• The Journal of Korean Obstetrics and Gynecology
• /
• v.19 no.2
• /
• pp.127-140
• /
• 2006

Purpose : This study was conducted to investigate the antimicrobial effects of Astringent medicinals against vaginal microbe. Methods : Staphylococcus aureus, Methicillin-resistant Staphylococcus aureus, Candida albicans and Gardnerella vaginalis were used for vaginitis-induced microbe. Lactobacillus gasseri, Streptococcus spp. and Escherichia coli HB101 were used for normal vaginal florae. And Astringent medicinals (Rubi Fructus, Tritici Immatri Semen, Corni Fructus, Nelumbinis Semen, Mume Fructus, Schizandrae Fructus, Ailanthi Radicis Cortex, Galla Rhois, Myristicae Semen, Terminariae Fructus, Rosae laevigatae Fructus, Ephedrae Radix) were used in this study. Antimicrobial activities were tested by optical density and colony test in vitro. And then wee valuated the antimicrobial effects in comparison with optical density and colony test. Results : The optical density and colony test showed that Terminariae Fructus and Galla Rhois among Astringent medicinals had the antimicrobial effects. Teminariae Fructus had the antimicrobial susceptibility and selective toxicity against Candida albicans and Gardnerella vaginalis of vaginitis-induced microbe. Galla Rhois had the antimicrobial susceptibility and selective toxicity against Staphylococus aureus, Methicillin-resistant Staphylococus aureus, Candida albicans and Gardnerella vaginalis of vaginitis-induced microbe. Conclusion : According to these results, we can suggest that Terminariae Fructus and Galla Rhois among Astringent medicinals be available to the antimicrobial agent of vaginitis-induced microbe in vitro.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.15 no.1
• /
• pp.116-124
• /
• 2007

An optical method to measure the size and number density of soot aggregates in diesel exhaust has been proposed in this study. Two laser beams in co-axial alignment transmit a soot loaded exhaust gas flow, and the transmittance at each wavelength is detected by a photo diode simultaneously. The volume equivalent diameter and number density of soot aggregates in the optical path can be theoretically given by the transmittance values measured at two wavelengths. A test conducted by a single cylinder, 4 cycle, small and DI diesel engine shows that the temporal variations of the size and number density of soot aggregates in the diesel exhaust can be measured by the proposed method at a transient mode operation. It is found that the volume equivalent diameter varied temporally from 70 to 110 nm during the period that high soot concentration is observed. One can also conclude that the optical length longer than 1 m in the dynamic range regarding this method is preferable for measuring soot concentration at the level of $1\;mg/m^3$.

• Proceedings of the KSME Conference
• /
• 2001.06c
• /
• pp.445-450
• /
• 2001

DVD(Digital Versatile Disk) is the data storage media devised to make high storage density and high data input/output possible. Therefore higher rotational speed and better accuracy in optical pick-up are required compared with the existing optical storage device. These operational functional requirements are concerned with abilities of optical storage device. Especially, High rotational speed is deeply concerned with the noise and vibration of optical storage device, is important problem in development of optical storage device so much. This paper propose a new concept ROM media of optical storage device named as Cylindrical ROM media, and evaluate this by means of Axiomatic approach and empirical data.

• Journal of Korean Society for Quality Management
• /
• v.26 no.4
• /
• pp.250-264
• /
• 1998

The purpose of the thesis is to develop simulation program for forecasting of optical connector. So we can achieve the time and the money saving for making the optical connector. Optical performance (insertion loss) of optical connector mainly relies on 3 misalignment factors-ferrule factor due to mis-manufacture from design, auto-centering effect that is fiber behavior phenomena between hole and fiber, fiber misalignment factor. Simulation use experimental data with auto-centering effect and fiber factor and use pseudo data with ferrule through random number generation because it is developing stage. In this study we a, pp.y kernel density estimation method with experimental data in order to know whether it belong to or not specific parametric distribution family. And we simulate to forecast insertion loss of optical multifiber connector under specific design model using nonparametric bootstrap resampling data and parametric pseudo samples from uniform distribution. We obtain the tolerance specifications of misalignment factors satisfying not exceed in maximum 1.0dB and choose optimal hole diameter.

