• 제목/요약/키워드: nut

검색결과 539건 처리시간 0.021초

산학 융합 연구를 통한 차동 기어 자동 검사 시스템의 개발 (The Development of Automatic Inspection System of Differential Driver Gear through Research Convergence of Industrial and Academia)

  • 이정익
    • 한국융합학회논문지
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    • 제9권10호
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    • pp.257-263
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    • 2018
  • 본 연구는 트랜스미션에 들어가는 부품인 차동기어에 대한 자동 검사 장비를 개발하고자 하는 것이다. 본 기술개발은 Micro Vision 자동 검사 장비와 마이크로레이저 자동 검사 장비를 사용하여 만들 것이다. 이는 작업자가 부주의하게 가공한 제품을 전수검사 단계에서 불량률 0를 만들고자 한다. 본 연구를 통해 개발된 장비를 여러 분야 사업에 적용할 것이다. 포장회사, 너트 볼트 가공업체, 정밀 반도체 상단에 인쇄를 위한 업체, SMT 업체 등 다양한 분야에 비전검사 장비를 판매하고자 한다. 본 기술개발을 통해 불량률 0를 실현하면 모기업으로부터 안정적 물량 확보, 나아가 제품 신뢰도를 바탕으로 수출을 할 수 있는 기반마련의 기회도 가능하다. 자동검사시스템을 국내 자동차 부품 가공업체에 적용할 경우 우리나라 자동차의 신뢰도 또한 크게 상승 할 것으로 생각된다.

절연링형 금속플렉시블호스(CSST)의 저항 특성 및 신뢰성 평가 (The Resistance Characteristics and Reliability Evaluation of an Insulation Ring Type of Corrugated Stainless Steel Tubing(CSST))

  • 이장우;김점식;최충석
    • 한국안전학회지
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    • 제31권6호
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    • pp.25-31
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    • 2016
  • This paper has analyzed the structure, applicable regulations and the resistance characteristics of insulation ring type of CSST (Corrugated Stainless Steel Tubing for Gas). With the flammability test conducted in accordance with KS C IEC 60811-1-1, the evaluation of insulation resistance, temperature characteristics, and reliability has been conducted. An insulation ring type CSST consists of protective coating, tube, nut, insulation ring, packing, socket, and ball valve. Connecting an insulation ring type CSST to gas tubings for gas appliance is not permitted, moreover, the product shall be installed inside a sleeve pipe in case of buried installation such as the ceiling. Damages on protective coating and tube were detected when fire was applied to the test sample with a portable torch for 60 seconds. The insulation resistance of a normal product was $49.59M{\Omega}$, while that of the product completed the flammability test reduced to $9.21M{\Omega}$. The mean insulation resistance within the confidence Interval of 95% using the mini tap program 17 was $49.59M{\Omega}$ and the mean insulation resistance within the confidence interval reduced to $9.21M{\Omega}$. In the normal distribution analysis of 95% confidence interval, the value-P of the normal product was stable at 0.075 and AD(Anderson-Darling) statistic value was turned out to be 0.063, which is very normal, and the standard deviation was analyzed as 0.2586. The value P of the product completed the flammability test resulted in 0.005, the AD was 1.355 and the standard deviation reduced to 0.07908.

Evaluating long-term relaxation of high strength bolts considering coating on slip faying surface

  • Nah, Hwan-Seon;Lee, Hyeon-Ju;Choi, Sung-Mo
    • Steel and Composite Structures
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    • 제16권6호
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    • pp.703-718
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    • 2014
  • The initial clamping forces of high strength bolts subjected to different faying surface conditions drop within 500 hours regardless of loading, any other external force or loosening of the nut. This study develops a mathematical model for relaxation confined to creep on a coated faying surface after initial clamping. The quantitative model for estimating relaxation was derived from a regression analysis for the relation between the creep strain of the coated surface and the elapsed time for 744 hours. This study establishes an expected model for estimating the relaxation of bolted joints with diverse coated surfaces. The candidate bolts are dacro-coated tension control bolts, ASTM A490 bolt, and plain tension control bolts. The test parameters were coating thickness, species of coating. As for 96, 128, 168, and $226{\mu}m$ thick inorganic zinc, when the coating thickness was increased, relaxation after the initial clamping rose to a much higher range from 10% to 18% due to creep of the coating. The amount of relaxation up to 7 days exceeded 85% of the entire relaxation. From this result, the equation for creep strain can be derived from a statistical regression analysis. Based on the acquired creep behavior, it is expected that the clamping force reflecting relaxation after the elapse of constant time can be calculated from the initial clamping force. The manufacturer's recommendation of inorganic zinc on faying surface as $75{\mu}m$, appears to be reasonable.

