• 제목/요약/키워드: Volume Integration

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Computation of Water and Air Flow with Submerged Hydrofoil by Interface Capturing Method

  • Kwag, Seung-Hyun
    • Journal of Mechanical Science and Technology
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    • 제14권7호
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    • pp.789-795
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    • 2000
  • Free-surface flows with an arbitrary deformation, induced by a submerged hydrofoil, are simulated numerically, considering two-fluid flows of both water and air. The computation is performed by a finite volume method using unstructured meshes and an interface capturing scheme to determine the shape of the free surface. The method uses control volumes with an arbitrary number of faces and allows cell wise local mesh refinement. The integration in space is of second order, based on midpoint rule integration and linear interpolation. The method is fully implicit and uses quadratic interpolation in time through three time levels. The linear equations are solved by conjugate gradient type solvers, and the non-linearity of equations is accounted for through Picard iterations. The solution method is of pressure-correction type and solves sequentially the linearized momentum equations, the continuity equation, the conservation equation of one species, and the equations for two turbulence quantities. Finally, a comparison is quantitatively made at the same speed between the computation and experiment in which the grid sensitivity is numerically checked.

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An Analytical Approach to Color Composition in Ray Tracing of Volume Data

  • 정문렬;백두원;김웅환
    • 한국컴퓨터그래픽스학회논문지
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    • 제2권1호
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    • pp.1-6
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    • 1996
  • 3차원 체적데이터의 광선추적법에서는, 영상을 구성하는 각 화소의 색깔을 보통 각 화소점에서부터 발사한 광선 위의 각 표본점들이 미치는 영향의 합으로 구한다. 이 합을 자연스럽게 표현하는 법은 적분이다. 그러나, 대부분의 방법에서는 적분을 통한 분석적 해법을 찾기 어렵기 때문에 수치누적계산법을 통하여 구한다. 본 논문에서는 체적데이터의 광선추적법을 위한 분석적 해법을 구할 수 있다는 것을 보여준다. 끝으로 우리의 접근법에 대한 의의와 유용함에 대한 가설적인 결론을 실험에 근겋여 이끌어낸다.

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Reduced Gray Matter Volume of Auditory Cortical and Subcortical Areas in Congenitally Deaf Adolescents: A Voxel-Based Morphometric Study

  • Tae, Woo-Suk
    • Investigative Magnetic Resonance Imaging
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    • 제19권1호
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    • pp.1-9
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    • 2015
  • Purpose: Several morphometric studies have been performed to investigate brain abnormalities in congenitally deaf people. But no report exists concerning structural brain abnormalities in congenitally deaf adolescents. We evaluated the regional volume changes in gray matter (GM) using voxel-based morphometry (VBM) in congenitally deaf adolescents. Materials and Methods: A VBM8 methodology was applied to the T1-weighted magnetic resonance imaging (MRI) scans of eight congenitally deaf adolescents (mean age, 15.6 years) and nine adolescents with normal hearing. All MRI scans were normalized to a template and then segmented, modulated, and smoothed. Smoothed GM data were tested statistically using analysis of covariance (controlled for age, gender, and intracranial cavity volume). Results: The mean values of age, gender, total volumes of GM, and total intracranial volume did not differ between the two groups. In the auditory centers, the left anterior Heschl's gyrus and both inferior colliculi showed decreased regional GM volume in the congenitally deaf adolescents. The GM volumes of the lingual gyri, nuclei accumbens, and left posterior thalamic reticular nucleus in the midbrain were also decreased. Conclusions: The results of the present study suggest that early deprivation of auditory stimulation in congenitally deaf adolescents might have caused significant underdevelopment of the auditory cortex (left Heschl's gyrus), subcortical auditory structures (inferior colliculi), auditory gain controllers (nucleus accumbens and thalamic reticular nucleus), and multisensory integration areas (inferior colliculi and lingual gyri). These defects might be related to the absence of general auditory perception, the auditory gating system of thalamocortical transmission, and failure in the maturation of the auditory-to-limbic connection and the auditorysomatosensory-visual interconnection.

