WorldWideScience

Sample records for time spent investigating

  1. Investigating the tradeoffs between spatial resolution and diffusion sampling for brain mapping with diffusion tractography: time well spent?

    Science.gov (United States)

    Calabrese, Evan; Badea, Alexandra; Coe, Christopher L; Lubach, Gabriele R; Styner, Martin A; Johnson, G Allan

    2014-11-01

    Interest in mapping white matter pathways in the brain has peaked with the recognition that altered brain connectivity may contribute to a variety of neurologic and psychiatric diseases. Diffusion tractography has emerged as a popular method for postmortem brain mapping initiatives, including the ex-vivo component of the human connectome project, yet it remains unclear to what extent computer-generated tracks fully reflect the actual underlying anatomy. Of particular concern is the fact that diffusion tractography results vary widely depending on the choice of acquisition protocol. The two major acquisition variables that consume scan time, spatial resolution, and diffusion sampling, can each have profound effects on the resulting tractography. In this analysis, we determined the effects of the temporal tradeoff between spatial resolution and diffusion sampling on tractography in the ex-vivo rhesus macaque brain, a close primate model for the human brain. We used the wealth of autoradiography-based connectivity data available for the rhesus macaque brain to assess the anatomic accuracy of six time-matched diffusion acquisition protocols with varying balance between spatial and diffusion sampling. We show that tractography results vary greatly, even when the subject and the total acquisition time are held constant. Further, we found that focusing on either spatial resolution or diffusion sampling at the expense of the other is counterproductive. A balanced consideration of both sampling domains produces the most anatomically accurate and consistent results. Copyright © 2014 Wiley Periodicals, Inc.

  2. Time spent on television in European countries

    NARCIS (Netherlands)

    Vergeer, M.R.M.; Coenders, M.T.A.; Scheepers, P.L.H.; Konig, R.P.; Nelissen, P.W.M.; Huysmans, F.J.M.

    2009-01-01

    This study aims to explain the variation in time spent on watching television in 15 European Union countries, using determinants defined at the individual level, and characteristics defined at the national level, such as the number of channels and nature of the television supply. The results of the

  3. Photoprotection by sunscreen depends on time spent on application.

    Science.gov (United States)

    Heerfordt, Ida M; Torsnes, Linnea R; Philipsen, Peter A; Wulf, Hans Christian

    2018-03-01

    To be effective, sunscreens must be applied in a sufficient quantity and reapplication is recommended. No previous study has investigated whether time spent on sunscreen application is important for the achieved photoprotection. To determine whether time spent on sunscreen application is related to the amount of sunscreen used during a first and second application. Thirty-one volunteers wearing swimwear applied sunscreen twice in a laboratory environment. Time spent and the amount of sunscreen used during each application was measured. Subjects' body surface area accessible for sunscreen application (BSA) was estimated from their height, weight and swimwear worn. The average applied quantity of sunscreen after each application was calculated. Subjects spent on average 4 minutes and 15 seconds on the first application and approximately 85% of that time on the second application. There was a linear relationship between time spent on application and amount of sunscreen used during both the first and the second application (P applications. After the first application, subjects had applied a mean quantity of sunscreen of 0.71 mg/cm 2 on the BSA, and after the second application, a mean total quantity of 1.27 mg/cm 2 had been applied. We found that participants applied a constant amount of sunscreen per minute during both a first and a second application. Measurement of time spent on application of sunscreen on different body sites may be useful in investigating the distribution of sunscreen in real-life settings. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. 5 CFR 551.422 - Time spent traveling.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Time spent traveling. 551.422 Section 551... Activities § 551.422 Time spent traveling. (a) Time spent traveling shall be considered hours of work if: (1... who is permitted to use an alternative mode of transportation, or an employee who travels at a time...

  5. 5 CFR 551.425 - Time spent receiving medical attention.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Time spent receiving medical attention... Relation to Other Activities § 551.425 Time spent receiving medical attention. (a) Time spent waiting for and receiving medical attention for illness or injury shall be considered hours of work if: (1) The...

  6. Investigation of novel spent fuel verification system for safeguard application

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Haneol; Yim, Man-Sung [KAIST, Daejeon (Korea, Republic of)

    2016-10-15

    Radioactive waste, especially spent fuel, is generated from the operation of nuclear power plants. The final stage of radioactive waste management is disposal which isolates radioactive waste from the accessible environment and allows it to decay. The safety, security, and safeguard of a spent fuel repository have to be evaluated before its operation. Many researchers have evaluated the safety of a repository. These researchers calculated dose to public after the repository is closed depending on their scenario. Because most spent fuel repositories are non-retrievable, research on security or safeguards of spent fuel repositories have to be performed. Design based security or safeguard have to be developed for future repository designs. This study summarizes the requirements of future spent fuel repositories especially safeguards, and suggests a novel system which meets the safeguard requirements. Applying safeguards to a spent fuel repository is becoming increasingly important. The future requirements for a spent fuel repository are suggested by several expert groups, such as ASTOR in IAEA. The requirements emphasizes surveillance and verification. The surveillance and verification of spent fuel is currently accomplished by using the Cerenkov radiation detector while spent fuel is being stored in a fuel pool. This research investigated an advanced spent fuel verification system using a system which converts spent fuel radiation into electricity. The system generates electricity while it is conveyed from a transportation cask to a disposal cask. The electricity conversion system was verified in a lab scale experiment using an 8.51GBq Cs-137 gamma source.

  7. Investigation of novel spent fuel verification system for safeguard application

    International Nuclear Information System (INIS)

    Lee, Haneol; Yim, Man-Sung

    2016-01-01

    Radioactive waste, especially spent fuel, is generated from the operation of nuclear power plants. The final stage of radioactive waste management is disposal which isolates radioactive waste from the accessible environment and allows it to decay. The safety, security, and safeguard of a spent fuel repository have to be evaluated before its operation. Many researchers have evaluated the safety of a repository. These researchers calculated dose to public after the repository is closed depending on their scenario. Because most spent fuel repositories are non-retrievable, research on security or safeguards of spent fuel repositories have to be performed. Design based security or safeguard have to be developed for future repository designs. This study summarizes the requirements of future spent fuel repositories especially safeguards, and suggests a novel system which meets the safeguard requirements. Applying safeguards to a spent fuel repository is becoming increasingly important. The future requirements for a spent fuel repository are suggested by several expert groups, such as ASTOR in IAEA. The requirements emphasizes surveillance and verification. The surveillance and verification of spent fuel is currently accomplished by using the Cerenkov radiation detector while spent fuel is being stored in a fuel pool. This research investigated an advanced spent fuel verification system using a system which converts spent fuel radiation into electricity. The system generates electricity while it is conveyed from a transportation cask to a disposal cask. The electricity conversion system was verified in a lab scale experiment using an 8.51GBq Cs-137 gamma source

  8. SOCIAL INTEGRATION: TESTING ANTECEDENTS OF TIME SPENT ONLINE

    Directory of Open Access Journals (Sweden)

    Lily Suriani Mohd Arif

    2013-07-01

    Full Text Available The literature on the relationship of social integration and time spent onlineprovides conflicting evidence of the relationship of social integration with timespent online. The study identifies and highlightsthe controversy and attempts toclarify the relationship of social integration withtime spent online bydecomposing the construct social integration into its affective and behavioraldimensions . Thestudy tests antecedents and effects of time spent online in arandom sample of senior level undergraduate students at a public university inMalaysia. The findings indicated that while self-report measures of behavioralsocial integration did not predict time spent online, and, the affective socialintegration had an inverse relationship with time spent online.

  9. Site investigations for the disposal of spent fuel - investigation program

    International Nuclear Information System (INIS)

    Aeikaes, Timo

    1985-11-01

    The Industrial Power Company Ltd (TVO) is making preparations for the final disposal of spent nuclear fuel into the Finnish bedrock. The revised site investigation program for the years 1986-2010 is presented in this report. The objectives and activities in the near future are described in more detail. The main objectives and frame programs for the investigations in the more distant future are described. The program planning of these investigations are being developed in the preceding site investigations. The investigations for the site selection are divided into four phases: 1983-1985 selection of the investigation areas, preparations for the field investigations, drilling and investigations in a deep test borehole; 1986-1992 preliminary site investigations in 5-10 investigation areas; 1993-2000 detailed site investigations in 2-3 investigation areas. Site selection in the year 2000; 2001-2010 complementary investigations on the selected site. The first investigation phase will be carried out as planned. In this phase a 1001 m deep test borehole was drilled at Lavia in western Finland. With the investigations in the borehole and related development work, preparations were made for the future field investigations. The equipment and investigation methods are being developed during the site investigations. The equipment for taking groundwater samples and the unit for hydraulic testing have been developed. In the future the emphasis in the work will be in developing equipment for monitoring of the hydraulic head and measuring the volumetric flow. In groundwater sampling the present procedure can be improved by adding the test for the in-situ measurements. The results of the field investigations will be stored and processed in a centralized data base. The data base will transmit the results for the interpretation and then the interpreted results transmitted for model calculations and reporting. The cost estimate for the investigations in 1986-2010 is 110-125 million

  10. Investigation of Positional Differences in Fitness of Male University Ice Hockey Players and the Frequency, Time Spent and Heart Rate of Movement Patterns during Competition

    Directory of Open Access Journals (Sweden)

    Joel Jackson

    2017-07-01

    Full Text Available Background:  Men’s university ice hockey has received little scientific attention over the past 30 years, a time in which the traits of the players and the demands of the game have evolved.  Objectives: This study compared the physiological characteristics of university ice hockey players and examined the frequency and duration of the different movement patterns and heart rate (HR responses during competition. Methods: Twenty male ice hockey players from the same team ( age ± SD = 22±2 years underwent a fitness evaluation and were filmed and HR monitored during regular season games. Results: Forwards and defense had similar fitness and only differed on % fatigue index and peak heart during on-ice sprinting (P<0.05. Defense stood, glided and skated backwards more than forwards and forwards skated at a moderate intensity and glided forward more than defense (P<0.05. All players spent the majority of game time gliding forward (60% of the time followed by skating forward at a moderate intensity (17% and standing with little movement (9%. Average HR during the game reached 96 and 92 % and peak HR was 100 and 96 % of maximum in forwards and defense, respectively. Conclusions: Male university hockey players present with a high level of physical fitness in a variety of categories with few differences between forwards and defense. Movement patterns during games suggest that players are performing low to moderate intensity on-ice activities the majority of the time. Paradoxically, HR continues to climb to near maximum during on ice shifts.

  11. Optimization of time and location dependent spent nuclear fuel storage capacity

    International Nuclear Information System (INIS)

    Macek, V.

    1977-01-01

    A linear spent fuel storage model is developed to identify cost-effective spent nuclear fuel storage strategies. The purpose of this model is to provide guidelines for the implementation of the optimal time-dependent spent fuel storage capacity expansion in view of the current economic and regulatory environment which has resulted in phase-out of the closed nuclear fuel cycle. Management alternatives of the spent fuel storage backlog, which is created by mismatch between spent fuel generation rate and spent fuel disposition capability, are represented by aggregate decision variables which describe the time dependent on-reactor-site and off-site spent fuel storage capacity additions, and the amount of spent fuel transferred to off-site storage facilities. Principal constraints of the model assure determination of cost optimal spent fuel storage expansion strategies, while spent fuel storage requirements are met at all times. A detailed physical and economic analysis of the essential components of the spent fuel storage problem, which precedes the model development, assures its realism. The effects of technological limitations on the on-site spent fuel storage expansion and timing of reinitiation of the spent fuel reprocessing on optimal spent fuel storage capacity expansion are investigated. The principal results of the study indicate that (a) expansion of storage capacity beyond that of currently planned facilities is necessary, and (b) economics of the post-reactor fuel cycle is extremely sensitive to the timing of reinitiation of spent fuel reprocessing. Postponement of reprocessing beyond mid-1982 may result in net negative economic liability of the back end of the nuclear fuel cycle

  12. Adolescent Depression and Time Spent with Parents and Siblings

    Science.gov (United States)

    Desha, Laura N.; Nicholson, Jan M.; Ziviani, Jenny M.

    2011-01-01

    This study examines adolescent depressive symptoms and the quantity and quality of time spent by adolescents with their parents and siblings. We use measures of the quality of relationships with parents and siblings as proxy indicators for the quality of time spent with these social partners. The study emphasizes the salience of parent…

  13. Time Well Spent? Relating Television Use to Children’s Free-Time Activities

    Science.gov (United States)

    Vandewater, Elizabeth A.; Bickham, David S.; Lee, June H.

    2010-01-01

    OBJECTIVES This study assessed the claim that children’s television use interferes with time spent in more developmentally appropriate activities. METHODS Data came from the first wave of the Child Development Supplement, a nationally representative sample of children aged 0 to 12 in 1997 (N = 1712). Twenty-four-hour time-use diaries from 1 randomly chosen weekday and 1 randomly chosen weekend day were used to assess children’s time spent watching television, time spent with parents, time spent with siblings, time spent reading (or being read to), time spent doing homework, time spent in creative play, and time spent in active play. Ordinary least squares multiple regression was used to assess the relationship between children’s television use and time spent pursuing other activities. RESULTS Results indicated that time spent watching television both with and without parents or siblings was negatively related to time spent with parents or siblings, respectively, in other activities. Television viewing also was negatively related to time spent doing homework for 7- to 12-year-olds and negatively related to creative play, especially among very young children (younger than 5 years). There was no relationship between time spent watching television and time spent reading (or being read to) or to time spent in active play. CONCLUSIONS The results of this study are among the first to provide empirical support for the assumptions made by the American Academy of Pediatrics in their screen time recommendations. Time spent viewing television both with and without parents and siblings present was strongly negatively related to time spent interacting with parents or siblings. Television viewing was associated with decreased homework time and decreased time in creative play. Conversely, there was no support for the widespread belief that television interferes with time spent reading or in active play. PMID:16452327

  14. Cooling-time determination of spent fuel

    International Nuclear Information System (INIS)

    Hsue, S.T.; Hatcher, C.R.; Kaieda, K.

    1979-01-01

    Two methods to determine the cooling time using data from high-resolution gamma-ray measurements are discussed; one is useful when the irradiation history information is available, the other when the irradiation history is not available. We have applied both methods and found that the cooling time can be determined to within an average of 3% and 4.1%, respectively

  15. Do Workplace Flexibility Policies Influence Time Spent in Domestic Labor?

    Science.gov (United States)

    Noonan, Mary C.; Estes, Sarah Beth; Glass, Jennifer L.

    2007-01-01

    Using data from a U.S. midwestern sample of mothers and fathers, the authors examine whether using workplace flexibility policies alters time spent in housework and child care. They hypothesize that an individual's policy use will lead to more time in domestic labor and that his or her spouse's policy use will lead to less time in domestic labor.…

  16. Time Spent in Indirect Nursing Care

    Science.gov (United States)

    1983-09-01

    unable to recognize what needs to be done, or lacking motivation . Likewise, head nurses may spend too much time giving Cdirect care (14.5%). Perhaps more...of the head nurse time might be redirected to teaching, supervising, and motivating other staff members. Although the objective data are reliable, the...S7 9 1 a NO .06 P4 Z& V- N. 4 1 oe a ~~3 00 0I xI %A II I-~~~- Lai - E, zCk u atII C.p UA a 5 P44 d4. Ps4 .- U)2 co Ili L I ao r40 ey . 1a ,o 01 𔃾K

  17. Estimated time spent on preventive services by primary care physicians

    Directory of Open Access Journals (Sweden)

    Gradison Margaret

    2008-12-01

    Full Text Available Abstract Background Delivery of preventive health services in primary care is lacking. One of the main barriers is lack of time. We estimated the amount of time primary care physicians spend on important preventive health services. Methods We analyzed a large dataset of primary care (family and internal medicine visits using the National Ambulatory Medical Care Survey (2001–4; analyses were conducted 2007–8. Multiple linear regression was used to estimate the amount of time spent delivering each preventive service, controlling for demographic covariates. Results Preventive visits were longer than chronic care visits (M = 22.4, SD = 11.8, M = 18.9, SD = 9.2, respectively. New patients required more time from physicians. Services on which physicians spent relatively more time were prostate specific antigen (PSA, cholesterol, Papanicolaou (Pap smear, mammography, exercise counseling, and blood pressure. Physicians spent less time than recommended on two "A" rated ("good evidence" services, tobacco cessation and Pap smear (in preventive visits, and one "B" rated ("at least fair evidence" service, nutrition counseling. Physicians spent substantial time on two services that have an "I" rating ("inconclusive evidence of effectiveness", PSA and exercise counseling. Conclusion Even with limited time, physicians address many of the "A" rated services adequately. However, they may be spending less time than recommended for important services, especially smoking cessation, Pap smear, and nutrition counseling. Future research is needed to understand how physicians decide how to allocate their time to address preventive health.

  18. Reviewing interval cancers: Time well spent?

    International Nuclear Information System (INIS)

    Gower-Thomas, Kate; Fielder, Hilary M.P.; Branston, Lucy; Greening, Sarah; Beer, Helen; Rogers, Cerilan

    2002-01-01

    OBJECTIVES: To categorize interval cancers, and thus identify false-negatives, following prevalent and incident screens in the Welsh breast screening programme. SETTING: Breast Test Wales (BTW) Llandudno, Cardiff and Swansea breast screening units. METHODS: Five hundred and sixty interval breast cancers identified following negative mammographic screening between 1989 and 1997 were reviewed by eight screening radiologists. The blind review was achieved by mixing the screening films of women who subsequently developed an interval cancer with screen negative films of women who did not develop cancer, in a ratio of 4:1. Another radiologist used patients' symptomatic films to record a reference against which the reviewers' reports of the screening films were compared. Interval cancers were categorized as 'true', 'occult', 'false-negative' or 'unclassified' interval cancers or interval cancers with minimal signs, based on the National Health Service breast screening programme (NHSBSP) guidelines. RESULTS: Of the classifiable interval films, 32% were false-negatives, 55% were true intervals and 12% occult. The proportion of false-negatives following incident screens was half that following prevalent screens (P = 0.004). Forty percent of the seed films were recalled by the panel. CONCLUSIONS: Low false-negative interval cancer rates following incident screens (18%) versus prevalent screens (36%) suggest that lower cancer detection rates at incident screens may have resulted from fewer cancers than expected being present, rather than from a failure to detect tumours. The panel method for categorizing interval cancers has significant flaws as the results vary markedly with different protocol and is no more accurate than other, quicker and more timely methods. Gower-Thomas, K. et al. (2002)

  19. Time Spent on the Internet and Adolescent Blood Pressure

    Science.gov (United States)

    Cassidy-Bushrow, Andrea E.; Johnson, Dayna A.; Peters, Rosalind M.; Burmeister, Charlotte; Joseph, Christine L. M.

    2015-01-01

    Internet use is nearly ubiquitous among adolescents. Growing evidence suggests heavy Internet use negatively impacts health, yet the relationship between time spent on the Internet and adolescent blood pressure (BP) is unknown. We examined the association between Internet use and elevated BP in a racially diverse cross-sectional sample of 331…

  20. Reevaluation of time spent indoors used for exposure dose assessment

    International Nuclear Information System (INIS)

    Hirose, Katsumi; Fujimoto, Kenzo

    2016-01-01

    A time spent indoors of sixteen hours per day (indoor occupancy factor: 0.67) has been used to assess the radiation dose of residents who spend daily life in the area contaminated due to the nuclear accident in Japan. However, much longer time is considered to be spent indoors for recent modern life. United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has been used an indoor occupancy factor of 0.8 since 1977 and a few reports suggested much higher indoor occupancy factors. Therefore it is important to reevaluate the indoor occupancy factor using current available survey data in Japan, such as 'NHK 2010 National Time Use Survey' and 'Survey on Time Use and Leisure Activities' of Statistics Bureau with certain assumption of time spent indoors in each daily activity. The total time spent indoors in a day is calculated to be 20.2 hours and its indoor occupancy factor is 0.84. Much lower indoor occupancy factors were derived from the survey data by Statistics Bureau for 10 to 14 and 15 to 19 years old groups and farmers who spend most of their time outdoors although present estimated indoor occupancy factor of 0.84 is still lower than those found in some of the relevant reports. A rounded indoor occupancy factor of 0.80 might be the appropriate conservative reference value to be used for the dose estimation of people who live in radioactively contaminated areas and for other relevant purposes of exposure assessment, taken into consideration the present results and values reported in United States Environmental Protection Agency (US EPA) and UNSCEAR. (author)

  1. Time spent on home food preparation and indicators of healthy eating.

    Science.gov (United States)

    Monsivais, Pablo; Aggarwal, Anju; Drewnowski, Adam

    2014-12-01

    The amount of time spent on food preparation and cooking may have implications for diet quality and health. However, little is known about how food-related time use relates to food consumption and spending, either at restaurants or for food consumed at home. To quantitatively assess the associations among the amount of time habitually spent on food preparation and patterns of self-reported food consumption, food spending, and frequency of restaurant use. This was a cross-sectional study of 1,319 adults in a population-based survey conducted in 2008-2009. The sample was stratified into those who spent 2 hours/day on food preparation and cleanup. Descriptive statistics and multivariable regression models examined differences between time-use groups. Analyses were conducted in 2011-2013. Individuals who spent the least amount of time on food preparation tended to be working adults who placed a high priority on convenience. Greater amount of time spent on home food preparation was associated with indicators of higher diet quality, including significantly more frequent intake of vegetables, salads, fruits, and fruit juices. Spending food preparation was associated with significantly more money spent on food away from home and more frequent use of fast food restaurants compared to those who spent more time on food preparation. The findings indicate that time might be an essential ingredient in the production of healthier eating habits among adults. Further research should investigate the determinants of spending time on food preparation. Copyright © 2014 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  2. [Problematic Internet use, time spent online and personality traits].

    Science.gov (United States)

    Laconi, S; Andréoletti, A; Chauchard, E; Rodgers, R F; Chabrol, H

    2016-06-01

    Internet addiction or problematic Internet use is a recent and increasingly recognized disorder which has been consistently associated with many psychiatric disorders, adding to the documented negative consequences of problematic Internet use. However, very few studies have examined the relationship between problematic Internet use and personality traits and none in a French sample. Moreover, those which have evaluated this relationship have mainly been conducted on small samples. The main goal of our study was to explore the relationship between problematic Internet use, time spent online and personality traits in a French sample, taking into account the presence of depressive symptoms, and gender. A sample of 276 participants aged from 18 to 50 (M=28; SD=8.9) completed a questionnaire assessing problematic Internet use, time spent online, the presence of ten personality traits and depressive symptoms. Our results revealed significant differences between genders. Among men, problematic Internet use was associated with personality clusters A and B while in women no cluster or personality traits were associated. Time spent online was predicted by schizoid personality traits among men and avoidant personality traits among women. Our results indicate that cluster A (schizoid and schizotypal) and cluster B traits (borderline and antisocial) play a more important role in problematic Internet use than cluster C traits among men. Differences between men and women regarding the relationships between personality traits, time online and problematic Internet use may be related to differences in the activities engaged in by men and women online. We observed that communication websites use was more prevalent among women while erotic, gambling and shopping websites use was more prevalent among men suggesting that the characteristics of problematic Internet use may vary according to gender. Few studies have examined the relationship between problematic Internet use, time spent

  3. Investigation of the condition of spent-fuel pool components

    International Nuclear Information System (INIS)

    Kustas, F.M.; Bates, S.O.; Opitz, B.E.; Johnson, A.B. Jr.; Perez, J.M. Jr.; Farnsworth, R.K.

    1981-09-01

    It is currently projected that spent nuclear fuel, which is discharged from the reactor and then stored in water pools, may remain in those pools for several decades. Other studies have addressed the expected integrity of the spent fuel during extended water storage; this study assesses the integrity of metallic spent fuel pool components. Results from metallurgical examinations of specimens taken from stainless steel and aluminum components exposed in spent fuel pools are presented. Licensee Event Reports (LERs) relating to problems with spent fuel components were assessed and are summarized to define the types of operational problems that have occurred. The major conclusions of this study are: aluminum and stainless steel spent fuel pool components have a good history of performance in both deionized and borated water pools. Although some operational problems involving pool components have occurred, these problems have had minimal impacts

  4. Investigation of the condition of spent-fuel pool components

    Energy Technology Data Exchange (ETDEWEB)

    Kustas, F.M.; Bates, S.O.; Opitz, B.E.; Johnson, A.B. Jr.; Perez, J.M. Jr.; Farnsworth, R.K.

    1981-09-01

    It is currently projected that spent nuclear fuel, which is discharged from the reactor and then stored in water pools, may remain in those pools for several decades. Other studies have addressed the expected integrity of the spent fuel during extended water storage; this study assesses the integrity of metallic spent fuel pool components. Results from metallurgical examinations of specimens taken from stainless steel and aluminum components exposed in spent fuel pools are presented. Licensee Event Reports (LERs) relating to problems with spent fuel components were assessed and are summarized to define the types of operational problems that have occurred. The major conclusions of this study are: aluminum and stainless steel spent fuel pool components have a good history of performance in both deionized and borated water pools. Although some operational problems involving pool components have occurred, these problems have had minimal impacts.

  5. It takes longer than you think: librarian time spent on systematic review tasks*

    Science.gov (United States)

    Bullers, Krystal; Howard, Allison M.; Hanson, Ardis; Kearns, William D.; Orriola, John J.; Polo, Randall L.; Sakmar, Kristen A.

    2018-01-01

    Introduction The authors examined the time that medical librarians spent on specific tasks for systematic reviews (SRs): interview process, search strategy development, search strategy translation, documentation, deliverables, search methodology writing, and instruction. We also investigated relationships among the time spent on SR tasks, years of experience, and number of completed SRs to gain a better understanding of the time spent on SR tasks from time, staffing, and project management perspectives. Methods A confidential survey and study description were sent to medical library directors who were members of the Association of Academic Health Sciences Libraries as well as librarians serving members of the Association of American Medical Colleges or American Osteopathic Association. Results Of the 185 participants, 143 (77%) had worked on an SR within the last 5 years. The number of SRs conducted by participants during their careers ranged from 1 to 500, with a median of 5. The major component of time spent was on search strategy development and translation. Average aggregated time for standard tasks was 26.9 hours, with a median of 18.5 hours. Task time was unrelated to the number of SRs but was positively correlated with years of SR experience. Conclusion The time required to conduct the librarian’s discrete tasks in an SR varies substantially, and there are no standard time frames. Librarians with more SR experience spent more time on instruction and interviews; time spent on all other tasks varied widely. Librarians also can expect to spend a significant amount of their time on search strategy development, translation, and writing. PMID:29632442

  6. Heat transfer investigations within dry spent fuel casks

    International Nuclear Information System (INIS)

    Nitsche, F.

    1986-07-01

    For studying the heat transfer processes and predicting the maximum spent fuel element surface temperature in a spent fuel assembly (SFA) transported in a dry cask, model experiments have been performed with a gas-filled model cask containing a simplified electrically heated model of a WWER-type SFA with 90 fuel elements. The temperature distribution of the SFA model is measured for different heat rates under vacuum in the model cask, and under normal pressure and overpressure (0.1 ... 0.7 MPa) for several cooling gases (air, argon, helium) in order to separately investigate heat transfer processes by radiation and convection/conduction. The measuring results were compared with the calculations. Computer programmes as well as simplified calculation methods for temperature prediction were developed and checked. The results obtained are also useful for thermal analyses in the field of the dry storage of SFAs in a cask or can. Specifically it was found that: The heat removal from the SFA can be considerably improved by increasing the internal cask pressure or by using helium as coolant. The radiant heat exchange in the SFA model can be calculated with sufficient accuracy by means of a computer programme developed in 1978 or by means of a simplified analytical representation shown in the final report. Both methods are directly applicable to the original SFA and useful in order to approximately calculate the maximum SFE surface temperature under normal pressure, if the fraction of heat transferred by radiation is allowed for. For the calculation of the total heat transfer a computer programme was developed and verified, which completely permits the temperature prediction of the SFA model in dependence on heat rate, type of gaseous coolant and coolant pressure. This computer programme can be directly applied to the original SFA for the calculation of the maximum SFE surface temperature

  7. Investigation on spent fuel characteristics of reduced-moderation water reactor (RMWR)

    International Nuclear Information System (INIS)

    Fukaya, Y.; Okubo, T.; Uchikawa, S.

    2008-01-01

    The spent fuel characteristics of the reduced-moderation water reactor (RMWR) have been investigated using the SWAT and ORIGEN codes. RMWR is an advanced LWR concept for plutonium recycling by using the MOX fuel. In the code calculation, the ORIGEN libraries such as one-group cross-section data prepared for RMWR were necessary. Since there were no open libraries for RMWR, they were produced in this study by using the SWAT code. New libraries based on the heterogeneous core modeling in the axial direction and with the variable actinide cross-section (VXSEC) option were produced and selected as the representative ORIGEN libraries for RMWR. In order to investigate the characteristics of the RMWR spent fuel, the decay heat, the radioactivity and the content of each nuclide were evaluated with ORIGEN using these libraries. In this study, the spent fuel characteristics of other types of reactors, such as PWR, BWR, high burn-up PWR, full-MOX-PWR, full-MOX-BWR and FBR, were also evaluated with ORIGEN. It has been found that about a half of the decay heat of the RMWR spent fuel comes from the actinides nuclides. It is the same with the radioactivity. The decay heat and the radioactivity of the RMWR spent fuel are lower than those of full-MOX-LWRs and FBR, and are the same level as those of the high burn-up PWR. The decay heat and the radioactivity from the fission products (FPs) in the spent fuel mainly depend on the burn-up and the burn-up time rather than the reactor type. Therefore, the decay heat and the radioactivity from FPs in the RMWR spent fuel are smaller, reflecting its relatively long burn-up time resulted from its core characteristics with the high conversion ratio. The radioactivity from the actinides in the spent fuel mainly depends on the 241 Pu content in the initial fuel, and the decay heat mainly depends on 238 Pu and 244 Cm. The contribution of 244 Cm is much smaller in RMWR than in MOX-LWRs because of the difference in the spectrum. In addition, from

  8. Investigation on spent fuel characteristics of reduced-moderation water reactor (RMWR)

    Energy Technology Data Exchange (ETDEWEB)

    Fukaya, Y. [Advanced Nuclear System Research and Development Directorate, Japan Atomic Energy Agency (JAEA), Oarai-machi, Ibaraki-ken 311-1393 (Japan)], E-mail: fukaya.yuji@jaea.go.jp; Okubo, T.; Uchikawa, S. [Advanced Nuclear System Research and Development Directorate, Japan Atomic Energy Agency (JAEA), Oarai-machi, Ibaraki-ken 311-1393 (Japan)

    2008-07-15

    The spent fuel characteristics of the reduced-moderation water reactor (RMWR) have been investigated using the SWAT and ORIGEN codes. RMWR is an advanced LWR concept for plutonium recycling by using the MOX fuel. In the code calculation, the ORIGEN libraries such as one-group cross-section data prepared for RMWR were necessary. Since there were no open libraries for RMWR, they were produced in this study by using the SWAT code. New libraries based on the heterogeneous core modeling in the axial direction and with the variable actinide cross-section (VXSEC) option were produced and selected as the representative ORIGEN libraries for RMWR. In order to investigate the characteristics of the RMWR spent fuel, the decay heat, the radioactivity and the content of each nuclide were evaluated with ORIGEN using these libraries. In this study, the spent fuel characteristics of other types of reactors, such as PWR, BWR, high burn-up PWR, full-MOX-PWR, full-MOX-BWR and FBR, were also evaluated with ORIGEN. It has been found that about a half of the decay heat of the RMWR spent fuel comes from the actinides nuclides. It is the same with the radioactivity. The decay heat and the radioactivity of the RMWR spent fuel are lower than those of full-MOX-LWRs and FBR, and are the same level as those of the high burn-up PWR. The decay heat and the radioactivity from the fission products (FPs) in the spent fuel mainly depend on the burn-up and the burn-up time rather than the reactor type. Therefore, the decay heat and the radioactivity from FPs in the RMWR spent fuel are smaller, reflecting its relatively long burn-up time resulted from its core characteristics with the high conversion ratio. The radioactivity from the actinides in the spent fuel mainly depends on the {sup 241}Pu content in the initial fuel, and the decay heat mainly depends on {sup 238}Pu and {sup 244}Cm. The contribution of {sup 244}Cm is much smaller in RMWR than in MOX-LWRs because of the difference in the spectrum

  9. The Relationship between Motivation, Learning Approaches, Academic Performance and Time Spent

    Science.gov (United States)

    Everaert, Patricia; Opdecam, Evelien; Maussen, Sophie

    2017-01-01

    Previous literature calls for further investigation in terms of precedents and consequences of learning approaches (deep learning and surface learning). Motivation as precedent and time spent and academic performance as consequences are addressed in this paper. The study is administered in a first-year undergraduate course. Results show that the…

  10. Time Spent on the Internet and Adolescent Blood Pressure.

    Science.gov (United States)

    Cassidy-Bushrow, Andrea E; Johnson, Dayna A; Peters, Rosalind M; Burmeister, Charlotte; Joseph, Christine L M

    2015-10-01

    Internet use is nearly ubiquitous among adolescents. Growing evidence suggests heavy Internet use negatively impacts health, yet the relationship between time spent on the Internet and adolescent blood pressure (BP) is unknown. We examined the association between Internet use and elevated BP in a racially diverse cross-sectional sample of 331 healthy adolescents (ages 14-17 years). Heavy Internet use was defined as ≥ 2 hr/day, moderate use as Internet users had statistically significantly higher odds of elevated BP compared to light Internet users. School nurses can play an important role in preventing high BP through assessment of BP and other health behaviors including Internet use, and health teaching to individuals, student groups, faculty, and parents to increase awareness of the relationship between Internet use and health. © The Author(s) 2014.

  11. Associations between Parental and Friend Social Support and Children's Physical Activity and Time Spent outside Playing.

    Science.gov (United States)

    Loucaides, Constantinos A; Tsangaridou, Niki

    2017-01-01

    The purpose of this study was to examine the structural validity of a parent and a child questionnaire that assessed parental and friends' influences on children's physical activity and investigate the associations between the derived factors, physical activity, and time spent outside. Children ( N = 154, mean age = 11.7) and 144 of their parents completed questionnaires assessing parental and friends' influences on children's physical activity. Children wore a pedometer for six days. Exploratory factor analyses revealed four factors for the parental and five for the child's questionnaire that explained 66.71% and 63.85% of the variance, respectively. Five factors were significantly associated with physical activity and five significantly associated with time spent outside. Higher correlations were revealed between "general friend support," "friends' activity norms," and physical activity ( r = 0.343 and 0.333 resp., p friend support" and time spent outside ( r = 0.460, p parental and friends' influences on physical activity from both parents and children may provide a more complete picture of influences. Parents and friends seem to influence children's physical activity behavior and time spent outside, but friends' influences may have a stronger impact on children's behaviors.

  12. Time Spent in Home Production Activities by Married Couples and Single Adults with Children.

    Science.gov (United States)

    Douthitt, Robin A.

    1988-01-01

    A study found that, over time, married women employed full time have not decreased the time spent working in the home. Married men with young children have increased the time spent on home work. Single parents' time most closely resembled that of married women. (JOW)

  13. Time Spent on Social Network Sites and Psychological Well-Being: A Meta-Analysis.

    Science.gov (United States)

    Huang, Chiungjung

    2017-06-01

    This meta-analysis examines the relationship between time spent on social networking sites and psychological well-being factors, namely self-esteem, life satisfaction, loneliness, and depression. Sixty-one studies consisting of 67 independent samples involving 19,652 participants were identified. The mean correlation between time spent on social networking sites and psychological well-being was low at r = -0.07. The correlations between time spent on social networking sites and positive indicators (self-esteem and life satisfaction) were close to 0, whereas those between time spent on social networking sites and negative indicators (depression and loneliness) were weak. The effects of publication outlet, site on which users spent time, scale of time spent, and participant age and gender were not significant. As most included studies used student samples, future research should be conducted to examine this relationship for adults.

  14. Time Spent, Workload, and Student and Faculty Perceptions in a Blended Learning Environment

    Science.gov (United States)

    Schumacher, Christie; Arif, Sally

    2016-01-01

    Objective. To evaluate student perception and time spent on asynchronous online lectures in a blended learning environment (BLE) and to assess faculty workload and perception. Methods. Students (n=427) time spent viewing online lectures was measured in three courses. Students and faculty members completed a survey to assess perceptions of a BLE. Faculty members recorded time spent creating BLEs. Results. Total time spent in the BLE was less than the allocated time for two of the three courses by 3-15%. Students preferred online lectures for their flexibility, students’ ability to apply information learned, and congruence with their learning styles. Faculty members reported the BLE facilitated higher levels of learning during class sessions but noted an increase in workload. Conclusion. A BLE increased faculty workload but was well received by students. Time spent viewing online lectures was less than what was allocated in two of the three courses. PMID:27667839

  15. Teacher Time Spent on Student Health Issues and School Nurse Presence

    Science.gov (United States)

    Hill, Nina Jean; Hollis, Marianne

    2012-01-01

    Elementary school teacher time spent on student health issues and the relationship to school nurse services was the focus of this 2-year study. A cross-sectional design was used to survey traditional and exceptional (special needs) classroom teachers about the time they spent on health issues and their perception of school nurse presence. The…

  16. 48 CFR 852.271-72 - Time spent by counselee in counseling process.

    Science.gov (United States)

    2010-10-01

    ... counseling process. 852.271-72 Section 852.271-72 Federal Acquisition Regulations System DEPARTMENT OF... Clauses 852.271-72 Time spent by counselee in counseling process. As prescribed in 871.212, insert the following clause: Time Spent by Counselee in Counseling Process (APR 1984) The contractor agrees that no...

  17. Time spent in physical activity and sedentary behaviors on the working day: the American time use survey.

    Science.gov (United States)

    Tudor-Locke, Catrine; Leonardi, Claudia; Johnson, William D; Katzmarzyk, Peter T

    2011-12-01

    To determine time spent on the working day in sleep, work, sedentary behaviors, and light-, moderate-, and vigorous-intensity behaviors by occupation intensity. Data came from 30,758 working respondents to the 2003 to 2009 American Time Use Survey. Mean ± SEM time spent in work, sedentary behaviors, light-, moderate-, and vigorous-intensity activities, and sleep were computed by occupations classified as sedentary, light, moderate, and vigorous intensity. On average, approximately 32% of the 24-hour day was spent sleeping and approximately 31% was spent at work. Time spent in sedentary behaviors outside of work was higher, and light-intensity time was lower, with higher levels of intensity-defined occupation. Those employed in sedentary occupations were sedentary for approximately 11 hours per day, leaving little time to achieve recommended levels of physical activity for overall health.

  18. Developer’s time spent in a software project part using the SGD framework

    OpenAIRE

    Ciesluk, Simon

    2016-01-01

    Resource management is important for software projects to be successful. Time is one of these resources that needs to be managed. To do this you need to know how time resources are spent. Currently the existence of published material on time resources spent in a software project is almost none. In this thesis a research was conducted on how time resources are spent by an individual developer in a software project. The Self-Governance Developer framework was the tool used to gather these resou...

  19. Plan for spent fuel waste form testing for NNWSI [Nevada Nuclear Waste Storage Investigations

    International Nuclear Information System (INIS)

    Shaw, H.F.

    1987-11-01

    The purpose of spent fuel waste form testing is to determine the rate of release of radionuclides from failed disposal containers holding spent fuel, under conditions appropriate to the Nevada Nuclear Waste Storage Investigations (NNWSI) Project tuff repository. The information gathered in the activities discussed in this document will be used: to assess the performance of the waste package and engineered barrier system (EBS) with respect to the containment and release rate requirements of the Nuclear Regulatory Commission, as the basis for the spent fuel waste form source term in repository-scale performance assessment modeling to calculate the cumulative releases to the accessible environment over 10,000 years to determine compliance with the Environmental Protection Agency, and as the basis for the spent fuel waste form source term in repository-scale performance assessment modeling to calculate cumulative releases over 100,000 years as required by the site evaluation process specified in the DOE siting guidelines. 34 refs

  20. Birth weight and time spent in outdoor physical activity during adolescence.

    Science.gov (United States)

    Gopinath, Bamini; Hardy, Louise L; Baur, Louise A; Burlutsky, George; Mitchell, Paul

    2013-03-01

    We investigated the association between birth parameters (weight, length, and head circumference) and time spent in physical activity (outdoor and indoor) and screen time (TV viewing, computer, and videogame usage) among adolescents. A longitudinal cohort study surveyed 1794 children in 2004-2005 (median age = 12.7 yr), and 752 were resurveyed 5 yr later in 2009-2010 (age = 17-18 yr). Adolescents completed detailed activity questionnaires. Parents extracted birth parameter data from their child's health record booklet. After adjusting for age, sex, ethnicity, gestational age, parental education, home ownership, exposure to passive smoking, and body mass index, 12-yr-old children in the highest compared with the lowest quartile of birth weight spent on average approximately 56 and 62 min more in total (Ptrend = 0.02) and outdoor physical activity (Ptrend = 0.02) per week, respectively. Similarly, 12-yr-old children in the high (>4000 g) versus very low (adolescence. Hence, this could be part of the underlying mechanism between prenatal influences and future disease risk and could have possible clinical implications.

  1. Time Spent Outdoors, Depressive Symptoms, and Variation by Race and Ethnicity.

    Science.gov (United States)

    Beyer, Kirsten M M; Szabo, Aniko; Nattinger, Ann B

    2016-09-01

    Numerous studies have explored neighborhood environmental correlates of mental illnesses, presuming that the time individuals spend in their environment can confer benefit or harm based on environmental characteristics. However, few population-based studies have directly examined the relationship between time spent outdoors and mental health, and little work has been done to explore how experiences differ by race and ethnicity. Though some have proposed "doses of outdoor time" to improve health, the absence of information about the benefits conferred by particular "doses," and expected baseline levels of outdoor time, are needed to inform the development of recommendations and interventions. This study examined the relationship between time spent outdoors and depression among a population-based sample of American adults, characterized current levels of time spent outdoors by race and ethnicity, and examined how the relationship between time spent outdoors and depression varies by race and ethnicity. Descriptive statistics and survey regression models were used to examine data from the National Health and Nutrition Examination Survey for 2009-2012. Findings provide evidence that time spent outdoors is associated with fewer depressive symptoms, but this benefit may not be equally distributed by race and ethnicity. Descriptive analyses also reveal differences in time spent outdoors among different racial and ethnic groups. Study findings support the notion that increasing time spent outdoors may result in mental health benefits. However, this study questions whether that benefit is experienced equally among different groups, particularly given differences in occupational experiences and environmental characteristics of neighborhoods. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  2. Age at Menarche and Time Spent in Education: A Mendelian Randomization Study.

    Science.gov (United States)

    Gill, D; Del Greco M, F; Rawson, T M; Sivakumaran, P; Brown, A; Sheehan, N A; Minelli, C

    2017-09-01

    Menarche signifies the primary event in female puberty and is associated with changes in self-identity. It is not clear whether earlier puberty causes girls to spend less time in education. Observational studies on this topic are likely to be affected by confounding environmental factors. The Mendelian randomization (MR) approach addresses these issues by using genetic variants (such as single nucleotide polymorphisms, SNPs) as proxies for the risk factor of interest. We use this technique to explore whether there is a causal effect of age at menarche on time spent in education. Instruments and SNP-age at menarche estimates are identified from a Genome Wide Association Study (GWAS) meta-analysis of 182,416 women of European descent. The effects of instruments on time spent in education are estimated using a GWAS meta-analysis of 118,443 women performed by the Social Science Genetic Association Consortium (SSGAC). In our main analysis, we demonstrate a small but statistically significant causal effect of age at menarche on time spent in education: a 1 year increase in age at menarche is associated with 0.14 years (53 days) increase in time spent in education (95% CI 0.10-0.21 years, p = 3.5 × 10 -8 ). The causal effect is confirmed in sensitivity analyses. In identifying this positive causal effect of age at menarche on time spent in education, we offer further insight into the social effects of puberty in girls.

  3. Predicting Time Spent in Treatment in a Sample of Danish Survivors of Child Sexual Abuse.

    Science.gov (United States)

    Fletcher, Shelley; Elklit, Ask; Shevlin, Mark; Armour, Cherie

    2017-07-01

    The aim of this study was to identify significant predictors of length of time spent in treatment. In a convenience sample of 439 Danish survivors of child sexual abuse, predictors of time spent in treatment were examined. Assessments were conducted on a 6-month basis over a period of 18 months. A multinomial logistic regression analysis revealed that the experience of neglect in childhood and having experienced rape at any life stage were associated with less time in treatment. Higher educational attainment and being male were associated with staying in treatment for longer periods of time. These factors may be important for identifying those at risk of terminating treatment prematurely. It is hoped that a better understanding of the factors that predict time spent in treatment will help to improve treatment outcomes for individuals who are at risk of dropping out of treatment at an early stage.

  4. Time well spent? Assessing nursing-supply chain activities.

    Science.gov (United States)

    Ferenc, Jeff

    2010-02-01

    The amount of time nurses spend providing direct patient care seems to be continually eroding. So it's little wonder a survey conducted last year of critical care, OR nurses and nurse executives found that half of the 1600 respondents feel they spend too much time on supply chain duties. Most also said their supply chain duties impact patient safe ty and their ability to provide bedside care. Experts interviewed for this report believe it's time for supply chain leaders and nurses to develop a closer working partnership. Included are their recommendations to improve performance.

  5. Associations between Parental and Friend Social Support and Children’s Physical Activity and Time Spent outside Playing

    Directory of Open Access Journals (Sweden)

    Constantinos A. Loucaides

    2017-01-01

    Full Text Available The purpose of this study was to examine the structural validity of a parent and a child questionnaire that assessed parental and friends’ influences on children’s physical activity and investigate the associations between the derived factors, physical activity, and time spent outside. Children (N=154, mean age = 11.7 and 144 of their parents completed questionnaires assessing parental and friends’ influences on children’s physical activity. Children wore a pedometer for six days. Exploratory factor analyses revealed four factors for the parental and five for the child’s questionnaire that explained 66.71% and 63.85% of the variance, respectively. Five factors were significantly associated with physical activity and five significantly associated with time spent outside. Higher correlations were revealed between “general friend support,” “friends’ activity norms,” and physical activity (r=0.343 and 0.333 resp., p<0.001 and between “general friend support” and time spent outside (r=0.460, p<0.001. Obtaining information relating to parental and friends’ influences on physical activity from both parents and children may provide a more complete picture of influences. Parents and friends seem to influence children’s physical activity behavior and time spent outside, but friends’ influences may have a stronger impact on children’s behaviors.

  6. Safety technical investigation activities for shipment of damaged spent fuels from Fukushima Daiichi Nuclear Power Station

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-08-15

    Japan Nuclear Energy Safety Organization(JNES) carries out the investigation for damaged fuel transportation from Fukushima Daiichi Nuclear Power Station(1F) under safety condition to support Nuclear Regulation Authority (NRA). In 2012 fiscal year, JNES carried out the investigation of spent fuel condition in unit 4 of 1F and actual result of leak fuel transport in domestic /other countries. From this result, Package containing damaged fuel from unit 4 in 1F were considered. (author)

  7. A study on the frequency of participation and time spent on sport in different organisational settings

    NARCIS (Netherlands)

    Borgers, J.; Breedveld, K.; Tienen-Raaphorst, A.; Thibaut, E.; Vandermeerschen, H.; Vos, S.B.; Scheerder, J.

    2016-01-01

    Research question: As a result of the expansion of opportunities for leisure-time sport participation (LTSP), the question arises if differing organisational settings relate to differences in participation behaviour. This paper compares participation frequency and time spent on sport between

  8. Time spent in sedentary activities in a pediatric population in Pretoria Central, South Africa.

    Science.gov (United States)

    Goon, Daniel T; Nsibambi, Constance A; Chebet, Milton

    2016-12-01

    Scant information exist on screen time behavior of South Africa children and whether they do not meet the recommendation of American Association of Pediatrics (AAP) concerning screen time activity for children is only speculative. Therefore, the purpose of this study was to examine the time spent in sedentary activities, especially screen time of South African children with regard to gender. This cross-sectional study involved a random sample of 1136 school children (548 boys; 588 girls) aged 9-13 years attending public schools in Central Pretoria, South Africa. Questionnaire was used to collect data on the participants' sedentary behaviors. The prevalence estimates for sedentary time activity was based on the guidelines (i.e., <2 or ≥2 hours per day) of AAP. The mean age of the children was 11.1±1.4 years. Sedentary activity data were collected from 548 boys (48.2%) and 588 (51.8%) girls. The majority of children spent more than two hours per day (exceeding the AAP recommendation for sedentary activity) watching TV (3.0%), worked or played on the computer (25.4%), read (1.0%), played music (27.9%), played board games (14.7%), washing clothes (8.0%), floor sweeping (10.5%), art work (18.2%), and spent time on other unspecified activities (28.6%). Boys spent more time (2 hours, 3-4 hours) watching TV (38.3%; P=0.001), playing computer (31.8 %; P=0.024) and board games (17.4%; P=0.012) than girls. The corresponding figures for girls were 35.7%, 19.2% and 12.5% for TV, computer and board games, respectively. However, the proportion of those who spent more time playing music was higher among girls (32.7%) than boys (22.4%) (P=0.002). Overall, the time spent exceeding AAP recommendation (≥ 2 hours) was not statistically (P=0.427) different between boys and girls. The time spent in sedentary activities, particularly in screen time activity among urban primary school children in Pretoria Central is excessively higher than the recommendation (i.e., ≥2 hours per day

  9. Associations between Parental and Friend Social Support and Children’s Physical Activity and Time Spent outside Playing

    OpenAIRE

    Constantinos A. Loucaides; Niki Tsangaridou

    2017-01-01

    The purpose of this study was to examine the structural validity of a parent and a child questionnaire that assessed parental and friends' influences on children's physical activity and investigate the associations between the derived factors, physical activity, and time spent outside. Children (N = 154, mean age = 11.7) and 144 of their parents completed questionnaires assessing parental and friends' influences on children's physical activity. Children wore a pedometer for six days. Explorat...

  10. Time Spent With Children and Working Parents’ Willingness to Medicate ADHD-Like Behaviors

    Directory of Open Access Journals (Sweden)

    Bora Pajo

    2013-11-01

    Full Text Available How much time parents spend with their children is likely to influence their judgments of children’s behaviors and the behaviors themselves. In the diagnosis of children with attention-deficit/hyperactivity disorder (ADHD, parents are key informants and decide whether their children should receive medication. This exploratory study investigates the relationship between working parents’ willingness to medicate ADHD-like behaviors and the time they can spend with their children during a regular workday. The participants (409 parents of 5- to 17- year-old children reporting having no child with emotional or behavioral problems and 87 reporting having such a child were drawn from a population-based telephone survey of parents stratified by race and ethnicity in two urban Florida counties. Path analysis models, controlling for selected sociodemographic and household variables, showed that spending more time with one’s children during a regular workday and self-identifying as African American were negatively related to willingness to medicate among parents of children with problems. Among parents reporting no children with problems, only the number of children in the household and the parent-type household showed relationships to willingness to medicate, while mothers were more likely than fathers to spend more time with children. These observed relationships were of moderate effect but underscore the importance to initiate studies using valid measures of quantity and quality of parental time spent with ADHD children, and to query parents on these points when assessing the information they provide to clinicians.

  11. The independent relationship between trouble controlling Facebook use, time spent on the site and distress.

    Science.gov (United States)

    Muench, Fredrick; Hayes, Marie; Kuerbis, Alexis; Shao, Sijing

    2015-09-01

    There is an emerging literature base on the relationship between maladaptive traits and "addiction" to social networking sites. These studies have operationalized addiction as either spending excessive amounts of time on social networking sites (SNS) or trouble controlling SNS use, but have not assessed the unique contribution of each of these constructs on outcomes in the same models. Moreover, these studies have exclusively been conducted with younger people rather than a heterogeneous sample. This study examined the independent relationship of a brief Facebook addiction scale, time spent on Facebook, and Facebook checking on positive and negative social domains, while controlling for self-esteem and social desirability. Participants were recruited using e-mail, SNS posts and through Amazon's MTurk system. The sample included 489 respondents ages from 18 to approximately 70, who completed a 10-15 minute survey. Results indicate that neither time spent on Facebook nor Facebook checking was significantly associated with either self-esteem, fear of negative social evaluation or social comparison, while SNS addiction symptoms were each independently associated with Facebook usage. Neither time spent on Facebook nor SNS addiction symptoms were associated with positive social relationships. Overall results suggest that time on SNS and trouble controlling use should be considered independent constructs and that interventions should target underlying loss of control as the primary intervention target above ego syntonic time spent on the site.

  12. The independent relationship between trouble controlling Facebook use, time spent on the site and distress

    Science.gov (United States)

    Muench, Fredrick; Hayes, Marie; Kuerbis, Alexis; Shao, Sijing

    2015-01-01

    Background and Aims There is an emerging literature base on the relationship between maladaptive traits and “addiction” to social networking sites. These studies have operationalized addiction as either spending excessive amounts of time on social networking sites (SNS) or trouble controlling SNS use, but have not assessed the unique contribution of each of these constructs on outcomes in the same models. Moreover, these studies have exclusively been conducted with younger people rather than a heterogeneous sample. This study examined the independent relationship of a brief Facebook addiction scale, time spent on Facebook, and Facebook checking on positive and negative social domains, while controlling for self-esteem and social desirability. Methods Participants were recruited using e-mail, SNS posts and through Amazon’s MTurk system. The sample included 489 respondents ages from 18 to approximately 70, who completed a 10–15 minute survey. Results Results indicate that neither time spent on Facebook nor Facebook checking was significantly associated with either self-esteem, fear of negative social evaluation or social comparison, while SNS addiction symptoms were each independently associated with Facebook usage. Neither time spent on Facebook nor SNS addiction symptoms were associated with positive social relationships. Discussion Overall results suggest that time on SNS and trouble controlling use should be considered independent constructs and that interventions should target underlying loss of control as the primary intervention target above ego syntonic time spent on the site. PMID:26551906

  13. Investigation of the selected properties of dusts from the reclamation of spent sands with bentonite

    Directory of Open Access Journals (Sweden)

    J. Kamińska

    2011-10-01

    Full Text Available The investigation results of the selected properties of dusts generated during the mechanical reclamation of spent sands with bentonite as well as dusts from the dedusting system of sand processing plant are presented in the hereby paper. Investigations were performed with regard to determination conditions allowing to pelletise dusts in the bowl granulator. The verified methods of testing physical and chemical dust properties such as: specific density, bulk density of loosely put materials and apparent density of compacted materials together with their corresponding porosity, ignition losses and pH values, were applied. Granular composition of dusts generated during abrasion of spent binding materials in mechanical dry reclamation processes of spent sands with bentonite and coal dusts were performed by the laser diffraction analysis, allowing to broaden the measuring range of particle diameters. The optimal wetting agent content (in this case water at which the dust-water mixture obtains the best strength properties – after compacting by means of the standard moulder’s rammer – was determined.

  14. Parent Perceptions of Time Spent Meaningfully by Young Adults with Pervasive Support Needs

    Science.gov (United States)

    Rossetti, Zachary; Lehr, Donna; Lederer, Leslie; Pelerin, Dana; Huang, Shuoxi

    2015-01-01

    This article describes a qualitative study that examined how 23 young adults with pervasive support needs and limited functional communication spent their time and how their parents (n = 23) and direct support professionals (DSPs; n = 2) defined meaningfulness in relation to the young adults' experiences. Data were collected through…

  15. Evaluation of daily time spent in transportation and traffic-influenced microenvironments by urban Canadians.

    Science.gov (United States)

    Matz, Carlyn J; Stieb, David M; Egyed, Marika; Brion, Orly; Johnson, Markey

    2018-01-01

    Exposure to traffic and traffic-related air pollution is associated with a wide array of health effects. Time spent in a vehicle, in active transportation, along roadsides, and in close proximity to traffic can substantially contribute to daily exposure to air pollutants. For this study, we evaluated daily time spent in transportation and traffic-influenced microenvironments by urban Canadians using the Canadian Human Activity Pattern Survey (CHAPS) 2 results. Approximately 4-7% of daily time was spent in on- or near-road locations, mainly associated with being in a vehicle and smaller contributions from active transportation. Indoor microenvironments can be impacted by traffic emissions, especially when located near major roadways. Over 60% of the target population reported living within one block of a roadway with moderate to heavy traffic, which was variable with income level and city, and confirmed based on elevated NO 2 exposure estimated using land use regression. Furthermore, over 55% of the target population ≤ 18 years reported attending a school or daycare in close proximity to moderate to heavy traffic, and little variation was observed based on income or city. The results underline the importance of traffic emissions as a major source of exposure in Canadian urban centers, given the time spent in traffic-influenced microenvironments.

  16. Re-Examining Gender Differences in Video Game Play: Time Spent and Feelings of Success

    Science.gov (United States)

    Hamlen, Karla R.

    2010-01-01

    Research has shown that, among children, boys tend to play video games more than girls do. There are several theories addressing this phenomenon, including that stereotypes and lack of opportunity leave girls feeling inadequate with certain types of technology. No research has yet examined the interactive relationships between time spent playing…

  17. Heart rate biofeedback fails to enhance children's ability to identify time spent in moderate to vigorous physical activity.

    Science.gov (United States)

    Conley, Marguerite M; Gastin, Paul B; Brown, Helen; Shaw, Christine

    2011-03-01

    Physical activity recommendations for children in several countries advise that all young people should accumulate at least 60 min of moderate to vigorous physical activity every day. Perceiving physical activity intensity, however, can be a difficult task for children and it is not clear whether children can identify their levels of moderate to vigorous physical activity in accordance with the recommended guidelines. This study aimed to (1) explore whether children can identify time spent in moderate to vigorous physical activity; and (2) investigate whether heart rate biofeedback would improve children's ability to estimate time spent in moderate to vigorous physical activity. Thirty seven children (15 boys and 22 girls, mean age 12.6 years) wore data recording Polar E600 heart rate monitors during eight physical education lessons. At the end of each lesson children's estimated time in zone was compared to their actual time in zone. During a six lesson Intervention phase, one class was assigned to a biofeedback group whilst the other class acted as the control group and received no heart rate biofeedback. Post-Intervention, students in the biofeedback group were no better than the control group at estimating time spent in zone (mean relative error of estimation biofeedback group: Pre-Intervention 41±32% to Post-Intervention 28±26%; control group: Pre-Intervention 40±39% to Post-Intervention 31±37%). Thus it seems that identifying time spent in moderate to vigorous physical activity remains a complex task for children aged 11-13 even with the help of heart rate biofeedback. Copyright © 2010 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  18. Time spent with friends in adolescence relates to less neural sensitivity to later peer rejection.

    Science.gov (United States)

    Masten, Carrie L; Telzer, Eva H; Fuligni, Andrew J; Lieberman, Matthew D; Eisenberger, Naomi I

    2012-01-01

    Involvement with friends carries many advantages for adolescents, including protection from the detrimental effects of being rejected by peers. However, little is known about the mechanisms through which friendships may serve their protective role at this age, or the potential benefit of these friendships as adolescents transition to adulthood. As such, this investigation tested whether friend involvement during adolescence related to less neural sensitivity to social threats during young adulthood. Twenty-one adolescents reported the amount of time they spent with friends outside of school using a daily diary. Two years later they underwent an fMRI scan, during which they were ostensibly excluded from an online ball-tossing game by two same-age peers. Findings from region of interest and whole brain analyses revealed that spending more time with friends during adolescence related to less activity in the dorsal anterior cingulate cortex and anterior insula--regions previously linked with negative affect and pain processing--during an experience of peer rejection 2 years later. These findings are consistent with the notion that positive relationships during adolescence may relate to individuals being less sensitive to negative social experiences later on.

  19. Simulation-based Investigation of Electric Power Generation by Using Gamma Radiation from Spent Nuclear Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Haneol; Yim, Mansung [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2014-05-15

    This study investigates the feasibility of using gamma radiation energy from spent nuclear fuels to produce electricity as emergency power source. The proposed electric power system includes electricity generation and storage. Electricity generation was based on conversion of gamma energy to light energy using a scintillator and then to electric energy using a solar cell. Generated electricity was to be stored in a battery as a power source. The efficiency of energy conversion and the extent of the resulting electric power source capability were examined by computer model-based simulation. Main factors which affect to total electric power generated include thermal power of nuclear power plant, average burn-up period for fuel rod, battery charging time, and scintillator thickness. The estimated total power generation and its possible application is discussed. Although the output power increases as scintillator becomes thicker, thick scintillator can be problem because of its high price. There are two ways to solve this problem. The first one is to use thin scintillator to whole fuel assembly area. The second one is to use thick scintillator to limited region. But the current per fuel assembly for the first case for 4000MWth, 72 month burnup is about several to tens of microampere scale, which is too small to charge. Because of this the system is supposed to have thick scintillator system with limited region. Based on the results, the generated electricity is expected to be insufficient to operate the safety injection pumps even at the maximum power output. This may be important for security purposes. Based on the current design, the solar cell efficiency is estimated to be around 1.5-4%. As the efficiency is a strong function of scintillation wavelength, improving the efficiency may be possible by broadening the wavelength through the use of multiple scintillators. Future work will also include validation of the results through experiments, and material reliability

  20. Simulation-based Investigation of Electric Power Generation by Using Gamma Radiation from Spent Nuclear Fuel

    International Nuclear Information System (INIS)

    Lee, Haneol; Yim, Mansung

    2014-01-01

    This study investigates the feasibility of using gamma radiation energy from spent nuclear fuels to produce electricity as emergency power source. The proposed electric power system includes electricity generation and storage. Electricity generation was based on conversion of gamma energy to light energy using a scintillator and then to electric energy using a solar cell. Generated electricity was to be stored in a battery as a power source. The efficiency of energy conversion and the extent of the resulting electric power source capability were examined by computer model-based simulation. Main factors which affect to total electric power generated include thermal power of nuclear power plant, average burn-up period for fuel rod, battery charging time, and scintillator thickness. The estimated total power generation and its possible application is discussed. Although the output power increases as scintillator becomes thicker, thick scintillator can be problem because of its high price. There are two ways to solve this problem. The first one is to use thin scintillator to whole fuel assembly area. The second one is to use thick scintillator to limited region. But the current per fuel assembly for the first case for 4000MWth, 72 month burnup is about several to tens of microampere scale, which is too small to charge. Because of this the system is supposed to have thick scintillator system with limited region. Based on the results, the generated electricity is expected to be insufficient to operate the safety injection pumps even at the maximum power output. This may be important for security purposes. Based on the current design, the solar cell efficiency is estimated to be around 1.5-4%. As the efficiency is a strong function of scintillation wavelength, improving the efficiency may be possible by broadening the wavelength through the use of multiple scintillators. Future work will also include validation of the results through experiments, and material reliability

  1. Investigating the potential of thermophilic species for ethanol production from industrial spent sulfite liquor

    Directory of Open Access Journals (Sweden)

    Michaela Weissgram

    2015-10-01

    Full Text Available Thermophilic microorganisms hold a great potential for bioethanol production on waste biomass, due to their ability to utilize pentoses and hexoses alike. However, to date hardly any data on thermophiles growing directly on industrial substrates like spent sulfite liquor (SSL are available. This contribution investigates the ability of Thermoanaerobacter species to utilize the main sugars in the used SSL (mannose, glucose and xylose and the effect of process parameters (pH, temperature and sugar concentration on their growth. Based on these results the strain T. mathranii was chosen for further studies. The ability of T. mathranii to grow directly on SSL was investigated and the effect of several inhibiting substances on growth was elucidated. Furthermore it was tested whether pretreatment with activated charcoal can increase the fermentability of SSL. The fermentations were evaluated based on yields and specific rates. It could be shown that T. mathranii was able to ferment all sugars in the investigated softwood SSL and fermented diluted, untreated SSL (up to 2.7% (w/w dry matter. Pretreatment with activated charcoal could slightly reduce the amount of phenols in the substrate and thus facilitate growth and ethanol production on higher SSL concentrations (up to 4.7% (w/v dry matter. Ethanol yields of 0.29-0.44 Cmmol of ethanol per Cmmol sugar were obtained on untreated and pretreated spent sulfite liquor, respectively. These results on an industrial substrate strengthen the claim that thermophilic microorganisms might be the optimal candidates for forest biorefinery.

  2. Some notes on the Timing of Geological Disposal of CANDU Spent Fuels

    International Nuclear Information System (INIS)

    Choi, Heui Joo; Kook, Dong Hak; Choi, Jong Won

    2010-01-01

    CANDU spent fuel is to be disposed of at repository finally rather than recycled because of its low fissile nuclide concentration. But the difficult situation of finding a repository site can not help introducing a interim storage in the short term. It is required to find an optimum timing of geological disposal of CANDU spent fuels related to the interim storage operation period. The major factors for determining the disposal starting time are considered as safety, economics, and public acceptance. Safety factor is compared in terms of the decay heat and non-proliferation. Economics factor is compared from the point of the operation cost, and public acceptance factor is reviewed from the point of retrievability and inter-generation ethics. This paper recommended the best solution for the disposal starting time by analyzing the above factors. It is concluded that the optimum timing for the CANDU spent fuel disposal is around 2041 and that the sooner disposal time, the better from the point of technical and safety aspects.

  3. Eye movements discriminate fatigue due to chronotypical factors and time spent on task--a double dissociation.

    Directory of Open Access Journals (Sweden)

    Dario Cazzoli

    Full Text Available Systematic differences in circadian rhythmicity are thought to be a substantial factor determining inter-individual differences in fatigue and cognitive performance. The synchronicity effect (when time of testing coincides with the respective circadian peak period seems to play an important role. Eye movements have been shown to be a reliable indicator of fatigue due to sleep deprivation or time spent on cognitive tasks. However, eye movements have not been used so far to investigate the circadian synchronicity effect and the resulting differences in fatigue. The aim of the present study was to assess how different oculomotor parameters in a free visual exploration task are influenced by: a fatigue due to chronotypical factors (being a 'morning type' or an 'evening type'; b fatigue due to the time spent on task. Eighteen healthy participants performed a free visual exploration task of naturalistic pictures while their eye movements were recorded. The task was performed twice, once at their optimal and once at their non-optimal time of the day. Moreover, participants rated their subjective fatigue. The non-optimal time of the day triggered a significant and stable increase in the mean visual fixation duration during the free visual exploration task for both chronotypes. The increase in the mean visual fixation duration correlated with the difference in subjectively perceived fatigue at optimal and non-optimal times of the day. Conversely, the mean saccadic speed significantly and progressively decreased throughout the duration of the task, but was not influenced by the optimal or non-optimal time of the day for both chronotypes. The results suggest that different oculomotor parameters are discriminative for fatigue due to different sources. A decrease in saccadic speed seems to reflect fatigue due to time spent on task, whereas an increase in mean fixation duration a lack of synchronicity between chronotype and time of the day.

