• 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.

• Journal of Environmental Science International
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• v.17 no.11
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• pp.1227-1233
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• 2008

The effect of freeze drying and fixatives in post-treating freeze drying on the morphological properties of the rose (Rosa hybrida L.) petal were investigated for the production of high quality of freeze dried rose. The morphology including form and color of the dried flowers of cut rose were depended on the drying methods. The drying time was extended due to their density and water content, and was shorter in the freeze drying than that in the natural and hot air drying. Freeze dried process for dried flowers took 2 days in a freeze dryer and did not cause shrinkage or toughening of rose petal being dried, preserving its natural shape and color. The diameter of freeze dried flowers showed little reduction compared to fresh flowers. In Hunter color values of petals of freeze dried flowers, L and a values were high and showed little variations in comparison to fresh petals. Freeze drying led to a noticeable increase in anthocyanin contents in petals, suggesting that anthocyanin contents play an important role in the acquisition of freezing tolerance. Exposure of flowers to freeze drying was accompanied by an increase in the carotenoid content. In the post-treating freeze drying, epoxy resin, a fixative, applied alone or in combination to petals of freeze dried flowers showed efficient coating for the protection from humidity and sunlight. Combined application of epoxy and acetone to freeze dried petals permitted maintenance of natural color and excellent tissue morphology, showing color stability and shiny texture in surface of petals. These findings suggest that application of fixatives to freeze dried rose petals improves the floral preservation and epoxy coating provides good quality in the freeze dried flower product.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.6
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• pp.1493-1498
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• 2015

The autofocus system is automatically to drive the focus. It is very important to computer vision system. In the case of a compact camera, the actuator technology is used for auto-focus in mass production. the position sensor is required, the circuit configuration and easy method is widely used in VCM, compared to the stability of the drive size and the noise is a big stepping motor type, size has a piezo system having a humidity problem and the small leaded vulnerability. In addition, there is a liquid lens system, the advantages of low power in a compact structure but also a structure with proven quality and reliability and features required pressure. In this paper, we implement two control systems that can control the actuator as a liquid range of VCM using a sharpness of the image acquired by the image sensor automatically initiates 5Mpixel class was the implementation verification of focusing.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.3
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• pp.357-361
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• 2009

This study performed analysis on the thermal pattern and current characteristics of an LED ((Light Emitting Diode) street lamp. It did this using a TVS (Thermal Video System) to analyze the LED street lamp's thermal pattern, and measured its characteristics using an oscilloscope. The ambient temperature and humidity during the experiment were maintained at $24{\pm}2[^{\circ}C]$ and 50~60[%]. The capacity of the LED street lamp was 120[W] and nine sets of modules were arranged at uniform intervals. On one module, 24 LED lamps were arranged in a radial pattern. The analysis of the thermal diffusion pattern at the front of the LED lamp showed that the maximum surface temperature was approximately $34[^{\circ}C]$. In addition, there was almost no change in the temperature of the upper cover, and the temperature at the side showed a uniform thermal diffusion pattern. The surface temperature of the converter converting AC to DC increased to approximately $46[^{\circ}C]$. The analysis results of the thermal characteristics of one LED indicated uniform thermal characteristics for an initial eight minutes. However, the temperature at the center of the LED increased to approximately $82[^{\circ}C]$ after 12 minutes had elapsed. It can be seen from this that the temperature at the center of the LED was higher than the allowable temperature, $70[^{\circ}C]$ of the insulating material for general electrical devices. Therefore, it is necessary to design a lamp in such a way that the plastic insulating material does not come into contact with or get close to the LED lamp. The voltage of the LED lamp converted by the AC/DC converter was measured at DC 27[V] and the current was DC 13[A]. Consequently, it can be seen that in order to secure an adequate light source, it is important to supply a stable current that was greater than the current of other light sources. Therefore, appropriate radiation of heat is required to secure the stability and reliability of the system.

• Journal of Conservation Science
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• v.19
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• pp.85-98
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• 2006

Rock property of the Seosan Maaesamjonbulsang is composed of biotite granite with medium grained texture. The triad Buddha is highly deteriorated by the joint, fracture, break-out, exfoliation, dew condensation of the surface and discoloration of the secondary pollutant. Host rock of the triad Buddha is divided dozens of rock blocks with various shape, and developed irregular discontinuity planes. Besides, the host rock is promoted biological pollution due to the surrounding crowded vegetation and high humidity environment. As the results of structural stability, it is confirmed that developed discontinuity system in the host rock is exposed instability sloping environment. Therefore, the host rock and surroundings are required maintenance, and required preservation by continuance monitoring for understand behavior of discontinuity system.

• Journal of Conservation Science
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• v.16 s.16
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• pp.110-118
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• 2004

In order to evaluate two-step treatment of PEG-freeze drying for highly-degraded waterlogged ash woods (Fraxinus PP.; ca. 5,700 BP), which were excavated from peat lands in western Korea, dimension stability was examined during 45 months after complete treatment. The samples pre-treated with PEG in water solution showed better dimensional stabilities than the ones with PEG in t-butanol(TBA) solution. It suggests that TBA reduced the flexibility of wood cells and overflying by TBA induced micro-checks during freeze drying. Micro-checks results in fragile wood structures and consequently, large shrinkage by moisture absorbances of high PEG contents during exposure in humid condition. The results suggest that PEG in water-solution treatment is better than PEG in t-butanol as pretreament for freeze drying of highly-degraded waterlogged ash woods.

