WorldWideScience

Sample records for field assessment methods

  1. DO TIE LABORATORY BASED ASSESSMENT METHODS REALLY PREDICT FIELD EFFECTS?

    Science.gov (United States)

    Sediment Toxicity Identification and Evaluation (TIE) methods have been developed for both porewaters and whole sediments. These relatively simple laboratory methods are designed to identify specific toxicants or classes of toxicants in sediments; however, the question of whethe...

  2. A field study comparing two methods of transportation risk assessment

    International Nuclear Information System (INIS)

    Harmon, M.F.; Brey, R.R.; Gesell, T.F.; Oberg, S.G.

    1996-01-01

    RADTRAN 4 is a computer code used for; assessing risks associated with the transportation of nuclear materials. The code employs the common modeling practice of using default values for input variables to simplify the modeling of complex scenarios, thus producing conservative final risk determinations. To better address local public concerns it is of interest to quantify the introduced conservatism by taking a site-specific approach to radiation risk assessment. With RISKIND, incident-free and accident condition doses were calculated for two suburban population groups using both default input parameters; and site-specific values to describe population demographics of regions in Pocatello, Idaho, along the I-15 corridor. The use of site-specific parameters resulted in incident-free doses ranging from the same order of magnitude to one order of magnitude less than the doses calculated with default input parameters. Correcting accident condition doses for the age distribution of the populations and employing site-specific weather data resulted in doses 1.1 times lower than estimated using default input parameters. Dose-risks calculated with RISKIND for the two population groups using site-specific data were of the same order of magnitude as the risk calculated using RADTRAN 4 for the suburban population described in DOE/EIS-0203-D. This study revealed in one specific application that use of default and site-specific parameters resulted in comparable dose estimates. If this tendency were to hold generally true over other environments and model variables, then risk assessors might prefer to select codes on the basis of criteria such as (1) the number of variables to select from; (2) ability to calculate consequences directly, and (3) outputs geared to addressing public concerns

  3. A method to assess soil erosion from smallholder farmers' fields: a case study from Malawi.

    Science.gov (United States)

    Mohamoud, Yusuf M

    2013-09-01

    Soil erosion by water is a major threat to sustainable food production systems in Africa. This study presents a qualitative soil erosion assessment method that links the number of broken ridges (NBRS) observed on a smallholder farmer's field after a rain event to factors of soil erosion (e.g., rainfall intensity, slope steepness, crop canopy height, and conservation practice) and to soil loss data measured from a runoff plot and receiving small streams. The assessment method consists of a rapid survey of smallholder farmers combined with field monitoring. Results show an indirect relationship between NBRS and factors of soil erosion. Results also show a direct relationship between NBRS and suspended sediment concentrations measured from an experimental runoff plot and receiving streams that drain the sub-watersheds where farmers' fields are located. Given the limited human and financial resources available to soil erosion research in developing countries, monitoring NBRS is a simple, cost-effective, and reliable erosion assessment method for regions where smallholder farmers practice contour ridging.

  4. Use of refractometry and colorimetry as field methods to rapidly assess antimalarial drug quality.

    Science.gov (United States)

    Green, Michael D; Nettey, Henry; Villalva Rojas, Ofelia; Pamanivong, Chansapha; Khounsaknalath, Lamphet; Grande Ortiz, Miguel; Newton, Paul N; Fernández, Facundo M; Vongsack, Latsamy; Manolin, Ot

    2007-01-04

    The proliferation of counterfeit and poor-quality drugs is a major public health problem; especially in developing countries lacking adequate resources to effectively monitor their prevalence. Simple and affordable field methods provide a practical means of rapidly monitoring drug quality in circumstances where more advanced techniques are not available. Therefore, we have evaluated refractometry, colorimetry and a technique combining both processes as simple and accurate field assays to rapidly test the quality of the commonly available antimalarial drugs; artesunate, chloroquine, quinine, and sulfadoxine. Method bias, sensitivity, specificity and accuracy relative to high-performance liquid chromatographic (HPLC) analysis of drugs collected in the Lao PDR were assessed for each technique. The HPLC method for each drug was evaluated in terms of assay variability and accuracy. The accuracy of the combined method ranged from 0.96 to 1.00 for artesunate tablets, chloroquine injectables, quinine capsules, and sulfadoxine tablets while the accuracy was 0.78 for enterically coated chloroquine tablets. These techniques provide a generally accurate, yet simple and affordable means to assess drug quality in resource-poor settings.

  5. A new method of quantitative cavitation assessment in the field of a lithotripter.

    Science.gov (United States)

    Jöchle, K; Debus, J; Lorenz, W J; Huber, P

    1996-01-01

    Transient cavitation seems to be a very important effect regarding the interaction of pulsed high-energy ultrasound with biologic tissues. Using a newly developed laser optical system we are able to determine the life-span of transient cavities (relative error less than +/- 5%) in the focal region of a lithotripter (Lithostar, Siemens). The laser scattering method is based on the detection of scattered laser light reflected during a bubble's life. This method requires no sort of sensor material in the pathway of the sound field. Thus, the method avoids any interference with bubble dynamics during the measurement. The knowledge of the time of bubble decay allows conclusions to be reached on the destructive power of the cavities. By combining the results of life-span measurements with the maximum bubble radius using stroboscopic photographs we found that the measured time of bubble decay and the predicted time using Rayleigh's law only differs by about 13% even in the case of complex bubble fields. It can be shown that the laser scattering method is feasible to assess cavitation events quantitatively. Moreover, it will enable us to compare different medical ultrasound sources that have the capability to generate cavitation.

  6. Validation of Field Methods to Assess Body Fat Percentage in Elite Youth Soccer Players.

    Science.gov (United States)

    Munguia-Izquierdo, Diego; Suarez-Arrones, Luis; Di Salvo, Valter; Paredes-Hernandez, Victor; Alcazar, Julian; Ara, Ignacio; Kreider, Richard; Mendez-Villanueva, Alberto

    2018-05-01

    This study determined the most effective field method for quantifying body fat percentage in male elite youth soccer players and developed prediction equations based on anthropometric variables. Forty-four male elite-standard youth soccer players aged 16.3-18.0 years underwent body fat percentage assessments, including bioelectrical impedance analysis and the calculation of various skinfold-based prediction equations. Dual X-ray absorptiometry provided a criterion measure of body fat percentage. Correlation coefficients, bias, limits of agreement, and differences were used as validity measures, and regression analyses were used to develop soccer-specific prediction equations. The equations from Sarria et al. (1998) and Durnin & Rahaman (1967) reached very large correlations and the lowest biases, and they reached neither the practically worthwhile difference nor the substantial difference between methods. The new youth soccer-specific skinfold equation included a combination of triceps and supraspinale skinfolds. None of the practical methods compared in this study are adequate for estimating body fat percentage in male elite youth soccer players, except for the equations from Sarria et al. (1998) and Durnin & Rahaman (1967). The new youth soccer-specific equation calculated in this investigation is the only field method specifically developed and validated in elite male players, and it shows potentially good predictive power. © Georg Thieme Verlag KG Stuttgart · New York.

  7. Near-field hazard assessment of March 11, 2011 Japan Tsunami sources inferred from different methods

    Science.gov (United States)

    Wei, Y.; Titov, V.V.; Newman, A.; Hayes, G.; Tang, L.; Chamberlin, C.

    2011-01-01

    Tsunami source is the origin of the subsequent transoceanic water waves, and thus the most critical component in modern tsunami forecast methodology. Although impractical to be quantified directly, a tsunami source can be estimated by different methods based on a variety of measurements provided by deep-ocean tsunameters, seismometers, GPS, and other advanced instruments, some in real time, some in post real-time. Here we assess these different sources of the devastating March 11, 2011 Japan tsunami by model-data comparison for generation, propagation and inundation in the near field of Japan. This study provides a comparative study to further understand the advantages and shortcomings of different methods that may be potentially used in real-time warning and forecast of tsunami hazards, especially in the near field. The model study also highlights the critical role of deep-ocean tsunami measurements for high-quality tsunami forecast, and its combination with land GPS measurements may lead to better understanding of both the earthquake mechanisms and tsunami generation process. ?? 2011 MTS.

  8. An Exploration of Alternative Assessment Methods for the Field of Education: From the Fields of Law and Medicine.

    Science.gov (United States)

    Paule, Lynde; Murray, Stephen L.

    As a precursor to making recommendations for more effective assessment methods for teacher certification, an examination is made of the professions of law and medicine. Specifically, the examination covers the relationship between training programs and the methods employed for evaluating prospective lawyers and doctors to ensure that they have the…

  9. Are rapid population estimates accurate? A field trial of two different assessment methods.

    Science.gov (United States)

    Grais, Rebecca F; Coulombier, Denis; Ampuero, Julia; Lucas, Marcelino E S; Barretto, Avertino T; Jacquier, Guy; Diaz, Francisco; Balandine, Serge; Mahoudeau, Claude; Brown, Vincent

    2006-09-01

    Emergencies resulting in large-scale displacement often lead to populations resettling in areas where basic health services and sanitation are unavailable. To plan relief-related activities quickly, rapid population size estimates are needed. The currently recommended Quadrat method estimates total population by extrapolating the average population size living in square blocks of known area to the total site surface. An alternative approach, the T-Square, provides a population estimate based on analysis of the spatial distribution of housing units taken throughout a site. We field tested both methods and validated the results against a census in Esturro Bairro, Beira, Mozambique. Compared to the census (population: 9,479), the T-Square yielded a better population estimate (9,523) than the Quadrat method (7,681; 95% confidence interval: 6,160-9,201), but was more difficult for field survey teams to implement. Although applicable only to similar sites, several general conclusions can be drawn for emergency planning.

  10. Using Educational Data Mining Methods to Assess Field-Dependent and Field-Independent Learners' Complex Problem Solving

    Science.gov (United States)

    Angeli, Charoula; Valanides, Nicos

    2013-01-01

    The present study investigated the problem-solving performance of 101 university students and their interactions with a computer modeling tool in order to solve a complex problem. Based on their performance on the hidden figures test, students were assigned to three groups of field-dependent (FD), field-mixed (FM), and field-independent (FI)…

  11. Biomass energy use at the household level in two villages of Bangladesh: assessment of field methods

    International Nuclear Information System (INIS)

    Bari, M.N.; Bangladesh Agricultural University; Hall, D.O.; Lucas, N.J.D.; Hossain, S.M.A.

    1998-01-01

    A study was conducted to assess biomass energy supply and use in two villages in different agro-ecological regions of Bangladesh using three different techniques: broad questionnaire survey, sample questionnaire survey, and physical monitoring in order to see which methodology was more appropriate for the accurate assessment of biomass cooking energy supply and demand. The study included four broad socio-economic groups, i.e. large, medium, small and landless households. It was found that, per capita cooking energy demand varied significantly between the villages, socio-economic groups, and the first two methods of survey. Energy used was found to be strongly correlated with family size and energy use decreased according to landholding size. The broad questionnaire survey showed an average cooking energy use of 11.8 and 10.1 GJ per capita/year, for Kazirshimla and Noagaon village, respectively, while the sample questionnaire survey estimated energy use at 9.2 an 8.5 GJ per capita/year. With physical monitoring, however, the respective figures were found as 9.0 and 8.2 GJ per capita/year. It was also found that energy use was at the subsistence level in both villages. In Kazirishimla village biomass supply was found to be marginally surplus to use, while Noagaon had a supply deficit. The study showed that a broad questionnaire survey gives a fairly general picture of both biomass supply and use, but to assess cooking energy use more accurately successive sample questionnaire surveys followed by physical monitoring are more effective. (author)

  12. A rigorous assessment of tree height measurements obtained using airborne LIDAR and conventional field methods.

    Science.gov (United States)

    Hans-Erik Andersen; Stephen E. Reutebuch; Robert J. McGaughey

    2006-01-01

    Tree height is an important variable in forest inventory programs but is typically time-consuming and costly to measure in the field using conventional techniques. Airborne light detection and ranging (LIDAR) provides individual tree height measurements that are highly correlated with field-derived measurements, but the imprecision of conventional field techniques does...

  13. Field calibration of blowfly-derived DNA against traditional methods for assessing mammal diversity in tropical forests.

    Science.gov (United States)

    Lee, Ping-Shin; Gan, Han Ming; Clements, Gopalasamy Reuben; Wilson, John-James

    2016-11-01

    Mammal diversity assessments based on DNA derived from invertebrates have been suggested as alternatives to assessments based on traditional methods; however, no study has field-tested both approaches simultaneously. In Peninsular Malaysia, we calibrated the performance of mammal DNA derived from blowflies (Diptera: Calliphoridae) against traditional methods used to detect species. We first compared five methods (cage trapping, mist netting, hair trapping, scat collection, and blowfly-derived DNA) in a forest reserve with no recent reports of megafauna. Blowfly-derived DNA and mist netting detected the joint highest number of species (n = 6). Only one species was detected by multiple methods. Compared to the other methods, blowfly-derived DNA detected both volant and non-volant species. In another forest reserve, rich in megafauna, we calibrated blowfly-derived DNA against camera traps. Blowfly-derived DNA detected more species (n = 11) than camera traps (n = 9), with only one species detected by both methods. The rarefaction curve indicated that blowfly-derived DNA would continue to detect more species with greater sampling effort. With further calibration, blowfly-derived DNA may join the list of traditional field methods. Areas for further investigation include blowfly feeding and dispersal biology, primer biases, and the assembly of a comprehensive and taxonomically-consistent DNA barcode reference library.

