• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.399-404
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• 1975

In order to study on the utility for feed of several leguminosae tree leaves, the leaves of Lespedeza spp., Amorpha fruticosa and Robinia pseudo acacia were collected from several places of Daejon city and Daeduck-Kun at the different growing seasons. The leaf productivities, the change of the contents of chemical components on the different growing seasons. and the palatability trial were determined. The results were summarized as follows: 1. Leaf productivities of Amorpha fruticosa and Robinia pseudo acacia were higher than that of Lespedeza spp., and the highest production of Amorpha' fruticosa was showed in august and that of Robinia pseudo acacia was showed in september. 2. Crude protein contents of Lespedeza spp., Amorpha fruticosa and Robinia pseudo acacia were determined to 12.6, 18.63 and 15.87% respectively and the protein contents of them showed gradual decrease as growing. 3. Crude fat contents of Lespedeza spp., Amorpha fruticosa and Robinia pseudo acacia were determined to 9.00, 5.85 and 4.70% respectively, and they displayed gradual increase as growing, 4. Crude fiber contents of Lespedeza spp., Amorpha fruticosa and Robinia pseudo acacia were determined to 14.97, 12.61 and 9.80% respectively, and they showed gradual increase as growing. 5. The content of nitrogen free extract of Robinia pseudo acacia showed higher than those of Lespedeza spp. and Amorpha fruticosa, and all of them displayed gradual decrease as growing. 6. Crude ash contents of Lespedeza spp., Amorpha fruticosa and Robinia pseudo acacia determined to 4.40, 4.98 and 5.27% respectively, and variable changes were appeared as growing. 7. The results of palatability trial for three leaves showed superior to the order of Lespedeza spp., Robinia pseudo acacia and Amorpha fruticosa, and the dried leaves were more favorable than green leaves.

• Journal of fish pathology
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• v.20 no.1
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• pp.41-47
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• 2007

To investigate the cause of the mass mortality during rockbream, Oplegnathus fasciatus seed production, the water quality and bacterial counts of sea water in breeding tanks was measured 20days post the hatch. During breeding of rockbream fry, the environmental factors of water quality were detected as pH, ammonia COD, phosphate at the supply of the food organisms and the seawater. pH was decreased from the 8.21 of the 1 day per hatch (dph) to 7.56 of the on the 7 dph. Ammonia was conversely increased 0.49 ppm of the 1 dph to 0.85 ppm of 10 dph. As the adding of the chlorella and the rotifer tanks, COD was increased the 3.3 times and 1.2 times than those of pre-adding respectively. The phosphate and the ammonia were also increased 1.7 and 2.3 times, with adding the chlorella respectively, which exceeded the second grade for sea water evaluation level, 0.015 ppm and 0.1 ppm respectively. Water quality was not improved by PSB (Photosynthetic Bacteria) treatment, which increased the value of COD in 1.7 times, phosphate in 2.7 times and ammonia in 1.4 times. The number of the bacteria was also increased along the dph. According to the treatment of chlorella, the number of total bacteria increased in 1.4 times and those of Vibrio sp. 1.6 times. The lethal concentration of ammonia was investigated that over than 10 ppm could killed the fry of rockbream within 28 hrs, but 40% in 2 ppm.

• Journal of Ecology and Environment
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• v.29 no.3
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• pp.237-245
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• 2006

Changes of the biomass, net primary productivity and P/B ratio during abandoned field succession after shifting cultivation were investigated in Pyoungchang, Gangwon-Do, Korea. Aboveground standing biomass of herb species showed the maximum value (3.8 ton/ha) in the 5 year old-field, and decreased thereafter. Litter dry weight was depicted as a parabola form showing the gradual increment during the first 50 years and slight decrease thereafter. Basal area tended to increase logarithmically during abandoned field succession. Tree density showed the gradual increment during the first 15 years and decreased thereafter by the self-thinning process. In the later successional stage (80 years old-field), the shoot density distribution of the tree species by DBH class showed the reverse J shaped curve and Quercus mongolica dominated. Total standing biomass increased slowly in the earlier successional stages and later successional stages, and increased rapidly during the mid-successional stages ($10{\sim}50$ years old-field). Total standing biomass in the 5, 10, 20, 50 and 80 years old-fields were estimated 5, 14, 75, 251 and 373 ton/ha, respectively. Annual net primary productivity were depicted as a parabola form showing the gradual increment during the first 35 years and declined thereafter. The increment rates of the annual net primary productivity in the earlier successional stages showed the higher value than mid-successional stages. The annual net primary productivities in the 5, 10, 20, 35, 50 and 80 years old-field were estimated 8.6, 9.3, 12.9, 15.1, 13.7 and 3.6 ton/ha/yr, respectively. The estimated P/B ratio tended to decrease exponentially during abandoned field succession. The estimated P/B ratio in the 5, 10, 20, 50 and 80 years old-field were 0.60, 0.39, 0.19, 0.06 and 0.01, respectively. These results were fairly in accordance with the bioenergetics model during the forest succession projected by Odum(1969).

