• Industrial Engineering and Management Systems
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• v.10 no.3
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• pp.197-202
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• 2011

In traditional production lines, such as assembly lines, each worker is usually assigned to a particular fixed work, and decreasing the task to master the assigned work is valuated. However, when an imbalance exists between workers' speeds, if a worker delays the overall work in the production line, the production rate of the particular line will also decrease. To avoid this problem, the "Self-Balancing Production Line" was introduced. In this type of production line, each worker is assigned work dynamically, and when specific conditions are satisfied, production remains balanced. Characteristics of these lines that can be preempted at any place have already been analyzed by some researchers. A previous paper examined the situation in which only a single worker can process one machine and cannot preempt processing, and the improved policy of an ordinary selfbalancing production line, which specifies which stations workers can process and how workers can behave. This policy achieveda high production rate with only four stations and two workers (Buzacott, 2002). In that paper, worker processing stations and the behavior of a specific worker were limited, andthe paper focused only on specific stations and workers. Therefore, it is not applicable to any worker sequence. In this paper, we focus on other ways to decrease cycle time. In this kind of line, a worker processes at his or her speed. Therefore, if a worker is assigned stations according to his or her speed, the line can decrease cycle time. To do so, we relax the assumptions of this type of line and set a new condition. Under these conditions, we compare our results to the results of previous papers.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.5
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• pp.18-28
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• 2009

To analyze influences under faults caused by a stator winding short and to evaluate an effectiveness of a diagnostic algorithm a faulty model for an inverter-driven permanent magnet synchronous motor is presented. Even though the conventional dq motor model obtained through the transformation of phase voltage model is widely used to analyze and control the motor, it can not be used in the analysis of a faulty motor since the 3-phase balanced condition is no longer hold under the fault caused by a stator winding short, and thus, it is very difficult to obtain motor input voltages from the pole voltage of an inverter. To overcome this problem, a faulty model for an inverter-driven permanent magnet synchronous motor is proposed by considering the line voltage of 3-phase variables. The effectiveness of the proposed faulty model is verified through comparative simulations and experiments using DSP TMS320F28335 and motor built to allow a partial short of inter-turn.

• Korean Journal of Community Nutrition
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• v.10 no.2
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• pp.163-173
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• 2005

School Lunch Program (SLP) should provide adequate and qualitative nutritional food for student's growth and proper food habit. With this fact, this study divided 524 middle school students who resided in Jeonju, Jellabukdo into two groups, SLP or non SLP according to whether they were provided SLP or not. Then this research estimate each group's nutritional knowledge, nutritional attitude, dietary behavior, balance of three meals, and health checking their clinical symptom to investigate the effects of the SLP. This research applied anthropometric data, questionnaires and food intake data using 24 hours recall method. Each group's age average was same as 14.0 years old respectively. The average score of nutritional knowledge and condition of balance of lunch were significantly higher in SLP group than those of non-SLP group, although, there were no significant differences in the scores of nutritional attitude, dietary behavior, and balance of breakfast and dinner within both groups. This research showed that SLP had positive role on nutritional knowledge and balanced lunch. However, current SLP is not sufficient to cause change the nutritional attitude and dietary behavior. To make more applicable and effective result of SLP leading nutritional attitude changes and development of appropriate dietary behavior, certain level of nutritional education to the student may be important.

• Korean Journal of Human Ecology
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• v.18 no.4
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• pp.959-970
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• 2009

The purpose of this study was to evaluate the dietary habit, nutritional condition and quality of everyday meal for college students. The number of the subjects was 102 and they were divided into three groups by their residing types; students living with their parents (n=34), students living in dormitory (n=34) and students living independently off the campus (n=34) Questionnaire, 24hour dietary recall for food intakes, and body composition analysis were used. SPSS program was used for the statistics. In general health matter, the average age for each group of students was $21.2kg/m^2$, $20.9kg/m^2$, and $21.9kg/m^2$ respectively. And heights, weights, muscle mass, body fats and BMI were not significantly different between groups. Results on dietary habit showed that students living with their parents had better meal pattern and regularity for breakfast than other groups. Also, for dietary evaluation, students living with their parents showed better extent of intake of milk than other groups. Evaluation on nutrients intake showed that amount of calcium, vitamin $B_2$, folic acid intake in student living independently off the campus were lower than those of the other groups(P<0.05). And MAR(Mean Adequacy Ratio) was not significantly different between groups, however INQ(Index of Nutritional Quality) and NAR(Nutrient Adequacy Ratio) of calcium were lower in off the campus group than other two groups. In conclusion, students living independently had worse eating habits and showed lower intake of calcium than those living with their parents or living in a dormitory. Therefore nutritional education for improving well-balanced dietary habits and optimal intake of nutrients are required especially for students living independently off the campus.

