• Title/Summary/Keyword: "공간전향(空間轉向)"

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Planning Graph Heuristics for Forward State-Space Planning (전향 상태 공간 계획을 위한 계획 그래프 휴우리스틱)

  • Shin, Haeng-Chul;Kim, Man-Soo;Kim, In-Cheol
    • Proceedings of the Korean Information Science Society Conference
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    • 2006.10b
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    • pp.264-268
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    • 2006
  • Graphplan 계획기에서 유래된 계획 그래프는 탐색에 매우 유용한 휴우리스틱을 손쉽게 얻을 수 있는 수단이다. 본 논문에서는 전향 상태 공간 계획방식을 정의한 뒤, 이 계획방식에 적용 가능한 계획 그래프 기반의 휴우리스틱 계산법들을 소개한다. 또 본 논문에서는 각 휴우리스틱 계산법이 갖는 특징을 정리하고 이들이 계획생성에 미치는 효과를 실험을 통해 비교, 분석해본다. 또한 이러한 전향 상태 공간 탐색 알고리즘과 휴우리스틱 계산법을 토대로 본 연구에서는 전향 상태 공간 계획기인 JPLAN을 구현하였고 그 구조에 대해 설명한다.

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"空間轉向"与叙事空間

  • Jo, Bin;Eom, Yeong-Uk
    • 중국학논총
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    • no.66
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    • pp.1-13
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    • 2020
  • After the "spatial turn" space narrative has become the hottest "doctrine". Howe er, the current space narrative to a bottleneck stage, a variety of reasons. "Spatial turn" of the modern trend of thought has a unshirkable responsibility. Has been, scholars turned to "empty" the complex relationship between space narrative and, type of narrative space narrative theory problem also not too clear by the noun, the term textual research, narrative of space studies provide some of the necessary theoretical support, to promote the healthy de elopment of the research on novel narrative space.

An Estimate of Image Quality and Radiation Doses of Coronary Artery in MDCT Using Prospective and Retrospective ECG Gating Scan Mode (MDCT 관상동맥 조영 검사에서 전향적 동조화 및 후향적 동조화 기법의 화질과 선량 관계)

  • Oh, Jong-Kap
    • Journal of radiological science and technology
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    • v.34 no.4
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    • pp.315-321
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    • 2011
  • The goal of this study is to reduce patient exposure dose by providing image quality and radiation dose according to inspection methods. Volume Computed Tomography Dose Index(CTDIvol) and Dose Length Product(DLP) of prospective and retrospective ECG gating snapshot segment of Coronary CT angiography(CTA) were measured each snapshot segment methods. CT number, noise, uniformity, and resolution were also measured using phantom under the same condition of coronary CTA. The results showed that CT number, noise, uniformity and resolution are similar to each other. In terms of CTDIvol and DLP, however, measurement dose of prospective ECG gating snapshot segment was lower than the retrospective case by 37.5% and 40.3%. Therefore, it is highly recommended that in the coronary CTA, prospective ECG gating scan mode should be chosen to reduce patient dose.

Design and Implementation of a Hybrid Spatial Reasoning Algorithm (혼합 공간 추론 알고리즘의 설계 및 구현)

  • Nam, Sangha;Kim, Incheol
    • Journal of KIISE
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    • v.42 no.5
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    • pp.601-608
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    • 2015
  • In order to answer questions successfully on behalf of the human contestant in DeepQA environments such as 'Jeopardy!', the American quiz show, the computer needs to have the capability of fast temporal and spatial reasoning on a large-scale commonsense knowledge base. In this paper, we present a hybrid spatial reasoning algorithm, among various efficient spatial reasoning methods, for handling directional and topological relations. Our algorithm not only improves the query processing time while reducing unnecessary reasoning calculation, but also effectively deals with the change of spatial knowledge base, as it takes a hybrid method that combines forward and backward reasoning. Through experiments performed on the sample spatial knowledge base with the hybrid spatial reasoner of our algorithm, we demonstrated the high performance of our hybrid spatial reasoning algorithm.

SQUERY : A Spatial Query Processor with Spatial Reasoning and Geometric Computation (SQUERY : 공간 추론과 기하학적 연산 기능을 포함한 공간 질의 처리기)

  • Kim, Jongwhan;Kim, Incheol
    • KIISE Transactions on Computing Practices
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    • v.21 no.7
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    • pp.452-457
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    • 2015
  • In this paper, we propose a spatial query processor, SQUERY, which can derive rich query results through spatial reasoning on the initial knowledge base, as well as, process both qualitative and quantitative queries about the topological and directional relationships between spatial objects. In order to derive richer query results, the query processor expands the knowledge base by applying forward spatial reasoning into the initial knowledge base in a preprocessing step. The proposed query processor uses not only qualitative spatial knowledge describing topological/directional relationship between spatial objects, but also utilizes quantitative spatial knowledge including geometric data of individual spatial objects through geometric computation. The results of an experiment with the OSM(Open Street Map) spatial knowledge base demonstrates the high performance of our spatial query processing system.