• Journal of Aquaculture
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• v.18 no.3
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• pp.147-153
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• 2005

The objective of this study is to elucidate the growth pattern of dark-banded rockfish, Sebastes inermis Cuvier, produced by aquaculture in Korea. Larvae from 250 maternal full-sibs were reared until 1,350 days after parturition. During the rearing period, growth equations on days after parturition (X) to the total length (TL) and body weight (BW) were estimated as TL=0.0217X $(r^2=0.8867)$ and $BW=0.0001X^2+0.0713X\;(r^2=0.9858)$, respectively. The relationship between BW and TL was $BW=0.0072TL^{3.4373}\;(r^2=0.9945)$. An increases in the eye diameter (ED) of dark-banded rockfish larvae on days after parturition (X) could be expressed as $ED=-2E-5X^2+0.0326X\;(r^2=0.9886)$. Relative growth equations on TL to head length (HL), snout length (SL), ED and postorbital head length (PHL) were calculated as $HL=0.2652TL\;(r^2=0.9758),\;SL=0.0613TL\;(r^2=0.9602),\;ED=0.0752TL\;(r^2=0.9715)$ and $PHL=0.2652TL\;(r^2=0.9501)$, respectively. Since there were few reports on the long-term growth experiment of this species due to difficulties in rearing techniques, results of this study would give a useful information to the biology and commercial culture techniques of dark-banded rockfish.

• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.423-429
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• 2008

Currently, Ash-free clean coal producing process by solvent extraction is under development. The produced ash-free clean coal can be directly combusted in a gas turbine which results in substantial improvement of power generation efficiency. However, the clean coal produced by the solvent extraction still contain trace amount of alkali metal which may cause corrosion on turbine blades during the direct combustion. In present work ${\alpha},{\beta}$-metal (Zr and Ti) phosphates and H-Y zeolite were synthesized and their ion exchange characterizations were investigated for the application on alkali metal removal for clean coal production. $Na^+$ ion removal capacities of the metal phosphates and H-Y zeolite were measured and compared in both aqueous solution (100 ppmw, $Na^+$) and coal dissolved N-methyl-2-pyrrolidone (NMP, 12 ppmw $Na^+$) at elevated temperature. In aqueous solution, the ${\beta}$ form metal phosphates showed very high ion exchange capacities compared to ${\alpha}$ form. ${\beta}$ form metal phosphates also showed higher $Na^+$ removal capacities than H-Y zeolite. In ion exchange medium of NMP, all the ${\alpha}$ form metal phosphates showed over 90% of $Na^+$ ion removal efficiency in the temperature range of 200 to 400 while that of H-Y zeolite decreased as a half when the temperature was over 350. In addition, the regenerated metal phosphates by acid treatment showed no sign of degradation in $Na^+$ removal efficiency. Among the metal phosphates used, $Zr_{0.75}Ti_{0.25}(HPO_4)_2$ showed the best performance in $Na^+$ removal and is expected to be the most suitable inorganic ion exchanger for the alkali metal removal process.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.7
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• pp.1017-1024
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• 2011

Korean wheat semolina (FS: fine semolina) with similar characteristics to durum wheat semolina was substituted at rates of 0, 10, 20, 30, 40, and 50% in pasta dough and the physical and cooking characteristics were investigated for making optimal pasta. Water absorption of the dough increased with the 10, 20, and 30% substitution ratio of FS. Development times were high with >30% substituted FS. This result positively influenced an increase in production and the preparation of the fresh noodle pasta. Furthermore, soft textured fresh noodles could be made due to the decrease in stability and increased weakness of the >30% substituted FS. The amylograph gelatinization characteristics of Korean wheat semolina exhibited an increase of gelatinization temperature and decrease of maximum viscosity when compared with durum wheat. The handling property of the dough showed more than 4 points in all sample groups. Weight and volume decreased and turbidity and cooking loss increased according to the increasing amount of substituted FS. However, samples with ${\leq}$ 30% FS substitution ratio had similar volumes and cooking losses when compared to the control. The L- and a-values increased and the b-value of color decreased as more FS was added. In a texture analysis, the hardness of the cooking noodles showed a low value with the >30% substituted FS. Springiness, gumminess, and chewiness exhibited a high value. In the results of a sensory evaluation, overall acceptability was high score with more than 7 points for the 30% added FS. The preferences for pasta colors were divided into white, which is similar to the Korean traditional noodle, and yellow, which is similar to durum wheat. Flavor and taste were not affected by substituting with FS. Low hardness and high chewiness was the most preferred noodle. These results suggest that >30% substituted FS was suitable for increasing quality and organoleptic qualities of Korean wheat pasta.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.375-375
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• 2010

