• The Journal of Korean Physical Therapy
• /
• 제27권5호
• /
• pp.364-368
• /
• 2015

Purpose: Walking in the dual-task condition is a critical skill for hemiplegic patients to live in real-life situations. The purpose of this study was to compare the effect of dual-task gait training and general gait training on gait parameters and cognitive function in patients with chronic stroke during dual-task walking. Methods: The study included 23 patients with chronic hemiparetic stroke who were randomly divided into experimental (dual-task gait training) and control (general walking training) groups. The 11 subjects in the experimental group and nine subjects in the control group received dual-task gait training (walking while handling a ball, crossing obstacles, picking up various objects, and problem solving simple cognitive tasks and general over-ground gait training, respectively, for 30 minutes per day 5 days per week for 4 weeks. Spatiotemporal parameters and cognitive tasks in the dual-task gait condition were measured. Statistical analysis of the changes between the pre- and post-intervention measurement variables was performed using ANCOVA. Results: In the gait condition under cognitive tasks, the changes pre- and post-intervention in gait velocity, stride length, double support limb, and step symmetry were significantly greater in the dual-task gait training group; however, the dual-task gait training group showed no significant improvement compared to the general gait training group in terms of the assessment of cognitive tasks. Conclusion: The findings suggest that dual-task gait training may be beneficial for walking ability in dual-task walking condition.

• 한국자동차공학회논문집
• /
• 제8권4호
• /
• pp.169-176
• /
• 2000

Longitudinal and lateral forces acting on tires are known to be closely related to the tract-ability braking characteristics handling stability and maneuverability of ground vehicles. In thie paper in order to develop tire force monitoring systems a monitoring model is proposed utilizing not only the vehicle dynamics but also the roll motion. Based on the monitoring model three monitoring systems are developed to estimate the tire force acting on each tire. Two monitoring systems are designed utilizing the conventional estimation techniques such as SMO(Sliding Mode Observer) and EKF(Extended Kalman Filter). An additional monitoring system is designed based on a new SKFMEC(Scaled Kalman Filter with Model Error Compensator) technique which is developed to improve the performance of EKF method. Tire force estimation performance of the three monitoring systems is compared in the Matlab simulations where true tire force data is generated from a 14 DOF vehicle model with the combined-slip Magic Formula tire model. The built in our Lab. simulation results show that the SKFMEC method gives the best performance when the driving and road conditions are perturbed.

• Journal of Korean Society for Atmospheric Environment
• /
• 제15권E호
• /
• pp.73-79
• /
• 1999

To Characterize the single raindrops as a function of their size we designed the sampling and handling apparatuses. Samplings of single and size- classified raindrops were performed at a height of 20m above the ground level of a Kyoto University building located in Uji, Japan in rain events from middle of July to the end of August, 1999. And PIXE method was applied to the analysis of single raindrops sampled as a function of their size. Diameter change of frozen raindrops by liquid nitrogen did nto affect the size segregation ability of our sampling apparatus. The number of raindrops increases with decreasing drop size. And it is found that the size distribution of raindrops verified depends on the rain events. Application of PIXE analysis to the measurement of single raindrops was very successful. Every element showed a continuous increase in concentration with decreasing raindrop diameter. It seems reasonable to say that our work should be helpful to obtain more detailed information on single raindrops and especially to study on the rainout and washout mechanisms.

• Journal of Mechanical Science and Technology
• /
• 제17권10호
• /
• pp.1450-1457
• /
• 2003

Structural integrity of either a passenger car or a light truck is one of the basic requirements for a full vehicle engineering and development program. The results of the vehicle product performance are measured in terms of durability, noise/vibration/harshness (NVH), crashworthiness and passenger safety. The level of performance of a vehicle directly affects the marketability, profitability and, most importantly, the future of the automobile manufacturer. In this study, we used the Virtual Proving Ground (VPG) approach for obtaining the dynamic stress or strain history and distribution. The VPG uses a nonlinear, dynamic, finite element code (LS-DYNA) which expands the application boundary outside classic linear, static assumptions. The VPG approach also uses realistic boundary conditions of tire/road surface interactions. To verify the predicted dynamic stress and fatigue critical region, a single bump run test, road load simulation, and field test have been performed. The prediction results were compared with experimental results, and the feasibility of the integrated life prediction methodology was verified.

• 동력기계공학회지
• /
• 제19권2호
• /
• pp.15-21
• /
• 2015

Bollard installed on the street is a facility that protects pedestrians by restraining cars from entering on the sidewalk. It is basically classified into manual, semiautomatic, automatic type and mostly manual type is widely used because the automatic type is imported and much expensive. However, in case of manual handling type in practice, it is very troublesome and difficult to remove it whenever cars are permitted, and in case of automatic type, since underbody of a bollard is very long, it is difficult to dig a deep hole in the ground because a pipe, a hose or a cable is under the surface. In order to reduce these difficulties, this paper proposed new design of the multistage bollard that moves up and down automatically by using hydraulic system. This is developed by 6 step creativity of TRIZ inventive problem solving and structural analysis. The developed bollard can be installed in shallow hole and allow entry of vehicles through up-and-down movement without its removal manually. Finally, we could see smoothly motion through the manufactured bollard.

