• Korean Journal of Computational Design and Engineering
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• v.16 no.6
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• pp.424-436
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• 2011

In this paper, we propose a methodology of generating a parametric segment model for human body using the Korean anthropometric data. The model is defined as an articulated body model consisted with 19 ellipsoid primitives. The primitives are joined at locations representing the physical joints of human body. A lot of previous researches have suggested methodologies of generating body models using the European or American anthropometric data, so that these models were inappropriate for engineering analyses and simulations in case of the Koreans. We defined a set of 35 body dimensions representing our segment model based on the anthropometric data of Koreans. Also we defined four key parameters of age, height, weight and waist circumference, and then we applied regression equations to associate the parameters to the aforementioned dimensions. As the results, we obtained the parametric human body segment models according to the various body types and the subject-specific models for a specific individual. The models in the various industries can be used as the base models for static and dynamic analysis considering the Koreans.

• Nuclear Engineering and Technology
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• v.52 no.9
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• pp.1983-1989
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• 2020

The human reliability analysis is a method by which, in general terms, the human impact to the safety and risk of a nuclear power plant operation can be modelled, quantified and analysed. It is an indispensable element of the PSA process within the nuclear industry nowadays. The paper herein presents a sensitivity study of the human reliability analysis performed on a real nuclear power plant-specific probabilistic safety assessment model. The analysis is performed on a pre-selected set of post-initiator operator actions. The purpose of the study is to investigate the impact of these operator actions on the plant risk by altering their corresponding human error probabilities in a wide spectrum. The results direct the fact that the future effort should be focused on maintaining the current human reliability level, i.e. not letting it worsen, rather than improving it.

• Proceedings of the ESK Conference
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• 1993.04a
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• pp.1-9
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• 1993

A human gait study is required for the biomechanical design of running shoes. A tow-dimensional dynamic model was developed in order to analyze lower extremity kinematics and loadings at the right ankle, knee, and hip joints. The dynamic model consists of three segments, the upper leg, the lower leg, and the foot. Each segment was assumed to be a rigid body with one or two frictionless hinge joints. The lower extremity motion was assumed to be planar in the sagittal plane. A young male subject was involved in the gait test and his anthropometric data were measured for the calculation of segement mass and moment of inertia. The experimental data were obtained from three trials of walking at 1.2m/s. The foot-floor reaction data were measured from a Kistler force plate. The kinematic data were acquired using a three-dimensional motion measurement system (Expert Vision) with six markers, five of which were placed on the right lower extremity segments and the rest one was attached to the force plate. Based on the model and experimental data for the stance phase of the right foot, the calculated vertical forces reached up to 492, 540, and 561 N at the hip, knee, ankle joints, respectively. The flexion-extension moments reached up to 155, 119, and 33 Nm in magnitude at the corresponding joints.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1998.05a
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• pp.257-262
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• 1998

In order to understand the characteristics of electrostatic discharge (ESD) by a charged human body, a dynamic analysis method based on RCL circuit and a quasi-static analysis method based on two-body model are introduced. In this paper, these methods calculate waveforms, discharge energy and potential difference to analyze the ESD phenomena from given initial conditions and geometry. Results are compared and discussed.

• Journal of the Ergonomics Society of Korea
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• v.21 no.2
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• pp.13-23
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• 2002

Human dummies are essential tools in the development of such products as vehicle have been actively used not only in reach and view field tests. but also in impact perception evaluations. This study attempted to obtain geometric and dynamic model body segments from Korean anthropometric data. The investigation focused on the de both human and dummy for the geometric and inertial properties. The dynamic modeli being suggested is based on rigid body dynamics using fifteen individual body segments by joins. The segments are connected at the locations representing the physical joint body so that each segment has its mass and moment of inertia. For visual three-dimensional graphic was used for easier implementation of the dumn applications. For applications, proposed Korean dummies Were used in dynamic crash and driver's view and reach test modules were developed in virtual environment.

