• 제목/요약/키워드: heuristic rule

Search Result 144, Processing Time 0.026 seconds

A Knowledge-based Design System for Injection Molding

  • Huh, Yong-Jeong
    • Journal of the Microelectronics and Packaging Society
    • /
    • v.8 no.3
    • /
    • pp.11-17
    • /
    • 2001
  • The design and manufacture of injection molded polymeric parts with desired properties is a costly process dominated by empiricism, including the repeated modification of actual tooling. This paper presents an expert design evaluation system which can predict the mechanical performance of a molded product and diagnose the design before the actual mold is machined. The knowledge-based system synergistically combines a rule-based expert system with CAE programs. Heuristic knowledge of injection molding is formalized as rules of an expert consultation system. The expert system interprets the analytical results of the process simulation, predicts the performance, evaluates the design and generates recommendations for optimal design alternatives.

  • PDF

Performance of LOB-based Emitter Localization Using Linear LSE Algorithms (선형 LSE 알고리즘을 이용한 신호원 위치 추정 성능)

  • Lee, Joon-Ho;Kim, Min-Cheol;Cho, Seong-Woo;Kim, Sang-Won
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.13 no.1
    • /
    • pp.36-40
    • /
    • 2010
  • In this paper, the well-known LOB-based emitter localization using linear LSE algorithm is numerically implemented and the heuristic guidelines for the parameter values to achieve 1% RMS error are presented. In the simulation, we changed the total observation durations for LOB measurements, time interval between successive LOB measurements and sensor trajectories. The effects of the time interval of LOB measurements, the time duration of the LOB measurements and the angle of flight path arc on the performance are illustrated. The dependence of the performance on the various parameters is investigated and rule-of-thumbs for the parameter values corresponding to 1% RMS error are presented for each simulation condition.

A Batching Problem to minimize the total Tardiness with Dynamic Arrivals (동적 도착의 총 납기 지연 최소화 문제)

  • Oh Se-Ho;Lee Keun-Boo;Yang Hee-Joon
    • Journal of Korean Society of Industrial and Systems Engineering
    • /
    • v.28 no.1
    • /
    • pp.92-96
    • /
    • 2005
  • This paper deals with a batch processor model in which the batch processing times depend on the jobs assigned to the batch. Each job has a distinct processing time which is determined as not the exact value but the range from the lower limit to the upper, which makes it possible to group several jobs into the same batch. In point of this flexibility our model can be referred to as the generalization of the bum-in model in which the upper limit of each job is unbounded. The jobs to be scheduled may be available nonsimultaneously. Therefore they have different ready times. We develop the model to describe the problem situation and the heuristic methods to minimize the total tardiness. And our batching rule is compared with other dispatching ones.

Allocation of Buffer Capacity in Automatic Transfer Line Using Robust Design Method (안정성 설계방법을 이용한 자동흐름라인의 완충재고용량 할당)

  • Seo, Sun-Keun;Chung, Won-Kee
    • IE interfaces
    • /
    • v.12 no.2
    • /
    • pp.210-221
    • /
    • 1999
  • Several researchers have previously studied the problem of allocating buffer storage to maximize the throughput rate and/or minimize the mean buffer average of a transfer line for a given total amount of buffer space. But there seems to be very little difference in performance between intuitively reasonable and optimal allocations. This paper proposes and illustrates a methodology, based on the robust design concept of Taguchi, to allocate buffer storage of long transfer lines with a given total amount of buffer capacity when up and down times follow exponential distributions, respectively. We show how this procedure using simple heuristic rule can be used for design of long transfer lines.

  • PDF

A Tabu Search Algorithm for Single Machine Scheduling Problem with Job Release Times and Sequence - dependent Setup Times (작업 투입시점과 순서 의존적인 작업준비시간이 존재하는 단일 기계 일정계획 수립을 위한 Tabu Search)

  • Shin, Hyun-Joon;Kim, Sung-Shick;Ko, Kyoung-Suk
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.27 no.2
    • /
    • pp.158-168
    • /
    • 2001
  • We present a tabu search (TS) algorithm to minimize maximum lateness on a single machine in the presence of sequence dependent setup times and dynamic job arrivals. The TS algorithm starts with a feasible schedule generated by a modified ATCS (Apparent Tardiness Cost with Setups) rule, then through a series of search steps it improves the initial schedule. Results of extensive computational experiments show that the TS algorithm significantly outperforms a well-known RHP heuristic by Ovacik and Uzsoy, both on the solutions quality and the computation time. The performance advantage is particularly pronounced when there is high competition among jobs for machine capacity.

  • PDF

A Study on the Business Value of Products Considering Cross Selling Effect (교차판매효과를 고려한 상품의 가치평가에 관한 연구)

  • Hwang, In-Soo
    • Asia pacific journal of information systems
    • /
    • v.15 no.3
    • /
    • pp.209-221
    • /
    • 2005
  • One of the most fundamental problems in business is to evaluate the value of each product. The difficulty is that the profit of one product not only comes from its own sales, but also its influence on the sales of other products, i.e., the "cross-selling effect". This study integrates a measure for cross selling and an algorithm for profit estimation. Sales transaction data and post sales survey data from on-line and off-line shopping mall is used to show the effectiveness of the method against other heuristic for profit estimation based on product-specific profitability. We show that with the use of the new method we are able to identify the cross-selling potential of each product and use the information for better product selection.

