• The korean journal of orthodontics
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• v.22 no.1
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• pp.241-251
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• 1992

The purpose of this study was to investigate the root resorption pattern in incisors in dog under intrusive orthodontic loadings of various magnitude and duration. Intrusive forces were generated by closed coil springs. Force magnitudes were 15-30gm, 50-60gm and 80-110gm. Durations were continuous and intermittent. Intermittent duration was applied at intervals of 12 hours. The readjustment of the force was done every 4 days. The forces were maintained for 30 days. All specimens were decalfied, embedded in paraffin and stained with hematoxylin-eosin stain. Observations were made with light microscope. The following results were obtained; 1. The continuity of root surface was ceased in all, except intermittent forced teeth with 25gm. 2. The root resorptions, cementoclasts and cemental lacunae, were increased around periapical regions and the destructive scope of bone was deeply extended as the exerted orthodontic forces increased. 3. It was inspected that, under the same forces, root resorption and bone destruction were more deeply appeared in the continuously forced teeth than the intermittently forced ones. 4. All of the alveolar bone, showed direct and undermining bone resorptions.

• Korean Institute of Interior Design Journal
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• v.22 no.1
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• pp.239-246
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• 2013

This study is aimed at understanding the color extendibility of color-field abstract through Mark Rothko's paintings. Color extendibility is a structure applied by Mark Rothko. He simplifies it and by pursuing autonomy and immediacy of the color itself, including surface color and the front of color-field, Rothko creates value through motions in his square paintings of non-fixed shapes. Chapter 2 revisits the meaning of color in abstract expressionism and explains the principle of color-field by applying the concept of ergon and parergon. In chapter 3, the principle, processes, methods, techniques of expression were studied as a basis to understand color extendibility and color-field abstract. In chapter 4, the works of Mark Rothko were analyzed based on his multiform paintings(1946-1948), number and untitled(1949-1957), and black paintings(1958-1970) in order to identify, in the final chapter, the features of color extendibility in Rothko's works. According to the above research, the thesis successfully concludes that the artist's reconstruction of reality and readjustment of transcendent reality are reproduced via color extendibility, the movement of color-field.

• Proceedings of the KIEE Conference
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• 2002.11b
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• pp.41-43
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• 2002

The contracted electric power and the demand factor of customers are used to predict the peak load in distribution transformers. The conventional demand factor was determined more than ten years ago. The contracted electric power and power demand have been increased. Therefore, we need to prepare the novel demand factor that appropriates at present. In this paper, we modify the demand factor to improve the peak load prediction of distribution transformers. To modify the demand factor, we utilize the 169 data acquisition devices for sample distribution transformers in winter, spring summer. And, the peak load currents were measured by the case studies using the actual load data, through which we verified that the proposed demand factors were correct than the conventional factors. A newly demand factor will be used to predict the peak load of distribution transformers.

• Journal of Korean Medicine Rehabilitation
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• v.19 no.2
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• pp.213-225
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• 2009

Objectives : The purpose of this study was to investigate the factors related on pain in female office workers. Methods : Neck pain group of 31 female subjects complained of neck and arm discomfort. Normal group of 20 female subjects had no complaints or minimal discomfort. Cervical curvature and muscle tone were assessed by whole spine x-ray, meridian-electromyography(MEMG), craniovertebral angle, and Moire. Neck pain was evaluated by Neck Disability Index(NDI) and Visual Analog Scale(VAS). The emotional and other physical factors that could effect neck pain were checked by questionnaires including Beck Depression Index(BDI), Stress Reaction Index(SRI), Holmes & Rahe Social Readjustment Rating Scale(SRRS), International Physical Activity Questionnaire(IPAQ), and Gastrointestinal Symptom Rating Scale(GSRS). Results : The contraction and fatigue of upper trapezius by MEMG was significantly higher in the neck pain group. And BDI, SRI, SRRS, and GSRS were significantly higher in the neck pain group (p<0.05). However, there was no significant difference in the Jackson's angle, Cobb's method, craniovertebral angle, and moire between two groups. Conclusions : The results suggest that neck pain is related to mental stress rather than physical stress and physical stress does not change cervical curvature significantly.

• Journal of Oral Medicine and Pain
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• v.17 no.1
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• pp.51-60
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• 1992

44 Temporomandibular Disorders(TMDs) patients with non-trauma and non-iatrogenic origin pressented at Wonkwang University Dental Hospital. They were grouped into experimental subjects and 85 persons without TMSDs were classified into control groups. The objectives of this study was to investigate the effects of recent life changes on the symptom severity and treatment course of TMDs. For that purpose, the author used several scales and indices, namely, Social Readjustment Rating Scale(SRRS) devised by Holmes and Rahe, SRRS-Korean revision by Hong and Jeong, Helkimos Anamnestic index, Clinical Dysfunction index, and Visual Analogue Scale treatment index(VAS Ti) transformed from VAS by the author. Data resulted from the investigation were collected by scale or index and processed with SPSS. The obtained results were as follows : 1. Life change units(LCU) and values of indices of experimental group were higher than those of control group. 2. Life change units recorded with SRRS-Korean revision were higher than those with original SRRS in all cases and significant positive correlations existed, between he two Therefore, clinical use of original SRRS in Korea is reliable and valid. 3. In experimental group, LCU were positively correlated with Helkimos Clinical Dysfunction index and VAS treatment index, but in control group LCU were not correlated with any items. From this, increase of life changes in patient with TMDs is likely to aggravate TMJ dysfunction and more likely to complicate treatment course.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.30 no.2
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• pp.44-50
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• 2007

