• Title/Summary/Keyword: nut

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Experimental study on stripping mechanism of tension controlled bolts (TC볼트의 스트리핑 메카니즘에 대한 실험적 연구)

  • 신근하
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.9 no.1
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    • pp.111-118
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    • 2000
  • Over tightening experiments of the tension-controlled bolts are carried out and the stripping mechanism is reviewed base on the observed results. There are two modes of bolt failure due to the over tightening : one the fracture of the bolt the other the thread stripping Bifurcation between these two modes is rather delicate but it seems being related with the elastic flexibility of the bolt which depends upon the unused thread length. The fracture mode occurs in the bolts with good flexibility while the latter with bad one. According to the ISO Standard some meter coarse threads like M20 and M22 have the same pitch which causes bigger fastener to less resistance in shear and bending compared with the smaller one. however since UNC thread system adapts different pitch for different nominal diameter unified coarse threads show better stripping resistance than their corresponding meter threads.

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Comparative Study of Fatty Acid Composition and Characterization of Fixed Oil of Four Peanut Varieties Available in Pakistan

  • Akhtar, Hifza;Hamid, Shahnaz;Khan, Javed Iqbal
    • Natural Product Sciences
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    • v.11 no.4
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    • pp.225-228
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    • 2005
  • four varieties of ground nut (Arechis hypogea) were collected from different areas of Pakistan (Tillagang, Gujar khan, Hanoi and Pipplan) from Punjab province. The oils were extracted for the evaluation of lipid. Physico-chemical values of oils were determined like refractive index, peroxide value, unsaponifiable matter, acid value, iodine value, free fatty acid and ester value. The lipid profile as indicated by GLC showed that Palmitic acid ranged from 8.2-8.8%, proportions of oleic acid and linoleic acid varied from 57.8-59.87% and 22.5-24.1% respectively. Gujar khan variety of peanut has higher % age of oil (56.79). The higher yield of oil in this variety is not at the cost of any nutritional quality of peanut oil.

The Development of Aluminum Pipe Support for Apartment Slabs(I) (공동주택 슬래브의 알루미늄 파이프서포트 개발에 관한 연구(I))

  • Cha, Jung-Koo;Yi, Young-Seop
    • Journal of the Korean Society of Safety
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    • v.27 no.5
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    • pp.105-110
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    • 2012
  • Steel elements are widely used for temporary structures on every construction site. but despite its strong resistences against heavy concrete volumes, they are easily eroded by oxygens in the space as times have been gone. If they are used several times in the construction fields, their elements are rusted and deformed and the strength is gradually reduced through the weak part. From this point of view, aluminum pipe support has been developed in stead of steel pipe sopport with enhancing durability against oxygens all the more. The developed aluminium pipe support has been lighter than steel unit, so workability has been improved. In another advantage of aluminium pipe support, different level control is possible with being equipped with the level control nut which enables the length adjustment of aluminium pipe support and the collapse of aluminum pipe support could be also prevented from the structures in the long term.

Vibration reduction of a pipe conveying fluid using the semi-active electromagnetic damper

  • Kavianipour, Omid
    • Coupled systems mechanics
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    • v.6 no.2
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    • pp.175-187
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    • 2017
  • This paper deals with a uniform cantilever Euler-Bernoulli beam subjected to follower and transversal force at its free end as a model for a pipe conveying fluid under electromagnetic damper force. The electromagnetic damper is composed of a permanent-magnet DC motor, a ball screw and a nut. The main objective of the current work is to reduce the pipe vibration resulting from the fluid velocity and allow it to transform into electric energy. To pursue this goal, the stability and vibration of the beam model was studied using Ritz and Newmark methods. It was observed that increasing the fluid velocity results in a decrease in the motion of the free end of the pipe. The results of simulation showed that the designed semiactive electromagnetic damper controlled by on-off damping control strategy decreased the vibration amplitude of the pipe about 5.9% and regenerated energy nearly 1.9 (mJ/s). It was also revealed that the designed semi-active electromagnetic damper has better performance and more energy regeneration than the passive electromagnetic damper.

Identification of protease-resistant proteins from allergenic nuts using two-dimensional gel electrophoresis and mass spectrometry

  • Santos, Ilyn L.;Lee, Ju-Young;Youm, Yujin;Lim, Jinkyu
    • Current Research on Agriculture and Life Sciences
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    • v.31 no.2
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    • pp.108-112
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    • 2013
  • Nuts are one of the most common sources of allergies in individuals of all ages. In order for a particular protein to render an allergic reaction, it must resist proteolytic digestion by intestinal enzymes. In this study, three well-known allergenic nuts, almonds, cashew nuts, and peanuts, were used as samples, and enzyme digestion with Bacillus protease and porcine pepsin was tested. A proteomic approach using two-dimensional gel electrophoresis and an MS/MS analysis was applied to visualize and identify the proteins that were resistant to enzyme digestion. Among the 150 protein spots tested, 42 proteins were assigned functions. Due to the lack of genomic databases, 41% of the identified proteins were grouped as hypothetical. However, 12% of them were well-known allergens, including AraH. The remainder were grouped as storage, enzymes, and binding proteins.

