• Journal of the Korean Society for Precision Engineering
• /
• v.19 no.5
• /
• pp.110-117
• /
• 2002

This paper proposes a optimization of the design variables of linear motor for the improvement of thrust. Especially, this paper treats the shoe, which can be good to flow of a magnetic flux in linear motor. Firstly, this paper uses a space harmonic analysis method(SHAM) based on Fourier series, for analyzing the characteristics of core type linear motor, including slot structure and shoe. And compare the magnetic flux densities of linear motor at air gap with the results of the SHAM and the Finite Element Method(FEM). Secondly, this paper uses a genetic algorithm, which is good to find the global solutions. The design variables are the pole pitch of magnet, the pitch of slot, the height of slot, the width of shoe and the width of magnet. The maximum thrust with optimum design variables is about 247 N which is improved about 16%.

• Archives of Plastic Surgery
• /
• v.32 no.5
• /
• pp.663-666
• /
• 2005

Mandible angle ostectomy is the most widely-operated facial contour surgery. We experienced a rare case of necrotizing fasciitis of the lower leg following mandible angle ostectomy. A 20 years old female visited our department 5 days after mandible angle ostectomy. At the time, she was diagnosed as sepsis and on her 2nd admission day, she was diagnosed as necrotizing fasciitis on her left leg. She was treated by fasciotomy and necrotized tissue removal. Necrotizing fasciitis is a rare complication of any kinds of operation but once it develops, it causes fatal results, especially to cosmetic surgeries. Early diagnosis and aggressive operation is known as only treatment for the disease.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.26 no.2
• /
• pp.147-154
• /
• 2012

Hwanggeum-tang (HGT) was recorded in Dongeuibogam as being able to treat Sogal whose concept had been applied to Diabetes Mellitus (DM). Advanced glycation end products (AGEs) play important roles in the development of diabetic complications such as atherosclerosis by eliciting inflammatory responses. In this study, we examined the suppressive effects of HGT against inflammation elicited by AGEs. AGEs treatment increased the expression of pro-inflammatory cytokine gene TNF-${\alpha}$; chemokines MCP-1, IP-10; pro-inflammatory cyclooxygenase COX-2 on the THP-1 cells. HGT had suppressed the expression of pro-inflammatory genes and protein levels in AGE-treated THP-1 cells. HGT had also decreased intracellular ROS production stimulated by AGEs. These results suggest that HGT has beneficial effects for the improvement diabetic vascular complication through suppressing inflammatory responses elicited by AGEs.

• Journal of the Korean Society for Precision Engineering
• /
• v.29 no.1
• /
• pp.64-71
• /
• 2012

In this paper, a parallel manipulator is comprised of two sliders and four links. Sliders execute a linear reciprocating motion depending on parallel guides and make the connected links rotate. A couple of links connected by sliders do coupling motion. The end-effector called a link tip has orientation angle. Through the kinematics analysis of this manipulator, we found displacement, velocity and acceleration using direct and inverse kinematics. We used equations that derived from this analysis and determined five constraint conditions. These conditions had much to do with rotation states of links, the relative relation of link length and coupling motion state. To verify those, we suggest a new algorithm regarding constraint conditions of a manipulator. With the result which performed the algorithm, we found out that operation range of coupled links was limited by relative relation of link length and that manipulator was not able to carry out a series of link motion, in case of being the link vertical between two parallel guides.

• Journal of the Korean Society for Precision Engineering
• /
• v.31 no.10
• /
• pp.897-904
• /
• 2014

In this paper, two-DOF parallel manipulator has the sliders which execute a linear reciprocating motion depending on parallel guides and the end-effector which can be adjusted arbitrarily. To investigate the dynamic characteristics of the manipulator, the dynamic performance index is used. The index is able to be obtained by the relation between the Jacobian matrix and the inertia matrix. The kinematic and the dynamic analysis find these matrices. Also, the dynamic model of the manipulator is derived from the Lagrange formula. This model represents complicated nonlinear equations of motion. With the simulation results of the dynamic characteristic of the manipulator, we find that the dynamic performance index is based on the selection of the ranges for the continuous movement of the manipulator and the dynamic model derived can be used to the control algorithm development of the manipulator.

