• Title/Summary/Keyword: Gradients

Search Result 1,176, Processing Time 0.032 seconds

Changes in Plasma Protein Concentration and Alveolar -Arterial Oxygen Tension Differnce Associated with CPB- (체외순환에 따른 혈장 단백 함량과 폐포모세혈관 산소 분압차의 변화)

  • 전태국
    • Journal of Chest Surgery
    • /
    • v.23 no.6
    • /
    • pp.1084-1089
    • /
    • 1990
  • Plasma protein concentration, plasma albumin concentration, hematocrit, and arterial blood gas tension were measured in 15 mongrel dogs undergoing heart transplantation with cardiopulmonary bypass. The hemodilution due to priming solution resulted in a 49% decrease in plasma protein concentration, a 57% decrease in plasma albumin concentration, a 46%a decrease in hematocrit. The measurements had returned to preperfusion values 1 hour after the end of cardiopulmonary bypass. The intraoperative changes in plasma protein and albumin concentration did not correlate with changes in alveolar-arterial oxygen tension gradients[D[A\ulcorner PO2]]. It is concluded that, in the absence of an increase in left atrial pressure, marked decrease in plasma protein concentration can be tolerated without the occurrence of pulmonary edema. And further study should be done to determine how to prepare an ideal priming solution.

  • PDF

A Study on the Relationship between Traffic Accident Rates and Geometric Characteristics of the Expressway in Korea (우리나라 고속도로의 기하특성과 교통사고발생률과의 상호관계에 관한 연구)

  • 임강원;강정규
    • Journal of Korean Society of Transportation
    • /
    • v.3 no.1
    • /
    • pp.3-21
    • /
    • 1985
  • Since the expressway was first opened in 1968 there has been continued demand for constructing new lines of expressway, and thus it amounts to 1,420.5km in total length as of 1984. As the expressway becomes to take up more important role in our country facing motorization traffic accidents have become more of social issues, although its accident rates are relatively low compared to those on general highways in Korea, which is among the highest in the world. The purpose of the study is to investigate the correlation between the traffic accident rates on the expressway and their geometric characteristics based upon 1982 data. In order to extract the correlationship among them on as much disaggregate basis, the study has carried out the analysis on the primary data aggregated on the 100 meter intervals. One of the important findings was, among others, the design criteria of the expressway should be reconsidered with respect to the radius of the curve, superelevation, climbing lane, composed gradients, interchange facilities, tunnels and so on.

  • PDF

Analysis on Inhomogeneous Textures Developed in Aluminum AA 1050 Sheets during Continuous Confined Strip Shearing (알루미늄 AA 1050 판재구속전단가공 시 불균질 집합조직 형성의 해석)

  • 이재필;석한길;허무영
    • Transactions of Materials Processing
    • /
    • v.13 no.4
    • /
    • pp.382-387
    • /
    • 2004
  • The continuous confined strip shearing (CCSS) based on the equal channel angular pressing (ECAP) was modeled by means of a rigid-plastic two-dimensional finite element method (FEM). Parallel to the simulations, samples of AA 1050 sheets were experimentally deformed by CCSS. The CCSS deformation led to the formation of through thickness texture gradients comprising a strong shear texture in the sheet center and weak shear textures in the sheet surfaces. FEM analysis revealed variations in the strain component $\varepsilon_13$ along the sample thickness direction, which gave rise to the evolution of different textures. A high friction between the sample and die surface was responsible for lowering intensities of the shear texture components in thickness layers close to the surfaces.

Hybrid Facial Representations for Emotion Recognition

  • Yun, Woo-Han;Kim, DoHyung;Park, Chankyu;Kim, Jaehong
    • ETRI Journal
    • /
    • v.35 no.6
    • /
    • pp.1021-1028
    • /
    • 2013
  • Automatic facial expression recognition is a widely studied problem in computer vision and human-robot interaction. There has been a range of studies for representing facial descriptors for facial expression recognition. Some prominent descriptors were presented in the first facial expression recognition and analysis challenge (FERA2011). In that competition, the Local Gabor Binary Pattern Histogram Sequence descriptor showed the most powerful description capability. In this paper, we introduce hybrid facial representations for facial expression recognition, which have more powerful description capability with lower dimensionality. Our descriptors consist of a block-based descriptor and a pixel-based descriptor. The block-based descriptor represents the micro-orientation and micro-geometric structure information. The pixel-based descriptor represents texture information. We validate our descriptors on two public databases, and the results show that our descriptors perform well with a relatively low dimensionality.