  14. A method for assessing occupational exposure to power-frequency magnetic fields for electricity generation and transmission workers

    International Nuclear Information System (INIS)

    Renew, D C; Cook, R F; Ball, M C

    2003-01-01

    A new method for assessing both current and historical occupational exposures to magnetic fields has been developed and used in health studies involving a cohort of electricity generation and transmission workers in England and Wales. The exposure values are derived by calculation from engineering and operational data about the power stations rather than from measurements. They are provided for each of 11 job categories for each year of operation of each power station represented in the cohort. The engineering data are used to determine the average magnetic fields in specified areas of work within the power station and then applied to information about the time spent in these areas by each of the job categories. The operational data are used to adjust the exposures for each year according to the power station output for the year. Earlier methods used measurements or the advice of panels of experts to provide exposure scores for a number of job categories across all power stations and years. Such methods were not able to distinguish exposures from different power facilities or during the different years of their operation. Measurement surveys at 10 power stations of the magnetic fields in the work areas gave confidence that the calculations were realistic. Exposure measurements on 215 workers at three power stations were compared in job groups with the exposures predicted by the method. The Pearson correlation coefficient was 0.86 and the slope and intercept of the line of best fit were 0.87 and 0.07 μT respectively. The method gives a good prediction of measured exposure and is being used for studies of occupational exposure to magnetic fields and leukaemia, and of cardiovascular disease, and a reanalysis of brain cancer

  15. Application of field methods to assess isometamidium resistance of trypanosomes in cattle in western Ethiopia

    DEFF Research Database (Denmark)

    Tewelde, N.; Abebe, G.; Eisler, M.

    2004-01-01

    This study assessed the degree of isometamidium resistance of trypanosomes infecting cattle in the upper Didessa valley of western Ethiopia. An initial prevalence study was conducted to identify sites with a high risk of trypanosmosis in cattle. The trypanosome prevalence varied widely, with two...

  16. Assessing Methods for Mapping 2D Field Concentrations of CO2 Over Large Spatial Areas for Monitoring Time Varying Fluctuations

    Science.gov (United States)

    Zaccheo, T. S.; Pernini, T.; Botos, C.; Dobler, J. T.; Blume, N.; Braun, M.; Levine, Z. H.; Pintar, A. L.

    2014-12-01

    This work presents a methodology for constructing 2D estimates of CO2 field concentrations from integrated open path measurements of CO2 concentrations. It provides a description of the methodology, an assessment based on simulated data and results from preliminary field trials. The Greenhouse gas Laser Imaging Tomography Experiment (GreenLITE) system, currently under development by Exelis and AER, consists of a set of laser-based transceivers and a number of retro-reflectors coupled with a cloud-based compute environment to enable real-time monitoring of integrated CO2 path concentrations, and provides 2D maps of estimated concentrations over an extended area of interest. The GreenLITE transceiver-reflector pairs provide laser absorption spectroscopy (LAS) measurements of differential absorption due to CO2 along intersecting chords within the field of interest. These differential absorption values for the intersecting chords of horizontal path are not only used to construct estimated values of integrated concentration, but also employed in an optimal estimation technique to derive 2D maps of underlying concentration fields. This optimal estimation technique combines these sparse data with in situ measurements of wind speed/direction and an analytic plume model to provide tomographic-like reconstruction of the field of interest. This work provides an assessment of this reconstruction method and preliminary results from the Fall 2014 testing at the Zero Emissions Research and Technology (ZERT) site in Bozeman, Montana. This work is funded in part under the GreenLITE program developed under a cooperative agreement between Exelis and the National Energy and Technology Laboratory (NETL) under the Department of Energy (DOE), contract # DE-FE0012574. Atmospheric and Environmental Research, Inc. is a major partner in this development.

  17. A Multi-Methods Approach to HRA and Human Performance Modeling: A Field Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Jacques Hugo; David I Gertman

    2012-06-01

    The Advanced Test Reactor (ATR) is a research reactor at the Idaho National Laboratory is primarily designed and used to test materials to be used in other, larger-scale and prototype reactors. The reactor offers various specialized systems and allows certain experiments to be run at their own temperature and pressure. The ATR Canal temporarily stores completed experiments and used fuel. It also has facilities to conduct underwater operations such as experiment examination or removal. In reviewing the ATR safety basis, a number of concerns were identified involving the ATR canal. A brief study identified ergonomic issues involving the manual handling of fuel elements in the canal that may increase the probability of human error and possible unwanted acute physical outcomes to the operator. In response to this concern, that refined the previous HRA scoping analysis by determining the probability of the inadvertent exposure of a fuel element to the air during fuel movement and inspection was conducted. The HRA analysis employed the SPAR-H method and was supplemented by information gained from a detailed analysis of the fuel inspection and transfer tasks. This latter analysis included ergonomics, work cycles, task duration, and workload imposed by tool and workplace characteristics, personal protective clothing, and operational practices that have the potential to increase physical and mental workload. Part of this analysis consisted of NASA-TLX analyses, combined with operational sequence analysis, computational human performance analysis (CHPA), and 3D graphical modeling to determine task failures and precursors to such failures that have safety implications. Experience in applying multiple analysis techniques in support of HRA methods is discussed.

  18. A Multi-Methods Approach to HRA and Human Performance Modeling: A Field Assessment

    International Nuclear Information System (INIS)

    Hugo, Jacques; Gertman, David I.

    2012-01-01

    The Advanced Test Reactor (ATR) is a research reactor at the Idaho National Laboratory is primarily designed and used to test materials to be used in other, larger-scale and prototype reactors. The reactor offers various specialized systems and allows certain experiments to be run at their own temperature and pressure. The ATR Canal temporarily stores completed experiments and used fuel. It also has facilities to conduct underwater operations such as experiment examination or removal. In reviewing the ATR safety basis, a number of concerns were identified involving the ATR canal. A brief study identified ergonomic issues involving the manual handling of fuel elements in the canal that may increase the probability of human error and possible unwanted acute physical outcomes to the operator. In response to this concern, that refined the previous HRA scoping analysis by determining the probability of the inadvertent exposure of a fuel element to the air during fuel movement and inspection was conducted. The HRA analysis employed the SPAR-H method and was supplemented by information gained from a detailed analysis of the fuel inspection and transfer tasks. This latter analysis included ergonomics, work cycles, task duration, and workload imposed by tool and workplace characteristics, personal protective clothing, and operational practices that have the potential to increase physical and mental workload. Part of this analysis consisted of NASA-TLX analyses, combined with operational sequence analysis, computational human performance analysis (CHPA), and 3D graphical modeling to determine task failures and precursors to such failures that have safety implications. Experience in applying multiple analysis techniques in support of HRA methods is discussed.

  19. Application and problems of probability methods in technical safety assessment in the field of nuclear engineering and other technologies

    International Nuclear Information System (INIS)

    Heuser, F.W.

    1980-01-01

    On the basis of a deterministic safety concept that has been developed in nuclear engineering, approaches for a probabilistic interpretation of existing safety requirements and for a further risk assessment are described. The procedures in technical reliability analysis and its application in nuclear engineering are discussed. By the example of a reliability analysis for a reactor protection system the author discusses the question as to what extent methods of reliability analysis can be used to interpret deterministically derived safety requirements. The the author gives a survey of the current value and application of probabilistic reliability assessments in non-nuclear technology. The last part of this report deals with methods of risk analysis and its use for safety assessment in nuclear engineering. On the basis of WASH 1,400 the most important phases and tasks of research work in risk assessment are explained, showing the basic criteria and the methods to be applied in risk analysis. (orig./HSCH) [de

  20. PERFORMANCE ASSESSMENT FOR FIELD SPORTS

    Directory of Open Access Journals (Sweden)

    Christopher Carling

    2009-03-01

    Full Text Available DESCRIPTION The book covers the various sport science assessment procedures for sports such as soccer, rugby, field hockey and lacrosse. It provides detailed and clear information about laboratory and field-based methods that can be used to assess and improve both individual and team performance. PURPOSE The book aims to provide a contemporary reference tool for selection of appropriate testing procedures for sports across a range of scientific disciplines. FEATURES The text begins with a chapter on the rationales for performance assessments, the use of technology and the necessity for procedures to conform to scientific rigor, explaining the importance of test criteria. This chapter ends by emphasizing the importance of the feedback process and vital considerations for the practitioner when interpreting the data, selecting which information is most important and how to deliver this back to the athlete or coach in order to deliver a positive performance outcome. The next two chapters focus on psychological assessments with respect to skill acquisition, retention and execution providing a variety of qualitative and quantitative options, underpinned with scientific theory and contextualized in order to improve the understanding of the application of these methods to improve anticipation and decision-making to enhance game intelligence.Chapter 4 provides coverage of match analysis techniques in order to make assessments of technical, tactical and physical performances. Readers learn about a series of methodologies ranging from simplistic pen and paper options through to sophisticated technological systems with some exemplar data also provided. Chapters 5 through 7 cover the physiological based assessments, including aerobic, anaerobic and anthropometric procedures. Each chapter delivers a theoretical opening section before progressing to various assessment options and the authors make great efforts to relate to sport-specific settings. The final

  1. An assessment on preparation methods and applications of hydrophobic Pt-catalyst in nuclear and environmental field

    International Nuclear Information System (INIS)

    Ionita, Gh.; Stefanescu, I.; Varlam, Carmen

    2001-01-01

    Based on the long experience of the authors in the preparation, testing and evaluation of the performances of hydrophobic catalysts and based on the reviewed references, this paper presents up-to-date R and D activities on the preparation and application of hydrophobic catalysts for use in nuclear and environmental fields. Unlike the conventional hydrophilic catalysts, the hydrophobic catalysts repel the liquid water and allow the transport of the gaseous reactants and reaction products to and from catalytic active centers. For deuterium and tritium separation, over one hundred hydrophobic catalyst types have been prepared in different experimental conditions and by a large diversity of wet proofing methods. The influence of about twenty parameters on catalytic activity have been also studied. The purpose of this paper is: (1) to provide a database for preparation and selection of he most appropriate method for preparing an active hydrophobic catalyst, (2) to show how to use the hydrophobic catalyst and how to operate efficiently the reactor packed with hydrophobic catalyst, (3) to evaluate the performances and potentiality of hydrophobic catalysts in nuclear and environmental field, (4) evaluation of applications of hydrophobic catalysts in nuclear and environmental fields. As result, the following categories are shown: (1) the hydrophobic catalysts based on platinum and Teflon as wet-proofing proved to have the highest activity and the longest stability, (2) the utilization of hydrophobic catalyst as ordered mixed catalytic packing in the trickle bed or separated bed reactors is more efficient and has been entirely proved on industrial scale for tritium separation process, (3) the extension of the applications of hydrophobic catalysts for other processes which take place in the presence of saturated humidity or liquid water in environmental protection field. The merits of hydrophobic Pt-catalysts for tritium separation are discussed in comparison to other

  2. Laboratory Validation and Field Assessment of Petroleum Laboratory Technicians' Dermal Exposure to Crude Oil Using a Wipe Sampling Method.

    Science.gov (United States)

    Galea, Karen S; Mueller, Will; Arfaj, Ayman M; Llamas, Jose L; Buick, Jennifer; Todd, David; McGonagle, Carolyn

    2018-05-21

    Crude oil may cause adverse dermal effects therefore dermal exposure is an exposure route of concern. Galea et al. (2014b) reported on a study comparing recovery (wipe) and interception (cotton glove) dermal sampling methods. The authors concluded that both methods were suitable for assessing dermal exposure to oil-based drilling fluids and crude oil but that glove samplers may overestimate the amount of fluid transferred to the skin. We describe a study which aimed to further evaluate the wipe sampling method to assess dermal exposure to crude oil, with this assessment including extended sample storage periods and sampling efficiency tests being undertaken at environmental conditions to mimic those typical of outdoor conditions in Saudi Arabia. The wipe sampling method was then used to assess the laboratory technicians' actual exposure to crude oil during typical petroleum laboratory tasks. Overall, acceptable storage efficiencies up to 54 days were reported with results suggesting storage stability over time. Sampling efficiencies were also reported to be satisfactory at both ambient and elevated temperature and relative humidity environmental conditions for surrogate skin spiked with known masses of crude oil and left up to 4 h prior to wiping, though there was an indication of reduced sampling efficiency over time. Nineteen petroleum laboratory technicians provided a total of 35 pre- and 35 post-activity paired hand wipe samples. Ninety-three percent of the pre-exposure paired hand wipes were less than the analytical limit of detection (LOD), whereas 46% of the post-activity paired hand wipes were less than the LOD. The geometric mean paired post-activity wipe sample measurement was 3.09 µg cm-2 (range 1.76-35.4 µg cm-2). It was considered that dermal exposure most frequently occurred through direct contact with the crude oil (emission) or via deposition. The findings of this study suggest that the wipe sampling method is satisfactory in quantifying

  3. Methods for magnetostatic field calculation

    International Nuclear Information System (INIS)

    Vorozhtsov, S.B.

    1984-01-01

    Two methods for magnetostatic field calculation: differential and integrat are considered. Both approaches are shown to have certain merits and drawbacks, choice of the method depend on the type of the solved problem. An opportunity of combination of these tWo methods in one algorithm (hybrid method) is considered

  4. The Plastic Tension Field Method

    DEFF Research Database (Denmark)

    Hansen, Thomas

    2005-01-01

    This paper describes a calculation method for steel plate girders with transverse web stiffeners subjected to shear. It may be used for predicting the failure load or, as a design method, to determine the optimal amount of internal web stiffeners. The new method is called the plastic tension field...... method. The method is based on the theory of plasticity and is analogous to the so-called diagonal compression field method developed for reinforced concrete beams with transverse stirrups, which is adopted in the common European concrete code (Eurocode 2). Many other theories have been developed...

  5. Damage assessment using advanced non-intrusive inspection methods: integration of space, UAV, GPR, and field spectroscopy

    Science.gov (United States)

    Themistocleous, Kyriacos; Neocleous, Kyriacos; Pilakoutas, Kypros; Hadjimitsis, Diofantos G.

    2014-08-01

    The predominant approach for conducting road condition surveys and analyses is still largely based on extensive field observations. However, visual assessment alone cannot identify the actual extent and severity of damage. New non-invasive and cost-effective non-destructive (NDT) remote sensing technologies can be used to monitor road pavements across their life cycle, including remotely sensed aerial and satellite visual and thermal image (AI) data, Unmanned Aerial Vehicles (UAVs), Spectroscopy and Ground Penetrating Radar (GRP). These non-contact techniques can be used to obtain surface and sub-surface information about damage in road pavements, including the crack depth, and in-depth structural failure. Thus, a smart and cost-effective methodology is required that integrates several of these non-destructive/ no-contact techniques for the damage assessment and monitoring at different levels. This paper presents an overview of how an integration of the above technologies can be used to conduct detailed road condition surveys. The proposed approach can also be used to predict the future needs for road maintenance; this information is proven to be valuable to a strategic decision making tools that optimizes maintenance based on resources and environmental issues.

