• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.12
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• pp.6125-6132
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• 2013

This study was designed to examine the relationships between rough and tumble play and children's social language use. The subjects were 90 children in a nursery school in N city. The data was analyzed using the Pearson correlation and stepwise regression. The results were as follows. First, there was a significant positive relationship between rough and tumble play, and the children's social language use. Second, the children's social language use' sub valuables had an effect on rough and tumble play. In particular, 'demand of action' has negative effects on the 'pull and push', and 'catch'. Furthermore, 'rejection' has negative effects on 'collapse' and 'rush'. This suggests that a rough and tumble play program can be developed to enhance the children's social language use.

• Journal of Welding and Joining
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• v.33 no.3
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• pp.25-31
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• 2015

Due to environmental regulations (RoHS, WEEE and ELV) of the European Union, electronics and automotive electronics have to eliminate toxic substance from electronic devices and system. Specifically, reliability issue of lead-free solder joint have an increasing demand for the car electronics caused by ELV banning. The authors prepared engine control unit and cabin electronics soldered with Sn-3.0Ag-0.5Cu (SAC305). To compare with the degradation characteristics of solder joint strength, thermal cycling test (TC), power-thermal cycling test (PTC) and series tests were conducted. Series tests were conducted for TC and PTC combined stress test using the same sample in sequence and continuously. TC test was performed at $-40{\sim}125^{\circ}C$ and soak time 10 min for 1000 cycles. PTC test was applied by pulse power and full function conditions during 100 cycles. Combined stress test was tested in accordance with automotive company standard. Solder joint degradation was observed by optical microscopy and environment scanning electron microscopy (ESEM). In addition, to compare with deterioration of bond strength of quad flat package (QFP) and chip components, we have measured lead pull and shear strength. Based on the series test results, consequently, we have validated of series test method for lifetime and reliability of Pb-free solder joint in automotive electronics.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.267-273
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• 2020

Suction anchors are used for floating structures because they have advantages in installation and stability. Recently, the demand for floating structures requiring low allowable displacement has increased. Thus, it is strongly suggested that the displacement of the suction anchor be evaluated. However, conventional studies regarding suction anchors have concentrated on the capacity of the anchor, and research on the displacement of the anchor is limited. In particular, rotation is the primary behavior of a suction anchor subjected to an inclined load, and related information has been insufficient. Therefore, the main objective of this paper is to investigate the rotation behavior of a suction anchor via centrifuge model tests. The experimental parameters are the inclination of the pull-out load, anchor dimensions, and aspect ratio. The rotation values of suction anchors were compared using a series of load-rotation curves. The results show that the inclination of the load has a dominant influence on the rotation behavior of the suction anchor.

• Journal of Digital Convergence
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• v.18 no.2
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• pp.139-149
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• 2020

New platform governments will play a role to pull intelligent information technology to drive new ecological government innovation and sustainable development in which the government and people work together. On this, in order to establish the platform of the platform government, we will look at recent research trends and lay the foundation for future policy directions and research bases. using Text Mining method, and went through Topic modeling for the collected text data and network analysis was conducted. According to the result, based on latent topic, the stronger the connection center, the weaker the relationship. Through this study, we hope that discussions will take place in a variety of ways to improve the understanding of the supply and demand approach of Korea's platform government and implement appropriate change management methods such as service public base and service provision in accordance with the value and potential topics of platform government.

• Geomechanics and Engineering
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• v.10 no.5
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• pp.677-687
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• 2016

Industrialization and urbanization are the two phenomena that are going relentless all over the world. The consequence of this economic success has been a massive increase in waste on one hand and increasing demand for suitable sites for construction on the other. Owing to the surplus raw materials and energy requirement needed for manufacturing synthetic fibers, applications of waste fibers for reinforcing soils evidenced to offer economic and environmental benefits. The main objective of the proposed work is to explore the possibilities of improving the strength of soil using fly ash waste as an admixture and Human Hair Fiber (HHF) as reinforcement such that they can be used for construction of embankments and land reclamation projects. The effect of fiber content on soil - fly ash mixture was observed through a series of laboratory tests such as compaction tests, CBR and unconfined compression tests. From the stress - strain curves, it was observed that the UCC strength for the optimised soil - flyash mixture reinforced with 0.75% human hair fibers is nearly 2.85 times higher than that of the untreated soil. Further, it has been noticed that there is about 7.73 times increase in CBR for the reinforced soil compared to untreated soil. This drastic increase in strength may be due to the fact that HHF offer more pull-out resistance which makes the fibers act like a bridge to prevent further cracking and thereby it improves the toughness which in turn prevent the brittle failure of soil-flyash specimen. Hence, the test results reveal that the inclusion of randomly distributed HHF in soil significantly improves the engineering properties of soil and can be effectively utilized in pavements. SEM analysis explained the change of microstructures and the formation of hydration products that offered increase in strength and it was found to be in accordance with strength tests.

• Journal of Service Research and Studies
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• v.9 no.1
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• pp.73-86
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• 2019

This study discusses the 4th industrial revolution and technology commercialization (TC), identifies success factor (SFs) for TC from the literature review, and empirically tests these factors through questionnaires to executives in the 4th industrial revolution industries. Literature review identifies 11 SFs and they are communication, management support, incentives for TC, common goals, understanding business, awareness of TC, cooperation among partners, government support, concreteness of technology, demand-pull technology, and experience of TC. Questionnaires were administered to CEOs and CIOs in 202 companies in the 4th industrial revolution industries and final response rate was 64.4% (260 out of 404) that is considered to be high. Respondents rate cooperation among partners as the most important, followed by management support, communication, common goals, and incentives for TC. To successfully pursue technology commercialization projects in the 4th industrial revolution industries, the attention should be focused on SFs that are evaluated as very important.

