• International Journal of Automotive Technology
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• v.3 no.1
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• pp.27-32
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• 2002

Semi-active suspension systems are greatly expected to be in the mainstream of future controlled suspensions fur passenger cars. In this study, a continuous variable damper for a passenger car suspension is developed. It is controlled actively and exhibits high performance with light weight, low cost, and low energy consumption. To get fast response of the damper, reverse damping mechanism is adapted, and to get small pressure change rate after blow-off, a pilot controlled proportional valve is designed and analyzed. The reverse continuous variable damper is designed as a HS-SH damper which offers good body control with reduced transferred input force from tire, compared with any other type of suspension system. The damper structure is designed, so that rebound and compression damping force can be tuned independently, of which variable valve is placed externally. The rate of pressure change with respect to the flow rate after blow-offbecomes smooth when the fixed orifice size increases. Damping forces are measured with the change of the solenoid current at the different piston velocities to confirm the maximum hysteresis of 20N, linearity, and variance of damping farce. The damping farce variance is wide and continuous, and is controlled by the spoof opening, of which scheme is usually adapted in proportional valves. The reverse continuous variable damper developed in this study is expected to be utilized in the semi-active suspension systems in passenger cars after its performance and simplicity of the design is confirmed through real car test.

• Journal of Wetlands Research
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• v.12 no.3
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• pp.165-175
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• 2010

Recently, various development projects have occurred due to rapid industrialization and urbanization. Both industry and population grew rapidly which causes a corresponding rise in pollution. The accumulated pollutants are washed-off during rainy days, highly degrading the water quality of the receiving water body. This is because a lot of non point source (NPS) pollutants were accumulated on the surface during dry periods. This research focuses on the development of Eco-Bio Filter (EBF) system that treats NPS pollutants. It is constructed at Kongju National University campus. The EBF is a type of a structured infiltration system that falls under the category of Low Impact Development (LID) hydrologic design practices. The monitoring of rain events was performed. It includes the development of design, the lessons learned from the post-construction testing and the improvements in the renovation made. After a series of monitoring, the MOE will use the results to apply the design to other areas in the country.

• Food Science and Industry
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• v.49 no.4
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• pp.40-63
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• 2016

John Glenn, America's first man to eat anything in the near-weightless environment of Earth orbit, found the task of eating fairly easy. With improved packaging came improved food quality and menus. By the time of the Apollo Program, the quality and variety of food increased even further. Apollo astronauts were the first to have hot water, which made rehydrating foods easier and improved the food's taste. Thermostabilized pouches were also introduced on Apollo. The task of eating in space got a big boost in Skylab. It also had a food freezer and refrigerator a convenience offered by no other vehicle before or since. Two different food systems will be used for future long-duration missions to other planets, one for traveling to and from the distant body and one for use on the surface of the moon or Mars. The transit food system will be similar to the space station food system with the exception that products with three-to five-year shelf lives will be needed. Thus, this part of the trip will be similar to what occurs aboard space missions now. The surface food system, be it lunar or planetary, will be quite different. It will be similar to a vegetarian diet that someone could cook on Earth. Once crew members arrive on the surface and establish living quarters, they can start growing crops. Once the crops are processed into edible ingredients, cooking will be done in the spacecraft's galley to make the food items. Disposal of used food packaging will be an issue since there will be no Progress vehicles to send off and incinerate into the Earth's atmosphere. Packaging materials will be used that have less mass but sufficient barrier properties for oxygen and water to maintain shelf life as those now in use.

• Journal of the Korea Computer Graphics Society
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• v.24 no.3
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• pp.93-100
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• 2018

This paper proposes a small-scale rehabilitation system that allows stroke patients to perform daily rehabilitation training in a virtual home. Stroke patients have limited activities of daily living due to paralysis, and there are many rehabilitation exercises for them to reproduce activities that take place in the house, such as turning lights on and off, door opening and closing, gas valve locking. In this paper, we have implemented a virtual home with the above mentioned daily rehabilitation training elements, by using virtual reality technology. We use Leap Motion, a hand motion recognition device, for rehabilitation of hands and fingers. It is expected that stroke patients can rehabilitate small muscles without having to visit the clinic with uncomfortable body, and will be able to get interesting rehabilitation training by avoiding monotony of existing rehabilitation tools.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.5
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• pp.475-480
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• 2012

