• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.7 no.1
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• pp.87-98
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• 1997

In this study, subway train vibration has been measured to characterize the whole body vibration of Seoul subway lines for various human postures. Results show that the floor vibration level of the subway trains in the vertical direction is higher than that in other directions. At the standing human posture, vibration level of the head in the right-left direction are increased while that in the vertical direction is decreased. It is assumed that the different flexibility of the human body and the rolling motion of the subway trains are the main cause. At the sitting posture with back seat on, vibration level in the right and left direction at the human ischial tuberosities is lower than that in other directions. Results also show that there were little difference between back-seat on model and back-seat off model. Transmissibility analysis shows how the subway vibration affects the response of a human body.

• Parasites, Hosts and Diseases
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• v.58 no.3
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• pp.279-285
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• 2020

We intended to describe 2 digenean trematodes found from a Chinese sea snake, Laticauda semifasciata, as the new fauna in the Republic of Korea. The snake was caught offshore of Aewol-eup, Jeju-do, in August 2017. Two species of fluke were found in the lung and intestinal tract of the snake in the process of necropsy. They were identified as Pulmovermis cyanovitellosus Coil and Kuntz, 1960 and Harmotrema laticaudae Yamaguti, 1933, respectively based on the morphological characters. Pulmovermis cyanovitellosus showed elongated body with well-developed and elongated male genital system and compact vitelline. And H. laticaudae was characterized by linguiform body with heavily armed cirrus with excretory system. This is the first time both species have been reported and described off the Korean coast. We provide morphological descriptions with some comments on their biology and geographical distribution. In addition, the taxonomic validity of the genus Hydrophitrema Sandars, 1960 was discussed, in terms of morphological descriptions and host ranges. This study provides novel insight into digenean fluke species existing off the coast of Korea.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.5 no.1
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• pp.35-40
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• 2011

In this paper, we analyze that co-channel interference mitigation algorithms MMSE (Minimum Mean Square Error), OC (Optimal Combining), ML (Maximum Likelihood) using 2.4Ghz in WBAN (Wireless Body Area Network) system. Also analyze that scenario and channel model by IEEE 802.15.6. ML gives the best performance for all simulation. ML and OC have high complexity than MMSE complexity, because these algorithms should be known channel information of interference users. So these algorithms are difficult to apply to WBAN. Therefore we will study the interference mitigation algorithm that should be accomplished trade-off of between efficiency and complexity.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2138-2142
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• 2005

A wearable sensor system is proposed as a man-machine interface to control a device for walking assistance. The sensor system is composed of small sensors to detect the information about the user's body motion such as the activity level of skeletal muscles and the acceleration of each body parts. Each sensor includes a microcomputer and all the sensors are connected into a network by using the serial communication function of the microcomputer. The whole network is integrated into a belt made of soft fabric, thus, users can put on/off very easily. The sensor system is very reliable because of its decentralized network configuration. The body information obtained from the sensor system is used for controlling the assisting device to achieve a comfortable and an effective walking training.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.10
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• pp.194-199
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• 2001

In this paper, we propose a new locomotive mechanism using impulsive force for microcapsule-type endoscope. It has the compact size for movement in the colon and actuating mechanisms for hi-directional movement. The actuating mechanism resembles a pneumatic cylinder and consists of body, inertia mass(piston). spring. pneumatic source and calve. When valve is ON, the pneumatic impulsive force between piston and body drives them in two opposite direction. As the air in the body is passed away, the contrary movements are occurred by spring reaction. Therefore, the direction of body's motion is determined by the relative magnitude of two opposite impulsive forces, i.e., pneumatic and spring force. The effect of two impulsive forces can simply be controlled by On-Off time of solenoid valve.

