• Journal of international Conference on Electrical Machines and Systems
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• v.1 no.3
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• pp.282-288
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• 2012

A special pulsed electromagnetic actuator is presented whose plunger consists of two parts made of carbon steel and permanent magnet, respectively. The actuator exhibits a high holding force and small consumption of energy. The movement of the plunger is controlled by short current pulses. The static characteristics and other operation properties of the device are modeled numerically.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.841-842
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• 2006

This paper has proposed a serial 8-bit DAC for column driver circuits of mobile displays using LTPS TFTs. The DAC circuit takes very small area by using parasitic capacitance of column lines as sampling and holding capacitors. Moreover, the proposed DAC does not need the analog buffer, because the DAC operation is performed on the column lines. For the data driver circuits of 2-inch qVGA OLED panel, the DAC area is $84um{\times}800um$ and the simulated DAC power consumption is 8.5mW with 10-V supply voltage.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.49 no.5
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• pp.345-351
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• 2000

To improve the current waveform of diode rectifiers, we propose a new operating principle of the voltage diode rectifiers. In the conventional voltage rectifier circuit, relatively large capacitors are used to boost the output voltage, while the proposed circuit uses ones and a small reactor not boost the output voltage but improve the input current waveform. A circuit design method is shown and confirmed simulation. It explained that compared conventional PWM(Pulse-width modulated)inverter with HPWM(Half Pulse-width modulated)inverter. Proposed HPWM inverter eliminated dead-time by lowering switching loss and holding over-shooting. Output voltage and current of this paper were applied for real air-conditioner.

• Journal of Information Processing Systems
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• v.6 no.4
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• pp.575-596
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• 2010

Video-on-Demand services are increasing rapidly nowadays. The load on servers can be very high, even exceeding their capacity. For popular contents, we can use a Periodic Broadcast (PB) strategy using multicast to serve all clients. Recent development of PB uses multiple channels broadcasting for segments of movies in certain patterns, so that users only need to wait for a small segment to start the service. However, users need higher download capacity to download multiple segments at a time. In order to compensate for this, a proxy server can help to reduce download bandwidth requirements by holding some segments for a certain time. This research will focus on more recent PB schemes that couldn't be covered by previous Proxy-Assisted Periodic Broadcast strategies.

• Journal of Conservation Science
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• v.35 no.6
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• pp.664-669
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• 2019

Yeonpyo-beob is a method of manufacturing pigments using bamboo trunk and glue solution. Glue solutions of concentrations 1, 5, and 10% were employed to manufacture pigments, and the characteristics of pigment manufacturing were analyzed according to these concentrations. The pigment manufacturing process can be divided into holding and drying phases. The holding phase involves the sedimentation of relatively large particles, whereas the drying phase involves the sedimentation of small particles. The layers formed during the drying phase have almost similar forms regardless of the concentration of the glue solution. If the concentration of the glue solution is low in the holding phase, the particles are mixed and the formation of a layer is difficult. In contrast, when the concentration of the glue solution is higher, the layer of the pigment is more distinct. These results confirmed that the differences in viscosity due to the variation in the concentration of the glue solution affect the sedimentation velocity of the pigment particles, thereby affecting the formation of the layer of the pigment and the pigment manufacture. Consequently, applying 10% glue solution to reduce the sediment velocity is deemed suitable for the stratification of the pigment particles and the manufacture of pigments.

• The Journal of Internal Korean Medicine
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• v.22 no.2
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• pp.199-205
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• 2001

Background and Purpose : Transcranial doppler ultrasonography(TCD) is a noninvasive and nonradioactive technique for evaluation of the hemodynamics in large cerebral vessels. Sahyangsohap-won(SS) has been considered to be effective for the treatment of various disease, especially cerebrovascular, cardiovascular, and psychosomatoform disorders. But, there is no study about the effect of SS on the cerebral hemodynamics in humans. The aim of this study was to assess the effect of SS on the changes in cerebral hemodynamics and the dose-dependant effect by using TCD. Subjects and Methods : 30 healthy subjects were randomly divided into three group: group 1 took no drug, group 2 took SS one pill, and group 3 took SS 2 pills. Changes in the mean blood flow velocity(MBFV) and pulsatility index(PI) in the middle cerebral artery were evaluated by means of TCD. We obtained hypercapnia with breath-holding and evaluated cerebrovascular reactivity with the breath-holding index(BHI). Systolic blood pressure(SBP), diastolic blood pressure(DBP), and heart rate(HR) were measured by means of ambulatory blood pressure monitoring. In group 2 and group 3, the evaluations were performed during the baseline and were repeated at 20, 40, and 60 minutes after SS administration. In group 1, the evaluation was performed at corresponding time intervals. Results : In mean values of MSFV, PI, SSP, DBP, and HR, no stastically significant differences were found between the 3 groups. However, BHI values were significantly lower in groups 2 and 3 than in group 1 at 40 minutes after SS administration(P<0.05, group 1 vs group 2, group 1 vs group 3 by post-hoc analysis: Scheffe's test) but in dose-dependant effect, there was no difference between group 2 and group 3. Conclusion : These results suggest that SS can decrease vascular resistance in cerebral small arteries or arterioles and enhance their distensibility. Further studies on larger numbers of subjects are needed to confirm these effects and the dose-dependant effects.

