• Title/Summary/Keyword: The weighting factor

Search Result 470, Processing Time 0.022 seconds

A Study on Site Selection for Reeve's turtle(Maunemys reevesii) Habitats Using Habitat Suitability Index (서식지 적합성 지수(HSI)를 활용한 남생이 서식지 복원 대상지 선정 방안 연구)

  • Park, Yong-Su;Chang, Min-Ho;Cha, Jin-Yeol;Cho, Dong-Gil;Kim, Seung-Hee;Lee, Sung-Woo
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.18 no.3
    • /
    • pp.109-118
    • /
    • 2015
  • This study was performed to propose the site selection plan for the restoration of the target Reeve's turtle (Maunemys reevesii) habitat and has developed the AHP model to select the optimal site for Reeve's turtle habitat restoration on the basis of the Reeve's turtle Habitat Suitability Index (HSI) items (factors and variables). The assessment areas were established by the Reeve's turtle HSI factors such as breeding space, feed, cover, water, threatening factors and others and the sub-assessment items by each assessment area were established based on the Reeve's turtle HSI variables. The weighting values of the assessment areas and items were calculated by the developed AHP method. The weighting values of the 5 assessment areas were arranged in order as breeding space(0.293), food(0.273), water(0.217), cover(0.113), and threatening factor(0.104). The final weighting values of the 17 assessment items were arranged in order of height as all kind of food(0.222), water depth(0.096), altitude of spawning ground(0.093). The scoring criteria according to the assessment items and factors were marked and applied by equal intervals considering the criteria by HSI items of the Reeve's turtle and finally the scoring criteria diagram as been proposed for the optimal site selection of the Reeve's turtle habitat restoration.

Study of Determination in Measurement System for Safely Managing Debris-Flow (안전한 토석류 관리를 위한 계측기 선정에 관한 연구)

  • Min, Dae-Hong;Yoon, Hyung-Koo
    • Journal of the Korean Society of Safety
    • /
    • v.32 no.3
    • /
    • pp.41-47
    • /
    • 2017
  • Recent studies have shown that there are various systems which can be used to monitor hazardous area in a debris flow location, but lack of methodological research on the exact location where each instrument should be installed has hindered the success of this systems. The objective of this study is to suggest the measurement system for monitoring debris-flow and propose the effective method to determine location of measurement system. Previously studied, from 1991 to 2015, were referred and the applied ratio of every instrument was investigated. The measurement information was divided into 8 categories including rainfall, debris-flow velocity, displacement, fluid pore pressure, ground vibration, image processing, impact force and peak flow depth. The result of this study revealed that the most applied instruments to be rain gauge and geophone for measuring average rainfall and ground vibration respectively. The Analytic Hierarchical Process (AHP) method was selected to determine installation location of instrument and the weighting factors were estimated through fine content, soil thickness, porosity, shear strength, elastic modulus, hydraulic conductivity and saturation. The soil thickness shows highest weights and the fine content relatively demonstrates lowest weights. The score of each position can be calculated through the weighting factors and the lowest score position can be judged as the weak point. The weak point denotes the easily affecting area and thus, the point is suitable for installing the measurement system. This study suggests a better method for safely managing the debris-flow through a precise location for installing measurement system.

Evaluation of Agricultural Drought Disaster Vulnerability Using Analytic Hierarchy Process (AHP) and Entropy Weighting Method (계층화분석 및 엔트로피 가중치 산정 방법에 따른 농업가뭄재해 취약성 평가)

  • Mun, Young-Sik;Nam, Won-Ho;Yang, Mi-Hye;Shin, Ji-Hyeon;Jeon, Min-Gi;Kim, Taegon;Lee, Seung-Yong;Lee, Kwang-Ya
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.63 no.3
    • /
    • pp.13-26
    • /
    • 2021
  • Recent drought events in the South Korea and the magnitude of drought losses indicate the continuing vulnerability of the agricultural drought. Various studies have been performed on drought hazard assessment at the regional scales, but until recently, drought management has been response oriented with little attention to mitigation and preparedness. A vulnerability assessment is introduced in order to preemptively respond to agricultural drought and to predict the occurrence of drought. This paper presents a method for spatial, Geographic Information Systems-based assessment of agricultural drought vulnerability in South Korea. It was hypothesized that the key 14 items that define agricultural drought vulnerability were meteorological, agricultural reservoir, social, and adaptability factors. Also, this study is to analyze agricultural drought vulnerability by comparing vulnerability assessment according to weighting method. The weight of the evaluation elements is expressed through the Analytic Hierarchy Process (AHP), which includes subjective elements such as surveys, and the Entropy method using attribute information of the evaluation items. The agricultural drought vulnerability map was created through development of a numerical weighting scheme to evaluate the drought potential of the classes within each factor. This vulnerability assessment is calculated the vulnerability index based on the weight, and analyze the vulnerable map from 2015 to 2019. The identification of agricultural drought vulnerability is an essential step in addressing the issue of drought vulnerability in the South Korea and can lead to mitigation-oriented drought management and supports government policymaking.

