• Journal of the Korean Geographical Society
• /
• v.30 no.1
• /
• pp.57-67
• /
• 1995

The study on the factorial ecology of the residential patterns is to provide one of the yardsticks for description and comparison of urban structures. Many Korean geographers have adopted this method to analyse the urban structure of Korean cities. According to these studies, one of the main factors in Korean cities in large and middle sizes is family status. The spatial pattern of family status is zonal, similar to the cases of Japanese and Western cities. The age is one of the principal indices of familyf status, hence the author chose the age composition to analyse the residential patten. This Paper is to describe the residential segreagation pattern due to age composition and recent pattern changes in the Cheongju city, and than to explain the reason for these changes. All data are derived from the Population Censuses of Korea for 1970, 1980 and 1990. Eighteen groups of age with five-year interval (0-4, 5-9, 10-14, 15-19, 20-24, 25-29, 30-34, 35-39, 40-44, 45-49, 50-54, 55-59, 60-64, 65-69, 70-74, 75-79, 80-84, 85- and- over) are adopted here. Unit area for this analysis is administrative district(Dong) within Cheonaju city. District are classified into smaller groups based on the similarity of age composition, using the method of cluster analysis. The main findings are summarized as follows: 1. Population have increased remarkably in the eastern reaion neighboring CBD of Cheongju city in 1970's. And in western region from CBD new residential area have developed in 1980's. 2. Spatial pattarns showed a concentric circle type in central district and its neighbor regions and a sector type in periphery regions in 1970; a cirele type in central district and a sector typesin neighbor regions and periphery regions in 1980 and 1990. Thess residential pattern play an important role in the population composition ratio of younger aged group (l5-34) and older aged group (65-and-over). 3. Spatial change of types by age composition showed the higher ratio of groups of 0-9 and 35-49, and lower ratio of group 20-24 in 1970's. Dominent groups are ratio of 0-14, 40-49, 55-64, 7O-79, and 85- and- over in 1980's. These changes mainly appeared in central district and periphery regions. 4. The reasons for the change of age composition was the development of msnufacturing industries with the increase of population and new construction of residential areas both in the neighbor regions of cnetral district and periphery regions. These phenomena were caused by immigration of younger aged groups and increasing of residents of aged groups in these regions.

• Progress in Medical Physics
• /
• v.23 no.4
• /
• pp.317-325
• /
• 2012

The Varian PORTALVISION (Varian Medical Systems, US) shows significant overresponses as the off-center distance increases compared to the predicted dose. In order to correct the dose discrepancy, the off-axis correction is applied to VARIAN iX linear accelerators. The portal dose for $38{\times}28cm^2$ open field is acquired for 6 MV, 15 MV photon beams and also are predicted by PDIP algorithm under the same condition of the portal dose acquisition. The off-axis correction is applied by modifying the $40{\times}40cm^2$ diagonal beam profile data which is used for the beam profile calibration. The ratios between predicted dose and measured dose is modeled as a function of off-axis distance with the $4^{th}$ polynomial and is applied to the $40{\times}40cm^2$ diagonal beam profile data as the weight to correct measured dose by EPID detector. The discrepancy between measured dose and predicted dose is reduced from $4.17{\pm}2.76$ CU to $0.18{\pm}0.8$ CU for 6 MV photon beam and from $3.23{\pm}2.59$ CU to $0.04{\pm}0.85$ CU for 15 MV photon beam. The passing rate of gamma analysis for the pyramid fluence patten with the 4%, 4 mm criteria is improved from 98.7% to 99.1% for 6 MV photon beam, from 99.8% to 99.9% for 15 MV photon beam. IMRT QA is also performed for randomly selected Head and Neck and Prostate IMRT plans after applying the off-axis correction. The gamma passing rare is improved by 3% on average, for Head and Neck cases: $94.7{\pm}3.2%$ to $98.2{\pm}1.4%$, for Prostate cases: $95.5{\pm}2.6%$, $98.4{\pm}1.8%$. The gamma analysis criteria is 3%, 3 mm with 10% threshold. It is considered that the off-axis correction might be an effective and easily adaptable means for correcting the discrepancy between measured dose and predicted dose for IMRT QA using EPID in clinic.

