• 제목/요약/키워드: back-order

검색결과 2,314건 처리시간 0.031초

배압성형을 이용한 냉간단조 헬리컬 기어의 치수정밀도 향상에 관한 연구 (A Study on Improvement of Dimensional Accuracy of Cold forged Helical Gears using Back Pressure Forming)

  • 김홍석;정현철;이영선;강성훈;이일환;최석탁
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2009년도 춘계학술대회 논문집
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    • pp.139-142
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    • 2009
  • As important mechanical elements, gears have been used widely in power transferring systems such as automobile transmission and there have been several researches trying to make gear parts with cold or warm forging in order to reduce cost and time required to gear manufacturing process. Although forging processes of spur and bevel gears have been developed as practical level owing to active previous researches in Korea, the manufacturing of helical gear has been still depended on traditional gear cutting processes such as hobbing, deburring and shaving. In order to manufacture helical gears with cold forging process, a research project supported by government has been conducted by Daegu university, KIMS and TAK and this paper deals with effects of back pressure forming technique to cold forging of helical gear as a fundamental research.

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Psycho-acoustic evaluation of the indoor noise in cabins of a naval vessel using a back-propagation neural network algorithm

  • Han, Hyung-Suk
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제4권4호
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    • pp.374-385
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    • 2012
  • The indoor noise of a ship is usually determined using the A-weighted sound pressure level. However, in order to better understand this phenomenon, evaluation parameters that more accurately reflect the human sense of hearing are required. To find the level of the satisfaction index of the noise inside a naval vessel such as "Loudness" and "Annoyance", psycho-acoustic evaluation of various sound recordings from the naval vessel was performed in a laboratory. The objective of this paper is to develop a single index of "Loudness" and "Annoyance" for noise inside a naval vessel according to a psycho-acoustic evaluation by using psychological responses such as Noise Rating (NR), Noise Criterion (NC), Room Criterion (RC), Preferred Speech Interference Level (PSIL) and loudness level. Additionally, in order to determine a single index of satisfaction for noise such as "Loudness" and "Annoyance", with respect to a human's sense of hearing, a back-propagation neural network is applied.

요통의 물리치료적 접근 -원인과 물리적진단 중심으로- (The Phsical therapeutic Approache of Low Back Pain On the Study of Cause and Phscal Examination)

  • 박윤기;박지환
    • The Journal of Korean Physical Therapy
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    • 제3권1호
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    • pp.221-227
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    • 1991
  • Regardless of the age, Low back pains are appeared to the highest occurrence ratio and every one meet with the disease once at least through life. In order to treat a pain, therefore, it make a accurated treatment program by the accurated a cause and evaluation and can expected to effects of treatment. In order to do the perfected physical therapy, futhermore, it is nessessary more systematic studies not a cause and physical diagnosis but pathological aspects.

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QoS Based Routing Algorithm with Crank-Back Ability

  • Kanthavong, Somphone;Tangtisanon, Prakit;Lertwatechakul, Mayuree
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.2413-2417
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    • 2003
  • This paper proposes an improvement of a QoS based routing protocol. The hierarchical source routing algorithm[4] was improved by including of the Crank-Back algorithm[2]. The Crank-Back capability is the ability to solve the problem of selecting the wrong route because of using unsynchronized routing information in the ingress router. In order to reduce time of reversing the call-setup process back to the ingress router, spare-route information is included with a call-setup packet. Spare-route information could be used by every router to find the next appropriated link itself when insufficient resource of the selected link was found. The proposed algorithm improves the performance of the source routing call-setup process significantly.

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Numerical Analysis of Back Scattering from a Target over a Random Rough Surface Using DRTM

  • Yoon, Kwang-Yeol
    • Journal of electromagnetic engineering and science
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    • 제10권2호
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    • pp.61-66
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    • 2010
  • This paper is concerned with an analysis of the back scattering of electromagnetic waves from a target moving along random rough surfaces such as the desert, and sea. First, the discrete ray tracing method(DRTM) is introduced, and then, this method is applied to the back scattering problem in order to investigate the effect of the back scattering from random rough surfaces on the electric field intensities. Finally, numerical examples of various height deviations of the Gaussian type of rough surfaces are shown. It is numerically demonstrated that the back scattering is dominated by the diffractions related to the reflections from the random rough surfaces.

