• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.26-31
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• 2002

The recent machine tools are requested so high-quality processing and productivity increasing. Therefore, it is so necessary to develop technology fur high-speed and high-precision. This thesis touches on the development of high speed and intellectual line center. At first, the line center is necessary that strong structure, compact structure and light weight design for high-speed processing and transfer. So, it is necessary that examination of new materials and structures for light-weight and control devices for precision processing. So. it is going to make mention of the process of 1st model production for the above-mentioned based on test model production and evaluation.

• Transactions of Materials Processing
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• v.27 no.1
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• pp.12-17
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• 2018

This paper outlines the research findings on the microstructure and mechanical properties of AZ31 Mg alloy fabricated by differential speed rolling (DSR) with respect to processing variables such as temperature, roll speed ratio (RSR), and deformation route. The resultant microstructure of the sample, deformed by 2-pass DSRs at 473 K, comprised finer grains with more uniform distribution than those at 573 and 623 K. This was due to active recrystallization, which was expected to appear during DSR at temperatures higher than 573 K. When the sample was deformed via DSR with RSR of 1:4 for the upper and lower rolls at 453 K, the values of yield and ultimate tensile strength were observed to be higher than their counterpart with RSR of 1:1. The application of sample rotation around the longitudinal axis would give rise to an excellent combination of tension strength (~330 MPa) and ductility (~20 %) at ambient temperatures. This is discussed based on its uniform fine grained structure and the softening of basal texture.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.5 no.3
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• pp.65-70
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• 2006

The AWJM(Abrasive Water-jet Machining) technology is one of the cutting technologies, which can cut various materials with 2 or 3 times of the speed of sound. In this study, processing conditions such as jet-pressure, cutting speed, orifice diameter and stand-off distance, are used by following the design of experiments with 3 levels. Al6061 material which is normally applied on the field, is applied. Through the S/N ratio analysis with measured values, the optimization value of processing conditions to minimize the surface roughness and taper value is obtained. The order of significance is as follows; jet pressure, cutting speed, abrasive mixing ratio, orifice diameter and stand-off distance. RSM(Response Surface Method) is applied to find the optimal processing conditions to minimize both the surface roughness and the taper value by using jet pressure, cutting speed and abrasive mixing ratio.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38B no.7
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• pp.519-525
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• 2013

The traffic classification is a preliminary and essential step for stable network service provision and efficient network resource management. However, the payload signature-based method has a significant drawback in high-speed network environment that the processing speed is much slower than other method such as header-based and statistical methods. In this paper, We propose the server IP, Port cache-based traffic classification method using application traffic locality to improve the processing speed of traffic classification. The suggested method achieved about 10 folds improvement in processing speed and 10% improvement in completeness over the payload-based classification system.

• Journal of Digital Convergence
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• v.12 no.11
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• pp.379-386
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• 2014

In this paper, the processing speed of Grabcut algorithm in order to efficiently improve the GPU (Graphics Processing Unit) for processing the data from the method. Grabcut algorithm has excellent performance object detection algorithm. Grabcut existing algorithms to split the foreground area and the background area, and then background and foreground K-cluster is assigned a cluster. And assigned to gradually improve the results, until the process is repeated. But Drawback of Grabcut algorithm is the time consumption caused by the repetition of clustering. Thus GPGPU (General-Purpose computing on Graphics Processing Unit) using the repeated operations in parallel by processing Grabcut algorithm to effectively improve the processing speed of the method. We proposed method of execution time of the algorithm reduced the average of about 95.58%.

• Journal of Information Processing Systems
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• v.6 no.3
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• pp.403-412
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• 2010

Multi-Relay Networks should accommodate mobile users of various speeds. The cellular system should meet the minimum residency time requirements for handover calls while considering an efficient use of available channels. In this paper, we design speed-sensitive handover under dynamic hierarchical cellular systems, in which mobile users are classified according to the mean speed of mobile users and each class has its cellular layer. In order to meet the minimum residency time, the cell size of each cellular layer is dynamically determined depending on the distributions of mean speeds of mobile users. Since the speed-dependent non-preferred cell can provide a secondary resource, overflow and take-back schemes are adopted in the system. We develop analytical models to study the performance of the proposed system, and show that the optimal cell size improves the blocking probability.

• The Journal of Information Technology
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• v.4 no.3
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• pp.155-163
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• 2001

In this paper, we implemented sigmoid active function which make it difficult to design of the digital neuron networks. Therefore, we designed of the high speed processing of the sigmoid function in order to digital neural networks. we designed of the MAC(Multiplier and Accumulator) operation unit used residue number system without carry propagation for the high speed operation. we designed of MAC operation unit and sigmoid processing unit are proved that it could run of the high speed. On the simulation, the faster than 4.6ns on the each order, we expected that it adapted to the implementation of the high speed digital neural network.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.2
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• pp.8-18
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• 1993

A multi-font, multi-size and high speed character recognition system is designed. The design principles are simpilcity of algorithm, adaptibility, learnability, hierachical data processing and attention by feed back. For the multi-size character recognition, the extracted character images are normalized. A hierachical classifier classifies the feature vectors. Feature is extracted by applying the directional receptive field after the directional dege filter processing. The hierachical classifier is consist of two pre-classifiers and one decision making classifier. The effect of two pre-classifiers is prediction to the final decision making classifier. With the pre-classifiers, the time to compute the distance of the final classifier is reduced. Recognition rate is 95% for the three documents printed in three kinds of fonts, total 1,700 characters. For high speed implemention, a multiprocessor system with the ring structure of four transputers is implemented, and the recognition speed of 30 characters per second is aquired.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.149-149
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• 2000

We experimented on AGV driving test with color CCD camera which is setup on it. This paper can be divided into two parts. One is image processing part to measure the condition of the guideline and AGV. The other is part that obtains the reference steering angle through using the image processing parts. First, 2 dimension image information derived from vision sensor is interpreted to the 3 dimension information by the angle and position of the CCD camera. Through these processes, AGV knows the driving conditions of AGV. After then using of those information, AGV calculates the reference steering angle changed by the speed of AGV. In the case of low speed, it focuses on the left/right error values of the guide line. As increasing of the speed of AGV, it focuses on the slop of guide line. Lastly, we are to model the above descriptions as the type of PID controller and regulate the coefficient value of it the speed of AGV.

• Laser Solutions
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• v.9 no.2
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• pp.11-15
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• 2006

We report experimental results on the high-speed micromachining using a femtosecond laser (800 nm, 130 fs, 1kHz) and galvanometer scanner system (Raylase, Germany). Periodic hole drilling of silicon and glass with the scan speed of 1-20 mm/s is demonstrated. Finally, we demonstrate the utility of the femtosecond laser application to ITO patterning by using a high-speed femtosecond laser scanner system.