• 제목/요약/키워드: initial MC

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Shrink-Wrapping 알고리즘을 이용한 단층영상으로부터의 표면 재구성 (Surface Reconstruction from Cross-Sectional Images using the Shrink-Wrapping Algorithm)

  • 박은진;최영규
    • 한국정보과학회논문지:시스템및이론
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    • 제34권1호
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    • pp.28-37
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    • 2007
  • 단층촬영 영상으로부터 임의의 등밀도 표면을 재구성하기 위한 새로운 방법을 제안하였다. 제안된 방법은 이 분야의 가장 대표적인 알고리즘인 마칭큐브에서와는 달리 단층영상에서 직접 등밀도 표면을 생성하지 않고 등밀도점을 먼저 추출하며, 셀경계 알고리즘을 이용하여 구한 초기메쉬의 각 정점들을 이들 등밀도점 방향으로 표면축소포장(Shrink-wrapping)하는 과정을 반복적으로 적용하여 등밀도 표면을 추출한다. 이렇게 함으로써 마칭큐브에서 나타나는 크랙이나 표면결정의 모호성이 발생하지 않고 안정적인 표면을 재구성 할 수 있다. 또한, 마칭큐브에서 O(1)-인접한 등밀도점만을 사용할 수 있는데 비해, 제안된 방법은 O(2) 및 O(3)-인접한 등밀도점을 표면재구성에 활용할 수 있게 함으로써 이론적으로 마칭큐브 알고리즘보다 더 정밀한 표면을 추출할 수 있도록 하였다. 실험을 통해 제안된 표면 재구성 알고리즘이 단층영상에서부터 등밀도면을 재구성하는데 매우 안정적이고 정확하며 효과적임을 확인할 수 있었다.

Kraft펄프의 효소표백반응에 미치는 페놀라디칼 전달체의 영향 (The Effects of Phenolic Radical Carriers on the Enzymatic. Bleaching of Kraft Pulp)

  • 류근갑
    • KSBB Journal
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    • 제10권2호
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    • pp.183-190
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    • 1995
  • 효소를 이용한 펄프의 전 처리가 펄프의 표백 효 과에 미치는 영향을 조사하였다. 펄프의 kappa number 감소율은, 효소를 사용하지 않고 IN NaOH 용액으로 추출하였을 경우에는 13.7% 였으나 xyla nase(EC 3.2.1.8, Pulpzyme HB)를 사용하여 전 처 리를 하였을 경우에는 IN NaOH 추출 후 25.2%로 증가하였다. Xylanase와 함께 peroxidase mc 1.11.1.7, Novozyme 502) 빛 $H_2O_2$(O.lmM)를 사용하여 전 처리를 하였을 때, 페놀성 물질을 radical carrier 로 사용할 수 있는 가능성을 조사하였다. Radical carner로서 guaiacol(ImM)을 사용하면 kappa number의 감소율이 29.6%로 증가하였다. 그러나 phenol, p-chlorophenol 등을 radical carrier로서 샤용하거나 높은 농도의 $H_2O_2$(ImM)를 사용할 경우 에는 kappa number의 감소율은 줄어들므로 radi cal의 생성 속도 및 radical의 안정성이 중요한 변수 가 됨을 알 수 있었다.

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A Study of Mobile and Internet Banking Service: Applying for IS Success Model

  • Koo, Chulmo;Wati, Yulia;Chung, Namho
    • Asia pacific journal of information systems
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    • 제23권1호
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    • pp.65-86
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    • 2013
  • Understanding success factors in electronic banking is important to helping banks succeed. In this study, we extend DeLone and McLean's IS success model to the electronic banking by adding trust as a success variable. We tested the extended model by comparing internet banking and mobile banking in Indonesia. Using a structural equation modelling approach. We found that system quality had positive impacts on perceived usefulness and end-user satisfaction for both internet banking and mobile banking. The development of e-banking (internet banking and mobile banking) in Indonesia is in its initial stage. Finally, although we tested for the common method bias to relieve concern, further research may use multiple methods when collecting the data. This study investigated the role of each dimension of IS success in the electronic banking environment. While the original IS success model emphasizes individual and organizational impacts, we have argued that trust is an important indicator of IS impact on an individual socially in the banking industry. The contribution of our study is two-fold. Conceptually, the study is the first to extend the IS success model to the e-banking context. We provide an extension of the updated IS success model by adding trust as an outcome variable in the research model.