  4. Maternal Time Use and Nurturing: Analysis of the Association Between Breastfeeding Practice and Time Spent Interacting with Baby.

    Science.gov (United States)

    Smith, Julie P; Forrester, Robert

    2017-06-01

    Breastfeeding supports child development through complex mechanisms that are not well understood. Numerous studies have compared how well breastfeeding and nonbreastfeeding mothers interact with their child, but few examine how much interaction occurs. Our study of weekly time use among 156 mothers of infants aged 3-9 months investigated whether lactating mothers spend more time providing emotional support or cognitive stimulation of their infants than nonbreastfeeding mothers, and whether the amount of such interactive time is associated with breastfeeding intensity. Mothers were recruited via mother's and baby groups, infant health clinics, and childcare services, and used an electronic device to record their 24-hour time use for 7 days. Sociodemographic and feeding status data were collected by questionnaire. Statistical analysis using linear mixed modeling and residual maximum likelihood analysis compared maternal time use for those giving "some breastfeeding" and those "not breastfeeding." Analysis was also conducted for more detailed feeding subgroups. Breastfeeding and nonbreastfeeding mothers had broadly similar socioeconomic and demographic characteristics. Breastfeeding was found to be associated with more mother-child interaction time, a difference only partially explained by weekly maternal employment hours or other interactive care activities such as play or reading. This study presents data suggesting that lactating mothers spent significantly more hours weekly on milk feeding and on carrying, holding, or soothing their infant than nonlactating mothers; and on providing childcare. Understanding the mechanisms by which child mental health and development benefits from breastfeeding may have important implications for policies and intervention strategies, and could be usefully informed by suitably designed time use studies.

  5. Investigation of fission products release and structural changes of WWER spent fuel in inert and oxidizing environment

    International Nuclear Information System (INIS)

    Kungurtsev, I.A.; Smirnov, V.P.; Kuzmin, I.V.; Lebeduk, I.V.; Pimonov, Y.I.; Sohcilin, G.I.; Stupina, L.N.; Chesanov, V.V.; Shtuckert, Y.A.; Zvir, E.A.

    1996-01-01

    At the Research Institute of Atomic Reactors in-cell experiments were carried out which were aimed at investigation of WWER spent fuel behaviour under accident conditions. Gaseous and volatile fission products release and the influence of gaseous swelling, fuel interaction with the cladding and oxidation on it have been investigated. At the present time, series of experiments in inert and air environments have been finished and the tests in steam environment have been carrying out. In all series the samples in the form of fuel pellets fragments and fuel elements pieces were used. This report presents some results of annealing tests and investigations of the sample microstructure after annealing. (author). 4 refs, 15 figs, 2 tabs

  6. Investigation of Electricity Generation by Using Gamma Radiation from Spent Fuels

    International Nuclear Information System (INIS)

    Lee, Haneol; Yim, Man-Sung Yim

    2015-01-01

    The purpose of this study is to investigate the electric power generation with scale spent fuel. OrigenArp has analyzed gamma radiation environment of spent fuel assembly, MCNPX has analyzed the scintillator behavior, and experimental work has analyzed the electric output of photovoltaic cell. Gamma radiation environment analysis result indicates gamma source rapidly decreases for the early storage period. Scintillator analysis result calculates the photon flux distribution which enters photovoltaic cell. Photovoltaic cell experiment calculates electric current, voltage current generation per each system unit. Generated electric power can be used to cope with existing safety system (i.e. storage monitoring system) under severe accident or to operate security system under external invasion situation (i.e. passive physical barrier system). Several researchers have shown that converting radiation energy into electric energy is possible. Karl Scharf studied the direct electric conversion of radiation energy by using photovoltaic cells. Researchers in University of Massachusetts Lowell have studied radiation-electric energy conversion by using gadolinium oxide scintillator and dye sensitized solar cell (DSSCs) and N. Horuichi et al. studied radiation-electric energy conversion by using inorganic scintillators and amorphous and crystal photovoltaic cells

  7. Time Spent by Calliphora Spp. Blowflies on Standard Traps Baited with Liver and Ammonia

    Directory of Open Access Journals (Sweden)

    Florica Morariu

    2010-10-01

    Full Text Available The larvae of blowflies from the Calliphoridae family cause fly strikes in sheep and other species of economic importance. Impaired wool, decrease of ewe fertility, and even death can occur in heavy infestations. This paper describes the Calliphora spp. blowflies’ behavior on and around a trap baited with liver and ammonia before they entered in. More than half of Calliphora spp. blowflies (50.88% stayed a medium time (eight to fourteen seconds on the standard trap, while only 1.79% of them spent a longer time (26 to 30 seconds before entering the trap.

  8. Experimental Investigation of Burnup Credit for Safe Transport, Storage, and Disposal of Spent Nuclear Fuel

    International Nuclear Information System (INIS)

    Harms, Gary A.; Helmick, Paul H.; Ford, John T.; Walker, Sharon A.; Berry, Donald T.; Pickard, Paul S.

    2004-01-01

    This report describes criticality benchmark experiments containing rhodium that were conducted as part of a Department of Energy Nuclear Energy Research Initiative project. Rhodium is an important fission product absorber. A capability to perform critical experiments with low-enriched uranium fuel was established as part of the project. Ten critical experiments, some containing rhodium and others without, were conducted. The experiments were performed in such a way that the effects of the rhodium could be accurately isolated. The use of the experimental results to test neutronics codes is demonstrated by example for two Monte Carlo codes. These comparisons indicate that the codes predict the behavior of the rhodium in the critical systems within the experimental uncertainties. The results from this project, coupled with the results of follow-on experiments that investigate other fission products, can be used to quantify and reduce the conservatism of spent nuclear fuel safety analyses while still providing the necessary level of safety

  9. Results from Nevada Nuclear Waste Storage Investigations (NNWSI) Series 3 spent fuel dissolution tests

    International Nuclear Information System (INIS)

    Wilson, C.N.

    1990-06-01

    The dissolution and radionuclide release behavior of spent fuel in groundwater is being studied by the Yucca Mountain Project (YMP), formerly the Nevada Nuclear Waste Storage Investigations (NNWSI) Project. Specimens prepared from pressurized water reactor fuel rod segments were tested in sealed stainless steel vessels in Nevada Test Site J-13 well water at 85 degree C and 25 degree C. The test matrix included three specimens of bare-fuel particles plus cladding hulls, two fuel rod segments with artificially defected cladding and water-tight end fittings, and an undefected fuel rod section with watertight end fittings. Periodic solution samples were taken during test cycles with the sample volumes replenished with fresh J-13 water. Test cycles were periodically terminated and the specimens restarted in fresh J-13 water. The specimens were run for three cycles for a total test duration of 15 months. 22 refs., 32 figs., 26 tabs

  10. Investigation of nuclide importance to functional requirements related to transport and long-term storage of LWR spent fuel

    International Nuclear Information System (INIS)

    Broadhead, B.L.; DeHart, M.D.; Ryman, J.C.; Tang, J.S.; Parks, C.V.

    1995-06-01

    This study investigates the relative importances of the various actinide, fission-product, and light-element isotopes associated with LWR spent fuel with respect to five analysis areas: criticality safety (absorption fractions), shielding (dose rate fractions), curies (fractional curies levels), decay heat (fraction of total watts), and radiological toxicity (fraction of potential committed effective dose equivalent). These rankings are presented for up to six different burnup/enrichment scenarios and at decay times from 2 to 100,000 years. Ranking plots for each of these analysis areas are given in an Appendix for completeness, as well as summary tables in the main body of the report. Summary rankings are presented in terms of high (greater than 10% contribution to the total), medium (between 1% and 10% contribution), and low (less than 1% contribution) for both short- and long-term cooling. When compared with the expected measurement accuracies, these rankings show that most of the important isotopes can be characterized sufficiently for the purpose of radionuclide generation/depletion code validation in each of the analysis areas. Because the main focus of this work is on the relative importances of isotopes associated with L at sign spent fuel, some conclusions may not be applicable to similar areas such as high-level waste (HLW) and nonfuel-bearing components (NFBC)

  11. Investigation of Nuclide Importance to Functional Requirements Related to Transport and Long-Term Storage of LWR Spent Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Broadhead, B.L.

    1995-01-01

    The radionuclide characteristics of light-water-reactor (LWR) spent fuel play key roles in the design and licensing activities for radioactive waste transportation systems, interim storage facilities, and the final repository site. Several areas of analysis require detailed information concerning the time-dependent behavior of radioactive nuclides including (1) neutron/gamma-ray sources for shielding studies, (2) fissile/absorber concentrations for criticality safety determinations, (3) residual decay heat predictions for thermal considerations, and (4) curie and/or radiological toxicity levels for materials assumed to be released into the ground/environment after long periods of time. The crucial nature of the radionuclide predictions over both short and long periods of time has resulted in an increased emphasis on thorough validation for radionuclide generation/depletion codes. Current radionuclide generation/depletion codes have the capability to follow the evolution of some 1600 isotopes during both irradiation and decay time periods. Of these, typically only 10 to 20 nuclides dominate contributions to each analysis area. Thus a quantitative ranking of nuclides over various time periods is desired for each of the analysis areas of shielding, criticality, heat transfer, and environmental dose (radiological toxicity). These rankings should allow for validation and data improvement efforts to be focused only on the most important nuclides. This study investigates the relative importances of the various actinide, fission-product, and light-element isotopes associated with LWR spent fuel with respect to five analysis areas: criticality safety (absorption fractions), shielding (dose rate fractions), curies (fractional curies levels), decay heat (fraction of total watts), and radiological toxicity (fraction of potential committed effective dose equivalent). These rankings are presented for up to six different burnup/enrichment scenarios and at decay times from 2 to

  12. Psychological, interpersonal, and clinical factors predicting time spent on physical activity among Mexican patients with hypertension.

    Science.gov (United States)

    Ybarra Sagarduy, José Luis; Camacho Mata, Dacia Yurima; Moral de la Rubia, José; Piña López, Julio Alfonso; Yunes Zárraga, José Luis Masud

    2018-01-01

    It is widely known that physical activity is the key to the optimal management and clinical control of hypertension. This research was conducted to identify factors that can predict the time spent on physical activity among Mexican adults with hypertension. This cross-sectional study was conducted among 182 Mexican patients with hypertension, who completed a set of self-administered questionnaires related to personality, social support, and medical adherence and health care behaviors, body mass index, and time since the disease diagnosis. Several path analyses were performed in order to test the predictors of the study behavior. Lower tolerance to frustration, more tolerance to ambiguity, more effective social support, and less time since the disease diagnosis predicted more time spent on physical activity, accounting for 13.3% of the total variance. The final model shows a good fit to the sample data ( p BS =0.235, χ 2 / gl =1.519, Jöreskog and Sörbom's Goodness of Fit Index =0.987, adjusted modality =0.962, Bollen's Incremental Fit Index =0.981, Bentler-Bonett Normed Fit Index =0.946, standardized root mean square residual =0.053). The performance of physical activity in patients with hypertension depends on a complex set of interactions between personal, interpersonal, and clinical variables. Understanding how these factors interact might enhance the design of interdisciplinary intervention programs so that quality of life of patients with hypertension improves and they might be able to manage and control their disease well.

  13. Physical activity and time spent sitting as a risk factor for low-back pain: longitudinal data from the HUNT study

    OpenAIRE

    Venseth, Torje Bragstad

    2014-01-01

    Background: Low back pain (LBP) is the most common pain condition with a lifetime prevalence of 70 %. One of the most investigated risk factor for LBP is sedentary lifestyle. This is of great interest as sitting is the more dominant occupational activity in today’s society. Aim: The aim of this study was to prospectively investigate if the risk of chronic LBP is associated with time spent sitting, leisure time physical activity, and occupational activity. We also examined the combined eff...

  14. Direct Investigations of the Immobilization of Radionuclides in the Alteration Products of Spent Nuclear Fuel

    International Nuclear Information System (INIS)

    Burns, Peter C.; Finch, Robert J.; Wronkiewicz, David J.

    2004-01-01

    Safe disposal of the nation's nuclear waste in a geological repository involves unique scientific and engineering challenges owing to the very long-lived radioactivity of the waste. The repository must retain a variety of radionuclides that have vastly different chemical characters for several thousand years. Most of the radioactivity that will be housed in the proposed repository at Yucca Mountain will be associated with spent nuclear fuel, much of which is derived from commercial reactors. DOE is custodian of approximately 8000 tons of spent nuclear fuel that is also intended for eventual disposal in a geological repository. Unlike the spent fuel from commercial reactors, the DOE fuel is diverse in composition with more than 250 varieties. Safe disposal of spent fuel requires a detailed knowledge of its long-term behavior under repository conditions, as well as the fate of radionuclides released from the spent fuel as waste containers are breached

  15. How do passion for video games and needs frustration explain time spent gaming?

    Science.gov (United States)

    Mills, Devin J; Milyavskaya, Marina; Mettler, Jessica; Heath, Nancy L; Derevensky, Jeffrey L

    2018-04-01

    Research applying self-determination theory and the dualistic model of passion (DMP) has shown video games may satisfy basic psychological needs (i.e., competence, autonomy, and relatedness) and be identified as a passion. The DMP distinguishes between healthy or harmonious passion and problematic or obsessive passion (OP), with the latter reflecting an overreliance towards one's passion to obtain needs satisfaction. The experience of daily obstructions to needs satisfaction, or needs frustration (NF), may facilitate such an overreliance. This study explored how NF and both types of passion explain the amount of time that university students spend gaming. The overall association between NF and time spent gaming was not significant. However, for video game users with low levels of OP for gaming, there was a significant negative association between NF and time spent gaming. Additionally, evidence of a mutually reinforcing association between NF and OP for gaming indicates that a vicious cycle exists, whereby a strong OP for gaming predicts and is reinforced by greater NF. The theoretical implications are discussed. © 2018 The British Psychological Society.

  16. Drilling of deep boreholes and associated geological investigations. Final disposal of spent fuel

    International Nuclear Information System (INIS)

    Anttila, P.

    1983-12-01

    Teollisuuden Voima Oy (Industrial Power Company Ltd.) will take precautions for the final disposal of spent fuel in the Finnish bedrock. The first stage of the site selection studies includes drilling of a deep borehole down to approximately 1000 metres in the winter of 1984. The choice of drilling method and equipment depends on the geological circumstances and the target of the investigation. The most common drilling methods used with the investigations of nuclear waste disposal are diamond core drilling and percussion drilling. The Precambrian bedrock outcropping in Finland exists also in Sweden and Canada, where deep boreholes have been done down to more than 1000 metres using diamond core drilling. This method can be also used in Finland and equipment for the drilling are available. One of the main targets of the investigation is to clarify the true strike and dip of fractures and other discontinuities. The methods used abroad are taking of oriented cores, borehole television survey and geophysical measurements. TV-survey and geophysical methods seem to be most favourable in deep boreholes. Also the accurate position (inclination, bearing) of the borehole is essential to know and many techniques are used for measuring of it. Investigations performed on the core samples include core logging and laboratory tests. For the core logging there is no uniform practice concerning the nuclear waste investigations. Different counries use their own classifications. All of these, however, are based on the petrography and fracture properties of the rock samples. Laboratory tests (petrographical and rock mechanical tests) are generally performed according to the recommendations of international standards. The large volumes of data obtained during investigations require computer techniques which allow more comprehensive collection, storage and processing of data. This kind of systems are already used in Sweden and Canada, for instance, and they could be utilize in Finland

  17. Associations between maternal employment and time spent in nutrition-related behaviours among German children and mothers.

    Science.gov (United States)

    Möser, Anke; Chen, Susan E; Jilcott, Stephanie B; Nayga, Rodolfo M

    2012-07-01

    To examine associations between maternal employment and time spent engaging in nutrition-related behaviours among mothers and children using a nationally representative sample of households in West and East Germany. A cross-sectional analysis was performed using time-use data for a sample of mother-child dyads. Associations between maternal employment and time spent in nutrition-related activities such as eating at home, eating away from home and food preparation were estimated using a double-hurdle model. German Time Budget Survey 2001/02. The overall sample included 1071 households with a child between 10 and 17 years of age. The time-use data were collected for a 3 d period of observation (two weekdays and one weekend day). Maternal employment was associated with the time children spent on nutrition-related behaviours. In households with employed mothers, children spent more time eating alone at home and less time eating meals with their mothers. Moreover, employed mothers spent less time on meal preparation compared with non-employed mothers. There were regional differences in time spent on nutrition-related behaviours, such that East German children were more likely to eat at home alone than West German children. Maternal employment was associated with less time spent eating with children and preparing food, which may be related to the increasing childhood obesity rates in Germany. Future national surveys that collect both time-use data and health outcomes could yield further insight into mechanisms by which maternal time use might be associated with health outcomes among children.

  18. Automated methods for real-time analysis of spent-fuel measurement data

    International Nuclear Information System (INIS)

    Bosler, G.E.; Rinard, P.M.; Klosterbuer, S.F.; Painter, J.

    1988-01-01

    Software has been developed for ''real-time'' analysis of neutron and gamma data from GRAND-1/fork measurements on spent-fuel assemblies. Three modules compose the software package. The modules are linked through a database system of files. The first module is part of a general data-base processing code. This module prepares input data files with inventory and correction-factor information for the second module. The second module, called OLAF, operates on a computer attached to the GRAND-1 electronics unit. In this second module, neutron and gamma data from spent-fuel assemblies are analyzed to verify consistency in the facility operator declarations for exposure (burnup) and cooling time. From the analysis, potential discrepancies in the measurement data are questioned while equipment is still installed at the facility and is available for additional measurements. During the measurements, data are written to an output file, called a results file, which can be processed by the third module of the software package. In the third module, printed reports summarizing the data and results are prepared, and neutron and gamma data are written to files that are process by the Deming curve-fitting code

  19. Time spent sitting during and outside working hours in bus drivers: A pilot study.

    Science.gov (United States)

    Varela-Mato, Veronica; Yates, Thomas; Stensel, David J; Biddle, Stuart J H; Clemes, Stacy A

    2016-06-01

    This cross-sectional pilot study objectively measured sedentary and non-sedentary time in a sample of bus drivers from the East Midlands, United Kingdom. Participants wore an activPAL3 inclinometer for 7 days and completed a daily diary. Driver's blood pressure, heart rate, waist circumference and body composition were measured objectively at the outset. The proportions of time spent sedentary and non-sedentary were calculated during waking hours on workdays and non-workdays and during working-hours and non-working-hours on workdays. 28 (85% of those enrolled into the study) provided valid objective monitoring data (89.3% male, [median ± IQR] age: 45.2 ± 12.8 years, BMI 28.1 ± 5.8 kg/m(2)). A greater proportion of time was spent sitting on workdays than non-workdays (75% [724 ± 112 min/day] vs. 62% [528 ± 151 min/day]; p working-hours than non-working-hours (83% [417 ± 88 min/day] vs. 68% [307 ± 64 min/day]; p less than 3% of their overall time stepping. Bus drivers accumulate high levels of sitting time during working-hours and outside working-hours. Interventions are urgently needed in this at-risk group, which should focus on reducing sitting and increasing movement during breaks and increasing physical activity during leisure time to improve cardiovascular health.

  20. Relationship of Near-Crash/Crash Risk to Time Spent on a Cell Phone While Driving.

    Science.gov (United States)

    Farmer, Charles M; Klauer, Sheila G; McClafferty, Julie A; Guo, Feng

    2015-01-01

    The objective of this study was to examine in a naturalistic driving setting the dose-response relationship between cell phone usage while driving and risk of a crash or near crash. How is the increasing use of cell phones by drivers associated with overall near-crash/crash risk (i.e., during driving times both on and off the phone)? Day-to-day driving behavior of 105 volunteer subjects was monitored over a period of 1 year. A random sample was selected comprised of 4 trips from each month that each driver was in the study, and in-vehicle video was used to classify driver behavior. The proportion of driving time spent using a cell phone was estimated for each 3-month period and correlated with overall crash and near-crash rates for each period. Thus, it was possible to test whether changes in an individual driver's cell phone use over time were associated with changes in overall near-crash/crash risk. Drivers in the study spent 11.7% of their driving time interacting with a cell phone, primarily talking on the phone (6.5%) or simply holding the phone in their hand or lap (3.7%). The risk of a near-crash/crash event was approximately 17% higher when the driver was interacting with a cell phone, due primarily to actions of reaching for/answering/dialing, which nearly triples risk (relative risk = 2.84). However, the amount of driving time spent interacting with a cell phone did not affect a driver's overall near-crash/crash risk. Vehicle speeds within 6 s of the beginning of each call on average were 5-6 mph lower than speeds at other times. Results of this naturalistic driving study are consistent with the observation that increasing cell phone use in the general driving population has not led to increased crash rates. Although cell phone use can be distracting and crashes have occurred during this distraction, overall crash rates appear unaffected by changes in the rate of cell phone use, even for individual drivers. Drivers compensate somewhat for the distraction

  1. Determination of burnup, cooling time and initial enrichment of PWR spent fuel by use of gamma-ray activity ratios

    International Nuclear Information System (INIS)

    Min, D.K.; Park, H.J.; Park, K.J.; Ro, S.G.; Park, H.S.

    1999-01-01

    The Korea Atomic Energy Institute has been developing the algorithms for sequential determination of cooling time, initial enrichment and burnup of the PWR spent fuel assembly by use of gamma ratio measurements, i.e. 134 Cs/ 137 Cs, 154 Eu/ 137 Cs and 106 Ru 137 Cs/( 134 Cs) 2 . Calculations were performed by applying the ORIGEN-S code. This method has advantages over combination techniques of neutron and gamma measurement, because of its simplicity and insensitivity to the measurement geometry. For verifying the algorithms an experiment for determining the cooling time, initial enrichment and burnup of the two PWR spent fuel rods was conducted by use of high-resolution gamma detector (HPGe) system only. This paper describes the method used and interim results of the experiment. This method can be applied for spent fuel characterization, burnup credit and safeguards of the spent fuel management facility

  2. Investigation on the status of rare earth elements contained in the powder of spent fluorescent lamps

    International Nuclear Information System (INIS)

    Belardi, G.; Ippolito, N.; Piga, L.; Serracino, M.

    2014-01-01

    Highlights: • Most of rare earth elements are contained in particles of size finer than 7 μm. • Most of Si, K and Na are contained in the coarser size-fractions. • The phases in the size-fractions of the fluorescent powder have been determined. • Europium is contained in yttrium oxide and in vanadium–yttrium oxides. • The crystallo–chemical composition of all the phases has been determined. - Abstract: The aim of this study is to examine the status of rare earth elements (REE) contained in the chemical compounds that make up the powder of spent fluorescent lamps, with a view of their recovery. The status of REE in the as-received powder, as well as in a few size-class fractions of it, has been established. This way, only those size-class fractions containing high REE concentrations can be considered in a recovery process. The investigation has been carried out using particle-size, chemical, TGA/DTA, XRPD, SEM-EDS and EMPA analyses. The last technique enabled to establish the status of REE within the lattice of the chemical compounds present in the powder. The fineness of the as-received powder and the higher REE concentration in the finest size-classes suggest that physical methods of separation should not be used to separate the REE-containing chemical compounds from each other. Leaching methods seem more suitable with a material of such size

  3. Investigation on structural analysis computer program of spent nuclear fuel shipping cask, (2)

    International Nuclear Information System (INIS)

    Yagawa, Ganki; Ikushima, Takeshi.

    1987-10-01

    This report describes the results (II) done by the Sub-Committee of Research Cooperation Committee (RC-62) of the Japan Society of Mechanical Engineers under the trust of the Japan Atomic Energy Research Institute. The principal fulfilments and accomplishments are summarized as follows: (1) Regarding the survey of structural analysis methods of spent fuel shipping cask, several documents, which explain the features and applications of the exclusive computer programs for impact analysis on the basis of 2 or 3 dimensional finite element or difference methods, were reviewed. (2) In comparative evaluation of the existing computer programs, the common benchmark test problems for drop impact of the axisymmetric cylinder and plate were adopted the calculational evaluations for taking into account the strain rate effect of material properties, effect of artificial viscosity and effect of time integration step size were carried out. (3) Evaluation of impact analysis algorithm of computer programs were conducted and the requirements for computer programs to be developed in future and an index for further studies have been clarified. (author)

  4. Effect of the time spent by the photon in the absorbed state on the time-dependent transfer of radiation

    International Nuclear Information System (INIS)

    Rao, D.M.; Rangarajan, K.E.; Peraiah, A.

    1990-01-01

    The time-dependent transfer equation is derived for a two-level atomic model which takes both bound-bound and bound-free transitions into account. A numerical scheme is proposed for solving the monochromatic time-dependent transfer equation when the time spent by the photon in the absorbed state is significant. The method can be easily extended to solve the problem of time-dependent line formation of the bound-free continuum. It is used here to study three types of boundary conditions of the incident radiation incident on a scattering atmosphere. The quantitative results show that the relaxation of the radiation field depends on the optical depth of the medium and on the ray's angle of emergence. 21 refs

  5. Investigations of physicochemical properties of dusts generated in mechanical reclamation process of spent moulding sands with alkaline resins

    Directory of Open Access Journals (Sweden)

    R. Dańko

    2014-03-01

    Full Text Available Mechanical reclamation processes of spent moulding sands generate large amounts of post-reclamation dusts mainly containing rubbed spent binding agents and quartz dusts. The amount of post-reclamation dusts, depending in the reclamation system efficiency and the reclaim dedusting system, can reach 5%-10% in relation to the total reclaimed spent moulding sand. The proper utilization of such material is a big problem facing foundries these days. This study presents the results of investigations of physicochemical properties of post- reclamation dusts. All tested dusts originated from various Polish cast steel plants applying the mechanical reclamation process of moulding sands with alkaline resins, obtained from different producers. Different dusts, delivered from foundries, were tested to determine their chemical composition, granular characterization, physicochemical and energetic properties. Presented results confirmed assumptions that it is possible to utilize dusts generated during mechanical reclamation of used sands with organic resins as a source of energy.

  6. Overweight according to geographical origin and time spent in France: a cross sectional study in the Paris metropolitan area

    Directory of Open Access Journals (Sweden)

    Martin-Fernandez Judith

    2012-10-01

    Full Text Available Abstract Background For the first time in France in a population-based survey, this study sought to investigate the potential impact of migration origin and the proportion of lifetime spent in mainland France on body mass index (BMI and overweight in adults living in the Paris metropolitan area. Methods A representative, population-based, random sample of the adult, French speaking population of the Paris metropolitan area was interviewed in 2005. Self-reported BMI (BMI = weight/height2 and overweight (BMI ≥ 25 were our 2 outcomes of interest. Two variables were constructed to estimate individuals’ migration origin: parental nationality and the proportion of lifetime spent in mainland France, as declared by the participants. We performed multilevel regression models among different gender and age groups, adjusted for demographics and socioeconomic status. Results In women, a parental origin in the Middle East or North Africa (MENA was associated with a higher risk of being overweight (especially before the age of 55 and a higher BMI (between 35 and 54 years of age, and so were women of Sub-Sahara African parental origin in the middle age category. Only in the youngest men ( Conclusions Our results plea for potential cultural determinants of overweight in the migrant and migrants-born populations in the French context of the capital region. Taking into account the people’ family and personal migration histories may be an important issue in public health research and policies on overweight and obesity prevention.

  7. Time spent in housework and leisure: links with parents' physiological recovery from work.

    Science.gov (United States)

    Saxbe, Darby E; Repetti, Rena L; Graesch, Anthony P

    2011-04-01

    Spouses' balancing of housework and leisure activities at home may affect their recovery from work. This paper reports on a study of everyday family life in which 30 dual-earner couples were tracked around their homes by researchers who recorded their locations and activities every 10 min. For women, the most frequently pursued activities at home were housework, communication, and leisure; husbands spent the most time in leisure activities, followed by communication and housework. Spouses differed in their total time at home and their proportion of time devoted to leisure and housework activities, with wives observed more often in housework and husbands observed more often in leisure activities. Both wives and husbands who devoted more time to housework had higher levels of evening cortisol and weaker afternoon-to-evening recovery. For wives, husbands' increased housework time also predicted stronger evening cortisol recovery. When both spouses' activities were entered in the same model, leisure predicted husbands' evening cortisol, such that husbands who apportioned more time to leisure, and whose wives apportioned less time to leisure, showed stronger after-work recovery. These results suggest that the division of labor within couples may have implications for physical health.

  8. The impact of a Critical Care Information System (CCIS) on time spent charting and in direct patient care by staff in the ICU: a review of the literature.

    Science.gov (United States)

    Mador, Rebecca L; Shaw, Nicola T

    2009-07-01

    The introduction of a Critical Care Information System (CCIS) into an intensive care unit (ICU) is purported to reduce the time health care providers (HCP) spend on documentation and increase the time available for direct patient care. However, there is a paucity of rigorous empirical research that has investigated these assertions. Moreover, those studies that have sought to elucidate the relationship between the introduction of a CCIS and the time spent by staff on in/direct patient care activities have published contradictory findings. The objective of this literature review is to establish the impact of a CCIS on time spent documenting and in direct patient care by staff in the ICU. Five electronic databases were searched including PubMed Central, EMBASE, CINAHL, IEEE Xplore, and the Cochrane Database of Systematic Reviews. Reference lists of all published papers were hand searched, and citations reviewed to identify extra papers. We included studies that were empirical articles, published in English, and provided original data on the impact of a CCIS on time spent documenting and in direct patient care by staff in the ICU. In total, 12 articles met the inclusion criteria. Workflow analysis (66%) and time-and-motion analysis (25%) were the most common forms of data collection. Three (25%) studies found an increase in time spent charting, five (42%) found no difference, and four (33%) studies reported a decrease. Results on the impact of a CCIS on direct patient care were similarly inconclusive. Due to the discrepant findings and several key methodological issues, the impact of a CCIS on time spent charting and in direct patient care remains unclear. This review highlights the need for an increase in rigorous empirical research in this area and provides recommendations for the design and implementation of future studies.

  9. Time spent for activation of non-profit studies in oncology in Italy.

    Directory of Open Access Journals (Sweden)

    Gianfranco De Feo

    Full Text Available AIM: The aim of this paper is to describe the time spent to activate oncological non-profit clinical trials promoted in Italy by the National Cancer Institute of Naples, following the implementation of recent European laws. METHODOLOGY: Data about the process of activation of 5 non-profit multicentre clinical trials were prospectively collected through a web-based system. The impact of European guidelines was assessed by comparing the efficiency of the process between applications started before and after the decree introducing in Italy the Clinical Trial Application form (MD-CTA. Outcomes of the descriptive analyses were the time to EC opinion, the time to administrative agreement signature after a positive EC opinion, and the cumulative percentage of submissions that came to closure (either positive or negative within four subsequent time cohorts. PRINCIPAL FINDINGS: From March 2007 to October 2009, 202 applications were submitted to 107 centres. Forty-four (59% applications of those submitted before were successful, compared to 71 (55% of those submitted after MD-CTA. Most of the failures were due to missing EC response (27% and 22% or administrative reasons (10% and 16%, before and after, respectively; very few (4% and 7% were due to EC refusal. The impact of the MD-CTA on time to EC opinion looked positive (median 4.1 vs 2.4 months, before and after, respectively but a subgroup analysis revealed that the impact was limited to a comparison biased by the selection of EC. After a positive EC opinion, there was no difference before and after MD-CTA in the time to administrative agreement signature (median 3.6 and 3.8 months, respectively. A trend to shortening time to closure of the whole submission process over the time was evident, with 58% of the applications coming to closure within 6 months from submission in the most recent cohort. CONCLUSIONS: In our experience there is reassuring evidence of a trend toward shortening the time spent to

  10. Data Mining Techniques to Estimate Plutonium, Initial Enrichment, Burnup, and Cooling Time in Spent Fuel Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Trellue, Holly Renee [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Fugate, Michael Lynn [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tobin, Stephen Joesph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-03-19

    The Next Generation Safeguards Initiative (NGSI), Office of Nonproliferation and Arms Control (NPAC), National Nuclear Security Administration (NNSA) of the U.S. Department of Energy (DOE) has sponsored a multi-laboratory, university, international partner collaboration to (1) detect replaced or missing pins from spent fuel assemblies (SFA) to confirm item integrity and deter diversion, (2) determine plutonium mass and related plutonium and uranium fissile mass parameters in SFAs, and (3) verify initial enrichment (IE), burnup (BU), and cooling time (CT) of facility declaration for SFAs. A wide variety of nondestructive assay (NDA) techniques were researched to achieve these goals [Veal, 2010 and Humphrey, 2012]. In addition, the project includes two related activities with facility-specific benefits: (1) determination of heat content and (2) determination of reactivity (multiplication). In this research, a subset of 11 integrated NDA techniques was researched using data mining solutions at Los Alamos National Laboratory (LANL) for their ability to achieve the above goals.

  11. Achieving the timely receipt of foreign research reactor spent nuclear fuel at the Savannah River site

    International Nuclear Information System (INIS)

    Brizes, C.M.; Clark, W.D; Thomas, J.; Andes, T.

    1998-01-01

    The May 1996 Record of Decision on a Proposed Nuclear Weapons Nonproliferation Policy Concerning Foreign Research Reactor Spent Nuclear Fuel states that the United States will accept spent nuclear fuel containing uranium of U.S.-origin from foreign research reactors through the year 2009. The best information available indicates that approximately 13,000 assemblies of Material Test Reactor (MTR) spent nuclear fuel from 29 countries are expected to be shipped to the Savannah River Site during the 13 years of the program. As of July 1998, 1,371 spent nuclear fuel assemblies from 12 foreign research reactors have been received at the SRS. That is, after more than two years of the FRR program (approximately 15 percent of the program time), 11 percent of the total assemblies have been received at SRS. Current projections show that most of the assemblies can be received by 2009, however if some of the eligible, non-participating countries decide to rejoin the program, a bottleneck would occur at the end of the program. Also adding to the potential for the bottleneck is a trend of shipments being moved out in the timeline. The Savannah River Site is working to be proactive in avoiding a bottleneck at the end of the program, but cooperation is required from all program participants to be successful. Activities currently in progress include inventory/information questionnaires, verifying fuel against cask(s) certificate of compliance (C. of C.), and collecting Appendix A information well in advance of shipping the SNF. The inventory/information sheets have been distributed to a select number of reactor facilities in the past, but work is in progress to refine the process. Information requested in the questionnaire includes inventory numbers, preferred shipping dates, and cask preferences. This information allows for improved shipment planning and helps to ensure that we are working to meet the needs of the reactor facilities. Current plans are to send the questionnaires to

  12. Long time storage containers for spent fuels and vitrified wastes: synthesis of the studies

    International Nuclear Information System (INIS)

    Beziat, A.

    2004-01-01

    This report presents a synthesis of the studies relatives to the containers devoted to the long time spent fuels storage and vitrified wastes packages. These studies were realized in the framework of the axis 3 of the law of 1991 on the radioactive wastes management. The first part is devoted to the presentation of the studies. The container sizing studies which constitute the first containment barrier are then presented. The material choice and the closed system are also detailed. The studies were validate by the realization of containers models and an associated demonstration program is proposed. A synthesis of the technical and economical studies allowed to determine the components and operation costs. (A.L.B.)

  13. Protective effect of time spent walking on risk of stroke in older men.

    Science.gov (United States)

    Jefferis, Barbara J; Whincup, Peter H; Papacosta, Olia; Wannamethee, S Goya

    2014-01-01

    Older adults have the highest risks of stroke and the lowest physical activity levels. It is important to quantify how walking (the predominant form of physical activity in older age) is associated with stroke. A total of 4252 men from a UK population-based cohort reported usual physical activity (regular walking, cycling, recreational activity, and sport) in 1998 to 2000. Nurses took fasting blood samples and made anthropometric measurements. Among 3435 ambulatory men free from cardiovascular disease and heart failure in 1998 to 2000, 195 first strokes occurred during 11-year follow-up. Men walked a median of 7 (interquartile range, 3-12) hours/wk; walking more hours was associated with lower heart rate, D-dimer, and higher forced expiratory volume in 1 second. Compared with men walking 0 to 3 hours/wk, men walking 4 to 7, 8 to 14, 15 to 21, and >22 hours had age- and region-adjusted hazard ratios (95% confidence intervals) for stroke of 0.89 (0.60-1.31), 0.63 (0.40-1.00), 0.68 (0.35-1.32), and 0.36 (0.14-0.91), respectively, P (trend)=0.006. Hazard ratios were somewhat attenuated by adjustment for established and novel risk markers (inflammatory and hemostatic markers and cardiac function [N-terminal pro-brain natriuretic peptide]) and walking pace, but linear trends remained. There was little evidence for a dose-response relationship between walking pace and stroke; comparing average pace or faster to a baseline of slow pace, the hazard ratio for stroke was 0.65 (95% confidence interval, 0.44-0.97), which was fully mediated by time spent walking. Time spent walking was associated with reduced risk of onset of stroke in dose-response fashion, independent of walking pace. Walking could form an important part of stroke-prevention strategies in older people.

  14. Is time spent playing video games associated with mental health, cognitive and social skills in young children?

    Science.gov (United States)

    Kovess-Masfety, Viviane; Keyes, Katherine; Hamilton, Ava; Hanson, Gregory; Bitfoi, Adina; Golitz, Dietmar; Koç, Ceren; Kuijpers, Rowella; Lesinskiene, Sigita; Mihova, Zlatka; Otten, Roy; Fermanian, Christophe; Pez, Ondine

    2016-01-01

    Background Video games are one of the favourite leisure activities of children; the influence on child health is usually perceived to be negative. The present study assessed the association between the amount of time spent playing video games and children mental health as well as cognitive and social skills. Methods Data were drawn from the School Children Mental Health Europe project conducted in six European Union countries (youth ages 6–11, n = 3195). Child mental health was assessed by parents and teachers using the Strengths and Difficulties Questionnaire and by children themselves with the Dominic Interactive. Child video game usage was reported by the parents. Teachers evaluated academic functioning. Multivariable logistic regressions were used. Results 20 % of the children played video games more than 5 h per week. Factors associated with time spent playing video games included being a boy, being older, and belonging to a medium size family. Having a less educated, single, inactive, or psychologically distressed mother decreased time spent playing video games. Children living in Western European countries were significantly less likely to have high video game usage (9.66 vs 20.49 %) though this was not homogenous. Once adjusted for child age and gender, number of children, mothers age, marital status, education, employment status, psychological distress, and region, high usage was associated with 1.75 times the odds of high intellectual functioning (95 % CI 1.31–2.33), and 1.88 times the odds of high overall school competence (95 % CI 1.44–2.47). Once controlled for high usage predictors, there were no significant associations with any child self-reported or mother- or teacher-reported mental health problems. High usage was associated with decreases in peer relationship problems [OR 0.41 (0.2–0.86) and in prosocial deficits (0.23 (0.07, 0.81)]. Conclusions Playing video games may have positive effects on young children. Understanding the mechanisms

  15. Is time spent playing video games associated with mental health, cognitive and social skills in young children?

    Science.gov (United States)

    Kovess-Masfety, Viviane; Keyes, Katherine; Hamilton, Ava; Hanson, Gregory; Bitfoi, Adina; Golitz, Dietmar; Koç, Ceren; Kuijpers, Rowella; Lesinskiene, Sigita; Mihova, Zlatka; Otten, Roy; Fermanian, Christophe; Pez, Ondine

    2016-03-01

    Video games are one of the favourite leisure activities of children; the influence on child health is usually perceived to be negative. The present study assessed the association between the amount of time spent playing video games and children mental health as well as cognitive and social skills. Data were drawn from the School Children Mental Health Europe project conducted in six European Union countries (youth ages 6-11, n = 3195). Child mental health was assessed by parents and teachers using the Strengths and Difficulties Questionnaire and by children themselves with the Dominic Interactive. Child video game usage was reported by the parents. Teachers evaluated academic functioning. Multivariable logistic regressions were used. 20 % of the children played video games more than 5 h per week. Factors associated with time spent playing video games included being a boy, being older, and belonging to a medium size family. Having a less educated, single, inactive, or psychologically distressed mother decreased time spent playing video games. Children living in Western European countries were significantly less likely to have high video game usage (9.66 vs 20.49 %) though this was not homogenous. Once adjusted for child age and gender, number of children, mothers age, marital status, education, employment status, psychological distress, and region, high usage was associated with 1.75 times the odds of high intellectual functioning (95 % CI 1.31-2.33), and 1.88 times the odds of high overall school competence (95 % CI 1.44-2.47). Once controlled for high usage predictors, there were no significant associations with any child self-reported or mother- or teacher-reported mental health problems. High usage was associated with decreases in peer relationship problems [OR 0.41 (0.2-0.86) and in prosocial deficits (0.23 (0.07, 0.81)]. Playing video games may have positive effects on young children. Understanding the mechanisms through which video game use may stimulate

  16. Measurement of informal care: an empirical study into the valid measurement of time spent on informal caregiving.

    NARCIS (Netherlands)

    Berg, Bernard van den; Spauwen, Pol

    2006-01-01

    The incorporation of informal care into economic evaluations of health care is troublesome. The debate focuses on the valuation of time spent on informal caregiving, while time measurement, a related and may be even a more important issue, tends to be neglected. Valid time measurement is a necessary

  17. Psychological, interpersonal, and clinical factors predicting time spent on physical activity among Mexican patients with hypertension

    Directory of Open Access Journals (Sweden)

    Ybarra Sagarduy JL

    2018-01-01

    Full Text Available José Luis Ybarra Sagarduy,1 Dacia Yurima Camacho Mata,1 José Moral de la Rubia,2 Julio Alfonso Piña López,3 José Luis Masud Yunes Zárraga4 1Unit of Social Work and Human Development, Autonomous University of Tamaulipas, Ciudad Victoria, 2School of Psychology, Autonomous University of Nuevo Leon, Monterrey, 3Independent Researcher, Hermosillo, 4Institute of Health and Safety Services for State Workers, Clinic for the Study and Prevention of the Chilhood Obesity, Ciudad Victoria, Mexico Background: It is widely known that physical activity is the key to the optimal management and clinical control of hypertension.Purpose: This research was conducted to identify factors that can predict the time spent on physical activity among Mexican adults with hypertension.Methods: This cross-sectional study was conducted among 182 Mexican patients with hypertension, who completed a set of self-administered questionnaires related to personality, social support, and medical adherence and health care behaviors, body mass index, and time since the disease diagnosis. Several path analyses were performed in order to test the predictors of the study behavior.Results: Lower tolerance to frustration, more tolerance to ambiguity, more effective social support, and less time since the disease diagnosis predicted more time spent on physical activity, accounting for 13.3% of the total variance. The final model shows a good fit to the sample data (pBS =0.235, χ2/gl =1.519, Jöreskog and Sörbom’s Goodness of Fit Index =0.987, adjusted modality =0.962, Bollen’s Incremental Fit Index =0.981, Bentler-Bonett Normed Fit Index =0.946, standardized root mean square residual =0.053.Conclusion: The performance of physical activity in patients with hypertension depends on a complex set of interactions between personal, interpersonal, and clinical variables. Understanding how these factors interact might enhance the design of interdisciplinary intervention programs so

  18. Direct Investigations Of The Immobilization Of Radionuclides In The Alteration Phases Of Spent Nuclear Fuel

    International Nuclear Information System (INIS)

    Burns, Peter C.; Finch, Robert J.; Wronkiewicz, David J.

    2003-01-01

    The safe disposal of the nation's nuclear waste in a geologic repository is one of the most significant and difficult scientific endeavors of the twenty-first century. Unique scientific challenges are posed by the very long-lived radioactivity of nuclear waste. Many radionuclides of vastly different chemical character must be retained by the repository for several thousand years. Some with longer half-lives, such as Pu-239 and Tc-99, need to be isolated for periods approaching a million years. In order to ensure the safety of a geologic repository, a detailed understanding of the mobility of radionuclides in complex natural systems is essential. Most of the radioactivity in a geological repository will be associated with spent nuclear fuel. In the United States spent fuel is derived from several sources. The majority is UO2 (LWR) spent fuel from commercial reactors. About 30,000 metric tons of spent fuel was in storage at commercial reactors by 1995, with the expectation that this quantity will more than double by 2010 (Integrated Data Report 1995). All spent fuel derived from commercial reactors is intended for eventual disposal in a geological repository. In addition, the DOE is the custodian of about 8000 metric tons of spent fuel, most of which is also intended for disposal in a geological repository. Although there are more than 250 types of spent fuel in the DOE inventory, the fuels may be broadly classified into (1) uranium metal fuel, (2) aluminum-based fuel, (3) mixed oxide (MOX) fuel containing substantial plutonium, and (4) graphite fuel (Colleen Shelton-Davis, personal communications, January 2000). Disposal of spent fuel in a geological repository requires detailed knowledge of the longterm behavior of the waste forms under repository conditions, as well as the fate of radionuclides released from the waste packages as containers are breached. The proposed Yucca Mountain repository is intended to hold 70,000 metric tons of high-level nuclear waste. Nine

  19. Mineralogic and petrologic investigation of post-test core samples from the Spent Fuel Test - Climax

    International Nuclear Information System (INIS)

    Ryerson, F.J.; Beiriger, J.

    1985-02-01

    We have characterized a suite of samples taken subsequent to the end of the Spent Fuel Test - Climax by petrographic and microanalytical techniques and determined their mineral assemblage, modal properties, and mineral chemistry. The samples were obtained immediately adjacent to the canister borehole at a variety of depths and positions within the canister drift, as well as radially outward from each canister hole. This method of sampling allows variations in post-test mineralogic properties to be evaluated on the basis of (1) depth along a particular canister hole and (2) position within the canister drift, with respect to the heat and radiation sources, and with respect to the pre - test samples. In no case did we find any significant correlation between the mineralogical properties and variables listed above. In short, the Spent Fuel Test - Climax has produced no identifiable mineralogical response in the Climax quartz monzonite. 12 refs., 11 figs., 5 tabs

  20. Investigation of water-logged spent fuel rods under dry storage conditions

    International Nuclear Information System (INIS)

    Kohli, R.; Pasupathi, V.

    1986-09-01

    Tests were conducted to determine the amount of moisture contained in breached, water-logged spent fuel rods and the rate of release. Two well-characterized BWR fuel rods with reactor-induced breaches were tested in a hot cell. These rods contained approximately 6 to 10 g of moisture, most of which was released during heating tests simulating normal cask drying operations. Additional testing with two intentionally defected fuel rods (BWR and PWR) was performed to evaluate the effect of the cladding breach on migration of moisture along the length of the fuel rod. The results showed that the moisture released from reactor-breached spent fuel rods was insufficient to cause degradation of fuel or dry storage system components

  1. Robotic Spent Fuel Monitoring – It is time to improve old approaches and old techniques!

    Energy Technology Data Exchange (ETDEWEB)

    Tobin, Stephen Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dasari, Venkateswara Rao [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Trellue, Holly Renee [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-12-13

    This report describes various approaches and techniques associated with robotic spent fuel monitoring. The purpose of this description is to improve the quality of measured signatures, reduce the inspection burden on the IAEA, and to provide frequent verification.

  2. Grey Literature Searching for Health Sciences Systematic Reviews: A Prospective Study of Time Spent and Resources Utilized.

    Science.gov (United States)

    Saleh, Ahlam A; Ratajeski, Melissa A; Bertolet, Marnie

    To identify estimates of time taken to search grey literature in support of health sciences systematic reviews and to identify searcher or systematic review characteristics that may impact resource selection or time spent searching. A survey was electronically distributed to searchers embarking on a new systematic review. Characteristics of the searcher and systematic review were collected along with time spent searching and what resources were searched. Time and resources were tabulated and resources were categorized as grey or non-grey. Data was analyzed using Kruskal-Wallis tests. Out of 81 original respondents, 21% followed through with completion of the surveys in their entirety. The median time spent searching all resources was 471 minutes, and of those a median of 85 minutes were spent searching grey literature. The median number of resources used in a systematic review search was four and the median number of grey literature sources searched was two. The amount of time spent searching was influenced by whether the systematic review was grant funded. Additionally, the number of resources searched was impacted by institution type and whether systematic review training was received. This study characterized the amount of time for conducting systematic review searches including searching the grey literature, in addition to the number and types of resources used. This may aid searchers in planning their time, along with providing benchmark information for future studies. This paper contributes by quantifying current grey literature search patterns and associating them with searcher and review characteristics. Further discussion and research into the search approach for grey literature in support of systematic reviews is encouraged.

  3. DETERMINANT FACTORS OF TIME SPENT ON FACEBOOK: BRAND COMMUNITY ENGAGEMENT AND USAGE TYPES

    OpenAIRE

    ULUSU, Yard. Doç. Dr. Yeşim

    2010-01-01

    Online  social  networks  have  integrated  into  the  computer  mediated  communication  (CMC) environment  in  the  past  few  years.  Social  Networks  such  as  Facebook,  Myspace,  Bebo  and  Twitter  are  web‐based services that allow people to create a public profile, share the connection with other users, and view and traverse  their  list  of  connections  in  common  network.  The  aim  of  this  study  is  to  find  factors  affecting  the amount  of  time  users  spent  on  Facebo...

  4. Teen worker safety training: methods used, lessons taught, and time spent.

    Science.gov (United States)

    Zierold, Kristina M

    2015-05-01

    Safety training is strongly endorsed as one way to prevent teens from performing dangerous tasks at work. The objective of this mixed methods study was to characterize the safety training that teenagers receive on the job. From 2010 through 2012, focus groups and a cross-sectional survey were conducted with working teens. The top methods of safety training reported were safety videos (42 percent) and safety lectures (25 percent). The top lessons reported by teens were "how to do my job" and "ways to spot hazards." Males, who were more likely to do dangerous tasks, received less safety training than females. Although most teens are getting safety training, it is inadequate. Lessons addressing safety behaviors are missing, training methods used are minimal, and the time spent is insignificant. More research is needed to understand what training methods and lessons should be used, and the appropriate safety training length for effectively preventing injury in working teens. In addition, more research evaluating the impact of high-quality safety training compared to poor safety training is needed to determine the best training programs for teens. © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  5. Energy beyond food: foraging theory informs time spent in thermals by a large soaring bird.

    Directory of Open Access Journals (Sweden)

    Emily L C Shepard

    Full Text Available Current understanding of how animals search for and exploit food resources is based on microeconomic models. Although widely used to examine feeding, such constructs should inform other energy-harvesting situations where theoretical assumptions are met. In fact, some animals extract non-food forms of energy from the environment, such as birds that soar in updraughts. This study examined whether the gains in potential energy (altitude followed efficiency-maximising predictions in the world's heaviest soaring bird, the Andean condor (Vultur gryphus. Animal-attached technology was used to record condor flight paths in three-dimensions. Tracks showed that time spent in patchy thermals was broadly consistent with a strategy to maximise the rate of potential energy gain. However, the rate of climb just prior to leaving a thermal increased with thermal strength and exit altitude. This suggests higher rates of energetic gain may not be advantageous where the resulting gain in altitude would lead to a reduction in the ability to search the ground for food. Consequently, soaring behaviour appeared to be modulated by the need to reconcile differing potential energy and food energy distributions. We suggest that foraging constructs may provide insight into the exploitation of non-food energy forms, and that non-food energy distributions may be more important in informing patterns of movement and residency over a range of scales than previously considered.

  6. Time's up. descriptive epidemiology of multi-morbidity and time spent on health related activity by older Australians: a time use survey.

    Directory of Open Access Journals (Sweden)

    Tanisha Jowsey

    Full Text Available Most Western health systems remain single illness orientated despite the growing prevalence of multi-morbidity. Identifying how much time people with multiple chronic conditions spend managing their health will help policy makers and health service providers make decisions about areas of patient need for support. This article presents findings from an Australian study concerning the time spent on health related activity by older adults (aged 50 years and over, most of whom had multiple chronic conditions. A recall questionnaire was developed, piloted, and adjusted. Sampling was undertaken through three bodies; the Lung Foundation Australia (COPD sub-sample, National Diabetes Services Scheme (Diabetes sub-sample and National Seniors Australia (Seniors sub-sample. Questionnaires were mailed out during 2011 to 10,600 older adults living in Australia. 2540 survey responses were received and analysed. Descriptive analyses were completed to obtain median values for the hours spent on each activity per month. The mean number of chronic conditions was 3.7 in the COPD sub-sample, 3.4 in the Diabetes sub-sample and 2.0 in the NSA sub-sample. The study identified a clear trend of increased time use associated with increased number of chronic conditions. Median monthly time use was 5-16 hours per month overall for our three sub-samples. For respondents in the top decile with five or more chronic conditions the median time use was equivalent to two to three hours per day, and if exercise is included in the calculations, respondents spent from between five and eight hours per day: an amount similar to full-time work. Multi-morbidity imposes considerable time burdens on patients. Ageing is associated with increasing rates of multi-morbidity. Many older adults are facing high demands on their time to manage their health in the face of decreasing energy and mobility. Their time use must be considered in health service delivery and health system reform.

  7. Determinants of Children's Use of and Time Spent in Fast-Food and Full-Service Restaurants

    Science.gov (United States)

    McIntosh, Alex; Kubena, Karen S.; Tolle, Glen; Dean, Wesley; Kim, Mi-Jeong; Jan, Jie-Sheng; Anding, Jenna

    2011-01-01

    Objective: Identify parental and children's determinants of children's use of and time spent in fast-food (FF) and full-service (FS) restaurants. Design: Analysis of cross-sectional data. Setting: Parents were interviewed by phone; children were interviewed in their homes. Participants: Parents and children ages 9-11 or 13-15 from 312 families…

  8. Is time spent playing video games associated with mental health, cognitive and social skills in young children?

    NARCIS (Netherlands)

    Kovess-Masfety, V.; Keyes, K.M.; Hamilton, A.; Hanson, G.; Bitfoi, A.; Golitz, D.; Koç, C.; Kuijpers, R.C.W.M.; Lesinskiene, S.; Mihova, Z.; Otten, R.; Fermanian, C.; Pez, O.

    2016-01-01

    Video games are one of the favourite leisure activities of children; the influence on child health is usually perceived to be negative. The present study assessed the association between the amount of time spent playing video games and children mental health as well as cognitive and social skills.

  9. Human mobility and time spent at destination: impact on spatial epidemic spreading.

    Science.gov (United States)

    Poletto, Chiara; Tizzoni, Michele; Colizza, Vittoria

    2013-12-07

    Host mobility plays a fundamental role in the spatial spread of infectious diseases. Previous theoretical works based on the integration of network theory into the metapopulation framework have shown that the heterogeneities that characterize real mobility networks favor the propagation of epidemics. Nevertheless, the studies conducted so far assumed the mobility process to be either Markovian (in which the memory of the origin of each traveler is lost) or non-Markovian with a fixed traveling time scale (in which individuals travel to a destination and come back at a constant rate). Available statistics however show that the time spent by travelers at destination is characterized by wide fluctuations, ranging from a single day up to several months. Such varying length of stay crucially affects the chance and duration of mixing events among hosts and may therefore have a strong impact on the spread of an emerging disease. Here, we present an analytical and a computational study of epidemic processes on a complex subpopulation network where travelers have memory of their origin and spend a heterogeneously distributed time interval at their destination. Through analytical calculations and numerical simulations we show that the heterogeneity of the length of stay alters the expression of the threshold between local outbreak and global invasion, and, moreover, it changes the epidemic behavior of the system in case of a global outbreak. Additionally, our theoretical framework allows us to study the effect of changes in the traveling behavior in response to the infection, by considering a scenario in which sick individuals do not leave their home location. Finally, we compare the results of our non-Markovian framework with those obtained with a classic Markovian approach and find relevant differences between the two, in the estimate of the epidemic invasion potential, as well as of the timing and the pattern of its spatial spread. These results highlight the importance of

  10. The Effects of Employment Status and Daily Stressors on Time Spent on Daily Household Chores in Middle-Aged and Older Adults

    Science.gov (United States)

    Wong, Jen D.; Almeida, David M.

    2013-01-01

    Purpose of the study: This study examines how employment status (worker vs. retiree) and life course influences (age, gender, and marital status) are associated with time spent on daily household chores. Second, this study assesses whether the associations between daily stressors and time spent on daily household chores differ as a function of…

  11. Investigation of 3H and 14C inventory and distribution in spent BWR fuel rods

    International Nuclear Information System (INIS)

    Bleier, A.; Beuerle, M.; Neeb, K.H.

    1984-10-01

    In order to obtain reliable data for fuel reprocessing and waste disposal, the T and C-14 inventory, distribution and behaviour was investigated on a typical LWR fuel rod discharged from a BWR plant. The results showed that 50 ± 5% of the T generated in the fuel is present in the cladding after reactor operation. The remainder of the T stays with the fuel. Related to the reactor power the total T inventory corresponds to a T production rate of 19 000 Ci/GW e . a. The C-14 built up in the fuel represents approximately 60% of the C-14 inventory of the BWR fuel rod. The remaining part of C-14 (about 40%) experimentally determined by this analysis for the first time is generated in the cladding. From the total C-14 inventory a C-14 production rate of 17,5 Ci/GW e . a can be calculated. The fill gas contains only negligible fractions of both nuclides. The results obtained in this program are generally in good agreement with the data of theoretical estimates and with results of earlier investigations on PWR fuel rods. (orig.) [de

  12. High-burnup/low-cooling-time fuel carrying capacity of the GA-4 and GA-9 spent fuel shipping casks

    International Nuclear Information System (INIS)

    Boshoven, J.K.; Hopf, J.E.

    1994-01-01

    In response to utilities' projected needs to ship higher burnup spent fuel, General Atomics (GA) has performed shielding and thermal analysis for the GA-4 and GA-9 legal weight shipping casks to determine the minimum cooling times for various burnup levels for fully loaded GA-4 and GA-9 casks and reduced payloads for the casks. Tables are provided in the paper which show the minimum cooling time for a given burnup and payload for each of the casks. The analyses show that the GA-4 and GA-9 casks can carry at least as many high-burnup and/or short-cooling-time spent fuel assemblies as present day shipping casks. In addition, the GA casks are able to carry at least twice as many assemblies as the present day shipping casks if the spent fuel burnup levels and/or cooling times are open-quotes coolerclose quotes or open-quotes as coolclose quotes as their design basis fuels. The increased shipping capacity for these more common open-quotes coolerclose quotes assemblies allows fewer shipments and therefore increases the efficiency and lowers predicted risks of the transport system

  13. Spent nuclear fuel storage - Basic concept

    International Nuclear Information System (INIS)

    Krempel, Ascanio; Santos, Cicero D. Pacifici dos; Sato, Heitor Hitoshi; Magalhaes, Leonardo de

    2009-01-01

    According to the procedures adopted in others countries in the world, the spent nuclear fuel elements burned to produce electrical energy in the Brazilian Nuclear Power Plant of Angra do Reis, Central Nuclear Almirante Alvaro Alberto - CNAAA will be stored for a long time. Such procedure will allow the next generation to decide how they will handle those materials. In the future, the reprocessing of the nuclear fuel assemblies could be a good solution in order to have additional energy resource and also to decrease the volume of discarded materials. This decision will be done in the future according to the new studies and investigations that are being studied around the world. The present proposal to handle the nuclear spent fuel is to storage it for a long period of time, under institutional control. Therefore, the aim of this paper is to introduce a proposal of a basic concept of spent fuel storage, which involves the construction of a new storage building at site, in order to increase the present storage capacity of spent fuel assemblies in CNAAA installation; the concept of the spent fuel transportation casks that will transfer the spent fuel assemblies from the power plants to the Spent Fuel Complementary Storage Building and later on from this building to the Long Term Intermediate Storage of Spent Fuel; the concept of the spent fuel canister and finally the basic concept of the spent fuel long term storage. (author)

  14. Investigation on structural analysis computer program of spent nuclear fuel shipping cask

    International Nuclear Information System (INIS)

    Yagawa, Ganki; Ikushima, Takeshi.

    1987-10-01

    This report describes the results done by the Sub-Committee of Research Cooperation Committee (RC-62) of the Japan Society of Mechanical Engineers under the trust of the Japan Atomic Energy Research Institute. The principal fulfilments and accomplishments are summarized as follows: (1) Regarding the survey of structural analysis methods of spent fuel shipping cask, several documents, which explain the features and applications of the exclusive computer programs for impact analysis on the basis of 2 or 3 dimensional finite element or difference methods such as HONDO, STEALTH and DYNA-3D, were reviewed. (2) In comparative evaluation of the existing computer programs, the common benchmark test problems for 9 m vertical drop impact of the axisymmetric lead cylinder with and without stainless steel clads were adopted where the calculational evaluations for taking into account the strain rate effect were carried out. (3) Evaluation of impact analysis algorithm of computer programs were conducted and the requirements for computer programs to be developed in future and an index for further studies have been clarified. (author)

  15. Bullying Behavior, Parents' Work Hours and Early Adolescents' Perceptions of Time Spent with Parents

    Science.gov (United States)

    Christie-Mizell, C. Andre; Keil, Jacqueline M.; Laske, Mary Therese; Stewart, Jennifer

    2011-01-01

    This research investigates the relationships among bullying behavior, mother's and father's work hours, and early adolescents' perceptions of whether they spend sufficient time with their parents. In cross-sectional models, we find maternal work hours are modestly associated with increases in bullying behavior. However, in more rigorous change…

  16. The Relation between the Time Mothers and Children Spent Together and the Children's Trait Emotional Intelligence

    Science.gov (United States)

    Alegre, Albert

    2012-01-01

    Background: Parenting practices have been shown to predict children's emotional intelligence. The time that mothers and children spend in joint activity is an important aspect of the parent-child relationship, and it has been found to be influential in different domains of children's development. However, it has not been investigated in relation…

  17. Comparison of the Amount of Time Spent on Computer Games and Aggressive Behavior in Male Middle School Students of Tehran

    OpenAIRE

    Mehrangiz Shoaa Kazemi; Zahra Shahabinezhad

    2016-01-01

    Background and Objectives: Modern technologies have a prominent role in adolescent's daily life. These technologies include specific cultural and moral patterns, which could be highly effective on adolescents. This research aimed at comparing the amount of time spent on computer games and aggressive behavior in male middle school students of Tehran. Materials and Methods: This study had a descriptive design. The study population included all male students of middle school of Tehran, and th...

  18. Changes in time spent walking and the risk of incident dementia in older Japanese people: the Ohsaki Cohort 2006 Study.

    Science.gov (United States)

    Tomata, Yasutake; Zhang, Shu; Sugiyama, Kemmyo; Kaiho, Yu; Sugawara, Yumi; Tsuji, Ichiro

    2017-09-01

    the impact of long-term changes in physical activity during adulthood in the context of primary prevention of dementia has not been addressed previously. to study the relationship between changes in time spent walking after middle age and incident dementia in older Japanese individuals. we conducted a cohort study of 6,909 disability-free Japanese individuals aged ≥65 years who lived in Ohsaki City, Japan. In both 1994 and 2006, the individual amount of time spent walking per day was assessed using a self-reported questionnaire (dementia were retrieved from the public Long-term Care Insurance (LTCI) Database, in which participants were followed up for 5.7 years (between April 2007 and November 2012). The Cox model was used for estimating the multivariate-adjusted hazard ratios (HRs) of incident dementia. the 5.7-year incidence of dementia was 9.2%. Compared with persons who remained in the lowest category of time spent walking (dementia: the multivariate-adjusted HR (95% confidence intervals) was 0.72 (0.53 and 0.97). these results suggest that maintaining a higher level of physical activity after middle age may be a key strategy for prevention of dementia in older age. © The Author 2017. Published by Oxford University Press on behalf of the British Geriatrics Society.All rights reserved. For permissions, please email: journals.permissions@oup.com

  19. Breast Intensity-Modulated Radiation Therapy Reduces Time Spent With Acute Dermatitis for Women of All Breast Sizes During Radiation

    International Nuclear Information System (INIS)

    Freedman, Gary M.; Li Tianyu; Nicolaou, Nicos; Chen Yan; Ma, Charlie C.-M.; Anderson, Penny R.

    2009-01-01

    Purpose: To study the time spent with radiation-induced dermatitis during a course of radiation therapy for breast cancer in women treated with conventional or intensity-modulated radiation therapy (IMRT). Methods and Materials: The study population consisted of 804 consecutive women with early-stage breast cancer treated with breast-conserving surgery and radiation from 2001 to 2006. All patients were treated with whole-breast radiation followed by a boost to the tumor bed. Whole-breast radiation consisted of conventional wedged photon tangents (n = 405) earlier in the study period and mostly of photon IMRT (n = 399) in later years. All patients had acute dermatitis graded each week of treatment. Results: The breakdown of the cases of maximum acute dermatitis by grade was as follows: 3%, Grade 0; 34%, Grade 1; 61%, Grade 2; and 2%, Grade 3. The breakdown of cases of maximum toxicity by technique was as follows: 48%, Grade 0/1, and 52%, Grade 2/3, for IMRT; and 25%, Grade 0/1, and 75%, Grade 2/3, for conventional radiation therapy (p < 0.0001). The IMRT patients spent 82% of weeks during treatment with Grade 0/1 dermatitis and 18% with Grade 2/3 dermatitis, compared with 29% and 71% of patients, respectively, treated with conventional radiation (p < 0.0001). Furthermore, the time spent with Grade 2/3 toxicity was decreased in IMRT patients with small (p = 0.0015), medium (p < 0.0001), and large (p < 0.0001) breasts. Conclusions: Breast IMRT is associated with a significant decrease both in the time spent during treatment with Grade 2/3 dermatitis and in the maximum severity of dermatitis compared with that associated with conventional radiation, regardless of breast size.

