• 제목/요약/키워드: Press-over

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굽힘 강도 향상을 위한 프레스 도어 임팩트 빔의 단면 설계 (The Section Design of Press Door Impact Beam for Improving Bending Strength)

  • 조경래;강성종
    • 한국자동차공학회논문집
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    • 제25권1호
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    • pp.74-81
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    • 2017
  • The door impact beam of the side-impacted vehicle plays a key role in securing occupant safety by preventing intrusion from the impacting vehicle. Despite the low production cost, the press door impact beam has been adopted sparingly because of the strength inferiority. In this study, the design technologies of the press beam aimed at improving bending strength were investigated. First, the effect of the section shape and size was examined. Next, thickness and material strength were increased. Also, the TRB beam application was simulated by varying combined thickness. Some TRB beams with reduced weight exhibited bending strength over the strength of the pipe beam. Then, the beam with a closed center section also showed remarkably enhanced maximum bending strength.

2014년 근로환경조사 데이터 분석 (2014 Korea Working Conditions Survey Data Analysis)

  • 김영선;이재희;백재욱
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제15권3호
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    • pp.181-191
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    • 2015
  • Change in labor time is affecting occupational safety and health. Recently reduction in labor time brought innovational operation method, investment in plant and equipment, and flexible labor time in some companies, thereby affecting working conditions for labourers. However, working conditions for some vulnerable social groups have deteriorated. As a result, they are becoming more exposed to risk factors such as injury and emotional stress. In this study we use 2014 KWCS data in order to find the social and demographic characteristics in Korean working conditions. To this end, we use exploratory data analysis approach to find the relationship between some of the important variables in the KWCS data. We also use Press-State-Response model to find which group of people are vulnerable to Press and State. We find that women, people over age 50 and business owners are more vulnerable to Press and State than men, people below age 50 and wage workers.

Improving the Gumbel analysis by using M-th highest extremes

  • Cook, Nicholas J.
    • Wind and Structures
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    • 제1권1호
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    • pp.25-42
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    • 1998
  • Improvements to the Gumbel method of extreme value analysis of wind data made over the last two decades are reviewed and illustrated using sample data for Jersey. A new procedure for extending the Gumbel method to include M-th highest annual extremes is shown to be less effective than the standard method, but leads to a method for calibrating peak-over-threshold methods against the standard Gumbel approach. Peak-over-threshold methods that include at least the 3rd highest annual extremes, specifically the modified Jensen and Franck method and the "Method of independent storms" are shown to give the best estimates of extremes from observations.

Highly Complex Green Parts in Excellent Quality

  • Nies, Norbert;Peters, Detlef
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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    • pp.747-749
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    • 2006
  • SMS Meer GmbH, formerly Mannesmann and today part of the SMS Group, has been building powder presses since the early 1950s. The patents developed here in this field have long since documented the pioneering work carried out for the PM industry. The paper focuses on the challenge of reconciling the contradictory demands in the production of highly complex and crack-free PM parts. The process employed with the patented Controlled Punch Adapter (CPA) [1] counters possible cracking reliably and directly at the source. In this way is it possible to develop new and highly complex parts to series production maturity in a minimum of time even without simulation of the press cycle [2]. The quality data achieved in the production series, almost 100% crack and micro crack-free green parts with optimum density distribution over all press levels is unrivalled and thus gives the user a clear lead over the competition.

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한국의 민주화와 미디어 : 정부와 시장 주류 미디어의 관계 (The relationship between the major market-based media and the government in Korea)

  • 조항제
    • 한국언론정보학보
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    • 제16권
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    • pp.168-206
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    • 2001
  • This study attempts to examine the relationships between the major market-based media and the government after closing military regime era, 1961-1987. After the military regime was collapsed, while the mass media in Korea obtained independence and autonomy from government, they have been confronted with the terrible competition not so much comparatively as before. The watchdog role in the traditional liberalism, which is regarded as normative relationship between the media and the government would be transformed in accordance with the market condition and the maturity of democracy. Thus, the watchdog metaphor has been variously deviated in rower-centered society; lap dog, guard dog, attack dog. liberalists argue that the primary democratic role of the media is to art as a public watchdog overseeing the state. Social democrats, however, criticize them as simplistic conception which could be only applied to the government. They argue that the media should be seen as a source of redress against the abuse of all forms of power over others; the home, the economy, and the civil society. The lap dog view is that the media is overwhelmingly dependent on the established power structure contrary to the watchdog. While the guard dog perspective is a means to preserve the power structure alarming with playing 'conflict role', the attack do8 aims to the private interest of the media in intruding into the politics. The attack dog perspective by T. Patterson could be composed of the interpretive style of report, the game schema report over the policy schema in the election, and the negativism against politics and government. The market-dominant press has been likely to transform from lap-guard dog into attack-guard dog. In Roh Tae Woo government(1988-1992), while the press was a lessened lap-guard dog before three parties merger in 1990, after merger the press had been transformed as the reinforced lap-guard dog because this merger entailed joint, party-to-party negotiations, and the formation of the new party preceded by dissolution of the ruling blot. In the early stage of Kim Young Sam government(1993-1997), the press has kept in pace with the reform movement drive-forced by the government. However, the press withdrew the support of Kim's reform in reaching the level of threat to ruling bloc. The press coalesced only circumstantially with government and was interested in preserving some margin of independence. The failure of Kim's reform proved the political muscle of the press in post-autho-ritarianism. In the middle stage of Kim Dae Jung government (1998-) that resulted in the shift of power structure as once-opposition party leader, the stress has been a manifested attack-guard dog owing to the anti-cold war policy, the realignment policy of power, and the minority-base of Kim's government. The press has endeavored to hold political communication within limits relatively less threatening to the established order.

