• Journal of Animal Science and Technology
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• v.48 no.1
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• pp.91-100
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• 2006

In this study, changes of ammonia, alcohol and volatile fatty acid(VFA) concentrations or pH in in vitro ruminal fluid were studied to determine the effects of alcoholic feeds on in vitro ruminal fermentation characteristics. To formulate the alcoholic feeds, alcohol was added to commercial formulated feed at the levels of 1, 3, and 5 %. Experiments were done with four treatment groups, control(commercial feed), AF-1(commercial feed+1% alcohol), AF-3(commercial feed+3% alcohol), and AF-5(commercial feed+5% alcohol). Ammonia concentrations of AF-1 and AF-5 were significantly lower than that of control for the 12h incubation(p<0.05). Ruminal alcohol concentration was increased with the addition level of alcohol increased(p<0.05). TVFA concentrations of AF-1, AF-3 and AF-5 were significantly higher than those of control at 12h(p<0.05). Significant decrease of molar percentage of acetate was observed in control from 8 to 12h incubation, but molar percentage of acetate for AF-1, AF-3 and AF-5 was constant. Molar percentage of propionate was increased in control compared with AF-1, AF-3 and AF-5 from 8 to 12h incubation(p<0.05). Molar percentages of butyrate and valerate were higher in AF-1, AF-3 and AF-5 than in control(p<0.05). Molar percentage of caproate for AF-1, AF-3 and AF-5 was 0.05, 0.58 and 0.47M% at 8h, respectively, but that was not detected for control. Present results may indicate that the alcoholic feeds show positive effects on in vitro ruminal ammonia, alcohol and VFA concentrations or pH. Furthermore, the results of this study implies that the addition level of 5% could be more effective to ruminal fermentation than other addition levels.

• Asia pacific journal of information systems
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• v.22 no.3
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• pp.75-97
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• 2012

Knowledge residing in the heads of employees has always been regarded as one of the most critical resources within a firm. However, many tries to facilitate knowledge transfer among employees has been unsuccessful because of the motivational and cognitive problems between the knowledge source and the recipient. Social capital, which is defined as "the sum of the actual and potential resources embedded within, available through, derived from the network of relationships possessed by an individual or social unit [Nahapiet and Ghoshal, 1998]," is suggested to resolve these motivational and cognitive problems of knowledge transfer. In Social capital theory, there are two research streams. One insists that social capital strengthens group solidarity and brings up cooperative behaviors among group members, such as voluntary help to colleagues. Therefore, social capital can motivate an expert to transfer his/her knowledge to a colleague in need without any direct reward. The other stream insists that social capital provides an access to various resources that the owner of social capital doesn't possess directly. In knowledge transfer context, an employee with social capital can access and learn much knowledge from his/her colleagues. Therefore, social capital provides benefits to both the knowledge source and the recipient in different ways. However, prior research on knowledge transfer and social capital is mostly limited to either of the research stream of social capital and covered only the knowledge source's or the knowledge recipient's perspective. Social network theory which focuses on the structural dimension of social capital provides clear explanation about the in-depth mechanisms of social capital's two different benefits. 'Strong tie' builds up identification, trust, and emotional attachment between the knowledge source and the recipient; therefore, it motivates the knowledge source to transfer his/her knowledge to the recipient. On the other hand, 'weak tie' easily expands to 'diverse' knowledge sources because it does not take much effort to manage. Therefore, the real value of 'weak tie' comes from the 'diverse network structure,' not the 'weak tie' itself. It implies that the two different perspectives on strength of ties can co-exist. For example, an extroverted employee can manage many 'strong' ties with 'various' colleagues. In this regards, the individual-level structure of one's relationships as well as the dyadic-level relationship should be considered together to provide a holistic view of social capital. In addition, interaction effect between individual-level characteristics and dyadic-level characteristics can be examined, too. Based on these arguments, this study has following research questions. (1) How does the social capital of the knowledge source and the recipient influence knowledge transfer respectively? (2) How does the strength of ties between the knowledge source and the recipient influence knowledge transfer? (3) How does the social capital of the knowledge source and the recipient influence the effect of the strength of ties between the knowledge source and the recipient on knowledge transfer? Based on Social capital theory and Social network theory, a multi-level research model is developed to consider both the individual-level social capital of the knowledge source and the recipient and the dyadic-level strength of relationship between the knowledge source and the recipient. 'Cross-classified random effect model,' one of the multi-level analysis methods, is adopted to analyze the survey responses from 337 R&D employees. The results of analysis provide several findings. First, among three dimensions of the knowledge source's social capital, network centrality (i.e., structural dimension) shows the significant direct effect on knowledge transfer. On the other hand, the knowledge recipient's network centrality is not influential. Instead, it strengthens the influence of the strength of ties between the knowledge source and the recipient on knowledge transfer. It means that the knowledge source's network centrality does not directly increase knowledge transfer. Instead, by providing access to various knowledge sources, the network centrality provides only the context where the strong tie between the knowledge source and the recipient leads to effective knowledge transfer. In short, network centrality has indirect effect on knowledge transfer from the knowledge recipient's perspective, while it has direct effect from the knowledge source's perspective. This is the most important contribution of this research. In addition, contrary to the research hypothesis, company tenure of the knowledge recipient negatively influences knowledge transfer. It means that experienced employees do not look for new knowledge and stick to their own knowledge. This is also an interesting result. One of the possible reasons is the hierarchical culture of Korea, such as a fear of losing face in front of subordinates. In a research methodology perspective, multi-level analysis adopted in this study seems to be very promising in management research area which has a multi-level data structure, such as employee-team-department-company. In addition, social network analysis is also a promising research approach with an exploding availability of online social network data.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.5
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• pp.731-738
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• 2011

