• Title/Summary/Keyword: time constraint

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Outfitting and Painting Scheduling for Shipbuilding Using Constraint Satisfaction (제약 만족 기법을 이용한 기관의장과 선행도장의 일정계획)

  • Kim, Ki-Dong;Lee, Bo-Hurn
    • Journal of Industrial Technology
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    • v.26 no.A
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    • pp.173-180
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    • 2006
  • Scheduling for shipbuilding processes has many alternative solutions since it has long time horizon and handles many jobs. In this paper, an shipbuilding scheduling system for outfitting and painting is presented based on constraint satisfaction techniques(CST). We provide a field based model and an efficient solution methodology by using ILOG Scheduler and Solver. ILOG Solver support extensive optimization goals easily. We do verify the improvement and efficiency of the schedule generated by the scheduling system presented in this paper.

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Adaptive Control Constraint System through Current Monitoring of Spindle in NC Lathe Process (NC 선반공정에서 주축 전류 모니터링을 통한 구속적응제어 시스템)

  • 신동수
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1999.10a
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    • pp.27-33
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    • 1999
  • In order to regulate cutting force at a desired level during NC lathe process, a feedrate override Adaptive Control Constraint system was developed. Nonlinear model of the cutting process was linearized as an adaptive model with a time varing process parameter. Performance of the ACC system was confirmed on the NC lathe equipped with the developed NC system through a large amount of experiment.

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A CONSUMPTION, PORTFOLIO AND RETIREMENT CHOICE PROBLEM WITH NEGATIVE WEALTH CONSTRAINTS

  • ROH, KUM-HWAN
    • Journal of the Chungcheong Mathematical Society
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    • v.33 no.2
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    • pp.293-300
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    • 2020
  • In this paper we study an optimal consumption, investment and retirement time choice problem of an investor who receives labor income before her voluntary retirement. And we assume that there is a negative wealth constraint which is a general version of borrowing constraint. Using convex-duality method, we provide the closed-form solutions of the optimization problem.

A Study on Scheduling Considering Delivery and Production Efficiency in the JIT Systems (적시생산시스템에서 납기와 생산효율성을 고려한 Scheduling)

  • Kim, Jung
    • Journal of Industrial Convergence
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    • v.5 no.2
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    • pp.21-32
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    • 2007
  • This paper deals with the sequencing problem in the operation of the manufacturing systems with the constraint of buffer capacity. Some of studies for this theme have been progressed for several years. And then most of them considered only one objective, such as maximum lateness, machine utilization, makespan, mean flowtime and so on. This study deal with two objectives of the delivery for customers and the idle time of machines for producers. For the decision of sequence, the utility function is used. The developed heuristic algorithm presents a good solution. Through a numerical example, the procedures of the job sequencing is explained.

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Generalized Guidance Law with Control Time Constraint for Exoatmospheric Target Interception (외기권 표적 요격을 위한 제어시간 구속조건을 가지는 일반화된 유도법칙)

  • Park, Bong-Gyun;Kim, Tae-Hun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.46 no.10
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    • pp.814-822
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    • 2018
  • This paper proposes a guidance law for missiles with control time constraint. Because the proposed guidance law is based on a time-to-go polynomial, it has a generalized form. Also, acceleration of the proposed law converges to zero at the end of the control time, which reduces the sensitivity to the time-to-go estimation error and can increase the flight stability when the separation of the missile appears. A prediction method of the time-to-go is proposed for implementing the proposed law, and the possibility of application to the midcourse and terminal guidance phases is dealt with for exoatmospheric interception. The characteristics and performance of the proposed law are analyzed throughout various simulations.

Effects of Upper Extremity Exercise Training Using Biefeedback and Constraint-induced Movement on the Upper Extremity Function of Hemiplegic Patients (바이오피드백과 건측 억제유도 운동을 이용한 상지운동훈련이 편마비 환자의 상지기능에 미치는 효과)