An area-based stereo matching algorithm using multiple directional masks (다중 방향성 마스크를 이용한 영역 기반 스테레오 정합 알고리즘)

  • 김낙현
    • Journal of the Korean Institute of Telematics and Electronics B
    • /
    • v.33B no.2
    • /
    • pp.77-87
    • /
    • 1996
  • Existing area-based stereo matching algorithms utilize a single rectangular correlation area for computing cross-correlation between corresponding points in stereo images, and compute disparity by finding the peak in the vicinity of depth discontinuity, since, because of inconstnat disparities around discontinuities, the cross-correlation becomes low in such area. Inthis paper, a new area-based matching strategy is proposed exploiting multiple directional correlation masks instead of a single one. The proposed technique computes multiple cross-covariance functions using each oriented mask. Peaks are detected from each covariance function and the disparity is computed by choosing the location with the highest covariance value. Proposed approach can also be applied to compute disparity gradients without obtaining dense depth data. A number of examples are presented using synthetic and natural stereo images.

  • PDF

NMR Measurement by Induction Method in a Low Magnetic Field (저자장에서 자기유도법에 의한 핵자기공명 측정)

  • 유권상;김창석
    • Journal of the Korean Magnetics Society
    • /
    • v.4 no.3
    • /
    • pp.277-281
    • /
    • 1994
  • The NMR signal by induction method was observed in a solenoid field of 1.0 mT. The center frequeocy and the half width at the half maximum of NMR signal were 42.588 Hz and 2.2 Hz in a field gradient of 3 ppm/cm. The NMR signals in different field gradients were compared with the theoretical values by considering the weighting factor of sample.

  • PDF

A Novel Method for a Reliable Classifier using Gradients

  • Han, Euihwan;Cha, Hyungtai
    • IEIE Transactions on Smart Processing and Computing
    • /
    • v.6 no.1
    • /
    • pp.18-20
    • /
    • 2017
  • In this paper, we propose a new classification method to complement a $na{\ddot{i}}ve$ Bayesian classifier. This classifier assumes data distribution to be Gaussian, finds the discriminant function, and derives the decision curve. However, this method does not investigate finding the decision curve in much detail, and there are some minor problems that arise in finding an accurate discriminant function. Our findings also show that this method could produce errors when finding the decision curve. The aim of this study has therefore been to investigate existing problems and suggest a more reliable classification method. To do this, we utilize the gradient to find the decision curve. We then compare/analyze our algorithm with the $na{\ddot{i}}ve$ Bayesian method. Performance evaluation indicates that the average accuracy of our classification method is about 10% higher than $na{\ddot{i}}ve$ Bayes.

Stress Analysis in Polymeric Coating Layer Deposited on Rigid Substrate

  • Lee, Sang Soon
    • Corrosion Science and Technology
    • /
    • v.14 no.4
    • /
    • pp.161-165
    • /
    • 2015
  • This paper presents an analysis of thermal stress induced along the interface between a polymeric coating layer and a steel substrate as a result of uniform temperature change. The epoxy layer is assumed to be a linear viscoelastic material and to be theromorheologically simple. The viscoelastic boundary element method is employed to investigate the behavior of interface stresses. The numerical results exhibit relaxation of interface stresses and large stress gradients, which are observed in the vicinity of the free surface. Since the exceedingly large stresses cannot be borne by the polymeric coating layer, local cracking or delamination can occur at the interface corner.

Nonlinear behavior of R/C cooling tower shells

  • Hara, Takashi;Kato, Shiro;Ohya, Makoto
    • Structural Engineering and Mechanics
    • /
    • v.5 no.5
    • /
    • pp.541-552
    • /
    • 1997
  • In this paper the ultimate strength of the R/C cooling towers, which have initial imperfection and pre-cracked elements, is analyzed. The initial geometric imperfections arise from the unavoidable inaccuracies under the construction and the pre-cracks are assumed to be produced by the temperature stress gradients or cyclic loading under wind pressure and/or earthquake load. Both effects are strongly influenced on the strength of the R/C cooling tower shell structures. The reinforcing ratio is also the important factor to evaluate the ultimate strength of the R/C cooling tower shells. However we could not analyze these structures experimentally because of their large, analyses are the powerful schemes to evaluate the safety and reliability of these structures. The analyzed model is Port Gibson cooling tower shell. In the numerical analysis the geometric and material nonlinearities are taken into account.

Evolution of temperature gradients during rolling of $Cu_{54}Ni_6Zr_{22}Ti_{18}$ bulk metallic glass in the super cooled liquid region (Cu기 비정질 합금의 과냉각 액상구간에서 온간 압연시 Roll 온도의 영향)

  • Park, E.S.;Lee, J.H.;Kim, H.J.;Bae, J.C.;Huh, M.Y.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • 2006.05a
    • /
    • pp.409-412
    • /
    • 2006
  • Bulk metallic glass (BMG) strips of $Cu_{54}Ni_6Zr_{22}Ti_{18}$ were produced by warm rolling of the amorphous powder canned with copper. Controlling of temperatures of the rolled sample and rolls was essential for the successive rolling process. Because improper controlling of the sample temperature gave rise to the crystallization of BMG loading to the catastrophic fracture of BMG strips, the temperature of rolls should be properly controlled for achieving successful powder rolling of BMG. The variations of the strain state and temperature in the roll gap was simulated by the finite element method(FEM) using various roll temperatures.

  • PDF