• Structural Engineering and Mechanics
• /
• 제64권4호
• /
• pp.487-494
• /
• 2017

The present paper deals with a theoretical study of delamination fracture in the Crack Lap Shear (CLS) functionally graded beam configuration. The basic purpose is to analyze the fracture with taking into account the material non-linearity. The mechanical behavior of CLS was described by using a non-linear stress-strain relation. It was assumed that the material is functionally graded along the beam height. The fracture was analyzed by applying the J-integral approach. The curvature and neutral axis coordinate of CLS beam were derived in order to solve analytically the J-integral. The non-linear solution of J-integral obtained was verified by analyzing the strain energy release rate with considering material non-linearity. The effects of material gradient, crack location along the beam height and material non-linearity on fracture behavior were evaluated. The J-integral non-linear solution derived is very suitable for parametric studies of longitudinal fracture in the CLS beam. The results obtained can be used to optimize the functionally graded beam structure with respect to the fracture performance. The analytical approach developed in the present paper contributes for the understanding of delamination fracture in functionally graded beams exhibiting material non-linearity.

• 한국식품영양학회지
• /
• 제12권3호
• /
• pp.306-311
• /
• 1999

The purpose of this study was to investigate dietary attitudes food behaviors and nutrition knowledge of food nutrition major and non-major female students. The subjects of this study consisted of 98 food and nutrition majors and 98 non-majors. Questionnaires were completed by them. Food and nutrition majors gave a serious consideration of taste and nutrition in selecting foods while non-majors considered taste food price amount of food and preparing time. Food and nutrition majors got higher scores in hig-her level of nutrition knowledge than non-majors and both got about the same scores in basic nutrition knowledge. The mean body weights of both were about the same and mean height of non-majors was hig-her than food and nutrition majors. Accrding to obesity index ideal body weight was more in food and nutrition ajors and underweight was more in non-majors. Dietary attitudes food behaviors and nu-trition knowledge of food and nutrition majors were better than those of non-majors. Therefore nutrition non-majors need nutrition education in order to improve their food behaviors and nutrition knowledge.

• Journal of Periodontal and Implant Science
• /
• 제28권1호
• /
• pp.121-131
• /
• 1998

The purpose of this study was to investigate the effects of smoking on adult periodontitis after non-surgical periodontal therapy. The study population consisted of 40 patients with moderate to advanced periodontitis. Smokers(n=20) were defined as individuals smoking at least twenty cigarettes per day at the time of the initial examination. The non-smoking group(n=20) second and the fourth weeks after periodontal non-surgical therapy. The results were as follows; 1. Clinical indices including plaque index, gingival index, and pocket depth were decreased in both smoking and non-smoking group at the first, the second, and the fourth weeks. Especially, clinical indices of non-smokers were more significantly decreased than those of smokers. 2. Non-motile rods were increaseed and motile rods were reduced at the fourth week. spirochetes were reduced significantly in the non-smoking group at the fourth week. These results suggest that smoking play a minor role in adult periodontitis after non-surgical periodontal therapy.

• 호남수학학술지
• /
• 제26권3호
• /
• pp.247-256
• /
• 2004

Buchmann and Williams[1] proposed a key exchange system making use of the properties of the maximal order of an imaginary quadratic field. $H{\ddot{u}}hnlein$ et al. [6,7] also introduced a cryptosystem with trapdoor decryption in the class group of the non-maximal imaginary quadratic order with prime conductor q. Their common techniques are based on the properties of the invertible ideals of the maximal or non-maximal orders respectively. Kim and Moon [8], however, proposed a key-exchange system and a public-key encryption scheme, based on the class semigroups of imaginary quadratic non-maximal orders. In Kim and Moon[8]'s cryptosystem, a non-invertible ideal is chosen as a generator of key-exchange ststem and their secret key is some characteristic value of the ideal on the basis of Zanardo et al.[9]'s quantity for ideal equivalence. In this paper we propose the methods for finding the non-invertible ideals corresponding to non-primitive quadratic forms and clarify the structure of the class semigroup of non-maximal order as finitely disjoint union of groups with some quantities correctly. And then we correct the misconceptions of Zanardo et al.[9] and analyze Kim and Moon[8]'s cryptosystem.

• 조명전기설비학회논문지
• /
• 제22권1호
• /
• pp.7-16
• /
• 2008

주유소 조명은 안전하고 시각적으로 흥미롭게 디자인되어야 한다. 최근 연구에는 빛공해와 에너지 낭비 때문에 non-cutoff 조명기구를 주유소에 이용되면 안 되는 것을 보여주었다. 본 연구에서는 non-cutoff 조명기구를 사용한 주유소의 조명환경을 분석하는 것을 목적으로 한다. CS-100 휘도계와 Radiant Imaging Prometric-1400을 이용하여 건물표면, 캐노피, 천정, 기둥 및 바닥면을 측정하였다. 그 결과 캐노피 조명기구의 개수가 증가할수록 건물전체 표면휘도가 증가하였으며, Non-cutoff 조명기구를 설치한 연구대상 전체 주유소는 빛공해를 유발하였다. 따라서 주유소 옥외조명에 대한 기준이 마련되어야 할 것이다.

