• Title/Summary/Keyword: chaining

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Trip-Chaining Behavior and Trip Distribution Model (연쇄통행행태분석과 통행분포모형)

  • 김형진
    • Proceedings of the KOR-KST Conference
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    • 1995.02a
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    • pp.58-82
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    • 1995
  • This study providesd an empirical analysis of trip-chaining behavior and its application to transportation planning. In the empirical analysis, changes in trip-chaining patterns since 1970 have been examined and details of current trip-chaining behavior as they describe shopping trip-chaining behavior has changed. Individual trip-chaining has become longer and complex. It appears that the average number of trips per chains has substantially increased over the past 20 years. An increased number of trips in chains means fewer home-based trips. Changes in trip-chaining behavior have several consequences. Important consequences are for transportation and land-use planning. Up to now trips have been treated as if they are independent clusters of home-to-destination-to-home; this approach has not usually taken into account the trip-chaining behavior of individuals. this calls for a different approach to at least the trip generation and trip distribution part of transportation planning. In this study, application of trip-chaining behavior to trip distribution model formulation is proposed and its calibration results are presented.

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Improving Weaknesses of Local Chaining Algorithms (Local chaining 알고리즘의 단점 및 개선 방법)

  • 이선호;박근수
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.04a
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    • pp.976-978
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    • 2004
  • Chaining 알고리즘은 주어진 match 정보로부터 좋은 match 조합을 찾아내는 일종의 alignment 알고리즘으로 유전체 서열을 비교하는데 다양하게 응용되고 있다. 특히 서열 전체를 비교하는 대신 부분 서열을 비교할 때 사용할 수 있는 local chaining 알고리즘이 제안되었는데 본 논문은 이 기본적인 알고리즘이 Smith-waterman 알고리즘과 유사하며 따라서 비슷한 단점을 가지고 있음을 지적한다. 그리고 이를 해결하기 위해 X-drop과 정규화 된 정수를 고려하는 두 가지 기법을 적용하고 실험을 통해 개선 효과를 보인다.

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An Analysis on Truck Trip Chaining (화물자동차의 통행행태 분석(통행사슬 분석을 중심으로))

  • Seong, Hong-Mo;Kim, Chan-Sung;Shin, Seung-Jin
    • Journal of Korean Society of Transportation
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    • v.26 no.5
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    • pp.7-16
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    • 2008
  • There are unique aspects of truck vehicle movements compared with the personal travel in trip chaining. This paper reports an analysis on the truck vehicle trip chaining which intercity/metropolitan/intraregional trips are classified. Data collected from the travel dairy survey is used the truck trip-chaining analysis. The pattern of trip chaining classes is classified by the GIS mapping based on orgin-destination trip information. The physical index and efficiency index for each trip diary is used to the truck vehicle activity. Truck trips lengths and time differs from its truck type, service type and travel patterns. It is shown that the efficiency of the truck trip chaining depends on vehicle types and its delivery patterns. There are many other topics for research on trip chaining modeling such as the classification of trip chain, time use and mode choice by trip chaining.

Study of Hash Collision Resolution Scheme for NAND Flash Memory (NAND Flash 메모리 기반 해시 충돌 처리 기법에 관한 연구)

  • Park, Woong-Kyu;Kim, Sung-Chul;On, Byung-Won;Jung, Ho-Youl;Choi, Gyu Sang
    • IEMEK Journal of Embedded Systems and Applications
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    • v.12 no.6
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    • pp.413-424
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    • 2017
  • In this paper, we show shortcomings of separate chaining scheme by way of experiments with NAND flash memory and improve the performance with merge chaining scheme which is proposed in this paper. We explain this merge chaining scheme and explain how to improve the performance of search operation. Merge chaining scheme shows better performance at insert and search operation compare to separate chaining scheme.

A Code Block Cipher Method to Protect Application Programs From Reverse Engineering (응용프로그램 역분석 방지를 위한 코드블록 암호화 방법)

  • Jung, Dong-Woo;Kim, Hyong-Shik;Park, Joong-Gil
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.18 no.2
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    • pp.85-96
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    • 2008
  • One of the typical methods to prevent tampering and reverse engineering on executable codes is to encrypt them. This paper proposes a code block cipher method based on key chaining to encrypt the code. The block cipher by key chaining has been known to be inadequate for encrypting the code with control transfer, even though the key chaining has advantage of hiding the keys in blocks and making the individual keys different from block to block. This paper proposes a block transformation and duplication method to apply the block cipher by key chaining to the executable codes with control transfer instructions, and shows the idea works with the MIPS instruction set.

Analyzing the Characteristics of Trip Chaining Activities of the Elderly in Seoul Metropolitan Area (수도권 고령자의 통행사슬 특성에 관한 연구)

  • Lee, Hyangsook;Choo, Sangho;Kim, Jiyoon
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.13 no.2
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    • pp.68-79
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    • 2014
  • This paper analyzes the characteristics of trip chaining activities of elderly and explores temporal and spatial distribution. The research also estimates ordered probit model and binary logistic model to investigate various factors affecting trip chaining and mode choice patterns. We utilized household survey data for elderly conducted in 2006 and 2010 in Seoul metropolitan area. Research results indicate that trip chaining showed an increasing trend and simple trip chaining counts for more than 85%. GIS mapping expressed spatial distribution of trip departure and arrival areas, particularly showing regional changes in job-related trips. We also found that more factors influence trip chaining in 2010, compared with 2006, and travel cost is more sensitive than travel time in determining travel mode. The research contributes to establish transportation policies based on travel behavior of elderly in a upcoming super-aged society.

