본 연구는 보행로에서 주행하는 자율주행로봇의 경로 최적화를 위한 D*알고리즘 수정에 중점을 두고 있다. 기존의 D*알고리즘은 자율주행 로봇이 장애물을 인식하고 회피하는 방식으로 설계되었지만, 실제 보행환경에서는 보행로를 통행하는 사람들이 로봇을 인지 하고 스스로 회피하는 경향이 관찰되었다. 라이다 센서를 통해 수집된 사람들의 궤적 데이터를 분석하여, 사람들이 자율주행 로봇을 회피하기 시작하는 평균 거리와 회피 각도를 파악하였다. 이를 바탕으로, 사람들이 로봇을 회피할 의사가 있을 때 로봇이 기존 최적경 로를 유지하도록 하고, 그렇지 않은 경우에만 회피 경로를 채택하는 수정된 D*알고리즘을 제안하였다. 실험 결과, 수정된 D*알고리즘 을 적용한 자율주행 로봇은 운행 효율과 주행 시간 측면에서 기존 방식 대비 우수한 성능을 보였다. 이러한 연구는 제한된 배터리 용 량 하에서도 효율적인 주행이 가능하도록 하여 자율주행 로봇의 보행로 사용을 최적화하는 데 기여할 것으로 기대된다.

PURPOSES :In this study, we analyzed the road crossing behavior of older pedestrians on a mid-block signalized crosswalk, and compared it to that of younger pedestrians. In addition, we analyzed the correlation between accidents involving older pedestrians while crossing roads and their behavioral characteristics. Finally, we confirmed the reasons for an increase in accidents involving older pedestrians.METHODS :First, 30 areas with the highest incidence of accidents involving older pedestrians while crossing roads were selected as target areas for analysis. Next, we measured the start-up delay (the time elapsed from the moment the signal turns green to the moment the pedestrian starts walking) and head movement (the number of head turns during crossing a road) of 900 (450 older and 450 younger) pedestrians. The next step was to conduct a survey and confirm the differences in judgment between older and younger pedestrians about approaching vehicles. Finally, we analyzed the correlation between the survey results and traffic accidents.RESULTS :The average start-up delay and head movement of the older pedestrians was 1.58 seconds and 3.15 times, respectively. A definite correlation was obtained between head movement and the frequency of pedestrian traffic accidents. The results of our survey indicate that 17.3% of the older pedestrians and 7.8% of the younger pedestrians have a high crash risk.CONCLUSIONS :Behavioral characteristics of older pedestrians were closely correlated with accidents involving older pedestrians while crossing roads in mid-block signalized crosswalks. Our study indicates that in order to reduce the number of accidents involving older pedestrians, it is necessary to develop an improvement plan including measures such as installation of safety facilities taking the behavioral characteristics of older pedestrians into consideration and their safety education.

본 연구는 2016년 5월부터 2016년 9월에 경북 김천시 봉산면에서 장기간 도로로 단절된 경부고속도로(46년 전 완공) 및 경부선 철도(111년 전 완공)지역에서 종 구성의 변화와 다양성에 대해 알아보기 위해 보행성 딱정벌레르 대상으로 실시하였다. 조사 결과 딱정벌레과 11속 17종 287개체를 확인하였다. 우점종은 Synuchus nitidus 105개체 아우점종은 Coptolabrus jankowskii로 68개체가 확인되었다. 고립 지점과 비고립 지점에서 모두 확인된 종은 우점종과 아우점 종이며 Synuchus cycloderus, Nebria chinensis는 고립된 1개 지점을 제외한 서식지를 확인하였다. 고립과 지점에서 일부 종의 유전자 다양성에 대한 정보를 확보하기 위한 유전자 분석이 필요할 것으로 예상된다.

The purpose of this study was to compare spatio-temporal parameters during walking between patients with idiopathic Parkinson's disease and a control group matched for age, height, and weight. Thirty-three subjects were included in this study. Fifteen normal subjects (age, 63.3±5.8 yrs; height, 164.1±8.7 cm; weight, 60.7±17.5 kg) and eighteen patients (age, 64.0±7.7 yrs; height, 164.7±7.3 cm; weight, 63.6±7.7 kg) participated in the study. The Vicon 512 Motion analysis system was used for gait analysis in each group during walking, with and without an obstacle. The measured spatio-temporal parameters were cadence, walking speed, stride time, step time, single limb support time, double limb support time, stride length, and step length. Results in stride length and step length, when walking without an obstacle, showed a significantly greater decrease in the patient group compared to the control group. During walking with an obstacle, the patient group showed a significantly greater decrease in the step length as compared to the control group. For the control group, there were significant decreases in parameters of cadence and walking speed and increases in parameters of stride time, step time, and single limb support time when walking with an obstacle. The patient group had lower cadence and walking speed and higher stride time, step time, and single limb support time during walking with an obstacle than in walking without an obstacle. These results suggest that patients with Parkinson's disease who walk over an obstacle can decrease cadence, stride length, and step length. Further study is needed, performed with more obstacles and combined with other external cues, such as visual or acoustic guides.

