• Title/Summary/Keyword: crossing application

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Estimation of Concrete Strength Based on Artificial Intelligence Techniques (인공지능 기법에 의한 콘크리트 강도 추정)

  • 김세동;신동환;이영석;노승용;김성환
    • The Journal of the Acoustical Society of Korea
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    • v.18 no.7
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    • pp.101-111
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    • 1999
  • This paper presents concrete pattern recognition method to identify the strength of concrete by evidence accumulation with multiple parameters based on artificial intelligence techniques. At first, variance(VAR), zero-crossing(ZCR), mean frequency(MEANF), and autoregressive model coefficient(ARC) and linear cepstrum coefficient(LCC) are extracted as feature parameters from ultrasonic signal of concrete. Pattern recognition is carried out through the evidence accumulation procedure using distance measured with reference parameters. A fuzzy mapping function is designed to transform the distances for the application of the evidence accumulation method. Results(92% successful pattern recognition rate) are presented to support the feasibility of the suggested approach for concrete pattern recognition.

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Lagrangian Simulation Model of Heavy Particle Motion in a Turbulent Flow (라그랑지 관점에 입각한 난류유동장 내의 관성입자운동 모사 모델)

  • Moon, Sun;Maeng, Joo-Sung
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.15 no.1
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    • pp.241-251
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    • 1991
  • The present simulation model relies on a new approach of the heavy particle motion in a turbulent flow considering the time and space correlation to the Lagrangian point of view. The turbulent field is, here, assumed that its characteristic scales are random and follow a Poisson's distribution. Using this model, we have computed the trajectory of each particle, that is, its velocity and position at each time in order to study the dispersion of particles in a grid turbulent flow. The computed results have been compared to the corresponding experimental data. Due to the complex mechanism of turbulence and the theoretically and experimentally lacking information, we had to make some assumptions for simplifying the situation, but we have found the good agreement between simulated and measured results. In particular, the application of the present method on the Lagrangian correlation of particle provides an interesting alternative to the usual computational methods.

Application of the melanocortin 1 receptor (MC1R) gene for discrimination of Hanwoo from Holstein beef using real-time polymerase chain reaction (PCR)

  • Ra, Do-Kyung;Lee, Sung-Mo;Park, Eun-Jeong;Lee, Jung-Goo
    • Korean Journal of Veterinary Service
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    • v.30 no.4
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    • pp.557-562
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    • 2007
  • This study was carried out to discriminate Hanwoo from the milking and hybrid cattle by detection of MC1R gene related to bovine hair color. One hundred sixty six samples were collected from the abattoir (n = 106) and local market (n = 60). The beef from abattoir were originated from Hanwoo (n=27), Holstein (n=29), Hybrid (n=45) and imported cattle (n=5), respectively. The beef from market consisted of Hanwoo (n=36), Holstein (n=7) and imported ones (n=17). Commercialized screening kit (Kogenebiotec, Korea) was used for MC1R gene analysis. As a result, Hanwoo was discriminated from Holstein. However, 9 of 45 hybrid and 11 of 22 imported beef samples were indistinguishable from Hanwoo. It could be explained by second generation of crossing of Hanwoo with Holstein or the cattle with silver or yellow hair. This results suggest that additional tests as well as MC1R gene detection be needed to confirm Hanwoo beef among cattle beef.

A 'Social Justice' in Geography of Welfare (사회정의와 복지지리학에 관한 고찰)

  • Bae, Mi-Ae
    • Journal of the Korean association of regional geographers
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    • v.9 no.4
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    • pp.546-558
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    • 2003
  • Social justice has been an interest of whole geographers for almost four decades. The conception of social justice includes fairness and equity in the distribution of a wide range of attributes. The purpose of this study is to understand social justice in geography of welfare. The theories of social justice are needed to describe relationship between social justice and geography of welfare. The evaluation of spatial variations in welfare is closely associated with social justice. Equality, equity, efficiency, and fairness are the reasonable criteria to apply to the evaluation of distributions of welfare, relating to distributive(or territorial) justice. However, there are complications in the spatial application of welfare evaluation criteria, including access across space, boundary crossing and ecological fallacy.

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A Study on SFCL with IGBT Based DC Circuit Breaker in Electric Power Grid

  • Bae, SunHo;Kim, Hongrae;Park, Jung-Wook;Lee, Soo Hyoung
    • Journal of Electrical Engineering and Technology
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    • v.12 no.5
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    • pp.1805-1811
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    • 2017
  • Recently, DC systems are considered as efficient electric power systems for renewable energy based clean power generators. This discloses several critical issues that are required to be considered before the installation of the DC systems. First of all, voltage/current switching stress, which is aggravated by large fault current, might damage DC circuit breakers. This problem can be simply solved by applying a superconducting fault current limiter (SFCL) as proposed in this study. It allows a simple use of insulated-gate bipolar transistors (IGBTs) as a DC circuit breaker. To evaluate the proposed resistive type SFCL application to the DC circuit breaker, a DC distribution system is composed of the practical line impedances from the real distribution system in Do-gok area, Korea. Also, to reflect the distributed generation (DG) effects, several DC-to-DC converters are applied. The locations and sizes of the DGs are optimally selected according to the results of previous studies on DG optimization. The performance of the resistive type SFCL applied DC circuit breaker is verified by a time-domain simulation based case study using the power systems computer aided design/electromagnetic transients including DC (PSCAD/ EMTDC(R)).

