• Advances in aircraft and spacecraft science
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• v.2 no.3
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• pp.275-302
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• 2015

Theoretical and numerical assessments of approximate evaluations and simplified analyses of piezoelectric structures transverse shear modal effective electromechanical coupling coefficient (EMCC) are presented. Therefore, the latter is first introduced theoretically and its approximate evaluations are reviewed; then, three-dimensional (3D) and simplified two-dimensional (2D) plane-strain (PStrain) and plane-stress (PStress) piezoelectric constitutive behaviors of electroded shear piezoceramic patches are derived and corresponding expected short-circuit (SC) and open-circuit (OC) frequencies and resulting EMCC are discussed; next, using a piezoceramic shear sandwich beam cantilever typical benchmark, a 3D finite element (FE) assessment of different evaluation techniques of the shear modal effective EMCC is conducted, including the equipotential (EP) constraints effect; finally, 2D PStrain and PStress FE modal analyses under SC and OC electric conditions, are conducted and corresponding results (SC/OC frequencies and resulting effective EMCC) are compared to 3D ones. It is found that: (i) physical EP constraints reduce drastically the shear modal effective EMCC; (ii) PStress and PStrain results depend strongly on the filling foam stiffness, rendering inadequate the use of popular equivalent single layer models for the transverse shear-mode sandwich configuration; (iii) in contrary to results of piezoelectric shunted damping and energy harvesting popular single-degree-of-freedom-based models, transverse shear modal effective EMCC values are very small in particular for the first mode which is the common target of these applications.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.1B
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• pp.89-100
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• 2010

The performance evaluation of a conventional Wave Resonator at the entrance of harbors against solitary wave has been performed using 3D numerical wave flume. A wave resonator has been designed for the attenuation of the transmitted wave energy by trapping the short periodic incident waves only. In this study, however, the controlled performance of the wave resonator by its various widths has been numerically investigated for solitary waves. Source distribution method based on the Green function and the 3D one-field Model for immiscible TWO-Phase flows (TWOPM-3D) using 3D numerical wave flume were used for the short-periodic waves and the solitary waves, respectively, and these models were verified through the comparisons with the previous experimental and numerical results by other researchers. It was confirmed that the wave resonator is effective enough to control the solitary waves as well as the periodic waves when it compares with the case of no resonance system. Further, it was found that there is the optimal width of a wave resonator to attenuate the target solitary waves.

• Korean Journal of Health Education and Promotion
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• v.14 no.1
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• pp.11-21
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• 1997

We carried out this study to analyze the effectiveness through health education program in short term which was performed to use the special subject activities. This study was conducted on 63 students who were first grade in S Junior High School from Dec. 1995 to Feb. 1996. To analyze the effectiveness, we performed the Pretest, 1st Posttest, and 2nd Posttest for learned health knowledge. The results were as follows: 1. Most of the students(69.8%) responded that their health were good, and they got the information for health through Mass Com.. The students who had experience of health education were 15.9%, and the 77.8% of the respondents needed the health education. 2. The means of health knowledge on tests were 18.2(Pretest}, 21.5(1st Posttest), and 21.4(2nd Posttest). Increase of health knowledge between Pretest and 1st Posttest was 10.9%. 3. The mean of differences between Pretest and 1st Posttest was 3.26, it was significant(p〈0.01). And the mean of differences between Pretest and 2nd Posttest was 3.19, it was significant(p〈0.01);however, the mean of differences between 1st Posttest and 2nd Posttest was not significant(p=0.2514). 4. The significant main contents were Health Facilities(d=0.42), Pregnancy and Labor(d=0.39), Sex Education(d=0.29), Personal Hygiene(d=0.35), Safety Education (d=0.66), and Drug Abuse(d=0.60)(p〈0.01)

• Clinical and Experimental Pediatrics
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• v.49 no.3
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• pp.312-316
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• 2006

Purpose : Growth hormone(GH) has been recognized as an effective treatment for short children born small for their gestational ages(SGA), and nowadays it has been widely used for the treatment of short children born SGA. The aim of this study is to assess the efficacy of GH treatment for the children born SGA. Methods : The study population was made of 40 short children born SGA with GH-treated(n=26) and untreated control group(n=14). In order to evaluate the effect of GH treatment, the changes in standard deviation scores(SDS) of the GH-treated group were compared to the changes in SDS before and after treatment from the control group in the same period. Results : There were no differences between the GH-treated group and the control group in gestational age, birth weight, chronological age, target height and the period of follow-up observation; however, the GH-treated group had lower height SDS($-3.3{\pm}0.9$) than the control group($-2.4{\pm}0.4$) before treatment(P<0.05). The GH-treated group had gained $1.2{\pm}1.0$ height SDS during GH treatment while the control group had gained $0.5{\pm}0.6$ height SDS. In the GH treatment group, HDL-cholesterol increased from $48.5{\pm}9.9mg/dL$ to $56.1{\pm}8.7mg/dL$(P<0.05) and LDL-cholesterol decreased from $88.1{\pm}23.3mg/dL$ to $76.4{\pm}19.4mg/dL$(P<0.05) after treatment. There were no changes in total cholesterol, triglyceride, free fatty acid and fasting blood sugar. IGF-I increased from $224.9{\pm}191.3{\mu}g/L$ to $443.2{\pm}152.5{\mu}g/L$(P<0.05) and IGFBP-3 also increased from $3.7{\pm}1.3mg/L$ to $5.6{\pm}1.2mg/L$(P<0.05). Conclusion : We conclude that growth hormone treatment is effective in the treatment of short children born SGA.

