• 한국지구물리탐사학회:학술대회논문집
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• 2005.05a
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• pp.273-280
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• 2005

Robust magneto-telluric (MT) response function estimators are now in standard use in electromagnetic induction research. Properly devised and applied, these methods can reduce the influence of unusual data (outlier) in the response (electric field) variable, but often not sensitive to exceptional predictor (magnetic field) data, which are termed leverage points. A bounded influence estimator is described which simultaneously limits the influence of both outlier and leverage point, and has proven to consistently yield more reliable MT response function estimates than conventional robust approach. The bounded influence estimator combines a standard robust M-estimator with leverage weighting based on the statistics of the hat matrix diagonal, which is a standard statistical measure of unusual predictors. Further extensions to MT data analysis are proposed, including a establishment of data rejection criterion which minimize the influence of both electric and magnetic outlier in frequency domain based on statistical distribution of electromagnetic field. The rejection scheme made in this study seems to have an effective performance on eliminating extreme data, which is even not removed by BI estimator, in frequency domain. The effectiveness and advantage of these developments are illustrated using real MT data.

• Journal of the Korea Fashion and Costume Design Association
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• v.5 no.2
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• pp.75-91
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• 2003

This study analyzed descriptions about dots, lines, and sides which are used as a basic elements to express geometric figures as followings: -In the aspect of formative art, dots form images and feelings through their concurrence when make a slight move to coordinates. The concurrence can bring out either positive or negative images; -Lines have unlimited variation as a core measure in body art. They can make optimal effects with different lines such as straight and curved lines of human body; -Sides express not only effects of texture and perspective but also of space and solid by color effects. Expressive characteristics and geometric shapes can be classified by tattoo, henna and body painting: First, colorful tattoos are favored by Caucasian and original tattoos are mostly used by yellow and colored races in the way of scarification to get decorative effects. Recently, a rapid cycle of fashion change in tattoo figures has developed a tentative method of tattooing and a variety of decoration methods. It has made it a lot easier to change a pattern of a tattoo. Tattoos are now popular among people because they no longer have to suffer from pains when they get their body tattooed for a long time. Since tattoos boast their unique beauty which consists of most dynamic and attractive images among the types of body art. It will be one of the most favored make-up methods in the nearest future. Second, geometric designs used in henna include crosses, dots, straight lines, triangles, date palms, and so on. Henna has been particularly loved as an instant decoration by the public since it gradually disappears as time goes on. Third, body painting enables to draw a three-dimensional effect because of its close relation with body movements in a limited space. Each individual will have a different feeling appealed in their body painting. Body painting has been applied to many different areas, especially to theatrical art using lights, music and performance altogether producing impromptu and experimental works. Unlike other arts such as painting, sculpture, visual and industrial arts, body painting has mobility. Since it is painted on a three-dimensional human body, it can bear originality expressing realistic objects or animals and strengthen creative functions using body lines. Moreover, geometric designs can be diversified by the sexes. As a result of analysis, geometric designs expressed in body art seemed to transcend expressions of beauty and turned out to be another way of decoration. Body art has also been used as a way to express visual integration and consolidation dynamically not by human instinct but by social changes. The needs for body art will grow as the future comes nearer and be recognized as a new and fresh value. Formative elements of geometric figures deliver visual impressions combined with human body and finally create more various types of body art in harmony of body lines.

• Korean Journal of Occupational Health Nursing
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• v.11 no.1
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• pp.63-80
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• 2002

Objectives: The objective of this study is to evaluate the job characteristics of container terminal workers by applying the Job Strain model, and to assess the relationship among the general characteristics, job characteristics and psychosocial distress. Methods: A self-administrated questionnaire survey was performed to the container terminal workers in Pusan. Among the 200 male workers who answered the questionnaires, white-collar workers and blue-collar workers were 100, respectively. Karaseks Job Content Questionnaire was utilized to evaluate the job characteristics and Psychosocial well-being index (PWI) was applied to measure the extent of their psychosocial stress. Results: In white-collar workers, the skill discretion, created skill, decision-making authority, decision-making latitude, psychological job demand, and supervisor support of the job characteristics were significantly high, while in blue-collar workers physical exertion was significantly high. The result of Psychosocial well-being index (PWI) reveals that blue-collar workers were more stressed than white-collar workers, especially, the indices of depression (factor 2), sleeping disturbance and anxiety (factor 3), General well-being and vitality (factor 4) were significantly increased; whereas, in white-collar workers, only the index of social performance and self-confidence (factor 1) was significantly increased. And PWI scores were significantly increased in the lower social support and psychological job demand. By the multiple logistic regression analysis for PWI, blue-collar workers had increased odds ratio of 2.66(95% CI;1.11-6.41) compared with white-collar workers. The unmarried workers increased odds ratio of 3.54(95% CI;1.18-10.62) compared with married workers. And workers who have not own house increased odds ratio of 2.35(95% CI;1.15-4.79) compared with workers who have own house. Particularly, odds ratio of work-shift in blue-collar workers was 11.10(2.14-57.64). Conclusion: Skill discretion, created skill, decision-making authority, decision-making latitude, psychological job demand, and supervisor support were increased in white-collar workers. Decreased skill discretion and increased physical exertion were found in blue-collar workers, which is supported the Job Strain model. Job stress of blue-collar workers was comparatively higher than that of white-collar workers, especially, skill discretion, decision-making authority, decision-making latitude, job insecurity, physical exertion were noticeable factors. Especially, sleeping, smoking, and work shifting turned out to be a main cause that increases stress. Therefore, in order to decrease the job stress, a health promotion program to change the health behaviors should be activated and an organized job stress management program should be introduced. Especially, working condition for blue-collar such as physical exertion and work-shift should be improved.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.741-744
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• 2008