  • 김금순;강지연
    • Journal of Korean Academy of Nursing
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    • v.33 no.5
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    • pp.591-600
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    • 2003
  • Purpose: The purpose of this study was to investigate the effects of exercise training using biofeedback and constraint-induced movement on the upper extremity function of hemiplegic patients. Method: A non-equivalent pretest-posttest design was used. Study subjects were a conveniently selected group of 40 hemiplegic patients(20 experimental subjects, 20 control subjects) who have been enrolled in two community health centers. After biofeedback training the subjects of experimental group were given constraint-induced movement, involving restraint of unaffected U/E in a sling for about 6 hours in a day over a period of two weeks, while at the same time intensively training the affected U/E. Outcomes were evaluated on the basis of the VIE motor ability(hand function, grip power, pinch power, U/E ROMs), and motor activity(amount, quality). Result: 1. After 2 weeks of treatment, the motor abilities of affected U/E(hand function, grip power, pinch power, ROMs of wrist flexion, elbow flexion and shoulder flexion/extension) were significantly higher in subjects who participated in exercise training than in subjects in the control group with no decrement at 4-week follow-up. However, there was no significant difference in wrist extension between experimental or control group. 2. After 2 weeks of treatment, the amount of use and the quality of motor activity of affected U/E were significantly higher in subjects who participated in exercise training than in subjects in the control group with no decrement at 4-week follow-up. Conclusion: The above results state that exercise training using biofeedback and constraint-induced movement could be an effective intervention for improving U/E function of chronic hemiplegic patients. Long-term studies are needed to determine the lasting effects of constraint-induced movement.

Applying Theory of Constraint on Logistic Management in Large Scale Construction Sites - A Case Study of Steel Bar in TFT-LCD Factory Build-Up

  • Huang, Chih-Yao;Chen, Ching-Piao;Li, Rong-Kwei;Tsai, Chih-Hung
    • International Journal of Quality Innovation
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    • v.9 no.1
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    • pp.68-93
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    • 2008
  • The steel bars account for a high percentage of material costs for the current construction projects. At the present time, most of the construction projects for the factories of thin-film transistor liquid crystal display (TFT-LCD) complete the transactions of steel bars when the suppliers ship the steel bars to the temporary storage/processing sites. This paper applies the buy-in concept in the Theory of Constraint (TOC) on the supply chain of steel bars. In this study, suppliers are required to establish warehouses at the construction sites and complete the transactions when the formed and processed steel bars are shipped into the factory sites. The aim is to find a win-win solution to meet with the expectations from constructors as they hope that there is no need to build up inventories but supply is ready at any time. Also, this paper compares and analyzes the traditional supply/inventory model of steel bars and the Demand-Pull (D-P) model under the TOC framework. It is proved that Vendor Management Inventory (VMI) in the D-P model is able to more effectively manage steel bars as a material.

Modified constraint-Induced Movement Therapy (CIMT) for the Elderly With Parkinson's Disease: A Preliminary Study (파킨슨병 노인을 위한 수정된 강제-유도운동치료: 사전연구)

  • Hwang, Su-Jin;Hong, Young-Ju;Yoo, In-Gyu;Jeon, Hye-Seon
    • Physical Therapy Korea
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    • v.16 no.1
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    • pp.70-78
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    • 2009
  • This study was designed to examine a 3-week modified constraint-induced movement therapy (CIMT) to the less-affected arm of patients with Parkinson's disease (PD) would improve function of the more-affected arm in PD. The subjects were 6 institutional older adults with PD and clients of the social welfare facilities. The subjects (2 men, 4 women) ranged in age from 66 to 90 years (mean age 77.2 yrs). Three clinical tests were used to determine the improvement of functional activity between before and after modified CIMT. The tests included Unified Parkinson's Disease Rating Scale (UPDRS). Wolf Motor Function Test (WMFT), and Action Research Arm Test (ARAT). There were significantly differences after the modified CIMT for time performance in WMFT and pinch in ARAT (p<.05), No significant difference was noted after the modified CIMT for UPDRS and functional ability scale in WMFT. Therefore, the modified CIMT might improve time performance and is available to therapeutic program helping them improve functional ability for upper extremity in Parkinson's disease.

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Time-Optimal Power Control for KMRR Using Reactivity Constraint Method (반응도 제한법에 의한 KMRR의 시간 최적 출력 제어)

  • Lee, Byung-Ill;Kim, Myung-Hyun
    • Nuclear Engineering and Technology
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    • v.23 no.1
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    • pp.30-40
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    • 1991
  • For automatic power control of KMRR, a new method, Reactivity Constraint Method, is applied for time optimal control. This method limits the net reactivity to the amount that can be offset by instantaneous control rod action. The reactivity to be constrained for the constant reactor period should be obtained by the dynamic period equation. A new formulation of the dynamic period equation for 2-point kinetics model is presented. A methematical controller model was applied to the plant simulator, KMRSIM to test this control law. The performance test showed that reactivity constraint approach is also a reliable means for reactor power change control.

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