• Tunnel and Underground Space
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• v.10 no.4
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• pp.553-558
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• 2000

Since 1977, KAERI has conducted the fundamental R&D on the permanent disposal of potential HLW repository in Korea. The first ten year project is divided into three short-term phase studies. The first phase study which shall be finished in March of 2000, has the prime target to develop the disposal concept of HLW. Throughout this study the preliminary and generic disposal repository system has been introduced. The potential repository is proposed to be emplaced into crystalline rocks which is the most common rock types in Korea. The proposed depth of the repository is between 300 to 700 meter. The numerical code, MASCOT-K was developed to asserts the long term safety of the proposed repository concept. Based on this conceptual design preliminary safely assessment was performed. Results show that for the given disposal system the potential radioactive release it well below the regulatory limit.

• Korean Journal of Community Nutrition
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• v.3 no.2
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• pp.167-173
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• 1998

This study was performed to assess the lead and cadmium status of children residing in urban factory area and to see if there is a difference of lead and cadmium status between the group with normal iron status. The mean lead concentration of male hair was 9.55ppm which is significantly higher than 6.61 ppm that of female. The mean lead concentration of male urine sample was 0.04ppm, 10.3ppm and $48.14\mu{g/L}$, which is higher than 0.08ppm, 6.08ppm and $20.69\mu{g/L}$ of normal group, respectively. In a suboptimal group the proportion of children whose urinary lead is higher than normal$(35\mu{g/L)$was 87.3%, whereas 2.5% for a normal group. The mean cadmium concentration of male hair was 2.58ppm, which is higher than 2.48ppm that of a female. The mean cadmium concentration of erythrocyte, hair and urine was 0.25ppm, 2.65ppm and $38.83\mu{g/L}$, which is higher than 0.20ppm, 2.40ppm and $19.78\mu{g/L}$ of the normal group, respectively. The proportion of children whose urinary cadmium level is higher than the low limit of risk of cadmium intoxication$(40\mu{g/L)}$ was 21.4%, whereas 0% for a mormal group. Urinary lead and cadmium level showed significantly negative correlation with the RBC count, hematocrit, hemoglobin and serum ferritin, whereas they had significantly positive correlation with FEP/Hb(p<0.01). There was no correlation between the IQ and the level of lead and cadmium.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.10 no.3
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• pp.171-188
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• 2012

A GoldSim template program for a safety assessment of a hybrid-typed repository system, called "A-KRS," in which two kinds of pyro-processed radioactive wastes, low-level metal wastes and ceramic high-level wastes that arise from the pyro-processing of PWR nuclear spent fuels are disposed of, has been developed. This program is ready both for a deterministic and probabilistic total system performance assessment which is able to evaluate nuclide release from the repository and farther transport into the geosphere and biosphere under various normal, disruptive natural and manmade events, and scenarios. The A-KRS has been deterministically assessed with 5 various normal and abnormal scenarios associated with nuclide release and transport in and around the repository. Dose exposure rates to the farming exposure group have been evaluated in accordance with all the scenarios and then compared among other.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.4
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• pp.50-56
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• 2010

Supervisory Control and Data Acquisition Systems (SCADAs) is real-time monitor and control systems. SCADA systems are used to monitor or control chemical and transportation processes, in municipal water supply systems, electric power generation, transmission and distribution, gas and oil pipelines, and other distributed processes. SCADA refers to a large-scale distributed system. The supervisory control system is placed on top of a real time control system to control external processes. Emerging security technologies and security devices are decreasing the vulnerability of the power system against cyber threats. Dealing with these threats and analyzing vulnerabilities is an important task for equipment such as RTU, IED and FEP. To reduce such risks, we develop such a SCADA testbed. This paper presents the development of a testbed designed to assess the vulnerabilities SCADA networks(including serial communication).

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.6
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• pp.75-87
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• 2009

It is difficult to support QoS service in existing MAC Protocols in Wireless Mesh Network environments. while DCF can not support QoS, EDCA is operated with prioritized channel access method but can not give full performance. This thesis proposes frame management method to support QoS in Multi-Media DCF(MMDCF) MAC Protocol working in wireless mesh network. MMDCF uses ACH phase in TDMA frame to perform selection and elimination. Prioritized phases's count m and Fair Elimination phases's count n determine contention level and make string probability to only one win the contention. Forced TDMA Frame release method can support QoS requirements. MMDCF results good performance and good channel efficiency to support QoS requirements better than EDCA in multimedia stream environments.

• Journal of the Korean Society of Physical Medicine
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• v.13 no.1
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• pp.73-80
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• 2018

PURPOSE: The purpose of this study was to investigate the immediate effects of inspiratory muscle training on diaphragm movement and pulmonary function in healthy women. METHODS: The subjects of the study were 27 young women between ages 19 and 22 years who had no history of orthopedic damage for the last 6 months. The 27 participants were randomly selected and spontaneously participated and consented to the purpose of the study. This study measured diaphragm movement and pulmonary function under two different conditions, before and after inspiratory muscle training. Ultrasonography is appropriate for measuring diaphragm movement, and Pony Fx is appropriate to measure pulmonary function such as forced vital capacity (FVC), forced expiratory volume in 1 second ($FEV_1$), $FEV_1/FVC$ ratio, and peak expiratory flow (PEF) before and after inspiratory muscle training. Paired t-test with a significant level of .05 was used for statistical analysis. RESULTS: As a result, diaphragm movement significantly increases 1.45cm from before inspiratory muscle training (p<.05). Also, FVC, $FEV_1$, and FEP significantly increase 11.25%, 6.96%, and 8.18%, respectively, from before inspiratory muscle training (p<.05). CONCLUSION: The diaphragm movement and pulmonary function of the healthy women in this study were in stantly affected by inspiratory muscle training. From these results, we need to confirm effects of inspiratory muscle training on clinical patients such as pulmonary disease.

