• 한국신재생에너지학회:학술대회논문집
• /
• 2006.06a
• /
• pp.547-550
• /
• 2006

The power split hybrid power train is considered to be one of the most prospective configuration for the hybrid electric vehicle (HEV). Toyota Prius, representing this type of vehicle, showed outstanding performances in fuel efficiency, emission reduction and acceleration. The excellence is largely due to the fact that it utilizes almost all operation modes of HEV. Those modes include ZEV (Zero Emission Vehicle) driving, idle stop, fuel cut-off, power assist, active charging, regenerative braking and so forth. In this paper, a few of the mode operations were simulated using AVL Cruise. Also, control logics to operate the powertrain in each mode were developed. The states of powertrain components were displayed and analyzed. By controlling the three components (engine, motor and generator), it was possible to run the powertrain in several hybrid operation modes.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.6 no.6
• /
• pp.873-880
• /
• 2011

As environmental pollution, global warming, and exhaustion of fossil fuel become global issue recently, there has been strong research motivation to develop green energy technology. Along the same line of motivation, some research efforts have been put into the development of environment-friendly bicycle equipped with various smart energy technologies to increase the usability of the bicycle as short-distance transportation. Among the technologies related with new generation bicycle, PAS (power assist system) is one of the most important systems that are essential in efficiently integrating human power and the electrical power supplied by electric motor driven by battery. In this paper, a novel torque sensor technology which is core component for PAS is proposed. Unlike existing technologies, strain gauges are attached to rear shaft directly under the hub bearings, which eliminates the requirement of slip-ring, Furthermore, the sensor is able to not only measure the torque transmitted to driving axle by human but also estimate the position of the gear to which the chain is currently engaged.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.39 no.2
• /
• pp.211-217
• /
• 2015

Emission gas regulations and constantly increasing fuel costs call for the worldwide use of environmentally friendly and energy-efficient machines in industry. To meet these requirements, a hybrid excavator prototype has been developed that incorporates an electric swing motor, engine assist motor, and ultra-capacitor module into a conventional hydraulic excavator of the 22-ton class. This paper mainly describes a few techniques to optimize its energy efficiency. These include 1) controlling the engine speed in proportion to the load torque, 2) controlling the pump displacement when driving the electric swing system, 3) managing the ultra-capacitor voltage to minimize the electrical energy loss, and 4) reducing the cooling fan speed to improve the energy efficiency of the system.

• Physical Therapy Rehabilitation Science
• /
• v.8 no.2
• /
• pp.93-98
• /
• 2019

Objective: The purpose of this study was to investigate the effect of robot arm reach training on upper extremity functional movement in chronic stroke survivors. Design: One group pretest-posttest design. Methods: Thirteen chronic stroke survivors participated in this study. Robot arm reach training was performed with a Whole Arm Manipulator (WAM) and a 120-inch projective display to provide visual and auditory feedback. During the robotic arm reach training, WAM provided gravity compensation and assist-as-needed (AAN) force according to the robot control mode. When a participant could not move the arm toward the target for more than 2 seconds, WAM provided AAN force to reach the desired targets. All patients participated in the training for 40 minutes per day, 3 times a week, for 4 weeks. Main outcome measures were the Fugl-Meyer Assessment (FMA), Action Research Arm Test (ARAT) and Box and Block Test (BBT) to assess upper extremity functional movement. Results: After 4 weeks, significant improvement was observed in upper extremity functional movement (FMA: 42.15 to 46.23, BBT: 12.23 to 14.00, p<0.05). In the subscore analysis of the FMA upper extremity motor function domains, significant improvement was observed in upper extremity and coordination/speed units (p<0.05). However, there were no significant differences in the ARAT. Conclusions: This study showed the positive effects of robot arm reach training on upper extremity functional movement in chronic stroke survivors. In particular, we confirmed that robot arm reach training could have a positive influence by leading to improvement of motor recovery of the proximal upper extremity.

