• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.6
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• pp.2037-2047
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• 1991

Strength is not simply a single given value but rather is a statistical one with certain distribution functions. This is because it is affected by many unknown factors such as size, shape, stress distribution, and combined stresses. In this study, a model of loss probability is proposed in view of the fact that one of the fundamental configuration of nature is hexagonal, for example, the shapes of lattice unit, grain, and so on. The model sues the concept of loss of certain element in place of Jayatilaka-Trustrum's length and angle of cracks. Using this model, the loss probability due to each loss of certain elements is obtained. Then, the maximum principal stress is calculated by the finite element method at the centroid of the elements under the tensile load for the 4,095 models of analysis. Finally, the failure probability of the brittle materials is obtained by multiplying the loss probability by the ratio of the maximum principal stress to theoretical tensile strength. Comparison of the result of the Jayatilaka-Trustrum's model and the proposed model shows that the failure probabilities by the two methods are in good agreement. Further, it is shown that the parametric relationship of semi-crack lengths for various degrees of birittleness can be determined. Therefore, the analysis of the failure probability suing the proposed model is shown to be promising as a new method for the study of the failure probability of birttle materials.

• Science of Emotion and Sensibility
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• v.7 no.4
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• pp.7-17
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• 2004

Recently, design has emerged as a key factor of successful product development. This study reviewed the elements of form with a view point of addressing and defining the elements of aesthetics and how they influence consumer aesthetic response. Though past researches related to form aesthetics reported that form aesthetics exist as a single element with other sub-elements, this research made further investigations into form aesthetics and reported that form aesthetics in product design can be broadly divided into form aesthetics and content aesthetics. Empirical studies on each category was undertaken and from the results obtained, it was concluded that typicality is a dominant element in content aesthetics while balance is a dominant element in form aesthetics. Also, the study investigated the effect of conditional variables such as price and people on each category and it was observed that both content and form aesthetics elements are affected by conditional variables such as price, people. Furthermore, the study reports that both content and form aesthetics elements are mutually correlated and both categories affect user's aesthetics response. It is intended that the results obtained from this work will contribute to theoretical knowledge of aesthetic elements and can be put to use by product design and manufacturing companies.

• Journal of Internet Computing and Services
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• v.17 no.4
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• pp.69-77
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• 2016

Recently, the importance of visual analytics has been recognized in the field of business intelligence. From the view of business intelligence, visual analytics aims for acquiring valuable insights for decision making by interactively visualizing a variety of business information. In this paper, we propose a treemap-based method for visualizing work-sharing relationships among business process performers. A work-sharing relationship is established between two performers who jointly participate in a specific activity of a business process and is an important factor for understanding organizational structures and behaviors in a process-centric organization. To this end, we design and implement a treemap-based visualization tool for representing work-sharing relationships as well as basic hierarchical information in business processes. Finally, we evaluate usefulness of the proposed visualization tool through an operational example using XPDL (XML Process Definition Language) process models.

• Archives of Reconstructive Microsurgery
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• v.11 no.1
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• pp.19-28
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• 2002

From 1994-2001, 25 mutilated digits were reconstructed with immediate toe-to-hand transfer in acute hand injury in 21 patients. There were 15 cases of great toe-to-hand transfer(partial great toe transfer 8 cases, modified wrap-around procedure 2 cases, and trimmed great toe transfer 2 cases) for thumb reconstruction, 2 cases of second toe transfer for index reconstruction, and 4 cases of simultaneous two toe-to-hand transfer(great toe & second toe transfer 1 case, bilateral second-toe transfer 2 cases, combined second & third toe transfer 1 case) for reconstruction of multiple digit amputations. Two cases of emergency exploration(2/25, 8%) were successfully salvaged. The incidence of emergency exploration and postoperative infection was not significantly different from that of the elective toe-to-hand transfer cases. Duration of industrial insurance coverage was 225 days, which is much shorter than that of elective cases. Among 43% of patients maintained their original job even after injury and immediate toe-to-hand transfer. The subjective satisfaction self- assessment scores of aesthetic appearance and function on the new reconstructed thumb were 80 and 88 in average, respectively, over a total score of 100. These were higher than those of reconstruction of other digits, but lower than those of elective reconstruction. The donor site after harvest of the great toe was mostly unsatisfied in a view of appearance. Immediate toe-to-hand transfer provides many advantages over elective procedure in acute hand injuries such as single stage reconstruction, shortened convalescent period, early return to work and efficient socio-economic factor. Furthermore because there were no significant differences in success rate, frequency of complications or ultimate functional result, immediate toe-to-hand transfer is a safe and reliable procedure in case of limited indications for acute digits loss.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2002.06a
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• pp.123-135
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• 2002