『의학입문(醫學入門)·요통(腰痛)』의 문헌 근거 - 『동의보감(東醫寶鑑)·요통(腰痛)』과 비교 - (Reference Research on Low Back Pain in Uihagimmun(醫學入門) - Compared with Donguibogam(東醫寶鑑) -)

  • 조학준
    • 대한한의학원전학회지
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    • 제27권2호
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    • pp.119-135
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    • 2014
  • Objectives : In order to research references on low back pain in Uihagimmun Methods : In respect of causes, symptoms and prescriptions for all kinds of low back pain, enlarging the range of references from books regarded as its references in Jiprye(集例) to books referred in Yeokdaeuihakseongssi(歷代醫學姓氏). Results : Beside of the books referred in Jiprye(集例) such as Seuideukhyobang(世醫得效方), Dangyesimbeop(丹溪心法), Okgimiui(玉機微義) and Injejikji(仁齋直指), the other reference books must be Sanghannon(傷寒論), Geumgweyoryak(金匱要略), Samingeugilbyeongbangjeungnon(三因 極一病證方論), Jebyeongwonhuron(諸病源候論), Jesaengbang(濟生方), Dongwonsihyobang(東 垣試效方), Maeginjeungchi(脈因證治), Bojebang(普濟方), Uihakjeongjeon(醫學正傳), Jeungchiyogyeol(證治要訣), Uihakgangmok(醫學綱目), Manbyeonghoechun(萬病回春), Gogeumuigam(古今醫鑑) and Susebowon(壽世保元) etc. Conclusions : Icheon(李梴), the author of Uihagimmun, referred not only to books mentioned in Jiprye but to books referred in Yeokdaeuihakseongssi. This book had important effect on making the contents of low back pain in Donguibogam(東醫寶鑑).

평면이방성 알루미늄 재료의 귀발생 예측에 있어서 항복함수와 초기 Back-Stress의 영향 (Influence of yield functions and initial back stress on the earing prediction of drawn cups for planar anisotropic aluminum alloys)

  • 윤정환;;정관수;양동열;장성기
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1998년도 춘계학술대회논문집
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    • pp.58-61
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    • 1998
  • Anisotropy is closely related to the formability of sheet metal and should be considered carefully for more realistic analysis of actual sheet metal forming operations. In order to better describe anisotropic plastic properties of aluminum alloy sheets, a planar anisotropic yield function which accounts for the anisotropy of uniaxial yield stresses and strain rate ratios simultaneously was proposed recently[1]. This yield function was used in the finite element simulations of cup drawing tests for an aluminum alloy 2008-T4. Isotropic hardening with a fixed initial back stress based on experimental tensile and compressive test results was assumed in the simulation. The computation results were in very good agreement with the experimental results. It was shown that the initial back stress as well as the yield surface shape have a large influence on the prediction of the cup height profile.

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Temperature-Adaptive Back-Bias Voltage Generator for an RCAT Pseudo SRAM

  • Son, Jong-Pil;Byun, Hyun-Geun;Jun, Young-Hyun;Kim, Ki-Nam;Kim, Soo-Won
    • ETRI Journal
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    • 제32권3호
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    • pp.406-413
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    • 2010
  • In order to guarantee the proper operation of a recessed channel array transistor (RCAT) pseudo SRAM, the back-bias voltage must be changed in response to changes in temperature. Due to cell drivability and leakage current, the obtainable back-bias range also changes with temperature. This paper presents a pseudo SRAM for mobile applications with an adaptive back-bias voltage generator with a negative temperature dependency (NTD) using an NTD VBB detector. The proposed scheme is implemented using the Samsung 100 nm RCAT pseudo SRAM process technology. Experimental results show that the proposed VBB generator has a negative temperature dependency of -0.85 $mV/^{\circ}C$, and its static current consumption is found to be only 0.83 ${\mu}A$@2.0 V.

커널 백피팅 알고리즘 기반의 가중 β-지수승 최소평균제곱오차 추정방식을 적용한 보컬음 분리 기법 (Vocal separation method using weighted β-order minimum mean square error estimation based on kernel back-fitting)

  • 조혜승;김형국
    • 한국음향학회지
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    • 제35권1호
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    • pp.49-54
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    • 2016
  • 본 논문에서는 커널 백피팅 알고리즘에 가중 ${\beta}$-지수승 최소평균제곱오차 추정방식(weighted ${\beta}$-order minimum mean square error: WbE)을 적용한 보컬음 분리 방식에 대해 제안한다. 음성 향상 방식에서, WbE는 진폭 성분 기반 MMSE(Minimum Mean Square Error) 추정방식, 로그 스펙트럼 진폭 기반 MMSE 추정방식 등과 같은 기존의 베이지안(Bayesian) 기반의 추정방식들 보다 객관적 및 주관적 측면에서 모두 보다 높은 성능을 나타내는 방식으로 잘 알려져 있다. 이에 본 논문에서는 기본적인 반복적 커널 백피팅 알고리즘에 WbE를 적용하여 음악 신호에서의 보컬음 분리 성능을 향상시키고자 하였다. 실험결과는 본 논문에서 제안한 방식이 기존의 분리 방식보다 분리 성능이 더 뛰어나다는 것을 보인다.