• Journal of Service Research and Studies
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• v.7 no.2
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• pp.91-105
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• 2017

The purposes of this paper is to identify CSFs for technology commercialization in IT industry, and to empirically investigate the impact of CSFs on the success of technology commercialization. Comprehensive literature study identifies eleven factors affecting the process and results of technology transfer and the research results show that 'Incentives for Commercialization,' 'Leadership Support,' 'Government Support,' 'Cooperation among Parties,' and 'Understanding of Business' are the most influential factors. Regression analyses show that CSFs in total have very significant explanatory power in the success of technology commercialization. 'Incentives for Commercialization,' 'Cooperation among Parties, 'Demand-Pull Technology', and 'Commercialization Experience' are statistically significant in explaining the success of commercialization. Successful commercialization projects show higher explanatory power (46.80%) than failure projects (38.50%).

• Journal of the Korean institute of surface engineering
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• v.55 no.2
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• pp.102-119
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• 2022

Gold plating is used as a coating of connecter in printed circuit boards, ceramic integrated circuit packages, semiconductor devices and so on, because the film has excellent electric conductivity, solderability and chemical properties such as durability to acid and other chemicals. As increasing the demand for miniaturization of printed circuit boards and downsizing of electronic devices, several types of electroless gold plating solutions have been developed. Most of these conventional gold plating solutions contain cyanide compounds as a complexing agent. The gold film obtained from such baths usually satisfies the requirements for electronic parts mentioned above. However, cyanide bath is highly toxic and it always has some possibility to cause serious problems in working environment or other administrative aspects. The object of this investigation was to develop a cyanide-free electroless gold plating process that assures the high stability of the solution and gives the excellent solderability of the deposited film. The investigation reported herein is intended to establish plating bath composition and plating conditions for electroless gold plating, with thiomalic acid as a complexing agent. At the same time, we have investigated the solution stability against nickel ion and pull strength of solder ball. Furthermore, by examining the characteristics of the plated Au plating film, the problems of the newly developed electroless Au plating solution were improved and the applicability to various industrial fields was examined. New type electroless gold-plating bath which containing thiomalic acid as a complexing agent showing so good solution stability and film properties as cyanide bath. And this bath shows the excellent stability even if the dissolved nickel ion was added from under coated nickel film, which can be used at the neutral pH range.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.440-447
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• 2020

The demand for large-scale horticultural complexes utilizing reclaimed lands is increasing, and one of the pending issues for the construction of large-scale facilities is to establish foundation design criteria. In this paper, we tried to review previous studies on the method of reinforcing the foundation of soft ground. Target construction methods are spiral piles, wood piles, crushed stone piles and PF (point foundation) method. In order to evaluate the performance according to the basic construction method, pull-out resistance, bearing capacity, and settlement amount were measured. At the same diameter, pull-out resistance increased with increasing penetration depth. Simplified comparison is difficult due to the difference in reinforcement method, diameter, and penetration depth, but it showed high bearing capacity in the order of crushed stone pile, PF method, and wood pile foundation. In the case of wood piles, the increase in uplift resistance was different depending on the slenderness ratio. Wood, crushed stone pile and PF construction methods, which are foundation reinforcement works with a bearing capacity of 105 kN/㎡ to 826 kN/㎡, are considered sufficient methods to be applied to the greenhouse foundation. There was a limitation in grasping the consistent trend of each foundation reinforcement method through existing studies. If these data are supplemented through additional empirical tests, it is judged that a basic design guideline that can satisfy the structure and economic efficiency of the greenhouse can be presented.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.2 no.1
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• pp.132-177
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• 1974

Toe public library may perform a social good only when its objectives are adequate to the community's needs. The present purpose of the public library in the Korean Library Act has no direct concern for our social needs from its very beginning because it was not created in response to our social needs but transplanted from American principles. It is, therefore. difficult to expect socially useful output of our public library programs under the present purpose which may be inadequate to our social tradition and needs. This study purposes to examine validity of the present purpose of the public library in the Korean Library Act, in the light of our community needs and our own library tradition. The methods employed to achieve the purpose of the study are (1) to survey needs of the library frequenters through questionnaire, and interviews with the public librarians in Seoul, (2) to gather the statistical data relevant to, and supporting, the hypothesis, and (3) to compare our social background with that of the United States of which the American purpose, a model for our present purpose, came out. The conclusion is as follows: A. The idea to induce people to pull themselves upward by providing for all the members of the community access to the world's best books shelved in the public library should be abandoned. The reasons are (1) that the idea is alien in our public library tradition, (2) that little demand of the community goes with the idea, and (3) that reading outside the library has come into wide practice, thanks to recent increase in individual income and that in publications. B. That the public library maintains fiction and other recreational reading materials is meaningless in the light of the community needs. These are the two explanations supporting the thesis. (1) The "uplift" theory has proved inoperative and people apparently do not progress from, light fiction to more respectable fare. (2) The conviction that fiction and other recreational reading materials keep the middling classes from the "vicious" entertainments maintaining order in the community by giving them a harmless source of recreation has lost its significance as the modern society provides a number of choices in recreation: television is an obvious example. C. The nature of the informational needs of the community has radically changed, so radically as to require substantial changes in the outlook, collections, and services of the public library, which is :slow in adopting itself to the new social surroundings in Korea. D. 92.2 per Cent of the present frequenters of the public library are high school and college students. Since the library is to meet the existing community needs it should turn its attention to the student group, and develop the means to serve it better, not the "theoretical group of specialists who do not come to "the public library. E. In revision of the purpose of the public library, priority of each objective should be given. The priorities in the last analysis are research and information. culture, recreation in that order.