• Korean Journal of Social Welfare
• /
• v.54
• /
• pp.295-319
• /
• 2003

The study starts from the critical thought on why most of female-headed single-parent families are under poverty regardless of their hard working. The study is to explore the lives of low-income single-parent families as working poor and to develop comprehensive policies for them out of poverty and other social vulnerability, using the concept of social exclusion which has been broadly introduced in the field of social science. Specifically, the study aims to analyse the process of social exclusion of low-income single-parent households, by comparing the differential lives in the economic, social, political aspects among male-headed dual-parent household, female-headed single-parent household, and poor female-headed lone-parent household who is under the public poverty line. The study was based on the secondary data analysis. A total of 3182 samples(the first 2508, the second 235, and the third 439) were included. Using SAS 6.12, frequency, chi-square, means, and ANOVA were utilized for the statistical analysis. Results show that single mothers, on the whole, are vulnerable population in terms of employment, housing stability and income. Also, low-income households of single mothers are more negatively affected by the IMF economic crisis and carry more pessimism on their future. In comparison with male-headed households, single mothers have fewer support from social insurance as well as family resources and higher burdens of additional caring need for the old, the disabled, and the chronically ill. These findings identify the reality in which female-headed households with dependent children are exposed to the overall social vulnerability and thus are easily trapped into the social disadvantaged. finally, the study suggests the development of comprehensive policies and counter-measurements for low-income female-headed families to be the primary member in our society.

• Journal of muscle and joint health
• /
• v.7 no.1
• /
• pp.89-101
• /
• 2000

This study was carried out to compare the bone mineral density and risk factors of osteoporosis between normal and rheumatoid arthritis in postmenopausal women. Sixty-eight postmenopausal patients with rheumatoid arthritis(RA) were compared with 124 postmenopausal normal women. Data were collected from october, 1998 to April, 1999 at Dong-a university hospital in Pusan. From all subjects, individual characteristics such as age, body weight, height, age of menarche, duration of menopause, gravity, parity, and breast feeding period and factors of life style such as milk consumption, exercise, alcohol intake, cigarette smoking, coffee consumption were identified as influencing factors of osteoporosis by questionnaire. From RA patients, health assessment score, Ritchie articular index, erythrocyte sedimentation rate, C-reactive protein and steroid dosage were measured by rheumatologist on measuring bone mineral density. Bone mineral density was measured at the Lumbar spine, femoral neck, femur Ward's triangle, and femur trochanter using dual x-ray absorptiometry. The data was analyzed by using a frequency, t-test, Chi-square, ANCOVA with SPSS PC program. The results could be summarized as follows : 1) There was a significant difference in age and breast feeding period between RA patients and normal women. 2) RA patients took less calcium in the past and practiced less regular exercise in past and present than normal women. 3) There was no difference in lumbar bone mineral density between RA patients and normal women. 4) There was a significant difference in femur Ward's triangle and femur trochanter between RA patients and normal women after adjustment for age and breast feeding period. 5) The prevalence of osteoporosis of all subjects was the highest in femur Ward's triangle. In summary, our findings suggest that the bone mineral densities of femur Ward's triangle and trochanter in postmenopausal women with RA is significantly lower than normal women. Also the exercise participation rate of postmenopausal women with RA is lower than normal women. For the further study, we recommend to develop exercise program that improve the bone mineral density in femur Ward's triangle and trochanter and to test the effect of that exercise program.

• The Journal of Korean Academy of Prosthodontics
• /
• v.35 no.4
• /
• pp.647-661
• /
• 1997

The resin modified glass ionomer cements(RMGICs) have been used for years since 1989. Recently it has been developed for luting of fixed restorations. To evaluate the bond strength and marginal leakage of RMGICs for luting usage, the 80 extracted human molars which had uniform area of exposed dentin were cemented with 3 types of RMGICs(Fuji Duet, Advance, Vitremer), a conventional Glass Ionomer Cement(GIC-Fuji I), and a resin cement (Panavia 21) to base metal alloy(Ni-Cr-Be). After thermocycling the specimens were immersed in basic fuschin dye for measuring marginal leakage. The shear bond strength was measured with Instron and the maximum dye penetration was measured to 0.1mm. The types of fractured patterns were determined with stereoscope(${\times}7.5$). The results are as follows. 1. The difference between 3 RMGICs and a conventional GIC in shear bond strength was not statistically significant. It seemed that RMGICs had lower shear bond strength than resin cement. (p<0.01) 2. The mean scores of marginal leakage had no significant difference between the resin cement and 3 RMGICs but it was much higher in conventional GIC than the RMGICs (p<0.05) 3. It was determined that the manufacturer and the methods of dentin pretreatment determined the pattern of fracture surfaces and the frequency of adhesive failure between teeth and 3 RMGICs standed as in following order - Vitremer, Advance, Fuji Duet. (p<0. 01) When the fracture pattern was analyzed, it could be said that the materials and the method of dentin pretreatment have much effect on bonding states. This means that the dentin bonding agents should be improved. But the limited products in this experiment can not evaluate the physical properties of the entire RMGICs. Therefore a further study which can evaluate various RMGICs should be in progress to develope better cements.

