• The Journal of Korean Academy of Prosthodontics
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• v.44 no.5
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• pp.606-616
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• 2006

Purpose: This experiment examined the effect of different surface treatment on the osseointegration and stability of implants. Material and methods: In this study, 40 each of machined, SLA and RBM implants, which are the most commonly used implants, were implanted into the tibia of 20 normal rabbits using $OsseoCare^{TM}$. The rabbits were sacrificed after 1 week, 4 weeks, 8 weeks and 12 weeks for implant stability analysis, removal torque analysis, histologic and histomorphometric analysis. Result : ISQ showed significant difference between Machined and RBM at first week and at 4 weeks. There was significant difference between Machined and both SLA and RBM(p<0.05) but after 8 weeks there were no significant difference between each group. In the removal torque, RBM showd significantly higher values than SLA and Machined surface at 1st week. At 4th and 12th week, there was significant difference between Machined and SLA, RBM(p<0.05). In the bone to implant contact variable, there was no significant difference between each surface treatment method. In the Machined surface group, there was no significant difference between each time interval. but in SLA group, there were significant differences between the 1st week and 12th week and in RBM group, there were significant differences between the 1st week and 8th, 12th week and between 4th and 12th week(p<0.05). The bone area showed significantly higher values in SLA and RBM compared to Machined surface 1st and 8th week and significantly higher values in SLA than Machined surface at the 4th week(p<0.05). Conclusion: The roughened surface of implants showed positive effect in the early stages of implantation and assisted in bone formation After the bone formation stage, there was no statistical difference between Machined and roughened surface groups. In dental implantation, where initial stability is critical to the success of implants, the use of roughened surface implants should assist in reducing the healing period after implantation.

• Journal of the korean academy of Pediatric Dentistry
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• v.47 no.3
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• pp.266-276
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• 2020

The purpose of this study was to compare the remineralization effect of 38% silver diamine fluoride (SDF) and 5% sodium fluoride (NaF) varnish on artificially induced enamel caries. The present study standardized the physiochemical characteristics of the tooth structure using bovine teeth, realized the wash-off action of agents using a saliva, reproduced an environment similar to mouth through pH-cycling, and comparatively assessed the remineralization effect of 38% SDF and 5% NaF varnish in a non-destructive method using micro-CT. And the remineralized enamel surface structure was analyzed by scanning electron microscopy (SEM) and energy dispersive X-Ray spectroscopy (EDS). In both SDF and NaF varnish, mineral density (△Hounsfield unit value) and the volume of enamel restored to normal mineral density through remineralization gradually increased with time. And the SDF showed a much higher level of increase in mineral density at all depths and remineralized volume than NaF varnish. According to SEM analysis, the surface roughness decreased in the order of artificial saliva, NaF varnish and SDF. In addition, EDS analysis showed that silver ion was precipitated on the enamel surface in SDF group. In conclusion, SDF had a greater remineralization effect than NaF varnish on demineralized enamel.

• Journal of Radiation Protection and Research
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• v.13 no.1
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• pp.8-20
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• 1988

The annual individual and collective doses to the thyroids of four age-dependent groups due to the in-take of I-131 released from the Younggwang nuclear power plant NU-1 & 2, Korea, are estimated using the model presented in ICRP 29. Sensitivity and robustness of the model are analyzed. In case of 0.12% fuel defect during normal operation, the collective dose is founded to be 3.05${\times}10^{-3}$man-thyroid-Sv, which is higher than the value calculated by the GASPAR code, 2.3${\times}10^{-3}$man-thyroid-Sv. The maximal individual annual doses resulting from an acute release are higher than those calculated under the assumption of continuous release by $1.4{\sim}1.7$ times. The most important pathway to the infant is milk and, in contrast, that to child, teen and adult is ingestion of crops. The model used is the calculation appears to be influenced by the variables such as roubstness-index. The weighted committed dose equivalent obtained by the ICRP 29 model is slightly higher than that calculated by the three-compartment model.

