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A Study on Shoes for Culinarian Use in the Kitchen Environment (조리 환경에 적합한 기능성 신발(조리화)에 관한 연구)

  • Oh, Suk-Tae
    • Culinary science and hospitality research
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    • v.15 no.1
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    • pp.296-308
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    • 2009
  • According to Lee In-ja's research into the cooks of Korea, there are more than 1.2 million culinary professionals in Korea. However, it is hard to find studies on their work environment. From this point, this study aims to examine the shoes worn by culinarians in their workplace and facilitate the improved environment to protect culinary professionals against potential dangers such as slips, occupational and industrial injuries and fatigue, on the basis of the shoes they wear. The research was conducted on a representative cross section of safety shoes currently worn by culinary professionals. The four factors to be tested and measured for the study were weight, slip resistance, internal tearing strength and splitting resistance. Findings on inquiry showed that the shoes tested were quite heavy, slippery and readily liable to splitting under low stress - when compared to standardized base figures. In accordance with the results of this experiment, guidelines for four factors of manufacture were suggested. First, chef's shoes should weigh not more than 1% of a wearers weight. Second, they should exhibit more than 0.50 $\mu$ slip resistance. Third, they should withstand at least 50.0 N/mm tearing strength. And finally, they should have upwards of 3.0 kg/cm splitting resistance.

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Fatigue fracture of different dental implant system under cyclic loading (반복하중에 따른 수종 임플란트의 피로파절에 관한 연구)

  • Park, Won-Ju;Cho, In-Ho
    • The Journal of Korean Academy of Prosthodontics
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    • v.47 no.4
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    • pp.424-434
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    • 2009
  • Statement of problem: Problems such as loosening and fractures of retained screws and fracture of implant fixture have been frequently reported in implant prosthesis. Purpose: Implant has weak mechanical properties against lateral loading compared to vertical occlusal loading, and therefore, stress analysis of implant fixture depending on its material and geometric features is needed. Material and methods: Total 28 of external hexed implants were divided into 7 of 4 groups; Group A (3i, FULL $OSSEOTITE^{(R)}$Implant), Group B (Nobelbiocare, $Br{\aa}nemark$ $System^{(R)}$Mk III Groovy RP), Group C (Neobiotec, $SinusQuick^{TM}$ EB), Group D (Osstem, US-II). The type III gold alloy prostheses were fabricated using adequate UCLA gold abutments. Fixture, abutment screw, and abutment were connected and cross-sectioned vertically. Hardness test was conducted using MXT-$\alpha$. For fatigue fracture test, with MTS 810, the specimens were loaded to the extent of 60-600 N until fracture occurred. The fracture pattern of abutment screw and fixture was observed under scanning electron microscope. A comparative study of stress distribution and fracture area of abutment screw and fixture was carried out through finite element analysis Results: 1. In Vicker's hardness test of abutment screw, the highest value was measured in group A and lowest value was measured in group D. 2. In all implant groups, implant fixture fractures occurred mainly at the 3-4th fixture thread valley where tensile stress was concentrated. When the fatigue life was compared, significant difference was found between the group A, B, C and D (P<.05). 3. The fracture patterns of group B and group D showed complex failure type, a fracture behavior including transverse and longitudinal failure patterns in both fixture and abutment screw. In Group A and C, however, the transverse failure of fixture was only observed. 4. The finite element analysis infers that a fatigue crack started at the fixture surface. Conclusion: The maximum tensile stress was found in the implant fixture at the level of cortical bone. The fatigue fracture occurred when the dead space of implant fixture coincides with jig surface where the maximum tensile stress was generated. To increase implant durability, prevention of surrounding bone resorption is important. However, if the bone resorption progresses to the level of dead space, the frequency of implant fracture would increase. Thus, proper management is needed.

