• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.521-527
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• 2002

This paper presents a dynamic modeling and a robust PID controller design process for the wire bonder head assembly. For the modeling elements, the system is divided into electrical system, magnetic system, and mechanical system. Each system is modeled by using the bond graph method. The PID controller is used for high speed/high accuracy position control of the wire bonder assembly. The Taguchi method is used to evaluate the more robust PID gain combinations than conventional one. This study makes use of an L18 array with three parameters varied on three levels. Computer simulations and experimental results show that the designed PID controller provides more improved signal to noise ratio and reduced sensitivity than the conventional PID controller.

• Journal of the Korean Society of Combustion
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• v.21 no.3
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• pp.16-23
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• 2016

In this study, skeletal mechanisms are produced by directed relation graph with specified threshold value and sensitivity analysis based on species database from the directed relation graph. Skeletal mechanism is optimized through the elimination of unimportant reaction steps by computational singular perturbation importance index. Reduction is performed for the detailed mechanism of methyl butanoate consisting of 264 species and 1219 elementary reactions. Validation shows acceptable agreement for auto-ignition delays in wide parametric ranges of pressure, temperature and equivalence ratio. Methyl butanoate has been proposed as a simple biodiesel surrogate although the alkyl chain consists of four carbon atoms. The resulting surrogate mechanism for n-heptane and MB consists of 76 species and 226 reaction steps including those for NOx.

• Journal of the Semiconductor & Display Technology
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• v.1 no.1
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• pp.21-28
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• 2002

This paper presents a dynamic modeling and a robust PID controller design process for the wire bonder head assembly. For modeling elements, the system is divided into electrical part, magnetic part, and mechanical part. Each part is modeled using the bond graph method. The PID controller is used for high speed/high accuracy position control of the wire bonder assembly. The Taguchi method is used to obtain the more robust PID gain combinations than conventional one. This study makes use of an L18 array with three parameters varied on three levels. Results of simulations and experimental show that the designed PID controller provides a improved ratio of signal to noise and a reduced sensitivity improved to the conventional PID controller.

• Proceedings of the KSME Conference
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• 2001.06b
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• pp.747-753
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• 2001

This paper presents a dynamic modeling and a robust PID controller design process for the wire bonder head assembly. For the modeling elements, the system is divided into electrical system, magnetic system, and mechanical system. Each system is modeled by using the bond graph method. The PID controller is used for high speed/high accuracy position control of the wire bonder assembly. The Taguchi method is used to evaluate the more robust PID gain combinations. This study makes use of an L18 array with three parameters varied on three levels. Computer simulations and experimental results show that the designed PID controller provides more improved signal to noise ratio and reduced sensitivity than the conventional PID controller.

• Journal of the Semiconductor & Display Technology
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• v.9 no.2
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• pp.15-20
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• 2010

This paper deals with minimizing layout area of FPGA design. FPGAs are becoming increasingly important in the design of ASICs since they provide both large scale integration and user-programmability. This paper describes a method to obtain tight bound on the worst-case increase in area when drivers are introduced along many long wires in a layout. The area occupied by minimum-area embedding for a circuit can depend on the aspect ratio of the bounding rectangle of the layout. This paper presents a separator-based area-optimal embeddings for FPGA graphs in rectangles of several aspect ratios which solves the longest path problem in the constraint graph.

• Journal of Acupuncture Research
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• v.30 no.1
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• pp.1-11
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• 2013

Objectives : The 7-zone-diagnostic system is a device for predetermining bodily locations by measuring the energy of the living body. The purpose of this study is to examine correlations between gastroscopy results and zone-5 data from the 7-zone-diagnostic system. Methods : This study was carried out with data from gastroscopy procedures. It involved 115 patients who had been diagnosed with gastritis, esophagitis, or gastric ulcers. These patients were divided into three groups according to the different patterns of zone-5 factors AA, FL2 and FL1. Group A was made up of patients for whom the red bar graph of zone-5 was higher than the normal range for factor AA. Group B was made up of patients for whom the red bar graph of zone-5 was within the normal range for factor AA. Group C was made up of patients for whom the red bar graph of zone-5 was lower than the normal range for factor AA. Group D E and F were made up of same way as group A B and C for factor FL2. Group G H and I were made up of same way as group A B and C for factor FL1. After the collection of gastroscopy results and data on zone-5 from the 7-zone-diagnostic system, the data was analyzed statistically. Results : 1. Group D had a higher ratio of medication than group E, and this result was statistically significant. 2. Group D G had a higher ratio of medication than group E G and group E H, and this result was statistically significant. 3. Group G had a higher ratio of esophagitis than group H, and this result was statistically significant. 4. A Group B H had a higher ratio of esophagitis than group B G, group C G, and group C H, and this result was statistically significant. 5. The medication group had a high score on the function index than the non-medication group, and this result was statistically significant. Conclusions : This study suggests that there is a slight correlation between gastroscopy results and zone-5 data from the 7-zone-diagnostic system. The research resulted in significant data that are helpful for diagnosing digestive system problems through the use of the 7-zone-diagnostic system.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1996.03a
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• pp.132-136
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• 1996

