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Smart Synthetic Path Search System for Prevention of Hazardous Chemical Accidents and Analysis of Reaction Risk (반응 위험성분석 및 사고방지를 위한 스마트 합성경로 탐색시스템)

  • Jeong, Joonsoo;Kim, Chang Won;Kwak, Dongho;Shin, Dongil
    • Korean Chemical Engineering Research
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    • v.57 no.6
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    • pp.781-789
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    • 2019
  • There are frequent accidents by chemicals during laboratory experiments and pilot plant and reactor operations. It is necessary to find and comprehend relevant information to prevent accidents before starting synthesis experiments. In the process design stage, reaction information is also necessary to prevent runaway reactions. Although there are various sources available for synthesis information, including the Internet, it takes long time to search and is difficult to choose the right path because the substances used in each synthesis method are different. In order to solve these problems, we propose an intelligent synthetic path search system to help researchers shorten the search time for synthetic paths and identify hazardous intermediates that may exist on paths. The system proposed in this study automatically updates the database by collecting information existing on the Internet through Web scraping and crawling using Selenium, a Python package. Based on the depth-first search, the path search performs searches based on the target substance, distinguishes hazardous chemical grades and yields, etc., and suggests all synthetic paths within a defined limit of path steps. For the benefit of each research institution, researchers can register their private data and expand the database according to the format type. The system is being released as open source for free use. The system is expected to find a safer way and help prevent accidents by supporting researchers referring to the suggested paths.

Units' Path-finding Method Proposal for A* Algorithm in the Tilemap (타일맵에서 A* 알고리즘을 이용한 유닛들의 길찾기 방법 제안)

  • Lee Se-Il
    • Journal of the Korea Society of Computer and Information
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    • v.9 no.3
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    • pp.71-77
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    • 2004
  • While doing games, units have to find goal And according to algorism, there is great difference in time and distance. In this paper the researcher compared and described characteristics of each of the improved algorism and A* algorism by giving depth-first search, breadth-first search and distance value and then argued algorism. In addition. by actually calculating the presumed value in A* a1gorism, the researcher finds the most improved value. Finally, by means of comparison between A* algorism and other one, the researcher verified its excellence and did simple path-finding using A* algorism.

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A Study on Online Consumers′Price Sensitivity (온라인 시장에서 가격민감도에 영향을 미치는 요인에 관한 연구)

  • 송형철
    • The Journal of the Korea Contents Association
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    • v.2 no.3
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    • pp.59-69
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    • 2002
  • This article purpose are on the variables of consumer's Doe sensitivity. Our result from sets of data indicate that the web site trust, the web site interactivity and the perceived risk have an effect on price search. Our result is as follows. First, the more trust the web site, the lower the price search. Second, the more interactivity of the web site, the lower the price search. Third, the greater the depth of information at the web site, the higher the price search. forth, the higher the perceived risk, the higher the price search. Fifth, the higher the knowledge of product, the higher the price search.

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Solving the Correspondence Problem by Multiple Stereo Image and Error Analysis of Computed Depth (다중 스테레오영상을 이용한 대응문제의 해결과 거리오차의 해석)

  • 이재웅;이진우;박광일
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.19 no.6
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    • pp.1431-1438
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    • 1995
  • In this paper, we present a multiple-view stereo matching method in case of moving in the direction of optical axis with stereo camera. Also we analyze the obtainable depth precision to show that multiple-view stereo increases the virtual baseline with single-view stereo. This method decides candidate points for correspondence in each image pair and then search for the correct combinations of correspondences among them using the geometrical consistency they must satisfy. Adantages of this method are capability in increasing the accuracy in matching by using the multiple stereo images and less computation due to local processing. This method computes 3-D depth by averaging the depth obtained in each multiple-view stereo. We show that the resulting depth has more precision than depth obtainable by each independent stereo when the position of image feature is uncertain due to image noise. This paper first defines a multipleview stereo agorithm in case of moving in the direction of optical axis with stereo camera and analyze the obtainable precision of computed depth. Then we represent the effect of removing the incorrect matching candidate and precision enhancement with experimental result.

