• Title/Summary/Keyword: Forward Reaction

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Effects of Targeted Knee Flexion Angle on the Biomechanical Factors of Upward and Downward Phases during Forward Lunge

  • Lim, Young-Tae;Park, Jun Sung;Lee, Jae Woo;Kwon, Moon-Seok
    • Korean Journal of Applied Biomechanics
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    • v.27 no.2
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    • pp.125-132
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    • 2017
  • Objective: The aim of this study was to investigate the effect of targeted knee flexion angle on biomechanical factors of knee joint between upward and downward phases during the forward lunge. Method: Eight elderly subjects (age: $22.23{\pm}1.51years$, weight: $69{\pm}6.63kg$, height: $174.88{\pm}6.85cm$) participated in this study. All reflective marker data and ground reaction force during a forward lunge were collected. The knee joint movement and reaction force and joint moment at maximum knee flexion angle were compared by repeated measures one-way analysis of variance (ANOVA) (p<.05). The peak knee joint reaction force and joint moment between upward and downward phases were compared by repeated measures two-way ANOVA (p<.05). Results: The anterior and vertical knee joint movements, reaction force, and extensor moment of $80^{\circ}$ targeted knee flexion condition at maximum knee flexion angle was greater than both $90^{\circ}$ and $100^{\circ}$ conditions (p<.05). The $80^{\circ}$ knee flexed angle condition had greater peak joint reaction force and extensor moment compared with both $90^{\circ}$ and $100^{\circ}$ conditions between upward and downward phases during the forward lunge. Conclusion: As the targeted knee joint flexion angle increases, knee joint movement and kinetic variables become greater during the forward lunge exercise.

Comparative Study of the Biomechanical Factors in Range of Motion, Muscle Activity, and Vertical Ground Reaction Force between a Forward Lunge and Backward Lunge

  • Park, Samho;Huang, TianZong;Song, Junyoung;Lee, Myungmo
    • Physical Therapy Rehabilitation Science
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    • v.10 no.2
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    • pp.98-105
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    • 2021
  • Objective: The purpose of this study was to examined the kinematic relationship and differences through the range of motion (ROM), muscle activity, and vertical ground reaction force (VGRF) during forward and backward lunge movements, which are effective in improving muscle strength and balance ability of the lower extremities, and to provide clinical information on more efficient lunge movements. Design: Cross-sectional study Methods: Fifteen adult males who met the selection criteria were tested for their dominant feet.Forward and backward lunges were then performed, and the ROM, muscle activity, and VGRF were measured for kinematic analysis during the lunge movement.The differences betweenthe forward lunge and backward lunge intervention were examined using a paired t-test. Results: A significant increase in the ROM of the knee and ankle was observed during the forward and backward lunges (p<0.05). In addition, in terms of the muscle activity, the peak values of the vastus medialis oblique (VMO) and VGRF also showed a significant increase in the forward lunge compared to the backward lunge (p<0.05). Conclusions: This study showed an increase in VGRF peak value, knee and ankle ROM, and VMO muscle activity during forward lunge. Based on these results, it is considered necessary to apply differently depending on the direction of progress in consideration of the musculoskeletal situation and physical ability during the lunge movement.

Kinetics and Optimization of Dimethyl Carbonate Synthesis by Transesterification using Design of Experiment

  • Lee, Kilwoo;Yoo, Kye Sang
    • Korean Chemical Engineering Research
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    • v.56 no.3
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    • pp.416-420
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    • 2018
  • A comprehensive kinetic study has been conducted on dimethyl carbonate synthesis by transesterification reaction of ethylene carbonate with methanol. An alkali base metal (KOH) was used as catalyst in the synthesis of DMC, and its catalytic ability was investigated in terms of kinetics. The experiment was performed in a batch reactor at atmospheric pressure. The reaction orders, the activation energy and the rate constants were determined for both forward and backward reactions. The reaction order for forward and backward reactions was 0.87 and 2.15, and the activation energy was 12.73 and 29.28 kJ/mol, respectively. Using the general factor analysis in the design of experiments, we analyzed the main effects and interactions according to the MeOH/EC, reaction temperature and KOH concentration. DMC yield with various reaction conditions was presented for all ranges using surface and contour plot. Furthermore, the optimal conditions for DMC yield were determined using response surface method.

