• Journal of Microbiology and Biotechnology
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• v.15 no.2
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• pp.296-301
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• 2005

The effect of aqueous methanol on the catalytic properties of porcine pancreatic lipase has been investigated. The k$_{CAT}$, values for the hydrolysis of N$^{alpha}$-benzyloxycarbonyl-L­lysine p-nitrophenyl ester at 0$^{circ}$C increased in a linear manner with increasing methanol concentration. However, the K$_{M}$ values were not influenced at methanol concentrations lower than $30\%$ and then began to increase at higher concentrations in an exponential fashion. Based on product analysis, the increase in k$_{CAT}$, with increasing methanol concentration can be accounted for by nucleophilic competition of methanol for the acyl enzyme intermediate, indicating that the rate-limiting step of the porcine pancreatic lipase-catalyzed reaction is deacylation under current experimental conditions. The exponential increase in K$_{M}$ at methanol concentrations higher than $30\%$ is attributed to the hydrophobic partitioning effect on substrate binding. There was no loss of lipase activity over a 4 h period in $60\%$ methanol concentration at pH$^{circ}$ 5.5 and 0$^{circ}$C. By monitoring the intrinsic fluorescence and absorbance, no evidence for structural changes by methanol was observed.

• Journal of Communications and Networks
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• v.17 no.3
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• pp.286-295
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• 2015

Avionic databuses fulfill a critical function in the connection and communication of aircraft components and functions such as flight-control, navigation, and monitoring. Ethernet-based avionic databuses have become the mainstream for large aircraft owning to their advantages of full-duplex communication with high bandwidth, low latency, low packet-loss, and low cost. As a new generation aviation network communication standard, avionics full-duplex switched ethernet (AFDX) adopted concepts from the telecom standard, asynchronous transfer mode (ATM). In this technology, the switches are the key devices influencing the overall performance. This paper reviews the avionic databus with emphasis on the switch architecture classifications. Based on a comparison, analysis, and discussion of the different switch architectures, we propose a new avionic switch design based on a time-division switch fabric for high flexibility and scalability. This also merges the design concept of space-partition switch fabric to achieve reliability and predictability. The new switch architecture, called space partitioned shared memory switch (SPSMS), isolates the memory space for each output port. This can reduce the competition for resources and avoid conflicts, decrease the packet forwarding latency through the switch, and reduce the packet loss rate. A simulation of the architecture with optimized network engineering tools (OPNET) confirms the efficiency and significant performance improvement over a classic shared memory switch, in terms of overall packet latency, queuing delay, and queue size.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.1B
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• pp.34-46
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• 2009

The remarkable growth of Korean telecommunication market has based on the introduction of competition as well as mobile technology like CDMA. It was well Down that such a conspicuous growth has been towed by mobile service rather than fixed telephone service. In telecommunications service the number of subscribers to mobile was over 40 millions in 2006 and also, while the traffic amount of fixed telephone has been more decreased, that of mobile, which already outnumbers the fixed, has been constantly increased and will be much more in future. It will accelerate the substitution of access and call demand of fixed service by mobile. This change of technology and demand does affect directly the market performance of telecommunications. And regulation has also an effect on market structure, which finally affects on market performance. In this paper we suppose the fixed and mobile telecommunications services are in a same industry. After reviewing the relations among the demand, cost, charge structure and revenue structure in the one fixed and mobile telecommunications market using the framework of an industrial structure analysis, we discuss the current issues of telecommunications regulation and implications for the future regulation.

• Journal of Korea Port Economic Association
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• v.22 no.1
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• pp.61-86
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• 2006

As the economic volume and trade in North-East Asia have dramatically increased, the competition for dominance over the value of logistics among many developed countries has taken a new turn. The Korean government has been planning a strategy for a north-east asian logistics hub in order to increase the global competitiveness of manufacturing companies by promoting a logistics industry. However, the competitiveness of Korean logistics industry is still quite premature compared to global competitors. Taking these accounts into considerations, this study advocates that the structure of Korean logistics companies should be changed from the function of furnishing simple logistics to extending integrated logistics services. It should also shift its focus from executing domestic logistics to meeting international logistics demands and from an execution-focused service to a knowledge-intensive service. The purpose of this study is to explore effective methods for stimulating an integrated logistics industry. Some detailed guidelines and economic interpretations, based upon the results of this research, have been suggested for supporting the related legislation.

• Journal of Plant Biology
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• v.14 no.3
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• pp.1-20
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• 1971

Ecological factors limiting Stipa pulchra have been determined in experimental gardens and at several sites in the hills south and east of Monterey, California. The Stipa pulchrafacies of Valley Grassland communities were found to be dominated by that species, though a total of 36 grasses and forbs were collected and identified. Basal area was not large, but aerial cover by Stipa alone averaged over 50 per cent. Across an ecotone between a Stipa association and the California Annual Type a sudden and dramatic change was recorded. Soil measurements there, and in other nearby areas, showed a much higher clay content with more available water and elemental phosphorus at the Stipa sites. Germination of Stipa seeds was high under all laboratory and field conditions, though growth of seeldings was highly variable. Seedlings grown in Stipa woil with an abundance of water were vigorous and reached anthesis the first year. In other soils they grew less, and when grown in competition with Avena fatua they scarcely grew at all. These findings indicate that when established on desirable soils, Stipa competes well and apparently precludes the dominance of Avena fatua and other large annual grasses. On the other hand, because of a lack of vigor in its seedlings, Stipa cannot reinvade the rich more friable soils on which it was once found, and on which it was shown to grow satisfactorily. This supports the contention that Sipa pulchra was the dominant grass through much of the Valley Grassland and Foothill Woodland, but also indicates that well-drained soils and those poor in mineral nutrients probalby never supported such associations.