This study investigated gait characteristics, kinematics, and kinetics in the lower extremities between two different shoe conditions (high heeled shoes (7 cm), and high heeled shoes with a total contact insert (TCI)) after lower extremity muscle fatigue. Although TCI shave been applied in high heeled shoes to increase comfort and to decrease foot pressure, no study has attempted to identify the effects of TCI in fatigue conditions. The purpose of this study was to determine the effects of walking in high heeled shoes with TCI after lower extremity muscle fatigue was induced. This study was carried out in a motion analysis laboratory at Hanseo University. A volunteer sample of 14 healthy female subjects participated. All in fatigue conditions, the subjects were divided into two groups. The muscle fatigue was induced by 40 voluntary dorsi- and plantar-flexion exercises and 40 heel-rise exercises of the dominant foot. Surface electromyography was used to confirm the localized muscle fatigue using power spectral analysis of three muscles (tibialis anterior, gastrocnemius medialis and lateralis). The results were as follows: (1) In muscle fatigue conditions, the use of TCI decreased the peak flexion angle of the hip joint significantly in the early stance phase (p<.05) and increased the peak hip flexion moment in the terminal stance phase (p<.05). (2) In muscle fatigue conditions, the application of TCI also increased peak hip power generation in the early stance phase and peak hip power absorption in the terminal stance phase (p<.05). (3) In muscle fatigue conditions, the use of TCI reduced the impact force significantly and increased the secondary peak vertical GRF. These findings suggest that the TCI may provide beneficial effects when muscle fatigue occurs for a high heeled shoe gait. Future research employing the patient population and various types of TCI materials are required to clarify the effects of TCI.

The purpose of this study was to investigate the effects of clinical characteristics of chronic stroke patients on physiological cost index (PCI) during walking. Fourteen stroke patients participated in this study. To investigate the clinical characteristics, Fugl-Meyer score (FMS), gait velocity (GV), muscle strength of the knee extensor, modified Ashworth scale (MAS) of ankle plantar flexor, devices, and gait patterns during walking were measured and analyzed. The results were as follows: Firstly, use of devices and high MAS of the ankle plantar flexor significantly increased PCI. Secondly, PCI was significantly correlated with the FMS and MAS of the ankle plantar flexor. In conclusion, inhibition of spasticity of the ankle plantar flexor is considered to reduce PCI during walking for chronic stroke patients.

An investigation was conducted to evaluate both the time required and the time allowed for persons to cross streets. Currently, the local municipality uses a standardized formula to determine the time allotted for 'WALK' signals to function allowing pedestrian traffic to cross thoroughfares. The formula to determine the 'Theoretical Time(in seconds)' is the width of the street(in meter) divided by 1.2m/s. The basis of the denominator is 'normal' walking speed. Initially, 3 locations were chosen to evaluate the time between the appearance of the 'WALK' signal and the appearance of the 'DON'T WALK'. The interval between the two signals was assumed to allow a person to begin crossing the street at the appearance of the 'WALK' signal and terminate their crossing at the appearance of the 'DON'T WALK' signal. Of the 3 locations, 2 locations(elementary?middle schools and general hospital areas), the duration of the 'WALK' signal were not properly set and therefore need more time for those who use these cross walks. Specific details regarding the crossing locations and validity of the standardized formula were also presented and discussed.

The purpose of this study was to determine the effect of lift to the shoe of the affected limb on gait patterns in subjects with hemiplegia. The subjects of this study were 18 post-stroke hemiplegics. For the study, insole of the paretic side was lifted 10mm higher, and duration of static weight bearing, dynamic weight bearing and stance phase were measured from one cycle of the gait, before and after the lift application. For the measurement of carry-over effect of lift, we got data of those three items prior to and 3 weeks after lift application and 3 days after removal of the lift. Static weight bearing was significantly increased both just after and continuous application of lift for 3 weeks than before. Dynamic weight bearing was significantly decreased in heel contact and footflat phases only when just after application of the lift, without any change after 3 weeks application. In heel-off phase, dynamic weight bearing did not show any significant difference between before and just after application of lift whereas significantly decreased after 3 weeks application. Duration of stance phase was not changed among anytime of application. According to this study, lift applied to the shoe of the peretic limb was effective in inducing static weight bearing in the paretic limb, but did not significantly effect dynamic weight bearing on gait patterns. This study suggests that symmetry, induced by shoe lift applied to the paretic limb, could help correct abnormal posture that would be caused in standing and prevent development of abnormal muscle tone in subjects with hemiplegia caused by unilateral stroke.

The purpose of this study was to compare the effects of anterior walker and posterior walker on gait parameters and body alignment of children with cerebral palsy. The intraclass correlation coefficient was .99 for intertester reliability. Intratester reliability was between .96 and .99. The use of posterior walker increased gait velocity and facilitated more upright posture. The measurement of joint angle program was found to be reliable to measure range of motion. This study has a limitation of generalizing the results to all children with cerebral palsy. Research is required to investigate the effect of posterior walker on energy efficiency.