This study on the methode is easied to distinguish with emotional visual lighting on AtoN facility using 3colors LED, and which is controlled to on-off switching of approach light in shore or harbor. The identification have easied to provide a differentiation between the AtoN facility of red and white light and surrounding light in harbor both sides. And the integrated controller have designed to left-right and serial sequential lighting system for harbor guidance using the GPS synchronous or timer. There is expectation effect that is prevent a confusion about distinguish of facility by ship's operator and to beautify a night scene of harbor, which is expressed to emotional identification lighting and variable color lighting on AtoN body by vertical layer color lighting using LED. In addition, the performance of AtoN is implemented to display with guidance light the harbor safety message by morse code lighting. Effectiveness of system is enhanced that age and power consumption reduce by candle alternated high light LED.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.155.1-155.1
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• 2011

The Korea Astronomy and Space Science Institute (KASI) and the Department of Astronomy at the University of Texas at Austin (UT) are developing a near infrared wide-band high resolution spectrograph, IGRINS (Immersion Grating Infrared Spectrograph). The white-pupil design of the instrument optics uses 7 cryogenic mirrors including 3 aspherical off-axis collimators and 4 flat fold mirrors. Two of the 3 collimators are H- and K-band pupil transfer mirrors and they are designed as compensators for the system alignment in each channel. Therefore, their mount design will be one of the most sensitive parts in the IGRINS optomechanical system. The other flat fold mirrors are designed within the limited area. Each of those includes the features of 3 axial hard points and 2 radial hard points with one spring plunger in order for the proper deflection of the mirror. The design work will include the computer-aided 3D modeling and finite element analysis (FEA) to optimize the structural stability and the thermal behavior of the mount models. The mount body will also include a tip-tilt and translation adjustment mechanism to be used as the alignment compensators.

• Economic and Environmental Geology
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• v.44 no.4
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• pp.313-320
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• 2011

The Taebaegsan Mineralized District is the most prospective region for the useful mineral commodities such as a coal, non-metallic, metallic mineral in South Korea. From a general point of view, Cambro- Ordovician limestone formations, Myobong slate and Pungchon (Daegi) limestone, are the most fertilizable formations in the Taebaegsan Mineralized District. The geology around Weondong mine area consists mainly of Carboniferous-Triassic formations and Cambro-Ordovician formations intruded by rhyolite/quartz porphyry. The great overthrusted fault of N40~$50^{\circ}E$ direction, so called Weondong overthrust fault, is observed in the central part of the mine area and the NS fault system cuts the overthrusted fault. By postulating from the favorable geological and structural condition around Weondong area, the possibility of deep seated hidden ore bodies is expected. In 2010, on the basis of the results of LOTEM and CSAMT survey, the cross-hole survey was performed for the investigation of the hidden polymetallic ore body in the deep parts of the Weondong mine area and the grade of the newly-discovered orebody is as follows; (1) The cut-off grade for lead-zinc 3%; an weighted average grade 5.50% (2.7 m), (2) The cutoff grade for copper 0.1%; an weighted average grade 0.91% (14.65 m), (3) The cut-off grade for iron 30%; an weighted average grade 38.18% (3.3 m), (4) $WO_3$ for each cut-off grade(0.01%, 0.05%, 0.1%); an weighted average grade 0.29 wt. % (8.8 m), 1.15 wt. % (2.1 m), 1.97 wt. % (1.2 m), (5) $MoS_2$ for each cut-off grade(0.01%, 0.1%); an weighted average grade 0.15 wt. % (6.3S m), 0.28 wt. % (3.15 m), (6) $Ta_2O_5$ for each cut-off grade (0.01%, 0.1%); an weighted average grade 0.13% (19.S m), 1.11% (1.8 m), (7) $Nb_2O_5$ for each cut-offgrade (0.01%, 0.1%); an weighted average grade 0.06% 11.5 m), 0.15% (3.0 m).

