• Title/Summary/Keyword: relative velocity

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The effect of customer participation on encounter satisfaction: moderating of participation and commitment velocity (고객참여의 접점만족에 미치는 영향: 참여속도와 몰입속도의 조절효과 검증)

  • Ahn, Jinwoo
    • Management & Information Systems Review
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    • v.38 no.3
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    • pp.81-96
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    • 2019
  • Because the service is characterized by simultaneous production and consumption, the customer must participate directly in the delivery and production process of the service. For this reason, the variable Customer Participation has aggregated many empirical results in the service marketing field. Recent research on customer participation has focused on the relationship marketing, and is empirically identifying the relevance of customer participation and relative value of relationship marketing. These findings indicate that customer participation should be understood in a relationship between customers and service firms. Using commitment velocity and customer participation velocity considering dynamic of the relationship, this study aims to re-examine the relationship between customer participation and encounter satisfaction which is the foundation of relationship formation. Multiple regression analysis and hierarchical regression analysis are used as research methods. The study found that customer participation has a direct positive effect on encounter satisfaction, and that commitment velocity and customer participation velocity also have a significant effect on encounter satisfaction. However, all assumptions that were expected to moderate the impact of customer participation on encounter satisfaction were rejected. Although the study failed to identify the moderating role, it was clear about the impact on the encounter satisfaction of commitment velocity and customer participation velocity. Applying them to a wider variety of service types provided an opportunity to identify the value of the study, and to broaden the scope of the study suing these variables.

Effects of knee flexor isokinetic training on Knee muscles strength and walking speed in hemiplegia (뇌졸중 환자에서 슬관절 굴근의 등속성운동이 슬관절 근력 및 보행에 미치는 영향)

  • Jang, Moon-Heon
    • Journal of Korean Physical Therapy Science
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    • v.7 no.2
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    • pp.711-725
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    • 2000
  • The purpose of this study was to determine the effects of knee flexor isokinetic training on the mean peak torque of knee muscles and hamstrings-to-quadriceps ratio(H/Q ratio) in hemiplegia able to walk independently for more than 10 meters, to analyze the effect of torque increasing on functional aspects; fatigability and ambulation times, also. Forty-one adult subjects with hemiplegia secondary to a stroke partipated in this study. All participants were in/out patients at the College of Medicine, Pocheon CHA University, Pundang CHA General Hospital. The patients were allocated to two groups: one group exclusively for isokinetic maximal voluntary knee flexor training at $150^{\circ}$/sec(n=20) and the other exclusively for isokinetic maximal voluntary knee flexor training from $30^{\circ}$/sec to $150^{\circ}$/sec (n=21) gradually. The allocation was performed according to patient age, sex, affected side to minimize imbalance between the two training groups. Training was carried out from February 14th, 2000 to April 15th, 2000. Analysis of the data was done by means of t-test, x2-test, paired t-test, ANOVA, and multiple regression analysis. The results of this study were as follows: 1. There were no significant differences between the two groups in mean peak torque of knee muscles and relative decreases in knee extensor mean peak torque with increased knee flexor velocities before training (P<.05). 2.There was no significant differences between the two groups in the H/Q ratio, and no relative increases with increased knee flexor velocities before training. 3. there were significant changes in mean peak torque in group A after training(P<.05), but no significant differences as the velocity increased 4.there were significant changes in mean peak torque in group B after training(P<.05), but no significant differences as the velocity increased 5.there were no significant differences between the two groups, and no significant differences in mean peak torque increase rate between the groups with increased knee flexor velocities after training 6.H/Q ratio increased with increased knee flexor velocities between the two groups, but not statistically And there was no significant differences between the groups with increased knee flexor velocities 7.After training, Ambulation time and its decreasing rate decreased significantly in group B (P<.05) 8Before and after training, there was no significant differences between the groups in the fatiguability 9. In the multiple regression analysis, mean peak torque increase rate of the knee extensor and flexor were higher in group B than A(P<.05), and significantly higher with increased knee flexor velocities (P<.05) Also, training method influenced on Ambulation times decreases significantly(P<.05). Results indicated that knee flexor isokinetic training was effective to knee extensor and flexor mean peak torque increase in the hemiplegia able to walk independently for more than 10 meters. Therefore, we were able to conclude that gradual training from low to high velocity was more effective in the increase of mean peak torque of knee joint and decrease of Ambulation times than training only at high velocity.

