• Title/Summary/Keyword: High Burn-Up

Search Result 79, Processing Time 0.025 seconds

Analysis of High Radioactive Materials in Irradiated DUPIC SIMFUEL Using EPMA (EPMA를 이용한 DUPIC 사용후 핵연료 핵분열 생성물의 특성 분석)

  • 정양홍;유병옥;주용선;이종원;정인하;김명한
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.2 no.2
    • /
    • pp.125-133
    • /
    • 2004
  • Fission products of DUPIC (Direct Use of Spent PWR Fuel in CANDU Reactors) fuel, irradiated in HANARO research reactor with 61 ㎾/m of maximum linear power and 1,770 ㎿d/tU of average burn-up, was characterized by EPMA(Electron Probe Micro Analyzer). In order to find accurate characterization, the analysis results by EPMA of fresh simulated DUPIC fuel containing fission products as chemicals were compared with that of wet chemical analysis. The metallic precipitates observed at the center of the fresh simulated DUPIC fuel were about 1 $\mu\textrm{m}$ in size and their major components by EPMA were Mo-53.89 at.%, Ru-37.40 at.%, and Pd+Rh-8.71 at.%. Established procedure through the fresh simulated DUPIC fuel was applied to the irradiated DUPIC fuel. Observed size of metallic precipitates were 2∼2.5 $\mu\textrm{m}$ and their compositions were Mo-47.34 at.%, Ru-46 at.%, and Pd+Rh-6.65 at.%. What are uncommon things for this experiment, special treatment for improving the conductivity was attempted to the specimen and the conditions of exact irradiation of electron beam to small metallic precipitate were suggested.

  • PDF

TERRAPOWER, LLC TRAVELING WAVE REACTOR DEVELOPMENT PROGRAM OVERVIEW

  • Hejzlar, Pavel;Petroski, Robert;Cheatham, Jesse;Touran, Nick;Cohen, Michael;Truong, Bao;Latta, Ryan;Werner, Mark;Burke, Tom;Tandy, Jay;Garrett, Mike;Johnson, Brian;Ellis, Tyler;Mcwhirter, Jon;Odedra, Ash;Schweiger, Pat;Adkisson, Doug;Gilleland, John
    • Nuclear Engineering and Technology
    • /
    • v.45 no.6
    • /
    • pp.731-744
    • /
    • 2013
  • Energy security is a topic of high importance to many countries throughout the world. Countries with access to vast energy supplies enjoy all of the economic and political benefits that come with controlling a highly sought after commodity. Given the desire to diversify away from fossil fuels due to rising environmental and economic concerns, there are limited technology options available for baseload electricity generation. Further complicating this issue is the desire for energy sources to be sustainable and globally scalable in addition to being economic and environmentally benign. Nuclear energy in its current form meets many but not all of these attributes. In order to address these limitations, TerraPower, LLC has developed the Traveling Wave Reactor (TWR) which is a near-term deployable and truly sustainable energy solution that is globally scalable for the indefinite future. The fast neutron spectrum allows up to a ~30-fold gain in fuel utilization efficiency when compared to conventional light water reactors utilizing enriched fuel. When compared to other fast reactors, TWRs represent the lowest cost alternative to enjoy the energy security benefits of an advanced nuclear fuel cycle without the associated proliferation concerns of chemical reprocessing. On a country level, this represents a significant savings in the energy generation infrastructure for several reasons 1) no reprocessing plants need to be built, 2) a reduced number of enrichment plants need to be built, 3) reduced waste production results in a lower repository capacity requirement and reduced waste transportation costs and 4) less uranium ore needs to be mined or purchased since natural or depleted uranium can be used directly as fuel. With advanced technological development and added cost, TWRs are also capable of reusing both their own used fuel and used fuel from LWRs, thereby eliminating the need for enrichment in the longer term and reducing the overall societal waste burden. This paper describes the origins and current status of the TWR development program at TerraPower, LLC. Some of the areas covered include the key TWR design challenges and brief descriptions of TWR-Prototype (TWR-P) reactor. Selected information on the TWR-P core designs are also provided in the areas of neutronic, thermal hydraulic and fuel performance. The TWR-P plant design is also described in such areas as; system design descriptions, mechanical design, and safety performance.