• Molecules and Cells
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• v.26 no.2
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• pp.181-185
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• 2008

The effects of calcitonin gene-related peptide (CGRP) on pacemaker currents in cultured interstitial cells of Cajal (ICC) from the mouse small intestine were investigated using the whole-cell patch clamp technique at $30^{\circ}C$. Under voltage clamping at a holding potential of -70 mV, CGRP decreased the amplitude and frequency of pacemaker currents and activated outward resting currents. These effects were blocked by intracellular $GDP{\beta}S$, a G-protein inhibitor and glibenclamide, a specific ATP-sensitive $K^+$ channels blocker. During current clamping, CGRP hyperpolarized the membrane and this effect was antagonized by glibenclamide. Pretreatment with SQ-22536 (an adenylate cyclase inhibitor) or naproxen (a cyclooxygenase inhibitor) did not block the CGRP-induced effects, whereas pretreatment with ODQ (a guanylate cyclase inhibitor) or L-NAME (an inhibitor of nitric oxide synthase) did. In conclusion, CGRP inhibits pacemaker currents in ICC by generating nitric oxide via G-protein activation and so activating ATP-sensitive $K^+$ channels. Nitric oxide- and guanylate cyclase-dependent pathways are involved in these effects.

• Korean Journal of Human Ecology
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• v.20 no.1
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• pp.205-223
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• 2011

This study examines diagrams of space organization and classroom activity zoning through Korean Childcare Accreditation Criteria, and compares space diagrams with childcare facilities in Daejeon, and looks at similarities and differences between them. Space diagram from accreditation criteria show the classroom, adjoining toilets, napping areas, and community areas for playing, reading, cooking, teaching and holding materials. Classroom zone diagrams show 8 activity zones for entering, washing and toilet, making art, playing, reading, studying science, resting, playing role and wooden block. Six case studies in Daejeon, Korea were surveyed and classified into big, medium and small size facilities by the number of children. The space organization of case studies are similar to the diagrams, except that outdoor playground and indoor playrooms were not large enough at the small and medium size facilities. Classroom activity zoning was very similar to the conceptions, excluding the playarea from classroom, integrating the rest areas for reading, subdividing art into music and art, science, and into math and science, roleplay into roleplay and wooden block. In conclusion childcare centers in Daejeon are designed to the concept diagram of the accreditation criteria, with some flexibility, exclusion, integration, and subdivision of space and activity zones. It has been requested as to make each criteria fit to the facility sizes-big, medium and small.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.2-5
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• 1996

Orissa is one of the major rice growing states of India. The state covers an area of 15.54 mha with 6.00mha cultivable holding is 1.46 ha. The power input is much below the national average of 0.87 hp/ha. Recently, the Government of Orissa has accorded equal status to Agriculture as given to the Industry with determination to increase the power input for agricultural production to2.54 hp/ha so as to obtain an average rice productivity of 3.0t/ha. Appropriate power units so as to be available with in the purchasing power of the small size farm owners in lieu of a pair of bullocks appear to be the right approach and is found to be in line with the highly successful Japanese and Korean model of small farm mechanization . The state needs 0.25m units of small tillers and tractors per year. The present population of tractors and power tillers in the state is about 11000nos. In India, two manufactures in collaboration with Japanese firms started manufacturing of power tiller sin 197 . The present production of power tillers in the country is about 1000 unit per year which is inadequate to meet the demands of all the stats. To meet the demands of the Orissa state, three Chinese model power tillers imported by local agencies are being supplied to the farmers during the past two years. Encouraged by the demand of power tillers in the state, three local manufacturing units located at Bhubanewar have come up with their own model of light weight power tillers(1.5 to 3.0 hp) during the past one year. These machine have been evaluated in the farms of the university and have been found to be promising . There is a target of supplying during 1996-97. The local manufacturers are in need of international collaboration for technical knowhow to manufacture these machine economically to meet the requirement of the farmers.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.682-685
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• 2008

In globalization and information-oriented society, the domestic construction companies are competing with others in domestic and overseas market. To survive in the age of limitless competition, companies have to manage their performance systematically. However, domestic small and medium-sized companies which are holding a large majority don't have their own Performance Management System(PMS) yet. The purpose of this study is to analyze the existing PMS and to extract key drivers for developing PMS. Through case studies of KPI(UK), NBS(Chile), CII BM&M(USA) and SISIND-NET Project(Brazil), the key drivers are derived. Having these key drivers, this study suggested the conceptual model of PMS using benchmarking for small and medium-sized construction companies.