• Journal of the Korean Society of Clothing and Textiles
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• v.31 no.2 s.161
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• pp.292-299
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• 2007

Development of portable device measuring the vital sign continuously with no limit of time and space is absolutely prerequisite for the U-health care that grafts the ubiquitous concept into medical system. Accordingly, it requires to develop a garment style apparatus for measuring vital-sign that is easy to wear on for a long time period. This study suggests a method to improve the insulation of electric cable and the skin adhesion of electrode by integrating the electric conductive material to garment, in order to develop a garment apparatus for measuring ECG for U-health care. Results of the research are as follows; In order to provide the adjacent conductive yarns with insulation, braid with narrow woven end was interlaced using polyester yarn. As a result, the direct contact between electric conductive yarns was restrained, which would be interposed into pin-tuck structured cable. Washable silicone gel applied around the electrode made of electric conductive fabric improved the adhesion, which prevents electrodes from dropping off from the skin surface during body movement. ECG signals on the human subject were tested using the garment apparatus developed by the above method. And the result was that the clear QRS wave formation in the typical form of ECG could be measured in both conditions of still and moving state as well. The result of this study is expected to contribute for the production of U-health care related medical apparatus by accelerating the practical uses of the garment measuring vital sign at a reasonable price.

• Korean Journal of Applied Biomechanics
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• v.26 no.2
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• pp.161-166
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• 2016

Objective: The purpose of this study was to determine the knee and ankle joint kinematics and kinetics by comparing downhill walking with valley-shape combined slope walking. Method: Eighteen healthy men participated in this study. A three-dimensional motion capture system equipped with eight infrared cameras and a synchronized force plate, which was embedded in the sloped walkway, was used. Obtained kinematic and kinetic parameters were compared using paired two-tailed Student's t-tests at a significance level of 0.05. Results: The knee flexion angle after the mid-stance phase, the mean peak knee flexion angle in the early swing phase, and the ankle mean peak dorsiflexion angle were greater during downhill walking compared with valley-shape combined slope walking (p < 0.001). Both the mean peak vertical ground reaction force (GRF) in the early stance phase and late stance phase during downhill walking were smaller than those values during valley-shape combined slope walking. (p = 0.007 and p < 0.001, respectively). The mean peak anterior GRF, appearing right after toe-off during downhill walking, was also smaller than that of valley-shape combined slope walking (p = 0.002). The mean peak knee extension moment and ankle plantar flexion moment in late stance phase during downhill walking were significantly smaller than those of valley-shape combined slope walking (p = 0.002 and p = 0.015, respectively). Conclusion: These results suggest that gait strategy was modified during valley-shape combined slope walking when compared with continuous downhill walking in order to gain the propulsion for lifting the body up the incline for foot clearance.

• Physical Therapy Korea
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• v.18 no.3
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• pp.26-37
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• 2011

Although there have been various studies related to the body's movement from a sitting to a standing position (sit-to-stand task), there is limited information on the kinematic changes on the frontal and transverse planes. The purpose of this study was to ascertain how pelvic tilt affects kinematic changes in the frontal and transverse planes in the hip and knee joints during a sit-to-stand task. For this study, 33 healthy participants (13 female) were recruited. Each participant rose from a sitting to a standing posture at his or her preferred speed for each of three different pelvic tilt trials (anterior, posterior, and neutral), and the measured angles were analyzed using a 3-D motion analysis system. A one-way repeated measure analysis of variance was performed with Bonferroni's post hoc test. In addition, an independent t-test was carried out to determine the sex differences in hip and knee joint kinematic changes during the sit-to-stand tasks. The results were as follows: 1) The hip and knee joint angle in the frontal and transverse planes showed a significant difference between the different pelvic tilt postures during sitting in the pre-buttock lift-off phase (pre-LO) (p<.05). Compared to the posterior pelvic tilt posture, the anterior pelvic tilt posture involved significantly greater hip joint adduction and internal rotation, knee joint adduction, and reduced internal rotation of the knee joint. 2) Sex differences were found with significant differences for males in the initial and maximal angles in the frontal plane of the hip and knee joint (p<.05). Females had a significantly smaller initial abduction angle of the hip joint and a significantly greater maximal angle of the hip adduction joint. These results suggest that selecting a sit-to-stand exercise for pelvic tilt posture should be considered to control abnormal movement in the lower extremities.