• Journal of Distribution Science
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• v.13 no.3
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• pp.61-67
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• 2015

Purpose - Exports have long been regarded as significant drivers of sustainable competitive advantage and growth among small and medium enterprises (SMEs). The export activities of SMEs are particularly important in the context of export-oriented economies such as Korea. Although many studies have examined the determinants of exports, it is difficult to find empirical studies about the determinants of the export performance of regional SMEs. This study investigates the determinants of export performance in the regional SME context based on an integrated approach that combines the environment factor of industrial organization theory, competitive strategy theory, and the competences of the resource-based view. Research design, data, and methodology - To empirically analyze the determinants of export performance in the regional SMEs, data were collected from firms in the Daegu metropolitan area. Data were collected directly through questionnaire surveys; in addition, secondary financial data were also taken from the KIS-VALUE database. Out of the 175 responses that were received, 143 were considered to be worth examining. After testing the reliability and validity of the variables through multiple items such as environmental turbulence and competitive strategy, hypotheses were verified by using five multi-regression models. These models were: a control model with organizational size and age, an environmental model with technology and market turbulence, a competency model with R&D and foreign distribution channels, a strategy model with product and market differentiation, and an integrated model including all of these variables. Results - First, as a control variable, the organization size has significant positive effects on export performance. Second, technology turbulence based on industrial organization theory has significant positive effects on export performance, but market turbulence does not affect export performance. Third, the foreign market distribution competency of the resource-based view has strong positive effects on export performance, but the R&D competency does not affect export performance. Fourth, the product differentiation strategy from competitive strategy theory positively impacts export performance, but market differentiation does not affect export performance. Finally, in the integrated model, only the foreign distribution competency of the resource-based view has a significant effect on export performance. Conclusions - The empirical results of this study verified the usefulness of the rationales behind the three theories to explain the export performance of the regional SMEs, especially the importance of the foreign market distribution competency from the resource-based view. With regard to practical considerations, this study's implications suggest that the use of technological environmental changes by industries is better than the use of market changes. Further, the use of the product differentiation strategy is more effective than the use of the market-driving strategy, and the distribution channel competency plays a stronger role than the technology-oriented competency with regard to the export performance position of regional SMEs. Future studies should examine relational perspectives, such as trust among channel partners. Therefore, the configuration approach is more useful in enhancing pragmatism by comparing high- and low-export companies.

• Journal of the Korean Chemical Society
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• v.44 no.6
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• pp.600-610
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• 2000

The purpose of this study was to design the new teaching strategy based on the particulate model facilitating the reflective thinking (RE-PM) in the learning of the particulate nature of matter, and to investigate the effect of the new teaching strategy in compare with the traditional teaching strategy (TS-PM) after treating with new teaching strategy on preliminary teachers of elementary school. The problems of traditional teaching strategy are as follows: 1) Most of students didn't think the particulate model connected with practical material. 2) Most of students have a tendency of the rote memory on learning of the traditional particulate model. 3) The ratio of changing the view of continuous matter into the view of particulate nature of matter was very low, after learning the particulate model using of the traditional teaching strategy. The new teaching strategy facilitating the reflective thinking was more effective on the understanding of particulate nature of matter and the driving of motivation than the traditional teaching strategy in the learning of the particulate nature of matter.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.1
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• pp.17-24
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• 2011

TMED(Transmission Mounted Electric Device) parallel hybrid configuration can realize EV(Electric Vehicle) mode by disengaging the clutch between an engine and a transmission-mounted motor to improve efficiencies of low load driving and regenerative braking. In the EV mode, however, jerk can be induced since there are insufficient damping elements in the drive-train. Though the jerk gives demoralizing influence upon driving comport, adding a physical damper is not applicable due to constraints of the layout. This study suggests the jerk reduction control, composed of active damping method and torque profiling method, to suppress the jerk without hardware modification. The former method creates a virtual damper by generating absorbing torque in the opposite direction of the oscillation. The latter method reduces impulse on the mated gear teeth of the drive-train by limiting the gradient of traction torque when the direction of the torque is reversed. To validate the effectiveness of the suggested strategy, a series of vehicle tests are carried out and it is observed that the amplitude of the oscillation can be reduced by up to 83%.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.6
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• pp.3086-3103
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• 2017

Video images captured by vehicle cameras often contain blurry or dithering frames due to inadvertent motion from bumps in the road or by insufficient illumination during the morning or evening, which greatly reduces the perception of objects expression and recognition from the records. Therefore, a real-time electronic stabilization method to correct fuzzy video from driving recorders has been proposed. In the first stage of feature detection, a coarse-to-fine inspection policy and a scale nonlinear diffusion filter are proposed to provide more accurate keypoints. Second, a new antiblurry binary descriptor and a feature point selection strategy for unintentional estimation are proposed, which brought more discriminative power. In addition, a new evaluation criterion for affine region detectors is presented based on the percentage interval of repeatability. The experiments show that the proposed method exhibits improvement in detecting blurry corner points. Moreover, it improves the performance of the algorithm and guarantees high processing speed at the same time.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.620-622
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• 2004