  20. Time-dependent variation of the neutron multiplication factor in spent fuel storage

    Energy Technology Data Exchange (ETDEWEB)

    Leotlela, M.J. [Univ. of the Witwatersrand, Johannesburg (South Africa). School of Physics; Eskom, Johannesburg (South Africa). Regulations and Licensing, Koeberg Operating Unit; Olifant, T. [Cape Town Univ. (South Africa). Dept. of Electrical Engineering and Nuclear Power Studies; Koeberg Nuclear Power Station, Cape Town (South Africa). Operating Dept.; Petr, I. [Univ. of the Witwatersrand, Johannesburg (South Africa). School of Physics

    2017-12-15

    After spent fuel assemblies have been discharged from the reactor, reactivity will fluctuate as the cooling period progresses because of changes in the number density of fissile nuclides and neutron absorber nuclides. The purpose of this project was (1) to quantify the contribution of each individual nuclide to the reactivity of the fissile system, (2) to identify nuclides that are responsible for the fluctuation in reactivity, and (3) to determine the effect of the number of nuclides on reactivity. This paper will present the results of the study of the behaviour of the k{sub eff} with respect to variation in the duration of the cooling period during storage.

  1. Multinomial model and zero-inflated gamma model to study time spent on leisure time physical activity: an example of ELSA-Brasil.

    Science.gov (United States)

    Nobre, Aline Araújo; Carvalho, Marilia Sá; Griep, Rosane Härter; Fonseca, Maria de Jesus Mendes da; Melo, Enirtes Caetano Prates; Santos, Itamar de Souza; Chor, Dora

    2017-08-17

    To compare two methodological approaches: the multinomial model and the zero-inflated gamma model, evaluating the factors associated with the practice and amount of time spent on leisure time physical activity. Data collected from 14,823 baseline participants in the Longitudinal Study of Adult Health (ELSA-Brasil - Estudo Longitudinal de Saúde do Adulto ) have been analysed. Regular leisure time physical activity has been measured using the leisure time physical activity module of the International Physical Activity Questionnaire. The explanatory variables considered were gender, age, education level, and annual per capita family income. The main advantage of the zero-inflated gamma model over the multinomial model is that it estimates mean time (minutes per week) spent on leisure time physical activity. For example, on average, men spent 28 minutes/week longer on leisure time physical activity than women did. The most sedentary groups were young women with low education level and income. The zero-inflated gamma model, which is rarely used in epidemiological studies, can give more appropriate answers in several situations. In our case, we have obtained important information on the main determinants of the duration of leisure time physical activity. This information can help guide efforts towards the most vulnerable groups since physical inactivity is associated with different diseases and even premature death.

  2. Multinomial model and zero-inflated gamma model to study time spent on leisure time physical activity: an example of ELSA-Brasil

    Directory of Open Access Journals (Sweden)

    Aline Araújo Nobre

    2017-08-01

    Full Text Available ABSTRACT OBJECTIVE To compare two methodological approaches: the multinomial model and the zero-inflated gamma model, evaluating the factors associated with the practice and amount of time spent on leisure time physical activity. METHODS Data collected from 14,823 baseline participants in the Longitudinal Study of Adult Health (ELSA-Brasil – Estudo Longitudinal de Saúde do Adulto have been analysed. Regular leisure time physical activity has been measured using the leisure time physical activity module of the International Physical Activity Questionnaire. The explanatory variables considered were gender, age, education level, and annual per capita family income. RESULTS The main advantage of the zero-inflated gamma model over the multinomial model is that it estimates mean time (minutes per week spent on leisure time physical activity. For example, on average, men spent 28 minutes/week longer on leisure time physical activity than women did. The most sedentary groups were young women with low education level and income CONCLUSIONS The zero-inflated gamma model, which is rarely used in epidemiological studies, can give more appropriate answers in several situations. In our case, we have obtained important information on the main determinants of the duration of leisure time physical activity. This information can help guide efforts towards the most vulnerable groups since physical inactivity is associated with different diseases and even premature death.

  3. Measurement and Analysis Plan for Investigation of Spent-Fuel Assay Using Lead Slowing-Down Spectroscopy

    International Nuclear Information System (INIS)

    Smith, Leon E.; Haas, Derek A.; Gavron, Victor A.; Imel, G.R.; Ressler, Jennifer J.; Bowyer, Sonya M.; Danon, Y.; Beller, D.

    2009-01-01

    Under funding from the Department of Energy Office of Nuclear Energy's Materials, Protection, Accounting, and Control for Transmutation (MPACT) program (formerly the Advanced Fuel Cycle Initiative Safeguards Campaign), Pacific Northwest National Laboratory (PNNL) and Los Alamos National Laboratory (LANL) are collaborating to study the viability of lead slowing-down spectroscopy (LSDS) for spent-fuel assay. Based on the results of previous simulation studies conducted by PNNL and LANL to estimate potential LSDS performance, a more comprehensive study of LSDS viability has been defined. That study includes benchmarking measurements, development and testing of key enabling instrumentation, and continued study of time-spectra analysis methods. This report satisfies the requirements for a PNNL/LANL deliverable that describes the objectives, plans and contributing organizations for a comprehensive three-year study of LSDS for spent-fuel assay. This deliverable was generated largely during the LSDS workshop held on August 25-26, 2009 at Rensselaer Polytechnic Institute (RPI). The workshop itself was a prominent milestone in the FY09 MPACT project and is also described within this report.

  4. HFIR spent fuel management alternatives

    International Nuclear Information System (INIS)

    Begovich, J.M.; Green, V.M.; Shappert, L.B.; Lotts, A.L.

    1992-01-01

    The High Flux Isotope Reactor (HFIR) at Martin Marietta Energy Systems' Oak Ridge National Laboratory (ORNL) has been unable to ship its spent fuel to Savannah River Site (SRS) for reprocessing since 1985. The HFIR storage pools are expected to fill up in the February 1994 to February 1995 time frame. If a management altemative to existing HFIR pool storage is not identified and implemented before the HFIR pools are full, the HFIR will be forced to shut down. This study investigated several alternatives for managing the HFIR spent fuel, attempting to identify options that could be implemented before the HFIR pools are full. The options investigated were: installing a dedicated dry cask storage facility at ORNL, increasing HFIR pool storage capacity by clearing the HFIR pools of debris and either close-packing or stacking the spent fuel elements, storing the spent fuel at another ORNL pool, storing the spent fuel in one or more hot cells at ORNL, and shipping the spent fuel offsite for reprocessing or storage elsewhere

  5. Spent fuel storage and isolation

    International Nuclear Information System (INIS)

    Bensky, M.S.; Kurzeka, W.J.; Bauer, A.A.; Carr, J.A.; Matthews, S.C.

    1979-02-01

    The principal spent fuel activities conducted within the commercial waste and spent fuel within the Commercial Waste and Spent Fuel Packaging Program are: simulated near-surface (drywell) storage demonstrations at Hanford and the Nevada Test Site; surface (sealed storage cask) and drywell demonstrations at the Nevada Test Site; and spent fuel receiving and packaging facility conceptual design. These investigations are described

  6. Maternal employment, acculturation, and time spent in food-related behaviors among Hispanic mothers in the United States. Evidence from the American Time Use Survey.

    Science.gov (United States)

    Sliwa, Sarah A; Must, Aviva; Peréa, Flavia; Economos, Christina D

    2015-04-01

    Employment is a major factor underlying im/migration patterns. Unfortunately, lower diet quality and higher rates of obesity appear to be unintended consequences of moving to the US. Changes in food preparation practices may be a factor underlying dietary acculturation. The relationships between employment, acculturation, and food-related time use in Hispanic families have received relatively little attention. We used cross-sectional data collected from Hispanic mothers (ages 18-65) with at least one child employment, acculturation (US-born vs. im/migrant), and time spent in food preparation and family dinner. Regression models were estimated separately for the employed and the non-working and were adjusted for Hispanic origin group, socio-demographic and household characteristics. Working an eight-hour day was associated with spending 38 fewer minutes in food preparation (-38.0 ± SE 4.8, p < 001). Although being US-born was associated with spending fewer minutes in food preparation, this relationship varied by origin group. Acculturation did not appear to modify the relationship between hours worked and time spent in food preparation or family dinner. Mothers who worked late hours spent less time eating the evening meal with their families (-9.8 ± SE 1.3). Although an eight-hour workday was associated with a significant reduction in food preparation time, an unexpected result is that, for working mothers, additional time spent in paid work is not associated with the duration of family dinner later that day. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Impact of rivastigmine on costs and on time spent in caregiving for families of patients with Alzheimer's disease.

    Science.gov (United States)

    Marin, Deborah; Amaya, Karine; Casciano, Roman; Puder, Katherine L; Casciano, Julian; Chang, Sobin; Snyder, Edward H; Cheng, Isaac; Cuccia, Anthony J

    2003-12-01

    Alzheimer's disease (AD) places a significant burden on health care systems worldwide. As new treatments are developed, their cost-effectiveness is often assessed to help health care professionals make informed decisions. In addition to the more common practice of assessing direct medical costs, indirect costs, including time spent in caregiving, should be evaluated. This study examined the potential effects of the dual cholinesterase inhibitor rivastigmine (Exelon) on caregivers of patients with AD. Results from two 26-week, placebo-controlled trials have demonstrated the clinically relevant and statistically significant efficacy of rivastigmine (6-12 mg/day) compared to placebo, on cognition, activities of daily living, and global functioning. By delaying progression of AD, significant savings in caregiver burden are anticipated, as measured by time spent caregiving and its related costs. Data collected in a prospective, observational study of AD patients and their caregivers were used to establish the relationship between disease severity (based on Mini-Mental State Examination [MMSE] score) and time spent caregiving (according to the 5-item Caregivers Activity Survey score). A significant correlation was observed between the two scores (N = 43, r = -.56, p patients with mild AD (MMSE score 21-30), resulting in a total savings of approximately 11,253 dollars. Treatment of patients with moderately severe AD was also evaluated. The trend was similar but the impact was less, suggesting an economic benefit to early therapy. Early diagnosis and a pharmacologic intervention that allows the patients to remain at home longer by delaying disease progression would have a beneficial impact on patients, caregivers, and payers, and should therefore be encouraged through initiatives designed to identify and treat patients early in the course of disease.

  8. Daily time spent indoors in German homes--baseline data for the assessment of indoor exposure of German occupants.

    Science.gov (United States)

    Brasche, Sabine; Bischof, Wolfgang

    2005-01-01

    Comprehensive time-activity studies, for use as a basis for estimates of personal exposure, are not readily available in Germany. This analysis of time spent indoors at home is based on data from "Dampness and mould in homes" (2000/ 2001)--a study of about 12,000 persons living in 5530 randomly selected apartments and houses in Germany. The results show the mean times per day people in Germany spend in their homes, classified by gender, age group, building location, city size, region, building type, owner-occupier status, number of people at home, smoking and ventilation habits, moisture emission and ill health factors such as asthma, allergy and number of acute respiratory infections per year. The overall mean time spent at home, 15.7 h per, is in accordance with results from US-American (15.6 h/day) and Canadian (15.8 h/day) human activity surveys carried out in the nineties, as well as being consistent with the German Environmental Survey (1990/92) and a small German study in 1987.

  9. Investigations of the Quality of The Reclaim of Spent Moulding Sands with Organic Binders

    Directory of Open Access Journals (Sweden)

    Dańko R.

    2012-09-01

    Full Text Available Modern investigation methods and equipment for the quality estimation of the moulding sands matrices with organic binders, in their circulation process, are presented in the paper. These methods, utilising the special equipment combined with the authors investigation methods developed in the Faculty of Foundry Engineering, AGH the University of Science and Technology, allow for the better estimation of the matrix quality. Moulding sands systems with organic binders require an in-depth approach to factors deciding on the matrix technological suitability as well as on their environmental impact. Into modern methods allowing for the better assessment of the matrix quality belongs the grain size analysis of the reclaimed material performed by means of the laser diffraction and also the estimation of the moulding sand gas evolution rate and identification of the emitted gases and their BTEX group gases content, since they are specially hazardous from the point of view of the Occupational Safety and Health.

  10. Gamma spectrometric characterization of short cooling time nuclear spent fuels using hemispheric CdZnTe detectors

    CERN Document Server

    Lebrun, A; Szabó, J L; Arenas-Carrasco, J; Arlt, R; Dubreuil, A; Esmailpur-Kazerouni, K

    2000-01-01

    After years of cooling, nuclear spent fuel gamma emissions are mainly due to caesium isotopes which are emitters at 605, 662 and 796-801 keV. Extensive work has been done on such fuels using various CdTe or CdZnTe probes. When fuels have to be measured after short cooling time (during NPP outage) the spectrum is much more complex due to the important contributions of niobium and zirconium in the 700 keV range. For the first time in a nuclear power plant, four spent fuels of the Kozloduy VVER reactor no 4 were measured during outage, 37 days after shutdown of the reactor. In such conditions, good resolution is of particular interest, so a 20 mm sup 3 hemispheric crystal was used with a resolution better than 7 keV at 662 keV. This paper presents the experimental device and analyzes the results which show that CdZnTe commercially available detectors enabled us to perform a semi-quantitative determination of the burn-up after a short cooling time. In addition, it is discussed how a burn-up evolution code (CESAR)...

  11. Investigations of the Quality of the Reclaim of Spent Moulding Sands with Organic Binders

    Directory of Open Access Journals (Sweden)

    R. Dańko

    2012-09-01

    Full Text Available Modern investigation methods and equipment for the quality estimation of the moulding sands matrices with organic binders, in theircirculation process, are presented in the paper. These methods, utilising the special equipment combined with the authors investigationmethods developed in the Faculty of Foundry Engineering, AGH the University of Science and Technology, allow for the better estimationof the matrix quality. Moulding sands systems with organic binders require an in-depth approach to factors deciding on the matrixtechnological suitability as well as on their environmental impact. Into modern methods allowing for the better assessment of the matrixquality belongs the grain size analysis of the reclaimed material performed by means of the laser diffraction and also the estimation of the moulding sand gas evolution rate and identification of the emitted gases and their BTEX group gases content, since they are specially hazardous from the point of view of the Occupational Safety and Health.

  12. Spent fuels program

    International Nuclear Information System (INIS)

    Shappert, L.B.

    1983-01-01

    The goal of this task is to support the Domestic Spent Fuel Storage Program through studies involving the transport of spent fuel. A catalog was developed to provide authoritative, timely, and accessible transportation information for persons involved in the transport of irradiated reactor fuel. The catalog, drafted and submitted to the Transportation Technology Center, Sandia National Laboratories, for their review and approval, covers such topics as federal, state, and local regulations, spent fuel characteristics, cask characteristics, transportation costs, and emergency response information

  13. The influence of evaluation protocol on time spent exercising at a high level of oxygen uptake during continuous cycling.

    Science.gov (United States)

    Merry, K L; Glaister, M; Howatson, G; Van Someren, K

    2015-10-01

    This study evaluated the effects of protocol variation on the time spent exercising at ≥95% V̇O2max during cycle ergometer trials performed at the exercise intensity associated with V̇O2max (iV̇O2max). Nine male triathletes (age: 32±10 years; body mass: 73.3±6.1 kg; stature: 1.79±0.07 m; V̇O2max: 3.58±0.45 L.min(-1)) performed four exercise tests. During tests 1 and 2, participants performed a maximal incremental cycle ergometer test using different stage durations (1 min and 3 min) for the determination of iV̇O2max (1 min) and iV̇O2max (3 min). During tests 3 and 4, participants performed a continuous bout of exhaustive cycling at iV̇O2max (1 min) (CONT1) and iV̇O2max (3 min) (CONT3). iV̇O2max (1 min) was significantly greater (Pexercising continuously at iV̇O2max, time spent at ≥95% V̇O2max is influenced by the initial measurement of iV̇O2max.

  14. Bioleaching of spent Ni-Cd batteries by continuous flow system: Effect of hydraulic retention time and process load

    International Nuclear Information System (INIS)

    Zhao Ling; Yang Dong; Zhu Nanwen

    2008-01-01

    Spent Ni-Cd batteries bring a severe environmental problem that needs to be solved urgently. A novel continuous flow two-step leaching system based on bioleaching was introduced to dissolve heavy metals in batteries. It consists of an acidifying reactor which was used to culture indigenous thiobacilli and a leaching reactor which was used to leach metals from spent batteries. The indigenous acidophilic thiobacilli in sewage sludge was used as the microorganisms and the sludge itself as culture medium. Bioleaching tests at different hydraulic retention time (HRT) and process load in the leaching reactor were performed. The results showed that the longer the HRT (1, 3, 6, 9 and 15 days) was, the more time required to achieve the complete leaching of Ni, Cd and Co. The maximum dissolution of cadmium and cobalt was achieved at higher pH values (3.0-4.5) while the leaching of nickel hydroxide and nickel in metallic form (Ni 0 ) were obtained separately in different acidity (pH 2.5-3.5). It cost about 25, 30 and more than 40 days to remove all of the three heavy metals with the process load of two, four and eight Ni-Cd batteries under the conditions that the ingoing bio-sulphuric acid was 1 L d -1 and HRT was 3 days

  15. Bioleaching of spent Ni-Cd batteries by continuous flow system: effect of hydraulic retention time and process load.

    Science.gov (United States)

    Zhao, Ling; Yang, Dong; Zhu, Nan-Wen

    2008-12-30

    Spent Ni-Cd batteries bring a severe environmental problem that needs to be solved urgently. A novel continuous flow two-step leaching system based on bioleaching was introduced to dissolve heavy metals in batteries. It consists of an acidifying reactor which was used to culture indigenous thiobacilli and a leaching reactor which was used to leach metals from spent batteries. The indigenous acidophilic thiobacilli in sewage sludge was used as the microorganisms and the sludge itself as culture medium. Bioleaching tests at different hydraulic retention time (HRT) and process load in the leaching reactor were performed. The results showed that the longer the HRT (1, 3, 6, 9 and 15 days) was, the more time required to achieve the complete leaching of Ni, Cd and Co. The maximum dissolution of cadmium and cobalt was achieved at higher pH values (3.0-4.5) while the leaching of nickel hydroxide and nickel in metallic form (Ni0) were obtained separately in different acidity (pH 2.5-3.5). It cost about 25, 30 and more than 40 days to remove all of the three heavy metals with the process load of two, four and eight Ni-Cd batteries under the conditions that the ingoing bio-sulphuric acid was 1Ld(-1) and HRT was 3 days.

  16. Bioleaching of spent Ni-Cd batteries by continuous flow system: Effect of hydraulic retention time and process load

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Ling; Yang Dong [School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Zhu Nanwen [School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China)], E-mail: nwzhu@sina.com

    2008-12-30

    Spent Ni-Cd batteries bring a severe environmental problem that needs to be solved urgently. A novel continuous flow two-step leaching system based on bioleaching was introduced to dissolve heavy metals in batteries. It consists of an acidifying reactor which was used to culture indigenous thiobacilli and a leaching reactor which was used to leach metals from spent batteries. The indigenous acidophilic thiobacilli in sewage sludge was used as the microorganisms and the sludge itself as culture medium. Bioleaching tests at different hydraulic retention time (HRT) and process load in the leaching reactor were performed. The results showed that the longer the HRT (1, 3, 6, 9 and 15 days) was, the more time required to achieve the complete leaching of Ni, Cd and Co. The maximum dissolution of cadmium and cobalt was achieved at higher pH values (3.0-4.5) while the leaching of nickel hydroxide and nickel in metallic form (Ni{sup 0}) were obtained separately in different acidity (pH 2.5-3.5). It cost about 25, 30 and more than 40 days to remove all of the three heavy metals with the process load of two, four and eight Ni-Cd batteries under the conditions that the ingoing bio-sulphuric acid was 1 L d{sup -1} and HRT was 3 days.

  17. Time spent by Brazilian students in different modes of transport going to school: changes over a decade (2001-2011

    Directory of Open Access Journals (Sweden)

    Kelly Samara Silva

    2014-11-01

    Full Text Available To examine changes in the time spent in each mode of transportation used for going to school by gender and age among adolescents from Santa Catarina State, Brazil. Two school-based surveys were performed in 2001 (N = 5,028 and 2011 (N = 6,529 in high school students (15-19 years old. The mode of transportation (on foot; by bicycle; by bus; car/motorcycle and the time spent for commuting to school were assessed. Active commuting increased for short trips in both genders (male: 25.1% to 36.7%; female: 18.8% to 29.2% and in all ages (15-16 years: 21% to 32.7%; 17-19 years: 21.9% to 32.4%, and declined for longer trips in males (30.5% to 21.9% and in 15-16 years old students (25.7% to 34.7%. Car/motorcycle use has doubled for short trips in males (38.1% to 65.9% and in 17-19 years old students (37.7% to 62.7%, while the use of buses remained stable in both genders. Our findings contribute to discussions on public policy focusing on the design of safe environments to promote active commuting to schools, particularly to decrease the use of motorized transport for short trips.

  18. An investigation into the hazards associated with the maritime transport of spent nuclear reactor fuel to the British Isles

    International Nuclear Information System (INIS)

    1980-01-01

    Interim results are presented from an investigation into the potential hazard from maritime transport of spent reactor fuel. From a review of official safety studies the most severe accident is identified as a prolonged shipboard fire of 9 hours or more. According to studies performed for the International Atomic Energy Agency by the Batelle Laboratories such a fire could fail all fuel elements and release volatile radionuclides such as caesium to the environment. The consequences of such an accident are investigated for a release to the Irish Sea from a fire damaged vessel. Consequences are analysed for a release to the continental shelf waters following sinking, and also for an atmospheric release close to a conurbation. The port of Barrow is taken as an example. The report concludes that either of these events could have catastrophic consequences: the Irish Sea might have to be closed to fisheries and in the case of an atmospheric release large scale evacuation would be necessary to prevent loss of life. (author)

  19. Comparison of Objectively Measured and Self-reported Time Spent Sitting

    DEFF Research Database (Denmark)

    Lagersted-Olsen, Julie; Korshøj, M; Skotte, J

    2014-01-01

    Until recently, methods for objective quantification of sitting time have been lacking. The aim of this study was to validate self-reported measures against objectively measured total sitting time and longest continuous time with uninterrupted sitting during working hours, leisure time on workday...... a retrospective 7-day questionnaire. A generalized linear model showed the difference between the methods. No significant correlations were found between objective and self-reported sitting time (r...

  20. Measuring the opportunity loss of time spent boarding admitted patients in the emergency department: a multihospital analysis.

    Science.gov (United States)

    Lucas, Raymond; Farley, Heather; Twanmoh, Joseph; Urumov, Andrej; Evans, Bruce; Olsen, Nils

    2009-01-01

    Emergency department (ED) crowding is an international crisis affecting the timeliness and quality of patient care. Boarding of admitted patients in the ED is recognized as a major contributor to ED crowding. The opportunity loss of this time is the benefit or value it could produce if it were used for something else. In crowded EDs, the typical alternative use of this time is to treat patients waiting to be seen. Various ED performance benchmarks related to inpatient boarding have been proposed, but they are not commonly reported and have yet to be evaluated to determine whether they correlate with the opportunity loss of time used for boarding. This study quantified several measures of ED boarding in a variety of hospital settings and looked for correlations between them and the opportunity loss of the time spent on boarding. In particular, average boarding time per admission was found to be easy to measure. Results revealed that it had a near-perfect linear correlation with opportunity loss. The opportunity loss of every 30 minutes of average boarding time equaled the time required to see 3.5 percent of the ED's daily census. For busy hospitals, the opportunity loss allowed sufficient time for staff to be able to see up to 36 additional patients per day. This correlation suggests that average boarding time per admission may be useful in evaluating efforts to reduce ED crowding and improve patient care.

  1. Who's cooking? Time spent preparing food by gender, income and household composition

    OpenAIRE

    Mancino, Lisa; Newman, Constance

    2006-01-01

    We use the American Time Use Survey data and multivariate analysis to explore how time allocated to food preparation differs across income groups, household composition (number of adults and presence of children), and employment status of adults in the household.

  2. Time Spent in Face-to-Face Patient Care and Work Outside the Examination Room

    OpenAIRE

    Gottschalk, Andrew; Flocke, Susan A.

    2005-01-01

    PURPOSE Contrary to physicians’ concerns that face-to-face patient time is decreasing, data from the National Ambulatory Medical Care Survey (NAMCS) indicate that between 1988 and 1998, durations of primary care outpatient visits have increased. This study documented how physicians spend time during the workday, including time outside the examination room, and compared observed face-to-face patient care time with that reported in NAMCS.

  3. Investigation of pharmaceuticals and medical devices containing 90Y extracted from high radioactive liquid waste in spent-fuel reprocessing

    International Nuclear Information System (INIS)

    Hosoma, Takashi

    2012-07-01

    Pharmaceuticals and medical devices containing radioactive 90 Y are realized, approved and placed on the international market where three products are available in Europe and the United States, and one product in Japan. These products are used not for diagnosis but for treatment by internal irradiation. It was estimated from the deliberative report of the approval in Japan that 90 Y was extracted in Europe from high radioactive liquid waste (HALW) yielded in spent-fuel reprocessing. In this report, products placed on the market and physical properties were reviewed, reasons of the realization and conditions to realize succeeding products were estimated, extraction method was compared with other methods, technical subjects, and relevant regulations were investigated. Although a medical device containing radioactive 90 Y has been studied in Japan and one pharmaceutical product was approved, a breakthrough would be necessary to put 90 Y utilization beyond alternative treatments. The breakthrough would become be promising; for example, if conventional treatments could be supported by technical development to deliver 90 Y more sharply to the target with shorter serum half-life. Extraction of 90 Y nuclide from HALW has advantages over thermal neutron irradiation of natural nuclide, a system is envisioned where 90 Sr as a parent nuclide is separated in the reprocessing then transported to and stored in a factory of radiopharmaceuticals followed by 90 Y extraction on demand. (author)

  4. Seismic VSP and HSP surveys on preliminary investigation areas in Finland for final disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Keskinen, J.; Cosma, C.; Heikkinen, P.

    1992-10-01

    Seismic reflection surveys in boreholes were carried out for Teollisuuden Voima Oy at five sites in Finland (Eurajoki Olkiluoto, Hyrynsalmi Veitsivaara, Konginkangas Kivetty, Kuhmo Romuvaara and Sievi Syyry). The vertical Seismic Profiling (VSP) surveys were a part of the investigation programme for the final disposal of spent nuclear fuel. The purpose was to detect fractured zones, lithological contacts and other anomalies in the structure of the rockmass and to determine their position and orientation. Horizontal Seismic Profiling (HSP) was used at the Olkiluoto site, additionally to VSP. The data has been organized in profiles containing seismograms recorded from the same shotpoint (shot gathers). One of the most powerful processing methods used with this project has been the Image Space Filtering, a new technique, which has been developed (in the project) for seismic reflection studies in crystalline rock. The method can be applied with other rock types where steeply inclined or vertical anomalies are of interest. It acts like a multichannel filter, enhancing the reflected events and also as an interpretation tool, to estimate the strength and position of the reflectors. This approach has been of great help in emphasizing the weak reflections from uneven and sometimes vanishing interfaces encountered in crystalline

  5. An Investigation into Spent Coffee Waste as a Renewable Source of Bioactive Compounds and Industrially Important Sugars

    Directory of Open Access Journals (Sweden)

    Damhan S. Scully

    2016-11-01

    Full Text Available Conventional coffee brewing techniques generate vast quantities of spent espresso grounds (SEGs rich in lignocellulose and valuable bioactives. These bioactive compounds can be exploited as a nutraceutical or used in a range of food products, while breakdown of lignocellulose generates metabolizable sugars that can be used for the production of various high-value products such as biofuels, amino acids and enzymes. Response surface methodology (RSM was used to optimize the enzymatic saccharification of lignocellulose in SEGs following a hydrothermal pretreatment. A maximum reducing sugar yield was obtained at the following optimized hydrolysis conditions: 4.97 g of pretreated SEGs, 120 h reaction time, and 1246 and 250 µL of cellulase and hemicellulase, respectively. Industrially important sugars (glucose, galactose and mannose were identified as the principal hydrolysis products under the studied conditions. Total flavonoids (p = 0.0002, total polyphenols (p = 0.03 and DPPH free-radical scavenging activity (p = 0.004 increased significantly after processing. A 14-fold increase in caffeine levels was also observed. This study provides insight into SEGs as a promising source of industrially important sugars and polyphenols.

  6. Learning style versus time spent studying and career choice: Which is associated with success in a combined undergraduate anatomy and physiology course?

    Science.gov (United States)

    Farkas, Gary J; Mazurek, Ewa; Marone, Jane R

    2016-01-01

    The VARK learning style is a pedagogical focus in health care education. This study examines relationships of course performance vs. VARK learning preference, study time, and career plan among students enrolled in an undergraduate anatomy and physiology course at a large urban university. Students (n = 492) from the fall semester course completed a survey consisting of the VARK questionnaire, gender, academic year, career plans, and estimated hours spent per week in combined classroom and study time. Seventy-eight percent of students reported spending 15 or fewer hours per week studying. Study time and overall course score correlated significantly for the class as a whole (r = 0.111, P = 0.013), which was mainly due to lecture (r = 0.118, P = 0.009) performance. No significant differences were found among students grouped by learning styles. When corrected for academic year, overall course scores (mean ± SEM) for students planning to enter dentistry, medicine, optometry or pharmacy (79.89 ± 0.88%) were significantly higher than those of students planning to enter physical or occupational therapies (74.53 ± 1.15%; P = 0.033), as well as nurse/physician assistant programs (73.60 ± 1.3%; P = 0.040). Time spent studying was not significantly associated with either learning style or career choice. Our findings suggest that specific career goals and study time, not learning preferences, are associated with better performance among a diverse group of students in an undergraduate anatomy and physiology course. However, the extent to which prior academic preparation, cultural norms, and socioeconomic factors influenced these results requires further investigation. © 2015 American Association of Anatomists.

  7. A Study of Time Spent Working at Learning Centers. Technical Report #17.

    Science.gov (United States)

    Omori, Sharon; And Others

    This study examined the proportion of time children in the Kamehameha Early Education Program schools spend at actual school work in learning centers. Systematic time-sampled observations using multiple observers were conducted in December-January and again in March-April. The subjects, 12 children (6 kindergarteners and 6 first graders) were…

  8. The Effects of Social Environments on Time Spent Gaming: Focusing on the Effects of Communities and Neighborhoods.

    Science.gov (United States)

    Lim, Tee Teng; Jung, Sun Young; Kim, Eunyi

    2018-04-01

    This study examined the impact of community and neighborhood on time spent computer gaming. Computer gaming for over 20 hours a week was set as the cutoff line for "engaged use" of computer games. For the analysis, this study analyzed data for about 1,800 subjects who participated in the Korean Children and Youth Panel Survey. The main findings are as follows: first, structural community characteristics and neighborhood social capital affected the engaged use of computer games. Second, adolescents who reside in regions with a higher divorce rate or higher residential mobility were likely to exhibit engaged use of computer games. Third, adolescents who highly perceive neighborhood social capital exhibited lower possibility of engaged use of computer games. Based on these findings, practical implications and directions for further study are suggested.

  9. Direct investigations of the immobilization of radionuclides in the alteration phases of spent nuclear fuel. 1998 annual progress report

    International Nuclear Information System (INIS)

    Burns, P.C.; Finch, R.J.

    1998-01-01

    'In an oxidizing environment, such as in the proposed repository at Yucca Mountain, rapid alteration rates are expected for spent nuclear fuel. Lab.-scale simulations have repeatedly shown that the dominant alteration products under repository conditions will be uranyl phases. There is an inadequate database that relates to the effects of the alteration products on the release of radionuclides, but this information is essential to provide a radionuclide release estimate. It is likely that many of the radionuclides contained in the fuel will be incorporated into the alteration products that form, potentially with a profound impact on the future mobility of radionuclides in the repository. The authors objective is to characterize the incorporation of radionuclides into alteration products by synthesis of uranyl phases doped with radionuclides, appropriate surrogate elements, or non-radioactive isotopes, followed by detailed phase characterization by diffraction and spectroscopic techniques. The research will permit a more realistic estimate of the release rates of the radionuclides from the near-field environment. This report summarizes work after 8 months of a 3-year project. The objective of investigating radionuclide incorporation in uranyl phases has required the development of synthesis techniques for various uranyl phases that are expected to form under repository conditions. The authors have synthesized and determined the structures of several uranyl phases that are new to science and that may be important alteration products under repository conditions. They have also undertaken the determination and refinement of the crystal structures of various uranyl phases that are likely to form under repository conditions. Other experiments include the investigation of the ion-exchange properties of uranyl phases under repository conditions.'

  10. Nurses' daily life: gender relations from the time spent in hospital

    Directory of Open Access Journals (Sweden)

    Audrey Vidal Pereira

    2015-10-01

    Full Text Available Objective: to analyze the everyday life of nurses through the sexual work division as well as through interdependence relations and the time in hospital.Method: quanti-qualitative study, based on the Time Use Survey and in Norbert Elias's Configuration Theory of Interdependencies. Daily shifts distribution record, directed by 42 participants - with self-confrontation - by interviews which drew dialogues on subjective aspects of the everyday experiences related to use of time, based on a job at a university hospital. The theoretical intake that founded data analysis was based on concepts of conflicts of interest, power struggles, sexual work division and polychronic-monochronic concepts - whether the work environment demands multitasking nurses or not.Results: time records allowed to observe differences between the groups studied, useful to identify conflicts, tensions, power struggles and gender inequalities in interviewees' everyday affairs that do not only affect physical and mental health, but also their way of life.Conclusion: the analytical path pointed out the need for public policies that promote equity in gender relations, keeping at sight the exercise of plural discourses and tolerant stances capable to respect differences between individual and collective time.

  11. Nurses' daily life: gender relations from the time spent in hospital.

    Science.gov (United States)

    Pereira, Audrey Vidal

    2015-01-01

    to analyze the everyday life of nurses through the sexual work division as well as through interdependence relations and the time in hospital. quanti-qualitative study, based on the Time Use Survey and in Norbert Elias's Configuration Theory of Interdependencies. Daily shifts distribution record, directed by 42 participants--with self-confrontation--by interviews which drew dialogues on subjective aspects of the everyday experiences related to use of time, based on a job at a university hospital. The theoretical intake that founded data analysis was based on concepts of conflicts of interest, power struggles, sexual work division and polychronic-monochronic concepts--whether the work environment demands multitasking nurses or not. time records allowed to observe differences between the groups studied, useful to identify conflicts, tensions, power struggles and gender inequalities in interviewees' everyday affairs that do not only affect physical and mental health, but also their way of life. the analytical path pointed out the need for public policies that promote equity in gender relations, keeping at sight the exercise of plural discourses and tolerant stances capable to respect differences between individual and collective time.

  12. Ojibway Adolescent Time Spent with Parents/Elders as Related to Delinquency and Court Adjudication Experiences.

    Science.gov (United States)

    Zitzow, Darryl

    1990-01-01

    Among 94 Ojibway adolescents, those with a history of delinquency or court adjudication were less likely to spend time with their families and were more likely to report dysfunctional family situations and negative feelings toward family. Recommendations are presented for family support and skills development in reservation communities. (SV)

  13. Investigations of Low Temperature Time Dependent Cracking

    Energy Technology Data Exchange (ETDEWEB)

    Van der Sluys, W A; Robitz, E S; Young, B A; Bloom, J

    2002-09-30

    The objective of this project was to investigate metallurgical and mechanical phenomena associated with time dependent cracking of cold bent carbon steel piping at temperatures between 327 C and 360 C. Boiler piping failures have demonstrated that understanding the fundamental metallurgical and mechanical parameters controlling these failures is insufficient to eliminate it from the field. The results of the project consisted of the development of a testing methodology to reproduce low temperature time dependent cracking in laboratory specimens. This methodology was used to evaluate the cracking resistance of candidate heats in order to identify the factors that enhance cracking sensitivity. The resultant data was integrated into current available life prediction tools.

  14. A Between- and Within-Person Analysis of Parenting And Time Spent in Criminogenic Settings during Adolescence: The Role of Self-Control And Delinquent Attitudes

    Science.gov (United States)

    Janssen, Heleen J.; Bruinsma, Gerben J. N.; Dekovic, Maja; Eichelsheim, Veroni I.

    2018-01-01

    Although spending time in criminogenic settings is increasingly recognized as an explanation for adolescent delinquency, little is known about its determinants. The current study aims to examine the extent to which (change in) self-control and (change in) delinquent attitudes relate to (change in) time spent in criminogenic settings, and the…

  15. Investigations of Physicochemical Properties and Thermal Utilisation of Dusts Generated in the Mechanical Reclamation Process of Spent Moulding Sands

    Directory of Open Access Journals (Sweden)

    Dańko R.

    2015-04-01

    Full Text Available The after reclamation dusts originated from various foundry plants, applying moulding sands with organic binding agents, mostly resins, are characterised by different properties in dependence of the used binders, reclamation systems, spent sands overheating degree and the efficiency of the system dedusting the reclaimed material operating in individual foundry plants.

  16. Lead Slowing-Down Spectrometry Time Spectral Analysis for Spent Fuel Assay: FY12 Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Kulisek, Jonathan A.; Anderson, Kevin K.; Casella, Andrew M.; Siciliano, Edward R.; Warren, Glen A.

    2012-09-28

    .g. Pb stack size, neutron source location) of an LSDS for the purpose of assaying used fuel assemblies. Sensitivity studies were conducted that provide insight as to how the LSDS instrument can be improved by making it more sensitive to the center of the fuel assemblies. In FY2013, PNNL will continue efforts to develop and refine design requirements of an LSDS for the ultimate purpose of assaying used fuel assemblies. Future efforts will be directed toward more extensive experimental benchmarking of currently implemented time-spectra analysis algorithms.

  17. Social relationships enhance the time spent eating and intake of a novel diet in pregnant Hanwoo (Bos taurus coreanae) heifers.

    Science.gov (United States)

    Shin, Dong-Han; Kang, Hyun-Min; Seo, Seongwon

    2017-01-01

    The objective of this study was to evaluate the effects of social relationships on the feed intake, eating behavior, and growth, upon exposure to a novel diet, in Hanwoo ( Bos taurus coreanae ) heifers during pregnancy. Twenty-four pregnant Hanwoo heifers, averaging 438 ± 27.8 kg in weight, 21 months in age, and 194 ± 8.5 days in pregnancy, were involved in a two-month (eight weeks) experiment. The heifers were randomly assigned to either the single housing group (SG; one individual per pen, n = 12), or the paired housing group (PG; two individuals per pen, n = 12). All pens were of the same size (5 × 5 m) and provided with one feed bin, which automatically recorded the individual feed intake and eating behavior. As the experiment began, the diet of the heifers was switched from a total mixed ration (TMR; 250 g/kg ryegrass straw and 750 g/kg concentrate mix) to a forage-only diet (mixed hay cubes composed of 500 g/kg alfalfa, 250 g/kg timothy, and 250 g/kg blue grass hay). The heifers were fed ad libitum twice a day. The individual feed intake and eating behavior were recorded daily throughout the experiment, and body weights (BWs) were measured every four weeks before the morning feeding. PG animals visited the feed bin 22% less often than SG. PG, however, stayed 39% longer in the feed bin and consumed 40% more feed per visit, compared with SG. Consequently, PG heifers spent 23% more time in eating and had 16% more daily dry matter intake than SG during the experiment. Average daily gain during the experimental period tended to be greater in PG than in SG. When pregnant Hanwoo heifers encountered a novel diet, social relationships (i.e., presence of a pen-mate) enhanced their time spent eating and feed intake. Social interactions, even with an unfamiliar individual, may be helpful for pregnant Hanwoo heifers cope with a diet challenge compared to solitary situation.

  18. Closure of the Spent Fuel Repository in Forsmark - Studies of alternative concepts for sealing of ramp, shafts and investigation boreholes

    Energy Technology Data Exchange (ETDEWEB)

    Gylling, Bjoern [SKB AB, Stockholm (Sweden); Luterkort, David [SGI, Stockholm (Sweden); Johansson, Roland [Miljoe- och Energikonsult AB, Ekeroe (Sweden)

    2012-12-15

    In March 2011, SKB submitted applications under the Nuclear Activities Act and the Environmental Code for the construction and operation of a final repository for spent nuclear fuel in Forsmark. An important supporting document for the application under the Nuclear Activities Act was the SR-Site safety assessment. As a part of the work with the application and as background material for SR-Site, SKB prepared production reports, including the closure production report. The closure production report presented definitions, requirements and design premises, a reference design and the initial state for repository closure. SR-Site evaluated the reference design and related design premises that were presented in the closure production report. SR-Site thereby concluded that the design premises on which the reference design were based are adequate. Relaxing the requirements would require additional sensitivity analyses focusing on the hydraulic properties of the access, main and transport tunnels. SR-Site further concluded that the reference design could likely be simplified without violating the current design premises. Furthermore, additional simplifications could probably be made if the design premises could be revised. This has been studied in the project 'Closure - concept studies', whose results are presented in this report. SR-Site also evaluated the reference design for investigation boreholes that is presented in the production report. The evaluation showed that the impact of improper borehole seals is very moderate. Further, SR-Site concludes that the current design premises are appropriate but possibly too strict, since even open boreholes seem to have a limited impact on the groundwater flow in the repository. Since it might be difficult to inspect the outcome of the current design of borehole sealing, it could be of interest to assess whether a solution that may result in higher effective permeability of the borehole seals would provide sufficiently

  19. Time well spent

    DEFF Research Database (Denmark)

    Fallesen, Peter

    2013-01-01

    adult outcomes, others find null effects. This study shows that differences in the average duration of foster care stays explain parts of these discordant findings and then test how foster care duration shapes later life outcomes using administrative data on 7 220 children. The children experienced...

  20. Integrated account of method, site selection and programme prior to the site investigation phase[Planning for a Swedish repository for spent nuclear fuels

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-12-01

    applications and have these applications reviewed by the appropriate authorities. An analysis of conceivable alternatives for managing and disposing of spent nuclear fuel has confirmed that deep geological disposal according to the KBS-3 method has the best prospects of meeting all requirements. The alternative of putting off a decision until some future time (the zero alternative) does not appear tenable. The assessment of long-term safety shows that the prospects of building a safe deep repository in the Swedish bedrock are good. Independent Swedish and international review of the safety assessment confirm that the body of data in this respect is adequate for the siting process to proceed to the site investigation phase. A fuller summary is given below of the account given in this report of method as well as site selection and programme for the site investigation phase. The point of departure for the account is the review comments made by the regulatory authorities and the Government's decision regarding RD and D-Programme 98. In its decision, the Government stipulated conditions for SKB's continued research and development programme. The analysis of alternative system designs was to be supplemented, mainly with regard to the zero alternative and very deep boreholes. Furthermore, the Government decided that SKB shall submit an integrated evaluation of completed feasibility studies and other background material for selection of sites for site investigations and present a clear programme for site investigations.

  1. Time Spent on Dedicated Patient Care and Documentation Tasks Before and After the Introduction of a Structured and Standardized Electronic Health Record.

    Science.gov (United States)

    Joukes, Erik; Abu-Hanna, Ameen; Cornet, Ronald; de Keizer, Nicolette F

    2018-01-01

    Physicians spend around 35% of their time documenting patient data. They are concerned that adopting a structured and standardized electronic health record (EHR) will lead to more time documenting and less time for patient care, especially during consultations. This study measures the effect of the introduction of a structured and standardized EHR on documentation time and time for dedicated patient care during outpatient consultations. We measured physicians' time spent on four task categories during outpatient consultations: documentation, patient care, peer communication, and other activities. Physicians covered various specialties from two university hospitals that jointly implemented a structured and standardized EHR. Preimplementation, one hospital used a legacy-EHR, and one primarily paper-based records. The same physicians were observed 2 to 6 months before and 6 to 8 months after implementation.We analyzed consultation duration, and percentage of time spent on each task category. Differences in time distribution before and after implementation were tested using multilevel linear regression. We observed 24 physicians (162 hours, 439 consultations). We found no significant difference in consultation duration or number of consultations per hour. In the legacy-EHR center, we found the implementation associated with a significant decrease in time spent on dedicated patient care (-8.5%). In contrast, in the previously paper-based center, we found a significant increase in dedicated time spent on documentation (8.3%) and decrease in time on combined patient care and documentation (-4.6%). The effect on dedicated documentation time significantly differed between centers. Implementation of a structured and standardized EHR was associated with 8.5% decrease in time for dedicated patient care during consultations in one center and 8.3% increase in dedicated documentation time in another center. These results are in line with physicians' concerns that the introduction

  2. Comparison of the Amount of Time Spent on Computer Games and Aggressive Behavior in Male Middle School Students of Tehran

    Directory of Open Access Journals (Sweden)

    Mehrangiz Shoaa Kazemi

    2016-12-01

    Full Text Available Background and Objectives: Modern technologies have a prominent role in adolescent's daily life. These technologies include specific cultural and moral patterns, which could be highly effective on adolescents. This research aimed at comparing the amount of time spent on computer games and aggressive behavior in male middle school students of Tehran. Materials and Methods: This study had a descriptive design. The study population included all male students of middle school of Tehran, and the sample included 120 male students, of which 60 were dependent on computer games with aggressive behavior and 60 were non-dependent on computer games with normal behavior; the sample was randomly selected from Tehran regions (south, north, west, and east regions with random multi-stage sampling. Data were gathered using questionnaires, including Aggressive Questionnaire (AGQ and a researcher-made questionnaire consisting of 10 multiple questions that measure the use or non-use of computer games. Data were analyzed using SPSS-19 statistical software. For data analysis, Pearson correlation and t test were used. Results: The results showed that there was a meaningful relationship between computer gaming and aggressive behavior and also between duration of using computer games and aggressive behaviors (P <0.05. Conclusions: According to the results, it seems that children could be kept safe from the adverse effects of computer games by controlling the duration and the type of the games that they play.

  3. Investigation of the thermal performance of a vertical two-phase closed thermosyphon as a passive cooling system for a nuclear reactor spent fuel storage pool

    Energy Technology Data Exchange (ETDEWEB)

    Kusuma, Mukhsinun Hadi; Putra, Nandy; Imawan, Ficky Augusta [Heat Transfer Laboratory, Department of Mechanical Engineering Universitas Indonesia, Kampus (Indonesia); Antariksawan, Anhar Riza [Centre for Nuclear Reactor Safety and Technology, National Nuclear Energy Agency of Indonesia (BATAN), Kawasan Puspiptek Serpong (Indonesia)

    2017-04-15

    The decay heat that is produced by nuclear reactor spent fuel must be cooled in a spent fuel storage pool. A wickless heat pipe or a vertical two-phase closed thermosyphon (TPCT) is used to remove this decay heat. The objective of this research is to investigate the thermal performance of a prototype model for a large-scale vertical TPCT as a passive cooling system for a nuclear research reactor spent fuel storage pool. An experimental investigation and numerical simulation using RELAP5/MOD 3.2 were used to investigate the TPCT thermal performance. The effects of the initial pressure, filling ratio, and heat load were analyzed. Demineralized water was used as the TPCT working fluid. The cooled water was circulated in the water jacket as a cooling system. The experimental results show that the best thermal performance was obtained at a thermal resistance of 0.22°C/W, the lowest initial pressure, a filling ratio of 60%, and a high evaporator heat load. The simulation model that was experimentally validated showed a pattern and trend line similar to those of the experiment and can be used to predict the heat transfer phenomena of TPCT with varying inputs.

  4. The Influence of Instructional Climates on Time Spent in Management Tasks and Physical Activity of 2nd-Grade Students during Physical Education

    Science.gov (United States)

    Logan, Samuel W.; Robinson, Leah E.; Webster, E. Kipling; Rudisill, Mary E.

    2015-01-01

    The purpose of this study is to determine the effect of two physical education (PE) instructional climates (mastery, performance) on the percentage of time students spent in a) moderate-to-vigorous physical activity (MVPA) and b) management tasks during PE in 2nd-grade students. Forty-eight 2nd graders (mastery, n = 23; performance, n = 25)…

  5. Smart cities, healthy kids: the association between neighbourhood design and children's physical activity and time spent sedentary.

    Science.gov (United States)

    Esliger, Dale W; Sherar, Lauren B; Muhajarine, Nazeem

    2012-07-26

    To determine whether, and to what extent, a relation exists between neighbourhood design and children's physical activity and sedentary behaviours in Saskatoon. Three neighbourhood designs were assessed: 1) core neighbourhoods developed before 1930 that follow a grid pattern, 2) fractured-grid pattern neighbourhoods that were developed between the 1930s and mid-1960s, and 3) curvilinear-pattern neighbourhoods that were developed between the mid-1960s through to 1998. Children aged 10-14 years (N=455; mean age 11.7 years), grouped by the neighbourhoods they resided in, had their physical activity and sedentary behaviour objectively measured by accelerometry for 7 days. ANCOVA and MANCOVA (multivariate analysis of covariance) models were used to assess group differences (p<0.05). Group differences were apparent on weekdays but not on weekend days. When age, sex and family income had been controlled for, children living in fractured-grid neighbourhoods had, on average, 83 and 55 fewer accelerometer counts per minute on weekdays than the children in the core and curvilinear-pattern neighbourhoods, respectively. Further analyses showed that the children in the fractured-grid neighbourhoods accumulated 15 and 9 fewer minutes of moderate-to-vigorous physical activity per day and had a greater time spent in sedentary behaviour (23 and 17 minutes) than those in core and curvilinear-pattern neighbourhoods, respectively. These data suggest that in Saskatoon there is a relation between neighbourhood design and children's physical activity and sedentary behaviours. Further work is needed to tease out which features of the built environments have the greatest impact on these important lifestyle behaviours. This information, offered in the context of ongoing development of neighbourhoods, as we see in Saskatoon, is critical to an evidence-informed approach to urban development and planning.

  6. Is It Time Well Spent? The Relationship between Time Management Behaviours, Perceived Effectiveness and Work-Related Morale and Distress in a University Context

    Science.gov (United States)

    Kearns, Hugh; Gardiner, Maria

    2007-01-01

    Despite the high "guru-factor" in time management, few claims have been subjected to empirical investigation. This study tests the claims that people who manage their time well perceive themselves to be more effective and feel less stressed. University staff and students were utilized to investigate the relationship between time management related…

  7. Direct Measurement of Initial Enrichment, Burn-up and Cooling Time of Spent Fuel Assembly with a Differential Die-Away Technique Based Instrument

    International Nuclear Information System (INIS)

    Henzl, Vladimir; Swinhoe, Martyn T.; Tobin, Stephen J.

    2012-01-01

    An outline of this presentation of what a Differential Die-Away (DDA) instrument can do are: (1) Principle of operation of DDA instrument; (2) Determination of initial enrichment (IE) (σ DDA response increases (die-away time is longer) with increasing fissile content; and (2) Spent fuel => DDA response decreases (die-away time is shorter) with higher burn-up (i.e. more neutron absorbers present).

  8. Determinants of Sedentary Behavior, Motivation, Barriers and Strategies to Reduce Sitting Time in Older Women: A Qualitative Investigation

    OpenAIRE

    Chastin, Sebastien F. M.; Fitzpatrick, Nicole; Andrews, Michelle; DiCroce, Natalie

    2014-01-01

    Sedentary behavior defined as time spent non-exercising seated or reclining posture has been identified has a health risk and associated with frailty and disablement for older adults. Older adults are the most sedentary segment of society. To date no study has investigated the determinants of sedentary behavior in older adults. This study reports a qualitative investigation of the determinants of sedentary behavior, strategies and motivator to reduce sitting time by structured interviews in ...

  9. Spent fuel workshop'2002

    International Nuclear Information System (INIS)

    Poinssot, Ch.

    2002-01-01

    This document gathers the transparencies of the presentations given at the 2002 spent fuel workshop: Session 1 - Research Projects: Overview on the IN CAN PROCESSES European project (M. Cowper), Overview on the SPENT FUEL STABILITY European project (C. Poinssot), Overview on the French R and D project on spent fuel long term evolution, PRECCI (C. Poinssot); Session 2 - Spent Fuel Oxidation: Oxidation of uranium dioxide single crystals (F. Garrido), Experimental results on SF oxidation and new modeling approach (L. Desgranges), LWR spent fuel oxidation - effects of burn-up and humidity (B. Hanson), An approach to modeling CANDU fuel oxidation under dry storage conditions (P. Taylor); Session 3 - Spent Fuel Dissolution Experiments: Overview on high burnup spent fuel dissolution studies at FZK/INE (A. Loida), Results on the influence of hydrogen on spent fuel leaching (K. Spahiu), Leaching of spent UO 2 fuel under inert and reducing conditions (Y. Albinsson), Fuel corrosion investigation by electrochemical techniques (D. Wegen), A reanalysis of LWR spent fuel flow through dissolution tests (B. Hanson), U-bearing secondary phases formed during fuel corrosion (R. Finch), The near-field chemical conditions and spent fuel leaching (D. Cui), The release of radionuclides from spent fuel in bentonite block (S.S. Kim), Trace actinide behavior in altered spent fuel (E. Buck, B. Hanson); Session 4 - Radiolysis Issues: The effect of radiolysis on UO 2 dissolution determined from electrochemical experiments with 238 Pu doped UO 2 M. Stroess-Gascoyne (F. King, J.S. Betteridge, F. Garisto), doped UO 2 studies (V. Rondinella), Preliminary results of static and dynamic dissolution tests with α doped UO 2 in Boom clay conditions (K. Lemmens), Studies of the behavior of UO 2 / water interfaces under He 2+ beam (C. Corbel), Alpha and gamma radiolysis effects on UO 2 alteration in water (C. Jegou), Behavior of Pu-doped pellets in brines (M. Kelm), On the potential catalytic behavior of

  10. Reactivity and isotopic composition of spent PWR [pressurized-water-reactor] fuel as a function of initial enrichment, burnup, and cooling time

    International Nuclear Information System (INIS)

    Cerne, S.P.; Hermann, O.W.; Westfall, R.M.

    1987-10-01

    This study presents the reactivity loss of spent PWR fuel due to burnup in terms of the infinite lattice multiplications factor, k/sub ∞/. Calculations were performed using the SAS2 and CSAS1 control modules of the SCALE system. The k/sub ∞/ values calculated for all combinations of six enrichments, seven burnups, and five cooling times. The results are presented as a primary function of enrichment in both tabular and graphic form. An equation has been developed to estimate the tabulated values of k/sub ∞/'s by specifying enrichment, cooling time, and burnup. Atom densities for fresh fuel, and spent fuel at cooling times of 2, 10, and 20 years are included. 13 refs., 8 figs., 8 tabs

  11. Mineralogic and petrologic investigation of pre-test core samples from the spent fuel test-climax

    International Nuclear Information System (INIS)

    Ryerson, F.J.; Qualheim, B.J.

    1983-12-01

    Pre-test samples obtained from just inside the perimeter of the canister emplacement holes of the Spent Fuel Test-Climax have been characterized by petrographic and microanalytical techniques. The primary quartz monzonite has undergone various degrees of hydrothermal alteration as a result of natural processes. Alteration is most apparent on primary plagioclase and biotite. The most common secondary phases on plagioclase are muscovite and calcite, while the most common secondary phases on biotite are epidote and chlorite. The major alteration zones encountered are localized along filled fractures, i.e. veins. The thickness and mineralogy of the alteration zones can be correlated with the vein mineralogy, becoming wider and more complex mineralogically when the veins contain calcite. 7 references, 10 figures, 4 tables

  12. Soldiers for the virtual battlefield : Even at secondary school, Jan Paul van Waveren spent more time on computer games than on his homework, though he doesn't seem to have suffered from it

    NARCIS (Netherlands)

    Van Waveren, J.P.; Rothkrantz, L.; Jongeneel, C.

    2001-01-01

    Even at secondary school, Jan Paul van Waveren spent more time on computer games than on his homework,though he doesnt seem to have suffered from it. At university he spent some of his time linking up personal computers with his friends, trying to blast each other to virtual smithereens in a game of

  13. Emerging effortful control in toddlerhood: the role of infant orienting/regulation, maternal effortful control, and maternal time spent in caregiving activities.

    Science.gov (United States)

    Bridgett, David J; Gartstein, Maria A; Putnam, Samuel P; Lance, Kate Oddi; Iddins, Erin; Waits, Robin; Vanvleet, Jessica; Lee, Lindsay

    2011-02-01

    Latent growth modeling (LGM) was used to examine the contribution of changes in infant orienting/regulation (O/R) to the emergence of toddler effortful control (EC), the contributions of maternal EC to the development of infant O/R and the emergence of toddler EC, the influence of maternal time spent in caregiving activities on toddler EC and the slope of infant O/R, and the contribution of maternal EC to subsequent maternal time spent in caregiving activities. Mothers from 158 families completed a self-report measure of EC when their infants were 4 months of age, a measure of infant O/R when their infants were 4, 6, 8, 10, and 12 months of age, and a measure of toddler EC when their children reached 18 months of age. Information concerning maternal time spent in various interactive caregiving activities was collected when infants were 6 months old. Results indicated higher maternal EC predicted interindividual differences in the intercept (i.e., higher intercepts), but not slope, of infant O/R and that higher maternal EC, higher infant O/R intercept, and higher infant O/R slope contributed to higher toddler EC. Furthermore, higher maternal EC predicted greater maternal time spent in interactive caregiving activities with their infants and greater maternal time in interactive caregiving with infants also contributed to higher toddler EC after controlling for maternal EC. These findings contribute to the understanding of the influence of maternal EC, directly and through caregiving, on toddler EC. Additional implications as they are related to early developing regulatory aspects of temperament are discussed. Copyright © 2010 Elsevier Inc. All rights reserved.

  14. Objectively measured time spent sedentary is associated with insulin resistance independent of overall and central body fat in 9- to 10-year-old Portuguese children

    DEFF Research Database (Denmark)

    Sardinha, Luis B; Andersen, Lars Bo; Anderssen, Sigmund A

    2007-01-01

    OBJECTIVE: We examined the independent relationships between objectively measured physical activity and insulin resistance in Portuguese children. RESEARCH DESIGN AND METHODS: This is a school-based, cross-sectional study in 147 randomly selected girls (aged 9.8 +/- 0.3 years; 27.8 +/- 9.3% body...... fat) and 161 boys (aged 9.8 +/- 0.3 years; 22.0 +/- 9.2% body fat). Physical activity was assessed by the Actigraph accelerometer for 4 days and summarized as time spent sedentary (accelerometer counts ... (beta-coefficient = 0.001 [95% CI 0.0002-0.002]; P = 0.013). Time spent in moderate- and vigorous-intensity physical activity (-0.002 [-0.003 to -0.001]; P = 0.0009) and overall physical activity (-0.001 [-0.008 to 0.003]; P

  15. A summary of INSITE activities in tracking SKB's spent fuel repository site investigations from 2002-2009 and of advice provided to the regulatory authorities on the status of site understanding at the end of the surface-based investigations

    International Nuclear Information System (INIS)

    Chapman, Neil; Bath, Adrian; Geier, Joel; Ove Stephansson; Tiren, Sven; Tsang, Chin-Fu

    2010-11-01

    SSM and its predecessor SKI employed a team of earth scientists who followed and reviewed SKB's investigations of the potential spent nuclear fuel repository sites at Forsmark and Laxemar. This group was named INSITE (INdependent Site Investigation Tracking and Evaluation) and began its work in 2002 and completed its task with the review of the final versions SKB's site descriptive models, SDM-Site, in 2009. This report is a summary of INSITE's work over the eight-and-a-half year period of the site investigations and the lead-in and the wind-down to the work. It is intended to provide an outline and a record of how INSITE has worked and how its advice was generated and provided to SKI and, latterly, to SSM. Together with all the other documentation generated by INSITE, this report is intended to support the regulatory review of SKB's licence application for a spent nuclear fuel repository

  16. The associations between self-reported sleep duration and adolescent health outcomes: what is the role of time spent on Internet use?

    Science.gov (United States)

    Do, Young Kyung; Shin, Eunhae; Bautista, Mary Ann; Foo, Kelvin

    2013-02-01

    This study aimed to examine the associations of self-reported sleep duration with adolescent health outcomes, taking into account time spent on Internet use. We used data from the 2008-2009 Korea Youth Behavioral Risk Factor Survey, a cross-sectional online survey of middle and high school students aged 13-18years in South Korea (N=136,589) to examine the associations of self-reported sleep duration with four mental and physical health measures, e.g. self-report of depressive symptoms, suicidal ideation, weight status, and self-rated health. The binary logit and generalized ordered logit models controlled for time spent on Internet use for non-study purposes and other factors. Shorter self-reported sleep duration was associated with a higher likelihood of reporting depressive symptoms, suicidal ideation, and overweight or obese status, and a lower likelihood of reporting better self-rated health, even after accounting for time spent on Internet use. Excessive Internet use was found to be an independent risk factor for these outcomes. Among in-school adolescents in South Korea, shorter sleep duration and excessive Internet use are independently and additively associated with multiple indicators of adverse health status. Excessive Internet use may have not only direct adverse health consequences, but also have indirect negative effects through sleep deprivation. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. The effect of wheelchair propulsion style on changes in time spent in extreme wrist orientations after a bout of fatiguing propulsion.

    Science.gov (United States)

    Zukowski, Lisa A; Hass, Chris J; Shechtman, Orit; Christou, Evangelos A; Tillman, Mark D

    2017-10-01

    This study compared how wheelchair propulsion styles affect changes in percentage of time spent in extreme wrist orientations, which have been associated with median nerve injury, after a fatiguing bout of propulsion. Twenty novice, non-disabled adult males learned arcing (ARC) and semicircular (SEMI) propulsion styles and utilised each to perform a wheelchair fatigue protocol. ARC and SEMI did not significantly differ in terms of changes after the fatigue protocol in percentage of time spent in extreme flexion/extension or radial/ulnar deviation at the push phase beginning or end. A pattern was observed, although not significant, of greater increases in percentage of time spent in extreme wrist extension and ulnar deviation during the push phase beginning and ulnar deviation during the push phase end while utilising SEMI relative to ARC. This study evinces that individual differences are greater than observed changes in extreme wrist orientations for both propulsion styles. Practitioner Summary: How wheelchair propulsion styles change with fatigue in terms of extreme wrist orientations was examined. This study evinces that individual differences are greater than observed changes in extreme wrist orientations for both propulsion styles and point towards the need for future research on individual differences utilising propulsion styles.

  18. The spent fuel safety experiment

    International Nuclear Information System (INIS)

    Harmms, G.A.; Davis, F.J.; Ford, J.T.

    1995-01-01

    The Department of Energy is conducting an ongoing investigation of the consequences of taking fuel burnup into account in the design of spent fuel transportation packages. A series of experiments, collectively called the Spent Fuel Safety Experiment (SFSX), has been devised to provide integral benchmarks for testing computer-generated predictions of spent fuel behavior. A set of experiments is planned in which sections of unirradiated fuel rods are interchanged with similar sections of spent PWR fuel rods in a critical assembly. By determining the critical size of the arrays, one can obtain benchmark data for comparison with criticality safety calculations. The integral reactivity worth of the spent fuel can be assessed by comparing the measured delayed critical fuel loading with and without spent fuel. An analytical effort to model the experiments and anticipate the core loadings required to yield the delayed critical conditions runs in parallel with the experimental effort

  19. Time/motion observations and dose analysis of reactor loading, transportation, and dry unloading of an overweight truck spent fuel shipment

    International Nuclear Information System (INIS)

    Hostick, C.J.; Lavender, J.C.; Wakeman, B.H.

    1992-04-01

    This document presents observed activity durations and radiation dose analyses for an overweight truck shipment of pressurized water reactor (PWR) spent fuel from the Surry Power Station in Virginia to the Idaho National Engineering Laboratory. The shipment consisted of a TN-8L shipping cask carrying three 9-year-old PWR spent fuel assemblies. Handling times and dose analyses for at-reactor activities were completed by Virginia Electric and Power Company (Virginia Power) personnel. Observations of in-transit and unloading activities were made by Pacific Northwest Laboratory (PNL) personnel, who followed the shipment for approximately 2800 miles and observed cask unloading activities. In-transit dose estimates were calculated using dose rate maps provided by Virginia Power for a fully loaded TN-8L shipping cask. The dose analysis for the cask unloading operations is based on the observations of PNL personnel

  20. Time and dose assessment of barge shipment and at-reactor handling of a CASTOR V/21 spent fuel storage cask

    Energy Technology Data Exchange (ETDEWEB)

    Hostick, C.J. (Pacific Northwest Lab., Richland, WA (United States)); Lavender, J.C. (Westinghouse Hanford Co., Richland, WA (United States)); Wakeman, B.H. (Virginia Electric and Power Co., Richmond, VA (United States))

    1992-04-01

    This report contains the results of a time/motion analysis and a radiation dose assessment made during the receipt from barge transport and the loading of CAst iron cask for Storage and Transport Of Radioactive material (CASTOR) V/21 storage casks with spent nuclear fuel at the Surry Power Station in Virginia during 1987. The study was a cooperative effort between Pacific Northwest Laboratory (PNL) and Virginia Electric and Power Company (Virginia Power), and was funded by the US Department of Energy (DOE) Transportation Program Office. In this study, cask handling activities were tracked at the Surry Power Station, tracing the transfer of the empty spent fuel storage cask from an ocean-going vessel to a barge for river transport through the activities required to place the loaded storage cask at an at-reactor storage location.

  1. The geochemical immobilization of uranium in a spent fuel repository in the Canadian Shield: Evidence from natural analogue investigations

    International Nuclear Information System (INIS)

    Bottomley, D.J.

    1996-04-01

    Natural analogue studies of uranium ore deposits provide valuable information on the geochemical conditions that control the mobilization of uranium and associated radionuclides in groundwaters. At Cigar Lake in northern Saskatchewan, the Pocos de Caldas site in Brazil, and at Palmottu in Finland, groundwaters are sufficiently reducing to prevent significant oxidation of U +4 to the more soluble U +6 oxidation state. Despite being one of the richest uranium deposits in the world, uranium concentrations in the groundwaters around the Cigar Lake ore are less than 5 x 10 -8 M. Even under oxiding conditions uranium may not necessarily be highly mobilized by groundwaters. Studies of the relatively shallow uranium ore deposits in the Alligator Rivers region of Australia have shown that uranium transport by groundwater can be limited because of uranium sorption onto secondary iron oxides within the aquifer. However, studies at 'negative analgoue' sites indicate that where the host rocks contain low concentrations of reductants such as iron sulphides, strongly reducing conditions are not established and high concentrations of dissolved uranium can result, even in areas where uranium ore deposits are not known to occur. The release rate of radionuclides from a spent fuel repository will be strongly dependent on the redox conditions that are established following resaturation of the repository. Groundwater at depths of 500 m in a granitic pluton may not be sufficiently reducing to prevent oxidative dissolution of uranium or oxidation of associated radionuclides such as 99 Tc. Accordingly other shield rocks richer in reductants, such as greenstone belts, should be considered as potential host rocks for a repository or the repository should be constructed at depths closer to 1000 m in granitic rock where more reducing conditions are likely to prevail. Alternatively, addition of reductants to the waste containers may be feasible as a means of maintaining reducing conditions

  2. Premigration School Quality, Time Spent in the United States, and the Math Achievement of Immigrant High School Students.