• Journal of applied mathematics & informatics
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• v.15 no.1_2
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• pp.127-146
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• 2004

In this paper we consider a heat flow in an inhomogeneous. body without internal source. There exists special initial and boundary conditions in this system and we intend to find a convenient coefficient of heat conduction for this body so that body cool off as much as possible after definite time. We consider this problem in a general form as an optimal control problem which coefficient of heat conduction is optimal function. Then we replace this problem by another in which we seek to minimize a linear form over a subset of the product of two measures space defined by linear equalities. Then we construct an approximately optimal control.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.4
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• pp.482-487
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• 2008

In case of flooding, the underwater flight vehicle (UFV) executes the blowing by blowing ballast tanks off using high pressure air (HPA), while it also uses control planes and a propulsion unit to reduce the overshoot depth caused by a flooding and blowing sequence. However, the conventional whole HPA blow-off method lets the body on the surface after blowing despite slight flooding. This results in the unnecessary mission failure or body exposure. Therefore, it is necessary to keep the body at the near surface by the blowing control while reducing the overshoot depth. To solve this problem, an adaptive blowing control algorithm, which is based on the decomposition method expanding the expert knowledge in depth control and the adaptive method using fuzzy basis function expansion (FBFE), is proposed. To verify the performance of the proposed algorithm, the blowing control of UFV is performed. Simulation results show that the proposed algorithm effectively solves the problems in the UFV blowing control system online.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.52 no.8
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• pp.500-505
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• 2003

In this paper, the method to register multiple sets of skull CT images to absolute coordinate system is proposed. Contrary to correspondence paired mapping of previous techniques, four anatomical landmark points, three coplanar points and one non-coplanar point, compose three principal axes simple and unique for efficient registration by means of rigid body transformation. Throughout the numerical simulation with added random noises, the error performances in terms of different rotation and rounding-off of landmark points, and incorrect localization of anatomical landmark and target points are quantitatively analyzed to generalize the proposed technique. Experiments using real skull CT images demonstrate the feasibility for an efficient use in clinical practice.

• The Transactions of the Korean Institute of Power Electronics
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• v.7 no.6
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• pp.524-530
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• 2002

A control of the body posture and movement is maintained by the vestibular system, vision, and proprioceptors. Afferent signals from those receptors are transmitted to the vestibular nuclear complex, and the efferent signals from the vestibular nuclear complex control the eye movement and skeletal muscle contract. The postural disturbance caused by loss of the vestibular function results in nausea, vomiting, vertigo and loss of craving for life. The purpose of this study is to develop a off-vertical rotatory system for evaluating the function of semicircular canals and otolith organs, selectively, and visual stimulation system for- stimulation with horizontal, vortical and 3D patterns. The Off-vortical axis rotator is composed of a comportable chair, a DC servo-motor with reducer and a tilting table controlled by PMSM. And a double feedback loop system containing a velocity feedback loop and a position feedback loop is applied to the servo controlled rotatory chair system. Horizontal, vertical, and 3D patterns of the visual stimulation for applying head mounted display are developed. And wireless portable systems for optokinetic stimulation and recording system of the eye movement is also constructed. The gain, phase, and symmetry is obtained from analysis of the eye movement induced by vestibular and visual stimulation. Detailed data were described.

• Journal of the Korean Society of Costume
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• v.58 no.9
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• pp.166-175
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• 2008

For the structural firefighting protective clothing, it can show a synergy effect when it satisfies smart fabric to block off a harmful environmental element and ergonomics design that apply range of motion of human body and appropriate size system. There are various standards about the structural firefighting protective clothing, but it's difficult to find a rule about movement suitability because the performance of the material holds a lot of the rules. Therefore, the purpose of this study is to propose a scheme to evaluate the current structural firefighting protective clothing and to improve movement suitability by research on the actual condition. For this, the survey about wearer acceptability scale on design and size and about improvement requirements was executed gathering firefighters' opinion. Questionnaire was composed with 23 items about satisfaction on current structural firefighting protective clothing, body suitability, movement suitability, improvement requirement and subjective information. As a results, Korean firefighters demand ergonomics design of structural firefighting protective clothing which to minimize restriction of body movement and to maximize body suitability.