• 제목/요약/키워드: Ideal Forming

검색결과 70건 처리시간 0.023초

Yield function of the orthotropic material considering the crystallographic texture

  • Erisov, Yaroslav A.;Grechnikov, Fedor V.;Surudin, Sergei V.
    • Structural Engineering and Mechanics
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    • 제58권4호
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    • pp.677-687
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    • 2016
  • On the basis of the energy approach it is reported a development of the yield function and the constitutive equations for the orthotropic material with consideration of the crystal lattice constants and parameters of the crystallographic texture for the general stress state. For practical use in sheet metal forming analysis it is considered different loading scenarios: plane stress and plane strain states. Using the proposed yield function, the influence of single ideal components on the shape of yield surface was analyzed. The six texture components investigated here were cube, Goss, copper, brass, S and rotated cube, as these components are typically observed in rolled sheets from FCC alloys.

BISTRO and BISTRO-2

  • 권우진
    • 천문학회보
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    • 제42권2호
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    • pp.79.1-79.1
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    • 2017
  • The B-fields In STar-forming Region Observations (BISTRO) is the 3-year large program of the James Clerk Maxwell Telescope (JCMT) using SCUBA-2 and POL-2, started in 2016. We aim to study the roles of magnetic fields in star formation by observing 16 fields of nearby star forming regions, e.g., Orion and Ophiuchus molecular clouds. The angular resolution and wavelength provided by JCMT (14 arcsecond at 850 micrometer) is ideal to investigate the intermediate scales of magnetic fields (1000-10000 au) associated in cold dense cores and filaments. This year, moreover, we were awarded JCMT time for additional 16 fields (BISTRO-2), which allows us to cover broader physical properties of star forming regions. We report the current status of BISTRO and introduce BISTRO-2.

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LED를 PLS 배열로 사용한 시역 형성 광학계가 없는 3차원 영상의 시역에 대한 연구 (Study on 3 Dimensional Images Using LED by PLS with No Viewing Zone Forming Optics)

  • 최규환;김성규;손정영
    • 한국광학회지
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    • 제19권2호
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    • pp.116-121
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    • 2008
  • 본 연구는 2차원 PLS(Point Light Source) 배열과 디스플레이 장치의 조합을 통하여 시역형성용 광학판이 없는 3차원 영상을 재생하는 방법에 관한 것이다. PLS를 사용하여 3차원 영상을 디스플레이 하는 경우 기존의 시차장벽(parallax barrier), 렌티큘러(lenticular), 마이크로 렌즈(microlens lens) 등의 광학판을 사용할 때 발생하는 여러 가지 광학적 문제점 등을 해소할 수 있다. PLS로 사용된 LED 광원이 가져야 할 특성을 조사하였으며 PLS 배열을 통한 입체영상 디스플레이의 시역에 대해 실험을 통하여 입증 하였다.

Analysis of Output Pulse of High Voltage and Nanosecond Blumlein Pulse Generator

  • Roh, Young-Su;Jin, Yun-Sik
    • Journal of Electrical Engineering and Technology
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    • 제8권1호
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    • pp.150-155
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    • 2013
  • A high voltage and nanosecond Blumlein pulse generator has been developed to produce an output pulse whose voltage level is greater than 250 kV and pulse duration 5 ns. The generator consists of various components such as a charging circuit, a pulse transformer, and a spark gap switch. As a heart of the generator, a Blumlein pulse forming line has been constructed in the cylindrical form using three cylindrical aluminum electrodes that are placed concentrically. Unlike the ideal Blumlein line, the output pulse of an actual Blumlein line may be affected by stray inductances and capacitances of switching and charging components, thereby degrading the performance of the generator. In this paper, PSPICE simulations have been performed to examine effects of stray inductances and capacitances on waveforms of output pulses. Simulation results show that the pulse waveform is significantly distorted mainly by the stray inductance of the spark gap switch.

Approaches to Reduce the Contact Resistance by the Formation of Covalent Contacts in Graphene Thin Film Transistors

  • Na, Youngeun;Han, Jaehyun;Yeo, Jong-Souk
    • Applied Science and Convergence Technology
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    • 제26권4호
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    • pp.55-61
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    • 2017
  • Graphene, with a carrier mobility achieving up to $140,000cm^2/Vs$ at room temperature, makes it an ideal material for application in semiconductor devices. However, when the metal comes in contact with the graphene sheet, an energy barrier forms at the metal-graphene interface, resulting in a drastic reduction of the carrier mobility of graphene. In this review, the various methods of forming metal-graphene covalent contacts to lower the contact resistance are discussed. Furthermore, the graphene sheet in the area of metal contact can be cut in certain patterns, also discussed in this review, which provides a more efficient approach to forming covalent contacts, ultimately reducing the contact resistance for the realization of high-performance graphene devices.

BISTRO: Magnetic Fields in Serpens Main

  • 권우진
    • 천문학회보
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    • 제44권1호
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    • pp.41.2-41.2
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    • 2019
  • The B-fields In STar-forming Region Observations (BISTRO 1 and 2) is a large program of the James Clerk Maxwell Telescope (JCMT) using SCUBA-2 and POL-2, starting in 2016. We aim to study the roles of magnetic fields in star formation by observing 32 fields of nearby low-mass and high-mass star forming regions. The angular resolution and the wavelength provided by JCMT (14 arcsecond at 850 micrometer) are ideal to investigate the intermediate scales of magnetic fields (1000-20000 au) associated in cold dense cores and filaments. We report the current status of this project and discuss the magnetic fields of the Serpens Main molecular cloud in which several filaments with various physical properties have been identified.

