• Journal of the Korean Society of Safety
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• v.25 no.6
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• pp.14-21
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• 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.

• Journal of the Korean Society for Precision Engineering
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• v.7 no.2
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• pp.58-64
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• 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.

• Reproductive and Developmental Biology
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• v.29 no.3
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• pp.149-154
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• 2005

The purpose of this study was the analysis of sperm ability in Specific Pathogen Free (SPE) miniature pig for production of bio-organ. The collected semen was diluted with extender and stored at $17^{\circ}C$t for up to 7 days. The semen samples were evaluated at 0, 1, 3, 5, and 7 days of storage for analysis of sperm ability. Sperm ability was evaluated by examining viability, progressive motility, sperm abnormality and intensity of the sperm membrane. Also, the semen was processed according to the convenient freezing method, and frozen-thawed sperm was evaluated by examining viability, capacitation and acrosome reaction using chlortetracycline (CTC) staining. Motility of spermatozoa of SPF miniature pig was significantly (P<0.05) lower on 3 days or later compared to the Duroc, Yorkshire and Landrace in domestic boar. The percentage of abnormal spermatozoa of Landrace were significantly (P<0.05) higher than in SPF miniature pig, Duroc and Yorkshire that had a similar percentage on 5 or 7 days of sperm storage. The percentage of spermatozoa with coiled tail decreased during the storage period but there were no significant difference. On the other hand, viability of frozen-thawed spermatozoa had a significantly (P<0.05) lower in SPF miniature pig than in other domestic boars. CTC patterns had no significant difference, but SPF miniature pig had higher percentage of capacitated spermatozoa and lower percentage of acrosome-reacted it than domestic boars. Therefore, this study suggest that it is necessary to develop the suitable extender and freezing methods methods for the high viable rate and fertilizing ability in vitro.

• Reproductive and Developmental Biology
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• v.38 no.1
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• pp.53-62
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• 2014

The objective of this study was to investigate the relationship between fertility and protein pattern change using in vitro fertilization, analysis of sperm characteristics and two-dimensional gel electrophoresis in different pig types. In results, the viability and mitochondria integrity of sperm were higher significantly (p<0.05) but the portions of acrosome reaction was lower significantly (p<0.05) in Duroc and $F_1$ (potbellied ${\times}$ PWG miniature pig) than PWG miniature. On in vitro fertilization to investigate fertility, the fertility of $F_1$ semen war higher significantly (p<0.05) than in Duroc and PWG miniature pig. On the other hand, protein patterns showed similar function among the different boar semen. Especially, the heat shock 70 kDa 1-like and G patch domain-containing protein 4 were significantly (p<0.05) higher expressed in $F_1$ than in Duroc and PWG miniature pig. The proteins associated with mitochondria in Duroc were significantly (p<0.05) higher expressed than in $F_1$ and PWG miniature pig. The developmental rates to blastocyst stage of oocytes fertilized with sperm of $F_1$ pig were significantly (p<0.05) higher than in PWG miniature pig. However, phosphoglycerate kinase 2 and zinc finger protein 431 were significantly (p<0.05) higher expressed in PWG miniature pig than in $F_1$ and Duroc pigs. In conclusion, the results of the present study indicate that different proteins were expressed in different pig types, and were associated with a sperm functions and embryo development.

• Journal of Veterinary Clinics
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• v.26 no.3
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• pp.303-305
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• 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.

• Journal of Embryo Transfer
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• v.21 no.3
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• pp.263-271
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• 2006

The purpose of this study was undertaken to compare ability of frozen-thawed sperm characteristics between two strains (miniature pig and Duroc). The semen was collected by gloved-hand method into a pre-warmed ($37^{\circ}C$) thermos bottle. The semen was diluted with same volume extender and added to LEY solution for freezing. The diluted semen was placed in 0.5 ml straws, and freezing was initiated by exposing the straws to liquid nitrogen ($LN_2$) vapours for 10 min before placing them into $LN_2$ for cryopreservation. The frozen-semen straw were thawed at 20, 37 and $50^{\circ}C$ for 1 min, 45 sec and 10 sec within water-bath. The semen sample were evaluated at 0, 3, 6, 9, and 12 h after incubation at $37^{\circ}C$ for analysis of sperm ability. Abnormality of spermatozoa in miniature pig was significantly (p<0.05) higher than that in Duroc at 0, 9 and 12 h of post-thawing incubation after frozen-thawing. The percentage of F-patterned spermatozoa in miniature pig was significantly (p<0.05) lower, while the percentage of AR (acrosome reacted spermatozoa) pattern was higher in the miniature than in the Duroc. On the other hand, there was no significant difference in the viability of spermatozoa thawed at different temperature ($20^{\circ}C\;and\;37^{\circ}C$) between two species, but the viability in miniature pig was higher (p<0.05) than in Duroc when sperm was thawed at $50^{\circ}C$. In conclusion, this study suggest that suitable freezing method for miniature pig semen is required for increasing post-thawing viability and fertilization capacity.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.1
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• pp.19-24
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• 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.

• Reproductive and Developmental Biology
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• v.40 no.1
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• pp.1-5
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• 2016

This study investigated the effects of L-carnitine (LC) and nicotinic acid (NA) on sperm viability during liquid storage at $18^{\circ}C$ in miniature pigs. $10{\mu}M$ LC and 30 mM NA, combined LC and NA (LN) were treated in fresh semen for 3, 7, and 10 days. In results, sperm survival increased in NA- and LN-treated semen on 7 and 10 days (p<0.05), mitochondrial integrity of live sperm increased in LN-treated semen on 7 days (p<0.05), but not NA-treated semen. In addition, we examined the acrosome reaction of sperm in miniature pigs. LC and NA did not influence on acrosome reaction of boar sperm. In conclusion, LC and NA effectively maintained the viability and quality of sperm during long-term storage in miniature pigs, suggesting that the combined LN may be useful for improving the semen extender for long-term liquid storage in pigs.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.517-520
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• 2002

Stereoscopic particle image velocimetry is a measurement technique to acquire of three dimensional velocity field by two cameras. With a laser sheet illumination, the third velocity component can be deduced by out-of-plane velocity components using a stereoscopic matching method. Industrial fluid flows are almost three dimensional turbulent flows, so it is necessary to use the stereoscopic PIV measurement method. However the existing stereoscopic PIV system seems hard to use since it is very expensive and complex. In this study we have developed a Stereoscopic Miniature PIV(MPIV) system based on the concept of the Miniature PIV system which we have already developed. In this paper, we address the design and some first experimental results of the stereoscopic PIV system. The Stereoscopic MPIV system features relatively modest performances, but is considerably smaller, cheaper and easy to handle. The proposed Stereoscopic MPIV system uses two one-chip-only CMOS cameras with digital output. Only two other chips are needed, one for a buffer memory and one for an interfacing logic that controls the system. Images are transferred to a personal computer (PC) via its standard parallel port. No extra hardware is required (in particular, no frame grabber board is needed).

• Journal of the Microelectronics and Packaging Society
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• v.11 no.3 s.32
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• pp.83-89
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• 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.