• Title/Summary/Keyword: heuristic

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A Hybrid Heuristic Approach for Supply Chain Planningwith n Multi-Level Multi-Item Capacitated Lot Sizing Model (자원제약하의 다단계 다품목 공급사슬망 생산계획을 위한 휴리스틱 알고리즘)

  • Shin Hyun-Joon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.7 no.1
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    • pp.89-95
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    • 2006
  • Planning distributed manufacturing logistics is one of main issues in supply chain management. This paper proposes a hybrid heuristic approach for the Multi-Level, multi-item Capacitated Lot Sizing Problem (MLCLSP) in supply chain network. MLCLSP corresponds to a mixed integer programming (MIP) problem. With integer variable solutions determined by heuristic search, this MIP problem becomes linear program (LP). By repeatedly solving the relaxed MIP problems with a heuristic search method in a hybrid manner, this proposed approach allocates finite manufacturing resources fur each distributed facilities and generates feasible production plans. Meta heuristic search algorithm is presented to solve the MIP problems. The experimental test evaluates the computational performance under a variety of problem scenarios.

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Branch-and-Bound Based Heuristic Scheduling for the Single-Hoist and Multiple-Products Production System (단일 호이스트 생산시스템에서 다양한 주문을 처리하기 위한 분지한계 기반의 휴리스틱 일정계획)

  • Lee, Jungkoo;Kim, Jeongbae;Koh, Shiegheun
    • Journal of Korean Institute of Industrial Engineers
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    • v.42 no.3
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    • pp.173-181
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    • 2016
  • This paper deals with the single-hoist and multiple-products scheduling problem. Although a mixed integer linear programming model for the problem was developed earlier, a branch-and-bound based heuristic algorithm is proposed in this paper to solve the big-size problems in real situation. The algorithm is capable of handling problems incorporating different product types, jobs in the process, and tank capacities. Using a small example problem the procedure of the heuristic algorithm is explained. To assess the performance of the heuristic we generate a bigger example problem and compare the results of the algorithm proposed in this paper with the optimal solutions derived from the mathematical model of earlier research. The comparison shows that the heuristic has very good performance and the computation time is sufficiently short to use the algorithm in real situation.

A Heuristic for Drone-Utilized Blood Inventory and Delivery Planning (드론 활용 혈액 재고/배송계획 휴리스틱)

  • Jang, Jin-Myeong;Kim, Hwa-Joong;Son, Dong-Hoon
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.44 no.3
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    • pp.106-116
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    • 2021
  • This paper considers a joint problem for blood inventory planning at hospitals and blood delivery planning from blood centers to hospitals, in order to alleviate the blood service imbalance between big and small hospitals being occurred in practice. The joint problem is to determine delivery timing, delivery quantity, delivery means such as medical drones and legacy blood vehicles, and inventory level to minimize inventory and delivery costs while satisfying hospitals' blood demand over a planning horizon. This problem is formulated as a mixed integer programming model by considering practical constraints such as blood lifespan and drone specification. To solve the problem, this paper employs a Lagrangian relaxation technique and suggests a time efficient Lagrangian heuristic algorithm. The performance of the suggested heuristic is evaluated by conducting computational experiments on randomly-generated problem instances, which are generated by mimicking the real data of Korean Red Cross in Seoul and other reliable sources. The results of computational experiments show that the suggested heuristic obtains near-optimal solutions in a shorter amount of time. In addition, we discuss the effect of changes in the length of blood lifespan, the number of planning periods, the number of hospitals, and drone specifications on the performance of the suggested Lagrangian heuristic.

A Study on the Farming Decision-making Process of Onion and Garlic Farmers by the Perspective of Behavioral Economics (양파와 마늘 농가의 행동경제학적 영농 의사결정 과정에 관한 연구)

  • Lee, Su-Mi;Kim, Ho
    • Korean Journal of Organic Agriculture
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    • v.32 no.1
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    • pp.25-37
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    • 2024
  • This study is to apply behavioral economics-an economics that studies actual human behavior based on cognitive psychology-to the farming decision-making process of onion and garlic farmers. Of behavioral economic theories, dual system theory and prospect theory (value function), heuristic and bias were surveyed and examined in the field. The reference point of farmers was farming experience of the previous year, and so they showed reference dependence and anchoring heuristic, not rational thinking on production cost plan. And they showed status quo bias that cultivated continuously the previous year or the present crop. This status quo bias is related to loss aversion propensity. Farmers did not usually change cultivating crops, in other words, they showed diminishing sensitivity-insensitive to those that the more revenue or loss was increased. This diminishing sensitivity is related to loss aversion propensity and status quo bias. Also, farmers had representativeness heuristic because they regarded auction price of Garakdong wholesale market as the standard price level despite various prices by production region. And farmers had the affect heuristic that they depended on producers' organization data more than the state-run research institute ones about cultivation intentions and actual situations.