Quality control of early age concrete significantly influences the long term performance. Primary factors for early age concrete quality control should include the relative humidity and temperature variation, and these are more important as structures become massive and huge. Temperature raise due to cement hydration causes stress, which can develop to cracking with internal and/or external restraints. Exposure conditions including ambient temperature, humidity and wind also significantly affect the cracking behavior of early age concrete. Among many of studies on the early age concrete behavior, investigation on the variation of temperature and relative humidity internal of concrete is not common. That is in part because the difficulties in measuring the relative humidity and temperature inside the concrete. This study used a digital sensor with an appropriate logger to measure internal temperature and relative humidity. This direct measuring method is expected to provide more reliable and comprehensive data acquisition on the early age behavior of concrete.

• Journal of the Korean Institute of Intelligent Systems
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• v.26 no.3
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• pp.182-189
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• 2016

For high accuracy of forecast using numerical weather prediction models, we need to get weather observation data that are large and high dense. Korea Meteorological Administration (KMA) mantains Automatic Weather Stations (AWSs) to get weather observation data, but their installation and maintenance costs are high. Mini-AWS is a very compact automatic weather station that can measure and record temperature, humidity, and pressure. In contrast to AWS, costs of Mini-AWS's installation and maintenance are low. It also has a little space restraints for installing. So it is easier than AWS to install mini-AWS on places where we want to get weather observation data. But we cannot use the data observed from Mini-AWSs directly, because it can be affected by surrounding. In this paper, we suggest a correcting method for using pressure data observed from Mini-AWS as weather observation data. We carried out preconditioning process on pressure data from Mini-AWS. Then they were corrected by using machine learning methods with the aim of adjusting to pressure data of the AWS closest to them. Our experimental results showed that corrected pressure data are in regulation and our correcting method using SVR showed very good performance.

• Korean journal of communication and information
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• v.26
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• pp.45-82
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• 2004

The purpose of this study is to examine the concept of civic journalism and the contents of Korean Internet newspapers that might reflect the possibilities of this new medium for civic journalism practices. This study examined how far and deep civic journalism practices have extended into Korean Internet newspapers as journalism's new tradition. More specifically, this study analyzed news articles of Korean Internet newspapers to uncover any differences among civic journalism Internet newspapers with different citizen reporter systems. The composite measure based upon ten elements of civic journalism practices was used as indicator of civic journalism practices. To obtain systematic data on news offered by Korean Internet newspapers on the World Wide Web, four major Internet newspapers, including Ohmynews, Ngotimes, Netpinion and Pressian were examined by a content analysis in April and May of 2003. Findings of this study reveal that many Korean newspapers do not fully exploit the opportunities and advantages offered by the new medium for civic journalism practices in online environments. Both aggregate and individual level of analysis for the civic journalism index reveal that there are some differences between non-civic journalism and civic journalism Internet newspapers using citizen reporter systems. However, overall performances of civic journalism Internet newspapers are not good enough to support the argument that civic journalism is well practiced in Korean Internet newspapers. Nonetheless, it would not be fair to conclude that Korean Internet newspapers have totally ignored the Internet's potential to increase the civic journalism performance in online environments.

• Journal of IKEEE
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• v.22 no.2
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• pp.495-498
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• 2018

In this paper, we propose an DAP system for dose evaluation of medical and industrial X-ray generator. Based on the DAP measurement technique using the Ion-Chamber, the proposed system can clearly measure the exposure radiation dose generated by the diagnostic X-ray apparatus. The hardware part of the DAP measures the amount of charge in the air that is captured by an X-ray. The high-speed processing algorithm part for cumulative radiation dose measurement through microcurrent measures the amount of charge captured by X-ray at a low implementation cost (power) with no input loss. The wired/wireless transmission/reception protocol part synchronized with the operation of the X-ray generator improves communication speed. The PC-based control program part for interlocking and aging measures the amount of X-ray generated in real time and enables measurement graphs and numerical value monitoring through PC GUI. As a result of evaluating the performance of the proposed system in an accredited testing laboratory, the measured values using DAP increased linearly in each energy band (30, 60, 100, 150 kV). In addition, since the standard deviation of the measured value at the point of 4 division was ${\pm}1.25%$, it was confirmed that the DAP showed uniform measurements regardless of location. It was confirmed that the normal operation was not less than ${\pm}4.2%$ of the international standard.

