• Journal of the Korean Geotechnical Society
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• v.34 no.7
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• pp.39-49
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• 2018

Jacked pile that involves the use of hydraulic jacks to press the piles into the ground is free from noise and vibration, and is possibly installed within a limited construction area. Thus, as an alternative to conventional pile driving methods, pile jacking could become widely accepted for the construction projects in urban area (e.g., reconstruction or remodeling construction projects). Great concern has arisen over the prediction of axially loaded jacked pile behavior. Against this background, a series of pile load tests were hence conducted on a jacked steel pipe pile installed in weathered zone (i.e., weathered soil and weathered rock). From the test results, base resistance and shaft resistance for each test condition were evaluated and compared with the values predicted by the previous driven pile resistance assessment method. Test results showed that the previous driven pile resistance assessment method highly underestimated both the base and shaft resistances of a jacked pile; differences were more obviously observed with the shaft resistance. The reason for this discrepancy is that a driven pile normally experiences a larger number of loading/unloading cycles during installation, and therefore shows significantly degraded stiffness of surrounding soil. Based on the results of the pile load tests, particular attention was given to the modification of the previous driven pile resistance assessment method for investigating the axially loaded jacked pile behavior.

• Journal of the Korean Magnetics Society
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• v.25 no.6
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• pp.189-197
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• 2015

As enforced the regulation of fuel efficiency, the electrification of automotive components in internal combustion vehicle has been applied instead of hydraulic pressure. A typical example of such parts is the EPS (electric power steering), and it is applied to most automotive at present. In electric power steering system, the core component is motor. The reduction of cogging torque and torque ripple is required to improve steering feeling and reduce NVH (Noise Vibration Harshness) in EPS. Generally the skewed design of stator or rotor is applied in order to reduce cogging torque and torque ripple. This paper propose the design and analysis methodology of Brusheless PMSM (Permanent Magnet Synchronous Motor) which is applied to skewed stator. The proposed methodology is as follows: First Intial Design PMSM with skewed stator for EPS, Second Optimal design using RSM (Response surface method), Third Performance Analysis such as Phase Back EMF, Inductance, Load torque using FEA (Finite Element Method). Finally, the reliability of proposed design methodology will be verified through the experiments of prototype sample.

• Review of Culture and Economy
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• v.17 no.2
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• pp.81-102
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• 2014

As carbon dioxide, the main greenhouse gas, is generally emitted by vehicles, the development and distribution of electric cars is important for the sustainability of environmentally-friendly tourism, especially in national parks. National parks in Korea, however, still see the use of traditional vehicles powered by internal combustion engines in the handling of visitors and the transportation of goods and staff. Such engines being the cause of environmental problems such as exhaust emission and noise pollution, the introduction of electric cars in national parks is needed. This study aims to analyze the economic value of electric cars in national parks as well as contribute to the development of the Green Transportation model in tourism destinations. The study used a logit model to estimate the willingness to pay for the introduction of electric cars in national parks. Adults over the age of twenty, with gender and age apportioned equally, were surveyed using questionnaires that included dichotomous as well as demographic questions. The findings show that the amount an individual is willing to pay for the purpose of environmental conservation is 3,948 won, while the value the national parks would derive from the use of electric cars is 56,138,130,000 won. The introduction of electric cars in national parks is expected to offer both direct and indirect benefits while helping to improving the environment of the national parks by eliminating exhaust emission and noise. This introduction would also be a response to climate change that can be taken by society as a whole.

• Journal of Digital Convergence
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• v.20 no.5
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• pp.463-476
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• 2022

After industrialization in the past, the automobile industry has continued to grow centered on internal combustion engines, but is facing a major change with the recent 4th industrial revolution. Most companies are preparing for the transition to electric vehicles and autonomous driving. Therefore, in this study, topic modeling was performed based on LDA algorithm by collecting 4,002 domestic papers and 68,372 overseas papers that contain keywords related to CASE (Connectivity, Autonomous, Sharing, Electrification), which represent future automobile trends. As a result of the analysis, it was found that domestic research mainly focuses on macroscopic aspects such as traffic infrastructure, urban traffic efficiency, and traffic policy. Through this, the government's technical support for MaaS (Mobility-as-a-Service) is required in the domestic shared car sector, and the need for data opening by means of transportation was presented. It is judged that these analysis results can be used as basic data for the future automobile industry.

• Journal of Sasang Constitutional Medicine
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• v.11 no.1
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• pp.63-77
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• 1999

This research was intended to make the writer and the written times of "Dongyi Suse Bowon Sasang ChobonGuen" clear. Considering the contents of "Dongyi Suse Bowon Sasang ChobonGuen", it was the manuscripts of "Dongyi Suse Bowon". So it was written by Lee Je-ma and it was written when he was in the late of 40s and the beginning of the 50s. The chapter of "The origin of human being" was the manuscript of the "Dongyi Suse Bowon" and it had many clues to understand the view points to recoginze the human being, and the chapter of "The herbology and The prescription" had many drafts of original prescription of the "Dongyi Suse Bowon". 'Bangang-tang' is the original prescription of 'GyejiBanhaSnggang-tang' of "Dongyi Suse Bowon" and 'GumiChyunMunDong-tang' is the original prescription of 'CheongsimYeonja-tang' of "Dongyi Suse Bowon". Compared with the 'The pharmacology' of "Dongyi Suse Bowon", it showed the order when the pharmacology of each constitution was completed. The pharmacology of Soyangin was completed the early ears of his c1inical experience, and secondly that of Taeumin was completed, and that of Soeumin was completed in the end.