Cholesterol is the precursor of various steroid hormones, bile acid, and vitamin D with functions related to regulation of membrane permeability and fluidity. However, the presence of excess blood cholesterol may lead to arteriosclerosis and hypertension. Moreover, dietary cholesterol may affect blood cholesterol levels. Generally, cholesterol determination is performed by spectrophotometric or chromatographic methods, but these methods are very time consuming and costly, and require complicated pretreatment. Thus, the development of a rapid and simple analysis method for measuring cholesterol concentration in food is needed. Multi-walled carbon nanotube (MWCNT) was functionalized to MWCNT-$NH_2$ via MWCNT-COOH to have high sensitivity to $H_2O_2$. The fabricated MWCNT-$NH_2$ was attached to a glassy carbon electrode (GCE), after which Prussian blue (PB) was coated onto MWCNT-$NH_2$/GCE. MWCNT-$NH_2$/PB/GCE was used as a working electrode. An Ag/AgCl electrode and Pt wire were used as a reference electrode and counter electrode, respectively. The sensitivity of the modified working electrode was determined based on the amount of current according to the concentration of $H_2O_2$. The response increased with an increase of $H_2O_2$ concentration in the range of 0.5~500 ${\mu}M$ ($r^2$=0.96) with a detection limit of 0.1 ${\mu}M$. Cholesterol oxidase was immobilized to aminopropyl glass beads, CNBr-activated sepharose, Na-alginate, and toyopearl beads. The immobilized enzyme reactors with aminopropyl glass beads and CNBr-activated sepharose showed linearity in the range of 1~100 ${\mu}M$ cholesterol. Na-alginate and toyopearl beads showed linearity in the range of 5~50 and 1~50 ${\mu}M$ cholesterol, respectively. The detection limit of all immobilized enzyme reactors was 1 ${\mu}M$. These enzyme reactors showed high sensitivity; especially, the enzyme reactors with CNBr-activated sepharose and Na-alginate indicated high coupling efficiency and sensitivity. Therefore, both of the enzyme reactors are more suitable for a cholesterol biosensor system.