• Journal of Korean Ophthalmic Optics Society
• /
• v.11 no.3
• /
• pp.281-291
• /
• 2006

The aim of this study was performed the clinical test using Netspeg lens for good visual acuity on subjects with abnormal refraction status. The subjects of one hundreds adults (fifty males, fifty females, mean=21 years, range=19 to 24) were recorded. The subjects were researched the history including the systemic health, medication, genetics, allergy, systemic disease and ocular disease. The refraction test was recorded the monocular and binocular using objective method. Visual acuity was performed the binocular status using the Netspeg lens and CR-39. Stereopsis test was performed the titmus fly and TNO at near distance using Netspeg lens and CR-39. The P-VEP test was used the 16 pattern size(Bausch Lomb, production in USA) with three channels. Also Subjects viewed the p-vep stimulus with binocular vision through the corrected visual acuity using the Netspeg lens and CR-39. The contrast sensitivity test was performed the contrast sensitivity chart(pelli-Robertson, USA) at 1m distance using the Netspeg lens and CR-39. The ultrastructure of surface on the Netspeg lens and CR-39 was observed the SEM(JMS-5800, made in Japan). The results of this study was as follows: 1. In corrected visual acuity of abnormal refraction using the Netspeg lens and CR-39, the Netspeg lens wearer were acquired the good visual field and clear visual acuity comparative to CR-39 wearer in the subject vision test. however the comfort of visual acuity was similar results in the Netspeg lens and CR-39. Also the subjects of Netspeg lens wearer was good visual acuity more than CR-39 wearer and in the analysis of P-VEP, the amplitude of wave on Netspeg lens used appears to be better through the CR-39(p>0.5). Besides, on the contrast sensitivity, the Netspeg lens wearer was good results than CR-39. The value on stereopsis with TNO by Netspeg lens wearer was better than CR-39 in results. However, in the stereopsis test with Titmus, the Netspeg lens and CR-39 wearer was similar results. 2. The ultrastructure of Netspeg lens surface was the smooth and fine shape more than CR-39. Also, Netspeg lens have a fine line structure in ultrastructure. In conclusion, the results of this study conformed that the surface ultrastructure of Netspeg lens used is more specific pin hole design structure than CR-39. This study indicated that the vision of Netspeg lens used have a better than CR-39 in the corrected visual acuity for abnormal refraction eye. Therefore, In this paper, we suggested that the ultrastructure and line structure of Netspeg lens was related to good visual function. However the visual function of the aspheric Netspeg and ultra waterproof Netspeg lens was similar results.

• Korean Journal of Animal Reproduction
• /
• v.23 no.3
• /
• pp.191-203
• /
• 1999

The objectives of this study were to investigate 1) the effects of Selenium(Se), Vitamin E (Vit. E) or recombinant Bovine Somatotropin(rBST) administration on fresh and frozen/thawed semen characteristics and 2) the effect of taurine on frozen/thawed semen characteristics in Hanwoo sires Hanwoo sires were randomly assigned to five groups (1. control, 2. rBST, 0.09mg/kg body weight (BW), 3. Vito E 1,500IU/kg BW, 4. Se 0.l mg/kg BW, 5. Vit. E 1,500IU plus Se 0.1 mg/kg BW). The administration of Se, Vit. E and rBST for each experimental group were given 6 times at 15 days interval by intramuscular injection. The administration of Se, Vit. E or rBST in Hanwoo sires didn't affect semen volume and pH values, but sperm viability was significantly increased comparing to the control group. Also, frozen/thawed semen analysis showed that the sperm viability increased, but any other effects were not found in total sperm :lumber, motility and abnormality among treatments. The addition of taurine in semen freezing extender had a beneficial effects on frozen/thawecl semen characteristics in all groups. The administrations of rBST, Vit. E and Se did not affect the sperm capacitation and acrosome reaction, either the ratio of F pattern(uncapacitated and acrosome intact sperm) or AR pattern(capacitated and acrosome-reacted sperm), but the ratio of B patten(capacitated and acrosome intact sperm) of treatment groups was significantly higher than that of control group, These results indicated that the viability, motility and quality of semen in Hanwoo sires were slightly increased by the injection of rBST, Vit. E and Se, and the addition of taurine in semen freezing extender were also increased the semen characteristics after thawing.