• Journal of Radiation Protection and Research
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• v.23 no.1
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• pp.1-6
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• 1998

A diffusion model of radioactive liquid effluents is developed and applied for YGN NPP's site, based on the Gaussian plume type model. Due to the complexity of oceanic diffusion characteristics of YGN site, a simple and reliable statistical model based on Reg. Guide 1.113 is developed. Also, a computer code package to calculate dilution factors as a function of plant operation conditions and pathway of radioactive materials. A liquid effluents diffusion model is developed by dividing the diffusion range into two categories, i. e, a near field mixing region and a far field mixing region. In the near field, the initial mixing is affected by a buoyance force, a high initial turbulence and momentum which is characterized by a plant operation condition and environmental conditions. The far field mixing is similar to gaseous effluents diffusion. So, beyond the near field region, wellknown Gaussian plume model was adopted. A different area averages of Gaussian plume equation was taken for each radioactive exposure pathway. As a result, we can get different dilution factors for different pathways. Results shows that present dilution factors used for YGN ODCM is too much overestimated compared with dilution factors calculated with the developed model.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.7 no.4
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• pp.179-186
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• 2012

The purpose of this research is to analyze how the suicide prevention affects private soldiers' stress-coping method, problem-solving ability, depression, and idea of suicide. In order to achieve such research hypothesis, Air Force ${\bigcirc}{\bigcirc}$ Unit has previously classified 64 soldiers, who have signs of suicide, and are assorted to have suicidal symptoms by the Unit, and think that they have such symptoms and need our program. Following that, overall 16 times of suicide prevention program was carried out for them. For a statistical process of collected materials after testing the effectiveness of Korean Soldiers suicide prevention program, we practiced Frequency Analysis, Analysis of Variance, Correlation Analysis, and Paired t-test by using the statistical package program of SPSS 12.0 for Windows. In result, suicide prevention program shows positive effects upon improving stress-coping method and problem-solving ability as well as reducing depression and suicide thoughts.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.10 s.181
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• pp.2552-2559
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• 2000

Most of ferrous b.c.c weld materials have martensitic transformation during rapid cooling after welding. It is well known that volume expansion due to the phase transformation could influence on the relaxation of welding residual stress. To apply this effect practically, it is necessary to establish a numerical model which is able to estimate the effect of phase transformation on residual stress relaxation quantitatively. For this purpose, the analysis is carried out in two regions, i.e., heating and cooling, because the variation of material properties following a phase transformation in cooling is different in comparison with the case in heating, even at the same temperature. The variation of material properties following phase transformation is considered by the adjustment of specific heat and thermal expansion coefficient, and the distribution of residual stress in analysis is compared with that of experiment by previous study. In this study, simplified numerical procedures considering phase transformation, which based on a commercial finite element package was established through comparing with the experimental data of residual stress distribution by other researcher. To consider the phase transformation effect on residual stress relaxation, the transition of mechanical and thermal property such as thermal expansion coefficient and specific heat capacity was found by try and error method in this analysis. In addition to, since the transformation temperature changes by the kind and control of alloying elements, the steel with many kinds of transformation temperature were selected and the effect of transformation on stress releasement was investigated by the numerical procedures considering phase transformation.

• Journal of the Korean Society for Nondestructive Testing
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• v.19 no.5
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• pp.369-377
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• 1999

Recently, it is gradually raised necessity that thickness of thin film is measured accuracy and managed in industrial circles and medical world. Ultrasonic signal processing method is likely to become a very powerful method for NDE method of detection of microdefects and thickness measurement of thin film below the limit of ultrasonic distance resolution in the opaque materials, provides useful information that cannot be obtained by a conventional measuring system. In the present research. considering a thin film below the limit of ultrasonic distance resolution sandwiched between three substances as acoustical analysis model, demonstrated the usefulness of ultrasonic signal processing technique using information of ultrasonic frequency for NDE of measurements of thin film thickness. Accordingly, for the detection of delamination between the junction condition of boundary microdefect of thin film sandwiched between three substances the results from digital image processing.

