• Title/Summary/Keyword: Mounting Time

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An Experimental Study on Wafer Demounting by Water Jet in a Waxless Silicon Wafer Mounting System

  • Kim, Kyoung-Jin;Kwak, Ho-Sang;Park, Kyoung-Seok
    • Journal of the Semiconductor & Display Technology
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    • v.8 no.2
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    • pp.31-35
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    • 2009
  • In the silicon wafer polishing process, the mounting stage of silicon wafer on the ceramic carrier block has been using the polishing template which utilizes the porous surface instead of traditional wax mounting method. Here in this article, the experimental study is carried out in order to study the wafer demounting by water jet and the effects of operating conditions such as the water jet flowrate and the number of water jet nozzles on the wafer demounting time. It is found that the measured wafer demounting time is inversely proportional to the water flowrate per nozzle, regardless of number of nozzles used; implying that the stagnation pressure by the water jet impingement is the dominant key factor. Additionally, by using the transparent disk instead of wafer, the air bubble formation and growth is observed under the disk, making the passage of water flow, and subsequently demounting the wafer from the porous pad.

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Development of the Process Planning Program for a Multi-functional Surface Mounting Device (다기능 표면실장기의 공정계획 프로그램 개발)

  • Sohn, Jin-Hyeon;Yu, Sung-Yeol;Kang, Jang-Ha;Park, Sung-Soo;Oh, Byung-Jun;Seong, Pil-Young
    • IE interfaces
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    • v.10 no.1
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    • pp.155-167
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    • 1997
  • The purpose of this study is to develop the program for efficient operation of a multi-functional surface mounting device(SMD) which mount various components on a printed circuit board(PCB). These components are provided by diverse types of feeders such as cassette, stick and tray feeders. The SMD has one or two heads. In the SMD, the positions of PCB and feeders and fixed, and the head moves to pick up a component from a feeder and to mount it on the PCB. The number of lanes occupied by each feeder and the nozzle used for each component can be different. We develop an off-line program to minimize the cycle-time of the SMD by studying the optimal assignment of feeders and the optimal mounting sequence of components. Graphical User Interface(GUI) is also developed. Additionally, we consider the line balancing problem which appears when two SMDs are used sequentially.

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Comparative Study of Commercial Characters of Cocoon Produced by Ripe and Unripe Bivoltine Larvae (Bombyx mori L.) Mounted at Different Maturation Levels

  • Rahmathulla, V.K.;Haque, S.Z.;Geetha Devi, R.G.
    • International Journal of Industrial Entomology and Biomaterials
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    • v.7 no.1
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    • pp.79-82
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    • 2003
  • To study the effect of mounting fully ripe and unripe silkworms at different maturation percentage, the ripe and unripe silkworms were mounted separately and observed the cocoon and reeling characters. The significant difference in the cocoon and reeling parameters was observed between all ripe and unripe batches except for summer season. The silkworms collecting together and mounting at a time can be recommended only in summer season and at certain level during rainy season.

Design of a NAND Flash Memory File System to Improve System Boot Time

  • Park, Song-Hwa;Lee, Tae-Hoon;Chung, Ki-Dong
    • Journal of Information Processing Systems
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    • v.2 no.3 s.4
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    • pp.147-152
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    • 2006
  • NAND flash memory-based embedded systems are becoming increasingly common. These embedded systems have to provide a fast boot time. In this paper, we have designed and proposed a flash file system for embedded systems that require fast booting. By using a Flash Image Area, which keeps the latest flash memory information such as types and status of all blocks, the file system mounting time can be reduced significantly. We have shown by experiments that our file system outperforms YAFFS and RFFS.

A Study on The Real-Time Processing of The Position Matching and Inspection Algorithm in SMT (SMT에서 정합 및 부품검사 알고리즘의 실시간 처리에 관한 연구)

  • 차국찬;박일수;최종수
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.29B no.1
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    • pp.76-84
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    • 1992
  • The vision system is essential for SMT(Surface Mounting Technology) automation. The system plays the role of matching the positions betweem SMD and PCB, and inspecting SMD in the final stage of mounting. Real-time processing and high-precision are indispensable for practical purpose. In this paper, a new algorithm for position matching and inspection of SMD is proposed, and which is implemented on the DSP board using DSP board using DSP5600. Experimental results show mean matching error within 0.1 mm in the direction of x,y and execution time within 300msec. Therefore, we could attain high-speed and high-precision of the vision system for SMT automation.

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Relationship between Various Estrous Behavioral Signs and Ovulation Time in Dairy Cows (젖소의 다양한 발정 행동 징후와 배란 시간과의 관계)

  • Son, J.K.;Park, S.B.;Park, S.J.;Baek, K.S.;Ahn, B.S.;Kim, H.S.;Hwang, S.J.;Ju, J.C.;Park, C.K.
    • Journal of Embryo Transfer
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    • v.22 no.1
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    • pp.9-13
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    • 2007
  • The objective of this study was to investigate the relationship between various estrous behavior and ovulation time, and to determine which estrous behavior could predict ovulation time more accurately. In total, 37 ovulations and 28 estrous detection were observed in 51 Holstein-Friesian dairy cows. Various estrous behavior were observed during 72 h from two days after $PGF_2{\alpha}$ injection and their relation with the time of ovulation (ultrasound examinations at 4-h intervals) was investigated. In estrous periods, the rate of sniffing, chin resting, mounting, standing heat was 81%, 78%, 78% and 56%, respectively. Ovulation occurred $25.6{\pm}7.9h$ after onset of estrus (ranging between 7 and 37h) and $13.4{\pm}7.1h$ after end of estrus (ranging between 1 and 28h). Interval between onset of estrus and ovulation time was significantly (p<0.05) shorter for standing heat $(17.33{\pm}5.83h)$ than for mounting, sniffing and chin resting $(23.58{\pm}5.12h,\;24.25{\pm}6.09h,\;23.42{\pm}6.04h)$. In 88% of the animals that displayed mounting, ovulation occurred between $16{\sim}28h$ after onset of mounting. Onset of standing heat, sniffing and chin resting occurred between $10{\sim}22(81%)h,\;16{\sim}28(79%)h\;and\; 19{\sim}31(79%)h$ before ovulation respectively. Sniffing and chin resting were displayed during the non-estrous period and are therefore, not useful predictors of ovulation time. The standing heat and mounting can be a good predictor for time of ovulation but the disadvantage of using standing heat is that only a limited number of cows display standing heat. Thus, it is concluded that mounting behavior could be the best predictor for time of ovulation.