Mobility of an indoor wheeled robot is affected by adhesion force that is related to various floor conditions. When the adhesion force between driving wheels and the floor decreases suddenly, the robot has a slip state. In order to overcome this slip problem, optimal slip velocity must be decided for stable movement of wheeled robot. First of all, this paper shows that conventional PI control can not be applied to a wheeled robot of the light weigh. Secondly, reposed fuzzy logic applied by the Takagi-Sugeno model for the configuration of fuzzy sets. For the design of Takaki-Sugeno model and fuzzy rule, proposed algorithm uses FCM(Fuzzy c-mean clustering method) algorithm. In additionally, this algorithm controls recovered driving torque for the restrain the re-slip. The proposed fuzzy logic controller(FLC) is pretty useful with prevention of the slip phenomena through that compare fuzzy with PI control for the controller performance in the re-adhesion control strategy. These procedures are implemented using a Pioneer 2-DXE wheeled robot parameter.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.464-469
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• 2001

This work provides the biomechanical evaluations of a manual wheelchair with a bi-directional driving system. The new propulsion strategy can be accomplished by employing a special gear system that converts the oscillatory motion of a handrim into the unidirectional output motion of a wheel. A main feature of the forward. backward propulsion is to supply continuous driving torque without break. Motion. analysis has been performed through 2-dimensional image processing for measuring the kinematic properties of the upper arm and fore arm. Then, the inverse dynamics analysis has been done for obtaining the joint torques, the handrim forces and input/output powers. Results show that the output power by the forward. reverse propulsion is almost twice as much as that by conventional propulsion. Also, the new propulsion is expected to reduce the fatigues and injuries at arm joints by employing more muscle groups for movement. In conclusion, the forward. reverse propulsion can greatly improve the performances of manual wheelchairs by providing better mobility as well as by guaranteeing several advantages from a biomechanical viewpoint. Future development of a manual wheelchair optimized for the bi-directional propulsion will further improve the propulsion performances.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.23 no.1
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• pp.7-14
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• 2014

The core of the automotive industry's strategy to handle the climate change can be explained as the development and distribution of the vehicles with high fuel efficiencies and low emission. Clean Diesel, hydrogen fuel cell, electric, and especially hybrid power-train vehicles have been actively studied. This paper dynamically analyzes the performance of a hybrid system's five driving modes. The research subject consists of one engine, two electric motors, two simple planetary gears, and one compound planetary gears with five clutches. To define the steady state equation of the system, interaction formulas of five driving modes are introduced with motion variables and torque variables. These formulas are then used to analyze the speeds, torques, and power flows of each mode.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.8 s.227
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• pp.1125-1134
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• 2004

This paper presents a mathematical model which is about the dynamics of not only a two wheel steering vehicle but a four wheel steering vehicle. A sliding mode ABS control strategy and PID rear wheel control logic are developed to improve the brake and cornering performances, and enhance the stability during emergency maneuvers. The performances of the controllers are evaluated under the various driving road conditions and driving situations. The numerical study shows that the proposed full car model is sufficient to accurately predict the vehicle response. The proposed ABS controller reduces the stopping distance and increases the vehicle stability. The results also prove that the ABS controller can be employed to a four wheel steering vehicle and improves its performance. The four wheel steering vehicle with PID rear wheel controller shows increase of stability when a vehicle speed is high and sharp cornering maneuver when a vehicle speed is low compared to that of a two wheel steer vehicle.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.7
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• pp.646-654
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• 2010

This paper describes an integrated chassis control for a maneuverability, a lateral stability and a rollover prevention of a vehicle by the using of the ESC and AFS. The integrated chassis control system consists of a supervisor, control algorithms and a coordinator. From the measured and estimation signals, the supervisor determines the vehicle driving situation about the lateral stability and rollover prevention. The control algorithms determine a desired yaw moment for lateral stability and a desired longitudinal force for the rollover prevention. In order to apply the control inputs, the coordinator determines a brake and active front steering inputs optimally based on the current status of the subject vehicle. To improve the reliability and to reduce the operating load of the proposed control algorithms, a multi-core ECU platform is used in this system. For the evaluation of this system, a closed loop simulations with driver-vehicle-controller system were conducted to investigate the performance of the proposed control strategy.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.1
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• pp.99-111
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• 2016

This paper presents an integrated fault diagnosis algorithm for driving motor of In-wheel independent drive electric vehicle. Especially, this paper proposes a method that integrated the high level fault diagnosis and the low level fault diagnosis in order to improve a robustness and performance of the fault diagnosis system. The high level fault diagnosis is performed using the vehicle dynamics analysis and the low level fault diagnosis is carried using the motor system analysis. The validity of the high level fault diagnosis algorithms was verified through $Carsim^{(R)}$ and MATLAB/$Simulink^{(R)}$ cosimulation and the low level fault diagnosis's validity was shown by applying it to a MATLAB/$Simulink^{(R)}$ interior permanent magnet synchronous motor control system. Finally, this paper presents a fault diagnosis strategy by combining the high level fault diagnosis and the low level fault diagnosis.