• Journal of Wetlands Research
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• v.9 no.3
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• pp.63-74
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• 2007

In this Century, most of ports have been changing in order to keep up with change of the world. The ports are became larger and integrated with high technology because containers which pass through the ports are sharply increasing. Not to turn over the world wide competition of the ports, a renewal of Bukhang in Busan was promoted firstly in Korea. In this study, final draft renewal plan of Bukhang in Busan at this stage was compared with renewal plan of Haffencity in Germany in order to propose improved renewal plan of Bukhang in Busan. Renewal plan of Haffencity in Germany was very similar with Bukhang in Busan in terms of renewal period and direction. From the results of these comparisons, it was concluded that participation of private enterprise and international capital should be invested. Also, the facility plan of Bukhang was suggested to vitalize citizen's participation and embodimentof renewal plan. Prior to making a development plan enough consideration on the preservation of the environment is needed for the environmentally sound and sustainable development (ESSD). Also Korean tradition and culture should have to be considered in order to create the most Korean appearance.

• International Commerce and Information Review
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• v.6 no.2
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• pp.193-216
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• 2004

The management strategies of each company has been changed fundamentally owing to the emergence of digital economics by using internet. Therefore the efficient management of global e-port causes the main issues not only effect the survival and growth of ports but also exert new opportunities and fatal threats on them. Under the circumstances of these change, the Kwangyang port have to introduce e-biz for the purpose of increasing the level of their competition. The focus of this article is to suggest some strategies on the implementation of Kwangyang Global e-port in Korea. To analyse the e-port realities, I first reviewed the trends of e-marketing and e-biz. I chose and analysed website of four ports like Hongkong, Singapore, Antwerp and Hamburg as successful global e-port models. This article is focused to suggest the theoretical background by analysing the strategic points of Kwangyang global e-port which are divided in 6C: Contents, Communities, Connection, Commerce, Communication and Customization. This paper analyses many problems of Gwangyang port and presents various develpment ways to activate Gwangyang port. In order to be a global e-port, first of all Gwangyang port must improve global web-site by 6C. And also Gwangyang port have to constitute logistics hub site, create infrastructure needed to run electronic business more easily over the internet, establish nationwide network of industries, build up marine and port logistics information system.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.5
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• pp.302-307
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• 2004

As deregulation of power industry is becoming a reality, there has been an intense interest in the strategic bidding for suppliers to maximize their profits. The profit gained by a supplier is related not only to its energy-price bid curve but also to its submitted operational parameters such as generation capacity, etc. So suppliers are willing to use those strategic parameters that can be manipulated by themselves and are effective to their profit. This paper deals with the competition model with compound strategies: generation capacity and bidding curve. The parameter space is modeled by dividing into the two strategies, so the problem is made up of the four types of sub-game in a two player game. This paper analyzes the global Nash Equilibrium (NE) over the whole divisions by computing the sub-game NEs in some divisions and by deriving the best response curves which have discontinuities in other divisions. The global NE is shown to correspond to the Cournot NE where the quantity variable is realized by a constraints of a generation capacity.

• Journal of architectural history
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• v.29 no.2
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• pp.7-18
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• 2020

The purpose of this study is to examine the construction industry of Korea from the 1920s to the 1930s by analyzing activities of construction-contractors trying to overcome the recession of the construction industry and intensified competition in the industry. In this paper, I looked at the activities of Hanazono Sakichi as concrete examples. First of all, with the strategy of the vertical integration, by manufacturing and selling building materials, Hanazono Sakichi expanded his company and the scope of contract business. The second, he attempted to diversify related projects. Through related diversification, he seemed to have earned not only land management profit but also advantages from related construction. These aspects were not only seen by Hanazono's activities but also by other contractors'. On the other hand, a few contractors have taken over a trust company to secure the funds for land management. Attempts to maximize personal interests through the expansion and diversification of contractors' business can be seen as overcoming the pre-1920s environment, where almost construct works were ordered under the government, and creating opportunities for the private sector to work and make profit by themselves. In the end, it can be mentioned that 'the contractor' established 'the construction industry' through this process.

• Journal of the Korea Safety Management & Science
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• v.9 no.4
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• pp.99-112
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• 2007

In most recent years, the business competition has spreads over all fields of corporations and their management area regardless of time and place, which makes the survival environment of each enterprise fiercer. In order to secure a high position in the competitive market, the various firms has implemented many methods related to price, quality, and service efficiency. However, the implementation with only low price or high quality might be helpless to hold a high position in modem market. Moreover more attention should be paid to the internal business processes of an organization. Therefore, a new and different method should be searched or developed in order to win the competitive power among other enterprises. This research will focus on the improvement of the business processes within the non-manufacturing industry by applying Lean Six Sigma methodology. DMAIC method will be applied to improve the inbound and outbound logistics processes, manage the inbound and outbound vehicles, and control the receiving and shipping activities.