  6. Application and problems of probability methods in technical safety assessment in the field of nuclear engineering and other technologies

    International Nuclear Information System (INIS)

    Mathiak, E.; Schuetz, B.

    1980-01-01

    The authors explain purpose, latest developments and application of probabilistic methods in safety assessments of nuclear facilities, and of non-nuclear installations. Their findings show that the methods of probabilistic systems analysis and of structural reliability analysis proved to be successful, above all with regard to systematics and reproducibility. Above all probabilistic systems analyses have been applied to a large extent in the Rasmussen study. Although this study has been intended to present objective information on the risks to be expected from nuclear power plant operation, the results of the study have not been accepted by the public as an unbiased presentation. It is worth mentioning that in the opinion of a number of social scientists, solutions accepted by the whole of society cannot be reached by defining and adhering to risk standards, but rather by entering into discussions with those groups directly affected, working out compromises meeting all interests. Risk analyses supply information that facilitates practical planning of emergency measures. A description of probable accidents allows conclusions to be drawn in terms of quality and quantity as to how and to what extent appropriate precautionary measures can be taken and planned. Risk analyses offer the possibility of preventing damage hitherto known only by experience (e.g. through accident analyses) by precalculating possible events, and then initiating the required improvements. It is these positive effects that make up the importance of such analyses. (orig./HSCH) [de

  7. Improvements of the Profil Cultural Method for a better Low-tech Field Assessment of Soil Structure under no-till

    Science.gov (United States)

    Roger-Estrade, Jean; Boizard, Hubert; Peigné, Josephine; Sasal, Maria Carolina; Guimaraes, Rachel; Piron, Denis; Tomis, Vincent; Vian, Jean-François; Cadoux, Stephane; Ralisch, Ricardo; Filho, Tavares; Heddadj, Djilali; de Battista, Juan; Duparque, Annie

    2016-04-01

    In France, agronomists have studied the effects of cropping systems on soil structure, using a field method based on a visual description of soil structure. The "profil cultural" method (Manichon and Gautronneau, 1987) has been designed to perform a field diagnostic of the effects of tillage and compaction on soil structure dynamics. This method is of great use to agronomists improving crop management for a better preservation of soil structure. However, this method was developed and mainly used in conventional tillage systems, with ploughing. As several forms of reduced, minimum and no tillage systems are expanding in many parts of the world, it is necessary to re-evaluate the ability of this method to describe and interpret soil macrostructure in unploughed situations. In unploughed fields, soil structure dynamics of untilled layers is mainly driven by compaction and regeneration by natural agents (climatic conditions, root growth and macrofauna) and it is of major importance to evaluate the importance of these natural processes on soil structure regeneration. These concerns have led us to adapt the standard method and to propose amendments based on a series of field observations and experimental work in different situations of cropping systems, soil types and climatic conditions. We improved the description of crack type and we introduced an index of biological activity, based on the visual examination of clods. To test the improved method, a comparison with the reference method was carried out and the ability of the "profil cultural" method to make a diagnosis was tested on five experiments in France, Brazil and Argentina. Using the improved method, the impact of cropping systems on soil functioning was better assessed when natural processes were integrated into the description.

  8. Energy consumption assessment methods

    Energy Technology Data Exchange (ETDEWEB)

    Sutherland, K S

    1975-01-01

    The why, what, and how-to aspects of energy audits for industrial plants, and the application of energy accounting methods to a chemical plant in order to assess energy conservation possibilities are discussed. (LCL)

  9. WATER CHEMISTRY ASSESSMENT METHODS

    Science.gov (United States)

    This section summarizes and evaluates the surfce water column chemistry assessment methods for USEPA/EMAP-SW, USGS-NAQA, USEPA-RBP, Oho EPA, and MDNR-MBSS. The basic objective of surface water column chemistry assessment is to characterize surface water quality by measuring a sui...

  10. Methods for assessing geodiversity

    Science.gov (United States)

    Zwoliński, Zbigniew; Najwer, Alicja; Giardino, Marco

    2017-04-01

    The accepted systematics of geodiversity assessment methods will be presented in three categories: qualitative, quantitative and qualitative-quantitative. Qualitative methods are usually descriptive methods that are suited to nominal and ordinal data. Quantitative methods use a different set of parameters and indicators to determine the characteristics of geodiversity in the area being researched. Qualitative-quantitative methods are a good combination of the collection of quantitative data (i.e. digital) and cause-effect data (i.e. relational and explanatory). It seems that at the current stage of the development of geodiversity research methods, qualitative-quantitative methods are the most advanced and best assess the geodiversity of the study area. Their particular advantage is the integration of data from different sources and with different substantive content. Among the distinguishing features of the quantitative and qualitative-quantitative methods for assessing geodiversity are their wide use within geographic information systems, both at the stage of data collection and data integration, as well as numerical processing and their presentation. The unresolved problem for these methods, however, is the possibility of their validation. It seems that currently the best method of validation is direct filed confrontation. Looking to the next few years, the development of qualitative-quantitative methods connected with cognitive issues should be expected, oriented towards ontology and the Semantic Web.

  11. Assessment of inhomogeneous ELF magnetic field exposures

    International Nuclear Information System (INIS)

    Leitgeb, N.; Cech, R.; Schroettner, J.

    2008-01-01

    In daily life as well as at workplaces, exposures to inhomogeneous magnetic fields become very frequent. This makes easily applicable compliance assessment methods increasingly important. Reference levels have been defined linking basic restrictions to levels of homogeneous fields at worst-case exposure conditions. If reference levels are met, compliance with basic restrictions can be assumed. If not, further investigations could still prove compliance. Because of the lower induction efficiency, inhomogeneous magnetic fields such as from electric appliances could be allowed exceeding reference levels. To easily assess inhomogeneous magnetic fields, a quick and flexible multi-step assessment procedure is proposed. On the basis of simulations with numerical, anatomical human models reference factors were calculated elevating reference levels to link hot-spot values measured at source surfaces to basic limits and allowing accounting for different source distance, size, orientation and position. Compliance rules are proposed minimising assessment efforts. (authors)

  12. Variational methods for field theories

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Menahem, S.

    1986-09-01

    Four field theory models are studied: Periodic Quantum Electrodynamics (PQED) in (2 + 1) dimensions, free scalar field theory in (1 + 1) dimensions, the Quantum XY model in (1 + 1) dimensions, and the (1 + 1) dimensional Ising model in a transverse magnetic field. The last three parts deal exclusively with variational methods; the PQED part involves mainly the path-integral approach. The PQED calculation results in a better understanding of the connection between electric confinement through monopole screening, and confinement through tunneling between degenerate vacua. This includes a better quantitative agreement for the string tensions in the two approaches. Free field theory is used as a laboratory for a new variational blocking-truncation approximation, in which the high-frequency modes in a block are truncated to wave functions that depend on the slower background modes (Boron-Oppenheimer approximation). This ''adiabatic truncation'' method gives very accurate results for ground-state energy density and correlation functions. Various adiabatic schemes, with one variable kept per site and then two variables per site, are used. For the XY model, several trial wave functions for the ground state are explored, with an emphasis on the periodic Gaussian. A connection is established with the vortex Coulomb gas of the Euclidean path integral approach. The approximations used are taken from the realms of statistical mechanics (mean field approximation, transfer-matrix methods) and of quantum mechanics (iterative blocking schemes). In developing blocking schemes based on continuous variables, problems due to the periodicity of the model were solved. Our results exhibit an order-disorder phase transition. The transfer-matrix method is used to find a good (non-blocking) trial ground state for the Ising model in a transverse magnetic field in (1 + 1) dimensions.

  13. Assessment of reflectivity of noise barriers in the far field – QUIESST method compared to traditional approach

    NARCIS (Netherlands)

    Roo, F. de

    2013-01-01

    The sound reflectivity of noise barriers elements is one of the major acoustic product characteristics. Traditionally this property was tested in reverberation rooms according to EN 1793-1 and the results were used to predict the effect of sound reflections in the far field. As in many cases these

  14. Assessment methods for rehabilitation.

    Science.gov (United States)

    Biefang, S; Potthoff, P

    1995-09-01

    Diagnostics and evaluation in medical rehabilitation should be based on methods that are as objective as possible. In this context quantitative methods are an important precondition. We conducted for the German Pensions Insurance Institutions (which are in charge of the medical and vocational rehabilitation of workers and employees) a survey on assessment methods for rehabilitation which included an evaluation of American literature, with the aim to indicate procedures that can be considered for adaptation in Germany and to define further research requirements. The survey identified: (1) standardized procedures and instrumented tests for the assessment of musculoskeletal, cardiopulmonary and neurophysiological function; (2) personality, intelligence, achievement, neuropsychological and alcoholism screening tests for the assessment of mental or cognitive function; (3) rating scales and self-administered questionnaires for the assessment of Activities of Daily Living and Instrumental Activities of Daily Living (ADL/IADL Scales); (4) generic profiles and indexes as well as disease-specific measures for the assessment of health-related quality of life and health status; and (5) rating scales for vocational assessment. German equivalents or German versions exist only for a part of the procedures identified. Translation and testing of Anglo-Saxon procedures should have priority over the development of new German methods. The following procedures will be taken into account: (a) instrumented tests for physical function, (b) IADL Scales, (c) generic indexes of health-related quality of life, (d) specific quality of life and health status measures for disorders of the circulatory system, metabolic system, digestive organs, respiratory tract and for cancer, and (e) vocational rating scales.

  15. French experience in the field of internal dosimetry assessment at a nuclear workplace. Methods and results on industrial uranium dioxide

    International Nuclear Information System (INIS)

    Ansoborlo, E.; Henge-Napoli, M.H.; Rannou, A.; Pihet, P.; Dewez, P.

    1995-01-01

    The implementation of the new ICRP recommendations and the diversity of industrial exposure materials make it necessary to modify our approach of assessing internal dosimetry. This paper describes a methodology developed to asses different parameters such as activity concentration and particle size distribution at the workplace; physico-chemical characteristics of industrial dust handled; and in vitro and in vivo solubility in order to determine the absorption rate blood. The determination of such specific parameters will lead to dose calculation in terms of committed effective Dose Per Unit of Intake (DPUI). Results obtained for an industrial uranium dioxide, UO 2 , at a French nuclear facility are presented. (author). 21 refs., 2 figs., 4 tabs

  16. On the computational assessment of white matter hyperintensity progression: difficulties in method selection and bias field correction performance on images with significant white matter pathology

    Energy Technology Data Exchange (ETDEWEB)

    Valdes Hernandez, Maria del C.; Gonzalez-Castro, Victor; Wang, Xin; Doubal, Fergus; Munoz Maniega, Susana; Wardlaw, Joanna M. [Centre for Clinical Brian Sciences, Department of Neuroimaging Sciences, Edinburgh (United Kingdom); Ghandour, Dina T. [University of Edinburgh, College of Medicine and Veterinary Medicine, Edinburgh (United Kingdom); Armitage, Paul A. [University of Sheffield, Department of Cardiovascular Sciences, Sheffield (United Kingdom)

    2016-05-15

    Subtle inhomogeneities in the scanner's magnetic fields (B{sub 0} and B{sub 1}) alter the intensity levels of the structural magnetic resonance imaging (MRI) affecting the volumetric assessment of WMH changes. Here, we investigate the influence that (1) correcting the images for the B{sub 1} inhomogeneities (i.e. bias field correction (BFC)) and (2) selection of the WMH change assessment method can have on longitudinal analyses of WMH progression and discuss possible solutions. We used brain structural MRI from 46 mild stroke patients scanned at stroke onset and 3 years later. We tested three BFC approaches: FSL-FAST, N4 and exponentially entropy-driven homomorphic unsharp masking (E{sup 2}D-HUM) and analysed their effect on the measured WMH change. Separately, we tested two methods to assess WMH changes: measuring WMH volumes independently at both time points semi-automatically (MCMxxxVI) and subtracting intensity-normalised FLAIR images at both time points following image gamma correction. We then combined the BFC with the computational method that performed best across the whole sample to assess WMH changes. Analysis of the difference in the variance-to-mean intensity ratio in normal tissue between BFC and uncorrected images and visual inspection showed that all BFC methods altered the WMH appearance and distribution, but FSL-FAST in general performed more consistently across the sample and MRI modalities. The WMH volume change over 3 years obtained with MCMxxxVI with vs. without FSL-FAST BFC did not significantly differ (medians(IQR)(with BFC) = 3.2(6.3) vs. 2.9(7.4)ml (without BFC), p = 0.5), but both differed significantly from the WMH volume change obtained from subtracting post-processed FLAIR images (without BFC)(7.6(8.2)ml, p < 0.001). This latter method considerably inflated the WMH volume change as subtle WMH at baseline that became more intense at follow-up were counted as increase in the volumetric change. Measurement of WMH volume change remains

  17. Field Application of the Micro Biological Survey Method for a Simple and Effective Assessment of the Microbiological Quality of Water Sources in Developing Countries.

    Science.gov (United States)

    Arienzo, Alyexandra; Sobze, Martin Sanou; Wadoum, Raoul Emeric Guetiya; Losito, Francesca; Colizzi, Vittorio; Antonini, Giovanni

    2015-08-25

    According to the World Health Organization (WHO) guidelines, "safe drinking-water must not represent any significant risk to health over a lifetime of consumption, including different sensitivities that may occur between life stages". Traditional methods of water analysis are usually complex, time consuming and require an appropriately equipped laboratory, specialized personnel and expensive instrumentation. The aim of this work was to apply an alternative method, the Micro Biological Survey (MBS), to analyse for contaminants in drinking water. Preliminary experiments were carried out to demonstrate the linearity and accuracy of the MBS method and to verify the possibility of using the evaluation of total coliforms in 1 mL of water as a sufficient parameter to roughly though accurately determine water microbiological quality. The MBS method was then tested "on field" to assess the microbiological quality of water sources in the city of Douala (Cameroon, Central Africa). Analyses were performed on both dug and drilled wells in different periods of the year. Results confirm that the MBS method appears to be a valid and accurate method to evaluate the microbiological quality of many water sources and it can be of valuable aid in developing countries.

  18. Semiclassical methods in field theories

    International Nuclear Information System (INIS)

    Ventura, I.