Mounting Time Reduction and Clean Policy using Content-Based Block Management for NAND Flash File System (NAND 플래시 파일 시스템을 위한 내용기반 블록관리기법을 이용한 마운트 시간 감소와 지움 정책)

  • Cho, Wan-Hee;Lee, Dong-Hwan;Kim, Deok-Hwan
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.46 no.3
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    • pp.41-50
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    • 2009
  • The flash memory has many advantages such as low power consumption, strong shock resistance, fast I/O and non-volatility. And it is increasingly used in the mobile storage device. Many researchers are studying the YAFFS, NAND flash file system, which is widely used in the embedded device. However, the existing YAFFS has two problems. First, it takes long time to mount the YAFFS file system because it scans whole spare areas in all pages. Second, the cleaning policy of the YAFFS does not consider the wear-leveling so that it cannot guarantee the duration of data completely. In order to solve these problems, this paper proposes a new content-based YAFFS that consists of a mounting time reduction technique and a content-cleaning policy by using content-based block management. The proposed method only scans partial spare areas of some special pages and provides the block swapping which enables the wear-leveling of data blocks. We performed experiments to compare the performance of the proposed method with those of the JFFS2 system and YAFFS system. Experimental results show that the proposed method reduces the average mounting time by 82.2% comparing with JFFS2 and 42.9% comparing with YAFFS. Besides, it increases the life time of the flash memory by 35% comparing with the existing YAFFS whereas no overheat is added.

Real-Time Cattle Action Recognition for Estrus Detection

  • Heo, Eui-Ju;Ahn, Sung-Jin;Choi, Kang-Sun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.4
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    • pp.2148-2161
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    • 2019
  • In this paper, we present a real-time cattle action recognition algorithm to detect the estrus phase of cattle from a live video stream. In order to classify cattle movement, specifically, to detect the mounting action, the most observable sign of the estrus phase, a simple yet effective feature description exploiting motion history images (MHI) is designed. By learning the proposed features using the support vector machine framework, various representative cattle actions, such as mounting, walking, tail wagging, and foot stamping, can be recognized robustly in complex scenes. Thanks to low complexity of the proposed action recognition algorithm, multiple cattle in three enclosures can be monitored simultaneously using a single fisheye camera. Through extensive experiments with real video streams, we confirmed that the proposed algorithm outperforms a conventional human action recognition algorithm by 18% in terms of recognition accuracy even with much smaller dimensional feature description.

Implementation of Efficient and Reliable Flash File System (효율적이고 신뢰성 있는 플래시 파일시스템의 구현)

  • Jin, Jong-Won;Lee, Tae-Hoon;Lee, Seung-Hwan;Chung, Ki-Dong
    • Journal of Korea Multimedia Society
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    • v.11 no.5
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    • pp.651-660
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    • 2008
  • Flash memory is widely used in embedded systems because of its benefits such as non-volatile, shock resistant, and low power consumption. However, NAND flash memory suffers from out-place-update, limited erase cycles, and page based read/write operations. To solve these problems, YAFFS and RFFS, the flash memory file systems, are proposed. However YAFFS takes long time to mount the file system, because all the files are scattered all around flash memory. Thus YAFFS needs to fully scan the flash memory. To provide fast mounting, RFFS has been proposed. It stores all the block information, the addresses of block information and meta data to use them at mounting time. However additional operations for the meta data management are decreasing the performance of the system. This paper presents a new NAND flash file system called ERFFS (Efficient and Reliable Flash File System) which provides fast mounting and recovery with minimum mata data management. Based on the experimental results, ERFFS reduces the flash mount/recovery time and the file system overhead.

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Ultrasonic ACF Bonding Technique for Mounting LCD Driver ICs (LCD 구동 IC의 실장을 위한 초음파 ACF접합 기술)

  • Joung, Sang-Won;Yun, Won-Soo;Kim, Kyung-Soo
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.6
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    • pp.543-547
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    • 2008
  • In the paper, we develop the ultrasonic bonding technique for LCD driver chips having small size and high pin-density. In general, the mounting technology for LCD driver ICs is a thermo-compression method utilizing the ACF (An-isotropic Conductive Film). The major drawback of the conventional approach is the long process time. It will be shown that the conventional ACF method based on thermo-compression can be remarkably enhanced by employing the ultrasonic bonding technique in terms of bonding time. The proposed approach is to apply the ultrasonic energy together with the thermo-compression methodology for the ACF bonding process. To this end, we design a bonding head that enables pre-heating, pressure and ultrasonic excitation. Through the bonding experiments mainly with LCD driver ICs, we present the procedures to select the best combination of process parameters with analysis. We investigate the effects of bonding pressure, bonding time, pre-heating temperature before bonding, and the power level of ultrasonic energy. The addition of ultrasonic excitation to the thermo-compression method reduces the pre-heating temperature and the bonding process time while keeping the quality bonding between the LCD pad and the driver IC. The proposed concept will be verified and demonstrated with experimental results.