• Title/Summary/Keyword: Transformation optimization

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Speed Optimization Design of 3D Medical Image Reconstruction System Based on PC (PC 기반의 3차원 의료영상 재구성 시스템의 고속화 설계)

  • Bae, Su-Hyeon;Kim, Seon-Ho;Yu, Seon-Guk
    • Journal of Biomedical Engineering Research
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    • v.19 no.2
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    • pp.189-198
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    • 1998
  • 3D medical image reconstruction techniques are useful to figure out complex 3D structures from the set of 2D sections. In the paper, 3D medical image reconstruction system is constructed under PC environment and programmed based on modular programming by using Visual C++ 4.2. The whole procedures are composed of data preparation, gradient estimation, classification, shading, transformation and ray-casting & compositing. Three speed optimization techniques are used for accelerating 3D medical image reconstruction technique. One is to reduce the rays when cast rays to reconstruct 3D medical image, another is to reduce the voxels to be calculated and the other is to apply early ray termination. To implement 3D medical image reconstruction system based on PC, speed optimization techniques are experimented and applied.

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An Optimization Method of Spatial Placement for Effective Vehicle Loading (효과적인 차량 선적을 위한 공간 배치의 최적화 기법)

  • Cha, Joo Hyoung;Choi, Jin Seok;Bae, You Su;Woo, Young Woon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.2
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    • pp.186-191
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    • 2020
  • In this paper, we proposed an optimization technique for efficiently placing vehicles on decks in a vehicle-carrying ship to efficiently handle loading and unloading. For this purpose, we utilized the transformation method of the XML data representing the ship's spatial information, merging and branching algorithm and genetic algorithm, and implemented the function to visualize the optimized vehicle placement results. The techniques of selection, crossover, mutation, and elite preservation, which are used in the conventional genetic algorithms, are used. In particular, the vehicle placement optimization method is proposed by merging and branching the ship space for the vehicle loading. The experimental results show that the proposed merging and branching method is effective for the optimization process that is difficult to optimize with the existing genetic algorithm alone. In addition, visualization results show vehicle layout results in the form of drawings so that experts can easily determine the efficiency of the layout results.

A study on Improving Latency-Optimized Fair Queuing Algorithm (최적 레이턴시 기반 공정 큐잉 방식의 개선에 관한 연구)

  • Kim, Tae-Joon
    • Journal of Korea Multimedia Society
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    • v.10 no.1
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    • pp.83-93
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    • 2007
  • WFQ (Weighted Fair Queuing) is the most popular fair queuing algorithm, but it had the inherent drawback of a poet bandwidth utilization, particularly under the traffic requiring a low rate but tight delay bound such as internet phone. It was recently identified that the poor utilization is mainly due to the non-optimized latency of a flow and then LOFQ(Latency-Optimized Fair Queuing) to overcome the drawback was introduced. In this paper, we improve the performance of LOFQ by introducing an occupied resource optimization function and reduce the implementation complexity of recursive resource transformation by revising the transformation scheme. We also prove the superiority of LOFQ over WFQ in terms of utilization. The simulation result shows that the improved LOFQ provides $20{\sim}30%$ higher utilization than that in the legacy LOFQ.

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Bandwidth Utilization in Latency-Optimized Fair Queuing Algorithm (최적 레이턴시 기반 공정 큐잉 알고리즘의 대역폭 이용도)

  • Kim, Tae-Joon
    • The KIPS Transactions:PartC
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    • v.14C no.2
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    • pp.155-162
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    • 2007
  • WFQ (Weighted Fair Queuing) is the most popular fair queuing algorithm, but it had the inherent drawback of a poor bandwidth utilization, particularly under the traffic requiring a low rate but tight delay bound such as internet phone, It was recently identified that the poor utilization is mainly due to non optimized latency of a flow and then LOFQ(Latency-Optimized Fair Queuing) to overcome the drawback was introduced, LOFQ was also improved through introducing an occupied resource optimization function and the implementation complexity of recursive resource transformation was reduced with revising the transformation scheme. However, the performance of LOFQ has been evaluated by means of simulation, so that there are some difficulties in evaluating the performance in the terms of the accuracy and evaluation time, In this paper, we develop how to analytically compute the bandwidth utilization in LOFQ.

New Usage of SOM for Genetic Algorithm (유전 알고리즘에서의 자기 조직화 신경망의 활용)

  • Kim, Jung-Hwan;Moon, Byung-Ro
    • Journal of KIISE:Software and Applications
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    • v.33 no.4
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    • pp.440-448
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    • 2006
  • Self-Organizing Map (SOM) is an unsupervised learning neural network and it is used for preserving the structural relationships in the data without prior knowledge. SOM has been applied in the study of complex problems such as vector quantization, combinatorial optimization, and pattern recognition. This paper proposes a new usage of SOM as a tool for schema transformation hoping to achieve more efficient genetic process. Every offspring is transformed into an isomorphic neural network with more desirable shape for genetic search. This helps genes with strong epistasis to stay close together in the chromosome. Experimental results showed considerable improvement over previous results.