    1978-10-01

    A new scheme is proposed for semi-classical quantization in field theory - the expansion about the charge (EAC) - which is developed within the canonical formalism. This method is suitable for quantizing theories that are invariant under global gauge transformations. It is used in the treatment of the non relativistic logarithmic theory that was proposed by Bialynicki-Birula and Mycielski - a theory we can formulate in any number of spatial dimensions. The non linear Schroedinger equation is also quantized by means of the EAC. The classical logarithmic theories - both, the non relativistic and the relativistic one - are studied in detail. It is shown that the Bohr-Sommerfeld quantization rule(BSQR) in field theory is, in many cases, equivalent to charge quantization. This rule is then applied to the massive Thirring Model and the logarithmic theories. The BSQR can be see as a simplified and non local version of the EAC [pt

  19. Human exposure assessment in the near field of GSM base-station antennas using a hybrid finite element/method of moments technique.

    Science.gov (United States)

    Meyer, Frans J C; Davidson, David B; Jakobus, Ulrich; Stuchly, Maria A

    2003-02-01

    A hybrid finite-element method (FEM)/method of moments (MoM) technique is employed for specific absorption rate (SAR) calculations in a human phantom in the near field of a typical group special mobile (GSM) base-station antenna. The MoM is used to model the metallic surfaces and wires of the base-station antenna, and the FEM is used to model the heterogeneous human phantom. The advantages of each of these frequency domain techniques are, thus, exploited, leading to a highly efficient and robust numerical method for addressing this type of bioelectromagnetic problem. The basic mathematical formulation of the hybrid technique is presented. This is followed by a discussion of important implementation details-in particular, the linear algebra routines for sparse, complex FEM matrices combined with dense MoM matrices. The implementation is validated by comparing results to MoM (surface equivalence principle implementation) and finite-difference time-domain (FDTD) solutions of human exposure problems. A comparison of the computational efficiency of the different techniques is presented. The FEM/MoM implementation is then used for whole-body and critical-organ SAR calculations in a phantom at different positions in the near field of a base-station antenna. This problem cannot, in general, be solved using the MoM or FDTD due to computational limitations. This paper shows that the specific hybrid FEM/MoM implementation is an efficient numerical tool for accurate assessment of human exposure in the near field of base-station antennas.

  20. A method for characterizing photon radiation fields

    International Nuclear Information System (INIS)

    Whicker, J.J.; Hsu, H.H.; Hsieh, F.H.; Borak, T.B.

    1999-01-01

    Uncertainty in dosimetric and exposure rate measurements can increase in areas where multi-directional and low-energy photons (< 100 keV) exist because of variations in energy and angular measurement response. Also, accurate measurement of external exposures in spatially non-uniform fields may require multiple dosimetry. Therefore, knowledge of the photon fields in the workplace is required for full understanding of the accuracy of dosimeters and instruments, and for determining the need for multiple dosimeters. This project was designed to develop methods to characterize photon radiation fields in the workplace, and to test the methods in a plutonium facility. The photon field at selected work locations was characterized using TLDs and a collimated NaI(Tl) detector from which spatial variations in photon energy distributions were calculated from measured spectra. Laboratory results showed the accuracy and utility of the method. Field measurement results combined with observed work patterns suggested the following: (1) workers are exposed from all directions, but not isotropically, (2) photon energy distributions were directionally dependent, (3) stuffing nearby gloves into the glovebox reduced exposure rates significantly, (4) dosimeter placement on the front of the chest provided for a reasonable estimate of the average dose equivalent to workers' torsos, (5) justifiable conclusions regarding the need for multiple dosimetry can be made using this quantitative method, and (6) measurements of the exposure rates with ionization chambers pointed with open beta windows toward the glovebox provided the highest measured rates, although absolute accuracy of the field measurements still needs to be assessed

  1. Assessing five field sampling methods to monitor Yellowstone National Park's northern ungulate winter range: the advantages and disadvantages of implementing a new sampling protocol

    Science.gov (United States)

    Pamela G. Sikkink; Roy Renkin; Geneva Chong; Art Sikkink

    2013-01-01

    The five field sampling methods tested for this study differed in richness and Simpson's Index values calculated from the raw data. How much the methods differed, and which ones were most similar to each other, depended on which diversity measure and which type of data were used for comparisons. When the number of species (richness) was used as a measure of...

  2. Efficient Training Methods for Conditional Random Fields

    National Research Council Canada - National Science Library

    Sutton, Charles A

    2008-01-01

    .... In this thesis, I investigate efficient training methods for conditional random fields with complex graphical structure, focusing on local methods which avoid propagating information globally along the graph...

  3. Apparatuses and methods for generating electric fields

    Science.gov (United States)

    Scott, Jill R; McJunkin, Timothy R; Tremblay, Paul L

    2013-08-06

    Apparatuses and methods relating to generating an electric field are disclosed. An electric field generator may include a semiconductive material configured in a physical shape substantially different from a shape of an electric field to be generated thereby. The electric field is generated when a voltage drop exists across the semiconductive material. A method for generating an electric field may include applying a voltage to a shaped semiconductive material to generate a complex, substantially nonlinear electric field. The shape of the complex, substantially nonlinear electric field may be configured for directing charged particles to a desired location. Other apparatuses and methods are disclosed.

  4. Validation of a standard field test method in four countries to assess the toxicity of residues in dung of cattle treated with veterinary medical products

    NARCIS (Netherlands)

    Floate, Kevin D.; Düring, Rolf Alexander; Hanafi, Jamal; Jud, Priska; Lahr, Joost; Lumaret, Jean Pierre; Scheffczyk, Adam; Tixier, Thomas; Wohde, Manuel; Römbke, Jörg; Sautot, Lucille; Blanckenhorn, Wolf U.

    2016-01-01

    Registration of veterinary medical products includes the provision that field tests may be required to assess potential nontarget effects associated with the excretion of product residues in dung of treated livestock (phase II, tier B testing). However, regulatory agencies provide no guidance on

  5. Validation of a Tablet Application for Assessing Dietary Intakes Compared with the Measured Food Intake/Food Waste Method in Military Personnel Consuming Field Rations

    Directory of Open Access Journals (Sweden)

    Mavra Ahmed

    2017-02-01

    Full Text Available The collection of accurate dietary intakes using traditional dietary assessment methods (e.g., food records from military personnel is challenging due to the demanding physiological and psychological conditions of training or operations. In addition, these methods are burdensome, time consuming, and prone to measurement errors. Adopting smart-phone/tablet technology could overcome some of these barriers. The objective was to assess the validity of a tablet app, modified to contain detailed nutritional composition data, in comparison to a measured food intake/waste method. A sample of Canadian Armed Forces personnel, randomized to either a tablet app (n = 9 or a weighed food record (wFR (n = 9, recorded the consumption of standard military rations for a total of 8 days. Compared to the gold standard measured food intake/waste method, the difference in mean energy intake was small (−73 kcal/day for tablet app and −108 kcal/day for wFR (p > 0.05. Repeated Measures Bland-Altman plots indicated good agreement for both methods (tablet app and wFR with the measured food intake/waste method. These findings demonstrate that the tablet app, with added nutritional composition data, is comparable to the traditional dietary assessment method (wFR and performs satisfactorily in relation to the measured food intake/waste method to assess energy, macronutrient, and selected micronutrient intakes in a sample of military personnel.

  6. Methods of thermal field theory

    Energy Technology Data Exchange (ETDEWEB)

    Mallik, S [Saha Institute of Nuclear Physics, Calcutta (India)

    1998-11-01

    We introduce the basic ideas of thermal field theory and review its path integral formulation. We then discuss the problems of QCD theory at high and at low temperatures. At high temperature the naive perturbation expansion breaks down and is cured by resummation. We illustrate this improved perturbation expansion with the g{sup 2}{phi}{sup 4} theory and then sketch its application to find the gluon damping rate in QCD theory. At low temperature the hadronic phase is described systematically by the chiral perturbation theory. The results obtained from this theory for the quark and the gluon condensates are discussed. (author) 22 refs., 6 figs.

  7. Formal Method of Description Supporting Portfolio Assessment

    Science.gov (United States)

    Morimoto, Yasuhiko; Ueno, Maomi; Kikukawa, Isao; Yokoyama, Setsuo; Miyadera, Youzou

    2006-01-01

    Teachers need to assess learner portfolios in the field of education. However, they need support in the process of designing and practicing what kind of portfolios are to be assessed. To solve the problem, a formal method of describing the relations between the lesson forms and portfolios that need to be collected and the relations between…

  8. Information System Quality Assessment Methods

    OpenAIRE

    Korn, Alexandra

    2014-01-01

    This thesis explores challenging topic of information system quality assessment and mainly process assessment. In this work the term Information System Quality is defined as well as different approaches in a quality definition for different domains of information systems are outlined. Main methods of process assessment are overviewed and their relationships are described. Process assessment methods are divided into two categories: ISO standards and best practices. The main objective of this w...

  9. Methods of risk assessment

    International Nuclear Information System (INIS)

    Jones, D.R.

    1981-01-01

    The subject is discussed under the headings: introduction (identification, quantification of risk); some approaches to risk evaluation (use of the 'no risk' principle; the 'acceptable risk' method; risk balancing; comparison of risks, benefits and other costs); cost benefit analysis; an alternative approach (tabulation and display; description and reduction of the data table); identification of potential decision sets consistent with the constraints. Some references are made to nuclear power. (U.K.)

  10. Introduction to the background field method

    International Nuclear Information System (INIS)

    Abbott, L.F.; Brandeis Univ., Waltham, MA

    1982-01-01

    The background field approach to calculations in gauge field theories is presented. Conventional functional techniques are reviewed and the background field method is introduced. Feynman rules and renormalization are discussed and, as an example, the Yang-Mills β function is computed. (author)

  11. Historic Methods for Capturing Magnetic Field Images

    Science.gov (United States)

    Kwan, Alistair

    2016-01-01

    I investigated two late 19th-century methods for capturing magnetic field images from iron filings for historical insight into the pedagogy of hands-on physics education methods, and to flesh out teaching and learning practicalities tacit in the historical record. Both methods offer opportunities for close sensory engagement in data-collection…

  12. Computational methods for reversed-field equilibrium

    International Nuclear Information System (INIS)

    Boyd, J.K.; Auerbach, S.P.; Willmann, P.A.; Berk, H.L.; McNamara, B.

    1980-01-01

    Investigating the temporal evolution of reversed-field equilibrium caused by transport processes requires the solution of the Grad-Shafranov equation and computation of field-line-averaged quantities. The technique for field-line averaging and the computation of the Grad-Shafranov equation are presented. Application of Green's function to specify the Grad-Shafranov equation boundary condition is discussed. Hill's vortex formulas used to verify certain computations are detailed. Use of computer software to implement computational methods is described

  13. Geostatistical methods applied to field model residuals

    DEFF Research Database (Denmark)

    Maule, Fox; Mosegaard, K.; Olsen, Nils

    consists of measurement errors and unmodelled signal), and is typically assumed to be uncorrelated and Gaussian distributed. We have applied geostatistical methods to analyse the residuals of the Oersted(09d/04) field model [http://www.dsri.dk/Oersted/Field_models/IGRF_2005_candidates/], which is based...

  14. Teaching Geographic Field Methods Using Paleoecology

    Science.gov (United States)

    Walsh, Megan K.

    2014-01-01

    Field-based undergraduate geography courses provide numerous pedagogical benefits including an opportunity for students to acquire employable skills in an applied context. This article presents one unique approach to teaching geographic field methods using paleoecological research. The goals of this course are to teach students key geographic…

  15. Electromagnetic field computation by network methods

    CERN Document Server

    Felsen, Leopold B; Russer, Peter

    2009-01-01

    This monograph proposes a systematic and rigorous treatment of electromagnetic field representations in complex structures. The book presents new strong models by combining important computational methods. This is the last book of the late Leopold Felsen.

  16. Low-frequency fields - health risk assessment

    International Nuclear Information System (INIS)

    Bernhardt, J.

    1993-01-01

    The author briefly reviews the biological actions and effects of low-frequency fields, epidemiological studies and discusses health risks in detail. He describes the assessment principles of the International Commission on Non-ionizing Radiation Protection (ICNIRP), medical principles for risk assessment, determination of limits and thesholds, and aspects of prevention. This is supplemented to by several fables and literature list. (Uhe) [de

  17. Nickel quantification in serum by a validated sector-field inductively coupled plasma mass spectrometry method: Assessment of tentative reference values for an Italian population.

    Science.gov (United States)

    Bocca, Beatrice; Forte, Giovanni; Ronchi, Anna; Gaggeri, Raffaella; Alimonti, Alessandro; Minoia, Claudio

    2006-01-01

    The daily exposure to Ni from food, industrial processes, jewellery and coins makes the determination of Ni in human serum an important way to monitor the health status in non-occupationally exposed subjects. To this end, a method based on sector-field inductively coupled plasma mass spectrometry was developed and validated. The limits of detection (LoD) and quantification (LoQ), sensitivity, linearity range, trueness, repeatability, within-laboratory reproducibility and robustness were the considered issues of the validation process. The uncertainty associated with the measurements was also calculated, according to the Eurachem/Citac Guide. The method LoD and LoQ were 0.03 and 0.09 ng mL(-1), linearity was over two order of magnitude, trueness was -3.57%, and the repeatability and reproducibility showed relative standard deviations equal to 4.56% and 6.52%, respectively. The relative expanded uncertainty was 21.8% at the Ni levels found in the general population. The tentative reference value for serum Ni was 0.466 +/- 0.160 ng mL(-1) with a related interval between 0.226 and 1.026 ng mL(-1). Copyright 2006 John Wiley & Sons, Ltd.

  18. Method of valuation of water field capacity

    International Nuclear Information System (INIS)

    Dancette, C.; Maertens, C.