• Journal of Haehwa Medicine
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• v.14 no.2
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• pp.113-126
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• 2005

Atopic dermatitis(AD) is a chronic disease that affects the skin. "Atopic" refers to a group of diseases where there is often an inherited tendency to develop other allergic conditions, such as asthma and hay fever. In AD, symptoms vary from person to person. The most common symptoms are dry, itchy skin and rashes on the face, inside the elbows and behind the knees, and on the hands and feet. Although AD may occur at any age, it most often begins in infancy and childhood. The cause of AD is not known, but the disease seems to result from a combination of hereditary and environmental factors along with malfunction of the body's immune system. In contrast to that, the results from literatual study in oriental medicine are as follows; 1. The causes of AD are considered to be Mosusigisadok(母受時氣毒), Waegampoongsubyeol(外感風濕熱), Guasiksinlayeolmul(過食辛辣熱物), Ohbokonje(誤服溫劑). 2. The symptoms are fever, flushed face, red eyes, oliguria, constipation and itching. 3. Chungyeolhaedok(淸熱解毒) would be the basic method of treatment, and it divides into two categories; Subhyung(濕型) and Gunhyung(乾型). In Subhyung(濕型), AD is treated by Josub(燥濕), Chungyeol(淸熱) and Jiyang(止痒) whereas Chungyeol(淸熱), Jiyang(止痒), Jesub(除濕) in Gunhyung(乾型). 4. To prevent further damage and enhance quality of life, it is necessary to keep the temperature and humidity favorable, and healing the skin and keeping it healthy are important. Developing and sticking with a daily skin care routine is critical to preventing flares. Changing the diet and psychological stability may also be helpful to relieve symptoms of AD.

• Journal of Life Science
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• v.12 no.5
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• pp.535-543
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• 2002

To investigate the possibility of processing semi-dried jellyfish and to examine its keeping quality, the factors such as moisture content, pH, volatile basic nitrogen (VBN), viable cell counts, color value and texture were analyzed. For processing of the semi-dried product, optimum conditions of drying temperature and drying time were $25^{\circ}C$ and 90min, respectively, under 60 $\pm$ 5% of relative humidity and 2 m/sec of air blast speed. The shelf-life of the products, vacuum-packing method in nylon/polyethylene/linear low density polyethylene (0.015/0.045/0.040 mm) laminated film bag was at least 6 weeks during storage at 4$^{\circ}C$, while that of air packaged one was at least 4 weeks. In case of 2$0^{\circ}C$ storage the shelf-life of the products was at least 3 weeks in both air and vacuum packaged ones.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.25 no.4 s.34
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• pp.123-131
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• 1999

Liquid crystal known as a rheological barrier to coalescence of oil droplets, increases emulsion stability, water-holding capacity and promotes active material penetration to skin. Some investigation for its rheological characteristics have been reported but its relations to consumer perception have been rarely published. In this study, oil/water emulsion and oil/liquid crystal/water systems were manufactured using the same composition or Behenyltrimethylammonium chloride/Cetostearyl alcohol/Lanolin oil. and rheological properties or each system were investigated with Cone and Plate rheometer. The formation of liquid crystalline phase was observed with polarized microscope and Differential Scanning Calorimeter. Continuous shear experiment, creep, yield and water holding capacity were measured for oil/water and oil/liquid crystal/water systems. The results were compared with sensory evaluations. Oil/liquid crystal/water system showed higher,viscosity at the same shear rate. higher viscoelasticity and higher yield stress than oil/water system. These properties were expected to show good spreadability and excellent richness without waxiness in hair can: products of creme type. This expectation was consistent with the results of sensory experiments. Water-holding capacity was evaluated by measuring residual water of specimens at specific temperature and relative humidity. Oil/liquid crystal/water system was proved to have higher ability to hold water in comparison with oil/water system. The results indicated that oil/liquid crystal/water system was of benefit to rheological properties creme type hair care products.

• Journal of the Korean earth science society
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• v.30 no.1
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• pp.58-68
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• 2009

Three-dimensional distributions of longwave radiation flux for the April-September 1998 period are generated from radiative transfer calculations using the GEWEX Asian Monsoon Experiment (GAME) reanalysis temperature and humidity profiles and International Satellite Cloud Climatology Project (ISCCP) cloudiness as inputs to understand the effect of cloud radiative forcing in the monsoon season. By subtracting the heating of the clear atmosphere from the cloudy radiative heating, cloud-induced atmospheric radiative heating has been obtained. Emphasis is placed on the impact of horizontal gradients of the cloud-generated radiative heating on the Asian monsoon. Cloud-induced heating exhibits its maximum heating areas within the Indian Ocean and minimum heating over the Tibetan Plateau, which establishes the north-south oriented differential heating gradient. Considering that the differential heating is a ultimate source generating the atmospheric circulation, the cloud-induced heating gradient established between the Indian Ocean and the Plateau can enhance the strength of the north-south Hadley-type monsoon circulation. Cooling at cloud top and warming at cloud bottom, which are the vertical distributions of cloud-induced heating, can exert on the monsoon circulation by altering the atmospheric stability.