Effect of Trypsin on Physico-dynamic and Histological Changes after Decellularization of Bovine Pericardium (소 심낭의 무세포화에서 트립신이 이식편의 물리-역학적 및 조직학적 변화에 미치는 영향)

  • Seong, Yang-Won;Kim, Yong-Jin;Kim, Sao-Hwan;Min, Byoung-Ju;Lee, Young-Ok;Lim, Hong-Gook
    • Journal of Chest Surgery
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    • v.43 no.6
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    • pp.565-575
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    • 2010
  • Background: Various decellularization methods have been studied in order to develop tissue graft which is less immunogenic and more durable. This study was performed to investigate the physico-dynamic and histological effect of trypsin pretreatment on decellularization protocols. Material and Method: Two groups of bovine pericardium specimen each underwent decellularization process based on SDS and Triton X-100 or N-lauroylsarcosinate and Triton X-100. Two more groups additionally underwent pretreatment with 0.1% Trypsin/0.1% EDTA. After decellularization process, mechanical tensile strength was tested, then biomechanical test of permeability and compliance was tested before and after fatigue test. Light microscopy and electron microscopy was performed to observe histological findings. Result: There was no difference in mechanical tensile strength between groups, but permeability and compliance was decreased in trypsin pretreated groups. Light microscopic and electron microscopic findings revealed damage of the extracellular matrix in trypsin pretreated groups and in groups which underwent the fatigue test also. Conclusion: Trypsin pretreatment in decellularizing process of bovine pericardium damages extracellular matrix and increases permeability and compliance of the bovine pericardium, but did not decrease tensile strength. Further studies are needed to use enzymatic treatments in decellularization protocols.

A Survey on the Meal Management Attitudes of Housewives Who Had Elementary Schoolchildren in a Remote Rural Country in Korea (일부 벽지 농촌 가정 주부의 식생활 관리 실태 조사)

  • Kim, Jin-Yang;Kim, Sun-Hyo
    • Journal of the Korean Society of Food Culture
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    • v.20 no.2
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    • pp.131-143
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    • 2005
  • This study is performed to examine the meal management attitudes of housewives who had elementary schoolchildren in the remote rural areas(RA: n = 318, $37.2{\pm}0.3$ years of age) in comparison to those in their vicinity urban area(UA: n = 349, $36.9{\pm}0.2$ years of age) in the Chungnam province in Korea. The subjects were asked to fill out the questionnaire on their attitudes of meal management for their families. The results obtained in this study were as followings: (1) Most husbands of the subjects had a farming job in the RA while they had salaried workers in the UA(p<0.001). Education levels of both subjects and their husbands were lower in the RA than in the UA. Nuclear families were dominated by both groups, however single parent-family and step parent-family were more prevalent in the RA than in the UA. (2) in terms of ways of getting foods such as grains, meats, eggs, vegetables and fruits, the RA housewives relied more often on self-production than did the UA housewives(p<0.001). (3) The frequency of purchasing unprocessed foods was lower in the RA than in the UA(p<0.001). The RA housewives purchased the convenient foods such as instant noodles(p<0.05), ready to eatsoups(p<0.001), retort pouch foods(p<0.05) and instant teas(p<0.05) more frequently than did the UA housewives, while tuna, canned in oil(p<0.01), milk and their products(p<0.001), soybean products(p<0.001) and snacks(p<0.01) were purchased less often by the RA housewives. (4) Family members except housewives engaged more often in meal preparation in the RA than did those in the UA(p<0.001), which was more strongly observed for dinner. The time spent in preparing the dinner was shorter in the RA than in the UA(p<0.001). (5) The degrees of endeavor to provide the subjects' offspring with balanced meal(p<0.001) and nutrition education(p<0.01) were lower in the RA than in the UA. The RA housewives had more difficulty for performing meal management because of 'over work-related fatigue', 'insufficient money to purchase foods' and 'far distance from grocery' than the UA housewives(p<0.001). The RA housewives had lower score on nutritional knowledge(p<0.001) and wanted more strongly nutritional knowledge to improve the quality of family's meal than did the UA housewives(p<0.01). Therefore, the RA housewives had various problems regarding meal management such as 'over work related to fatigue', 'food-purchasing inconvenience', 'low economic status of family' and 'lack of nutritional knowledge'. As a consequence the RA housewives relied on cheap convenient foods more often in order to prepare the meal easily than did the UA housewives. These findings emphasize the need in the RA for nutrition education for housewives and a range of nutrition policies that focus upon the social and economic determinants of food choice within families to improve the nutritional status of the RA residents.