The effect of Pd film evaporation condition on the kinetics of hydrogen absorption-desorption (Pd 박막 시료의 제작 조건이 수소 흡수-방출 동역학에 미치는 영향에 관한 연구)

  • Um, Dae-hyun;Yoo, Joung-gouk;Cho, Young-sin
    • Transactions of the Korean hydrogen and new energy society
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    • v.9 no.3
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    • pp.127-133
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    • 1998
  • This study was conducted to know to the effect of Pd film($180{\AA}$ thick) evaporation condition on the kinetics of hydrogen absorption-desorption. The activation energy of the forward reaction, the activation energy of the backward reaction, and the enthalpy were calculated by hydrogen absorption-desorption in ${\alpha}$-phase.($25{\sim}50^{\circ}C$ temperature) The activation energy of the forward reaction of Pd film, which is made at room temperature, is $6.4{\pm}0.4$ kcal/mol H and of the backward reaction $8.4{\pm}1.5$ kcal/mol H, which yields the reaction enthalpy -2kcal/mol H. The activation energy of forward reaction of Pd film, which is made at $300^{\circ}C$, is $-0.18{\pm}0.61$ kcal/mol H and of the backward reaction $-0.17{\pm}2.3$ kcal/mol H. The sample of $300^{\circ}C$ is more stable than the sample of room temperature in its struciural compactness and resistance value but standard error of result of $300^{\circ}C$ sample is higher than sample of room temperature do.

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Kinetics and Thermodynamic Studies on the Reaction of Cysteine with Cinnamaldehyde

  • Kim, Tae-Rin;Yun, Se-Joon;Park, Byung-Bin
    • Bulletin of the Korean Chemical Society
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    • v.7 no.1
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    • pp.25-29
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    • 1986
  • The reaction of cysteine with cinnamaldehyde have been studied kinetically and thermodynamically. It was found that the reaction proceeds in two steps; formation of the monoadduct by a Michael type addition followed by the nucleophilic attack of the second cysteine to the carbonyl carbon of the monoadduct to afford the thiazolidine derivative. A reaction profile for the reaction of cysteine with cinnamaldehyde was constructed based on the thermodynamic parameters analyzed for the forward and the reverse reactions. It was assumed that the second step of this reaction accompanies an intermediate, a Schiff base.

Detection of Phytoplasmas from Paulownia tomentosa, Syringa vulgaris and solidago vir-aurea var. gigantea Using Polymerase Chain Reaction (PCR) and Their Relationships (Polymerase Chain Reaction(PCR)을 이용한 오동나무, 라일락, 미역취의 Phytoplasma 검출 및 유연 관계)

  • 이준탁;이준탁;예미지;권오유
    • Korean Journal Plant Pathology
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    • v.12 no.2
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    • pp.191-196
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    • 1996
  • 위축, 황화, 총생 증상 등 전형적인 병징을 나타내는 phytoplasma에 감염된 식물에서 phytoplasma만을 특이적으로 검출하기 위하여 polymerase chain reaction(PCR) 방법을 이용하였다. Phytoplasma의 16S rRNA gence의 DNA 단편을 증폭하기 위하여 1.4 kb primers (forward, 5` -GTTGATCCTGGCTCAGGATT-3` 와 reverse, 5` -AACCCCGAGAACGTATTCACC -3`)를 사용하여 증폭한 결과, phytoplasma에 이병된 오동나무, 라일락 및 미역취에서는 약 1.4 kbp의 위치에서 특이 band가 검출되었으나 control로 사용한 건전주에서는 어떠한 band 검출되지 않았다. 위의 결과를 재확인 하기 위하여 약 0.5 kb의 primers(forward, 5` -ACGAAAGCGTGGGGAGCAAA-3` 와 reverse, 5` -GAAGTCGAGTTGCAGACTTC-3`)를 사용하여 증폭한 결과, 0.5 kb의 위치에서 특이 band가 검출되었으나 control로 사용한 건전주에서는 어떠한 band도 검출되지 않았다. Phytoplasma에 이병된 식물의 PCR 반응산물을 제한효소인 AluI으로 처리하 sruf과, 오동나무와 라일락에서는 동일한 band pattern을 나타내어 서로 유연관계가 가까운 phytoplasma인 것으로 생각되며, 미역취에서는 이들과는 다른 band pattern을 나타내어 오동나무와 라일락의 phytoplasma와는 유연관계가 먼 것으로 추측된다.

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Monetary Policy Rule under Inflation Targeting in Mongolia

  • Taguchi, Hiroyuki;Khishigjargal, Erdenechuluun
    • East Asian Economic Review
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    • v.22 no.4
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    • pp.531-555
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    • 2018
  • This article aims to review the monetary policy rule under inflation targeting framework focusing on Mongolia. The empirical analysis estimates the policy reaction function to see if the inflation targeting has been linked with a monetary policy rule emphasizing on inflation stabilization since its adoption in 2007. The study contributes to the literature by examining the linkage between Mongolian monetary policy rule and inflation targeting directly and thoroughly for the first time and also by taking into account a recent progress in the inflation targeting framework toward forward-looking mode. The main findings were: the Mongolian current monetary policy rule under inflation targeting is characterized as inflation-responsive rule with forward-looking manner (one quarter ahead); the inflation responsiveness is, however, weak enough to be pro-cyclical to inflation pressure; and the rule is also responsive to exchange rate due to the "fear of floating", which weakens the policy reaction to inflation and output gap.