Tobacco (Kretek) Smoking, Betel Quid Chewing and Risk of Oral Cancer in a Selected Jakarta Population

  • Amtha, Rahmi;Razak, Ishak Abduk;Basuki, Bastaman;Roeslan, Boedi Oetomo;Gautama, Walta;Puwanto, Denny Joko;Ghani, Wan Maria Nabillah;Zain, Rosnah Binti
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권20호
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    • pp.8673-8678
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    • 2014
  • Purpose: This study aimed to determine the association between tobacco consumption (kretek) and betel quid chewing with oral cancer risk. Materials and Methods: A total of 81 cases of oral cancers were matched with 162 controls in this hospital-based study. Information on sociodemographic characteristics and details of risk habits (duration, frequency and type of tobacco consumption and betel quid chewing) were collected. Association between smoking and betel quid chewing with oral cancer were analysed using conditional logistic regression. Results: Slightly more than half of the cases (55.6%) were smokers where 88.9% of them smoked kretek. After adjusting for confounders, smokers have two fold increased risk, while the risk for kretek consumers and those smoking for more than 10 years was increased to almost three-fold. Prevalence of betel quid chewing among cases and controls was low (7.4% and 1.9% respectively). Chewing of at least one quid per day, and quid combination of betel leaf, areca nut, lime and tobacco conferred a 5-6 fold increased risk. Conclusions: Smoking is positively associated with oral cancer risk. A similar direct association was also seen among betel quid chewers.

Factors Associated with Tobacco Use in Students Attending Local Government Schools in Mumbai, India

  • Chatterjee, Nilesh;Todankar, Priyamvada;Mandal, Gauri;Gupte, Himanshu;Thawal, Vaibhav;Bhutia, Tshering;Choudhuri, Leni
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권12호
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    • pp.5075-5080
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    • 2016
  • Purpose: Factors associated with ever-use and differences between ever-users and non-users of tobacco among adolescent school students from low income families in Mumbai were assessed. Materials and Methods: A self-administered questionnaire, completed by 1918 students from grades 7, 8 and 9 in 12 schools managed by the city municipal corporation in July 2015, gathered data on socio-demographic characteristics, tobacco use and tobacco-related knowledge, attitudes and beliefs. Results: Although only 1% of respondents thought tobacco was cool, nearly 35% were unaware of associations between tobacco use and health problems. Male students were almost twice as likely (OR=2.5, P <= 0.05) to have ever used tobacco compared to females and Supari (areca nut) users were eight times more likely (OR=8.99, P < 0.001) than Supari non -users. Tobacco-users were more likely to agree with statements: 'People who use tobacco have more friends' (OR=2.8, P = 0.004), 'Smoking relieves stress' (OR=5.6, P = 0.002) and 'It is possible to purchase any tobacco product within 100 yards of school' (OR=10.8, P < 0.001). Conclusion: This study highlights the gains made by tobacco prevention campaigns in that almost all students did not consider tobacco as cool or a stress reliever. However, they still need education about health consequences of tobacco-use. In addition, Supari use has to be addressed in school-based tobacco prevention and cessation initiatives. Furthermore, programs must also address perceptions and norms related to peers and tobacco use and ensure active implementation of existing laws. Such integrated measures will help ensure tobacco-free spaces around schools.