• Journal of Korean Society of Rural Planning
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• v.26 no.1
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• pp.123-136
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• 2020

The paradigm of rural development projects has shifted and expanded from agricultural production based on the way of improving the residential environments in order to achieve the quality of life staying in rural areas. The purpose of this study is to evaluate policy directions of rural development projects by investigating government projects conducted successively starting from the Participatory Government of President Roh in 2003 and to the present Government of President Moon. In consideration of administrative affairs, the projects include the Balanced National Development Project, Quality of Life Improvement and Regional Development for Rural Villages Projects. The study examined changes in visions and key agendas proposed in national affairs as well as those in the visions and strategies exhibited by local development project plans through various governments. The core contents examined are the project characteristics, transformation process through government changes, and the law of status pertaining to rural development projects. The direction of implementation for the rural development projects implemented by each government provide an opportunity of understanding the transformation process in each project that has been still effective currently. This study is expected to provide a basic set of data to be used for a proposal for new rural development projects while still being useful to be referred or integrated to other national and regional projects.

• Korean Journal of Community Nutrition
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• v.18 no.5
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• pp.467-477
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• 2013

This study examined the health-related factors and nutritional status of 89 single women workers in their 20's who work night and day shift at the take-out coffee shops and the 89 single women office workers. The results of the study are summarized as follows: The shift-workers showed lower rate of office tenure (p < 0.001), income (p < 0.001), job satisfaction (p < 0.05), weight (p < 0.05), and higher rate of weight change (p < 0.001) than the non shift-workers. The shift-workers showed lower rate of of exercise (p < 0.001), sleeping hours (p < 0.01), and good health condition (p < 0.01), and higher rates of smoking (p < 0.001), presence of disease (p < 0.001), gastric and intestinal illnesses (p < 0.001) than the non shift-workers. More than 88.8% of the shift workers answered that they ate alone (p < 0.001). The shift workers showed lower rate of regularity of meal (p < 0.001), balanced diet (p < 0.001), and mealtime (p < 0.001), and higher rate of skipping breakfast (p < 0.001), consumption of salty and spicy food (p < 0.001), and overeating (p < 0.01) than the non shift-workers. The shift workers consumed (p < 0.001) less frequently rice, soup and side dishes, and more frequently noodles and snack, bread than the non-shift-workers. The shift workers showed lower rate of consumption of beer (p < 0.01), and higher rate of consumption of coffee (p < 0.001), tea (p < 0.01) and soju (p < 0.001) in once a week or more intakes than the non-shift-workers. The shift workers showed higher rate of consumption of carbohydrates (p < 0.05), and calcium (p < 0.05) and lower rate of consumption of protein (p < 0.05), fiber (p < 0.05), vitamin C (p < 0.05), and folate (p < 0.05) intakes than the non-shift-workers.

• Proceedings of the Botanical Society of Korea Conference
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• 1999.07a
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• pp.85-89
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• 1999

Somatic embryogendesis is one of good examples of the basic research for plant embryo development as well as an important technique for plant biotechnology. This paper describes the direct somatic embryogenesis from zygotic embryos of Panax ginseng is reversely related to normal axis growth of zygotic embryos by the experiment of various chemical treatments. Under the normal growth condition, the apical tips of embryo axis produced an agar-diffusible substance, which suppressed somatic embryo development from cotyledons. Although the cells of zygotic embryos were released from the restraint of embryo axis, various factors were still involved for somatic embryo development. Electron microscopic observation revealed that the ultrastructure of cells of cotyledon epidermis markedly changed before initiation of embryonic cell division, probably indicating reprogramming events into the cells embryogenically determined state. Polar accumulation of endogenous auxin or cell-cell isolation by plasmolysis pre-treatment is the strong inducer for the somatic embryo development. The cells for the process of somatic embryogenesis might be determined by the physiological conditions fo explants and medium compositions. Direct somatic embryos from cotyledons fo ginseng were originated eithrer from single or multiple cells. The different cellular origin of somatic embryos was originated either from single or multiple cell. The different cellular origin of somatic embryos was depended on various developmental stages of cotyledons. Immature meristematic cotyledons produced multiple cell-derived somatic embryos, which developed into multiple embryos. While fully mature cotyledons produced single cell-derived single embryos with independent state. Plasmolysis pretreatment of cotyledons strongly enhanced single cell-derived somatic embryogenesis. Single embryos were converted into normal plantlets with shoot and roots, while multiple embryos were converted into only multiple shoots. GA3 or a chilling treatment was prerequisite for germination and plant conversion. Low concentration of ammonium ion in medium was necessary for balanced growth of root and shoot of plantlets. Therefore, using above procedures, successful plant regeneration of ginseng was accomplished through direct single embryogenesis, which makes it possible to produce genetically transformed ginseng efficently.

