• Transactions of Materials Processing
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• v.28 no.6
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• pp.321-327
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• 2019

In this study, a hot and cold forging process was investigated to produce a complex-shaped hub of dual clutch transmission with low material loss and high productivity. The process was designed by the commercial finite element (FE) analysis program, DEFORM-2D (hot forging) and 3D (cold forging). And, the material flow and ductile fracture characteristics were studied to check the surface crack initiation of the specimen. The simulation results indicated that the proposed process could manufacture the complex-shaped hub with no surface crack and high-efficiency compared to the conventional machining process. For verification the numerical results, the hub of the SCM440 was fabricated by the proposed process and the mechanical properties and microstructure evolution were studied. It was demonstrated that the suggested hot and cold forging process might be useful in producing the key components of the automobile industry as a high-efficiency and environmentally friendly process.

• Journal of the Society of Naval Architects of Korea
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• v.47 no.3
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• pp.321-327
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• 2010

During sailing by wind-driven thrust on the sail, a catamaran sailing yacht generates leeway and heeling. For estimating resistance and moment prediction of a real ship by changing of running attitude, a model test of the ship has to be carried out. This study aims at establishing experimental techniques for a catamaran sailing yacht by changed attitude during running direction. Through the model test, drag and side force of the real ship are predicted. Also through experiment, rolling and yawing moments were considered.

• Journal of Navigation and Port Research
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• v.37 no.3
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• pp.321-327
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• 2013

As the market of express delivery services expands rapidly, delivery service companies are exposed to severe competition. As a result of the surplus of delivery companies, they are struggling with remaining competitive at a reasonable price with appropriate level of customer satisfaction. To cope with competition pressures, a strategic alliance is suggested as an effective solution to the challenges faced by small and medium enterprises (SMEs) in express delivery services. Therefore, this study suggests a combined optimization and simulation approach to the reconfiguration of an express delivery service network for strategic alliance with respect to strategy partnership of closing/keeping service centers among companies involved and adjustments of their cutoff times. An illustrative numerical example is presented to demonstrate the practicality and efficiency of the approach.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.4
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• pp.321-327
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• 2012

This paper presents a comparative analysis on three different types of performance indices of obstacle detection for an overlapped ultrasonic sensor ring. Due to beam overlap, the entire sensing zone of each ultrasonic sensor can be divided into three smaller sensing subzones, which leads to significant reduction of positional uncertainty in obstacle detection. First, the positional uncertainty in obstacle detection is expressed in terms of the area of a sensing subzone, and type 1 performance index is then defined as the area ratio of side and center sensing subzones. Second, based on the area of a sensing subzone, type 2 performance index is defined taking into account the size of the entire range of obstacle detection as well as the degree of the positional uncertainty in obstacle detection. Third, the positional uncertainty in obstacle detection is now expressed in terms of the length of the uncertainty arc spanning a sensing subzone, and type 3 performance index is then defined as the average value of the uncertainty arc lengths over the entire range of obstacle detection. Fourth, using a commercial low directivity ultrasonic sensor, the changes of three different performance indices depending on the parameter of an overlapped ultrasonic sensor ring are examined and compared.

• Earthquakes and Structures
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• v.18 no.3
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• pp.321-335
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• 2020

The aim of the present contribution is to consider and underline the essential interactions among the historical knowledge, the seismic vulnerability assessment, the investigation experimental tools, the preservation of the architectural quality and the strengthening design in regard to architectural heritage conservation. These topics are argued in relation to Palazzo Murena in Perugia, designed in the eighteenth century by the famous Architect Luigi Vanvitelli, and currently headquarters of the city's University. Based on the surveys and the visual inspections, a preliminary a priori global analysis has been performed by means of the FME method. The obtained results permitted to plan an experimental tests campaign inclusive of structural health monitoring. The new achieved "knowledge" of the building allowed to refine the seismic safety assessment. In particular it was highlighted that the "mezzanine floor" can be a vulnerable element of the building with the collapse of its masonry walls. Preserving the architectural characteristics, a local reinforcement intervention is proposed for the above-mentioned level; this consists of the application of plaster with FRCM, assuring an adequate strength, without burden the masonry structure with additional weight, and therefore a decreasing of the seismic vulnerability. The necessity to consider, in this ongoing research, other local mechanisms is highlighted in the unfolding of the last part of work.