Optimization of Welding Parameters for Resistance Spot Welding of TRIP Steel using Response Surface Methodology (저항 점 용접에서 반응표면분석법을 이용한 고장력 TRIP강의 최적 용접 조건 설정에 관한 연구)

  • 박현성;김태형;이세헌
    • Journal of Welding and Joining
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    • v.21 no.2
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    • pp.76-81
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    • 2003
  • Due to the environmental problem, automotive companies are trying to reduce the weight of car body. Therefore, WP(Transformation Induced Plasticity) steels, which are hish strength and ductility have been developed. The application of TRIP steel to the members has been reported to increase the energy absorption capability. Welding process is a complex process; therefore deciding the optimal welding conditions is an effective method on the basis of the experimental data. However, using a trial-and-error method from the beginning in such a wide area, in order to decide the optimal conditions requires too many numbers of experiments. To overcome these problems and to decide the optimal conditions, response surface methodology was used. Response surface methodology is a collection of mathematical and statistical techniques that are for the modeling and analysis of problems in which a response of interest is influenced by several variables and the objective is to optimize this response. The introduced method was applied to the resistance spot welding process of the TRIP steel and the welding parameters were optimized. (Received December 6, 2002)

The Optimization of Hyperbolic Settlement Prediction Method with the Field Data for Preloading on the Soft Ground (쌍곡선법을 이용한 계측 기반 연약지반 침하 거동 예측의 최적화 방안)

  • Choo, Yoon-Sik;Kim, June-Hyoun;Hwang, Se-Hwan;Chung, Choong-Ki
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.03a
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    • pp.457-467
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    • 2010
  • The settlement prediction is very important to preloading method for a construction site on a soft ground. At the design stage, however, it is hard to predict the settlement exactly due to limitations of the site survey. Most of the settlement prediction is performed by a regression settlement curve based on the field data during a construction. In Korea, hyperbolic method has been most commonly used to align the settlement curve with the field data, because of its simplicity and many application cases. The results from hyperbolic method, however, may be differed by data selections or data fitting methods. In this study, the analyses using hyperbolic method were performed about the field data of $\bigcirc\bigcirc$ site in Pusan. Two data fitting methods, using an axis transformation or an alternative method, were applied with the various data group. If data was used only after the ground water level being stabilized, fitting results using both methods were in good agreement with the measured data. Without the information about the ground water level, the alternative method gives better results with the field data than the method using an axis transformation.

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Study on Structure Design of High-Stiffness for 5 - Axis Machining Center (5축 공작기계의 고강성 구조설계에 관한 연구)

  • Hong, Jong-Pil;Gong, Byeong-Chae;Choi, Sung-Dae;Choi, Hyun-Jin;Lee, Dal-Sik
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.10 no.5
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    • pp.7-12
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    • 2011
  • This study covers the optimum design of the 5-axis machine tool. In addition, the intelligent control secures structural stability through the optimum design of the structure of the 5-axis machine center, main spindle, and the tilting index table. The big requirement, like above, ultimately leads to speed-up operation. And this is inevitable to understand the vibration phenomenon and its related mechanical phenomenon in terms of productivity and its accuracy. In general, the productivity is correlated with the operation speed and it has become bigger by its vibration scale and the operation speed so far. Vibration phenomenon and its heat-transformation of the machine is naturally occurred during the operation. If these entire machinery phenomenons are interpreted through the constructive understanding and the interpretation of the naturally produced vibration and heat-transformation, it would be very useful to improve the rapidity and its stability of the machine operation indeed. In this dissertation, the problems of structure through heating, stability, dynamic aspect and safety about intelligent 5-wheel machine tool are discovered to examine. All these discoveries are applied to the structure in order to enhance the density of it. It aims to improve the stability.

An Effective Orientation-based Method and Parameter Space Discretization for Defined Object Segmentation

  • Nguyen, Huy Hoang;Lee, GueeSang;Kim, SooHyung;Yang, HyungJeong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.12
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    • pp.3180-3199
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    • 2013
  • While non-predefined object segmentation (NDOS) distinguishes an arbitrary self-assumed object from its background, predefined object segmentation (DOS) pre-specifies the target object. In this paper, a new and novel method to segment predefined objects is presented, by globally optimizing an orientation-based objective function that measures the fitness of the object boundary, in a discretized parameter space. A specific object is explicitly described by normalized discrete sets of boundary points and corresponding normal vectors with respect to its plane shape. The orientation factor provides robust distinctness for target objects. By considering the order of transformation elements, and their dependency on the derived over-segmentation outcome, the domain of translations and scales is efficiently discretized. A branch and bound algorithm is used to determine the transformation parameters of a shape model corresponding to a target object in an image. The results tested on the PASCAL dataset show a considerable achievement in solving complex backgrounds and unclear boundary images.

Compiler Optimization for Parallelism and Locality Improvement (병렬성 및 지역성 증진을 위한 컴파일러 최적화)

  • Jim, Jin-Mi;Byeon, Seok-U;Pyo, Chang-U;Lee, Man-Ho
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.2
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    • pp.307-314
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    • 1999
  • In this paper, we study on the transformation technique of sequential programs for the purpose of 'exploiting parallelism' and 'improving locality'. Based on the analysis of loop procedures of sequential programs with the factor of dependency and locality, two transformation techniques of loop distribution and loop fusion are applied to them. Transformed programs can be easily expressed as a parallel program wit thread notation, having coarse-grain parallelism and improved locality. This means that those transformations can be useful tools for optimizing and automatic-parallelizing compiler construction. Application of those techniques to SPEC95 on a solaris machine with four SPARC processors show an improvement of execution time.

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