Evaluation of Optimum Genetic Contribution Theory to Control Inbreeding While Maximizing Genetic Response

  • Oh, S.H.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.25 no.3
    • /
    • pp.299-303
    • /
    • 2012
  • Inbreeding is the mating of relatives that produce progeny having more homozygous alleles than non-inbred animals. Inbreeding increases numbers of recessive alleles, which is often associated with decreased performance known as inbreeding depression. The magnitude of inbreeding depression depends on the level of inbreeding in the animal. Level of inbreeding is expressed by the inbreeding coefficient. One breeding goal in livestock is uniform productivity while maintaining acceptable inbreeding levels, especially keeping inbreeding less than 20%. However, in closed herds without the introduction of new genetic sources high levels of inbreeding over time are unavoidable. One method that increases selection response and minimizes inbreeding is selection of individuals by weighting estimated breeding values with average relationships among individuals. Optimum genetic contribution theory (OGC) uses relationships among individuals as weighting factors. The algorithm is as follows: i) Identify the individual having the best EBV; ii) Calculate average relationships ($\bar{r_j}$) between selected and candidates; iii) Select the individual having the best EBV adjusted for average relationships using the weighting factor k, $EBV^*=EBV_j(1-k\bar{{r}_j})$ Repeat process until the number of individuals selected equals number required. The objective of this study was to compare simulated results based on OGC selection under different conditions over 30 generations. Individuals (n = 110) were generated for the base population with pseudo random numbers of N~ (0, 3), ten were assumed male, and the remainder female. Each male was mated to ten females, and every female was assumed to have 5 progeny resulting in 500 individuals in the following generation. Results showed the OGC algorithm effectively controlled inbreeding and maintained consistent increases in selection response. Difference in breeding values between selection with OGC algorithm and by EBV only was 8%, however, rate of inbreeding was controlled by 47% after 20 generation. These results indicate that the OGC algorithm can be used effectively in long-term selection programs.

Learning Heuristics for Tactical Path-finding in Computer Games (컴퓨터 게임에서 전술적 경로 찾기를 위한 휴리스틱 학습)

  • Yu, Kyeon-Ah
    • Journal of Korea Multimedia Society
    • /
    • v.12 no.9
    • /
    • pp.1333-1341
    • /
    • 2009
  • Tactical path-finding in computer games is path-finding where a path is selected by considering not only basic elements such as the shortest distance or the minimum time spend but also tactical information of surroundings when deciding character's moving trajectory. One way to include tactical information in path-finding is to represent a heuristic function as a sum of tactical quality multiplied by a weighting factor which is.. determined based on the degree of its importance. The choice of weighting factors for tactics is very important because it controls search performance and the characteristic of paths found. In this paper. we propose a method for improving a heuristic function by adjusting weights based on the difference between paths on examples given by a level designer and paths found during the search process based on the CUITent weighting factors. The proposed method includes the search algorithm modified to detect search errors and learn heuristics and the perceptron-like weight updating formular. Through simulations it is demonstrated how different paths found by tactical path-finding are from those by traditional path-finding. We analyze the factors that affect the performance of learning and show the example applied to the real game environments.

  • PDF

Weighting-Factored Evaluation Method for Determination of Seismic Retrofitting Schemes for Existing Bridges (기존 도로교의 내진성능향상 방법 선정을 위한 가중치 평가기법)

  • Ha, Dong-Ho;Lee, Ji-Hoon;Park, Kwang-Soon;Lee, Yong-Jae
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.11 no.3 s.55
    • /
    • pp.43-52
    • /
    • 2007
  • This study suggests a method to determine optimal seismic retrofitting schemes for existing bridges based on weighting-factored evaluation. According to the recognition for potential seismic risk, various kinds of retrofitting methods are applied to improve the seismic performance of existing bridges. However, the relevant technique is not available to select optimal retrofitting scheme for bridges now. This suggested method weights five factors, structural compatibility, economic efficacy, environmental factor, consturctability and maintenance, and draws out optimal seismic retrofitting schemes. The application of the developed method to one hundred sixty existing bridges verifies the adaptability of this method. As a result, this study provides an idealized retrofitting schemes, and the suggested method could be a guideline to determine the more cost-effective and optimal retrofitting schemes for existing bridges in Korea.