• Wind and Structures
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• v.31 no.4
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• pp.321-334
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• 2020

Engineering type tropical cyclone (TC) wind field models are used to estimate TC wind hazard. Some of the models are well-calibrated using observation data, while others are not extensively compared and verified. They are all proxies to the real TC wind fields. The computational effort for their use differs. In the present study, a comparison of the predicted wind fields is presented by considering three commonly used models: the gradient wind field model, slab-resolving model, and a linear height-resolving model. These models essentially predict the horizontal wind speed at a different height. The gradient wind field model and linear height-resolving model are simple to use while the nonlinear slab-resolving model is more compute-intensive. A set of factors is estimated and recommended such that the estimated TC wind hazard by using these models becomes more consistent. The use of the models, including the developed set of factors, for estimating TC wind hazard over-water and over-land is presented by considering the historical tracks for a few sites. It is shown that the annual maximum TC wind speed can be adequately modelled by the generalized extreme value distribution.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.5
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• pp.321-328
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• 2016

Cranes are generally used to drop or lift equipment or materials. The present study focuses on equipment used for dropping and lifting the sonar system for undersea exploration. This study deals with a GA-based MATLAB$^{(R)}$ simulation for the design optimization of a new overboarding prototype with a two degree-of-freedom mechanism, including a parallelogram link, which is efficient in sonar system operation and maintenance. First, the strengths and weaknesses of the existing overboarding mechanisms are analyzed. The new mechanism to solve these problems is then suggested. For the proposed mechanism, the GA-based MATLAB$^{(R)}$ simulation technique is applied to the proposed mechanism to optimize the link lengths and the actuator lengths. By doing this, the mechanism cannot interfere in the hull's internal environment. Hence, the work range of motion (ROM) is satisfied, and good torque-angle properties are obtaind. The developed technology will be helpful in calculating the maximized output torque of the actuator for the application in practice using a similar type of the proposed mechanism.

• Journal of the Korean Society for Library and Information Science
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• v.39 no.2
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• pp.321-346
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• 2005

This research is a case study with the subject of 5th grade elementary students, practice a developmental bibliotherapy, and check the influence on the self-actualization. The subjects of this research is 20 students of 5th grade C elementary school in Gyeonggi Province, (including experimental group.10 students, control group: 10 students) and we practiced 12 times for 6 weeks. The result of the experimental group represents meaningful effects in the scales of inner-directed, self-actualization value, feeling reactivity, spontaneity, self-regard, self-acceptance. Then, we found in the lasting scale that the effect was lasting after 3 weeks. Therefore, we conclude that a developmental bibliotherapy can gives elementary students a positive influence, and help them form their proper notion as human being.

• Proceedings of the Korea Information Processing Society Conference
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• 2018.10a
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• pp.321-322
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• 2018

본 연구에서는 학습자의 프로그래밍 학습능력을 향상시키기 위하여, 학습효과에 영향을 미치는 교수 전략을 규명하는 것을 목표로 하였다. 프로그래밍 학습효과에 영향을 미치는 교수전략으로는 진도 적절성, 난이도 적절성, 교수자의 개입수준, 유머 사용으로 측정하였으며 학습효과는 성취도와 만족도를 측정하였다. A 전문대학의 컴퓨터공학과 110명의 학생을 대상의 설문을 실시한 후 학습효과에 대한 교수전략의 영향을 분석한 결과, 난이도 적절성이 성취도에 영향을 끼치며, 난이도 적절성과 교수자의 개입수준이 수업만족도에 영향을 미치는 것으로 규명되었다. 이에 따라 프로그래밍의 학습효과를 향상시킬 수 있는 시사점을 제안하였다.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.1
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• pp.321-328
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• 2019

The purpose of the study is to analyze the main approaches to assessing human capital and develop proposals for its most objective assessment of it at the different levels of manifestation - individual, microeconomic and macroeconomic. The article considers the basic approaches to the evaluation of human capital, used in practice: retrospective (costly) and prospective (income based). Cost based methods involve measuring the value of human capital based on the total costs associated with its formation. The proposed additional evaluation criteria, in particular, the use of the expert approach and the developed indicators of a qualitative assessment of the human capital of the enterprise will allow development that is more efficient and use of available human resources. Human capital is becoming a major factor in the formation and development of an innovative economy and knowledge economy. Accordingly, the proposed additions to the assessment of human capital at the country level are aimed at assessing it from a new angle, taking into account the current global trends in the formation of an innovative economy and digitalization. They meet qualitatively new requirements for human capital as the main productive factor in the creation of new highly efficient technologies that promote the active development of the social sphere, science, education, health, etc.