An in-depth interview for use of moxibustion therapy in Korea (국내 뜸 요법 임상 실태 파악을 위한 면접조사)

  • Han, Chang-Hyun;Shin, Mi-Suk;Kang, Kyung-Won;Kang, Byoung-Kab;Park, Sun-Hee;Choi, Sun-Mi
    • Korean Journal of Acupuncture
    • /
    • v.25 no.1
    • /
    • pp.85-97
    • /
    • 2008
  • Objectives : Moxibustion therapy is one of the most popular oriental treatments in Korea. In this study, we operate the in-depth interview for use of moxibustion therapy in Korea. Methods : Survey questions were developed based on consensus of acupuncture professors. The list of the Korean medical doctors with experiences more than 10 years is provided by the Association of the Korean Oriental Medicine. The in-depth interview was conducted in 30 Korean medical doctors who answered in the previous telephone survey that they use moxibustion therapy for more than 30 % of patients everyday. Interview survey with them were conducted by the well-trained interviewers of Korea Institute of Oriental Medicine in medical researcher from 22th May to 28th June 2007. Results : Korean medical doctors prefer to use the moxibustion with moxa stick (83.9%). The most common treatment disease was musculo-skeletal disorder (28.9%), gynecology (14.1%), digestive disorder (28.6%). The most common treatment area was the abdomen (35.3%), back (22.5%), lower extremity (15.8%) and upper extremity (16.9%). Indirect moxibustion’s was as frequent as 73.5% of moxibustion method. The most common instrument for treating was mini-moxa of manufactured goods (39.3%). Most Korean medical doctors (48.8%) took up the position that bring symptom relief following good treatment area. 'High preferences of patients' (32.7%) was one of moxibustion strong points but 'Lots of smell and smoke' (54.7%)' was a weak points. The most common side effects was the 'slight burn' (34.9%), 'skin rash' (22.5%), 'skin pruritus' (23.8%) Conclusions : This survey provides unique insight into the perception of the Korea medical doctor at moxibustion therapy. Future research needs to provide more in-depth insight into doctor views of the experience.

  • PDF

EPMA Analysis of Inter-reaction Layer in Irradiated U3Si-Al Fuels (EPMA를 이용한 U3Si/Al 조사 핵연료의 반응층 분석)

  • Jung, Yang-Hong;Yoo, Byung-Ok;Kim, Hee-Moon;Park, Jong-Man;Kim, Myung-Han
    • Analytical Science and Technology
    • /
    • v.17 no.4
    • /
    • pp.355-362
    • /
    • 2004
  • Fission products and Inter reaction layer of $U_3Si-Al$ dispersion fuel, irradiated in HANARO research reactor with 121 kW/m of maximum liner power and 63 at% of average burn-up, was characterization by EPMA (Electron Probe Micro Analyzer). The fuel punching system developed by Irradiated Materials Examination Facility (IMEF) has used to make these samples for the EPMA. With this system a very small and thin specimen which is 1.57 mm in diameter and 2 mm in thickness respectively has been fabricated to protect the EPMA operator from high radioactive fuel and to mini-mize the equivalent dose rate less than 150 mSv/h. EPMA was performed to observe layers of sectional, Inter-reaction and oxide with specimens of cutting and polished. Stoichiometry in the Inter-reaction layer with $16{\mu}m$ of thickness was $U_{2.84}$ Si $Al_{14}$ with calibration of $UO_2$ and $U_{3.24}$ Si $Al_{14.1}$ with calibration of standard specimen. metallic precipitates in this layer were not observed using fission products examination.

