• Advances in nano research
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• v.2 no.3
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• pp.157-172
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• 2014

The three-dimensional Nano-Electronic Modeling toolkit (NEMO 3-D) is an open source software package that allows the atomistic calculation of single-particle electronic states and optical response of various semiconductor structures including bulk materials, quantum dots, impurities, quantum wires, quantum wells and nanocrystals containing millions of atoms. This paper, first, describes a software module introduced in the NEMO 3-D toolkit for the calculation of electronic bandstructure and interband optical transitions in nanowires having wurtzite crystal symmetry. The energetics (Hamiltonian) of the quantum system under study is described via the tight-binding (TB) formalism (including $sp^3$, $sp^3s^*$ and $sp^3d^5s^*$ models as appropriate). Emphasis has been given in the treatment of surface atoms that, if left unpassivated, can lead to the creation of energy states within the bandgap of the sample. Furthermore, the developed software has been validated via the calculation of: a) modulation of the energy bandgap and the effective masses in [0001] oriented wurtzite nanowires as compared to the experimentally reported values in bulk structures, and b) the localization of wavefunctions and the optical anisotropy in GaN/AlN disk-in-wire nanowires.

• Composites Research
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• v.16 no.4
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• pp.59-65
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• 2003

FEM analysis of the smart skin structure, and application of the sandwich structures investigated. The honeycomb manufactures only provide stillness of thickness direction and transverse shear modulus. Although these are dominant mechanical properties. the other mechanical properties are needed in FEM analysis. Hence, this work shows procedures of obtaining those mechanical properties. Honeycomb material was assumed to be ar, isotropic material and properties are estimated by its dominant honeycomb properties. The other honeycomb properties are then obtained by mechanical properties of Nomex. Buckling test and three point bending test were simulated by ABAQUS. Both the shell and solid element models were used. The results were compared with experimental results and analytical approaches. They showed good agreements. This study shows a guideline of FEM analysis of smart skin structure using commercial a FEM package.

• Transactions of Materials Processing
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• v.14 no.8 s.80
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• pp.675-680
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• 2005

This study was aimed at the design of the dies for the automobile part for the engine oil leakage prevention using the computer simulation to shorten the period of production, on the basis of the process planning which was designed by the field experts. In the computer simulation,'eesy-2-form' of 2D FEM simulation package and 'eesy-DieOpt' have been used, which are the commercial process analysis and die design program. Through the simulation of 'eesy-2-form', we could know the propriety of the forming process, the inner pressure of the die and the suitable fitting pressure between the insert and the sleeve which was not showing any positive tangential stresses in the insert. Through the simulation of 'eesy-DieOpt', we could know the number of the stress ring, the diameter ratios, the stresses of the die, the shrink fitting tolerance and temperature in the condition of the already determined maximum outer die diameter of the multi-stage former. The validity of the die design using the computer simulation was analyzed by the experiments and the results were satisfactory. As the results of this study, the new and easy die design system for cold forging has been developed.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.2
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• pp.136-142
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• 2015

The shell and tube heat exchanger is an essential part of a power plant for recovering transfer heat between the feed water of a boiler and the wasted heat. The baffles are also an important element inside the heat exchanger. Internal materials influence the flow pattern in the bed. The influence of baffles in the velocity profiles was observed using a three-dimensional PIV (Particle Image Velocimetry) around baffles in a horizontal circular tube. The velocity of the particles was measured before the baffle and between them in the test tube. Results show that the velocity vectors near the front baffle flow along the vertical wall, and then concentrate on the upper opening of the front baffle. The velocity profiles circulate in the front and rear baffle. These profiles are related to the Reynolds number (Re) or the flow intensity. Velocity profiles at lower Re number showed complicated mixing to obtain the velocities and concentrate on the lower opening of the rear baffle as front wall. Numerical simulations were performed to investigate the effects of the baffle and obtain the velocity profiles between the two baffles. In this study, a commercial CFD package, Fluent 6.3.21 with the turbulent flow modeling, k-${\epsilon}$ are adopted. The path line and local axial velocities are calculated between two baffles using this program.

• Journal of Elementary Mathematics Education in Korea
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• v.19 no.2
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• pp.143-158
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• 2015

This research was conducted with focus groups interviews targeted at elementary teacher to analyze perceptions on storytelling based mathematics textbooks. As a result, elementary school teacher recognizes the introduction of storytelling as a major change in the revised textbooks. In addition, a change in the appearance of the revised textbook, the role of the Materials package, a change of assessment items, and increased exploration activity and the experience turned out to be having a significant impact on actual classroom as much as the introduction of storytelling.