• Investigative Magnetic Resonance Imaging
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• v.23 no.1
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• pp.38-45
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• 2019

Purpose: To demonstrate the high-resolution numerical simulation of the respiration-induced dynamic $B_0$ shift in the head using generalized susceptibility voxel convolution (gSVC). Materials and Methods: Previous dynamic $B_0$ simulation research has been limited to low-resolution numerical models due to the large computational demands of conventional Fourier-based $B_0$ calculation methods. Here, we show that a recently-proposed gSVC method can simulate dynamic $B_0$ maps from a realistic breathing human body model with high spatiotemporal resolution in a time-efficient manner. For a human body model, we used the Extended Cardiac And Torso (XCAT) phantom originally developed for computed tomography. The spatial resolution (voxel size) was kept isotropic and varied from 1 to 10 mm. We calculated $B_0$ maps in the brain of the model at 10 equally spaced points in a respiration cycle and analyzed the spatial gradients of each of them. The results were compared with experimental measurements in the literature. Results: The simulation predicted a maximum temporal variation of the $B_0$ shift in the brain of about 7 Hz at 7T. The magnitudes of the respiration-induced $B_0$ gradient in the x (right/left), y (anterior/posterior), and z (head/feet) directions determined by volumetric linear fitting, were < 0.01 Hz/cm, 0.18 Hz/cm, and 0.26 Hz/cm, respectively. These compared favorably with previous reports. We found that simulation voxel sizes greater than 5 mm can produce unreliable results. Conclusion: We have presented an efficient simulation framework for respiration-induced $B_0$ variation in the head. The method can be used to predict $B_0$ shifts with high spatiotemporal resolution under different breathing conditions and aid in the design of dynamic $B_0$ compensation strategies.

• The Journal of Korea Robotics Society
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• v.8 no.1
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• pp.20-28
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• 2013

Large workspace and strong grasping force are required when a robot manipulates big and/or heavy objects. In that situation, bimanual manipulation is more useful than unimanual manipulation. However, the control of both hands to manipulate an object requires a more complex model compared to unimanual manipulation. Learning by human demonstration is a useful technique for a robot to learn a model. In this paper, we propose an imitation learning method of bimanual object manipulation by human demonstrations. For robust imitation of bimanual object manipulation, movement trajectories of two hands are encoded as a movement trajectory of the object and a force trajectory to grasp the object. The movement trajectory of the object is modeled by using the framework of dynamic movement primitives, which represent demonstrated movements with a set of goal-directed dynamic equations. The force trajectory to grasp an object is also modeled as a dynamic equation with an adjustable force term. These equations have an adjustable force term, where locally weighted regression and multiple linear regression methods are employed, to imitate complex non-linear movements of human demonstrations. In order to show the effectiveness our proposed method, a movement skill of pick-and-place in simulation environment is shown.

• Journal of Biomedical Engineering Research
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• v.16 no.4
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• pp.491-498
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• 1995

A numerical human head/neck model was constructed for analyzing the implication in decleration injuries. This model consists of nine rigid bodies representing the head, cervical vertebrae C1-C7, and T1. These rigid bodies were connected by intervertebral disks described by massless beam elements. Muscles and ligaments were also incoperated in the model represented by nonlinear spring and viscoblastic element respectively Agreement of the analytical kinematic response with the results of experimental data from a volunteer run was satisfactory. Moreover, possible injury estimation from the calculated moment, force variations in the disc, and force variation in ligaments matched well with clinical observations.

• IE interfaces
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• v.17 no.1
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• pp.22-32
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• 2004

The most complicated and difficult area in the simulation of evacuation process is the area of human behavior. However, it is generally very difficult to understand and quantify human behaviors since the factors involved vary significantly according to the types of accidents and the environment. The walking speed of passenger is especially affected by dynamic effect and list due to damage and ship motion in wave. There are various methods to get the useful data for evacuation simulation. The onboard experimental approach is one of the strongest method. This paper discusses the onboard experimental results of human mobility of passengers in evacuation from ship. To realize ship trim and heel due to maritime casuality, the passage model for experiment is made. The experiment was carried out at dynamic and static condition respectively using the ship with passage model. The result was evaluated and it will be reflected in evacuation simulation tool.

• Journal of the Society of Naval Architects of Korea
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• v.41 no.3
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• pp.41-48
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• 2004

Ship is being operated under a highly dynamic environments and many factors are related with ship's collision and those factors are interacting. So, the analysis on ship's collision causes are very important to prepare countermeasures which will ensure the safe navigation. This study analysed the ship's collision data over the past 10 years(1991-2000), which is compiled by Korea Marine Accidents Inquiry Agency. The analysis confirmed that ‘ship's collision' is occurred most frequently and the cause is closely related with human factor. The main purpose of this study is to propose risk control measures of ship's collision. For this, the structure of human factor is analysed by the questionnaire methodology. Marine experts were surveyed based on major elements that were extracted from the human factor affecting to ship's collision. FSM has been widely adopted in modeling a dynamic system which is composed of human factors. Then, the structure analysis on the causes of ship's collision are performed using FSM. This structure model could be used in understanding and verifying the procedure of real ship's collision. Furthermore it could be used as the model to prevent ship's collision and reduce marine accidents.