Being in era of the digital economy, the influence of IT that effects on our economy is getting greater. Along with this effect, IT becomes origin of predominance of competition in every category of industry. Regarding new trends in industry, how companies mutate their IT skill become important factor. Every industry has their own color and environment of IT and uncertainty is different. For a company, It is most important to plan own strategy with strategic view on industrial environment. The idea of this study is to find the difference of Skill Requirement and Job Requirement in every category of industry by find what are the most important jobs and skills of IT in every industry and to analyze the results. The second idea is to find what kinds of skill are required in every sector of job. Base on the analyzed data, we classified the uncertainty in every industry by Duncan′s "classification of environment", and extracted some pattern within the skill and job in industry that found in our study by applying OIP model. We set skills by categorized curriculum of specialized IT education center, then with IT specialist, checked and retouched the results and surveyed with IT people in every industry on skill set and job of IT. The summery of this study is as follow : 1. Importance of IT skill is differentiated in each industry. It shows that IT skills, which requested in a field are differentiated by uncertainty of environment that comes from the character of industry. 2. Importance of IT job differs by the fields of industry. It shows as IT skills are differentiated, the importance of job that apply these skills is differentiated. 3. As the character of each job that work on is diversified, the importance of skills are diversified in each field of jobs. The Result of this study can give the idea to who designs curriculum and builds educational contentsthat would fulfill the need of fields. Also this study would be meaningful that it opens the field of study of skill requirement in Korea.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.6
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• pp.953-962
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• 1987

Domestic dissimilar structural steels, SM 45 C and SUS304 were friction welded under optimal welding condition and the micro-artificial holes were drilled at SM 45 C base metal, SM 45 C HAZ, welded zone, SUS 304 HAZ, and SUS 304 base metal for fatigue behavior tests. In this study, the fatigue limit and the behavior of micro-crack propagation, crack propagation rate, and its dependency on stress intensity factor under the low stress level and high stress level of bending stress have been investigated. The results obtained are as follows. (1) The fatgiue strength of the portion of SM45C B.M., SM45C HAZ, welded zune, SUS304 HAZ and SUS304 B.M. on notched friction welded specimens are 20 kgf/mm$^{2}$, 32 kgf/mm$^{2}$, 27kgf/mm$^{2}$, 29kgf/mm$^{2}$, and 29kgf/mm$^{2}$, respectively. (2) The fatigue strength of welded zone of unnotched and notched specimens are 32.5kgf/mm$^{2}$, and 27kgf/mm$^{2}$, respectively. (3) Micro-crack initiation in the welded zone, HAZ, and each base metals occurrs simultaneously in front and rear of micro-hole tips in the view of the rotational directions. (4) Fatigue crack propagates more slowly in the welded zone than in another protions of specimen, regardless of the magnitude of the stress level. (5) Fatigue crack propagation rates were plotted as a function of stress intensity range. The value of m in the equation da/dN=C(.DELTA.K)$^{m}$ was found to range from 2.09-2.55 in this study.

