• Tunnel and Underground Space
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• v.33 no.3
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• pp.109-125
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• 2023

Disposal repository for high-level radioactive waste secures its safety by means of engineered and natural barriers. The performance of these barriers should be tested and verified through various aspects in terms of short and/or long-term. KAERI has been conducting various in-situ demonstrations in KURT (KAERI Underground Research Tunnel). After completing previous experiment, a conceptual design of an improved in-situ experiment, i.e. K-COIN (KURT experiment of THMC COupled and INteraction), was established and detailed planning for the experiment is underway. Preliminary characterizations were conducted in KURT for siting a K-COIN test site. 15 boreholes with a depth of about 20 m were drilled in three research galleries in KURT and intact rock specimens were prepared for laboratory tests. Using the specimens, physical measurements, uniaxial compression, indirect tension, and triaxial compression tests were conducted. As a result, specific gravity, porosity, elastic wave velocities, uniaxial compressive strength, Young's modulus, Poisson's ratio, Brazilian tensile strength, cohesion, and internal friction angle were estimated. Statistical analyses revealed that there did not exist meaningful differences in intact rock properties according to the drilled sites and the depth. Judging from the uniaxial compressive strength, which is one of the most important properties, all the specimens were classified as very strong rock so that mechanical safety was secured in all the regions.

• Economic and Environmental Geology
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• v.51 no.2
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• pp.185-201
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• 2018

Nuclear power plants(NPP) are constructed and operated to ensure safety against natural disasters and man-made disasters in all processes including site selection, site survey, design, construction, and operation. This paper will introduce a series of efforts conducted in Korea Hydro and Nuclear Power Co. Ltd., to assure the safety of nuclear power plant against earthquakes and other natural hazards. In particular, the present status of the earthquake, fault, and slope safety monitoring system for nuclear power plants is introduced. A earthquake observatory network for the NPP sites has been built up for nuclear safety and providing adequate seismic design standards for NPP sites by monitoring seismicity in and around NPPs since 1999. The Eupcheon Fault Monitoring System, composed of a strainmeter, seismometer, creepmeter, Global Positioning System, and groundwater meter, was installed to assess the safety of the Wolsung Nuclear Power Plant against earthquakes by monitoring the short- and long-term behavioral characteristics of the Eupcheon fault. Through the analysis of measured data, it was verified that the Eupcheon fault is a relatively stable fault that is not affected by earthquakes occurring around the southeastern part of the Korean peninsula. In addition, it was confirmed that the fault monitoring system could be very useful for seismic safety analysis and earthquake prediction study on the fault. K-SLOPE System for systematic slope monitoring was successfully developed for monitoring of the slope at nuclear power plants. Several kinds of monitoring devices including an inclinometer, tiltmeter, tension-wire, and precipitation gauge were installed on the NPP slope. A macro deformation analysis using terrestrial LiDAR (Light Detection And Ranging) was performed for overall slope deformation evaluation.

• Journal of Korea Port Economic Association
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• v.32 no.4
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• pp.149-163
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• 2016

Seafarers are an essential resource in maritime industries, which provide navigation skills, vessel maneuvering skills and fishing skills in the fishery industry. They also work as a driving force in pilotage, port operation, vessel traffic service, and marine safety. Other areas in maritime services, which rely on seafarer include safety management of ships, supervisory activities, and maritime accident assessment. In these ways, Korean seafarers have contributed to the growth of Korean economy. However, there have been issues of high separation rate, shortage of supply, multi-nationality, multiplicity of culture caused by employment of foreign seafarers, and aging. The present paper finds that maritime officers and fishery officers demonstrate differences in the statistics of on-board job taking and separation: the separation rate of fishery officers is higher than that of maritime officers. The existing data and statistics by the Korea Seafarer's Welfare & Employment Center could be improved by changing its structure from time series to panel data. The Korea Seafarer's Welfare & Employment Center is the ideal institution for collecting the panel data, as it has already accumulated and published relevant statistics regarding seafarer. The basic design method of the panel data is to adopt and improve it by including the information on ratings of maritime and fishery industries, ranks in a ship, personal information, family life, and career goal. Panel data are useful in short- and long-term forecasts of supply of Korean seafarers; demand evaluation of education, training, and reeducation of the seafarers; demographical dynamic analysis on Korean seafarers; inducement policy of long-term on board job taking in harmony with man-power demands in marine industries such as pilotage service; implementation of job attractiveness policy on Korean seafarers; and employment stabilization of Korean seafarers.

