• Title/Summary/Keyword: Simplex

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Effect of Condensation on Spray Characteristics of Simplex Swirl Nozzle (응축이 심플렉스 와류 노즐의 분무 특성에 미치는 영향)

  • Koh, Kwang-Uoong;Lee, Sang-Yong
    • Proceedings of the KSME Conference
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    • 2001.06e
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    • pp.107-112
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    • 2001
  • The effect of ambient gas (steam) condensation on swirl spray characteristics were studied experimentally for low subcooling condition of the liquid. The configuration of the liquid(water) sheet and the breakup modes were examined. Also variation of the discharge coefficient, breakup length, local and the cross-sectional area-averaged SMD of droplets with the liquid flow(injection) rate were obtained. The perforation breakup mode appears dominant with condensation while the aerodynamic wave breakup mode is dominant without condensation(in the air environment). The discharge coefficient, breakup length and the mean drop sizes decrease in a same manner with increasing of the liquid flow rate for both cases(with and without condensation). The condensation effects are insignificant with the discharge coefficient. However, the local and cross-sectional area-averaged SMD are larger and the breakup length becomes shorter in the steam environment. The spray angle predicted from the volumetric flux distribution along the radial direction of the sprays in the steam environment becomes larger with condensation.

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Triply-Encoded Hadamard Transform Imaging Spectrometer using the Grill Spectrometer (그릴 분광계를 사용하여 3중 부호화한 하다마드 변환 영상 분광계)

  • Kwak, Dae-Yun;Park, Jin-Bae;Park, Yeong-Jae
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.12
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    • pp.1527-1536
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    • 1999
  • In this paper, a triply-encoded Hadamard transform imaging spectrometer is proposed by applying the grill spectrometer to the Hadamard transform imaging spectrometer. The proposed system encodes the input radiation triply ; once through the input image mask and twice through the two masks in the grill spectrometer. We use an electro-optical mask in the grill spectrometer which is controlled by a left-cyclic simplex matrix. Then we modeled the system using $D^{-1}$ method. In this paper, the average mean square error associated with a recovered estimate is considered for performance evaluation. The relative performance is compared with those of the other conventional systems.

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AQuaKET Overview - A Nano-Accuracy Testing Method for Very Large Optics (AQuaKET 개괄 - 초대구경 나노정밀도 광학측정법)

  • 김영수
    • Proceedings of the Optical Society of Korea Conference
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    • 2002.07a
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    • pp.24-25
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    • 2002
  • 밀레니움을 전후하여 세계적으로 8m급 초대형 망원경들이 만들어지고 있다. ESO (European Southern Observatory)의 VLT (Very Large Telescopes) 4기, 미국 영국 카나다 등의 연합 Gemini telescope 2기, 일본의 Subaru 1기 등, 10여기의 망원경들이 완성되었고, 차세대 망원경들이 50m급으로 디자인되고 있다. 우주망원경도 지름 2.4m인 허블 우주망원경(Nubble Space Telescope)의 뒤를 이어 6m급의 차세대 우주망원경 (Next Generation Space Telescope)이 개발되고 있어서 2010년경에 발사될 예정이다. (중략)

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Propeller Skew Optimization Considering Varying Wake Field (선체반류를 고려한 프로펠러 최적 스큐화)

  • 문일성;김건도;유용완;류민철;이창섭
    • Journal of the Society of Naval Architects of Korea
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    • v.40 no.5
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    • pp.26-35
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    • 2003
  • Propellers operating in a given nonuniform ship wake generate unsteady loads leading to undesirable stern vibration problems. The skew is known to be the most proper and effective geometric parameter to control or reduce the fluctuating forces on the shaft. This paper assumes the skew profile as either a quadratic or a cubic function of the radius and determines the coefficients of the polynomial function by applying the simplex method. The method uses the converted unconstrained algorithm to solve the constrained minimization problem of 6-component shaft excitation forces. The propeller excitation was computed either by applying the two-dimensional gust theory for quick estimation or by the fully three-dimensional unsteady lifting surface theory in time domain for an accurate solution. A sample result demonstrates that the shaft forces can be further reduced through optimization from the original design.

