• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.90-94
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• 1984

We deduced a possible metabolic pathway of L-malate in a malo-alcoholic yeast, Schizosaccharomyces japonicus var. japonicus St-3. The malic enzyme (EC 1.1.1.40) prepared from the microorganism was about four times as active as that of malate dehydrogenase (EC 1.1.1.37). And Km values of malic enzyme and malate dehydrogenase for malate were found to be 3.125 mM and 4.761 mM, respectively, which referred to the fact that the affinity of malic enzyme for the substrate was greater than that of malate dehydrogenase. We also found that pyruvate was produced with disappearing malate in malo-alcoholic fermentation, and that the addition of $Mn^{2+}$ activated malic enzyme activity. Based on these results obtained we have deduced a main pathway of malate${\rightarrow}$pyruvate${\rightarrow}$acetaldehyde${\rightarrow}$ethanol for the utilization of L-malate by this malo-alcoholic yeast strain.

• Korean Journal of Optics and Photonics
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• v.13 no.6
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• pp.543-547
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• 2002

We have constructed two extended-cavity diode lasers which are phase-locked with a 9.2 GHz frequency offset. We adopted a digital servo circuit for the phase-locking. The relative linewidth of the phase-locked lasers was less than 2 Hz. Using the measured beat spectrum, we found the carrier concentration to be about 93 %. We measured phase noise and relative frequency stability of the lasers. The Allan deviation at the gate time of 20 s was $2.7{\times}10^{-19}$.

• Journal of Digital Convergence
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• v.11 no.7
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• pp.1-7
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• 2013

The reality which cannot protect existing tangible intangible modern cultural heritage in Daejeon is makes historical value and identity of a city weakened and then, this leads to absence of the foundation of urban regeneration based on the history. References as recording inheritance indicates characteristics or identity of the area and they represent the physical mental symbol of the area; images of diverse structures or sceneries with historical or cultural characteristics are contents of urban regeneration based on history and culture, which can be utilized as historical sources to verify realness of disappearing modern cultural heritage. Therefore, understanding and utilization of modern cultural heritage through this study on regional archiving can be deemed to be the first stage to bring community spirit, affection and pride to local residents. In this connection, this study intends to suggest a policy direction not only to maintain realness of modern cultural heritage through preservation and utilization but also to expect formation of settling and fellowship as well as cultural economical effect from the viewpoint of urban regeneration.

• Korean Journal of Clinical Pharmacy
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• v.8 no.1
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• pp.1-12
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• 1998

Rheumatoid arthritis (RA) is a common systemic inflammatory disease which DMARDS have been widely used as a treatment modality both as monotherapy and combination therapy Bucillamine, one of newer DMARDS, has recently proven its efficacy as monotherapy in the treatment of RA. The objective of this study was to compare the efficacy and the safety of bucillamine monotherapy and bucillamine plus methotrexate combination therapy in the treatment of rheumatoid arthritis. Forty-nine mild RA patients were enrolled in this prospective, open-trial and were assigned to receive bucillamine 200 mg/day (n=18) or bucillamine 200 mg/day and methotrexate 7.5-15 mg/week (n=31) orally for 16 weeks. Concomitant use of NSAID and prednisolone <5 mg/day or equivalent dose of steroid were allowed. Both monotherapy group and combination therapy group have shown significant improvement in disease activities (Ritchie index, painful joints, swollen joints, morning stiffness, grip strength, ESR, RF, CRP, patient's self assessment of pain, physician's global assessment of disease activity) from the baseline. However, there was no statistically significant difference between two groups. The adverse effects were more frequently shown in combination therapy group than monotherapy group. In conclusion, in patients with mild RA monotherapy has shown to be equally efficacious as combination therapy with less side effects.

• Journal of Korea Water Resources Association
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• v.36 no.3 s.134
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• pp.507-520
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• 2003

A V-shaped riffle is an artificial hydraulic structure haying two wings from the streamside with a narrow opening in between. It is usually made of crushed stones or large boulders. It limits channel width and accelerates the flow through the constricted section causing a local scour just downstream. The V-shaped riffle provides with a unique aquatic habitat by forming a pool and sandbars around the pool edge, increasing local morphologic, hydraulic and sedimentological diversity. This study investigates experimentally the scour characteristics of the V-shaped riffle in the sandbed stream and proposes a predictive equation for the scour. Total 45 cases of experiments were conducted to examine the effect of hydraulic factors and configuration of V-shaped riffle on the geometry of scour holes. From the comparison of the experimental results of this study with the predictive equation of spur dike by Breusers and Raudkivi(1991), it is found that their predictive equation of spur dike underestimates the maximum scour depth downstream of the V-shaped riffle. h new predictive equation for the maximum scour depth was developed using the non-dimensional hydraulic and geometrical variables. The parameters used in the proposed equations were determined using the experimental data. The analysis reveals that the scour depth is dependent dominantly on the Froude number at the opening of the V-shaped riffle, while the angle of riffle and the opening width also affect the scour depth. The proposed equation for the scour of V-shaped riffle well agrees with the experimental data. It can be used for estimating the scour of the V-shaped riffle in sandbed streams.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.8
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• pp.3421-3429
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• 2011

This is an exploratory study intended to clarify any mutually influential relationship among the political skills, social network and entrepreneurial performance of SMEs entrepreneurs who are known to have the most important influence upon the business performance. The results of this study show that as entrepreneur's social competence, political skills have significant influence on both social network and entrepreneurial performance, and that only some sub-factors of social network have significant influence on entrepreneurial performance. Especially, it was found that the source of weak ties mediates completely political skills and entrepreneurial performance. The above-mentioned results are meaningful in the light of considering any relationship between the capabilities and performance of SMEs entrepreneurs who have critical influence upon performance creation, and also clarifying concretely the bridging role of entrepreneur's social network between his/her social competence, or political skills and entrepreneurial performance. In addition, it is considered that this study has made a theoretical contribution in the light of introducing a concrete and new antecedent variable of political skills and establishing the role of social network, as well as a practical contribution in the light of presenting the real-world information on development of entrepreneur's competence which corresponds to a preparatory stage for performance creation.