• The Korean Journal of Pain
• /
• v.26 no.3
• /
• pp.286-290
• /
• 2013

Air injected into the epidural space may spread along the nerves of the paravertebral space. Depending on the location of the air, neurologic complications such as multiradicular syndrome, lumbar root compression, and even paraplegia may occur. However, cases of motor weakness caused by air bubbles after caudal epidural injection are rare. A 44-year-old female patient received a caudal epidural injection after an air-acceptance test. Four hours later, she complained of motor weakness in the right lower extremity and numbness of the S1 dermatome. Magnetic resonance imaging showed no anomalies other than an air bubble measuring 13 mm in length and 0.337 ml in volume positioned near the right S1 root. Her symptoms completely regressed within 48 hours.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.26 no.7
• /
• pp.1232-1240
• /
• 2002

Recently, linear motors are applied to many small precision products. Thus high generating power with small size is required of it. In order to increase the motor efficiency, the design variables need to be optimized. In this study, Vector Fields FEM software, OPERA-3d, was used for simulating linear motor. The thrust and magnetic flux density at the air-gap center were simulated and compared with the experimental results. Taguchi method was applied to investigate the effects of each variables. As a result, the thickness of conductor and magnet was important for the thrust but the thickness of the yoke. The temperature of the conductor was determined by finding the thermal conductivity that was determined by experimentation. Correlation equation relating to the thrust and temperature was proposed by Latin square and Least Square method. The optimum design variables were determined by correlation equation, and compared with simulation results. According to this analysis, thrust force of linear motor was improved about 7% comparing with conventional model.

• Food Science of Animal Resources
• /
• v.30 no.4
• /
• pp.545-550
• /
• 2010

The effects of casein hydrolysate on blood pressure (BP) and serum lipid profiles were investigated in spontaneously hypertensive rats (SHR). Twenty-four 6-wk old male SHRs were assigned to 3 groups in a completely randomized design. Experimental groups were as follow: control, market milk group (MLG) and casein hydrolysate group (CHG). Reference blood pressure (RBP) showed average $198.94{\pm}1.46mmHg$. Blood pressure (BP) of CHG reduced 24 mmHg after 2 wk of treatment, but these increased after 3 wk. BP of CHG was significantly lower than BP of Control in experimental time (p<0.05). Serum lipid profiles were not differ significantly among groups (p<0.05). These data suggest that casein hydrolysate may beneficially improvement of blood pressure level in SHR.

• Journal of Mechanical Science and Technology
• /
• v.18 no.12
• /
• pp.2209-2215
• /
• 2004

In the present research work, an automated machine vision system and a new algorithm to interpret the inspection data has been developed. In the past, the control of tolerance of front-chassis-module was done manually. In the present work a machine vision system and required algorithm was developed to carryout dimensional evaluation automatically. The present system is used to verify whether the automobile front-chassis-module is within the tolerance limit or not. The directional ability parameters related with front-chassis-module such as camber, caster, toe and king-pin angle are also determined using the present algorithm. The above mentioned parameters are evaluated by the pose of interlinks in the assembly of an automobile front-chassis-module. The location of ball-joint center is important factor to determine these parameters. A method to determine the location of ball-joint center using geometric features is also suggested in this paper. In the present work a 3-D best fitting method is used for determining the relationship between nominal design coordinate system and the corresponding feature coordinate system.

• Textile Coloration and Finishing
• /
• v.22 no.1
• /
• pp.51-60
• /
• 2010

This research works on the effects of drawing conditions on the physical properties of the drawn worsted yarns. The drawn worsted yarns were made by the yarn drawing system under various drawing conditions such as concentration of reducing agent, draw ratio, setting time of drawn yarn, and concentration of oxidizing agent. The drawn worsted yarns from 2/80Nm to 2/90Nm were obtained from 2/60Nm worsted yarns, the surface and cross-sectional shapes and tensile properties of these various specimens were measured and discussed with the various drawing conditions. The drawing of worsted yarn made constituent wool fiber scratched and made it changing to polygonal cross-sectional shape. The tenacity and modulus were increased with draw ratio and concentration of reducing agent. And tensile strain was increased with draw ratio, which decreased with concentration of reducing agent.