Tabu Search using Balanced Neighborhood Production Strategy (균형 있는 이웃 해 생성 전략을 통한 타부 탐색)

  • Jeon, Dae-Seuk;Jeon, Hyang-Sin;Kwon, Kye-Ho
    • Annual Conference of KIPS
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    • 2003.11b
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    • pp.789-792
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    • 2003
  • 타부 탐색은 타부 전략 기법과 최급 강하 알고리즘이 결합된 알고리즘이다. 이는 한번 방문한 해는 다시 방문하지 않음으로써 지역 최적해에 수렴하지 않고 새로운 방향으로 움직이게 하여 공간 탐색 능력 효율을 높인다. 그러나 기존의 타부 탐색에서 이웃 해를 생성하는 방법에 따라 성능이 많이 좌우된다. 좋지 않은 이웃 해를 생성하는 탐색에서는 얻고자 하는 최적해에 수렴하는 시간이 많이 걸린다. 따라서 이웃 해를 생성할 때 해밍 거리를 고려하여 균형 있는 이웃 해론 생성하고, 해 공간은 탐색함으로써 우수한 최적해를 얻게 됨을 본 논문에서는 보여주고 있다. 이는 다양성도 보장되므로 최적해에 수렴해 가는 속도 또한 빠른 것을 보여주고 있다.

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A Three-Dimensional Galerkin-FEM Model with Density Variation (밀도 변화를 포함하는 3차원 연직함수 전개모형)

  • 이호진;정경태;소재귀;강관수;정종율
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.8 no.2
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    • pp.123-136
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    • 1996
  • A three-dimensional Galerkin-FEM model which can handle the temporal and spatial variation of density is presented. The hydrostatic approximation is used and density effects are included by means of conservation equation of heat and the equation of state. The finite difference grids are used in the horizontal plane and a set of linear-shape functions is used for the vertical expansion. The similarity transform is introduced to solve resultant matrix equations. The proposed model was first applied to the density-driven circulation in an idealized basin in the presence of the heat exchange between the air and the sea. The advection terms in the momentum equation were ignored, while the convection terms were retained in the heat equation. Coefficients of the vertical eddy viscosity and diffusivity were fixed to be constant. Calculation in a non-rotating idealized basin shows that the difference in heat capacity with depth gives rise to the horizontal gradient of temperature. Consequently, there is a steady new in the upper layer in the direction of increasing depth with compensatory counter flow .in the lower layer. With Coriolis force, geostrophic flow was predominant due to the balance between the pressure gradient and the Coriolis force. As a test in region of irregular topography, the model is applied to the Yellow Sea. Although the resultant flow was very complex, the character of the flow Showed to be geostrophic on the whole.

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Simple Robust Digital Position Control Algorithm of BLDD Motor using Neural Network with State Feedback (상태궤환과 신경망을 이용한 BLDD Motor의 간단한 강인 위치 제어 알고리즘)

  • 고종선;안태천
    • The Transactions of the Korean Institute of Power Electronics
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    • v.3 no.3
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    • pp.214-221
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    • 1998
  • A new control approach using neural network for the robust position control of a BRUSHLESS direct drive(BLDD) motor is presented. The linear quadratic controller plus feedforward neural network is employed to obtain the robust BLDD motor system approximately linearized using field-orientation method for an AC servo. The neural network is trained in on-line phases and this neural network is composed by a feedforward recall and error back-propagation training. Since the total number of nodes are only eight, this system will be easily realized by the general microprocessor. During the normal operation, the input-output response is sampled and the weighting value is trained by error back-propagation at each sample period to accommodate the possible variations in the parameters or load torque. And the state space analysis is performed to obtain the state feedback gains systematically. In addition, the robustness is also obtained without affecting overall system response.

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Research on the Value Shift of Ne zha's Character Image in Different Periods : Take Ne Zha : I am the destiny(2019) and Ne Zha Conquers the Dragon King(1979) as Examples (시기별 나타 캐릭터의 가치전향 연구- <나타지마동강세(2019)> <나타요해(1979)>를 중심으로 -)

  • Wang, Xin-Xin
    • Journal of Korea Entertainment Industry Association
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    • v.14 no.7
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    • pp.239-249
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    • 2020
  • Ne Zha: I am the destiny(2019)and Ne Zha Conquers the Dragon King(1979)as animated films based on the theme of Ne zha in different eras and contexts, reflecting the value and significance of different artistic images of Ne zha, The study of the value turn in the character image of Ne zha reflects the different styles of artistic images of Ne zha. This thesis attempts to interpret the changing values behind the different artistic expressions of the Ne zha character in different films. The transformation of Ne zha's image from good to evil, and the shift from the idea of "submit to the will of heaven" to the idea of "taking one's destiny into one's own hands" reflect the different values and meanings of Ne zha's image in different eras. Each film is distinctly contemporary, and Ne Zha: I am the destiny is an innovative and in-depth look at the character of Ne zha in the new era of cinema. There are many forms of artistic expression, and these differences greatly increase the appeal of Ne zha's artistic image, making Chinese animation films more space and value for development.

Regression Neural Networks for Improving the Learning Performance of Single Feature Split Regression Trees (단일특징 분할 회귀트리의 학습성능 개선을 위한 회귀신경망)

  • Lim, Sook;Kim, Sung-Chun
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.1
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    • pp.187-194
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    • 1996
  • In this paper, we propose regression neural networks based on regression trees. We map regression trees into three layered feedforward networks. We put multi feature split functions in the first layer so that the networks have a better chance to get optimal partitions of input space. We suggest two supervised learning algorithms for the network training and test both in single feature split and multifeature split functions. In experiments, the proposed regression neural networks is proved to have the better learning performance than those of the single feature split regression trees and the single feature split regression networks. Furthermore, we shows that the proposed learning schemes have an effect to prune an over-grown tree without degrading the learning performance.

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