    1973-01-01

    A method allowing the obtention of an approximation of field capacity, with only the determination of water retention at pF=3, is described. In alluvial soils, the accuracy of this method appears sufficient to satisfy the current needs in agriculture problems [fr

  19. Compressible cavitation with stochastic field method

    Science.gov (United States)

    Class, Andreas; Dumond, Julien

    2012-11-01

    Non-linear phenomena can often be well described using probability density functions (pdf) and pdf transport models. Traditionally the simulation of pdf transport requires Monte-Carlo codes based on Lagrange particles or prescribed pdf assumptions including binning techniques. Recently, in the field of combustion, a novel formulation called the stochastic field method solving pdf transport based on Euler fields has been proposed which eliminates the necessity to mix Euler and Lagrange techniques or prescribed pdf assumptions. In the present work, part of the PhD Design and analysis of a Passive Outflow Reducer relying on cavitation, a first application of the stochastic field method to multi-phase flow and in particular to cavitating flow is presented. The application considered is a nozzle subjected to high velocity flow so that sheet cavitation is observed near the nozzle surface in the divergent section. It is demonstrated that the stochastic field formulation captures the wide range of pdf shapes present at different locations. The method is compatible with finite-volume codes where all existing physical models available for Lagrange techniques, presumed pdf or binning methods can be easily extended to the stochastic field formulation.

  20. Methods of sperm vitality assessment.

    Science.gov (United States)

    Moskovtsev, Sergey I; Librach, Clifford L

    2013-01-01

    Sperm vitality is a reflection of the proportion of live, membrane-intact spermatozoa determined by either dye exclusion or osmoregulatory capacity under hypo-osmotic conditions. In this chapter we address the two most common methods of sperm vitality assessment: eosin-nigrosin staining and the hypo-osmotic swelling test, both utilized in clinical Andrology laboratories.

  1. A new NaI(Tl) four-detector layout for field contamination assessment using artificial neural networks and the Monte Carlo method for system calibration

    International Nuclear Information System (INIS)

    Moreira, M.C.F.; Conti, C.C.; Schirru, R.

    2010-01-01

    An NaI(Tl) multidetector layout combined with the use of Monte Carlo (MC) calculations and artificial neural networks(ANN) is proposed to assess the radioactive contamination of urban and semi-urban environment surfaces. A very simple urban environment like a model street composed of a wall on either side and the ground surface was the study case. A layout of four NaI(Tl) detectors was used, and the data corresponding to the response of the detectors were obtained by the Monte Carlo method. Two additional data sets with random values for the contamination and for detectors' response were also produced to test the ANNs. For this work, 18 feedforward topologies with backpropagation learning algorithm ANNs were chosen and trained. The results showed that some trained ANNs were able to accurately predict the contamination on the three urban surfaces when submitted to values within the training range. Other results showed that generalization outside the training range of values could not be achieved. The use of Monte Carlo calculations in combination with ANNs has been proven to be a powerful tool to perform detection calibration for highly complicated detection geometries.

  2. A new NaI(Tl) four-detector layout for field contamination assessment using artificial neural networks and the Monte Carlo method for system calibration

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, M.C.F., E-mail: marcos@ird.gov.b [Universidade Federal do Rio de Janeiro, COPPE, Programa de Engenharia Nuclear, Laboratorio de Monitoracao de Processos (Federal University of Rio de Janeiro, COPPE, Nuclear Engineering Program, Process Monitoring Laboratory), P.O. Box 68509, 21941-972 Rio de Janeiro (Brazil); Instituto de Radioprotecao e Dosimetria, CNEN/IRD (Radiation Protection and Dosimetry Institute, CNEN/IRD), Av. Salvador Allende s/no, P.O. Box 37750, 22780-160 Rio de Janeiro (Brazil); Conti, C.C. [Instituto de Radioprotecao e Dosimetria, CNEN/IRD (Radiation Protection and Dosimetry Institute, CNEN/IRD), Av. Salvador Allende s/no, P.O. Box 37750, 22780-160 Rio de Janeiro (Brazil); Schirru, R. [Universidade Federal do Rio de Janeiro, COPPE, Programa de Engenharia Nuclear, Laboratorio de Monitoracao de Processos (Federal University of Rio de Janeiro, COPPE, Nuclear Engineering Program, Process Monitoring Laboratory), P.O. Box 68509, 21941-972 Rio de Janeiro (Brazil)

    2010-09-21

    An NaI(Tl) multidetector layout combined with the use of Monte Carlo (MC) calculations and artificial neural networks(ANN) is proposed to assess the radioactive contamination of urban and semi-urban environment surfaces. A very simple urban environment like a model street composed of a wall on either side and the ground surface was the study case. A layout of four NaI(Tl) detectors was used, and the data corresponding to the response of the detectors were obtained by the Monte Carlo method. Two additional data sets with random values for the contamination and for detectors' response were also produced to test the ANNs. For this work, 18 feedforward topologies with backpropagation learning algorithm ANNs were chosen and trained. The results showed that some trained ANNs were able to accurately predict the contamination on the three urban surfaces when submitted to values within the training range. Other results showed that generalization outside the training range of values could not be achieved. The use of Monte Carlo calculations in combination with ANNs has been proven to be a powerful tool to perform detection calibration for highly complicated detection geometries.

  3. Development, Validation, and Interlaboratory Evaluation of a Quantitative Multiplexing Method To Assess Levels of Ten Endogenous Allergens in Soybean Seed and Its Application to Field Trials Spanning Three Growing Seasons.

    Science.gov (United States)

    Hill, Ryan C; Oman, Trent J; Wang, Xiujuan; Shan, Guomin; Schafer, Barry; Herman, Rod A; Tobias, Rowel; Shippar, Jeff; Malayappan, Bhaskar; Sheng, Li; Xu, Austin; Bradshaw, Jason

    2017-07-12

    As part of the regulatory approval process in Europe, comparison of endogenous soybean allergen levels between genetically engineered (GE) and non-GE plants has been requested. A quantitative multiplex analytical method using tandem mass spectrometry was developed and validated to measure 10 potential soybean allergens from soybean seed. The analytical method was implemented at six laboratories to demonstrate the robustness of the method and further applied to three soybean field studies across multiple growing seasons (including 21 non-GE soybean varieties) to assess the natural variation of allergen levels. The results show environmental factors contribute more than genetic factors to the large variation in allergen abundance (2- to 50-fold between environmental replicates) as well as a large contribution of Gly m 5 and Gly m 6 to the total allergen profile, calling into question the scientific rational for measurement of endogenous allergen levels between GE and non-GE varieties in the safety assessment.

  4. General Plan Environmental Assessment, Hurlburt Field, Florida

    Science.gov (United States)

    2005-10-01

    sebiferum) and cogon grass (Imperata Resource/Issue Areas Hurlburt Field General Plan Environmental Assessment 4-9 cylindrica) are most...habitat on the western portion of the installation. The restoration of a native long-leaf pine/wire grass community on Hurlburt is associated with a

  5. Method of Relating Grain Size Distribution to Hydraulic Conductivity in Dune Sands to Assist in Assessing Managed Aquifer Recharge Projects: Wadi Khulays Dune Field, Western Saudi Arabia

    KAUST Repository

    Lopez Valencia, Oliver Miguel; Jadoon, Khan; Missimer, Thomas

    2015-01-01

    Planning for use of a dune field aquifer for managed aquifer recharge (MAR) requires that hydraulic properties need to be estimated over a large geographic area. Saturated hydraulic conductivity of dune sands is commonly estimated from grain size

  6. Eigenstates with the auxiliary field method

    Energy Technology Data Exchange (ETDEWEB)

    Semay, Claude [Service de Physique Nucleaire et Subnucleaire, Universite de Mons-UMONS, 20 Place du Parc, 7000 Mons (Belgium); Silvestre-Brac, Bernard, E-mail: claude.semay@umons.ac.b, E-mail: silvestre@lpsc.in2p3.f [LPSC Universite Joseph Fourier, Grenoble 1, CNRS/IN2P3, Institut Polytechnique de Grenoble, Avenue des Martyrs 53, F-38026 Grenoble-Cedex (France)

    2010-07-02

    The auxiliary field method is a powerful technique to obtain approximate closed-form energy formulas for eigenequations in quantum mechanics. Very good results can be obtained for Schroedinger and semirelativistic Hamiltonians with various potentials, even in the case of many-body problems. This method can also provide approximate eigenstates in terms of well-known wavefunctions, for instance harmonic oscillator or hydrogen-like states, but with a characteristic size which depends on quantum numbers. In this paper, we consider two-body Schroedinger equations with linear, logarithmic and exponential potentials and show that analytical approximations of the corresponding eigenstates can be obtained with the auxiliary field method, with very good accuracy in some cases.

  7. Eigenstates with the auxiliary field method

    International Nuclear Information System (INIS)

    Semay, Claude; Silvestre-Brac, Bernard

    2010-01-01

    The auxiliary field method is a powerful technique to obtain approximate closed-form energy formulas for eigenequations in quantum mechanics. Very good results can be obtained for Schroedinger and semirelativistic Hamiltonians with various potentials, even in the case of many-body problems. This method can also provide approximate eigenstates in terms of well-known wavefunctions, for instance harmonic oscillator or hydrogen-like states, but with a characteristic size which depends on quantum numbers. In this paper, we consider two-body Schroedinger equations with linear, logarithmic and exponential potentials and show that analytical approximations of the corresponding eigenstates can be obtained with the auxiliary field method, with very good accuracy in some cases.

  8. Electric Field Quantitative Measurement System and Method

    Science.gov (United States)

    Generazio, Edward R. (Inventor)

    2016-01-01

    A method and system are provided for making a quantitative measurement of an electric field. A plurality of antennas separated from one another by known distances are arrayed in a region that extends in at least one dimension. A voltage difference between at least one selected pair of antennas is measured. Each voltage difference is divided by the known distance associated with the selected pair of antennas corresponding thereto to generate a resulting quantity. The plurality of resulting quantities defined over the region quantitatively describe an electric field therein.

  9. Field test of a new Australian method of rangeland monitoring

    Science.gov (United States)

    Suzanne Mayne; Neil West

    2001-01-01

    Managers need more efficient means of monitoring changes on the lands they manage. Accordingly, a new Australian approach was field tested and compared to the Daubenmire method of assessing plant cover, litter, and bare soil. The study area was a 2 mile wide by 30.15 mile long strip, mostly covered by salt desert shrub ecosystem types, centered along the SE boundary of...

  10. Assessment of a landfill methane emission screening method using an unmanned aerial vehicle mounted thermal infrared camera – A field study

    DEFF Research Database (Denmark)

    Fjelsted, Lotte; Christensen, A. G.; Larsen, J. E.

    2018-01-01

    An unmanned aerial vehicle (UAV)-mounted thermal infrared (TIR) camera’s ability to delineate landfill gas (LFG) emission hotspots was evaluated in a field test at two Danish landfills (Hedeland landfill and Audebo landfill). At both sites, a test area of 100 m2 was established and divided into a...

  11. Spectral methods in quantum field theory

    International Nuclear Information System (INIS)

    Graham, Noah; Quandt, Markus; Weigel, Herbert

    2009-01-01

    This concise text introduces techniques from quantum mechanics, especially scattering theory, to compute the effects of an external background on a quantum field in general, and on the properties of the quantum vacuum in particular. This approach can be succesfully used in an increasingly large number of situations, ranging from the study of solitons in field theory and cosmology to the determination of Casimir forces in nano-technology. The method introduced and applied in this book is shown to give an unambiguous connection to perturbation theory, implementing standard renormalization conditions even for non-perturbative backgrounds. It both gives new theoretical insights, for example illuminating longstanding questions regarding Casimir stresses, and also provides an efficient analytic and numerical tool well suited to practical calculations. Last but not least, it elucidates in a concrete context many of the subtleties of quantum field theory, such as divergences, regularization and renormalization, by connecting them to more familiar results in quantum mechanics. While addressed primarily at young researchers entering the field and nonspecialist researchers with backgrounds in theoretical and mathematical physics, introductory chapters on the theoretical aspects of the method make the book self-contained and thus suitable for advanced graduate students. (orig.)

  12. Renormalization using the background-field method

    International Nuclear Information System (INIS)

    Ichinose, S.; Omote, M.

    1982-01-01

    Renormalization using the background-field method is examined in detail. The subtraction mechanism of subdivergences is described with reference to multi-loop diagrams and one- and two-loop counter-term formulae are explicitly given. The original one-loop counter-term formula of 't Hooft is thereby improved. The present method of renormalization is far easier to manage than the usual one owing to the fact only gauge-invariant quantities are to be considered when worked in an appropriate gauge. Gravity and Yang-Mills theories are studied as examples. (orig.)

  13. On - Site Assessment Methods For Environmental Radioactivity

    International Nuclear Information System (INIS)

    Petrinec, B.; Babic, D.; Bituh, T.

    2015-01-01

    A method for the rapid determination of radioactivity in cases of release into the environment as well as in cases of nuclear/radiological accidents is described. These measurements would enable a direct risk assessment for humans and biota, without any sampling and at a considerably larger number of locations than in previous studies. Thus obtained, the substantially expanded dataset is expected to shed more light on the properties of environmental radioactivity both in the region studied and in other similar areas. Field measurements will be performed and samples of soil and biota will be collected in order to compare field results with laboratory measurements. Once the method has been validated, previously unexplored locations will be included in the study. Our measurements at numerous locations will also provide control values for comparison in cases of any unplanned or accidental radiological event. An assessment of the possible effects of radionuclide concentrations on the human food chain and biota will be performed within the appropriate models used worldwide exactly for this purpose. In this way, the project should contribute to regional, European, and global efforts towards understanding the radiological impact on ecosystems. Field measurements will also address certain issues in the environmental metrology of radioactive substances, e.g., simultaneous determination of activity concentrations and related dose rates. This will serve as a tool for rapid risk assessment in emergency situations. (author).

  14. Method of Relating Grain Size Distribution to Hydraulic Conductivity in Dune Sands to Assist in Assessing Managed Aquifer Recharge Projects: Wadi Khulays Dune Field, Western Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Oliver M. Lopez

    2015-11-01

    Full Text Available Planning for use of a dune field aquifer for managed aquifer recharge (MAR requires that hydraulic properties need to be estimated over a large geographic area. Saturated hydraulic conductivity of dune sands is commonly estimated from grain size distribution data by employing some type of empirical equation. Over 50 samples from the Wadi Khulays dune field in Western Saudi Arabia were collected and the grain size distribution, porosity, and hydraulic conductivity were measured. An evaluation of 20 existing empirical equations showed a generally high degree of error in the predicted compared to the measured hydraulic conductivity values of these samples. Statistical analyses comparing estimated versus measured hydraulic conductivity demonstrated that there is a significant relationship between hydraulic conductivity and mud percentage (and skewness. The modified Beyer equation, which showed a generally low prediction error, was modified by adding a second term fitting parameter related to the mud concentration based on 25 of the 50 samples analyzed. An inverse optimization process was conducted to quantify the fitting parameter and a new empirical equation was developed. This equation was tested against the remaining 25 samples analyzed and produced an estimated saturated hydraulic conductivity with the lowest error of any empirical equation. This methodology can be used for large dune field hydraulic conductivity estimation and reduce planning costs for MAR systems.

