• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2010년도 춘계 학술논문 발표대회 1부
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• pp.25-27
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• 2010

Helical steel piles are being widely used in foundation for the buildings in urban areas because of their high compressive and tensile capacities. Helical steel piles have many advantages; ease installation, a vibration-free and low level of noise process, and so on. However, the most researches are about the capacity of helical steel piles under uplift condition. Therefore, this paper focuses on the capacity under compressive loading according to the soil condition. The bearing capacity of helical steel piles varies with the diameter of the helix and shaft and the bearing area of helical steel piles is not always identical with the sum of helix and shaft area due to the difference of each bearing mechanism. Therefore, the experiment with the parameters of the ratio of helix and shaft diameter and soil condition will be carried out to survey the effective helix area under a given soil condition for the bearing capacity of helical steel piles.

• 설비공학논문집
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• 제13권1호
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• pp.18-24
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• 2001

Woven wire wick is very effective structure because of its easiness to insert inside of pipe for a miniature heat pipe. The present study was conducted to investigate the effect of the effective flow passage with respect to wire helix angle. Also effective thermal conductivity were examined by defining mean porosity considering effective liquid flow passages. Effective heat transfer area is varied with respect to wire helix angle, and in the range of $\thet=60~65^{\circ}C$, heat transfer area is decreased about 15~20%. Permeability of woven wire wick shows similar value of 200 mesh screen wick. And comparison of experimental results on effective thermal conductivity shows a fairly good agreement with the analytical results.

• 한국공작기계학회논문집
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• 제15권2호
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• pp.73-80
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• 2006

This paper describes a analysis on the chip thickness model required for cutting force simulation in ball-end milling. In milling, cutting forces are obtained by multiplying chip area to specific cutting forces in each cutting instance. Specific cutting forces are one of the important factors for cutting force predication and have unique value according to workpiece materials. Chip area in two dimensional cutting is simply calculated using depth of cut and feed, but not simply obtained in three dimensional cutting such as milling due to complex cutting mechanics. In ball-end milling, machining is almost performed in the ball part of the cutter and tool radius is varied along contact point of the cutter and workpiece. In result, the cutting speed and the effective helix angle are changed according to length from the tool tip. In this study, for chip thickness model analysis, tool and chip geometry are analyzed and then the definition of chip thickness and estimation method are described. The resulted of analysis are verified by compared with geometrical simulation and other research. The proposed chip thickness model is more precise.

• International Journal of Computer Science & Network Security
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• 제21권7호
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• pp.125-132
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• 2021

Rapid growth of the higher education role in ensuring the socio-economic and innovative development of the national economy in the context of the development of the information society and the knowledge economy is observed. Achieving positive synergistic effects of the higher education development requires proper funding for university education and research. The existing funding models for national higher education systems in a number of developing countries need modernization in accordance with the modern challenges of economic and innovative development. The purpose of the article is to formulate theoretical - methodological and applied foundations for the development and implementation of the integrated model of the higher education financing under the Quadruple Helix concept. At the center of the developed model are the areas of interaction identified by the authors, namely: Personnel, Science, Management, Innovation, Social area. This made it possible to specify the interests of all stakeholders and orient the activities of higher education institutions to the satisfaction of these interests. Effective implementation of the integrated Model of the higher education financing requires increasing the level of investment attractiveness and practical value of university research; activation of innovative development of enterprises; state stimulation of business participation in university research and education; harmonization of current legislation with EU standards. Implementation of the Model will diversify sources of funding for universities, increase their level of economic security and achieve integrated synergies from the interaction of universities, business, government and the public (as the main stakeholders within the Quadruple Helix concept).

• Journal of Contemporary Eastern Asia
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• 제14권2호
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• pp.69-79
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• 2015

Among public organizations, does variation in organizational structure explain variation in public managers' leadership styles (e.g., transformational and transactional leadership)? The study of leadership in public organizations is increasingly an area of scholarly interest partly sparked by movements to reform public organizations, particularly in the context of emergency management. There is, for example, a need for effective leadership that can help organizations respond to disasters (Kapucu et al. 2010; Van Wart and Kapucu 2011; Stern 2013). There are numerous documented cases where the lack of leadership skills has been linked to major social and economic losses as a result of poor disaster response (e.g., Hurricane Katrina in the U.S.). Yet, leadership is a complex concept and numerous theoretical frameworks have been developed to help explain it (Van Wart 2005). Practically speaking, the existence of different theories of leadership suggests that public managers can decide to exercise various styles of leadership. The style of leadership that a public manager exhibits matters because some styles are perceived to be more effective than others (Trottier et al. 2008). While the effects of leadership have been extensively studied, antecedents or predictors of leadership style have received little scholarly attention (Wright and Pandey 2009; Nielsen and Cleal 2011). The purpose of this research note then is to explore the potential causal relationship between the structure of an organization and the ability of a public manager to exercise transformational leadership in the context of emergency management in two Asian countries: South Korea and Japan. This research note consists of three main sections. The following section explores the relationship between leadership and organizational structure. The second section examines how certain concepts of leadership and organizational structure were applied in two case studies of disaster response. The final section presents some directions for future research.

• Journal of Contemporary Eastern Asia
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• 제18권1호
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• pp.7-29
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• 2019

This study describes an approach for comparative bibliometric analysis of scientific publications related to (i) individual or several departments comprising a university, and (ii) broader integrated subject areas using multiple disciplinary schemes. It uses a custom dataset of scientific publications (ca. 15,000 articles and reviews, published during 2009-2013, and recorded in the Web of Science Core Collections) with author affiliations to the research departments, dedicated to science, technology, engineering, mathematics, and medicine (STEMM), of a comprehensive university. The dataset was subjected, at first, to the department level and discipline level analyses using the newly available KAKEN-L3 classification (based on MEXT/JSPS Grants-in-Aid system), hierarchical clustering, correspondence analysis to decipher the major departmental and disciplinary clusters, and visualization of the department-discipline relationships using two-dimensional stacked bar diagrams. The next step involved the creation of subsets covering integrated subject areas and a comparative analysis of departmental contributions to a specific area (medical, health and life science) using several disciplinary schemes: Essential Science Indicators (ESI) 22 research fields, SCOPUS 27 subject areas, OECD Frascati 38 subordinate research fields, and KAKEN-L3 66 subject categories. To illustrate the effective use of the science mapping techniques, the same subset for medical, health and life science area was subjected to network analyses for co-occurrences of keywords, bibliographic coupling of the publication sources, and co-citation of sources in the reference lists. The science mapping approach demonstrates the ways to extract information on the prolific research themes, the most frequently used journals for publishing research findings, and the knowledge base underlying the research activities covered by the publications concerned.