• Journal of the Microelectronics and Packaging Society
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• v.21 no.3
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• pp.25-29
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• 2014

Plasma organic thin film for PCB surface finish is a potential replacement of the conventional PCB finishes because of environment-friendly process, high corrosion-resistance and long shelf life over 1 year. In this study, solder joint properties of the plasma organic surface finish were estimated and compared with OSP surface finish. The plasma surface finish was deposited by chemical vapor deposition from fluorine-based precursors. The thickness of the plasma organic coating was 20 nm. Sn-3.0Ag-0.5Cu (SAC305) solder was used as solder joint materials. From a salt spray test, the plasma organic coating had higher corrosion resistance than the OSP surface finish. The spreadability of SAC305 on plasma organic coating was higher than that on OSP surface finish. SEM and TEM micrographs showed that the interfacial microstructure of the plasma surface finish sample were similar to that of the OSP sample. Solder joint strength of the plasma finish sample was also similar to that of the OSP finished sample.

• Progress in Medical Physics
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• v.16 no.3
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• pp.148-154
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• 2005

Since the output of retina for visual stimulus is carried by neurons of very diverse functional properties, it is not adequate to use conventional single electrode for recording the retinal action potential. For this purpose, we used newly developed multichannel recording system for monitoring the simultaneous electrical activities of many neurons in a functioning piece of retina. Retinal action potentials are recorded with an extra-cellular planar array of 60 microelectrodes. In studying the collective activity of the ganglion cell population it is essential to recognize basic functional distinctions between individual neurons. Therefore, it is necessary to detect and to classify the action potential of each ganglion cell out of mixed signal. We programmed M-files with MATLAB for this sorting process. This processing is mandatory for further analysis, e.g. poststimulus time histogram (PSTH), auto-correlogram, and cross-correlogram. We established MATLAB based protocol for waveform classification and verified that this approach was effective as an initial spike sorting method.

• Journal of Mushroom
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• v.18 no.3
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• pp.260-267
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• 2020

Phellinus baumii, a white-rot fungus, has been used for centuries as folk medicine in China, Japan, and Korea. This study aimed to evaluate the in vitro anti-diabetic, and anti-cholinesterase, and in vivo anti-inflammatory effects of the fruiting bodies of P. baumii. The methanol (ME) and hot water (HE) extracts (2.0 mg/mL) of P. baumii fruiting bodies suppressed α-amylase activity, exactly 61.33%, and 65.00%, respectively; of note, acarbose, the positive control, inhibited 93.33% of the α-amylase activity. Moreover, the ME and HE (2.0 mg/mL) inhibited 89.67% and 91.00%, respectively, of the activity of α-glucosidase activity, whereas the same concentration of acarbose suppressed 84.67% of the α-glucosidase activity. The ME and HE (1.0 mg/mL) also inhibited 96.05% and 94.58%, respectively, of the acetylcholinesterase (AChE) activity; galanthamine, the positive control, led to an inhibition of 81.12%. The butyrylcholinesterase (BChE) activity was also inhibited by ME and HE (1.0 mg/mL; 91.05% and 82.27%, respectively); of note, the same concentration of galanthamine suppressed 81.12% of the BChE activity. The production of NO in LPS-induced RAW 264.7 macrophages was significantly suppressed by both ME and HE treatments. Importantly, the carrageenan-activated rat hind-paw edema was significantly reduced 2-6 h after ME administration (50 mg/mL). Taken together, the results suggest that the fruiting bodies of P. baumii have α-amylase, α-glucosidase, α-cholinesterase, and anti-inflammatory activities, and, therefore, may be good natural sources for the promotion of human health.

• Analytical Science and Technology
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• v.13 no.2
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• pp.166-172
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• 2000

The life expectation of power transformers is basically dependent on the aging deterioration of insulating paper which can not be obtained from operating transformers. Therefore, it will be very useful if we can manage transformers by indirect analysis of degradation products. "Furan derivatives" are known the decomposition products which are generated by the degradation of cellulose in insulating paper. We proved that 2-furfural is the only measurable product from our transformers, and determined easily the concentration of 2-furfural by HPLC without any specific pretreatments, Compared to concentration of $CO_2$ and CO by GC, the concentration of 2-furfural by HPLC can estimate more accurately aging characteristics of transformers. We expect that these results can be utilized to predict the aging characteristics and life diagnosis of power transformers.

