• Journal of radiological science and technology
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• v.42 no.6
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• pp.455-460
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• 2019

This study compared the radiation transmission and image quality of polymethylmethacrylate (PMMA), polycarbonate (PC), and carbon, which are common components of the compression plates currently used during breast imaging. In addition to measuring the transmitted dose and the intensity without the use of a compression paddle, the four different compression paddles were evaluated according to the material and thickness of each paddle. Radiation transmittance, maximum intensity, and plot profile type w ere all evaluated for each material, and for each factor evaluated the follow ing order w as noted, from best to w orst: carbon 4 mm, PMMA 3 mm, PMMA 4 mm, and PC 4 mm. It is necessary to study a variety of materials and thicknesses in order to find the optimal combination of material and thickness, because not only does the material have a large influence in reducing the radiation exposure during mammography, but the thickness of the compression plate also has a great influence.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.296-299
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• 2006

This study is about correlation between WECPNL and other units such as NNI, Leq and Ldn for aircraft noise that ere measured by automatic measuring system networks for grasping the effect of aircraft noise and investigated the aircraft noise level from 2004 to 2005 nearby 10 airports in Korea. It is very important to find the relationship among the various noise units, because exchange between the results of many other nation's study can improve the assessment and mitigation study of the aircraft noise. Correlation between WECPNL and M is better than one between WECPNL and Leq and between WECPNL and Ldn, because WECPNL and NNI are based on the PNL.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.333-341
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• 1998

The general method of structural analysis for building structures has been based upon the assumption that all dead loads are imposed on a building simultaneously throughout the entire structure. In reality, buildings are built floor by floor or a few floors at a time. The construction dead load is applied gradually onto the structure as the structure is being erected. The prevailing commercial software for structural analysis used to date have resulted in the representation of inaccurate structural behaviors. The actual construction sequence and the loading of the structure ere not properly represented in the analysis. This paper identifies the source of the errors and develops the algorithm to account for the differential column shortening due to construction dead load based upon a given construction sequence

• The Research Journal of the Costume Culture
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• v.3 no.1
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• pp.65-82
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• 1995

The purpose of this research is to grasp the factors behind a mother's behavior in purchasing baby's clothes and to investigate how her purchasing behavior is affected by the baby's age, sex, rank, her age, her educational background, her place of residence, her occupation, the number of children's and family's monthly income. for this purpose, questionnaires were used and personal interviews with 481 mothers who bring up from newborns to two-year-old babies in Seoul ere conducted. Through this research, some facts have been found as follows. 1. Mother's behavior in purchasing baby's clothes are affected by baby's variables such as the baby's age, sex and rank, particularly it is much affected by baby's rank. 2. Mother's behavior in purchasing baby's cloths are affected by mother's variables such as the mother's age, educational background, place of residence, occupation, the number of children's and family's monthly income. Particularly it is much affected by mother's educational background and family's monthly income.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.14 no.1_2
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• pp.89-96
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• 1992

The purpose of this study was to investigate the fractures of facial skeleton ; mandible, maxilla, zygoma Clinically, we observed 413 patients with facial bone fractures treated at the department of dentistry, Koryo General Hospital from Jan. l989 to Dec. I991. This results ere as follows : 1. The most common fracture was occured in the mandible (63.7%) and the symphysis was occured most freguently(30.4%) 2. The most prevalent age was twenties(37.5%) 3. Main causes was traffic accident(21.7% ) 4. The ratio of male to female was about 9.3 : 1 5. Most combined injuries was head injuries. (54.6%) 6. The most frequent job was a company employee. 7. There were the highest frequency in March, and the lowest frequency in February.

• Journal of Korean Home Economics Education Association
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• v.10 no.1
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• pp.153-169
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• 1998

The purposes or this study were to develop the scientific experimental model, experimental guidelines for teachers, experiment planning & report form for students, and evaluation scales for the Home Economics Textiles class in high school. First, through review of literature concerned, scientific experimental model was defined, and the usefulness of this model on the teaching situation testified on other subjects such as Physics and Bilolgy, was reviewed. Secondly, scientific experimental model, experimental guidelines for teachers, experiment planning & report form for students, and evaluation scale were developer on the bases on APU evaluation model, experimental guidelines for teachers, experiment planning & report form for students, evaluation scale applicable to the teaching situation ere established by analysing the significant differences scientifically.

• Korean Journal of Health Education and Promotion
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• v.17 no.2
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• pp.35-56
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• 2000

This study is research on physical health and mental health(physical and mental symptom at school) in perceived school environment among adolescents. The study subjects ere selected by senior high school students in seoul and random sampling. The 3,060 subjects were selected 18 schools. The duration for survey was for Nov. 25-Dec. 13, 1998. The reliability of Questionnaire was Cronbach's $\alpha=0.95$. This study used multiple regression through Factor Analysis in SPSS programs. The major findings of this study are as follows: (1) All of Multiple Regression Models were significant. (p<0.001). (2) Physical Mental health is related to gender, personal environment, and economic status. (3) Physical Health is related to perceived school environmental variable (therapeutic teacher-student relationships, classrom climate, and school life satisfaction) among adolescents. (4) Mental Health is related to perceived school environment variables(therapeutic teacher-student relationships, classroom climate, school life satisfaction, teachers' climate, and classmates' attitudes) among adolescents. This study could be used as the basis for the development of educational program, counseling, teacher in-service training, student teacher training and the establishment of educational and health policy.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.163-164
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• 2017

The paper is to investigate the effect of spreading of various kinds of oils on resistance to chloride attack of the normal strength concrete. Resistance to chloride attack was measured for 32 weeks and six different kinds of oils ere used. Test results indicated that resistance to chloride attack was improved in order of DSP, BD, ERBD and ERCO compared with that of Plain mixture due to filling effect of capillary pore by the use of oil.

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.244-247
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• 1993

In this paper, Fuzzy-Neural Network Control system that has the characteristic of fuzzy control to be controlled easily end the good characteristic of a artificial neural network to control the plant due to its learning is presented. A fuzzy rule to be applied is selected automatically by the allocated neurons. The neurons correspond to Fuzzy rules which ere created by a expert. To adaptivity, the more precise modeling is implemented by error beck-propagation learning of adjusting the link-weight of fuzzy membership function in Fuzzy-Neural Network. The more classified fuzzy rule is used to include the property of Dual Mode Method. To test the effectiveness of the algorithm presented above, the simulation for position end velocity of DC servo motor is implemented.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05b
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• pp.404-407
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• 2004

The radio communication technology has been developed keeping pace with recent information ere. As the personal desire of information is activated highly efficient computers come out. Therefore the network using LAN has set up. This paper about antenna available in wireless LAM of 5GHz band Which is compareatively easy therefore designing in antenna having broa㏈and and analyzing it throuth transmission-line model.