A Guidance Methodology Using Ubiquitous Sensor Network Information in Large-Sized Underground Facilities in Fire (대형 지하시설물에서 화재발생 시 USN정보를 이용한 피난 유도 방안)

  • Seo, Yonghee;Lee, Changju;Jung, Jumlae;Shin, Seongil
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.28 no.4D
    • /
    • pp.459-467
    • /
    • 2008
  • Because of the insufficiency of ground space, the utilization of underground is getting more and more in these days. Moreover, underground space is being used not only buildings but multipurpose space for movement, storage and shopping. However, ground space has vital weakness for fire compared to ground space. Especially in case of underground shopping center, there are various stuffs to burn and poisonous gas can be exposed on this count when the space is burned. A large number of casualties can be also occurred from conflagration as underground space has closed structures that prevent rapid evacuation and access. Therefore, this research proposes the guidance methodology for evacuation from conflagration in large-sized underground facilities. In addition, suggested methodology uses high technology wireless sensor information from up-to-date ubiquitous sensor networks. Fire information collected by sensors is integrated with existing underground facilities information and this is sent to guidance systems by inducing process. In the end, this information is used for minimum time paths finding algorithm considering the passageway capacity and distance. Also, usefulness and inadequacies of proposed methodology is verified by a case study.

Optimal flammability and thermal buckling resistance of eco-friendly abaca fiber/ polypropylene/egg shell powder/halloysite nanotubes composites

  • Saeed Kamarian;Reza Barbaz-Isfahani;Thanh Mai Nguyen Tran;Jung-Il Song
    • Advances in nano research
    • /
    • v.16 no.2
    • /
    • pp.127-140
    • /
    • 2024
  • Upon direct/indirect exposure to flame or heat, composite structures may burn or thermally buckle. This issue becomes more important in the natural fiber-based composite structures with higher flammability and lower mechanical properties. The main goal of the present study was to obtain an optimal eco-friendly composite system with low flammability and high thermal buckling resistance. The studied composite consisted of polypropylene (PP) and short abaca fiber (AF) with eggshell powder (ESP) and halloysite clay nanotubes (HNTs) additives. An optimal base composite, consisting of 30 wt.% AF and 70 wt.% PP, abbreviated as OAP, was initially introduced based on burning rate (BR) and the Young's modulus determined by horizontal burning test (HBT) and tensile test, respectively. The effects of adding ESP to the base composite were then investigated with the same experimental tests. The results indicated that though the BR significantly decreased with the increase of ESP content up to 6 wt.%, it had a very destructive influence on the stiffness of the composite. To compensate for the damaging effect of ESP, small amount of HNT was used. The performance of OAP composite with 6 wt.% ESP and 3 wt.% HNT (OAPEH) was explored by conducting HBT, cone calorimeter test (CCT) and tensile test. The experimental results indicated a 9~23 % reduction in almost all flammability parameters such as heat release rate (HRR), total heat released (THR), maximum average rate of heat emission (MARHE), total smoke released (TSR), total smoke production (TSP), and mass loss (ML) during combustion. Furthermore, the combination of 6 wt.% ESP and 3 wt.% HNT reduced the stiffness of OAP to an insignificant amount by maximum 3%. Moreover, the char residue analysis revealed the distinct differences in the formation of char between AF/PP and AF/PP/ESP/HNT composites. Afterward, dilatometry test was carried out to examine the coefficient of thermal expansion (CTE) of OAP and OAPEH samples. The obtained results showed that the CTE of OAPEH composite was about 18% less than that of OAP. Finally, a theoretical model was used based on first-order shear deformation theory (FSDT) to predict the critical bucking temperatures of the OAP and OAPEH composite plates. It was shown that in the absence of mechanical load, the critical buckling temperatures of OAPEH composite plates were higher than those of OAP composites, such that the difference between the buckling temperatures increased with the increase of thickness. On the contrary, the positive effect of CTE reduction on the buckling temperature decreased by raising the axial compressive mechanical load on the composite plates which can be assigned to the reduction of stiffness after the incorporation of ESP. The results of present study generally stated that a suitable combination of AF, PP, ESP, and HNT can result in a relatively optimal and environmentally friendly composite with proper flame and thermal buckling resistance with no significant decline in the stiffness.