Mapping of Quantitative Trait Loci Affecting Growth Traits in a Japanese Native Chicken Cross

  • Rikimaru, K.;Sasaki, O.;Koizumi, N.;Komatsu, M.;Suzuki, K.;Takahashi, Hideaki
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.10
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    • pp.1329-1334
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    • 2011
  • The Hinai-dori is a breed of chicken native to Akita Prefecture, Japan. An $F_2$ resource population produced by crossing low- and high-growth lines of the Hinai-dori breed was analyzed to detect quantitative trait loci (QTL) for growth traits. Highly significant QTLs for body weight at 10 and 14 weeks of age and average daily gain between 4 and 10 weeks and between 10 and 14 weeks of age were accordingly mapped in a common region between ADL0198 and ABR0287 on chromosome 1 and between MCW0240 and ABR0622 on chromosome 4, respectively. A significant QTL for body weight at 4 weeks of age and a significant QTL for average daily gain between 0 and 4 weeks of age were mapped for the first time to the same region flanking ABR0204 and ABR0284 on chromosome 1. These QTLs are good candidates for application in the development of marker-assisted selection strategies for increasing growth efficiencies in the Hinai-dori breed and native breeds of chickens in Asia.

An Analysis of the Vulnerable-Pedestrian Crossing Time in Test Crosswalk (설험용 횡단보도에서 교통약자 가로횡단시간 분석)

  • Kim, Tae-Ho;Hu, Uk;Hwang, Eu-Pyo;Won, Jai-Mu
    • Journal of the Korean Society of Safety
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    • v.23 no.4
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    • pp.90-98
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    • 2008
  • Presently, pedestrian's signal time models in korea are not considering Vulnerable-Pedestrian. So, the safety of Vulnerable-Pedestrian is being threatener and the number of accidents is increasing. Besides, the existing operational system for pedestrians can't offer the cross signal time in road corresponded the changing environment when the school zone is revitalized and the Silver zone is introduced for Vulnerable-Pedestrian. Conclusively, Vulnerable-Pedestrian's signal time models which are able to consider classified Vulnerable-Pedestrian speed, Vulnerable-Pedestrian perception-reaction time, Vulnerable-Pedestrian Spare(congestion-delay) time are suggested by the result of experiment in virtual crosswalk. the application of suggested models in this study to the site. It is possible to use as a basic stuff on study of pedestrian's signal time and expected to contribute the safety and mobility in future.

A Single-Stage Power Factor Correction Converter far $90-265V_{rms}$ Line Applications ($90-265V_{rms}$ 입력범위를 갖는 단일전력단 역률개선 컨버터)

  • 이준영;박희정;구관본;윤명중
    • The Transactions of the Korean Institute of Power Electronics
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    • v.5 no.5
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    • pp.508-514
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    • 2000
  • A single-stage power factor correction AC/DC converter with a simple link voltage suppressing circuit (LVSC) for the universal line application is proposed. Using this simple circuit, a low link voltage can be realized without deadbands at line zero-crossings. The proposed converter is analyzed and a prototype converter with 5V, 12A output is implemented to verify the performance. The experimental results show that the link voltage stress and efficiency are about 447V and 81%, respectively.

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Application of Geophysical Results to Designing Bridge over Large Fault (대규모 단층대를 통과하는 교량설계를 위한 물리탐사의 활용)

  • 정호준;김정호;박근필;최호식;김기석;김종수
    • Proceedings of the Korean Geotechical Society Conference
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    • 2001.03a
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    • pp.245-248
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    • 2001
  • During the core drilling for the design of a railway bridge crossing over the inferred fault system along the river, fracture zone, extends vertically more than the bottom of borehole, filled with fault gouge was found. The safety of bridge could be threatened by the excessive subsidence or the reduced bearing capacity of bedrock, if a fault would be developed under or around the pier foundation. Thus, a close examination of the fault was required to rearrange pier locations away from the fault or to select a reinforcement method if necessary. Geophysical methods, seismic reflection method and electrical resistivity survey over the water covered area, were applied to delineate the weak zone associated with the fault system. The results of geophysical survey clearly showed a number of faults extending vertically more than 50m. Reinforcement was not desirable because of the high cost and the water contamination, etc. The pier locations were thus rearranged based on the results of geophysical surveys to avoid the undesirable situations, and additional core drillings on the rearranged pier locations were carried out. The bedrock conditions at the additional drilling sites turned out to be acceptable for the construction of piers.

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Direction of Revision of College Scholastic Ability Test Through Literature Review (문헌분석을 통한 대학수학능력시험 수리영역의 개정 방향 탐색)

  • Ko, Ho-Kyoung
    • Journal of the Korean School Mathematics Society
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    • v.11 no.3
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    • pp.467-481
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    • 2008
  • This paper analysed a bulk of theses performed in various perspectives relating to College Scholastic Ability Test since 1994. Further this searched suggestions of revisions of systems about College Scholastic Ability Test along with the revised curriculum throngh this analysis of previous studies, which were categorized into 'correspondence between goal and characteristics', 'impact on education', and 'impact on society'. According to previous studies, they treat crossing application, advantage & disadvantage among optional subjects, difference in subject and content between natural science and cultural science, subjects that have to be included into College Scholastic Ability Test. This research suggests some elements and basic & fundamental information which need to be considered in the process of revising in problem making system of College Scholastic Ability Test.

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