Agricultural R&D program in RDA, in terms of the four meta-evaluation components such as evaluation paradigm, evaluation resources, evaluation execution and evaluation utilization. The result shows that the most serious problem is rather lower level of evaluation. Object, one of the evaluation paradigms in the R&D evaluation system of the RDA. So, this work suggested the policy alternatives which may lead the R&D evaluation system of the RDA to be developed for the performance-oriented R&D management system.

• Proceedings of the Technology Innovation Conference
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• 1999.12a
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• pp.216-239
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• 1999

Korean government has planned a large scale multidepartment-participated national R&D program to advance and improve her science and technology and the quality of life In the level of advanced(especially G-7) countries in the forthcoming 21st century. It is called as "Highly Advanced National projects" or "G7 projects", which was initiated in 1991 with 18 sub-programs to date. It has planned to be continued until 2001 with its total fund of 4, 591 billion Won, comprised of 2, 033 billion Won from the public sector and 2, 558 billion Won from the private sector. Evaluation activities, the country has carried out to date, for national R&D programs including HAN projects are focused mainly on the assessment of scientific and technological results to decide that a specific program should be continued, terminated, or modified. Thus, it is necessary for national R&D programs to be evaluated socioeconomically for the purpose of assessing the nationwide economic and social impact from the program. Socioeconomic evaluation would be told how and where the program contributed to the society, and what the socioeconomic impacts are resulted from the program. It would be useful for the means of (ⅰ) fulfillment of public accountability to legitimate the program and to reveal the expenditure of pubic fund, and (ⅱ) managemental and strategical learning to give information necessary to improve the making. program and policy decision making, The objectives of the study are to develop the methodology of modeling the socioeconomic evaluation, and build up the practical socioeconomic evaluation model of the HAN projects including scientific and technological effects. Since the HAN projects consists of 18 subprograms, it is difficult In evaluate all the subprograms simultaneously. Despite, each program is being performed under the category of HAN projects, so the common socioeconomic issues are existing, The followings are main results of the study. First, the hierarchical structure of the socioeconomic evaluation are constructed; Evaluation Perspective, Evaluation Bounds, and Evaluation Aspect. Second, based on the goals of the HAN projects, the evaluation perspectives are established as (ⅰ) the strengthening of industrial competitiveness, (ⅱ) the enhancement of national scientific and technological capability, (ⅲ) the improvement of quality of life. Third, the evaluation bounds for each evaluation objective are defined to specify the affected area. Finally, the evaluation aspects for each evaluation bounds are formulated containing essential elements describing the evaluation bounds.

• Journal of Information Technology Services
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• v.19 no.1
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• pp.173-185
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• 2020

It is very important to evaluate training because it can systematically grasp the current status of training. Evaluation includes getting ongoing feedback from the learner, trainer and learner's supervisor, to improve the quality of the training and identify if the learner achieved the goals of the training. It also provides a justification for the implementation of training. Nonetheless, there is a lack of studies that attempt to evaluate information security training programs. In this study, we utilize the Philips model to evaluate the public training programs for the people who are in charge of the information security duties in the public sector and propose the training improvement plans. Research result has shown that it is necessary to evaluate the level of the trainees in advance and conduct training programs according to the information security skill level. In addition, it needs to conduct training according to duties such as information security management, information security operate and maintain. The limitation of this study is that each education program was not assessed individually because this study had developed an evaluation tool that could be used comprehensively.

• Journal of Auto-vehicle Safety Association
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• v.12 no.3
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• pp.43-51
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• 2020

Currently, the second level of the six stages of self-driving technology, as defined by SAE, is commercialized, and the third level is preparing for commercialization. The purpose of ACC is to be evaluated as a system useful for preventing and preventing accidents by minimizing driver fatigue through longitudinal speed control and relative distance control of the vehicle. In this regard, for the study of safety assessment methods in the practical environment of ACC. Distance measurement method using monocular camera and data acquisition equipment such as DGPS are utilized. Based on the evaluation scenario considering the domestic road environment proposed by the preceding study, the relative distance obtained from equipment such as DPGS and the relative distance using a monocular camera in the actual test is verified by comparing and analyzing the safety assessment. The comparison by scenario results showed a minimum error rate of 3.83% in Scenario 1 and a maximum of 14.61% in Scenario 6. The cause of the maximum error is that the lane recognition is not accurate in the camera image and irregular operation conditions such as rushing in or exiting the surrounding area from the walkway. It is expected that safety evaluation using a monocular camera will be possible for other ADAS systems in the future.