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Fluidization Study in the Fluidized Bed Drying of Naked and Husked Barley (쌀보리와 겉보리의 유동층 건조에서의 유동화 연구)

  • Kim, Hee-Yun;Hur, Jong-Hwa;Cho, Duk-Jae
    • Korean Journal of Food Science and Technology
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    • v.24 no.5
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    • pp.414-422
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    • 1992
  • To keep up with urgent need of continuous, effective and rapid drying unit, a fluidized bed drying system with computer controlling air temperature, velocity and relative humidity was designed. This study was attempted to determine physical properties and some basic experiments of fluidized bed d교ing of barley. Also experimental data of the designed fluidized bed drying system using the barely were compared with those of published equations to confirm the reliability of the system and the following results were obtained. The physical dimension husked barley were shown larger than that of naked barley from the experiment. When air temperature. relative humidity and charged amount were $35^{\circ}C$, 30% and 300g respectively, the minimum fluidization velocity of naked and husked barley were found 1.5 m/s and 1.7 m/s. And the optimum fluidization velocity was shown as 3.0 m/s from the experiment. The empirical equation of $U_{mf}$ in this fluidized system was obtained as follow; $U_{mf}^2= \frac{{\phi_s}\;d_p}{Hk}\;{\cdot}\;\frac{(\rho_s-\rho_g)g\;{{\varepsilon}_{mf}^3}} {\rho_g}(Re_p>1,000)$ Where HK=0.4881 for naked barley, 0.6649 for husked barley.

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Development of Car Following Model of Adaptive Cruise Controlled Vehicle Considering Human Factors (인간공학적 요소를 반영한 첨단차량 추종모형)

  • Park, Hee-Je;Bae, Sang-Hoon;Jung, Hee-Jin
    • Journal of Korean Society of Transportation
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    • v.26 no.2
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    • pp.121-133
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    • 2008
  • Conventional car following models are controlled when the velocity of following vehicle is equal to preceding vehicle without consideration of relative distance. Also, since the car following models are hardly consider the driver's behaviors and the environmental factors in driving, the models can't be adopted in reality. Hence, we developed the car following model applying Human Factors to consider driver's safety and comfortness. We simulated to compare the suggested model with the existing model, GGM(General GM). As results of simulations, the GGM model followed the preceding vehicle when the velocity of following vehicle was equal to preceding vehicle without relation of relative range. The other side, when the relative range was less or over than safety range, the suggested model made the relative range equal to safety range. Accordingly, we could be sure that the model would decrease the driver's discomfort and intensify the safety on driving without unnecessary waste of road. We identified that the suggested model is more realistic than the conventional GGM model.

Comfort Properties of Ski Wear Using Vapor-Permeable Water Repellent Fabrics and Thermal Insulation Battings (투습발수직물과 축열보온섬유를 이용한 스키웨어의 쾌적감)

  • Cho Gil Soo;Choi Jong Myoung;Lee Jung Ju;Lee Sern Woo
    • Journal of the Korean Society of Clothing and Textiles
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    • v.16 no.2
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    • pp.245-254
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    • 1992
  • The purpose of this study was to evaluate the mechanical thermal resistances and comfort properties of ski wear made with vapor-permeable water repellent (VPWR) fabrics and thermal insulation battings. Four types of experimental clothing were made with the combination of two VPWR fabrics (Hipora-$TM^{\circledR}$, Hipora-$CR^{\circledR}$) and two thermal insulation battings ($Viwarm^{\circledR},\;Airseal^{\circledR}$). Thermal resistances of ski wear were objectly evaluated by thermal manikin experiment ($21{\pm}\;2^{\circ}C,\;50{\pm}5\%$ R.H.,0.25 m/sec air velocity) and thermographic accessment ($2{\pm}2^{\circ}C,\;0\%$ R.H.,0.25 m/sec air velocity, and emissivity level : 1). Garment wear tests of ski wear included the measurement of the microclimate (inner temp. and relative humidity) of the experimental clothing by digital thermohygrometer and subject wear sensation using McNall's thermal comfort ratings. CBo values of experimental clothing 4 (Hipora-$CR^{\circledR}+Airseal^{\circledR}$) and 1 (Hipora-$TM^{\circledR}+Viwarm^{\circledR}$) were significantly higher than those of 2 (Hipora-$TM^{\circledR}+Airseal^{\circledR}$) and 3 (Hipora-$CR^{\circledR}+Viwarm^{\circledR}$). Thermal resistances in the points of breast, back, belly, and loin was significantly higher than those of upper am, fore arm, and shank of measuring points on the thermal manikin. According to the color map of the thermogram, the experimental clothing 4 indicated higher surface temperatures than the others showing more yellowish spots on the surface of clothing. Inner temperature of experimental clothing was not significantly different among the four types of ski wear, but relative humidities of experimental clothing were significantly different. Relative humidities of experimental clothing 1 and 3 showed higher than those of 2 and 4. Relative humidity of experimantal clothing was affected largely by the thermal resis- tance of thermal insulation batting materials. The subject wear sensation of experimental clothing 2 and 4 showed lower humidity than the others. Subject wear sensation was affected more by humidity sensation than by thermal sensation.

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Estimation of Safety Area for Intercept Debris by Using Modeling and Simulation (탄도탄 요격시험 안전구역 산출을 위한 모델링 및 시뮬레이션)

  • Lee, Sungkyun;Go, Jinyong;Han, Yongsu;Kim, Changhwan
    • Journal of the Korea Society for Simulation
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    • v.29 no.1
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    • pp.1-9
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    • 2020
  • The ballistic missile threat continues to increase with the proliferation of missile technology. In response to this threat, many kinds of interceptors have been emphasized over the years. For development of interceptor, systematic flight tests are essential. Flight tests provide valuable data that can be used to verify performance and confirm the technological progress of ballistic missile defense system including interceptor. However, during flight tests, civilians near the test region could be risk due to a lot of intercept debris. For this reason, reliable estimate of safety area for the flight tests should be preceded. In this study, prediction of safety area is performed through modeling and simulation. Firstly, behaviors of ballistic missile and interceptor are simulated for those entire phase including interception to obtain the relative intercept velocity and the relative impact angle. By using obtained data of kinetic energy, the fragment ejection velocity is calculated and fragment trajectories are simulated by considering drag, gravity and wind effects. Based on the debris field formation and hazard evaluation of debris, final safety area is calculated.