This paper deals with the problem of scheduling jobs and rate-modifying activities on parallel machines. A rate-modifying activity is an activity that changes the production rate of equipment such as maintenance and readjustment. If a job is scheduled after the rate-modifying activity, then the processing time varies depending on the modifying rate of the activity. In this study, we extend the single machine problem to parallel machines problem and propose algorithms is to schedule the rate-modifying activities and jobs to minimize the makespan on parallel machines which is NP-hard. We propose a branch and bound algorithm with three lower bounds to solve medium size problems optimally. Also we develop three heuristics, Modified Longest Processing Time, Modified MULTIFIT and Modified COMBINE algorithms to solve large size problems. The test results show that branch and bound algorithm finds the optimal solution in a reasonable time for medium size problems (up to 15 jobs and 5 machines). For large size problem, Modified COMBINE and Modified MULTIFIT algorithms outperform Modified LPT algorithm in terms of solution quality.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.129-134
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• 2005

The behavior of whole system is affected by a minor change of system in the hydronic radiant floor heating system. Under partial load condition, the change of system resistance causes overflow of supply water. This unexpected effect is the cause of several problems in the heating system. In this study, we find some factors were validated with several computer simulations. After validation of this result, several conceptual solutions are evaluated to prevent overflow.

• Journal of the Korean Society for Railway
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• v.5 no.3
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• pp.148-157
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• 2002

A health monitoring system becomes a useful tool to obtain information on long term behavior of the important railway structures such as very long span and special type bridges. The health monitoring system not only gives the direct measurement data of the railway bridges but also provides the basic data on the maintenance of the structures. Therefore, periodic calibrations of the health monitoring system will be a necessary step toward precise and accurate assessment of the railway bridges. In this study, the calibration and gauge factor readjustment process made for the health monitoring system installed in the railroad bridges is reviewed and some findings are explained in detail: specifically, the calibrators made for this purpose are illustrated and the regression processes of the calibration on long-term displacement using water level sensor, longitudinal displacement using LVDT sensor, instantaneous displacement using LVDT sensors and accelerometer are described in full length. Based on the regression results, it was found that the gauge factors need to be readjusted according to the regression equation but, since the deviation or shift is not serious so far, long-term observation on each sensor is also recommended. Future work will be concentrated on the long-term analysis of each sensor and on the database creation so that the assessment of the structures is possible.

• Korean Journal of Psychosomatic Medicine
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• v.5 no.1
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• pp.129-134
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• 1997

The meddle years start when persons achieve maturity and end when they realize they are old, and we commonly call ages between thirty-live and sixty five the middle years. Thinking of life as a play, the middle years lead up to and away from the climax of the plot. In the early part of middle age, the man is the main support of his family, and is out to establish himself in his career. He is in a race toward success, and may acquire a sponsor who picks him out as a protege. In the middle part of middle age, the man is ready to come into his own and may break with his sponsor. Most persons are now at the height of their potential, know their areas of competence, and have the satisfaction of feeling in control in them. They need no longer prove themselves from day to day, for they are credited with past accomplishments. Some are caught in "promotion or success depression", and some continue to change jobs creating difficulties is readjustment. The more satisfactory changes usually occur within a career rather than through shifiting careers. In e later part of the middle age the man worries about his physical health, and experiences depression in facing the retirement. Woman frequently change the course of their lives some time between the ages of thirty-five and forty, and may resume their education or careers. Tee quarters of women are passing through "involutional melancholia".

• Journal of Environmental Science International
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• v.13 no.10
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• pp.871-882
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• 2004

Korea's national park system resembles that of Japan in many ways. In this study, National park Systems of the two countries are compared from a standpoint of their historical backgrounds to be formed and in aspect of its conservation by the main revision of national park laws in perspective. In conclusion it was found out that Korea's toleration-based regulations on building park amenities have gradually neglected the park conservation effort, whereas Japan's authorization-oriented regulations have streng thened their emphasis on park conservation. From the comparison as above, the polices to be modified for Korean national park are proposed as follows: 1. National park system, which values diversity of species, is to be proposed. For this, the Article 8 which allows a development of National parks, Enforcement Ordinance Article 4, The Article 18 of Law, Enforcement Regulation Article 6 & 7 of National Park Law should be reviewed for deletion and revision. 2. On the basis of the laws, zoning system should be readjusted by discriminated conservation policy. Also, the readjustment of zoning system should be enforced after thorough analysis and research on the value of natural resources in the national park. 3. Korea should closely review the recently revised Japanese laws on the national parks and nature revitalization promotion for applying them to conservation policy of Korean national parks.