A Review of Studies Comparing of Surface Electromyography Values between the Low-back Pain Group and Healthy Controls (요통환자군과 정상대조군 사이의 표면근전도값 비교에 관한 연구문헌 고찰)

  • Yoo, Duk-Joo;Cho, Jae-Heung;Chung, Seok-Hee
    • Journal of Korean Medicine Rehabilitation
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    • v.23 no.4
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    • pp.83-93
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    • 2013
  • Objectives To present reviews of studies comparing surface-electromyography (SEMG) values between low back pain group and control group. Methods We searched 8 databases including KoreaMed, Google, KISS (Korean studies Information Service System), RISS (Research Information Sharing Service), OASIS (Oriental medicine Advanced Searching Integrated System), Pubmed, Ovid-MEDLINE and EMBASE. After searching, we conducted study selection by using inclusion and exclusion criteria and quality-assessment. We reviewed the selected studies concerning about the subject's measuring position, findings, sensitivities and specificities. Results 27 Studies were searched and reviewed. In static surface electromyography, more muscle activities observed in low back pain subjects than in controls. In dynamic surface electromyography, the low back pain subjects showed more muscle activites during flexion, while the control group showed more muscle activities during extension. Faster muscle fatigue observed in isometric muscle analysis. Conclusions Surface electromyography values will be able to be objective marker for evaluating low back pain. Further research is needed to determine additional unified protocol such as the type of SEMG and its directions.

Studies on the Efficacy of Combined Preparation of Crude Drug (III) -Fundamental Research for the Pharmacological Activity of 'Kangsim-San'- (생약복합제제(生藥複合製劑)의 약효연구(藥效硏究) (제3보)(第3報) -강심산(强心散)의 기초약물학적(基礎藥物學的) 활성(活性)에 대(對)하여-)

  • Hong, N.D.;Kim, J.W.;Cheong, J.H.;Choi, S.G.
    • Korean Journal of Pharmacognosy
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    • v.12 no.4
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    • pp.195-199
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    • 1981
  • 'Kangsim-San' is an added and subtracted prescription of 'Cheongsim-Yeonza-Tang' recorded in 'Dongeuy-Soose-Boweon' from which it has become one of the favorate prescriptions at the Oriental Medical Hospital, Kyung-Hee University. It is described in the book that the 'Cheongsim-Yeonza-Tang' can be effective to symptoms relating to fatigue, nocturnal emission, abdominal pain, tongue deviation and palsy, etc. However the 'Kangsim-San' has been used for neurotic syndrome, pulpitation, insomnia, constipation, dry-mouth, auorexia and arrythmias and so on, added to the above-mentioned symptoms for the 'Cheongsim-Yeonza-Tang' at the hospital. Nevertheless, the pharmacological research of fundamental basis is not completed so far, and we have attempted experiment on various animals to study the pharmacological effects of the medicine. The result was proved as follows; The prescription had a considerable effects on the sedation of central nervous system, antipyretic and analgesic action, and vasodilative action.

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Root Cause Analysis on the Steam Turbine Blade Damage of the Combined Cycle Power Plant (복합화력발전소 증기터빈 동익 손상 원인분석)

  • Kang, M.S.;Kim, K.Y.;Yun, W.N.;Lee, W.K.
    • Journal of Power System Engineering
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    • v.12 no.4
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    • pp.57-63
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    • 2008
  • The last stage blade of the low pressure steam turbine remarkably affects turbine plant performance and availability Turbine manufacturers are continuously developing the low pressure last stage blades using the latest technology in order to achieve higher reliability and improved efficiency. They tend to lengthen the last stage blade and apply shrouds at the blades to enhance turbine efficiency. The long blades increase the blade tip circumferential speed and water droplet erosion at shroud is anticipated. Parts of integral shrouds of the last stage 40 inch blades were cracked and liberated recently in a combined cycle power plant. In order to analyze the root cause of the last stage blades shroud cracks, we investigated operational history, heat balance diagram, damaged blades shape, fractured surface of damaged blades, microstructure examination and design data, etc. Root causes were analyzed as the improper material and design of the blade. Notches induced by erosion and blade shroud were failed eventually by high cycle fatigue. This paper describes the root cause analysis and countermeasures for the steam turbine last stage blade shroud cracks of the combined cycle power plant.