    Science.gov (United States)

    Bozick, Robert; Malchiodi, Alessandro; Miller, Trey

    2016-10-01

    Using a nationally representative sample of 1,189 immigrant youth in American high schools, we examine whether the quality of education in their country of origin is related to post-migration math achievement in the 9th grade. To measure the quality of their education in the country of origin, we use country-specific average test scores from two international assessments: the Programme for International Student Assessment (PISA) and the Trends in International Mathematics and Science Study (TIMSS). We find that the average PISA or TIMSS scores for immigrant youth's country of origin are positively associated with their performance on the 9th grade post-migration math assessment. We also find that each year spent in the United States is positively associated with performance on the 9th grade post-migration math assessment, but this effect is strongest for immigrants from countries with low PISA/TIMSS scores.

  3. Experimental investigation of tunneling times using Bose-Einstein condensates

    International Nuclear Information System (INIS)

    Ciampini, Donatella; Arimondo, Ennio; Morsch, Oliver

    2011-01-01

    The time it takes a quantum system to complete a tunneling event (which in the case of cross-barrier tunneling can be viewed as the time spent in a classically forbidden area) is related to the time required for a state to evolve to an orthogonal state, and an observation, i.e., a quantum mechanical projection on a particular basis, is required to distinguish one state from another. We have performed time-resolved measurements of Landau-Zener tunneling of Bose-Einstein condensates in accelerated optical lattices, clearly resolving the steplike time dependence of the band populations. The use of different protocols enabled us to access the tunneling probability, in two different bases, namely, the adiabatic basis and the diabatic basis. The adiabatic basis corresponds to the eigenstates of the lattice, and the diabatic one to the free-particle momentum eigenstates. Our findings pave the way towards more quantitative studies of the tunneling time for LZ transitions, which are of current interest in the context of optimal quantum control and the quantum speed limit.

  4. Borehole radar measurements performed on preliminary investigation areas in Finland for final disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Carlsten, S.

    1991-05-01

    Borehole radar measurements with the RAMAC system have been performed in 24 boreholes distributed between the investigation areas Kuhmo Romuvaara, Hyrynsalmi Veitsivaara, Konginkangas Kivetty, Sievi Syyry, and Eurajoki Olkiluoto. The purpose of the borehole radar measurement program has been to investigate the bedrock in the vicinity of the boreholes in order to obtain information about geometry and extent of fracture zones, lithological contacts and other structures. The measurements have been performed as singlehole radar reflection measurements and Vertical Radar Profiling (VRP) measurements, using antennas with 22 MHz frequency range in both configurations. The total measured length in the singlehole radar reflection mode is 13304 meter and in the VRP mode 9200 meter. The VRP measurements are not presented in the report. Radar data from the singlehole reflection measurements are presented as grey scale radar maps after digital filtering with a bandpass filter and a moving average filter. Interpreted zones from the singlehole radar measurements are presented in tables for each borehole. It has been possible to study structures at distances of more than 110 meter from the borehole

  5. Effect of exposure to greater active videogame variety on time spent in moderate- to vigorous-intensity physical activity.

    Science.gov (United States)

    Raynor, Hollie A; Cardoso, Chelsi; Bond, Dale S

    2016-07-01

    This investigation examined whether exposure to greater active videogame variety increases moderate- to vigorous-intensity physical activity (MVPA). Twenty-three participants (age=22.7±4.2yrs; body mass index=23.5±3.0kg/m(2); self-reported MVPA=298.7±116.7min/wk; 62.2% female; 73.9% Caucasian) participated in VARIETY (4 different active videogames during 4, 15-min bouts) and NON-VARIETY (only 1 active videogame during 4, 15-min bouts) counterbalanced sessions. VARIETY provided a different active videogame in each bout. NON-VARIETY provided participants their most highly liked active videogame in each bout. The Sensewear Mini Armband objectively assessed MVPA. For MVPA minutes, a session×bout (p<0.05) interaction occurred. In NON-VARIETY, bouts 2, 3, and 4 had significantly (p<0.05) fewer minutes than bout 1, with no decrease occurring in VARIETY. In bout 4, VARIETY had significantly (p<0.05) more minutes than NON-VARIETY. A main effect of session (p<0.05) occurred for MVPA minutes and energy expenditure, with VARIETY achieving greater amounts (31.8±14.3min vs. 27.6±16.9min; 186.1±96.8kcal vs. 171.2±102.8kcal). Exposure to greater activity variety within a session increased MVPA. Future research should examine exposure to a variety of activities over a longer time frame with participants of differing lifestyles in free-living environments. Copyright © 2016. Published by Elsevier Inc.

  6. Off-Stream Watering Systems and Partial Barriers as a Strategy to Maximize Cattle Production and Minimize Time Spent in the Riparian Area

    Directory of Open Access Journals (Sweden)

    Ashley A. Rawluk

    2014-10-01

    Full Text Available A study was conducted in 2009 at two locations in Manitoba (Killarney and Souris, Canada to determine the impact of off-stream waterers (OSW with or without natural barriers on (i amount of time cattle spent in the 10 m buffer created within the riparian area, referred to as the riparian polygon (RP, (ii watering location (OSW or stream, and (iii animal performance measured as weight gain. This study was divided into three 28-day periods over the grazing season. At each location, the pasture—which ranged from 21.0 ha to 39.2 ha in size—was divided into three treatments: no OSW nor barriers (1CONT, OSW with barriers along the stream bank to deter cattle from watering at the stream (2BARR, and OSW without barriers (3NOBARR. Cattle in 2BARR spent less time in the RP in Periods 1 (p = 0.0002, 2 (p = 0.1116, and 3 (p < 0.0001 at the Killarney site compared to cattle in 3NOBARR at the same site. Cattle in 2BARR at the Souris site spent more time in the RP in Period 1 (p < 0.0001 and less time in Period 2 (p = 0.0002 compared to cattle in 3NOBARR. Cattle did use the OSW, but not exclusively, as watering at the stream was still observed. The observed inconsistency in the effectiveness of the natural barriers on deterring cattle from the riparian area between periods and locations may be partly attributable to the environmental conditions present during this field trial as well as difference in pasture size and the ability of the established barriers to deter cattle from using the stream as a water source. Treatment had no significant effect (p > 0.05 on cow and calf weights averaged over the summer period. These results indicate that the presence of an OSW does not create significant differences in animal performance when used in extensive pasture scenarios such as those studied within the present study. Whereas the barriers did not consistently discourage watering at the stream, the results provide some indication of the efficacy of the OSW as well

  7. ENVI Model Development for Korean Nuclear Spent Fuel Options Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Sunyoung; Jeong, Yon Hong; Han, Jae-Jun; Lee, Aeri; Hwang, Yong-Soo [Korea Institute of Nuclear Nonproliferation and Control, Daejeon (Korea, Republic of)

    2015-10-15

    The disposal facility of the spent nuclear fuel will be operated from 2051. This paper presents the ENVI code developed by GoldSim Software to simulate options for managing spent nuclear fuel (SNF) in South Korea. The ENVI is a simulator to allow decision-makers to assist to evaluate the performance for spent nuclear fuel management. The multiple options for managing the spent nuclear fuel including the storage and transportation are investigated into interim storage, permanent disposal in geological repositories and overseas and domestic reprocessing. The ENVI code uses the GoldSim software to simulate the logistics of the associated activities. The result by the ENVI model not only produces the total cost to compare among the multiple options but also predict the sizes and timings of different facilities required. In order to decide the policy for spent nuclear management this purpose of this paper is to draw the optimum management plan to solve the nuclear spent fuel issue in the economical aspects. This paper is focused on the development of the ENVI's logic and calculations to simulate four options(No Reprocessing, Overseas Reprocessing, Domestic Reprocessing, and Overseas and Domestic Reprocessing) for managing the spent nuclear fuel in South Korea. The time history of the spent nuclear fuel produced from both the existing and future NPP's can be predicted, based on the Goldsim software made available very user friendly model. The simulation result will be used to suggest the strategic plans for the spent nuclear fuel management.

  8. ENVI Model Development for Korean Nuclear Spent Fuel Options Analysis

    International Nuclear Information System (INIS)

    Chang, Sunyoung; Jeong, Yon Hong; Han, Jae-Jun; Lee, Aeri; Hwang, Yong-Soo

    2015-01-01

    The disposal facility of the spent nuclear fuel will be operated from 2051. This paper presents the ENVI code developed by GoldSim Software to simulate options for managing spent nuclear fuel (SNF) in South Korea. The ENVI is a simulator to allow decision-makers to assist to evaluate the performance for spent nuclear fuel management. The multiple options for managing the spent nuclear fuel including the storage and transportation are investigated into interim storage, permanent disposal in geological repositories and overseas and domestic reprocessing. The ENVI code uses the GoldSim software to simulate the logistics of the associated activities. The result by the ENVI model not only produces the total cost to compare among the multiple options but also predict the sizes and timings of different facilities required. In order to decide the policy for spent nuclear management this purpose of this paper is to draw the optimum management plan to solve the nuclear spent fuel issue in the economical aspects. This paper is focused on the development of the ENVI's logic and calculations to simulate four options(No Reprocessing, Overseas Reprocessing, Domestic Reprocessing, and Overseas and Domestic Reprocessing) for managing the spent nuclear fuel in South Korea. The time history of the spent nuclear fuel produced from both the existing and future NPP's can be predicted, based on the Goldsim software made available very user friendly model. The simulation result will be used to suggest the strategic plans for the spent nuclear fuel management

  9. Correlates of time spent walking and cycling to and from work: baseline results from the commuting and health in Cambridge study

    Directory of Open Access Journals (Sweden)

    Panter Jenna

    2011-11-01

    Full Text Available Abstract Purpose Environmental perceptions and psychological measures appear to be associated with walking and cycling behaviour; however, their influence is still unclear. We assessed these associations using baseline data from a quasi-experimental cohort study of the effects of major transport infrastructural developments in Cambridge, UK. Methods Postal surveys were sent to adults who travel to work in Cambridge (n = 1582. Questions asked about travel modes and time spent travelling to and from work in the last week, perceptions of the route, psychological measures regarding car use and socio-demographic characteristics. Participants were classified into one of two categories according to time spent walking for commuting ('no walking' or 'some walking' and one of three categories for cycling ('no cycling', '1-149 min/wk' and ' ≥ 150 min/wk'. Results Of the 1164 respondents (68% female, mean (SD age: 42.3 (11.4 years 30% reported any walking and 53% reported any cycling to or from work. In multiple regression models, short distance to work and not having access to a car showed strong positive associations with both walking and cycling. Furthermore, those who reported that it was pleasant to walk were more likely to walk to or from work (OR = 4.18, 95% CI 3.02 to 5.78 and those who reported that it was convenient to cycle on the route between home and work were more likely to do so (1-149 min/wk: OR = 4.60, 95% CI 2.88 to 7.34; ≥ 150 min/wk: OR = 3.14, 95% CI 2.11 to 4.66. Positive attitudes in favour of car use were positively associated with time spent walking to or from work but negatively associated with cycling to or from work. Strong perceived behavioural control for car use was negatively associated with walking. Conclusions In this relatively affluent sample of commuters, a range of individual and household characteristics, perceptions of the route environment and psychological measures relating to car use were associated with

  10. Spent fuel dissolution mechanisms

    International Nuclear Information System (INIS)

    Ollila, K.

    1993-11-01

    This study is a literature survey on the dissolution mechanisms of spent fuel under disposal conditions. First, the effects of radiolysis products on the oxidative dissolution mechanisms and rates of UO 2 are discussed. These effects have mainly been investigated by using electrochemical methods. Then the release mechanisms of soluble radionuclides and the dissolution of the UO 2 matrix including the actinides, are treated. Experimental methods have been developed for measuring the grain-boundary inventories of radionuclides. The behaviour of cesium, strontium and technetium in leaching tests shows different trends. Comparison of spent fuel leaching data strongly suggests that the release of 90 Sr into the leachant can be used as a measure of the oxidation/dissolution of the fuel matrix. Approaches to the modelling UO 2 , dissolution are briefly discussed in the next chapter. Lastly, the use of natural material, uraninite, in the evaluation of the long-term performance of spent fuel is discussed. (orig.). (81 ref., 37 figs., 8 tabs.)

  11. Time spent in primary care for hip osteoarthritis patients once the diagnosis is set : a prospective observational study

    NARCIS (Netherlands)

    Paans, Nienke; van der Veen, Willem Jan; van der Meer, Klaas; Bulstra, Sjoerd K.; van den Akker-Scheek, Inge; Stevens, Martin

    2011-01-01

    Background: Previous research on time to referral to orthopaedic surgery has predominantly used hip complaints as starting point instead of the moment the diagnosis of osteoarthritis (OA) of the hip is established, therefore little is known about the length of time a patient diagnosed with hip OA

  12. Behaviour of spent fuel assemblies during extended storage

    International Nuclear Information System (INIS)

    1987-04-01

    This report is the final report of the IAEA Co-ordinated Research Programme on Behaviour of Spent Fuel Assemblies During Extended Storage (BEFAST, Phase I, 1981-86). It contains the results on wet and dry spent fuel storage technologies obtained from 11 institutes (10 countries: Austria, Canada, Czechoslovakia, Finland, German Democratic Republic, Hungary, Japan, Sweden, USA and USSR) participating in the BEFAST CRP during the time period 1981-86. Names of participating institutes and chief investigators are given. The interim spent fuel storage has been recognized as an important independent step in the nuclear fuel cycle. Due to the delay in commercial reprocessing of spent fuel in some cases it should be stored up to 30-50 years or more before reprocessing or final disposal. This programme was evaluated by all its participants and observers as very important and helpful for the nuclear community and it was decided to continue it further (1986-91) as BEFAST, Phase II

  13. Investigation of thermally sensitised stainless steels as analogues for spent AGR fuel cladding to test a corrosion inhibitor for intergranular stress corrosion cracking

    Science.gov (United States)

    Whillock, Guy O. H.; Hands, Brian J.; Majchrowski, Tom P.; Hambley, David I.

    2018-01-01

    A small proportion of irradiated Advanced Gas-cooled Reactor (AGR) fuel cladding can be susceptible to intergranular stress corrosion cracking (IGSCC) when stored in pond water containing low chloride concentrations, but corrosion is known to be prevented by an inhibitor at the storage temperatures that have applied so far. It may be necessary in the future to increase the storage temperature by up to ∼20 °C and to demonstrate the impact of higher temperatures for safety case purposes. Accordingly, corrosion testing is needed to establish the effect of temperature increases on the efficacy of the inhibitor. This paper presents the results of studies carried out on thermally sensitised 304 and 20Cr-25Ni-Nb stainless steels, investigating their grain boundary compositions and their IGSCC behaviour over a range of test temperatures (30-60 °C) and chloride concentrations (0.3-10 mg/L). Monitoring of crack initiation and propagation is presented along with preliminary results as to the effect of the corrosion inhibitor. 304 stainless steel aged for 72 h at 600 °C provided a close match to the known pond storage corrosion behaviour of spent AGR fuel cladding.

  14. A real-time data acquisition and processing system for the analytical laboratory automation of a HTR spent fuel reprocessing facility

    International Nuclear Information System (INIS)

    Watzlawik, K.H.

    1979-12-01

    A real-time data acquisition and processing system for the analytical laboratory of an experimental HTR spent fuel reprocessing facility is presented. The on-line open-loop system combines in-line and off-line analytical measurement procedures including data acquisition and evaluation as well as analytical laboratory organisation under the control of a computer-supported laboratory automation system. In-line measurements are performed for density, volume and temperature in process tanks and registration of samples for off-line measurements. Off-line computer-coupled experiments are potentiometric titration, gas chromatography and X-ray fluorescence analysis. Organisational sections like sample registration, magazining, distribution and identification, multiple data assignment and especially calibrations of analytical devices are performed by the data processing system. (orig.) [de

  15. Time spent in primary care for hip osteoarthritis patients once the diagnosis is set: a prospective observational study

    Directory of Open Access Journals (Sweden)

    van den Akker-Scheek Inge

    2011-06-01

    Full Text Available Abstract Background Previous research on time to referral to orthopaedic surgery has predominantly used hip complaints as starting point instead of the moment the diagnosis of osteoarthritis (OA of the hip is established, therefore little is known about the length of time a patient diagnosed with hip OA stays under the care of a general practitioner (GP. No knowledge on factors of influence on this time period is available either. Aim of this study was thus to determine the time an incident hip OA patient stays in the care of a GP until referral to an orthopaedic department. Influencing factors were also analyzed. Methods A prospective observational study was conducted based on data over a 10-year period from a general practice-based registration network (17 GPs, > 30,000 patients registered yearly. Patients with the diagnosis of hip OA were included. A survival analysis was used to determine time until referral to an orthopaedic department, and to determine factors of influence on this time. Results Of 391 patients diagnosed with hip OA, 121 (31% were referred; average survival time until referral was 82.0 months (95% CI 76.6-87.5. Less contact with the GP for hip complaints before the diagnosis of hip OA was established resulted in a decreased time to referral. Conclusions The results of this study show that patients with hip OA were under the care of a general practitioner, and thus in primary care, for a considerable amount of time once the diagnosis of hip OA was established.

  16. Off-Stream Watering Systems and Partial Barriers as a Strategy to Maximize Cattle Production and Minimize Time Spent in the Riparian Area.

    Science.gov (United States)

    Rawluk, Ashley A; Crow, Gary; Legesse, Getahun; Veira, Douglas M; Bullock, Paul R; González, Luciano A; Dubois, Melanie; Ominski, Kim H

    2014-10-29

    A study was conducted in 2009 at two locations in Manitoba (Killarney and Souris), Canada to determine the impact of off-stream waterers (OSW) with or without natural barriers on (i) amount of time cattle spent in the 10 m buffer created within the riparian area, referred to as the riparian polygon (RP), (ii) watering location (OSW or stream), and (iii) animal performance measured as weight gain. This study was divided into three 28-day periods over the grazing season. At each location, the pasture-which ranged from 21.0 ha to 39.2 ha in size-was divided into three treatments: no OSW nor barriers (1CONT), OSW with barriers along the stream bank to deter cattle from watering at the stream (2BARR), and OSW without barriers (3NOBARR). Cattle in 2BARR spent less time in the RP in Periods 1 (p = 0.0002), 2 (p = 0.1116), and 3 (p natural barriers on deterring cattle from the riparian area between periods and locations may be partly attributable to the environmental conditions present during this field trial as well as difference in pasture size and the ability of the established barriers to deter cattle from using the stream as a water source. Treatment had no significant effect (p > 0.05) on cow and calf weights averaged over the summer period. These results indicate that the presence of an OSW does not create significant differences in animal performance when used in extensive pasture scenarios such as those studied within the present study. Whereas the barriers did not consistently discourage watering at the stream, the results provide some indication of the efficacy of the OSW as well as the natural barriers on deterring cattle from the riparian area.

  17. Surveillance instrumentation for spent-fuel safeguards

    International Nuclear Information System (INIS)

    McKenzie, J.M.; Holmes, J.P.; Gillman, L.K.; Schmitz, J.A.; McDaniel, P.J.

    1978-01-01

    The movement, in a facility, of spent reactor fuel may be tracked using simple instrumentation together with a real time unfolding algorithm. Experimental measurements, from multiple radiation monitors and crane weight and position monitors, were obtained during spent fuel movements at the G.E. Morris Spent-Fuel Storage Facility. These data and a preliminary version of an unfolding algorithm were used to estimate the position of the centroid and the magnitude of the spent fuel radiation source. Spatial location was estimated to +-1.5 m and source magnitude to +-10% of their true values. Application of this surveillance instrumentation to spent-fuel safeguards is discussed

  18. Reprocessing of spent nuclear fuel

    International Nuclear Information System (INIS)

    Schmitt, D.

    1985-01-01

    How should the decision in favour of reprocessing and against alternative waste management concepts be judged from an economic standpoint. Reprocessing is not imperative neither for resource-economic reasons nor for nuclear energy strategy reasons. On the contrary, the development of an ultimate storage concept representing a real alternative promising to close, within a short period of time, the nuclear fuel cycle at low cost. At least, this is the result of an extensive economic efficiency study recently submitted by the Energy Economics Institute which investigated all waste management concepts relevant for the Federal Republic of Germany in the long run, i.e. direct ultimate storage of spent fuel elements (''Other waste disposal technologies'' - AE) as well as reprocessing of spent fuel elements where re-usable plutonium and uranium are recovered and radioactive waste goes to ultimate storage (''Integrated disposal'' - IE). Despite such fairly evident results, the government of the Federal Republic of Germany has favoured the construction of a reprocessing plant. From an economic point of view there is no final answer to the question whether or not the argumentation is sufficient to justify the decision to construct a reprocessing plant. This is true for both the question of technical feasibility and issues of overriding significance of a political nature. (orig./HSCH) [de

  19. Intermodal transportation of spent fuel

    International Nuclear Information System (INIS)

    Elder, H.K.

    1983-09-01

    Concepts for transportation of spent fuel in rail casks from nuclear power plant sites with no rail service are under consideration by the US Department of Energy in the Commercial Spent Fuel Management program at the Pacific Northwest Laboratory. This report identifies and evaluates three alternative systems for intermodal transfer of spent fuel: heavy-haul truck to rail, barge to rail, and barge to heavy-haul truck. This report concludes that, with some modifications and provisions for new equipment, existing rail and marine systems can provide a transportation base for the intermodal transfer of spent fuel to federal interim storage facilities. Some needed land transportation support and loading and unloading equipment does not currently exist. There are insufficient shipping casks available at this time, but the industrial capability to meet projected needs appears adequate

  20. The Cell Cycle: An Activity Using Paper Plates to Represent Time Spent in Phases of the Cell Cycle

    Science.gov (United States)

    Scherer, Yvette D.

    2014-01-01

    In this activity, students are given the opportunity to combine skills in math and geometry for a biology lesson in the cell cycle. Students utilize the data they collect and analyze from an online onion-root-tip activity to create a paper-plate time clock representing a 24-hour cell cycle. By dividing the paper plate into appropriate phases of…

  1. Time Spent by Breast Imaging Radiologists to Perform Value-Added Activities at an Academic Cancer Center.

    Science.gov (United States)

    Collado-Mesa, Fernando; Klevos, Geetika; Arheart, Kristopher; Banks, James; Yepes, Monica; Net, Jose

    2017-04-01

    Health care reform in the United States has generated a paradigm shift in the practice of radiology aimed at increasing the degree of patient-centered care. We conducted a study to quantify the amount of time breast imaging radiologists spend on value-added activities at an academic comprehensive cancer center located in Miami, Florida, and accredited by the American College of Radiology as a Breast Imaging Center of Excellence. A prospective, observational study was conducted during a period of 20 consecutive workdays. Three participating breast imaging radiologists maintained a real-time log of each activity performed. A generalized linear model was used to perform a 1-way analysis of variance. An alpha level of .05 was used to determine statistical significance. The average daily time dedicated to these activities was 92.1 minutes (range, 56.4-132.2). The amount of time significantly differed among breast imaging radiologists and correlated with their assigned daily role (P value-added activities to help improve patients' experience across the continuity of their care. We propose that similar studies be conducted at other institutions to better assess the magnitude of this finding across different breast imaging care settings.

  2. Time spent in outdoor activities in relation to myopia prevention and control: a meta-analysis and systematic review.

    Science.gov (United States)

    Xiong, Shuyu; Sankaridurg, Padmaja; Naduvilath, Thomas; Zang, Jiajie; Zou, Haidong; Zhu, Jianfeng; Lv, Minzhi; He, Xiangui; Xu, Xun

    2017-09-01

    Outdoor time is considered to reduce the risk of developing myopia. The purpose is to evaluate the evidence for association between time outdoors and (1) risk of onset of myopia (incident/prevalent myopia); (2) risk of a myopic shift in refractive error and c) risk of progression in myopes only. A systematic review followed by a meta-analysis and a dose-response analysis of relevant evidence from literature was conducted. PubMed, EMBASE and the Cochrane Library were searched for relevant papers. Of the 51 articles with relevant data, 25 were included in the meta-analysis and dose-response analysis. Twenty-three of the 25 articles involved children. Risk ratio (RR) for binary variables and weighted mean difference (WMD) for continuous variables were conducted. Mantel-Haenszel random-effects model was used to pool the data for meta-analysis. Statistical heterogeneity was assessed using the I 2 test with I 2  ≥ 50% considered to indicate high heterogeneity. Additionally, subgroup analyses (based on participant's age, prevalence of myopia and study type) and sensitivity analyses were conducted. A significant protective effect of outdoor time was found for incident myopia (clinical trials: risk ratio (RR) = 0.536, 95% confidence interval (CI) = 0.338 to 0.850; longitudinal cohort studies: RR = 0.574, 95% CI = 0.395 to 0.834) and prevalent myopia (cross-sectional studies: OR = 0.964, 95% CI = 0.945 to 0.982). With dose-response analysis, an inverse nonlinear relationship was found with increased time outdoors reducing the risk of incident myopia. Also, pooled results from clinical trials indicated that when outdoor time was used as an intervention, there was a reduced myopic shift of -0.30 D (in both myopes and nonmyopes) compared with the control group (WMD = -0.30, 95% CI = -0.18 to -0.41) after 3 years of follow-up. However, when only myopes were considered, dose-response analysis did not find a relationship between time outdoors and myopic

  3. How passion and impulsivity influence a player's choice of videogame, intensity of playing and time spent playing

    OpenAIRE

    Puerta-Cortés, Diana Ximena; Panova, Tayana; Carbonell, Xavier; Chamarro, Andrés

    2016-01-01

    Videogames have received much attention in addiction research due to their popularity and frequent use. However, few studies have addressed the effect of passion and impulsivity in gamers. Therefore, the aim of the current study was to examine the influence of passion and impulsivity on the intensity of play, playing time, and choice of Massive Multiplayer Online Role Play Game (MMORPG) vs. non-MMORPG. A sample of 630 university students (40.7% Colombian, 59.3% Spanish) responded ...

  4. Time spent studying on a pre-registration nursing programme module: an exploratory study and implications for regulation.

    Science.gov (United States)

    Snelling, Paul C; Lipscomb, Martin; Lockyer, Lesley; Yates, Sue; Young, Pat

    2010-11-01

    European Union (EU) regulations require that university programmes are of specified duration. Additional EU regulations apply specifically to university based nurse education, enacted in the UK by the Nursing and Midwifery Council (NMC). However, little is known about how much time student nurses spend on their studies. In this exploratory study, students undertaking a single module in the pre-registration diploma programme at an English university were asked to keep a log of learning activity for the duration of the module. Twenty-six students completed the log. These students achieved higher grades and attended more lectures than the average for the module. The mean study time was 128.4 h against a regulatory assumption that the module should take 200 h. More than half of the 26 students undertook paid work during the module run, though this work was not associated with poorer performance. Problems in regulation for course duration are discussed and it is suggested that undertaking a 4600 h course in 3 years is problematic. More research is required so that patterns of study can be better understood and student centred programmes meeting regulatory requirements developed. Copyright © 2010 Elsevier Ltd. All rights reserved.

  5. Investigations of possibilities to dispose of spent nuclear fuel in Lithuania: a model case. Volume 2, Concept of Repository in Crystalline Rocks

    International Nuclear Information System (INIS)

    Motiejunas, S.; Poskas, P.

    2005-01-01

    The aim is to present the generic repository concept in crystalline rocks in Lithuania and cost assessment of the disposal of spent nuclear fuel and long-lived intermediate level waste in this repository. Due to limited budget of this project the repository concept development for Lithuania was based mostly on the experience of foreign countries. In this Volume a review of the existing information on disposal concept in crystalline rocks from various countries is presented. Described repository concept for crystalline rocks in Lithuania covers repository layout, backfill, canister, construction materials and auxiliary buildings. Costs calculations for disposal of spent nuclear fuel and long-lived intermediate-level wastes from Ignalina NPP are presented too. Thermal, criticality and other important disposal evaluations for RBMK-1500 spent nuclear fuel emplaced in copper canister were performed and described

  6. Ecosystem description of a drainage area - a strategy in biosphere descriptions during site investigations for a repository of spent nuclear fuel

    International Nuclear Information System (INIS)

    Lindborg, T.; Lofgren, A.

    2004-01-01

    During the next few years the Swedish Nuclear Fuel and Waste Management Co. (SKB) performs site investigations at two sites in Sweden for a future repository of spent nuclear fuel. Novel methods based on systems and landscape ecology are developed to understand and model the radionuclide flow in the biosphere using site specific data for a safety assessment. This work describes the strategy for development of a descriptive ecosystem model for the surface ecosystem. The site description is needed to: a) perform a safety assessment that describes and analyzes different scenarios for radionuclide releases into the ecosystem and possible pathways for dispersal or accumulation radionuclides in the ecosystem, b) detect changes caused by the construction of a repository, c) establish a baseline for detecting long-term effects of the repository. The description adopts a site-specific approach focusing on the quantification of the properties that will constitute the descriptive model. The aim is also to present the methodology for determining the properties, to describe the development of the framework for the descriptive ecosystem models by integrating use of different properties, and finally, to present vital data from other site descriptive models such as those for geology or hydrogeology. The safety assessment will use an approach, among other methods, where transport and accumulation of radionuclides will be modelled by quantifying biogeochemical pathways of matter. The descriptive ecosystem model applied to the site was therefore built to describe and quantify processes affecting i.e. turnover of matter in a drainage area. The conclusions from applying this approach was that by have estimating the flow of matter the ecological and physical constrains on the system reduces the potential variations in outcome of future states of the ecosystem and thus also reduces the uncertainties in estimating radionuclide flow and consequences to humans and the environment. (author)

  7. Medical documentation: part of the solution, or part of the problem? A narrative review of the literature on the time spent on and value of medical documentation.

    Science.gov (United States)

    Clynch, Neil; Kellett, John

    2015-04-01

    Even though it takes up such a large part of all clinicians' working day the medical literature on documentation and its value is sparse. Medline searches combining the terms medical records, documentation, time, and value or efficacy or benefit yielded only 147 articles. This review is based on the relevant articles selected from this search and additional studies gathered from the personal experience of the authors and their colleagues. Documentation now occupies a quarter to half of doctors' time yet much of the information collected is of dubious or unproven value. Most medical records departments still use the traditional paper chart, and there is considerable debate on the benefits of electronic medical records (EMRs). Although EMRs contains a lot more information than a paper record clinicians do not find it easy to getting useful information out of them. Unlike the paper chart narrative is difficult to enter into most EMRs so that they do not adequately communicate the patient's "story" to clinicians. Recent innovations have the potential to address these issues. Although documentation is widespread throughout the health care industry there has been almost no formal research into its value, on how to enhance its value, or on whether the time spent on it has negative effects on patient care. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  8. Eye movements and serial memory for visual-spatial information: does time spent fixating contribute to recall?

    Science.gov (United States)

    Saint-Aubin, Jean; Tremblay, Sébastien; Jalbert, Annie

    2007-01-01

    This research investigated the nature of encoding and its contribution to serial recall for visual-spatial information. In order to do so, we examined the relationship between fixation duration and recall performance. Using the dot task--a series of seven dots spatially distributed on a monitor screen is presented sequentially for immediate recall--performance and eye-tracking data were recorded during the presentation of the to-be-remembered items. When participants were free to move their eyes at their will, both fixation durations and probability of correct recall decreased as a function of serial position. Furthermore, imposing constant durations of fixation across all serial positions had a beneficial impact (though relatively small) on item but not order recall. Great care was taken to isolate the effect of fixation duration from that of presentation duration. Although eye movement at encoding contributes to immediate memory, it is not decisive in shaping serial recall performance. Our results also provide further evidence that the distinction between item and order information, well-established in the verbal domain, extends to visual-spatial information.

  9. Investigating the distribution of the value of travel time savings

    DEFF Research Database (Denmark)

    Fosgerau, Mogens

    2006-01-01

    The distribution of the value of travel time savings (VTTS) is investigated employing various nonparametric techniques to a large dataset originating from a stated choice experiment. The data contain choices between a fast and more expensive alternative and a slow and less expensive alternative....... Increasing the implicit price of time leads to an increased share of respondents who decline to pay to save time. But a significant proportion of respondents, 13%, remain willing to pay to save time at the highest price of time in the design. This means that the right tail of the VTTS distribution...

  10. Transportation of spent nuclear fuels

    International Nuclear Information System (INIS)

    Meguro, Toshiichi

    1976-01-01

    The spent nuclear fuel taken out of reactors is cooled in the cooling pool in each power station for a definite time, then transported to a reprocessing plant. At present, there is no reprocessing plant in Japan, therefore the spent nuclear fuel is shipped abroad. In this paper, the experiences and the present situation in Japan are described on the transport of the spent nuclear fuel from light water reactors, centering around the works in Tsuruga Power Station, Japan Atomic Power Co. The spent nuclear fuel in Tsuruga Power Station was first transported in Apr. 1973, and since then, about 36 tons were shipped to Britain by 5 times of transport. The reprocessing plant in Japan is expected to start operation in Apr. 1977, accordingly the spent nuclear fuel used for the trial will be transported in Japan in the latter half of this year. Among the permission and approval required for the transport of spent nuclear fuel, the acquisition of the certificate for transport casks and the approval of land and sea transports are main tasks. The relevant laws are the law concerning the regulations of nuclear raw material, nuclear fuel and reactors and the law concerning the safety of ships. The casks used in Tsuruga Power Station and EXL III type, and the charging of spent nuclear fuel, the decontamination of the casks, the leak test, land transport with a self-running vehicle, loading on board an exclusive carrier and sea transport are briefly explained. The casks and the ship for domestic transport are being prepared. (Kato, I.)

  11. Modeling the optimal management of spent nuclear fuel

    International Nuclear Information System (INIS)

    Nachlas, J.A.; Kurstedt, H.A. Jr.; Swindle, D.W. Jr.; Korcz, K.O.

    1977-01-01

    Recent governmental policy decisions dictate that strategies for managing spent nuclear fuel be developed. Two models are constructed to investigate the optimum residence time and the optimal inventory withdrawal policy for fuel material that presently must be stored. The mutual utility of the models is demonstrated through reference case application

  12. Spent fuel transportation problems

    International Nuclear Information System (INIS)

    Kondrat'ev, A.N.; Kosarev, Yu.A.; Yulikov, E.A.

    1977-01-01

    In this paper, problems of transportation of nuclear spent fuel to reprocessing plants are discussed. The solutions proposed are directed toward the achievement of the transportation as economic and safe as possible. The increase of the nuclear power plants number in the USSR and the great distances between these plants and the reprocessing plants involve an intensification of the spent fuel transportation. Higher burnup and holdup time reduction cause the necessity of more bulky casks. In this connection, the economic problems become still more important. One of the ways of the problem solution is the development of rational and cheap cask designs. Also, the enforcement in the world of the environmental and personnel health protection requires to increase the transportation reliability and safety. The paper summarizes safe transportation rules with clarifying the following questions: the increase of the transport unit quantity of the spent fuel; rational shipment organization that minimizes vehicle turnover cycle duration; development of the reliable calculation methods to determine strength, thermal conditions and nuclear safety of transport packaging as applied to the vehicles of high capacity; maximum unification of vehicles, calculation methods and documents; and cask testing on models and in pilot scale on specific test rigs to assure that they meet the international safe fuel shipment rules. Besides, some considerations on the choice and use of structural materials for casks are given, and problems of manufacturing such casks from uranium and lead are considered, as well as problems of the development of fireproof shells, control instrumentation, vehicles decontamination, etc. All the problems are considered from the point of view of normal and accidental shipment conditions. Conclusions are presented [ru

  13. The velocity dependent dissolution of spent nuclear fuel in a geologic repository

    International Nuclear Information System (INIS)

    Nutt, W.M.

    1990-02-01

    A model describing the dissolution of fission products and transuranic isotopes from spent nuclear fuel into flowing ground water has been developed. This model is divided into two parts. The first part of the model calculates the temperature within a consolidated spent fuel waste form at a given time and ground water velocity. This model was used to investigate whether water flowing at rates representative of a geological repository located at Yucca Mountain, Nevada, will cool a wasteform consisting of consolidated spent nuclear fuel pins. Time and velocity dependent temperature profiles were generated. These profiles were input into the second model, which calculates the dissolution rate of waste isotopes from a spent fuel pin. Two dissolution limiting processes were modeled; the processes are dissolution limited by the solubility limit of an isotopes in the ground water, and dissolution limited by the diffusion of waste isotopes from the interior of a spent fuel pin to the surface where dissolution can occur

  14. An Investigation of Time Distribution of Pre-Service Teachers while Interning

    Science.gov (United States)

    Torres, Robert M.; Ulmer, Jonathan D.

    2007-01-01

    Student teaching is the culminating experience of most teacher preparation programs. Student teaching gives the prospective teacher the opportunity to join the worlds of theory and practice and to develop individual teaching talents. Long hours are regularly spent in several areas. This study sought to investigate how student teachers distribute…

  15. LSDS Development for Isotopic Fissile Assay in Spent Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Deok; Park, Chang Je; Park, Geun Il; Lee, Jung Won; Song, Kee Chan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-07-01

    As an option to reduce a spent fuel and reuse an existing fissile material in spent fuel, sodium fast reactor SFR program linked with pyro-processing is under development in KAERI. A uranium-TRU mixture through a pyro-process is used to fabricate SFR fuel. An assay of isotopic fissile content plays an important role in an optimum design of storage site and reuse of fissile materials of spent fuel. Lead slowing down spectrometer LSDS is being developed in KAERI to analyze isotopic fissile material content. LSDS has several features: direct fissile assay, near real time fissile assay, no influence from radiation background, fissile isotopic assay and applicable to spent fuel and recycled fuel. Based on the designed geometry, neutron energy resolution was investigated. The neutron energy spectrum was analyzed as well. Spent fuel emits large number of neutrons by spontaneous fission. Neutron generator must overcome the neutron background to get the pure fission signals from fissile materials. Neutron generator is planned to have compact system with one section electron linac which is easy maintenance, less cost and high neutron yield. The LSD has the power to resolve the fission characteristics from each fissile material. This feature can analyze the content of isotopic fissile. From 1keV to 0.1eV energy range, the energy resolution is enough to get the individual fissile fission signatures. The dominant fission signature is shown below 1eV for each fissile isotope. The neutron generation system with target was designed to get fission signals by fissile materials. The system was decided to overcome neutron backgrounds and to get good counting statistics. Finally, an accurate fissile material content will contribute to safety of spent fuel reuse in future nuclear energy system and optimum design of spent fuel storage site. Additionally, an accurate fissile material content will increase international transparence and credibility for the reuse of PWR spent fuel.

  16. LSDS Development for Isotopic Fissile Assay in Spent Fuel

    International Nuclear Information System (INIS)

    Lee, Yong Deok; Park, Chang Je; Park, Geun Il; Lee, Jung Won; Song, Kee Chan

    2011-01-01

    As an option to reduce a spent fuel and reuse an existing fissile material in spent fuel, sodium fast reactor SFR program linked with pyro-processing is under development in KAERI. A uranium-TRU mixture through a pyro-process is used to fabricate SFR fuel. An assay of isotopic fissile content plays an important role in an optimum design of storage site and reuse of fissile materials of spent fuel. Lead slowing down spectrometer LSDS is being developed in KAERI to analyze isotopic fissile material content. LSDS has several features: direct fissile assay, near real time fissile assay, no influence from radiation background, fissile isotopic assay and applicable to spent fuel and recycled fuel. Based on the designed geometry, neutron energy resolution was investigated. The neutron energy spectrum was analyzed as well. Spent fuel emits large number of neutrons by spontaneous fission. Neutron generator must overcome the neutron background to get the pure fission signals from fissile materials. Neutron generator is planned to have compact system with one section electron linac which is easy maintenance, less cost and high neutron yield. The LSD has the power to resolve the fission characteristics from each fissile material. This feature can analyze the content of isotopic fissile. From 1keV to 0.1eV energy range, the energy resolution is enough to get the individual fissile fission signatures. The dominant fission signature is shown below 1eV for each fissile isotope. The neutron generation system with target was designed to get fission signals by fissile materials. The system was decided to overcome neutron backgrounds and to get good counting statistics. Finally, an accurate fissile material content will contribute to safety of spent fuel reuse in future nuclear energy system and optimum design of spent fuel storage site. Additionally, an accurate fissile material content will increase international transparence and credibility for the reuse of PWR spent fuel

  17. Scientific reference on the long time evolution of spent fuels; Referentiel scientifique sur l'evolution a long terme des combustibles uses

    Energy Technology Data Exchange (ETDEWEB)

    Ferry, C.; Poinssot, Ch.; Broudic, V.; Jegou, Ch.; Roudil, D.; Poulesquen, A.; Miserque, F. [CEA Saclay, Dept. de Physico-Chimie, 91 - Gif sur Yvette (France); Cappelaere, Ch. [CEA Saclay, Dept. des Materiaux pour le Nucleaire, 91 - Gif-sur-Yvette (France); Desgranges, L.; Garcia, Ph.; Piron, J.P. [CEA Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. d' Etudes des Combustibles; Lovera, P.; Marimbeau, P. [CEA Cadarache, 13 - Saint Paul lez Durance (France). Dept. d' Etudes des Reacteurs; Corbel, C. [CEA Saclay, Dept. de Recherche sur l' Etat Condense, les Atomes et les Molecules, 91 - Gif sur Yvette (France)

    2005-03-15

    This report is published in the framework of the 1991 French law for the nuclear waste management. The state of the art reported here concerns the long term evolution of spent fuel in the various environmental conditions corresponding to dry storage and geological disposal: closed system, air and water saturated medium. This review is based on the results of the french PRECCI project (Research Program on Long term Evolution of Spent Nuclear Fuel) and on literature data. (authors)

  18. Team Work: Time well Spent

    Science.gov (United States)

    Moore Johnson, Susan; Reinhorn, Stefanie K.; Simon, Nicole S.

    2016-01-01

    Teachers in high-poverty schools often feel stressed and fatigued. We might expect that if we ask these teachers to take on even more work by meeting regularly in collaborative improvement teams, they will respond with skepticism, even resentment. But in a study of 83 teachers in six outstanding high-poverty schools, these researchers found the…

  19. Investigation of metabolites for estimating blood deposition time.

    Science.gov (United States)

    Lech, Karolina; Liu, Fan; Davies, Sarah K; Ackermann, Katrin; Ang, Joo Ern; Middleton, Benita; Revell, Victoria L; Raynaud, Florence J; Hoveijn, Igor; Hut, Roelof A; Skene, Debra J; Kayser, Manfred

    2018-01-01

    Trace deposition timing reflects a novel concept in forensic molecular biology involving the use of rhythmic biomarkers for estimating the time within a 24-h day/night cycle a human biological sample was left at the crime scene, which in principle allows verifying a sample donor's alibi. Previously, we introduced two circadian hormones for trace deposition timing and recently demonstrated that messenger RNA (mRNA) biomarkers significantly improve time prediction accuracy. Here, we investigate the suitability of metabolites measured using a targeted metabolomics approach, for trace deposition timing. Analysis of 171 plasma metabolites collected around the clock at 2-h intervals for 36 h from 12 male participants under controlled laboratory conditions identified 56 metabolites showing statistically significant oscillations, with peak times falling into three day/night time categories: morning/noon, afternoon/evening and night/early morning. Time prediction modelling identified 10 independently contributing metabolite biomarkers, which together achieved prediction accuracies expressed as AUC of 0.81, 0.86 and 0.90 for these three time categories respectively. Combining metabolites with previously established hormone and mRNA biomarkers in time prediction modelling resulted in an improved prediction accuracy reaching AUCs of 0.85, 0.89 and 0.96 respectively. The additional impact of metabolite biomarkers, however, was rather minor as the previously established model with melatonin, cortisol and three mRNA biomarkers achieved AUC values of 0.88, 0.88 and 0.95 for the same three time categories respectively. Nevertheless, the selected metabolites could become practically useful in scenarios where RNA marker information is unavailable such as due to RNA degradation. This is the first metabolomics study investigating circulating metabolites for trace deposition timing, and more work is needed to fully establish their usefulness for this forensic purpose.

  20. Intermodal transfer of spent fuel

    International Nuclear Information System (INIS)

    Neuhauser, K.S.; Weiner, R.F.

    1991-01-01

    As a result of the international standardization of containerized cargo handling in ports around the world, maritime shipment handling is particularly uniform. Thus, handier exposure parameters will be relatively constant for ship-truck and ship-rail transfers at ports throughout the world. Inspectors' doses are expected to vary because of jurisdictional considerations. The results of this study should be applicable to truck-to-rail transfers. A study of the movement of spent fuel casks through ports, including the loading and unloading of containers from cargo vessels, afforded an opportunity to estimate the radiation doses to those individuals handling the spent fuels with doses to the public along subsequent transportation routes of the fuel. A number of states require redundant inspections and for escorts over long distances on highways; thus handlers, inspectors, escort personnel, and others who are not normally classified as radiation workers may sustain doses high enough to warrant concern about occupational safety. This paper addresses the question of radiation safety for these workers. Data were obtained during, observation of the offloading of reactor spent fuel (research reactor spent fuel, in this instance) which included estimates of exposure times and distances for handlers, inspectors and other workers during offloading and overnight storage. Exposure times and distance were also for other workers, including crane operators, scale operators, security personnel and truck drivers. RADTRAN calculational models and parameter values then facilitated estimation of the dose to workers during incident-free ship-to-truck transfer of spent fuel

  1. Lost in hospital: a qualitative interview study that explores the perceptions of NHS inpatients who spent time on clinically inappropriate hospital wards.

    Science.gov (United States)

    Goulding, Lucy; Adamson, Joy; Watt, Ian; Wright, John

    2015-10-01

    Prior research suggests that the placement of patients on clinically inappropriate hospital wards may increase the risk of experiencing patient safety issues. To explore patients' perspectives of the quality and safety of the care received during their inpatient stay on a clinically inappropriate hospital ward. Qualitative study using semi-structured interviews. Nineteen patients who had spent time on at least one clinically inappropriate ward during their hospital stay at a large NHS teaching hospital in England. Patients would prefer to be treated on the correct specialty ward, but it is generally accepted that this may not be possible. When patients are placed on inappropriate wards, they may lack a sense of belonging. Participants commented on potential failings in communication, medical staff availability, nurses' knowledge and the resources available, each of which may contribute to unsafe care. Patients generally acknowledge the need for placement on inappropriate wards due to demand for inpatient beds, but may report dissatisfaction in terms of preference and belonging. Importantly, patients recount issues resulting from this placement that may compromise their safety. Hospital managers should be encouraged to appreciate this insight and potential threat to safe practice and where possible avoid inappropriate ward transfers and admissions. Where such admissions are unavoidable, staff should take action to address the gaps in safety of care that have been identified. © 2013 John Wiley & Sons Ltd.

  2. Randomized Video-Feedback Intervention in Home-Based Childcare: Improvement of Children's Wellbeing Dependent on Time Spent with Trusted Caregiver.

    Science.gov (United States)

    Groeneveld, Marleen G; Vermeer, Harriet J; van IJzendoorn, Marinus H; Linting, Mariëlle

    The childcare environment offers a wide array of developmental opportunities for children. Providing children with a feeling of security to explore this environment is one of the most fundamental goals of childcare. In the current study the effectiveness of Video-feedback Intervention to promote Positive Parenting-Child Care (VIPP-CC) was tested on children's wellbeing in home-based childcare in a randomized controlled trial. Forty-seven children and their caregivers were randomly assigned to the intervention group or control group. Children's wellbeing, caregiver sensitivity, and global childcare quality were observed during a pretest and a posttest. We did not find an overall intervention effect on child wellbeing, but a significant interaction effect with months spent with a trusted caregiver was present. Children who were less familiar with the caregiver showed an increase in wellbeing scores in both the intervention and control group, but for the group of children who were more familiar with the caregiver, wellbeing increased only in the intervention group. Although there was no overall effect of the VIPP-CC on children's wellbeing, the VIPP-CC seems effective in children who have been cared for by the same trusted caregiver for a longer period of time.

  3. Quality of time spent without symptoms of disease or toxicity of treatment for transmetatarsal amputation versus digital amputation in diabetic patients with digital gangrene.

    Science.gov (United States)

    Elsherif, Mohamed; Tawfick, Wael; Canning, Patrick; Hynes, Niamh; Sultan, Sherif

    2018-04-01

    Aim We aim to compare the outcome of diabetic patients with gangrenous toes who were managed initially either by digital amputation or by transmetatarsal amputation. The null hypothesis is that transmetatarsal amputation had less theatre trips and better healing. Materials and Methods A parallel observational comparative study of all diabetic patients who underwent either digital or transmetatarsal amputation in a tertiary referral center from 2002 through 2015. Comorbid conditions, subsequent amputations, hospital stay, and readmission were noted. Results A total of 223 patients underwent minor amputation during the study period, of which 147 patients were diabetic and 76 patients were non-diabetic. Seventy-seven patients had digital amputation and 70 transmetatarsal amputation in diabetic patients. Demographics were similar in both groups. The median time to major amputation was (400 ± IQR 1205 days) in the digital amputation group, compared to 690 ± IQR 891 days in the transmetatarsal amputation group ( P = 0.974). 29.9% of digital amputations and 15.7% of transmetatarsal amputations in diabetic patients, required minor amputations or revision procedures ( P = 0.04). Median length of hospital stay was (20 days, IQR 27) in the digital group and (17 days, IQR17) in the transmetatarsal amputation group ( P = 0.17). Need for re-admission was 48.1% in digital patients compared to 50% in transmetatarsal amputation patients ( P = 0.81). Quality of time spent without symptoms of disease or toxicity of treatment (Q-TWiST) was (315 days, IQR 45) in digital group and (346 days, IQR 48) in the transmetatarsal amputation patients ( P = 0.099). Conclusion Despite the lack of statistical significance, transmetatarsal amputation offered better outcome in the diabetic patients, with less re-intervention rate, shorter hospital stays, less theatre trips, and longer time without toxicity (TWiST).

  4. Investigations on response time of magnetorheological elastomer under compression mode

    Science.gov (United States)

    Zhu, Mi; Yu, Miao; Qi, Song; Fu, Jie

    2018-05-01

    For efficient fast control of vibration system with magnetorheological elastomer (MRE)-based smart device, the response time of MRE material is the key parameter which directly affects the control performance of the vibration system. For a step coil current excitation, this paper proposed a Maxwell behavior model with time constant λ to describe the normal force response of MRE, and the response time of MRE was extracted through the separation of coil response time. Besides, the transient responses of MRE under compression mode were experimentally investigated, and the effects of (i) applied current, (ii) particle distribution and (iii) compressive strain on the response time of MRE were addressed. The results revealed that the three factors can affect the response characteristic of MRE quite significantly. Besides the intrinsic importance for contributing to the response evaluation and effective design of MRE device, this study may conduce to the optimal design of controller for MRE control system.

  5. Thermal model of spent fuel transport cask

    International Nuclear Information System (INIS)

    Ahmed, E.E.M.; Rahman, F.A.; Sultan, G.F.; Khalil, E.E.

    1996-01-01

    The investigation provides a theoretical model to represent the thermal behaviour of the spent fuel elements when transported in a dry shipping cask under normal transport conditions. The heat transfer process in the spent fuel elements and within the cask are modeled which include the radiant heat transfer within the cask and the heat transfer by thermal conduction within the spent fuel element. The model considers the net radiant method for radiant heat transfer process from the inner most heated element to the surrounding spent elements. The heat conduction through fuel interior, fuel-clad interface and on clad surface are also presented. (author) 6 figs., 9 refs

  6. The Effect of High Versus Low Teacher Affect and Passive Versus Active Student Activity During Music Listening on Preschool Children's Attention, Piece Preference, Time Spent Listening, and Piece Recognition.

    Science.gov (United States)

    Sims, Wendy L.

    1986-01-01

    Small-group listening lessons and subsequent individual posttests were used to judge 94 three- through five-year-old subjects' attention, paired-comparison piece preference, time spent listening, and piece recognition. Research procedures included a modified multiple baseline design and split-screen video taping of instructional sessions.…

  7. Investigations of possibilities to dispose of spent nuclear fuel in Lithuania: a model case. Volume 3, Generic Safety Assessment of Repository in Crystalline Rocks

    International Nuclear Information System (INIS)

    Motiejunas, S.; Poskas, P.

    2005-01-01

    In this Volume a generic safety assessment of the repository for spent nuclear fuel in crystalline rock in Lithuania is presented. Modeling of safety relevant radionuclide release from the defected canister and their transport through the near field and far field was performed. Doses to humans due to released radionuclides in the well water were calculated and compared with the dose restrictions existing in Lithuania. For this stage of generic safety assessment only two scenarios were chosen: base scenario and canister defect scenario. KBS-3 concept developed by SKB for disposal of spent nuclear fuel in Sweden was chosen as prototype for repository in crystalline basement in Lithuania. The KBS-3H design with horizontal canister emplacement is proposed as a reference design for Lithuania

  8. Determining initial enrichment, burnup, and cooling time of pressurized-water-reactor spent fuel assemblies by analyzing passive gamma spectra measured at the Clab interim-fuel storage facility in Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Favalli, A., E-mail: afavalli@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM (United States); Vo, D. [Los Alamos National Laboratory, Los Alamos, NM (United States); Grogan, B. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Jansson, P. [Uppsala University, Uppsala (Sweden); Liljenfeldt, H. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Mozin, V. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Schwalbach, P. [European Commission, DG Energy, Euratom Safeguards Luxemburg, Luxemburg (Luxembourg); Sjöland, A. [Swedish Nuclear Fuel and Waste Management Company, Stockholm (Sweden); Tobin, S.J.; Trellue, H. [Los Alamos National Laboratory, Los Alamos, NM (United States); Vaccaro, S. [European Commission, DG Energy, Euratom Safeguards Luxemburg, Luxemburg (Luxembourg)

    2016-06-01

    The purpose of the Next Generation Safeguards Initiative (NGSI)–Spent Fuel (SF) project is to strengthen the technical toolkit of safeguards inspectors and/or other interested parties. The NGSI–SF team is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay measurements of spent fuel assemblies: (1) verify the initial enrichment, burnup, and cooling time of facility declaration; (2) detect the diversion or replacement of pins; (3) estimate the plutonium mass [which is also a function of the variables in (1)]; (4) estimate the decay heat; and (5) determine the reactivity of spent fuel assemblies. Since August 2013, a set of measurement campaigns has been conducted at the Central Interim Storage Facility for Spent Nuclear Fuel (Clab), in collaboration with Swedish Nuclear Fuel and Waste Management Company (SKB). One purpose of the measurement campaigns was to acquire passive gamma spectra with high-purity germanium and lanthanum bromide scintillation detectors from Pressurized Water Reactor and Boiling Water Reactor spent fuel assemblies. The absolute {sup 137}Cs count rate and the {sup 154}Eu/{sup 137}Cs, {sup 134}Cs/{sup 137}Cs, {sup 106}Ru/{sup 137}Cs, and {sup 144}Ce/{sup 137}Cs isotopic ratios were extracted; these values were used to construct corresponding model functions (which describe each measured quantity’s behavior over various combinations of burnup, cooling time, and initial enrichment) and then were used to determine those same quantities in each measured spent fuel assembly. The results obtained in comparison with the operator declared values, as well as the methodology developed, are discussed in detail in the paper.

  9. Determining initial enrichment, burnup, and cooling time of pressurized-water-reactor spent fuel assemblies by analyzing passive gamma spectra measured at the Clab interim-fuel storage facility in Sweden

    Science.gov (United States)

    Favalli, A.; Vo, D.; Grogan, B.; Jansson, P.; Liljenfeldt, H.; Mozin, V.; Schwalbach, P.; Sjöland, A.; Tobin, S. J.; Trellue, H.; Vaccaro, S.

    2016-06-01

    The purpose of the Next Generation Safeguards Initiative (NGSI)-Spent Fuel (SF) project is to strengthen the technical toolkit of safeguards inspectors and/or other interested parties. The NGSI-SF team is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay measurements of spent fuel assemblies: (1) verify the initial enrichment, burnup, and cooling time of facility declaration; (2) detect the diversion or replacement of pins; (3) estimate the plutonium mass [which is also a function of the variables in (1)]; (4) estimate the decay heat; and (5) determine the reactivity of spent fuel assemblies. Since August 2013, a set of measurement campaigns has been conducted at the Central Interim Storage Facility for Spent Nuclear Fuel (Clab), in collaboration with Swedish Nuclear Fuel and Waste Management Company (SKB). One purpose of the measurement campaigns was to acquire passive gamma spectra with high-purity germanium and lanthanum bromide scintillation detectors from Pressurized Water Reactor and Boiling Water Reactor spent fuel assemblies. The absolute 137Cs count rate and the 154Eu/137Cs, 134Cs/137Cs, 106Ru/137Cs, and 144Ce/137Cs isotopic ratios were extracted; these values were used to construct corresponding model functions (which describe each measured quantity's behavior over various combinations of burnup, cooling time, and initial enrichment) and then were used to determine those same quantities in each measured spent fuel assembly. The results obtained in comparison with the operator declared values, as well as the methodology developed, are discussed in detail in the paper.

  10. Spent fuel management in Japan

    International Nuclear Information System (INIS)

    Shirahashi, K.; Maeda, M.; Nakai, T.

    1996-01-01

    Japan has scarce energy resources and depends on foreign resources for 84% of its energy needs. Therefore, Japan has made efforts to utilize nuclear power as a key energy source since mid-1950's. Today, the nuclear energy produced from 49 nuclear power plants is responsible for about 31% of Japan's total electricity supply. The cumulative amount of spent fuel generated as of March 1995 was about 11,600 Mg U. Japan's policy of spent fuel management is to reprocess spent nuclear fuel and recycle recovered plutonium and uranium as nuclear fuel. The Tokai reprocessing plant continues stable operation keeping the annual treatment capacity or around 90 Mg U. A commercial reprocessing plant is under construction at Rokkasho, northern part of Japan. Although FBR is the principal reactor to use plutonium, LWR will be a major power source for some time and recycling of the fuel in LWRs will be prompted. (author). 3 figs

  11. Detailed investigation of a time-of-flight neutron spectrometer

    International Nuclear Information System (INIS)

    Elevant, T.; Trostell, B.

    1981-02-01

    Properties of a neutron spectrometer and telescope, based on double neutron interaction in hydrogen based scintillators and neutron time-of-flight technique, have been investigated in detail. Theoretical scaling of the resolutions with the flight path length and scattering angle have been confirmed by experimental results. Important parameters in connection with calibration of the spectrometer are discussed and calculated relative resolutions of the ion temperature are shown when applied to a fusion deuterium plasma. (Auth.)

  12. Spent nuclear fuel transport problems

    International Nuclear Information System (INIS)

    Kondrat'ev, A.N.; Kosarev, Yu.A.; Yulikov, E.I.

    1977-01-01

    The paper considers the problems of shipping spent fuel from nuclear power stations to reprocessing plants and also the principal ways of solving these problems with a view to achieving maximum economy and safety in transport. The increase in the number of nuclear power plants in the USSR will entail an intensification of spent-fuel shipments. Higher burnup and the need to reduce cooling time call for heavier and more complex shipping containers. The problem of shipping spent fuel should be tackled comprehensively, bearing in mind the requirements of safety and economy. One solution to these problems is to develop rational and cheap designs of such containers. In addition, the world-wide trend towards more thorough protection of the environment against pollution and of the health of the population requires the devotion of constant attention to improving the reliability and safety of shipments. The paper considers the prospects for nuclear power development in the USSR and in other member countries of the CMEA (1976-1980), the composition and design of some Soviet packaging assemblies, the appropriate cooling time for spent fuel from thermal reactor power stations, procedures for reducing fuel-shipping costs, some methodological problems of container calculation and design, and finally problems of testing and checking containers on test rigs. (author)

  13. Covariant Density Functionals: time-odd channel investigated

    International Nuclear Information System (INIS)

    Afanasjev, A. V.; Abusara, H.

    2009-01-01

    The description of exotic nuclear systems and phenomena requires a detailed understanding of all channels of density functional theories. The role of time-odd mean fields, their evidence in experiment, and an accurate description of these fields are subject of current interest. Recent studies advanced the understanding of these fields in energy density functional theories based on the Skyrme force [1,2]. Time-odd mean fields are related to nuclear magnetism in covariant density functional (CDF) theories [3]. They arise from space-like components of vector mesons and Lorentz invariance requires that their coupling strengths are identical to that of time-like components. There were only few limited efforts to understand the role of time-odd mean fields in covariant density functional theory [4,5]. For example, the microscopic role of nuclear magnetism and its impact on rotational properties of nuclei has been studied in Ref. [5]. It is known that time-odd mean fields modify the angular momentum content of the single-particle orbitals and thus the moments of inertia, effective alignments, alignment gains at the band crossings and other physical observables. We aim on more detailed and systematic understanding of the role of time-odd mean fields in covariant density functional theory. This investigation covers both rotating and non-rotating systems. It is shown that contrary to the Skyrme energy density functionals time-odd mean fields of CDF theory always provide additional binding in the systems with broken time-reversal symmetry (rotating nuclei, odd mass nuclei). This additional binding increases with spin and has its maximum exactly at the terminating state [6], where it can reach several MeV. The impact of time-odd mean fields on the properties of rotating systems has been studied in a systematic way (as a function of particle number and deformation) across the nuclear chart [7]. In addition, this contribution extends these studies to non-rotating systems such as

  14. Experimental Investigation of Heat Transfer during Night-Time Ventilation

    DEFF Research Database (Denmark)

    Artmann, Nikolai; Jensen, Rasmus Lund; Manz, H.

    2010-01-01

    is the heat transfer at the internal room surfaces. Increased convection is expected due to high air flow rates and the possibility of a cold air jet flowing along the ceiling, but the magnitude of these effects is hard to predict. In order to improve the predictability, heat transfer during night......-time ventilation in case of mixing and displacement ventilation has been investigated in a full scale test room. The results show that for low air flow rates displacement ventilation is more efficient than mixing ventilation. For higher air flow rates the air jet flowing along the ceiling has a significant effect...

  15. Numerical investigation of the late-time Kerr tails

    Energy Technology Data Exchange (ETDEWEB)

    Racz, Istvan; Toth, Gabor Zs, E-mail: iracz@rmki.kfki.hu, E-mail: tgzs@rmki.kfki.hu [RMKI, H-1121 Budapest, Konkoly Thege Miklos ut 29-33 (Hungary)

    2011-10-07

    The late-time behavior of a scalar field on fixed Kerr background is examined in a numerical framework incorporating the techniques of conformal compactification and hyperbolic initial value formulation. The applied code is 1+(1+2) as it is based on the use of the spectral method in the angular directions while in the time-radial section fourth order finite differencing, along with the method of lines, is applied. The evolution of various types of stationary and non-stationary pure multipole initial states are investigated. The asymptotic decay rates are determined not only in the domain of outer communication but along the event horizon and at future null infinity as well. The decay rates are found to be different for stationary and non-stationary initial data, and they also depend on the fall off properties of the initial data toward future null infinity. The energy and angular momentum transfers are found to show significantly different behavior in the initial phase of the time evolution. The quasinormal ringing phase and the tail phase are also investigated. In the tail phase, the decay exponents for the energy and angular momentum losses at I{sup +} are found to be smaller than at the horizon which is in accordance with the behavior of the field itself and it means that at late times the energy and angular momentum falling into the black hole become negligible in comparison with the energy and angular momentum radiated toward I{sup +}. The energy and angular momentum balances are used as additional verifications of the reliability of our numerical method.

  16. Numerical investigation of the late-time Kerr tails

    International Nuclear Information System (INIS)

    Racz, Istvan; Toth, Gabor Zs

    2011-01-01

    The late-time behavior of a scalar field on fixed Kerr background is examined in a numerical framework incorporating the techniques of conformal compactification and hyperbolic initial value formulation. The applied code is 1+(1+2) as it is based on the use of the spectral method in the angular directions while in the time-radial section fourth order finite differencing, along with the method of lines, is applied. The evolution of various types of stationary and non-stationary pure multipole initial states are investigated. The asymptotic decay rates are determined not only in the domain of outer communication but along the event horizon and at future null infinity as well. The decay rates are found to be different for stationary and non-stationary initial data, and they also depend on the fall off properties of the initial data toward future null infinity. The energy and angular momentum transfers are found to show significantly different behavior in the initial phase of the time evolution. The quasinormal ringing phase and the tail phase are also investigated. In the tail phase, the decay exponents for the energy and angular momentum losses at I + are found to be smaller than at the horizon which is in accordance with the behavior of the field itself and it means that at late times the energy and angular momentum falling into the black hole become negligible in comparison with the energy and angular momentum radiated toward I + . The energy and angular momentum balances are used as additional verifications of the reliability of our numerical method.