• 경영과정보연구
• /
• 제24권
• /
• pp.73-75
• /
• 2008

The purpose of this study is to propose the human resource management strategies of non-standard workers that can contribute to accomplishing both corporate social responsibility and business purpose in efficient and effective ways. For the purpose, this researcher investigated circumstances under which Korean companies are using non-standard workers and systems related to those workers. In Korea, the Non-Standard Workers Protection Act was enacted and revised, and became effective on July 1, 2007. The main provisions of the act are as follows. First, the systems of discriminatory treatment prohibition was legally stipulated, Second, restrictions on overwork for fixed-term and part-time employees and the written statement of working conditions were compelled. Third, only 26 kinds of jobs were permitted for worker dispatch in accordance with positive list system. To achieve their business purpose, companies often use standard workers, but sometimes non-standard workers unavoidably in accordance with their business strategy. This study propose main human resource management strategies of non-standard workers such as determining the scope of jobs, strengthening legal and systematic human resource management, improving human relations, extending the grievance procedure and converting non-standard workers into standard ones.

• Advances in nano research
• /
• 제3권4호
• /
• pp.193-206
• /
• 2015

The present paper investigate the elastic buckling of chiral double-walled carbon nanotubes (DWCNTs) under axial compression. Using the non-local elasticity theory, Timoshenko beam model has been implemented. According to the governing equations of non-local theory, the analytical solution is derived and the solution for non-local critical buckling loads is obtained. The numerical results show the influence of non-local small-scale coefficient, the vibrational mode number, the chirality of carbon nanotube and aspect ratio of the (DWCNTs) on non-local critical buckling loads of the (DWCNTs). The results indicate the dependence of non-local critical buckling loads on the chirality of single-walled carbon nanotube with increase the non-local small-scale coefficient, the vibrational mode number and aspect ratio of length to diameter.

• Structural Engineering and Mechanics
• /
• 제52권5호
• /
• pp.997-1017
• /
• 2014

According to the structure characteristics of the non-uniform beam bridge, a practical model for calculating the vibration equation of the non-uniform beam bridge is given and the application scope of the model includes not only the beam bridge structure but also the non-uniform beam with added masses and elastic supports. Based on the Bernoulli-Euler beam theory, extending the application of the modal perturbation method and establishment of a semi-analytical method for solving the vibration equation of the non-uniform beam with added masses and elastic supports based is able to be made. In the modal subspace of the uniform beam with the elastic supports, the variable coefficient differential equation that describes the dynamic behavior of the non-uniform beam is converted to nonlinear algebraic equations. Extending the application of the modal perturbation method is suitable for solving the vibration equation of the simply supported and continuous non-uniform beam with its arbitrary added masses and elastic supports. The examples, that are analyzed, demonstrate the high precision and fast convergence speed of the method. Further study of the timesaving method for the dynamic characteristics of symmetrical beam and the symmetry of mode shape should be developed. Eventually, the effects of elastic supports and added masses on dynamic characteristics of the three-span non-uniform beam bridge are reported.

• Journal of Periodontal and Implant Science
• /
• 제39권1호
• /
• pp.103-108
• /
• 2009

Purpose: It is well recognized that gingival enlargement is induced by unwanted effect associated with three major drugs/drug groups - phenytoin, cyclosporine, and the calcium channel blockers. The present case report describes the effect and limitation of non-surgical treatment in gingival enlargement cases. Materials and methods: Three cases included 2 drug-influenced gingival enlargement patients and a idiopathic gingival fibromatosis patient. For the drug-influenced gingival enlargement patients, the medication was replaced with other medication. And then, all the patients were treated non-surgically. Results: Drug-influenced gingival enlargements had been reduced after non-surgical treatment and the results were well-maintained. In the idiopathic gingival fibromatosis case, non-surgical treatment resulted in only limited reduction of gingival enlargement, and surgical periodontal treatment was unavoidable. Conclusion: These case reports indicated that non-surgical periodontal treatment with change in medication was effective in the treatment of drug-influenced gingival enlargements. Non-surgical approach can be considered as the primary management to reduce the gingival enlargement. If non-surgical treatment encounters a limitation, surgical treatment should be considered.

• 한국구조물진단유지관리공학회 논문집
• /
• 제3권1호
• /
• pp.129-136
• /
• 1999

In this paper, the new non-destructive equation will be proposed and evaluated in comparison to the other foreign's non-destructive equation. Through the comparisons cores strength of mock structure with compressive strength obtained from new non-destructive equation ; rebound hammer, ultra-sonic pulse velocity and combined method, it will be analyzed about application of non-destructive equation. The results are following. The new non-destructive equations follow ; (1) $F_c=9.5R{\cdot}N+62.5$ (2) $F_c=243Vp-739$ (3) $F_c=8.1R_o+205.3V_p-802$ where, $F_c$ : Compressive Strength, $R_o$ : Rebound Number. $V_p$ : Ultra-Sonic Pulse Velocity Trough the result of mock structure test, the combined method is superior to rebound method and ultra-sonic pulse velocity method in the estimation of concrete strength. In order to apply the non-destructive equation of concrete strength to the structures, it is necessary that we should be made process study on the non-destructive equation for estimation of concrete strength in the range, time and strength of application under long-term.