• Transactions of the Korean Society of Automotive Engineers
• /
• v.8 no.4
• /
• pp.121-129
• /
• 2000

this paper develops a computational model for the turning maneuver analysis of a cabover type heavy truck. The model having 42 degree-of-freedom is developed using ADAMS. Leaf springs used in the front and rear suspension systems are modeled by dividing it three links and joining them with joints. Force and displacement relationship showing nonlinear hysteric characteristics of the leaf spring is measured and modeled with an exponential function. A velocity and force relationship of a shock absorber is measured and modeled with a spline function. And a stabilizer bar is modeled using ADAMS beam element to consider a twisting and bending effect. To verify the developed model an actual vehicle test is performed in the double lane change course with 50kph and 60kph vehicle velocity. In the actual vehicle test lateral acceleration roll angle and yaw rate are measured, The tendency and peak-to-peak values of the actual vehicle test and simultion results are compared each other.

• Proceedings of the Korean Fiber Society Conference
• /
• 2003.10a
• /
• pp.77-78
• /
• 2003

The surface evenness and texture of textile products are closely related with the irregularity of yarn thickness which has an important role to influence the quality and the process efficiency. For measuring yam thickness the capacitive method is known to dominate the market, delivering results that are in a close relation with the mechanical properties of yarn, while the optical method offers information that seems related rather with the apparent quality of yarn. If a thin light beam is applied for the optoelectrical measurement, it is very possible that this method can provide us with important information which is not obtainable from the capacitive type measurement. This paper reports the results of a study about the yarn thickness and its variation on the basis of a new measurement system using a laser slit beam. Analysis of the new system confirms that we can extract new information on the yarn irregularity ranging into much short wavelengths. Even the visual shade created by the yam doubling and twisting can be measured and represented well. Depending on the yam types, the thickness measurements show their own characteristics.

• Proceedings of the KSME Conference
• /
• 2007.05a
• /
• pp.1617-1620
• /
• 2007

This paper presents a magnetostrictive transpositioner and its fabrication process. To get a transposition movement without shifting or twisting, it is designed as an array type. To fabricate the suggested design, micromachining and selective DC magnetron sputtering processes are combined. TbDyFe film is sputter-deposited on the back side of the bulk micromachined transpositioner, with the condition as: Ar gas pressure below $1.2{\times}10^{-9}$ torr, DC input power of 180W and heating temperature of up to $250^{\circ}C$ for the wireless control of each array component. After the sputter process, magnetization and magnetostriction of each sample are measured. X-ray diffraction studies are also carried out to determine the film structure and thickness of the sputtered film. For the operation, each component of the actuator has same length and out-of-plane motion. Each component is actuated by externally applied magnetic fields up to 0.5T and motion of the device made upward movement. As a result, deflections of the device due to the movement for the external magnetic fields are observed.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.19 no.5
• /
• pp.100-112
• /
• 2011

This paper studied on a theoretical approach to predict structural performances and weight -reduction rates of hybrid bodyshells in case that the material of underframe structure is substituted. To choose other light-weight materials to be substituted for the original underframe material, compressive, bending and twisting deformations are considered under constant stiffness and strength conditions, which derive some new weight-reduction indices from a structural performance point of view. Next, these weight-reduction indices were verified using the finite element analyses of some simplified examples. It is shown that the derived indices to estimate the weight-reduction can be utilized as a good criterion for material substitution of the underframe at a basic design stage.

• Journal of architectural history
• /
• v.25 no.6
• /
• pp.81-88
• /
• 2016

The purpose of this study is to inquire original design and character of dancheong in Yeongnamnu P avilion which features unusual portraits of twisting dragons and four heavenly creatures. Its artistic value and originality can be found in the portraits of four heavenly creatures which are painted on the interior seonjayeon(fan shape rafter) and in the unique design of crossbeam meoricho(flower decorations on each side of pillars). Yeongnamnu's crossbeam meoricho is janggu-meoricho type(meoricho with hourglass figure) with full-shape lotus and half-shape flower decorations. And it can be said that, dragon portrait painted on the border of lotus and flower decorations in green and yellow is a very unique style of dancheong, for the reason that it has scarcely been used before and ever since. The portrait of four heavenly creatures painted on each corner of seonjayeon is also found to be unique in design, for the reason that the design has rarely been used throughout history, with only two exceptions in mural tombs of Goguryeo and folding screen in Injeongjeon Hall of Changdeokgung P alace. With its unique and authentic feature along with its rarity in number, the portrait of four heavenly creatures painted on Yeongnamnu can be considered as quite symbolic and important.

• Journal of Korean Orthopaedic Sports Medicine
• /
• v.5 no.2
• /
• pp.141-146
• /
• 2006

Purpose: This study was performed to analyze the mechanism and type of knee injury during soccer game and to evaluate the functional recovery after treatment. Materials and Methods: From October 2002 to January 2005, 49 patients were treated surgically. Mean age was 28.8 (8-36) years old, mean follow-up duration was 14.9 (8-36) months. Injury was evaluated by physical examination, radiography, and arthroscopic finding. Clinical results were evaluated with Lysholm score and Tegner activity score. Results: According to classification of the ligament injury, the incidence of single ACL injury was the most frequent and 27 cases. Injuries took place, in 2nd half of the games, and in the winter. Among the mechanism of injury, turn & twisting was 20 cases and the most frequent. The preoperative Lysholm score, Tegner activity score were 45, 2 and those of last follow-up were 87.6, 6, respectively. Conclusion: The recovery of Lysholm and Tegner activity score were good, but the sports activity was clearly decreased alter injury. It was suggested that appropriate physical & psychological rehabilitation and education were inevitable.

