• Current Research on Agriculture and Life Sciences
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• v.31 no.2
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• pp.101-107
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• 2013

This study was undertaken to determine free radical scavenging capacity and oxidative DNA damage protecting activity of methanol extract of red tea stem. The extract was subjected to assess their antioxidant potential using various in vitro systems such as $DPPH^{\bullet}$, $ABTS^{{\bullet}+}$, super oxide and nitric oxide free radicals and it exhibited $IC_{50}$ values of $68.88{\pm}1.1$, $12.08{\pm}0.65$, $404.38{\pm}1.6$, $93.6{\pm}2.7{\mu}g/mL$ respectively. Red tea extract also showed ferric reducing ability (FRAP) with 2606.85 mmol Fe (II)/g of extract. Furthermore, Methanol extract of red tea stem showed significant DNA damage protecting activity in concentration dependent manner against $H_2O_2+UV$ induced photolysis on pUC19 plasmid DNA. Results of this study showed that the methanol extract of Red Tea stem has strong antioxidant potential along oxidative DNA damage protecting capacity that would be the significant sources of natural antioxidants, which might be helpful in preventing the progress of various oxidative stress generated diseases. Further study is necessary for isolation and characterization of the active antioxidants, which may serve as a potential source of natural antioxidant.

• Smart Structures and Systems
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• v.3 no.3
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• pp.385-403
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• 2007

The effectiveness of the newly developed smart passive control system employing a magnetorheological (MR) damper and an electromagnetic induction (EMI) part for seismic protection of base isolated structures is numerically investigated. An EMI part in the system consists of a permanent magnet and a coil, which changes the kinetic energy of the deformation of an MR damper into the electric energy (i.e. the induced current) according to the Faraday's law of electromagnetic induction. In the smart passive control system, the damping characteristics of an MR damper are varied with the current input generated from an EMI part. Hence, it does not need any control system consisting of sensors, a controller and an external power source. This makes the system much simpler as well as more economic. To verify the efficacy of the smart passive control system, a series of numerical simulations are carried out by considering the benchmark base isolated structure control problems. The numerical simulation results show that the smart passive control system has the comparable control performance to the conventional MR damper-based semiactive control system. Therefore, the smart passive control system could be considered as one of the promising control devices for seismic protection of seismically excited base isolated structures.

• Applied Biological Chemistry
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• v.48 no.1
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• pp.48-52
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• 2005

Six stains of plant growth promoting rhizobacteria were selected through germinating seed assay and root colonization assay. Among them, SKU-78 strain induced significant suppression of bacterial wilt disease in tomato and pepper plants. Seed treatment followed by soil drench application with this strain resulted in over 60% reduction of bacterial wilt disease compared with the control. It was suggested that SKU-78 strain activated the host defense systems in plants, based on lack of direct antibiosis against pathogen. According to Bergey's Manual of Systemic Bacteriology and 16S rDNA sequence data, SKU-78 stain was identified as Bacillus sp. SKU-78.

• Journal of KIISE:Computer Systems and Theory
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• v.36 no.3
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• pp.181-190
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• 2009

Module is an object file that can be loaded into operating system dynamically and has complete privileged access to all resources in kernel. Therefore trivial misuses in a module may cause critical system halts or deadlock situations. In this paper, we propose Kernel Resource Protector(KRP) scheme to reduce the various problems caused by module. KRP provides protections of a variety of kernel resources such as memory, major number and work queue resource. We implement the scheme onto linux kernel 2.6.18, and experimental results show that our scheme can protect kernel resources effectively.

• The Journal of the Acoustical Society of Korea
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• v.20 no.4E
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• pp.3-16
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• 2001

An ASCII encoding of Korean has been developed for extended phonetic transcription of the Speech Assessment Methods Phonetic Alphabet (SAMPA). SAMPA is a machine-readable phonetic alphabet used for multilingual computing. It has been developed since 1987 and extended to more than twenty languages. The motivating factor for creating Korean SAMPA (K-SAMPA) is to label Korean speech for a multilingual corpus or to transcribe native language (Ll) interfered pronunciation of a second language learner for bilingual education. Korean SAMPA represents each Korean allophone with a particular SAMPA symbol. Sounds that closely resemble it are represented by the same symbol, regardless of the language they are uttered in. Each of its symbols represents a speech sound that is spectrally and temporally so distinct as to be perceptually different when the components are heard in isolation. Each type of sound has a separate IPA-like designation. Korean SAMPA is superior to other transcription systems with similar objectives. It describes better the cross-linguistic sound quality of Korean than the official Romanization system, proclaimed by the Korean government in July 2000, because it uses an internationally shared phonetic alphabet. It is also phonetically more accurate than the official Romanization in that it dispenses with orthographic adjustments. It is also more convenient for computing than the International Phonetic Alphabet (IPA) because it consists of the symbols on a standard keyboard. This paper demonstrates how the Korean SAMPA can express allophonic details and prosodic features by adopting the transcription conventions of the extended SAMPA (X-SAMPA) and the prosodic SAMPA(SAMPROSA).