A Study to Determine the Effectsiveness of Severance Hospice Home Care Program (호스피스케어에 대한 평가 연구 - 세브란스호스피스 중심으로)

  • Kingsley, Marian R.N.;Cho, Won-Jung;Kim, Cho-Ja;Lee, Won-Hee;Yoo, Ji-Soo
    • The Korean Nurse
    • /
    • v.29 no.4
    • /
    • pp.51-72
    • /
    • 1990
  • The purpose of this study was to determine whether Severance Hospice Home Care Pro gram was able to meet its objectives. This was done in order to show in detail the effects of hospice home care on the quality of life of terminally ill patients and to provide rationale for setting up more hospice home care programs in korea. The results of the study were as follows: The subjects of the study were 100 terminally ill patients who hnd died 'while in the hospice program and 64 family members who were registered with Severance Hospice Home Care Program between march 1988 and Feb. 1990. The nursing needs of these terminally ill patients were assessed by the nursing records of these patients. The need for pain control(82%) was the highest nursing need so far as the physical aspects were concerned. This was followed by poor appetite(37%), 8 dyspnea(34%), nausea and vomiting(30%) in that order of frequency. In reqard to spiritual needs, the need for religious' support was also high at 72%. Their main psychological symptoms were anxiety and fear(34% ). Burn-out was a major problem for 44% of the family members. The psychological process experiencel by the terminal ill patients was compared to the dying process, described by Kiibler Ross. In comparison of the five stages outlined by kubler Ross with the dying process of the subjects it was found that the subjects not only experienced the five stages but also experienced denial and doubt-fulness or denial with acceptance or acceptance with the expectation of a miracle. But rather than acceptance of the dying process, giving up was a frequent end point of the psychological process, of the subjects. However, when the combination of states was observed, most of the patients reached the state of acceptance in the dying process. It was difficult to identify a definite pattern of change in the psychological process of the subjects. Also it was difficult to identify the factors that influenced the psychological process. The symptoms of the terminally j]] subjects just before dying, that is, 3-4 days before dying included apparent signs of dying. These were a reduction of intake(77%), reduction of the amount of urination(63%), increase in sleeping time (64%) and acceptance of dying by patients and their families who had been unaccepting be before that time(66%). The primary care givers(family member's) degree of satisfaction with the care given to the patient by the hospice was 88.7%. The results of this study show that Severance Hospice Home Care Program had a positie effeet on the quality of life of the terminally ill patients and their family members as they faced the death of the patient. It can be seen from this study that there is an urgent need to extend hospice programs - in order to provide quality of care for terminally ill patient and their families. Based upon the reesults of this study several suggestions are presente as follows: 1) A follow up study should be carried out to identify the dying process as it is unique to Korea. 2) A comparison should be made of other hospice care programs. 3) A comparison study should- be made with subjects who do not receive any hospice care as compared to those who do by use of an experimental and control group methodology. 4) There is a need to determine a scientific method to adequeto measure the interventions carried out to meet the hospice patients nursing care needs. 5) A study should be made using quality research methodology to evaluate effects of hospiec care from the patients, their family members and the nurrse's perspective.

  • PDF

A Case Study on Characteristics of the Mathematics Gifted Children (수학영재의 특성에 관한 사례연구)