• Korean Journal of Optics and Photonics
• /
• v.15 no.1
• /
• pp.51-55
• /
• 2004

Surface plasmons (SPs) are charge density oscillations that propagate along an interface between a dielectric and metal. In this paper, the electric field of SPs and the intereference of two SPs are observed by using Near-field Scanning Optical Microscope (NSOM). The excitation condition of SPs is changed as the optical tip approaches the metal surface, because the excitation condition of SPs is very sensitive to surface structures. To measure the microscope field of SPs, the distance between metal surface and optical tip must contain a specific interval.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2004.05a
• /
• pp.888-893
• /
• 2004

This paper proposed a dual actuator using bimorph PZT for information storage device based on prove array NSOM(Near-field Scanning Optical Microscopy). The gap between the media and the optical head should be maintained within the optical tolerance. Therefore, a new actuator having high sensitivity is required. Bimorph PZT, which has fast access time and high sensitivity characteristic, is suitable for this precise actuating system. This paper is focused on derivation of mathematical model of dual bimorph PZT actuator and control algorithm. Hamilton's principle was used for mathematical model. The model is verified by FEA(Finite Element Analysis), and compared with experimental results. Different control algorithms were used f3r two bimorph PZT actuating same direction and opposite direction. The gap between recording media and optical head was controlled within 20nm in experiment.

• Applied Science and Convergence Technology
• /
• v.23 no.5
• /
• pp.211-220
• /
• 2014

In this paper, we present a review of optical and structural studies of $GaBi_xAs_{1-x}$ epilayers grown by Molecular Beam Epitaxy (MBE) on (311)B and (001) GaAs substrates with different As fluxes. The results indicate that under near-stoichiometric conditions the bismuth incorporation is higher for samples grown on (311)B GaAs substrates than for those grown on (001) GaAs. In addition, carrier localization effects in GaBiAs layers are clearly revealed for both samples by optical measurements. The (311)B samples showed evidence of higher density of defects. It has also been found that the nonradiative centers play a significant role in the recombination process in this material system. The influence of post-growth annealing on the microstructural, optical, and magneto-optical properties was also investigated. An important improvement of optical and spin properties after thermal annealing due to the reduction of defects in the GaBiAs layers was observed.

• Electrical & Electronic Materials
• /
• v.7 no.3
• /
• pp.220-224
• /
• 1994

In this study, we discussed the optical property to find the optimal condition of Te-based antireflection trilayer(ART) structure for a high density optical recording. It was found that the optical property was improved by suggesting the environmental parameters satisfied the optimum condition. As the results, the optimized(.lambda.=8.000${\AA}$.) thickness of the recording layer is 27${\AA}$, and the 1st and 2nd minimum ART conditions of dielectric layers are 1080${\AA}$, 3820${\AA}$, respectively. And the high SNR, the contrast ratio and the sensitivity are achieved by using the ART conditions.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.9
• /
• pp.149-158
• /
• 1999

The modern trends of optical storage devices can be characterized by high density in information recording, and high bandwidth in data input/output processing rate. These make servo engineers to face with a new barrier on control system design in much more difficult way. The first step to attack this barrier will be through a systematic modeling for the dynamic characteristics of optical storage drive. in this paper, an analytical dynamic model for an optical storage drive based on FEM is drived, and compared with experimental results. Through this comparison, a practical dynamic model on the focusing and tracking motion of optical storage drive is proposed for the initiation of real control system design problem.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.23 no.11 s.170
• /
• pp.2050-2057
• /
• 1999

It is necessary to improve mechanical and optical properties in the optical disk substrates as the information storage devices with high storage density using short wavelength laser are being developed. Injection compression molding is regarded as the most suitable process to manufacture optical disk substrates with high dimensional accuracy, low residual stresses, and superb optical properties. In the present study, polycarbonate optical disk substrates were fabricated by injection compression molding and the birefringence, regarded as one of the most important optical properties for optical disk, is measured. The effects of various processing conditions upon the development of birefringence distribution were examined experimentally. It was found that the values of the birefringence distribution were very sensitive to the mold wall temperature history and the variance of the birefringence distribution in the radial direction was affected by the level of the packing and the compression pressure.