• Journal of Physiology & Pathology in Korean Medicine
• /
• v.18 no.1
• /
• pp.250-253
• /
• 2004

The effects of crude extracts from medicinal plants on biological activity were investigated. The crude ethanol extract of H. paucistipula inhibited the growth of the Gram positive bacterium Bacillus subtilis ATCC 19659, (2 mm inhibition zone at 150 ㎍/disc) and the dermatophyte Trichophyton mentagrophytes ATCC 28185, (7 mm inhibition zone at 150 ㎍/disc), and toxic to P388 murine leukaemia cells ATCC CCL 46 P388D1, (IC/sub 50/ 2.48 ㎍/㎖ at 75 ㎍/disc). This crude ethanol extract of H. paucistipula is the strongest antimicrobial and cytotoxic activities against P388 murine leukaemia cells ATCC CCL 46 P388D1.

• Transactions of The Korea Fluid Power Systems Society
• /
• v.7 no.1
• /
• pp.20-27
• /
• 2010

Electromagnetic control valves have been used for almost 20 years. As the solenoid modulating technology advances, its applications are extending to various industrial fields such as nuclear and fossil fuel power plants, chemical plants and refineries. Proportional solenoid valve for large flow control is designed with two-stage configuration to meet the required actuating force on the main disc and its position is stabilized by the self-controlled system. In this research, main disc dynamics is analyzed with linearized system model which is derived from the mathematical equations describing its nonlinear behavior. Major design parameters of the valve control system that affect the response and stability are also studied with root locus method. The linear dynamic analysis results are verified with simulations in time-domain.

• Journal of Advanced Marine Engineering and Technology
• /
• v.36 no.3
• /
• pp.358-367
• /
• 2012

A study on tidal turbine using CFD simulation has been an economical and reliable method. However, large flow fields with multi-turbine arrays require high computer performance. Actuator disc theory therefore is widely applied. Actuator disc is the concept that imitates actual turbine by means of an energy absorption disc which has the same dimension and characteristics. Turbines installed in array may have disturbance effects on one another. Thus, the subject of this study is to analyze the far wake of these tidal turbines and compare to single turbine case. The main objects are to analyze two turbines positioned longitudinally at different spaces.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2006.05a
• /
• pp.383-384
• /
• 2006

Ventilated disc was improved for reducing judder and heat. But the crack among vent holes occurs due to stress concentration. We investigate the stress distribution of vent holes. The vent holes with shape of a right angle, a chamfer and rounding was analyzed. The result of FEA was that rounded vent holes have a minimum stress. Also Maximum stress distributed within holes. Therefore We suggest that the rounded vent holes is good to reduce the crack.

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2006.09a
• /
• pp.629-630
• /
• 2006

To investigate sliding friction and wear behaviors of WC-Co/WC-Co pairs containing different WC grain sizes, the ball-on-disc test in air were carried out, where WC grain sizes a $0.5\;{\mu}m$ (F.G.) and $1.5\;{\mu}m$ (C.G.). The wear volume of F.G. pin for F.G. pin/C.G. disc is larger than that of F.G. pin for F.G. pin/F.G. disc due to higher friction coefficient, and the surfaces after wear test are richer in oxygen compared to those before test. Furthermore, the wear debris, which is composed of nona-scale grain, after the wear test are remarkably richer in oxygen than to those before test.

• Proceedings of the KSR Conference
• /
• 1999.11a
• /
• pp.259-266
• /
• 1999

A study on the static type train simulator will include the training of new drives requires that the environment of the cab, controls placement, etc. must highly realistic so that driver can readily transfer his training experience to the real world. The simulator computer sends video disc speed command to a Video PC processor. A video switcher select the output of the on-line player. This selection is done with loss of vertical synchronization, meaning the picture will not noticeable roll or jump as the simulation mover from disc to disc. The video image quality remain contestant through the simulated speed range from zero to 100km/h. Flicker is avoided in the scene by the use of a TBC(Time Base Corrector) which causes the display of one video field at a time. Thus, no interfield jitter is present when the scene is stopped.

