• Korean Journal of Pharmacognosy
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• v.39 no.3
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• pp.213-217
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• 2008

Oxidative stress is considered to play an important role in a variety of neurodegenerative disorders of central nervous system. The immortalized mouse hippocampal cell line, HT22, phenotypically resembles neuronal precursor cells but lacks functional ionotropic glutamate receptors, thus excluding excitotoxicity as a cause for glutamate triggered cell death. Therefore, HT22 cells are a useful model for studying oxidative glutamate toxicity. In this study, we examined whether the methanol extracts of some native plants at Mt. Baekdu could protect HT22-immortalized hippocampal cells against glutamate-induced oxidative stress. Seventy-eight plants sources were collected at Mt. Baekdu, and extracted with methanol. These extracts had been screened the protective effects against glutamate-induced oxidative damage in HT22 cells at the 100 and 300 ${\mu}g/ml$. Of these, thirteen methanolic extracts, Acer mono (leaf), Artemisia stolonifera (aerial part), Carduus crispus (aerial part), Carex mongolica (whole plant), Clematis hexapetala (whole plant), Galeopsis bifida (aerial part), Galium verum (whole plant), Ganoderma lucidum (whole plant), Ixeris chinensis (whole plant), Malva verticillata (aerial part), Polygonum senticosum (whole plant), Rebes mandshricum (branch), and Taraxacum mongolicum (aerial part), showed significant protective effects against glutamate-induced oxidative damage in HT22 cells.

• Journal of fish pathology
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• v.22 no.3
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• pp.239-251
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• 2009

The effects of microbiological properties and pathogenicity of Photobacterium damselae subsp. damselae were investigated under different culture conditions, temperature, pH, NaCl and iron concentration on culture media. Favorable conditions for bacterial growth were between 15-30${^{\circ}C}$, pH 5-9, 0-4% NaCl concentration and iron contents of over 10 mM, whereas the bacterial growth was inhibited under iron chelator existence. When P. damselae was cultured in iron-limited tryptic soy broth, total protein concentration of extracellular products, cytotoxic ability of ECPs on cell line, bacterial viability in flounder serum, phospholipase and siderophore activities of ECPs were significantly increased. On the other hand, the activities of P. damselae cultured under iron-added conditions were decreased. In this study, the iron-limited conditions were similar to the host in which iron concentration is low. During infection caused by P. damselae, the conditions could be related to the pathogenesis of the pathogen.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.4A
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• pp.377-384
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• 2006

According to fast VoIP technology development, more and more companies change voice network into IP based network among branch offices. IP PBX, which is deployed up to now, composed of IP phone and VoIP Gateway. Every telphone has replaced with If phone which support VoIP and VoIP gateway is installed in PBTN connection point to relay voice data. It can reduce the communication expense of International call, long distance call and call between a headquater and a trance because it uses internet line. In this paper, IP PBX is implemented that can distribute call using PBX network only usig personal terminal without Proxy Server. Depending on Role, terminal can be registered Master, Server and Client and it is verified in terms of performance and validation.

• Journal of the Korean Chemical Society
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• v.39 no.1
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• pp.40-46
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• 1995

A new analytical luminescence method for the Tb+3 and Eu+3 ions was studied using the fluorescence enhancement of the ions on the TLC plate. Compared to the specific emission intensities of the ions in aqueous or ethanol solution, if spotted on the TLC plate, the line intensities were extremely enhanced. There was additional enhancement effect of the lines from the ions on the TLC plate, if treated with ο-phenanthroline. Based on the luminescence enhancement, the detection limit of the ions was lowered more than 6 order of magnitude compared to the luminescence method using solution samples. The energy-transfer mechanism was also explained for the theoretical back ground of the luminescence enhancement.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.5
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• pp.611-620
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• 2011

A planar monopole antenna that was developed for WLAN/WiMAX application is presented in this paper. The proposed antenna with three strips, an asymmetrical ground plane, and a rectangular slit in the ground is designed to cover the popular frequency spectrum of WLAN (wireless local area network) bands and WiMAX (Worldwide Interoperability for Microwave Access) bands. The proposed antenna, which is capable of wideband operation, is fed by a strip line and fabricated on an FR-4 substrate. The obtained numerical results agree well with the experiment data. It was validated that the configuration can meet the demands for the WLAN/WiMAX systems and effectively enhanced the impedance bandwidth to 9.95% for the lower band and 76.05% for the upper band for VSWR < 1 : 2. This paper also presents and discusses the 2D radiation patterns and 3D gains according to the results of the experiment.

