• Title/Summary/Keyword: performance-based optimization

Search Result 2,574, Processing Time 0.026 seconds

Traffic Signal Control Strategy for Passive Tram Signal Priority on City Arterial (도시부 간선도로의 고정식 트램 우선신호를 위한 교통신호운영 전략)

  • Jeong, Young-Je;Kim, Young-Chan;Kim, Dae-Ho
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.10 no.1
    • /
    • pp.27-41
    • /
    • 2011
  • This research proposes new tram signal coordination model, called MAXBAND MILP-Tram for a passive tram signal priority strategy. The proposed model was formulated based on the MAXBAND model that was a traditional arterial signal optimization model. The model could calculate the bandwidth solutions for both general-purpose-lane traffic and median-tram-lane traffic. Lower progression speed are applied for the tram traffic considering lower running speed and dwell time at the stations. A phase sequence procedure determines the green times and left-turn phase sequences for tram traffic in median tram lane. To estimate the performance of the MILP-Tram model, the control delay of trams were estimated using the micro simulation model, VISSIM. The analysis results showed 57 percent decrease of the tram compared to the conventional signal timing model. The delay for car, however, increased 18 percent. The sensitivity analysis indicated that the passive tram signal priority strategy using the offset and phase sequence optimization was effective in reducing the person delay under the congested traffic condition.

A fundamental study on the development of feasibility assessment system for utility tunnel by urban patterns (도심지 유형별 공동구 설치 타당성 평가시스템 개발에 관한 기초 연구)

  • Lee, Seong-Won;Sim, Young-Jong;Na, Gwi-Tae
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.19 no.1
    • /
    • pp.11-27
    • /
    • 2017
  • The road network system of major domestic urban areas such as city of Seoul was rapidly developed and regionally expanded. In addition, many kinds of life-lines such as electrical cables, telephone cables, water&sewerage lines, heat&cold conduits and gas lines were needed in order for urban residents to live comfortably. Therefore, most of the life-lines were individually buried in underground and individually managed. The utility tunnel is defined as the urban planning facilities for commonly installing life-lines in the National Land Planning Act. Expectation effectiveness of urban utility tunnels is reducing repeated excavation of roads, improvement of urban landscape; road pavement durability; driving performance and traffic flow. It can also be expected that ensuring disaster safety for earthquakes and sinkholes, smart-grind and electric vehicle supply, rapid response to changes in future living environment and etc. Therefore, necessity of urban utility tunnels has recently increased. However, all of the constructed utility tunnels are cut-and-cover tunnels domestically, which is included in development of new-town areas. Since urban areas can not accommodate all buried life-lines, it is necessary to study the feasibility assessment system for utility tunnel by urban patterns and capacity optimization for urban utility tunnels. In this study, we break away from the new-town utility tunnels and suggest a quantitative assessment model based on the evaluation index for urban areas. In addition, we also develop a program that can implement a quantitative evaluation system by subdividing the feasibility assessment system of urban patterns. Ultimately, this study can contribute to be activated the urban utility tunnel.

Spatio-temporal Mode Selection Methods of Fast H.264 Using Multiple Reference Frames (다중 참조 영상을 이용한 고속 H.264의 움직임 예측 모드 선택 기법)

  • Kwon, Jae-Hyun;Kang, Min-Jung;Ryu, Chul
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.33 no.3C
    • /
    • pp.247-254
    • /
    • 2008
  • H.264 provides a good coding efficiency compared with existing video coding standards, H.263, MPEG-4, based on the use of multiple reference frame for variable block size motion estimation, quarter-pixel motion estimation and compensation, $4{\times}4$ integer DCT, rate-distortion optimization, and etc. However, many modules used to increase its performance also require H.264 to have increased complexity so that fast algorithms are to be implemented as practical approach. In this paper, among many approaches, fast mode decision algorithm by skipping variable block size motion estimation and spatial-predictive coding, which occupies most encoder complexity, is proposed. This approach takes advantages of temporal and spatial properties of fast mode selection techniques. Experimental results demonstrate that the proposed approach can save encoding time up to 65% compared with the H.264 standard while maintaining the visual perspectives.