Preliminary Development of a Scale for the Measurement of Information Avoidance

  • Kap-Seon, KIM
    • Journal of Wellbeing Management and Applied Psychology
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    • v.6 no.1
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    • pp.23-31
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    • 2023
  • Purpose: The purpose of this study is a preliminary study to develop a comprehensive information avoidance scale that includes various search contexts. Research design, data and methodology: This study is a part of exploratory sequential design of mixed method for the development of information avoidance scale. Based on the themes derived from the analysis of the in-depth interview data collected in the qualitative research of the first stage of the study, 45 preliminary items on information search and avoidance were constructed. The factors related to information searching included information recognition, information seeking purpose, and information search expectations. Individual, information, time, and system factors were related to information avoidance. Pearson's correlation analysis was performed for the correlation between factor items, and Cronbach's alpha analysis was performed for the reliability analysis of the items. Exploratory factor analysis was applied to examine the construct validity of 35 items of information avoidance. Results: Among the information avoidance items, one of the less relevant among information purpose items, two information factor items, and one time factor item were excluded. Conclusions: A secondary survey should be conducted to confirm the validity and reliability of the scale composed of adjusted items (35) based on the results of exploratory factor analysis. The strength of this preliminary scale is that it was developed based on vivid qualitative data of ordinary people who had experiences of search and avoidance in various search contexts.

A study on the characteristic of problem solving process in the architectural design process (건축디자인과정에서 문제해결의 특성에 관한 연구)

  • Kim, Yong-Il;Han, Jae-Su
    • Journal of The Korean Digital Architecture Interior Association
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    • v.11 no.3
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    • pp.53-59
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    • 2011
  • In creative design, it is necessary to understand the characteristic of architectural design. In the world of design problem, a distinction can be made between those that are well-defined and those that are ill-defined. Well-defined problems are those for which the ends or goal, are already prescribed and apparent, their solution requires the provision of appropriate means. For ill-defined problems, on the other hand, both the ends and the means of solution are unknown at the outset of the problem solving exercise, at least in their entirety. Most of design problems is ill-defined, which is unknown at the beginning of the problem solving exercise. In order to solve the design problem, Designers take advantage of the search methods of problem space, such as global-search-methods(depth-first-methods, breath-first-methods), local-search-methods(generate and test, heuristics, hill-climbing, reasoning) and visual thinking, which is represented through sketching. Sketching is a real part of design reasoning and it does so through a special kind of visual imagery. Also in the design problem solving it have been an important means of problem exploration and solution generation. By sketching, they represent images held in the mind as well as makes graphic images which help generate mental images of entity that is being designed. The search methods of problem space and a visual thinking have been crucially considered in the architectural design. The purpose of this paper is to explore the property of design by means of the pre-existed-experiment data and literature research. The findings will help design the architectural design for more creative results.

Fast PU Decision Method Using Coding Information of Co-Located Sub-CU in Upper Depth for HEVC (상위깊이의 Sub-CU 부호화 정보를 이용한 HEVC의 고속 PU 결정 기법)

  • Jang, Jae-Kyu;Choi, Ho-Youl;Kim, Jae-Gon
    • Journal of Broadcast Engineering
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    • v.20 no.2
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    • pp.340-347
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    • 2015
  • HEVC (High Efficiency Video Coding) achieves high coding efficiency by employing a quadtree-based coding unit (CU) block partitioning structure and various prediction units (PUs), and the determination of the best CU partition structure and the best PU mode based on rate-distortion (R-D) cost. However, the computation complexity of encoding also dramatically increases. In this paper, to reduce such encoding computational complexity, we propose three fast PU mode decision methods based on encoding information of upper depth as follows. In the first method, the search of PU mode of the current CU is early terminated based on the sub-CBF (Coded Block Flag) of upper depth. In the second method, the search of intra prediction modes of PU in the current CU is skipped based on the sub-Intra R-D cost of upper depth. In the last method, the search of intra prediction modes of PU in the lower depth's CUs is skipped based on the sub-CBF of the current depth's CU. Experimental results show that the three proposed methods reduce the computational complexity of HM 14.0 to 31.4%, 2.5%, and 23.4% with BD-rate increase of 1.2%, 0.11%, and 0.9%, respectively. The three methods can be applied in a combined way to be applied to both of inter prediction and intra prediction, which results in the complexity reduction of 34.2% with 1.9% BD-rate increase.