• Korean Journal of Agricultural Science
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• v.8 no.2
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• pp.238-243
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• 1981

This experiment was carried out to study the availability of Korean peat as a main carrier material of rhizobial inoculant, using the alfalfa strain Rhizobium meliloti M 14 which was isolated in the previous report. Modification of powdered peat with calcium carbonate and other materials was studied; inoculation of the peat with culture broth, maturation of the mixture under different conditions, and survival of the strain in the peat culture was examined. The results obtained were as follows. 1. Peat produced in Pyongtak was highly acidic, pH 3.8, and addition of calcium carbonate by 14% was required for pH adjustment to 6.4. However the amount of calcium carbonate could be reduced by 4 to 8% when carbon or charcoal was mixed with the peat. 2. Viable number of the strain reached to $7-9{\times}10^9cells/g$ after 3 days, when inoculated with the culture broth of early stationary growth phase and matured in unsteriled peat of open trays; and the number in steriled peat was $1.1-6.2{\times}10^{10}cells/g$ after 5 days, when matured in closed bottles. 3. Survival of the strain was affected markedly by storage temperature, and positive effect of D-sorbitol on the viability was recognized at elevated temperatures, when added as an additional carbon source and moistening agent. Glycerol, sorbitol, or sodium lactate was utilized by the strain as a sole source of carbon, and the decimal reduction time of viable number in the peat culture was was found to be 8 to 9 weeks at $25^{\circ}C$ when these agents were added by 0.5%.

• Management & Information Systems Review
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• v.39 no.2
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• pp.39-60
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• 2020

Block chain technology is one of the core elements for realizing the 4^th industrial revolution, and many efforts have been made by government and companies to provide services based on block chain technology. In this study we analyzed the benefits of block chain technology for EVMS and designed EVMS block chain platform with increased data security and work efficiency for project management data, which are important assets in monitoring progress, foreseeing future events, and managing post-completion. We did the case studies on the benefits of block chain technology and then conducted the survey study on security, reliability, and efficiency of block chain technology, targeting 18 block chain experts and project developers. And then, we interviewed EVMS system operator on the compatibility between block chain technology and EVM Systems. The result of the case studies showed that block chain technology can be applied to financial, logistic, medical, and public services to simplify the insurance claim process and to improve reliability by distributing transaction data storage and applying security·encryption features. Also, our research on the characteristics and necessity of block chain technology in EVMS revealed the improvability of security, reliability, and efficiency of management and distribution of EVMS data. Finally, we designed a network model, a block structure, and a consensus algorithm model and combined them to construct a conceptual block chain model for EVM system. This study has the following contribution. First, we reviewed that the block chain technology is suitable for application in the defense sector and proposed a conceptual model. Second, the effect that can be obtained by applying block chain technology to EVMS was derived, and the possibility of improving the existing business process was derived.

• Journal of the Korea Institute of Building Construction
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• v.18 no.2
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• pp.141-149
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• 2018

In this study, compacting, passing performance, segregation resistance and rheological properties were tested to improve the stability of fresh concrete in the production and construction of self-compacting concrete (SCC) using hollow glass powder(GB). As a result, T50 reaching time was shortened up to amount of GB $2.0kg/m^3$. The compacting according to the amount of GB was improved by ball bearing effect of GB. However, T50 reaching time was slightly increased at $4.0kg/m^3$. In the case of passing performance, the result showed that plain was Class 1, GB $0.5{\sim}2.0kg/m^3$ was Class 0, GB $4.0kg/m^3$ was Class 1. Therefore, the passing performance was improved with 'No blocking' up to amount of GB $2.0kg/m^3$. Passing performance Block step (PJ) number by J-ring method was also best at GB $1.0kg/m^3$. In the case of segregation resistance according to the amount of GB, dynamic segregation resistance was increased compared to plain regardless of the amount of GB. And static segregation resistance showed 2.5% of segregation rate at GB $1.0kg/m^3$. Therefore, it was greatly improved compared to plain (12.5%). In the case of rheology property according to the amount of GB, plastic consistency by increasing of GB content didn't show big difference. However, yield stress by increasing of GB content was decreased with GB $1.0kg/m^3$. In conclusion, GB $1.0kg/m^3$ was effective for improvement of compacting, passing performance and yield stress. Also, it will be useful for stability of SCC by improving segregation.