Utilization of Social Media Analysis using Big Data (빅 데이터를 이용한 소셜 미디어 분석 기법의 활용)

  • Lee, Byoung-Yup;Lim, Jong-Tae;Yoo, Jaesoo
    • The Journal of the Korea Contents Association
    • /
    • v.13 no.2
    • /
    • pp.211-219
    • /
    • 2013
  • The analysis method using Big Data has evolved based on the Big data Management Technology. There are quite a few researching institutions anticipating new era in data analysis using Big Data and IT vendors has been sided with them launching standardized technologies for Big Data management technologies. Big Data is also affected by improvements of IT gadgets IT environment. Foreran by social media, analyzing method of unstructured data is being developed focusing on diversity of analyzing method, anticipation and optimization. In the past, data analyzing methods were confined to the optimization of structured data through data mining, OLAP, statics analysis. This data analysis was solely used for decision making for Chief Officers. In the new era of data analysis, however, are evolutions in various aspects of technologies; the diversity in analyzing method using new paradigm and the new data analysis experts and so forth. In addition, new patterns of data analysis will be found with the development of high performance computing environment and Big Data management techniques. Accordingly, this paper is dedicated to define the possible analyzing method of social media using Big Data. this paper is proposed practical use analysis for social media analysis through data mining analysis methodology.

Bargaining Game using Artificial agent based on Evolution Computation (진화계산 기반 인공에이전트를 이용한 교섭게임)

  • Seong, Myoung-Ho;Lee, Sang-Yong
    • Journal of Digital Convergence
    • /
    • v.14 no.8
    • /
    • pp.293-303
    • /
    • 2016
  • Analysis of bargaining games utilizing evolutionary computation in recent years has dealt with important issues in the field of game theory. In this paper, we investigated interaction and coevolution process among heterogeneous artificial agents using evolutionary computation in the bargaining game. We present three kinds of evolving-strategic agents participating in the bargaining games; genetic algorithms (GA), particle swarm optimization (PSO) and differential evolution (DE). The co-evolutionary processes among three kinds of artificial agents which are GA-agent, PSO-agent, and DE-agent are tested to observe which EC-agent shows the best performance in the bargaining game. The simulation results show that a PSO-agent is better than a GA-agent and a DE-agent, and that a GA-agent is better than a DE-agent with respect to co-evolution in bargaining game. In order to understand why a PSO-agent is the best among three kinds of artificial agents in the bargaining game, we observed the strategies of artificial agents after completion of game. The results indicated that the PSO-agent evolves in direction of the strategy to gain as much as possible at the risk of gaining no property upon failure of the transaction, while the GA-agent and the DE-agent evolve in direction of the strategy to accomplish the transaction regardless of the quantity.

Optimum Drying Conditions of On-Farm Red Pepper Dryer (고추건조기의 최적운전조건)

  • Lee, Dong-Sun;Keum, Dong-Hyuk;Park, Noh-Hyun;Park, Mu-Hyun
    • Korean Journal of Food Science and Technology
    • /
    • v.21 no.5
    • /
    • pp.676-685
    • /
    • 1989
  • Optimal operating conditions of on-farm red pepper dryer were searched by using the simulation-optimization algorithm combining the drying and quality deterioration models of red pepper with Box's complex method. Determination of control variables such as air temperature, air recycle ratio and air flow rate was based on a criterion of minimizing energy consumption under the constrainst conditions that satisfied the specified color retention of carotenoids. As quality constraint was stricter, energy consumption increased and total drying time decreased with lower recycle ratio and higher air flow rate Product mixing during drying was found to be able to improve the energy efficiency and product quality. Currently used air flow rate was assessed to be increased for the optimal operation. Two stage drying at the fixed optimal air flow rate was proven to be useful means for further saying of energy consumption. In the optimal bistaged drying, the second stage began at about one third of the total drying time and low air temperature in the first stage Increased to a high value and air recycle ratio increased slightly in the second stage. Optimal control variable scheme could be explained by the dryer performance and the carotenoids destruction kinetics in red pepper drying.