조선시대 자수 규방공예품의 유형과 특성 (Types and Characteristics of Women's Embroidered Handicrafts of the Joseon Dynasty)

  • 권수연;장연주
    • 복식
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    • 제59권4호
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    • pp.1-13
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    • 2009
  • The purpose of this study is to examine the types of and figurative characteristics of in women's embroidered handicrafts of Korea. It also aims to revive Korean traditional beauty, to examine the applicability of Korean traditional design that has both modern beauty and practicality, and to develop Korean women's embroidered handicrafts. The types of women's embroidered of Korea include Jumoni (pouches), Bojagi (wrapping cloths), and other accessories made by sewing. Jumoni consisting of 55.51% of them was the most frequently used handicraft followed by Bojagi (8.66%), and other accessories (35.83%). In terms of the patterns used, animal pattern and plant pattern were used the most frequently. In addition, complex patterns using two or three patterns together(70.49) were more frequent than singular patterns (29.53%). Pictorial type of pattern arrangement (58.24%) was used the most frequently and dense type (39.76%) and sparse type (2.00%) were followed. In terms of the materials on which embroidery was used, Dahn (85.82%) was used the most frequently followed by wool (5.67%), cotton (4.26%), silk (3.55%), and Sa (0.70%). Various techniques of stitches were used such as outline stitch (40.56%), satin and running stitch (29.32%), French nut stitch (28.11%), long and short stitch (21.28%), double leaf stitch (20.88%), and so on. Among them, satin stitch (63.05%) was the most popular type of stitch techniques. Strings (23.56%), maedeup (Korean traditional knots, 8.62%), or tassels (9.77%) were also attached for the purpose of both practicality and of decoration. There were some cases that added cloissone or red-pepper shaped decorations.

공신부인(恭愼夫人) 한씨(韓氏)에게 전달된 물품 및 출토복식 분석을 통한 15세기 조선 사대부 가 여성복식 고찰과 착장고증 (The Consideration and Historical Research of Joseon Ladies' Attire in the 15th Century by Analyzing Excavated Costumes and Presents for Lady Han, Gongsin-buin)

  • 최정
    • 복식
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    • 제66권7호
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    • pp.171-191
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    • 2016
  • Lady Han, Gongshin-buin(恭愼夫人韓氏: 1410~1483) was Gongnyeo of Ming emperor and sister of Han Hwak(韓確:1400~1456). The aim of this study is to analyze the characteristic of costume presents for Lady Han, and to investigate a part of Joseon women's attire in the 15th century. Most of the presents for Lady Han were native products of Joseon to help alleviate her homsickness, but surviving relics are very rare. The costume-related presents included daily accessories and fabrics such as natural ornaments, embroidered pouch, needle case, wig, wooden comb, portable knife with multi-blades, various colored plain silk [綿紬] and ramie. Also, preceding research analysis of costume relic were combined with study of presents for Lady Han's. The most salient costume of Joseon women in the 15th century was the symmetric collared jacket. In addition, ornamented jeogori, pouch with pine nut stitch, chima, jangot, jangsam, black veil[羅兀] made with ra or jeung, glass beads, paintings of Ming and Joseon can be references. Illustrations show 6 representative type of Joseon women's full attires in the 15th century are as follows. First, is a combination of 'symmetric collared jacket with peacock rank badge, jeoksam, chima, underwear' and 'hoa-a, janga-a, embroidered pouch, needle case, knife with multi-blades: presents for Lady Han'. Second, formal wear focusing on symmetric collared Jacket of cloud pattern. Third, formal wear focusing on multicolor ornamented jeogori. Fourth, town wear with jangot and neoul. Fifth, formal wear with jangsam. Sixth, daily wear focusing on banbi with symmetric squre collar. Accessories and underwear shown in another illustration were same as the first illustration. Results of this study can be used as content for making historically accutate costumes as well as costume education.

Suppression of β-catenin and Cyclooxygenase-2 Expression and Cell Proliferation in Azoxymethane-Induced Colonic Cancer in Rats by Rice Bran Phytic Acid (PA)

  • Saad, Norazalina;Esa, Norhaizan Mohd;Ithnin, Hairuszah
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권5호
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    • pp.3093-3099
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    • 2013
  • Background: Phytic acid (PA) is a polyphosphorylated carbohydrate that can be found in high amounts in most cereals, legumes, nut oil, seeds and soy beans. It has been suggested to play a significant role in inhibition of colorectal cancer. This study was conducted to investigate expression changes of ${\beta}$-catenin and cyclooxygenase-2 (COX-2) and cell proliferation in the adenoma-carcinoma sequence after treatment with rice bran PA by immunocytochemistry. Materials and Methods: Seventy-two male Sprague-Dawley rats were divided into 6 equal groups with 12 rats in each group. For cancer induction two intraperitoneal injections of azoxymethane (AOM) were given at 15 mg/kg bodyweight over a 2-weeks period. During the post initiation phase, two different concentrations of PA, 0.2% (w/v) and 0.5% (w/v) were administered in the diet. Results: Results of ${\beta}$-catenin, COX-2 expressions and cell proliferation of Ki-67 showed a significant contribution in colonic cancer progression. For ${\beta}$-catenin and COX-2 expression, there was a significant difference between groups at p<0.05. With Ki-67, there was a statistically significant lowering the proliferating index as compared to AOM alone (p<0.05). A significant positive correlation (p=0.01) was noted between COX-2 expression and proliferation. Total ${\beta}$-catenin also demonstrated a significant positive linear relationship with total COX-2 (p=0.044). Conclusions: This study indicated potential value of PA extracted from rice bran in reducing colonic cancer risk in rats.