• Journal of Korea Multimedia Society
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• v.8 no.1
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• pp.88-100
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• 2005

In computer graphics, realistic skin rendering has been regarded as difficult tasks and remains as an important research subject. Translucent materials like skin have some complicated optical properties including subsurface scattering. In this paper, we proposes a skin shader based on subsurface scattering to render realistic skin and it has been implemented as a plug-in for Maya, 3D Package. The rendered image using this proposed skin shader appears more realistic than the rendered image using classical shading techniques. Furthermore, we could model sebum, epidermis, dermis using specular reflection, multiple scattering, single scattering respectively.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.2
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• pp.401-406
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• 2015

Background: This study was planned as comparative and descriptive in order to measure and evaluate the knowledge and attitudes regarding early diagnosis of women with and without a family history of cervical cancer. Materials and Methods: The study sample consisted of the relatives of female patients (N=253) who were admitted to Istanbul University of Medicine. Women with a family history of cervical cancer formed the case group, while those without family history of cervical cancer constituted the control group. Two distinct data collection tools, a questionnaire and the Miller Behavioral Style Scale (MBSS), were used in order to obtain data for evaluation with SPSS for Windows 20.0 statistics package program. Results: It was found that 61.0% of the case group with family history of cervical cancer and 19.0% of the control group without family history of cervical cancer were using early diagnostic methods. Thus the presence of an individual with cervical cancer in the family affected the attitudes towards early diagnosis. It was further found that the level of knowledge on cervical cancer and PAP smear test was higher in the case group, which was more sensitive with regard to being informed about cervical cancer as compared to general society. However, the average MBSS scores were not significantly different compared to the control group. Conclusions: It was noted that, women participating this study knowledgeable, but this did not necessarily transform into better behavior.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.2085-2089
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• 2013

Background: The purpose of this descriptive study was to investigate attitudes women of towards cervical cancer prevention applications and early diagnosis, and whether or not their hopelessness levels had any influence. Materials and Methods: The present study was carried out in Isparta with a descriptive design. A sample of 251 individuals was recruited from January 2011 through May 2011 in the largest tea garden (restaurant-cafe). The data collection tool consisted of two parts: a "Questionnaire Form" identifying women; and the "Beck Hopelessness Scale". Data were analyzed using the Statistical Package for the Social Sciences (SPSS version 16.0 for Windows for the numerical and percentage distribution, average, standard deviation with the ANOVA and Mann-Whitney tests. Results: Some 70.2 % of the woman indicated that they had not taken the Pap test. There was a significant relationship between the hopelessness level and women believing that they could protect themselves from getting cervical cancer (F=10.11 p=0.00). There was a significant relationship between hopelessness levels and believing whether or not early diagnosis tests are deterministic (F=8.781 p=0.00). Conclusion: Our study concluded that the hopelessness level of women had an effect on their thoughts about cervical cancer prevention and early diagnosis.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.1
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• pp.29-35
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• 2015

In this study, a FEM analysis is undertaken of a rubber sleeve which is mounted onto a spreading mandrel so as to avoid marking the first wrappings of coils (known as the 'end-mark'), as occasionally occurs when a concentrated load is placed on the edge of a steel sheet, significantly reducing its quality. A commercial numerical package, ANSYS, was utilized to analyze the structural behavior of the rubber sleeve. In general, the strain of the sleeve increases as the thickness of the rubber layer (H) covering the tubes increases, thus also increasing the surface of the sleeve for a constant boundary condition, and decreasing the pitch (P) between each tube, resulting in an increase in the strain on the surface of the sleeve for all rubber thickness conditions tested here. In a comparison of two different materials, rubber and urethane, when H=3 mm and P=1.1D, the maximum total deformations in these cases are 0.12669 mm and 0.086623 mm, respectively.

• Journal of Korean Academy of Nursing
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• v.12 no.2
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• pp.91-104
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• 1982

This study on stressful life events and coping methods of medical patients and community people was applied to people who was divided into two groups from July 19 to Aug. 7, 1982, One is hospitalized patients in medical wards of two university hospitals in Seoul. The other is inhibitants in eight Dongs of Seoul. This study compared the number and seversity of stressful life events reported by medical patients and community people within last six months, identified coping methods used by the two groups and explored the relationship between stressful life events and coping methods. Two instruments are used in this study. The first one to measure stressful life events, is Holmes ＆ Rahe(1967)'s S.R.R.S.(Soual Readjustment Rating Scale), which is translated ＆ amended, So that it consists of 51 items. The second one is for evaluating coping method. It consists of 36 items amended through preliminary test after consideration of related literature review and survey on the basis of Bell(1877)’s‘18-item-Questionnaire.’The materials were analyzed by S.P.S.S. (Statistical Package for the Social Science) program. The results of analysis were as follows: 1. There were no significant difference in the number and severity of stressful life events reported by medical patients and community people (p>.05). 2. There were no significant difference in use of coping methods (p>.05). 3. Stressful life events showed a positive correlation with coping methods (r=.363).