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유동성형에서의 연소관 예비성형체 두께별 소성변형 형태 (The Plastic Deformation of Combustion Chamber During the Flow Forming Process with Initial Preform Thickness)

  • 윤수진;이경훈;은일상
    • 한국추진공학회지
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    • 제1권1호
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    • pp.89-103
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    • 1997
  • 현재 각종 미사일의 추진기관용 연소관을 제작하는데 이용되고 있는 유동성형공정에 대하여 강소성 구성방정식을 이용 유한요소해석을 수행하였다. 종전의 단일 롤러에 의한 해석과는 달리 3개의 롤러에 의한 연소관의 점진 소성변형을 고려하였으며, 이에 따른 각 롤러의 연소관에 대한 소성변형, 응력분포가 관찰, 분석되었다. 해석 결과 예비성형체의 두께에 따라 소성변형 형태와 그에 따르는 응력분포에 많은 차이가 나는 것으로 밝혀졌다. 또 이상적인 유동성형조건 하에서 반경 방향으로의 연소관의 유효 소성변형도는 거의 균일하게 나타났다.

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자기이미지의 의류 광고에 대한 영향 -이론적 고찰- (The Influence of Self-image in Clothing Advertising -Theoretical Study-)

  • 김수경;임숙자
    • 한국의류학회지
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    • 제20권6호
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    • pp.1002-1015
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    • 1996
  • Self-image is an organized structure of perceptions of one's self and it has a direct influence on values, ideas, goals and objective. And It is generally agreed that consumers engage in buying behavior that is consistent and congruent with their self-image. With this assumptions numerous researches have prove that consumers tends to favor the brand or store image that is congruent to self-image. According to these results we can assume that self-image also can have influence on consumer's information processing, especially in advertising process. Because one of the main factor in forming the brand or store image is advertising. Thus, this study is to propose it's effect of self-image in clothing advertising process. In specifically to find out congruency between self-image and clothing ad image's influence on ad recalling, ad attitude and buying intention. And also it's difference between ideal self and actual self. This study suggested that when there is a congruency between self-image and clothing ad image, consumers have more positive attitude toward the clothing ad and have more intention to buy the products ann also can recall more frequently. Considering the characteristics of clothing goods as a symbolical goods, ideal self-image is more effective than actual self-image.

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비원형 단면에 대한 판재 성형성(I) (직사각형 단면에 대하여) (Formability of Sheet Metal in Noncircular Cup Drawing(I) (for Rectangular Cross Section))

  • 신재현;김민수;서대교
    • 한국자동차공학회논문집
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    • 제2권1호
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    • pp.84-95
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    • 1994
  • The effects of punch and blank shapes in the rectangular cup drawing process are examined experimentally to improve the formabilities. For this purpose, three blank shapes which are h-bl., G-bl., and T-bl., and five punch shape factors which are the ratios of two adjacent side lengths in rectangular cross section are adopted. The constructing methods of the three blank shapes are as follows. The h-bl. is designed by slip-line theory, and the G-bl. is selected for the similar shape to the punch. The T-bl. is obtained by the drawing method which is introduced in the technical references. The five punch shape factors are selected for length/width=1, 1.25, 1.5, 1.75 and 2. The experimental procedures are performed for all the above forming conditions to investigate and compare the formabilities. As a result, it is verified experimentally that the rectangular cups drawn by the h-bl. are more ideal than those drawn by G-bl. and T-bl.. They have not only higher limiting drawing ratio, more uniformity in drawn cup heights and more ideal thickness distributions, but also need relatively less maximum drawing forces.

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나르시시즘과 이상화 - 카레르의 소설과 오종의 영화에 나타나는 주인공 사례분석을 통하여 (Narcissism and Idealization through the Analysis of Carrère's novel and Ozon's Film)

  • 오정민
    • 비교문화연구
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    • 제19권
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    • pp.101-126
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    • 2010
  • Narcissism is a pathological phenomenon and narcissistic subject always needs to put itself on the top and has interest in nothing but its own determination. The protagonist of Adversary by ?mmanuel Carr?re does pay careful attention to what others are thinking of him while he does not distinguish difference between object of love and himself. So he can be allegedly narcissistic subject. And it can be said that the behaviors of Mary in the movie Under the sand by Ozon are included in narcissism in that narcissistic subject has the characteristics that idealizes the object of libido. However, in this study, the heroine is examined based on such a point that the object of love and extreme idealization incline toward others. We call this case reverse-narcissism. In Part 2, it is investigated what relation narcissism as an unconscious psychological tool has with Oedipus complex, which plays an important role in forming human psyche. For instance, disappointment caused by prohibition at the oedipal stage is too severe, which creates superego and its idealization to protect in such a way that narcissistic regression can not be done. Cases of extremely big gap between ego and ideal type are perversion, impostor, mania, paranoia, etc, where narcissistic and oedipal elements are combined to affect.