• Journal of Biosystems Engineering
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• 제24권4호
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• pp.365-372
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• 1999

Physical characteristics of stem (ile., length and diameter) and branch, and detachment force of mature and immature fruits of 12 species of the Lycium chinese Mill at a cultivar were determined. The number of stems and branches were counted after the first and second pruning of each plant. Length and diameter of the stem were average of 113.5 cm and 9.5 mm for 12 species of the Lycium chinese Mill, respectively. Average number of stem and number of branch after the first and second pruning in each plant were 5, 30, and 61, respectively. Diameter of major and minor axis of the fruit was average of 13.8mm and 8.3mm, respectively, and the sphericity of fruits was average of 0.7 for 12 species of Lycium chinese Mill. Detachment force of mature and immature fruits was average of 1 N and 2.7 N, respectively, for 12 species of the Lycium chinese Mill. The maximum and minimum detachment force of the mature fruits was 2.06 N and 0.39 N, respectively, and that of the immature fruits was 3.72 N and 1.27 N, respectively. The force-weight ratio showed a decreasing trend as the weight of fruit increasing for all samples.

• Journal of Oral Medicine and Pain
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• 제15권1호
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• pp.37-44
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• 1991

The author has synchronously recorded average electromyographic activities of temporalis anteriors and masseter muscles and the maximum bite force on the mandibular first molar on the prferred chewing side. These activities were recorded in order to study the EMG activity pattern of the working side and the balancing side to maximum bete force and functioning state of muscle in 30 patients with TMD and in 30 healthy subjects as controls. The results were as follows : 1. The maximum bite force on the mandibular first molar on the preferred chewing side was 20.63kg in TMD patients and 53.30kg in the healthy subjects(p<0.01). The maximum bite force in TMD patients was 38.7% of the healthy subjects. 2. The average electromyographic activities of temporalis anterioris and masseter muscles on the working side and the balancing side during maximum bite force were lower in TMD patients than in the healthy subjects(p<0.01). The average electromyographic activities of each muscle in TMD patients were 61.0%-62.8% of the healthy subjects. 3. The proportionalities of average electromyographic activities of temporalis anteriors and masseter muscles on the working side and the balancing side to maximum bite force were greater in TMD patients than in the healthy subjects(p<0.01). 4. Between the working side and the balancing side, the proportionality of average electromyographic activity of temporalis anterior to maximum bite force on the working healthy subjects (p<0.01). The proportionality of average electromyographic activity of working side and the balancing side in both groups (p<0.05).

• 한국자동차공학회논문집
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• 제18권3호
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• pp.116-126
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• 2010

The Korean rolling stock safety regulation stipulates that the collision deceleration of a car body should be maintained under average 5g and maximum 7.5g during train collisions. One-dimensional dynamic model of a full rake train, which is made up of nonlinear springs/bars-dampers-masses, is often used to estimate the collision decelerations of car bodies in a basic design stage. By the way, the previous studies have often used some average force-deformation curve for energy absorbing structures in rolling stock. Through this study, we intended to analyse how much the collision deceleration levels are influenced by the initial peak force modeling in the one-dimensional force-deformation curve. The numerical results of the one-dimensional dynamic model for the Korean High-Speed Train show that the initial peak force modeling gives significant effect on the collision deceleration levels. Therefore the peak force modeling of the force-deformation curve should be considered in one-dimensional dynamic model of a full rake train to evaluate the article 16 of the domestic rolling stock safety regulations.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 D
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• pp.2352-2354
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• 2003

An apparatus and method for imposing a desired average radial force on tire by calculating the current average force between the tire and load wheel based on the average radial force and radial distance between the tire load wheel over the last previous complete revolution of the tire, the spring constant of the tire and the current radial distance between the tire and the load wheel.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2011년도 춘계학술대회
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• pp.157-158
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• 2011

골프채로 공을 치면 골프공은 충돌로 인하여 커다란 속도로 긴 거리를 날아간다. 본 논문에서는 골프채와 골프공이 충돌 한 후의 운동량의 크기를 구하고자 한다. 또한 골프채와 골프공의 충돌 시간과 공에 작용한 평균력을 구한다. 우리는 물체에 작용하는 충격량은 물체의 운동량의 변화화 같음을 알 수 있다. 그리고 평균력은 시간에의해 변하는 힘 대신에 어떤 물체의 실제 힘과 똑같은 충격량을 주는 일정한 힘임을 알 수 있다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2008년도 추계학술대회 논문집
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• pp.323-324
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• 2008