Development of a Decision Making Model for Efficient Rehabilitation of Sewer System (효율적인 하수관거 개량을 위한 의사결정모형의 개발)

  • Lee, Jung-Ho;Jun, Hwan-Don;Joo, Jin-Gul;Kim, Joong-Hoon
    • Journal of Korea Water Resources Association
    • /
    • v.41 no.2
    • /
    • pp.127-135
    • /
    • 2008
  • The objective of sewer rehabilitation is to improve its function while eliminating inflow/infiltration (I/I) and insufficient carrying capacity (ICC). Such rehabilitation efforts, however, have not been particularly successful due to a lack of sewer data and unsystematic field practices. The present study aimed to solve these problems by developing a decision making model consisting of two models: the rehabilitation weighting model (RWM) and the rehabilitation priority model (RPM). In RWM, the I/I of each pipe in a drainage district is estimated according to various defects, with each defect given an individual weighting factor using an analytic hierarchy process (AHP). RPM determines the optimal rehabilitation priority (ORP) using a genetic algorithm (GA). The developed models can be used to overcome the problems associated with unsystematic practices and, in practice, as a decision making tool for urban sewer system rehabilitation.

Estimation of Optimal Control Parameters and Design of Hybrid Fuzzy Controller by Means of Genetic Algorithms (유전자 알고리즘에 의한 HFC의 최적 제어파라미터 추정 및 설계)

  • Lee, Dae-Keun;Oh, Sung-Kwun;Jang, Sung-Whan;Kim, Yong-Soo
    • The Transactions of the Korean Institute of Electrical Engineers D
    • /
    • v.49 no.11
    • /
    • pp.599-609
    • /
    • 2000
  • The new design methodology of a hybrid fuzzy controller by means of the genetic algorithms is presented. First, a hybrid fuzzy controller(HFC) related to the optimal estimation of control parameters is proposed. The control input for the system in the HFC combined PID controller with fuzzy controller is a convex combination of the FLC's output and PID's output by a fuzzy variable, namely, membership function of weighting coefficient. Second, an auto-tuning algorithms utilizing the simplified reasoning method and genetic algorithms is presented to automatically improve the performance of hybrid fuzzy controller. Especially, in order to auto-tune scaling factors and PID parameters of HFC using GA, three kinds of estimation modes such as basic, contraction, and expansion mode are effectively utilized. The proposed HFC is evaluated and discussed to show applicability and superiority with the and of three representative processes.

  • PDF

Rotor Performance Optimization of the Canard Rotor Wing Aircraft (Canard Rotor Wing 항공기의 로터 성능 최적화 연구)

  • Jeon, Kwon-Su;Lee, Jae-Woo;Byun, Yung-Hwan;Yu, Yung H.
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.36 no.2
    • /
    • pp.105-114
    • /
    • 2008
  • In this study, the sizing and performance analysis program is developed for the canard rotor wing(CRW) aircraft which operates in dual modes (fixed wing mode and rotary wing mode). The developed program is verified for both fixed wing and rotary wing modes using the existing aircraft data and the design optimization formulation is made to perform the reconnaissance mission. For the canard rotor wing aircraft optimization , multi-objective function is constructed to consider both the fixed wing mode and rotary wing mode the weighting factor. For six design cases with different weighting factors and different design constraints, the optimization is performed and improved rotor design results are derived.

Priority analysis of NCS based vocational core competency of dental hygienists in Gwangju (광주광역시 치과위생사의 NCS 기반 직업기초능력 우선순위 분석)

  • Hong, Nam-Hee
    • Journal of Korean society of Dental Hygiene
    • /
    • v.16 no.3
    • /
    • pp.337-346
    • /
    • 2016
  • Objectives: This study aims to investigate and analyzed the priority of vocational core competency factors in dental hygienists in Gwangju. Methods: Expert survey was conducted and Analytic Hierarchy Process(AHP) was applied to evaluate the weighting factors. First, we established the vocational core competency defined in NCS as AHP analysis model. The vocational core competency has 10 categories and 34 sub-categories. Secondly, AHP survey was conducted by 195 dental hygienists in Gwangju. Finally, the weights representing relative importance of each factor were calculated by using AHP method. Results: The AHP analysis on 10 categories showed that the weighting of interpersonal skills(0.165) was higher than any other categories while that of numeracy(0.035) was at the bottom, and the analysis on sub-categories revealed that the most important factors in each categories included the teamwork skills(interpersonal skills), problem-solving capability(problem-solving skills), listening skills(communication skills), ethical community(professional ethics), ability to understand business(ability to understand organizational structure), applicable technical skills(technical skills), self-management skills(self-development capability), information processing capabilities(information capacity), ability to manage time(resource management capabilities) and basic math skills(numeracy). Conclusions: The results in this study can be used as basic data for the development of liberal arts curriculum for dental hygiene education.