• Journal of KIISE:Software and Applications
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• v.26 no.11
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• pp.1306-1313
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• 1999

본 연구는 인터넷 기반 공유가상공간에서 시스템의 확장성을 유지하기 위하여 이동객체를 대상으로 하는 이벤트 필터링 기법을 제안하고자 한다. 제안된 다중격자 모델 기법은 이동객체의 경로 상에서 대표적인 이벤트를 샘플링하는 방식을 사용한다. 이 방식은 메시지 트래픽의 양을 동적으로 조절하기 위하여 이동객체 간의 관심정도 정보를 수치적으로 변환하여 이벤트 갱신빈도에 반영한다. 대량의 이동객체를 생성하여 제안된 기법을 적용한 성능평가 실험에서 기존의 방식에 비하여 평균 메시지 전송량이 50%이상 감소하는 것으로 확인할 수 있었다. 다중격자 모델은 참여자의 수와 메시지 트래픽 상황에 따라 가상환경의 공유 QoS를 동적으로 조절할 수 있으며, 인터넷 상에서 다수 사용자를 위한 3차원 가상사회 구축 및 온라인 네트워크 게임 개발 등에 활용될 수 있을 것이다.Abstract This paper proposes an event filtering technique that can dynamically control a large amount of event messages produced by moving objects like avatars or autonomous objects in a distributed virtual environment. The proposed multi-level grid model technique uses the method that extracts the representative events from the paths of moving objects. For dynamic control of message traffics, this technique digitizes the DOIs of the avatars and reflects the interest information controlling the frequency of message transmission. For the performance evaluation, a large number of moving objects were created and the model was applied to these avatar groups. In the experiments, more than 50% of messages have been reduced in comparison with the existing AOI-based filtering techniques. The proposed technique can dynamically control the QoS in proportion to the number of users and the amount of messages where a large number of users share a virtual space. This model can be applied to the development of 3D collaborative virtual societies and multi-user online games in the Internet.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.12 no.1
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• pp.30-37
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• 2005

Purpose: This study was a descriptive research to investigate the health behavior, health status and self-efficacy according to the concepts of Sasangin. Method: Participants in this study were 214 nurses in hospitals in Seoul, Kyunggi and B city. Data were collected using interview with questionnaires from Oct.2 to Nov.30, 2003. The measurement tools were the QSCC II by Kim et al., Health Behavior by Kim, CMI by Nam and self-efficacy by Sherer, all of which have resported reliability. For the purpose of the study, the collected data were analyzed by Frequency, ANOVA, and Pearson correlation coefficients. Results: 1) There was a significant difference in health behavior according to constitution (F=1 273, p=.020). 2) There was a negative correlation between health behavior and health status for Taeumin (r=-.376, p=.002). There was also a negative correlation between health status and self-efficacy for Taeumin (r=-.271, p=.029). Conclusion: The results of this study showed that there were significant differences in health behavior, health status and self-efficacy for the participants according to the constitution of each nurse. So, based on these results, determining and fully understanding the client's constitution are important as these are the foundations of Eum-Yang and personal characteristics. Therefore, we have to consider the constitution when we provide nursing care. However, this study did not show a correlation between health behavior, health status and self efficacy for Soyangin and Soeumin. Further research is needed to determine if there is a relation between these variables according to various constitutions.

• Steel and Composite Structures
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• v.29 no.4
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• pp.527-544
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• 2018

The paper presents the study on a change in modal parameters and structural stiffness of cable-stayed Fiberline Bridge made entirely of Glass Fiber Reinforced Polymer (GFRP) composite used for 20 years in the fjord area of Kolding, Denmark. Due to this specific location the bridge structure was subjected to natural aging in harsh environmental conditions. The flexural properties of the pultruded GFRP profiles acquired from the analyzed footbridge in 1997 and 2012 were determined through three-point bending tests. It was found that the Young's modulus increased by approximately 9%. Moreover, the influence of the temperature on the storage and loss modulus of GFRP material acquired from the Fiberline Bridge was studied by the dynamic mechanical analysis. The good thermal stability in potential real temperatures was found. The natural vibration frequencies and mode shapes of the bridge for its original state were evaluated through the application of the Finite Element (FE) method. The initial FE model was created using the real geometrical and material data obtained from both the design data and flexural test results performed in 1997 for the intact composite GFRP material. Full scale experimental investigations of the free-decay response under human jumping for the experimental state were carried out applying accelerometers. Seven natural frequencies, corresponding mode shapes and damping ratios were identified. The numerical and experimental results were compared. Based on the difference in the fundamental natural frequency it was again confirmed that the structural stiffness of the bridge increased by about 9% after 20 years of service life. Data collected from this study were used to validate the assumed FE model. It can be concluded that the updated FE model accurately reproduces the dynamic behavior of the bridge and can be used as a proper baseline model for the long-term monitoring to evaluate the overall structural response under service loads. The obtained results provided a relevant data for the structural health monitoring of all-GFRP bridge.