CdTe as an absorber material is widely used in thin film solar cells with the heterostructure due to its almost ideal band gap energy of 1.45 eV, high photovoltaic conversion efficiency, low cost and stable performance. The deposition methods and preparation conditions for the fabrication of CdTe are very important for the achievement of high solar cell conversion efficiency. There are some rearranged reports about the deposition methods available for the preparation of CdTe thin films such as close spaced sublimation (CSS), physical vapor deposition (PVD), vacuum evaporation, vapor transport deposition (VTD), closed space vapor transport, electrodeposition, screen printing, spray pyrolysis, metalorganic chemical vapor deposition (MOCVD), and RF sputtering. The RF sputtering method for the preparation of CdTe thin films has important advantages in that the thin films can be prepared at low growth temperatures with large-area deposition suitable for mass-production. The authors reported that the optical and electrical properties of CdTe thin film were closely connected by the thickness-uniformity of the film in the previous study [1], which means that the better optical absorbance and the higher carrier concentration could be obtained in the better condition of thickness-uniformity for CdTe thin film. The thickness-uniformity could be controlled and improved by the some process parameters such as vacuum level and RF power in the sputtering process of CdTe thin films. However, there is a limitation to improve the thickness-uniformity only in the preparation process [1]. So it is necessary to introduce the external or additional method for improving the thickness-uniformity of CdTe thin film because the cell size of thin film solar cell will be enlarged. Therefore, the authors firstly applied the chemical mechanical polishing (CMP) process to improving the thickness-uniformity of CdTe thin films with a G&P POLI-450 CMP polisher [2]. CMP process is the most important process in semiconductor manufacturing processes in order to planarize the surface of the wafer even over 300 mm and to form the copper interconnects with damascene process. Some important CMP characteristics for CdTe were obtained including removal rate (RR), WIWNU%, RMS roughness, and peak-to-valley roughness [2]. With these important results, the CMP process for CdTe thin films was performed to improve the thickness-uniformity of the sputtering-deposited CdTe thin film which had the worst two thickness-uniformities of them. Some optical properties including optical transmittance and absorbance of the CdTe thin films were measured by using a UV-Visible spectrophotometer (Varian Techtron, Cary500scan) in the range of 400 - 800 nm. After CMP process, the thickness-uniformities became better than that of the best condition in the previous sputtering process of CdTe thin films. Consequently, the optical properties were directly affected by the thickness-uniformity of CdTe thin film. The absorbance of CdTe thin films was improved although the thickness of CdTe thin film was not changed.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.7 no.1
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• pp.5-22
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• 1994

