• International Journal of Railway
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• v.2 no.3
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• pp.124-126
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• 2009

Energy savings can be achieved with optimum energy consumptions, brake energy regeneration, efficient energy storage (onboard, line side), and primarily with light weight vehicles. Over the last few years, the rolling stock industry has experienced a marked increase in eco-awareness and needs for lower life cycle energy consumption costs. For rolling stock vehicle designers and engineers, weight has always been a critical design parameter. It is often specified directly or indirectly as contractual requirements. These requirements are usually expressed in terms of specified axle load limits, braking deceleration levels and/or demands for optimum energy consumptions. The contractual requirements for lower weights are becoming increasingly more stringent. Light weight vehicles with optimized strength to weight ratios are achievable through proven design processes. The primary driving processes consist of: $\bullet$ material selection to best contribute to the intended functionality and performance $\bullet$ design and design optimization to secure the intended functionality and performance $\bullet$ weight control processes to deliver the intended functionality and performance Aluminium has become the material of choice for modern light weight bodyshells. Steel sub-structures and in particular high strength steels are also used where high strength - high elongation characteristics out way the use of aluminium. With the improved characteristics and responses of composites against tire and smoke, small and large composite materials made components are also found in greater quantities in today's railway vehicles. Full scale hybrid composite rolling stock vehicles are being developed and tested. While an "overdesigned" bodyshell may be deemed as acceptable from a structural point of view, it can, in reality, be a weight saving missed opportunity. The conventional pass/fail structural criteria and existing passenger payload definitions promote conservative designs but they do not necessarily imply optimum lightweight designs. The weight to strength design optimization should be a fundamental design driving factor rather than a feeble post design activity. It should be more than a belated attempt to mitigate against contractual weight penalties. The weight control process must be rigorous, responsible, with achievable goals and above all must be integral to the design process. It should not be a mere tabulation of weights for the sole-purpose of predicting the axle loads and wheel balances compliance. The present paper explores and discusses the topics quoted above with a view to strengthen the recommendations and needs for the weight optimization by design approach as a pro-active design activity for the rolling stock industry at large.

• Journal of Korea Water Resources Association
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• v.53 no.11
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• pp.939-949
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• 2020

Currently, the demand for farmland is steadily decreasing due to changes in the agricultural environment and dietary life. In line with this, the government adopted an integrated water management with the enactment of the Framework Act on Water Management on June 2019. Therefore, it is required to take a closer look at agricultural water demand that accounts for 61% of water use for efficient water resources management. In this study, the overal process was evaluated for estimating agricultural water demand. More specifically, agricultural water demand for paddy field, which comprises 67% to 87% of agricultural water demand, was reviewed in detail. The biggest issue in estimating the paddy field water demand is the selection of the method for potential evapotranspiration. FAO recommends Penman-Monteith, but, currently, our criteria suggest a modified Penman equation that shows over estimation. Also, the crop coefficient, which is the main factor in evaluating evapotranspiration, has an issue that does not consider the current climate and crop varieties because it was developed 23 years ago. Comparing the Modified Penman and Penman-Monteith equations using the data from Jeonju National Weather Service, the modified Penman equation showed a big difference compared to the Penman-Monteith equation. When the crop coefficient was applied, the difference between late May and late August increased, where the amount of evapotranspiration was high. The estimation process was applied to four study reservoirs in Gimje. Comparing the estimated water demand with the supplied water record from reservoirs, the results showed that the estimation accuracy depends on not just the potential evapotranspiration, but also the standard water storing level in paddy fields.

• Journal of Korean Home Economics Education Association
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• v.21 no.4
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• pp.145-158
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• 2009

The purpose of this study was to find out how much home economics(HE) textbook was focused on what kind of factors in career education, by analyzing the HE textbooks from the 7th grade(1st grade of the middle school) to the 10th grade(1st grade of high school), which were developed by applying the 7th educational process. 12 textbooks which were published by three publishers were randomly selected by grade. This study used the instrument developed by Korea Research Institute for Vacational Education & Training(2001) as an analysis frame, along with a content analysis system. The results of this study were as follows. The publishers of HE textbook stressed similar points in each section of career education, evenly reflecting the objectives and contents of career education. Three kinds of publishers also placed the same weight on the factors of career education in each unit, and suggested the contents related to career education in the whole units. HE textbook was designed to lead learners to understand self and have interest in varied occupations. Additionally, it provided the learners with a chance to consider their career and occupation by means of detailed job information, and its contents including learning of occupational ability for job selection were useful to plan and prepare for career. Accordingly, as HE textbook is most effective to promote connection between work and learning and contains proper factors of career guidance, it is one of the most appropriate textbooks to deal with career education.