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Liquid phase hydrogen peroxide decomposition for micro-propulsion applications

  • McDevitt, M. Ryan;Hitt, Darren L.
    • Advances in aircraft and spacecraft science
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    • 제4권1호
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    • pp.21-35
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    • 2017
  • Hydrogen peroxide is being considered as a monopropellant in micropropulsion systems for the next generation of miniaturized satellites ('nanosats') due to its high energy density, modest specific impulse and green characteristics. Efforts at the University of Vermont have focused on the development of a MEMS-based microthruster that uses a novel slug flow monopropellant injection scheme to generate thrust and impulse-bits commensurate with the intended micropropulsion application. The present study is a computational effort to investigate the initial decomposition of the monopropellant as it enters the catalytic chamber, and to compare the impact of the monopropellant injection scheme on decomposition performance. Two-dimensional numerical studies of the monopropellant in microchannel geometries have been developed and used to characterize the performance of the monopropellant before vaporization occurs. The results of these studies show that monopropellant in the lamellar flow regime, which lacks a non-diffusive mixing mechanism, does not decompose at a rate that is suitable for the microthruster dimensions. In contrast, monopropellant in the slug flow regime decomposes 57% faster than lamellar flow for a given length, indicating that the monopropellant injection scheme has potential benefits for the performance of the microthruster.

덱사메타존이 골아유사세포의 성장과 분화에 미치는 영향 (The Effects of Dexamethasone on Growth and Differentiation of Osteoblast-like Cell)

  • 이재목
    • Journal of Periodontal and Implant Science
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    • 제29권2호
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    • pp.277-289
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    • 1999
  • The ultimate aim of periodontal treatment is periodontal regeneration, which necessiates the regeneration of bone tissues. To evaluate the effects of Dex growth and differentiation of MC3T3-E1 cells, cells were seeded in alpha-modified eagle medium containing 10% fetal bovine serum, 10mM beta-glycerophosphate , $50{\mu}g/ml$ of ascorbic acid, with or without $10^{-7}M$ Dex and examined cell proliferation activities, alkaline phosphatase activities, and bone nodule formation until 25days. The results were as follows : 1. In Dex group, cell proliferation activities were lower until 15 days compared to control group. Bone nodules formation were showed at 10 days. 2. In the time-response effect, ALP activities were increased until the 10 days in control groups thereafter decreased and ALP activities of Dex group were lower aspect than control group until the 10 days In this study, bone nodule formation of osteoblast-like cells were accelerated by Dex and cell proliferation activities, ALP activity of Dex group showed lower than control group. Dex was considered that it did suppress initial growth, but accerelate mineralization of osteoblast-like cells.

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저속 2행정 디젤엔진의 과도 비틀림 진동에 의한 축계 피로 강도에 관한 연구 (A Study on Shaft Fatigue Strength due to Torsional Vibrations in Two Stroke Low Speed Diesel Engines)

  • 이돈출;김상환
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 추계학술대회논문집
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    • pp.786-791
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    • 2006
  • Two stroke low speed diesel engines are mainly used for marine propulsion or power plant prime mover. These have many merits such as higher thermal efficiency, mobility and durability. However various annoying vibrations sometimes occur in ships or at the plant itself. Of these vibrations, torsional vibration is very important and it should be carefully investigated during the initial design stage for engine's safe operation. In this paper authors suggest a new estimation method of for shaft's can be calculated equivalently from accumulated fatigue cycles number due to torsional vibration. The 6S70MC-C($25,320ps{\times}91rpm$) engine for ship propulsion was selected as a case study, and the accumulated fatigue cycles numbers for shafting life time converted from the measured angular velocity and torsional vibration stress was calculated. This new method can be realized and confirmed in test model ship with two stroke low speed diesel engine.

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Resuscitation from a pH of 6.5: A Case Report and Review of Pathophysiology and Management of Extreme Acidosis from Hypovolemic Shock after Trauma

  • Balmaceda, Alexander;Arora, Sona;Sondheimer, Ilan;Hollon, McKenzie M.
    • Journal of Trauma and Injury
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    • 제32권4호
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    • pp.238-242
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    • 2019
  • Extreme acidosis is a life-threatening physiological state that causes disturbances in the cardiovascular, pulmonary, immune, and hematological systems. Trauma patients commonly present to the operating room (OR) in hypovolemic shock, leading to tissue hypoperfusion and the development of acute metabolic acidosis with or without a respiratory component. It is often believed that trauma patients presenting to the OR in severe metabolic acidosis (pH <7.0) will have a nearly universal mortality rate despite aggressive resuscitation and damage control. The current literature does not include reports of successful resuscitations from a lower pH, which may lead providers to assume that a good outcome is not possible. However, here we describe a case of successful resuscitation from an initial pH of 6.5 with survival to discharge home 95 days after admission with almost full recovery. We describe the effects of acute acidosis on the respiratory and cardiovascular systems and hemostasis. Finally, we discuss the pillars of management in patients with extreme acute acidosis due to hemorrhage: transfusion, treatment of hyperkalemia, and consideration of buffering acidosis with bicarbonate and hyperventilation.