  • PDF

Ad Planning Model by Comparison Challenge Approach in the e-Marketplace (e-Marketplace에서의 비교도전에 의한 광고계획 모델)

  • 이재규;이재원
    • Journal of Intelligence and Information Systems
    • /
    • v.9 no.3
    • /
    • pp.137-153
    • /
    • 2003
  • Comparison shopping is the most popular functionality in the e-Marketplace. Most of their revenue has been generated kent the Internet advertisement, but the ad earning was declined as the ad costing per action method widespread. Seller less familiar to the customer shrinks from chances for advertising and exposing their products. So, we need an efficient methodology subject to the seller's ad budget and other constraints, and it also has to increase comparison broker's earning in the e-Marketplace. Our research proposed and developed an ad planning methodology using comparison challenge approach which can be applied by 3$^{rd}$ party comparison brokers. Comparison challenge planning is organized with challenge policy of competitor level, product level and specification level. With that policies and basic challenge propositions, we measure the quantified value of functional distance between the specifications of my product and competitor's product. My product challenges the comparison using the comparative ad format to the similar but inferior competitor's product based on quantified valuation. Comparison challenge planning system has two phases of comparative value generation and optimization. We developed a prototype system and applied it to the desktop PC market of five major manufacturers. Our performance was emphasized by comparing to other comparative ad methods such as random display method and minimum distance method..

  • PDF

Joint Optimization of the Motion Estimation Module and the Up/Down Scaler in Transcoders television (트랜스코더의 해상도 변환 모듈과 움직임 추정 모듈의 공동 최적화)

  • Han, Jong-Ki;Kwak, Sang-Min;Jun, Dong-San;Kim, Jae-Gon
    • Journal of Broadcast Engineering
    • /
    • v.10 no.3
    • /
    • pp.270-285
    • /
    • 2005
  • A joint design scheme is proposed to optimize the up/down scaler and the motion vector estimation module in the transcoder system. The proposed scheme first optimizes the resolution scaler for a fixed motion vector, and then a new motion vector is estimated for the fixed scaler. These two steps are iteratively repeated until they reach a local optimum solution. In the optimization of the scaler, we derive an adaptive version of a cubic convolution interpolator to enlarge or reduce digital images by arbitrary scaling factors. The adaptation is performed at each macroblock of an image. In order to estimate the optimal motion vector, a temporary motion vector is composed from the given motion vectors. Then the motion vector is refined over a narrow search range. It is well-known that this refinement scheme provides the comparable performance compared to the full search method. Simulation results show that a jointly optimized system based on the proposed algorithms outperforms the conventional systems. We can also see that the algorithms exhibit significant improvement in the minimization of information loss compared with other techniques.

A Quantative Evaluation Method of the Quality of Natural Language Sentences based on Genetic Algorithm (유전자 알고리즘에 기반한 자연언어 문장의 정량적 질 평가 방법)