Bayesian-theory-based Fast CU Size and Mode Decision Algorithm for 3D-HEVC Depth Video Inter-coding

  • Chen, Fen;Liu, Sheng;Peng, Zongju;Hu, Qingqing;Jiang, Gangyi;Yu, Mei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.4
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    • pp.1730-1747
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    • 2018
  • Multi-view video plus depth (MVD) is a mainstream format of 3D scene representation in free viewpoint video systems. The advanced 3D extension of the high efficiency video coding (3D-HEVC) standard introduces new prediction tools to improve the coding performance of depth video. However, the depth video in 3D-HEVC is time consuming. To reduce the complexity of the depth video inter coding, we propose a fast coding unit (CU) size and mode decision algorithm. First, an off-line trained Bayesian model is built which the feature vector contains the depth levels of the corresponding spatial, temporal, and inter-component (texture-depth) neighboring largest CUs (LCUs). Then, the model is used to predict the depth level of the current LCU, and terminate the CU recursive splitting process. Finally, the CU mode search process is early terminated by making use of the mode correlation of spatial, inter-component (texture-depth), and inter-view neighboring CUs. Compared to the 3D-HEVC reference software HTM-10.0, the proposed algorithm reduces the encoding time of depth video and the total encoding time by 65.03% and 41.04% on average, respectively, with negligible quality degradation of the synthesized virtual view.

A Branch-and-Bound Algorithm for U-line Line Balancing (U라인 라인밸런싱을 위한 분지한계법)

  • 김여근;김재윤;김동묵;송원섭
    • Journal of the Korean Operations Research and Management Science Society
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    • v.23 no.2
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    • pp.83-101
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    • 1998
  • Assembly U-lines are increasingly accepted in industry, especially just-in-time production systems, for the efficient utilization of workforce. In this paper, we present an integer programming formulation and a branch-and-bound method for balancing the U-line with the objective of minimizing the number of workstations with a fixed cycle time. In the mathematical model, we provide the method that can reduce the number of variables and constraints. The proposed branch-and-bound method searches the optimal solution based on a depth-first-search. To efficiently search for the optimal solutions to the problems, an assignment rule is used in the method. Bounding strategies and dominance rules are also utilized. Some problems require a large amount of computation time to find the optimal solutions. For this reason. some heuristic fathoming rules are also proposed. Extensive experiments with test-bed problems in the literature are carried out to show the performance of the proposed method. The computational results show that our method is promising in solution quality.

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미지의 공간 탐사를 위한 실시간 그래프 탐색

  • Choe, Eun-Mi;Kim, In-Cheol
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2005.05a
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    • pp.222-231
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    • 2005
  • 본 논문에서는 자율 에이전트에 의해 미지의 공간을 탐사하는 실시간 그래프 탐색 알고리즘 $DFS-RTA^{\ast}$$DFS-PHA^{\ast}$를 제안하고 그 효율성을 비교한다. 두 알고리즘들은 모두 깊이-우선 탐색(DFS)을 기초로 하고 있으며, 직전 노드로의 빠른 후진(backtrack) 을 위해 각각 실시간 최단 경로 탐색 방법인 $RTA^{\ast}$$PHA^{\ast}$를 적용하는 것이 특징이다. 본 논문에서는 대표적인 3차원 온라인 게임 환경인 Unreal Tournament 게임과 지능형 캐릭터 에이전트인 KGBot를 이용한 실험을 통해 두 탐색 알고리즘의 완전성과 효율성을 분석해본다.

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