• Journal of Satellite, Information and Communications
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• v.6 no.2
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• pp.97-101
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• 2011

Interplanetary space between Sun and Earth is area of flowing very fast solar wind which is contained X ray, flare, corona mass, etc. occurred Sun surface to Earth. This solar wind is affected directly to Earth magnetosphere and ionosphere so that this bring out broadcasting and communication interruptions, satellite operation obstacles and power gird defects and etc..Solar wind flow in interplanetary space is measured as solar wind speed, density and direction by measuring scintillation value to be produced during radio source is passed through solar wind. The wider effective collective areas and the more radio sources, accuracy of solar wind measuring is got higher. Function test was performed using 3 tiles which was manufactured as prototype. Restriction of quantity of tiles, test was performed to confirm whether measured beam pattern is complied with requirement or not. In this paper, it is shown design and their specification of ground interplanetary radio measurement system as well as technical issues and resolutions which were raised during design phase. Also result of function verification test using prototype is suggested. It is confirmed that measured beam pattern was met with requirement.

• Clinical and Experimental Reproductive Medicine
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• v.34 no.3
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• pp.189-196
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• 2007

Objectives: The purpose of this study is to investigate the clinical significance of age and basal serum FSH in predicting the outcomes of in vitro fertilization (IVF) in patients with poor-ovarian response. Methods: From January 2000 to December 2004, 85 second IVF cycles of 85 poor-ovarian response patients under the age of 42 with a back-ground of the first IVF cycles at our infertility center and 5 or less oocytes were retrieved and their basal serum FSH levels of 15$\sim$25 mIU/ml were enrolled in this study. Exclusion criteria were patients with a male factor for the etiology of infertility and undergoing genetic diagnosis of embryo such as PGD. Flare-up protocol was used for ovarian stimulation in all cases. Results: When we stratified the study groups by patient's age, the younger age group (age<35, n=35) showed significantly higher implantation rate (19.0% versus 4.0%, p<0.05) and higher ongoing pregnancy rate (100% versus 14.3%, p<0.05) than the older age group (age$\geq$35, n=50). And then, when we stratified the study populations by basal serum FSH level, the lower FSH group (basal serum FSH<20 mIU/ml, n=58) showed significantly higher number of retrieved oocytes (4.6$\pm$0.7 versus 2.2$\pm$0.5, p<0.05) and lower cancellation rate (19.0% versus 55.6%, p<0.05) than higher FSH group (basal serum FSH$\geq$20 mIU/ml, n=27). Conclusions: In conclusion, it was suggested that the patient's age could predict the IVF outcomes in respect to its potency of pregnancy and ongoing pregnancy. Serum basal FSH levels could predict more accurately the ovarian response of cycle, but not clinical outcomes.

• Journal of Astronomy and Space Sciences
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• v.21 no.4
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• pp.329-342
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• 2004

In this paper, we present preliminary feasibility studies on three types of solar observation payloads for future Korean Science and Technology Satellite (STSAT) programs. The three candidates are (1) an UV imaging telescope, (2) an UV spectrograph, and (3) an X-ray spectrometer. In the case of UV imaging telescope, the most important constraint seems to be the control stability of a satellite in order to obtain a reasonably good spatial resolution. Considering that the current pointing stability estimated from the data of the Far ultraviolet Imaging Spectrograph (FIMS) onboard the Korean STSAT-1, is around 1 arc minutes/sec, we think that it is hard to obtain a spatial resolution sufficient for scientific research by such an UV Imaging Telescope. For solar imaging missions, we realize that an image stabilization system, which is composed of a small guide telescope with limb sensor and a servo controller of secondary mirror, is quite essential for a very good pointing stability of about 0.1 arcsec. An UV spectrograph covering the solar full disk seems to be a good choice in that there is no risk due to poor pointing stability as well as that it can provide us with valuable UV spectral irradiance data valuable for studying their effects on the Earth's atmosphere and satellites. The heritage of the FIMS can be a great advantage of developing the UV spectrograph. Its main disadvantage is that two major missions are in operation or scheduled. Our preliminary investigations show that an X-ray spectrometer for the full disk Sun seems to be the best choice among the three candidates. The reasons are : (1) high temporal and spectral X-ray data are very essential for studying the acceleration process of energetic particles associated with solar flares, (2) we have a good heritage of X-ray detectors including a rocket-borne X-ray detector, (3) in the case of developing countries such as India and Czech, solar X-ray spectrometers were selected as their early stage satellite missions due to their poor pointing stabilities, and (4) there is no planned major mission after currently operating Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI) mission. Finally, we present a preliminary design of a solar X-ray spectrometer covering soft X-ray (2 keV) to gamma ray (10 MeV).

• Clean Technology
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• v.27 no.1
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• pp.17-23
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• 2021

Black polymer spacers are currently used for physically separating aligned camera lenses in camera modules of mobile phones. However, the mechanical properties of polymer spacers have their limits, especially in the current trend of using more lenses in thinner camera modules. Thus, copper (Cu) becomes a good candidate for those polymer spacers because of its superior mechanical properties and its inherent blackness due to its black surfaced oxides, such as copper (II) oxide (cupric oxide, CuO). The latter property is critical in quality control because the closer the color of a spacer is to black, the less light interference and flaring phenomena can occur. A standard Cu blackening process and its operational conditions were proposed in this study through a comprehensive analysis of previous research and patents. The Cu blackening process is composed of cleaning, deoxidizing, activating, blackening and sealing. The effects of operational parameters, such as the temperature of each unit process and the activator concentration, were then investigated by measuring the blackness of the Cu strips with a colorimeter. The proposed operational conditions were determined by whether the blackness of Cu strips was within the on-spec. value used in the field.