• 대한물리치료과학회지
• /
• 제8권2호
• /
• pp.1059-1064
• /
• 2001

This study is aimed at diagnosing transmutation aspect with the respective of hemiplegia patient's static adaptation of posture which is influenced by anti-gravity excercise, center of gravity shifting movement and segmental movement adaption of the legs and arms by key-point control in the process of Bobatli's treatment approach. The patients for the investigation of this study were selected as a total 17 patients who were doing the physical-therapy in Tae-gu Rehabilitation Center, and diagnosed as hemiplegia patients by Rehabilitation Medicine department in Kyung-buk University hospital. And also, there investigated into temporal transition that keep the attitude with one-leg standing on the ground concerning static attitude adaption on the basis of the before of anti-gravity movement and the after of 4-weeks movement. The findings of this study were as follows: With the respective the time to keep standing pose by one-leg at static attitude transmutation, affected side showed meaningful differences as a l.86/sec, 2.62/sec at 4 weeks later considering the before and after of this experiment.(p<0.01), non-affected side at the aspect of attitude keeping time, but there didn't showed meaningful differences statistically.

• 한국산업융합학회 논문집
• /
• 제23권3호
• /
• pp.481-489
• /
• 2020

Safety and security during the handling of hazardous materials is a great concern for anyone in the field. One driving point in the security field is the ability to detect the source of the danger and take action against it as quickly as possible. Via the usage of a fully convolutional network, it is possible to create the label map of an input image, indicating what object is occupying the specific area of the image. This research employs the usage of U-net, which was constructed in biomedical field segmentation to segment cells, instead of the original FCN. One of the challenges that this research faces is the availability of ground truth with precise labeling for the dataset. Testing the network after training resulted in some images where the network pronounces even better detail than the expected label map. With better detailed label map, the network might be able to produce better segmentation is something to be studied in further research.

• ETRI Journal
• /
• 제36권1호
• /
• pp.116-123
• /
• 2014

In this paper, a novel unequal broadband out-of-phase power divider (PD) is presented. Double-sided parallel-strip lines (DSPSLs) are employed to achieve an out-of-phase response. Also, an asymmetric dual-band matching structure with two external isolation resistors is utilized to obtain arbitrary unequal power division, in which the resistors are directly grounded for heat sinking. A through ground via (TGV), connecting the top and bottom sides of the DSPSLs, is used to short the isolation components. Additionally, this property can efficiently improve the broadband matching and isolation bandwidths. To investigate the proposed divider in detail, a set of design equations are derived based on the circuit theory and transmission line theory. The theoretical analysis shows that broadband responses can be obtained as proper frequency ratios are adopted. To verify the proposed concept, a sample divider with a power division of 2:1 is demonstrated. The measured results exhibit a broad bandwidth from 1.19 GHz to 2.19 GHz (59.2%) with a return loss better than 10 dB and port isolation of 18 dB.

• 소음진동
• /
• 제9권1호
• /
• pp.121-130
• /
• 1999

Generally, A Dynamic Absorber by using Active viscous Damping is highlighted for effective suspension system, such as improved ride comfort and handling in the market. Lately, this system based on the Sky-Hook damper theory is introduced by the name of "Active Dynamic Absorber" to us. This system has an excellent performance in contrast to Passive. Adaptive Dynamic Absorber, besides having low cost components of system, low energy consumption. light weight of system. In this viewpoint. most of car-maker will adopt this system in the near future. For this reason, we developed Dynamic Absorber by using Active viscous Damping which is equipped with continuously variable Dynamic Absorber and Control logic consisting Filter and Estimator. control apparatus of Dynamic Absorber operated by 16-bit microprocessor of high performance. variable device of viscous Damping. G-sensor so on. In this paper. several important points of development procedure for realizing this system will be described with results in which is obtained from experiment by simulation and Full car test in Proving ground. respectively.pectively.

• 대한기계학회논문집A
• /
• 제24권7호
• /
• pp.1871-1877
• /
• 2000

Longitudinal and lateral forces acting at tire are known to be closely related to the tractive ability, braking characteristics, handling stability and maneuverability of ground vehicles. However, it is not feasible in the operating vehicles to measure the tire forces directly because of high cost of sensors, limitations in sensor technology, interference with the tire rotation and harsh environment. In this paper, in order to develop tire force monitoring system, a new vehicle dynamics monitoring model is proposed including the roll motion. Based on the monitoring model, tire force monitoring system is designed to estimate the lateral tire force acting at each tire. A newly proposed SKFMEC (Scaled Kalman Filter with Model Emr Compensator) method is developed utilizing the conventional EKF (Extended Kalman Filter) method. Tire force estimation performance of the SKFMEC method is evaluated in the Matlab simulations where true tire force data is generated from a 14 DOF vehicle model with a combined-slip Magic Formula tire model.