동의보감 탕액편에 기재된 식이본초의 독성유무에 대한 분류 연구 (Study of Toxicity Presence Classification about Herbal Diet in Tang-aec-pyeon of Dong-ui-bo-gam)

  • 신호동;정종운
    • 대한한의학회지
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    • 제32권1호
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    • pp.12-35
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    • 2011
  • Objectives: The two criteria to clarify the toxicity of a herbal diet are well known. Although mechanical analysis of effective ingredients, a western approach, is widely used, the toxicity presence classification through the herbal analysis from a viewpoint of a theory of the herbal medicine properties has been disregarded. This study is for the safe use of a herbal diet through classification and study of toxicity presence in the herbal diet from the view of a theory of herbal medicine properties, one of the methods of Oriental Medicine. Methods: We classified and studied the toxicity presence in four kinds of herbal diets, waters and grains, animals groups, fruits and vegetables, and herbs and trees, excluding mineral natural drugs, of 1,400 kinds of medicines in 16 chapters of Tang-aec-pyeon, Dong-ui-bo-gam, for which the herbal analysis from a viewpoint of the theory of the herbal medicine properties has been used. The criteria of the toxicity presence in the herbal diet have been largely classified into the toxicant and the non-toxicant, and the toxicant is in turn classified into the insignificant, the medium and the significant. The category to clarify herbal diet has been limited to simultaneous utilization of food and natural drugs. The main text is Dong-ui-bo-gam, although diverse other references have also been used. Results: There are toxicant diets: a kind of tortoise meat of animals groups; five kinds of grains part in fruits and vegetables: aengdo, peach, oyat, small apple and gingko nut; and 12 kinds of vegetables part in fruits and vegetables: ginger, oriental cabbage, lettuce, chongbaek, onion, garlic, leek, fern, houttuynia cordata (myeol), pyeongji, geundae, and spinach, which should be prohibited from long-term use both as food and medicine. Conclusion: If herbal diet is used as health food supplements or food, the toxicity presence should be considered on the grounds of an Oriental Medicine theory of the herbal medicine properties.

주석 도금한 커넥터의 접촉 하중의 변화에 의한 전기 접촉저항 변화에 관한 연구 (A Study on the Variation of Electric Contact Resistance Due to Change in Contact Force in a Tin-plated Connector)

  • 유환신;오만진;박형배
    • 한국항행학회논문지
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    • 제18권4호
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    • pp.381-386
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    • 2014
  • 전기 커넥터에 영향을 주는 프레팅 부식 요인 중 하나인 접촉 부하의 영향을 조사하기 위하여, 프레팅 부식 표본 쌍을 두께 $3{\mu}m$의 두께를 갖는 주석으로 도금된 황동 표본을 사용하여 제조하였다. 접점의 전기저항은 프레팅 부식 시험 기간 동안 측정되었다. 프레팅 주기에서 저항은 증가하였다. 저항의 변화는 3단계로 나눌 수 있다. 첫 번째 단계는 미미하고 안정적인 저항을 나타내었다. 두 번째 단계는 저항이 꾸준한 증가를 보여 주었다. 그리고 세 번째 단계는 매우 높고 간헐적인 저항을 보여주었다. 실패주기(Nf)와 접촉력(P) 사이의 관계는 다음과 같이 표현될 수 있다. 각각의 하중, 변위, 온도 등 다양한 조건에서 프레팅 테스트를 통해 다양한 환경 조건 하에서 매우 높고 간헐적인 저항에 대응 전기 커넥터의 실패주기 예측공식의 표현이 가능할 것이다.