• Environmental Mutagens and Carcinogens
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• v.22 no.3
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• pp.187-198
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• 2002

Chlorpyrifos is an organophosphate insecticide and one of the most commonly and widely used insecticide. However, a little known about the dermal risk of chlorpyrifos on human being. Therefore, this study was conducted for the dermal risk assessment after exposure to chlorpyrifos in Korean farmers. First, skin irritation by chlorpyrifos (10 mg/$\textrm{cm}^2$, 50 mg/$\textrm{cm}^2$, 100 mg/$\textrm{cm}^2$, 250 mg/$\textrm{cm}^2$ in acetone) was determined in rabbits for 5 days considering the usage of chlorpyrifos short term highly exposure. The index of skin irritation by chlorpyrifos was increased in each dose and length of exposure dependent manners. Next, using benchmark dose (BMD$_{5}$) approach, the dose-response relationship was assessed to calculate the reference dose (RfD). The value of RfD was 2.84 $\mu\textrm{g}$/kg/day from 142.16 $\mu\textrm{g}$/kg/day BMD5 value divided uncertainty factor 50. Finally, we assessed human dermal risk of chlorpyrifos with exposure level and RfD. Skin absorbed levels were assumed with several exposure scenarios encounting the circumstances of exposure that application method, protection equipment and cloth, exposure time and exposure frequency during chlorpyrifos spraying. By the comparison of skin absorbed dose with the reference dose, it was identified that risk values (risk index) to skin chlorpyrifos exposure were 0.958 from the point of above results and it was recommended that the occurrence of hazard effect (skin irritation toxicity) of chlorpyrifos would not be expected. Risk index was smaller than 1 in the case of spraying vehicle mounted application, 1hour exposure time and wearing protective cloth exposure. Whereas, risk index was above 1 in the case of hand-held application, 2hour exposure time and wearing common cloth. Comparing two kinds of application method, total risk index of the hand held application (1.67) was higher than vehicle mounted (0.27). Therefore, chlorpyrifos skin exposure was mainly affected by application equipment and applied form. The results of risk assessment on the human dermal toxicity of chlorpyrifos should be required to control in keeping safety rules, skin surface area available for contact, spraying time ,and spraying frequency.y.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.12
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• pp.6602-6609
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• 2013

This study is expected to provide background data for establishing mitigation measures for malodor and for comparing complex odor criteria. The impact of malodor at the afflicted locations was analyzed using Industrial Source Complex Short Term 3 (ISCST3) model, which was recommended by the EPA. The Odor Emission Rates (ODR) for piglets and hogs were predicted based on the average, minimum, and maximum emission rates as classification. The forecasting result of the complex odor modelling of pigsty showed that tolerance limit was exceeded at an adjacent administration building, but tolerance limit was not surpassed at an afflicted location which was within 185m from the pigsty. The ISCST3 modelling of the satisfactory ODR for tolerance limit was accomplished at the administration building. From the prediction of this modelling, maximum emission rates based on 1hr at administration building were 10.59~52.93, 19.05~31.76, and 10.59 $OU/m^3/s/m^2$ at emission rates of 50%, 30%, and 10%. This emission rate was slightly higher than the tolerance limit of 10.00 $OU/m^3/s/m^2$. However, it was inferred that the tolerance limit could be satisfied if the emission rate of 10% was controlled.

• Journal of Chest Surgery
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• v.51 no.4
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• pp.260-265
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• 2018

Background: A method of wound closure using knotless suture material in the chest tube site has been introduced at our center, and is now widely used as the primary method of closing chest tube wounds in video-assisted thoracic surgery (VATS) because it provides cosmetic benefits and causes less pain. Methods: We included 109 patients who underwent VATS pulmonary resection at Samsung Medical Center from October 1 to October 31, 2016. Eighty-five patients underwent VATS pulmonary resection with chest drain wound closure utilizing knotless suture material, and 24 patients underwent VATS pulmonary resection with chest drain wound closure by the conventional method. Complications related to the chest drain wound were compared between the 2 groups. Results: There were 2 cases of pneumothorax after chest tube removal in both groups (8.3% in the conventional group, 2.3% in the knotless suture group; p=0.172) and there was 1 case of wound discharge due to wound dehiscence in the knotless suture group (0% in the conventional group, 1.2% in the knotless suture group; p=0.453). There was no reported case of chest tube dislodgement in either group. The complication rates were non-significantly different between the 2 groups. Conclusion: The results for the complication rates of this new chest drain wound closure method suggest that this method is not inferior to the conventional method. Chest drain wound closure using knotless suture material is feasible based on the short-term results of the complication rate.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.5
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• pp.791-803
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• 2016

