• 제어로봇시스템학회:학술대회논문집
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• 1993.10b
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• pp.30-35
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• 1993

Simple recurrence relations for calculating completion times of various storage polices (unlimited, intermediate storages(FIS), finite intermediate storages(FIS), no intermediate storage(NIS), zero wait(ZW) for serial multi-product multi-unit processes are suggested. Not only processing times but also transfer times, set-up (clean-up) times of units and set-up times of storages are considered. Optimal scheduling strategies with zero transfer times and zero set-up times had been developed as a mixed integer linear programniing(MILP) formulation for several intermediate storage policies. In this paper those with non-zero transfer times, non-zero set-up times of units and set-up times of storages are newly proposed as a mixed integer nonlinear programming(MINLP) formulation for various storage polices (UIS, NIS, FIS, and ZW). Several examples are tested to evaluate the robustness of this strategy and reasonable computation times.

• The korean journal of orthodontics
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• v.35 no.6 s.113
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• pp.459-474
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• 2005

Making a precise and ideal set-up model is an essential part in the indirect bonding procedure for lingual orthodontic treatment. To evaluate the accuracy of the making a set-up model, 22 adult patients who received lingual orthodontic treatment with 4 bicuspid extractions were selected, and 3 sets of dental models (before, set-up, and after treatment) were measured using the set-up model gauge, an instrument for measuring the inclination and angulation of the clinical crowns on the dental model. Two sets of lateral cephalograms (before and after) from each patient were also evaluated. The mean difference between the before treatment model and the set-up model was $-3.93{\pm}6.98^{\circ}$ for the inclination and $1.87{\pm}5.79^{\circ}$ for the angulation. And the mean difference between the set-up model and the after treatment model was $-4.31{\pm}5.91^{\circ}$ labiolingually and $-2.16{\pm}3.27^{\circ}$ mesiodistally, The after treatment model differed from the before treatment model about $-8.24{\pm}5.39^{\circ}$ in inclination. There were no significant difference between the measured gauge that measured from the dental model using the set-up model gauge and the calculated gauge angle measured from the lateral cephalogram using constructed points and lines. Using the set-up model gauge, it is possible to evaluate the study model 3-dimensionally in relation with the patient's lateral cephalogram and establish whether the doctor's prescription or overcorrection is built in the set-up model precisely.

• Journal of Korean Institute of Industrial Engineers
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• v.25 no.1
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• pp.141-149
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• 1999

In this paper, we consider multiple-class queueing systems in which the server starts a set-up as soon as the number of customers in the "start-up class" reaches threshold N. After the set-up the server starts his service. We obtain the Laplace-Stieltjes transform and the mean of the waiting times of each class of customers for FCFS and non-preemptive priority disciplines.

• Journal of the Korean Operations Research and Management Science Society
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• v.17 no.1
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• pp.43-54
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• 1992

This paper discusses a real time production control system of a FMS (Flexible Manufacturing System). The control is organized in a hierarchical structure according to the various decisions at the different time scales. In the earlier work-set-up time was not considered. Because the capacity of the toll magazine is limited, this assumption may not be adequate for selecting times to change configurations so that new part family can be produced. The goal of the control system is to meet production requirements while the machines fail and are repaired at random times. In this thesis the machien failure and set-up are considered simultaneously. Here the hedging point of this system is calculated, and the formulation of the dynamic control for FMS that has unreliable machines with set-up suggested.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1323-1326
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• 2003

In this paper, we propose set-up model of silicon steel cold rolling mill. Until now, the working of Silicon Steel is operated using the look-up table value of roll force which a field operator finds by making good use of his experience. Therefore, the standardization of data and an improvement of the quality on product are very difficult. So we establish neural model using field data of various kinds of coil at each pass.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.5
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• pp.109-115
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• 2008

As structures are getting super-rise and large-sized, introducing the construction methods such as prefabrication of bar-meshes and complex method are being actively discussed to pursue the high quality of reinforced concrete, the simplification of field works, and the reduction of duration, as well as the study on how to connect reinforcing rods, which occurs while applying the same methods, is in progress Also, the pressure welded joint is a kind of method that heats the ends of reinforced bars locally and joint them, and after the pressure welding, the vulnerable part in the reinforced bar occur. Thus, in the construction field, the throughout quality control is necessary because of the delayed duration and the lowered construct ability. In this study, of the traditional lap splice method and the mechanical splice one, the screw coupler, we tried to look into through experiments the prefabrication method of bar-meshes, a typical joint method usually used for the joint parts for PSC structures applying the reinforced bar with its big diameter, and a newly-developed up-set coupler method. And we also examined the characteristic of tensile.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.3
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• pp.498-503
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• 2005

As important device that decide output load in superannuated thermoelectric power plant which do Turbine Load Set Motor device. This generation of electric power system operated Set Up Range Motor according to Set Up value that operator manufactures by hand circumvolve, and generation of electric power output load derision is consisted by internal action including Motor Therefore, in this research passively output load operated Turbine Motor Drive equipment that can have existing Turbine Load Set Motor Performance developing Digital Drive Unit device design. Also control algorithm implementation and existing Turbine Load Set Motor Drive and connection possibility through designed controlling system to connect basis function that decide development output load with Digital Drive Unit that designed also with existing Motor Drive Unit and can be operated.