• Journal of Broadcast Engineering
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• v.20 no.6
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• pp.901-911
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• 2015

Many studies tried to develop a 3D display based stereo test as a substitute for the conventional stereo test. Although many 3D monitor based stereo tests have various advantages over the conventional stereo tests with printed stimuli, they have a crucial limitation in manipulating disparity. The least value for disparity manipulation is one pixel, which is too big to screen the normal stereo acuity in pc environment with a short viewing distance. In this explorative study, a Gabor image was employed as a test stimulus, because its position can be manipulated by changing its phase information, which allows sub-pixel manipulation for disparity. Instead of employing the methods of the conventional stereo tests where measurement was made only once for each of a wide range of disparity values, 10 replications were administrated for each of 6 disparity levels. The results from the test using Gabor images were compared with those using random dot stimulus because the latter stimulus was exactly the same as that of the conventional stereo test. The correlation coefficient between two tests was found to be moderate. After one month later, the whole test was repeated in the same settings. The correlation coefficient between test and retest results from Gabor images was found to be as high as that from a random dot stimulus, implying high test-retest reliability. These results suggest that a Gabor stimulus could be used as a test stimulus for the valid and reliable stereo test, even in the limited condition, such as 3D environment with a short viewing distance and a condition for evaluating the stereo acuity very precisely.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.5 no.1
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• pp.43-53
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• 1985

This study proposes a reliability based design criteria for the steel bridge (H-beam, plate-girder and composite-beam), which is most common type of steel bridge, and also proposes the theoretical bases of nominal safety factors as well as load and rasistance factors based on the reliability theory. Major 2nd moment reliability analysis and design theories including both Cornell's MFOSM (Mean First Order 2nd Moment) Methods and Lind-Hasofer's AFOSM(Advanced First Order 2nd Moment) Methods are summarized and compared, and it has been found that Lind-Hasofer's approximate and an approximate Log-normal type reliability formula are well suited for the proposed reliability study. A target reliability index (${\beta}_0=3.5$) is selected as an optimal value considering our practice based on the calibration with the safety pravisions of the current steel bridge design code. Galambo's theory is used for the derivation of the algorithm for the evaluation of uncertainties associated with resistences by LRFD Format and SGST Format, whereas the magnitude of the uncertainties associated with load effects are chosen primarily by considering our level of practice. It may be concluded that the proposed LRFD reliability based design provisions for the steel highway bridge give more rational design than the current standard code for steel highway bridge.

• The Journal of the Korea Contents Association
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• v.12 no.12
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• pp.335-344
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• 2012

Osteoporosis is increasing in Korea as it becomes an aging society with the rapid economic growth and the development of medical technology. Osteoporosis also develops due to chemo and radiation therapy of cancer which also increases owing to Westernized diet. Osteoporosis is caused by reduced bone density, has close relationship with the change of geometry of proximal femur, which is a factor of hip fracture risk. The purpose of this study was the analysis of the correlations of osteoporosis and the change of geometry of proximal femur, which was observed according to T-score variance. The 350 male and female patients are chosen from D hospital in Busan, who were classified by age, sex and T-score values (normal, osteopenia, and osteo porosis). The results show that the age and gender have significant difference in the incidence of osteoporosis; the disease classification according to T-score value has significant difference in the geometry of the proximal femur such as Cortical ratio calcar, Cortical ratio shaft, Hip/shaft Angle, Strength index, Section modulus, CSMI, and CSA, and is highly correlated with the incidence of osteoporosis. Therefore, the findings of this research is that the change of the geometry of the proximal femur could be used as an indicator in the diagnosis of osteoporosis, could enhance the accuracy of the diagnosis in the future, and could be used as a clinical predictive factors through the analysis of the correlations of T-score variance and the geometry changes of the proximal femur.

• Journal of Korean Ophthalmic Optics Society
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• v.21 no.3
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• pp.243-251
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• 2016

Purpose: This study evaluates the effectiveness of intermittent exotropia vision training through follow up of average 3 years using proprioceptive test (Maindot test). Methods: 35 people (18 men, 17 women) with mean age of 13.48 (${\pm}2.45$) with corrected visual acuity of 0.9 or higher and normal binocular vision and control were observed for changes between before, after, and 3 years following the vision training during the period from 2005 to 2009. Results: After training, the correlation between the changed amount of deviation and PRC(diplopia) value and symptoms was not significant (p>0.05). However, it showed a statistically significant (p<0.001) correlation that change of the binocular proprioceptive sense abilities is decreased subjective symptoms. Conclusions: Binocular proprioceptive sense may be used in variety of purposes and applications such as predictive evaluation of binocular symptoms, binocular function performance evaluation after vision training and prism treatment.

• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.308-319
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• 2016

In order to set the outdoor weather conditions to be applied to the design standard of the greenhouse heating and cooling system, outdoor air temperature and heating degree-hour for heating design, dry bulb temperature, wet bulb temperature and solar irradiance for cooling design were analyzed and presented. For every region in Korea, we used thirty years from 1981 to 2010 hourly weather data for analysis, which is the current standard of climatological normal provided by KMA. Since the use of standard weather data is limited, design weather conditions were obtained using the entire weather data for 30 years, and the average value of the entire data period was presented as a design standard. The design weather data with exceedance probability of 1, 2.5, and 5% were analyzed by the TAC method, and we presented the distribution map with exceedance probability of 1% for heating and 2.5% for cooling which are recommended by design standards. The changes of maximum heating load, seasonal heating load and maximum cooling load were examined by regions, exceedance probabilities, and setpoint temperatures. The proposed outdoor design conditions can be used not only directly for the greenhouse heating and cooling design, but also for the reinforcement of heating and cooling facilities and the establishment of energy saving measures. Recently, due to the climate change, sweltering heat in summer and abnormal temperature in winter are occurring frequently, so we need to analyze weather data periodically and revise the design standard at least every 10 years cycle.

• The Korean Society of Law and Medicine
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• v.12 no.2
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• pp.219-263
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• 2011

"Wrongful conception" is a medical malpractice claim in which the plaintiff is the parent of a normal, healthy infant whose conception was unplanned and unwanted. Medical malpractice in wrongful conception can be the result of a failure to provide informed consent to a patient, failure to properly perform a surgery, or a physician's negligent handling of a patient's problems. In the concrete, wrongful conception cases fall into two categories; those involving pre-conception negligence, such as a failed contraceptive, sterilization or failing of the controlling of embryo-number on the IVF, and those involving post-conception negligence, such as a failure to diagnose a pregnancy or to perform an abortion procedure. In addition, Medical malpractice can be the result of a failure to provide informed consent to a patient. When bad results occur by medical malpractice or failure to provide informed consent to a patient, the range of recovery of damages is decided by a traditional civil liability law. However the calculation of damages for wrongful conception is not easy because the high value of life is included in that case. So many courts opinions in foreign country and Seoul High Court decision in 1996 allow damages for the pregnancy, birthing process and sterilization costs, but refuses to allow damages for child rearing expenses. As to the range of recovery of damages for wrongful conception, one approach says that to allow damages in a suit such as this would mean that the physician would have to pay for the fun, joy and affection which plaintiff will have in the rearing and educating of the plaintiff's baby. To allow such damages would be against the dignity of the baby based on article 10 of the Constitution. However another approach says that damages are recoverable for all expenses related to child birth as well as for child rearing costs. Because the damages that the parents should bear a burden to the tort damage done is not a baby itself but child rearing costs. In other words, although the baby is healthy or not, economic burden of the parents can not be disregard. And denial of compensation for costs of child rearing may invalidate the role of liability law, grant the physician with a exemption certificate of liability. As a result, the medical field of procreation can be easily isolated from a liability of reparation. Therefore, on the liability law like the other medical malpractice action, parents who became pregnant or gave a birth by physician, wrongfully performed sterilization operation, etc. should be compensated for all damages relevant to unplanned and unwanted conception or birth as well as costs of child rearing.

• Journal of Oriental Neuropsychiatry
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• v.17 no.2
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• pp.61-73
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• 2006

Objective : This study was to investigate the effects of Banhabaekchulchunma-Tang(BCT) on Dementia induced by focal ischemic injury in the rats. Method : Experimental groups were divided into 4 groups ; Normal group, Control group, BCT1 group and BCT2 group. Control group were no treated after focal brain ischemic injury. BCT1 group were administered BCT 0.3 ml/kg to focal brain ischemic injuried rats for 21 days, BCT2 group were administered BCT 1.2 ml/kg to focal brain ischemic injuried rats for 21 days. The present author observed the number of errors on the eight-arm radial maze task , the rate of correct choice on the eight-arm radial maze task, the values of density of Cresyl Violet-stained sections in the hippocampal CA1 and the values of density of Acetlycholin Esterase(AchE) stained nuclei in the hippocampal CA1. Result : 1. The number of errors in the eight-arm radial maze task was significantly decreased in BCT1 group on 1-6th days. And it was significantly decreased in BCT2 group on 1st, 2nd, 3rd and 6th day compared with control group. 2. The rate of correct choice on the eight-arm radial maze task was increased in BCT1 group and BCT2 group compared with control group, but the value was not significant. 3. The values of density of Cresyl Violet-stained sections in the hippocampal CA1 were significantly increased in BCT1 group and BCT2 group compared with control group. 4. The values of density of AchE stained nuclei in the hippocampal CA1 were significantly increased in BCT1 group compared with control group. Conclusion : The present author thought that Banhabaekchulchunma-Tang could be used to cure dementia derived by the phlegm retention of fluid.