• Korean Journal of Materials Research
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• v.22 no.5
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• pp.259-273
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• 2012

Chalcogenide-based semiconductors, such as $CuInSe_2$, $CuGaSe_2$, Cu(In,Ga)$Se_2$ (CIGS), and CdTe have attracted considerable interest as efficient materials in thin film solar cells (TFSCs). Currently, CIGS and CdTe TFSCs have demonstrated the highest power conversion efficiency (PCE) of over 11% in module production. However, commercialized CIGS and CdTe TFSCs have some limitations due to the scarcity of In, Ga, and Te and the environmental issues associated with Cd and Se. Recently, kesterite CZTS, which is one of the In- and Ga- free absorber materials, has been attracted considerable attention as a new candidate for use as an absorber material in thin film solar cells. The CZTS-based absorber material has outstanding characteristics such as band gap energy of 1.0 eV to 1.5 eV, high absorption coefficient on the order of $10^4cm^{-1}$, and high theoretical conversion efficiency of 32.2% in thin film solar cells. Despite these promising characteristics, research into CZTS-based thin film solar cells is still incomprehensive and related reports are quite few compared to those for CIGS thin film solar cells, which show high efficiency of over 20%. The recent development of kesterite-based CZTS thin film solar cells is summarized in this work. The new challenges for enhanced performance in CZTS thin films are examined and prospective issues are addressed as well.

• Korean Journal of Environmental Agriculture
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• v.20 no.1
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• pp.50-56
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• 2001

Thirty-three bacterial and fungal strains were isolated from the rotten soybeans and soybean sprouts to isolate pathogenic microorganisms which cause soybean sprouts rot during soybean sprouts cultivation. In pathogenicity tests of the isolates on soybean sprouts, two isolates(K-17 and K-28) caused soybean sprouts rot and were identified as Erwinia carotovora and Fusarium sp., respectively. To isolate antagonists aganist K-17 and K-28 pathogens, bacteria were isolated from various soybean-cultivated soils and screened by the inhibition zone method. A bacterial isolate(J-232) which inhibited growth of both pathogens was identified as Pseudomonas fluorescens and further examined. The culture filtrate of P. fluorescens J-232 (dilution rate of 500 times) inhibited the growth of Erwinia carotovora K-17 and Fusarium sp. K-28 both on potato dextrose agar medium and on soybean sprouts cultivated in vessel. The development of soybean sprouts rots was observed during cultivation by inoculation of soybean seeds with culture filtrate of both pathogens. The combined inoculation of soybean seeds with culture filtrate of antagonistic bacterium and that of pathogens prevented soybean sprouts rot, and the growth of soybean sprouts was similar to that of control. The soybean sprouts inoculated with antagonists culture filtrate alone did not develop soybean sprouts rot, and the growth of the seedlings was shown to be slightly promoted as compared with that of control.

• Korean Journal of Environmental Agriculture
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• v.27 no.4
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• pp.464-473
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• 2008

Winter migratory birds gather in paddy rice fields to feed shed rice grains. The Korean Ministry of Environment has practiced a policy program Contract on Paddy Field Management (CPFM) during winter fallow since 2002. This program starts with a contract between local governments and farmers, and the government pays a differential subsidy to farmers who finish spreading rice straw, cultivating barley, letting the whole rice plant without harvest, and submerging paddy fields for winter migratory birds. As more local governments have operated CPFM program, the total area on the contract and subsidy budget has increased yearly since 2002. This program could have its stable position as a successful policy by giving profits to farmers. With the program extended, the population of winter migratory birds has been greatly. For the evaluation of environmental performance of a policy, we analyzed this CPFM program by introducing some indicators in the form of Driving Force-State-Response Framework. The indicators were composed of 3 categorized indicators; the area of paddy land contracted under this program as 'driving force' indicator, population of birds, the number of bird species and the amount of feces as 'state' indicators, and the size of monetary support, the number of farmers or local governments participating, and public perception as 'response' indicators. The contract area of paddy field under CPFM could be a good biodiversity indicator reflecting potential performance of this policy measure in the light of its linkage to the population of winter migratory birds. And the share of CPFM land of the whole agricultural land might also be used as a useful indicator of policy evaluation for improvement of wildlife diversity. The 'state' indicators such as population of birds and the number of bird species could be matched to 'driving force' indicator, but the total CPFM area of each site could not reflect the effect of areas under different management practices. However, the amount of bird feces could reflect differences in environmental performance with management practices as 'state' indicators. The development of indicators indicating 'response' such as farmers' behavior, public perception, and policy makers' willingness is also needed to support a successful implementation and improvement of this policy measure with the development of 'performance' indicators integrating all these indicators.

