• Journal of the Microelectronics and Packaging Society
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• v.18 no.3
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• pp.33-37
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• 2011

In this study, the degradation mechanism of mounted chip resistors with Ag-epoxy isotropic conductive adhesives (ICAs) under the humidity exposure ($85^{\circ}C$/85%RH) was examined by electrical resistance change and microstructural study. The effect of the chloride content in Ag-epoxy ICA on joint stability was also examined. The increasing range of the electrical resistance in the typical ICA joint was greater than that in the low Cl content ICA joint. In the case of the typical ICA joint, Sn oxides such as SnO, $SnO_2$, and Sn-Cl-O were formed inhomogeneously on the surface of the Sn plating during the $85^{\circ}C$/85%RH test. In contrast, no Sn-Cl-O was found in the low Cl content ICA joint during the $85^{\circ}C$/85%RH. It is suggested that Cl in Ag-epoxy ICA accelerate the electrical degradation of Sn plated chip components joined with Ag-epoxy ICA.

• Applied Biological Chemistry
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• v.42 no.3
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• pp.223-228
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• 1999

The storage effects of satsuma mandarin(Citrus unshiu Marc. var. miyagawa) by humidity control during storage; 90% relative humidity (RH) and 85% RH at $3^{circ}C$, and room temperature were investigated. After 98 days' storage, weight losses were 3.40% for 90% RH, 6.92% for 85% RH, and 11.87% for room temperature storage. Decay ratio was increased rapidly from 3.87% on 98 days' to 48.75% on 126 days' storage for 90% RH. Soluble solids and flesh ratio were declined gradually, but the differences were not significantly. Firmness of fruits was continuously reduced during storage, especially on room temperature storage by the softening of the fruits. Acid content and vitamin C were gradually reduced during storage. Coloration was continuously progressed on room temperature, compared to cold storage. In order to keep freshness of the fruits, optimum storage period of early variety of Satuma mandarin was regarded for 100 days at $3^{circ}C$, 85% RH on the basis of sensory evaluation and chemical compositions.

• Journal of the Microelectronics and Packaging Society
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• v.18 no.3
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• pp.45-52
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• 2011

It is known that test methods to evaluate solder joint reliability are die shock test, die shear test, 3points bending test, and thermal shock test. The present study investigated the effects of failure mode on 3 types (as-reflowed, $85^{\circ}C$/85%RH treatment, and $150^{\circ}C$/10hr aging) of solder joints for flip-chip BGA package by using various test methods. The test methods and configurations are reported in detail, i.e. die shock, die shear, 3points bending, and thermal shock test. We focus on the failure mode of solder joints under various tests. The test results indicate that die shock and die shear test method can reveal brittle fracture in flip-chip ball grid array (FCBGA) packages with higher sensitivity.

• Food Science and Preservation
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• v.6 no.2
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• pp.143-147
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• 1999

Onions were subject to quality evaluation from the physiological and physicochemical points of view during storage under different conditions, which were low temperature (2-4$^{\circ}C$, 80% RH), pit temperature (3-15$^{\circ}C$, 75-85% RH), room temperature (10-23$^{\circ}C$, 75-98% RH) and ambient temperature (2-25$^{\circ}C$, 62-72% RH). Sprouting were dereloped from the 11th month of storage in low temperature. Rotting was quickly occurred from the 7th month of storage excepting onions in room temperature. Low temperature storage showed the least weight change. Moisture content increased with the lapse of storage time at both low temperature and pit temperature storage conditions, but decreased with the lapse of storage time at room and ambient temperature conditions. Total and reducing sugars decreased with the storage time, while vitamin increased in stored onions at low temperature.

• Journal of the Korean Wood Science and Technology
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• v.34 no.2
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• pp.22-29
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• 2006

On purpose to reduce accumulated moisture and to prevent moisture condensation in a light-frame wall, thermal characteristics and moisture behaviors were investigated for four different wall assemblies; a) typical wall, b) addition of vapor retarder between the insulation and the gypsum board, c) addition of air gap for natural ventilation behind the siding, d) composition with b) and c). Each wall was tested under two climate conditions; 1) $20^{\circ}C$, 50% RH (indoor) and $30^{\circ}C$, 85% RH (outdoor), 2) $30^{\circ}C$, 85% RH (indoor) and $20^{\circ}C$, 50% RH (outdoor).The results showed that the typical wall assembly had poor resistance against moisture intrusion from the inside of building. Outdoor and indoor humidity caused the moisture condensations on the inside of the siding and the back surface of the sheathing respectively. The addition of a vapor retarder did not give significant improvement in preventing the moisture intrusion.