  17. Considerations Regarding ROK Spent Nuclear Fuel Management Options

    International Nuclear Information System (INIS)

    Braun, Chaim; Forrest, Robert

    2013-01-01

    In this paper we discuss spent fuel management options in the Republic of Korea (ROK) from two interrelated perspectives: Centralized dry cask storage and spent fuel pyroprocessing and burning in sodium fast reactors (SFRs). We argue that the ROK will run out of space for at-reactors spent fuel storage by about the year 2030 and will thus need to transition centralized dry cask storage. Pyroprocessing plant capacity, even if approved and successfully licensed and constructed by that time, will not suffice to handle all the spent fuel discharged annually. Hence centralized dry cask storage will be required even if the pyroprocessing option is successfully developed by 2030. Pyroprocessing is but an enabling technology on the path leading to fissile material recycling and burning in future SFRs. In this regard we discuss two SFR options under development in the U. S.: the Super Prism and the Travelling Wave Reactor (TWR). We note that the U. S. is further along in reactor development than the ROK. The ROK though has acquired more experience, recently in investigating fuel recycling options for SFRs. We thus call for two complementary joint R and D project to be conducted by U. S. and ROK scientists. One leading to the development of a demonstration centralized away-from-reactors spent fuel storage facility. The other involve further R and D on a combined SFR-fuel cycle complex based on the reactor and fuel cycle options discussed in the paper

  18. Why are you late? Investigating the role of time management in time-based prospective memory.

    Science.gov (United States)

    Waldum, Emily R; McDaniel, Mark A

    2016-08-01

    Time-based prospective memory tasks (TBPM) are those that are to be performed at a specific future time. Contrary to typical laboratory TBPM tasks (e.g., hit the Z key every 5 min), many real-world TBPM tasks require more complex time-management processes. For instance, to attend an appointment on time, one must estimate the duration of the drive to the appointment and then use this estimate to create and execute a secondary TBPM intention (e.g., "I need to start driving by 1:30 to make my 2:00 appointment on time"). Future under- and overestimates of drive time can lead to inefficient TBPM performance with the former lending to missed appointments and the latter to long stints in the waiting room. Despite the common occurrence of complex TBPM tasks in everyday life, to date, no studies have investigated how components of time management, including time estimation, affect behavior in such complex TBPM tasks. Therefore, the current study aimed to investigate timing biases in both older and younger adults and, further, to determine how such biases along with additional time management components including planning and plan fidelity influence complex TBPM performance. Results suggest for the first time that younger and older adults do not always utilize similar timing strategies, and as a result, can produce differential timing biases under the exact same environmental conditions. These timing biases, in turn, play a vital role in how efficiently both younger and older adults perform a later TBPM task that requires them to utilize their earlier time estimate. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  19. Investigating Unsaturated Zone Travel Times with Tritium and Stable Isotopes

    Science.gov (United States)

    Visser, A.; Thaw, M.; Van der Velde, Y.

    2017-12-01

    Travel times in the unsaturated zone are notoriously difficult to assess. Travel time tracers relying on the conservative transport of dissolved (noble) gases (tritium-helium, CFCs or SF6) are not applicable. Large water volume requirements of other cosmogenic radioactive isotopes (sulfur-35, sodium-22) preclude application in the unsaturated zone. Prior investigations have relied on models, introduced tracers, profiles of stable isotopes or tritium, or a combination of these techniques. Significant unsaturated zone travel times (UZTT) complicate the interpretation of stream water travel time tracers by ranked StorAge Selection (rSAS) functions. Close examination of rSAS functions in a sloping soil lysimeter[1] show the effect of the UZTT on the shape of the rSAS cumulative distribution function. We studied the UZTT at the Southern Sierra Critical Zone Observatory (SS-CZO) using profiles of tritium and stable isotopes (18O and 2H) in the unsaturated zone, supported by soil water content data. Tritium analyses require 100-500 mL of soil water and therefore large soil samples (1-5L), and elaborate laboratory procedures (oven drying, degassing and noble gas mass spectrometry). The high seasonal and interannual variability in precipitation of the Mediterranean climate, variable snow pack and high annual ET/P ratios lead to a dynamic hydrology in the deep unsaturated soils and regolith and highly variable travel time distributions. Variability of the tritium concentration in precipitation further complicates direct age estimates. Observed tritium profiles (>3 m deep) are interpreted in terms of advective and dispersive vertical transport of the input variability and radioactive decay of tritium. Significant unsaturated zone travel times corroborate previously observed low activities of short-lived cosmogenic radioactive nuclides in stream water. Under these conditions, incorporating the UZTT is critical to adequately reconstruct stream water travel time distributions. 1

  20. Why are You Late?: Investigating the Role of Time Management in Time-Based Prospective Memory

    Science.gov (United States)

    Waldum, Emily R; McDaniel, Mark A.

    2016-01-01

    Time-based prospective memory tasks (TBPM) are those that are to be performed at a specific future time. Contrary to typical laboratory TBPM tasks (e.g., “hit the “z” key every 5 minutes”), many real-world TBPM tasks require more complex time-management processes. For instance to attend an appointment on time, one must estimate the duration of the drive to the appointment and then utilize this estimate to create and execute a secondary TBPM intention (e.g., “I need to start driving by 1:30 to make my 2:00 appointment on time”). Future under- and overestimates of drive time can lead to inefficient TBPM performance with the former lending to missed appointments and the latter to long stints in the waiting room. Despite the common occurrence of complex TBPM tasks in everyday life, to date, no studies have investigated how components of time management, including time estimation, affect behavior in such complex TBPM tasks. Therefore, the current study aimed to investigate timing biases in both older and younger adults and further to determine how such biases along with additional time management components including planning and plan fidelity influence complex TBPM performance. Results suggest for the first time that younger and older adults do not always utilize similar timing strategies, and as a result, can produce differential timing biases under the exact same environmental conditions. These timing biases, in turn, play a vital role in how efficiently both younger and older adults perform a later TBPM task that requires them to utilize their earlier time estimate. PMID:27336325

  1. Characteristics of spent nuclear fuel

    International Nuclear Information System (INIS)

    Notz, K.J.

    1988-04-01

    The Office of Civilian Radioactive Waste Management (OCRWM) is responsible for the spent fuels and other wastes that will, or may, eventually be disposed of in a geological repository. The two major sources of these materials are commercial light-water reactor (LWR) spent fuel and immobilized high-level waste (HLW). Other wastes that may require long-term isolation include non-LWR spent fuels and miscellaneous sources such as activated metals. This report deals with spent fuels, but for completeness, the other sources are described briefly. Detailed characterizations are required for all of these potential repository wastes. These characteristics include physical, chemical, and radiological properties. The latter must take into account decay as a function of time. In addition, the present inventories and projected quantities of the various wastes are needed. This information has been assembled in a Characteristics Data Base which provides data in four formats: hard copy standard reports, menu-driven personal computer (PC) data bases, program-level PC data bases, and mainframe computer files. 5 refs., 3 figs., 4 tabs

  2. Spent nuclear fuel storage

    International Nuclear Information System (INIS)

    Romanato, Luiz Sergio

    2005-01-01

    When a country becomes self-sufficient in part of the nuclear cycle, as production of fuel that will be used in nuclear power plants for energy generation, it is necessary to pay attention for the best method of storing the spent fuel. Temporary storage of spent nuclear fuel is a necessary practice and is applied nowadays all over the world, so much in countries that have not been defined their plan for a definitive repository, as well for those that already put in practice such storage form. There are two main aspects that involve the spent fuels: one regarding the spent nuclear fuel storage intended to reprocessing and the other in which the spent fuel will be sent for final deposition when the definitive place is defined, correctly located, appropriately characterized as to several technical aspects, and licentiate. This last aspect can involve decades of studies because of the technical and normative definitions at a given country. In Brazil, the interest is linked with the storage of spent fuels that will not be reprocessed. This work analyses possible types of storage, the international panorama and a proposal for future construction of a spent nuclear fuel temporary storage place in the country. (author)

  3. Alternative Measuring Approaches in Gamma Scanning on Spent Nuclear Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Sihm Kvenangen, Karen

    2007-06-15

    In the future, the demand for energy is predicted to grow and more countries plan to utilize nuclear energy as their source of electric energy. This gives rise to many important issues connected to nuclear energy, such as finding methods that can verify that the spent nuclear fuel has been handled safely and used in ordinary power producing cycles as stated by the operators. Gamma ray spectroscopy is one method used for identification and verification of spent nuclear fuel. In the specific gamma ray spectroscopy method called gamma scanning the gamma radiation from the fission products Cs-137, Cs-134 and Eu-154 are measured in a spent fuel assembly. From the results, conclusions can be drawn about the fuels characteristics. This degree project examines the possibilities of using alternative measuring approaches when using the gamma scanning method. The focus is on examining how to increase the quality of the measured data. How to decrease the measuring time as compared with the present measuring strategy, has also been investigated. The main part of the study comprises computer simulations of gamma scanning measurements. The simulations have been validated with actual measurements on spent nuclear fuel at the central interim storage, Clab. The results show that concerning the quality of the measuring data the conventional strategy is preferable, but with other starting positions and with a more optimized equipment. When focusing on the time aspect, the helical measuring strategy can be an option, but this needs further investigation.

  4. Alternative Measuring Approaches in Gamma Scanning on Spent Nuclear Fuel

    International Nuclear Information System (INIS)

    Sihm Kvenangen, Karen

    2007-06-01

    In the future, the demand for energy is predicted to grow and more countries plan to utilize nuclear energy as their source of electric energy. This gives rise to many important issues connected to nuclear energy, such as finding methods that can verify that the spent nuclear fuel has been handled safely and used in ordinary power producing cycles as stated by the operators. Gamma ray spectroscopy is one method used for identification and verification of spent nuclear fuel. In the specific gamma ray spectroscopy method called gamma scanning the gamma radiation from the fission products Cs-137, Cs-134 and Eu-154 are measured in a spent fuel assembly. From the results, conclusions can be drawn about the fuels characteristics. This degree project examines the possibilities of using alternative measuring approaches when using the gamma scanning method. The focus is on examining how to increase the quality of the measured data. How to decrease the measuring time as compared with the present measuring strategy, has also been investigated. The main part of the study comprises computer simulations of gamma scanning measurements. The simulations have been validated with actual measurements on spent nuclear fuel at the central interim storage, Clab. The results show that concerning the quality of the measuring data the conventional strategy is preferable, but with other starting positions and with a more optimized equipment. When focusing on the time aspect, the helical measuring strategy can be an option, but this needs further investigation

  5. Spent fuel storage for ISER plant

    International Nuclear Information System (INIS)

    Nakajima, Takasuke; Kimura, Yuzi

    1987-01-01

    ISER is an intrinsically safe reactor basing its safety only on physical laws, and uses a steel reactor vessel in order to be economical. For such a new type reactor, it is essentially important to be accepted by the society by showing that the reactor is more profitable than conventional reactors to the public in both technical and economic viewpoint. It is also important that the reactor raises no serious problem in the total fuel cycle. Reprocessing seems one of the major worldwide fuel cycle issues. Spent fuel storage is also one of the key technologies for fuel cycle back end. Various systems for ISER spent fuel storages are examined in the present report. Spent fuel specifications of ISER are similar to those of LWR and therefore, most of LWR spent fuel technologies are basically applicable to ISER spent fuel. Design requirements and examples of storage facilities are also discussed. Dry storage seems to be preferable for the relatively long cooling time spent fuel like ISER's one from economical viewpoint. Vault storage will possibly be the most advantageous for large storage capacity. Another point for discussion is the location and international collaboration for spent fuel storages: ISER expected to be a worldwide energy source and therefore, international spent fuel management seems to be fairly attractive way for an energy recipient country. (Nogami, K.)

  6. Investigating Gender Differences under Time Pressure in Financial Risk Taking.

    Science.gov (United States)

    Xie, Zhixin; Page, Lionel; Hardy, Ben

    2017-01-01

    There is a significant gender imbalance on financial trading floors. This motivated us to investigate gender differences in financial risk taking under pressure. We used a well-established approach from behavior economics to analyze a series of risky monetary choices by male and female participants with and without time pressure. We also used second to fourth digit ratio (2D:4D) and face width-to-height ratio (fWHR) as correlates of pre-natal exposure to testosterone. We constructed a structural model and estimated the participants' risk attitudes and probability perceptions via maximum likelihood estimation under both expected utility (EU) and rank-dependent utility (RDU) models. In line with existing research, we found that male participants are less risk averse and that the gender gap in risk attitudes increases under moderate time pressure. We found that female participants with lower 2D:4D ratios and higher fWHR are less risk averse in RDU estimates. Males with lower 2D:4D ratios were less risk averse in EU estimations, but more risk averse using RDU estimates. We also observe that men whose ratios indicate a greater prenatal exposure to testosterone exhibit a greater optimism and overestimation of small probabilities of success.

  7. Real time application of whole genome sequencing for outbreak investigation - What is an achievable turnaround time?

    Science.gov (United States)

    McGann, Patrick; Bunin, Jessica L; Snesrud, Erik; Singh, Seema; Maybank, Rosslyn; Ong, Ana C; Kwak, Yoon I; Seronello, Scott; Clifford, Robert J; Hinkle, Mary; Yamada, Stephen; Barnhill, Jason; Lesho, Emil

    2016-07-01

    Whole genome sequencing (WGS) is increasingly employed in clinical settings, though few assessments of turnaround times (TAT) have been performed in real-time. In this study, WGS was used to investigate an unfolding outbreak of vancomycin resistant Enterococcus faecium (VRE) among 3 patients in the ICU of a tertiary care hospital. Including overnight culturing, a TAT of just 48.5 h for a comprehensive report was achievable using an Illumina Miseq benchtop sequencer. WGS revealed that isolates from patient 2 and 3 differed from that of patient 1 by a single nucleotide polymorphism (SNP), indicating nosocomial transmission. However, the unparalleled resolution provided by WGS suggested that nosocomial transmission involved two separate events from patient 1 to patient 2 and 3, and not a linear transmission suspected by the time line. Rapid TAT's are achievable using WGS in the clinical setting and can provide an unprecedented level of resolution for outbreak investigations. Published by Elsevier Inc.

  8. Spent sulfite liquor developments

    Energy Technology Data Exchange (ETDEWEB)

    Black, H H

    1958-01-01

    A review of methods of utilizing spent sulfite liquor, including evaporation and burning, fermentation to produce yeast or alcohol, production of vanillin and lignosulfonates, and use as a roadbinder.

  9. Spent fuel management

    International Nuclear Information System (INIS)

    2005-01-01

    The production of nuclear electricity results in the generation of spent fuel that requires safe, secure and efficient management. Appropriate management of the resulting spent fuel is a key issue for the steady and sustainable growth of nuclear energy. Currently about 10,000 tonnes heavy metal (HM) of spent fuel are unloaded every year from nuclear power reactors worldwide, of which 8,500 t HM need to be stored (after accounting for reprocessed fuel). This is the largest continuous source of civil radioactive material generated, and needs to be managed appropriately. Member States have referred to storage periods of 100 years and even beyond, and as storage quantities and durations extend, new challenges arise in the institutional as well as in the technical area. The IAEA gives high priority to safe and effective spent fuel management. As an example of continuing efforts, the 2003 International Conference on Storage of Spent Fuel from Power Reactors gathered 125 participants from 35 member states to exchange information on this important subject. With its large number of Member States, the IAEA is well-positioned to gather and share information useful in addressing Member State priorities. IAEA activities on this topic include plans to produce technical documents as resources for a range of priority topics: spent fuel performance assessment and research, burnup credit applications, cask maintenance, cask loading optimization, long term storage requirements including records maintenance, economics, spent fuel treatment, remote technology, and influence of fuel design on spent fuel storage. In addition to broader topics, the IAEA supports coordinated research projects and technical cooperation projects focused on specific needs

  10. Dead time and recovery time investigations on grinding plants with the aid of radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Roetzer, H; Hagspiel, W

    1977-02-01

    With the aid of the radionuclides Mn 56 and Na 24 as tracers, respectively, the following characteristics were investigated for a roller mill and for a tandem air-swept grinding plant: the time of passage of the mill feed material, the retention time distribution in the grinding system (most frequent and mean retention time), and the time required for, respectively, 50%, 90% and 95% of the material to pass, in some instances separately for the three raw material components limestone, clay and sand. In addition, in the case of the air-swept grinding plant the time required for conveying the raw meal sample from the sampling point to the X-ray fluorescence analysis apparatus was determined. The mean retention time of the material in the two roller mills IV and V was 2.93 and 2.55 minutes respectively; for the tandem air-swept grinding plant it was 8 minutes. The time taken for 90% of the mill feed to pass through the mill was 5.5 and 5 minutes for the roller mills respectively and was about 18.3 minutes for the air-swept plant. The dead time vor conveying the raw meal sample to the X-ray fluorescence apparatus, including further grinding of the sample in a vibratory mill, was 12 minutes.

  11. Investigating how high school deaf students spend their leisure time

    Directory of Open Access Journals (Sweden)

    Allahyar Arabmomeni

    2012-09-01

    Full Text Available This paper presents an investigation on deaf students' interests in spending their leisure times. We design a questionnaire and distribute among all deaf students who are enrolled in high schools in two provinces of Iran. The questionnaire consists of three parts, in the first part, we ask female and male deaf students about their interests in various entertainment activities in Likert scale. In terms of gender, we find out that walking inside or outside house is number one favorite exercise for female students while male students mostly prefer to walk on the streets. Although male students prefer to go biking or running activities, female students prefer to go for picnic or similar activities. This could be due to limitations on female for running or biking inside cities. While going to picnic with members of family or friends is the third popular activity for male students, stretching exercises is third most popular activity among female students. Breathing exercise is the fourth most popular activity among both male and female students. The second part of the survey is associated with the barriers for having no exercise among deaf students. According to our survey, while lack of good attention from public and ordinary people on exercising deaf students is believed to be number one barrier among male students, female students blame lack of transportation facilities as the most important barrier. However, both female and male students believe these two items are the most important factors preventing them to exercise. Lack of awareness for exercising deaf students and lack of good recreational facilities are the third most important barriers among male and female students. The last part of the survey attempted to detect important entertainment activities. Watching TV, entertaining with mobile devices, chatting with friends and watching DVD or movies were the most important items influencing deaf students' free times.DOI: 10.5267/j.msl.2012

  12. Future Time Orientation and Student Expectations: An Empirical Investigation

    Science.gov (United States)

    Amyx, Douglas; Bristow, Dennis

    2004-01-01

    Navajo and Anglo college students' time orientation scores from the Future Time Orientation (FTO) Scale (Bristol & Amyx, 1996) were analyzed and compared. Anglo students were found to be significantly more future time oriented in two of the three dimensions: temporal distance and involvement with time. Future time orientation was used to explain…

  13. Advances in HTGR spent fuel treatment technology

    International Nuclear Information System (INIS)

    Holder, N.D.; Lessig, W.S.

    1984-08-01

    GA Technologies, Inc. has been investigating the burning of spent reactor graphite under Department of Energy sponsorship since 1969. Several deep fluidized bed burners have been used at the GA pilot plant to develop graphite burning techniques for both spent fuel recovery and volume reduction for waste disposal. Since 1982 this technology has been extended to include more efficient circulating bed burners. This paper includes updates on high-temperature gas-cooled reactor fuel cycle options and current results of spent fuel treatment testing for fluidized and advanced circulating bed burners

  14. Extended storage of spent fuel

    International Nuclear Information System (INIS)

    1992-10-01

    This document is the final report on the IAEA Co-ordinated Research Programme on the Behaviour of Spent Fuel and Storage Facility Components during Long Term Storage (BEFAST-II, 1986-1991). It contains the results on wet and dry spent fuel storage technologies obtained from 16 organizations representing 13 countries who participated in the co-ordinated research programme. Considerable quantities of spent fuel continue to arise and accumulate. Many countries are investigating the option of extended spent fuel storage prior to reprocessing or fuel disposal. Wet storage continues to predominate as an established technology with the construction of additional away-from-reactor storage pools. However, dry storage is increasingly used with most participants considering dry storage concepts for the longer term. Depending on the cladding type options of dry storage in air or inert gas are proposed. Dry storage is becoming widely used as a supplement to wet storage for zirconium alloy clad oxide fuels. Storage periods as long as under wet conditions appear to be feasible. Dry storage will also continue to be used for Al clad and Magnox type fuel. Enhancement of wet storage capacity will remain an important activity. Rod consolidation to increase wet storage capacity will continue in the UK and is being evaluated for LWR fuel in the USA, and may start in some other countries. High density storage racks have been successfully introduced in many existing pools and are planned for future facilities. For extremely long wet storage (≥50 years), there is a need to continue work on fuel integrity investigations and LWR fuel performance modelling. it might be that pool component performance in some cases could be more limiting than the FA storage performance. It is desirable to make concerted efforts in the field of corrosion monitoring and prediction of fuel cladding and poll component behaviour in order to maintain good experience of wet storage. Refs, figs and tabs

  15. Spent fuel storage facility, Kalpakkam

    International Nuclear Information System (INIS)

    Shreekumar, B.; Anthony, S.

    2017-01-01

    Spent Fuel Storage Facility (SFSF), Kalpakkam is designed to store spent fuel arising from PHWRs. Spent fuel is transported in AERB qualified/authorized shipping cask by NPCIL to SFSF by road or rail route. The spent fuel storage facility at Kalpakkam was hot commissioned in December 2006. All systems, structures and components (SSCs) related to safety are designed to meet the operational requirements

  16. Disposal of spent fuel

    International Nuclear Information System (INIS)

    Blomeke, J.O.; Ferguson, D.E.; Croff, A.G.

    1978-01-01

    Based on preliminary analyses, spent fuel assemblies are an acceptable form for waste disposal. The following studies appear necessary to bring our knowledge of spent fuel as a final disposal form to a level comparable with that of the solidified wastes from reprocessing: 1. A complete systems analysis is needed of spent fuel disposition from reactor discharge to final isolation in a repository. 2. Since it appears desirable to encase the spent fuel assembly in a metal canister, candidate materials for this container need to be studied. 3. It is highly likely that some ''filler'' material will be needed between the fuel elements and the can. 4. Leachability, stability, and waste-rock interaction studies should be carried out on the fuels. The major disadvantages of spent fuel as a disposal form are the lower maximum heat loading, 60 kW/acre versus 150 kW/acre for high-level waste from a reprocessing plant; the greater long-term potential hazard due to the larger quantities of plutonium and uranium introduced into a repository; and the possibility of criticality in case the repository is breached. The major advantages are the lower cost and increased near-term safety resulting from eliminating reprocessing and the treatment and handling of the wastes therefrom

  17. TRIGA Mark II Ljubljana - spent fuel transportation

    International Nuclear Information System (INIS)

    Ravnik, M.; Dimic, V.

    2008-01-01

    The most important activity in 1999 was shipment of the spent fuel elements back to the United States for final disposal. This activity started already in 1998 with some governmental support. In July 1999 all spent fuel elements (219 pieces) from the TRIGA research reactor in Ljubljana were shipped back to the United Stated by the ship from the port Koper in Slovenia. At the same time shipment of the spent fuel from the research reactor in Pitesti, Romania, and the research reactor in Rome, Italy, was conducted. During the loading the radiation exposure to the workers was rather low. The loading and shipment of the spent nuclear fuel went very smoothly and according the accepted time table. During the last two years the TRIGA research reactor in Ljubljana has been in operation about 1100 hours per year and without any undesired shut-down. (authors)

  18. Guidebook on spent fuel storage

    International Nuclear Information System (INIS)

    1984-01-01

    The Guidebook summarizes the experience and information in various areas related to spent fuel storage: technological aspects, the transport of spent fuel, economical, regulatory and institutional aspects, international safeguards, evaluation criteria for the selection of a specific spent fuel storage concept, international cooperation on spent fuel storage. The last part of the Guidebook presents specific problems on the spent fuel storage in the United Kingdom, Sweden, USSR, USA, Federal Republic of Germany and Switzerland

  19. Spent fuel receipt scenarios study

    International Nuclear Information System (INIS)

    Ballou, L.B.; Montan, D.N.; Revelli, M.A.

    1990-09-01

    This study reports on the results of an assignment from the DOE Office of Civilian Radioactive Waste Management to evaluate of the effects of different scenarios for receipt of spent fuel on the potential performance of the waste packages in the proposed Yucca Mountain high-level waste repository. The initial evaluations were performed and an interim letter report was prepared during the fall of 1988. Subsequently, the scope of work was expanded and additional analyses were conducted in 1989. This report combines the results of the two phases of the activity. This study is a part of a broader effort to investigate the options available to the DOE and the nuclear utilities for selection of spent fuel for acceptance into the Federal Waste Management System for disposal. Each major element of the system has evaluated the effects of various options on its own operations, with the objective of providing the basis for performing system-wide trade-offs and determining an optimum acceptance scenario. Therefore, this study considers different scenarios for receipt of spent fuel by the repository only from the narrow perspective of their effect on the very-near-field temperatures in the repository following permanent closure. This report is organized into three main sections. The balance of this section is devoted to a statement of the study objective, a summary of the assumptions. The second section of the report contains a discussion of the major elements of the study. The third section summarizes the results of the study and draws some conclusions from them. The appendices include copies of the waste acceptance schedule and the existing and projected spent fuel inventory that were used in the study. 10 refs., 27 figs

  20. Spent fuel pyroprocessing demonstration

    International Nuclear Information System (INIS)

    McFarlane, L.F.; Lineberry, M.J.

    1995-01-01

    A major element of the shutdown of the US liquid metal reactor development program is managing the sodium-bonded spent metallic fuel from the Experimental Breeder Reactor-II to meet US environmental laws. Argonne National Laboratory has refurbished and equipped an existing hot cell facility for treating the spent fuel by a high-temperature electrochemical process commonly called pyroprocessing. Four products will be produced for storage and disposal. Two high-level waste forms will be produced and qualified for disposal of the fission and activation products. Uranium and transuranium alloys will be produced for storage pending a decision by the US Department of Energy on the fate of its plutonium and enriched uranium. Together these activities will demonstrate a unique electrochemical treatment technology for spent nuclear fuel. This technology potentially has significant economic and technical advantages over either conventional reprocessing or direct disposal as a high-level waste option

  1. Spent Fuel in Chile

    International Nuclear Information System (INIS)

    López Lizana, F.

    2015-01-01

    The government has made a complete and serious study of many different aspects and possible road maps for nuclear electric power with strong emphasis on safety and energy independence. In the study, the chapter of SFM has not been a relevant issue at this early stage due to the fact that it has been left for later implementation stage. This paper deals with the options Chile might consider in managing its Spent Fuel taking into account foreign experience and factors related to safety, economics, public acceptance and possible novel approaches in spent fuel treatment. The country’s distinctiveness and past experience in this area taking into account that Chile has two research reactors which will have an influence in the design of the Spent Fuel option. (author)

  2. Determinants of Sedentary Behavior, Motivation, Barriers and Strategies to Reduce Sitting Time in Older Women: A Qualitative Investigation

    Directory of Open Access Journals (Sweden)

    Sebastien F. M. Chastin

    2014-01-01

    Full Text Available Sedentary behavior defined as time spent non-exercising seated or reclining posture has been identified has a health risk and associated with frailty and disablement for older adults. Older adults are the most sedentary segment of society. To date no study has investigated the determinants of sedentary behavior in older adults. This study reports a qualitative investigation of the determinants of sedentary behavior, strategies and motivator to reduce sitting time by structured interviews in a group of community dwelling older women (N = 11, age 65 and over. Older women expressed the view that their sedentary behavior is mostly determined by pain which acts both as an incentive to sit and a motivator to stand up, lack of energy in the afternoon, pressure from direct social circle to sit and rest, societal and environmental typecasting that older adult are meant to sit, lack of environmental facilities to allow activity pacing. This qualitative investigation highlighted some factors that older adults consider determinants of their sedentary behavior. Some are identical to those affecting physical activity (self-efficacy, functional limitations, ageist stereotyping but some appear specific to sedentary behavior (locus of control, pain and should be further investigated and considered during intervention design. Tailored interventions that pay attention to the pattern of sedentary behavior of individuals appear to be supported by the views of older women on their sedentary behavior.

  3. Spent Fuel Working Group Report

    International Nuclear Information System (INIS)

    O'Toole, T.

    1993-11-01

    The Department of Energy is storing large amounts of spent nuclear fuel and other reactor irradiated nuclear materials (herein referred to as RINM). In the past, the Department reprocessed RINM to recover plutonium, tritium, and other isotopes. However, the Department has ceased or is phasing out reprocessing operations. As a consequence, Department facilities designed, constructed, and operated to store RINM for relatively short periods of time now store RINM, pending decisions on the disposition of these materials. The extended use of the facilities, combined with their known degradation and that of their stored materials, has led to uncertainties about safety. To ensure that extended storage is safe (i.e., that protection exists for workers, the public, and the environment), the conditions of these storage facilities had to be assessed. The compelling need for such an assessment led to the Secretary's initiative on spent fuel, which is the subject of this report. This report comprises three volumes: Volume I; Summary Results of the Spent Fuel Working Group Evaluation; Volume II, Working Group Assessment Team Reports and Protocol; Volume III; Operating Contractor Site Team Reports. This volume presents the overall results of the Working Group's Evaluation. The group assessed 66 facilities spread across 11 sites. It identified: (1) facilities that should be considered for priority attention. (2) programmatic issues to be considered in decision making about interim storage plans and (3) specific vulnerabilities for some of these facilities

  4. Spent fuel reprocessing options

    International Nuclear Information System (INIS)

    2008-08-01

    The objective of this publication is to provide an update on the latest developments in nuclear reprocessing technologies in the light of new developments on the global nuclear scene. The background information on spent fuel reprocessing is provided in Section One. Substantial global growth of nuclear electricity generation is expected to occur during this century, in response to environmental issues and to assure the sustainability of the electrical energy supply in both industrial and less-developed countries. This growth carries with it an increasing responsibility to ensure that nuclear fuel cycle technologies are used only for peaceful purposes. In Section Two, an overview of the options for spent fuel reprocessing and their level of development are provided. A number of options exist for the treatment of spent fuel. Some, including those that avoid separation of a pure plutonium stream, are at an advanced level of technological maturity. These could be deployed in the next generation of industrial-scale reprocessing plants, while others (such as dry methods) are at a pilot scale, laboratory scale or conceptual stage of development. In Section Three, research and development in support of advanced reprocessing options is described. Next-generation spent fuel reprocessing plants are likely to be based on aqueous extraction processes that can be designed to a country specific set of spent fuel partitioning criteria for recycling of fissile materials to advanced light water reactors or fast spectrum reactors. The physical design of these plants must incorporate effective means for materials accountancy, safeguards and physical protection. Section four deals with issues and challenges related to spent fuel reprocessing. The spent fuel reprocessing options assessment of economics, proliferation resistance, and environmental impact are discussed. The importance of public acceptance for a reprocessing strategy is discussed. A review of modelling tools to support the

  5. Spent-fuel storage: a private sector option

    International Nuclear Information System (INIS)

    Thomas, J.A.; Ross, S.R.

    1983-01-01

    The investigation was performed to delineate the legal and financial considerations for establishing private sector support for the planning and development of an independent spent-fuel storage facility (ISFSF). The preferred institutional structure was found to be one in which a not-for-profit corporation contracts with a limited partnership to handle the spent fuel. The limited partnership acquires the necessary land and constructs the ISFSF facility and then leases the facility to the not-for-profit corporation, which acquires spent-fuel rods from the utilities. The DOE must agree to purchase the spent-fuel rods at the expiration of term and warrant continued operation of the facility if policy changes at the federal level force the removal of the rods prior to completion of the contracted storage cycle. The DOE planning base estimate of spent-fuel storage requirements indicates a market potential adequate to support 10,000 MTU or more of spent-fuel storage prior to the time a government repository is available to accept spent fuel around the turn of the century. The estimated construction cost of a 5000-MTU water basin facility is $552 million. The total capital requirements to finance such a facility are estimated to be $695 million, based on an assumed capital structure of 70 percent debt and 30 percent equity. The estimated total levelized cost of storage, including operating costs, for the assumed 17-year life of the facility is $223 per kilogram of uranium. This is equivalent to a slightly less than one mill per kilowatt-hour increase in nuclear fuel costs at the nuclear power station that was the source of the spent fuel. In conclusion, within the context of the new Nuclear Waste Policy Act of 1982, the study points to both the need for and the advantages of private sector support for one or more ISFSFs and establishes a workable mechanism for the recovery of the costs of owning and operating such facilities. 3 figures, 4 tables

  6. Improved and consistent determination of the nuclear inventory of spent PWR-fuel on the basis of time-dependent cell-calculations with KORIGEN

    International Nuclear Information System (INIS)

    Fischer, U.; Wiese, H.W.

    1983-01-01

    For safe handling, processing and storage of spent nuclear fuel a reliable, experimentally validated method is needed to determine fuel and waste characteristics: composition, radioactivity, heat and radiation. For PWR's, a cell-burnup procedure has been developed which is able to calculate the inventory in consistency with cell geometry, initial enrichment, and reactor control. Routine calculations can be performed with KORIGEN using consistent cross-section sets - burnup-dependent and based on the latest Karlsruhe evaluations for actinides - which were calculated previously with the cell-burnup procedure. Extensive comparisons between calculations and experiments validate the presented procedure. For the use of the KORIGEN code the input description and sample problems are added. Improvements in the calculational method and in data are described, results from KORIGEN, ORIGEN and ORIGEN2 calculations are compared. Fuel and waste inventories are given for BIBLIS-type fuel of different burnup. (orig.) [de

  7. Developing Spent Fuel Assembly for Advanced NDA Instrument Calibration - NGSI Spent Fuel Project

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Jianwei [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gauld, Ian C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Banfield, James [GE Hitachi Nuclear Energy, Wilmington, NC (United States); Skutnik, Steven [Univ. of Tennessee, Knoxville, TN (United States)

    2014-02-01

    This report summarizes the work by Oak Ridge National Laboratory to investigate the application of modeling and simulation to support the performance assessment and calibration of the advanced nondestructive assay (NDA) instruments developed under the Next Generation Safeguards Initiative Spent Fuel (NGSI-SF) Project. Advanced NDA instrument calibration will likely require reference spent fuel assemblies with well-characterized nuclide compositions that can serve as working standards. Because no reference spent fuel standard currently exists, and the practical ability to obtain direct measurement of nuclide compositions using destructive assay (DA) measurements of an entire fuel assembly is prohibitive in the near term due to the complexity and cost of spent fuel experiments, modeling and simulation will be required to construct such reference fuel assemblies. These calculations will be used to support instrument field tests at the Swedish Interim Storage Facility (Clab) for Spent Nuclear Fuel.

  8. Hyperhomocysteinemia, pregnancy complications, and the timing of investigation.

    NARCIS (Netherlands)

    Steegers-Theunissen, R.P.M.; Iersel, C.A. van; Peer, P.G.M.; Nelen, W.L.D.M.; Steegers, E.A.P.

    2004-01-01

    OBJECTIVE: To assess associations between vitamin-dependent homocysteine metabolism and vascular-related pregnancy complications by considering interval between delivery and postpartum investigation and maternal age. METHODS: Case-control study performed at the University Medical Center Nijmegen in

  9. German Approach to Spent Fuel Management

    International Nuclear Information System (INIS)

    Jussofie, A.; Graf, R.; Filbert, W.

    2010-01-01

    in the pilot conditioning facility. The conditioning mode was taken over for the subsequent BSK3 concept which varies in the canister for the fuel rods and the emplacement technology. To prove the principle feasibility of this concept aboveground demonstration tests have been performed by 2009. Investigations on a further concept intended for the direct disposal of spent fuel assemblies without conditioning have just begun. Conceptual differences may have an impact on the safeguards approach. With the end of the moratorium the political situation will change and further steps related to the final disposal of heat-generating waste could be decided. (author)

  10. Probable leaching mechanisms for spent fuel

    International Nuclear Information System (INIS)

    Wang, R.; Katayama, Y.B.

    1981-01-01

    At the Pacific Northwest Laboratory, researchers in the Waste/Rock Interaction Technology Program are studying spent fuel as a possible waste form for the Office of Nuclear Waste Isolation. This paper presents probable leaching mechanisms for spent fuel and discusses current progress in identifying and understanding the leaching process. During the past year, experiments were begun to study the complex leaching mechanism of spent fuel. The initial work in this investigation was done with UO 2 , which provided the most information possible on the behavior of the spent-fuel matrix without encountering the very high radiation levels associated with spent fuel. Both single-crystal and polycrystalline UO 2 samples were used for this study, and techniques applicable to remote experimentation in a hot cell are being developed. The effects of radiation are being studied in terms of radiolysis of water and surface activation of the UO 2 . Dissolution behavior and kinetics of UO 2 were also investigated by electrochemical measurement techniques. These data will be correlated with those acquired when spent fuel is tested in a hot cell. Oxidation effects represent a major area of concern in evaluating the stability of spent fuel. Dissolution of UO 2 is greatly increased in an oxidizing solution because the dissolution is then controlled by the formation of hexavalent uranium. In solutions containing very low oxygen levels (i.e., reducing solutions), oxidation-induced dissolution may be possible via a previously oxidized surface, through exposure to air during storage, or by local oxidants such as O 2 and H 2 O 2 produced from radiolysis of water and radiation-activated UO 2 surfaces. The effects of oxidation not only increase the dissolution rate, but could lead to the disintegration of spent fuel into fine fragments

  11. Investigating Time-Varying Drivers of Grid Project Emissions Impacts

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, Emily L.; Thayer, Brandon L.; Pal, Seemita; Studarus, Karen E.

    2017-11-15

    The emissions consequences of smart grid technologies depend heavily on their context and vary not only by geographical location, but by time of year. The same technology operated to meet the same objective may increase the emissions associated with energy generation for part of the year and decrease emissions during other times. The Grid Project Impact Quantification (GridPIQ) tool provides the ability to estimate these seasonal variations and garner insight into the time-varying drivers of grid project emissions impacts. This work leverages GridPIQ to examine the emissions implications across years and seasons of adding energy storage technology to reduce daily peak demand in California and New York.

  12. An Empirical Investigation of Individual Differences in Time to Learn

    Science.gov (United States)

    Anderson, Lorin W.

    1976-01-01

    Results show that student differences in time-on-task to learn to criterion are alterable and can be minimized over a sequence of learning units given appropriate adaptive learning strategies. (Author/DEP)

  13. Reprocessing of spent plasma

    International Nuclear Information System (INIS)

    Pierini, G.

    1981-01-01

    This invention relates to a process for removing helium and other impurities from a mixture containing deuterium and tritium, a deuterium/tritium mixture when purified in accordance with such a process and, more particularly, to a process for the reprocessing of spent plasma removed from a thermofusion reactor. (U.K.)

  14. A method for investigating relative timing information on phylogenetic trees.

    Science.gov (United States)

    Ford, Daniel; Matsen, Frederick A; Stadler, Tanja

    2009-04-01

    In this paper, we present a new way to describe the timing of branching events in phylogenetic trees. Our description is in terms of the relative timing of diversification events between sister clades; as such it is complementary to existing methods using lineages-through-time plots which consider diversification in aggregate. The method can be applied to look for evidence of diversification happening in lineage-specific "bursts", or the opposite, where diversification between 2 clades happens in an unusually regular fashion. In order to be able to distinguish interesting events from stochasticity, we discuss 2 classes of neutral models on trees with relative timing information and develop a statistical framework for testing these models. These model classes include both the coalescent with ancestral population size variation and global rate speciation-extinction models. We end the paper with 2 example applications: first, we show that the evolution of the hepatitis C virus deviates from the coalescent with arbitrary population size. Second, we analyze a large tree of ants, demonstrating that a period of elevated diversification rates does not appear to have occurred in a bursting manner.

  15. Investigation of the receivability of VLF standard time and frequency ...

    African Journals Online (AJOL)

    This study is on the receivability of some standard time and frequency signals in the VLF range in Zaria, Nigeria. Signal field strengths of various stations were estimated, and a suitable radio receiving system was set up to receive them. Using the assembled receiver, some of the transmissions, including the Omega W/L at ...

  16. Transducer frequency response variations investigated by time reversal calibration

    Czech Academy of Sciences Publication Activity Database

    Kober, Jan; Převorovský, Zdeněk

    2016-01-01

    Roč. 26, č. 2 (2016), A16-A16 ISSN 1213-3825. [Europen Conference on Acoustic Emission Testing /32./. 07.09.2016-09.09.2016, Praha] Institutional support: RVO:61388998 Keywords : calibration * time reversal * transducer * frequency response Subject RIV: BI - Acoustics

  17. Automatic spent fuel ID number reader (I)

    International Nuclear Information System (INIS)

    Tanabe, S.; Kawamoto, H.; Fujimaki, K.; Kobe, A.

    1991-01-01

    An effective and efficient technique has been developed for facilitating identification works of LWR spent fuel stored in large scale spent fuel storage pools of such as processing plants. Experience shows that there are often difficulties in the implementation of operator's nuclear material accountancy and control works as well as safeguards inspections conducted on spent fuel assemblies stored in deep water pool. This paper reports that the technique is realized as an automatic spent fuel ID number reader system installed on fuel handling machine. The ID number reader system consists of an optical sub-system and an image processing sub-system. Thousands of spent fuel assemblies stored in under water open racks in each storage pool could be identified within relatively short time (e.g. within several hours) by using this combination. Various performance tests were carried out on image processing sub-system in 1990 using TV images obtained from different types of spent fuel assemblies stored in various storage pools of PWR and BWR power stations

  18. Spent fuel dry storage in Hungary

    International Nuclear Information System (INIS)

    Buday, G.; Szabo, B.; Oerdoegh, M.; Takats, F.

    1999-01-01

    Paks Nuclear Power Plant is the only NPP in Hungary. It has four WWER-440 type reactor units. Since 1989, approximately 40-50% of the total annual electricity generation of the country has been supplied by this plant. The fresh fuel is imported from Russia. Most of the spent fuel assemblies have been shipped back to Russia. Difficulties with spent fuel transportation to Russia have begun in 1992. Since that time, some of the shipments were delayed, some of them were completely cancelled, thus creating a backlog of spent fuel filling all storage positions of the plant. To provide assurance of the continued operation, Paks NPPs management decided to implement an independent spent fuel storage facility and chose GEC-Althom's MVDS design. The construction of the facility started in February 1995 and the first spent fuel assembly was placed in the store in September 1997. The paper gives an overview of the situation, describing the conditions leading to the construction of the dry storage facility at Paks and its implementation. Finally, some information is given about the new Public Agency for Radioactive Waste Management established this year and responsible for managing the issues related to spent fuel management. (author)

  19. Pyrochemical processing of DOE spent nuclear fuel

    International Nuclear Information System (INIS)

    Laidler, J.J.

    1995-01-01

    A compact, efficient method for conditioning spent nuclear fuel is under development. This method, known as pyrochemical processing, or open-quotes pyroprocessing,close quotes provides a separation of fission products from the actinide elements present in spent fuel and further separates pure uranium from the transuranic elements. The process can facilitate the timely and environmentally-sound treatment of the highly diverse collection of spent fuel currently in the inventory of the United States Department of Energy (DOE). The pyroprocess utilizes elevated-temperature processes to prepare spent fuel for fission product separation; that separation is accomplished by a molten salt electrorefining step that provides efficient (>99.9%) separation of transuranics. The resultant waste forms from the pyroprocess, are stable under envisioned repository environment conditions and highly leach-resistant. Treatment of any spent fuel type produces a set of common high-level waste forms, one a mineral and the other a metal alloy, that can be readily qualified for repository disposal and avoid the substantial costs that would be associated with the qualification of the numerous spent fuel types included in the DOE inventory

  20. Spent fuel workshop'2002

    Energy Technology Data Exchange (ETDEWEB)

    Poinssot, Ch

    2002-07-01

    This document gathers the transparencies of the presentations given at the 2002 spent fuel workshop: Session 1 - Research Projects: Overview on the IN CAN PROCESSES European project (M. Cowper), Overview on the SPENT FUEL STABILITY European project (C. Poinssot), Overview on the French R and D project on spent fuel long term evolution, PRECCI (C. Poinssot); Session 2 - Spent Fuel Oxidation: Oxidation of uranium dioxide single crystals (F. Garrido), Experimental results on SF oxidation and new modeling approach (L. Desgranges), LWR spent fuel oxidation - effects of burn-up and humidity (B. Hanson), An approach to modeling CANDU fuel oxidation under dry storage conditions (P. Taylor); Session 3 - Spent Fuel Dissolution Experiments: Overview on high burnup spent fuel dissolution studies at FZK/INE (A. Loida), Results on the influence of hydrogen on spent fuel leaching (K. Spahiu), Leaching of spent UO{sub 2} fuel under inert and reducing conditions (Y. Albinsson), Fuel corrosion investigation by electrochemical techniques (D. Wegen), A reanalysis of LWR spent fuel flow through dissolution tests (B. Hanson), U-bearing secondary phases formed during fuel corrosion (R. Finch), The near-field chemical conditions and spent fuel leaching (D. Cui), The release of radionuclides from spent fuel in bentonite block (S.S. Kim), Trace actinide behavior in altered spent fuel (E. Buck, B. Hanson); Session 4 - Radiolysis Issues: The effect of radiolysis on UO{sub 2} dissolution determined from electrochemical experiments with {sup 238}Pu doped UO{sub 2} M. Stroess-Gascoyne (F. King, J.S. Betteridge, F. Garisto), doped UO{sub 2} studies (V. Rondinella), Preliminary results of static and dynamic dissolution tests with {alpha} doped UO{sub 2} in Boom clay conditions (K. Lemmens), Studies of the behavior of UO{sub 2} / water interfaces under He{sup 2+} beam (C. Corbel), Alpha and gamma radiolysis effects on UO{sub 2} alteration in water (C. Jegou), Behavior of Pu-doped pellets in brines

  1. Time-resolved spectral investigations of laser light induced microplasma

    Science.gov (United States)

    Nánai, L.; Hevesi, I.

    1992-01-01

    The dynamical and spectral properties of an optical breakdown microplasma created by pulses of different lasers on surfaces of insulators (KCI), metals (Cu) and semiconductors (V 2O 5), have been investigated. Experiments were carried out in air and vacuum using different wavelengths (λ = 0.694μm, type OGM-20,λ = 1.06μm with a home-made laser based on neodymium glass crystal, and λ = 10.6μm, similarly home-made) and pulse durations (Q-switched and free-running regimes). To follow the integral, dynamical and spectral characteristics of the luminous spot of microplasma we have used fast cameras (SFR-2M, IMACON-HADLAND), a high speed spectral camera (AGAT-2) and a spectrograph (STE-1). It has been shown that the microplasma consists of two parts: fast front (peak) with τ≈100 ns and slow front (tail) with τ≈1μs durations. The detonation front speed is of the order of ≈10 5 cm s -1 and follows the temporal dependence of to t0.4. It depends on the composition of the surrounding gas and its pressure and could be connected with quick evaporation of the material investigated (peak) and optical breakdown of the ambient gaseous atmosphere (tail). From the delay in appearance of different characteristic spectral lines of the target material and its gaseous surrounding we have shown that the evolution of the microplasma involves evaporation and ionization of the atoms of the parent material followed by optical breakdown due to the incident and absorbed laser light, together with microplasma expansion.

  2. Encapsulating spent nuclear fuel

    International Nuclear Information System (INIS)

    Fleischer, L.R.; Gunasekaran, M.

    1979-01-01

    A system is described for encapsulating spent nuclear fuel discharged from nuclear reactors in the form of rods or multi-rod assemblies. The rods are completely and contiguously enclosed in concrete in which metallic fibres are incorporated to increase thermal conductivity and polymers to decrease fluid permeability. This technique provides the advantage of acceptable long-term stability for storage over the conventional underwater storage method. Examples are given of suitable concrete compositions. (UK)

  3. Muon Tomography for Imaging and Verification of Spent Fuel

    International Nuclear Information System (INIS)

    Jonkmans, G.; Anghel, V.N.P.; Jewett, C.; Thompson, M.

    2010-01-01

    This paper explores the use of cosmic ray muons to image the content of, and to detect high-Z Special Fissionable Material inside, shielded containers. Cosmic ray muons are a naturally occurring form of radiation, are highly penetrating and exhibit large scattering angles on high-Z materials. Specifically, we investigated how radiographic and tomographic techniques can be effective for non-invasive nuclear material accountancy of spent fuel inside dry storage containers. We show that the tracking of individual muons, as they enter and exit a structure, can potentially improve the accuracy and availability of data on Dry Storage Containers (DSC) used for spent fuel storage at CANDU plants. This could be achieved in near real time, with the potential for unattended and remotely monitored operations. We show that the expected sensitivity to perform material accountancy, in the case of the DSC, exceeds the IAEA detection target for nuclear material accountancy. (author)

  4. Secondary Uranium Phases of Spent Nuclear Fuel. Coffinite, USiO4, and Studtite, UO4.4H2O. Synthesis, Characterization, and Investigations Regarding Phase Stability

    International Nuclear Information System (INIS)

    Labs, Sabrina

    2014-01-01

    The miscibility behavior of the USiO 4 - ThSiO 4 system was investigated. The end members and ten solid solutions U x Th (1-x) SiO 4 with x = 0.12 - 0.92 were successfully synthesized, without formation of other secondary uranium or thorium phases. Lattice parameters of the solid solutions evidently follow Vegard's Law. Investigation of the local structure with EXAFS reveals small differences between U and Th environment attributed to different atomic radii of the metal atoms but no implications for a miscibility gap. The data provided confirms complete miscibility for the system USiO 4 - ThSiO 4 . The structure of the end members was studied in detail with XRD and discussed with special regard to the oxygen positions and the often neglected Si-O bond length. USiO 4 could be obtained without UO 2 impurities and the lattice parameters derived from Rietveld refinement as c = 6.2606(3) Aa and a = 6.9841(3) Aa. The Si-O distance in USiO 4 appears to be 1.64 Aa, which is more reasonable than earlier reported values. Synchrotron X-ray powder diffraction pattern and Raman spectra of synthetic coffinite, USiO 4 , were obtained for pressures up to 35 GPa and 18 GPa, respectively. From the changes in the diffraction pattern it can be concluded that USiO 4 undergoes a first order phase transition from zircon-type (space group I 4 1 /amd) to scheelite-type structure (space group I 4 1 /a) at ∼ 15 GPa and room-temperature. Contrary to earlier reports, the data indicates that this transition is completely reversible upon pressure release. Pressure dependencies of the Raman modes for the zircon structured phase are larger than those reported for hafnon, HfSiO 4 , and zircon, ZrSiO 4 , indicating that coffinite, USiO 4 , is more compressible than these orthosilicates. Bulk moduli fitted from the p-V data for the zircon-type and scheelite-type USiO 4 phase are compared to those known to literature for other MSiO 4 (M = U, Hf, Zr) compounds. The bulk modulus for zircon

  5. Time spent on health-related activities by senior Australians with chronic diseases: what is the role of multimorbidity and comorbidity?

    Science.gov (United States)

    Islam, M Mofizul; McRae, Ian S; Yen, Laurann; Jowsey, Tanisha; Valderas, Jose M

    2015-06-01

    To examine the effect of various morbidity clusters of chronic diseases on health-related time use and to explore factors associated with heavy time burden (more than 30 hours/month) of health-related activities. Using a national survey, data were collected from 2,540 senior Australians. Natural clusters were identified using cluster analysis and clinical clusters using clinical expert opinion. We undertook a set of linear regressions to model people's time use, and logistic regressions to model heavy time burden. Time use increases with the number of chronic diseases. Six of the 12 diseases are significantly associated with higher time use, with the highest effect for diabetes followed by depression; 18% reported a heavy time burden, with diabetes again being the most significant disease. Clusters and dominant comorbid groupings do not contribute to predicting time use or time burden. Total number of diseases and specific diseases are useful determinants of time use and heavy time burden. Dominant groupings and disease clusters do not predict time use. In considering time demands on patients and the need for care co-ordination, care providers need to be aware of how many and what specific diseases the patient faces. © 2015 Public Health Association of Australia.

  6. Is spending time in screen-based sedentary behaviors associated with less physical activity: a cross national investigation

    Directory of Open Access Journals (Sweden)

    Iannotti Ronald J

    2010-05-01

    Full Text Available Abstract Background In Australia and the USA, national guidelines exist for limiting children's screen-exposure to two hours per day. This study aims to determine whether exceeding the suggested guidelines for screen-based sedentary behavior is associated with reduced levels of physical activity across different geographical regions. Methods Data material were taken from the 2005/2006 survey of "Health Behaviour in School-aged Children (HBSC study; A WHO cross-National Survey". Data were collected through questionnaires from 11-,13- and,15- year olds. The final sample included 200,615 adolescents from 39 different countries in Europe and North America. Gender and country stratified analyses regressed time spent in leisure-time vigorous physical activity (VPA and days of 60 minutes moderate to vigorous physical activity (MVPA on time spent in screen-based sedentary behaviors. To simplify interpretation, the estimates from each country were pooled using a meta-analytic procedure. Results Exceeding 2 hrs of daily total screen-time was negatively associated with MVPA for both boys and girls, and with VPA for girls. When investigating the different types of screen-based behaviors separately, exceeding 2 hrs daily of TV viewing was associated with less MVPA for both boys and girls and less VPA for girls. Gaming was associated with less MVPA and VPA for boys, and non-gaming computer use was associated with higher levels of VPA for both genders. Stronger negative associations between physical activity and screen-based sedentary behaviors were found in countries where mean levels of physical activity were relatively high. The association between physical activity and sedentary behavior was not significantly associated with national levels of screen-based sedentary behaviors. Conclusions The displacement mechanism does not appear to be universal across countries. On a national level, negative associations between physical activity and screen

  7. The development of spent fuel storage process equipment

    International Nuclear Information System (INIS)

    Yoon, Wan Ki; Kim, Ho Dong; Kim, Ki Joon; Kim, Bum Hoe

    1992-02-01

    A nuclear material accounting system were designed to track the transitions of nuclear materials at the spent-fuel technology research facility. It is embedded in a distributed control system real-time structure of the system gives timely on-line accountancy. And performance of AC servo motor with fuzzy logic control and its applicability to spent fuel management were experimentally evaluated. (Author)

  8. Time Spent on Dedicated Patient Care and Documentation Tasks Before and After the Introduction of a Structured and Standardized Electronic Health Record

    NARCIS (Netherlands)

    Joukes, Erik; Abu-Hanna, Ameen; Cornet, Ronald; de Keizer, Nicolette F.

    2018-01-01

    Physicians spend around 35% of their time documenting patient data. They are concerned that adopting a structured and standardized electronic health record (EHR) will lead to more time documenting and less time for patient care, especially during consultations.  This study measures the effect of the

  9. Spent fuel storage requirements

    International Nuclear Information System (INIS)

    Fletcher, J.

    1982-06-01

    Spent fuel storage requirements, as projected through the year 2000 for U.S. LWRs, were calculated using information supplied by the utilities reflecting plant status as of December 31, 1981. Projections through the year 2000 combined fuel discharge projections of the utilities with the assumed discharges of typical reactors required to meet the nuclear capacity of 165 GWe projected by the Energy Information Administration (EIA) for the year 2000. Three cases were developed and are summarized. A reference case, or maximum at-reactor (AR) capacity case, assumes that all reactor storage pools are increased to their maximum capacities as estimated by the utilities for spent fuel storage utilizing currently licensed technologies. The reference case assumes no transshipments between pools except as currently licensed by the Nuclear Regulatory Commission (NRC). This case identifies an initial requirement for 13 MTU of additional storage in 1984, and a cumulative requirement for 14,490 MTU additional storage in the year 2000. The reference case is bounded by two alternative cases. One, a current capacity case, assumes that only those pool storage capacity increases currently planned by the operating utilities will occur. The second, or maximum capacity with transshipment case, assumes maximum development of pool storage capacity as described above and also assumes no constraints on transshipment of spent fuel among pools of reactors of like type (BWR, PWR) within a given utility. In all cases, a full core discharge capability (full core reserve or FCR) is assumed to be maintained for each reactor, except that only one FCR is maintained when two reactors share a common pool. For the current AR capacity case the indicated storage requirements in the year 2000 are indicated to be 18,190 MTU; for the maximum capacity with transshipment case they are 11,320 MTU

  10. Preliminary Calculation on a Spent Fuel Pool Accident using GOTHIC

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jaehwan; Choi, Yu Jung; Hong, Tae Hyub; Kim, Hyeong-Taek [KHNP-CRI, Daejeon (Korea, Republic of)

    2015-10-15

    The probability of an accident happening at the spent fuel pool was believed to be quite low until the 2011 Fukushima accident occurred. Notably, large amount of spent fuel are normally stored in the spent fuel pool for a long time compared to the amount of fuel in the reactor core and the total heat released from the spent fuel is high enough to boil the water of the spent fuel pool when the cooling system does not operate. In addition, the enrichment and the burnup of the fuel have both increased in the past decade and heat generation from the spent fuel thereby has also increased. The failure of the cooling system at the spent fuel pool (hereafter, a loss-of-cooling accident) is one of the principal hypothetical causes of an accident that could occur at the spent fuel pool. In this paper, the preliminary calculation of a loss-of-cooling accident was performed. In this paper, the preliminary calculation of a loss-of cooling accident was performed with GOTHIC. The calculation results show boiling away of water in the spent fuel pool due to the loss-of-cooling accident and similar thermal performance of the spent fuel pool with previous research results.

  11. Intermodal transfer of spent fuel

    International Nuclear Information System (INIS)

    Neuhauser, K.S.; Weiner, R.F.

    1993-01-01

    This paper discusses RADTRAN calculational models and parameter values for describing dose to workers during incident-free ship-to-truck transfer of spent fuel. Data obtained during observation of the offloading of research reactor spent fuel at Newport News Terminal in the Port of Hampton Roads, Virginia, are described. These data include estimates of exposure times and distances for handlers, inspectors, and other workers during offloading and overnight storage. Other workers include crane operators, scale operators, security personnel, and truck drivers. The data are compared to the default data in RADTRAN 4, and the latter are found to be conservative. The casks were loaded under IAEA supervision at their point of origin, and three separate radiological inspections of each cask were performed at the entry to the port (Hampton Roads) by the U.S. Coast Guard, the state of Virginia, and the shipping firm. As a result of the international standardization of containerized cargo handling in ports around the world, maritime shipment handling is particularly uniform. Thus, handler exposure parameters will be relatively constant for ship-truck and ship-rail transfers at ports throughout the world. Inspectors' doses are expected to vary because of jurisdictional considerations. The results of this study should be applicable to truck-to-rail transfers. (author)

  12. Mobility of U, Np, Pu, Am and Cm from spent nuclear fuel into bentonite clay

    International Nuclear Information System (INIS)

    Ramebaeck, H.; Skaalberg, M.; Eklund, U.B.; Kjellberg, L.; Werme, L.

    1998-01-01

    The mobility of uranium, neptunium, plutonium, americium and curium from spent nuclear fuel (UO 2 ) into compacted bentonite was studied. Pieces of spent BWR UO 2 fuel was embedded in a compacted bentonite clay/low saline synthetic groundwater system. After a contact time of six years the bentonite was sliced into 0.1 mm thick slices and analysed for its content of actinides. Radiometric as well as inductively coupled plasma mass spectrometry (ICP-MS) were used for the analysis. The influence on the mobility by the addition of metallic iron, metallic copper and vivianite (Fe(II)-mineral) to the bentonite clay was investigated. The results show a low mobility of actinides in bentonite clay. Except for uranium the mobility of the other actinides could, after six years of diffusion time, only be detected less than 1 mm from the spent fuel. (orig.)

  13. Transportation capabilities study of DOE-owned spent nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Clark, G.L.; Johnson, R.A.; Smith, R.W. [Packaging Technology, Inc., Tacoma, WA (United States); Abbott, D.G.; Tyacke, M.J. [Lockheed Idaho Technologies Co., Idaho Falls, ID (United States)

    1994-10-01

    This study evaluates current capabilities for transporting spent nuclear fuel owned by the US Department of Energy. Currently licensed irradiated fuel shipping packages that have the potential for shipping the spent nuclear fuel are identified and then matched against the various spent nuclear fuel types. Also included are the results of a limited investigation into other certified packages and new packages currently under development. This study is intended to support top-level planning for the disposition of the Department of Energy`s spent nuclear fuel inventory.

  14. Encapsulation technology of MR6 spent fuel and quality analysis of the EK-10 and WWR-SM spent fuel stored more than 30 years in wet conditions

    Energy Technology Data Exchange (ETDEWEB)

    Borek-Kruszewska, E.; Bykowski, W.; Chwaszczewski, S.; Czajkowski, W.; Madry, M. [Institute of Atomic Energy, Otwock -Swierk (Poland)

    2002-07-01

    The research reactor MARIA has been in operation for more than twenty years and all the spent fuel assemblies used since the first commissioning of the reactor are stored in wet facility on site. The present paper deals with the spent fuel MR-6 encapsulation technology in MARIA reactor. The encapsulated spent MR-6 fuel will be stored under water in the same pool unless some other solution is available. The capsules made of stainless steel are capable to accommodate one MR-6 fuel assembly. The encapsulation process is performed in the hot cell by the MARIA reactor. The spent fuel having its leg cut off is loaded to the transport cylinder manually and next transferred to a trolley. The trolley is moving to a position directly below the entrance to the hot cell and the spent fuel is entering the hot cell. The spent fuel assembly is then put into the drying cell. Dried out spent fuel is moved into the capsule mounted on the grip of the machine. Next, the capsule lid is pressed in and welded. After the leak test and filling up with helium the capsule returns from the hot cell to the pool. The hermetic capsule is sunk back into the water and positioned in the separator . The results presented earlier show, that the limiting time of WWR-SM and Ek-10 type spent fuel residence in wet storage is about 40-45 years. Therefore, the systematic quality investigation of all Ek-10 fuel elements and WWR-SM fuel assemblies discharged from EWA reactor in the period of 1959-1969 was performed. Altogether, about 2500 Ek-10 fuel elements and 47 WWR-SM fuel assemblies were investigated. The results of these investigations are presented in the present work. The sipping test, visual investigation and ultrasonic techniques were used for that purpose. The radioactive isotope Cs-137 was used as the indicator of fission product release from the fuel assembly. Taking into account the value of Cs-137 release from damaged WWR-SM fuel assembly the criteria of damaged fuel assembly were proposed. It

  15. Adolescents who engage in active school transport are also more active in other contexts: A space-time investigation.

    Science.gov (United States)

    Stewart, Tom; Duncan, Scott; Schipperijn, Jasper

    2017-01-01

    Although active school travel (AST) is important for increasing moderate-to-vigorous physical activity (MVPA), it is unclear how AST is related to context-specific physical activity and non-school travel. This study investigated how school travel is related to physical activity and travel behaviours across time- and space-classified domains. A total of 196 adolescents wore a Global Positioning System receiver and an accelerometer for 7 days. All data were classified into one of four domains: home, school, transport, or leisure. Generalized linear mixed models were used to compare domain-specific PA and non-school trips between active and passive school travellers. Active travellers accumulated 13 and 14 more min of MVPA on weekdays and weekend days, respectively. They also spent 15min less time in vehicular travel during non-school trips, and accrued an additional 9min of MVPA while walking on weekend days. However, those with no AST still achieved most of their MVPA in the transport domain. AST is related to out-of-school physical activity and transportation, but transport is also important for those who do not use AST. As such, future studies should consider overall mobility and destinations other than school when assessing travel and physical activity behaviours. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Using prospect theory to investigate the low marginal value of travel time for small time changes

    DEFF Research Database (Denmark)

    Hjorth, Katrine; Fosgerau, Mogens

    2012-01-01

    A common finding in stated preference studies that measure the value of travel time (VTT) is that the measured VTT increases with the size of the time change considered, in conflict with standard neoclassical economic theory. We present a new test of a possible explanation for the phenomenon...... that builds on the diminishing or constant sensitivity of the value functions in prospect theory.We use stated preference data with trade-offs between travel time and money that provide separate identification of the degrees of diminishing sensitivity for time and money gains and losses. This enables us...

  17. Spent fuel reprocessing method

    International Nuclear Information System (INIS)

    Shoji, Hirokazu; Mizuguchi, Koji; Kobayashi, Tsuguyuki.

    1996-01-01

    Spent oxide fuels containing oxides of uranium and transuranium elements are dismantled and sheared, then oxide fuels are reduced into metals of uranium and transuranium elements in a molten salt with or without mechanical removal of coatings. The reduced metals of uranium and transuranium elements and the molten salts are subjected to phase separation. From the metals of uranium and transuranium elements subjected to phase separation, uranium is separated to a solid cathode and transuranium elements are separated to a cadmium cathode by an electrolytic method. Molten salts deposited together with uranium to the solid cathode, and uranium and transuranium elements deposited to the cadmium cathode are distilled to remove deposited molten salts and cadmium. As a result, TRU oxides (solid) such as UO 2 , Pu 2 in spent fuels can be reduced to U and TRU by a high temperature metallurgical method not using an aqueous solution to separate them in the form of metal from other ingredients, and further, metal fuels can be obtained through an injection molding step depending on the purpose. (N.H.)

  18. Spent fuel interim storage

    International Nuclear Information System (INIS)

    Bilegan, Iosif C.

    2003-01-01

    The official inauguration of the spent fuel interim storage took place on Monday July 28, 2003 at Cernavoda NNP. The inaugural event was attended by local and central public authority representatives, a Canadian Government delegation as well as newsmen from local and central mass media and numerous specialists from Cernavoda NPP compound. Mr Andrei Grigorescu, State Secretary with the Economy and Commerce Ministry, underlined in his talk the importance of this objective for the continuous development of nuclear power in Romania as well as for Romania's complying with the EU practice in this field. Also the excellent collaboration between the Canadian contractor AECL and the Romanian partners Nuclear Montaj, CITON, UTI, General Concret in the accomplishment of this unit at the planned terms and costs. On behalf of Canadian delegation, spoke Minister Don Boudria. He underlined the importance which the Canadian Government affords to the cooperation with Romania aiming at specific objectives in the field of nuclear power such as the Cernavoda NPP Unit 2 and spent fuel interim storage. After traditional cutting of the inaugural ribbon by the two Ministers the festivities continued on the Cernavoda NPP Compound with undersigning the documents regarding the project completion and a press conference

  19. Spent fuel storage rack

    International Nuclear Information System (INIS)

    Kurokawa, Hideaki; Kumagaya, Naomi; Oda, Masashi; Matsuda, Masami; Maruyama, Hiromi; Yamanaka, Tsuneyasu.

    1997-01-01

    The structure of a spent fuel storage rack is determined by the material, thickness, size of square cylindrical tubes (the gap between spent fuel assemblies and the square cylindrical tubes) and pitch of the arrangement (the gap between each of the square cylindrical tubes). In the present invention, the thickness and the pitch of the arrangement of the square tubes are optimized while evaluating subcriticality. Namely, when the sum of the thickness of the water gap at the outer side (the pitch of arrangement of the cylindrical tubes) and the thickness of the cylindrical tubes is made constant, the storage rack is formed by determining the thickness of the cylindrical tubes which is smaller than the optimum value among the combination of the thickness of the water gap at the outer side and that of the cylindrical tube under the effective multiplication factor to be performed. Then, the weight of the rack can be reduced, and the burden of the load on the bottom of the pool can be reduced. Further, the amount of the constitutional materials of the rack itself can be reduced thereby capable of reducing the cost for the materials of the rack. (T.M.)