  • Kim, Min-Jung;Ryu, Sung-Rim
    • Education of Primary School Mathematics
    • /
    • v.10 no.1 s.19
    • /
    • pp.41-56
    • /
    • 2007
  • Related with the mathematics gifted children the situation of different case studies is the research which is limited in mathematics problem solving process of the most mathematics gifted children. The research which it sees hereupon observes from the scope which is wider the quality of the mathematics gifted children, before the hazard mathematics gifted children whom it sees enter into the mathematics gifted children education center unit life and life after studying living and dismissal of a class from the general school, namely for their general life it leads compared to attitude it observes the reporter it does a quality. For a what kind of interest in the mathematics gifted children, the research leads the family or general class, from the gifted children education center it has it considers encouragement, map and to give a help to good mathematics gifted children education activation, it does. It will reach and to respect with afterwards it set a same three research problem. First, before entering into the mathematics gifted children education center, are the mathematics gifted children what kind of quality? Second, Are the mathematics gifted children what kind of quality for general school hour? Third, Are the mathematics gifted children what kind of quality after dismissal of a class after hour? Being selected in the hazard gifted children education center which solves an up research problem, simple characteristic and approach ease characteristic, by the condition of the permission possibility back it selected 2 person gifted children school boxes which are coming and going. And, before entering into these mathematics gifted children education center, studying life from the general school, life after dismissal of a class it will extend at 1 years, various recording it will ask and it collected direct observation and interview it led against their quality it analyzed. It shared the result which it analyzes with emotional quality, studying conduct qualities, general qualities of the mathematics gifted children and qualities of mathematics gifted children parents. Studies level of the mathematics gifted children parents high facility when them are young from, the interest and helping out which it has were considerable, to advance with the direction where in order for always with great disaster them are proper the map it did. In general quality of the mathematics gifted children from young age the ability which finds a language and a possibility concept superiorly the ability which expresses the thought of oneself logically was superior, the competitive spirit was high, it liked it came reading, a leader role, to reveal a deepening school with the fact that it comes and goes. Also it will burn with their studying conduct quality and it will roll and it did deeply and it arranged knot eagerly, accomplishing which is superior from the field which is various it showed, the originality was superior, the subject attachment power was high quite, oneself it studies it has a devotion the possibility of knowing it was. And, the social characteristic of the friends and is good with their emotional quality and it does there is own reflection and an encouragement at any time and also a confidence, but just as good as the stress also it receives the possibility of knowing it was to him.

  • PDF

Study of Dental Hygienist's Stress Degree and Adaptation Method (치과위생사의 스트레스 정도와 적응 방법에 관한 연구)

  • Gwon, Mi-Young;Jung, Mee-Hee
    • Journal of dental hygiene science
    • /
    • v.4 no.3
    • /
    • pp.133-140
    • /
    • 2004
  • It examines closely the occupation characteristic primary factor which the dentistry hygienic company field which is working to presence at a sickbed is undergoing the degree and from the research which it sees and it grasps the adaptation method against it gropes bitterly with development of the dentistry hygienic company individual to join in, it contributed in dentistry medical treatment service quality improvement and the research which tries to sleep it attempted. Currently the dentistry hygiene which works from Seoul and the condition area subject matter dentist unit, the dentistry hospital and the general hospital dentistry back it did in the object which it will burn. 116 issues which become frequency in question 120 it used SPSS 10.0 and it analyzed. Result of this study is as following. (1) Was expose that stress degree by factor feels about commonness on the whole, and angle prospects and support connection stress at company were the biggest item by item, and appeared as on the other hand relation connection stress with patient is the smallest. (2) Stress that stress degree by each receives in case of there are a lot of other businesses to characteristic businesses except appeared highest. On the other hand, was expose that feel the lowest stress degree an item that other a type of occupation and discord are. (3) 'Do action of that throw goods or closes the door bump' appeared article highest by short term adaptation method about stress, and 'Think and gives up by fate' appeared highest by special skill adaptation method. Short term adaptation method appeared high than special skill adaptation method on the whole but the difference appeared as is very small. (4) Stress degree comparison by general special quality was shown difference that stress by only dental hygiene administration of justice selection motive keeps in mind. (5) All of the result that compare short term, long term adaptation method about stress that feel new dental higienist apple career dental higienist same difference be, but displayed high result in same munhang. (6) Was expose that difference that keep in mind from all arguments in comparison of short term adaptation method by general special quality does not exist, on the other hand, comparison of long-term adaptation method displayed result that religion among only variable keeps in mind statistically.

  • PDF