A Study is a experiment which is figure out to aptimum discharge cutting condition of the surfaceroughness, electric discharging speed and electro wear ratio with Ton Toff and V(voltage) as an input condition according to the current(Ip) in an electric spark machine ; 1)Electrode is utilized Cu(coper) and Graphite. 2)Work piece is used the material of carbon steel. The condition of experiment is; 1)Current is varied 0.7(A) to 50(A). 2)Pulse time(Ton) is varied 3($\mu$s) to 240($\mu$s) and also Toff is varied 7($\mu$s) to 20($\mu$s). 3)The time of electric discharging to work piece in each time is 30(min) to 60(min) 4)After the upper side of work piece was measured in radius (5${\mu}{\textrm}{m}$) of syulus analyzed the surface roughness to made the table and graph of Rmax by yielding data. 5)Electro wear ratio is; \circled1Coper was measured cx-machining and post machining but the electronic baiance. \circled2The ex-machining of graphite measured by it, the post-machining was found the data from volume specific gravity and analyzed to made its table and graph on ground the data 6)In order to keep the accuracy of voltage affected to the work piece was equipped with the A.V.R(Automatic Voltage Regulator). 7)The memory scope was sticked to the electric spark machine. 8)In order to preserve the precision of current, to get rid of the noise occured by internal resistance of electric spark machine and to force injecting for the discharge fluid, it made the fixed table for a work piece to minimize the work error by means of one's failure during the electric discharging According to above results, the surface roughness by the variation of electrodw and current was analyzed to compare KS(Korea Standards) It was decided the optimum condition of electric discharge cutting through analyzing the effect of electric discharge speed and electro wear ratio.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.85-90
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• 2000

The fracture toughness and crack propagation behaviors of short nylon66 fiber reinforced Chloroprene rubber nave been Investigated as functions of fiber aspect ratio, fiber content and interphase conditions. The J for crack initiation and rupture were determined for short-fiber reinforced rubber. The values of $J_c$ for most reinforced rubbers were low compared that of matrix. But, $J_r$ at rupture showed a higher value than that of matrix. The crack propagation behaviors were analyzed into 3 patterns with increasing fiber aspect ratio and fiber content. The tearing mechanisms of matrix and fiber reinforced rubber were observed by CCD camera focused on the tip of crack and load-displacement graph. Both cases showed a completely different behaviors

• Proceedings of the Korea Information Processing Society Conference
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• 2020.05a
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• pp.595-598
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• 2020

IoU (Intersection over Union) is the most commonly used index in target detection. The core requirement of target detection is what is in the image and where. Based on these two problems, classification training and positional regression training are needed. However, in the process of position regression, the most commonly used method is to obtain the IoU of the predicted bounding box and ground-truth bounding box. Calculating bounding box regression losses should take into account three important geometric measures, namely the overlap area, the distance, and the aspect ratio. Although GIoU (Generalized Intersection over Union) improves the calculation function of image overlap degree, it still can't represent the distance and aspect ratio of the graph well. As a result of technological progress, Bounding-Box is no longer represented by coordinates x,y,w and h of four positions. Therefore, the IoU can be further optimized with the center point and aspect ratio of Bounding-Box.

• Education of Primary School Mathematics
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• v.11 no.1
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• pp.39-57
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• 2008

The purpose of this study is to affirm what influences the lessons applied by reorganizing the ratio-graph unit of level 6-A on the basis on Realistic Mathematics Education(RME) give on mathematical scholastic achievements and mathematical preferences.In order to achieve the purpose of this study, the experimental study was exerted by making two classes of 6 grades in J elementary school located in Gumi city, Gyeongbuk province as subjects. In this study, test of degree of the mathematics learning ability of student, multiple-choice test and descriptive test of the learning dispositions of student were exerted and the results were t-test officially. The results and the conclusions of this study were as follows: First, the results acquired by officially t-test the levels of the mathematics learning ability of student of the group taught by lessons according to the teaching materials reorganized on the basis of RME and the group taught by lessons according to the 7th curriculum show a meaningful difference(p=.007). This means that the lessons according to the teaching materials reorganized on the basis of RME showed meaningful influences on the improvement of degree of the mathematics learning ability of student. Second, the results acquired by officially t-test the learning dispositions of student multiple-choice test of the group taught by lessons according to the teaching materials reorganized on the basis of RME and the group taught by lessons according to the 7th curriculum show a meaningful difference. Especially in the factors of 'mathematical will'(p=.017) and 'mathematical value'(p=.029) were meaningful differences. Also in the descriptive test of the learning dispositions of student, the experimental class showed that it had the potential possibility to have more positive attitudes meaningfully in comparison with the compared class. This means that the lessons according to the teaching materials reorganized on the basis of RME showed meaningful influences on the learning dispositions of student.