• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1995.10a
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• pp.284-288
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• 1995

최근 애매성이 수반되는 정보를 Zadeh는 멤버쉽함수(membership function)를 이용하여 새로운 정보처리 방식으로서 퍼지이론을 제안하였고, 그후 의료계에서도 퍼지이론을 도입한 진단법들이 제안되었다. 회전기계의 이상진단법으로는 주파수득점법(Point counting method), 퍼지역연산법(Inverse method of fuzzy theory)등이 보고되고 있으며, 저자들도 퍼지이론을 이용하여 구름베어링의 결함진단, 회전기계의 간이 이상진단법등을 보고하였다. 이들은 주로 진동주파수의 스펙트럼 데이터 만을 이용하고 있고, 다른 많은 데이터를 복합적으로 이용할 수 없다. 이 때문에 주로 소규모 문제의 간이진단에서는 효과적이나 진단대상이 복잡하고 대규모로 되면 보다 정확한 원인 추정이 곤란하게 된다. 또한 수치데이터만을 취급할 수 있으므로 진동전문가가 진단에 이용하는 각종의 수치화 될 수 없는 데이터(언어적인 정보)가 취급될 수 없다. 따라서 이들의 진단법은 개략적인 진단은 가능하나 상세한 원인까지는 진단할 수 없는 단점이 있다. 회전기계의 이상판단시 참고가 되는 각종 정보로는 주로 진동진폭의 크기, 진폭과 위상의 변화, 진폭의 변화, 진동파형, 진동벡터의 시간변화 등이 있고, 이들은 수치적으로 표현할 수 있는 계량데이터와 판단의 경계가 불명확한 언어정보(범위데이터)로 나눌 수 있다. 후자는 애매성(fuzziness)을 많이 포함하고 있으며, 엄밀히 측정되는 수치데이터에서도 퍼지성을 가지고 있다. 이러한 언어적인 정보의 애매성을 퍼지추론에서는 [수치적 진리치](numeric truth)와 [언어적 진리치](linguistic truth)의 개념으로 표현하게 되었다. 수치적 진리치는 확실함의 척도를 [0,1] 사이의 수치를 이용하여 표현하고 있으며, 이 수치는 소견의 확실도로서 가능성을 표현한 것이다. 예를 들면, 진동진폭 스펙트럼상에 2X 성분이 상당히 크게 나타나 정렬불량의 가능성이 0.7 정도라고 판정하는 것 등은 이러한 수치적진리치를 이용하는 방법이다. 그러나 상기의 수치적 표현만으로는 확실도를 한개의 수치로서 대표하게 하는 것은 진단의 정밀도에 문제가 있을 것으로 생각된다. 따라서 언어적진리치가 도입되어 [상당히 확실], [확실], [약간 확실] 등의 언어적인 표현을 이용하여 애매성을 표현하게 되었다. 본 논문에서는 간이진단 결과로부터 추출된 애매한 진단결과중에서 가장 가능성이 높은 이상원인을 복수로 선정하고, 여러 종류의 수치화할 수 없는 언어적(linguistic)인 정보ㄷㄹ을 if-then 형식의 퍼지추론으로 종합하는 회전기계의 이상진단을 위한 정밀진단 알고리즘을 제안하고 그 유용성을 검토한다.

• The Journal of the Korea Contents Association
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• v.12 no.1
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• pp.430-437
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• 2012

The purpose of this study is to investigate the relations among anger, suicidal ideation and internet addiction in male high school students. In order to get the data by self-report questionnaires, 191 subject were selected from 1th to 30th of April, 2011. The collected data were analyzed using SPSS WIN/17.0. There were significantly positive correlations between suicidal ideation, anger and internet addiction. Internet use hour and anger explained 29.0% of variance for internet addiction. The findings of this study suggest that self-management and interpersonal relationship program should be need to prevent problem of internet addiction.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.12A
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• pp.1974-1984
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• 1999

In this paper, we introduce a highly efficient data structure that effectively captures the multipath phenomenon needed for accurate propagation modeling and fast propagation prediction. The proposed object representation procedure is called 'circular representation (CR)' of microwave masking objects such as buildings, to improve over the conventional vector representation (VR) form in fast ray tracing. The proposed CR encapsulates a building with a circle represented by a center point and radius. In this configuration, the CR essentially functions as the basic building block for higher geometric structures, enhancing the efficiency more than when VR is used alone. The simulation results indicate that the proposed CR scheme reduces the computational load proportionally to the number of potential scattering objects while its hierarchical structure achieves about 50% of computational load reduction in the hierarchical octree structure.

• The KIPS Transactions:PartB
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• v.14B no.4
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• pp.263-272
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• 2007

This paper proposes a skeleton-based hierarchical shape description scheme, called a skeleton tree, for accurate shape-based image retrieval. A skeleton tree represents an object shape as a hierarchical tree where high-level nodes describe parts of coarse trunk regions and low-level nodes describe fine details of boundary regions. Each node refines the shape of its parent node. Most of the noise disturbances are limited to bottom level nodes and the boundary noise is reduced by decreasing weights on the bottom levels. The similarity of two skeleton trees is computed by considering the best match of a skeleton tree to a sub-tree of another skeleton tree. The proposed method uses a hybrid similarity measure by employing both Fourier descriptors and moment invariants in computing the similarity of two skeleton trees. Several experimental results are presented demonstrating the validity of the skeleton tree scheme for the shape description and indexing.

