• Nuclear Engineering and Technology
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• v.52 no.12
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• pp.2874-2879
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• 2020

Due to excess reactivity, fresh nuclear fuel often contains burnable poisons. This research looks at six different burnable poisons and their impacts on reactivity, material attractiveness, and waste management. An MCNP simulation of a PWR fuel pin was performed with a fuel burnup of 60 GWd/MTHM to determine when each burnable poison fuel type would decrease below a k_∞ of 1. For determining the plutonium material attractiveness in each burnable poison fuel type, the plutonium isotopic content of the used fuel was evaluated using Bathke's Figure of Merit formula. For the waste management analysis, the thermal output of each burnable poison fuel type was determined through ORIGEN decay simulations at 100 and 300 years after being discharged from the core. The performance of all six burnable poisons varied over the three criteria considered and no single burnable poison performed best in all three considerations.

• Nuclear Engineering and Technology
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• v.52 no.7
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• pp.1367-1379
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• 2020

The small modular sodium-cooled fast reactor (SMSFR) is an important component of Generation-IV reactors. The objective of this work is to improve the reactivity control in SMSFR by using innovative systems, including burnable poisons and optimized control rods. SMSFR with MOX fuel usually exhibits high burnup reactivity loss that leads to high excess reactivity and potential fuel melting in control rod withdrawal (CRW) accidents, which becomes an important constraint on the safety and economic efficiency of SMSFR. This work applies two types of burnable poisons in a SMSFR to reduce the excess reactivity. The first one homogenously loads minor actinides in the fuel. The second one combines absorber and moderators in specific assemblies. The influence of burnable poisons on the core characteristics is discussed and integrated into the analysis of CRW accidents. The results show that burnable poisons improve the safety performance of the core in a significant way. Burnable poisons also lessen the demand for the number, absorption ability, and insertion depth of control rods. Two optimized control rod designs with rare earth oxides (Eu₂O₃ and Gd₂O₃) and moderators are compared to the conventional design with natural boron carbide (B₄C). The optimized designs show improved neutronic and safety performance.

• YAKHAK HOEJI
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• v.54 no.5
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• pp.341-347
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• 2010

The majority of forensic autopsies in Korea are performed by the National Institute of Scientific Investigation (NISI), and the NISI has carried out about 4,000 cases annually. Total 4,578 autopsies were performed by NISI in 2009, among them 2,918 cases (64%) were carried out at main office of NISI in Seoul, which is in charge of Seoul, Incheon and Gyeonggi province. In this study we investigated pattern of drugs & poisons in autopsy cases for recent three years in Korea. Postmortem specimens (bloods, gastric contents, etc) from autopsy cases by main office of NISI during 2007~2009 were screened for drugs & poisons. Using laboratory information management system of NISI (iLIMS), the kinds of drugs & poisons and the frequency were investigated. As the results, 1,705 cases were negative to drugs & poisons, it occupied 58% of total 2,918 autopsy cases in 2009. During three years (2007~2009), the kinds of drugs & poisons detected in specimens were 206, 185 and 203, respectively, and top three drugs were atropine (anticholinergic), chlorpheniramine (antihistamine) and lidocaine (local anaesthetic/anti-arrythmic). These drugs were supposed to be used not so much for suicidal or homicidal purpose as for therapeutic purpose in hospital. Meanwhile cyanide showed the highest frequency of poisons during 2007~2009, and the frequency was 32 cases in 2009. In case of pesticides, poisoning by paraquat (herbicide, 17 cases) showed the highest frequency, and methomyl (insecticide, 9 cases) and glyphosate (herbicide, 7 cases) were followed. Finally we selected 62 drugs as target drugs for systematic toxicological analysis (STA) for Korea. Poisons such as pesticides, natural toxins, volatile compounds should be included for STA in further study.

• Journal of Haehwa Medicine
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• v.18 no.2
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• pp.131-140
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• 2009

The aim of this study is to find out benefits of symptom questionnaire for oriental medical treatments. We analyzed symptom questionnaire of Korean association of abdomen diagnosis and treatment. Conclusions are as below. 1. Appetite, taste and digestion have a deep connection with accumulation and muscular contracture, with which the method of reinforcement and reduction is decided. 2. Feces, urine and, sweat have a deep connection with accumulation and water, with which the method of diaphoresis, emesis and purgation is decided. 3. Thirst and chillness and fever have a deep connection with water poisons and feverish feeling, based on which the cold and heat is classified. 4. we can find out the lesions with departmentalized physical sections of the head and the face, the chest, the abdomen, the articulations, the limbs and the skin. 5. It is possible to select appropriate prescription and assess before & after treatment through the questionnaire.