A Study on the Heuristic Solution for n/m Job-Shop Scheduling Problems of Slack Degree (Slack Degree에 의한 n/m Job-Shop 스케줄링 문제의 발견적 해법에 관한 연구)

  • 김제홍;조남호
    • Journal of Korean Society of Industrial and Systems Engineering
    • /
    • v.19 no.39
    • /
    • pp.275-284
    • /
    • 1996
  • It can be made a definition that scheduling is a imposition of machinery and equipment to perform a collection of tasks. Ultimately scheduling is an assessment of taking order for which would be perform. So it is called "sequencing" in other words. In a job shop scheduling, the main object is to making delivery in accordance with the due date and order form customer, not to producing lots of quantity with minimizing mean flow time in a given time. Actually, in a company, they concentrate more in the delivery than minimizing the mean flow time. Therefore this paper suggest a new priority dispatching rule under consideration as below in a n/m job shop scheduling problem with due date. 1. handling/transportation time, 2. the size of customer order With this algorithm, we can make a scheduling for minimizing the tardiness of delivery which satisfy a goal of production.roduction.

  • PDF

A Study on Memetic Algorithm-Based Scheduling for Minimizing Makespan in Unrelated Parallel Machines without Setup Time (작업준비시간이 없는 이종 병렬설비에서 총 소요 시간 최소화를 위한 미미틱 알고리즘 기반 일정계획에 관한 연구)

  • Tehie Lee;Woo-Sik Yoo
    • Journal of the Korea Safety Management & Science
    • /
    • v.25 no.2
    • /
    • pp.1-8
    • /
    • 2023
  • This paper is proposing a novel machine scheduling model for the unrelated parallel machine scheduling problem without setup times to minimize the total completion time, also known as "makespan". This problem is a NP-complete problem, and to date, most approaches for real-life situations are based on the operator's experience or simple heuristics. The new model based on the Memetic Algorithm, which was proposed by P. Moscato in 1989, is a hybrid algorithm that includes genetic algorithm and local search optimization. The new model is tested on randomly generated datasets, and is compared to optimal solution, and four scheduling models; three rule-based heuristic algorithms, and a genetic algorithm based scheduling model from literature; the test results show that the new model performed better than scheduling models from literature.

Development of the lift-up and procurement system for Just-in-Time in the Building Construction (건설공사의 적시생산(Just-In-Time)을 위한 양중시스템 개발)

  • Shin Bong-Soo;Kim Chang-Duk;Suh Sang-Wook;Lim Hyoung-Chul;Choi Woon-Ki
    • Korean Journal of Construction Engineering and Management
    • /
    • v.4 no.4 s.16
    • /
    • pp.182-191
    • /
    • 2003
  • The material lift-up and procurement management for high-rise buildings is complex and critical key to the success of projects. It has been hardly managed by the heuristic or rule-of-thumb techniques which are adapted in usual construction building sites. Especially in downtown high-rise residential building project sites, the limit of heuristic management techniques is critical. It has space constraint for materials loading and site transportation especially in finish work phases in which construction period diverse work trades struggle for their own material and manpower transportation. Hence, it is essential to adapt JIT(Just-In-Time) concept in these particular types of building construction project sites. According to the analysis of the case project sites, the communication and flow of relevant information regarding material lift-up and transportation in project sites is the key factor for successful performance. Therefore, this study analyzes the flow and site transportation of the key materials and provides the system, PLUTO(Procurement & Lift-Up for material Transport Optimizing system). This study also applies the system in the case site and verifies the model validation in actual project.

Air-traffic dispatching scheduling in terminal airspace (공항접근영역 항공교통 Dispatching 스케줄링 연구)

  • Jeong, Sun-Jo;Cho, Doo-Hyun;Choi, Han-Lim
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.44 no.11
    • /
    • pp.973-980
    • /
    • 2016
  • An air traffic management (ATM) has been studied in a variety of fields to utilize an air traffic capacity efficiently and solve a congested air traffic situation due to an increment of an air traffic demand. In this paper, an air traffic management, which is related with controlling and determining the sequencing of an aircraft approaching to an airport, in terminal control area is studied. This paper focuses on scheduling algorithms with a given problem for the air traffic management with operational constraints, such as a space separation, an overtaking on the same air-route, and a route merge point (a scheduling point). For a real-time calculation, the presented algorithms focus on dispatching heuristic rules which are able to assign tasks in a fast time period with an adequate performance, which can be demonstrated as a proper and realistic scheduling algorithm. A simulation result is presented to illustrate the validity and applicability of the proposed algorithm. Each scheduling rule is analyzed on the same static and dynamic air traffic flow scenario with the ATM Monte-Carlo simulation.