• Computers and Concrete
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• v.24 no.6
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• pp.541-553
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• 2019

Alkali-silica reaction (ASR) in concrete can induce degradation in its mechanical properties, leading to compromised serviceability and even loss in load capacity of concrete structures. Compared to other properties, ASR often affects the modulus of elasticity more significantly. Several empirical models have thus been established to estimate elastic modulus reduction based on the ASR expansion only for condition assessment and capacity evaluation of the distressed structures. However, it has been observed from experimental studies in the literature that for any given level of ASR expansion, there are significant variations on the measured modulus of elasticity. In fact, many other factors, such as cement content, reactive aggregate type, exposure condition, additional alkali and concrete strength, have been commonly known in contribution to changes of concrete elastic modulus due to ASR. In this study, an artificial intelligent model using artificial neural network (ANN) is proposed for the first time to provide an innovative approach for evaluation of the elastic modulus of ASR-affected concrete, which is able to take into account contribution of several influence factors. By intelligently fusing multiple information, the proposed ANN model can provide an accurate estimation of the modulus of elasticity, which shows a significant improvement from empirical based models used in current practice. The results also indicate that expansion due to ASR is not the only factor contributing to the stiffness change, and various factors have to be included during the evaluation.

• Analytical Science and Technology
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• v.18 no.6
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• pp.552-558
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• 2005

A type of dimethyl sulfide gas CRM in the ppb level was developed for the analysis of trace-level odorous gas in environmental atmosphere. The concentration of dimethyl sulfide ($(CH_3)_2S$) was 10 umol/mol level in the cylinder filled with nitrogen, 1500 psi. And the variability of the concentration for 3 years was about 0.1% due to the adsorption or instability of $(CH_3)_2S$. The gas standards produced simultaneously in 4 bottles and examined by GC-FID were shown with 0.4%, reproducibility of preparation and 0.25%, standard uncertainty due to weighing and purity. The relative expended uncertainty of 1.1% (95% of confidence level, k=2) was assigned to the certified value of 10 umol/mol level of $(CH_3)_2S$ after quantitative evaluation on the purity, mixing, weighing, analysis, adsorption and stability of dimethyl sulfide gas.

• IE interfaces
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• v.15 no.4
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• pp.444-451
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• 2002

Recently, the interest in technology valuation is revived and increasing mainly due to the lack of suitability of the traditional valuation methods in explaining the market reaction to newly-emerging knowledge-oriented companies. Moreover, many firms are now gearing their efforts to the strategic use of technology asset such as technology licensing, transfer and commercialization. Firms are also trying to enhance their technological competitiveness by re-evaluating their technology level and thus identifying the strengths/weaknesses of their technology portfolio. To accomplish this objective, the development of an integrated evaluation system for technology assets is essential. This paper presents a technology valuation system developed for a steel manufacturing company in South Korea. The valuation framework is based on; (1) the multi-attribute evaluation of technological competitiveness using Analytic Hierarchical Process and; (2) the expected future benefit of the technology using four different methods of discounted cash flow estimation. The suggested framework will be easily applicable to various industries where technological competitiveness should be evaluated systematically.

• Journal of Information Technology Services
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• v.20 no.2
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• pp.1-11
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• 2021

As a key of access to public participation and information, e-government is taking the active role of public service by relevant laws and policy measures for universal use of e-government websites. To improve the accessibility of web contents, the level of deriving the results for each detailed evaluation item according to the Korean web contents accessibility guideline is carried out, which is an important factor according to the detailed evaluation items for each website property and requires data-based management. In this paper, detailed indicators are analyzed based on the quality control level diagnosis results of existing domestic e-government websites, and the results are classified according to high and low to propose new improvement directions and induce detailed improvement. Depending on the necessity of management according to the detailed indicators for each website attribute, not only results but also level diagnosis to strengthen web service quality suggests directions for future improvement through accurate detailed analysis and research for policy feedback. This study ultimately makes it possible to expect government system management based on predicted data through deduction history management based on evaluation score data on public websites. And it provides several theoretical and practical implications through correlation and synergy. The characteristics of each score for the quality management of public sector websites were identified, and the accuracy of evaluation, the possibility of sophisticated analysis, such as analysis of characteristics of each institution, were expanded. With creating an environment for improving the quality of public websites and it is expected that the possibility of evaluation accuracy and elaborate analysis can be expanded in the e-government performance and the post-introduction stage of government website service.