• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.10 s.253
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• pp.1276-1283
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• 2006

This study proposes two ESP systems which are designed to enhance the lateral stability of a vehicle. A BESP uses an inner rear wheel braking pressure controller, while a EBESP employs an inner rear wheel and front outer wheel braking pressure controller. The performances of the BESP and EBESP are evaluated for various road conditions and steering inputs. They reduce the slip angle and eliminate variation in the lateral acceleration, which increase the controllability and stability of the vehicle. However EBESP enhances the lateral stability and comfort. A driver model is also developed to control the steer angle input. It shows good performances because the vehicle tracks the desired lane very well.

• Smart Structures and Systems
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• v.22 no.3
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• pp.335-340
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• 2018

The behavior of concrete slabs in composite beam with C and L shaped angle shear connectors has been studied in this paper. These two types of angle shear connectors' instalment have been commonly utilized. In this study, the finite element (FE) analysis and soft computing method have been used both to present the shear connectors' push out tests and providing data results used later in soft computing method. The current study has been performed to present the aforementioned shear connectors' behavior based on the variable factors aiming the study of diverse factors' effects on C and L shaped angle in shear connectors. ANFIS (Adaptive Neuro Fuzzy Inference System), has been manipulated in providing the effective parameters in shear strength forecasting by providing input-data comprising: height, length, thickness of shear connectors together with concrete strength and the respective slip of shear connectors. ANFIS has been also used to identify the predominant parameters influencing the shear strength forecast in C and L formed angle shear connectors.

• Journal of Acupuncture Research
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• v.18 no.3
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• pp.215-226
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• 2001

Objective : Spondylolisthesis has become one of the major causes of the lower back pain in the orthopedic field. We wanted to compare the radiological change with before & after treatment including constitution-acupuncture on spondylolisthesis. Methods : This study were carried out on 9 patients with spondylolisthesis. We reviewed medical records and radiological films. We studied rating score, percent of slip, sagittal angle, percent of posterior disc height. Results and conclusions : The improvement index showed 0.04, 030, 033, 0.00, 0.32 points in isthmic type, and 0.55, 0.56, 0.53, 0.00 points in degenerative type. The percent of slip for pre/post-treatment showed 20/20, 12/11, 24/20, 30/30, 4/3 percents in isthmic type, and 12/4, 16/11, 13/9, 8/8 percents in degenerative type. Sagittal angle showed 11/11, 15/12, 21/18, 17/15, 21.19 degrees in isthmic type, and 22/21, 19/15, 2/2, 8/9 degrees in degenerative type. Percent of posterior disc height were 17/18, 26/28, 24/25, 22/23, 25/27 in isthmic type, and 29/33, 37/45, 25/31, 24/24 in degenerative type. The result suggest that constitution-acupuncture and conservational treatment are good method for treatment of spondylolisthesis, and especially in degenerative type.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.1
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• pp.41-48
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• 2014

A urea-SCR system suffers from some issues associated with the ammonia slip phenomenon, which mainly occurs because of the shortage of evaporation and thermolysis time, and this makes it difficult to achieve an uniform distribution of injected urea. A numerical study was therefore performed by changing such various parameters as installed injector angle and application and angle of mixer to enhance evaporation and the mixing of urea water solution with exhaust gases. As a result, various parameters were found to affect the evaporation and mixing characteristics between exhaust gas and urea water solution, and their optimization is required. Finally, useful guidelines were suggested to achieve the optimum design of a urea-SCR injection system for improving the DeNOx performance and reducing ammonia slip.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.3
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• pp.29-37
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• 2000

In this paper, the thrust control of PWM Inverter-fed SLIM(Single-sided Linear Induction Motor) is achieved by vector control and PID control with DSP(TMS320C32). SLIM which used as a conveyor has required the quick response and the constant operating without air gap trembling while it conveys load.Thus, SLIM should have the smallest trembling of air gap length. First, voltage equations for SLIM are calculated from the proposed equivalent circuit in this peper, and not only the exciting current but also the thrust component are obtained from them. The thrust current ripple can be reduced by the vector controller using a slip angle frequency, and the PID controller is also use for the position control.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.8
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• pp.1716-1721
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• 2005

