• Clinics in Shoulder and Elbow
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• v.25 no.3
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• pp.188-194
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• 2022

Background: Medial elbow laxity develops in throwing athletes due to valgus forces. Medial elbow instability in professional, collegiate, and high school athletes is well documented; however, the medial elbow of young throwing athletes has received less attention. This study investigated the medial elbow and common flexor tendon during applied elbow valgus stress of youth baseball players. Methods: The study included 15 participants. The medial elbow width and thickness of the common flexor tendon were measured on ultrasound images. Results: No significant side differences in medial elbow width or common flexor tendon were found at rest or under applied valgus stress. At rest, the medial elbow joint width was 3.34±0.94 mm on the dominant side and 3.42±0.86 mm on the non-dominant side. The dominant side increased to 3.83±1.02 mm with applied valgus stress, and the non-dominant side increased to 3.96±1.04 mm. The mean flexor tendon thickness was 3.89±0.63 mm on the dominant side and 4.02±0.70 mm on the non-dominant side. Conclusions: These findings differ from similar studies in older throwing athletes, likely because of the lack of accumulated stress on the medial elbow of youth throwing athletes. Maintaining elbow stability in young throwing athletes is a vital step to preventing injury later in their careers.

• 전기의세계
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• v.29 no.11
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• pp.733-741
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• 1980

A novel six-step current source inverter (CSI) with DC-side commutation and energy rebound capability is presented with detailed explanation of the circuit operation. The prposed inverter can operate in a very wide range of frequency and load variation by employing DC-side commutation. Also, the energy rebound makes the use of low voltage SCR's possible and increases the inverter efficiency. Motor operation is also possible in four quadrants in this proposed current source inverter. The advantages of the proposed CSI over conventional ones are described and experimental results are given in oscillograms.

• Journal for History of Mathematics
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• v.14 no.1
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• pp.17-26
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• 2001

Ri, Sang-Hyeok(1810-\ulcorner) explained in detail and repeatedly solution of problems which find the area and diameter of inscribed and circumscribed circles of regular polygons from a side and find a side of regular polygons from the area of the book Su-Ri-Jeong-On in the chapter ‘Gak-Deung-Byeon-Hyeong-Seup-Yu’ of his book San-Sul-Gwan-Kyeun. The explanation of each question describes the procedure to make the equation in detail, but only presents the solution with few step to solve.

• Transactions of Materials Processing
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• v.24 no.6
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• pp.400-404
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• 2015

For mass production of stamped parts, which require complicated in-press operations, it is always advisable to use a progressive die set. It is difficult to choose a progressive die set if the stamped parts need to be deep drawn and especially if they are unsymmetrical. Because unsymmetrical deep drawing parts are very sensitive to the effect of weight during moving to the next step, they are hard to exactly locate on the die face. An automotive seat side cushion panel is about 80mm high, unsymmetrical and its low edge needs hemming, so it is hard to produce even using a progressive die set. In the current paper a progressive stamping for seat side cushion panel was examined. Five strip bridges were considered to be strong enough to move to the next die as predicted by the CAE analysis.

• Journal of the Korean Ceramic Society
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• v.48 no.4
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• pp.263-268
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• 2011

ZnO hexagonal rods grown in aqueous solution can be changed into a tubular shape by two-step aging in the course of the growing process. In the first step, hexagonal ZnO rods is grown by aging at $90^{\circ}C$ under a highly supersaturated aqueous solution giving rise to a fast precipitation rate. Meanwhile, during the second step aging at $60^{\circ}C$ in the same aqueous solution, the hexagonal polar face (001) having higher surface energy than (010) side planes dissolves to minimize surface energy. Hence the flat (001) face changes to a craterlike face and the hexagonal rod length of ZnO decreases at an initial-stage of this step aging. The formation of the (101) wedge-type faces is ascribed to the resultant of competitive reactions between the dissolution of polar face minimizing the surface energy which is a dominant reaction at the initial stage and the precipitation reaction dissipating supersaturation. At a later stage of the second-step the reaction rates of these two processes in the aqueous solution become similar and the overall reaction is terminated.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.1
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• pp.91-96
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• 1987

Plasma etching can obtain less damaged etch surface than reactive ion etching. This study was performed to get anisotropic etching characteristics of Si using two step etching technique with C2CIF5 and SF6 gas mixture. The results show that the etch rate and aspect ratio of silicon was increased with increment of SF6 contents. The bulging phenomenon on trench side wall in the plasma one-step etching technique was eliminated by the two step etching technique. The anisotropy was decreased from 12(at 120m Torr) to 2.2(at 400m Torr) with increasing the chamber pressure. At the low rf power (350 watts) anisotrpy of silicon was obtained 7 lower than that of high rf power (650 watts. A:~9). In Summary we obtained anisotropic etching profiles of silicon with e 6\ulcornerm depth by using the plasma two-step etching technique.