• Korean Journal of Oriental Medicine
• /
• v.3 no.1
• /
• pp.215-228
• /
• 1997

Extrapyramidal movement disorders are divided descriptively into hypokinesias(such as parkinsonism), characterized by poverty and slowness of movement : hyperkinesias(such as chorea, athetosis, dystonia, ballism, etc.), manifested by abnormal involuntary movement. Chorea refers to widespread arrythythmic movements of a forcible, rapid, jerky, restless type Choreic movements are noted for their irregularity and variability. They are generally continuous, may be simple or quite elaborate, and affect any part of the body. Dystonla refers to abnormally increased muscular tone that causes fixed abnormal postures. Some patients with dystonia also have shifting postures, resulting from irregular, forceful twisting movement that affect trunk and produce bizarre, grotesque movements and positions of the body. The most frequent and familiar type of focal dystonia is spasmodic torticollis. It consists of an involuntary turning of the head to one side - intermittent at first, then gradually worsening to the point of being more or loss continuous. The combination of blepharospasm and oromandibular dystonia is sometimes refered to as Meige's syndrome. We report two patients with dystonia and chorea in cerebral infarction at basal ganglia. We have experienced good improvement by the oriental medicine and acupuncture treatment.'rho acupuncture points of LI 4, ST 36, TE 3, GB 34, GB 41, LR 3, GB 39 were used. The therapies of herb-medicine were treated by Zibu-Ganshen(滋補肝腎), Huoxue-Xifeng-Tongluo(活血息風通絡).

• Journal of Korean Association for Spatial Structures
• /
• v.12 no.1
• /
• pp.69-75
• /
• 2012

The purpose of this paper is to study comparative analysis of cable dome structures by reinforcement effect with bracing and fabric. Tensegrity systems are stable structures which are reticulated spatial structures composed of compressive straight members, struts, and cables. Tensegrity structures need to be introduced to the initial stress for the self-equilibrated system to have a stable state. In this paper, the effect of reinforcement resisting the in-plan twisting is investigated for the Geiger-type and Zetlin-type models reinforced by bracing and fabric. The effect of initial imperfection is also studied because the structural instabilitity phenomenon of shell-like structures is very sensitive according to the initial condition. We study a more exact analysis concerning the structural instability of tensegrity structures using nonlinear analysis program. Then, two types of tensegrity models will be analysed and compared.

• Journal of the Korean Society for Precision Engineering
• /
• v.30 no.1
• /
• pp.39-46
• /
• 2013

Smart material such as SMA (Shape Memory Alloy) has been studied in various ways because it can perform continuous, flexible, and complex actuation in simple structure. Smart soft composite (SSC) was developed to achieve large deformation of smart material. In this paper, a shell actuator using woven type SSC was developed to enhance stiffness of the structure while keeping its deformation capacity. The fabricated actuator consisted of a flexible polymer and woven structure which contains SMA wires and glass fibers. The actuator showed various actuation motions by controlling a pattern of applied electricity because the SMA wires are embedded in the structure as fibers. To verify the actuation ability, we measured its maximum end-edge bending angle, twisting angle, and actuating force, which were $103^{\circ}$, $10^{\circ}$, and 0.15 N, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.06a
• /
• pp.480-480
• /
• 2008

Vacuum circuit breaker(VCB) is now emerging as an alternative of gas circuit breaker(GCB) which uses SF6 gas as insulating material whose dielectric strength is outstanding. But we have to reduce SF6 gas because SF6 gas is one of greenhouse gas and efforts to reduce greenhouse gas are now trend of the world. Therefore, we can say VCB is the optimal alternative of GCB because vacuum is environmentally friendly. The vacuum interrupter is the core part of VCB to interrupt arcing current. There are mainly two methods to extinguish arc. One is radial magnetic field (RMF) method and the other is axial magnetic field (AMF) method. We deals with RMF method in this paper. Compared with AMP, RMF arc quenching method has different principle to extinguish arc. In case of RMF method, pinch effect is much larger than AMF method. Because of pinch effect RMF type contact electrodes have the single large spot which is severly damaged and melted while AMF type contact electrodes have small and multiple spots which are slightly damaged and melted. To prevent contact electrode being damaged and melted from high temperature-arc, RMF method uses Lorentz force to move arc. In this paper we calculated and compared the arc driving force of two cases and we analyzed the force acting on each part of arc by means of commercial finite element method software Maxwell 3D. They have 3petals and we considered two cases. One is the case when fixed(upper) and movable(lower) contacts are in mirror arrangement (Case 1). The other is the case when one of two contacts (movable contact) is revolved at maximum angle as possible as it can be (Case 2). And at each case above, we analyzed arc driving force at two positions, position 1 is the closest to the center of contact and position 2 is near the edge of petal on fixed contact. As a result we could find that Case 2 generated stronger arc driving force than Case 1 at position 1. But at position 2 Case 1 generated stronger arc driving force than Case 2. This simulation method can contribute to optimizing spiral-type electrode designs in a view of arc driving force.