• Title/Summary/Keyword: initial MC

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

  • Park, Eun-Jin;Choi, Young-Kyu
    • Journal of KIISE:Computer Systems and Theory
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    • v.34 no.1
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    • pp.28-37
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    • 2007
  • This paper addresses a new surface reconstruction scheme for approximating the isosurface from a set of tomographic cross sectional images. Differently from the novel Marching cube algorithm, our method does not extract iso-density surface(isosurface) directly from the voxels but calculates the iso-density point(isopoint) first. After building the relatively coarse initial mesh by the Cell-boundary algorithm approximating the isosurface, it produces the final isosurface by iteratively shrinking and smoothing the initial mesh. Comparing with the Marching Cube algorithm, our method is robust and does not make any crack in resulting surface model. Furthermore, the proposed method surmounts the O(1)-adjacency limitation of MC in defining the isopoints by permitting the O(2) and O(3)-adjacent isopoints in surface reconstruction, and can produce more accurate isosurface. According to experiments, it is proved to be very robust and efficient for isosurface reconstruction from cross sectional images.

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

  • 류근갑
    • KSBB Journal
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    • v.10 no.2
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    • pp.183-190
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    • 1995
  • The effects of enzymatic pretreatments on the bleaching of kraft pulp were studied. The kappa number of pulp samples which represents the lignin content of pulp decreased by 25.2% by the pretreatments with xylanase(EC 3.2.1.8, Pulpzyme HB) while it decreased by 13.7% without enzyme pretreatments after the extraction of the pretreated pulp samples in 1N NaOH. To enhance the effects of enzymatic pretreatment on the bleaching of kraft pulp, phenols were used as radical carriers with the simultaneous use of peroxidase(EC 1.11.1.7, Novozyme 502), $H_2O_2$, and xylanase. Guaiacol (1mM) was most effective by decreasing the kappa number by 29.6% when a low initial concentration of $H_2O_2$ (0.1mM) was used. The use of either a higher initial concentration of $H_2O_2$ or phenols lacking electron donating substituents such as phenol and p-chloyophenol, however, decreased the efficiency of enzymatic pretreatment indicating that the production rate and the stability of phenolic radicals are important parameters.

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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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    • v.23 no.1
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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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    • v.4 no.1
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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.

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

  • Lee, Jae-Mok
    • Journal of Periodontal and Implant Science
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    • v.29 no.2
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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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A Study on Shaft Fatigue Strength due to Torsional Vibrations in Two Stroke Low Speed Diesel Engines (저속 2행정 디젤엔진의 과도 비틀림 진동에 의한 축계 피로 강도에 관한 연구)

  • Lee, D.C.;Kim, S.H.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.11a
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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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    • v.32 no.4
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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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    • v.7 no.3
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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
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.2
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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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Characteristics of Nick Knight's Works as a Fashion Visual Maker (패션 비주얼 메이커 닉 나이트(Nick Knight)의 작품특성)

  • Kim, Ji Young
    • Journal of the Korean Society of Costume
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    • v.63 no.4
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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.