• Journal of Bio-Environment Control
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• v.18 no.4
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• pp.385-392
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• 2009

This study was performed to evaluate the influence of temperature, relative humidity, and light conditions during healing and acclimatization on the graft-take and growth of grafted peppers (Capsicum annuum L.), in order to propose optimum environmental conditions for the healing and acclimatization of grafted peppers. The healing and acclimatization period was for six days and was divided into three stages (Stage I, II and III), of which each period was two days. Grafted peppers were healed under the condition of 30 and 95% relative humidity (RH) during Stage I. During Stage II and III, grafted peppers were healed and acclimatized under different temperatures ($20^{\circ}C$, $25^{\circ}C$, or $30^{\circ}C$) and RH conditions (75%, 85% or 95%). The growth of grafted peppers was greater under lower temperature and lower relative humidity conditions. The graft-take just after the end of healing and acclimatization was greater grafted peppers under high RH condition. However, the graft-take of peppers which were healed and acclimatized under $30^{\circ}C$ and RH 95%, dropped by about 10 percent on day seven after healing and acclimatization. And also, grafted peppers were healed and acclimatized under the different temperatures ($25^{\circ}C$ or $30^{\circ}C$), RH conditions (65%, 75% or 85%), and light condition (dark or light). Lower RH (to 65%) and light condition at $25^{\circ}C$ during healing and acclimatization promoted the graft-take and growth of grafted peppers.

• Journal of Welding and Joining
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• v.33 no.3
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• pp.47-53
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• 2015

By the trends of electronic package to be more integrative, the fine Cu trace pitch of organic PCB is required to be a robust design. In this study, the short circuit failure mechanism of PCB with a Cl element under the Temperature humidity bias test ($85^{\circ}C$/85%RH/3.5V) was examined by micro-structural study. A focused ion beam (FIB) and an electron probe micro analysis (EPMA) were used to polish the cross sections to reveal details of the microstructure of the failure mode. It is found that $CuCl_x$ were formed and grown on Cu trace during the $170^{\circ}C$/3hrs and that $CuCl_x$ was decomposed into Cu dendrite and $Cl_2$ gas during the $85^{\circ}C$/85%RH/3.5V. It is suggested that Cu dendrites formed on Cu trace lead to a short circuit failure between a pair of Cu traces.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1989.06a
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• pp.111-113
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• 1989

This paper reports the optical characteristics of TeS$_{5}$ Ge$_{5}$ thin film. In phase diagram, TeS$_{5}$ Ge$_{5}$ has the eutetic point with the loweat melting point. Therfore, TeS$_{5}$ Ge$_{5}$ thin film will be melted by Diode Laser with low energy. TeS$_{5}$ Ge$_{5}$ thin films start to change the phase from amorphous to crystalline near 10$0^{\circ}C$, but perfectly change the phase at 28$0^{\circ}C$. As-deposit TeS$_{5}$ Ge$_{5}$ thin film start to change the phase to crystalline in enviroment og 66$^{\circ}C$ 80%RH.circ}C$ 80%RH.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.420-425
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• 1986

This study was conducted to investigate the influence of air temperature and relative humidity on excessive drying rate of burley tobacco. In experiment I, 4 temperatures and I humidity by day and air curing by night were treated from initial curing stage. In experiment II, 15 combinations of 3 temperatures and 5 humidities were applied from the yellow stage of cure. Yellowish cured leaves resulted from overdrying at high temperature and especially, at low humidity. How- ever, these were not produced at 75-80% RH and under 35$^{\circ}C$ by day with air curing b y night. The proper range of temperature and humidity for desirable color of cured leaf were the combinations of 30$^{\circ}C$, 75-80% RH or 35$^{\circ}C$, 80-85% RH. As excessive drying leaves increased, physical properties of cured leaves were poorer and chemical contents were less decomposed.

• Korean Journal of Materials Research
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• v.3 no.6
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• pp.598-605
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• 1993

Methacryloxyethyl dimethyl alkyl($C_{1}\sim C_{12}$, benzyl and 2, 2-diethoxy ethyl) ammonium bromide monomers were prepared to investigate the relative humidity characteristics for polymer electrolytes with different chemical structures. They were coated on the alumna substrate printed comblike gold electrode by photopolymerization after micro-syringe injection. As the thickness of rhe humid membrane increased, the impendance decreased, whereas the impedance ~ncreased as the carbon cham of alkyl substituent in the monomer increased. The impendance of the polymeric electrolytes with $C_6\sim C_8$ substituents were varied from 19M$\Omega$ to 5K$\Omega$ for the range of 30-90% Mi. The temperature depedence coefficient in the range of 15-$35^{\circ}C$ was found to be -0.45% $RH/^{\circ}C$and the hysteresis falled within the range of $\pm$2% RH. The response time was 35 second for varying humldity from 33% to 85% RH.