• Journal of the Ergonomics Society of Korea
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• v.30 no.5
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• pp.671-681
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• 2011

Objective: The purpose of this study is to compare the workload level at each lower limbs posture and suggest the ergonomic workstation guideline for working period by evaluating the imbalanced lower limbs postures from the physiological and psychophysical points of view. Background: Many workers like welders are working in various imbalanced lower limbs postures either due to the narrow working conditions or other environmental conditions. Method: Ten male subjects participated in this experiment. Subjects were asked to maintain 3 different lower limbs postures(standing, squatting and bending) with 3 different working conditions(balanced floor with no scaffold, imbalanced floor with 10cm height of scaffold, and imbalanced floor with 20cm height of scaffold). EMG data for the 4 muscle groups(Retus Femoris, Vastus Lateralis, Tibialis Anterior, Gastrocnemius) from each lower limbs posture were collected for 20 seconds every 2 minutes during the 8 minutes sustaining task. Subjects were also asked to report their discomfort ratings of body parts such as waist, upper legs, lower legs, and ankle. Results: The ANOVA results showed that the EMG root mean square(RMS) values and the discomfort ratings(CR-10 Rating Scale) were significantly affected by lower limbs postures and working time(p<0.05). The correlation was analyzed between the EMG data and the discomfort ratings. Also, prediction models for the discomfort rating for each posture were developed using physical condition, working time, and scaffold height. Conclusion: We strongly recommend that one should not work more than 6 minutes in a standing or squatting postures and should not work more than 4 minutes in a bending posture. Application: The results of this study could be used to design and assess working environments and methods. Furthermore, these results could be used to suggest ergonomic guidelines for the lower limbs postures such as squatting and bending in the working fields in order to prevent fatigue and pain in the lower limbs body.

• Journal of architectural history
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• v.14 no.4 s.44
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• pp.7-28
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• 2005

We are so used to the concept of the term 'space' that we do not question its conceptual validity. However, this paper argues that the notion of space prevailing all over the world, is not a universal concept that can be applicable to all architectures of the world, but is a particular concept that is generated from the Western way of thinking. This paper alms to identify the conceptual structure of the idea of space as it is originated in the tradition of the West, and, as an alternative view of space, tries to identify the nature of the view of space perceived in the tradition of the Eastern architecture. Comparison of the two views, that of the East and the West, and their meaning in the future of architecture, is another task to discuss in this paper. To be able to clarify the meaning of space in East Asian tradition, a set of new perspective of understanding of space was invited. They are ; 1. sky-earth(天地); insisting that the notion of space should be replaced within the context of sky, which is one half of sky-earth totality 2. energy of the air (空氣), space is not empty part inside of a building, but is a dynamic condition of air that is a part of the sky which always exist in form of energy 3. place(자리): instead of space, which, basically. is a man-made concept, idea of place is necessary, which include not only space but also earth Such concept of space which is different from the notion of space of the West, is meaningful not only to identify the idea of space in the East, but also to be able to contribute for more dynamic, varied, and balanced understanding of space.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.1
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• pp.84-92
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• 2000

A GaAs MESFET MMIC transmitter for 2.4 GHz wireless local loop handset is designed and fabricated. The transmitter consists of a double balanced active mixer and a two stage driver amplifier with voltage negative feedback. In particular, a pair of CS-CG(common source-common gate) structure compensates the reduction in dynamic range caused by unbalanced complementary IF input signals. And to suppress the leakage local power at RF port, the mixer is designed by using phase characteristic between the ports of MESFET. At the bias condition of 2.7 V and 55.2 mA, the fabricated MMIC transmitter with chip dimensions of $0.75\times1.75 mm^2$ obtains a measured conversion gain of 38.6 dB, output $P_{idB}$ of 11.6 dBm, and IMD3 at -5 dBm RF output power of -31.3 dBc. This transmitter is well suited for WLL handset.