The Effects of Science Writing Heuristic Class on 'Seasonal Change' on Science Learning Motivation and Scientific Attitude of Elementary School Students ('계절 변화'에 대한 탐구적 과학글쓰기 수업이 초등학생들의 과학 학습동기 및 과학적 태도에 미치는 영향)

  • Kim, Soon-shik;Lee, Yong Seob
    • Journal of the Korean Society of Earth Science Education
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    • v.10 no.3
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    • pp.278-289
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    • 2017
  • The purpose of this study is to investigate the effect of science writing heuristic class on 'seasonal change' on elementary school students' science learning motivation and scientific attitude. In order to carry out this study, 49 students from 6 grade of elementary school in P metropolitan city were selected and 24 students in one class were selected as experimental group and 25 students in the other class were selected as the comparative group. The experimental group was taught science writing heuristic in 10 times classes related to the 'seasonal change' and the general classes related to the 'seasonal change' were conducted in the comparative group. Based on the results of this study, the conclusions are as follows. First, the science writing heuristic class about 'seasonal change' showed a significant effect on elementary school students' science learning motivation for science class. This is analyzed as a result of the students being more familiar with their science class through science writing heuristic class. Second, the science writing heuristic class about 'seasonal changes' showed a significant effect on elementary school students' scientific attitude. This is because the science writing heuristic class offered elementary school students an opportunity to combine their experiences in daily life with the contents of the class. Third, students' participation, satisfaction, and interest in the science writing heuristic class applied in this study were high. Therefore, it seems to be effective if the science writing heuristic class is used for science class for elementary school students.

Hybrid Heuristic Applied by the Opportunity Time to Solve the Vehicle Routing and Scheduling Problem with Time Window (시간 제약을 가지는 차량 경로 스케줄링 문제 해결을 위한 기회시간 반영 하이브리드 휴리스틱)

  • Yu, Young-Hoon;Cha, Sang-Jin;Jo, Geun-Sik
    • Journal of Intelligence and Information Systems
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    • v.15 no.3
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    • pp.137-150
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    • 2009
  • This paper proposes the hybrid heuristic method to apply the opportunity time to solve the vehicle routing and scheduling problem with time constraints(VRSPTW). The opportunity time indicates the idle time which remains after the vehicle performs the unloading service required by each customer's node. In this proposed heuristic, we add the constraints to VRSPTW model for the opportunity time. We also obtain the initial solution by applying the cost evaluation function to the insertion strategy considering the opportunity time. In addition, we improve the former result by applying the opportunity time to the tabu search strategy by swapping the customer's node. Finally, we suggest the construction strategies of initial routing which can efficiently acquire the nearest optimal solution from various types of data in terms of geographical condition, scheduling horizon and vehicle capacity. Our experiment show that our heuristic can get the nearest optimal solution more efficiently than the Solomon's I1 heuristic.

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A Study on the Relationship between Brand image, Product liking, Heuristic and Purchase Intention According to Psychological Power

  • Jin-Kwon KIM;Ik-Jun CHO;Tony-DongHui AHN
    • The Journal of Economics, Marketing and Management
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    • v.11 no.5
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    • pp.69-80
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    • 2023
  • Purpose: The purpose of this study is to identify factors that affect decision-making for e-commerce users and to present ecommerce companies with the company's strategic directions for consumer purchases. Research design, data, and methodology: In this study, a structured research model was derived to confirm the relationship between brand image, product liking, heuristic and purchase intention and the difference according to psychological power. For analysis a total of 212 valid questionnaires from e-commerce users were used. confirmatory factor analysis, correlation analysis, and structural equations were conducted to verify. Results: Both brand image and product liking had a significant effect on purchase intention as well as heuristics. However, heuristics did not affect the purchase intention. It was found that the relationship between brand image, product liking, heuristic, and purchase intention differed depending on the psychological power. Conclusions: Companies should seek ways to increase the positive brand image and likability of products so that consumers can quickly purchase products. In the relationship between brand image and heuristic, the low-psychological group has more influence on heuristic, and in case of product liking, the high-psychological group has more influence on heuristic. In the relationship between brand image and product liking for purchase intention, both in the high psychological power group affect more influence on purchase intention. Since the process of purchasing products varies depending on the consumer psychological power tendency, it is necessary to identify the characteristics of consumers and establish strategies for purchasing promotion measures.