• Journal of the Korean Society of Safety
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• v.27 no.3
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• pp.153-160
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• 2012

Various social problems such as traffic congestion, car accidents and environmental problems(air pollution, noises etc.) have been happening in the Seoul metropolitan area that has the car oriented traffic system providing cars continuously. Along with this, the financial burden caused by current oil price anxiety made paradigm shift from caroriented to public transportation-oriented. Its typical example is an arterial branch bus system changing(bus lane through the center of main road) started in Seoul in July, 2004. But study on safety analysis of bus lane and characteristic of accidents are not sufficient enough to now. The bus lanes are expanded to provide roads for better traffic operation and accidents between buses and pedestrians or ordinary vehicles are considered main problems. This study divided each bus route of median bus lane(bus-only lane through the center of main roads) and bus lane at roadside by intersection and collected and analysed data about influence variables of bus accidents chosen in each section. We constructed a logistic model using collected data. As a result, bus lane at roadside are used by both buses and other kinds of vehicles differently from median bus lane and showed such characteristic in accident influence. Therefore access management to factors causing conflict and improvement of operation management are required. In case of median bus lane, the more buses moving general vehicle lane and traffic volume of section were, the more accidents happened. In case that stop line of center lane is not backward, view blocking of vehicles turning left caused accidents.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.05a
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• pp.638-642
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• 2002

User in video data utilization of high-capacity can grasp whole video data at a look. Offer frame list that summarize information of video data to do so that can remake video from branch that want when need. Need index process of video data for effective video retrieval. This treatise wishes to propose effective method about scene change point detection of video that is been based on contents base index. Proposed method video data so that can grasp whole structure of video detection color value of schedule pixel for diagonal line direction in image sampling do. Data that get into sampling could grasp scene change point on one eye. Color value of pixel that detection in each frame is i frame number by i$\times$j procession to procession A, j stores to reflex height of frame. Introduce MSE and calculate mean error of each frame. If exceed mean error and schedule critical value, wish to detect the frame for scene change point.

• Korean Journal of Plant Resources
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• v.28 no.6
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• pp.718-726
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• 2015

In this study, the inhibitory activities of fifty plant extracts on IgE-mediated degranulation in the rat basophilic leukemia cell line (RBL-2H3 cells) were measured; the release of interleukin (IL)-4 and β-hexosaminidase from IgE-sensitized cells treated with the plant extracts was measured; and the effects of the plant extracts on cell viability were tested. The results of the analysis of plant extracts at 20 μg/ml, including the aerial part of Magnolia sieboldii K. Koch, exhibited suppressive activities upon the release of IL-4. Furthermore, several plant extracts including methanol extracted from Lindera erythrocarpa Makino (aerial part) at the same concentration significantly inhibited the release of β-hexosaminidase. Twenty-six of the plant extracts, including methanol extract of Weigela subsessilis (Nakai) L. H. Bailey (branch), showed a cell proliferation effect of over 80% at 100 μg/ml. In conclusion, the results suggest that the leaf/stem of Geum japonicum Thunb. and the stamen/ovary of Nelumbo nucifera Gaertn., which exhibited effective inhibition on β-hexosaminidase release and IL-4 release from mast cells and showed high cell viability, could be useful candidates as anti-allergy materials.

• Proceedings of the KIEE Conference
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• 2004.11b
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• pp.190-193
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• 2004

Optimal Power Flow (OPF) is becoming more and more important in the deregulation environment of power pool and there is an urgent need of faster solution technique for on-line application. So this paper presents parallel genetic algorithm-tap search for the solution of the OPF. The control variables modeled unit active power outputs, generator-bus voltage magnitudes and transformer-tap settings. A number of functional operating constraints, such as branch flow limits, load bus boltage magnitude limits and generator reactive capabilities are included as penalties in the fitness function. In parallel GA-TS, GA operators are executed for each process. If best fitness of the GA is not changed for several generations, TS operators are executed for the upper three populations to enhance the local searching capabilities. With migration operation, best string of each node is transferred to the neighboring node after predetermined iterations are executed. For parallel computing, we developed a PC-cluster system consisting of 8 PCs. Each PC employs the 2 GHz Pentium IV CPU and is connected with others through ethernet switch based fast ethernet. To show the usefulness of the proposed method, developed algorithm has been tested and compared on an IEEE 30-bus system in the reference paper. From the simulation results, we can find that the proposed algorithm is efficient for the OPF.

• Journal of KIISE:Computer Systems and Theory
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• v.32 no.8
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• pp.418-425
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• 2005

3D surface reconstruction is to make the original geometry of 3D objects from 2D geometric information. Barequet's algorithm is well known and most widely used in surface reconstruction. It tiles matched regions first, then triangulates clefts using dynamic programming. However it takes considerably long processing time while manipulating complex model. Our method tiles a simple region that does not have branches along minimally distant vertex pairs at once. When there are branches, our method divides contour lines into a simple region and clefts. We propose a fast and simple method that calculates medial axes using a minimum distance in cleft region. Experimental results show that our method can produce accurate models than the previous method within short time.