• Journal of Korean Society of Forest Science
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• v.80 no.1
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• pp.1-8
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• 1991

Developmental micropropagation method and somatic embryogenesis for hybrid poplars, Populns ehrarnericana Eco28, P. nigra ${\times}$ P. moximowiczii 62-9, were established using nodule culture system. Calli of Eco28 and 62-9 clone were initiated from leaf explant on the medium with 0.5mg/l and 2.0mg/l 2, 4-D, respectively. Cell suspension culture was established from callus derived from leaf explant culture. When suspended on MS medium with optimal combination of BA and NAA fine nodules were obtained after 2 weeks of culture. For shoot regeneration, nodules were transferred into liquid and agar solidified medium. Numerous shoots were regenerated from nodules of 62-9 on liquid media. Organogenesis was effectively achieved on agar solidified regeneration media containing different concentrations of BA and adenine sulfate. Average numbers of 27 and 24 shoots per nodule were induced from 62-1 and Eco28 clones after 8 weeks of culture, respectively. In addition, somatic embryogenesis also occurred in the same regeneration medium. This procedure can be applied to vegetative propagation, utilization of somaclonal variation, production of secondary metabolite and materials of biotechnology research.

• Korean Journal of Ichthyology
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• v.25 no.2
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• pp.106-118
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• 2013

Monthly variation in species composition of shallow water fish in Cheonsu Bay were determined using samples collected by a beach seine in the shallow water at Namdang beach from April 2010 to March 2011. The species composition were compared to the data obtained in 1885~86 and in 1993, and factors affecting the long-term change in species composition were analyzed. Fish collected during the study were 25 species, 2,194 individuals and 16,762 g. Chelon haematocheilus were predominated in abundance, accounting 68.5% in the number of individuals. A few number of fish were collected during the cold months from November to April. Abundance was high from July to September by a large catch of juveniles of pelagic fish. Species composition in 1993 did not differ significantly from that in 1985~86 although Fabonigobius gymnauchen living in the fine sediments were increased in abundance. Abundance increase of this gobiid fish was considered to be related to the sedimentation of fine particles due to weakened water circulation after dike construction. The number of species and catch amount in 2010~11 were significantly decreased comparing to those of the former periods; especially in pelagic fish and benthic fish, but C. haematocheilus were greatly increased in abundance. C. haematocheilus is an estuarine fish being able to survive in relatively poor quality of water. This increase seems to be related to fish larvae from the culture net cages recently installed in the inner bay. Recent decrease in abundance of shallow water fish suggested that water quality has been gradually getting poor and recently attained over a critical level for the nursery function of fish.

• Geophysics and Geophysical Exploration
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• v.13 no.4
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• pp.407-415
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• 2010

MT soundings were carried out in 2008, in northern Victoria, Australia, as a continuing collaboration research of 2007 between Republic of Korea, Australia, and Japan. The main purpose of this research is to investigate electrical conductivity structure and thus help understanding of tectonic structure in central Victoria, which is believed to be closely linked to mineralization and magmatic processes of this region. The survey area is located in western Lachlan Fold Belts, which is the part of Tasman Fold Belts in southeastern Australia. An MT profile of 2008 is almost parallel to the one of 2007 and approximately 50 km away. The 2D inversion result of MT data also shows that the position of conductivity discontinuity near surface are well matched with the positions of major faults, such as Avoca Fault, which is the structural boundary between Stawell and Bendigo Zones, and Heathcote Fault Zone, which marks the boundary between Bendigo and Melbourne Zones. It is also confirmed from resistivity image that internal faults in Bendigo Zone are in listric form, which is implied to be formed by structural shortening during compressional orogenic activity in Silurian.