Reduction of a Numerical Grid Dependency in High-pressure Diesel Injection Simulation Using the Lagrangian-Eulerian CFD Method (Lagrangian-Eulerian 기법을 이용한 고압 디젤 분무 시뮬레이션의 수치해석격자 의존성 저감에 관한 연구)

  • Kim, Sa-Yop;Oh, Yun-Jung;Park, Sung-Wook;Lee, Chang-Sik
    • Transactions of the Korean Society of Automotive Engineers
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    • v.20 no.1
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    • pp.39-45
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    • 2012
  • In the standard CFD code, Lagrangian-Eulerian method is very popular to simulate the liquid spray penetrating into gaseous phase. Though this method can give a simple solution and low computational cost, it have been reported that the Lagrangian spray models have numerical grid dependency, resulting in serious numerical errors. Many researches have shown the grid dependency arise from two sources. The first is due to unaccurate prediction of the droplet-gas relative velocity, and the second is that the probability of binary droplet collision is dependent on the grid resolution. In order to solve the grid dependency problem, the improved spray models are implemented in the KIVA-3V code in this study. For reducing the errors in predicting the relative velocity, the momentum gain from the gaseous phase to liquid particles were resolved according to the gas-jet theory. In addition, the advanced algorithm of the droplet collision modeling which surmounts the grid dependency problem was applied. Then, in order to validate the improved spray model, the computation is compared to the experimental results. By simultaneously regarding the momentum coupling and the droplet collision modeling, successful reduction of the numerical grid dependency could be accomplished in the simulation of the high-pressure injection diesel spray.

Deploy Position Determination for Accurate Parachute Landing of a UAV (무인기의 정밀 낙하산 착륙을 위한 전개지점 결정)

  • Kim, Inhan;Park, Sanghyuk;Park, Woosung;Ryoo, Chang-Kyung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.41 no.6
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    • pp.465-472
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    • 2013
  • In this paper, we suggest how to determine the parachute deploy position for accurate landing of a UAV at a desired position. The 9-DOF dynamic modeling of UAV-parachute system is required to construct the proposed algorithm based on neural network nonlinear function approximation technique. The input and output data sets to train the neural network are obtained from simulation results using UAV-parachute 9-DOF model. The input data consist of the deploy position, UAV's velocity, and wind velocity. The output data consist of the cross range and down range of landing positions. So we predict the relative landing position from the current UAV position. The deploy position is then determined through distance compensations for the relative landing positions from the desired landing position. The deploy position is consistently calculated and updated.

Measurement of Black Carbon Concentration in Rural Area (교외지역 블랙카본 농도 측정)

  • Lee, Ki Woong;Han, Seung Cheol;Lee, Jeonghoon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.38 no.1
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    • pp.17-24
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    • 2014
  • We measured black carbon concentration in rural area to understand the characteristic of atmospheric aerosol by comparing the black carbon concentration and meteorological factors such as PM10 concentration, relative humidity, temperature and wind velocity. A MAAP (Multi Angle Absorption Photometer) which is one of filter based equipments was used to measure black carbon concentration. Black carbon concentration was measured to be high from April to May and low from June to September. Black carbon concentration was proportional to PM10 concentration. Black carbon concentration was correlated to relative humidity. Black carbon concentration was inversely proportional to wind velocity and temperature. Finally, we suggest that the volume fraction of black carbon in the atmosphere can be estimated from the size, number concentration and absorption coefficient measured using the MAAP.

An Analysis of three-dimensional collision probability according to approaching objects to the KOMPSAT series (아리랑 위성들의 경향에 따른 및 3차원 충돌확률 분석)

  • Seong, Jae-Dong;Kim, Hae-Dong;Lim, Seong-Min
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.41 no.2
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    • pp.156-163
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    • 2013
  • Collision probability is the most common method to measure the risk of space debris, it is widely used that two dimensional linear collision probability using the closest approach distance. This paper represents the characteristics of object that approach KOMPSAT 2, 3, 5 that have operated or will be operated by Korea. And more precise method than two dimensional linear collision probability, we analyzed the properties of three dimensional nonlinear collision probability using STK/Nonlinear Collision Probability Tool. Through this, efficiency of three dimensional nonlinear collision probability for KOMPSAT series satellites was investigated. The result represents that three dimensional nonlinear collision probability showed the precise outcome at a relative velocity of less than 350m/s. Also, KOMPSAT series satellites appeared to few low relative velocity approaches and showed low efficiency for the three dimensional nonlinear collision probability.