• Journal of Korea Foundry Society
• /
• v.32 no.6
• /
• pp.284-288
• /
• 2012

The effects of Si content on the variation of microstructure and processing window of austempered ductile cast iron were investigated. Four different Si contents between 2.42 and 3.37 wt.% were used. The influence of silicon on the microstructure and processing window of these materials were studied. Austenitizing was performed at $900^{\circ}C$ for 60min and austempering temperature were both $340^{\circ}C$ and $360^{\circ}C$ and austempering time were for 4min upto 119min and for 5min upto 160min respectively. After heat treatment, the evolution of stage I and stage II were performed by optical metallography, XRD, hardness test. The results showed that $t_2$ was delayed as Si contents was increased due to the fact that Si retarded the formation of cementite ($Fe_3C$). The high silicon content promoted the stability of the metastable two-phase combination of austenite and ausferrite.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2007.10a
• /
• pp.351-354
• /
• 2007

In recent years, digital processing techniques have been applied diversity of fields. Typical signal processing techniques are speech processing and image processing. And filters for the signal processing can be divided in FIR (finite impulse response) filter and IIR (infinite impulse response) filter. Compared with IIR filter, the FIR Filter has a defect of high-degree, but has a merit of stability and uses simply. Futhermore, FIR filter also has linear phase response characteristics, it is using in fields regarding wave information importantly. To FIR Filter design, the main issue is to remove the Gibbs phenomenon. Therefore, in this paper I was proposed a method using FIR digital filter applied a modified window function and the method was compared with conventional methods.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 1998.11a
• /
• pp.194-197
• /
• 1998

Image Processing은 Image Data가 대량이고 내재된 정보가 병렬로 연관성을 가진다는 측면에서 실시간 처리가 용이하지 알다. 본 연구에서는 High Speed Real Time Image Processing을 위한 IPU(Image Processing Unit)와 이를 구동하기 위한 High Speed Real Time image Processing Language인 IPASM(Image Processing Assembly)을 제안한다. 우선 IPU의 기본개념을 설명하고 IPU의 구현을 위한 IPLU(Image Processing Logic Unit)를 설계한다. 그 후 Window98환경에서 구동 가능한 IPASM Interpreter를 실제로 제작하여 IPU의 동작방식을 간접적으로 진단한다.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2000.10a
• /
• pp.161-164
• /
• 2000

A cyclic shop is a production system that repeatedly produces identical sets of jobs, called minimal part sets, in the same loading and processing sequence. We consider a version of cyclic shop where the operations are processed and unloaded within time limits, so called a time window. We model the shop using an event graph model, a class of Petri nets. To represent the time window constraint, we introduce places with negative time delays. From the shop modeling graph, we develop a linear system model based on the max- plus algebra and characterize the conditions on the existence of a stable schedule.

• Proceedings of the IEEK Conference
• /
• 2000.07b
• /
• pp.889-893
• /
• 2000

In this paper, a method to detect lanes and obstacles from the images captured by a CCD camera fitted in an automobile is proposed, and a new terminology “Moving Window” is defined. Processing the input dynamic images in real time can cause quite a few constraints in terms of hardware. In order to overcome these problems and detect lanes and obstacles in real time using the images, the optimal size of “Moving Window” is determined, based upon road conditions and automobile states. The real time detection is made possible through the technique. For each image frame, the moving window is moved in a predicted direction, the accuracy of which is improved by the Kalman filter estimation. The feasibility of the proposed algorithm is demonstrated through the simulated experiments of freeway driving.

• The KIPS Transactions:PartA
• /
• v.10A no.5
• /
• pp.479-486
• /
• 2003

As the Internet appliances like digital TV, Internet set-top boxes, and Internet phone, are showing up in the market, the economics of real-time operating system (RTOS), which is an essential for controlling those devices, is expanding faster than ever before. ETRI has developed describes RTOS called Qplus-P, targeting various platforms ranging from PDA to Internet set-top box and home server. This paper describes the implementation of graphic window library for Qplus-P. The Qplus-P graphic window library was implemented using tiny-X graphic server and gtk graphic toolkit, which are open source software. To port this library to various aliances, hangul processing, screen rotation, touch screen, and graphic acceleration functions are added to the tiny-X graphic server of the implementd graphic window library. Currently, Qplus-P graphic window is running on ARM-based appliances such as iPaq PDA, Samsung S3C2400 board, Zaurus PDA, and on Home Server that uses x86 processor. Qplus-P graphic library is provided as a of Qplus-P target builder.

• Journal of Institute of Control, Robotics and Systems
• /
• v.16 no.11
• /
• pp.1089-1095
• /
• 2010

We propose an image segmentation method for auto-teaching system of PCB (Printed Circuit Board) assembly inspection machines. The inspection machine acquires images of all components in PCB, and then compares each image with its standard image to find the assembly errors such as misalignment, inverse polarity, and tombstone. The component window that is the area of component to be acquired by camera, is one of the teaching data for operating the inspection machines. To reduce the teaching time of the machine, we newly develop the image processing method to extract the component window automatically from the image of PCB. The proposed method segments the component window by excluding the soldering parts as well as board background. We binarize the input image by use of HSI color model because it is difficult to discriminate the RGB colors between components and backgrounds. The linear combination of the binarized images then enhances the component window from the background. By use of the horizontal and vertical projection of histogram, we finally obtain the component widow. The experimental results are presented to verify the usefulness of the proposed method.

• The KIPS Transactions:PartC
• /
• v.9C no.5
• /
• pp.743-748
• /
• 2002

In recent research for the Internet, many studies have investigated the Diffserv AS architecture that can provide Quality of Service. However, this architecture still lacks the qualification to provide full use of the bandwidth to the customer In this paper, we propose the TS2W3C (Time Sliding Two Window Three Color) marking algorithm to improve the fair share of bandwidth by enhancing the TSW (Time Sliding Window) marking algorithm. Our proposed mechanism provides the bandwidth relatively more fairly than the TSW mechanism.

• Smart Structures and Systems
• /
• v.14 no.4
• /
• pp.719-741
• /
• 2014

Monitoring surface cracks is important to ensure the health of concrete structures. However, traditional visual inspection to monitor the concrete cracks has disadvantages such as subjective inspection nature, associated time and cost, and possible danger to inspectors. To alter the visual inspection, a complete procedure for automated crack assessment based on adaptive digital image processing has been proposed in this study. Crack objects are extracted from the images using the subtraction with median filter and the local binarization using the Niblack's method. To adaptively. determine the optimal window sizes for the median filter and the Niblack's method without distortion of crack object an optimal filter size index (OFSI) is proposed. From the extracted crack objects using the optimal size of window, the crack objects are decomposed to the crack skeletons and edges, and the crack width is calculated using 4-connected normal line according to the orientation of the local skeleton line. For an image, a crack width nephogram is obtained to have an intuitive view of the crack distribution. The proposed procedure is verified from a test on a concrete reaction wall with various types of cracks. From the crack images with different crack widths and patterns, the widths of cracks in the order of submillimeters are calculated with high accuracy.

• Journal of Digital Contents Society
• /
• v.13 no.1
• /
• pp.21-29
• /
• 2012

In ubiquitous computing environment, rising large scale data exchange through sensor network with sharply growing the internet, the processing of the continuous stream data is required. Therefore there are some mining researches related to the extracting of frequent structures and the efficient query processing of XML stream data. In this paper, we propose a mining method to extract frequent structures of XML stream data in recent window based on the active window sliding using trigger rule. The proposed method is a basic research to control the stream data flow for data mining and continuous query by trigger rules.