• Culinary science and hospitality research
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• v.6 no.1
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• pp.57-78
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• 2000

In the 21st century the size of sales of food service business in Korea will be 30 trillion won which means Food service business in Koreas is a mega market, but it is only quantitative growth and might face the limit of growth. At the same time it is predicted that from the academic world Food service business will develop endlessly after IMF condition. Of course I hope so as a member of national. Al though I propose that quantitative side is important, qualitative side must not be disregarded the present and future customer is needs should be met because the 1st goal of company is to achieve a management goal and pursuit profit. The present situation requires a peculiar and specific strategy of its own which can not be followed by competing hotels so that value can be created and buying intention can be occurred after buying. Until now the goal of marketing campaign has been transacted marketing just for closing a transaction, but it must be related marketing which is seeking mutual interests of customer and company. The strategies to attain these goals are : 1) to change from products and service management-focused to customer management and relationship building-focused. 2) to establish a core strategy which needs to be changed from market occupancy of volume expansion to customer occupancy. 3) to change from one-way communication to two-way communication. 4) to change from large scale marketing by company dimension to small scale marketing by sections. If companies focus on core benefit and augmented service to be sought by customers and make every efforts to create a value customer occupancy will increase automatically, the reduction of marketing cost will be followed, and marketing efforts will be much more efficient. In introducing a new product it is still easier to diffuse through the existing customers, and also important market information can be obtained from customers using this close relationship. If this close relationship maintains well customers will say even a trivial inconvenience and complaint and propose an idea of new product. Kotler divides relationship marketing into 5 stages such as Basic, Reactive, Accountable, Proactive, and Partnership. From the 1st stage to the last stage customer management is absolutely important and also in management strategy. The last stage, Partnership can come into the stage which is actively participated in service development and problem solving by customers. so more loyal customers have more successful performance the company attain.

• Geophysics and Geophysical Exploration
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• v.18 no.4
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• pp.171-180
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• 2015

Electrical resistivity of 23 core samples from Ulleung Island at dry or saturated condition has been measured along with dry density and effective porosity, and the relations between the properties has also been discussed. Upper and lower bounds of electrical resistivity at room temperature can be provided by the dry- and saturated-resistivity, respectively. Injecting nitrogen gas to the pore space at the very end of drying process can prevent humid air from getting into the pore space, so that measurement of dry-resistivity can be less affected by humidity in the air. Dry density and porosity have very close correlation; the ratio between increase of porosity and the decrease of density showed distinct relation to the rock types, such that basaltic rocks showed higher ratio while trachytic rocks showed lower. Saturated resistivity showed close correlation to density and effective porosity of the rock sample, while dry resistivity didn't.

• Journal of Conservation Science
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• v.7 no.2
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• pp.80-85
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• 1998

The structure, dimensions, condition and other characteristics of the Koryo Buddhist Canon (the Koreana Tripitaka) Printing Wood Blocks stored at the Haein-sa Monastery were surveyed to obtain basic data needed for the conservation of the Wood Blocks. The dimensions of the Wood Blocks Were measured and we could figured out the blueprint designed at the time of the carving the Wood Blocks. The dimensions of the wooden board were as follows: width, 8'chi'('cun' in Chinese, 24 cm);thickness, 1 'chi' (3 cm); length, 2'cha' ('chi' in Chinese) and 3 'chi' (68 cm) or 2 'cha' and 6 'chi' (78 cm). The dimensions of the end pieces were as follows: width, 1 'chi' and 5 'fun' (4.5 cm; thickness, 1 'chi' and 4 'fun' (4 cm); length, 8 'chi' and 2-4 'fun' (24.6-25.2 cm). There were 6 types of metal strips and the length of the nails employed was 1 'chl' (3 cm). Investigation on the differences in the length of the wood Blocks and the shapes of the metal strips will be of interest. Since we surveyed only small portion of the Wood Blocks. the result may be different if entire Wood Blocks were examined. The data acquisition of the entire Wood Blocks will be the basis to the conservation of the Wood Blocks.