• Journal of the Korean Chemical Society
• /
• v.30 no.6
• /
• pp.538-547
• /
• 1986

The 8 rare earth elements were determined in the monazite concentrates by X-ray fluorescence spectrometry. The spectral line overlapping interferences from the other elements were investigated and the correction methods of interferences were studied using line overlap coefficients. The coefficients were calculated from the ratios of the intensities measured at the diffracted angle (2${\theta}$) of the analytical lines of other elements to the intensity of pure rare earth oxide. The coefficients were used to correct the line overlaps by a regression analysis. The linearities of calibration curves from the corrected intensities were remarkably improved, and their standard deviations were decreased. The analytical results agreed with that of the inductively coupled plasma(ICP) spectrometry within an allowable error range.

• Research in Community and Public Health Nursing
• /
• v.16 no.4
• /
• pp.404-414
• /
• 2005

Objectives: The present study proposed to evaluate 1st-month and 3rd-month health status, depression, self-efficacy and medical expenses of a community-based health promotive self-management program for old Koreans. Method: Participants in the CDSMP were selected from elders in a community health center through convenient sampling. The program included a 3-hour session per week for 14 weeks. Outcomes of evaluation in the 1st month and the 3rd month included modified Self-rated Health Status Scale, Center for Epidemiologic Studies Short Depression Scale, Self-Efficacy for Managing Chronic Disease 6-item Scale, and 1-item Medical Expenses Scale. Results: Self-rate health scores increased significantly just after the intervention (16.22), in the 1st month (17.57) and in the 3rd month (19.04) (x2=32.06. p=.000); Depression scores (reversed) also increased significantly just after the intervention (6.04), in the 1st month (7.75) and in the 3rd month (8.39) ( $x^2=29.92$. p=.000); Self-efficacy score increased significantly just after intervention (12.87) but it decreased in the 1st month (12.73) and in the 3rd month (12.04). But all of the three scores were still higher than those before the intervention (8.65) ($x^2=32.42$. p=.000): Medical expense score decreased at the end of the intervention (1.57) but the cost score increased in the 1st month (2.48) and in the 3rd month (2.39) ($x^2$=7.81. p=.050). Conclusion: CDSMP is effective in increasing self-rate health and self-efficacy and in decreasing depression in the Korean elderly. However, no significant effect of the program was observed in decreasing the medical cost of the Korean elderly.

• Journal of the Korea Convergence Society
• /
• v.8 no.3
• /
• pp.191-197
• /
• 2017

This development is for non-destructive machine using X-Ray source about detecting outline faults of below middle size products. The differentiation is product of research and development unspecialized small and medium-sized products using X-Ray light sources can check real time if the surface of an external fault of radiation dose reference, within the leakage. The speed control is possible by software solution. In addition, we're working on possibly block doors for worker safety and equipment at the same time that inner drive can be identified in the image. These principles, as a key enabler of the current inspection system such as the container is small to medium-sized parts - a long way from utilization level is possible. This research will give rise to major effects for other various non-destructive market industries except car-industry. The most important fact is that this developed non-destructive machine is controlled below $0.2micro-S{\mu}v$.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.26 no.12
• /
• pp.1112-1115
• /
• 2015

Recently, there have been advancements in radar related material technology, circuit design techniques and architecture design techniques. These have led to developments in radars' performance while decreasing the costs. Many studies have been carried out to apply radars to multipurpose application. In this study, a reconfigurable S-/X- band radar structure for multipurpose application is proposed and implemented. This radar measures a $51.2cm{\times}50.6cm$ target for 10 times from 2 m to 6 m range with 0.25 m distance step. The measured results show that this radar has 26.40 cm maximum range error, 5.63 cm average range error, and 0.24 cm range error variance at S-band while it has 8.53 cm maximum range error, 2.52 cm average range error, and 0.04 cm range error variance at X-band.