Analysis on the Theoretical Models Related to the Integration of Science and Mathematics Education: Focus on Four Exemplary Models

  • Lee, Hyon-Yong
    • 한국과학교육학회지
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    • 제31권3호
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    • pp.475-489
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    • 2011
  • The purposes of this study were to inform the exemplary models of integrated science and mathematics and to analyze and discuss their similarities and differences of the models. There were two steps to select the exemplary models of integrated science and mathematics. First, the second volume (Berlin & Lee, 2003) of the bibliography of integrated science and mathematics was analyzed to identify the models. As a second step, we selected the models that are dealt with in the School Science Mathematics journal and were cited more than three times. The findings showed that the following four exemplary theoretical models were identified and published in the SSM journal: the Berlin-White Integrated Science and Mathematics (BWISM) Model, the Mathematics/Science Continuum Model, the Continuum Model of Integration, and the Five Types of Science and Mathematics Integration. The Berlin-White Integrated Science and Mathematics (BWISM) Model focused an interpretive or framework theory for integrated science and mathematics teaching and learning. BWISM focused on a conceptual base and a common language for integrated science and mathematics teaching and learning. The Mathematics/Science Continuum Model provided five categories and ways to clarify the extent of overlap or coordination between science and mathematics during instructional practice. The Continuum Model of Integration included five categories and clarified the nature of the relationship between the mathematics and science being taught and the curricular goals for the disciplines. These five types of science and mathematics integrations described the method, type, and instructional implications of five different approaches to integration. The five categories focused on clarifying various forms of integrated science and mathematics education. Several differences and similarities among the models were identified on the basis of the analysis of the content and characteristics of the models. Theoretically, there is strong support for the integration of science and mathematics education as a way to enhance science and mathematics learning experiences. It is expected that these instructional models for integration of science and mathematics could be used to develop and evaluate integration programs and to disseminate integration approaches to curriculum and instruction.

통계적인 기법을 활용한 동질성구간에 따른 교통량 수시조사 효율화 연구 (Determination of a Homogeneous Segment for Short-term Traffic Count Efficiency Using a Statistical Approach)

  • 정유석;오주삼
    • 한국도로학회논문집
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    • 제17권4호
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    • pp.135-141
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    • 2015
  • PURPOSES: This study has been conducted to determine a homogeneous segment and integration to improve the efficiency of short-term traffic count. We have also attempted to reduce the traffic monitoring budget. METHODS: Based on the statistical approach, a homogeneous segment in the same road section is determined. Statistical analysis using t-test, mean difference, and correlation coefficient are carried out for 10-year-long (2004-2013) short-term count traffic data and the MAPE of fresh data (2014) are evaluated. The correlation coefficient represents a trend in traffic count, while the mean difference and t-score represent an average traffic count. RESULTS : The statistical analysis suggests that the number of target segments varies with the criteria. The correlation coefficient of more than 30% of the adjacent segment is higher than 0.8. A mean difference of 36.2% and t-score of 19.5% for adjacent segments are below 20% and 2.8, respectively. According to the effectiveness analysis, the integration criteria of the mean difference have a higher effect as compared to the t-score criteria. Thus, the mean difference represents a traffic volume similarity. CONCLUSIONS : The integration of 47 road segments from 882 adjacent road segments indicate 8.87% of MAPE, which is within an acceptable range. It can reduce the traffic monitoring budget and increase the count to improve an accuracy of traffic volume estimation.

Trading Mechanisms, Liquidity Risk And International Equity Market Integration

  • Kim, Kyung-Won
    • 재무관리논총
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    • 제3권1호
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    • pp.179-211
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    • 1996
  • This study examines whether trading mechanisms or market microstructures of markets have an effect on the integration issue of the international equity market. If the international equity market is integrated, identical stocks listed on different international stock exchanges should have the same rates of return, the same characteristics of stock price behavior and similar distributions of return. If different market microstructures, or trading mechanisms cause differences in characteristics of stock price behavior, those can lead to different rates of return because of different liquidity risk for the same stocks between markets. This study proposes international asset pricing with liquidity risk related to trading mechanisms. Systematic risk by itself cannot predict the sign of expected rate of return difference for the same stocks between international markets. Liquidity risk factors related to market microstructure provide explanations for the sign of rate of return differences between markets, However, liquidity risk factors related to market microstructure do not have a significant effect on the rate of return differences and sensitivity of return differences between markets, Trading mechanisms or market microstructures might not have a significant effect on the interpretation of the international equity market integration studies, if trading volume or other factors are controlled.

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슈퍼 칩 구현을 위한 헤테로집적화 기술 (Ultimate Heterogeneous Integration Technology for Super-Chip)

  • 이강욱
    • 마이크로전자및패키징학회지
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    • 제17권4호
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    • pp.1-9
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    • 2010
  • 삼차원 집적화기술의 현황과 과제 및 향후에 요구되어질 새로운 삼차원 집적화기술의 필요성에 대해 논의를 하였다. Super-chip 기술이라 불리우는 자기조직화 웨이퍼집적화 기술 및 삼차원 헤테로집적화 기술에 대해 소개를 하였다. 액체의 표면장력을 이용하여지지 기반위에 다수의 KGD를 일괄 실장하는 새로운 집적화 기술을 적용하여, KGD만으로 구성된 자기조직화 웨이퍼를 다층으로 적층함으로써 크기가 다른 칩들을 적층하는 것에 성공을 하였다. 또한 삼차원 헤테로집적화 기술을 이용하여 CMOS LSI, MEMS 센서들의 전기소자들과 PD, VC-SEL등의 광학소자 및 micro-fluidic 등의 이종소자들을 삼차원으로 집적하여 시스템화하는데 성공하였다. 이러한 기술은 향후 TSV의 실용화 및 궁극의 3-D IC인 super-chip을 구현하는데 필요한 핵심기술이다.