A BLMS Adaptive Receiver for Direct-Sequence Code Division Multiple Access Systems

  • Hamouda Walaa;McLane Peter J.
    • Journal of Communications and Networks
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    • 제7권3호
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    • pp.243-247
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    • 2005
  • We propose an efficient block least-mean-square (BLMS) adaptive algorithm, in conjunction with error control coding, for direct-sequence code division multiple access (DS-CDMA) systems. The proposed adaptive receiver incorporates decision feedback detection and channel encoding in order to improve the performance of the standard LMS algorithm in convolutionally coded systems. The BLMS algorithm involves two modes of operation: (i) The training mode where an uncoded training sequence is used for initial filter tap-weights adaptation, and (ii) the decision-directed where the filter weights are adapted, using the BLMS algorithm, after decoding/encoding operation. It is shown that the proposed adaptive receiver structure is able to compensate for the signal-to­noise ratio (SNR) loss incurred due to the switching from uncoded training mode to coded decision-directed mode. Our results show that by using the proposed adaptive receiver (with decision feed­back block adaptation) one can achieve a much better performance than both the coded LMS with no decision feedback employed. The convergence behavior of the proposed BLMS receiver is simulated and compared to the standard LMS with and without channel coding. We also examine the steady-state bit-error rate (BER) performance of the proposed adaptive BLMS and standard LMS, both with convolutional coding, where we show that the former is more superior than the latter especially at large SNRs ($SNR\;\geq\;9\;dB$).

Engineering run of CQUEAN

  • Park, Won-Kee;Kim, Eun-Bin;Jeong, Hyeon-Ju;Kim, Jin-Young;Lim, Ju-Hee;Choi, Chang-Su;Jeon, Yi-Seul;Pak, Soo-Jong;Im, Myung-Shin
    • 천문학회보
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    • 제35권2호
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    • pp.62.1-62.1
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    • 2010
  • CQUEAN (Camera for QUasars in EArly uNiverse) is an optical CCD camera system that consists of a science CCD camera, a guide CCD camera, and seven filters. In addition, a focal reducer is installed in front of the science camera to secure a larger field of view for the system. Engineering run of the system was carried out from Aug. 10, 2010 to Aug. 17, 2010, with 2.1m Otto Struve telescope at McDonald Observatory, USA, from which we investigated the characteristics and performance of the system. Bias and dark images were taken under various temperature conditions to examine the system behavior, and both twilight and dome flat images were obtained to investigate the appropriate preprocessing procedures of the data. Crude initial estimate indicated one hour integration would reach limiting magnitude of 24.2 in i-band with S/N ratio of 5, with CQUEAN at 2.1m telescope. The detailed results of the engineering run will be presented.

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패션 비주얼 메이커 닉 나이트(Nick Knight)의 작품특성 (Characteristics of Nick Knight's Works as a Fashion Visual Maker)

  • 김지영
    • 복식
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    • 제63권4호
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    • pp.101-117
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    • 2013
  • The purpose of this study is to consider the works of Nick Knight, the most influential fashion visual maker, to find out the characteristics of his works. For the research method, literature reviews were done by studying his book, viewing the articles on his official web site, reading journal review of his works and his interview articles. For the work analysis, fashion brands 'Christian Dior', 'Alexander McQueen', 'Martin Margiela', 'Hussein Chalayan' and 'Gareth Pugh' that have worked with Nick Knight were selected. The characteristics of his fashion works were derived from overall analysis of fashion visual works. The characteristics of Nick Knight's works are as follows. First is the 'innovation of image expression'. He used digital infra in advance and introduced digital images at the initial stage. He used fashion films as the means of communication and tried new image expressions in 3D. Second is 'breaking down the boundaries of creating process'. He worked with various field experts to make high quality works. He invited the public to participate in his creative process through the internet. Third is 'breaking down the categories of aesthetic expression'. He provided a wide variety of aesthetic standard and refused aesthetic stereotype. He broke the boundaries between fashion and art with a unique technique and high values.