Development of an SWRL-based Backward Chaining Inference Engine SMART-B for the Next Generation Web (차세대 웹을 위한 SWRL 기반 역방향 추론엔진 SMART-B의 개발)

  • Song Yong-Uk;Hong June-Seok;Kim Woo-Ju;Lee Sung-Kyu;Youn Suk-Hee
    • Journal of Intelligence and Information Systems
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    • v.12 no.2
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    • pp.67-81
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    • 2006
  • While the existing Web focuses on the interface with human users based on HTML, the next generation Web will focus on the interaction among software agents by using XML and XML-based standards and technologies. The inference engine, which will serve as brains of software agents in the next generation Web, should thoroughly understand the Semantic Web, the standard language of the next generation Web. As abasis for the service, the W3C (World Wide Web Consortium) has recommended SWRL (Semantic Web Rule Language) which had been made by compounding OWL (Web Ontology Language) and RuleML (Rule Markup Language). In this research, we develop a backward chaining inference engine SMART-B (SeMantic web Agent Reasoning Tools -Backward chaining inference engine), which uses SWRL and OWL to represent rules and facts respectively. We analyze the requirements for the SWRL-based backward chaining inference and design analgorithm for the backward chaining inference which reflects the traditional backward chaining inference algorithm and the requirements of the next generation Semantic Web. We also implement the backward chaining inference engine and the administrative tools for fact and rule bases into Java components to insure the independence and portability among different platforms under the environment of Ubiquitous Computing.

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Scheduling Considering Bit-Level Delays for High-Level Synthesis (상위수준 합성을 위한 비트단위 지연시간을 고려한 스케줄링)

  • Kim, Ji-Woong;Shin, Hyun-Chul
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.45 no.11
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    • pp.83-88
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    • 2008
  • In this paper, a new scheduling method considering bit-level delays for high-level synthesis is proposed. Conventional bit-level delay calculation for high-level synthesis was usually limited for specific resources. However, we have developed an efficient bit-level delay calculation method which is applicable to various resources, in this research. This method is applied to scheduling. The scheduling algorithm is based on list scheduling and executes chaining considering bit-level delays. Furthermore, multi-cycle chaining can be allowed to improve performance under resource constraints. Experimental results on several well-known DSP examples show that our method improves the performance of the results by 14.7% on the average.

Study on Inference and Search for Development of Diagnostic Ontology in Oriental Medicine (한의진단 Ontology 구축을 위한 추론과 탐색에 관한 연구)

  • Park, Jong-Hyun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.23 no.4
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    • pp.745-750
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    • 2009
  • The goal of this study is to examine on reasoning and search for construction of diagnosis ontology as a knowledge base of diagnosis expert system in oriental medicine. Expert system is a field of artificial intelligence. It is a system to acquire information with diverse reasoning methods after putting expert's knowledge in computer systematically. A typical model of expert system consists of knowledge base and reasoning & explanatory structure offering conclusion with the knowledge. To apply ontology as knowledge base to expert system practically, consideration on reasoning and search should be together. Therefore, this study compared and examined reasoning, search with diagnosis process in oriental medicine. Reasoning is divided into Rule-based reasoning and Case-based reasoning. The former is divided into Forward chaining and Backward chaining. Because of characteristics of diagnosis, sometimes Forward chaining or backward chaining are required. Therefore, there are a lot of cases that Hybrid chaining is effective. Case-based reasoning is a method to settle a problem in the present by comparing with the past cases. Therefore, it is suitable to diagnosis fields with abundant cases. Search is sorted into Breadth-first search, Depth-first search and Best-first search, which have respectively merits and demerits. To construct diagnosis ontology to be applied to practical expert system, reasoning and search to reflect diagnosis process and characteristics should be considered.

Development of a Backward Chaining Inference Methodology Considering Unknown Facts Based on Backtrack Technique (백트래킹 기법을 이용한 불확정성 하에서의 역방향추론 방법에 대한 연구)

  • Song, Yong-Uk;Shin, Hyun-Sik
    • Journal of Information Technology Services
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    • v.9 no.3
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    • pp.123-144
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    • 2010
  • As knowledge becomes a critical success factor of companies nowadays, lots of rule-based systems have been and are being developed to support their activities. Large number of rule-based systems serve as Web sites to advise, or recommend their customers. They usually use a backward chaining inference algorithm based on backtrack to implement those interactive Web-enabled rule-based systems. However, when the users like customers are using these systems interactively, it happens frequently where the users do not know some of the answers for the questions from the rule-based systems. We are going to design a backward chaining inference methodology considering unknown facts based on backtrack technique. Firstly, we review exact and inexact reasoning. After that, we develop a backward chaining inference algorithm for exact reasoning based on backtrack, and then, extend the algorithm so that it can consider unknown facts and reduce its search space. The algorithm speeded-up inference and decreased interaction time with users by eliminating unnecessary questions and answers. We expect that the Web-enabled rule-based systems implemented by our methodology would improve users' satisfaction and make companies' competitiveness.