• Journal of Sasang Constitutional Medicine
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• v.11 no.2
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• pp.151-183
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• 1999

The object of this study was 200 patients who had been treated in the Oriental Medical Hospital at Dong Eui Medical Center during 9 months from Jan. 1999 to sept. 1999. We proceeded the judgment of Sasang Constitution according to 'Questionnaire of Sasang Constitution Classification (I)', and 'Questionnaire of Sasang Constitution Classification II(QSCCII)' and the diagnosis by a medical specialist. The following conclusion were made in comparison with Sasang Constitution and Questionnaire. 1. We selected the 84 subjects what had the statistical value out of the 196 subjects('Questionnaire of Sasang Constitution Classification (I)' had the 71 subjects and 'Questionnaire of Sasang Constitution Classification II(QSCCII)', had the 121 subjects). And we selected again the 73 subjects('Questionnaire of Sasang Constitution Classification (I)', had the 33 subjects and 'Questionnaire of Sasang Constitution Classification II (QSCC II)' had the 40 subjects) out of the 84 subjects, because it had a repeated subjects. 2. We made the Questionnaire what has the 85 subjects, including the subjects what was approved its statistical value by 'A CLINICAL STUDY OF THE JUDGMENT OF SASANG CONSTITUTION ACCORDING TO QUESTIONNAIRE' and 'A CLINICAL STUDY OF THE TYPE OF DISEASE AND SYMPTOM ACCORDING TO SASANG CONSTITUTION CLASSIFICATION'. The subject what ask the physique and the body form was 7, the subject what ask the external appearance and the posture was 7, the subject what ask the habit and the character was 3, the subject what ask the physiology and the pathology was 3, the subject what ask the phenomenon that he has frequency was 4, the subject what ask the eating was 3, the subject what ask the symptom that he has frequency was 14, the subject what ask the work and the qualities-defects was 6, the subject what ask the friendly intercourse was 7, the subject what ask the usual mind was 5, the subject what ask the emotional inclination was I, the subject what ask the behavioral inclination was 10, the subject what ask the character was 15. 3. In the new Questionnaire, the subject what has relevance to Soyang was 84, the subject what has relevance to Soeum was 87, the subject what has relevance to Taeeum was 70. And we made the point of subject with the statistical ratio. The total point of Soyang was 7785.04, the total point of Soeum was 7742.80, the total point of Taeeum was 7746.60. 4. As a result of judgment of Sasang Constitution between the clinical diagnosis by a medical specialist and the new Questionnaire, the diagnostic accuracy of new Questionnaire was 73.33%. The diagnostic accuracy of Soyang was low, the others was high. And the Taeyang was excepted.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.6
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• pp.57-66
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• 2011

This study researched those universities for which fence opening and greening projects are being conducted by Seoul city. The forms of opened fences at 24 universities which have accomplished this project were classified into several types for each type of university, representative cases with many diverse facilities and active users were selected and investigated. The study was carried out using methods of field observations, literature review, and surveys. To maintain the confidentiality of the collected questionnaire analysis, the analysis of each type's usage frequency, overall satisfaction and a regression analysis with space environment and facilities, a one-way ANOVA for was used to validate the difference between types regarding satisfaction with the project. The results of usage type analysis were found to agree with the 3 analysis criteria-- installation location, user characteristics, and usage purpose--which were the legislative concepts. In overall satisfaction with facilities, it appeared that except for Seoul Women's College of Nursing with its rural district neighborhood type park, users were satisfied: with the small urban neighborhood park of Methodist Theological College, Konkuk University's small urban square park, and Sejong University's green space small city park. In general, users appeared to not have satisfaction with such features as fountains / hydroponic facilities, fitness facilities, and square facilities, which should be taken into consideration when pursuing further opening and greening projects. Regarding full satisfaction with the space environment, it was found that users were not satisfied with Seoul Women's College of Nursing's rural district neighborhood-style park, whereas they were satisfied with Methodist Theological College's small urban neighborhood park, Konkuk University's small urban square-style park, and Sejong University's green space small city park. In addition, it was shown that facilities use, convenience and privacy of the four parks were largely unsatisfactory for users, and that the small city parks located at roadsides were unsatisfactory regarding noise level, both of which should be most highly considered when conducting similar projects in the future.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.6
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• pp.62-75
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• 2017