• Journal of Veterinary Clinics
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• v.11 no.1
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• pp.347-358
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• 1994

This study was peformed to investigate the morbidity of nutritional secondary hyperparathyroidism(NSH) caused by imbalance of Ca and p, and related athletic disease in Cheju pony racehorse. The seventeen horses with clinical signs among 33 NSH affected, administered CaCO$_3$(34 g) and Vita-rinka1(120 g) respectively for 40 days. The results were asd follows; Morbidity of NSR was 33 among 47 horses, and it was caused by the deficiency of Ca in 32 horses. In a case, level of Ca was norm질 although P was high. There was no case of Ca deficiency with P excess. Among 33 NSH affected horses, 13 were subclinical and 20 were clinical types with severe lameness in 6 and transient lameness in 14. Although there was no difference in bone density between transient lameness and normal horses on radiography, among six horses wlth severe lameness two showed hyperplasia at periosteum, one had low density of phalanges and metacarpal bones, and thin cortex. and there with fracture at carpus, nivicular bone and proximal sesamoids. The levels of FECa and FEP were recovered after CaCO$_3$ administration in 2 horses among ten, and after Vita-rinkal in all of seven. The clinical signs were disappeared in slx horses among ten CaCO$_3$ treated, and in five among seven Vita-rinkal treated. There were no differences on radiography in bone density and thickness of cortex on 14 horses with transient lameness. Three horses with severe signs were recovered to normal bone density and thickness of cortex, and there was no significant difference between two groups. In summary, the morbidity of NSH in Cheju pony racehorses was relatively high because of deficiency of Ca. Constant admistration of Ca supplements is desirable to treat and prevent athletic disease development in Cheju racehorses.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.229-232
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• 2003

A waste container, one of the key compartments in a multi-barrier system for a potential high level radioactive waste (HLW) repository in Korea ensures the mechanical stability against the lithostatic pressure of a deep geologic strata and the swelling pressure of the bentonite buffer. Also, it prohibits potential release of radionuclides for a certain period of time. before it is corroded by impurities. Even though the materials of a waste container is carefully chosen and all manufacturing processes are under heavy quality assurance, there might be a slight chance of intial defects in a waste container. Also, during the deposition of a waste container in a repository, there might be a chance of an incident affecting the integrity of a waste container. In this study, the FEP's and the scenarios over radiological impact of a potential initial waste container defect was developed. Then the total system performance assessment on this initial waste container failure (ICF) scenario was carried out by the MASCOT-K, one of the probabilistic safety assessment tools KAERI has developed. Results show that for the data set studied in this paper, the annual individual dose by the ICF scenario well meets the KINS regulation.

• Progress in Medical Physics
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• v.17 no.1
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• pp.1-5
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• 2006

A parallel plate detector containing PTFE films in FEP film for relative dosimetry was designed to measure the response of detectors to S and 10 MV X-rays from a medical linear accelerator through different thicknesses of lead. The dielectric materials were 100 m thick. The set-up conditions for measurements with this detector were as follows: SSD=100 cm the test detector was at a depth of 5 cm and the reference chamber was at a depth of 10 cm from the phantom surface for 6 and 10 MV X-rays. Lead blocks were designed to cover the irradiated field. They were added to the tray to increase thickness sequentially. We found that the detector response decreased exponentially with the thickness of lead added. The linear attenuation coefficients of the test detector and reference chamber were 0.1414 and 0.541, respectively, for 6 MV X-rays and 0.1358 and 0.5279 for 10 MV X-rays. The test detector response was greater than that of the reference chamber. The response function was calculated from the measured values of the test detector and reference chamber using optimization. These optimized constants for the detector response function were independent of theenergy. As a result of optimizing the response function between detectors, the use of a relative dosimeter was validated, because the response of the test detector was 1% for 6 MV X-rays and 4% for 10 MV X-rays.

• Korean Chemical Engineering Research
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• v.59 no.1
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• pp.127-137
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• 2021

Air emission charge for nitrogen oxide as a precursor of fine dust has been introduced and implemented within the country from 2020. Therefore, the development of economical combustion technology for NOx reduction has got more needed urgently. This study investigated the air-staging effect as a way to reduce the NOx during combustion of domestic unused forest biomass, recently possible to secure REC (Renewable Energy Certification) as a substitute for overseas wood pellets in a 0.1 MWth circulating fluidized bed combustion test-rig. Operating conditions were comparison with and without air-staging, the supply position of tertiary air (6.4 m, 8.1 m, 9.4 m in the combustor) and variation of air-staging ratio (Primary air:Secondary air:Tertiary air=91%:9%:0%, 82%:9%:9%, 73%:9%:18%). NO and CO concentrations in flue gas, profiles of temperature and pressure at the height of the combustion, unburned carbon in sampled fly ash and combustion efficiency on operating conditions were evaluated. As notable results, NO concentration with air-staging application under tertiary air supply at 9.4 m in the combustor reduced 100.7 ppm compared to 148.8 ppm without air-staging while, CO concentration increased from 52.2 ppm without air-staging to 99.8 ppm with air-staging. However, among air-staging runs, when tertiary air supply amount at 6.4 m in the combustor increased by air-staging ratio (Primary air:Secondary air:Tertiary air=73%:9%:18%), NO and CO concentrations decreased the lowest 90.8 ppm and 66.1 ppm, respectively. Furthermore, combustion efficiency at this condition was improved to 99.3%, higher than that (98.3%) of run without air-staging.