Sustainable Closed-loop Supply Chain Model using Hybrid Meta-heuristic Approach: Focusing on Domestic Mobile Phone Industry (혼합형 메타휴리스틱 접근법을 이용한 지속가능한 폐쇄루프 공급망 네트워크 모델: 국내 모바일폰 산업을 중심으로)

  • YoungSu Yun
    • Journal of Korea Society of Industrial Information Systems
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    • v.29 no.1
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    • pp.49-62
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    • 2024
  • In this paper, a sustainable closed-loop supply chain (SCLSC) network model is proposed for domestic mobile phone industry. Economic, environmental and social factors are respectively considered for reinforcing the sustainability of the SCLSC network model. These three factors aim at minimizing total cost, minimizing total amount of CO2 emission, and maximizing total social influence resulting from the establishment and operation of facilities at each stage of the SCLSC network model. Since they are used as each objective function in modeling, the SCLSC network model can be a multi-objective optimization problem. A mathematical formulation is used for representing the SCLSC network model and a hybrid meta-heuristic approach is proposed for efficiently solving it. In numerical experiment, the performance of the proposed hybrid meta-heuristic approach is compared with those of conventional meta-heuristic approaches using some scales of the SCLSC network model. Experimental results shows that the proposed hybrid meta-heuristic approach outperforms conventional meta-heuristic approaches.

The Impact of Reading Framework as a Reading Strategy on Writing for Reflection of Middle School Students (읽기전략으로 사용된 읽기틀이 중학생들의 반성 글쓰기에 미치는 영향)

  • Sung, Hwamok;Nam, Jeonghee
    • Journal of The Korean Association For Science Education
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    • v.33 no.2
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    • pp.249-265
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    • 2013
  • The purpose of this study was to examine the influence of reading framework on writing for reflection when applied to inquiry-based Science Writing Heuristic approach. This study was conducted with 67 3rd grade middle school students. Thirty-two out of 67 students were assigned to R-SWH (Reading framework-Science Writing Heuristic) group while the other 35 students were assigned to SWH (Science Writing Heuristic) group. The R-SWH group has consistently used reading framework which the SWH group has not used when the inquiry-based science writing heuristic approach were carried out. The result of this study indicated that the R-SWH group showed a higher proportion of students who made writing for reflection by learning from reading materials than the SWH group. The R-SWH group used reading materials in order to understand the idea comprehensively and concept related to the topic the most, while the SWH group also used them for the same purpose as the R-SWH group but the ratio was less than the R-SWH group. In addition, as the learning activity has progressed, the R-SWH group showed that the proportion of students who transferred the science concept from reading materials into writing for reflection and the number of transferred concepts were higher than those of the SWH group. Therefore, the reading framework applied to inquiry-based science writing heuristic approach can facilitate a meaningful activity on reading and writing as a scaffolding to develop conceptual understanding.

VTA* Algorithm: A* Path-Finding Algorithm using Variable Turn Heuristic (VTA* 알고리즘: 가변적인 턴 휴리스틱을 적용한 A* 경로탐색 알고리즘)

  • Kim, Ji-Soo;Cho, Dae-Soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.3
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    • pp.663-668
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    • 2010
  • In driving a car, turns such as left turns, right turns, or u-turns, make the speed of the car decrease considerably. A more straight path, therefore, is probably faster to arrive at the destination than zig-zag path with same distance. In this paper, we have newly proposed the turn heuristic to make more straight path. The path navigation algorithm with turn heuristic(called as TA* algorithm) could enhance the straightness of a path by putting the turned-edges to the turn cost. It requires higher cost to use TA* algorithm than traditional A* algorithm because the straight-edge first searching have increased the search space. We have improved the TA* algorithm into the variable TA* algorithm(called as VTA* algorithm) which adopt the turn-heuristic during the a portion of the whole path.