• Journal of The Korean Association For Science Education
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• v.34 no.5
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• pp.469-478
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• 2014

To provide students an alternative image of science and scientist, we developed five lesson plans that include scientists' joy, anger, sorrow, and pleasure in their life. Through the 10 hour lessons with the five topics, we investigated the effect of our program on students' image change toward scientists, their science learning, and their career development in science field. Twenty high school students participated in our program and five of them were analyzed. The qualitative data included opinionnaire survey before and after the program, field note, video recording, students' worksheets, and interview. The science episode lessons that reflect the human side of scientists were designed in five steps. The first step is the one about imaging of scientists, the second step is the one about reading scientists' episode in their life, the third step is the one about investigating human side of scientists, the fourth step is the one about feeling sympathy in scientists' context, and the last step is the one about judging human side of scientists. Students participated in this program got to feel familiarity in scientists as well as confidence in science. By obtaining the alternative image of scientists after the class, it is expected that students will play roles of well-prepared supporters with scientific literacy.

• Journal of Electrical Engineering and Technology
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• v.11 no.2
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• pp.300-308
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• 2016

Application of demand-side resources to automatic generation control (AGC) has a great significance for improving the dynamic control performance of power system frequency regulation. This paper investigates the possibility of providing regulation services by demand-side energy storage in electric vehicle battery swapping stations (BSS). An interaction framework, namely station-to-grid (S2G), is presented to integrate BSS energy storage into power grid for giving benefits to frequency regulation. The BSS can be regarded as a lumped battery energy storage station through S2G framework. A supplementary AGC method using demand-side BSS energy storage is developed considering the vehicle user demand of battery swapping. The effects to the AGC performance are evaluated through simulations by using a two-area interconnected power grid model with step and random load disturbance. The results show that the demand-side BSS can significantly suppress the frequency deviation and tie-line power fluctuations.

• Physical Therapy Rehabilitation Science
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• v.2 no.2
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• pp.104-110
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• 2013

Objective: The purpose of this study was to investigate the effects of intensive gait training with body weight support treadmill training on gait and balance in stroke disability patients. Design: Randomized controlled trial. Methods: Twenty-six stroke patients (20 men and 6 women) participated in this study. All subjects were hospitalized patients. They were randomly divided into two groups: the experimental group (body weight supported treadmill training group, n=14) and control group (treadmill group, n=12). The mean ages were 52.07 years (experimental group) and 53.83 years (control group). Subjects in both groups received conventional training 10 times/wk. Subjects in the experimental group practiced body weight supported treadmill training for 30 minutes a day, 3 day/wk. Subjects in the control group practiced treadmill training for 30 minutes. The Berg Balance Scale (BBS) and GAITRite were used to evaluate balance and gait parameters (step length, cadence and gait speed) before and after the intervention. Results: BBS scores in the experimental group showed significantly greater improvement ($4.33{\pm}1.54$), compared with the control group (p<0.05). Significantly greater improvement in the gait speed ($24.13{\pm}4.53$ cm/s), affected side step length ($10.40{\pm}3.42$ cm), sound side step length ($11.97{\pm}3.29$ cm), and cadence ($23.88{\pm}5.52$ step/min), compared with the control group (p<0.05). Conclusions: Intensive gait training with Body Weight Support Treadmill Training may improve gait and balance in subacute stroke.

• Journal of the Korea Society of Computer and Information
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• v.29 no.5
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• pp.123-129
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• 2024

CPR is very important to paramedics, but the chest compression performed while on the move main stretcher is less accurate. The purpose of this study is to find out the difference between performing chest compression on the side of the main stretcher using C-step and on the patient's over the belly in order to increase the effect of CPR on the main object while on the move. As a result of the study, the appropriate depth (t=4.132, p=.000) and speed (t=7.177, p=.000) were shown in the group to which the C-step was applied, and the accuracy was higher (t=6.774, p=.000). In addition, it was found that there were few location defects (t=-5.197, p=.000) and too shallow errors (t=-2.948, p=.008) in the group to which the C-step was applied. In conclusion, mounting a C-step on the main stretcher seems to help improve the quality of chest compression, and it is thought that this will increase the efficiency of chest compression.