• Journal of KIISE:Computer Systems and Theory
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• v.34 no.9
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• pp.459-466
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• 2007

TCP/IP processing imposes a heavy load on the host CPU when it is processed by the host CPU on a very high-speed network. Recently the TCP/IP Offload Engine (TOE), which processes TCP/IP on a network adapter instead of the host CPU, has become an attractive solution to reduce the load in the host CPU. There have been two approaches to implement TOE. One is the software TOE in which TCP/IP is processed by an embedded processor and the other is the hardware TOE in which TCP/IP is processed by a dedicated ASIC. The software TOE has poor performance and the hardware TOE is neither flexible nor expandable enough to add new features. In this paper we designed and implemented a hybrid TOE architecture, in which TCP/IP is processed by cooperation of hardware and software, based on an FPGA that has two embedded processor cores. The hybrid TOE can have high performance by processing time-critical operations such as making and processing data packets in hardware. The software based on the embedded Linux performs operations that are not time-critical such as connection establishment, flow control and congestions, thus the hybrid TOE can have enough flexibility and expandability. To improve the performance of the hybrid TOE, we developed a hardware-based transmission/reception accelerator that processes important operations such as creating data packets. In the experiments the hybrid TOE shows the minimum latency of about $19{\mu}s$. The CPU utilization of the hybrid TOE is below 6 % and the maximum bandwidth of the hybrid TOE is about 675 Mbps.

• Survey Research
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• v.10 no.3
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• pp.85-106
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• 2009

This study is an attempt to provide some answers to question about how characteristics and general recognition regarding internet use in Korea and Japan influence fostering and maintaining on-line social network in each of countries. Survey is used to compare Korean internet users and Japanese internet users in terms of characteristics of on-line social network, individual's propensity for internet use, including their recognition on internet. The study's main findings go as follows. First, Korean internet users tend to be more active in using internet than Japanese internet users do, thus having larger on-line social network and more intensive internet use than Japanese internet users do. However, there is a commonality that majority of internet users in both countries use internet to connect them to person with whom they have private relationship but they cannot meet frequently. Second, for Korean internet users, individual's propensity, characteristics, and recognition regarding internet use is not related to how to contact others. To the contrary, for Japanese internet users, how to contact others in on-line setting seems to vary according to whether or not they have relation-oriented internet use and how they recognize the availability of internet. Third, a commonality regarding the size of on-line social network is found between Korea and Japan that the total numbers of people enrolled as network increases if people use internet in order to get information. This confirms previous finding that relationship based on weak tie is instrumental in fostering on-line social relations and likely produces advantage in getting information. Finally, for Japanese internet users, the degree of risk recognized in on-line setting, that is the degree of interpersonal trust, appears to greatly influence overall relationship -building in on-line.

• The Journal of Society for e-Business Studies
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• v.24 no.4
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• pp.49-78
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• 2019

In the context of knowledge sharing, network position has been a controversial subject. A central position in the network provides access to non-redundant knowledge, leading to more opportunities of knowledge sharing. On the other hand, as "bridging" relationships, its characteristics as a "weak tie" suggest innate lack of trust and reciprocity which is considered an impediment to share knowledge. This paper attempts to enlighten the underlying dynamic by examining the interaction between network centrality, motivation and ability in knowledge sharing. Furthermore, this paper examines the concept of knowledge sharing ability in depth by operationalizing the construct into three aspects: extensive and diverse knowledge, social media utilization ability and self-efficacy. The results show a partially supported three-way interaction, where the highest level of knowledge provision is reported when the employee has low network centrality, high autonomous motivation and high knowledge sharing ability, i.e. extensive and diverse prior knowledge. Though all models indicate strong associations between network centrality and knowledge sharing, this suggests an even greater power of motivation and ability that gives the strength to overcome unfavorable environments of peripheral position. Therefore, this paper offers an alternative explanation to the existing debate whether network centrality positively or negatively influences knowledge sharing.

• Journal of Animal Science and Technology
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• v.44 no.6
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• pp.809-816
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• 2002

Chitosan is the deacetylated product of chitin. Chitosan and its derivatives have many properties that make them attractive for a wide variety of health applications. This study was conducted to investigate change of oligosaccharide content and antiviral effect on rotavirus of chitooligosaccharide and water soluble chitosan after heat treatment. The quantitative analysis of oligosaccharide using colorimetry showed that oligosaccharide contents in water soluble chitosan and chitooligosaccharide were decreased from 62.67% to 60.45% and from 59.48% to 54.31%, respectively, after heating. The inhibitory effect of chitosan derivatives on MA-104 cell infected with human rotavirus(HRV) measured using AEC staining method. The inhibition level of 0.125% water-soluble chitosan against cell infection by human rotavirus was 91.98 3.09% in HRV S2 and was 89.92 1.68% in HRV Wa. But, chitooligosaccharide had not shown inhibitory effect against cell infection by HRV. It considered that most oligosaccharide of chitooligosaccharides consist of oligomer of lower polymerization degree. Heat treatment of water soluble chitosan and chitooligosaccharide did not influence their antiviral effects on rotavirus.