• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.235-240
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• 2005

Recently urban utility plants in urban areas of Korea, such as energy supply systems, municipal waste incineration systems, sewage treatment systems and so on, have caused some critical troubles, for instance the insensitive response to the seasonal or daily variation of loads, the low system efficiency and inefficient use of energy because of the large-scale system located a great distance. Therefor the design method of optimal integrated system model of various urban utility plants proposed in this study suitably to the present situation of Korea. Also, the effect analysis for the introduction of compound utility plants was studied for a new town model on a 60,000 persons scale. As the results we found that the complex plant was superior to individual urban utility plant in side of the initial investment expenses, the operating cost and other reasons.

• Plant Journal
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• v.6 no.1
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• pp.64-70
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• 2010

From 2000, the world plant market, especially plant developing business related to oil and gas, has been increasing. Domestic construction companies advance to overseas plant construction market actively, and proportioning to this, an importance of utility construction is increasing. However, the project becomes large and high-tech, and many companies experience difficulty of project management due to relatively high risk of overseas construction. In this study, we built the standard process with which domestic company can evaluate the risk of overseas plant utility construction. Primary factors for risk evaluation is derived, classification system is made out, primary factor is analyzed, and counter plan is suggested. And thorough management of risk is performed by risk management organization that manages the risks, risk control methods, reports and monitors through risk sheet and risk action log from the start of project to the end.

• Korean Chemical Engineering Research
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• v.46 no.1
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• pp.147-155
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• 2008

The economics of most chemical plants are heavily dependent upon the management of the utilities used in the plants. The utilities are supplied by the centralized utility system of the plant. Among the various utilities the steam is by far the most important energy source and the management of the electricity and the process water are greatly affected by the steam. Therefore it is necessary to educate students and new employees the basic concepts about the effective distribution of the utilities and the fundamental strategies to apply the concepts in actual plant operations. The OOUS (Optimal Operation of Utility System) is an GUI educational system designed to educate the effective generation of the steam and the optimal steam distribution schemes within short period. The OOUS deals with various utility equipments and processes and shows how to save operation costs by displaying the optimal operation conditions based on the process models and the operational knowledgebase.

• Korean Chemical Engineering Research
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• v.45 no.3
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• pp.234-241
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• 2007

To achieve safe operation and to improve economics it is imperative to monitor and analyse demand and supply of utilities and to meet utility needs in time. The main objective of motor/turbine processes is to manipulate steam and electricity balances in utility plants. The optimal operation of motor/turbine processes is by far the most important to improve economics in the utility plant. In order to analyse motor/turbine processes, we need steady state models for steam generation equipments and steam distribution devices as well as turbine generators. In addition heuristics concerning various operational situations are required. The motor/turbine optimal operation system is based on utility models and operational knowledgebase and provides optimal operating conditions when the amount of steam demand from various steam headers is changed frequently. The optimal operation system also produces optimal selection of driving devices for utility pumps to reduce operating cost.

• Journal of Plant Biology
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• v.22 no.3
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• pp.63-69
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• 1979

The plant growth and net production, the nitrogen uptake and recycling, the nitrogen mobility and allocation to each organ, and the nitrogen utility from the Italian rye grass field during the population development were analyzed in comparison with different clipping treatments. The maximum dry matter standing crop and nitrogen quantity of harvest increased significantly, however, the annual amounts of dry matter and nitrogen assimilation showed little variations with increasing clipping frequencies. Plants treated with frequent clippings allocated relatively more nitrogen to leaves and less to roots during the experimental period. The amount of recycling of nitrogen decreased considerably due to frequent clippings. The annual averages of nitrogen utility indices changed in inverse relation to the nitrogen availability; such as 63, 58, 44 and 35 for C, A, M and J plots, respectively.

• Plant Biotechnology Reports
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• v.5 no.1
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• pp.1-7
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• 2011

Secondary walls have recently drawn research interest as a primary source of sugars for liquid biofuel production. Secondary walls are composed of a complex mixture of the structural polymers cellulose, hemicellulose, and lignin. A matrix of hemicellulose and lignin surrounds the cellulose component of the plant's cell wall in order to protect the cell from enzymatic attacks. Such resistance, along with the variability seen in the proportions of the major components of the mixture, presents process design and operating challenges to the bioconversion of lignocellulosic biomass to fuel. Expanding bioenergy production to the commercial scale will require a significant improvement in the growth of feedstock as well as in its quality. Plant biotechnology offers an efficient means to create "targeted" changes in the chemical and physical properties of the resulting biomass through pathway-specific manipulation of metabolisms. The successful use of the genetic engineering approach largely depends on the development of two enabling tools: (1) the discovery of regulatory genes involved in key pathways that determine the quantity and quality of the biomass, and (2) utility promoters that can drive the expression of the introduced genes in a highly controlled manner spatially and/or temporally. In this review, we summarize the current understanding of the transcriptional regulatory network that controls secondary wall biosynthesis and discuss experimental approaches to developing-xylem-specific utility promoters.

• Advances in Traditional Medicine
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• v.9 no.3
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• pp.207-216
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• 2009

Bauhinia variegata Linn (Mountain Ebony) is a medium-sized, deciduous tree, found throughout India, ascending to an altitude of 1,300 m in the Himalayas. The plant is widely used by the tribals throughout India and popular in various indigenous systems of medicine like Ayurveda, Unani and Homoeopathy. Following the various traditional claims on utility of this plant in curing number of diseases, considerable efforts have been made by researchers to verify its utility through pharmacological screenings. The notable biological activities reported are anthelmintic, antiulcer, antitumour, antimicrobial, anti-inflammatory, antigoitrogenic, hepatoprotective and haemagglutination. Industrially, the plant is widely used for the manufacture of wood wool board, production of tannin, oil, gum and fibre. The plant is also utilized for afforestation to conserve the nature. In this article, a comprehensive account of the cultivation, microscopy, phytochemical investigation, traditional and biologically evaluated medicinal uses of B variegata is presented.

• 한국전산유체공학회:학술대회논문집
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• 2003.10a
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• pp.225-226
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• 2003

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2006.06a
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• pp.7.1-7.1
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• 2006

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.12 no.3
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• pp.132-138
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• 1998

The dynamic analysis of stability in industrial power system is an important subject. In this paper, the effect of voltage dips for short duration (short-circuit) in the utility system on generators, synchronous motors of the industrial plant and the measures to be adopted to reduce the undesired effects of voltage dips re investigated. In the case of utility three-phase short-circuits of longer duration, both the generators and synchronous motors in the plant may become unstable. In order to avoid instability through fault clearing in the second zone time a decoupling device is necessary. The instability of voltage can be avoided with a well suited setting time of disconnecting device and load trip.