• Title/Summary/Keyword: homogenous

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Time series prediction using virtual term generation scheme

  • Jo, Taeho;Cho, Sungzoon
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1996.04a
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    • pp.67-70
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    • 1996
  • The values measured at different time and enumerated sequentially by homogenous interval is called time series. Its goal is to predict values in future by analysing the measured values in past. The stastical approach to time series prediction tend to be by a neural approach with difficulties in expressing the reationship among past data. In neural approach, the preblem is the acquisting of the enough training data in advance. The goal of this paper is that such problem is solved by generating another term as virtual term between terms in time series.

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Basic Studies on Propellant Casting (Ⅰ). MO Theoretical Investigation of Structure and Reactivity of Curing Agent (추진제 성형에 관한 기초연구 (제1보). Curing Agent의 구조와 반응성에 관한 MO 이론적 고찰)

  • Ik Choon Lee;Ki Won Cha;Young Gu Cheun;Shi Choon Kim
    • Journal of the Korean Chemical Society
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    • v.25 no.3
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    • pp.140-144
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    • 1981
  • The structure and reactivity of isophorone diisocyanate, which is used as a curing agent in propellants casting, were investigated using the EHT, CNDO/2 and STO-3G MO methods. The results showed that the reactivity can be assessed by the positive charge on C atom of -NCO group. The structure of this compound was found to be such that it has slow polymerization rate but provides homogenous matrix for explosives.

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A Design and the Efficient Operation of Systolic Array for Polyadic-Nonserial Dynamic Programming Processing (Polyadic-Nonserial 동적 프로그래밍 처리를 위한 시스토릭 어레이의 설계 및 효율적인 운영)

  • 우종호;한광선
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.8
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    • pp.1178-1186
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    • 1989
  • In this paper, a systolic array for polyadic-nonserial DP problems is designed, the performance is analyzed and the efficient operating method is proposed. The algorithm is transformed to remove the broadcasting and global communication paths in the data dependence step by step. The transformed algorithm is mapping to the systolic array using the method proposed by D. I. Moldovan. The designed array is homogenous, had the processing elements of (n+1)/2 and 2n computation time ( n is the size of problem). In case of being many problems to process, the efficiency of array can be upward by inputing the problems successively. The interval between the initiations of two successive proboem instances is [n/2]+1 and the speed-up is about 4. The processor utilizations of each case are calculated.

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Loop-loop EM inversion and its applicability to subsurface exploration

  • Sasaki, Yutaka
    • 한국지구물리탐사학회:학술대회논문집
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    • 2006.06a
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    • pp.3-6
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    • 2006
  • There are three types of frequency-domain loop-loop EM induction method, depending on the loop separation and their location relative to the ground surface: horizontal-loop EM (HLEM), fixed small-loop EM, and helicopter-borne EM (HEM) methods. Multidimensional inversion provides tomographic images of the subsurface resistivity structure and thus enhances the interpretational accuracy of loop-loop EM data. HLEM method is shown to be effective for exploring groundwater resources in weathered and fractured crystalline basement terrains in semi-arid regions. Also, HEM method is useful for locating weak zones in landslide areas. The applicability of inversion to small-loop EM data depends solely on the S/N ratio. The quadrature response of small-loop EM data can only give the equivalent conductivity of a homogenous half-space model, and thus the in-phase component is essential in inverting EM data. However, the in-phase response is much lower and decreases more rapidly with decreasing frequency than the quadrature response. Further work is needed to obtain conductivity-depth images from small-loop EM data.

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Researches on the Enhancement of Plasticity of Bulk Metallic Glass Alloys

  • Kim, Byoung Jin;Kim, Won Tae
    • Applied Microscopy
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    • v.45 no.2
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    • pp.52-57
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    • 2015
  • Bulk metallic glass (BMG) shows higth strength, high elastic limit, corrosion resistance and good wear resistance and soft magnetic properties and has been considering as a candidate for new structural materials. But they show limited macroscopic plasticity and lack of tensile ductility due to highly localized shear deformation, which should be solved for real structural application. In this paper researches on the enhancement of plasticity of BMG were reviewed briefly. Introducing heterogeneous structure in glass is effective to induce more shear transformation zones (STZs) active for multiple shear band initiation and also to block the propagating shear band. Several methods such as BMG alloy design for high Poisson's ratio, addition of alloying element having positive heat of mixing, pre-straining BMG and variety of BMG composites have been developed for homogenous distribution of locally weak region, where local strain can be initiated. Therefore enhancement of plasticity of BMG is normally accompanied with some penalty of strength loss.