• Korean Journal of Construction Engineering and Management
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• v.14 no.3
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• pp.78-87
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• 2013

The modern society has been drastically changed from the industrial economic society to the knowledge based society, to catch up with the knowledge and the change of technology required for the modern people, the people can not live in the modern society without the continued study or education. In case of architectural design firm, it is concentrating on the productivity of enterprise by cultivating the working level through the self education focused on the improvement of inner capacity. In connection with this, the efficiency of enterprises are analyzed by carrying out the Data Envelopment Analysis(DEA) utilizing the financial ratio index in the various field of industries recently, the analysis study for the efficiency utilizing DEA is increased in the construction industries as well. However, in case of construction industries, the study focused on the efficiency of administration only has been progressed, it is the real situation that the approach for the analysis of education efficiency of each enterprise is very insufficient. Therefore, this study analyzed the education efficiency of architectural design firm after the selection of input and output variables by utilizing the DEA model and utilizing the AHP analysis technique by deducting the variables through the preceding study in relation to the education efficiency and the interview with the specialists.

• Journal of Korean Society of Forest Science
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• v.106 no.1
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• pp.70-76
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• 2017

Among the forest road pavement methods, the majority of current constructions utilize concrete pavements but it has disadvantages as follows: many cracked concrete pavements generated by the erosion of underlying soil layers, could not be used as forest roads in steep slope during winter, and cement contains hazardous chemicals (hexavalent chromium, etc.). In order to supplement the limitations of the use of concrete pavement, this study was conducted to investigate the operation process and cost, the strength and compaction of the experimental forest road pavement(85 m) utilizing eco-friendly solidification material at Goryeong-gun, Gyeongsangbuk-do. The work elements of experimental forest road paving were classified into: preparation, Roadbed excavation, Roadbed grading, subgrade compaction, form work, collection and selection of site soil, mixing site soil and eco-friendly solidification material, paving by eco-friendly solidification material, compaction by vibrating roller and curing. The result of economic analysis using construction cost shows that for concrete costs total to $38,681won/m^3$ while for the eco-friendly paving material it is $38,245won/m^3$. Thus the construction costs for concrete and the eco-friendly paving material are similar. And the results of the Schmidt Hammer test for strength analysis by curing period are 10.5-13.5 MPa for 7 days, 18.1-22.7 MPa for 14 days, and 20.8-23.0 MPa for 28 days.

• Journal of the Microelectronics and Packaging Society
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• v.19 no.2
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• pp.7-15
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• 2012

Semiconductor packages are increasingly moving toward miniaturization, lighter and multi-functions for mobile application, which requires highly integrated multi-stack package. To meet the industrial demand, the package and silicon chip become thinner, and ultra-thin packages will show serious reliability problems such as warpage, crack and other failures. These problems are mainly caused by the mismatch of various package materials and geometric dimensions. In this study we perform the numerical analysis of the warpage deformation and thermal stress of 4-layer stacked FBGA package after EMC molding and reflow process, respectively. After EMC molding and reflow process, the package exhibits the different warpage characteristics due to the temperature-dependent material properties. Key material properties which affect the warpage of package are investigated such as the elastic moduli and CTEs of EMC and PCB. It is found that CTE of EMC material is the dominant factor which controls the warpage. The results of RSM optimization of the material properties demonstrate that warpage can be reduced by $28{\mu}m$. As the silicon die becomes thinner, the maximum stress of each die is increased. In particular, the stress of the top die is substantially increased at the outer edge of the die. This stress concentration will lead to the failure of the package. Therefore, proper selection of package material and structural design are essential for the ultra-thin die packages.