• Korean Journal of Applied Biomechanics
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• v.17 no.3
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• pp.51-60
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• 2007

The purpose of this study was to kinematically analyze the differences between short(2.17 m) and long(10.94 m) putting stroke motions. Thirteen male professional golfers were participated in this study. Experiment was conducted on the artificial grass mat in the gymnasium. Kinematic data were collected by the 60 Hz Kwon3D motion analysis system. Differences were compared by SPSS paired t-test and one-way ANOVA. Duncan was used for post-hoc test and a=.05. The results were as follows: 1. Ground projected trajectory of the putter head were statistically straight during both short and long putts. 2. There was no consistent alignment tendency among shoulder, hip, and stance alignments. However stance alignment was consistent between short and long putts. Thus it is assumed that professional golfers align their body based on their stance alignment. 3. During putting, shoulder rotated not only up and down but also right and left. 4. Left and right elbow distance was maintained during all phases of the putts for both short and long putts. 5. Inter foot distance of long putting was longer than that of short putting.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.10
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• pp.941-944
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• 2016

This paper proposes 24 GHz power amplifier for automotive collision avoidance and surveillance short range radar using Samsung 65-nm CMOS process. The proposed circuit has a 2-stage differential power amplifier which includes common source structure and transformer for single to differential conversion, impedance matching, and power combining. The measurement results show 15.5 dB maximum voltage gain and 3.6 GHz 3 dB bandwidth. The measured maximum output power is 13.1 dBm, input $P1_{dB}$ is -4.72 dBm, output $P1_{dB}$ is 9.78 dBm, and maximum power efficiency is 17.7 %. The power amplifier consumes 74 mW DC power from 1.2 V supply voltage.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.5
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• pp.846-858
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• 2008

This study was designed to propose a method to draft bodice block pattern from 3D body scan data. Subjects were ten elderly women in their 60's, who wear basic size(B: 94cm, W: 82cm) garment. Scanning was done using 3D whole body scanner(WB4, Cyberware). Measurements for 3D data and cross section were attained using Auto CAD, by which a upper bodice pattern for elderly women was drawn on the basis of short measured method. The results are as following: As for most items, no significant differences were shown between measurements from Martin's anthropometry and those from 3D scan data, suggesting measurement from 3D scan data could be used to draft a pattern. The drafting equations acquired were as follows; width of pattern=B/2+5.5, width of waist=W/2+3.5cm, dart amount=8cm. Dart distributions were 23%(B.P.) : 20%(front armpit) : 17%(side seam) : 18%(back armpit) : 15%(back protruded point) : 7% (center back line). Through wearing test using 5-point Likert scale, resultant pattern was evaluated as appropriate for elderly women's pattern to get over 4 point. As a result, it might be said that 3D scanning application is effective for elderly women in that it doesn't take time so much as Martin's anthropometry and that their body shape vary compared with those of young women.

• JSTS:Journal of Semiconductor Technology and Science
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• v.9 no.3
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• pp.136-147
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• 2009

In this paper we analyze the influence of source/drain (S/D) extension region design for minimizing short channel effects (SCEs) in 25 nm gate length single and double gate Silicon-on-Insulator (SOI) and Germanium-on-Insulator (GOI) MOSFETs. A design methodology, by evaluatingm the ratio of the effective channel length to the natural length for the different devices (single or double gate FETs) and technology (SOI or GOI), is proposed to minimize short channel effects (SCEs). The optimization of non-overlapped gate-source/drain i.e. underlap channel architecture is extremely useful to limit the degradation in SCEs caused by the high permittivity channel materials like Germanium as compared to that exhibited in Silicon based devices. Subthreshold slope and Drain Induced Barrier Lowering results show that steeper S/D gradients along with wider spacer regions are needed to suppress SCEs in GOI single/double gate devices as compared to Silicon based MOSFETs. A design criterion is developed to evaluate the minimum spacer width associated with underlap channel design to limit SCEs in SOI/GOI MOSFETs.

• Journal of the Korean earth science society
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• v.32 no.6
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• pp.560-574
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• 2011

Satellite images that have been obtained periodically and continuously are very effective data to monitor the changes of Earth's surface. Traditionally, the studies on change detection using satellite images have mainly focused on comparison between two results after analyzing two images respectively. However, the interests in researches to catch smooth trends and short duration events from continual multi-temporal images have been increased recently. In this study, we introduce and test an approach based on 3D wavelet transform to analyze the multi-temporal satellite images. 3D wavelet transform can reduce the dimensions of data conserving main trends. Also, it is possible to extract important patterns and to analyze spatial and temporal relations with neighboring pixels using 3D wavelet transform. As a result, 3D wavelet transform is useful to capture the long term trends and short-term events rapidly. In addition, we can expect to get new information through sub-bands of 3D wavelet transform which provide different information by decomposed direction.

• Transactions on Electrical and Electronic Materials
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• v.17 no.2
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• pp.118-120
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• 2016

A coplanar waveguide employing periodic 3D coupling structures (CWP3DCS) was developed for application in miniaturized on-chip passive components on silicon radio frequency integrated circuits (RFIC). The CWP3DCS showed the shortest wavelength of all silicon-based transmission line structures that have been reported to date. Using CWP3DCS, a highly miniaturized impedance transformer was fabricated on silicon substrate, and the resulting device showed good RF performance in a broad band from 4.6 GHz to 28.6 GHz. The device as was 0.04 mm² in size, which is only 0.74% of the size of the conventional transformer on silicon substrate.