• Korean journal of food and cookery science
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• v.27 no.1
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• pp.21-31
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• 2011

The purposes of this study were to investigate the gap in perceived importance-performance between dietitians and food service workers regarding school food service sanitation and to analyze items that should be given priority for improvement. Data were collected by 440 food service workers and 71 dietitians in Gyeongbuk province. All statistical analyses were conducted using the SAS package program (version 8.2 for Windows) for descriptive analysis, t-test, and importance-performance analysis (IPA). According to the performance analysis, there were significant differences between dietitians and food service workers in 18 out of the 20 items. In all of 18 items, the evaluated performance scores according to the food service workers were higher than those of the dietitians. In addition, the results of IPA confirmed the following areas as improvement priorities: proper hand washing of food service workers, cleanliness of trays and utensils, monitoring of temperature of refrigerated/frozen foods and quality of the food materials during inspection, proper washing and disinfection of raw vegetables and fruits and maintenance of CCP records, and control of food holding temperature and methods. In conclusion, dietitians should perform education about sanitation management items that have low perceived importance and should make a plan to improve sanitation management after understanding the gap in perceived importance-performance between dietitians and food service workers.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.1379-1383
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• 2016

Background: Basal and squamous cell carcinoma (BCC and SCC) are the most common skin cancers worldwide and distinction between the two may sometimes be very difficult in routine histopathology. The present study was aimed to evaluate a reliable diagnostic method for these cancers based on immunohistochemistry (IHC). Materials and Methods: IHC was used with antibodies to Bcl-2, CD10, CEA, and EMA biomarkers, which despite non-specificity are easily available for detection of various types of tumors in pathology sections and can be used as a panel for differentiation. In this descriptive and analytic study, paraffin-embedded blocks of 29 SCC patients and 29 BCC patients were collected and sectioned for IHC staining. The results were analyzed by the STATA (version 8) statistical package using the Chi-square test. Results: BCC patients were 100%, 75.8%, 0% and 0% positive for Bcl-2, CD10, CEA and EMA markers, respectively, and for SCC patients were 3.5%, 0%, 34.5% and 82.7% positive, respectively. Using simultaneously Bcl-2 and CD10 as positive markers, detection of BCC with 88% accuracy and 100% specificity was possible, while application of CEA and EMA positivity could detect SCC with 67% accuracy and 100% specificity. Conclusions: SCC and BCC have different immunostaining profiles; therefore, Bcl-2, CD10, CEA and EMA markers can be helpful to distinguish between them.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.1463-1467
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• 2016

Background: The incidence of breast cancer is rapidly increasing in Yemen with recent indications of constituting one-third of female cancers. The main problem in Yemen remains very late presentation of breast cancer, most of which should have been easily recognisable. Since stage of disease at diagnosis is the most important prognostic variable, early diagnosis is an important option to be considered for control of breast cancer in low resourced settings like Yemen. In the present study, we aimed at describing breast cancer knowledge, perceptions and breast self-examination (BSE) practices among a sample of Yemeni women. Materials and Methods: This cross-sectional study covered 400 women attending four reproductive health centres in Aden, Yemen through face-to-face interview using a structured questionnaire during April - July 2014. We collected data on sociodemographic characteristics, knowledge about breast cancer, and screening practices as well as respondents' perceptions based on the five sub scales of the Health Belief Model (HBM): perceived susceptibility; perceived severity; perceived barriers; perceived benefits; and self-efficacy. The response format was a five-point Likert scale. Statistical Package for Social Sciences (SPSS 20) was used for statistical analysis. Statistical significance was set at p<0.05. Logistic regression analysis was conducted with BSE as a dependent variable. Results: The mean age of women was 26.5 (S.D=5.6) years. The majority (89.0%) had never ever performed any screening. Two-thirds of respondents had poor knowledge. Perceived BSE benefits and self-efficacy and lower BSE barriers perception were significant independent predictors of BSE practice. Conclusions: Poor knowledge and inadequate BSE practices are prevailing in Yemen. The need for implementing culturally sensitive targeted education measures is mandatory in the effort to improve early detection and reduce the burden of breast cancer.