• Journal of Korea Multimedia Society
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• v.9 no.8
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• pp.939-949
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• 2006

With the development of industry, product data management system is becoming more and more important. An expanded view of product definition function that include a bill of material and routing database, current and historical engineering data and specifications and engineering changes order history. PDM (Product Data Management) systems hold and manage such material as product specifications, plans, geometric models, CAD drawings and images. Furthermore, PDM enables companies producing complex products to spread product data in to the entire launch process. Especially, PDTnet XML Schema is an international standard for exchanging of PDM data. But PDTnet XML Schema differs from existing XML Schema in the way that its property of IDREF/IDREFS is irregular. Therefore it is important factor that. what do we use storage devices and storage techniques. We developed storage techniques and application supporting various query types and preserving PDTnet XML Schema using a relational database that guaranteeing the performance nowadays. In this paper, we will show that our storage techniques minimize repeated data and optimize query processing by using application comparison with storage techniques of existing XML Schema data.

• Journal of Society of Preventive Korean Medicine
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• v.11 no.1
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• pp.45-53
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• 2007

Homocysteine is a sulfur amino-acid produced during the metabolism of the essential amino acid methionine. Moderately increased plasma total homocysteine concentration have been implicated as a risk factor for occlusive vascular disease. Smoking is known to be one of the most significant factors leading to elevated plasma homocysteine concentration. However, the main component of a cigarette, nicotine has been not studied whether it is linked directly to the increase of homocysteine concentration in blood. The metabolism of homocysteine is closely linked to that of its cofactors, folate. Here, the effects of nicotine and folic acid on amount of plasma homocysteine were studied. The concentration of homocysteine was increased by about 70% in rat plasma after nicotine treatment for one month. This increased concentration of homocysteine was reduced by about 60% at 6 hours later after folate treatment. Thus, nicotine should be directly involved in increasing the concentration of plasma homocysteine. Also it is suggested that these results can be and applied and used for controlling withdrawal symptoms after stopping smoking as one of oriental medicine formulas.

• The Mathematical Education
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• v.50 no.3
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• pp.285-308
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• 2011

The objective of this study is to review how researches on mathematics education are being conducted currently in Korea and overseas and to examine the current state of domestic researches on mathematics education from a broader view. Although many efforts have been made to understand trends in researches on mathematics education, there have been few in depth studies on research trends in overseas or for comparison between domestic and overseas trends. Thus, this study classified and analyzed 181 domestic articles between 2005 and 2009 in the journals and and 201 overseas articles in the journals and according to year, research area, research contents, school level, research method, and key words using the PME classification system with some modification. Through these analysis, we examined research trends on secondary mathematics education in Korea and overseas. The research findings are as follows. First, 'teaching learning process' was a spotlight area both at home and overseas, and 'realistic mathematics' and 'social cultural subjects' were not covered much either at home or overseas. 'Mathematical communication' occupied a very small portion in Korea but was a highly interesting area in overseas research. Second, research contents of interest were different between Korea and overseas. Research on general area was the mainstream. But geometry and statistics were mainly studied in Korea and algebra and analysis in overseas. Third, research related to middle school was twice more than that related to high school in Korea, But, research related to middle school was the same as high school in overseas. Fourth, qualitative research was the absolute majority both at home and overseas, and philosophical didactical analysis was used only in Korea. Fifth, the order of key words were problem solving - teacher - curriculum - creativity - textbook in Korea, but teacher - teaching - semiotic - affective factor - proo f- problem solving - technology in overseas.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.465-468
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• 2003

It has taken a growing interest about environmental problems such as global warming and water pollution. Because of intensified environmental problems, it would be going on the research about environmental preservation and harmful factor reduction. Also, it makes ISO to show the quantitative data about LCA analysis. The research of LCA method in the domestic construction industry has advanced stealing from a national point of view. In this study, it would be possible to confirm the feasibility of a plan by LCA analysis. Moreover, the result of life cycle cost which deliberate the influence cost of environment in the steps of material production, construction, maintenance, and disposal has made to be 74,819,560,776 won in a plan and 78,979.469,602won in alternative. That is, it would analysis for a plan to reduce 4,159,908,826 won for alternative.