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CE Certification for Machinery Safety in Automated LCD Monitor Process (LCD 모니터 공정자동화 장비의 안전성에 대한 CE 인증)

  • Lee, Hwan-Deok;Jung, Won
    • Journal of Applied Reliability
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    • v.11 no.4
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    • pp.419-432
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    • 2011
  • In order to distribute machinery to European Union, it is mandatory to get CE marking to ensure the machinery is safe and reliable. The EHSR(Essential Health and Safety Requirements) of the EC Machinery Directive requires the machinery to be designed and manufactured to prevent from any dangerous situation. This study presents a case of CE Certification in Back Cover Nut Insert Machine and introduces an improvement method of product safety and reliability. This study also presents how to eliminate the deficiencies in design and manufacturing, and the process of applying EHSR for CE Marking.

A Experiment of the damping effect for Electromagnetic Damper using DC Motor and Ballscrew (DC Motor와 Ballscrew를 이용한 Electromagnetic Damper Damping 효과 실험)

  • Kang, Jeong-Ho;Lee, Hac-Choel;Jeong, Young-Suk
    • Proceedings of the KIPE Conference
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    • 2008.06a
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    • pp.124-126
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    • 2008
  • In this Paper, the modeling of the electromagnetic damper for automobile suspension is presented and the validation of the model is demonstrated by experiments. An electromagnetic damper, composed of a rotary DC motor, and a ball screw and nut. The damper then operates as a linear electric actuator. The damper then operate as a linear electric actuator. The results indicate the proposed system is feasible and it is proved that the electromagnetic damper has better than oil damper of passive control system.

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Fabrication and Characteristics of LB Ultra-thin Film Capacitor (I) (LB 초박막 커패시터의 제작 및 특성 (I))

  • 최용성;신훈규;권영수
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1995.11a
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    • pp.277-280
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    • 1995
  • We had experiment using LB method that can fabricate molecular order ultra-thin film below 100${\AA}$. LB mettled has known as main technology of information society in 21C, because it is nut only free oriention and alignment of molecular but also ability of thickness control as molecular order. In this paper, the fabricated condition and physical properities of functional ultra-thin film of molecular order was investigated and highly efficient ultra-thin film capacitor was fabricated by using ultra-thin LB film for application as electronic device. Possibility of ultra-thin film capacitor was researched by analizing rind measuring electrical properties. Polyimide ultra-thin LB film capacitor was fabricated, ensured theoretically rind experimentally its possibility in range of 10Hz∼ 1MHz through its frequency characteristics.

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Influence of Job Characteristics on the Use of Groupware and Job Performance (직무특성이 그룹웨어의 활용과 직무성과에 미치는 영향에 관한 연구)

  • 문태수;김승권
    • The Journal of Information Systems
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    • v.10 no.1
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    • pp.217-241
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    • 2001
  • Groupware technologies have become an important part of the business computing infrastructure in many organizations, but many groupware applications, especially those requiring significant collaboration among users, are still nut adequately used. The purpose of the paper is to explore the impact of groupware on the job performance. Recently, utilization of new information technology such as groupware can increase office productivity, but often this potential is not realized. Results of most studies indicate that groupware could increase the productivity of knowledge workers, who compose the majority of the labor force in the organization. The study on the impact of job characteristics on groupware and job performance is not sufficient. This study examines the influence of job characteristics such as job diversity, autonomy, and feedback on the use of groupware and job performance. In addition to that, this study examines the influence of the use of groupware on job performance. The results of regression analyses revealed that feedback was the major predictor of job performance, while autonomy and job diversity were the Haler predictors of the use of groupware. Also, the use of groupware were found to be important predictors of job performance.

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Characteristics of floating couplings of ball screw for high precision feeding system (고정밀 이송을 위한 볼스크류용 체결기구의 특성에 관한 연구)

  • 김인찬;박천홍;정윤교;이후상
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.04a
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    • pp.610-614
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    • 1996
  • As the run out error and misalignment of ball screw connected directly to guide table largely affect the motion accuracy of guideway, floating coupling that releases the table from screw nut except feed and rotational direction is needed todecrease its influences. The purpose of this study is to propose a practical model floating coupling of ball serew for high precision feeding system. The straightness, dynanic characteristics and micro step response of hydrostatic guideway, mounted with three types of coupling fixed type, leaf spring type and hydrostatic type, are tested and compared. From the resuts of experiments, it is proved that a hydrostatic type floating coupling is superior to other couplings and is available to high precision feeding system with ball screw.

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