• Radiation Oncology Journal
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• v.36 no.1
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• pp.54-62
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• 2018

Purpose: To investigate set-up errors, suggest the adequate planning target volume (PTV) margin and image-guided radiotherapy frequency in head and neck (H&N) cancer treated with intensity-modulated radiotherapy (IMRT) assessed by kV cone-beam computed tomography (CBCT). Methods: We analyzed 360 CBCTs in 60 patients with H&N cancer treated with IMRT. The target delineation was contoured according to ICRU62. PTVs were generated by adding a 3-5 mm margin in all directions to the respective clinical target volumes. The kV CBCT images were obtained at first three days of irradiation and weekly thereafter. The overall mean displacement, range, systematic (${\Sigma}$) and random (${\sigma}$) errors were calculated. Adequate PTV margins were calculated according to the van Herk formula ($2.5{\Sigma}+0.7r$). Results: The mean of set-up errors was less than 2 mm in any direction. The overall frequency of set-up displacements greater than 3 mm was 3.9% in medial-lateral (ML) direction, 8% in superior-inferior (SI) direction, and 15.5% in anterior-posterior (AP) direction. The range of translations shifts was 0-9 mm in ML direction, 0-5 mm in SI direction and 0-10 mm in AP direction, respectively. After systematic set-up errors correction, the adequate margin to overcome the problem of set-up errors was found to be less than 3 mm. Conclusion: Image-guided kV CBCT was effective for the evaluation of set-up accuracy in H&N cancer. The kV CBCT at first three fractions and followed-by weekly appears adequate for reducing significantly set-up errors in H&N cancer treated with IMRT technique. Finally, 3-5 mm PTV margins appear adequate and safe to overcome the problem of set-up errors.

• The Journal of Korean Society for Radiation Therapy
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• v.32
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• pp.7-15
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• 2020

Purpose: In modern radiotherapy technology, several methods of image guided radiation therapy (IGRT) are used to deliver accurate doses to tumor target locations and normal organs, including CBCT (Cone Beam Computed Tomography) and other devices, ExacTrac System, other than CBCT equipped with linear accelerators. In previous studies comparing the two systems, positional errors were analysed rearwards using Offline-view or evaluated only with a Yaw rotation with the X, Y, and Z axes. In this study, when using CBCT and ExacTrac to perform 6 Degree of the Freedom(DoF) Online IGRT in a treatment center with two equipment, the difference between the set-up calibration values seen in each system, the time taken for patient set-up, and the radiation usefulness of the imaging device is evaluated. Materials and Methods: In order to evaluate the difference between mobile calibrations and exposure radiation dose, the glass dosimetry and Rando Phantom were used for 11 cancer patients with head circumference from March to October 2017 in order to assess the difference between mobile calibrations and the time taken from Set-up to shortly before IGRT. CBCT and ExacTrac System were used for IGRT of all patients. An average of 10 CBCT and ExacTrac images were obtained per patient during the total treatment period, and the difference in 6D Online Automation values between the two systems was calculated within the ROI setting. In this case, the area of interest designation in the image obtained from CBCT was fixed to the same anatomical structure as the image obtained through ExacTrac. The difference in positional values for the six axes (SI, AP, LR; Rotation group: Pitch, Roll, Rtn) between the two systems, the total time taken from patient set-up to just before IGRT, and exposure dose were measured and compared respectively with the RandoPhantom. Results: the set-up error in the phantom and patient was less than 1mm in the translation group and less than 1.5° in the rotation group, and the RMS values of all axes except the Rtn value were less than 1mm and 1°. The time taken to correct the set-up error in each system was an average of 256±47.6sec for IGRT using CBCT and 84±3.5sec for ExacTrac, respectively. Radiation exposure dose by IGRT per treatment was measured at 37 times higher than ExacTrac in CBCT and ExacTrac at 2.468mGy and 0.066mGy at Oral Mucosa among the 7 measurement locations in the head and neck area. Conclusion: Through 6D online automatic positioning between the CBCT and ExacTrac systems, the set-up error was found to be less than 1mm, 1.02°, including the patient's movement (random error), as well as the systematic error of the two systems. This error range is considered to be reasonable when considering that the PTV Margin is 3mm during the head and neck IMRT treatment in the present study. However, considering the changes in target and risk organs due to changes in patient weight during the treatment period, it is considered to be appropriately used in combination with CBCT.

• The Journal of the Korea Contents Association
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• v.7 no.4
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• pp.133-140
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• 2007

The current 3D CG animation pipe line, which is the production system, does not have an effective solution that all animation departments are able to start their jobs independently against other animation departments. It is generally acknowledged that we could not do animating task before the modeling and set-up task. This kind of process has caused loss of labour. We could expect lasting problems which is stopping marking animating process before the previous process done again in case of requiring editing the jobs which are modeling and set-up. We could solve these "bottleneck" situation with "master character" defined as standard, so that animate and retake the job independently against other departments. These new process could accelerate the animation pipe line system.