• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.10
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• pp.1751-1768
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• 2011

Falls are one of the most concerned accidents for elderly people and often result in serious physical and psychological consequences. Many researchers have studied fall detection techniques in various domain, however none released to a commercial product satisfying user requirements. We present a systematic modeling and evaluating procedure for best classification performance and then do experiments for comparing the performance of six procedures to get a statistical classifier based wrist-type fall detector to prevent dangerous consequences from falls. Even though the wrist may be the most difficult measurement location on the body to discern a fall event, the proposed feature deduction process and fall classification procedures shows positive results by using data sets of fall and general activity as two classes.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.4
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• pp.395-399
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• 2006

A method to recognize unpaved road region using a 3D depth measurement system is proposed for mobile robots. For autonomous maneuvering of mobile robots, recognition of obstacles or recognition of road region is the essential task. In this paper, the 3D depth measurement system which is composed of a rotating mirror, a line laser and mono-camera is employed to detect depth, where the laser light is reflected by the mirror and projected to the scene objects whose locations are to be determined. The obtained depth information is converted into an image. Such depth images of the road region represent even and plane while that of off-road region is irregular or textured. Therefore, the problem falls into a texture identification problem. Road region is detected employing a simple spatial differentiation technique to detect the plain textured area. Identification results of the diverse situation of unpaved trail are included in this paper.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.517-518
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• 2007

A method to recognize unpaved road region using a 3D depth measurement system is proposed for mobile robots. For autonomous maneuvering of mobile robots, recognition of obstacles or recognition of road region is the essential task. In this paper, the 3D depth measurement system which is composed of a rotating mirror, a line laser and mono-camera is employed to detect depth, where the laser light is reflected by the mirror and projected to the scene objects whose locations are to be determined. The obtained depth information is converted into an image. Such depth images of the road region represent even and plane while that of off-road region is irregular or textured. Therefore, the problem falls into a texture identification problem. Road region is detected employing a simple spatial differentiation technique to detect the plain textured area. Identification results of the diverse situation of Nonlinear trail are included in this paper.

• Journal of Biomedical Engineering Research
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• v.23 no.5
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• pp.397-403
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• 2002

Urine glucose monitoring system is a self-monitoring system that display the glucose level by non-invasive measurement method. In this paper, We developed a noninvasive urine glucose monitoring system that improved defects of urine glucose measurement with a colorimeter method and invasive blood glucose measurement method. This system consist of bio-chemical sensor for urine glucose measurements, signal detecting part, digital and signal analysis part, display part and power supplying part. The developed bio-chemical sensor for the measurement of urine glucose has good reproducibility, convenience of handing and can be mass-produced with cheap price. To evaluate the performance of the developed system, We performed the evaluation of confidence about the detection of glucose level by a comparison between a standard instrument in measuring glucose level and the developed system using standard glucose solutions mixed with urine. Standard error was 2.85282 from the evaluation of confidence based on regression analysis. Also, In analysis of S.D(standard deviation) and C.V(coefficient of validation) that are important parameters to evaluate system using bio-chemical sensor, S.D was 10% which falls under clinically valid value, 15%, and C.V was under 5%. Consequently from the above results, compared to blood glucose measurement, the system performance is satisfactory.

• Journal of Korean Society of Water and Wastewater
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• v.19 no.3
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• pp.348-356
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• 2005

Water quality sampling surveys and continuous measurement of flow were conducted to identify wastewater flow characteristics for representative catchment of O and M treatment basins in A city. For HS-1 station representing commercial area, wastewater flow rises in the beginning of office-working hours, moves up and down within narrow range, and lasts till office-leaving hour, and falls gradually reflecting worker's returning home. However, in HS-2 station representing residential area, wastewater flow has two peaks, which are before office-going hour and after office-leaving hour. In residential area, the flow rate of weekends is higher than that of weekdays because it reflects population, being not contributed to generate wastewater during the working hours of weekdays, stay home and produce wastewater for weekends period. To determine the priority for rehabilitation of sewer system, infiltration rate was computed by dividing infiltration flow by mean diameter and total length of sewer, and HS-1 station ranked the first.

