• Title/Summary/Keyword: Mounting block

Search Result 25, Processing Time 0.026 seconds

Design of a DC-DC Converter for Portable Device (휴대기기용 DC-DC 부스트 컨버터 집적회로설계)

  • Lee, Ja-kyeong;Song, Han-Jung
    • Journal of Korea Society of Industrial Information Systems
    • /
    • v.22 no.2
    • /
    • pp.71-78
    • /
    • 2017
  • In This Paper, A DC-DC Boost Converter for Portable Device has been Proposed. The Converter Which is Operated with 1 MHz High Switching Frequency is Capable of Reducing Mounting Area of Passive Devices Such as Inductor and Capacitor, Consequently is Suitable for Portable Device. This Boost Converter Consists of a Power Stage and a Control Block and a Protect Block. Proposed DC-DC Boost Converter has been Designed a 0.18 um Magnachip CMOS Process Technology, we Examined Performances of the Fabricated Chip and Compared its Measured Results with SPICE Simulation Data. Simulation Results Show that the Output Voltage is 4.8 V in 3.3 V Input Voltage, Output Current 95 mA Which is Larger than 20~50 mA.

Development of a Test Strip Reader for a Lateral Flow Membrane-based Immunochromatographic Assay

  • Park, Je-Kyun;Kim, Suhyeon
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • v.9 no.2
    • /
    • pp.127-131
    • /
    • 2004
  • A low-cost, simple strip reader system using a linear movement mechanism of CD-ROM deck has been developed to characterize a lateral flow membrane-based immunochromatographic assay. The test strip reader was assembled by a CD-ROM deck and home-made optical head especially designed for immunoassays. The optical head for detecting reflected light from the test strip surface consists of green light-emitting diode, large area silicon photodiode, and anodized aluminum mounting block providing a slit structure for cutting light from the LED. The stepping motor of the deck was operated in the full step mode, whose distance of each reading point is about 0.15mm. The performance of the strip reader was tested by analysis of HBV(hepatitis B virus) antigen test kit. This strip reader can be useful for inexpensive, disposable, and membrane-based assays that provide visual evidence of the presence of an analyte in a liquid sample.

A Study on Heat Transfer Performances of a Heat Pipe Heat Sink for Power Control Semiconductors (전력제어 반도체용 히트파이프 냉각기의 열전달 성능 연구)

  • 강환국;김재진;김철주
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.13 no.8
    • /
    • pp.701-709
    • /
    • 2001
  • In this days, heat pipe heat sink has been widely applied to power controllers for railway substations to remove heat from power semiconductors(diodes or thyristors). The heat pipe heat sink consists of a aluminum heating block for mounting the thyristor, 2~3 heat pipes and large number of aluminum fins. The present study was to get fundamental informations of the structure, design parameters and heat transfer performances of heat pipe heat sink. Series of operational test for a unit with 3 heat pipes were performed and its heat flow circuit was analysed from the experimentally obtained data on wall temperature distribution. Total resistance was ranged 0.02~$0.03^{\circ}C$/W for a power range from 40W to400W. The time to get the steady state was approximately longer than 20 minutes, and overshooting was not occurred during start up operation.

  • PDF

Low Temperature Fluidity Performance Evaluation of Composited Package Fuel Heater for Diesel Cars (디젤차량용 통합연료히터의 저온유동성 성능평가)

  • Lee, Jeong-Hwa;Park, Hyung-Won;Lee, Woong-Su;Lee, Young-Jea;Lee, Bo-Hee;Yoon, Dal-Hwan
    • Journal of IKEEE
    • /
    • v.18 no.1
    • /
    • pp.152-158
    • /
    • 2014
  • It is very important to supply the diesel fuel from fuel tank to combustion chamber in case of cold start procedure. the paraffin hydrocarbons are easily solidified at low fuel temperature and it can be blocking the fuel supply to the high pressure fuel pump. In order to reduce the fuel crystallization (Waxing), it have been used to develop not only cold flow additives but also the proper mounting design of fuel filter. Block heater in the fuel filter assembly have been also contained to improve the cold start and prevent blocking the fuel supply in Common Rail Direct Injection System. we can obtain the fuel pressure drop and fuel flow rate, power consumption of fuel heater to have the cold flow evaluation test with the saperated and composited fuel heater at the low ambient temperature, Due to evaluating cold flow performance of two block heater, we knew that composited package fuel heater was the excellent cold flow performance compared to separated type and obtained the parameters of cold flow.