• Applied Biological Chemistry
• /
• v.23 no.1
• /
• pp.14-22
• /
• 1980

White and black sesame produced in Korea were defatted with ethyl ether or n-hexane. Defatted sesame meal was extracted with water and salt solution, and protein extraction was precipitated at various pH 1 through 12, with trichloro acetic acid (TCA), tannic acid and ammonium sulfate, respectively. Protein was purified by Sephadex A-25, G-75, G-100 and G-200, and identified its protein fraction by polyacrylamide gel electrophoresis. Amino acids composition of protein in white sesame was analyzed by automatic amino acid analyzer. Protein contents of white sesame, black sesame and sesame meal are 20.5%, 19.2%, and 44.7%, respectively. n-Hexane was the most suitable solvent for extraction of oil from sesame. Crude protein precipitation was better in higher pH. The protein extraction was more effective with the solution containing sodium chloride tinder the pH 8. Globulin in total protein was high and prolamin was less than in other cereal proteins. Glutamic acid contents of white sesame and sesame globulin were 17.1%, and 20%, respectively. Both proteins contained relatively high levels of essential amino acids. 12-13 bands were found in water soluble protein and 2 bands in salt soluble protein were detected by the disc gel electrophoresis, and were identified in both of white and black sesame. The salt soluble protein of white sesame could be purified by Sephadee G-100 and G-200.

• The Journal of Korea CHUNA Manual Medicine
• /
• v.2 no.1
• /
• pp.93-109
• /
• 2001

Objectives : The aim of present study is to estimate clinical outcome of Chuna treatment and Chuna medicine treatment for patients with H.I.V.D(Herniated Intervertebral Disc) of lumbar spine according to the character of patients and the steps of Chuna therapy, and therefore suggest a prospective, desirable Chuna treatment and patient guidance. Methods : We investigated the 258 cases of outpatients who were diagnosed as the H.I.V.D. on lumbar C.T. or MRI and were treated more than seven times with chuna treatment and more than one time with Chuna medicine treatment In Jaseng Oriental Medicine Hospital from September 1, 1999 to December 31, 2000. We evaluated the subjective symptoms by Hudgin's classification. For the sake of the more objective evaluation for before and after treatment, we calculated the Improvement index and ratio of the four parts to estimate the pain and functional disorder In before and after treatment by Macnab's criteria. Results & Conclusion : The improvement index and ratio showed that the conservative therapy with Chuna therapy improved the symptom of H.I.V.D. much effectively, and especially in the patient groups of male, 30-39 years, standing Job, duration of symptom within one week, the 4th step of chuna treatment, the first step of chuna medicine treatment, and the excellent satisfactory assessment of Chuna treatment. Therefore, it is supposed that the conservative therapy with Chuna therapy and patient guidance should be much actively continued.

• Journal of Korean Neurosurgical Society
• /
• v.45 no.3
• /
• pp.169-175
• /
• 2009

Objective : The goal of this study was to evaluate the biomechanical features of human cadaveric spines implanted with the Activ L prosthesis. Methods : Five cadaveric human lumbosacral spines (L2-S2) were tested for different motion modes, i.e. extension and flexion, right and left lateral bending and rotation. Baseline measurements of the range of motion (ROM), disc pressure (DP), and facet strain (FS) were performed in six modes of motion by applying loads up to 8 Nm, with a loading rate of 0.3 Nm/second. A constant 400 N axial follower preload was applied throughout the loading. After the Activ L was implanted at the L4-L5 disc space, measurements were repeated in the same manner. Results : The Activ L arthroplasty showed statistically significant decrease of ROM during rotation, increase of ROM during flexion and lateral bending at the operative segment and increase of ROM at the inferior segment during flexion. The DP of the superior disc of the operative site was comparable to those of intact spine and the DP of the inferior disc decreased in all motion modes, but these were not statistically significant. For FS, statistically significant decrease was detected at the operative facet during flexion and at the inferior facet during rotation. Conclusion : In vitro physiologic preload setting, the Activ L arthroplasty showed less restoration of ROM at the operative and adjacent levels as compared with intact spine. However, results of this study revealed that there are several possible theoretical useful results to reduce the incidence of adjacent segment disease.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.18 no.5
• /
• pp.558-563
• /
• 2008

Vibration/shock affects biggest taking a train subtraction of vehicle and durability decline. Therefore, absorber is used for vibration/shock isolation and various qualities of the material and design are applied to isolation. This paper proposes vibration/shock absorber that applies 'Disc' spring. Through comparison with 'Disc' spring that has nonlinearity and coil spring that is having linearity, see effect that nonlinearity of isolation gets in vibration/shock Isolation. Coil spring and 'Disc' spring are non-linear numerical analysis and simulation through theory for this, get and investigate comparison result through an experiment finally. Expressed and formulated shock through 'Runge-Kutta' method/impact response to nonlinear-vibration-equation of 1 degree of freedom for numerical analysis. Double half sine pulse of excitation used and analyzed result through spectrum response analysis here. Response of disc spring is compared to response of coil spring by changing $h_o/t$ ratio with computer simulation and the usage of disc spring is increased through analysis of effect of design factors. The purpose of this paper is that the shock response of disc spring is calculated through numerical simulation and to design the optimal absorber under the limited condition. And then, the isolation effect was analyzed through the shock test.