• Journal of the Korean Applied Science and Technology
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• v.32 no.2
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• pp.339-347
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• 2015

This study is to evaluate moisturizing effect and durability of UV A/B blocking activity with multiple (W/O/W) emulsion system. Most of the sun protective products come to be hot issue having both high SPF and long-lasting activity as using special products when is going out, mountain climbing and sports. Also, many consumers prefer the products which have the excellent waterproofing activity of sun care cosmetics as well as the non-sticky feeling that carried out the study of the sensorial science and texture preference. Therefore, development of the specific formulation using this multiple (W/O/W) emulsion technology, it has O/W type hydro skin feel having soft and moist texture when it is treated on the skin. Finally, this formulation is instantly changed to W/O type feel after adsorbed into the skin. The purpose of this study is to get high SPF lasting effect having high water resistance tactivity with high functional multiple (W/O/W) emulsion cream. We used major ingredients, UV-B absorbers were selected with ethylhexyl methoxycinnamate, isoamyl-p-methoxycinnamate, ethylhexylsalicylate, and octocrylene, UV-A absorbers were selected with butylmethoxydibenzoylmethane, bis-ethylhexyloxyphenol methoxy phenyltriazine. SPF effect of O/W type cream was 34.1. SPF effect of W/O/W type cream was 40.6 (increased about 19%). Water resistance effect after 4 hours, SPF effect of O/W type cream was 3.6 (quickly drop down). SPF effect of W/O/W type cream having 81.0 % waterproofing effect was 32.7 (decreased about SPF 7.9). Moisturizing effect of O/W cream at first was superior comparing multiple emulsion. But after 3 hours quickly was drop-down. Moisturizing effect of multiple emulsion was high comparing O/W type and other sun block creams after 4 hours was constantly maintaining water-content.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.1
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• pp.13-22
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• 1977

The following results were obtained in this work intended for getting more informations on features of phosphorus in Korean characteristic virgin, upland and paddy soils for knowing the ways how to evaluate the soil phosphorus availability and utilize fertilizers efficiently. 1. A large part of soil phosphorus is occupied by inorganic phosphorus in the soils of which the cultivated soils showed higher accumulation of applied phosphorus as inorganic forms than the uncultivated soils. The accumulation of organic phosphorus was indicated the highest in the paddy soils, and the lowest in the uncultivated soils. Than the cultuivated soil, the uncultivated soils have higher C/P ratio which was estimated to be related to soil fertility status essentially. 2. Iron phosphate was shown to be the most dominant form in soil phosphorus. Difference in parent rocks, from which the soils were originated, was shown to affect the carious distribution of phosphorus forms in the uncultivated soils to a large extent. The paddy soils have almost same distribution pattern of soil phosphorus forms regardless of different parent rocks. 3. The different methods for available phosphorus estimation extracted different amounts of phosphorus from the soils. Close relations between the available phosphours extracted with the different methods and the amounts of seil inorganic phosphorus were shown : e.g. between Fe-P and available-P by Olsen method. 4. Phosphorus absorption coefficient correlated negatively to soil inorganic phosphorus, and also to available phosphorus extracted with the several methods.

• Proceedings of the KSAR Conference
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• 2000.10a
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• pp.10-12
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• 2000