Herpes Infection (임상가를 위한 특집 3 - 헤르페스 감염)

  • Lee, Sang-Shin;Lee, Suk-Keun
    • The Journal of the Korean dental association
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    • v.48 no.5
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    • pp.365-370
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    • 2010
  • Herpes virus family is highly infectious to patients, their families and dentists. The diagnosis of herpes infection is based on the characteristic clinical appearance and the location of the lesions. Herpes Simplex Virus(HSV) usually acquired through direct contact with infected lesions or body fluids, and the prevalence of HSV infection increases progressively from childhood. Primary infections provoke herpetic gingivostomatis typically affects the tongue, lips, gingival, buccal mucosa and palate. Recurrent infections give rise to vesiculo-ulcerative lesions at vermilion border of lip(herpes labialis). In the form of chickenpox, Varicella Zoster Virus(VZV) usually is infected in childhood. VZV spreads in the affected primary afferent nerve to the skin and produces a vesicular rash and pain. Epstein-Barr Virus(EBV) infects B cells and cause infectious mononucleosis. Latent EBV infection has also been implicated in Burkitt lymphoma, nasopharyngeal carcinoma. Cytomegalovirus(CMV) is associated with immune-compromised patient such as organ transplantation and AIDS patients.

Evolutionary Operation of Mixture Components Using Regular Simplex (정규 심플렉스를 이용한 혼합물 성분변수의 진화적 조업법)

  • Kim, Chi-Hwan;Byun, Jai-Hyun
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2004.05a
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    • pp.92-95
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    • 2004
  • A mixture experiment is a special type of response surface experiment in which the factors are the ingredients or components of a mixture, and the response is a function of the proportions of each ingredient. Evolutionary operation is useful to improve on-line full-scale manufacturing processes by systematically changing the levels of the process variables without jeopardizing the product. This paper presents an evolutionary operation procedure for large-scale mixture production processes based on simplex search procedure, which can be beneficial to practitioners who should improve on-line mixture process quality while meeting the production schedule of the mixture product.

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Higher Order Elements by Delaunay Triangulation (드로네이기법에 의한 고차 유한요소 생성)

  • 송영준
    • Computational Structural Engineering
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    • v.9 no.4
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    • pp.141-154
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    • 1996
  • Delaunay triangulation is a very powerful method of mesh generation for its versatility such as handling complex geometries, element density control, and local/global remeshing capability, The limit of generating simplex elements(3-node elements in 2-D) only is resolved by adding generation module of 6-node quadratic elements. Since proposed adjacency does not change from 3-node element mesh to 6-node mesh, generation module can utilize the original simplex element generator. Therefore, versatility of the Delaunay triangulation is preserved. A simple upsetting problem is employed to show the possibility of the algorithm.

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Detection of Magnetic Body using Magnetic Field Disturbances (자계교란을 이용한 자성체 탐지)

  • Lee, H.B.;Koh, C.S.;Hahn, S.Y.;Jung, H.K.;Choi, T.I.;Kim, K.C.
    • Proceedings of the KIEE Conference
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    • 1992.07b
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    • pp.577-579
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    • 1992
  • A new algorithm, which combines the Evolution Strategy and the Simplex method, is proposed for the detection of magnetic body utilizing the disturbance of magnetic fields. Although the detection problem of magnetic body which belongs to the inverse problem may have many local minima, the global optimum point was found by introducing the Evolution Strategy. And the convergency rate was enhanced by introducing the Simplex method. Through the numerical examples, the applicability and usefulness of the proposed algorithm are proved.

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A Case of Herpetic Whitlow with Bacterial Superinfection (세균이 중복감염된 Herpetic Whitlow 1례)

  • Chung, Ju-Young;Kim, Sang-Woo
    • Clinical and Experimental Pediatrics
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    • v.46 no.9
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    • pp.918-920
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    • 2003
  • Herpes simplex virus infection of the hand in children occurs after auto-inoculation from herpetic gingivostomatitis or herpes labialis. Herpetic whitlow should be suspected based on clinical signs. Diagnosis can be made by PCR or virus culture. Many misdiagnosed cases suggests that this disease is not sufficiently known. Surgical interventions may be harmful and should be avoided. We report a case of herpetic whitlow with bacterial superinfection in a three-year-old girl.

Revised Iterative Goal Programming Using Sparsity Technique on Microcomputer

  • Gen, Mitsuo;Ida, Kenichi;Lee, Sang M.
    • Journal of the Korean Operations Research and Management Science Society
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    • v.10 no.1
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    • pp.14-30
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    • 1985
  • Recently, multiple criteria decision making has been well established as a practical approach to seek a satisfactory solution to a decision making problem. Goal programming is one of the most powerful MCDM tools with satisfying operational assumptions that reflect the actual decision making process in real-world situations. In this paper we propose an efficient method implemented on a microcomputer for solving linear goal programming problems. It is an iterative revised goal simplex method using the sparsity technique. We design as interactive software package for microcomputers based on this method. From some computational experiences, we can state that the revised iterative goal simplex method using the sparsity technique is the most efficient one for microcomputer for solving goal programming problems.

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