  15. Method of Relating Grain Size Distribution to Hydraulic Conductivity in Dune Sands to Assist in Assessing Managed Aquifer Recharge Projects: Wadi Khulays Dune Field, Western Saudi Arabia

    KAUST Repository

    Lopez Valencia, Oliver Miguel

    2015-11-12

    Planning for use of a dune field aquifer for managed aquifer recharge (MAR) requires that hydraulic properties need to be estimated over a large geographic area. Saturated hydraulic conductivity of dune sands is commonly estimated from grain size distribution data by employing some type of empirical equation. Over 50 samples from the Wadi Khulays dune field in Western Saudi Arabia were collected and the grain size distribution, porosity, and hydraulic conductivity were measured. An evaluation of 20 existing empirical equations showed a generally high degree of error in the predicted compared to the measured hydraulic conductivity values of these samples. Statistical analyses comparing estimated versus measured hydraulic conductivity demonstrated that there is a significant relationship between hydraulic conductivity and mud percentage (and skewness). The modified Beyer equation, which showed a generally low prediction error, was modified by adding a second term fitting parameter related to the mud concentration based on 25 of the 50 samples analyzed. An inverse optimization process was conducted to quantify the fitting parameter and a new empirical equation was developed. This equation was tested against the remaining 25 samples analyzed and produced an estimated saturated hydraulic conductivity with the lowest error of any empirical equation. This methodology can be used for large dune field hydraulic conductivity estimation and reduce planning costs for MAR systems.

  16. LNG Safety Assessment Evaluation Methods

    Energy Technology Data Exchange (ETDEWEB)

    Muna, Alice Baca [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); LaFleur, Angela Christine [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-05-01

    Sandia National Laboratories evaluated published safety assessment methods across a variety of industries including Liquefied Natural Gas (LNG), hydrogen, land and marine transportation, as well as the US Department of Defense (DOD). All the methods were evaluated for their potential applicability for use in the LNG railroad application. After reviewing the documents included in this report, as well as others not included because of repetition, the Department of Energy (DOE) Hydrogen Safety Plan Checklist is most suitable to be adapted to the LNG railroad application. This report was developed to survey industries related to rail transportation for methodologies and tools that can be used by the FRA to review and evaluate safety assessments submitted by the railroad industry as a part of their implementation plans for liquefied or compressed natural gas storage ( on-board or tender) and engine fueling delivery systems. The main sections of this report provide an overview of various methods found during this survey. In most cases, the reference document is quoted directly. The final section provides discussion and a recommendation for the most appropriate methodology that will allow efficient and consistent evaluations to be made. The DOE Hydrogen Safety Plan Checklist was then revised to adapt it as a methodology for the Federal Railroad Administration’s use in evaluating safety plans submitted by the railroad industry.

  17. Advanced methods of fatigue assessment

    CERN Document Server

    Radaj, Dieter

    2013-01-01

    The book in hand presents advanced methods of brittle fracture and fatigue assessment. The Neuber concept of fictitious notch rounding is enhanced with regard to theory and application. The stress intensity factor concept for cracks is extended to pointed and rounded corner notches as well as to locally elastic-plastic material behaviour. The averaged strain energy density within a circular sector volume around the notch tip is shown to be suitable for strength-assessments. Finally, the various implications of cyclic plasticity on fatigue crack growth are explained with emphasis being laid on the DJ-integral approach.   This book continues the expositions of the authors’ well known reference work in German language ‘Ermüdungsfestigkeit – Grundlagen für Ingenieure’ (Fatigue strength – fundamentals for engineers).

  18. Improved power performance assessment methods

    Energy Technology Data Exchange (ETDEWEB)

    Frandsen, S; Antoniou, I; Dahlberg, J A [and others

    1999-03-01

    The uncertainty of presently-used methods for retrospective assessment of the productive capacity of wind farms is unacceptably large. The possibilities of improving the accuracy have been investigated and are reported. A method is presented that includes an extended power curve and site calibration. In addition, blockage effects with respect to reference wind speed measurements are analysed. It is found that significant accuracy improvements are possible by the introduction of more input variables such as turbulence and wind shear, in addition to mean wind speed and air density. Also, the testing of several or all machines in the wind farm - instead of only one or two - may provide a better estimate of the average performance. (au)

  19. Accuracy limits of the equivalent field method for irregular photon fields

    International Nuclear Information System (INIS)

    Sanz, Dario Esteban

    2002-01-01

    A mathematical approach is developed to evaluate the accuracy of the equivalent field method using basic clinical photon beam data. This paper presents an analytical calculation of dose errors arising when field equivalencies, calculated at a certain reference depth, are translated to other depths. The phantom scatter summation is expressed as a Riemann-Stieltjes integral and two categories of irregular fields are introduced: uniform and multiform. It is shown that multiform fields produce errors whose magnitudes are nearly twice those corresponding to uniform fields in extreme situations. For uniform field shapes, the maximum, local, relative dose errors, when the equivalencies are calculated at 10 cm depth on the central axis and translated to a depth of 30 cm, are 3.8% and 8.8% for 6 MV and cobalt-60 photon beams, respectively. In terms of maximum dose those errors are within 1-2%. This supports the conclusion that the equivalencies between rectangular fields, which are examples of uniform fields, are applicable to dose ratio functions irrespective of beam energy. However, the magnitude of such errors could be of importance when assessing the exit dose for in vivo monitoring. This work provides a better understanding of the influence of the irregular field shapes on the accuracy of the equivalent field method. (author)

  20. Relaxation methods for gauge field equilibrium equations

    International Nuclear Information System (INIS)

    Adler, S.L.; Piran, T.

    1984-01-01

    This article gives a pedagogical introduction to relaxation methods for the numerical solution of elliptic partial differential equations, with particular emphasis on treating nonlinear problems with delta-function source terms and axial symmetry, which arise in the context of effective Lagrangian approximations to the dynamics of quantized gauge fields. The authors present a detailed theoretical analysis of three models which are used as numerical examples: the classical Abelian Higgs model (illustrating charge screening), the semiclassical leading logarithm model (illustrating flux confinement within a free boundary or ''bag''), and the axially symmetric Bogomol'nyi-Prasad-Sommerfield monopoles (illustrating the occurrence of p topological quantum numbers in non-Abelian gauge fields). They then proceed to a self-contained introduction to the theory of relaxation methods and allied iterative numerical methods and to the practical aspects of their implementation, with attention to general issues which arise in the three examples. The authors conclude with a brief discussion of details of the numerical solution of the models, presenting sample numerical results

  1. Standard Operating Procedures and Field Methods Used for Conducting Ecological Risk Assessment Case Studies. Naval Construction Battalion Center, Davisville, Rhode Island, and Naval Shipyard, Portsmouth, Kittery, Maine.

    Science.gov (United States)

    1992-05-01

    Studies by Craig et al. 20 have chloride extraction/Grignard derivatization method. shown that significant evaporative losses of TBT + Methylene...and Craig . P1J Anahiw. 1987. 112: 1781 available from IEEE Service Center. 445 Hoes tLane. 21/ Aue. W A and Flinn. C G J Cltroinato-er.. 1977, 142 145...Environmental Research Laboratory Narragansett, Narragansett, RI. Keith, L.H., W. Crummett, J. Deegan , Jr, R.A. Libby, J.K. Taylor, and B. Wentler, 1983. Annal

  2. Assessment of microorganisms from Indonesian Oil Fields

    Energy Technology Data Exchange (ETDEWEB)

    Kadarwati, S.; Udiharto, M.; Rahman, M.; Jasjfi, E.; Legowo, E.H. [Research and Development Centre for Oil and Gas Technology LEMIGAS, Jakarta Selatan (Indonesia)

    1995-12-31

    Petroleum resources have been the mainstay of the national development in Indonesia. However, resources are being depleted after over a century of exploitation, while the demand continues to grow with the rapid economic development of the country. In facing the problem, EOR has been applied in Indonesia, such as the steamflooding project in Duri field, but a more energy efficient technology would be preferable. Therefore, MEOR has been recommended as a promising solution. Our study, aimed at finding indigenous microorganisms which can be developed for application in MEOR, has isolated microbes from some oil fields of Indonesia. These microorganisms have been identified, their activities studied, and the effects of their metabolisms examined. This paper describes the research carried out by LEMIGAS in this respect, giving details on the methods of sampling, incubation, identification, and activation of the microbes as well as tests on the effects of their metabolites, with particular attention to those with potential for application in MEOR.

  3. Narrow field electromagnetic sensor system and method

    International Nuclear Information System (INIS)

    McEwan, T.E.

    1996-01-01

    A narrow field electromagnetic sensor system and method of sensing a characteristic of an object provide the capability to realize a characteristic of an object such as density, thickness, or presence, for any desired coordinate position on the object. One application is imaging. The sensor can also be used as an obstruction detector or an electronic trip wire with a narrow field without the disadvantages of impaired performance when exposed to dirt, snow, rain, or sunlight. The sensor employs a transmitter for transmitting a sequence of electromagnetic signals in response to a transmit timing signal, a receiver for sampling only the initial direct RF path of the electromagnetic signal while excluding all other electromagnetic signals in response to a receive timing signal, and a signal processor for processing the sampled direct RF path electromagnetic signal and providing an indication of the characteristic of an object. Usually, the electromagnetic signal is a short RF burst and the obstruction must provide a substantially complete eclipse of the direct RF path. By employing time-of-flight techniques, a timing circuit controls the receiver to sample only the initial direct RF path of the electromagnetic signal while not sampling indirect path electromagnetic signals. The sensor system also incorporates circuitry for ultra-wideband spread spectrum operation that reduces interference to and from other RF services while allowing co-location of multiple electronic sensors without the need for frequency assignments. 12 figs

  4. Testing an Automated Accuracy Assessment Method on Bibliographic Data

    Directory of Open Access Journals (Sweden)

    Marlies Olensky

    2014-12-01

    Full Text Available This study investigates automated data accuracy assessment as described in data quality literature for its suitability to assess bibliographic data. The data samples comprise the publications of two Nobel Prize winners in the field of Chemistry for a 10-year-publication period retrieved from the two bibliometric data sources, Web of Science and Scopus. The bibliographic records are assessed against the original publication (gold standard and an automatic assessment method is compared to a manual one. The results show that the manual assessment method reflects truer accuracy scores. The automated assessment method would need to be extended by additional rules that reflect specific characteristics of bibliographic data. Both data sources had higher accuracy scores per field than accumulated per record. This study contributes to the research on finding a standardized assessment method of bibliographic data accuracy as well as defining the impact of data accuracy on the citation matching process.

  5. Mathematical methods in geometrization of coal field

    Science.gov (United States)

    Shurygin, D. N.; Kalinchenko, V. M.; Tkachev, V. A.; Tretyak, A. Ya

    2017-10-01

    In the work, the approach to increase overall performance of collieries on the basis of an increase in accuracy of geometrization of coal thicknesses is considered. The sequence of stages of mathematical modelling of spatial placing of indicators of a deposit taking into account allocation of homogeneous sites of thickness and an establishment of quantitative interrelations between mountain-geological indicators of coal layers is offered. As a uniform mathematical method for modelling of various interrelations, it is offered to use a method of the group accounting of arguments (MGUA), one of versions of the regressive analysis. This approach can find application during delimitation between geological homogeneous sites of coal thicknesses in the form of a linear discriminant function. By an example of division into districts of a mine field in the conditions of mine “Sadkinsky” (East Donbass), the use of the complex approach for forecasting of zones of the small amplitude of disturbance of a coal layer on the basis of the discriminant analysis and MGUA is shown.

  6. Methods of geodiversity assessment and theirs application

    Science.gov (United States)

    Zwoliński, Zbigniew; Najwer, Alicja; Giardino, Marco

    2016-04-01

    environment is based on geodiversity indexes. Burnett et al. (1998) and Nichols et al. (1998) used Shanon-Weaver diversity index but without success. Most studies that use geodiversity indexes are based on a concept originally published by Serrano, Ruiz-Flaño (2007), later developed by others, e.g. Serrano et al. (2009), Hjort, Luoto (2010), Pellitero et al. (2010, 2014), Comanescu, Nedelea (2012), Kot (2012), Silva et al. (2013), Martinez-Grana et al. 2015). Geodiversity value can also be assessed using techniques of quantitative and qualitative point bonitation method and its modifications (Kot 2005 a, b, c, 2006 a, b, 2014, Jačková, Romportl 2008, Kot, Smidt 2010, Zwoliński, Stachowiak 2012, Pereira et al. 2013). Highly promising results of the geodiversity assessments may also provide statistical modeling, more precisely generalized additive models (GAM) (Hjort, Luoto 2012, Hjort et al. 2012). Methods of geodiversity assessment may be recognised as direct and indirect (Pellitero et al. 2014). Direct methods are used to geodiversity value computation of soils, rocks, types of landforms, etc. Their application allows to obtain more accurate results and the same calculation is much simpler, although their usage is much more labor intensive (Pellitero et al. 2014), and often considerably more expensive. The use of these indicators for the assessment of broad scale areas is quite breakneck and their universality due to the fact limited. Indirect methods are not identifying features internally different, but some favorable conditions for the occurrence and intensification of the processes that usually generate diversity of the abiotic components and consequently the landforms. The biggest advantage of using indirect methods is time and money saving, resulting from the reduction to the minimum of field work. Usually source data acquisition (satellite imagery, digital elevation models or point clouds) is as well much cheaper, but unfortunately their correct preprocessing and

  7. Efficient Calculation of Near Fields in the FDTD Method

    DEFF Research Database (Denmark)

    Franek, Ondrej

    2011-01-01

    When calculating frequency-domain near fields by the FDTD method, almost 50 % reduction in memory and CPU operations can be achieved if only E-fields are stored during the main time-stepping loop and H-fields computed later. An improved method of obtaining the H-fields from Faraday's Law is prese...