• Journal of the Korean Ceramic Society
• /
• v.38 no.11
• /
• pp.1042-1045
• /
• 2001

Microwave dielectric properties of Ba(Zn$_{1}$3/Nb$_{2}$3/) $O_3$-Sr(Zn$_{1}$3/Nb$_{2}$3/) $O_3$(BZN-SZN) system were investigated as a function of sintering temperature and Zr $O_2$content. Density was increased and the temperature coefficient of resonant frequency (TCF, $\tau$$_{f}$) decreased with increasing sintering temperature. However dielectric constant (K) and Q$\times$f value did not change markedly with the sintering temperature. For the samples sintered at the same temperature, density, dielectric constant, and Q$\times$f value were increased and TCF was decreased with increasing Zr $O_2$concentration. Especially, the dielectric constant of the sample increased with x and exhibited the maximum value ($\varepsilon$$_{r}$=41) when x=0.6 at 1575$^{\circ}C$ sintered. TCF decreased with x and exhibited the minimum value ($\tau$$_{f}$=+0.8ppm/$^{\circ}C$) when x=1.0..0.

• Clinical and Experimental Reproductive Medicine
• /
• v.27 no.3
• /
• pp.275-282
• /
• 2000

Objective: This study was to determine the effect of different concentration of calcium III medium on the preimplantational development of zygotes and early 2 cell embryos. Methods: Female mice of ICR strain ($5{\sim}8$ weeks old) were superovulated and mated with fertile males. Zygotes or early 2-cell embryos were collected by flushing the oviducts $31{\sim}32$ hours after hCG injection. The embryos were cultured in various concentrations of $Ca^{2+}$ in medium or with EDTA, EGTA and $Ni^{2+}$. Result and Conclusion: Treatment of high concentraion of $Ca^{2+}$ (3.42 mM $(2X){\sim}17.l$ mM (10X)) in medium didn't develop well compared to the control. Low concentrations of $Ca^{2+}$ (0.214mM $(1/8X){\sim}0.855$ mM (1/2X) were deterimental to development beyond 2-cell stage. EDTA, $Ca^{2+}$ chelating agent was treated with ranged concentrations of EDTA (0.014 $mM{\sim}0.107$ mM) to medium contaning 1.71 mM $Ca^{2+}$ showed beneficial effect to development to blastocyst compared to the control. EGTA, extracellular $Ca^{2+}$ chelator, was treated with ranged concentrations of EGTA ($0.014{\sim}0.107$ mM) to the medium contaning 1.71 mM $Ca^{2+}$. There is no significant difference with the control. $Ni^{2+}$ (50 ${\mu}M$), T-type $Ca^{2+}$-channel blocker was treated to medium contaning low concentration of $Ca^{2+}$. It overcame 2-cell block significantly. Rate of degenerated embryos decreased and developmental rate to morula and blastocyst increased more than low $Ca^{2+}$ concentration alone. Further studies are needed for the overcoming effect of 2-cell block by $Ni^{2+}$.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2017.05a
• /
• pp.168-171
• /
• 2017

In this study, we observed degradation mechanism of FKM O-ring by X-ray photoelectron spectroscopy(XPS) at atmosphere condition. FKM O-ring had 3.53mm of cross-sectional diameter and 91.67mm of inner diameter. After thermal degradation, oxygen atom concentration of FKM O-ring was increased to 20.39%, and fluorine atom concentration was decreased to 8.29%. We observed that degradation reaction occurred by oxidation reaction. By C1s and F1s peak analysis, we confirmed that oxidation reaction usually occurred at C-F bonding of FKM main chain. Also, carboxyl group(C-OH, C=O, O=C-O) produced by oxidation reaction from O1s peak analysis.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2001.11a
• /
• pp.167-170
• /
• 2001