• Journal of the Microelectronics and Packaging Society
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• v.10 no.3
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• pp.73-82
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• 2003

Recently, PWB(Printed Wiring Board) has been recognized in the field of microelectronic package as core technology for designing or manufacturing. PWB is the structure stacked by several materials with different thermophysical properties, which shows the different CTEs(Coefficient or Thermal Expansions) during the fabrication process and causes a lot of defects such as warpage, shrinkage, dimension, etc. Thermal deformation of PWB is affected mainly by the volume change of solder-resist among fabrication parameters. Therefore, thermal deformation of PBGA and CSP consisting of 2 layers and 4 layers was studied with solder-resist process. When over 30% in volume fraction of solder-resist, thermal deformation of 2-layered PWB was min. 40% higher than that of 4-layered PWB because 4-layered PWB contained the layer with high toughness such as prepreg, which counterbalanced the thermal deformation of solder-resist. Otherwise, when below 30%, PWB showed similar thermal deformation without regard to layers and design.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.10
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• pp.22-28
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• 1998

Signal transmission and crosstalk of coupled bondwires buried in plastic packages are analyzed using the Method of Moments and the Fourier Transform algorithm. It is also shown that the quasi-static crosstalk model of SPICE is inappropriate for designing the high-speed plastic packages. Plastic packaging material, increasing the self and mutual capacitances, is found to be helpful for the signal transmission integrity due to the dielectric compensation effect. However, it is also observed that the plastic material increases the crosstalk due to the radiation-enhanced mutual coupling effect. By investigating the geometrical and material dependence of the pulse transmission and crosstalk, it is found that the radiation-enhanced coupling effect is significant for most of typical bondwire geometries and plastic package materials. These calculation results can be effectively used for designing plastic packages of high-speed digital IC's and monolithic RFIC's.

• Proceedings of the KWS Conference
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• 2010.05a
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• pp.74-74
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• 2010

모바일 정보통신기기를 중심으로 전자패키지의 초소형화, 고집적화를 위해 플립칩 공법의 적용이 증가되고 있는 추세이다. 플립칩 패키징 접합소재로는 솔더, ICA(Isotropic Conductive Adhesive), ACA(Anisotropic Conductive Adhesive), NCA(Non Conductive Adhesive) 등과 같은 다양한 접합소재가 사용되고 있다. 최근에는 언더필을 사용하는 플립칩 공법보다 미세피치 대응성을 위해 NCP를 이용한 플립칩 공법에 대한 요구가 증가되고 있는데, NCP의 상용화를 위해서는 공정성과 함께 신뢰성 확보가 필요하다. 본 연구에서는 LDI(LCD drive IC) 모듈을 위한 COF(Chip-on-Film) 플립칩 패키징용 NCP 포뮬레이션을 개발하고 이를 적용한 COF 패키지의 신뢰성을 조사하였다. 테스트베드는 면적 $1.2{\times}0.9mm$, 두께 $470{\mu}m$, 접속피치 $25{\mu}m$의 Au범프가 형성된 플리칩 실리콘다이와 접속패드가 Sn으로 finish된 폴리이미드 재질의 flexible 기판을 사용하였다. NCP는 에폭시 레진과 산무수물계 경화제, 이미다졸계 촉매제를 사용하여 다양하게 포뮬레이션을 하였다. DSC(Differential Scanning Calorimeter), TGA(Thermogravimetric Analysis), DEA(Dielectric Analysis) 등의 열분석장비를 이용하여 NCP의 물성과 경화거동을 확인하였으며, 본딩 후에는 보이드를 평가하고 Peel 강도를 측정하였다. 최적의 공정으로 제작된 COF 패키지에 대한 HTS (High Temperature Stress), TC (Thermal Cycling), PCT (Pressure Cooker Test)등의 신뢰성 시험을 수행한 결과 양산 적용 가능 수준의 신뢰성을 갖는 것을 확인할 수 있었다.