Diaphragmatic deformity in a cat mimicking a cardiac mass

  • Choi, Ran;Lee, Seung-Gon;Moon, Hyeong-Sun;Hyun, Changbaig
    • Korean Journal of Veterinary Research
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    • v.48 no.2
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    • pp.209-213
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    • 2008
  • A four-month-old intact femlae Abyssinian cat was present for routine health evaluation, because her littermate was recently died of ventricular septal defect. Diagnostic imaging studies showed a large caudal paracardiac mass in thoracic radiography and homogenous mass adjacent to heart in the echocardiography. Further echographic study revealed that the mass was liver and the diaphragmatic line was intact. The positive contrast celiogram revealed that no extravasation of the contrast media across the diaphragm and the prolapse of diaphragm into the pleural cavity. Based on our diagnostic imaging studies, the case was diagnosed as diaphragmatic deformity in a cat mimicking a cardiac mass.

5, 10, $20\;{\mu}m$ Silicon Diaphgrams and Features Fabricated without Using An Etch Stop (에치스탑을 사용하지 않고 제작된 5, 10, $20\;{\mu}m$ 두께의 실리콘 박막과 구조물)

  • Kwon, Yonung-Shin;Cho, Dong-Il
    • Proceedings of the KIEE Conference
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    • 1996.07c
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    • pp.1977-1979
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    • 1996
  • Single-crystaIline silicon diaphgrams and features are fabricated without using an etch stop process. The process involves vertical dry etching, double-sided alignment, followed by wet-chemical etching from the back side. The abvantages of this process are that $5{\sim}50{\mu}m$ diaphgrams and features can be fabricated accurately and inexpensively. In addition, since no impurity-based process is introduced, highly uniform and homogenous properties can be achieved

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Application of CFD to tile Calculation of 2 Phase Cryogenic Heat Transfer Processes (2상 극저온 열전달 과정 계산에서의 CFD 응용)

  • Liu, Jie.;Yue, Haibo;Chung, Mo;Bai, Cheol-Ho
    • 한국전산유체공학회:학술대회논문집
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    • 2011.05a
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    • pp.141-147
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    • 2011
  • A two-phase numerical model for plate-fin heat exchangers with plain fins and wave fins is studied incorporating the thermodynamic properties and the characteristics of fluid flow. The numerical simulations for the two fins in cryogenic conditions are earned out by employing a homogenous two-phase flow model with the CFD code ANSYS CFX. The heat transfer coefficients and the friction factor for nitrogen saturated vapor condensation process inside two types of plate fin heat exchanger are evaluated including the effects of saturation temperature (pressure), mass flow rate and inlet vapor quantity. The convective heat transfer coefficients and friction factors will be used for design of plate-fin type heat exchangers operating under cryogenic conditions.

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Solid medium integrated impedimetric biosensor for detection of microorganisms (미생물 검침을 위한 고체 배지 임피던스 센서)

  • Choi, Ah-Mi;Park, Jae-Sung;Jung, Hyo-Il
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.1629-1632
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    • 2008
  • Rapid, real-time detection of pathogenic microorganisms is an emerging and quickly evolving field of research, especially with regard to microorganisms that pose a major threat to public health. Herein, a new method that uses bioimpedance and solid culture medium for the real-time detection of microorganisms is introduced. We fabricated a new impedimetric biosensor by integrating solid media and two plane electrodes attached on two facing sides of an acryl well. During bioelectrical impedance analysis, the solid medium showed the characteristics of a homogenous conductive material. In a real-time impedance measurement, our solid-medium biosensor could monitor bacterial growth in situ with a detection time of ${\sim}4$ hrs. Our data indicate that the solid-medium biosensor is useful for detecting airborne microorganisms, thereby providing a new analytical tool for impedance microbiology.

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Bending analysis of softcore and hardcore functionally graded sandwich beams

  • Hadji, Lazreg;Safa, Abdelkader
    • Earthquakes and Structures
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    • v.18 no.4
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    • pp.481-492
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    • 2020
  • A New hyperbolic shear deformation theory is developed for the bending analysis of softcore and hardcore functionally graded sandwich beams. This theory satisfies the equilibrium conditions at the top and bottom faces of the sandwich beam and does not require the shear correction factor. The governing equations are derived from the principle of virtual work. Sandwich beams have functionally graded skins and two types of homogenous core (softcore and hardcore). The material properties of functionally graded skins are graded through the thickness according to the power-law distribution. The Navier solution is used to obtain the closed form solutions for simply supported FGM sandwich beams. The accuracy and effectiveness of proposed theory are verified by comparison with previous research. A detailed numerical study is carried out to examine the influence of the deflections, stresses, and sandwich beam type on the bending responses of functionally graded sandwich beams.