Conventionally, 2WS is used for vehicle sleeting, which can only steering front wheel. In case of trying to high speed slalom or emergency through this kind of vehicle equipped 2WS, it may occur much of side slip angle. On the other hand, 4WS makes decreasing of side slip angle, outstandingly, so it is possible to support vehicle movement stable. And conventional ABS and TCS can only possible control the longitudinal movement of braking equipment and drive which can only availab to control of longitudinal direction. There after new braking system ESP was developed, which controls both of longitudinal and lateral, with adding of the function of controlling Active Yaw Moment. On this paper, we show about not only designing of improed braking and steering system through establishing of the integrated control system design of 4WS and ESP but also designing of the system contribute to precautious for advanced vehicle stability problem.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3158-3163
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• 2013

In this study, squeal noise test was conducted by using the lab-scaled brake dynamometer. Squeal conditions with respect to the angle of the brake pads ($34^{\circ}30^{\circ}26^{\circ}$) and negative slope, were studied. Squeal frequency of the In-plane-like mode was confirmed by hammering test and finite element analysis. This Squeal mode was difficult to control by the pad angle variation. Also the squeal sound was found to be periodic signal which has higher harmonic components. Squeal noise is independent of the negative slope. It implies that squeal noise can reach the stick-slip oscillation.

• Journal of Electrical Engineering and Technology
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• v.3 no.1
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• pp.79-87
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• 2008

This paper proposes the design and implementation of a direct torque controlled induction motor drive system. The method is based on control of decoupling between amplitude and angle of reference stator flux for determining reference stator voltage vector in generating PWM output voltage for induction motors. The objective is to reduce electromagnetic torque ripple and stator flux droop which result in a decrease in current distortion in steady state condition. In addition, the proposed technique provides simplicity of a control system. The direct torque control is based on the relationship between instantaneous slip angular frequency and rotor angular frequency in adjustment of the reference stator flux angle. The amplitude of the reference stator flux is always kept constant at rated value. Experimental results are illustrated in this paper confirming the capability of the proposed system in regards to such issues as torque and stator flux response, stator phase current distortion both in dynamic and steady state with load variation, and low speed operation.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.12
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• pp.117-122
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• 2009

The hexagonal network-type PDMS microstructures were fabricated and they were employed to low-friction drag surfaces. While the lowest contact angle measured from the smooth surface was $108^{\circ}$ the highest contact angle measured from the microstructured surfaces was $145^{\circ}$ The moving speed of bullet-type capsule attached with a PDMS pad of smooth surface ($CA=108^{\circ}$) was 0.1261 m/s and that with a PDMS pad of microstructured surface ($CA=145^{\circ}$) was 0.1464 m/s. Compared with the smooth surface, the microstructured surface showed 16.1% higher moving speed. The network-type microstructures have a composite surface that is composed with air and PDMS solid. Therefore, the surface does not wet: rather water is lifted by the microstructures. Because of the composite surface, water shows slip-flow on the microstructures, and thus friction drag can be reduced.

• Journal of Biosystems Engineering
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• v.26 no.4
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• pp.337-354
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• 2001

This study was conducted in order to develop a Chinese cabbage harvester attachable to tractors. For designing Chinese cabbage harvester in which laboratory and field tests were conducted with to determine feasible values design factors. To adopt the various sizer of C-cabbages, U-type soft rubber band was attached to the chain conveyor with an angle. Required torque of the conveyor axle was about 206-210kgf$.$cm. And the required peripheral speed of the disk cutter was 6.54m/s or more to have a clean session in root cutting. Three different harvest method were tested. The best harvesting method with minimum pulling force and damage was disk cutting flying just above the soil surface were the cut chinese cabbages are transferring to the holding conveyor attached soft rubber lug in prompt. Theoretical speed ratio of the tractor travel and feed of a chain conveyor was 1:1.2 with the attaching angle of 30 degree and 1:1.1 with the angle of 20 degree. Actual field experiment showed the speed ratio of 1:1.5 was the best because of the slip effect.