• Journal of Haehwa Medicine
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• v.18 no.2
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• pp.119-129
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• 2009

The purpose of this study is to find out relationship between "Yakjing" and the textbook of herbology. Conclusions are as below. 1. The herbs of accumulation of poison(結毒) generally show cold nature and have a reducing effect, which resemble the method of treating accumulation and stagnation. 2. The herbs of muscular contracture(攣) show sweet taste and tonifying effect, fall on the spleen and the stomach and have acts of treating urgency, relieving pain and conciliating, which resemble the method of treating urgency(急)and pain from accumulation and stagnation. 3. The herbs of water poisons(水毒) are categorized as those of cold nature and dampness and we can find out that water poisons is related to cold nature. 4. The herbs of feverish feeling(煩) treat heat. 5. The herbs of cardiothoracic part have an effect of regulating Gi and treat the phlegm disease.

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.245.2-245.2
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• 2001

• Nuclear Engineering and Technology
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• v.20 no.1
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• pp.19-26
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• 1988

The low leakage leading pattern has features as the placement of some fresh fuel assemblies in the core interior to reduce the neutron fluence on the pressure vessel and to enhance the neutron economics. But as fresh fuel assemblies are loaded in the core interior, the local power tends to exceed safety limit due to the high reactivity of the fresh assemblies. Therefore, a large number of burnable poisons must be utilized in a low leakage scheme to suppress the high assembly power as well as the excess reactivity. In this study the effects of burnable poisons are treated as a perturbation on the power distribution, and the 'Power Sensitivity Coefficient' concept is adopted. An application study is performed for cycle 1 of the Korea Nuclear Unit-7 (KNU-7) to justify the usefulness of the reverse depletion method coupled with the above concept. To obtain the optimal burnable poision distribution at the given burnup step, the linear programming technique is adopted. The result shows maximum 4.5% error in the amount of burnable poisons between the calculated and the reference values. It is concluded that the design methodology which consists of the reverse depletion, the power sensitivity coefficient concept, and the linear programming technique can be used to find the optimal turnable poison distribution.

• YAKHAK HOEJI
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• v.57 no.4
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• pp.289-292
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• 2013

A total of 2,080 forensic autopsies in Seoul, Incheon and Gyeonggi province were performed by the National Forensic Service (NFS) in 2010. After analysing blood samples collected at autopsies by GC-MS and LC-MS/MS, the types and prevalence of drugs and poisons in blood were investigated using our laboratory information management system. Among 2,080 cases, 1,061 cases (51%) were positive for drugs and poisons. Surprisingly, antidepressants were identified in 137 cases which comprised 13% of the positive cases. Twelve different kinds of antidepressants were determined: Amitriptyline, fluoxetine, nortriptyline, trazodone, imipramine, mirtazapine, citalopram, venlafaxin, clomipramine, paroxetine, sertraline and bupropion. Amitriptyline was the most frequently detected antidepressant and was identified in 39 cases. Moreover, amitriptyline, fluoxetine, and nortriptyline were included in the list of the 20 most commonly encountered drugs or poisons in the analysis of blood collected at autopsies from 2007 to 2009, indicating the prevalence of their use. In this study, the 137 antidepressant-related deaths were classified by the mode of death to predict the prevalence of these drugs. As a result, those deaths were divided into four groups based on the cause and mode of death: 56 cases of suicide with fatal concentrations of antidepressant drugs in blood, 6 homicidal cases directly or indirectly related to antidepressants, 59 natural deaths with antidepressants detected in blood and 16 deaths caused by fire or other accidents with antidepressants detected in blood. Because incidents involving antidepressants have been increasing, especially in suicides or homicides, it is necessary for the health authorities and law enforcement administrations to cooperate and share the statistical data for curbing the abuse of antidepressants. This report is expected to provide the reference data related with antidepressants for the investigation of the deaths.

• Journal of The Korean Society of Clinical Toxicology
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• v.1 no.1
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• pp.1-5
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• 2003

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.1
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• pp.158-160
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• 1997

Food poisoning accident occurred on May, 1996 at Oepo, Geoje County, Kyeongnam Province, Korea, and two persons were died within a few hours after ingestion of the soup prepared with wild mussel, Mytilus edulis, harvested on the sea rock. Paralytic shellfish poisons (PSP) were elucidated as the responsible toxins for the food poisons accident because the wild mussels caught after three days at the near place from the accident contained high toxicity of PSP ranged $650\~1000MU/g$ of edible meat by mouse bioassay. Gonyautoxin-1+4 $(42.7\%)$ and C1+C2 $(40.0\%)$ were detected as the major toxins in the mussels by fluorometric HPLC method. Although, the poison extracted out with drip during freezing and thawing, and the toxicity gradually decreased by boiling for 20 minutes, over 30 MU/g of toxins remained in the soup and meat, which indicated that they could be able to make food poisoning.