A Interval Distance Calculation and Forward Collision Warning Algorithm for Vehicle Safety Communications on a Highway (고속도로에서 차량 안전 통신을 위한 거리 계산과 전방충돌사고경보 알고리즘)

  • Oh, Sang Yeob
    • Journal of Digital Convergence
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    • v.10 no.10
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    • pp.295-300
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    • 2012
  • Various forward collision warning algorithms have studied in order to protect a car accident. For this, in general, algorithms using an external device such as a camera and sensor generate a forward collision warning. However, if using the external device, it can occur errors due to device characteristics when there is rain or fog. Also, the prevention of a chain-reaction collision is insufficient because the system generates a warning in case of only vehicle having a forward collision danger. If it combines the vehicle safety communications, the method becomes a solution to protect a chain-reaction collision. So, In this paper, we proposes a improved forward collision warning algorithm using the wireless communication technique, driver's information, breaking distance, and velocity. And we compare and analyze our algorithm and previous algorithms.

The Effects of Chronic Ankle Instability on Postural Control during Forward Jump Landing (전방 점프 착지 시 만성 발목 불안정성이 자세 조절에 미치는 영향)

  • Kim, Kew-wan;Jeon, Kyoungkyu;Park, Seokwoo;Ahn, Seji
    • Korean Journal of Applied Biomechanics
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    • v.32 no.1
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    • pp.9-16
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    • 2022
  • Objective: The purpose of this study was to investigate how the chronic ankle instability affects postural control during forward jump landing. Method: 20 women with chronic ankle instability (age: 21.7 ± 1.6 yrs, height: 162.1 ± 3.7 cm, weight: 52.2 ± 5.8 kg) and 20 healthy adult women (age: 21.8 ± 1.6 yrs, height: 161.9 ± 4.4 cm, weight: 52.9 ± 7.2 kg) participated in this study. For the forward jump participants were instructed to stand on two legs at a distance of 40% of their body height from the center of force plate. Participants were jump forward over a 15 cm hurdle to the force plate and land on their non-dominant or affected leg. Kinetic and kinematic data were obtained using 8 motion capture cameras and 1 force plates and joint angle, vertical ground reaction force and center of pressure. All statistical analyses were using SPSS 25.0 program. The differences in variables between the two groups were compared through an independent sample t-test, and the significance level was to p < .05. Results: In the hip and knee joint angle, the CAI group showed a smaller flexion angle than the control group, and the knee joint valgus angle was significantly larger. In the case of ankle joint, the CAI group showed a large inversion angle at all events. In the kinetic variables, the vGRF was significantly greater in the CAI group than control group at IC and mGRF. In COP Y, the CAI group showed a lateral shifted center of pressure. Conclusion: Our results indicated that chronic ankle instability decreases the flexion angle of the hip and knee joint, increases the valgus angle of the knee joint, and increases the inversion angle of the ankle joint during landing. In addition, an increase in the maximum vertical ground reaction force and a lateral shifted center of pressure were observed. This suggests that chronic ankle instability increases the risk of non-contact knee injury as well as the risk of lateral ankle sprain during forward jump landing.

Study on the Correlation Between Physical Function and Forward Head Posture in Spastic Diplegia (경직형 양하지 뇌성마비 아동의 전방머리자세와 신체기능간의 상관관계)

  • Jo, Yong-Eun;Lee, Eun-Ju
    • PNF and Movement
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    • v.19 no.2
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    • pp.163-172
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    • 2021
  • Purpose: This study investigated the correlation between physical function and forward head posture in spastic diplegia. Methods: The subjects of this study were 10 spastic diplegia patients. We took pictures of the subjects' craniovertebral angle with a digital camera to determine the degree of forward head posture and then analyzed them using the NIH image J program. The physical function test used the TCMS, the BBT, and a spirometer. The data in this study were measured using SPSS version 23.0, and the statistical significance level α was 0.05. A Pearson correlation coefficient analysis was performed to identify the correlation between the degree of the subject's head forward position and physical function. Results: When we performed the BBT and spirometer tests, the subjects' forward head postures were not correlated (p < 0.05). However, with the TCMS, there was a strong correlation between the forward position of the head and balance, with balance decreasing as the head position increased (p < 0.05). Conclusion: Spastic diplegia patients with severe forward head posture showed problems with static balance, dynamic balance, and equilibrium reaction when sitting. Intervention on the right posture and preventive activities will be needed to improve the health of spastic diplegia patients and prevent future problems with physical function.