• Korean Journal of Remote Sensing
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• v.24 no.6
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• pp.571-581
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• 2008

The sea fog occurs frequently in the west coast of Korea in spring and summer. This study focused on the detection of sea fog using MODIS satellite images. We presented a method for sea fog detection based on the homogeneity level between low stratus and sea fog, which was that the top surface of sea fog had a homogeneous aspect while that of low stratus had a heterogenous aspect. The results showed that the both homogeneity of $11{\mu}m$ brightness temperature (BT) and brightness temperature difference (BTD, $BT_{3.7{\mu}m}-BT_{11{\mu}m}$) were available to discriminate sea fog from low stratus. The frequency of difference between BT in fog/stratus area and BT in clear area provided reasonable result. In addition, the threshold values of standard deviations of BT and BTD in the fog/stratus area were applicable to differentiate fog from low stratus.

• Journal of Broadcast Engineering
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• v.24 no.5
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• pp.791-801
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• 2019

The serial arc is one of factors causing electrical fires. Over past decades, various researches have been carried out to detect arc occurrences. Even though frequency analysis, wavelet and statistical features have been used, arc detection performance is degraded due to diverse arc waveforms. Therefore, there is a need to develop a method that could increase the feature dimension, thereby improving the detection performance. In this paper, we use variational mode decomposition (VMD) to obtain multiple decomposed signals and then extract statistical features from them. The features from VMD outperform those from no-VMD in terms of detection performance. Further, artificial neural network is employed as an arc classifier. Experiments validated that the use of VMD improves the classification accuracy by up to 4 percent, based on 14,000 training data.

• Coupled systems mechanics
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• v.4 no.4
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• pp.279-295
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• 2015

The article presents a theoretical-experimental approach developed for modeling the coefficient of sliding friction in the dynamic system tool-workpiece in slide diamond burnishing of low-alloy unhardened steels. The experimental setup, implemented on conventional lathe, includes a specially designed device, with a straight cantilever beam as body. The beam is simultaneously loaded by bending (from transverse slide friction force) and compression (from longitudinal burnishing force), which is a reason for geometrical nonlinearity. A method, based on the idea of separation of the variables (time and metric) before establishing the differential equation of motion, has been applied for dynamic modeling of the beam elastic curve. Between the longitudinal (burnishing force) and transverse (slide friction force) forces exists a correlation defined by Coulomb's law of sliding friction. On this basis, an analytical relationship between the beam deflection and the sought friction coefficient has been obtained. In order to measure the deflection of the beam, strain gauges connected in a "full bridge" type of circuit are used. A flexible adhesive is selected, which provides an opportunity for dynamic measurements through the constructed measuring system. The signal is proportional to the beam deflection and is fed to the analog input of USB DAQ board, from where the signal enters in a purposely created virtual instrument which is developed by means of Labview. The basic characteristic of the virtual instrument is the ability to record and visualize in a real time the measured deflection. The signal sampling frequency is chosen in accordance with Nyquist-Shannon sampling theorem. In order to obtain a regression model of the friction coefficient with the participation of the diamond burnishing process parameters, an experimental design with 55 experimental points is synthesized. A regression analysis and analysis of variance have been carried out. The influence of the factors on the friction coefficient is established using sections of the hyper-surface of the friction coefficient model with the hyper-planes.

• Journal of Sasang Constitutional Medicine
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• v.14 no.2
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• pp.90-97
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• 2002

Sasang Constitutional Medicine is based on the diversity of human being and medically developed the variation of response to diseases and medicines. The diversity is categorized as four groups Taeyangin, Taeumin, Soyangin, Soeumin according to morphology, physiology, pathology, and pharmacology. The phenotypes of Sasang constitutions represent that constitutions may be possessed of the different genetic backgrounds. To clarify the genetic difference among the Sasang constitutions, we performed a genetic analysis with the 3'-UTR polymorphism of ADPRT (rs=8679) as a pooled DNA sequencing method. ADPRT modulates various nuclear proteins by poly(ADP-ribosy)lation and is involved in the regulation of various cellular processes such as differentiation, proliferation, and tumor transformation. This gene is also involved in the recovery of cell from DNA damage and the brain infarction. The allele frequencies of [T/C] polymorphism of ADPRT of Soeumin and Soyangin groups were (T: 0.94/C: 0.06) and that of Taeumin and Taeyangin groups were (T: l.00/C: 0.00). The allele frequency was not showed the difference between constitution groups. This result represented that the [T/C] polymorphism of ADPRT 3' UTR region was not suitable to classify the constitutions. However, this study is the first trial of Sasang classification according to genetic polymorphism and further analysis will be necessarily to classify the genetic difference of Sasang constitution.