  20. Storing the world's spent nuclear fuel

    International Nuclear Information System (INIS)

    Barkenbus, J.N.; Weinberg, A.M.; Alonso, M.

    1985-01-01

    Given the world's prodigious future energy requirements and the inevitable depletion of oil and gas, it would be foolhardy consciously to seek limitations on the growth of nuclear power. Indeed, the authors continue to believe that the global nuclear power enterprise, as measured by installed reactor capacity, can become much larger in the future without increasing proliferation risks. To accomplish this objective will require renewed dedication to the non-proliferation regime, and it will require some new initiatives. Foremost among these would be the establishment of a spent fuel take-back service, in which one or a few states would retrieve spent nuclear fuel from nations generating it. The centralized retrieval of spent fuel would remove accessible plutonium from the control of national leaders in non-nuclear-weapons states, thereby eliminating the temptation to use this material for weapons. The Soviets already implement a retrieval policy with the spent fuel generated by East European allies. The authors believe that it is time for the US to reopen the issue of spent-fuel retrieval, and thus to strengthen its non-proliferation policies and the nonproliferation regime in general. 7 references

  1. Using prospect theory to investigate the low value of travel time for small time changes

    DEFF Research Database (Denmark)

    Hjorth, Katrine; Fosgerau, Mogens

    A common finding in stated preference studies that measure the value of travel time (VTT), is that the measured per-minute VTT increases with the size of the time change considered, in conflict with standard neoclassical theory. The current paper tests prospect theory as a possible explanation......: More specifically, whether the phenomenon is generated by preferences being reference-dependent and exhibiting diminishing sensitivity for gains and losses, with a stronger degree of diminishing sensitivity for money than for travel time. We use stated preference data with trade-offs between travel...... time and money that pro- vide identification of the degrees of diminishing sensitivity for time and money gains and losses, thus enabling us to test and potentially falsify the prospect theory explanation. We apply a discrete choice model, in which choice depends on a reference-free value of travel...

  2. Neutron intensity of fast reactor spent fuel

    Energy Technology Data Exchange (ETDEWEB)

    Takamatsu, Misao; Aoyama, Takafumi [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center

    1998-03-01

    Neutron intensity of spent fuel of the JOYO Mk-II core with a burnup of 62,500 MWd/t and cooling time of 5.2 years was measured at the spent fuel storage pond. The measured data were compared with the calculated values based on the JOYO core management code system `MAGI`, and the average C/E approximately 1.2 was obtained. It was found that the axial neutron intensity didn`t simply follow the burnup distribution, and the neutron intensity was locally increased at the bottom end of the fuel region due to an accumulation of {sup 244}Cm. (author)

  3. Significance of campaigned spent fuel shipments

    International Nuclear Information System (INIS)

    Doman, J.W.; Tehan, T.E.

    1993-01-01

    Operational experience associated with spent fuel or irradiated hardware shipments to or from the General Electric Morris Facility is presented. The following specific areas are addressed: Problems and difficulties associated with meeting security and safeguard requirements of 10 CFR Part 73; problems associated with routing via railroad; problems associated with scheduling and impact on affected parties when a shipment is delayed or cancelled; and impact on training when shipments spread over many years. The lessons learned from these experiences indicate that spent fuel shipments are best conducted in dedicated open-quotes campaignsclose quotes that concentrate as much consecutive shipping activity as possible into one continuous time frame

  4. Method of processing spent fuel cladding tubes

    International Nuclear Information System (INIS)

    Nakatsuka, Masafumi; Ouchi, Atsuhiro; Imahashi, Hiromichi.

    1986-01-01

    Purpose: To decrease the residual activity of spent fuel cladding tubes in a short period of time and enable safety storage with simple storage equipments. Constitution: Spent fuel cladding tubes made of zirconium alloys discharged from a nuclear fuel reprocessing step are exposed to a grain boundary embrittling atmosphere to cause grain boundary destruction. This causes grain boundary fractures to the zirconium crystal grains as the matrix of nuclear fuels and then precipitation products precipitated to the grain boundary fractures are removed. The zirconium constituting the nuclear fuel cladding tube and other ingredient elements contained in the precipitation products are separated in this removing step and they are separately stored respectively. As a result, zirconium constituting most part of the composition of the spent nuclear fuel cladding tubes can be stored safely at a low activity level. (Takahashi, M.)

  5. Status of spent fuel shipping cask development

    International Nuclear Information System (INIS)

    Hall, I.K.; Hinschberger, S.T.

    1989-01-01

    This paper discusses how several new-generation shopping cask systems are being developed for safe and economical transport of commercial spent nuclear fuel and other radioactive wastes for the generating sites to a federal geologic repository or monitored retrievable storage (MRS) facility. Primary objectives of the from-reactor spent fuel cask development work are: to increase cask payloads by taking advantage of the increased at-reactor storage time under the current spent fuel management scenario, to facilitate more efficient cask handling operations with reduced occupational radiation exposure, and to promote standardization of the physical interfaces between casks and the shipping and receiving facilities. Increased cask payloads will significantly reduce the numbers of shipments, with corresponding reductions in transportation costs and risks to transportation workers, cask handling personnel, and the general public

  6. A summary of INSITE activities in tracking SKB's spent fuel repository site investigations from 2002-2009 and of advice provided to the regulatory authorities on the status of site understanding at the end of the surface-based investigations

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, Neil (Chapman Consulting (Switzerland)); Bath, Adrian (Intellisci Ltd, (United Kingdom)); Geier, Joel (Clearwater Hardrock Consulting (United States)); Ove Stephansson (Steph Rock Consulting AB (Sweden)); Tiren, Sven (Geosigma (Sweden)); Tsang, Chin-Fu (Berkeley Geohydrophysics SP (United States))

    2010-11-15

    SSM and its predecessor SKI employed a team of earth scientists who followed and reviewed SKB's investigations of the potential spent nuclear fuel repository sites at Forsmark and Laxemar. This group was named INSITE (INdependent Site Investigation Tracking and Evaluation) and began its work in 2002 and completed its task with the review of the final versions SKB's site descriptive models, SDM-Site, in 2009. This report is a summary of INSITE's work over the eight-and-a-half year period of the site investigations and the lead-in and the wind-down to the work. It is intended to provide an outline and a record of how INSITE has worked and how its advice was generated and provided to SKI and, latterly, to SSM. Together with all the other documentation generated by INSITE, this report is intended to support the regulatory review of SKB's licence application for a spent nuclear fuel repository

  7. Predicting fissile content of spent nuclear fuel assemblies with the Passive Neutron Albedo Reactivity technique and Monte Carlo code emulation

    International Nuclear Information System (INIS)

    Conlin, Jeremy Lloyd; Tobin, Stephen J.

    2011-01-01

    There is a great need in the safeguards community to be able to nondestructively quantify the mass of plutonium of a spent nuclear fuel assembly. As part of the Next Generation of Safeguards Initiative, we are investigating several techniques, or detector systems, which, when integrated, will be capable of quantifying the plutonium mass of a spent fuel assembly without dismantling the assembly. This paper reports on the simulation of one of these techniques, the Passive Neutron Albedo Reactivity with Fission Chambers (PNAR-FC) system. The response of this system over a wide range of spent fuel assemblies with different burnup, initial enrichment, and cooling time characteristics is shown. A Monte Carlo method of using these modeled results to estimate the fissile content of a spent fuel assembly has been developed. A few numerical simulations of using this method are shown. Finally, additional developments still needed and being worked on are discussed. (author)

  8. Spent fuel: prediction model development

    International Nuclear Information System (INIS)

    Almassy, M.Y.; Bosi, D.M.; Cantley, D.A.

    1979-07-01

    The need for spent fuel disposal performance modeling stems from a requirement to assess the risks involved with deep geologic disposal of spent fuel, and to support licensing and public acceptance of spent fuel repositories. Through the balanced program of analysis, diagnostic testing, and disposal demonstration tests, highlighted in this presentation, the goal of defining risks and of quantifying fuel performance during long-term disposal can be attained

  9. Spent fuel. Dissolution and oxidation

    International Nuclear Information System (INIS)

    Grambow, B.

    1989-03-01

    Data from studies of the low temperature air oxidation of spent fuel were retrieved in order to provide a basis for comparison between the mechanism of oxidation in air and corrosion in water. U 3 O 7 is formed by diffusion of oxygen into the UO 2 lattice. A diffusion coefficient of oxygen in the fuel matric was calculated for 25 degree C to be in the range of 10 -23 to 10 -25 m 2 /s. The initial rates of U release from spent fuel and from UO 2 appear to be similar. The lowest rates (at 25 degree c >10 -4 g/(m 2 d)) were observed under reducing conditions. Under oxidizing conditions the rates depend mainly of the nature and concentraion of the oxidant and/or on corbonate. In contact with air, typical initial rates at room temperature were in the range between 0.001 and 0.1 g/(m 2 d). A study of apparent U solubility under oxidizing conditions was performed and it was suggested that the controlling factor is the redox potential at the UO 2 surface rather than the E h of the bulk solution. Electrochemical arguments were used to predict that at saturation, the surface potential will eventually reach a value given by the boundaries at either the U 3 O 7 /U 3 O 8 or the U 3 O 7 /schoepite stability field, and a comparison with spent fuel leach data showed that the solution concentration of uranium is close to the calculated U solubility at the U 3 O 7 /U 3 O 8 boundary. The difference in the cumulative Sr and U release was calculated from data from Studsvik laboratory. The results reveal that the rate of Sr release decreases with the square root of time under U-saturated conditions. This time dependence may be rationalized either by grain boundary diffusion or by diffusion into the fuel matrix. Hence, there seems to be a possibility of an agreement between the Sr release data, structural information and data for oxygen diffusion in UO 2 . (G.B.)

  10. What Do Teachers Perceive as the Most Important Use of Reading Time?

    Science.gov (United States)

    McNinch, George H.; Schaffer, Gary L.; Cambell, Patricia; Rakes, Sondra

    1999-01-01

    Considers what teachers perceive as the appropriate time allocation among the distinct instructional areas during a typical reading session. Evaluates 58 teachers using a questionnaire that investigates four questions concerning ideal use of instruction time. Suggests that time spent reading must exceed time spent talking and writing about reading…

  11. Learning Style versus Time Spent Studying and Career Choice: Which Is Associated with Success in a Combined Undergraduate Anatomy and Physiology Course?

    Science.gov (United States)

    Farkas, Gary J.; Mazurek, Ewa; Marone, Jane R.

    2016-01-01

    The VARK learning style is a pedagogical focus in health care education. This study examines relationships of course performance vs. VARK learning preference, study time, and career plan among students enrolled in an undergraduate anatomy and physiology course at a large urban university. Students (n?=?492) from the fall semester course completed…

  12. an investigation of time installation of x surface me estigation of time ...

    African Journals Online (AJOL)

    eobe

    The direct costs of the project are activity based co. They generally ... ies have been done on the Time-Cost-Risk trade-off problem off problem imization model for TCRTP imization model for TCRTP based on some realistic .... A solution is Pareto optimal, if there is no feasible .... difficult problems facing management in most.

  13. Spent fuel management in South Africa

    International Nuclear Information System (INIS)

    Bredell, P.J.; Stott, A.K.

    1998-01-01

    Eskom, the South African utility, operates one of the largest electricity networks in the world. However, only 6% of the South African generating capacity is nuclear; the remainder is coal fired and hydroelectric. The nuclear component consists of the Koeberg Nuclear Power Plant, comprising two French supplied PWRs of 920 MWe each, situated approximately 45 kilometres from cape Town. Construction started in 1976 and the two reactors reached criticality in 1984 and 1985 respectively. South Africa also has an Oak Ridge type research reactor, called SAFARI, operated by the South African Atomic Energy Corporation (AEC) at their Pelindaba site near Pretoria. This research reactor was commissioned in 1965, and has been in operation ever since. South Africa has a National Radioactive Waste Disposal facility called Vaalputs, some 600 km north of Cape Town. The facility, operated by AEC, is presently licensed only for the disposal of low and intermediate radioactive level wastes. Vaalputs offers unique features as a potential interim spent fuel storage and final disposal site, such as favorable geology (granite), low seismicity, low population density, remoteness from industrial centres and and conditions. Therefore, this site has been investigated by the AEC as a potential interim spent fuel storage site, but has not yet been licensed for this purpose. Hence, all spent fuel is currently stored on the two sites at Koeberg and Pelindaba respectively. The spent fuel storage pools at Koeberg have recently been enlarged to accommodate the lifetime spent fuel arisings of the plant. Since late 1997, the Safari spent fuel is stored in a pipe storage facility, constructed away from the reactor on the Pelindaba site. (author)

  14. Joint Russian-Norwegian expedition to the dumping sites for radioactive waste and spent nuclear fuel in the Stepovogo fjord of the Kara sea, August - September 2012: investigations performed and main results

    Energy Technology Data Exchange (ETDEWEB)

    Nikitin, Aleksandr; Shershakov, Viacheslav; Valetova, Nailja; Petrenko, Galina; Katrich, Ivan; Fedorova, Anastasia [Research and Production Association ' Typhoon' , 249038, Obninsk, Kaluga Region (Russian Federation); Kazennov, Alexey [National Research Centre ' Kurchatov Institute' , Moscow (Russian Federation); Lind, Bjorn; Gwynn, Justin; Rudjord, Anne Liv [Norwegian Radiation Protection Authority, Oesteraas (Norway); Heldal, Hilde Elise [Institute of Marine Research, Bergen (Norway); Blinova, Oxana; Osvath, Iolanda; Levy, Isabelle; Bartocci, Jean; Khanh Pham, Mai; Sam, Adam; Nies, Hartmut [IAEA-MEL (Monaco); Grishin, Denis [Krylov State Research Centre, St. Petersburg (Russian Federation); Salbu, Brit; Ole- Christian, Lind; Teien, Hans-Cristian [Norwegian University of Life Sciences, Aas (Norway); Sidhu, Rajdeep Singh; Straalberg, Elisabeth [Institute for Energy Technology, Kjeller (Norway); Logoyda, Igor [State Scientific Centre ' Yuzhmorgeologiya' , Gelendzhik (Russian Federation)

    2014-07-01

    Stepovogo fjord, located on the Eastern coast of Novaya Zemlya, is one of the most important former Soviet Union dumping sites for radioactive waste in the Kara Sea. In addition to some 2000 dumped containers with conventional radioactive wastes, the nuclear submarine K-27 was dumped in Stepovogo fjord with two reactors loaded with spent nuclear fuel (SNF).Joint Russian and Norwegian surveys of the marine environment in Stepovogo fjord were first conducted in 1993 and 1994. In accordance with the working plan of the Joint Russian-Norwegian Expert Group on the Investigation of Radioactive Contamination in the Northern Areas, a follow up expedition into the radioecological status of Stepovogo fjord was carried out in August and September of 2012 onboard the R.V. 'Ivan Petrov' of the Roshydromet Northern Department. Investigations carried out in Stepovogo fjord during the expedition included: Sonar surveys, ROV inspections and in situ gamma measurements of the dumped nuclear submarine K-27 and dumped containers with radioactive waste Sampling of seawater, bottom sediments and marine biota. Results of the analysis of marine environmental samples performed by Russia, Norway and the IAEA, are presented and discussed in the paper. Preliminary measurements on surface sediments and water samples showed that the level of {sup 137}Cs contamination was generally low. However, slightly enhanced levels of {sup 137}Cs were detected in bottom seawater and sediment collected in the area with dumped containers. Measurements taken around the dumped nuclear submarine K-27 did not indicate any leakage of radioactive substances from the submarine. A similar picture for the level of radioactive contamination in Stepovogo fjord was observed in the first joint Russian-Norwegian expedition in 1993-94. (authors)

  15. An Investigation of Time-Distortion Utilizing Space-Time/Field Relationships

    CERN Document Server

    Park, T

    1990-01-01

    EPR communication and backward-in-time information communication described in nonlocal quantum mechanics theories may prove a great problem within the confines of relativity, since the theory of Relativity maintains that nothing can possibly accelerate at or beyond the speed of light constant (c). However, according to the Grangier-Rogers-Aspect EPR experimental results, the theoretical results of Garcia, Ibarguen and Plebanski, as well as the mathematically consistent nonlinear evolutionary equations of Weinberg, Polchinski, Gisin and Czachor, EPR photon-to-photon information communication or FTL information communication is theoretically possible. Therefore, the purpose of this paper is to propose that normal concepts of time and space breakdown and attain null values as the speed of light constant is matched and then surpassed where FTL by several million fold is possible due to the nullification of the effects of mass (m). For in the new physics, both the force of gravity (F = mg) and the centrifugal forc...

  16. Corrosion of research reactor aluminium-clad spent fuel in water-chemical and microbiological influenced

    International Nuclear Information System (INIS)

    Maksin, T.N.; Dobrijevic, R.P.; Idjakovic, Z.E.; Pesic, M.P.

    2002-01-01

    Spent fuel resulting from 25 years of operating research reactor RA at the Vinca Institute is presently all stored in the temporary spent fuel storage pool. It has been left in the ambient temperature and humidity for more then fifteen years so intensive corrosion processes were notice. We have spent fuel pools under control, after first research coordination meeting (RCM), of the first CRP, by monitoring of physical and chemical parameters of water in the pools, including temperature, pH-factor, electrical conductivity, mass concentration of corrosion products in the water and mud, mass concentration of relevant ions etc. The rack of standard corrosion coupons, was given at that time, has been in poor quality water for six years. We pick up rack assembly from basin and analysed. The results of this investigation are present in this article. (author)

  17. O tempo na trajetória das famílias que buscam a justiça Time spent by families in search for justice

    Directory of Open Access Journals (Sweden)

    Marcia Regina Ribeiro dos Santos

    2007-01-01

    Full Text Available Estudar o tempo em sua multiplicidade de entendimentos é importante para os profissionais psicossociais na medida em que a experiência de atuação com famílias em litígio e que buscam a justiça exige celeridade. Como conciliar os diferentes tempos do indivíduo, da família, da lei, do juiz, do profissional nas decisões sobre a família? A sociedade exige que a Justiça seja feita de forma mais rápida, mas os prazos estabelecidos em lei nem sempre são compatíveis com o tempo "exigido" pelo indivíduo ou pela sociedade. Por outro lado os prazos processuais têm a função de proteger a sociedade em seus anseios.To study time, in its multiplicity of understanding, is important for psychosocial professionals inasmuch as the experience of dealing with families who are in dispute and search for Justice demand celerity. How to reconcile the different times of the individual, the family, the law, the judge and the professional in the decisions about the family? Society demands that Justice is made in the fastest way but the terms stablished by law are not always compatible with the term "required" by the individual or the society. On the other hand, the process terms have to protect the society in its spectations.

  18. Department of Energy report on fee for spent nuclear fuel storage and disposal services

    International Nuclear Information System (INIS)

    1980-10-01

    Since the July 1978 publication of an estimated fee for storage and disposal, several changes have occurred in the parameters which impact the spent fuel fee. DOE has mounted a diversified program of geologic investigations that will include locating and characterizing a number of potential repository sites in a variety of different geologic environments with diverse rock types. As a result, the earliest operation date of a geologic repository is now forecast for 1997. Finally, expanded spent fuel storage capabilities at reactors have reduced the projected quantities of fuel to be stored and disposed of. The current estimates for storage and disposal are presented. This fee has been developed from DOE program information on spent fuel storage requirements, facility availability, facility cost estimates, and research and development programs. The discounted cash flow technique has used the most recent estimates of cost of borrowing by the Federal Government. This estimate has also been used in calculating the Federal charge for uranium enrichment services. A prepayment of a percentage of the storage portion of the fee is assumed to be required 5 years before spent fuel delivery. These funds and the anticipated $300 million in US Treasury borrowing authority should be sufficient to finance the acquisition of storage facilities. Similarly, a prepayment of a percentage of the disposal portion would be collected at the same time and would be used to offset disposal research and development expenditures. The balance of the storage and disposal fees will be collected upon spent fuel delivery. If disposal costs are different from what was estimated, there will be a final adjustment of the disposal portion of the fee when the spent fuel is shipped from the AFR for permanent disposal. Based on current spent fuel storage requirements, at least a 30 percent prepayment of the fee will be required

  19. Correlation between depression and burden observed in informal caregivers of people suffering from dementia with time spent on caregiving and dementia severity

    DEFF Research Database (Denmark)

    Gregersen, Rikke

    2016-01-01

    The aim of thestudy is to compare data on the examined populationof informal caregivers of people sufferingfrom dementia with previous studies, aswell as to assess the correlation between (i) depressiondetermined on the basis of the Centerfor Epidemiologic Studies Depression Scaleand (ii) caregiver...... dementia fromdifferent backgrounds were evaluated usingthe Zarit Caregiver Burden Scale and the Centerfor Epidemiologic Studies DepressionScale. Demographic data about the time devotedto caregiving and the number of hoursspend on caregiving weekly were gathered. Thetype of dementia and its stage were...... registeredusing the Global Deterioration Scale (GDS).With the aid of the Statistica StatSoft program,mutual correlations between the parameterswere measured. The study was conducted withinthe framework of AAL UnderstAID – a platformthat supports and helps to understandand assist caregivers in the care...

  20. Sorption of lead from aqueous solutions by spent tea leaf | Yoshita ...

    African Journals Online (AJOL)

    Pb) from solution. The Pb removal by the spent tea leaf adsorbent depended on pretreatment of spent tea leaf, adsorption contact time and adsorbent dosage. The optimum pretreatment conditions were confirmed to be that tea leaf was ground ...

  1. Health-Related Physical Fitness, BMI, physical activity and time spent at a computer screen in 6 and 7-year-old children from rural areas in Poland.

    Science.gov (United States)

    Cieśla, Elżbieta; Mleczko, Edward; Bergier, Józef; Markowska, Małgorzata; Nowak-Starz, Grażyna

    2014-01-01

    The objective of the study was determination of the effect of various forms of physical activity, BMI, and time devoted to computer games on the level of Health-Related Physical Fitness (H-RF) in 6-7-year-old children from Polish rural areas. The study covered 25,816 children aged 6-7: 12,693 girls and 13,123 boys. The evaluations included body height and weight, and 4 H-RF fitness components (trunk strength, explosive leg power, arm strength and flexibility). The BMI was calculated for each child. The Questionnaire directed to parents was designed to collect information concerning the time devoted by children to computer games, spontaneous and additional physical activity. The strength of the relationships between dependent and independent variables was determined using the Spearman's rank correlation (RSp), and the relationship by using the regression analysis. The BMI negatively affected the level of all the H-RF components analysed (p=0.000). The negative effect of computer games revealed itself only with respect to flexibility (p=0.000), explosive leg power (p=0.000) and trunk muscle strength (p=0.000). A positive effect of spontaneous activity was observed for flexibility (p=0.047), explosive leg power (p=0.000), and arm strength (p=0.000). Additional activity showed a positive relationship with trunk muscles strength (p=0.000), and explosive leg power (p=0.000). The results of studies suggest that it is necessary to pay attention to the prevention of diseases related with the risk of obesity and overweight among Polish rural children as early as at pre-school age. There is also a need during education for shaping in these children the awareness of concern about own body, and the need for active participation in various forms of physical activity.

  2. How Finnish and Swedish Learners’ Academic Self-Control Relates to Time Spent Online in Class, Perceptions of Educator Qualities, and School Appreciation: A Cross-Sectional Comparison

    Directory of Open Access Journals (Sweden)

    Thomas Arnesen

    2017-08-01

    Full Text Available In school settings, self-control is central to the ability of learners to complete their academic work successfully. Learners’ self-control is directly influenced by the ways in which educators execute their work, including their instructional explanations, their classroom management, and the expectations that they express to their learners. Our research on this phenomenon investigated Finnish and Swedish learners in upper secondary schools. Not only is the use of digital technology very different in these two countries; the autonomy and status of educators are as well. This article compares the empirical significance of antecedents of learners’ academic self-control in the two national settings by surveying 2191 learners in Swedish and Finnish schools. Our analysis applies structural equation modeling to two cross-sectional datasets, and the results reveal that the associations between educators’ instructional explanations, classroom management, and their high expectations on the one hand and learners’ academic self-control on the other are stronger overall among Finnish students than among Swedish students. Furthermore, the association between digital technology use and learners’ perceptions of conflict between school norms and Internet opportunities are much stronger in the Swedish sample than the Finnish sample. Lastly, we discuss the meaning of these results and their possible implications for research and practice.

  3. Spent fuel management in Japan

    International Nuclear Information System (INIS)

    Mineo, H.; Nomura, Y.; Sakamoto, K.

    1998-01-01

    In Japan 52 commercial nuclear power units are now operated, and the total power generation capacity is about 45 GWe. The cumulative amount of spent fuel arising is about 13,500 tU as of March 1997. Spent fuel is reprocessed, and recovered nuclear materials are to be recycled in LWRs and FBRs. In February 1997 short-term policy measures were announced by the Atomic Energy Commission, which addressed promotion of reprocessing programme in Rokkasho, plutonium utilization in LWRs, spent fuel management, backend measures and FBR development. With regard to the spent fuel management, the policy measures included expansion of spent fuel storage capacity at reactor sites and a study on spent fuel storage away from reactor sites, considering the increasing amount of spent fuel arising. Research and development on spent fuel storage has been carried out, particularly on dry storage technology. Fundamental studies are also conducted to implement the burnup credit into the criticality safety design of storage and transportation casks. Rokkasho reprocessing plant is being constructed towards its commencement in 2003, and Pu utilization in LWRs will be started in 1999. Research and development of future recycling technology are also continued for the establishment of nuclear fuel cycle based on FBRs and LWRs. (author)

  4. Malachite Green Adsorption by Spent Coffee Grounds

    Science.gov (United States)

    Syamimie Atirah Mat, Siti; Zati Hanani Syed Zuber, Sharifah; Rahim, Siti Kartini Enche Ab; Sohaimi, Khairunissa Syairah Ahmad; Halim, Noor Amirah Abdul; Fauziah Zainudin, Nor; Aida Yusoff, Nor; Munirah Rohaizad, Nor; Hidayah Ishak, Noor; Anuar, Adilah; Sarip, Mohd Sharizan Md

    2018-03-01

    In this work, the ability of spent coffee grounds (SCG) as a low-cost adsorbent to remove malachite green (MG) from aqueous solutions was studied. Batch adsorption tests were carried out to observe the effect of various experimental parameters such as contact time, initial concentration of malachite green and adsorbent dosage on the removal of dye. The results obtained show that the percentage of dye removal will decreased with the increased of initial concentration of dye in the range of 50 mg/L to 250 mg/L. Besides, percentage removal of dye was also found to be increased as the contact time increased until it reached equilibrium condition. The results also showed that the adsorbent dosage in range of 0.2 g to 1.0 g is proportional to the percentage removal of malachite green dye. Study on the kinetic adsorption and isotherm adsorption has also been investigated. The adsorption isotherm data were described by Langmuir isotherm with high-correlation coefficients while the experimental data showed the pseudo-second-order kinetics model was the best model for the adsorption of MG by SCG with the coefficients of correlation R2 > 0.9978.

  5. Containing method for spent fuel and spent fuel containing vessel

    International Nuclear Information System (INIS)

    Maekawa, Hiromichi; Hanada, Yoshine.

    1996-01-01

    Upon containing spent fuels, a metal vessel main body and a support spacer having fuel containing holes are provided. The support spacer is disposed in the inside of the metal vessel main body, and spent fuel assemblies are loaded in the fuel containing holes. Then, a lid is welded at the opening of the metal vessel main body to provide a sealing state. In this state, heat released from the spent fuel assemblies is transferred to the wall of the metal vessel main body via the support spacer. Since the support spacer has a greater heat conductivity than gases, heat of the spent fuel assemblies tends to be released to the outside, thereby capable of removing heat of the spent fuel assemblies effectively. In addition, since the surfaces of the spent fuel assemblies are in contact with the inner surface of the fuel containing holes of the support spacer, impact-resistance and earthquake-resistance are ensured, and radiation from the spent fuel assemblies is decayed by passing through the layer of the support spacer. (T.M.)

  6. WWER spent fuel storage

    Energy Technology Data Exchange (ETDEWEB)

    Bower, C C; Lettington, C [GEC Alsthom Engineering Systems Ltd., Whetstone (United Kingdom)

    1994-12-31

    Selection criteria for PAKS NPP dry storage system are outlined. They include the following: fuel temperature in storage; sub-criticality assurance (avoidance of criticality for fuel in the unirradiated condition without having to take credit for burn-up); assurance of decay heat removal; dose uptake to the operators and public; protection of environment; volume of waste produced during operation and decommissioning; physical protection of stored irradiated fuel assemblies; IAEA safeguards assurance; storage system versus final disposal route; cost of construction and extent of technology transfer to Hungarian industry. Several available systems are evaluated against these criteria, and as a result the GEC ALSTHOM Modular Vault Dry Store (MVDS) system has been selected. The MVDS is a passively cooled dry storage facility. Its most important technical, safety, licensing and technology transfer characteristics are outlined. On the basis of the experience gained some key questions and considerations related to the East European perspective in the field of spent fuel storage are discussed. 8 figs.

  7. WWER spent fuel storage

    International Nuclear Information System (INIS)

    Bower, C.C.; Lettington, C.

    1994-01-01

    Selection criteria for PAKS NPP dry storage system are outlined. They include the following: fuel temperature in storage; sub-criticality assurance (avoidance of criticality for fuel in the unirradiated condition without having to take credit for burn-up); assurance of decay heat removal; dose uptake to the operators and public; protection of environment; volume of waste produced during operation and decommissioning; physical protection of stored irradiated fuel assemblies; IAEA safeguards assurance; storage system versus final disposal route; cost of construction and extent of technology transfer to Hungarian industry. Several available systems are evaluated against these criteria, and as a result the GEC ALSTHOM Modular Vault Dry Store (MVDS) system has been selected. The MVDS is a passively cooled dry storage facility. Its most important technical, safety, licensing and technology transfer characteristics are outlined. On the basis of the experience gained some key questions and considerations related to the East European perspective in the field of spent fuel storage are discussed. 8 figs

  8. Spent fuel management overview: a global perspective

    International Nuclear Information System (INIS)

    Bonne, A.; Crijns, M.J.; Dyck, P.H.; Fukuda, K.; Mourogov, V.M.

    1999-01-01

    The paper defines the main spent fuel management strategies and options, highlights the challenges for spent fuel storage and gives an overview of the regional balances of spent fuel storage capacity and spent fuel arising. The relevant IAEA activities in the area of spent fuel management are summarised. (author)

  9. Development of spent fuel remote handling technology

    International Nuclear Information System (INIS)

    Yoon, J. S.; Hong, H. D.; Kim, Y. H.

    2001-03-01

    Since the amount of the spent fuel rapidly increases, the current R and D activities are focused on the technology development related with the storage and utilization of the spent fuel. In this research, to provide such a technology, the mechanical head-end process has been developed. In detail, the swing and shock-free crane and the RCGLUD(Remote Cask Grappling and Lid Unbolting Device) were developed for the safe transportation of the spent fuel assembly, the LLW drum and the transportation cask. Also, the disassembly devices required for the head-end process were developed. This process consists of an assembly downender, a rod extractor, a rod cutter, a fuel decladding device, a skeleton compactor, a force-rectifiable manipulator for the abnormal spent fuel disassembly, and the gantry type telescopic transporter, etc. To provide reliability and safety of these devices, the 3 dimensional graphic design system is developed. In this system, the mechanical devices are modelled and their operation is simulated in the virtual environment using the graphic simulation tools. So that the performance and the operational mal-function can be investigated prior to the fabrication of the devices. All the devices are tested and verified by using the fuel prototype at the mockup facility

  10. Software to improve spent fuel measurements using the FDET

    International Nuclear Information System (INIS)

    Staples, P.; Beddingfield, D.; Lestone, J.; Pelowitz, D.; Sprinkle, J.; Bytchkov, V.; Starovich, Z.; Harizanov, I.; Vellejo-Luna, J.; Lavender, C.

    2001-01-01

    Full text: Vast quantities of spent fuel are available for safeguard measurements, primarily in Commonwealth of Independent States (CIS) of the former Soviet Union. This spent fuel, much of which consists of long cooling time material, is going to become less unique in the world safeguards arena as reprocessing projects or permanent repositories continue to be delayed or postponed. The long cooling time of many of the spent fuel assemblies in the CIS countries being prepared for intermediate term storage promotes the possibility of increased accuracy in spent fuel assays. An important point to consider for the future that could advance safeguards measurements for re-verification and inspection measurements would be to determine what safeguards requirements should be imposed upon this 'new' class of spent fuel. Improvements in measurement capability will obviously affect the safeguards requirements. What most significantly enables this progress in spent fuel measurements is the improvement in computer processing power and software enhancements leading to user-friendly Graphical User Interfaces (GUI's). The software used for these projects significantly reduces the IAEA inspector's time both learning and operating computer and data acquisition systems. While at the same time by standardizing the spent fuel measurements it is possible to increase reproducibility and reliability of the measurement data. The inclusion of various analysis algorithms into the operating environment, which can be performed in real time upon the measurement data, can also lead to increases in safeguard reliability and improvements in efficiency to plant operations. (author)

  11. The psychosocial consequences of spent fuel disposal

    International Nuclear Information System (INIS)

    Paavola, J.; Eraenen, L.

    1999-03-01

    In this report the potential psychosocial consequences of spent fuel disposal to inhabitants of a community are assessed on the basis of earlier research. In studying the situation, different interpretations and meanings given to nuclear power are considered. First, spent fuel disposal is studied as fear-arousing and consequently stressful situation. Psychosomatic effects of stress and coping strategies used by an individual are presented. Stress as a collective phenomenon and coping mechanisms available for a community are also assessed. Stress reactions caused by natural disasters and technological disasters are compared. Consequences of nuclear power plant accidents are reviewed, e.g. research done on the accident at Three Mile Island power plant. Reasons for the disorganising effect on a community caused by a technological disaster are compared to the altruistic community often seen after natural disasters. The potential reactions that a spent fuel disposal plant can arouse in inhabitants are evaluated. Both short-term and long-term reactions are evaluated as well as reactions under normal functioning, after an incident and as a consequence of an accident. Finally an evaluation of how the decision-making system and citizens' opportunity to influence the decision-making affect the experience of threat is expressed. As a conclusion we see that spent fuel disposal can arouse fear and stress in people. However, the level of the stress is probably low. The stress is at strongest at the time of the starting of the spent fuel disposal plant. With time people get used to the presence of the plant and the threat experienced gets smaller. (orig.)

  12. Spent fuel treatment in Japan

    International Nuclear Information System (INIS)

    Takahashi, K.

    1999-01-01

    In Japan, 52 nuclear power reactors are operating with a total power generation capacity of 45 GWe. The cumulative amount of spent fuel arising, as of March 1998, is about 14,700 W. Spent fuel is reprocessed and recovered nuclear materials are to be recycled in LWRs and FBRs. Pu utilization in LWRs will commence in 1999. In January 1997, short-term policy measures were announced by the Atomic Energy Commission, which addressed promotion of the reprocessing programme in Rokkasho, plutonium utilization in LWRs, spent fuel management, back-end measures and FBR development. With regard to the spent fuel management, the policy measures included expansion of spent fuel storage capacity at reactor sites and a study on spent fuel storage away-from-reactor sites, considering the increasing amount of spent fuel arising. Valuable experience was been accumulated at the Tokai Reprocessing Plant (TRP), from the start of hot operation in 1977 up to now. The role of the TRP will be changed from an operation-oriented to a more R and D oriented facility, when PNC is reorganized into the new organization JNC. The Rokkasho reprocessing plant is under construction and is expected to commence operation in 2003. R and D of future recycling technologies is also continued for the establishment of a nuclear fuel cycle based on FBRs and LWRs. (author)

  13. Disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    1979-12-01

    This report addresses the topic of the mined geologic disposal of spent nuclear fuel from Pressurized Water Reactors (PWR) and Boiling Water Reactors (BWR). Although some fuel processing options are identified, most of the information in this report relates to the isolation of spent fuel in the form it is removed from the reactor. The characteristics of the waste management system and research which relate to spent fuel isolation are discussed. The differences between spent fuel and processed HLW which impact the waste isolation system are defined and evaluated for the nature and extent of that impact. What is known and what needs to be determined about spent fuel as a waste form to design a viable waste isolation system is presented. Other waste forms and programs such as geologic exploration, site characterization and licensing which are generic to all waste forms are also discussed. R and D is being carried out to establish the technical information to develop the methods used for disposal of spent fuel. All evidence to date indicates that there is no reason, based on safety considerations, that spent fuel should not be disposed of as a waste

  14. Dry spent fuel storage licensing

    International Nuclear Information System (INIS)

    Sturz, F.C.

    1995-01-01

    In the US, at-reactor-site dry spent fuel storage in independent spent fuel storage installations (ISFSI) has become the principal option for utilities needing storage capacity outside of the reactor spent fuel pools. Delays in the geologic repository operational date at or beyond 2010, and the increasing uncertainty of the US Department of Energy's (DOE) being able to site and license a Monitored Retrievable Storage (MRS) facility by 1998 make at-reactor-site dry storage of spent nuclear fuel increasingly desirable to utilities and DOE to meet the need for additional spent fuel storage capacity until disposal, in a repository, is available. The past year has been another busy year for dry spent fuel storage licensing. The licensing staff has been reviewing 7 applications and 12 amendment requests, as well as participating in inspection-related activities. The authors have licensed, on a site-specific basis, a variety of dry technologies (cask, module, and vault). By using certified designs, site-specific licensing is no longer required. Another new cask has been certified. They have received one new application for cask certification and two amendments to a certified cask design. As they stand on the brink of receiving multiple applications from DOE for the MPC, they are preparing to meet the needs of this national program. With the range of technical and licensing options available to utilities, the authors believe that utilities can meet their need for additional spent fuel storage capacity for essentially all reactor sites through the next decade

  15. Radionuclide release from research reactor spent fuel

    Energy Technology Data Exchange (ETDEWEB)

    Curtius, H., E-mail: h.curtius@fz-juelich.de [Forschungszentrum Juelich, Institut fuer Energieforschung, IEF-6 Sicherheitsforschung und Reaktortechnik, Geb. 05.3, D-52425 Juelich (Germany); Kaiser, G.; Mueller, E.; Bosbach, D. [Forschungszentrum Juelich, Institut fuer Energieforschung, IEF-6 Sicherheitsforschung und Reaktortechnik, Geb. 05.3, D-52425 Juelich (Germany)

    2011-09-01

    Numerous investigations with respect to LWR fuel under non oxidizing repository relevant conditions were performed. The results obtained indicate slow corrosion rates for the UO{sub 2} fuel matrix. Special fuel-types (mostly dispersed fuels, high enriched in {sup 235}U, cladded with aluminium) are used in German research reactors, whereas in German nuclear power plants, UO{sub 2}-fuel (LWR fuel, enrichment in {sup 235}U up to 5%, zircaloy as cladding) is used. Irradiated research reactor fuels contribute less than 1% to the total waste volume. In Germany, the state is responsible for fuel operation and for fuel back-end options. The institute for energy research (IEF-6) at the Research Center Juelich performs investigation with irradiated research reactor spent fuels under repository relevant conditions. In the study, the corrosion of research reactor spent fuel has been investigated in MgCl{sub 2}-rich salt brine and the radionuclide release fractions have been determined. Leaching experiments in brine with two different research reactor fuel-types were performed in a hot cell facility in order to determine the corrosion behaviour and the radionuclide release fractions. The corrosion of two dispersed research reactor fuel-types (UAl{sub x}-Al and U{sub 3}Si{sub 2}-Al) was studied in 400 mL MgCl{sub 2}-rich salt brine in the presence of Fe{sup 2+} under static and initially anoxic conditions. Within these experimental parameters, both fuel types corroded in the experimental time period of 3.5 years completely, and secondary alteration phases were formed. After complete corrosion of the used research reactor fuel samples, the inventories of Cs and Sr were quantitatively detected in solution. Solution concentrations of Am and Eu were lower than the solubility of Am(OH){sub 3}(s) and Eu(OH){sub 3}(s) solid phases respectively, and may be controlled by sorption processes. Pu concentrations may be controlled by Pu(IV) polymer species, but the presence of Pu(V) and Pu

  16. Case histories of West Valley spent fuel shipments: Final report

    Energy Technology Data Exchange (ETDEWEB)

    1987-01-01

    In 1983, NRC/FC initiated a study on institutional issues related to spent fuel shipments originating at the former spent fuel processing facility in West Valley, New York. FC staff viewed the shipment campaigns as a one-time opportunity to document the institutional issues that may arise with a substantial increase in spent fuel shipping activity. NRC subsequently contracted with the Aerospace Corporation for the West Valley Study. This report contains a detailed description of the events which took place prior to and during the spent fuel shipments. The report also contains a discussion of the shipment issues that arose, and presents general findings. Most of the institutional issues discussed in the report do not fall under NRC's transportation authority. The case histories provide a reference to agencies and other institutions that may be involved in future spent fuel shipping campaigns. 130 refs., 7 figs., 19 tabs.

  17. Case histories of West Valley spent fuel shipments: Final report

    International Nuclear Information System (INIS)

    1987-01-01

    In 1983, NRC/FC initiated a study on institutional issues related to spent fuel shipments originating at the former spent fuel processing facility in West Valley, New York. FC staff viewed the shipment campaigns as a one-time opportunity to document the institutional issues that may arise with a substantial increase in spent fuel shipping activity. NRC subsequently contracted with the Aerospace Corporation for the West Valley Study. This report contains a detailed description of the events which took place prior to and during the spent fuel shipments. The report also contains a discussion of the shipment issues that arose, and presents general findings. Most of the institutional issues discussed in the report do not fall under NRC's transportation authority. The case histories provide a reference to agencies and other institutions that may be involved in future spent fuel shipping campaigns. 130 refs., 7 figs., 19 tabs

  18. Assessment of spent fuel cooling

    International Nuclear Information System (INIS)

    Ibarra, J.G.; Jones, W.R.; Lanik, G.F.

    1997-01-01

    The paper presents the methodology, the findings, and the conclusions of a study that was done by the Nuclear Regulatory Commission's Office for Analysis and Evaluation of Operational Data (AEOD) on loss of spent fuel pool cooling. The study involved an examination of spent fuel pool designs, operating experience, operating practices, and procedures. AEOD's work was augmented in the area of statistics and probabilistic risk assessment by experts from the Idaho Nuclear Engineering Laboratory. Operating experience was integrated into a probabilistic risk assessment to gain insight on the risks from spent fuel pools

  19. Spent fuel disposal problem in Bulgaria

    Energy Technology Data Exchange (ETDEWEB)

    Milanov, M; Stefanova, I [Bylgarska Akademiya na Naukite, Sofia (Bulgaria). Inst. za Yadrena Izsledvaniya i Yadrena Energetika

    1994-12-31

    The internationally agreed basic safety principles and criteria for spent fuel (SF) and high level waste (HLW) disposal are outlined. In the framework of these principles the specific problems of Bulgaria described in the `National Concept for Radioactive Waste Management and Disposal in Republic of Bulgaria` are discussed. The possible alternatives for spent fuel management are: (1) sending the spent fuel for disposal in other country; (2) once-through cycle and (3) closed fuel cycle. A mixed solution of the problem is implemented in Bulgaria. According to the agreement between Bulgaria and former Soviet Union a part of the spent fuel has been returned to Russia. The once-through and closed-fuel cycle are also considered. The projected cumulated amount of spent fuel is estimated for two cases: (1) the six units of Kozloduy NPP are in operation till the end of their lifetime (3300 tHM) and (2) low estimate (2700 tHM) - only units 5 and 6 are operated till the end of their lifetime. The reprocessing of the total amount of 3300 tHM will lead to the production of about 370 m{sup 3} vitrified high level wastes. Together with the HLW about 1850 m{sup 3} cladding hulls and 7800 m{sup 3} intermediate-level wastes will be generated, which should be disposed off in deep geological repository. The total production of radioactive waste in once-through cycle is 181 000 m{sup 3}, and in closed cycle - 190 000 m{sup 3}. Geological investigations are performed resulting in categorization of the territory of the country based on geological, geotechnical and hydrogeological conditions. This will facilitate the choice of the most suitable location for deep geological repository. 7 figs., 11 refs.

  20. Management and disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    1987-05-01

    The programme consists of the long-term and short-term programme, the continued bedrock investigations, the underground research laboratory, the decision-making procedure in the site selection process and information questions during the site selection process. The National Board for Spent Nuclear Fuel hereby subunits both the SKB's R and D Programme 86 and the Board's statement concerning the programme. Decisions in the matter have been made by the Board's executive committee. (DG)

  1. Behavior of spent fuel and cask components after extended periods of dry storage

    International Nuclear Information System (INIS)

    Kenneally, R.; Kessler, J.

    2001-01-01

    The U.S. Nuclear Regulatory Commission (NRC) promulgated 10 CFR Part 72, Title 10, for the independent storage of spent nuclear fuel and high-level radioactive waste outside reactor spent fuel pools. Part 72 currently limits the license term for an independent spent fuel storage installation to 20 years from the date of issuance. Licenses may be renewed by the Commission at or before the expiration of the license term. Applications for renewal of a license should be filed at least two years prior to the expiration of the existing license. In preparation for possible license renewal, the NRC Office of Nuclear Material and Safeguards, Spent Fuel Project Office, is developing the technical basis for renewals of licenses and Certificates of Compliance for dry storage systems for spent nuclear fuel and high-level radioactive waste at independent spent fuel storage installation sites. An analysis of past performance of selected components of these systems is required as part of that technical basis. In the years 1980 through the early 1990, the Department of Energy (DOE) procured four prototype dry storage casks for testing at the Idaho National Engineering and Environmental Laboratory (INEEL): Castor-V/21, MC-10, TN-24P, and VSC-17. The primary purpose of the testing was to benchmark thermal and radiological codes and to determine the thermal and radiological characteristics of the casks. A series of examinations in 1999 and early 2000 to investigate the integrity of the Castor V/21 cask were undertaken. There is no evidence of significant degradation of the Castor V/21 cask systems important to safety from the time of initial loading of the cask in 1985 up to the time of testing in 1999. (author)

  2. Mercury Sorption onto Malt Spent Rootlets

    Science.gov (United States)

    Manariotis, I. D.; Anagnostopoulos, V.; Karapanagioti, H. K.; Chrysikopoulos, C.

    2011-12-01

    Mercury is a metal of particular concern due to its toxicity even at relatively low concentrations. The maximum permissible level for mercury in drinking water set by the European Union is 0.001 mg/L. Mercury is released into the environment via four principal pathways: (1) natural processes; i.e. a volcanic eruption, (2) incidental to some other activity; i.e. coal burning power plants, (3) accidentally during the manufacture, breakage or disposal of products that have mercury put into them deliberately, and (4) direct use in industrial settings. The present study focuses on the removal of mercury (II) from aqueous solutions via sorption onto Malt Spent Rootlets (MSR). Batch experiments were conducted employing MSR with size ranging from 0.18 to 1 mm. The effects of pH, mercury concentration, contact time, and solid to liquid ratio on mercury sorption onto MSR were investigated. The highest mercury removal from the aqueous phase, of 41%, was observed at pH of 5.

  3. Evaluation of the heat transfer in a geological repository concept containing PWR, VHTR and hybrid ads-fission spent fuels

    Energy Technology Data Exchange (ETDEWEB)

    Jonusan, Raoni A.S.; Pereira, Fernando; Velasquez, Carlos E.; Salome, Jean A.D.; Cardoso, Fabiano; Pereira, Claubia; Fortini, Angela, E-mail: claubia@nuclear.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

    2017-11-01

    The investigation of the thermal behavior of spent fuel (SF) materials is essential to determining appropriate potential sites to accommodate geological repositories as well as the design of canisters, considering their potential risk to people health and of environmental contamination. This work presents studies of the temperature in a canister containing spent fuels discharged from Pressurized Water Reactor (PWR), Very High-Temperature Reactor (VHTR) and Accelerator-Driven Subcritical Reactor System (ADS) reactor systems in a geological repository concept. The thermal analyses were performed with the software ANSYS, which is widely used to solve engineering problems through the Finite Element Method. The ANSYS Transient Thermal module was used. The spent nuclear fuels were set as heat sources using data of previous studies derived from decay heat curves. The studies were based on comparison of the mean temperature on a canister surface along the time under geological disposal conditions, for a same amount of each type of spent nuclear fuel evaluated. The results conclude that fuels from VHTR and ADS systems are inappropriate to be disposed in a standardized PWR canister, demanding new studies to determine the optimal amount of spent fuel and new internal canister geometries. It is also possible to conclude that the hypothetical situation of a single type of canister being used to accommodate different types of spent nuclear fuels is not technically feasible. (author)

  4. Spent fuel element storage facility

    International Nuclear Information System (INIS)

    Ukaji, Hideo; Yamashita, Rikuo.

    1981-01-01

    Purpose: To always keep water level of a spent fuel cask pit equal with water level of spent fuel storage pool by means of syphon principle. Constitution: The pool water of a spent fuel storage pool is airtightly communicated through a pipe with the pool water of a spent fuel cask, and a gate is provided between the pool and the cask. Since cask is conveyed into the cask pit as the gate close while conveying, the pool water level is raised an amount corresponding to the volume of the cask, and water flow through scattering pipe and the communication pipe to the storage pool. When the fuel is conveyed out of the cask, the water level is lowered in the amount corresponding to the volume in the cask pit, and the water in the pool flow through the communication pipe to the cask pit. (Sekiya, K.)

  5. Spent fuel management in Spain

    International Nuclear Information System (INIS)

    Gonzalez, J.L.

    2002-01-01

    The spent fuel management strategy in Spain is presented. The strategy includes temporary solutions and plans for final disposal. The need for R and D including partitioning and transmutation, as well as the financial constraints are also addressed. (author)

  6. Spent fuel management in Canada

    International Nuclear Information System (INIS)

    Khan, A.; Pattantyus, P.

    1999-01-01

    The current status of the Canadian spent fuel storage is presented. This includes wet and dry interim storage. Extension of wet interim storage facilities is nor planned, as dry technologies have found wide acceptance. The Canadian nuclear program is sustained by commercial Ontario Hydro CANDU type reactors, since 1971, representing 13600 MW(e) of installed capacity, able to produce 9200 spent fuel bundles (1800 tU) every year, and Hydro Quebec and New Brunswick CANDU reactors each producing 685 MW(e) and about 100 tU of spent fuel annually. The implementation of various interim (wt and dry) storage technologies resulted in simple, dense and low cost systems. Economical factors determined that the open cycle option be adopted for the CANDU type reactors rather that recycling the spent fuel. Research and development activities for immobilization and final disposal of nuclear waste are being undertaken in the Canadian Nuclear Fuel Waste Management Program

  7. Transportation of spent MTR fuels

    International Nuclear Information System (INIS)

    Raisonnier, D.

    1997-01-01

    This paper gives an overview of the various aspects of MTR spent fuel transportation and provides in particular information about the on-going shipment of 4 spent fuel casks to the United States. Transnucleaire is a transport and Engineering Company created in 1963 at the request of the French Atomic Energy Commission. The company followed the growth of the world nuclear industry and has now six subsidiaries and affiliated companies established in countries with major nuclear programs

  8. Transportation of spent MTR fuels

    Energy Technology Data Exchange (ETDEWEB)

    Raisonnier, D.

    1997-08-01

    This paper gives an overview of the various aspects of MTR spent fuel transportation and provides in particular information about the on-going shipment of 4 spent fuel casks to the United States. Transnucleaire is a transport and Engineering Company created in 1963 at the request of the French Atomic Energy Commission. The company followed the growth of the world nuclear industry and has now six subsidiaries and affiliated companies established in countries with major nuclear programs.

  9. Spent-fuel-storage alternatives

    International Nuclear Information System (INIS)

    1980-01-01

    The Spent Fuel Storage Alternatives meeting was a technical forum in which 37 experts from 12 states discussed storage alternatives that are available or are under development. The subject matter was divided into the following five areas: techniques for increasing fuel storage density; dry storage of spent fuel; fuel characterization and conditioning; fuel storage operating experience; and storage and transport economics. Nineteen of the 21 papers which were presented at this meeting are included in this Proceedings. These have been abstracted and indexed

  10. Spent fuel management in India

    International Nuclear Information System (INIS)

    Balu, K.

    1998-01-01

    From Indian point of view, the spent fuel management by the reprocessing and plutonium recycle option is considered to be a superior and an inevitable option. The nuclear energy programme in Indian envisages three stages of implementation involving installation of thermal reactors in the first phase followed by recycling of plutonium from reprocessed fuel in fast breeder reactors and in the third phase utilization of its large thorium reserves in reactor system based on U-233-Th cycle. The Indian programme for Waste Management envisages disposal of low and intermediate level radioactive waste in near surface disposal facilities and deep geological disposal for high level and alpha bearing wastes. A Waste Immobilization Plant (WHIP), employing metallic melter for HLW vitrification is operational at Tarapur. Two more WIPs are being set up at Kalpakkam and Tarapur. A Solid waste Storage Surveillance Facility (SSSF) is also set up for interim storage of vitrified HLW. Site investigations are in progress for selecting site for ultimate disposal in igneous rock formations. R and D works is taken up on partitioning of HLW. Solvent extraction and extraction chromatographic studies are in progress. Presently emphasis is on separation of heat generating short lived nuclides like strontium and alpha emitters. (author)

  11. Investigation of Stress-Strain-Time Relationships of Concrete Filled Steel Tube Columns

    Directory of Open Access Journals (Sweden)

    Mutlu Seçer

    2010-01-01

    Full Text Available In this study, time dependent creep and shrinkage behaviors of concrete filled steel box section columns are investigated by using various methods. Time dependent behavior is examined by using effective modulus method, age-adjusted effective modulus method, creep rate method and Dischinger method. Shrinkage and creep strains are modeled using ACI 209 specification. In the study, in order to investigate time dependent behavior numerically, a concrete filled steel box section column is selected in a twenty story building and the time dependent stress decrease in concrete and stress increase in steel box section and the changes in strain components are calculated. Stress – time, strain – time and strain components – time graphics are shown and the advantages and the disadvantages of the numerical methods in modeling the time dependent behavior are revealed respectively.

  12. Survey of experience with dry storage of spent nuclear fuel and update of wet storage experience

    International Nuclear Information System (INIS)

    1988-01-01

    Spent fuel storage is an important part of spent fuel management. At present about 45,000 t of spent water reactor fuel have been discharged worldwide. Only a small fraction of this fuel (approximately 7%) has been reprocessed. The amount of spent fuel arisings will increase significantly in the next 15 years. Estimates indicate that up to the year 2000 about 200,000 t HM of spent fuel could be accumulated. In view of the large quantities of spent fuel discharged from nuclear power plants and future expected discharges, many countries are involved in the construction of facilities for the storage of spent fuel and in the development of effective methods for spent fuel surveillance and monitoring to ensure that reliable and safe operation of storage facilities is achievable until the time when the final disposal of spent fuel or high level wastes is feasible. The first demonstrations of final disposal are not expected before the years 2000-2020. This is why the long term storage of spent fuel and HLW is a vital problem for all countries with nuclear power programmes. The present survey contains data on dry storage and recent information on wet storage, transportation, rod consolidation, etc. The main aim is to provide spent fuel management policy making organizations, designers, scientists and spent fuel storage facility operators with the latest information on spent fuel storage technology under dry and wet conditions and on innovations in this field. Refs, figs and tabs

  13. Investigating the role of time in affective forecasting: temporal influences on forecasting accuracy.

    NARCIS (Netherlands)

    Finkenauer, C.; Gallucci, M.; van Dijk, W.; Pollmann, M.M.H.

    2007-01-01

    Using extensive diary data from people taking their driver's license exam, the authors investigated the role of time in affective forecasting accuracy. Replicating existing findings, participants grossly overestimated the intensity and duration of their negative affect after failure and only

  14. Comparison of spent fuel management fee collection alternatives

    International Nuclear Information System (INIS)

    White, M.K.; Engel, R.L.

    1979-01-01

    Five alternative methods for recovering the costs of spent fuel management were evaluated. These alternatives consist of collecting the fee for various components of spent fuel management cost (AFR basin storage, transportation from AFR basin to the repository, packaging, repository, R and D, and government overhead) at times ranging from generation of power to delivery of the spent fuel to the government. The five fee collection mechanisms were analyzed to determine how well they serve the interests of the public and the electricity ratepayer

  15. Recovery of molybdenum and cobalt powders from spent hydrogenation catalyst

    International Nuclear Information System (INIS)

    Rabah, M.A.; Hewaidy, I.F.; Farghaly, F.E.

    1996-01-01

    Free powders as well as compact shapes of molybdenum and cobalt have been successfully recovered from spent hydrogenation and desulphurization catalysts. A process flow sheet was followed involving crushing, milling, particle sizing, hydrometallurgical acid leaching roasting of the obtained salts in an atmospheric oxygen to obtain the respective oxides. These were reduced by hydrogen gas at 110 degree C and 900 degree C respectively. Parameters affecting the properties of the products and the recovery efficiency value such as acid concentration, particle diameter of the solid catalyst, temperature time under a constant mass flow rate the hydrogen gas, have been investigated. A mixture of concentration.sulphuric and nitric acids (3:1 by volume) achieved adequate recovery of both metals. The latter increased with the increase in acid concentration, time up 10 3 hours and temperature: 100 degree C and with the decrease in particle diameter of the spent catalyst. The PH of the obtained filtrate was adjusted to 2 with ammonia to precipitate insoluble ammonium molybdate and a solution of cobalt sulphate. Cobalt hydroxide can be precipitate from the latter solution at a PH = 7.6 using excess ammonium hydroxide solution. The obtained results showed that the metallic products are technically pure meeting the standard specifications. Compact shapes of molybdenum acquire density values increasing with the increase of the pressing load whereby a maximum density value of 2280 kg/m 3 is attained at 0.75 MPa. Maximum recovery efficiency amounts to 96%. 10 figs., 3 tabs

  16. NDA measurements on spent fuel assemblies at Tihange 1 by means of the ION 1/FORK

    International Nuclear Information System (INIS)

    Carchon, R.; Smaers, G.; Verrecchia, G.P.D.; Arlt, R.; Stoyanova, I.; Satinet, J.

    1986-06-01

    This report describes field tests performed at Tihange 1 Nuclear Power Station on PWR spent fuel by means of the ION 1-FORK detector. Two detector systems and three electronics systems were used to investigate the same fuel assemblies with various burn-ups and cooling times. The purpose of the exercise was to test the performance of the instrument for as well inspection purposes as for fuel management. The results are presented and discussed. (Author)

  17. Spent-fuel transport: available as needed

    International Nuclear Information System (INIS)

    Macklin, L.

    1976-01-01

    As a result of the general uncertainty as to when commercial reprocessing will actually take place in the United States (U.S.) and the long lead times now required before bringing a spent-fuel cask system in operation, it appears that serious problems can arise by 1979-1980 in cask capacity availability. Compounding the uncertainty with respect to cask capacity availability is the position taken by some of the U.S. railroad systems and some state and local governmental agencies in imposing restraints in the movement of spent fuel. By utility companies taking risk in committing to casks in advance of the actual requirement dates and by cask suppliers assuming the risks of licensing, costs, and delivery schedules, this potential bottleneck could be minimized

  18. Impact analysis of spent fuel jacket assemblies

    International Nuclear Information System (INIS)

    Aramayo, G.A.

    1994-01-01

    As part of the analyses performed in support of the reracking of the High Flux Isotope Reactor pool, it became necessary to prove the structural integrity of the spent fuel jacket assemblies subjected to gravity drop that result from postulated accidents associated with the handling of these assemblies while submerged in the pool. The spent fuel jacket assemblies are an integral part of the reracking project, and serve to house fuel assemblies. The structure integrity of the jacket assemblies from loads that result from impact from a height of 10 feet onto specified targets has been performed analytically using the computer program LS-DYNA3D. Nine attitudes of the assembly at the time of impact have been considered. Results of the analyses show that there is no failure of the assemblies as a result of the impact scenarios considered

  19. Development of a reference spent fuel library of 17x17 PWR fuel assemblies

    International Nuclear Information System (INIS)

    Rossa, Riccardo; Borella, Alessandro; Van der Meer, Klaas

    2013-01-01

    One of the most common ways to investigate new Non-Destructive Assays (NDA) for the spent fuel assemblies are Monte Carlo simulations. In order to build realistic models the user must define in an accurate way the material compositions and the source terms in the system. This information can be obtained using burnup codes such as ORIGEN-ARP and ALEPH2.2, developed at SCK-CEN. These software applications allow the user to select the irradiation history of the fuel assembly and to calculate the corresponding isotopic composition and neutron/gamma emissions as a function of time. In the framework of the development of an innovative NDA for spent fuel verifications, SCK•CEN built an extensive fuel library for 17x17 PWR assemblies, using both ORIGEN-ARP and ALEPH2.2. The parameters considered in the calculations were initial enrichment, discharge burnup, and cooling time. The combination of these variables allows to obtain more than 1500 test cases. Considering the broad range of the parameters, the fuel library can be used for other purposes apart from spent fuel verifications, for instance for the direct disposal in geological repositories. In addition to the isotopic composition of the spent fuel, the neutron and photon emissions were also calculated and compared between the two codes. The comparison of the isotopic composition showed a good agreement between the codes for most of the relevant isotopes in the spent fuel. However, specific isotopes as well as neutron and gamma spectra still need to be investigated in detail.

  20. Spent Nuclear Fuel project, project management plan

    International Nuclear Information System (INIS)

    Fuquay, B.J.

    1995-01-01

    The Hanford Spent Nuclear Fuel Project has been established to safely store spent nuclear fuel at the Hanford Site. This Project Management Plan sets forth the management basis for the Spent Nuclear Fuel Project. The plan applies to all fabrication and construction projects, operation of the Spent Nuclear Fuel Project facilities, and necessary engineering and management functions within the scope of the project

  1. Investigation of the Adaptability of Transient Stability Assessment Methods to Real-Time Operation

    DEFF Research Database (Denmark)

    Weckesser, Johannes Tilman Gabriel; Jóhannsson, Hjörtur; Sommer, Stefan

    2012-01-01

    In this paper, an investigation of the adaptability of available transient stability assessment methods to real-time operation and their real-time performance is carried out. Two approaches based on Lyapunov’s method and the equal area criterion are analyzed. The results allow to determine...

  2. What Influences Chinese Undergraduates' Time Management in Online Groupwork? An Empirical Investigation

    Science.gov (United States)

    Xu, Jianzhong; Du, Jianxia; Fan, Xitao

    2017-01-01

    The present investigation examines models of factors influencing time management in online groupwork for Chinese undergraduates. Multilevel findings showed that time management was positively related to five individual-level variables, including online courses taken previously, learning-oriented reasons, arranging the environment, help-seeking and…

  3. Container for spent fuel assembly

    International Nuclear Information System (INIS)

    Sawai, Takeshi.

    1996-01-01

    The container of the present invention comprises a container main body having a body portion which can contain spent fuel assemblies and a lid, and heat pipes having an evaporation portion disposed along the outer surface of the spent fuel assemblies to be contained and a condensation portion exposed to the outside of the container main body. Further, the heat pipe is formed spirally at the evaporation portions so as to surround the outer circumference of the spent fuel assemblies, branched into a plurality of portions at the condensation portion, each of the branched portion of the condensation portion being exposed to the outside of the container main body, and is tightly in contact with the periphery of the slit portions disposed to the container main body. Then, since released after heat is transferred to the outside of the container main body from the evaporation portion of the heat pipe along the outer surface of the spent fuel assemblies by way of the condensation portion of the heat pipes exposed to the outside of the container main body, the efficiency of the heat transfer is extremely improved to enhance the effect of removing heat of spent fuel assemblies. Further, cooling effect is enhanced by the spiral form of the evaporation portion and the branched condensation portion. (N.H.)

  4. Further Evaluation of the Neutron Resonance Transmission Analysis (NRTA) Technique for Assaying Plutonium in Spent Fuel

    Energy Technology Data Exchange (ETDEWEB)

    J. W. Sterbentz; D. L. Chichester

    2011-09-01

    This is an end-of-year report (Fiscal Year (FY) 2011) for the second year of effort on a project funded by the National Nuclear Security Administration's Office of Nuclear Safeguards (NA-241). The goal of this project is to investigate the feasibility of using Neutron Resonance Transmission Analysis (NRTA) to assay plutonium in commercial light-water-reactor spent fuel. This project is part of a larger research effort within the Next-Generation Safeguards Initiative (NGSI) to evaluate methods for assaying plutonium in spent fuel, the Plutonium Assay Challenge. The second-year goals for this project included: (1) assessing the neutron source strength needed for the NRTA technique, (2) estimating count times, (3) assessing the effect of temperature on the transmitted signal, (4) estimating plutonium content in a spent fuel assembly, (5) providing a preliminary assessment of the neutron detectors, and (6) documenting this work in an end of the year report (this report). Research teams at Los Alamos National Laboratory (LANL), Lawrence Berkeley National Laboratory (LBNL), Pacific Northwest National Laboratory (PNNL), and at several universities are also working to investigate plutonium assay methods for spent-fuel safeguards. While the NRTA technique is well proven in the scientific literature for assaying individual spent fuel pins, it is a newcomer to the current NGSI efforts studying Pu assay method techniques having just started in March 2010; several analytical techniques have been under investigation within this program for two to three years or more. This report summarizes work performed over a nine month period from January-September 2011 and is to be considered a follow-on or add-on report to our previous published summary report from December 2010 (INL/EXT-10-20620).

  5. Reduction of uranium in disposal conditions of spent nuclear fuel

    International Nuclear Information System (INIS)

    Myllykylae, E.