Recently, frequency of extreme rainfall events in South Korea has been substantially increased due to the enhanced climate variability. Korea is prone to flooding due to being surrounded by mountains, along with high rainfall intensity during a short period. In the past three decades, an increase in the frequency of heavy rainfall events has been observed due to enhanced climate variability and climate change. This study aimed to analyze extreme rainfalls informed by their frequency of occurrences using a long-term rainfall data. In this respect, we developed a Poisson-Generalized Pareto Distribution (Poisson-GPD) based rainfall frequency method which allows us to simultaneously explore changes in the amount and exceedance probability of the extreme rainfall events defined by different thresholds. Additionally, this study utilized a Bayesian approach to better estimate both parameters and their uncertainties. We also investigated the synoptic patterns associated with the extreme events considered in this study. The results showed that the Poisson-GPD based design rainfalls were rather larger than those of based on the Gumbel distribution. It seems that the Poisson-GPD model offers a more reasonable explanation in the context of flood safety issue, by explicitly considering the changes in the frequency. Also, this study confirmed that low and high pressure system in the East China Sea and the central North Pacific, respectively, plays crucial roles in the development of the extreme rainfall in South Korea.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.14 no.2
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• pp.157-173
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• 2003

The history of pediatric psychopharmacology is very short and the research on safety, efficacy and side effects is preliminary and long-term effect on growth and maturation is not well known yet. Clinical findings have shown that the responses to antidepressants, antipsychotics, CNS stimulants and steroids in children and adolescents might be different from adult populations. Based on these findings, this paper reviewed three issues, Firstly, in developmental pharmacokinetics. the author discussed the developmental factors affecting drug absorption, distribution, protein-binding, metabolism and excretion. Secondly, in developmental pharmacodynamics, developmental characteristics of dopamine, serotonin, norepinephrine receptors and their clinical implications were reviewed. Lastly, in pharamcogenetic part, the clinical utility of pharmacogenetics, pharmacokinetic aspects of pharmacogenetics, the pharmacodynamic aspects of pharmacogenetics, the association studies of dopamine-related alleles in neuropsychiatric disorders such as attention-deficit hyperactivity disorders or Tourette’s disorders, pharmacogenetic studies dopamine-related alleles and the pharmacogenetic studies of serotonin-related alleles. Based on these preliminary research, future pharmacogenetic applications in childhood and adolescent psychiatry were also discussed.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.10 no.1
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• pp.117-127
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• 2015

Objectives : Most of pains are important symptoms caused by cancer transpered to spine. Harpagophyti Radix Pharmacopuncture is highly effective in reducing fever, pain, inflammation but was never used to reduce pain from cancer transpered to spine. So I intended to use Harpagophyti Radix Pharmacopuncture to control pain. The purpose of this study is to evaluate the clinical application of Harpagophyti Radix Pharmacopuncture for Bone Metastasis of Breast Cancer and Spinal Stenosis. Methods : We examined patient with Bone Metastasis of Breast Cancer and Spinal Stenosis who admitted Jaseng Korean Medicine Hospital. The patient was treated by Korean Medicine treatment and Harpagophyti Radix Pharmacopuncture. This case was assessed by Numerical Rating Scale(NRS), Oswestry Low Back Pain Disability Index(ODI), Short-Form 36 Health Survey(SF-36), ROM(Range of Movement) and Special Test. Results : In this study, the patient's pain was controlled and NRS, ODI were decreased. I could identify the improvement in life quality from the positive change of SF-36 and also found out that treatment was successful from the improvement of ROM, Special test. Conclusions : Harpagophyti Radix Pharmacopuncture with Korean Medicine treatment for Bone Metastasis of Breast Cancer and Spinal Stenosis was proved to be useful to the pain relief and function recovery, but further research should take place for clear understanding of the exact amount of dosage and safety. Moreover it must be accompanied by long term follow up research.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.4
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• pp.237-245
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• 2011

As necessity of safety re-evaluation for spent fuel storage facility has emphasized after the Fukushima accident, accuracy improvement of heat load evaluation has become more important to acquire reliable thermal-hydraulic evaluation results. As groundwork, parametric and sensitivity analyses of various storage conditions for Kori Unit 4 spent fuel storage pool and spent fuel depletion parameters such as axial burnup effect, operation history, and specific heat are conducted using ORIGEN2 code. According to heat load evaluation and parametric sensitivity analyses, decay heat of last discharged fuel comprises maximum 80.42% of total heat load of storage facility and there is a negative correlation between effect of depletion parameters and cooling period. It is determined that specific heat is most influential parameter and operation history is secondly influential parameter. And decay heat of just discharged fuel is varied from 0.34 to 1.66 times of average value and decay heat of 1 year cooled fuel is varied from 0.55 to 1.37 times of average value in accordance with change of specific power. Namely depletion parameters can cause large variation in decay heat calculation of short-term cooled fuel. Therefore application of real operation data instead of user selection value is needed to improve evaluation accuracy. It is expected that these results could be used to improve accuracy of heat load assessment and evaluate uncertainty of calculated heat load.