• Journal of IKEEE
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• v.23 no.4
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• pp.1457-1460
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• 2019

In this paper, we proposed the development of a mixed sensor parts for integrated radiation exposure protection fireman's life-saving alarm that can be location-tracked and irradiated. To measure radiation exposure dose, we use the PIN-Diode radiation measurement sensor module, a semi-conductive radiation measurement sensor that can minimize size and weight. The design for removing leakage current is carried out to enhance the characteristics of the radiation measurement sensor using PIN-Diode. The IMU sensor module is used to estimate the location of the current fireman at the same time as the accident estimate by adding together the data and the values for acceleration on the three axis. Experiments were conductied by an authorized testing agency to determine the efficiency of the proposed mixed sensor parts for integrated radiation exposure protection fireman's life-saving alarms. The cumulative dose measurement range was measured in the range of 10 μSv to 10 mSv, the highest level in the world. The accuracy was measured from ±6.3% to ±9.0% (137 Cs) and normal operation was found at the international standard of ±15%. In addition, positional accuracy was measured within ±10%, resulting in a high level of results, demonstrating its effectiveness. Therefore, it is expected that more firemen will be able to provide with superior performance integrated radiation exposure protection fireman life-saving alarm.

• Journal of Environmental Science International
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• v.17 no.3
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• pp.305-314
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• 2008

As forest land takes up 65% of the Korean peninsula, there have been continuing conflicts between the development and conservation of forest land. As the income level has changed over time, the usage of forest land in society has changed. There has been increasing demands for forest land for urban development and recreational use. On the other hand, a large proportion of the land is required to be preserved for the forest and the natural ecosystem in it. The existing management system for the forest land has been designed focusing on the management of the trees on the land, and not the land itself. Due to this limitation, the current management system of forest land has failed to protect the forest land from being developed indiscreetly, making it difficult to conserve and develop the forest land in an efficient way. A major question in forest land management is how to integrate economic use activities with the supporting ecosystems to maximize performance of the ecological-economic system. In order to promote sustainable use of forest resources, and to achieve efficient forest land management, it is prerequisite to evaluation on forest resources of natural ecosystems. Quantitative measures are needed that signify how necessary the services and products of forested ecosystems are to human endeavors. In this study, the natural wealth provided by forest land was quantified based on emergy synthesis. Emergy is a universal measure of real wealth of the work of nature and society made on a common basis. Thus, Calculations of emergy provide a basis for making choices about environment and economy following the general public policy to maximize real wealth. The goals of forest land management to achieve balance between the ecology and economy of its integrated system and to foster equity among the diverse outcomes of the forest land were assessed with emergy. Emergy was demonstrated to holistically integrated and quantify the interconnections of a coupled nature-human system allowing the goals of ecological balance and outcome equity to be measured quantitatively. Doing so will provide a better understanding of the basis of forest land wealth and the consequences of management decisions.

• The Journal of Korean Academy of Prosthodontics
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• v.44 no.5
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• pp.594-605
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• 2006

Statement of problem: Modification of titanium implant surface has potential to ensure clinically favorable performance that several surface modification technologies have been introduced. Among the methods. anodizing method and sol-gel hydroxyapatite coating method have gained much interest due to its roughness and chemical composition of the coating layer, but more of its biocompatibility result is required. Purpose : The purpose of this study was to compare bone-implant interface shear strength of four different surface treated implants as time elapsed. Resonance frequency analysis(RFA) and removal torque measurement methods were employed to measure implant stability at one week and six week after implantation. Material and method: A total of 80 screw-shaped implant [20 machined, 20 resorbable media blasted(RBM), 20 anodized, and 20 anodized+hydroxyapatite sol-gel coated] were prepared, and one of each group was implanted in the tibia of a New Zealand white rabbit that total 20 of them were used. In order to test the implant stability and implant-tissue interface contact changing in the bone bed, each 10 rabbit were sacrificed 1 week and 6 week later while resonance frequency and removal torque were measured. One-way analysis of variance and the Tukey test were used for statistical analysis. Results : The results were as follows. 1. There was no statistically significant difference of implant stability quotients(ISQ) value in RFA between individual groups after 1 week of implantation and 6 weeks(p>0.05). But, there was statistically significant increase of ISQ value in 6 weeks group compared to 1 week group(p<0.05). 2. There was no statistically significant difference in removal torque analysis between individual groups after 1 week of implantation and 6 weeks(p>0.05). but there was statistically significant increase in all 4 groups after 6 weeks compared to 1 week later(p<0.05). 3. There was no statistically significant difference in removal torque analysis between anodized group and HA coating after anodic oxidation 6 weeks later(p>0.05), but significant difference was appeared in both groups compared to RBM group and smooth-machined group(p<0.05). Conclusions : It can be suggested that changes in surface characteristics affect bone reactions. Anodized and anodized+hydroxyapatite sol-gel coating showed significantly improved bone tissue response to implants, but further study on the effect of hydroxyapatite dissolution is needed.