• 콘크리트학회지
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• 제9권4호
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• pp.207-214
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• 1997

본 연구는변형구속에 의해 생기는 축력이 철근콘크리트 휨부재의 역학적 거동과 평균 균열간격에 미치는 영향을 검토하기 위해 수행되었다. 이를 위하여 변형구속 및 무구속 조건하에서의 휨강도와 휨강성을 실험으로 구하였으며, 또한 축방향 구속을 받는 휨부재의 평균 균열간격을 예측하는 식을 제안하였다.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
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• pp.58-65
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• 2000

This study is concerned about the verification and the implementation of a mechanical model for the force system in end milling. The model is based on the relationship between the cutting forces and the chip thickness. The components of the model are based on the average cutting forces which are experimentally obtained. And, both instantaneous and average force system characteristics are described as a function of cut geometry and a feed rate. This model employed two specific cutting forces, instantaneous and average specific cutting force, and the models which obtained using two cutting forces were compared and analyzed. In this study, cutter deflection with respect to the center of rotation is considered, which is a major part of the tool run-outs. The effect of run-out on the cutting forces is also discussed. The relationships among the run-out parameters, cutting parameters and the resulting force system characteristics are presented. In all cases, for the down milling with a right hand helix cutter is considered.

• 한국운동역학회지
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• 제30권2호
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• pp.145-154
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• 2020

Objective: The purpose of this study was to determine the relationship between impact and shear peak force, and tibia-accelerometer variables during running. Method: Twenty-five male heel strike runners (mean age: 23.5±3.6 yrs, mean height: 176.3±3.3 m/s, mean mass: 71.8±9.7 kg) were recruited in this study. The peak impact and anteroposterior shear forces during treadmill running (Bertec, USA) were collected, and impact shock variables were computed by using a triaxial accelerometer (Noraxon, USA). One-way ANOVA was used to test the influence of the running speed on the parameters. Pearson's partial correlation was used to investigate the relationship between the peak impact and shear force, and accelerometer variables. Results: The running speed affected the peak impact and posterior shear force, time, slope, and peak vertical and resultant tibial acceleration, slope at heel contact. Significant correlations were noticed between the peak impact force and peak vertical and resultant tibia acceleration, and between peak impact average slope and peak vertical and resultant tibia acceleration average slope, and between posterior peak (FyP) and peak vertical tibia acceleration, and between posterior peak instantaneous slop and peak vertical tibial acceleration during running at 3 m/s. However, it was observed that correlations between peak impact average slope and peak vertical tibia acceleration average slope, between posterior peak time and peak vertical and resultant tibia acceleration time, between posterior peak instantaneous slope and peak vertical tibial acceleration instantaneous slope during running at 4 m/s. Conclusion: Careful analysis is required when investigating the linear relationship between the impact and shear force, and tibia accelerometer components during relatively fast running speed.

• 한국농공학회지
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• 제35권4호
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• pp.76-85
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• 1993

The purpose of this study was to analyze the wind force distribution on the two single-span arched plastic house depending upon the house spacing and wind direction, which may provide the fundamental criteria for the structural design. In order to specify the wind force distribution, the variation of the wind force coefficients, the mean wind force coefficients and the drag force coefficients were estimated from the wind tunnel test data. The results obtained are as follows : 1. At the wind direction of 90$^{\circ}$, there was a typical span interval at which the maximum negative pressure was occured at the edge of the inside walls. 2. In the consideration of wind loads, the wind force coefficients estimated from independent single-span arched plastic house should not be directly applied to the structural design on the double houses separated. 3. The average maximum negative wind force on the inside walls was occured at the wind direction of 90$^{\circ}$, and the variations depending on the span intervals was not significant. 4. The average maximum drag force was occured at the wind direction of 300, and the magnitude of drag force was more significant at the first house. As the distance between two houses was increased, the drag force was slightly increased for every wind direction.