• ETRI Journal
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• v.29 no.4
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• pp.507-515
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• 2007

Skeleton transform of which the medial axis transform is the most popular has been proposed as a useful shape abstraction tool for the representation and modeling of human posture. This paper explains this proposition with a description of the areas in which skeletons could serve to enable the representation of shapes. We present algorithms for two-dimensional posture modeling using the developed simplified shock graph (SSG). The efficacy of SSG extracted feature vectors as shape descriptors are also evaluated using three different classifiers, namely, decision tree, multilayer perceptron, and support vector machine. The paper concludes with a discussion of the issues involved in using shock graphs to model and classify human postures.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.3
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• pp.250-256
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• 2015

We present a novel method to model the body posture of a worm for vision-based automatic monitoring and analysis. The worm considered in this study is a Caenorhabditis elegans (C. elegans), which is popularly used for research in biological science and engineering. We model the posture by an open chain of a few curved or rigid line segments, in contrast to previously published approaches wherein a large number of small rigid elements are connected for the modeling. Each link segment is represented by only two parameters: an arc angle and an arc length for a curved segment, or an orientation angle and a link length for a straight line segment. Links in the proposed method can be readily related using the Denavit-Hartenberg convention due to similarities to the kinematics of an articulated manipulator. Our method was tested with real worm images, and accurate results were obtained.

• Journal of Korean Institute of Industrial Engineers
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• v.34 no.1
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• pp.57-65
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• 2008

In the vehicle design, the research on driving posture has stood out as one of the important issues. Recently, the research on 3D human modeling focused on more exact implementation of real driving posture. However, prediction of driving posture through the 3D human modeling fail to reflect on the model the phenomenon called sagging, which refers to the retraction or shrinking of the torso while driving. 30 male subjects participated in the experiment where total subjects were divided into four groups according to height percentile(under 50%ile, 51%ile to 75%ile, 76%ile to 95%ile, over 95%ile). The independent variables were seat back angle(4 levels) and seat pan angle(2 levels). The dependent variable was capacity or the degree of retraction of the torso. First this study measured the sagging capacity by using a paired T-test between erect and retracted posture. Secondly it was tried to find out significant anthropometric variables that were statistically correlated by the analysis of correlation. Finally, a prediction model was derived which explains the capacity of sagging.

• Journal of the Ergonomics Society of Korea
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• v.32 no.5
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• pp.475-480
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• 2013

Objective: In this study, virtual reality was adopted to consider ergonomic factors in yacht design. Virtual human which is the same actual human was created in virtual environment using Digital Human Modeling which has been used in the manufacturing communities to design better workplaces and maximize the safety of workers. Background: During the past 40 years yachting has expanded from being, generally speaking, a minority sport - too expensive for the large majority of people - into a major recreational activity practiced by millions all over the world. Many new yacht designs have appeared and number of professional, as well as amateur designers has increased steadily. But they had not considered ergonomic factors in yacht design. Method: Worker's posture, traffic line and workload had been analyzed in sailing yacht. After the caution level was evaluated, we pointed out clues which had high workload and interference. To reduce workload, we applied ergonomic principles for improving working conditions and environments in Digital Human Model. Results: We found the space problems and workload of postures. Conclusion: (1) Unnatural posture of crews was sustained. (2) Workload that occurs in the human body was overloaded. (3) Crew's work space was very narrow. Application: This study will be applied the new ergonomic design of yacht.

• Journal of Fashion Business
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• v.25 no.3
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• pp.71-89
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• 2021

The purpose of this study was to design posture braces for rounded shoulders by examining characteristics of incorrect postures of rounded shoulders. The review of information in literature on rounded shoulder postures, correction exercise methods, and posture correction devices, has prompted this study to determine the design and material of a proper posture brace for rounded shoulders. In order to develop the pattern of a posture brace for rounded shoulders for women, the study carried out a comfort evaluation of the braces based on the 2D patterns through drafting method by utilizing the body measurements and relational formulae associated with the major body measurement such as bust circumference and on the 3D patterns of the brace which were obtained from 3D human model of women in their early 20s in Korea. Differences in angles were noted when 2D and 3D patterns of shoulder posture braces were compared. The side neck point was relocated farther outside in the 3D pattern to allow additional flexibility in the back-neck area, and the shoulder band was lowered by 14.8°, increasing armhole area comfort. The upper hemline of the front panel was found to rotate upward at an angle of 22.0° as the underarm point of the 3D pattern moved upwards than the underarm point of the 2D pattern, which enhanced comfort in the abdomen area. The 3D designs of shoulder posture brace was preferred in this study, as they significantly improved comfort while conducting fit evaluation compared to the 2D patterns of shoulder posture brace.

• Journal of Ocean Engineering and Technology
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• v.22 no.5
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• pp.119-125
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• 2008

Musculoskeletal disorders(MSDs) are one of the major issues in shipbuilding industry. Main risk factors of MSDs include manual handling of heavy weight, awkward posture, repetitive tasks, prolonged static muscle contraction, and so on. in this study, Using the three-dimensional digital human modeling and simulation method we made up a worker and work posture on a virtual environment. To verify this simulation we compared both traditional ergonomic analysis on a real worker and digital program analysis on a digital human. And this paper shows that it is possible to reduce the rate of MSDs in the shipbuilding industry because it means we can change poor posture mid surroundings into better ones.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.459-464
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• 2004

The rifle impact of human body affected by the posture of human for rifling. The interaction human-rifle system influence the firing accuracy. In this paper, impact analysis of human model for shooting posture is carried out. ADAMS code and LifeMOD is used in impact analysis of human model and modeling of the human body, respectively. On the shooting, human model is affected by rifle impact during the 0.001 second. Performed simulation time for shooting is 0.1 second. Applied constraint condition to human-rifle system is rotating and spherical condition. As the results, the displacement of rifle and transfer path analysis of impact of human model is presented.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.3
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• pp.183-190
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• 2016

In this study, we conduct linear and nonlinear modeling of the DC motor driving system of a wheeled mobile robot, which is a nonlinear system involving dead zone, friction, and saturation. The DC motor driving system consists of a DC motor, a wheel, and gears. A linear DC motor driving system is modeled using a steady-state response and parameter measurements. A nonlinear DC motor driving model is identified with the use of the Hammerstein-Wiener method. By using these models, PID controllers for the DC motor system are then established. Each PID controller is applied as a low-level controller in order to achieve posture stabilization control for the real mobile robot. We also compare the performance of the proposed PID controllers in posture stabilization experiments by using several different final robot postures.

• Proceedings of the KIEE Conference
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• 1999.11c
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• pp.655-657
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• 1999

In this paper we will introduce an posture error reduction algorithm for Mobile Robot. We classified odometry error into two categories. and focus on systematic odometry error correction only. Because it is the primary reason for mobile robot navigation. For this procedure we used some robot specifications and modeled robot behavior. Through some experiment, we could obtain new system specs. After modeling, Robot navigation precision was improved.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.105-108
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• 2004

This paper introduces a process of the development of a vibration test dummy for the posture of inclined seating. Experimental devices was invented to measure apparent mass curves on the contact point of the hip and the back of a seated human body. During the excitation of a rigid seat secured to a hydraulic exciter, force and acceleration signals were measured on the contact points to determine the apparent mass. In order to describe nonlinear characteristics of a human body, seven levels of Gaussian random signal were used for the base excitation. The modeling of the human body will be performed using measured apparent mass curves. The modeling will be done by June and the prototype of the test dummy will be invented in the following six months.