• The Journal of Korean Society of Virology
• /
• v.30 no.3
• /
• pp.171-178
• /
• 2000

Herpes simplex virus, Varicella zoster virus and Human herpes virus-6 caused central nervous system infections and latent infections but there is no data of the 3 viruses being tested from the same cerebrospinal fluid samples with aseptic meningitis or encephalitis in adults patients. These viruses produced similar neurologic symptoms but difficulties existed in differentiating of etiologic agents and therefore the viruses needed to be detected in the early state. Herpes simplex virus encephalitis (HSVE) in adults, if not treated promptly was fatal. If treated with antiviral drugs in the early phase of encephalitis, neurologic sequales decreased by 65%. Recently, a PCR method for detection of HSVE with CSF was developed. VZV primary and secondary infections caused neurologic symptoms of encephalitis or meningitis. The second frequency of adult encephalitis that caused VZV were reported. HHV-6 caused CNS latent infection that was studied with normal adults brains. But there is no data of HSV, VZV and HHV-6 for aseptic meningitis and encephalitis of Korean adults through etiologic study. We cultured CSFs on HEp-2 cells and simultaneously tested for HSV PCR, VZV nested PCR and HHV-6 PCR with 8 specific primers. The PCR results of CSF from meningitis Korean adults were 13/19 (68.4%) for HSV, 10/19 (52.6%) for VZV and 12/19 (63.2%) for HHV-67/19 (36.8%) cases were triple infected HSV PCR, VZV PCR and HHV-6 PCR positive; 3/19 (15.8%) cases were dual infected HSV PCR and HHV-6 PCR positive; 1119 (0.5%) cases was VZV PCR positive. Strong viral DNA amplification of CSF means a causative virus may be present in aseptic meningitis or encephalitis patients and may cause clinical neurologic symptoms. HSV and HHV-6 viruses detection rate were higher than VZV by PCR with CSFs.

• Journal of radiological science and technology
• /
• v.39 no.3
• /
• pp.429-434
• /
• 2016

This study was performed in order to identify the relation between bone nineral density and life styles of some of Korean colleage students. A total of 121 college students were assessed through bone mineral density test on femoral neck and lumbar spine using dual energy X-ray absorptiometry(DEXA). The survey about their lifestyles with a self-rating questionnaire, was conducted from September 2014 to November 2014. SPSS 18.0 Program was used for those research data analyses such as the frequency analysis, the cross analysis. The percentage of the osteoporisis, osteopenia and normal groups were 0.0%, 24.8% and 75.2%. BMI, Regular menstrual cycle, Walking and Regular exercise in adolescence were positively related with T-score. But Using time of electronic devices was negative related with T-score. It can be concluded that desirable life style in time of college students and adolescence is important for their bone health. The necessity of preparing guideline for preventing bone disease in old age connected with the school curriculum should be recognized to the public and educational authorities.

• Korean Journal of Optics and Photonics
• /
• v.16 no.3
• /
• pp.209-216
• /
• 2005

A new second generation advanced thermal imager, which can be used for battle tank sight has been developed by ADD. This system uses a $480\times6$ TDI HgCdTe detector, operating in the $7.7-10.3{\mu}m$ wavelength made by Sofradir. The IR optics has dual field of views such as $2.67\times2^{\circ}$ in NFOV and $10\times7.5^{\circ}$ in WFOV. And also, this optics is used for athermalization of the system. It is certain that our sensor can be used in wide temperature range without any degradation of the system performance. The scanning system to be able to display 470,000 pixels is developed so that the pixel number is greatly increased comparing with the first generation thermal imaging system. In order to correct non-uniformity of detector arrays, the two point correction method has been developed by using the thermo electric cooler. Additionally, to enhance the image of low contrast and improve the detection capability, we have proposed the new technique of histogram processing being suitable for the characteristics of contrast distribution of thermal imagery. Through these image processing techniques, we obtained the highest quality thermal image. The MRTD of the LWIR thermal sight shows good results below 0.05K at spatial frequency 2 cycles/mrad at the narrow field of view.