  • Yang, Seung-Hyeon;Kim, Yeong-Seom
    • Journal of KIISE:Software and Applications
    • /
    • v.26 no.11
    • /
    • pp.1372-1380
    • /
    • 1999
  • 본 논문에서는 자연언어 문장의 객관적 정량적인 질 측정 방법의 구축에 대해 설명하고, 이를 문장 퇴고 시스템의 사례에 적용해 본다. 문장의 질을 평가한다는 것은 본질적으로 주관적이고 정량화가 어려운 작업이기 때문에, 이 과정에서 질의 객관적 계량화가 가능한지 여부가 가장 중요한 문제가 된다. 이 논문에서는 이러한 문제를 해결하기 위해 유전자 알고리즘을 이용한 진화적 접근 방법을 통해 객관적이고 정량적인 질의 측정 공식을 유도하는 방법론을 제시하였다. 이 논문에서 제시한 방법론의 핵심은 간단히 말해서 사람이 행하는 정성적인 판단을, 이에 가장 근접하는 정량적 측정 체계로 전환시키는 것이라고 보면 된다. 이것을 위해 정량화 문제를 문장의 단순 언어 특징들의 변화값을 이용한 최적화 문제로 환원시키고, 다시 이 최적화 문제를 유전자 알고리즘을 이용해 해결함으로써 문제를 효과적으로 해결할 수 있었다. 실험 결과를 보면, 본 논문에서 제시한 최적화 방법은 주어진 훈련용 예제와 검증용 예제 중 각각 99.84%, 99.88%를 만족시키는 해를 찾아내었으므로 정량적 질 평가 공식의 유도에 매우 효과적임을 알 수 있었다. 또한 도출된 측정 공식을 이용해서 실제 퇴고 시스템 평가에 적용한 결과 문장 질의 측정에 매우 유용하게 이용될 수 있음을 알 수 있었다. 이와 같이 질의 정량적 평가가 가능하다는 사실이 갖는 또 한가지 중요한 의미는 최종 사용자의 구매 의사나 개발자의 공학적 의사 결정을 위한 객관적 성능 평가 자료의 제공에 이 방법이 유용하게 사용될 수 있다는 점이다.Abstract This paper describes a method of building a quantitative measure of the quality of natural language sentences, particularly produced by document revision systems. Evaluating the quality of natural language sentences is intrinsically subjective, so what is most important as to the evaluation is whether the quality can be measured objectively. To solve such problem of objective measurability, genetic algorithm, an evolutionary learning method, is employed in this paper. The underlying standpoint of this approach is that building the quality measures is a task of constructing a formulae that produces as close results as can to the qualitative decisions made by humans. For doing this, the problem of measurability has been simply reduced to an optimization problem using the change of the values of simple linguistic parameters found in sentences, and the reduced problem has been solved effectively by the genetic algorithm. Experimental result shows that the optimization task satisfied 99.84% and 99.88% of the given objectives for training and validation samples, respectively, which means the method is quite effective in constructing the quantitative measure of the quality of natural language sentences. The actual evaluation result of a revision system shows that the measure is useful to quantize the quality of sentences. Another important contribution of this measure would be to provide an objective performance evaluation data of natural language systems on a basis of which end-users and developers can make their decision to fit their own needs.

Field Scale Study for Energy Efficiency Improvement of Crematory System by the Shape Optimization of Combustion Chamber (화장로 형상 최적화를 통한 에너지효율개선을 위한 실증연구)

  • Won, Yong-Tae;Lee, Seung-Mok
    • Applied Chemistry for Engineering
    • /
    • v.30 no.5
    • /
    • pp.546-555
    • /
    • 2019
  • The purpose of this study was to improve the performance of the bogie-type crematory, which is the mainstream of domestic crematory equipment. A field scale technology was investigated via increasing the volume by changing the shape of the furnace and reducing the cremation time and saving the energy usage through the optimization of burner combustion control. First, the optimized structural design through thermal flow analysis increases the volume of the main combustion chamber by about 70%, which increases the residence time of the combustion flue gas. A designed pilot crematory was then installed and the combustion behavior was tested under various operating conditions and the optimum operating plan was derived from for each furnace shape. Based on the results, the practically applicable crematory was designed and installed at Y crematorium in the P City. Optimal combustion conditions could be derived through operating the demonstration crematory furnace. The crematory time and fuel consumption could be minimized by increasing the energy efficiency by increasing the residence time of high temperature combustion flue gas. In other words, the crematory time and fuel consumption were 38 min and $21.8Nm^3$, respectively which were shortened by 44.1 and 54.4% lower than that of the existing crematory, respectively.