Members of the glycoprotein family, which includes CG, LH, FSH and TSH, comprise two noncovalently linked $\alpha$- and $\beta$-subunits. Equine chorionic gonadotropin (eCG), known as PMSG, has a number of interesting and unique characteristics since it appears to be a single molecule that possesses both LH- and FSH-like activities in other species than the horse. This dual activity of eCG in heterologous species is of fundamental interest to the study of the structure-function relationships of gonadotropins and their receptors. CG and LH $\beta$ genes are different in primates. In horse, however, a single gene encodes both eCG and eLH $\beta$-subunits. The subunit mRNA levels seem to be independently regulated and their imbalance may account for differences in the quantities of $\alpha$ - and $\beta$ -subunits in the placenta and pituitary. The dual activities of eCG could be separated by removal of the N-linked oligosaccharide on the $\alpha$-subunit Asn 56 or CTP-associated O-linked oligosaccharides. The tethered-eCG was. efficiently secreted and showed similar LH-like activity to the dimeric eCG. Interestingly, the FSH-like activity of the tethered-eCG was increased markedly in comparison with the native and wild type eCG. These results also suggest that this molecular can implay particular models of FSH-like activity not LH-like activity in the eCG/indicate that the constructs of tethered molecule will be useful in the study of mutants that affect subunit association and/or secretion. A single-chain analog can also be constructed to include additional hormone-specific bioactive generating potentially efficacious compounds that have only FSH-like activity. The LH/CG receptor (LH/CGR), a membrane glycoprotein that is present on testicular Leydig cells and ovarian theca, granulosa, luteal, and interstitial cells, plays a pivotal role in the regulation of gonadal development and function in males as well as in nonpregnant and pregnant females. The LH/CGR is a member of the family of G protein-coupled receptors and its structure is predicted to consist of a large extracellular domain connected to a bundle of seven membrane-spanning a-helices. The LH/CGR phosphorylation can be induced with a phorbol ester, but not with a calcium ionophore. The truncated form of LHR also was down-regulated normally in response to hCG stimulation. In contrast, the cell lines expressing LHR-t63I or LHR-628, the two phosphorylation-negative receptor mutant, showed a delay in the early phase of hCG-induced desensitization, a complete loss of PMA-induced desensitization, and an increase in the rate of hCG-induced receptor down-regulation. These results clearly show that residues 632-653 in the C-terminal tail of the LHR are involved in PMA-induced desensitization, hCG-induced desensitization, and hCG-induced down-regulation. Recently, constitutively activating mutations of the receptor have been identified that are associated with familial male-precocious puberty. Cells expressing LHR-D556Y bind hCG with normal affinity, exhibit a 25-fold increase in basal cAMP and respond to hCG with a normal increase in cAMP accumulation. This mutation enhances the internalization of the free and agonist-occupied receptors ~2- and ~17-fold, respectively. We conclude that the state of activation of the LHR can modulate its basal and/or agonist-stimulated internalization. Since the internalization of hCG is involved in the termination of hCG actions, we suggest that the lack of responsiveness detected in cells expressing LHR-L435R is due to the fast rate of internalization of the bound hCG. This statement is supported by the finding that hCG responsiveness is restored when the cells are lysed and signal transduction is measured in a subcellular fraction (membranes) that cannot internalize the bound hormone.

• Childhood Kidney Diseases
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• v.4 no.1
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• pp.40-47
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• 2000

Purpose: Renal involvement is the most important prognostic factor of HSP. Therefore, the pathogenesis and prognostic factors in renal involvement have been studied by many researchers. The aim of this study was to evaluate the clinical risk factors and the role of TNF-$\alpha$ in renal involvement of HS purpura. Methods: The subjects of this study were 12 patients of HS purpura, 7 patients of HS nephritis, and 5 age-matched controls. We have analysed the rist factors for renal involvement in clinical symptoms and collected the sera and urines of all subjects in acute and convalescent stage. The concentration of TNF-$\alpha$ in the collected sera and urines were measured by sandwich ELISA and compared with that of age-matched controls. Results: Statistical analysis showed that persistent purpura increased the risk of developing renal involvement (P=0.0018). and serum TNF-$\alpha$ levels in the acute stage of patients with renal involvement($11.45{\pm}7.01$ pg/ml) were significantly higher than those of without renal involvement($6.32{\pm}1.31$pg/m1) and of age-matched controls($5.99{\pm}1.34$pg/m1)(P=0.012, 0.027, respectively). However, urine TNF-$\alpha$ levels have no correlation with renal involvement. On investigation of serum TNF-$\alpha$ levels in acute stage of HS purpura, persistent purpura had a significantly higher increase(P=0.038). Conclusion: Serum concentration of TNF-$\alpha$ is a risk factor and has a predictable value along with clinical risk factors, such as, persistent purpura for renal involvement in HS purpura. Also, the effectiveness of the specific treatment fur antagonizing TNF-$\alpha$ in HS nephritis may need further study.