• Cartoon and Animation Studies
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• s.43
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• pp.231-254
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• 2016

The graphic novel is seemed different from comics in two aspects, visual expression and narrative value. However, they are ambiguous standards, so it needs to research each works of graphic novel deeper. Then this paper studied both of visual expression and narrative in Craig Thompson's "Habibi" that has been recognized a fine graphic novel. As the research about how the modes of expression that an American author choose on purpose to represent an arab female are related with narrative, it will get the point of narrative strategy that graphic novel can have potentially. So It studied new modes of expression as focusing on imagination of arab letters and woman growth-narrative by using Gayle Rubin's 'traffic in women' theory, and how it was related with modes of expression in graphic novel. This paper will be helpful for broadening spectrum of expression in graphic novel as comics media having own narrative form and studying graphic narrative potential.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.180-187
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• 2016

This study was performed to identify the relationship between the SNS addiction tendency, self-assertiveness and interpersonal problems in college students. The subjects consisted of 198 students in Korea. The data were collected using a self-report questionnaire from September 10 to 12, 2013. The data were analyzed by frequency, t-test, ANOVA, and Pearson's correlation using SPSS for Windows version 22. The SNS addiction tendency was significantly negatively correlated with self-assertiveness(r=-.148, p<.05) and significantly positively correlated with interpersonal problems (r=.434, p<.001). Self-assertiveness was significantly negatively correlated with interpersonal problems (r=-.459, p<.001). The higher the SNS addiction tendency, the lower the self-assertiveness and the higher the interpersonal problems. The lower the self-assertiveness, the higher the interpersonal problems. Therefore, to decrease the SNS addiction tendency, increase the self-assertiveness and decrease the interpersonal problems, it is necessary to develop and test program.

• Journal of the Institute of Convergence Signal Processing
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• v.11 no.3
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• pp.244-249
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• 2010

The design of error correction code with low complexity has a good attraction for next generation multi-level cell flash memory. Sharing sub-expressions is effective method to reduce complexity and chip size. This paper proposes a new design method of m-bit parallel BCH encoder based on serial linear feedback shift register structure with low complexity using sub-expression. In addition, general algorithm for obtaining the sub-expression is introduced. The sub-expression can be expressed by matrix operation between sub-matrix of generator matrix and sum of two different variables. The number of the sub-expression is restricted by. The obtained sub-expressions can be shared for implementation of different m-parallel BCH encoder. This paper is not focused on solving a problem (delay) induced by numerous fan-out, but complexity reduction, expecially the number of gates.

• Journal of Educational Research in Mathematics
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• v.27 no.2
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• pp.227-247
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• 2017

The purpose of this study is to investigate the differences in the meanings of two $7^{th}$ grade students over 'a' in expressing and interpreting a function of the form of 'y=ax+b(a, b is a constant, $a{\neq}0$)', and to identify causes of the differences. We collected data from a teaching experiment with four $7^{th}$ grade students who participated in 23 teaching episodes. Analysis of the collected data revealed marked differences between student A and student B in expressing and interpreting given situations with linear functions. The differences between the two students and the causes of differences were also analyzed. The results show that the students expressed and interpreted 'a' in the linear function 'y=ax+b', on the basis of their construction of quantities and their quantitative relationships in a given situation involving a constant rate of change.

• Journal of Digital Convergence
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• v.14 no.6
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• pp.519-525
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• 2016

The purpose of the study was to develop achievement criteria of Creativity and Personality in Expressive Activity. For the study, a Delphi survey was conducted with the selected Delphi experts including doctors of sports pedagogic, physical education teachers and doctors of dance studies who have more than 10-year teaching experience in the expressive activity. In this way, the following study result was obtained. First, 27 elements of creativity in the expressive activity were suggested such as originality, sensitivity, trust, courage, moderation. Second, 54 achievement criteria which were drawn up based on the 27 Creativity and Personality-elements. Achievement criteria of creativity and personality was presented in a modular fashion that could be applied in the creation, representation, appreciation which was composed of main content in expressive activity. By using these modules, physical education teachers could plan a lesson by choosing a various factors of creativity and personality, depending on the intended educational goals.

• Journal of Digital Convergence
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• v.15 no.9
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• pp.427-434
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• 2017

The purpose of this study is to analyze the BI elements of expression for four brand's experience spaces in Korea and propose a direction for improvements for such spaces. I started with the theoretical background of nowadays brand marketing and experiential BI elements through literature researches, and then researched the property of spatial expressions to analyze BI elements. Based on this research, I analyzed four domestic brand experience spaces. As a result, brand experience spaces must clearly express the brand image of the company through various contents and situations to effectively communicate and improve BI expressions. Also, they need long-term experience contents for sustained relationships rather than short-term experiences. I expect this study will be a good resource for BI expression research in brand experience spaces. I also believe that this study can guide other studies about BI expression in other fields.