The objective of this study was to identify the effects of pelvic tilting exercise on gait patterns of hemiplegic patients. The subjects of this study were 31 hemiplegic in- and out-patients of the Rehabilitation Hospital, Yonsei University Medical Center, from September 24, 1997 through November 5, 1997. Pre- and post-treatment change in gait patterns were measured using a ink foot-print. The data were analyzed by the paired t-test, one-way ANOVA, and independent t-test. The findings were as follows: The difference in gait patterns between pre- and post-treatment was statistically significant, with an increase in gait velocity to 7.98 cm/sec post-treatment; an increase in cadence to 7.29 steps/min; a narrowing of the base of support to 1.33 cm; an increase in step length of 3.92 cm on the less affected side and 3.73 cm on the more affected side; an increase in stride length of 5.82 cm on the less affected side and 5.92 cm on the more affected side(statistically not significant in foot angle). In relation to sex, age, cause of stroke, and laterality of paralysis, the difference in gait patterns between pre- and post-treatment was not statistically significant. Where there was no significant difference of the effects of pelvic exercise regarding the degree of spasticity, the presence of a decrease in proprioception, and the duration of treatment. In conclusion, hemiplegic pelvic tilting exercise was found to have transmitting positive effect in improving gait patterns.

The objective of this study was to identify the immediate effects of the short leg brace on the weight bearing distribution and gait patterns of hemiplegic patients. The subjects of this study were 18 hemiplegic patients who had been hospitalized or visited out-patient department of Rehabilitation Hospital, Yonsei University College of Medicine, from January 5, 1996 through March 23, 1996. PLS(Posterior Leaf Spring) on and off changes in gait patterns were measured using ink foot print as well as by recording weight bearing distribution using a limb load monitor. The data were analyzed by the correlation and paired t-test. The findings were as follows: 1. Eighteen subjects were more weighted on the affected leg when PLS was put off(42.74%) than on(40.08%). 2. The defference in gait patterns between PLS on and off was statistically significant, with an increase in step length by 1.7cm on the involved side; a decrease in foot angle by 4.41 degree on the involved side; and a narrowing of base of support by 1.46cm when PLS were off. In conclusion, this study showed that PLS did not affect the weight bearing distribution and gait patterns of hemiplegic patients. Since, the evaluation method used in this study has limitations in regard to temporal distance gait values. Further studies are required to numerous experiments for subject and extensive study.

The purpose of this study was to analyse the subtalar joint movement characteristics in human stance phase. The data of subtalar joint movement patterns are collected by CTA(calcaneus to tibia angle) measurements. CTA is defined as a angle formed between the bisect of the posterior shank and bisect of the posterior heel, as determined by placement of the retroreflective markers. The angle measured in degrees. The participants are 74 healthy individuals (37 men and 37 women) who have no orthopedic and neurological impairment, aged from 19 to 29 years(mean 22.95). Prior to participation, each subjecct informed the procedures of experiment from researcher and assistant researcher. The equipments of this study are walking grid, marking tapes, goniometer, video camera, monitor and ink for foot print are used in the study. In order to determine the statistical significance of result, the paired t-test and Pearson correlation were applied at the 0.05 level of significance. The results were as follows : 1. The reliability of measured CTA value are showed a high correlation, ranged from .86 - .94. 2. The mean value of step width are 7.67cm in men and 6cm in women. So, significant difference between men and women in 0.05 level of significance. 3. There was significant difference between man and women's TOA(toe out angle)(p<0.05). 4. The CTA of female's is more higher than male's one, however not statistical difference between man and women(p>0.05). 5. The CTA is reduced according to increasing TOA(p<0.05).

The objective of this study was to identify the effects of weight-transfer training on the weight bearing distribution and gait patterns of hemiplegic patients through visual and auditory feedback using a limb load monitor. The subjects of this study were 18 hemiplegic patients who had been hospitalized or were visited out-patient department of the Rehabilitation Hospital, College of Medicine, Yonsei University, from January 5, 1995 through March 15, 1995. Pre-and post-training changes in gait patterns were measured using ink foot prints as well as by recording weight bearing distribution using a limb load monitor. The data were analyzed by the repeated measure one-way ANOVA and paired t-test. The finding were as follows: 1. Prior to the training, 18 subjects bore more weight on the sound leg(61.6 %) than on the affected leg(38.4 %). 2. Posterior to the training, the average percentage of weight bearing on the affected leg increased significantly from 38.4 % prior to training; to 46.0 % immediately after training; 45.7 % after a 30 second delay; and 45.3 % after a 60 second 3. The difference in gait patterns between pre- and post- training was statistically significant, with an increase in gait velocity to 3.65 cm/sec post-training; an increase in stride length to 5.37 cm on the affected side; 4.77 cm on the sound side; and a narrowing of the base of support to 1.19 cm. In conclusion, hemiplegic weight-transfer training using visual and auditory feedback with a limb load monitor was found to be enhancing symmetrical standing posture, and simultaneously improve gait patterns.