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The review of factors of pressure sores associated with a wheelchair seating (휠체어 착석과 욕창 발생 관련 요인의 고찰)

  • Jeong Dong-Hoon;Kong Jin-Yong;Kwon Hyuk-Cheol
    • The Journal of Korean Physical Therapy
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    • v.12 no.2
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    • pp.229-238
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    • 2000
  • A properly prescribed wheelchair may be able to normalize tone. decrease pathologic reflex activity, improve postural symmetry, enhance range of movement, maintain and/or improve skin conduit)n. increase comfort and sitting tolerance, decrease fatigue, and improve function of the autonomic nervous system. Whereas a poorly prescribed one can actually exacerbate the problems associated with a disability. Maintained for longer without relief, pressure concentrations may also lead to tissue breakdown. Pressure sores continue to be a major problem for many disabled individuals. Many groups of disabled individuals have a very high incidence of pressure sores, including those individuals with spinal cord injuries. hemiplegia, multiple sclerosis. cancer. and the disabled geriatric population. It is important to understand the factors which predispose an individuals to the development of a pressure sores. Those factors can divided into extrinsic factors, related to the individual's immediate environment and intrinsic factors. related to their medical or physical condition. Pressure sores are generally preventable through sensible pressure management based on an understanding of the causes of pressure sores, risk factors and methods of redistributing pressure.

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Inverse Estimation of Fatigue Life Parameter based on Bayesian Approach (베이지안 접근법을 이용한 피로수명 파라미터의 역 추정)

  • Heo, Chan-Young;An, Da-Wn;Choi, Joo-Ho;Jeon, Jeong-Il
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2010.04a
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    • pp.620-623
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    • 2010
  • 구조요소의 설계에서 유한요소해석은 매우 효과적인 방법이며 정확한 해석 기술을 요구한다. 그러나 제조 공정이나 환경에 따라 달라지는 재료 물성이나 불확실성을 내포하는 피로 물성을 확정적인 값으로 이용하는 등 입력 변수의 부정확한 정보로 인해 유한요소해석 결과를 신뢰하지 못하는 경우가 자주 발생한다. 실제 시험을 통해 설계의 결과를 예측하는 것은 경제적인 측면과 시간소요 면에서 한계가 따르기에 신뢰할 수 있는 유한요소해석 방법이 요구된다. 본 연구에서는 고주기의 피로 해석을 위해 유한요소해석을 이용하여 스프링의 응력-수명(S-N) 파라미터를 역 추정하고 수명을 예측해 보았다. 이를 위해 실제 산업현장에서 쓰이는 자동차 서스펜션 코일 스프링을 예제로 사용하였다. 시험 모델에 대해 불확실성을 고려한 베이지안 접근법을 이용하여 입력변수의 파라미터를 역 추정하였으며, 마코프체인몬테카를로(Markov Chain Monte Carlo) 기법을 이용하여 얻어진 피로 물성 파라미터의 샘플 데이터를 이용해서 유한요소해석을 실시하고 신뢰수준 내에서 새로운 구조요소의 피로수명을 예측하였다.

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Antioxidative and Antimutagenic Effects of the Ethanol Elrtract from Cordyceps militaris (번데기동충하초(Cordyceps militaris) 에탄을 추출물의 항산화성 및 항돌연변이원성 효과)

  • 김미남;오상화;이득식;함승시
    • Food Science and Preservation
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    • v.8 no.1
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    • pp.109-117
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    • 2001
  • Cordyceps militaris is a parasitic fungus that has been used as a Chinese medicine for the treatment of fatigue, debility, kidney disease, tuberculosis, asthma and cardiac insufficiency etc. This study was carried out to determine the antioxidative and antimutagenic effects of Cordyceps militaris using DPPH free radical donating method and Ames test, respectively. They were extracted with ethanol and then further fractionated to n-hexane, chloroform, ethyl acetate, butanol and water, stepwise. Among five fractions, the EtOAc and BuOH fractions showed the highest electron donating activities, about 2-fold higher than other fractions. In Ames test, most of the extracts had strong antimutagenic effects against the mutagenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine(MNNG), 4-nitroquinoline-1-oxide(4NQO), benzo($\alpha$)pyrene(B($\alpha$)P) and 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indol (Trp-P-1). The EtOH extracts of C. militaris (200 $\mu\textrm{g}$/plate) showed 62.8%, 74.4% and 67.2% inhibitory effects on the mutagenesis induced by 4NQO, B($\alpha$)P and Trp-P-1, respectively, against TA98 strain, whereas 78.1%, 78.6%, 78.6% and 82.7% inhibition were observed on the mutagenesis induced by MNNG, 4NQO, B($\alpha$)P and Trp-P-1, respectively, against TA100 strain. Especially, the BuOH fraction showed the highest antimutagenic effects against mutation induced by MNNG.

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