• Animal Bioscience
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• v.34 no.5
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• pp.789-800
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• 2021

Objective: Conservation and genetic improvement of cattle breeds require information about genetic diversity and population structure of the cattle. In this study, we investigated the genetic diversity and population structure of the three cattle breeds in the Korean peninsula. Methods: Jeju Black, Hanwoo, Holstein cattle in Korea, together with six foreign breeds were examined. Genetic diversity within the cattle breeds was analyzed with minor allele frequency (MAF), observed and expected heterozygosity (HO and HE), inbreeding coefficient (FIS) and past effective population size. Molecular variance and population structure between the nine breeds were analyzed using a model-based clustering method. Genetic distances between breeds were evaluated with Nei's genetic distance and Weir and Cockerham's FST. Results: Our results revealed that Jeju Black cattle had lowest level of heterozygosity (HE = 0.21) among the studied taurine breeds, and an average MAF of 0.16. The level of inbreeding was -0.076 for Jeju Black, while -0.018 to -0.118 for the other breeds. Principle component analysis and neighbor-joining tree showed a clear separation of Jeju Black cattle from other local (Hanwoo and Japanese cattle) and taurine/indicine cattle breeds in evolutionary process, and a distinct pattern of admixture of Jeju Black cattle having no clustering with other studied populations. The FST value between Jeju Black cattle and Hanwoo was 0.106, which was lowest across the pair of breeds ranging from 0.161 to 0.274, indicating some degree of genetic closeness of Jeju Black cattle with Hanwoo. The past effective population size of Jeju Black cattle was very small, i.e. 38 in 13 generation ago, whereas 209 for Hanwoo. Conclusion: This study indicates genetic uniqueness of Jeju Black cattle. However, a small effective population size of Jeju Black cattle indicates the requirement for an implementation of a sustainable breeding policy to increase the population for genetic improvement and future conservation.

• Journal of recreation and landscape
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• v.12 no.4
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• pp.45-58
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• 2018

Place memory is a new way of seeing as a new concept of cultural landscape research. Various research works and discussions have recently spread in landscape studies. In particular, the, which is visible and material, is a medium in which collective memory is embedded in place memory. The purpose of this study is to extract places of memory from the collective memory of residents of Janghang, Korea, and to visualize it through semantic relations. For this purpose, semi-standardized interviews (34 persons) were conducted with residents, and frequency analysis and semantic network analysis were used. As a result, the interviewees recalled only 127 places in Janghang that existed between 1920 and 2010. Locals remember the city based on places of memory. This means that the city could be illustrated according to specific places that are frequently mentioned. For instance, the top 25 places (top 20%) explain 65.6% of all the places in the city, and the top 39 places (top 30.8%) could describe 78.7% of the places. Some places are referred to more frequently when they are in the city's symbolic landscape, and the city's identity is projected on them. Some places were mentioned only infrequently but were nevertheless very important places by which to understand Janghang. These places of memory have not appeared in the documentary records before, which shows the value of the collective memory of the locals and the effectiveness of the interviewing method. In the clustering of the semantic network, six groups of places appeared. The local residents remembered the modern industrial city and recalled it in connection with the sites of daily life. This shows the possibility of looking not only at public memory and famous heritage as a macro history but also at daily life and meaningful places as a micro history about locals. This study has significance as an initial research that identified and visualized places of memory from the perspective of local residents. Such an approach could be useful in the study of everyday life and the conservation of modern heritage.

• Fashion & Textile Research Journal
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• v.21 no.2
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• pp.179-188
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• 2019

Domestic apparel products labeled as 'Made in Korea' in the Chinese market are recognized as a high quality products due to the influence of the Korean Wave (Intergen Consulting Group, 2007). This study analyzes the patterns and order arrangement types of a fashion brand company commissioned to produce apparel in Seoul, Korea in order to rebuild a network of small sewing factories scattered in Korea, reorganize operations, and to find the possibility of regenerating the Korean sewing industry by establishing contact points with domestic sewing factories. We surveyed 100 apparel brand companies in Seoul listed in the 2014/2015 Korea Fashion Brand Annual (Apparel News, 2014) and conducted a questionnaire survey on the company's general management status, type of fabric materials dealt with, and major contact points and methods of production handling. The frequency analysis indicated that the main production material with cloth type was woven fabric with ladies' clothes. The Planning MD team has the highest rate of ordering production with delivery method to the production factory after purchasing fabric and trims. Most respondents answered that they would select a production factory based on recommendations from acquaintances. This was due to a lack of no objective indicator provided by the sewing factory at present and the absence of objectively proceeded communication with brand companies. In this study, we analyze various conditions and measurements for production arrangements from a fashion brand company to revitalize sewing factories in Korea.