• Title/Summary/Keyword: miniature

Search Result 813, Processing Time 0.036 seconds

Miniature Biochip Fluorescence Detection System with Spatial Separation of Fluorescence from Excitation Light (형광과 여기광을 공간적으로 분리하는 바이오칩용 소형 형광측정시스템)

  • Kim Ho-seong;Choi Jea-ho;Park Ju-han;Lee Kook-nyung;Kim Yong-Kweon
    • The Transactions of the Korean Institute of Electrical Engineers C
    • /
    • v.54 no.8
    • /
    • pp.378-383
    • /
    • 2005
  • We report the development of miniature fluorescence detection systems that employ miniature prism, mirrors and low coat CCD camera to detect the fluorescence emitted from 40 fluorescently-labeled protein patterns without scanner. This kind of miniature fluorescence detection system can be used in point of care. We introduce two systems, one uses prism+mirror block and the other uses prism and two mirrors. A large NA microscope eyepiece and low cost CCD camera are used. We fabricated protein chip containing multi-pattern BSA labeled with Cy5, using MEMS technology and modified the surface chemically to clean and to immobilize proteins. The measurements show that the combination of prism and mirrors can homogenize elliptical excitation light over the sample with higher optical efficiency, and increase the separation between excitation and fluorescence light at the CCD to give higher signal intensity and higher signal to noise ratio. The measurements also show that protein concentrations ranging from 10 ng/ml to 1000 ng/ml can be assayed with very small error. We believe that the proposed fluorescence detection system can be refined to build a commercially valuable hand-held or miniature detection device.

Otitis Externa caused by Malassezia furfur in a Miniature Pig (애완 미니 돼지의 Malassezia furfur에 의한 외이도염 증례)

  • Han, Jae-Ik;Na, Ki-Jeong
    • Journal of Veterinary Clinics
    • /
    • v.26 no.3
    • /
    • pp.303-305
    • /
    • 2009
  • A 7-month-old, female miniature pig was presented with excessive cerumen and pruritus. Greasy brown cerumen in both exteranal ear canal and sporadic head shaking were observed in the physical examination. Numerous budding yeasts in the cerumen were examined on microscopic examination. For species identification, PCR-RFLP using incubated colony on modified Dixon's medium was performed and finally, causative yeast was identified as M. furfur.

Torque ripple Reduction of High speed Minituale BLDC using instantaneous voltage control (초고속 소형 BLDC의 순시전압 제어에 의한 토크 리플 억제)

  • Lee, Dong-Hee;Kim, Tae-Hyoung;Ahn, Jin-Woo;Won, Tae-Hyun
    • Proceedings of the KIEE Conference
    • /
    • 2006.04b
    • /
    • pp.91-94
    • /
    • 2006
  • Miniature BLDC is widely used in industrial applications and especially medical appliances because of there character that high driving efficiency and high torque characteristic. However torque ripple of a high speed miniature BLDC is serous in switching period cue to the very electrical time constant. This paper present instant voltage and current control for torque ripple reduction of a high speed miniature BLDC. Computer simulation and experiment test for 40,000 rpm miniature BLDC show the verification of the proposed control method.

  • PDF

Development of a Miniature Air-bearing Stage with a Moving-magnet Linear Motor

  • Ro, Seung-Kook;Park, Jong-Kweon
    • International Journal of Precision Engineering and Manufacturing
    • /
    • v.9 no.1
    • /
    • pp.19-24
    • /
    • 2008
  • We propose a new miniature air-bearing stage with a moving-magnet slotless linear motor. This stage was developed to achieve the precise positioning required for submicron-level machining and miniaturization by introducing air bearings and a linear motor sufficient for mesoscale precision machine tools. The linear motor contained two permanent magnets and was designed to generate a preload force for the vertical air bearings and a thrust force for the stage movement. The characteristics of the air bearings, which used porous pads, were analyzed with numerical methods, and a magnetic circuit model was derived for the linear motor to calculate the required preload and thrust forces. A prototype of a single-axis miniature stage with dimensions of $120\;(W)\;{\times}\;120\;(L)\;{\times}\;50\;(H)\;mm$ was designed and fabricated, and its performance was examined, including its vertical stiffness, load capacity, thrust force, and positioning resolution.

Evaluation of Shear Strength of a Miniature Lead-free Single Solder Ball Joint (초소형 무연 단일 솔더볼 연결부의 전단강도 평가)

  • Joo, Se-Min;Kim, Ho-Kyung
    • Journal of the Korean Society of Safety
    • /
    • v.25 no.6
    • /
    • pp.14-21
    • /
    • 2010
  • A miniature single solder ball joint is designed to mimic the actual solder joints used in the micro-electric industries. Shear tests were conducted to evaluate the mechanical behavior of miniature single solder joints at intermediate strain rates from $0.019\;s^{-1}$ to $2.16\;s^{-1}$ at room temperature. The shear fracture strength of the present solder ball joints generally increased with increasing shear strain rate, ranging from 32 to 51MPa. This behavior is affected by the sensitivity of bulk solder strength to strain rate. Shear fracture mode changed from brittle to partial ductile (failure inside the bulk solder) with an increase of shear speed. The unloading shear fracture toughness is generally consistent with the measure of the amount of bulk solder on the fractured surface.