This paper attempts to define some general characteristics of the Abstracting Journals published in Korea as evidenced in those published during last ten years. This purpose is achieved by comparing the results of the two studies conducted by the author in 1984 and in 1994. Both studies were conducted to present the state of the art in the abstracting services in Korea. The major conclusions made in this paper are summarised as follows： (1) Researchers and professionals working in a small number of subject fields are benefited by the abstracting journals, which provide current-awareness services of recent achievements in research and development in Korea. Those in most of the fields have no abstracting journals of their own, and naturally they have no substantial abstract-ing services. Even many researchers and professionals in the fields that have some abstracting journals are not informed of research results in their fields because the abstracting journals are scattered in many narrow subjects and in many cases, the abstracting journals only cover publications in some specific forms and kinds. (2) Abstracting journals that cover more than two subject fields, which are supposed to be of more or less help to the researchers and professionals in the subject fields that have no abstracting journals published in their fields, have rapidly increased in number in the past ten years. Most of suh abstracting journals carry thesis and dissertation abstracts, and the rest, those of research papers published in specific places, in specific forms, by specific institutions, and of reports of research projects sponsored by specific foundations. These abstracting journals are not of the kind that comprehensively provide researchers in related fields with current awareness of publications of research results in Korea. (3) Most of the abstracting Journals existing in Korea are Published by institutions of higher education and research institutes, and the rest, by commercial publishers, industrial firms, libraries, information centres, government agencies, research foundations, learned societies, etc. Those which publish many titles are small in number and those publish one or two titles are large in number. The former is largely made up of institutions of higher education and research institutes. (4) The abstracting journals published in Korea are classified by type into those of dissertations, research papers, journal articles, patent specifications in that descending order. The fact that Master; and doctoral dissertation abstracts ate dominating in Korea is due to the irrational practice of publishing those abstracts at many different institutions. (5) Most of the abstracting journals existing in Korea are published by national or government-supported research institutes in order to publicise their own research outputs. Their coverage of literature is normally narrow, and naturally their value to users is limited. (6) Korean is the desirable language for the abstracting journals intended to be distributed within Korea. About half of the abstracting jornals published in Korea is printed in Korean and the other half, in foreign languages, and in Korean and in foreign languages together. All the abstracting journals in foreign languages are printed in English except one, which is printed in Japanese. (7) Some twenty per cent of the abstracting journals in Korea is published monthly, bimonthly, and quarterly. The others are published annually, biannually and irregularly. The latter may not function properly as a current-awareness tool due to long intervals between their issues. It is particularly undesirable that about half of the abstracting journals in Korea is published irregularly. Most of the abstracting journals published in Korea are distributed freely to individuals and institutions selected by the publishers. (8) The abstracting journals published by the use of computers increased drastically in the past ten years. The abstracting journals produced by the conventional type-setting method will possibly disappear in Korea in another ten years to come. Automation of the production of abstracting journals does not simply mean technical, economic improvement in publishing processes but availability of machine-readable databases that can be used for many other pur-poses, including generation of other bibliographical publications and provision of machine literature searching capabilities. Necessary steps should be taken for this important development immediately.

• Journal of Bio-Environment Control
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• v.26 no.1
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• pp.43-48
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• 2017

This experiment was conducted to test the suitability of various organic materials in order to reduce the use dependence of peatmoss as a soil pH regulator and to examine the effect of soil organic matter supply. A 2-year old northern-highbush blueberry (Vaccinium corymbosum L.) 'Duke' plants were planted in the field at $2.0m{\times}2.5m$ spacing in spring. Before planting, organic materials were incorporated into the soil including the planting hole at 20 liter per plant, as the following mixtures: peatmoss only (20 L), peatmoss (10 L) + pine needle (10 L, PN), peatmoss (10 L) + rice hull (10 L, RH), and peatmoss (10 L) + sawdust (10 L, SD). The pH of organic materials was lowest in peatmoss (pH 4.3), followed by PN (pH 4.8), SD (pH 5.7) and RH (pH 7.8). Soil pH measured right after planting ranged from 5.3 to 5.9 and was lower in PM only and PM + PN than PM + RH and SD treatments. In the third year, the pH lowered to the range of 4.2 to 4.5, with PM and PM + PN still maintaining lower values. The early growth was good in the mixed treatment of PM and PN, and the plant height and width and the number of new shoots were good in the PM treatment. Soil water content was maintained highest in PM + PN, followed by PM, PM + SD and PM + RH. Vegetative growth was maintained better in PM and PM + PN, and the number of flower cluster and yield were also slightly higher in those treatments while mean fruit weight was similar among all treatments. Fruit quality indices such as total soluble solids, titratable acidity and firmness were not affected.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.5
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• pp.29-43
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• 2016

The Lean Startup, a methodology for minimizing failure rate of startups, has been receiving attention since its publication in 2011. Although it has been receiving enormous attention as an effective methodology of startups' growth and the emergence of unicorn companies, it is undeniable that the theoretical research and cases on this topic have not been fully accumulated in Korea. Progress of management theory has been made when combining the theory and case studies. In this paper, we thus excavated the 'Cardoc' case, which has applied the lean startup concept to the entire process of service and customer development from the inception of its product design. The following are the findings of the case. First, for the successful application of lean startup, it is essential that all team members to understand the lean startup concept and are willing to apply it thoroughly to the business management. Second, the prompt launching of MVP(Minimum Viable Product) is more important than table discussion. Third, it is crucial to select the appropriate key metrics and analytic tools for effective learning. Fourth, startup must scale up promptly as soon as it verifies the product-market fit through the BML(Build-Measure-Learn) iteration cycle. Fifth, all new business expansion should be lean. Cardoc is currently testing new MVPs in order to move onto the next scale-up process with huge investments in newly added segments. This study is meaningful in that it elaborates the representative case of a Korean startup that has applied the lean startup strategy under the circumstance of insufficient discussion of Korean startup cases in comparison with growing attention both in concept development and case accumulation abroad. We hope that this paper can be a stepping stone for future relevant research on the implementation of lean startup methodology in Korea.