3-D Hetero-Integration Technologies for Multifunctional Convergence Systems

  • 이강욱
    • 마이크로전자및패키징학회지
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    • 제22권2호
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    • pp.11-19
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    • 2015
  • Since CMOS device scaling has stalled, three-dimensional (3-D) integration allows extending Moore's law to ever high density, higher functionality, higher performance, and more diversed materials and devices to be integrated with lower cost. 3-D integration has many benefits such as increased multi-functionality, increased performance, increased data bandwidth, reduced power, small form factor, reduced packaging volume, because it vertically stacks multiple materials, technologies, and functional components such as processor, memory, sensors, logic, analog, and power ICs into one stacked chip. Anticipated applications start with memory, handheld devices, and high-performance computers and especially extend to multifunctional convengence systems such as cloud networking for internet of things, exascale computing for big data server, electrical vehicle system for future automotive, radioactivity safety system, energy harvesting system and, wireless implantable medical system by flexible heterogeneous integrations involving CMOS, MEMS, sensors and photonic circuits. However, heterogeneous integration of different functional devices has many technical challenges owing to various types of size, thickness, and substrate of different functional devices, because they were fabricated by different technologies. This paper describes new 3-D heterogeneous integration technologies of chip self-assembling stacking and 3-D heterogeneous opto-electronics integration, backside TSV fabrication developed by Tohoku University for multifunctional convergence systems. The paper introduce a high speed sensing, highly parallel processing image sensor system comprising a 3-D stacked image sensor with extremely fast signal sensing and processing speed and a 3-D stacked microprocessor with a self-test and self-repair function for autonomous driving assist fabricated by 3-D heterogeneous integration technologies.

통합·이설방식의 전통시장 현대화 사업에 대한 상인과 고객의 만족도 분석 - 나주목사고을시장을 사례로 (Analysis of Satisfaction of Merchants & Customers on Facility Modernization Project by Integration & Move Method of Traditional Market - in the Case of Naju Moksagoeul Market)

  • 조진상
    • 농촌계획
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    • 제19권3호
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    • pp.75-88
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    • 2013
  • This study aims at reviewing satisfaction on facility modernization project of traditional market by case study on integration & move method of 2 markets (Seongbuk 5 day market & Geumgye daily market). Following this study, it asked 182 merchants & customers at Naju Moksagoeul Market about satisfaction and performance on integration & move and the facility modernization project of traditional markets. According to results of the survey, not only merchants but also customers are satisfied with the modernization project. But in detail, valuations between 5 days market and daily market, and between merchants and customers are different. For example, merchants regard as negative, but customers as positive about move of the markets from city to outside. About half of respondents answer that number of market visits and sales volume after move of the markets are higher than before. More than 80% of respondents answer that culture & tourism market programs are helpful to the market revitalization.

Through Silicon Stack (TSS) Assembly for Wide IO Memory to Logic Devices Integration and Its Signal Integrity Challenges

  • Shin, Jaemin;Kim, Dong Wook
    • 한국전자파학회지:전자파기술
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    • 제24권2호
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    • pp.51-57
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    • 2013
  • The current expanding mobile markets incessantly demands small form factor, low power consumption and high aggregate throughput for silicon-level integration such as memory to logic system. One of emerging solution for meeting this high market demand is 3D through silicon stacking (TSS) technology. Main challenges to bring 3D TSS technology to the volume production level are establishing a cost effective supply chain and building a reliable manufacturing processes. In addition, this technology inherently help increase number of IOs and shorten interconnect length. With those benefits, however, potential signal and power integrity risks are also elevated; increase in PDN inductance, channel loss on substrate, crosstalk and parasitic capacitance. This paper will report recent progress of wide IO memory to high count TSV logic device assembly development work. 28 nm node TSV test vehicles were fabricated by the foundry and assembled. Successful integration of memory wide IO chip with less than a millimeter package thickness form factor was achieved. For this successful integration, we discussed potential signal and power integrity challenges. This report demonstrated functional wide IO memory to 28 nm logic device assembly using 3D package architecture with such a thin form factor.