• Journal of The Korean Society of Integrative Medicine
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• v.4 no.2
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• pp.1-11
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• 2016

Purpose : The purpose of this study was to identify whether virtual reality-based exercise could improve on balance, gait and fall efficacy in patients with Parkinson's disease. Methods : Ten patients with Parkinson's disease were randomly divided into either an experimental or control group. The experimental subjects performed vertual reality-based exercise, whereas the control subjects performed conventional physical therapy for 4 weeks. The balance, gait and fall efficacy of all subjects were assessed by using the Measurement Training and Documentation (MTD) balance system, force platform system, Korean version of Berg Balance scale (K-BBS), 6 Minute Walk Test (6MWT), and Korean version of Fall efficacy scale (K-FES) at pre training and post training. Wilcoxon signed rank test was used to analyze change before and after intervention in intra-group. Mann Whitney U test was used to analyze changes of all variables in inter-groups. Results : Subjects in the experimental group showed significant improvements in difference of weight distribution, K-BBS scores, antero-posterior and medio-lateral sway length, ground reaction force (GRF), 6MWT, and step length following training. The changes of difference of weight distribution, K-BBS scores, AP Sway Length, GRF, 6MWT, step length and K-FES scores in the experimental group were significantly more than them of the control group. Conclusion : The result of this study suggest that virtual reality-based exercise training is an intervention to improve on balance, gait, and falls efficacy in patients with Parkinson's disease.

• The Journal of Korea Robotics Society
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• v.15 no.3
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• pp.286-292
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• 2020

This paper is about a fall inducement system for guiding like a real fall. Reliable fall data can be used as an essential element in developing effective fall protection devices. We can get this data if the induced fall is very realistic. The proposed system analyzes gait characteristics and determines when to fall based on the pedestrian's biometric data. To estimate the fall inducement time, an active estimation algorithm was proposed using different biometric values for each pedestrian. The proposed algorithm is designed to response actively to the ratio of gait cycle and a stance period. To verify this system, an experimental environment was implemented using a multi-rail treadmill equipped with a ground reaction force measurement device. An experiment was conducted to induce falls to pedestrians using a fall inducement system. By comparing the experimental scene to the video of the actual fall, it has been confirmed that the proposed system can induce a reliable fall.

• Journal of the Korea Society of Computer and Information
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• v.17 no.4
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• pp.1-9
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• 2012

As we are turnning into the aged society, accidents by falling down are increasing in the aged people's group. In this paper, we design the system with the 3-Axis acceleration sensor which is composed by a single chip. The body activity signal is measured with the signal detector and RF communicator in this proposed system and the and falling by the entering signal pattern analysis with 3-Axis acceleration sensor. For the RF communication, we are using nRF24L01p and 8bits ATmega uC for the processor. The error of energy expenditure estimation between motor driven treadmill and proposed a body activity module was 7.8% respectively. Human activities and falling is monitored according to analyze and judge the critical value of the Signal Vector. as falled down if they don't turn off the alarm after specific period and the aged person's after falling down activities are their position and more.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.3
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• pp.521-526
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• 2023

Due to the recent pandemic, most educational systems are being conducted through online classes. Unlike face-to-face classes, it is even more difficult for learners to maintain concentration, and evaluating the learners' attitude toward the class is also challenging. In this paper, we proposed a real-time concentration-based review support system for learners in real-time video lectures that can be used in online classes. This system measured the learner's face, pupils, and user activity in real-time using the equipment used in the existing video system, and delivers real-time concentration measurement values to the instructor in various forms. At the same time, if the concentration measurement value falls below a certain level, the system alerted the learner and records the timestamp of the lecture. By using this system, instructors can evaluate the learners' participation in the class in real-time and help to improve their class abilities.

• The Research Journal of the Costume Culture
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• v.31 no.5
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• pp.627-639
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• 2023

This study seeks to increase the satisfaction of elderly men when purchasing and wearing ready-to-wear clothes by designing a slacks pattern suitable for their body type, which is determined by analyzing their lower bodies using virtual avatars and 3D virtual simulation system. The study found the following. First, based on virtual visualization of the comparison slacks pattern, the waistline position was consistently the lowest scored question among the evaluation survey items. Interpretation of this dissatisfaction suggests that, because the front waistline falls below the abdomen, the lower body, and especially the abdominal shape, is unpleasantly emphasized. Second, by using a virtual simulation system, the study developed a new slacks pattern that considered the concerns of elderly men. The primary measurement changes were as follows: front waist girth W/4+1.5cm+0.5cm, back waist girth W/4+1.5cm-0.5cm, front hip girth H/4+2.5cm-0.5cm, back hip girth H/4+2.5cm+0.5cm. Third, the new slacks pattern's appearance was evaluated more highly than the comparison pattern, confirming the new pattern's appropriateness for elderly men. This study demonstrates how slacks and other clothing patterns designed in a 3D virtual garment simulator can be used to design more appealing clothing for elderly men, increasing the satisfaction of wearing ready-made clothes at older ages.