• Journal of ILASS-Korea
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• v.18 no.4
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• pp.209-214
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• 2013

The present study aims to determine the optimized shape for the maximum electric energy production of building integrated photovoltaic system (BIPV) noise barrier through numerical analysis. The shape of BIPV noise barrier is one of the important factors in determining angle difference between direction vector of the sun and normal vector of the sound barrier surface. This study simulated numerically the flow and thermal fields for different angles in the range from $90^{\circ}$ to $180^{\circ}$, and from the results, the amount of isolation onto noise barrier surface was estimated along the angle between ground and top side of noise barrier. The commercial CFD code (Fluent V. 13.0) was used for calculation. It was found that the maximum amount of insolation per unit area was 19.6 MJ for $105^{\circ}$ case during a day in summer and was estimated 12.4 MJ in $150^{\circ}$ case during a day in winter. The results of the summer and winter cases showed the different tendency and this result would be useful in determining the appropriate shape of noise barrier which can be mounted under various circumstances.

• Journal of the Microelectronics and Packaging Society
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• v.11 no.2 s.31
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• pp.43-47
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• 2004

A coupler or divider is a microwave passive component used for power coupling or dividing. Regarding the trend of current telecommunication systems monolithic integration of passive components is highly desirable. In this study by the LTCC(Low temperature co-fired ceramics) technology a 2012 size type dual band coupler with multi-layer structure was fabricated. To achieve the desired coupling values for both DCS and EGSM bands, broad side coupled patterns were used with multi-layer structure. Its characteristics such as coupling, insertion loss, isolation and directivity values were measured and compared with simulation results.

• Journal of the Korean Home Economics Association
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• v.48 no.3
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• pp.99-114
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• 2010

This study explored the socialization of novice Home Economics(HE) teachers employing a qualitative research method. Data was collected through in-depth interviews with four novice HE teachers from secondary schools. The collected data was analyzed inductively by NVivo, a kind of CAQDAS. The following analysis was organized around three stages of teachers' careers: first, as for influences on teacher socialization prior to formal teacher education, their experiences on 'apprenticeship of observation' provided them both positive and negative role models; second, as for the socialization role of pre-service teacher education, they mentioned that college courses were poorly connected to classroom realities with only a few helpful lectures on HE Education; third, as for socialization in the workplace and its culture, the novice HE teachers were confronted with many kinds of problems including isolation in the classroom, in-service training programs not geared to novices, an overwhelming workload, and so on. Because of these problems, they yearned for and also formed networks with other HE teachers in order to overcome their limitations. The findings supported the notion that interactive and dialectical processes exist during all stages of HE teachers' careers. This study suggests that the teacher in-service training programs are more relevant, and that the introduction of mentoring programs and classroom manuals and teacher manuals would be helpful in practice. These innovations call for cooperation between universities and provincial offices of education for teachers' professional success in teacher socialization.

• Korean Journal of Construction Engineering and Management
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• v.14 no.1
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• pp.144-152
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• 2013

Design is an iterative, generative, and multidisciplinary process by its nature. Iteration occurs often in most of the engineering design and development projects including construction. Design iterations cause rework, and extra efforts are required to get the optimal sequence and to manage the projects. Contrary to simple design, isolation of the generative iterations in complex design systems is very difficult, but reduction in overall iterations is possible. Design depends upon the information flow within domain and also among various design disciplines and organizations. Therefore, it is suggested that managers should be aware about the crucial iterations causing rework and optimal sequence as well. In this way, managers can handle design parameters related to such iterations pro-actively. There are a number of techniques to reduce iterations for various kinds of engineering designs. In this paper, parameter based Design Structure Matrix (DSM) is chosen. To create this DSM, a survey was performed and then partitioned using a model. This paper provides an easy approach to those companies involved in or intend to be involved in "design and build projects".

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.5 s.248
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• pp.550-559
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• 2006

This paper presents designs and performance investigations of two bypass-type MR (magneto-rheological) shock dampers for high impulsive force systems, one of which is with single rod and the other with double rod. First of all, on the basis of the Bingham properties of the MR fluid and the magnetic field analysis of the magnetic circuit, the MR shock dampers are designed and manufactured. After experimental investigations on their magnetic field-dependent damping forces and responses characteristics, dynamic models of the proposed dampers are formulated and compared. Then, a simple 1 degree-of-freedom mass-drop system is constructed, and the effective and practical control algorithm is designed by considering dynamic characteristics of the shock control system. The shock control performances of the proposed MR shock dampers are verified through the comparison study of experiment results with simulation ones.