• Clinical and Experimental Pediatrics
• /
• v.63 no.3
• /
• pp.88-95
• /
• 2020

Accurate localization of the seizure onset zone is important for better seizure outcomes and preventing deficits following epilepsy surgery. Recent advances in neuroimaging techniques have increased our understanding of the underlying etiology and improved our ability to noninvasively identify the seizure onset zone. Using epilepsy-specific magnetic resonance imaging (MRI) protocols, structural MRI allows better detection of the seizure onset zone, particularly when it is interpreted by experienced neuroradiologists. Ultra-high-field imaging and postprocessing analysis with automated machine learning algorithms can detect subtle structural abnormalities in MRI-negative patients. Tractography derived from diffusion tensor imaging can delineate white matter connections associated with epilepsy or eloquent function, thus, preventing deficits after epilepsy surgery. Arterial spin-labeling perfusion MRI, simultaneous electroencephalography (EEG)-functional MRI (fMRI), and magnetoencephalography (MEG) are noinvasive imaging modalities that can be used to localize the epileptogenic foci and assist in planning epilepsy surgery with positron emission tomography, ictal single-photon emission computed tomography, and intracranial EEG monitoring. MEG and fMRI can localize and lateralize the area of the cortex that is essential for language, motor, and memory function and identify its relationship with planned surgical resection sites to reduce the risk of neurological impairments. These advanced structural and functional imaging modalities can be combined with postprocessing methods to better understand the epileptic network and obtain valuable clinical information for predicting long-term outcomes in pediatric epilepsy.

• Journal of the Korean Society of Physical Medicine
• /
• v.4 no.3
• /
• pp.183-192
• /
• 2009

Purpose：This study was conducted to investigate whether modified CIMT with Kinesio-Taping on paretic upper limb effects upper limb function in stroke patients in comparison to those receiving only modified CIMT. Methods：20 out-patients with hemiplegia were randomly assigned to either an experimental or a control group. Both groups received modified CIMT during a 10-week period. Additionally, an experimental group received modified CIMT with Kinesio-Taping on paretic upper limb and trunk. Results：In Manual function test, Grip strength, Jebsen-Taylor hand function test, MAL(Motor Activity Log) and Functional independence measure (FIM) were significantly different at all intervals of the study period(0, 3, 6, 10-week) in the experimental and control groups(p<.05). Exceptionally there was no significant difference in Jebsen-Taylor hand function test between the experimental and control groups. Conclusion：These results suggest that modified CIMT with Kinesio-taping improve the upper limb function. And also increase usage of affected upper limb and assist in daily living activity more than only modified CIMT.

• Journal of Energy Engineering
• /
• v.21 no.1
• /
• pp.86-108
• /
• 2012

$CO_2$ reduction, energy security, and emission reduction are the critical issues in the current automotive industry. As one of the solutions to these issues, Battery Electric Vehicle is attracting attention recently. Advanced battery electric drive vehicle require batteries, power electronics and electrical machines to function. These devices allow the vehicle to use energy from the battery to assist in the propulsion of the vehicle. In this paper, the main feature of these technologies are briefly introduced and recent trends of patent applications are described.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.868-869
• /
• 2011

Domestic Foreign automaker's are focused on the high-efficiency, low emission cars development. On the way, the hybrid car is the first priority. Hybrid electric vehicle battery pack configurations, EV Relay one of the key components of the engine driving, to assist in the drive motor to supply electrical energy to the battery is a device for opening and closing of the output device. EV Relay determine the longevity and the replacement cycle, The EV Relay environmental conditions and duty cycle considering the reliability tests are essential requirements of many automotive companies to respond to RFQ, this test is essential. This paper using Maxwell Software for Prediction of the Ev Relay impulse, the theoretical data to obtain the impulse to develop methods for mechanical testing after to take advantage of it.

• Journal of Electrical Engineering and Technology
• /
• v.10 no.6
• /
• pp.2376-2383
• /
• 2015

Assistance of the operator’s walking ability while carrying a load is a challenging area in lower limb exoskeletons. We implement an exoskeleton called the Unmanned Technology Research Center Exoskeleton (UTRCEXO), which enables the operator to walk with a load more comfortably. The UTRCEXO makes use of two types of DC motor to assist the hip and knee joints. The UTRCEXO detects the operator’s walking intention including step initiation with insole-type FSRs faster without using any bio-signals and precedes the operator’s step with a reference torque. It not only reduces interaction forces between the operator and the UTRCEXO, but also allows the operator to walk with a load more comfortably. In this paper, we present the UTRCEXO implementing the walking assistance mechanism with interaction force reduction during walking.

• Journal of Mechanical Science and Technology
• /
• v.19 no.3
• /
• pp.792-801
• /
• 2005

This paper discusses a dc motor equipped electric power steering (EPS) system and demonstrates its advantages over a typical hydraulic power steering (HPS) system. The tire-road interaction torque at the steering tires is calculated using the 2 d.o.f. bicycle model, in other words by using a single-track model, which was verified with the J-turn test of a real vehicle. Because the detail parameters of a steering system are not easily acquired, a simple system is modeled here. In previous EPS systems, the assisting torque for the measured driving torque is developed as a boost curve similar to that of the HPS system. To improve steering stiffness and return-ability of the steering system, a third-order polynomial as a torque map is introduced and modified within the preferred driving torques researched by Bertollini. Using the torque map modification sufficiently improves the EPS system.