Reliability study of 6-axis model surgery simulator for orthognathic surgery (6축 모형수술 시뮬레이터의 정확도에 관한 연구)

  • Jeon, Jae-Ho;Lee, Hyung-Chul;Ji, Hyun-Jin;Jeon, Yeong-Jin;Kim, Yong-Il;Son, Woo-Sung;Park, Soo-Byung;Kim, Sung-Sik;Whang, Dae-Seok
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • v.36 no.1
    • /
    • pp.23-27
    • /
    • 2010
  • The purpose of this study was to evaluate the reliability of 6-axis model surgery simulator (6AMSS) for orthognathic surgery. A rectangular parallelepiped plastic block was assembled to model-mounting plate of 6AMSS. Left-right (X), anterior-posterior (Y), up-down (Z) translation and pitching (${\phi}X$), rolling (${\phi}Y$) and yawing (${\phi}Z$) rotation was planned and performed using 6AMSS. The actual translation and rotation were measured with dial gauge and precisional protractor, respectively. Comparison between the planned and actual movements of plastic block for each variable were made using paired t- test. Statistical analysis for X, Y, Z, ${\phi}X$, ${\phi}Y$ and ${\phi}Z$ movement have shown no significant differences between planned and actual movement (P > 0.05). This indicate that model surgery performed with the aid of the 6AMSS is accurate in 3D translation and rotation. The 6AMSS is practically useful for accurate fabrication of surgical splint for orthognathic surgery.

High Quality Tissue Miniarray Technique Using a Conventional TV/Radio Telescopic Antenna

  • Elkablawy, Mohamed A.;Albasri, Abdulkader M.
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.3
    • /
    • pp.1129-1133
    • /
    • 2015
  • Background: The tissue microarray (TMA) is widely accepted as a fast and cost-effective research tool for in situ tissue analysis in modern pathology. However, the current automated and manual TMA techniques have some drawbacks restricting their productivity. Our study aimed to introduce an improved manual tissue miniarray (TmA) technique that is simple and readily applicable to a broad range of tissue samples. Materials and Methods: In this study, a conventional TV/radio telescopic antenna was used to punch tissue cores manually from donor paraffin embedded tissue blocks which were pre-incubated at $40^{\circ}C$. The cores were manually transferred, organized and attached to a standard block mould, and filled with liquid paraffin to construct TmA blocks without any use of recipient paraffin blocks. Results: By using a conventional TV/radio antenna, it was possible to construct TmA paraffin blocks with variable formats of array size and number ($2-mm{\times}42$, $2.5-mm{\times}30$, $3-mm{\times}24$, $4-mm{\times}20$ and $5-mm{\times}12$ cores). Up to $2-mm{\times}84$ cores could be mounted and stained on a standard microscopic slide by cutting two sections from two different blocks and mounting them beside each other. The technique was simple and caused minimal damage to the donor blocks. H&E and immunostained slides showed well-defined tissue morphology and array configuration. Conclusions: This technique is easy to reproduce, quick, inexpensive and creates uniform blocks with abundant tissues without specialized equipment. It was found to improve the stability of the cores within the paraffin block and facilitated no losses during cutting and immunostaining.

Design of a DC-DC Step-Down Converter for LED Backlight of Mobile Devices (휴대기기용 LED 백라이트를 위한 감압형 DC-DC 변환기 설계)

  • Son, Hyun-Sik;Lee, Min-Ji;Park, Won-Kyoung;Song, Han-Jung
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.15 no.3
    • /
    • pp.1700-1706
    • /
    • 2014
  • In this paper, a step down converter for LED backlight of mobile application has been proposed. The converter which is operated with 4 MHz high switching frequency is capable of reducing mounting area of passive devices consists of a power stage and a control block. Circuit elements of the power stage are inductor, output capacitor, MOS transistors and feedback resistors. The control block consists of pulse width modulator, error amplifier and oscillator etc. Proposed step down converter has been designed and verified using a $0.35{\mu}m$ 1-poly 4-metal BCD process technology. Simulation results show that the output voltage is 1.8 V in 3.7 V input voltage, output current 100 mA which is larger than 25 ~ 50 mA in conventional 500 KHz driven converter when the duty ratio is 0.4.