    2008-02-01

    This literature study is a summary of publications, in which the reduction of uranium by iron has been investigated in anaerobic groundwater conditions or in aqueous solution in general. The basics of the reduction phenomena and the oxidation states, complexes and solubilities of uranium and iron in groundwaters are discussed as an introduction to the subject, as well as, the Finnish disposal concept of spent nuclear fuel. The spent fuel itself mainly (∼96 %) consists of a sparingly soluble uranium(IV) dioxide, UO 2 (s), which is stable phase in the anticipated reducing disposal conditions. If spent fuel gets in contact with groundwater, oxidizing conditions might be induced by the radiolysis of water, or by the intrusion of oxidizing glacial melting water. Under these conditions, the oxidation and dissolution of uranium dioxide to more soluble U(VI) species could occur. This could lead to the mobilization of uranium and other components of spent fuel matrix including fission products and transuranium elements. The reduction of uranium back to oxidation state U(IV) can be considered as a favourable immobilization mechanism in a long-term, leading to precipitation due to the low solubility of U(IV) species. The cast iron insert of the disposal canister and its anaerobic corrosion products are the most important reductants under disposal conditions, but dissolved ferrous iron may also function as reductant. Other iron sources in the buffer or near-field rock, are also considered as possible reductants. The reduction of uranium is a very challenging phenomenon to investigate. The experimental studies need e.g. well-controlled anoxic conditions and measurements of oxidation states. Reduction and other simultaneous phenomena are difficult to distinghuish. The groundwater conditions (pH, Eh and ions) influence on the prevailing complexes of U and Fe and on forming corrosion products of iron and, thus they determine also the redox chemistry. The partial reduction of

  6. The cascad spent fuel dry storage facility

    International Nuclear Information System (INIS)

    Guay, P.; Bonnet, C.

    1991-01-01

    France has a wide variety of experimental spent fuels different from LWR spent fuel discharged from commercial reactors. Reprocessing such fuels would thus require the development and construction of special facilities. The French Atomic Energy Commission (CEA) has consequently opted for long-term interim storage of these spent fuels over a period of 50 years. Comparative studies of different storage concepts have been conducted on the basis of safety (mainly containment barriers and cooling), economic, modular design and operating flexibility criteria. These studies have shown that dry storage in a concrete vault cooled by natural convection is the best solution. A research and development program including theoretical investigations and mock-up tests confirmed the feasibility of cooling by natural convection and the validity of design rules applied for fuel storage. A facility called CASCAD was built at the CEA's Cadarache Nuclear Research Center, where it has been operational since mid-1990. This paper describes the CASCAD facility and indicates how its concept can be applied to storage of LWR fuel assemblies

  7. Immobilisation Of Spent Ion Exchange Resins Using Portland Cement Blending With Organic Material

    International Nuclear Information System (INIS)

    Zalina Laili; Mohd Abdul Wahab; Nur Azna Mahmud

    2014-01-01

    Immobilisation of spent ion exchange resins (spent resins) using Portland cement blending with organic material for example bio char was investigated. The performance of cement-bio char matrix for immobilisation of spent ion exchange resins was evaluated based on their compression strength and leachability under different experimental conditions. The results showed that the amount of bio char and spent resins loading effect the compressive strength of the waste form. Several factors affecting the leaching behaviour of immobilised spent resins in cement-bio char matrix. (author)

  8. Development of spent fuel remote handling technology

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Ji Sup; Park, B S; Park, Y S; Oh, S C; Kim, S H; Cho, M W; Hong, D H

    1997-12-01

    Since the nation`s policy on spent fuel management is not finalized, the technical items commonly required for safe management and recycling of spent fuel - remote technologies of transportation, inspection, maintenance, and disassembly of spent fuel - are selected and pursued. In this regards, the following R and D activities are carried out : collision free transportation of spent fuel assembly, mechanical disassembly of spent nuclear fuel and graphical simulation of fuel handling / disassembly process. (author). 36 refs., 16 tabs., 77 figs

  9. Development of spent fuel remote handling technology

    International Nuclear Information System (INIS)

    Yoon, Ji Sup; Park, B. S.; Park, Y. S.; Oh, S. C.; Kim, S. H.; Cho, M. W.; Hong, D. H.

    1997-12-01

    Since the nation's policy on spent fuel management is not finalized, the technical items commonly required for safe management and recycling of spent fuel - remote technologies of transportation, inspection, maintenance, and disassembly of spent fuel - are selected and pursued. In this regards, the following R and D activities are carried out : collision free transportation of spent fuel assembly, mechanical disassembly of spent nuclear fuel and graphical simulation of fuel handling / disassembly process. (author). 36 refs., 16 tabs., 77 figs

  10. Spent Pot Lining Characterization Framework

    Science.gov (United States)

    Ospina, Gustavo; Hassan, Mohamed I.

    2017-09-01

    Spent pot lining (SPL) management represents a major concern for aluminum smelters. There are two key elements for spent pot lining management: recycling and safe storage. Spent pot lining waste can potentially have beneficial uses in co-firing in cement plants. Also, safe storage of SPL is of utmost importance. Gas generation of SPL reaction with water and ignition sensitivity must be studied. However, determining the feasibility of SPL co-firing and developing the required procedures for safe storage rely on determining experimentally all the necessary SPL properties along with the appropriate test methods, recognized by emissions standards and fire safety design codes. The applicable regulations and relevant SPL properties for this purpose are presented along with the corresponding test methods.

  11. Spent fuel storage requirements, 1988

    International Nuclear Information System (INIS)

    1988-10-01

    Historical inventories of spent fuel and Department of Energy (DOE) estimates of future discharges from US commercial nuclear reactors are presented for the next 20 years, through the year 2007. The eventual needs for additional spent fuel storage capacity are estimated. These estimates are based on the maximum capacities within current and planned at-reactor facilities and on any planned transshipments of fuel to other reactors or facilities. Historical data through December 1987 and projected discharges through the end of reactor life are used in this analysis. The source data was supplied by the utilities to DOE through the 1988 RW-859 data survey and by DOE estimates of future nuclear capacity, generation, and spent fuel discharges. 12 refs., 3 figs., 28 tabs

  12. SO{sub 2} Retention by CaO-Based Sorbent Spent in CO{sub 2} Looping Cycles

    Energy Technology Data Exchange (ETDEWEB)

    Manovic, V.; Anthony, E.J.; Loncarevic, D.

    2009-07-15

    CaO-based looping cycles are promising processes for CO{sub 2} Capture from both syngas and flue gas. The technology is based on cyclical carbonation of CaO and regeneration of CaCO{sub 3} in a dual fluidized-bed reactor to produce a pure CO{sub 2} stream suitable for sequestration. Use of spent sorbent from CO{sub 2} looping cycles for SO{sub 2} capture is investigated. Three limestones were investigated: Kelly Rock (Canada), La Blanca (Spain), and Katowice (Poland, Upper Silesia). Carbonation/calcination cycles were performed in a tube furnace with both the original limestones and samples thermally pretreated for different times (i.e., sintered). The spent sorbent samples were sulfated in a thermogravimetric analyzer (TGA). The changes in the resulting sorbent pore structure were then investigated using mercury porosimetry. It has been shown that the sulfation rates of both thermally pretreated and spent sorbent samples are lower in comparison with those of the original samples. However, final conversions of both spent and pretreated sorbents after longer sulfation time were comparable or higher than those observed for the original sorbents under comparable conditions. Maximum sulfation levels strongly depend on sorbent porosity and pore surface area. The results showed that spent sorbent samples from CO{sub 2} looping cycles can be used as sorbents for SO{sub 2} retention in cases where significant porosity loss does not occur during CO{sub 2} reaction cycles. In the case of spent Kelly Rock and Katowice samples, sorbent particles are practically uniformly sulfated, achieving final conversions that are determined by the total pore volume available for the bulky CaSO{sub 4} product.

  13. Economics of National Waste Terminal Storage Spent Fuel Pricing Study

    International Nuclear Information System (INIS)

    1978-05-01

    The methodology for equitably pricing commercial nuclear spent fuel management is developed, and the results of four sample calculations are presented. The spent fuel management program analyzed places encapsulated spent fuel in bedded salt while maintaining long-term retrievability. System design was reasonable but not optimum. When required, privately-owned Away From Reactor (AFR) storage is provided and the spent fuel placed in AFR storage is eventually transported to final storage. Applicable Research and Development and Government Overhead are included. The cost of each component by year was estimated from the most recent applicable data source available. These costs were input to the pricing methodology to establish a one-time charge whose present value exactly recovered the present value of the expenditure flow. The four cases exercised were combinations of a high and a low quantity of spent fuel managed, with a single repository (venture) or a multiple repository (campaign) approach to system financial structure. The price for spent fuel management calculated ranged from 116 to 152 dollars (1978) per kilogram charged initially to the reactor. The effect of spent fuel receiving rate on price is illustrated by the fact that the extremes of price did not coincide with the cases having the extremes of undiscounted cost. These prices for spent fuel management are comparable in magnitude to other fuel cycle costs. The range of variation is small because of compensating effects, i.e., additional costs for high early deliveries (AFR and transportation) versus lower present value of future revenue for later delivery cases. The methodology contains numerous conservative assumptions, provisions for contingencies, and covers the complete set of spent fuel management expenses

  14. Spent fuel management in Spain

    International Nuclear Information System (INIS)

    Gago, J.A.; Gravalos, J.M.

    1996-01-01

    There are presently nine Light Water Reactors in operation, representing around a 34% of the overall electricity production. In the early years, a small amount of spent fuel was sent to be reprocessed, although this policy was cancelled in favor of the open cycle option. A state owned company, ENRESA, was created in 1984, which was given the mandate to manage all kinds of radioactive wastes generated in the country. Under the present scenario, a rough overall amount of 7000 tU of spent fuel will be produced during the lifetime of the plants, which will go into final disposal. (author)

  15. Spent-fuel-storage alternatives

    Energy Technology Data Exchange (ETDEWEB)

    1980-01-01

    The Spent Fuel Storage Alternatives meeting was a technical forum in which 37 experts from 12 states discussed storage alternatives that are available or are under development. The subject matter was divided into the following five areas: techniques for increasing fuel storage density; dry storage of spent fuel; fuel characterization and conditioning; fuel storage operating experience; and storage and transport economics. Nineteen of the 21 papers which were presented at this meeting are included in this Proceedings. These have been abstracted and indexed. (ATT)

  16. Transport device of spent fuel

    International Nuclear Information System (INIS)

    Watanabe, Takashi.

    1976-01-01

    Object: To provide a transport device of spent fuel particularly used in a fast breeder, which can enhance accessibility to travelling mechanism portions and exchangeability thereof to facilitate maintenance in the event of failure. Structure: On a travelling floor, which has a function to shield radioactive rays, extending in a direction of transporting spent fuel and being formed with a break passing through in a direction wall thickness, a travelling body is moved along the break. The travelling body has a support rod member mounted thereon, and the support rod member is moved within the break, the support rod member having a fuel support pocket suspended therefrom. (Furukawa, Y.)

  17. Recovery of decommissioning and spent fuel charges

    International Nuclear Information System (INIS)

    Bermanis, G.

    1982-01-01

    The licensing and financial aspects of NPP decommissioning, deactivation and dismantling of radioactive equipment in the USA are considered. Data on the costs of spent fuel transport and conservation are given. The state of the problem development in other countries is briefly described. It is pointed out that the technical aspect of the problem is much better studied than that of license-financial problem. At the same time in contrast to TPP NPP use is connected with considerable expenses after the end of a power plant sevice time

  18. Research and development for decontamination system of spent resin in Hanbit Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Gi Hong [Dept. of Nuclear Engineering, Chosun University, Gwangju (Korea, Republic of)

    2015-12-15

    When reactor coolant leaks occur due to cracks of a steam generator tube, radioactive materials contained in the primary cooling water in nuclear power plant are forced out toward the secondary systems. At this time the secondary water purification resin in the ion exchange resin tower of the steam generator blowdown system is contaminated by the radioactivity of the leaked radioactive materials, so we pack this in special containers and store temporarily because we could not dispose it by ourselves. If steam generator tube leakage occurs, it produces contaminated spent resins annually about 5,000-7,000 liters. This may increase the amount of nuclear waste productions, a disposal working cost and a unit price of generating electricity in the plant. For this reasons, it is required to develop a decontamination process technique for reducing the radioactive level of these resins enough to handle by the self-disposal method. In this research, First, Investigated the structure and properties of the ion exchange resin used in a steam generator blowdown system. Second, Checked for a occurrence status of contaminated spent resin and a disposal technology. Third, identified the chemical characteristics of the waste radionuclides of the spent resin, and examined ionic bonding and separation mechanism of radioactive nuclear species and a spent resin. Finally, we carried out the decontamination experiment using chemicals, ultrasound, microbubbles, supercritical carbon dioxide to process these spent resin. In the case of the spent resin decontamination method using chemicals, the higher the concentration of the drug decontamination efficiency was higher. In the ultrasound method, foreign matter of the spent resin was removed and was found that the level of radioactivity is below of the MDA. In the microbubbles method, we found that the concentration of the radioactivity decreased after the experiment, so it can be used to the decontamination process of the spent resin. In

  19. Research and development for decontamination system of spent resin in Hanbit Nuclear Power Plant

    International Nuclear Information System (INIS)

    Sung, Gi Hong

    2015-01-01

    When reactor coolant leaks occur due to cracks of a steam generator tube, radioactive materials contained in the primary cooling water in nuclear power plant are forced out toward the secondary systems. At this time the secondary water purification resin in the ion exchange resin tower of the steam generator blowdown system is contaminated by the radioactivity of the leaked radioactive materials, so we pack this in special containers and store temporarily because we could not dispose it by ourselves. If steam generator tube leakage occurs, it produces contaminated spent resins annually about 5,000-7,000 liters. This may increase the amount of nuclear waste productions, a disposal working cost and a unit price of generating electricity in the plant. For this reasons, it is required to develop a decontamination process technique for reducing the radioactive level of these resins enough to handle by the self-disposal method. In this research, First, Investigated the structure and properties of the ion exchange resin used in a steam generator blowdown system. Second, Checked for a occurrence status of contaminated spent resin and a disposal technology. Third, identified the chemical characteristics of the waste radionuclides of the spent resin, and examined ionic bonding and separation mechanism of radioactive nuclear species and a spent resin. Finally, we carried out the decontamination experiment using chemicals, ultrasound, microbubbles, supercritical carbon dioxide to process these spent resin. In the case of the spent resin decontamination method using chemicals, the higher the concentration of the drug decontamination efficiency was higher. In the ultrasound method, foreign matter of the spent resin was removed and was found that the level of radioactivity is below of the MDA. In the microbubbles method, we found that the concentration of the radioactivity decreased after the experiment, so it can be used to the decontamination process of the spent resin. In

  20. Development of spent fuel remote handling technology

    Energy Technology Data Exchange (ETDEWEB)

    Park, B. S.; Yoon, J. S.; Hong, H. D. (and others)

    2007-02-15

    In this research, the remote handling technology was developed for the ACP application. The ACP gives a possible solution to reduce the rapidly cumulative amount of spent fuels generated from the nuclear power plants in Korea. The remote technologies developed in this work are a slitting device, a voloxidizer, a modified telescopic servo manipulator and a digital mock-up. A slitting device was developed to declad the spent fuel rod-cuts and collect the spent fuel UO{sub 2} pellets. A voloxidizer was developed to convert the spent fuel UO{sub 2} pellets obtained from the slitting process in to U{sub 3}O{sub 8} powder. Experiments were performed to test the capabilities and remote operation of the developed slitting device and voloxidizer by using simulated rod-cuts and fuel in the ACP hot cell. A telescopic servo manipulator was redesigned and manufactured improving the structure of the prototype. This servo manipulator was installed in the ACP hot cell, and the target module for maintenance of the process equipment was selected. The optimal procedures for remote operation were made through the maintenance tests by using the servo manipulator. The ACP digital mockup in a virtual environment was established to secure a reliability and safety of remote operation and maintenance. The simulation for the remote operation and maintenance was implemented and the operability was analyzed. A digital mockup about the preliminary conceptual design of an enginnering-scale ACP was established, and an analysis about a scale of facility and remote handling was accomplished. The real-time diagnostic technique was developed to detect the possible fault accidents of the slitting device. An assessment of radiation effect for various sensors was also conducted in the radiation environment.

  1. Spent fuel storage

    International Nuclear Information System (INIS)

    Huppert

    1976-01-01

    To begin with, the author explains the reasons for intermediate storage of fuel elements in nuclear power stations and in a reprocessing plant and gives the temperature and radioactivity curves of LWR fuel elements after removal from the reactor. This is followed by a description of the facilities for fuel element storage in a reprocessing plant and of their functions. Futher topics are criticality and activity control, the problem of cooling time and safety systems. (HR) [de

  2. Summary of the transportation of spent fuel attitude survey

    International Nuclear Information System (INIS)

    Roop, E.; Price, D.L.; Paquet, V.L.

    1992-01-01

    The proposed repository at Yucca Mountain, Nevada will increase highway and railway transportation of spent fuel and high level nuclear wastes. The purpose of the survey was to determine the attitudes and differences in attitudes of important actors in the transportation of spent fuel. The three major areas of investigation were 1) perceived risks associated with the transportation of spent fuel, 2) confidence in the government and others responsible for transporting spent fuel, and 3) certain transportation requirements. Response was 34.3% of the original mailing and included: 193 safety personnel, 141 employees of the nuclear industry, 260 government employees, 34 native Americans, and 9 employees of environmental organizations. This paper summarizes overall and group attitudes and opinions for the three areas mentioned above. (author)

  3. Protein enrichment of brewery spent grain from Rhizopus oligosporus by solid-state fermentation.

    Science.gov (United States)

    Canedo, Marianny Silva; de Paula, Fernanda Gomes; da Silva, Flávio Alves; Vendruscolo, Francielo

    2016-07-01

    Brewery spent grain represents approximately 85 % of total by-products generated in a brewery. Consisting of carbohydrates, fiber, minerals and low amounts of protein, the use of brewery spent grain is limited to the feeding of ruminants; however, its potential use should be investigated. The reuse of this by-product using microorganisms by solid-state fermentation process as the case of protein enrichment by single-cell protein incorporation is an alternative to ensure sustainability and generate commercially interesting products. In this context, the aim of this study was to grow Rhizopus oligosporus in brewery spent grain under different initial moisture contents and nitrogen sources to increase the protein content of the fermented material. After 7 days of fermentation, increase of 2-4 times in the crude protein and soluble protein content was verified, respectively, compared to unfermented brewery spent grain. The kinetics of protein enrichment demonstrated the possibility of application of this technique, which can be a great alternative for use in diets for animals.

  4. Spent coffee enhanced biomethane potential via an integrated hydrothermal carbonization-anaerobic digestion process.

    Science.gov (United States)

    Codignole Luz, Fábio; Volpe, Maurizio; Fiori, Luca; Manni, Alessandro; Cordiner, Stefano; Mulone, Vincenzo; Rocco, Vittorio

    2018-05-01

    This study reports the implications of using spent coffee hydrochar as substrate for anaerobic digestion (AD) processes. Three different spent coffee hydrochars produced at 180, 220 and 250 °C, 1 h residence time, were investigated for their biomethane potential in AD process inoculated with cow manure. Spent coffee hydrochars were characterized in terms of ultimate, proximate and higher heating value (HHV), and their theoretical bio-methane yield evaluated using Boyle-Buswell equation and compared to the experimental values. The results were then analyzed using the modified Gompertz equation to determine the main AD evolution parameters. Different hydrochar properties were related to AD process performances. AD of spent coffee hydrochars produced at 180 °C showed the highest biomethane production rate (46 mL CH 4 /gVS . d), a biomethane potential of 491 mL/gVS (AD lasting 25 days), and a biomethane gas daily composition of about 70%. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Microstructure Changes in a high burn up Spent Fuel (57,900 MWd/tU)

    International Nuclear Information System (INIS)

    Park, Yang Soon; Kwon, Hyoung Mun; Seo, Hang Seok; Ha, Yeong Keong; Song, Kyuseok

    2009-01-01

    In the nuclear industry, an increase in the burn up and the residence time of fuels is being considered because of the advantages in the fuel cycle cost and the spent fuel management. But, it leads to structural changes in an outer zone (rim) of a UO 2 pellet within a few hundreds of micrometers in thickness. Despite its thin layer, this rim would determine the thermal behavior of a fuel. Therefore, to identify a rim zone effect, the microstructures such as the pores, the grains and the UO 2 lattice size have been investigated by many researchers. In this study, the microstructure changes in the rim of a UO 2 spent fuel, the corrosion layer of a Zry-4 cladding and the interface between a fuel and a cladding were investigated by a micro-XRD and a SEM

  6. Predicting spent fuel oxidation states in a tuff repository

    International Nuclear Information System (INIS)

    Einziger, R.E.; Woodley, R.E.

    1987-01-01

    Nevada Nuclear Waste Storage Investigations Project (NNWSI) is studying the suitability of the tuffaceous rocks at Yucca Mountain as a waste repository for spent fuel disposal. The oxidation state of the LWR spent fuel in the moist air environment of a tuff repository could be a significant factor in determining its leaching and dissolution characteristics. Predictions as to which oxidation states would be present are important in analyzing such a repository and thus the present study was undertaken. A set of TGA (thermogravimetric analysis) tests were conducted on well-controlled samples of irradiated PWR fuel with time and temperature as the only variables. The tests were conducted between 140 and 225 0 C for a duration up to 2200 hours. The weight gain curves were analyzed in terms of diffusion through a layer of U 3 O 7 , diffusion into the grains to form a solid solution, a simplified empirical representation of a combination of grain boundary diffusion and bulk grain oxidation. Reaction rate constants were determined in each case, but analysis of these data could not establish a definitive mechanism. 21 refs., 10 figs., 3 tabs

  7. Muon tomography for imaging nuclear waste and spent fuel verification

    Energy Technology Data Exchange (ETDEWEB)

    Jonkmans, G.; Anghel, V.N.P.; Thompson, M. [Atomic Energy of Canada Limited, Chalk River (Canada)

    2010-07-01

    This paper explores the use of cosmic ray muons to image the content of, and to detect high-Z special nuclear material inside, shielded containers. Cosmic ray muons are a naturally occurring form of radiation, are highly penetrating and exhibit large scattering angles on high Z materials. Specifically, we investigated how radiographic and tomographic techniques can be effective for non-invasive nuclear waste characterization and for nuclear material accountancy of spent fuel inside dry storage containers. We show that the tracking of individual muons, as they enter and exit a structure, can potentially improve the accuracy and availability of data on nuclear waste and the content of Dry Storage Containers (DSC) used for spent fuel storage at CANDU plants. This could be achieved in near real time, with the potential for unattended and remotely monitored operations. We show that the expected sensitivity to perform material accountancy, in the case of the DSC, exceeds the IAEA detection target for nuclear material accountancy. (author)

  8. Nuclear spent fuel dry storage in the EWA reactor shaft

    International Nuclear Information System (INIS)

    Mieleszczenko, W.; Moldysz, A.; Hryczuk, A.; Matysiak, T.

    2001-01-01

    The EWA reactor was in operation from 1958 until February 1995. Then it was subjected to the decommissioning procedure. Resulting from a prolonged operation of Polish research reactors a substantial amount of nuclear spent fuel of various types, enrichment and degree of burnup have been accumulated. The technology of storage of spent nuclear fuel foresees the two stages of wet storing in a water pool (deferral period from tens to several dozens years) and dry storing (deferral period from 50 to 80 years). In our case the deferral time in the water environment is pretty significant (the oldest fuel elements have been stored in water for more than 40 years). Though the state of stored fuel elements is satisfactory, there is a real need for changing the storage conditions of spent fuel. The paper is covering the description of philosophy and conceptual design for construction of the spent fuel dry storage in the decommissioned EWA reactor shaft. (author)

  9. Application of ALARA principles to shipment of spent nuclear fuel

    International Nuclear Information System (INIS)

    Greenborg, J.; Brackenbush, L.W.; Murphy, D.W.; Burnett, R.A.; Lewis, J.R.

    1980-05-01

    The public exposure from spent fuel shipment is very low. In view of this low exposure and the perfect safety record for spent fuel shipment, existing systems can be considered satisfactory. On the other hand, occupational exposure reduction merits consideration and technology improvement to decrease dose should concentrate on this exposure. Practices that affect the age of spent fuel in shipment and the number of times the fuel must be shipped prior to disposal have the largest impact. A policy to encourage a 5-year spent fuel cooling period prior to shipment coupled with appropriate cask redesign to accommodate larger loads would be consistent with ALARA and economic principles. And finally, bypassing high population density areas will not in general reduce shipment dose

  10. An economic analysis of spent fuel management and storage

    International Nuclear Information System (INIS)

    Nagano, Koji

    1998-01-01

    Spent fuel management is becoming a key issue not only in the countries that have already experienced years of nuclear operation but also in the Asian countries that started nuclear utilization rather lately. This paper summarizes the key aspects that essentially determine optimal conditions for desired spent fuel management strategies from the engineering-economic point of view, in both national and regional perspectives. The term 'desired' is intended to highlight positive and beneficial aspects of such strategies, namely mobile and timely exploitation of spent fuel storage. Among all, the economy of scale, the economy of scope, the learning-by-doing effect, and benefits of R and D are reviewed theoretically and empirically, and the paper overviews to what extent these factors are implemented in solving spent fuel management strategy optimization problem. (author)

  11. Pt-Rh alloys. Investigation of creep rate and rupture time at high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Trumic, Biserka; Gomidzelovic, Lidija; Marjanovic, Sasa; Ivanovic, Aleksandra; Dimitrijevic, Silvana [Belgrade Univ., Bor (Serbia). Inst. of Mining and Metallurgy; Krstic, Vesna

    2013-02-01

    The results of experimental investigation of creep rate and rupture time of the alloys of Pt-Rh system are presented in this paper. Selected alloys with 7-40 wt.-% Rh content were examined using a universal device for tensile testing of materials at high temperatures, and monitoring structure changes of the samples by electron microscopy. Investigations were performed in the temperature range between 1200 C and 1700 C at a stress between 2 MPa and 15 MPa. (orig.)

  12. Time-evolution of the entropy of fluctuations in some biological systems as investigated by NMR

    International Nuclear Information System (INIS)

    Lenk, R.

    1979-01-01

    A simple expression for the entropy of fluctuations has been developed, using the tunnelling-effect model. This gives the possibility to estimate the changes and evolution of entropy in non-crystalline and biological samples by NMR investigations. On the other hand, the oscillatory character of the time-evolution of some properties, experimentally found in the investigated samples of plants, is interpreted in terms of the generalized master equation with an exponential memory function. (Auth.)

  13. Spent fuel management in Canada

    International Nuclear Information System (INIS)

    Pattantyus, P.

    1998-01-01

    The current status of the Canadian Spent Fuel Management is described. This includes wet and dry interim storage, transportation issues and future plans regarding final disposal based on deep underground emplacement in stable granite rock. Extension of wet interim storage facilities is not planned, as dry storage technologies have found wide acceptance. (author)

  14. Worldwide spent fuel transportation logistics

    International Nuclear Information System (INIS)

    Best, R.E.; Garrison, R.F.

    1978-01-01

    This paper presents an overview of the worldwide transportation requirements for spent fuel. Included are estimates of numbers and types of shipments by mode and cask type for 1985 and the year 2000. In addition, projected capital and transportation costs are presented. For the year 1977 and prior years inclusive, there is a cumulative worldwide requirement for approximately 300 MTU of spent fuel storage at away-from-reactor (AFR) facilities. The cumulative requirements for years through 1985 are projected to be nearly 10,000 MTU, and for the years through 2000 the requirements are conservatively expected to exceed 60,000 MTU. These AFR requirements may be related directly to spent fuel transportation requirements. In total nearly 77,000 total cask shipments of spent fuel will be required between 1977 and 2000. These shipments will include truck, rail, and intermodal moves with many ocean and coastal water shipments. A limited number of shipments by air may also occur. The US fraction of these is expected to include 39,000 truck shipments and 14,000 rail shipments. European shipments to regional facilities are expected to be primarily by rail or water mode and are projected to account for 16,000 moves. Pacific basin shipments will account for 4500 moves. The remaining are from other regions. Over 400 casks will be needed to meet the transportation demands. Capital investment is expected to reach $800,000,000 in 1977 dollars. Cumulative transport costs will be a staggering $4.4 billion dollars

  15. A safety study on the wet storage of spent fuel

    International Nuclear Information System (INIS)

    Chun, Kwan Sik; Whang, Joo Ho; Lee, Hoo Kun; Choi, Jong Won; Lee, Jong Geun

    1989-02-01

    This study is to provide data related with a basic design of the spent fuel storage facility in the field of radiation and to establish the safety assessment methodology of away from reactor spent fuel storage facility. This is in progress and continue upto the year of 1991. The mathematical model which predict the quantity of environmental release of fission and corrosion products from spent fuel received and stored in wet storage facility operated in normal conditions was prepared. The decay characteristic of domestic spent fuels are analysed and then the coefficients for the prediction of the decay heat by simple formular was determined. This correlations could predict decay heat of spent fuel with ±10% difference from ORIGEN2 results. The release factor of cobalt out of PWR spent fuel in PIE pool is 7.97 x 10-12∼8.49 x 10-11 Ci/ sec-rod, which appears to be linear without being connected with the types of fuel defects, but that of cesium varies with the defect type and the exposure time in water. In water condition, release factor of uranium out of CANDU fuel pellets appears to be about 5 x 10-8/day, whose tendency is similar to that of cesium of the latter half of the exposure time of water. (Author)

  16. Specialists' meeting on gas-cooled reactor fuel development and spent fuel treatment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1985-07-01

    Topics covered during the 'Specialists' meeting on gas-cooled reactor fuel development and spent fuel treatment' were as follows: Selection of constructions and materials, fuel element development concepts; Fabrication of spherical coated fuel particles and fuel element on their base; investigation of fuel properties; Spent fuel treatment and storage; Head-end processing of HTGR fuel elements; investigation of HTGR fuel regeneration process; applicability of gas-fluorine technology of regeneration of spent HTGR fuel elements.

  17. Specialists' meeting on gas-cooled reactor fuel development and spent fuel treatment

    International Nuclear Information System (INIS)

    1985-01-01

    Topics covered during the 'Specialists' meeting on gas-cooled reactor fuel development and spent fuel treatment' were as follows: Selection of constructions and materials, fuel element development concepts; Fabrication of spherical coated fuel particles and fuel element on their base; investigation of fuel properties; Spent fuel treatment and storage; Head-end processing of HTGR fuel elements; investigation of HTGR fuel regeneration process; applicability of gas-fluorine technology of regeneration of spent HTGR fuel elements

  18. Investigation of the Adaptability of Transient Stability Assessment Methods to Real-Time Operation

    OpenAIRE

    Weckesser, Johannes Tilman Gabriel; Jóhannsson, Hjörtur; Sommer, Stefan; Østergaard, Jacob

    2012-01-01

    In this paper, an investigation of the adaptability of available transient stability assessment methods to real-time operation and their real-time performance is carried out. Two approaches based on Lyapunov’s method and the equal area criterion are analyzed. The results allow to determine the runtime of each method with respect to the number of inputs. Furthermore, it allows to identify, which method is preferable in case of changes in the power system such as the integration of distributed ...

  19. Analysis of the loss of pool cooling accident in a PWR spent fuel pool with MAAP5

    International Nuclear Information System (INIS)

    Wu, Xiaoli; Li, Wei; Zhang, Yapei; Tian, Wenxi; Su, Guanghui; Qiu, Suizheng

    2014-01-01

    Highlights: • A PWR spent fuel pool was modeled by using MAAP5. • Loss of pool cooling severe accident scenarios were studied. • Loss of pool cooling accidents with two mitigation measures were analyzed. - Abstract: The Fukushima Daiichi nuclear accident shows that it is necessary to study potential severe accidents and corresponding mitigation measures for the spent fuel pool (SFP) of a nuclear power plant (NPP). This paper presents the analysis of loss of pool cooling accident scenarios and the discussion of mitigation measures for the SFP at a pressurized water reactor (PWR) NPP with the MAAP5 code. Analysis of uncompensated loss of water due to the loss of pool cooling with different initial pool water levels of 12.2 m (designated as a reference case) and 10.7 m have been performed based on a MAAP5 input model. Scenarios of the accident such as overheating of uncovered fuel assemblies, oxidation of claddings and hydrogen generation, loss of intactness of fuel rod claddings, and release of radioactive fission products were predicted with the assumption that mitigation measures were unavailable. The results covered a broad spectrum of severe accident evaluations in the SFP. Furthermore, as important mitigation measures, the effects of recovering the SFP cooling system and makeup water in SFP on the accident progressions have also been investigated respectively based on the events of pool water boiling and spent fuels uncovery. Based upon the reference case, three cases with the recovery of SFP cooling system and three other cases with makeup water in SFP have been studied. The results showed that, severe accident might happen if SFP cooling system was not restored timely before the spent fuels started to become uncovered; spent fuels could be completely submerged and severe accident might be avoided if SFP makeup water system provided water with a mass flow rate larger than the average evaporation rate defined as the division of pool water mass above the

  20. Investigation Model for DDoS Attack Detection in Real-Time

    Directory of Open Access Journals (Sweden)

    Abdulghani Ali Ahmed

    2015-02-01

    Full Text Available Investigating traffic of distributed denial of services (DDoS attack requires extra overhead which mostly results in network performance degradation. This study proposes an investigation model for detecting DDoS attack in real-time without causing negative degradation against network performance. The model investigates network traffic in a scalable way to detect user violations on quality of service regulations. Traffic investigation is triggered only when the network is congested; at that exact moment, burst gateways actually generate a congestion notification to misbehaving users. The misbehaving users are thus further investigated by measuring their consumption ratios of bandwidth. By exceeding the service level agreement bandwidth ratio, user traffic is filtered as DDoS traffic. Simulation results demonstrate that the proposed model efficiently monitors intrusive traffic and precisely detects DDoS attack.

  1. Comparative analysis of LWR and FBR spent fuels for nuclear forensics evaluation

    International Nuclear Information System (INIS)

    Permana, Sidik; Suzuki, Mitsutoshi; Su'ud, Zaki

    2012-01-01

    Some interesting issues are attributed to nuclide compositions of spent fuels from thermal reactors as well as fast reactors such as a potential to reuse as recycled fuel, and a possible capability to be manage as a fuel for destructive devices. In addition, analysis on nuclear forensics which is related to spent fuel compositions becomes one of the interesting topics to evaluate the origin and the composition of spent fuels from the spent fuel foot-prints. Spent fuel compositions of different fuel types give some typical spent fuel foot prints and can be estimated the origin of source of those spent fuel compositions. Some technics or methods have been developing based on some science and technological capability including experimental and modeling or theoretical aspects of analyses. Some foot-print of nuclear forensics will identify the typical information of spent fuel compositions such as enrichment information, burnup or irradiation time, reactor types as well as the cooling time which is related to the age of spent fuels. This paper intends to evaluate the typical spent fuel compositions of light water (LWR) and fast breeder reactors (FBR) from the view point of some foot prints of nuclear forensics. An established depletion code of ORIGEN is adopted to analyze LWR spent fuel (SF) for several burnup constants and decay times. For analyzing some spent fuel compositions of FBR, some coupling codes such as SLAROM code, JOINT and CITATION codes including JFS-3-J-3.2R as nuclear data library have been adopted. Enriched U-235 fuel composition of oxide type is used for fresh fuel of LWR and a mixed oxide fuel (MOX) for FBR fresh fuel. Those MOX fuels of FBR come from the spent fuels of LWR. Some typical spent fuels from both LWR and FBR will be compared to distinguish some typical foot-prints of SF based on nuclear forensic analysis.

  2. Comparative analysis of LWR and FBR spent fuels for nuclear forensics evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Permana, Sidik; Suzuki, Mitsutoshi; Su' ud, Zaki [Department of Science and Technology for Nuclear Material Management (STNM), Japan Atomic Energy Agency (JAEA), 2-4 Shirane, Shirakata, Tokai Mura, Naka-gun, Ibaraki 319-1195 Nuclear Physics and Bio (Indonesia); Department of Science and Technology for Nuclear Material Management (STNM), Japan Atomic Energy Agency (JAEA), 2-4 Shirane, Shirakata, Tokai Mura, Naka-gun, Ibaraki 319-1195 (Japan); Nuclear Physics and Bio Physics Research Group, Department of Physics, Bandung Institute of Technology, Gedung Fisika, Jl. Ganesha 10, Bandung 40132 (Indonesia)

    2012-06-06

    Some interesting issues are attributed to nuclide compositions of spent fuels from thermal reactors as well as fast reactors such as a potential to reuse as recycled fuel, and a possible capability to be manage as a fuel for destructive devices. In addition, analysis on nuclear forensics which is related to spent fuel compositions becomes one of the interesting topics to evaluate the origin and the composition of spent fuels from the spent fuel foot-prints. Spent fuel compositions of different fuel types give some typical spent fuel foot prints and can be estimated the origin of source of those spent fuel compositions. Some technics or methods have been developing based on some science and technological capability including experimental and modeling or theoretical aspects of analyses. Some foot-print of nuclear forensics will identify the typical information of spent fuel compositions such as enrichment information, burnup or irradiation time, reactor types as well as the cooling time which is related to the age of spent fuels. This paper intends to evaluate the typical spent fuel compositions of light water (LWR) and fast breeder reactors (FBR) from the view point of some foot prints of nuclear forensics. An established depletion code of ORIGEN is adopted to analyze LWR spent fuel (SF) for several burnup constants and decay times. For analyzing some spent fuel compositions of FBR, some coupling codes such as SLAROM code, JOINT and CITATION codes including JFS-3-J-3.2R as nuclear data library have been adopted. Enriched U-235 fuel composition of oxide type is used for fresh fuel of LWR and a mixed oxide fuel (MOX) for FBR fresh fuel. Those MOX fuels of FBR come from the spent fuels of LWR. Some typical spent fuels from both LWR and FBR will be compared to distinguish some typical foot-prints of SF based on nuclear forensic analysis.

  3. An investigation of the neutron die-away time in passive neutron waste assay systems

    International Nuclear Information System (INIS)

    Baeten, P.; Bruggeman, M.; Carchon, R.

    1997-02-01

    Neutron coincidence counting applied to the assay of Pu-bearing waste is commonly based on the assumption that the time intervals between detected fission neutrons are distributed according to a mono-exponential function, often called Rossi-alpha distribution. The time constant of this characteristic exponential function is generally referred to as the die-away time of the detector assembly. In fact, the distribution of time intervals is derived from the more fundamental arrival time distribution, which is also assumed to obey a mono-exponential law. In view of the design studies for a neutron counter, the validity of this basic assumption was investigated. Different parameters such as neutron moderation and absorption in the sample and the presence of cadmium-lining were investigated by means of Monte Carlo simulations using the NCNP-code. The simulation results lead to the conclusion that the description of the arrival time function with a mono-exponential function with a sample-independent die-away time is only a first approximations. The mono-exponential decay is perturbed by a second time component related to the detection of neutrons already thermalized in the sample. This thermal component cannot be described by a mono-exponential function, but has a characteristic shape with a fast build-up reaching a maximum followed by a slow decay as a function of the arrival time. The relative contribution of this component strongly depends on the absorption and moderation of the sample matrix. This component cannot be described by a simple analytical expression involving sample related parameters. Hence, no direct useful information can be withdrawn from the arrival time probability function to characterize the waste matrix. The thermal component can be strongly suppressed by the use of cadmium-lining in front of the detector blocks simplifying the mathematical description of the arrival time probability function. Indications of the bias introduced by an inaccurate

  4. Real time neutron transmission investigation of the austenite-bainite transformation in grey iron

    International Nuclear Information System (INIS)

    Meggers, Kay; Priesmeyer, Hans G.; Trela, Walter J.; Bowman, Charles D.; Dahms, Michael

    1994-01-01

    The first successful application of a new method to investigate phase transformations in real time, like the decomposition of austenite into bainite in grey iron, is described. During the ongoing transformation, transmission spectra of thermal neutrons, which contain Bragg edges corresponding to the crystal structure of the transforming phases, are recorded. By evaluating the height of these Bragg edges, which is a measure of the volume fraction of the phase, at different transformation times, the transformation can be followed in-situ in a time resolved manner. The method is compared to other previously used methods (micrographs, dilatometry, diffraction techniques); also a summary and an outlook are given. ((orig.))

  5. Time-Resolved WAXD and SAXS Investigations on Butyl Branched Alkane at Elevated Pressures

    NARCIS (Netherlands)

    Rastogi, A.; Hobbs, J.K.; Rastogi, S.

    2002-01-01

    The crystallization behavior and the morphological aspect of the butyl branched alkane C96H193CH(C4H9)C94H189 have been investigated using time-resolved wide-angle X-ray diffraction (WAXD) and small-angle X-ray scattering (SAXS) at atmospheric and elevated pressures. The solution crystallized sample

  6. Experimental investigation of nano-alumina effect on the filling time ...

    African Journals Online (AJOL)

    In this research, by producing composite samples made of glass fibers and epoxy resin with different percentages of nanoparticles (Nano-alumina), the adding effect of nanoparticles of alumina Alpha and Gamma grade on filling time in the vacuum assistant resin transfer molding process (VARTM) is investigated. The grade ...

  7. An Investigation of the Effectiveness and Validity of Planning Time in Speaking Test Tasks

    Science.gov (United States)

    Wigglesworth, Gillian; Elder, Cathie

    2010-01-01

    The study described in this article investigated the relationship between three variables in the IELTS oral module--planning, proficiency, and task--and was designed to enhance our understanding of how or whether these variables interact. The study aimed to determine whether differences in performance resulted from 1 or 2 min of planning time. It…

  8. Anaerobic biodegradation of spent sulphite liquor in a UASB reactor

    DEFF Research Database (Denmark)

    Jantsch, T.G.; Angelidaki, Irini; Schmidt, Jens Ejbye

    2002-01-01

    Anaerobic biodegradation of fermented spent sulphite liquor, SSL, which is produced during the manufacture of sulphite pulp, was investigated. SSL contains a high concentration of lignin products in addition to hemicellulose and has a very high COD load (173 g COD l1). Batch experiments...... ðl dÞ1 and hydraulic retention time from 3.7 to 1.5 days. The biogas productivity was 3 l ðlreactor dÞ1, with a yield of 0.05 l gas ðg VSÞ1. These results suggest that anaerobic digestion in UASB reactors may provide a new alternative for the treatment of SSL to other treatment strategies...... such as incineration. Although the total COD reduction achieved is limited, bioenergy is produced and readily biodegradable matter is removed causing less load on post-treatment installations. 2002 Elsevier Science Ltd. All rights reserved....

  9. Characterization of monolith block of spent resin cementation

    International Nuclear Information System (INIS)

    Prayitno; Endro-Kismolo; Isman MT

    1996-01-01

    Spent resin immobilization process with cement was done to prevent release of radionuclide in the ultimate storage or disposal. The varied Composition of water/cement ratio in the cementation process were 0.3; 0.4; 0.5 and the various weight of resin waste are 25 g, 37.5 g and 50 gram. The compressive strength of the various water/cement ratio without spent resin was bigger than 0.3. This investigation proved that the compressive strength of Tiga Roda cement was bigger than those of Gresik cement or Nusantara cement. The compressive of the cement block of were the spent resin cementation was influenced by the water/cement ratio and the total spent resin addition. The best condition reached at the water/cement ratio of 0.3 and 25 gram spent resin, was compressive strength of 17.86 N/mm 2 . Leaching rate of the various weight composition of spent resin cementation for 91 days were between 10 -2 - 10 -4 gram.cm -2 .day -1

  10. Development of compaction technique for spent fuel skeletons

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Ji Sup; Kim, Young Hwan; Jung, Jae Hoo [Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-12-01

    To increase the utilization of uranium resources contained in the spent fuel, the spent fuel is reused. For this, the spent fuel is dismantled or spent fuel rod is extracted from the spent fuel assembly. When the rod is extracted, the remaining components of spent fuel assembly, so called a NFBC(Non-Fuel Bearing Components), should be compacted for the final disposal. To this end, several companies developed the NFBC compactors. German company, named as GNS has developed the direct compression devices of the NFBCs for the rod consolidation and installed it at the PKA(2) of pilot conditioning plant. B and W (Babcock and Wilcox) in USA adopted cutting method rather than the compression method and developed the special cutting devices of NFBC which can be applied underwater environment. In this study the characteristics of these two methods was investigated, in terms of fabrication cost of devices, maintainability in a high radioactive environment, required power and work volume for operation. Also, the optimal power source is selected by comparing the maximum power versus the work volume for operation. In addition to these, the reduction ratio of the bulk volume is obtained while varying the cutting length of the NFBC through a series of experiments. Based on the results of analysis and experiments, the cutting method after compression is selected as an optimal volume reduction method and its design specification is obtained. 8 refs., 62 figs., 32 tabs. (Author)

  11. An overview on the nuclear spent fuel management in Romania

    International Nuclear Information System (INIS)

    Radu, M.

    2001-01-01

    The sources of radioactive waste in Romania are users of radiation and radioactive materials in industry (including nuclear electricity generation), medicine, agriculture and research and also the processing of materials that are naturally radioactive, such as uranium ores. The different types of radioactive waste are classified into four categories of waste: excepted waste, low level waste, medium level waste and high level waste. A spent fuel management sub-programme as a part of the Radioactive Waste Management programme was initiated by the former Romanian Electricity Company (RENEL) in 1992. Within the frame of R and D of the Radioactive Waste and Spent Fuel Management Programme, the topics cover investigations, studies and research to identify the sites and the conceptual designs for a Spent Fuel Interim Storage Facility (SFISF) and also a Spent Fuel Disposal Facility (SFDF). Changes in the organization of the nuclear activities of RENEL, involving both responsibilities and financing aspects, led to interruption of the programme. The programme includes study of the main methods and the existing technologies for the design, operation and safety of an interim storage facility (including transport aspects). It also includes analysis of details on the site selection for this facility and for a spent fuel final disposal facility. The achievement of the spent fuel interim storage facility is proceeding. The results from the studies performed in the last years will permit us to prepare the feasibility study next year and the documentation required by our regulatory body for starting the process to obtain a license for a SFISF at Cernavoda. A second phase is the assessment of a long term strategy to select and adopt a proven disposal technology for spent fuel, corresponding with a selected site. The status of the work performed in the frame of this programme and also the situation of the spent fuel from research reactors are presented. (author)

  12. MTR radiological database for SRS spent nuclear fuel facilities

    International Nuclear Information System (INIS)

    Blanchard, A.

    2000-01-01

    A database for radiological characterization of incoming Material Test Reactor (MTR) fuel has been developed for application to the Receiving Basin for Offsite Fuels (RBOF) and L-Basin spent fuel storage facilities at the Savannah River Site (SRS). This database provides a quick quantitative check to determine if SRS bound spent fuel is radiologically bounded by the Reference Fuel Assembly used in the L-Basin and RBOF authorization bases. The developed database considers pertinent characteristics of domestic and foreign research reactor fuel including exposure, fuel enrichment, irradiation time, cooling time, and fuel-to-moderator ratio. The supplied tables replace the time-consuming studies associated with authorization of SRS bound spent fuel with simple hand calculations. Additionally, the comprehensive database provides the means to overcome resource limitations, since a series of simple, yet conservative, hand calculations can now be performed in a timely manner and replace computational and technical staff requirements

  13. Moral and Property Harm as Consequence of Violation of Reasonable Time of Preliminary Investigation

    Directory of Open Access Journals (Sweden)

    Ibiamin N. Nuriev

    2017-08-01

    Full Text Available The relevance of the article is that it examines the provisions of the criminal procedure law on a reasonable time of preliminary investigation, the consequences of violation of a reasonable period of preliminary investigation. A formula is proposed that makes it possible to make a clearer idea of a reasonable time as a border in the criminal procedural time between conditionally permitted and absolutely unacceptable. In the Author's opinion, the consequences of a violation of a reasonable period is the person's moral and (or property damage. The Author recommends that in the Federal Law of April 30, 2010, No. 68-FZ, replace the concept of “significance of consequences” with the notion of “harm”.

  14. Cognitive load and task condition in event- and time-based prospective memory: an experimental investigation.

    Science.gov (United States)

    Khan, Azizuddin; Sharma, Narendra K; Dixit, Shikha

    2008-09-01

    Prospective memory is memory for the realization of delayed intention. Researchers distinguish 2 kinds of prospective memory: event- and time-based (G. O. Einstein & M. A. McDaniel, 1990). Taking that distinction into account, the present authors explored participants' comparative performance under event- and time-based tasks. In an experimental study of 80 participants, the authors investigated the roles of cognitive load and task condition in prospective memory. Cognitive load (low vs. high) and task condition (event- vs. time-based task) were the independent variables. Accuracy in prospective memory was the dependent variable. Results showed significant differential effects under event- and time-based tasks. However, the effect of cognitive load was more detrimental in time-based prospective memory. Results also revealed that time monitoring is critical in successful performance of time estimation and so in time-based prospective memory. Similarly, participants' better performance on the event-based prospective memory task showed that they acted on the basis of environment cues. Event-based prospective memory was environmentally cued; time-based prospective memory required self-initiation.

  15. Spent Fuel Transfer to Dry Storage Using Unattended Monitoring System

    International Nuclear Information System (INIS)

    Park, Jae Hwan; Park, Soo Jin

    2009-01-01

    There are 4 CANDU reactors at Wolsung site together with a spent fuel dry storage associated with unit 1. These CANDU reactors, classified as On-Load Reactor (OLR) for Safeguards application, change 16- 24 fuel bundles with fresh fuel in everyday. Especially, the spent fuel bundles are transferred from spent fuel bays to dry storage throughout a year because of the insufficient capacity of spent fuel pond. Safeguards inspectors verify the spent fuel transfer to meet safeguards purposes according to the safeguards criteria by means of inspector's presence during the transfer campaign. For the verification, 60-80 person-days of inspection (PDIs) are needed during approximately 3 months for each unit. In order to reduce the inspection effort and operators' burden, an Unattended Monitoring System (UMS) was designed and developed by the IAEA for the verification of spent fuel bundles transfers from wet storage to dry storage. Based on the enhanced cooperation of CANDU reactors between the ROK and the IAEA, the IAEA installed the UMS at Wolsung unit 2 in January 2005 at first. After some field trials during the transfer campaign, this system is being replaced the traditional human inspection since September 1, 2006 combined with a Short Notice Inspection (SNI) and a near-real time Mailbox Declaration

  16. Conditioning of spent nuclear fuel for permanent disposal

    International Nuclear Information System (INIS)

    Laidler, J.J.

    1994-01-01

    A compact, efficient method for conditioning spent nuclear fuel is under development This method, known as pyrochemical processing, or open-quotes pyroprocessing,close quotes provides a separation of fission products from the actinide elements present in spent fuel and further separates pure uranium from the transuranic elements. The process can facilitate the timely and environmentally-sound treatment of the highly diverse collection of spent fuel currently in the inventory of the United States Department of Energy (DOE). The pyroprocess utilizes elevated-temperature processes to prepare spent fuel for fission product separation; that separation is accomplished by a molten salt electrorefining step that provides efficient (99.9%) separation of transuranics. The resultant waste forms from the pyroprocess are stable under envisioned repository environment conditions and highly leach-resistant. Treatment of any spent fuel type produces a set of common high-level waste forms, one a mineral and the other a metal alloy, that can be readily qualified for repository disposal and preclude the substantial costs that would be associated with the qualification of the numerous spent fuel types included in the DOE inventory

  17. Conditioning of spent nuclear fuel for permanent disposal

    International Nuclear Information System (INIS)

    Laidler, J.J.

    1994-01-01

    A compact, efficient method for conditioning spent nuclear fuel is under development. This method, known as pyrochemical processing, or pyroprocessing, provides a separation of fission products from the actinide elements present in spent fuel and further separates pure uranium from the transuranic elements. The process can facilitate the timely and environmentally-sound treatment of the highly diverse collection of spent fuel currently in the inventory of the US Department of Energy (DOE). The pyroprocess utilizes elevated-temperature processes to prepare spent fuel for fission product separation; that separation is accomplished by a molten salt electrorefining step that provides efficient (> 99.9%) separation of transuranics. The resultant waste forms from the pyroprocess are stable under envisioned repository environment conditions and highly leach-resistant. Treatment of any spent fuel type produces a set of common high-level waste forms, one a mineral and the other a metal alloy, that can be readily qualified for repository disposal and that avoid the substantial costs that would be associated with the qualification of the numerous spent fuel types included in the DOE inventory

  18. Collective processing device for spent fuel

    International Nuclear Information System (INIS)

    Irie, Hiroaki; Taniguchi, Noboru.

    1996-01-01

    The device of the present invention comprises a sealing vessel, a transporting device for transporting spent fuels to the sealing vessel, a laser beam cutting device for cutting the transported spent fuels, a dissolving device for dissolving the cut spent fuels, and a recovering device for recovering radioactive materials from the spent fuels during processing. Reprocessing treatments comprising each processing of dismantling, shearing and dissolving are conducted in the sealing vessel can ensure a sealing barrier for the radioactive materials (fissionable products and heavy nuclides). Then, since spent fuels can be processed in a state of assemblies, and the spent fuels are easily placed in the sealing vessel, operation efficiency is improved, as well as operation cost is saved. Further, since the spent fuels can be cut by a remote laser beam operation, there can be prevented operator's exposure due to radioactive materials released from the spent fuels during cutting operation. (T.M.)

  19. An investigation of fMRI time series stationarity during motor sequence learning foot tapping tasks.

    Science.gov (United States)

    Muhei-aldin, Othman; VanSwearingen, Jessie; Karim, Helmet; Huppert, Theodore; Sparto, Patrick J; Erickson, Kirk I; Sejdić, Ervin

    2014-04-30

    Understanding complex brain networks using functional magnetic resonance imaging (fMRI) is of great interest to clinical and scientific communities. To utilize advanced analysis methods such as graph theory for these investigations, the stationarity of fMRI time series needs to be understood as it has important implications on the choice of appropriate approaches for the analysis of complex brain networks. In this paper, we investigated the stationarity of fMRI time series acquired from twelve healthy participants while they performed a motor (foot tapping sequence) learning task. Since prior studies have documented that learning is associated with systematic changes in brain activation, a sequence learning task is an optimal paradigm to assess the degree of non-stationarity in fMRI time-series in clinically relevant brain areas. We predicted that brain regions involved in a "learning network" would demonstrate non-stationarity and may violate assumptions associated with some advanced analysis approaches. Six blocks of learning, and six control blocks of a foot tapping sequence were performed in a fixed order. The reverse arrangement test was utilized to investigate the time series stationarity. Our analysis showed some non-stationary signals with a time varying first moment as a major source of non-stationarity. We also demonstrated a decreased number of non-stationarities in the third block as a result of priming and repetition. Most of the current literature does not examine stationarity prior to processing. The implication of our findings is that future investigations analyzing complex brain networks should utilize approaches robust to non-stationarities, as graph-theoretical approaches can be sensitive to non-stationarities present in data. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Reclamation of alkaline spent moulding sands of organic and inorganic type and their mixtures

    Directory of Open Access Journals (Sweden)

    R. Dańko

    2011-10-01

    Full Text Available Introduction of modern moulding sands with organic and inorganic binders requires the reclamation treatments in order to be able to reuse the matrices of spent sands. The spent sands, depending on the applied binding agent, are characterised by various abilities of the matrix reclamation. The results of investigations of the reclamation of spent moulding sands with the Rudal binder and spent sands with the Rezolit binder in the system of uniform sands and of mixed ones, are presented in the paper. Investigations were performed by means of the special experimental stands designed and built in the AGH University of Science and Technology, AGH, in Krakow.

  1. Applied measuring techniques for the investigation of time-dependent flow phenomena in centrifugal compressors

    International Nuclear Information System (INIS)

    Hass, U.; Haupt, U.; Jansen, M.; Kassens, K.; Knapp, P.; Rautenberg, M.

    1978-01-01

    During the past 10 years new measuring techniques have been developed for the experimental investigation of highly loaded centrifugal compressors. These measuring techniques take into account the time dependency of the fluctuating physical quantities such as pressure, temperature, and velocity. Some key points of these experimental techniques are shown and explained in this paper. An important basis for such measurements is the accurate dynamic calibration of the measuring apparatus. In addition, some problems involved analyzing measured signals are dealt with and pressure measurements and their interpretation are shown. Finally optical, acoustical and vibrational measuring procedures are described which are additionally used for the investigation of non-stationary flow phenomena. (orig.) [de

  2. Investigation of a Multi-Anode Microchannel Plate PMT for Time-of-Flight PET

    Science.gov (United States)

    Choong, Woon-Seng

    2010-10-01

    We report on an investigation of a mulit-anode microchannel plate PMT for time-of-flight PET detector modules. The primary advantages of an MCP lie in its excellent timing properties (fast rise time and low transit time spread), compact size, and reasonably large active area, thus making it a good candidate for TOF applications. In addition, the anode can be segmented into an array of collection electrodes with fine pitch to attain good position sensitivity. In this paper, we investigate using the Photonis Planacon MCP-PMT with a pore size of 10 μm to construct a PET detector module, specifically for time-of-flight applications. We measure the single electron response by exciting the Planacon with pulsed laser diode. We also measure the performance of the Planacon as a PET detector by coupling a 4 mm×4 mm×10 mm LSO crystal to individual pixel to study its gain uniformity, energy resolution, and timing resolution. The rise time of the Planacon is 440 ps with pulse duration of about 1 ns. A transit time spread of 120 ps FWHM is achieved. The gain is fairly uniform across the central region of the Planacon, but drops off by as much as a factor of 2.5 around the edges. The energy resolution is fairly uniform across the Planacon with an average value of 18.6 ± 0.7% FWHM. While the average timing resolution of 252 ± 7 ps FWHM is achieved in the central region of the Planacon, it degrades to 280 ± 9 ps FWHM for edge pixels and 316 ± 15 ps FWHM for corner pixels. We compare the results with measurements performed with a fast timing conventional PMT (Hamamatsu R-9800). We find that the R9800, which has significantly higher PDE, has a better timing resolution than the Planacon. Furthermore, we perform detector simulations to calculate the improvement that can be achieved with a higher PDE Planacon. The calculation shows that the Planacon can achieve significantly better timing resolution if it can attain the same PDE as the R-9800, while only a 30% improvement is

  3. TMI-2 spent fuel shipping

    International Nuclear Information System (INIS)

    Quinn, G.J.; Burton, H.M.

    1985-01-01

    TMI-2 failed fuel will be shipped to the Idaho National Engineering Laboratory for use in the DOE Core Examination Program. The fuel debris will be loaded into three types of canisters during defueling and dry loaded into a spent fuel shipping cask. The cask design accommodates seven canisters per cask and has two separate containment vessels with ''leaktight'' seals. Shipments are expectd to begin in early 1986

  4. Reuse of Hydrotreating Spent Catalyst

    International Nuclear Information System (INIS)

    Habib, A.M.; Menoufy, M.F.; Amhed, S.H.

    2004-01-01

    All hydro treating catalysts used in petroleum refining processes gradually lose activity through coking, poisoning by metal, sulfur or halides or lose surface area from sintering at high process temperatures. Waste hydrotreating catalyst, which have been used in re-refining of waste lube oil at Alexandria Petroleum Company (after 5 years lifetime) compared with the same fresh catalyst were used in the present work. Studies are conducted on partial extraction of the active metals of spent catalyst (Mo and Ni) using three leaching solvents,4% oxidized oxalic acid, 10% aqueous sodium hydroxide and 10% citric acid. The leaching experiments are conducting on the de coked extrude [un crushed] spent catalyst samples. These steps are carried out in order to rejuvenate the spent catalyst to be reused in other reactions. The results indicated that 4% oxidized oxalic acid leaching solution gave total metal removal 45.6 for de coked catalyst samples while NaOH gave 35% and citric acid gave 31.9 % The oxidized leaching agent was the most efficient leaching solvent to facilitate the metal removal, and the rejuvenated catalyst was characterized by the unchanged crystalline phase The rejuvenated catalyst was applied for hydrodesulfurization (HDS) of vacuum gas oil as a feedstock, under different hydrogen pressure 20-80 bar in order to compare its HDS activity

  5. Spent nuclear fuel in Bulgaria

    International Nuclear Information System (INIS)

    Peev, P.; Kalimanov, N.

    1999-01-01

    The development of the nuclear energy sector in Bulgaria is characterized by two major stages. The first stage consisted of providing a scientific basis for the programme for development of the nuclear energy sector in the country and was completed with the construction of an experimental water-water reactor. At present, spent nuclear fuel from this reactor is placed in a water filled storage facility and will be transported back to Russia. The second stage consisted of the construction of the 6 NPP units at the Kozloduy site. The spent nuclear fuel from the six units is stored in at reactor pools and in an additional on-site storage facility which is nearly full. In order to engage the government of the country with the on-site storage problems, the new management of the National Electric Company elaborated a policy on nuclear fuel cycle and radioactive waste management. The underlying policy is de facto the selection of the 'deferred decision' option for its spent fuel management. (author)

  6. Spent nuclear fuel storage vessel

    International Nuclear Information System (INIS)

    Watanabe, Yoshio; Kashiwagi, Eisuke; Sekikawa, Tsutomu.

    1997-01-01

    Containing tubes for containing spent nuclear fuels are arranged vertically in a chamber. Heat releasing fins are disposed horizontal to the outer circumference of the containing tubes for rectifying cooling air and promoting cooling of the containing tubes. Louvers and evaporation sides of heat pipes are disposed at a predetermined distance in the chamber. Cooling air flows from an air introduction port to the inside of the chamber and takes heat from the containing tubes incorporated with heat generating spent nuclear fuels, rising its temperature and flows off to an air exhaustion exit. The direction for the rectification plate of the louver is downward from a horizontal position while facing to the air exhaustion port. Since the evaporation sides of the heat pipes are disposed in the inside of the chamber and the condensation side of the heat pipes is disposed to the outside of the chamber, the thermal energy can be recovered from the containing tubes incorporated with spent nuclear fuels and utilized. (I.N.)

  7. Optimization of chemical regeneration procedures of spent activated carbon

    Directory of Open Access Journals (Sweden)

    Naser Ghasemzadeh

    2017-01-01

    Full Text Available The chemical regeneration of granular activated carbon exhausted in a petrochemical wastewater unit was investigated. Gas chromatography and energy-dispersive X-ray spectroscopy demonstrated that spent activated carbon carries large types of organic and inorganic materials. Diverse chemical solvents were adopted in comparison with traditional chemical solvents and regeneration efficiency was investigated for each approach. The optimum procedure and optimum condition including temperature, concentration of solvent, and time were determined. The regenerated activated carbon was used in the adsorption of methylene blue (MB in order to find its regeneration efficiency. The regeneration efficiency can be identified by comparing of amount of MB absorbed by the fresh and regenerated activated carbon. The best acidic regenerator was hydrofluoric acid. The higher the temperature causes the faster desorption rate and consequently, the higher regeneration efficiency. The regeneration efficiency increased by means of an increase in the time of regeneration and solvent concentration, but there was an optimum time and solvent concentration for regeneration. The optimum temperature, solvent concentration and regeneration time obtained was 80 ⁰C, 3 molar and 3 hours, respectively.

  8. Modular dry storage of spent fuel

    International Nuclear Information System (INIS)

    Baxter, J.W.

    1982-01-01

    Long term uncertainties in US spent fuel reprocessing and storage policies and programs are forcing the electric utilities to consider means of storing spent fuel at the reactor site in increasing quantitities and for protracted periods. Utilities have taken initial steps in increasing storage capacity. Existing wet storage pools have in many cases been reracked to optimize their capacity for storing spent fuel assemblies

  9. Spent fuel storage process equipment development

    International Nuclear Information System (INIS)

    Park, Hyun Soo; Lee, Jae Sol; Yoo, Jae Hyung

    1990-02-01

    Nuclear energy which is a major energy source of national energy supply entails spent fuels. Spent fuels which are high level radioactive meterials, are tricky to manage and need high technology. The objectives of this study are to establish and develop key elements of spent fuel management technologies: handling equipment and maintenance, process automation technology, colling system, and cleanup system. (author)

  10. Advances in high-order harmonic generation sources for time-resolved investigations

    Energy Technology Data Exchange (ETDEWEB)

    Reduzzi, Maurizio [Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Institute of Photonics and Nanotechnologies, CNR-IFN, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Carpeggiani, Paolo [Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Kühn, Sergei [ELI-ALPS, ELI-Hu Kft., Dugonics ter 13, H-6720 Szeged (Hungary); Calegari, Francesca [Institute of Photonics and Nanotechnologies, CNR-IFN, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Nisoli, Mauro; Stagira, Salvatore [Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Institute of Photonics and Nanotechnologies, CNR-IFN, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Vozzi, Caterina [Institute of Photonics and Nanotechnologies, CNR-IFN, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Dombi, Peter [ELI-ALPS, ELI-Hu Kft., Dugonics ter 13, H-6720 Szeged (Hungary); Wigner Research Center for Physics, 1121 Budapest (Hungary); Kahaly, Subhendu [ELI-ALPS, ELI-Hu Kft., Dugonics ter 13, H-6720 Szeged (Hungary); Tzallas, Paris; Charalambidis, Dimitris [ELI-ALPS, ELI-Hu Kft., Dugonics ter 13, H-6720 Szeged (Hungary); Foundation for Research and Technology – Hellas, Institute of Electronic Structure and Lasers, P.O. Box 1527, GR-711 10 Heraklion, Crete (Greece); Varju, Katalin [ELI-ALPS, ELI-Hu Kft., Dugonics ter 13, H-6720 Szeged (Hungary); Department of Optics and Quantum Electronics, University of Szeged, Dóm tér 9, 6720 Szeged (Hungary); Osvay, Karoly [ELI-ALPS, ELI-Hu Kft., Dugonics ter 13, H-6720 Szeged (Hungary); and others

    2015-10-15

    We review the main research directions ongoing in the development of extreme ultraviolet sources based on high-harmonic generation for the synthesization and application of trains and isolated attosecond pulses to time-resolved spectroscopy. A few experimental and theoretical works will be discussed in connection to well-established attosecond techniques. In this context, we present the unique possibilities offered for time-resolved investigations on the attosecond timescale by the new Extreme Light Infrastructure Attosecond Light Pulse Source, which is currently under construction.