• Journal of Wetlands Research
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• v.17 no.2
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• pp.163-175
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• 2015

In this paper, soil erosion and soil loss management system (SMS) of the City of Calgary in Albert, Canada was reviewed. Regulatory basis supporting this soil management system, permit process and conditions, guidelines and principles for the SMS, and monitoring and repair duties, inspection were discussed. Permit process in the City of Calgary is handled mainly by Urban Development Division, in which special task force called CPAG (Coorporative Planning Application Group) (if necessary circulated through related subdivisions). Inspects all the permit conditions and decides permit or refusal, and LUM (Land Use and Mobility) advertises the approval, if there is no appeals, permit is released to developers. If permit is rejected, applicant can appeals Development Appeal Board, it can approve or reject. In addition to permit, the city has manual for soil management plan, which includes BMP selection, design, monitoring, maintenance, and inspection activities. Perfect SMS policy does not necessarily guarantee relieving the soil-particle related pollution problem, but in Korea, we have to recognize that construction works during development is potentially the most destructive stage of environmental pollution. The central and local governments must make preparations for the effective and tight regulations and ordinance which is appropriate for regional social-economic conditions.

• Korean Journal of Comparative Education
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• v.27 no.1
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• pp.29-49
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• 2017

The purpose of this study is to analyze the characteristics and implications of the quality management policy through teachers' entire life in Japan case study. This article composed of four chapters; Implication and problem situation, Backgrounds and streams of the japanese teacher reform policy, Characteristics of the main policies about managing the teacher's quality through their life, and Conclusion(Japanese characteristics and the suggestion for Korea). The main quality management policy means the various teacher recruitment and selection system, Merit system of personnel management, Effective management of a system for teachers performing unsatisfactorily, Professional development for teachers with new and 10 years' experience, and Teacher Certificate Renewal System every ten years. The method of study composed of the literature search and interview. The System Analysis[input-process-output-feedback] is used as a model of the analyze the policy process[backgrounds & T.O-quality management system-japanese teacher's reaction & implications to korea] The Central Council for Education(CCE;2012.8.28) has released "An Outline of Measures for Comprehensively Improving the Quality and Ability of Teachers throughout their career". This report can be regarded as a blueprint for the teacher reform policy in japan. As a conclusion, Ten lessons is proposed for the Korea policy improving the quality and ability of teachers(training, employment, and development).

• Journal of Digital Convergence
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• v.19 no.12
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• pp.495-504
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• 2021

This review aims to identify the virtual reality (VR)-based home modification programs and provide basic data for the future development and application of domestic VR-based home modification programs. We collected the studies of academic publication or conference, symposium addressed VR-based home modification from January 2011 to June 2021 using hand searching and databases such as Medline, Embase, and Scopus. A total of 7 studies were selected through selection criteria, and the studies were quantitative and qualitative studies on the development of VR prototype for home modification and the acceptability and usability of the programs. VR-based home modification have been developed and applied for various purposes for stakeholders involved in home modification. It can be used as the tools for fostering experts in home modification, evaluating the home environment remotely, and facilitating communication and collaboration with the stakeholders in the modification process. In the future, studies on development and feasibility of VR-based home modification program reflecting the characteristics of domestic housing should be conducted, and it is expected to be utilized as a tool to support the home modification process.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.6
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• pp.27-38
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• 2018

The purpose of this study is to find out common investment decision factors for CVC's invested technology-based startups and analyze them. We examined 17 CVCs that invested in technology startups for three years and six months from 2015 to June 2018. As a result, the final 9 CVCs that can be used in this study were confirmed and 188 companies were analyzed. This study was conducted as a case study to propose and demonstrate CVC investment objectives and investment decision factors analysis model. The results of this study are as follows. First, CVC focused on strengthening investment. Second, In 2015, Invested in an average of 19 months of technology-based startups. In recent years, we invested in 36 months of proven technology-based startups. Thirdly, ICT service was the main business type of the invested startups. Fourth, the investors were concentrated on the stage of Series A~B. It is observed that CVC investment determinants have a significant impact on product or service and parent company relations. In addition, it was found that factors such as innovation, business planning competency, enterprising, strategic competency, leadership, and opportunity recognition competency were influential factors for the startups of invested companies and it was found that these factors are important for CVC investment decision. Understanding of CVC investment determinants presented in this study is based on the establishment of the investment process of the investee, entrepreneurship and management education program. The results of this study can be applied to the selection of excellent startups, entrepreneurship education programs, mentoring, development of coaching guidelines, and establishment of investment process of other investment institutions when investing in CVC.