MNFS: Design of Mobile Multimedia File System based on NAND FLASH Memory (MNFS : NAND 플래시메모리를 기반으로 하는 모바일 멀티미디어 파일시스템의 설계)

  • Kim, Hyo-Jin;Won, You-Jip;Kim, Yo-Hwan
    • Journal of KIISE:Computer Systems and Theory
    • /
    • v.35 no.11
    • /
    • pp.497-508
    • /
    • 2008
  • Mobile Multimedia File System, MNFS, is a file system which extensively exploits NAND FLASH Memory, Since general Flash file systems does not precisely meet the criteria of mobile devices such as MP3 Player, PMP, Digital Camcorder, MNFS is designed to guarantee the optimal performance of FLASH Memory file system. Among many features MNFS provides, there are three distinguishable characteristics. MNFS guarantees, first, constant response time in sequential write requests of the file system, second, fast file system mounting time, and lastly least memory footprint. MNFS implements four schemes to provide such features, Hybrid mapping scheme to map file system metadata and user data, manipulation of user data allocation to fit allocation unit of file data into allocation unit of NAND FLASH Memory, iBAT (in core only Block Allocation Table) to minimize the metadata, and bottom-up representation of directory. Prototype implementation of MNFS was tested and measured its performance on ARM9 processor and 1Gbit NAND FLASH Memory environment. Its performance was compared with YAFFS, NAND FLASH File system, and FAT file system which use FTL. This enables to observe constant request time for sequential write request. It shows 30 times faster mounting time to YAFFS, and reduces 95% of HEAP memory consumption compared to YAFFS.

Ginsenoside (20S)Rg3 Ameliorates Synaptic and Memory Deficits in an Animal Model of Alzheimer's Disease

  • Kim, Tae-Wan
    • 한국약용작물학회:학술대회논문집
    • /
    • 2011.09a
    • /
    • pp.31-45
    • /
    • 2011
  • The amyloid ${\beta}$-peptide ($A{\beta}$), which originates from the proteolytic cleavage of amyloid precursor protein (APP), plays a central role in the pathogenesis of Alzheimer's disease (AD). Mounting evidence indicates that different species of $A{\beta}$, such as $A{\beta}$ oligomers and fibrils, may contribute to AD pathogenesis via distinct mechanisms at different stages of the disease. Importantly, elevation and accumulation of soluble $A{\beta}$ oligomers closely correlate with cognitive decline and/or disease progression in animal models of AD. In agreement with these studies, oligomers of $A{\beta}$ have been shown to directly affect synaptic plasticity, a neuronal process that is known to be essential for memory formation. Our previous studies showed that $A{\beta}$ induces the breakdown of phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), a phospholipid that regulates key aspects of neuronal function. PI(4,5)P2 breakdown was found to be a key step toward synaptic and memory dysfunction in a mouse model of AD. To this end, we seek to identify small molecules that could elevate the levels of PI(4,5)P2 and subsequently block $A{\beta}$ oligomer-induced breakdown of PI(4,5)P2 and synaptic dysfunction.. We found that (20S)Rg3, an active triterpene glycoside from heat-processed ginseng, serves as an agonist for phosphatidylinositol 4-kinase IIalpha (PI4KIIalpha), which is a lipid kinase that mediates a rate-limiting step in PI(4,5)P2 synthesis. Consequently, (20S)Rg3 stimulates PI(4,5)P2 synthesis by directly stimulating the activity of PI4KIIalpha. Interestingly, treatment of a mouse model of AD with (20S)Rg3 leads to reversal of memory deficits. Our data suggest that the PI(4,5)P2-promoting effects of (20S)Rg3 may help mitigate the cognitive symptoms associated with AD.

  • PDF

RFFS : Design of a Reliable NAND Flash File System for Embedded system (임베디드 시스템을 위한 신뢰성 있는 NAND 플래시 파일 시스템의 설계)

  • Lee Tae-hoon;Park Song-hwa;Kim Tae-hoon;Lee Sang-gi;Lee Joo-Kyong;Chung Ki-Dong
    • The KIPS Transactions:PartA
    • /
    • v.12A no.7 s.97
    • /
    • pp.571-582
    • /
    • 2005
  • NAND flash memory has advantages of non-volatility, little power consumption and fast access time. However, it suffers from inability that dose not provide to update-in-place and the erase cycle is limited. Moreover, the unit of read and write operations is a page. A NAND flash file system called YAFFS has been proposed. But YAFFS has several problems to be addressed. In this paper, the Reliable Flash File System(RFFS) for NAND flash memory is designed and evaluated. In designing a file system the following four issues must be considered in particular for the design: (i) to minimize a repairing time when the system fault occurs, (ii) to balance the number of block erase operations by offering wear leveling policy, and (iii) to reduce turnaround time of memory operations by reducing the amount of data written. We demonstrate and evaluate the performance of the proposed schemes.