  11. Advances in high-order harmonic generation sources for time-resolved investigations

    International Nuclear Information System (INIS)

    Reduzzi, Maurizio; Carpeggiani, Paolo; Kühn, Sergei; Calegari, Francesca; Nisoli, Mauro; Stagira, Salvatore; Vozzi, Caterina; Dombi, Peter; Kahaly, Subhendu; Tzallas, Paris; Charalambidis, Dimitris; Varju, Katalin; Osvay, Karoly

    2015-01-01

    We review the main research directions ongoing in the development of extreme ultraviolet sources based on high-harmonic generation for the synthesization and application of trains and isolated attosecond pulses to time-resolved spectroscopy. A few experimental and theoretical works will be discussed in connection to well-established attosecond techniques. In this context, we present the unique possibilities offered for time-resolved investigations on the attosecond timescale by the new Extreme Light Infrastructure Attosecond Light Pulse Source, which is currently under construction.

  12. Investigating time-efficiency of forward masking paradigms for estimating basilar membrane input-output characteristics

    DEFF Research Database (Denmark)

    Fereczkowski, Michal; Jepsen, Morten Løve; Dau, Torsten

    2017-01-01

    -output (I/O) function have been proposed. However, such measures are very time consuming. The present study investigated possible modifications of the temporal masking curve (TMC) paradigm to improve time and measurement efficiency. In experiment 1, estimates of knee point (KP) and compression ratio (CR......”, was tested. In contrast to the standard TMC paradigm, the maker level was kept fixed and the “gap threshold” was obtained, such that the masker just masks a low-level (12 dB sensation level) signal. It is argued that this modification allows for better control of the tested stimulus level range, which...

  13. Towards investigation of evolution of dynamical systems with independence of time accuracy: more classes of systems

    Science.gov (United States)

    Gurzadyan, V. G.; Kocharyan, A. A.

    2015-07-01

    The recently developed method (Paper 1) enabling one to investigate the evolution of dynamical systems with an accuracy not dependent on time is developed further. The classes of dynamical systems which can be studied by that method are much extended, now including systems that are: (1) non-Hamiltonian, conservative; (2) Hamiltonian with time-dependent perturbation; (3) non-conservative (with dissipation). These systems cover various types of N-body gravitating systems of astrophysical and cosmological interest, such as the orbital evolution of planets, minor planets, artificial satellites due to tidal, non-tidal perturbations and thermal thrust, evolving close binary stellar systems, and the dynamics of accretion disks.

  14. MELCOR Modeling of Air-Cooled PWR Spent Fuel Assemblies in Water empty Fuel Pools

    Energy Technology Data Exchange (ETDEWEB)

    Herranz, L. E.; Lopez, C.

    2013-07-01

    The OECD Spent Fuel Project (SFP) investigated fuel degradation in case of a complete Loss-Of- Coolant-Accident in a PWR spent fuel pool. Analyses of the SFP PWR ignition tests have been conducted with the 1.86.YT.3084.SFP MELCOR version developed by SNL. The main emphasis has been placed on assessing the MELCOR predictive capability to get reasonable estimates of time-to-ignition and fire front propagation under two configurations: hot neighbor (i.e., adiabatic scenario) and cold neighbor (i.e., heat transfer to adjacent fuel assemblies). A detailed description of hypotheses and approximations adopted in the MELCOR model are provided in the paper. MELCOR results accuracy was notably different between both scenarios. The reasons are highlighted in the paper and based on the results understanding a set of remarks concerning scenarios modeling is given.

  15. Criminal investigations: pupil pharmacological reactivity as method for assessing time since death is fallacious.

    Science.gov (United States)

    Orrico, Marco; Melotti, Roberto; Mantovani, Anna; Avesani, Barbara; De Marco, Roberto; De Leo, Domenico

    2008-12-01

    Determination of the time since death in the early postmortem period is one of the most critical issues to be faced by criminal investigators. One of the techniques is the evaluation of the pupil pharmacological reactivity. In the present work, we aim at identifying whether an objective and single method, based on pharmacological pupil reaction, is feasible or not. Between 2002 and 2003 calendar years, we observed 309 bodies, whose eyes have been each instilled apart, within 26 hours since death, with either a myotic substance or a mydriatic solution. Our results show that the real effectiveness of pupil pharmacological reactivity as method for assessing the time since death in early postmortem period is not only questionable but even highly misleading if not replaced by alternative objective physiological tests and appropriate professional judgments by the investigators.

  16. Investigation of interfacial wave structure using time-series analysis techniques

    International Nuclear Information System (INIS)

    Jayanti, S.; Hewitt, G.F.; Cliffe, K.A.

    1990-09-01

    The report presents an investigation into the interfacial structure in horizontal annular flow using spectral and time-series analysis techniques. Film thickness measured using conductance probes shows an interesting transition in wave pattern from a continuous low-frequency wave pattern to an intermittent, high-frequency one. From the autospectral density function of the film thickness, it appears that this transition is caused by the breaking up of long waves into smaller ones. To investigate the possibility of the wave structure being represented as a low order chaotic system, phase portraits of the time series were constructed using the technique developed by Broomhead and co-workers (1986, 1987 and 1989). These showed a banded structure when waves of relatively high frequency were filtered out. Although these results are encouraging, further work is needed to characterise the attractor. (Author)

  17. Investigating the combined effects of heat and lighting on students reaction time in laboratory condition

    Directory of Open Access Journals (Sweden)

    Zohre Mohebian

    2016-12-01

    Full Text Available Introduction: In many workplaces there is exposure to heat and light simultaneously. This study investigated the combined effect of heat and lighting on some cognitive performance, i.e. reaction time. Methodology: the present semi-experimental study was conducted 2015 on 33 healthy students (16 girls and 17 boys with a mean age of 22.1 in the thermal stress chamber. The reaction time parameter by the reaction time measurement device, after exposure to different heat surfaces (dry temperatures 22 °C and 37 °C and lighting surfaces (200, 500 and 1500 lux. Data were analyzed using ANOVA test in SPSS-20. Results: The results showed that the average simple, diagnostic, two-color selective, two-sound selective reaction times and reaction time error increased after combined exposure to heat and lighting and showed a significant difference (P<0.05. The maximum score of reaction time belong to temperature of 37 c° and lighting of 1500 lux, the minimum score of reaction time belong to temperature of 22 °c and lighting of 1500 lux.

  18. Preliminary Investigation of Time Remaining Display on the Computer-based Emergency Operating Procedure

    Science.gov (United States)

    Suryono, T. J.; Gofuku, A.

    2018-02-01

    One of the important thing in the mitigation of accidents in nuclear power plant accidents is time management. The accidents should be resolved as soon as possible in order to prevent the core melting and the release of radioactive material to the environment. In this case, operators should follow the emergency operating procedure related with the accident, in step by step order and in allowable time. Nowadays, the advanced main control rooms are equipped with computer-based procedures (CBPs) which is make it easier for operators to do their tasks of monitoring and controlling the reactor. However, most of the CBPs do not include the time remaining display feature which informs operators of time available for them to execute procedure steps and warns them if the they reach the time limit. Furthermore, the feature will increase the awareness of operators about their current situation in the procedure. This paper investigates this issue. The simplified of emergency operating procedure (EOP) of steam generator tube rupture (SGTR) accident of PWR plant is applied. In addition, the sequence of actions on each step of the procedure is modelled using multilevel flow modelling (MFM) and influenced propagation rule. The prediction of action time on each step is acquired based on similar case accidents and the Support Vector Regression. The derived time will be processed and then displayed on a CBP user interface.

  19. Capabilities for processing shipping casks at spent fuel storage facilities

    International Nuclear Information System (INIS)

    Baker, W.H.; Arnett, L.M.

    1978-01-01

    Spent fuel is received at a storage facility in heavily shielded casks transported either by rail or truck. The casks are inspected, cooled, emptied, decontaminated, and reshipped. The spent fuel is transferred to storage. The number of locations or space inside the building provided to perform each function in cask processing will determine the rate at which the facility can process shipping casks and transfer spent fuel to storage. Because of the high cost of construction of licensed spent fuel handling and storage facilities and the difficulty in retrofitting, it is desirable to correctly specify the space required. In this paper, the size of the cask handling facilities is specified as a function of rate at which spent fuel is received for storage. The minimum number of handling locations to achieve a given throughput of shipping casks has been determined by computer simulation of the process. The simulation program uses a Monte Carlo technique in which a large number of casks are received at a facility with a fixed number of handling locations in each process area. As a cask enters a handling location, the time to process the cask at that location is selected at random from the distribution of process time. Shipping cask handling times are based on experience at the General Electric Storage Facility, Morris, Illinois. Shipping cask capacity is based on the most recent survey available of the expected capability of reactors to handle existing rail or truck casks

  20. A near-infrared, optical, and ultraviolet polarimetric and timing investigation of complex equatorial dusty structures

    Science.gov (United States)

    Marin, F.; Rojas Lobos, P. A.; Hameury, J. M.; Goosmann, R. W.

    2018-05-01

    Context. From stars to active galactic nuclei, many astrophysical systems are surrounded by an equatorial distribution of dusty material that is, in a number of cases, spatially unresolved even with cutting edge facilities. Aims: In this paper, we investigate if and how one can determine the unresolved and heterogeneous morphology of dust distribution around a central bright source using time-resolved polarimetric observations. Methods: We used polarized radiative transfer simulations to study a sample of circumnuclear dusty morphologies. We explored a grid of geometrically variable models that are uniform, fragmented, and density stratified in the near-infrared, optical, and ultraviolet bands, and we present their distinctive time-dependent polarimetric signatures. Results: As expected, varying the structure of the obscuring equatorial disk has a deep impact on the inclination-dependent flux, polarization degree and angle, and time lags we observe. We find that stratified media are distinguishable by time-resolved polarimetric observations, and that the expected polarization is much higher in the infrared band than in the ultraviolet. However, because of the physical scales imposed by dust sublimation, the average time lags of months to years between the total and polarized fluxes are important; these time lags lengthens the observational campaigns necessary to break more sophisticated, and therefore also more degenerated, models. In the ultraviolet band, time lags are slightly shorter than in the infrared or optical bands, and, coupled to lower diluting starlight fluxes, time-resolved polarimetry in the UV appears more promising for future campaigns. Conclusions: Equatorial dusty disks differ in terms of inclination-dependent photometric, polarimetric, and timing observables, but only the coupling of these different markers can lead to inclination-independent constraints on the unresolved structures. Even though it is complex and time consuming, polarized

  1. Time-resolved interaction investigations of carbocyanine dyes and chlorophyll a in solution

    International Nuclear Information System (INIS)

    Feller, K.H.; Fassler, D.

    1983-01-01

    Using a Nd:YAG laser/streak camera system of 30 ps time resolution the quenching of the fluorescence of the carbocyanine dye ICC by chlorophyll a in methanolic solution was investigated. The fluorescence lifetime of ICC decreased within the chlorophyll concentration range 0 - 9x10 - 5 mol/l from 170 ps to 135 ps. The observed very effective fluorescence quenching process suggests that the formation of heteroaggregates from ICC and chlorophyll is responsible for the rapid energy transfer. (author)

  2. The nitrate time bomb: a numerical way to investigate nitrate storage and lag time in the unsaturated zone.

    Science.gov (United States)

    Wang, L; Butcher, A S; Stuart, M E; Gooddy, D C; Bloomfield, J P

    2013-10-01

    Nitrate pollution in groundwater, which is mainly from agricultural activities, remains an international problem. It threatens the environment, economics and human health. There is a rising trend in nitrate concentrations in many UK groundwater bodies. Research has shown it can take decades for leached nitrate from the soil to discharge into groundwater and surface water due to the 'store' of nitrate and its potentially long travel time in the unsaturated and saturated zones. However, this time lag is rarely considered in current water nitrate management and policy development. The aim of this study was to develop a catchment-scale integrated numerical method to investigate the nitrate lag time in the groundwater system, and the Eden Valley, UK, was selected as a case study area. The method involves three models, namely the nitrate time bomb-a process-based model to simulate the nitrate transport in the unsaturated zone (USZ), GISGroundwater--a GISGroundwater flow model, and N-FM--a model to simulate the nitrate transport in the saturated zone. This study answers the scientific questions of when the nitrate currently in the groundwater was loaded into the unsaturated zones and eventually reached the water table; is the rising groundwater nitrate concentration in the study area caused by historic nitrate load; what caused the uneven distribution of groundwater nitrate concentration in the study area; and whether the historic peak nitrate loading has reached the water table in the area. The groundwater nitrate in the area was mainly from the 1980s to 2000s, whilst the groundwater nitrate in most of the source protection zones leached into the system during 1940s-1970s; the large and spatially variable thickness of the USZ is one of the major reasons for unevenly distributed groundwater nitrate concentrations in the study area; the peak nitrate loading around 1983 has affected most of the study area. For areas around the Bowscar, Beacon Edge, Low Plains, Nord Vue

  3. Behaviour of Spent WWER fuel under long term storage conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kadarmetov, I M [A.A.Bochvar All-Russia Research Institute of Inorganic Materials, Moscow (Russian Federation)

    1999-07-02

    Results of experimental investigation into thermomechanical properties of pre-irradiated Zr-1%Nb alloy over a range temperatures 500-570 grad C are presented. Safety examination of the Ventilation Storage Casks dry storage system has been carried out. Preliminary safety criteria under dry storage conditions in an environment of inert gas are follows: maximum cladding temperature under normal conditions of dry storage should not exceed 330 grad C after 5-year cooling in water-filled pools; maximum allowable temperature of spent fuel rod cladding under operational mode with infringement of heat removal should not exceed 440 grad C over 8 hours. As each SFA dry storage project comprises its individual technology of spent fuel management, it is necessary to evaluate allowable parameters (terms of storage, maximum temperatures of fuel) for each project respectively. The programme of experimental investigations for the justification of safety criteria for WWER-1000 dry spent fuel storage systems is underway. (author)

  4. Spent fuel pool cleanup and stabilization

    International Nuclear Information System (INIS)

    Miller, R.L.

    1987-06-01

    Each of the plutonium production reactors at Hanford had a large water-filled spent fuel pool to provide interim storage of irradiated fuel while awaiting shipment to the separation facilities. After cessation of reactor operations the fuel was removed from the pools and the water levels were drawn down to a 5- to 10-foot depth. The pools were maintained with the water to provide shielding and radiological control. What appeared to be a straightforward project to process the water, remove the sediments from the basin, and stabilize the contamination on the floors and walls became a very complex and time consuming operation. The sediment characteristics varied from pool to pool, the ion exchange system required modification, areas of hard-pack sediments were discovered on the floors, special arrangements to handle and package high dose rate items for shipment were required, and contract problems ensued with the subcontractor. The original schedule to complete the project from preliminary engineering to final stabilization of the pools was 15 months. The actual time required was about 25 months. The original cost estimate to perform the work was $2,651,000. The actual cost of the project was $5,120,000, which included $150,000 for payment of claims to the subcontractor. This paper summarizes the experiences associated with the cleanup and radiological stabilization of the 100-B, -C, -D, and -DR spent fuel pools, and discusses a number of lessons learned items

  5. Radiation dose rates from commercial PWR and BWR spent fuel elements

    International Nuclear Information System (INIS)

    Willingham, C.E.

    1981-10-01

    Data on measurements of gamma dose rates from commercial reactor spent fuel were collected, and documented calculated gamma dose rates were reviewed. As part of this study, the gamma dose rate from spent fuel was estimated, using computational techniques similar to previous investigations into this problem. Comparison of the measured and calculated dose rates provided a recommended dose rate in air versus distance curve for PWR spent fuel

  6. Final disposal of spent fuel in the Finnish bedrock

    International Nuclear Information System (INIS)

    1992-12-01

    Teollisuuden Voima Oy (TVO) is preparing for the final disposal of spent nuclear fuel from the Olkiluoto nuclear power plant (TVO-I and TVO-II reactors). According to present estimates, a total of 1840 tU of spent fuel will be accumulated during the 40-year lifetime of the power plant. An interim storage facility for spent fuel (TVO-KPA Store) has operated at Olkiluoto since 1987. The spent fuel will be held in storage for several decades before it is shipped to the repository site. Both train and road transportation are possible. The spent fuel will be encapsulated in composite copper and steel canisters (ACP Canister) in a facility that will be build above the ground on the site where the repository is located. The repository will be constructed at the depth of several hundreds of meters in the bedrock. In 1987 five areas were selected for preliminary site investigations. The safety analysis (TVO-92) that was carried out shows that the proposed safety criteria would be met at each of the candidate sites. In future expected conditions there would never be significant releases of radioactive substances to the biosphere. The site investigations will be continued in the period 1993 to 2000. In parallel, a R and D programme will be devoted to the safety and technology of final disposal. The site for final disposal will be selected in the year 2000 with the aim of having the capability to start the disposal operations in 2020

  7. NRC analysis of the environmental impacts and licensing policies for expanded spent fuel storage in the United States

    International Nuclear Information System (INIS)

    Smith, C.V. Jr.

    1978-01-01

    This paper reviews the findings of the U.S. environmental impact studies on spent fuel storage to the year 2000, addresses design criteria for independent spent fuel storage installations and expresses the position of the NRC for licensing expanded spent fuel storage capabilities until such time as final solutions are established

  8. NRC Analysis of the environmental impacts and licensing policies for expanded spent fuel storage in the United States

    International Nuclear Information System (INIS)

    Clifford, V.S.

    1978-01-01

    The findings of the U.S. environmental impact studies on spent fuel storage to the year 2000 are reviewed, the design criteria for independent spent fuel storage installations are addressed and the position of the NRC for licensing expanded spent fuel storage capabilities, until such time as final solutions are established, is expressed. (author)

  9. Mechanical and thermomechanical calculations related to the storage of spent nuclear-fuel assemblies in granite

    International Nuclear Information System (INIS)

    Butkovich, T.R.

    1980-05-01

    A generic test of the geologic storage of spent-fuel assemblies is being made at Nevada Test Site. The spent-fuel assemblies were emplaced at a depth of 420 m (1370 ft) below the surface in a typical granite and will be retrieved at a later time. The early time, close-in thermal history of this type of repository is being simulated with spent-fuel and electrically heated canisters in a central drift, with auxiliary heaters in two parallel side drifts. Prior to emplacement of the spent-fuel canisters, preliminary calculations were made using a pair of existing finite-element codes, ADINA and ADINAT

  10. AN INVESTIGATION OF TIME LAG MAPS USING THREE-DIMENSIONAL SIMULATIONS OF HIGHLY STRATIFIED HEATING

    Energy Technology Data Exchange (ETDEWEB)

    Winebarger, Amy R. [NASA Marshall Space Flight Center, ZP 13, Huntsville, AL 35812 (United States); Lionello, Roberto; Downs, Cooper; Mikić, Zoran; Linker, Jon [Predictive Science, Inc., 9990 Mesa Rim Rd., Ste. 170, San Diego, CA 92121-2910 (United States); Mok, Yung, E-mail: amy.r.winebarger@nasa.gov, E-mail: lionel@predsci.com, E-mail: cdowns@predsci.com, E-mail: mikicz@predsci.com, E-mail: linkerj@predsci.com, E-mail: ymok@uci.edu [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States)

    2016-11-10

    The location and frequency of coronal energy release provide a significant constraint on the coronal heating mechanism. The evolution of the intensity observed in coronal structures found from time lag analysis of Atmospheric Imaging Assembly (AIA) data has been used to argue that heating must occur sporadically. Recently, we have demonstrated that quasi-steady, highly stratified (footpoint) heating can produce results qualitatively consistent with the evolution of observed coronal structures. The goals of this paper are to demonstrate that time lag analysis of 3D simulations of footpoint heating are qualitatively consistent with time lag analysis of observations and to use the 3D simulations to further understand whether time lag analysis is a useful tool in defining the evolution of coronal structures. We find the time lag maps generated from simulated data are consistent with the observed time lag maps. We next investigate several example points. In some cases, the calculated time lag reflects the evolution of a unique loop along the line of sight, though there may be additional evolving structures along the line of sight. We confirm that using the multi-peak AIA channels can produce time lags that are difficult to interpret. We suggest using a different high temperature channel, such as an X-ray channel. Finally, we find that multiple evolving structures along the line of sight can produce time lags that do not represent the physical properties of any structure along the line of sight, although the cross-correlation coefficient of the lightcurves is high. Considering the projected geometry of the loops may reduce some of the line-of-sight confusion.

  11. Investigations into near-real-time surveying for geophysical data collection using an autonomous ground vehicle

    Science.gov (United States)

    Phelps, Geoffrey A.; Ippolito, C.; Lee, R.; Spritzer, R.; Yeh, Y.

    2014-01-01

    The U.S. Geological Survey and the National Aeronautics and Space Administration are cooperatively investigating the utility of unmanned vehicles for near-real-time autonomous surveys of geophysical data collection. Initially focused on unmanned ground vehicle collection of magnetic data, this cooperative effort has brought unmanned surveying, precision guidance, near-real-time communication, on-the-fly data processing, and near-real-time data interpretation into the realm of ground geophysical surveying, all of which offer advantages over current methods of manned collection of ground magnetic data. An unmanned ground vehicle mission has demonstrated that these vehicles can successfully complete missions to collect geophysical data, and add advantages in data collection, processing, and interpretation. We view the current experiment as an initial phase in further unmanned vehicle data-collection missions, including aerial surveying.

  12. Investigations of timing during the schedule and reinforcement intervals with wheel-running reinforcement.

    Science.gov (United States)

    Belke, Terry W; Christie-Fougere, Melissa M

    2006-11-01

    Across two experiments, a peak procedure was used to assess the timing of the onset and offset of an opportunity to run as a reinforcer. The first experiment investigated the effect of reinforcer duration on temporal discrimination of the onset of the reinforcement interval. Three male Wistar rats were exposed to fixed-interval (FI) 30-s schedules of wheel-running reinforcement and the duration of the opportunity to run was varied across values of 15, 30, and 60s. Each session consisted of 50 reinforcers and 10 probe trials. Results showed that as reinforcer duration increased, the percentage of postreinforcement pauses longer than the 30-s schedule interval increased. On probe trials, peak response rates occurred near the time of reinforcer delivery and peak times varied with reinforcer duration. In a second experiment, seven female Long-Evans rats were exposed to FI 30-s schedules leading to 30-s opportunities to run. Timing of the onset and offset of the reinforcement period was assessed by probe trials during the schedule interval and during the reinforcement interval in separate conditions. The results provided evidence of timing of the onset, but not the offset of the wheel-running reinforcement period. Further research is required to assess if timing occurs during a wheel-running reinforcement period.

  13. Near surface spent fuel storage: environmental issues

    International Nuclear Information System (INIS)

    Nelson, I.C.; Shipler, D.B.; McKee, R.W.; Glenn, R.D.

    1979-01-01

    Interim storage of spent fuel appears inevitable because of the lack of reprocessing plants and spent fuel repositories. This paper examines the environmental issues potentially associated with management of spent fuel before disposal or reprocessing in a reference scenario. The radiological impacts of spent fuel storage are limited to low-level releases of noble gases and iodine. Water needed for water basin storage of spent fuel and transportation accidents are considered; the need to minimize the distance travelled is pointed out. Resource commitments for construction of the storage facilities are analyzed

  14. Overview of spent fuel management and problems

    International Nuclear Information System (INIS)

    Ritchie, I.G.; Ernst, P.C.

    1998-01-01

    Results compiled in the research reactor spent fuel database are used to assess the status of research reactor spent fuel worldwide. Fuel assemblies, their types, enrichment, origin of enrichment and geological distribution among the industrialized and developed countries of the world are discussed. Fuel management practices in wet and dry storage facilities and the concerns of reactor operators about long-term storage of their spent fuel are presented and some of the activities carried out by the International Atomic Energy Agency to address the issues associated with research reactor spent fuel are outlined. Some projections of spent fuel inventories to the year 2006 are presented and discussed. (author)

  15. Dealing with the current permissibility application for constructing a spent fuel DGR in Sweden. SKB's license applications for a spent fuel repository

    International Nuclear Information System (INIS)

    Olsson, Olle

    2014-01-01

    The nuclear power utilities in Sweden were in 1976 obliged to demonstrate a safe method for final disposal of spent fuel in order to start operation of new reactors. This initiated a comprehensive research, development and demonstration programme and the development of the KBS-method for final disposal. A new Nuclear Activities Act in 1984 gave the reactor owners full technical and financial responsibility for the waste. They gave in turn SKB the responsibility for all nuclear waste management. Reprocessing was no longer required and direct disposal of the spent fuel has, since then, been the main alternative. Alternative methods for final disposal have been evaluated and compared to the KBS-3-method but it has remained the preferred alternative. A comprehensive research, development and demonstration programme to strengthen the scientific basis and to refine the KBS-3-method has been operated by SKB since then. The site selection process for the final repository for spent nuclear fuel was initiated in 1992. The work included general siting studies at the national and the municipal level and in 2002, SKB initiated site investigations for siting of a final repository on two sites: the Simpevarp and Laxemar areas and the Forsmark area. At the same time, the work on preparing license applications to construct and operate an encapsulation plant and a final repository for spent fuel was started. In June 2009, SKB announced Forsmark as the selected site for the final repository. This paper reviews the applicable legislation and describes the license application, the licensing review and the preparations for implementation

  16. Nuclear Forensics Attributing the Source of Spent Fuel Used in an RDD Event

    International Nuclear Information System (INIS)

    Scott, M.R.

    2005-01-01

    An RDD attack against the U.S. is something America needs to prepare against. If such an event occurs the ability to quickly identify the source of the radiological material used in an RDD would aid investigators in identifying the perpetrators. Spent fuel is one of the most dangerous possible radiological sources for an RDD. In this work, a forensics methodology was developed and implemented to attribute spent fuel to a source reactor. The specific attributes determined are the spent fuel burnup, age from discharge, reactor type, and initial fuel enrichment. It is shown that by analyzing the post-event material, these attributes can be determined with enough accuracy to be useful for investigators. The burnup can be found within a 5% accuracy, enrichment with a 2% accuracy, and age with a 10% accuracy. Reactor type can be determined if specific nuclides are measured. The methodology developed was implemented into a code call NEMASYS. NEMASYS is easy to use and it takes a minimum amount of time to learn its basic functions. It will process data within a few minutes and provide detailed information about the results and conclusions

  17. Nuclear Forensics Attributing the Source of Spent Fuel Used in an RDD Event

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Mark Robert [Texas A & M Univ., College Station, TX (United States)

    2005-05-01

    An RDD attack against the U.S. is something America needs to prepare against. If such an event occurs the ability to quickly identify the source of the radiological material used in an RDD would aid investigators in identifying the perpetrators. Spent fuel is one of the most dangerous possible radiological sources for an RDD. In this work, a forensics methodology was developed and implemented to attribute spent fuel to a source reactor. The specific attributes determined are the spent fuel burnup, age from discharge, reactor type, and initial fuel enrichment. It is shown that by analyzing the post-event material, these attributes can be determined with enough accuracy to be useful for investigators. The burnup can be found within a 5% accuracy, enrichment with a 2% accuracy, and age with a 10% accuracy. Reactor type can be determined if specific nuclides are measured. The methodology developed was implemented into a code call NEMASYS. NEMASYS is easy to use and it takes a minimum amount of time to learn its basic functions. It will process data within a few minutes and provide detailed information about the results and conclusions.

  18. Probability of spent fuel transportation accidents

    International Nuclear Information System (INIS)

    McClure, J.D.

    1981-07-01

    The transported volume of spent fuel, incident/accident experience and accident environment probabilities were reviewed in order to provide an estimate of spent fuel accident probabilities. In particular, the accident review assessed the accident experience for large casks of the type that could transport spent (irradiated) nuclear fuel. This review determined that since 1971, the beginning of official US Department of Transportation record keeping for accidents/incidents, there has been one spent fuel transportation accident. This information, coupled with estimated annual shipping volumes for spent fuel, indicated an estimated annual probability of a spent fuel transport accident of 5 x 10 -7 spent fuel accidents per mile. This is consistent with ordinary truck accident rates. A comparison of accident environments and regulatory test environments suggests that the probability of truck accidents exceeding regulatory test for impact is approximately 10 -9 /mile

  19. Application of spent fuel treatment technology to plutonium immobilization

    International Nuclear Information System (INIS)

    McPheeters, C.C.; Ackerman, J.P.; Gay, E.C., Johnson, G.K.

    1996-01-01

    The purpose of the electrometallurgical treatment technology being developed at Argonne National Laboratory (ANL) is to convert certain spent nuclear fuels into waste forms that are suitable for disposal in a geological repository for nuclear waste. The spent fuels of interest are those that cannot be safely stored for a long time in their current condition, and those that cannot be qualified for repository disposal. This paper explores the possibility of applying this electrometallurgical treatment technology to immobilization of surplus fissile materials, primarily plutonium. Immobilization of surplus fissile materials by electrometallurgical treatment could be done in the same facilities, at the same time. and in the same equipment as the proposed treatment of the present inventory of spent nuclear fuel. The cost and schedule savings of this simultaneous treatment scheme would be significant

  20. Investigation of Time Series Representations and Similarity Measures for Structural Damage Pattern Recognition

    Directory of Open Access Journals (Sweden)

    Wenjia Liu

    2013-01-01

    Full Text Available This paper investigates the time series representation methods and similarity measures for sensor data feature extraction and structural damage pattern recognition. Both model-based time series representation and dimensionality reduction methods are studied to compare the effectiveness of feature extraction for damage pattern recognition. The evaluation of feature extraction methods is performed by examining the separation of feature vectors among different damage patterns and the pattern recognition success rate. In addition, the impact of similarity measures on the pattern recognition success rate and the metrics for damage localization are also investigated. The test data used in this study are from the System Identification to Monitor Civil Engineering Structures (SIMCES Z24 Bridge damage detection tests, a rigorous instrumentation campaign that recorded the dynamic performance of a concrete box-girder bridge under progressively increasing damage scenarios. A number of progressive damage test case datasets and damage test data with different damage modalities are used. The simulation results show that both time series representation methods and similarity measures have significant impact on the pattern recognition success rate.

  1. Creation of free excitons in solid krypton investigated by time-resolved luminescence spectroscopy

    International Nuclear Information System (INIS)

    Kisand, Vambola; Kirm, Marco; Negodin, Evgeni; Sombrowski, Elke; Steeg, Barbara; Vielhauer, Sebastian; Zimmerer, Georg

    2003-01-01

    The creation and relaxation of secondary excitons in solid Kr was investigated using energy-and time-resolved luminescence spectroscopy in the vacuum ultraviolet region. The spectrally selected emission of the free exciton (FE) was used as a probe for an investigation of the different exciton creation processes. Delayed FE creation via electron-hole recombination and 'prompt' (in terms of the time-resolution of the experiment) creation of excitons were separated. The 'prompt' creation of a FE appears in the region above threshold energy E th , which is equal to the sum of the band gap energy and the free exciton energy. 'Prompt' creation of excitons above E th is ascribed to a superposition of two processes: (i) creation of the electronic polaron complex (one-step process) and (ii) inelastic scattering of photoelectrons described in the framework of the multiple-parabolic-branch band model (two-step process). In addition, the ratio spectrum of the time-integrated FE and self-trapped exciton (STE) emission was analysed. The behaviour of the ratio spectrum is a proof that electron-hole recombination leads to STE states through FE states as precursors

  2. Investigation of Time Series Representations and Similarity Measures for Structural Damage Pattern Recognition

    Science.gov (United States)

    Swartz, R. Andrew

    2013-01-01

    This paper investigates the time series representation methods and similarity measures for sensor data feature extraction and structural damage pattern recognition. Both model-based time series representation and dimensionality reduction methods are studied to compare the effectiveness of feature extraction for damage pattern recognition. The evaluation of feature extraction methods is performed by examining the separation of feature vectors among different damage patterns and the pattern recognition success rate. In addition, the impact of similarity measures on the pattern recognition success rate and the metrics for damage localization are also investigated. The test data used in this study are from the System Identification to Monitor Civil Engineering Structures (SIMCES) Z24 Bridge damage detection tests, a rigorous instrumentation campaign that recorded the dynamic performance of a concrete box-girder bridge under progressively increasing damage scenarios. A number of progressive damage test case datasets and damage test data with different damage modalities are used. The simulation results show that both time series representation methods and similarity measures have significant impact on the pattern recognition success rate. PMID:24191136

  3. Investigation of individuals going to coffeehouse with the aim of leisure time activities

    Directory of Open Access Journals (Sweden)

    Hüseyin ÖZTÜRK

    2015-08-01

    Full Text Available The main basis of this research is to investigate pe ople going to coffeehouse with the aim of leisure time activities. The research group of this study consist of individuals going to the coffeehouses with the aim of leisure time activities in the city of Gaz iantep, Turkey. A total of 421 individuals joined to the research voluntarily. The Research consists of two parts. In the first part, personal information was used. In the second part, the leisure questionnaire form developed by Binarbaşı (2006 was u sed in order to determine individuals’ leisure time habits. The statistical programme SPSS 16.0 software packed programme was used to analyze the data. While analyzing the data, descriptive statistics methods were used as frequency percentage so P <0.05 was considered statistically significant. As the result of research; it is seen that 41 years of age and older people prefer going to coffehouses more than the others, the big majority of them are elementary and junior high school graduates and mostly they are married people, mostly they have 1 - 2 children, as a profession they are mostly workers who take minimum wage and they work very little over salary as monthly income. People going to the coffeehouses in their free time preffered at a high rate that they mostly go to the coffeehouses to spend time with their friends, they are happy with this activity, in the same time they find it very relaxing and they mostly watch TV when they don’t go to coffeehouses in their spare time and they in dicated the reason for failure to participate in other activities except coffeehouses as the absence of relevant activities and programmes appealing to them and economic handicap.

  4. Possible application of brewer’s spent grain in biotechnology

    Directory of Open Access Journals (Sweden)

    Pejin Jelena D.

    2013-01-01

    Full Text Available Brewer’s spent grain is the major by-product in beer production. It is produced in large quantities (20 kg per 100 liters of produced beer throughout the year at a low cost or no cost, and due to its high protein and carbohydrates content it can be used as a raw material in biotechnology. Biotechnological processes based on renewable agro-industrial by-products have ecological (zero CO2 emission, eco-friendly by-products and economical (cheap raw materials and reduction of storage costs advantages. The use of brewer’s spent grain is still limited, being basically used as animal feed. Researchers are trying to improve the application of brewer’s spent grain by finding alternative uses apart from the current general use as an animal feed. Its possible applications are in human nutrition, as a raw material in biotechnology, energy production, charcoal production, paper manufacture, as a brick component, and adsorbent. In biotechnology brewer’s spent grain could be used as a substrate for cultivation of microorganisms and enzyme production, additive of yeast carrier in beer fermentation, raw material in production of lactic acid, bioethanol, biogas, phenolic acids, xylitol, and pullulan. Some possible applications for brewer’s spent grain are described in this article including pre-treatment conditions (different procedures for polysaccharides, hemicelluloses, and cellulose hydrolysis, working microorganisms, fermentation parameters and obtained yields. The chemical composition of brewer’s spent grain varies according to barley variety, harvesting time, malting and mashing conditions, and a quality and type of unmalted raw material used in beer production. Brewer’s spent grain is lignocellulosic material rich in protein and fibre, which account for approximately 20 and 70% of its composition, respectively.

  5. Storage of spent fuel from power reactors. 2003 conference proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-10-01

    An International Conference on Storage of Spent Fuel from Power Reactors was organized by the IAEA in co-operation with the OECD Nuclear Energy Agency. The conference gave an opportunity to exchange information on the state of the art and prospects of spent fuel storage, to discuss the worldwide situation and the major factors influencing the national policies in this field and to identify the most important directions that national efforts and international co-operation in this area should take. The conference confirmed that the primary spent fuel management solution for the next decades will be interim storage. While the next step can be reprocessing or disposal, all spent fuel or high level waste from reprocessing must sooner or later be disposed of. The duration of interim storage is now expected to be much longer than earlier projections (up to 100 years and beyond). The storage facilities will have to be designed for these longer storage times and also for receiving spent fuel from advanced fuel cycle practices (i.e. high burnup and MOX spent fuel). It was noted that the handling and storage of spent fuel is a mature technology and meets the stringent safety requirements applicable in the different countries. The changes in nuclear policy and philosophy across the world, and practical considerations, have made storage a real necessity in the nuclear power industry. Utilities, vendors and regulators alike are addressing this adequately. The IAEA wishes to express appreciation to all chairs and co-chairs as well as all authors for their presentations to the conference and papers included in these proceedings.

  6. Storage of spent fuel from power reactors. 2003 conference proceedings

    International Nuclear Information System (INIS)

    2003-01-01

    An International Conference on Storage of Spent Fuel from Power Reactors was organized by the IAEA in co-operation with the OECD Nuclear Energy Agency. The conference gave an opportunity to exchange information on the state of the art and prospects of spent fuel storage, to discuss the worldwide situation and the major factors influencing the national policies in this field and to identify the most important directions that national efforts and international co-operation in this area should take. The conference confirmed that the primary spent fuel management solution for the next decades will be interim storage. While the next step can be reprocessing or disposal, all spent fuel or high level waste from reprocessing must sooner or later be disposed of. The duration of interim storage is now expected to be much longer than earlier projections (up to 100 years and beyond). The storage facilities will have to be designed for these longer storage times and also for receiving spent fuel from advanced fuel cycle practices (i.e. high burnup and MOX spent fuel). It was noted that the handling and storage of spent fuel is a mature technology and meets the stringent safety requirements applicable in the different countries. The changes in nuclear policy and philosophy across the world, and practical considerations, have made storage a real necessity in the nuclear power industry. Utilities, vendors and regulators alike are addressing this adequately. The IAEA wishes to express appreciation to all chairs and co-chairs as well as all authors for their presentations to the conference and papers included in these proceedings

  7. HTGR spent fuel storage study

    International Nuclear Information System (INIS)

    Burgoyne, R.M.; Holder, N.D.

    1979-04-01

    This report documents a study of alternate methods of storing high-temperature gas-cooled reactor (HTGR) spent fuel. General requirements and design considerations are defined for a storage facility integral to a fuel recycle plant. Requirements for stand-alone storage are briefly considered. Three alternate water-cooled storage conceptual designs (plug well, portable well, and monolith) are considered and compared to a previous air-cooled design. A concept using portable storage wells in racks appears to be the most favorable, subject to seismic analysis and economic evaluation verification

  8. Spent nuclear fuel sampling strategy

    International Nuclear Information System (INIS)

    Bergmann, D.W.

    1995-01-01

    This report proposes a strategy for sampling the spent nuclear fuel (SNF) stored in the 105-K Basins (105-K East and 105-K West). This strategy will support decisions concerning the path forward SNF disposition efforts in the following areas: (1) SNF isolation activities such as repackaging/overpacking to a newly constructed staging facility; (2) conditioning processes for fuel stabilization; and (3) interim storage options. This strategy was developed without following the Data Quality Objective (DQO) methodology. It is, however, intended to augment the SNF project DQOS. The SNF sampling is derived by evaluating the current storage condition of the SNF and the factors that effected SNF corrosion/degradation

  9. Dry storage of spent fuel

    International Nuclear Information System (INIS)

    Jeffrey, R.

    1993-01-01

    Scottish Nuclear's plans to build and operate dry storage facilities at each of its two nuclear power station sites in Scotland are explained. An outline of where waste materials arise as part of the operation and decommissioning of nuclear power stations, the volumes for each category of high-, intermediate-and low-level wastes and the costs involved are given. The present procedure for the spent fuels from Hunterston-B and Torness stations is described and Scottish Nuclear's aims of driving output up and costs down are studied. (UK)

  10. Spent fuel canister docking station

    International Nuclear Information System (INIS)

    Suikki, M.

    2006-01-01

    The working report for the spent fuel canister docking station presents a design for the operation and structure of the docking equipment located in the fuel handling cell for the spent fuel in the encapsulation plant. The report contains a description of the basic requirements for the docking station equipment and their implementation, the operation of the equipment, maintenance and a cost estimate. In the designing of the equipment all the problems related with the operation have been solved at the level of principle, nevertheless, detailed designing and the selection of final components have not yet been carried out. In case of defects and failures, solutions have been considered for postulated problems, and furthermore, the entire equipment was gone through by the means of systematic risk analysis (PFMEA). During the docking station designing we came across with needs to influence the structure of the actual disposal canister for spent nuclear fuel, too. Proposed changes for the structure of the steel lid fastening screw were included in the report. The report also contains a description of installation with the fuel handling cell structures. The purpose of the docking station for the fuel handling cell is to position and to seal the disposal canister for spent nuclear fuel into a penetration located on the cell floor and to provide suitable means for executing the loading of the disposal canister and the changing of atmosphere. The designed docking station consists of a docking ring, a covering hatch, a protective cone and an atmosphere-changing cap as well as the vacuum technology pertaining to the changing of atmosphere and the inert gas system. As far as the solutions are concerned, we have arrived at rather simple structures and most of the actuators of the system are situated outside of the actual fuel handling cell. When necessary, the equipment can also be used for the dismantling of a faulty disposal canister, cut from its upper end by machining. The

  11. Spent fuel storage requirements 1987

    International Nuclear Information System (INIS)

    1987-09-01

    Historical inventories of spent fuel and utility estimates of future discharges from US commercial nuclear reactors are presented through the year 2005. The ultimate needs for additional storage capacity are estimated. These estimtes are based on the maximum capacities within current and planned at-reactor facilities and on any planned transshipments of fuel to other reactors or facilities. Historical data through December, 1986, and projected discharges through the end of reactor life are used in this analysis. The source data was supplied by the utilities to the DOE Energy Information Administration (EIA) through the 1987 RW-859 data survey. 14 refs., 4 figs., 9 tabs

  12. A Qualitative Analysis of the Neutron Population in Fresh and Spent Fuel Assemblies during Simulated Interrogation using the Differential Die-Away Technique

    International Nuclear Information System (INIS)

    Lundkvista, Niklas; Goodsell, Alison V.; Grapea, Sophie; Hendricksb, John S.; Henzlb, Vladimir; Swinhoe, Martyn T.; Tobin, Stephen J.

    2015-01-01

    Monte Carlo simulations were performed for the differential die-away (DDA) technique to analyse the time-dependent behaviour of the neutron population in fresh and spent nuclear fuel assemblies as part of the Next Generation Safeguards Initiative Spent Fuel (NGSI-SF) Project. Simulations were performed to investigate both a possibly portable as well as a permanent DDA instrument. Taking advantage of a custom made modification to the MCNPX code, the variation in the neutron population, simultaneously in time and space, was examined. The motivation for this research was to improve the design of the DDA instrument, as it is being considered for possible deployment at the Central Storage of Spent Nuclear Fuel and Encapsulation Plant in Sweden (Clab), as well as to assist in the interpretation of the both simulated and measured signals.

  13. Status of the spent fuel dry storage programme for Cernavoda NPP

    International Nuclear Information System (INIS)

    Radu, M.

    1999-01-01

    The Cernavoda NPP Unit 1 (600 MWe Standard type) is in operation since December 1996. Within the framework of the R and D Radioactive Waste and Spent Fuel Management Programme, investigations, studies and research are carried out on site identification and conceptual designs for both a Spent Fuel Interim Storage Facility and a Spent Fuel Disposal Facility. The status of the work performed in the framework of this programme as well as the situation of the spent fuel resulting from the Research Institutes will be presented in the paper. (author)

  14. Neutron time-of-flight techniques for investigation of the extinction effect

    International Nuclear Information System (INIS)

    Niimura, N.; Tomiyoshi, S.; Takahashi, J.; Harada, J.

    1975-01-01

    An application of the time-of-flight neutron diffraction technique to an investigation of the nature of the extinction effect in a single-crystal specimen is given. It is shown that the wavelength dependence of the extinction can be easily obtained by changing the scattering angle. An estimation of the extinction factor for a CuCl single crystal is given as an example and a comparison of the results with recent extinction theory [Becker and Coppens. Acta Cryst.(1974). A30, 129-147; 148-153] is made. (Auth.)

  15. Argonne's Expedited Site Characterization: An integrated approach to cost- and time-effective remedial investigation

    International Nuclear Information System (INIS)

    Burton, J.C.; Walker, J.L.; Aggarwal, P.K.; Meyer, W.T.

    1995-01-01

    Argonne National Laboratory has developed a methodology for remedial site investigation that has proven to be both technically superior to and more cost- and time-effective than traditional methods. This methodology is referred to as the Argonne Expedited Site Characterization (ESC). Quality is the driving force within the process. The Argonne ESC process is abbreviated only in time and cost and never in terms of quality. More usable data are produced with the Argonne ESC process than with traditional site characterization methods that are based on statistical-grid sampling and multiple monitoring wells. This paper given an overview of the Argonne ESC process and compares it with traditional methods for site characterization. Two examples of implementation of the Argonne ESC process are discussed to illustrate the effectiveness of the process in CERCLA (Comprehensive Environmental Response, Compensation, and Liability Act) and RCRA (Resource Conservation and Recovery Act) programs

  16. Thermal-hydraulic analysis of spent fuel storage systems

    International Nuclear Information System (INIS)

    Rector, D.R.; Wheeler, C.L.; Lombardo, N.J.

    1987-01-01

    This paper describes the COBRA-SFS (Spent Fuel Storage) computer code, which is designed to predict flow and temperature distributions in spent nuclear fuel storage and transportation systems. The decay heat generated by spent fuel in a dry storage cask is removed through a combination of conduction, natural convection, and thermal radiation. One major advantage of COBRA-SFS is that fluid recirculation within the cask is computed directly by solving the mass and momentum conservation equations. In addition, thermal radiation heat transfer is modeled using detailed radiation exchange factors based on quarter-rod segments. The equations governing mass, momentum, and energy conservation for incompressible flows are presented, and the semi-implicit solution method is described. COBRA-SFS predictions are compared to temperature data from a spent fuel storage cask test and the effect of different fill media on the cladding temperature distribution is discussed. The effect of spent fuel consolidation on cask thermal performance is also investigated. 16 refs., 6 figs., 2 tabs

  17. A scheme of better utilization of PWR spent fuels

    International Nuclear Information System (INIS)

    Chung, Bum Jin; Kang, Chang Soon

    1991-01-01

    The recycle of PWR spent fuels in a CANDU reactor, so called the tandem fuel cycle is investigated in this study. This scheme of utilizing PWR spent fuels will ease the shortage of spent fuel storage capacity as well as will improve the use of uranium resources. The minimum modification the design of present CANDU reactor is seeked in the recycle. Nine different fuel types are considered in this work and are classified into two categories: refabrication and reconfiguration. For refabrication, PWR spent fuels are processed and refabricated into the present 37 rod lattice structure of fuel bundle, and for reconfiguration, meanwhile, spent fuels are simply disassembled and rods are cut to fit into the present grid configuration of fuel bundle without refabrication. For each fuel option, the neutronics calculation of lattice was conducted to evaluate the allowable burn up and distribution. The fuel cycle cost of each option was also computed to assess the economic justification. The results show that most tandem fuel cycle option considered in this study are technically feasible as well as economically viable. (Author)

  18. Reprocessing of spent nuclear fuel; Prerada isluzenog nuklearnog goriva

    Energy Technology Data Exchange (ETDEWEB)

    Gal, I [Institute of Nuclear Sciences Boris Kidric, Laboratorija za visoku aktivnost, Vinca, Beograd (Serbia and Montenegro)

    1963-12-15

    This report covers: chemical-technology investigation of modified purex process for reprocessing of spent fuel; implementation of the procedure for obtaining plutonium peroxide and oxalate; research in the field of uranium, plutonium, and fission products separation by inorganic ion exchangers and extraction by organic solutions; study of the fission products in the heavy water RA reactor.

  19. Bioremediation of soil contaminated by spent diesel oil using ...

    African Journals Online (AJOL)

    Objectives: To investigate the potential of Pleurotus pulmonarius in the bioremediation of soil contaminated with spent diesel oil at 5, 10 and 15% (v/w) level of contamination over a period of one and two months of incubation. Methodology and results: A pure culture of P. pulmonarius was obtained from the Plant physiology ...

  20. Growth response of Ricinus communis L (castor oil) in spent ...

    African Journals Online (AJOL)

    The growth response of castor oil plant, Ricinus communis, in spent lubricating oil (SLO) was investigated using 1-6% w/w SLO and a control. The result showed that highest percent germination of approximately 92, was obtained in control and the least in 5% w/w. The early germination obtained in this study was significant ...

  1. An Indian perspective for transportation and storage of spent fuel

    International Nuclear Information System (INIS)

    Dey, P.K.

    2005-01-01

    The spent fuel discharged from the reactors are temporarily stored at the reactor pool. After a certain cooling time, the spent fuel is moved to the storage locations either on or off reactor site depending on the spent fuel management strategy. As India has opted for a closed fuel cycle for its nuclear energy development, reprocessing of the spent fuel, recycling of the reprocessed plutonium and uranium and disposal of the wastes from the reprocessing operations forms the spent fuel management strategy. Since the reprocessing operations are planned to match the nuclear energy programme, storage of the spent fuel in ponds are adopted prior to reprocessing. Transport of the spent fuel to the storage locations are carried out adhering to international and national guide lines. India is having 14 operating power reactors and three research reactors. The spent fuel from the two safeguarded BWRs are stored at-reactor (AR) storage pond. A separate wet storage facility away-from-reactor (AFR) has been designed, constructed and made operational since 1991 for additional fuel storage. Storage facilities are provided in ARs at other reactor locations to cater to 10 reactor-years of operation. A much lower capacity spent fuel storage is provided in reprocessing plants on the same lines of AR fuel storage design. Since the reprocessing operations are carried out on a need basis, to cater to the increased storage needs two new spent fuel storage facilities (SFSF) are being designed and constructed near the existing nuclear plant sites. India has mastered the technology for design, construction and operation of wet spent fuel storage facility meeting all the international standards Wet storage of the spent fuel is the most commonly adopted mode all over the world. Recently an alternate mode viz. dry storage has also been considered. India has designed, constructed and operated lead shielded dry storage casks and is operational at one site. A dry storage cask made of concrete

  2. Electrochemical treatment of spent tan bath solution for reuse

    Directory of Open Access Journals (Sweden)

    Amel Benhadji

    2018-03-01

    Full Text Available A spent tanning bath contains high concentration of salts, chromium and protein. The treatment system for removal of chlorides or chromium from this effluent is expensive. In this context this waste has to be reused. Our study focuses on the application of advanced oxidation processes for protein removal present in a tanning bath. To improve the quality of the chromium tanning bath, two electrochemical processes (electrooxidation and peroxi-electrocoagulation process, PEP are investigated in a batch reactor. The effects of operational parameters such as reactor configuration, current density and electrolysis time on chemical oxygen demand (COD and protein removal efficiency are examined. Results indicated that under the optimum operating range for process, the COD and protein removal efficiency reached 53 and 100%, respectively. The optimum values are determined for the hybrid process (PEP under 0.13 A·cm−2 over 2 h. The treated tanning bath is used as a tanning solution in leather processing. The influence of chromium salt dose, pH solution, stirring time and contact time on the leather characteristic is evaluated. The hides tanned after the addition of 0.25% of commercial chromium salt, at pH solution, leaving them stirring for 4 h with a contact time of 2 days, and showed good hydrothermal stability and physical characteristics of leather.

  3. Spent fuel and high-level radioactive waste storage

    International Nuclear Information System (INIS)

    Trigerman, S.

    1988-06-01

    The subject of spent fuel and high-level radioactive waste storage, is bibliographically reviewed. The review shows that in the majority of the countries, spent fuels and high-level radioactive wastes are planned to be stored for tens of years. Sites for final disposal of high-level radioactive wastes have not yet been found. A first final disposal facility is expected to come into operation in the United States of America by the year 2010. Other final disposal facilities are expected to come into operation in Germany, Sweden, Switzerland and Japan by the year 2020. Meanwhile , stress is placed upon the 'dry storage' method which is carried out successfully in a number of countries (Britain and France). In the United States of America spent fuels are stored in water pools while the 'dry storage' method is still being investigated. (Author)

  4. The effects of prior knowledge on study-time allocation and free recall: investigating the discrepancy reduction model.

    Science.gov (United States)

    Verkoeijen, Peter P J L; Rikers, Remy M J P; Schmidt, Henk G

    2005-01-01

    In this study, the authors examined the influence of prior knowledge activation on information processing by means of a prior knowledge activation procedure adopted from the read-generate paradigm. On the basis of cue-target pairs, participants in the experimental groups generated two different sets of items before studying a relevant list. Subsequently, participants were informed that they had to study the items in the list and that they should try to remember as many items as possible. The authors assessed the processing time allocated to the items in the list and free recall of those items. The results revealed that the experimental groups spent less time on items that had already been activated. In addition, the experimental groups outperformed the control group in overall free recall and in free recall of the activated items. Between-group comparisons did not demonstrate significant effects with respect to the processing time and free recall of nonactivated items. The authors interpreted these results in terms of the discrepancy reduction model of regulating the amount of processing time allocated to different parts of the list.

  5. Sealed can of spent fuel

    International Nuclear Information System (INIS)

    Suzuki, Yasuyuki.

    1976-01-01

    Object: To provide a seal plug cover with a gripping portion fitted to a canning machine and a gripping portion fitted to a gripper of the same configuration as a fuel body for handling the fuel body so as to facilitate the handling work. Structure: A sealed can comprises a vessel and a seal plug cover, said cover being substantially in the form of a bottomed cylinder, which is slipped on the vessel and air-tightly secured by a fastening bolt between it and a flange. The spent fuel body is received into the vessel together with coolant during the step of canning operation. Said seal plug cover has two gripping portions, one for opening and closing the plug cover of the canning machine as an exclusive use member, the other being in the form of a hook-shaped peripheral groove, whereby the gripping portions may be effectively used using the same gripper when the spent fuel body is transported while being received in the sealed can or when the fuel body is removed from the sealed can. (Kawakami, Y.)

  6. Spent fuel storage criticality safety

    Energy Technology Data Exchange (ETDEWEB)

    Amin, E M; Elmessiry, A M [National center of nuclear safety and radiation control atomic energy authority, (Egypt)

    1995-10-01

    The safety aspects of the spent fuel storage pool of the Egyptian test and research reactor one (ET-R R-1) has to be assessed as part of a general overall safety evaluation to be included in a safety analysis report (SAR) for this reactor. The present work treats the criticality safety of the spent fuel storage pool. Conservative calculations based on using fresh fuel has been performed, as well as less conservative using burned fuel. The calculations include cross library generation for burned and fresh fuel for the ET-R R-1 fuel type. The WIMS-D 4 code has been used in library generation and burn up calculation the critically calculations are performed using the one dimensional transport code (ANISN) and the two dimensional diffusion code (DIXY2). The possibility of increasing the storage efficiency either by insertion of absorber sheets of soluble boron salts or by reduction of fuel rod separation has been studied. 8 figs., 2 tabs.

  7. Spent fuel storage criticality safety

    International Nuclear Information System (INIS)

    Amin, E.M.; Elmessiry, A.M.

    1995-01-01

    The safety aspects of the spent fuel storage pool of the Egyptian test and research reactor one (ET-R R-1) has to be assessed as part of a general overall safety evaluation to be included in a safety analysis report (SAR) for this reactor. The present work treats the criticality safety of the spent fuel storage pool. Conservative calculations based on using fresh fuel has been performed, as well as less conservative using burned fuel. The calculations include cross library generation for burned and fresh fuel for the ET-R R-1 fuel type. The WIMS-D 4 code has been used in library generation and burn up calculation the critically calculations are performed using the one dimensional transport code (ANISN) and the two dimensional diffusion code (DIXY2). The possibility of increasing the storage efficiency either by insertion of absorber sheets of soluble boron salts or by reduction of fuel rod separation has been studied. 8 figs., 2 tabs

  8. Demonstration of a transportable storage system for spent nuclear fuel

    International Nuclear Information System (INIS)

    Shetler, J.R.; Miller, K.R.; Jones, R.E.

    1993-01-01

    The purpose of this paper is to discuss the joint demonstration project between the Sacramento Municipal Utility District (SMUD) and the US Department of Energy (DOE) regarding the use of a transportable storage system for the long-term storage and subsequent transport of spent nuclear fuel. SMUD's Rancho Seco nuclear generating station was shut down permanently in June 1989. After the shutdown, SMUD began planning the decommissioning process, including the disposition of the spent nuclear fuel. Concurrently, Congress had directed the Secretary of Energy to develop a plan for the use of dual-purpose casks. Licensing and demonstrating a dual-purpose cask, or transportable storage system, would be a step toward achieving Congress's goal of demonstrating a technology that can be used to minimize the handling of spent nuclear fuel from the time the fuel is permanently removed from the reactor through to its ultimate disposal at a DOE facility. For SMUD, using a transportable storage system at the Rancho Seco Independent Spent-Fuel Storage Installation supports the goal of abandoning Rancho Seco's spent-fuel pool as decommissioning proceeds

  9. Spent fuel heatup following loss of water during storage

    International Nuclear Information System (INIS)

    Benjamin, A.S.; McCloskey, D.J.; Powers, D.A.; Dupree, S.A.

    1979-03-01

    An analysis of spent fuel heatup following a hypothetical accident involving drainage of the storage pool is presented. Computations based upon a new computer code called SFUEL have been performed to assess the effect of decay time, fuel element design, storage rack design, packing density, room ventilation, drainage level, and other variables on the heatup characteristics of the spent fuel and to predict the conditions under which clad failure will occur. Possible storage pool design modifications and/or onsite emergency action have also been considered

  10. Impact Analysis for Fuel Assemblies in Spent Fuel Storage Rack

    International Nuclear Information System (INIS)

    Oh, Jinho

    2013-01-01

    The design and structural integrity evaluation of a spent fuel storage rack (SFSR) utilized for storing and protecting the spent fuel assemblies generated during the operation of a reactor are very important in terms of nuclear safety and waste management. The objective of this study is to show the validity of the SFSR design as well as fuel assembly through a structural integrity evaluation based on a numerical analysis. In particular, a dynamic time history analysis considering the gaps between the fuel assemblies and the walls of the storage cell pipes in the SFSR was performed to check the structural integrity of the fuel assembly and storage cell pipe

  11. Impact Analysis for Fuel Assemblies in Spent Fuel Storage Rack

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Jinho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-07-01

    The design and structural integrity evaluation of a spent fuel storage rack (SFSR) utilized for storing and protecting the spent fuel assemblies generated during the operation of a reactor are very important in terms of nuclear safety and waste management. The objective of this study is to show the validity of the SFSR design as well as fuel assembly through a structural integrity evaluation based on a numerical analysis. In particular, a dynamic time history analysis considering the gaps between the fuel assemblies and the walls of the storage cell pipes in the SFSR was performed to check the structural integrity of the fuel assembly and storage cell pipe.

  12. A proposed Regulatory Guide basis for spent fuel decay heat

    International Nuclear Information System (INIS)

    Hermann, O.W.; Parks, C.V.; Renier, J.P.

    1991-01-01

    A proposed revision to Regulatory Guide 3.54, ''Spent Fuel Heat Generation in an Independent Spent Fuel Storage Installation'' has been developed for the US Nuclear Regulatory Commission. The proposed revision includes a data base of decay heat rates calculated as a function of burnup, specific power, cooling time, initial fuel 235 U enrichment and assembly type (i.e., PWR or BWR). Validation of the calculational method was done by comparison with existing measured decay heat rates. Procedures for proper use of the data base, adjustment formulae accounting for effects due to differences in operating history and initial enrichment, and a defensible safety factor were derived. 15 refs., 6 tabs

  13. Effect of spent engine oil on germination and growth parameters of ...

    African Journals Online (AJOL)

    This study investigated the effects of spent engine oil on the germination and growth parameters of fluted pumpkin (Telfairia occidentalis). Fluted pumpkin was grown on soils contaminated with 20ml, 40ml, 60ml, 80ml and 100ml of spent engine oil to obtain 1, 2, 3, 4 and 5% contaminations respectively and monitored for ...

  14. Partial Defect Verification of Spent Fuel Assemblies by PDET: Principle and Field Testing in Interim Spent Fuel Storage Facility (CLAB) in Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Ham, Y.S.; Kerr, P.; Sitaraman, S.; Swan, R. [Global Security Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Rossa, R. [SCK-CEN, Mol (Belgium); Liljenfeldt, H. [SKB in Oskarshamn (Sweden)

    2015-07-01

    The need for the development of a credible method and instrument for partial defect verification of spent fuel has been emphasized over a few decades in the safeguards communities as the diverted spent fuel pins can be the source of nuclear terrorism or devices. The need is increasingly more important and even urgent as many countries have started to transfer spent fuel to so called 'difficult-to-access' areas such as dry storage casks, reprocessing or geological repositories. Partial defect verification is required by IAEA before spent fuel is placed into 'difficult-to-access' areas. Earlier, Lawrence Livermore National Laboratory (LLNL) has reported the successful development of a new, credible partial defect verification method for pressurized water reactor (PWR) spent fuel assemblies without use of operator data, and further reported the validation experiments using commercial spent fuel assemblies with some missing fuel pins. The method was found to be robust as the method is relatively invariant to the characteristic variations of spent fuel assemblies such as initial fuel enrichment, cooling time, and burn-up. Since then, the PDET system has been designed and prototyped for 17x17 PWR spent fuel assemblies, complete with data acquisition software and acquisition electronics. In this paper, a summary description of the PDET development followed by results of the first successful field testing using the integrated PDET system and actual spent fuel assemblies performed in a commercial spent fuel storage site, known as Central Interim Spent fuel Storage Facility (CLAB) in Sweden will be presented. In addition to partial defect detection initial studies have determined that the tool can be used to verify the operator declared average burnup of the assembly as well as intra-assembly burnup levels. (authors)

  15. Device for removing a spent reactor core instrument tube

    International Nuclear Information System (INIS)

    Watanabe, Shigeru; Tsuji, Teruaki.

    1980-01-01

    Purpose: To easily and exactly execute works for removing a used reactor core instrument tube to be mounted in a reactor core from the lattice space of the core or for charging the tube into the lattice of the core. Constitution: When fuel assembly is pulled out of a reactor core and a spent reactor core instrument tube is then bent and removed from the core at periodical inspection time, a lower gripping unit integral with an upper gripping unit and a bending unit is provided at the lower end of a hanging rope of a winch, and lowered to the reactor core. Then, the spent reactor core instrument tube is gripped by the upper and lower gripping units, the bending unit is operated, the spent reactor core instrument tube is bent, and the tube is then pulled upwardly by the winch to remove the tube. (Aizawa, K.)

  16. Government--utility interaction on spent fuel disposition

    International Nuclear Information System (INIS)

    Mills, L.E.

    1978-01-01

    The question of the needs of the electrical power industry for spent fuel storage in light of the moratorium on fuel reprocessing is addressed. The author feels that since the Federal government has assumed the responsibility for spent fuel storage, it is imperative that a firm plan, program, legislation, and funding be forthcoming immediately. Designation of an existing government site with existing nuclear activities in order to expedite the establishment of a storage facility is recommended. It is felt that the timing for such a site should be ''at the earliest possible date.'' Without storage facilities being provided by the government, utilities will be forced to build storage facilities at the reactor sites. This course of action is not considered cost effective but certainly preferable to shutting down the reactors. It is emphasized that spent fuel storage must be an interim solution and certainly not a final solution to the fuel reprocessing and waste disposal aspects of nuclear technology

  17. Spent nuclear fuel project design basis capacity study

    Energy Technology Data Exchange (ETDEWEB)

    Cleveland, K.J.

    1996-09-09

    A parametric study of the Spent Nuclear Fuel Project system capacity is presented. The study was completed using a commercially available software package to develop a summary level model of the major project systems. Alternative configurations, sub-system cycle times, and operating scenarios were tested to identify their impact on total project duration and equipment requirements.

  18. Preliminary concepts for detecting national diversion of LWR spent fuel

    International Nuclear Information System (INIS)

    Sonnier, C.S.; Cravens, M.N.

    1978-04-01

    Preliminary concepts for detecting national diversion of LWR spent fuel during storage, handling and transportation are presented. Principal emphasis is placed on means to achieve timely detection by an international authority. This work was sponsored by the Department of Energy/Office of Safeguards and Security (DOE/OSS) as part of the overall Sandia Fixed Facility Physical Protection Program

  19. Investigation of a rotary valving system with variable valve timing for internal combustion engines

    Science.gov (United States)

    Cross, Paul C.; Hansen, Craig N.

    1994-11-01

    The objective of the program was to provide a functional demonstration of the Hansen Rotary Valving System with Variable Valve Timing (HRVS/VVT), capable of throttleless inlet charge control, as an alternative to conventional poppet-valves for use in spark ignited internal combustion engines. The goal of this new technology is to secure benefits in fuel economy, broadened torque band, vibration reduction, and overhaul accessibility. Additionally, use of the variable valve timing capability to vary the effective compression ratio is expected to improve multifuel tolerance and efficiency. Efforts directed at the design of HRVS components proved to be far more extensive than had been anticipated, ultimately requiring that proof-trial design/development work be performed. Although both time and funds were exhausted before optical or ion-probe types of in-cylinder investigation could be undertaken, a great deal of laboratory data was acquired during the course of the design/development work. This laboratory data is the basis for the information presented in this final report.

  20. Exciplex formation in bimolecular photoinduced electron-transfer investigated by ultrafast time-resolved infrared spectroscopy.

    Science.gov (United States)

    Koch, Marius; Letrun, Romain; Vauthey, Eric

    2014-03-12

    The dynamics of bimolecular photoinduced electron-transfer reactions has been investigated with three donor/acceptor (D/A) pairs in tetrahydrofuran (THF) and acetonitrile (ACN) using a combination of ultrafast spectroscopic techniques, including time-resolved infrared absorption. For the D/A pairs with the highest driving force of electron transfer, all transient spectroscopic features can be unambiguously assigned to the excited reactant and the ionic products. For the pair with the lowest driving force, three additional transient infrared bands, more intense in THF than in ACN, with a time dependence that differs from those of the other bands are observed. From their frequency and solvent dependence, these bands can be assigned to an exciplex. Moreover, polarization-resolved measurements point to a relatively well-defined mutual orientation of the constituents and to a slower reorientational time compared to those of the individual reactants. Thanks to the minimal overlap of the infrared signature of all transient species in THF, a detailed reaction scheme including the relevant kinetic and thermodynamic parameters could be deduced for this pair. This analysis reveals that the formation and recombination of the ion pair occur almost exclusively via the exciplex.