• International Journal of Oral Biology
• /
• v.31 no.4
• /
• pp.127-133
• /
• 2006

[ $H_2O_2$ ], a member of reactive oxygen species (ROS), is known to be involved in the mediation of physiological functions in a variety of cell types. However, little has been known about the physiological role of $H_2O_2$ in exocrine cells. Therefore, in the present study, the effect of $H_2O_2$ on cholecystokinin (CCK)-evoked $Ca^{2+}$ mobilization and amylase release was investigated in rat pancreatic acinar cells. Stimulation of the acinar cells with sulfated octapeptide form of CCK (CCK-8S) induced biphasic increase in amylase release. Addition of $30\;{\mu}M\;H_2O_2$ enhanced amylase release caused by 10 pM CCK-8S, but inhibited the amylase release induced by CCK-8S at concentrations higher than 100 pM. An ROS scavenger, $10\;{\mu}M$ Mn(III)tetrakis(4-benzoic acid)porphyrin chloride, increased amylase release caused by CCK-8S at concentrations higher than 100 pM, although lower concentrations of CCK-8S-induced amylase release was not affected. To examine whether the effect of $H_2O_2$ on CCK-8S-induced amylase release was exerted via modulation of intracellular $Ca^{2+}$ signaling, we measured the changes in intracellular $Ca^{2+}$ concentration $([Ca^{2+}]_i)$ in fura-2 loaded acinar cells. Although $30\;{\mu}M\;H_2O_2$ did not induce any increase in $[Ca^{2+}]_i$ by itself, it increased the frequency and amplitude of $[Ca^{2+}]_i$ oscillations caused by 10 pM CCK-8S. However, $30\;{\mu}M\;H_2O_2$ had little effect on 1 nM CCK-8S-induced increase in $[Ca^{2+}]_i$. ROS scavenger, 1 mM N-acetylcysteine, did not affect $[Ca^{2+}]_i$ changes induced by 10 pM or 1 nM CCK-8S. Therefore, it was concluded that $30\;{\mu}M\;H_2O_2$ enhanced low concentration of CCK-8S-induced amylase release probably by increasing $[Ca^{2+}]_i$ oscillations while it inhibited high concentration of CCK-8S-induced amylase release.

• Elastomers and Composites
• /
• v.39 no.1
• /
• pp.12-22
• /
• 2004

The plasma surface modification of natural rubber vulcanizate was carried out using chlorodifluoromethane in a radio-frequency (13.56 MHz) electrodeless bell type plasma reactor. The modification was qualitatively assessed by Fourier transform infrared spectroscopy. The frictional force of the plasma-treated surface was found to decrease with the time of plasma treatment. An increase in the surface polarity, as evidenced by the decrease in contact angle of a sessile drop of water and ethylene glycol on the natural rubber vulcanizate surface, was noted with the plasma modification. In the case of similar plasma treatment of glass surface, only a reduction in the polarity was observed. The use of geometric and harmonic mean methods was found to be useful to evaluate the London dispersive and specific components of surface free energy. Irrespective of the method used for evaluation, an increasing trend in the surface free energy was noted with increasing plasma treatment time. However, the harmonic mean method yielded comparatively higher values of surface free energy than the geometric mean method. The plasma surface modification was found to vary the frictional coefficient by influencing the interfacial, hysteresis and viscous components of friction in opposing dual manners.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.23 no.12
• /
• pp.1327-1336
• /
• 2012

In this paper, the dual-faced monopole antenna, which is arranged by numerous rectangular ring patches in sequence for the multi-bands is proposed. The ring type structure of the patch can be increased the bandwidth. Therefore the bandwidth and beam width are improved by using multiple arrayed patches. When the ring type patches are inserted serially, the resonance frequencies are occurred by the current flow from the first ring patch. It is possible because the gap between the patches is very narrow. In addition, if the patches are composed on the same plane as the feed-line, fabrication could be very difficult because the gap between the patches is extremely narrow. The thickness and permittivity of the antenna, moreover, are very important parameters because both sides of the substrate are used. We finally found the optimal thickness and permittivity to generate the coupling effect by simulation. All patches are consisted of 4-steps which the patch size was decreased 85 % by each step. In conclusion, the resonant frequency bands are 1.75~2.6 GHz(850 MHz), 3.24~3.46 GHz(220 MHz), 3.8~4.0 GHz(200 MHz), and 4.4~4.9 GHz(500 MHz).

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.25 no.10
• /
• pp.1040-1049
• /
• 2014

In this paper, a quad-band antenna for DCS1800, PCS1900, WCDMA, WLAN and Mobile WiMAX application is proposed. The proposed antenna is a printed monopole structure, and consists of two rectangular ring-shaped radiating patches on the front side and two different size of L-shaped slots on the back side(ground plane). Two rectangular ring radiation patches are respectively resonant at 2 GHz and 3.5 GHz bands, and additional resonance is occurred at 5.3 GHz by the coupling effect between two ring patches. In addition, the optimized matching characteristic is obtained by controlling the gaps. Also, by adding two L-slots on the ground plane, additional resonant frequency band of 5.6 GHz is occurred. Finally the measured bandwidths of the proposed antenna below -10 dB return loss are 1,200 MHz(1.6~2.8 GHz), 800 MHz(3.2~4.0 GHz), 300 MHz(5.14~5.44 GHz), and 690 MHz(5.56~6.25 GHz). The radiation patterns have the omni-directional characteristic, and the measured antenna average gains at resonant bands are 0.86~4.07 dBi.