This study analyzes the multiple effects of the following three aspects of waterscape facilities within apartment complexes: planning/designing, maintenance/management, and use of the facilities and suggests primary documents that will be fundamental for the methods to accelerate the implementation of waterscape facilities. A survey and analysis was conducted among a few of the most representative private apartment complexes in Seoul in accordance with the management and operation of waterscape facilities. The analysis used frequency analysis, descriptive statistics, reliability test, t-test, and PLS regression analysis. The research findings are as follows: first, the degree of use of waterscape facilities was found to be low regardless of the levels of operation, but residents' preference for the facilities was shown to be high, thus indicating there are still high expectations on the part of residents. Second, regardless of whether the facilities are being operated efficiently, the two items of location and display method under the section of planning and designing and the two items of aptitude and convenience under the section of use were found to positively affect the operation and use of waterscape facilities. Particularly, the item of freshness, cleanliness was shown to be directly and indirectly correlated with obsolescence, administration costs, and noise, which negatively affect the operation. Third, it was found that the administration costs itself that had been shown as the most negative factor of operating landscaping facilities in previous research did not cause problems in the residential area where the facilities are not operated efficiently. The finding suggests that the administration costs do not matter but that in the case of experience- and entertainment-typed facilities that residents want, they are linked to problems that do not introduce the desired facilities. Fourth, it was found that various aspects of planning, designing, maintaining, and using facilities interconnect and affect one another in the process of operating and using waterscape facilities resulting in the need to have a comprehensive approach to these three factors of planning, design, maintenance, management, and utilization. This study proposes that the needs and values of residents should be reflected to activate the introduction of landscaping facilities in the apartment complexes.

• Journal of Korean Society of Transportation
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• v.22 no.6
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• pp.133-144
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• 2004

A model and a measure which can evaluate the risk of rear end collision are developed. Most traffic accidents involve multiple causes such as the human factor, the vehicle factor, and the highway element at any given time. Thus, these factors should be considered in analyzing the risk of an accident and in developing safety models. Although most risky situations and accidents on the roads result from the poor response of a driver to various stimuli, many researchers have modeled the risk or accident by analyzing only the stimuli without considering the response of a driver. Hence, the reliabilities of those models turned out to be low. Thus in developing the model behaviors of a driver, such as reaction time and deceleration rate, are considered. In the past, most studies tried to analyze the relationships between a risk and an accident directly but they, due to the difficulty of finding out the directional relationships between these factors, developed a model by considering these factors, developed a model by considering indirect factors such as volume, speed, etc. However, if the relationships between risk and accidents are looked into in detail, it can be seen that they are linked by the behaviors of a driver, and depending on drivers the risk as it is on the road-vehicle system may be ignored or call drivers' attention. Therefore, an accident depends on how a driver handles risk, so that the more related risk to and accident occurrence is not the risk itself but the risk responded by a driver. Thus, in this study, the behaviors of a driver are considered in the model and to reflect these behaviors three concepts related to accidents are introduced. And safe stopping distance and accident occurrence probability were used for better understanding and for more reliable modeling of the risk. The index which can represent the risk is also developed based on measures used in evaluating noise level, and for the risk comparison between various situations, the equivalent risk level, considering the intensity and duration time, is developed by means of the weighted average. Validation is performed with field surveys on the expressway of Seoul, and the test vehicle was made to collect the traffic flow data, such as deceleration rate, speed and spacing. Based on this data, the risk by section, lane and traffic flow conditions are evaluated and compared with the accident data and traffic conditions. The evaluated risk level corresponds closely to the patterns of actual traffic conditions and counts of accident. The model and the method developed in this study can be applied to various fields, such as safety test of traffic flow, establishment of operation & management strategy for reliable traffic flow, and the safety test for the control algorithm in the advanced safety vehicles and many others.

• Journal of the Korean Society of International Agriculture
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• v.30 no.4
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• pp.292-299
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• 2018

In a survey in which farmers were asked about their levels of satisfaction with agricultural machines, Japanese products scored higher than local products by 1.2, 1.3, and 1.4 times for tractors, combine harvesters, and rice transplanter, respectively. Japanese products corresponded to generally high satisfaction levels in terms of operating performance, operability, frequency of breakdowns, and durability, excluding sales price and after-sales services. Effective countermeasures through quality improvement are therefore necessary for Korean products. Furthermore, a survey of dealers showed that the components and consumables for core agricultural machines had high frequencies of breakdowns and repairs. Four major components of tractors represented 85.3% of all breakdowns and repairs, five components of combine harvesters represented 89.6%, and three components of rice transplanters represented 80.5%. Moreover, a comparison of the technological levels between local and imported machines showed that the local machines' levels were at 60-100% for tractors, 70-100% for combine harvesters, and 70-95% for rice transplanters. Small and mid-sized tractors, 4 interrow combine harvesters, and 6 interrow rice transplanters showed similar levels of technology. The results of the analysis suggest that action is urgently needed at a policy level to establish an agricultural machinery component research center for the development, production, and supply of commonly-used components, with the participation of manufacturers of agricultural machines and components, in order to enhance the competitiveness of local manufacturers and to revitalize the agricultural machine market.