• Clinics in Shoulder and Elbow
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• v.16 no.2
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• pp.123-129
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• 2013

Purpose: The purpose of this study is to compare the clinical and radiological outcomes of two surgical treatments, transacromial pin fixation and hook plate fixation, for unstable distal clavicle fractures. Materials and Methods: Twenty four patients with Neer type II distal clavicle fractures who underwent surgery with transacromial pin fixation (Group I: 12 patients) and hook plate fixation (Group II: 12 patients) were included. Reduction and union were evaluated using plain radiographs. Functional evaluation was performed according to UCLA score and Constant-Murley score at last follow-up. Results: All 24 cases showed bone union. Complete union took an average of 10 weeks for group I and 11.7 weeks for group II. Average UCLA score was 33 (group I) and 32.8 (group II). Average Constant score was 88.5 (group I) and 88.8 (group II). No significant difference for each variable was observed between the two groups. Conclusion: For the surgical treatment of Neer type II distal clavicle fractures, transacromial pin fixation and hook plate fixation are both useful methods.

• Applied Microscopy
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• v.22 no.2
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• pp.15-29
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• 1992

The gallbladder is known to have the function of the storage and the concentration of the bile produced by the liver. This function is carried out by the removal of water and inorganic electrolytes. Extrahepatic cholestasis or the impairment of excretion of the bile leads to the distension and loss of the function of the gallbladder. The purpose of this study was to examine the ultrastructural characteristics of the normal gallbladder epithelial cells, and their structural changes induced by the ligation of common bile duct of the rabbit. Common bile duct ligation was performed under ether anesthesia. The rabbits were sacrificed on the 1st, 3rd, 5th, 7th and 14th day, respectively after operations. The tissue blocks of the gallbladder were fixed in 2.5% glutaraldehyde-1.5% paraformaldehyde prior to fixation in 1% osmium tetroxide, and embedded in the araldite mixture, and observed with JEM 100 CX-II electron microscope. The results were as follows: 1. The normal gallbladder epithelium of adult rabbit demonstrated two cell types, the ordinary epthelial cell and the dark cell. The dark cells have electron dense cytoplasm, and were found much infrequently, whereas ordinary epthelial cells were found quite numerous. 2. The ordinary epthelial cells of normal gallbladder were provided with the regular microvilli at the free surface and the images of pinocytotic activities in the apical cytoplasm, and exhibit highly convoluted lateral surfaces with elaborated microfolds. These figures of the cells suggest that they are resorptive in functional activity. 3. In the early stages (1st, 3rd, 5th day groups) following the ligation, the apical cytoplasm of some cells is protruding from the free surface and lost their microvilli. Numerous mucous granules filled in the apical and supranuclear cytoplasm compactly. 4. In the late stages (7th, 14th day groups) following the ligation, many light cells containing mumerous mucous granules are seen, between the ordinary epthelial cells. Mucous granules are fused each other, and are discharged into the lumen from the apical cytoplasm. The lateral membranes are straight or undulating without any interdigitations. From the above results, it was concluded that in the cholestasis induced by the common bile duct ligation, there is a tendency for the mucosal epithelium of the rabbit gallbladder to have secretory rather than an absorptive function.

• Journal of Life Science
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• v.21 no.7
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• pp.992-996
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• 2011

Endophytic fungi were isolated from the roots of plants growing naturally on the island of Dokdo. Plant samples, such as Miscanthus sinensis, Achyranthus japonica and Echinochloa crusgali were isolated from Dongdo, and those such as Honkenya peploides and Artemsia koidzumii were isolated from Seodo. Twenty one strains of endophytic fungi were isolated from these plants. To identify the strains, PCR (polymerase chain reaction) amplification of the partial ITS (Internal Transcribed Spacer) regions was done with universal primers ITS-1 and ITS-4 to determine the nucleotide sequence of the ITS regions. Of the strains isolated from Miscanthus sinensis, 75% were Penicillium sp. and 25% were Aspergillus sp. Fifty five percent of strains isolated from Achyranthus japonica were Penicillium sp., 30% were Aspergillus sp. and 15% were Zygorhynchus sp. Strains isolated from Echinochloa crusgali were Penicillium sp. (50%), Aspergillus sp. (12%), Giberella sp. (13%), Talaromyces sp. (9%) and Umbelopsis sp. (8%). Of the strains isolated from Honkenya peploides, 76% were Penicillium sp. and 24% were Pestalotiopsis sp. Strains isolated from Artemisia koidzumii were Penicillium sp. (81%) and Mucor sp. (19%). As a result of bioassay, Ec-3-1 strain isolated from Echinochloa crusgalli showed plant growth-promotion activity. Of all the endophytic fungi isolated, Penicillium sp. was the most abundantly distributed fungal strain in all plants used in this study.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.6
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• pp.573-581
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• 1987