  8. PHASE GRADIENT METHOD OF MAGNETIC FIELD MEASUREMENTS IN ELECTRIC VEHICLES

    Directory of Open Access Journals (Sweden)

    N. G. Ptitsyna

    2013-01-01

    Full Text Available Operation of electric and hybrid vehicles demands real time magnetic field control, for instance, for fire and electromagnetic safety. The article deals with a method of magnetic field measurements onboard electric cars taking into account peculiar features of these fields. The method is based on differential methods of measurements, and minimizes the quantity of magnetic sensors.

  9. Axial Field Electric Motor and Method

    National Research Council Canada - National Science Library

    Cho, Chahee P

    2007-01-01

    .... A hybrid field, brushless, permanent magnet electric motor utilizing a rotor with two sets of permanent magnets oriented such that the flux produced by the two sets of magnets is perpendicular to each...

  10. Magnetic field transfer device and method

    Science.gov (United States)

    Wipf, S.L.

    1990-02-13

    A magnetic field transfer device includes a pair of oppositely wound inner coils which each include at least one winding around an inner coil axis, and an outer coil which includes at least one winding around an outer coil axis. The windings may be formed of superconductors. The axes of the two inner coils are parallel and laterally spaced from each other so that the inner coils are positioned in side-by-side relation. The outer coil is outwardly positioned from the inner coils and rotatable relative to the inner coils about a rotational axis substantially perpendicular to the inner coil axes to generate a hypothetical surface which substantially encloses the inner coils. The outer coil rotates relative to the inner coils between a first position in which the outer coil axis is substantially parallel to the inner coil axes and the outer coil augments the magnetic field formed in one of the inner coils, and a second position 180[degree] from the first position, in which the augmented magnetic field is transferred into the other inner coil and reoriented 180[degree] from the original magnetic field. The magnetic field transfer device allows a magnetic field to be transferred between volumes with negligible work being required to rotate the outer coil with respect to the inner coils. 16 figs.

  11. Field theoretical methods in chemical physics

    International Nuclear Information System (INIS)

    Paul, R.

    1982-01-01

    Field theory will become an important tool for the chemist, and this book presents a clear and thorough account of the theory itself and its applications for solving a wide variety of chemical problems. The author has brought together the foundations upon which the many and varied applications of field theory have been built, giving more intermediate steps than is usual in the derivations. This makes the book easily accessible to anyone with a background of calculus, statistical thermodynamics and elementary quantum chemistry. (orig./HK)

  12. Probabilistic methods in the field of reactor safety in Germany

    Energy Technology Data Exchange (ETDEWEB)

    Birkhofer, A [Technische Univ. Muenchen (Germany, F.R.). Lehrstuhl fuer Reaktordynamik und Reaktorsicherheit

    1979-01-01

    The present status and future prospects in Germany of reliability, as well as risk analysis, in the field of reactor safety are examined. The development of analytical methods with respect to the available data base is reviewed with consideration of the roles of reliability codes, component data, common mode failures, human influence, structural analysis and process computers. Some examples of the application of probability assessments are discussed and the extension of reliability analysis beyond the loss-of-coolant accident is considered. In the case of risk analysis, the object is to determine not only the probability of failure of systems but also the probability and extent of possible consequences. Some risk studies under investigation in Germany and the methodology of risk analysis are discussed. Reliability and risk analysis are involved to an increasing extent in safety research and licensing procedures and their influence in other fields such as the public perception of risk is also discussed.

  13. Variational method for integrating radial gradient field

    Science.gov (United States)

    Legarda-Saenz, Ricardo; Brito-Loeza, Carlos; Rivera, Mariano; Espinosa-Romero, Arturo

    2014-12-01

    We propose a variational method for integrating information obtained from circular fringe pattern. The proposed method is a suitable choice for objects with radial symmetry. First, we analyze the information contained in the fringe pattern captured by the experimental setup and then move to formulate the problem of recovering the wavefront using techniques from calculus of variations. The performance of the method is demonstrated by numerical experiments with both synthetic and real data.

  14. ASSESSMENT METHODS OF INTERNAL AUDIT

    Directory of Open Access Journals (Sweden)

    Elena RUSE

    2015-12-01

    Full Text Available Internal audit services are more and more needed within economic entities, because on one hand they are directly subordinated to the general manager, on the other hand there is an increase in credit to its recommendations, estimating that internal audit is more than just a simple compliance check based on an established referral system. Our research focuses on evaluating the impact of theory and practice in the application of internal audit process. The added value brought by internal audit function to the economic entity it is pretty difficult to establish and requires effective ways and criteria of measured. In this regard, we will try to present ways to analyze internal audit’s activity by reference to some performance indicators or other specific methods. We used as research techniques: literature review, applied research and constructive research.

  15. Accurate method of the magnetic field measurement of quadrupole magnets

    International Nuclear Information System (INIS)

    Kumada, M.; Sakai, I.; Someya, H.; Sasaki, H.

    1983-01-01

    We present an accurate method of the magnetic field measurement of the quadrupole magnet. The method of obtaining the information of the field gradient and the effective focussing length is given. A new scheme to obtain the information of the skew field components is also proposed. The relative accuracy of the measurement was 1 x 10 -4 or less. (author)

  16. Damped time advance methods for particles and EM fields

    International Nuclear Information System (INIS)

    Friedman, A.; Ambrosiano, J.J.; Boyd, J.K.; Brandon, S.T.; Nielsen, D.E. Jr.; Rambo, P.W.

    1990-01-01

    Recent developments in the application of damped time advance methods to plasma simulations include the synthesis of implicit and explicit ''adjustably damped'' second order accurate methods for particle motion and electromagnetic field propagation. This paper discusses this method

  17. The experimental field work as practical learning method

    Directory of Open Access Journals (Sweden)

    Nicolás Fernández Losa

    2014-11-01

    Full Text Available This paper describes a teaching experience about experimental field work as practical learning method implemented in the subject of Organizational Behaviour. With this teaching experience we pretend to change the practical training, as well as in its evaluation process, in order to favour the development of transversal skills of students. For this purpose, the use of a practice plan, tackled through an experimental field work and carried out with the collaboration of a business organization within a work team (as organic unity of learning, arises as an alternative to the traditional method of practical teachings and allows the approach of business reality into the classroom, as well as actively promote the use of transversal skills. In particular, we develop the experience in three phases. Initially, the students, after forming a working group and define a field work project, should get the collaboration of a nearby business organization in which to obtain data on one or more functional areas of organizational behaviour. Subsequently, students carry out the field work with the realization of the scheduled visits and elaboration of a memory to establish a diagnosis of the strategy followed by the company in these functional areas in order to propose and justify alternative actions that improve existing ones. Finally, teachers assess the different field work memories and their public presentations according to evaluation rubrics, which try to objectify and unify to the maximum the evaluation criteria and serve to guide the learning process of students. The results of implementation of this teaching experience, measured through a Likert questionnaire, are very satisfactory for students.

  18. Enhancing Institutional Assessment Efforts through Qualitative Methods

    Science.gov (United States)

    Van Note Chism, Nancy; Banta, Trudy W.

    2007-01-01

    Qualitative methods can do much to describe context and illuminate the why behind patterns encountered in institutional assessment. Alone, or in combination with quantitative methods, they should be the approach of choice for many of the most important assessment questions. (Contains 1 table.)

  19. A method to assess maritime resilience

    NARCIS (Netherlands)

    Rypkema, J.A.; Beek, F.A. van der; Schraagen, J.M.C.; Winkelman, J.W.; Wijngaarden, M. van

    2015-01-01

    The aim of this study is to develop a multi-level resilience analysis method (RAM) to assess risk and performance variability in current maritime socio-technical systems (STSs). The method integrates Hollnagel’s four resilience abilities to assess a system’s ability to effectively cope with

  20. Development on Vulnerability Assessment Methods of PPS

    Institute of Scientific and Technical Information of China (English)

    MIAO; Qiang; ZHANG; Wen-liang; BU; Li-xin; YIN; Hong-he; LI; Xin-jun; FANG; Xin

    2013-01-01

    Through investigating information from domestic and abroad,joint the domestic assessment experience,we present a set of physical protection system(PPS)vulnerability assessment methods for on-operating nuclear power plants and for on-designing nuclear facilities.The methods will help to strengthen and upgrade the security measures of the nuclear facilities,improve the effectiveness and

  1. Assessment of physical protection systems: EVA method

    International Nuclear Information System (INIS)

    Bernard, J.-L.; Lamotte, C.; Jorda, A.

    2001-01-01

    CEA's missions in various sectors of activity such as nuclear, defence, industrial contracts and the associated regulatory requirements, make it necessary to develop a strategy in the field of physical protection. In particular, firms having nuclear materials are subject to the July 25, 1980 law no.80-572 on the protection and control of nuclear materials. A holding permit delivered by the regulatory authority is conditioned to the protection by the operator of the nuclear materials used. In France it is the nuclear operator who must demonstrate, in the form of a security study, that potential aggressors would be neutralised before they could escape with the material. To meet these requirements, we have developed methods to assess the vulnerability of our facilities. The EVA method, the French acronym for 'Evaluation de la vulnerabilite des Acces' (access vulnerability system) allows dealing with internal and external threats involving brutal actions. In scenarios relating to external threat, the intruders get past the various barriers of our protection system, attempting to steal a large volume of material in one swoop and then escape. In the case of internal threat, the goal is the same. However, as the intruder usually has access to the material in the scope of his activities, the action begins at the level of the target. Our protection system is based on in-depth defense where the intruders are detected and then delayed in their advance towards their target to allow time for intervention forces to intercept them

  2. Study of field assessment methods and worker risks for processing alternatives to support principles for FUSRAP waste materials. Part 1: Treatment methods and comparative risks of thorium removal from waste residues

    Energy Technology Data Exchange (ETDEWEB)

    Porter, R.D.; Hamby, D.M.; Martin, J.E.

    1997-07-01

    This study was done to examine the risks of remediation and the effectiveness of removal methods for thorium and its associated radioactive decay products from various soils and wastes associated with DOE`s Formerly Utilized Sites Remedial Action Program (FUSRAP). Its purpose was to provide information to the Environmental Management Advisory Board`s FUSRAP Committee for use in its deliberation of guiding principles for FUSRAP sites, in particular the degree to which treatment should be considered in the FUSRAP Committee`s recommendations. Treatment of FUSRAP wastes to remove thorium could be beneficial to management of lands that contain thorium if such treatment were effective and cost efficient. It must be recognized, however, that treatment methods invariably require workers to process residues and waste materials usually with bulk handling techniques. These processes expose workers to the radioactivity in the materials, therefore, workers would incur radiological risks in addition to industrial accident risks. An important question is whether the potential reduction of future radiological risks to members of the public justifies the risks that are incurred by remediation workers due to handling materials. This study examines, first, the effectiveness of treatment and then the risks that would be associated with remediation. Both types of information should be useful for decisions on whether and how to apply thorium removal methods to FUSRAP waste materials.

  3. Study of field assessment methods and worker risks for processing alternatives to support principles for FURSRAP waste materials. Part 1: Treatment methods and comparative risks of thorium removal from waste residues

    International Nuclear Information System (INIS)

    Porter, R.D.; Hamby, D.M.; Martin, J.E.

    1997-07-01

    This study was done to examine the risks of remediation and the effectiveness of removal methods for thorium and its associated radioactive decay products from various soils and wastes associated with DOE's Formerly Utilized Sites Remedial Action Program (FUSRAP). Its purpose was to provide information to the Environmental Management Advisory Board's FUSRAP Committee for use in its deliberation of guiding principles for FUSRAP sites, in particular the degree to which treatment should be considered in the FUSRAP Committee's recommendations. Treatment of FUSRAP wastes to remove thorium could be beneficial to management of lands that contain thorium if such treatment were effective and cost efficient. It must be recognized, however, that treatment methods invariably require workers to process residues and waste materials usually with bulk handling techniques. These processes expose workers to the radioactivity in the materials, therefore, workers would incur radiological risks in addition to industrial accident risks. An important question is whether the potential reduction of future radiological risks to members of the public justifies the risks that are incurred by remediation workers due to handling materials. This study examines, first, the effectiveness of treatment and then the risks that would be associated with remediation. Both types of information should be useful for decisions on whether and how to apply thorium removal methods to FUSRAP waste materials

  4. Calibration and uncertainty in electromagnetic fields measuring methods

    International Nuclear Information System (INIS)

    Anglesio, L.; Crotti, G.; Borsero, M.; Vizio, G.

    1999-01-01

    Calibration and reliability in electromagnetic field measuring methods are assured by calibration of measuring instruments. In this work are illustrated systems for generation of electromagnetic fields at low and high frequency, calibration standard and accuracy [it

  5. Mean field methods for cortical network dynamics

    DEFF Research Database (Denmark)

    Hertz, J.; Lerchner, Alexander; Ahmadi, M.

    2004-01-01

    We review the use of mean field theory for describing the dynamics of dense, randomly connected cortical circuits. For a simple network of excitatory and inhibitory leaky integrate- and-fire neurons, we can show how the firing irregularity, as measured by the Fano factor, increases...... with the strength of the synapses in the network and with the value to which the membrane potential is reset after a spike. Generalizing the model to include conductance-based synapses gives insight into the connection between the firing statistics and the high- conductance state observed experimentally in visual...

  6. Accuracy Assessment Field Data for American Samoa

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project is a cooperative effort among the National Ocean Service, National Centers for Coastal Ocean Science, Center for Coastal Monitoring and Assessment; the...