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모바일 폰용 일체형 부품의 프로그레시브 성형공정 설계 (Progressive Process Design of Integrated Part for Mobile Phone)

  • 장명진;김강현;이찬주;김병민;이선봉;고대철
    • 소성∙가공
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    • 제20권2호
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    • pp.110-117
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    • 2011
  • The purpose of this work is to develop of a press forming process for mobile phone battery cover as an alternative to the current manufacturing process by laser welding. This press forming process consists of a combination of bending, side pressing and side bending operations. The dimensional error for each process was investigated by finite element(FE) analysis and the Taguchi optimization method. The spreading of the cover width in the side pressing process was adjusted by modifying the blank shape with a notch. The over-bending method was adopted to compensate the spring-back which occurs after bending. Forming experiments were performed to verify the reliability of the developed press forming process. In addition, the strength of the product was evaluated to verify the suitability of the battery cover manufactured with this new press forming process. The results of the forming experiments indicate that the dimensional accuracy of the battery cover is within the required tolerance. The strength of the battery cover was evaluated to 547N which is larger than required strength of 400N.

TPE를 적용한 자동차 윈도우 모터커버의 개발 (Development of Automobile Windows Motor Cover by Thermoplastic Elastomer(TPE))

  • 조영태;고범용;이충호
    • 한국생산제조학회지
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    • 제19권6호
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    • pp.847-851
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    • 2010
  • It was attempted to develop an auto part by over molding injection mold that produces precision products in high productivity with use of an eco-friendly TPE substitute material for NBR. NBR is currently used in motor gear cover, one of the key parts in motor module for auto doors. Gear cover is composed of plastics and rubber mostly today, which requires a two (2) step process for production using two presses of different types. A hot press is used at this time for forming the rubber, which has drawback of requiring a rather long forming time of 400 seconds for one forming process. Even though this difficulty is overcome by reducing production time through employment of multi-cavity molds, time for forming process must be shortened for improvement of the productivity eventually, and the existing method of insert injection for products that have been formed with plastic material must be outgrown. In this point of view, over molding injection using TPE has a big advantage. Forming time is shortened to 54 seconds, and working the two (2) processes in series by one (1) press could solve the durability problem caused by deflection of the plastics, not to mention shortening the process time. Enhancement of productivity by almost 80% and improvement in the accuracy of the product could thus be achieved.

고밀화에 의한 현사시 톱밥의 고형연료화 (High-pressure Compaction of Sawdust of Hyunsasi-poplar (Populus alba ${\times}$ P. glandulosa) for Densified Fuel)

  • 한규성;여진기
    • 임산에너지
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    • 제22권2호
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    • pp.54-59
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    • 2003
  • 최근 들어 북미와 유럽에서는 고밀화한 목질펠릿연료가 재생가능하며 카본뉴트럴한 바이오매스 에너지로서 널리 사용되고 있다. 본 연구에서는 현사시 톱밥의 고밀화를 통한 고형연료화에 관하여 연구하였다. 현사시 품종의 연료적 가치를 평가하기 위하여 열량 및 원소 분석을 수행하였다. 고밀화를 위하여 열압공정을 채택하였으며, 압밀화는 100∼180℃, 250∼1000 kgf/㎠, 2.5∼10분의 조건으로 행하였다. 고밀화연료의 특성은 밀도와 미세분 발생량으로 평가하였다. 목표치로서 고밀화연료의 전건밀도는 1.2 g/㎠ 이상, 5분간 진탕 후의 미세분 발생량은 0.5% 이하로 설정하였다. 목표 밀도와 목표미세분을 만족하기 위해서는 160℃ 이상의 압체온도가 요구되었다. 이 때의 압체압력은 750 kgf/㎠ 이상이 효과적이었다 180℃에서 1000 kgf/㎠으로 5분 이상의 압체가 고밀화연료 제조에 가장 적절한 조건으로 밝혀졌다.

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Representation of Disabled Community in Mainstream Media

  • Teng, Chan Eang;Joo, Tang Mui
    • International Journal of Knowledge Content Development & Technology
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    • 제10권2호
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    • pp.19-37
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    • 2020
  • There are limited research questioning the relationship between the disabled community and media, particularly in Malaysia. The lack of awareness and common assumption of specialty towards the disabled community have caused a small amount of local disability researches that question the relationship between the disabled community and the media. This research aims to find out the types of representation of disability in the Malaysian mainstream media, particularly press. Interview with visual disabled personnel and content analysis from news coverage of mainstream press are deployed in the study. The findings indicated the invalidity of disability culture as the misrepresentation of disabled community in Malaysia is not as severe as depicted by scholars because the news coverage focusing on them is getting more positive. Besides that, disabled people are not defensive towards the terms used to refer them as long as media practitioners do not over amplify their disability. The application of charity approach is still common in news coverage to portray the disabled community as victim, and therefore they are partially marginalized due to the misrepresentation in Malaysian mainstream press.

한국(韓國) 오프셋인쇄(印刷)의 인쇄적성(印刷適性) 향상(向上)에 관(關)한 연구(硏究) (A Study on the Improvement of Printability for The Offset Printing Press in Korea)

  • 이만교
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2006년도 춘계학술발표논문집
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    • pp.132-145
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    • 2006
  • In order to improve the printability for offset print in Korea, the experimental printing was performed with commercial press. The clue of this study is that the printing condition of the imported machines are not set properly for the Korean printing materials. Although almost all of the printing machines are imported, printing materials have to be supplied in Korea. So we need to study on the printability between Korean materials and imported machines. In spite of difficulties in experiments with commercial press, three newsprint machines and three commercial printing presses were used for this study over 5 years. As the results, the optimum range and printability coefficients were obtained.

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