Calculation of rated output in diaphragm type miniature load cell (다이아프램 감지부 구조를 갖는 소형 로드셀의 정격출력 계산에 관한 연구)

  • Kwon, Young-Ha;Kang, Dae-Im;Joo, Jin-Won
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.7 no.2
    • /
    • pp.58-64
    • /
    • 1990
  • As the miniature load cells have small inner space and sensing elements of which are thin and very sensitive to manufacturing conditions, it is very difficult to predict the rated outputs and control them by using the compensation resistor. The very useful equation has been derived for calculation of theoretical rated outputs for diaphragm type miniature load cells when commercial diaphragm strain gages are used. Four diaphragm type miniature load cells of which capacities are from 300 N to 1, 000 N and outer diameters are 20 mm and 26.5 mm are manufactured. The differences between calculating results and actural ones are less than 5%. According to numerical analysis the decrease of rated outputs caused to main error is examined in existence of loading button.

  • PDF

Fabrication of NTC thermistor embedded Miniature Thermoelectric Cooling Module for Temperature Control (NTC 써미스터가 내장된 항온 제어용 소형 열전 냉각 모듈 제조)

  • Park J. W.;Choi J. C.;Hwang C. W.;Choi S. C.
    • Journal of the Microelectronics and Packaging Society
    • /
    • v.11 no.3 s.32
    • /
    • pp.83-89
    • /
    • 2004
  • NTC thermistor embedded miniature thermoelectric module was fabricated for the precise temperature control of optical communication device such as laser diode (LD). The miniature thermoelectric module ($7.2 mm{\times}9 mm{\times}2.2 mm$) consists of 21 BiTe thermoelectric couples, the operating temperature is precisely controlled by embedded thermistor with quick response. The figure-of-merit (Z), maximum temperature difference (${\Delta}T_{max}$), maximum cooling capacity ($Q_{max}$) of the miniature thermoelectric module were $2.5{\times}10^{-3}$/K, 72 K, 2.2 W respectively and temperature could be controlled in range of ${\pm}0.1^{\circ}C$ accuracy in air. The fabricated miniature thermoelectric module is suitable for applications of the optical communication packaging.

  • PDF

Determination of Undrained Shear Strength using Miniature Cone and T-bar Penetrometers for Kaolin Clay (소형콘과 T-bar 관입기를 이용한 카올린 점토의 비배수전단강도 산정에 관한 연구)

  • Sespene, Shemelyn;Choo, Yun Wook
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.38 no.3
    • /
    • pp.429-438
    • /
    • 2018
  • Cone and T-bar penetrometers have been frequently used to estimate the undrained shear strength of clay. For small-size model tests, miniature penetrometers should be used but their correlation factors have not been well published. In this study, a testing setup was developed to derive empirical factors of the miniature cone and T-bar penetrometers. A 350mm-diameter chamber and kaolin clay were utilized to prepare soil specimens consolidated under four different pre-consolidation pressures controlling undrained shear strength. Two miniature cones with two diameters of 10-mm and 16-mm and a T-bar penetrometer with 10-mm diameter were used to investigate boundary effect, penetration rate effect, and diameter and shape effect. Unconsolidated-undrained triaxial tests were carried out with samples taken from the specimens to measure undrained shear strength. Finally, empirical factors for the penetrometers were constructed to correlate tip resistance to undrained shear strength.

Effect of Cholesterol and Serum Albumin on Sperm Ability and Lipid Peroxidation during the Storage of Miniature Pig Sperm (미니돼지정액의 보존 시 콜레스테롤과 혈청 알부민이 정자 성상과 지질 과산화에 미치는 영향)

  • Kim, Dong-Woo;Lee, Yong-Seung;Yoo, Han-Jun;Cheong, Hee-Tae;Yang, Boo-Keun;Park, Choon-Keun
    • Journal of Embryo Transfer
    • /
    • v.26 no.1
    • /
    • pp.71-78
    • /
    • 2011
  • This study was undertaken to find out the effect of cholesterol and serum albumin on sperm ability and lipid peroxidation levels period to the liquid storage of miniature pig sperm. Ejaculated semen from miniature pigs was collected by gloved-hand method into a pre-warmed ($37^{\circ}C$) thermos bottle, and extended with Modena solution {with and without BSA, methyl-beta-cyclodextrin (-cholesterol) and cholesterol loaded cyclodextrin (+cholesterol)}. Each semen was assessed for viability (SYBR-14/PI staining) and acrosome intactness, intensity and capacitation status by chlorotetracycline (CTC) staining at 1, 3, 5, 7 and 10 days of storage. At for the effects of cholesterol and serum albumin on lipid peroxidation, semen were incubated with $H_2O_2$ ($10\;{\mu}M$), and lipid peroxidation level were measured by flow cytometry using the lipid peroxidation reporter probe $C_{11}-BODIPY^{581/591}$. The result, lipid peroxidation level in sperm added with cholesterol were lower in $10\;{\mu}M$ $H_2O_2$ compared to the added sperm with serum albumin. Also, added cholesterol to sperm had significant (p<0.05) higher viability when storage for 7 and 10 days and lower when 10 days of storage percentage of acrosome-reacted sperm (AR pattern) in acrosome state as say result compared to other treated groups. In conclusion, role of cholesterol during lipid storage in miniature pig spermatozoa was protected boar spermatozoa from lipid peroxidation prior to lipid storage. Addition serum albumin during lipid storage in sperm may be induce sperm membrane damage by lipid peroxidation. Therefore, addition of cholesterol to miniature pig sperm will be lead to extension of liquid storage periods.