The stochiometric mix of evaporating materials for the CdGa$_2$Se$_4$ single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films, CdGa$_2$Se$_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperature were 630$^{\circ}C$ and 420$^{\circ}C$, respectively. The crystalline structure of single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of CdGa$_2$Se$_4$ single crystal thin films measured from Hall erect by van der Pauw method are 8.27x10$\^$17/ cm$\^$-3/, 345 $\textrm{cm}^2$/V$.$s at 293 K, respectively. From the Photocurrent spectrum by illumination of perpendicular light on the c-axis of the CuInSe$_2$ single crystal thin film, we have found that the values of spin orbit splitting ΔSo and the crystal field splitting ΔCr were 106.5 meV and 418.9 meV at 10 K, respectively. From the photoluminescence measurement on CdGa$_2$Se$_4$ single crystal thin film, we observed free excition (E$\_$X/) existing only high quality crystal and neutral bound exiciton (D$\^$0/,X) having very strong peak intensity. Then, the full-width-at-half-maximum(FWHM) and binding energy of neutral donor bound excision were 8 meV and 13.7 meV, respectivity. By Haynes rule, an activation energy of impurity was 137 meV,

• Journal of Embryo Transfer
• /
• v.30 no.3
• /
• pp.225-228
• /
• 2015

Understanding the behavior of transgenes introduced into oocyte or embryos is essential for evaluating the methodologies for transgenic animal production. To date, many studies have reported the production of transgenic pig embryos with, however, low efficiency in environment of blastocyst production. The aim of present study was to determine the expression and duration of transgene transferred by intracytoplasmic sperm injection-mediated gene transfer (ICSI-MGT). Embryos obtained from the ICSI-MGT procedure were analysed for the expression of GFP and then for the transmission of the transgene. Briefly, fresh spermatozoa were bound to exogenous DNA after treatment by Triton X-100 and Lipofectin. When ICSI-MGT was performed using sperm heads with tails removed, the yield of blastocyst (25.3%), treated with Lipofectin (18.8%) and Triton X-100 (19.2%) were observed. Treatments of Lipofectin or Triton X-100 did not further improve the rates of blastocysts. Moreover, the apoptosis rates of embryos were obtained from the control and LIpofectin groups (8.7%, 9.7%, respectively), but were significantly higher in the Triton X-100 group (13.0%). Our results demonstrated that ICSI-MGT caused minimal damage to oocytes that could develop to full term. Moreover, the embryos derived by ICSI-MGT have shown prolonged exogenous DNA expression during preimplantation stage in vivo. However, more efforts will be required to improve the procedures of both sperm treatments cause of high frequency of mosaicisms.

• Bulletin of the Korean Space Science Society
• /
• 2010.04a
• /
• pp.40.4-41
• /
• 2010

Using magnetic field and plasma moment data obtained by THEMIS satellites(A, D, and E), we selected 203 fast flow events accompanied by dipolarization in the near-Earth region( X(GSM) = -7 ~ -12 RE) and statistically examined their properties. It was found that most of the fast flows show the maximum velocity between 1 minute before dipolarization onset and 2 minutes after onset and proceed earthward and duskward. We also found that only the flows with low velocity of less than 400 km/s are observed at X > -8 RE, while the high velocity flows(as well as low velocity flows) are observed at the further tailward region(X < -8 RE). And most of the tailward flows are slow regardless of distance at X(GSM) = -7 ~ -12 RE. On the other hand, if we consider the fast flow as a bubble (Pontius and Wolf, 1990), the entropy parameter, PV5/3 is an important factor to describe the plasma sheet dynamics. Thus we investigated the relationship between the flow velocity and the amount of change in PV5/3 before and after dipolarization onset and found out that the dipolarizations with more depleted entropy parameter tend to show higher flow velocity. Also we examined how the magnetic field at geosynchronous orbit responds to the fast flow accompanied by dipolarization in the near-earth plasma sheet, using the measurements from GOES 11 and 12 statellites. We found that most of the fast flows do not reach geosynchronous orbit as suggested by Ohtani et al. (2006).