The fish meat paste products are rapidly growing in its production. However, the recent prohibition of AF-2 gives a lot of difficulties in the marketing of fish meat paste products manufactured ty the conventional procedures. The present study aims to obtain the optimal conditions for retaining tile quality of the fish meat paste products with long shelf-life on the market. The fried fish meat paste was sealed in the retort pouches and sterilized under the conditions which the Fo value designated to 6. The effects of the sterilization temperature and the diameter of the products on the quality factors such as jelly strength, water holding capacity, texture and in vitro protein digestibility were investigated. The jelly strength and hardness increased as the sterilization temperature increased. On the other hand, there were no differences found in water holding capacity and elasticity. Of the samples, product with diameter of 12mm showed the highest values of jelly strength, hardness, L values and in vitro protein digestibility which sterilized at $124^{\circ}C$. However. tile results of the organoleptic tests showed rather score in the products with diameter of 16 mm than 12 mm which were sterilized at $124^{\circ}C $. From the results described above, it was concluded that the fried fish meat paste products with 16 mm or less in a diameter which were sterilized at higher temperature could keep high quality.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.3B
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• pp.421-430
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• 2010

Now a days, as a communications network is being broadband, IPTV(Internet Protocol Television) service which provides various two-way TV service is increasing. But as the data which is transmitted between IPTV set-top box and smart card is almost transmitted to set-top box, the illegal user who gets legal authority by approaching to the context of contents illegally using McComac Hack Attack is not prevented perfectly. In this paper, set-top box access security model is proposed which is for the protection from McComac Hack Attack that tries to get permission for access of IPTV service illegally making data line which is connected from smart card to set-top box by using same kind of other set-top box which illegal user uses. The proposed model reports the result of test which tests the user who wants to get permission illegally by registration the information of a condition of smart card which is usable in set-top box in certification server so that it prevents illegal user. Specially, the proposed model strengthen the security about set-top box by adapting public key which is used for establishing neighbor link and inter-certification process though secret value and random number which is created by Pseudo random function.

• Polymer(Korea)
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• v.30 no.2
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• pp.112-117
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• 2006

To improve the type error of osmotic tablet which is one of the drug delivery system, osmotic granule could be manufactured by fluidized bed coating. It has drug layer containing different amount of osmogant and is coated with membrane including different types of binder. We confirmed that the morphology of osmotic granule was different at each coating step. The more mont of osmotic agent, the faster drug release was observed due to increasing the driving force for drug release from osmotic granule. And drug release from osmotic granule coated with membrane using different types of binder was differed by solubility of binders to water. The formation of pore in membrane was confirmed by SEM and DSC Membrane using water soluble binder released more amount of drug. From these results, we assured that difference of osmotic pressure between the inside and the outside of granule and porosity of membrane have an effect on drug release from osmotic granule.

• Food Science and Preservation
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• v.22 no.3
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• pp.408-420
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• 2015

This study investigated the effect of heat treatment conditions on the quality and antioxidant activities of Korean traditional actinidia (Actinidia arguta) cultivars puree. Heat treatment on actinidia puree was conducted at $70{\sim}90^{\circ}C$ for 1 min to 5 mins, while a control sample of the actinidia puree was prepared without heat treatment. In all the samples, except for the sample treated at $90^{\circ}C$ for 5 mins, pH and Brix degree was not dramatically changed. Pulp content decreased with increasing temperature and time. L and the a value of color increased with increasing temperature and time. However, the b value showed a reverse tendency with L and the a value. Viscosity and gumminess increased as heat temperature and time increased, though cohesiveness was not significantly changed depending on temperature and time. Coliform and yeast were not detected on all samples and the number of aerobic bacteria and mold decreased as temperature and time increased. Vitamin C and total phenolic content of the puree was not changed for 1, 3, and 5 mins at $70^{\circ}C$ and for 1 and 3 mins at $80^{\circ}C$, but significantly decreased with increasing time at $90^{\circ}C$. Furthermore, the antioxidant activities of the puree, such as DPPH radical scavenging activity, ABTS radical scavenging activity, and FRAP (ferric reducing antioxidant power) showed a similar tendency with total phenolic content.