  7. Methods for land use impact assessment: A review

    International Nuclear Information System (INIS)

    Perminova, Tataina; Sirina, Natalia; Laratte, Bertrand; Baranovskaya, Natalia; Rikhvanov, Leonid

    2016-01-01

    Many types of methods to assess land use impact have been developed. Nevertheless a systematic synthesis of all these approaches is necessary to highlight the most commonly used and most effective methods. Given the growing interest in this area of research, a review of the different methods of assessing land use impact (LUI) was performed using bibliometric analysis. One hundred eighty seven articles of agricultural and biological science, and environmental sciences were examined. According to our results, the most frequently used land use assessment methods are Life-Cycle Assessment, Material Flow Analysis/Input–Output Analysis, Environmental Impact Assessment and Ecological Footprint. Comparison of the methods allowed their specific features to be identified and to arrive at the conclusion that a combination of several methods is the best basis for a comprehensive analysis of land use impact assessment. - Highlights: • We identified the most frequently used methods in land use impact assessment. • A comparison of the methods based on several criteria was carried out. • Agricultural land use is by far the most common area of study within the methods. • Incentive driven methods, like LCA, arouse the most interest in this field.

  8. Methods for land use impact assessment: A review

    Energy Technology Data Exchange (ETDEWEB)

    Perminova, Tataina, E-mail: tatiana.perminova@utt.fr [Research Centre for Environmental Studies and Sustainability, University of Technology of Troyes, CNRS UMR 6281, 12 Rue Marie Curie CS 42060, F-10004 Troyes Cedex (France); Department of Geoecology and Geochemistry, Institute of Natural Resources, National Research Tomsk Polytechnic University, 30 Lenin Avenue, 634050 Tomsk (Russian Federation); Sirina, Natalia, E-mail: natalia.sirina@utt.fr [Research Centre for Environmental Studies and Sustainability, University of Technology of Troyes, CNRS UMR 6281, 12 Rue Marie Curie CS 42060, F-10004 Troyes Cedex (France); Laratte, Bertrand, E-mail: bertrand.laratte@utt.fr [Research Centre for Environmental Studies and Sustainability, University of Technology of Troyes, CNRS UMR 6281, 12 Rue Marie Curie CS 42060, F-10004 Troyes Cedex (France); Baranovskaya, Natalia, E-mail: natalya.baranovs@mail.ru [Department of Geoecology and Geochemistry, Institute of Natural Resources, National Research Tomsk Polytechnic University, 30 Lenin Avenue, 634050 Tomsk (Russian Federation); Rikhvanov, Leonid, E-mail: rikhvanov@tpu.ru [Department of Geoecology and Geochemistry, Institute of Natural Resources, National Research Tomsk Polytechnic University, 30 Lenin Avenue, 634050 Tomsk (Russian Federation)

    2016-09-15

    Many types of methods to assess land use impact have been developed. Nevertheless a systematic synthesis of all these approaches is necessary to highlight the most commonly used and most effective methods. Given the growing interest in this area of research, a review of the different methods of assessing land use impact (LUI) was performed using bibliometric analysis. One hundred eighty seven articles of agricultural and biological science, and environmental sciences were examined. According to our results, the most frequently used land use assessment methods are Life-Cycle Assessment, Material Flow Analysis/Input–Output Analysis, Environmental Impact Assessment and Ecological Footprint. Comparison of the methods allowed their specific features to be identified and to arrive at the conclusion that a combination of several methods is the best basis for a comprehensive analysis of land use impact assessment. - Highlights: • We identified the most frequently used methods in land use impact assessment. • A comparison of the methods based on several criteria was carried out. • Agricultural land use is by far the most common area of study within the methods. • Incentive driven methods, like LCA, arouse the most interest in this field.

  9. Efficient Training Methods for Conditional Random Fields

    Science.gov (United States)

    2008-02-01

    Learning (ICML), 2007. [63] Bruce G. Lindsay. Composite likelihood methods. Contemporary Mathematics, pages 221–239, 1988. 189 [64] Yan Liu, Jaime ...Conference on Machine Learning (ICML), pages 737–744, 2005. [107] Erik F. Tjong Kim Sang and Sabine Buchholz. Introduction to the CoNLL-2000 shared task

  10. Assessment methods for the evaluation of vitiligo.

    Science.gov (United States)

    Alghamdi, K M; Kumar, A; Taïeb, A; Ezzedine, K

    2012-12-01

    There is no standardized method for assessing vitiligo. In this article, we review the literature from 1981 to 2011 on different vitiligo assessment methods. We aim to classify the techniques available for vitiligo assessment as subjective, semi-objective or objective; microscopic or macroscopic; and as based on morphometry or colorimetry. Macroscopic morphological measurements include visual assessment, photography in natural or ultraviolet light, photography with computerized image analysis and tristimulus colorimetry or spectrophotometry. Non-invasive micromorphological methods include confocal laser microscopy (CLM). Subjective methods include clinical evaluation by a dermatologist and a vitiligo disease activity score. Semi-objective methods include the Vitiligo Area Scoring Index (VASI) and point-counting methods. Objective methods include software-based image analysis, tristimulus colorimetry, spectrophotometry and CLM. Morphometry is the measurement of the vitiliginous surface area, whereas colorimetry quantitatively analyses skin colour changes caused by erythema or pigment. Most methods involve morphometry, except for the chromameter method, which assesses colorimetry. Some image analysis software programs can assess both morphometry and colorimetry. The details of these programs (Corel Draw, Image Pro Plus, AutoCad and Photoshop) are discussed in the review. Reflectance confocal microscopy provides real-time images and has great potential for the non-invasive assessment of pigmentary lesions. In conclusion, there is no single best method for assessing vitiligo. This review revealed that VASI, the rule of nine and Wood's lamp are likely to be the best techniques available for assessing the degree of pigmentary lesions and measuring the extent and progression of vitiligo in the clinic and in clinical trials. © 2012 The Authors. Journal of the European Academy of Dermatology and Venereology © 2012 European Academy of Dermatology and Venereology.

  11. Thevenin Equivalent Method for Dynamic Contingency Assessment

    DEFF Research Database (Denmark)

    Møller, Jakob Glarbo; Jóhannsson, Hjörtur; Østergaard, Jacob

    2015-01-01

    A method that exploits Thevenin equivalent representation for obtaining post-contingency steady-state nodal voltages is integrated with a method of detecting post-contingency aperiodic small-signal instability. The task of integrating stability assessment with contingency assessment is challenged...... by the cases of unstable post-contingency conditions. For unstable postcontingency conditions there exists no credible steady-state which can be used for basis of a stability assessment. This paper demonstrates how Thevenin Equivalent methods can be applied in algebraic representation of such bifurcation...... points which may be used in assessment of post-contingency aperiodic small-signal stability. The assessment method is introduced with a numeric example....

  12. Assessment of proposed electromagnetic quantum vacuum energy extraction methods

    OpenAIRE

    Moddel, Garret

    2009-01-01

    In research articles and patents several methods have been proposed for the extraction of zero-point energy from the vacuum. None has been reliably demonstrated, but the proposals remain largely unchallenged. In this paper the feasibility of these methods is assessed in terms of underlying thermodynamics principles of equilibrium, detailed balance, and conservation laws. The methods are separated into three classes: nonlinear processing of the zero-point field, mechanical extraction using Cas...

  13. Pairing interaction method in crystal field theory

    International Nuclear Information System (INIS)

    Dushin, R.B.

    1989-01-01

    Expressions, permitting to describe matrix elements of secular equation for metal-ligand pairs via parameters of the method of pairing interactions, genealogical coefficients and Clebsch-Gordan coefficients, are given. The expressions are applicable to any level or term of f n and d n configurations matrix elements for the terms of the maximum multiplicity of f n and d n configurations and also for the main levels of f n configurations are tabulated

  14. Comparison of different dose calculation methods for irregular photon fields

    International Nuclear Information System (INIS)

    Zakaria, G.A.; Schuette, W.

    2000-01-01

    In this work, 4 calculation methods (Wrede method, Clarskon method of sector integration, beam-zone method of Quast and pencil-beam method of Ahnesjoe) are introduced to calculate point doses in different irregular photon fields. The calculations cover a typical mantle field, an inverted Y-field and different blocked fields for 4 and 10 MV photon energies. The results are compared to those of measurements in a water phantom. The Clarkson and the pencil-beam method have been proved to be the methods of equal standard in relation to accuracy. Both of these methods are being distinguished by minimum deviations and applied in our clinical routine work. The Wrede and beam-zone methods deliver useful results to central beam and yet provide larger deviations in calculating points beyond the central axis. (orig.) [de

  15. Stream temperature investigations: field and analytic methods

    Science.gov (United States)

    Bartholow, J.M.

    1989-01-01

    This document provides guidance to the user of the U.S. Fish and Wildlife Service’s Stream Network Temperature Model (SNTEMP). Planning a temperature study is discussed in terms of understanding the management objectives and ensuring that the questions will be accurately answered with the modeling approach being used. A sensitivity analysis of SNTEMP is presented to illustrate which input variables are most important in predicting stream temperatures. This information helps prioritize data collection activities, highlights the need for quality control, focuses on which parameters can be estimated rather than measured, and offers a broader perspective on management options in terms of knowing where the biggest temperature response will be felt. All of the major input variables for stream geometry, meteorology, and hydrology are discussed in detail. Each variable is defined, with guidance given on how to measure it, what kind of equipment to use, where to obtain it from another agency, and how to calculate it if the data are in a form other than that required by SNTEMP. Examples are presented for the various forms in which water temperature, discharge, and meteorological data are commonly found. Ranges of values for certain input variables that are difficult to measure of estimate are given. Particular attention is given to those variables not commonly understood by field biologists likely to be involved in a stream temperature study. Pertinent literature is cited for each variable, with emphasis on how other people have treated particular problems and on results they have found.

  16. EPA Field Manual for Coral Reef Assessments

    Science.gov (United States)

    The Water Quality Research Program (WQRP) supports development of coral reef biological criteria. Research is focused on developing methods and tools to support implementation of legally defensible biological standards for maintaining biological integrity, which is protected by ...

  17. Performance assessment plans and methods for the Salt Repository Project

    International Nuclear Information System (INIS)

    1984-08-01

    This document presents the preliminary plans and anticipated methods of the Salt Repository Project (SRP) for assessing the postclosure and radiological aspects of preclosure performance of a nuclear waste repository in salt. This plan is intended to be revised on an annual basis. The emphasis in this preliminary effort is on the method of conceptually dividing the system into three subsystems (the very near field, the near field, and the far field) and applying models to analyze the behavior of each subsystem and its individual components. The next revision will contain more detailed plans being developed as part of Site Characterization Plan (SCP) activities. After a brief system description, this plan presents the performance targets which have been established for nuclear waste repositories by regulatory agencies (Chapter 3). The SRP approach to modeling, including sensitivity and uncertainty techniques is then presented (Chapter 4). This is followed by a discussion of scenario analysis (Chapter 5), a presentation of preliminary data needs as anticipated by the SRP (Chapter 6), and a presentation of the SRP approach to postclosure assessment of the very near field, the near field, and the far field (Chapters 7, 8, and 9, respectively). Preclosure radiological assessment is discussed in Chapter 10. Chapter 11 presents the SRP approach to code verification and validation. Finally, the Appendix lists all computer codes anticipated for use in performance assessments. The list of codes will be updated as plans are revised

  18. Comparative analysis of selected hydromorphological assessment methods

    Czech Academy of Sciences Publication Activity Database

    Šípek, Václav; Matoušková, M.; Dvořák, M.

    2010-01-01

    Roč. 169, 1-4 (2010), s. 309-319 ISSN 0167-6369 Institutional support: RVO:67985874 Keywords : Hydromorphology * Ecohydromorphological river habitat assessment: EcoRivHab * Rapid Bioassessment Protocol * LAWA Field and Overview Survey * Libechovka River * Bilina River * Czech Republic Subject RIV: DA - Hydrology ; Limnology Impact factor: 1.436, year: 2010

  19. Analyzed method for calculating the distribution of electrostatic field

    International Nuclear Information System (INIS)

    Lai, W.

    1981-01-01

    An analyzed method for calculating the distribution of electrostatic field under any given axial gradient in tandem accelerators is described. This method possesses satisfactory accuracy compared with the results of numerical calculation

  20. Risk assessment theory, methods, and applications

    CERN Document Server

    Rausand, Marvin

    2011-01-01

    With its balanced coverage of theory and applications along with standards and regulations, Risk Assessment: Theory, Methods, and Applications serves as a comprehensive introduction to the topic. The book serves as a practical guide to current risk analysis and risk assessment, emphasizing the possibility of sudden, major accidents across various areas of practice from machinery and manufacturing processes to nuclear power plants and transportation systems. The author applies a uniform framework to the discussion of each method, setting forth clear objectives and descriptions, while also shedding light on applications, essential resources, and advantages and disadvantages. Following an introduction that provides an overview of risk assessment, the book is organized into two sections that outline key theory, methods, and applications. * Introduction to Risk Assessment defines key concepts and details the steps of a thorough risk assessment along with the necessary quantitative risk measures. Chapters outline...

  1. ASSESSMENT OF THE EFFICIENCY OF DISINFECTION METHOD ...

    African Journals Online (AJOL)

    eobe

    ABSTRACT. The efficiencies of three disinfection methods namely boiling, water guard and pur purifier were assessed. ... Water is an indispensable resource for supporting life systems [2- ...... developing country context: improving decisions.

  2. Scientific method, adversarial system, and technology assessment

    Science.gov (United States)

    Mayo, L. H.

    1975-01-01

    A basic framework is provided for the consideration of the purposes and techniques of scientific method and adversarial systems. Similarities and differences in these two techniques of inquiry are considered with reference to their relevance in the performance of assessments.

  3. Assessment of procurement methods used for executing ...

    African Journals Online (AJOL)

    Assessment of procurement methods used for executing maintenance works in Lagos state. ... Ethiopian Journal of Environmental Studies and Management ... Others are risk allocation, price competition and flexibility of contract. Finally, better ...

  4. Personality, Assessment Methods and Academic Performance

    Science.gov (United States)

    Furnham, Adrian; Nuygards, Sarah; Chamorro-Premuzic, Tomas

    2013-01-01

    This study examines the relationship between personality and two different academic performance (AP) assessment methods, namely exams and coursework. It aimed to examine whether the relationship between traits and AP was consistent across self-reported versus documented exam results, two different assessment techniques and across different…

  5. The STIG : A new SDI assessment method

    NARCIS (Netherlands)

    Nushi, B.; Van Loenen, B.; Crompvoets, J.

    2015-01-01

    To stimulate the Spatial Data Infrastructures (SDI) development effectively and efficiently, it is key to assess the progress and benefits of the SDI. Currently, several SDI assessment methods exist. However, these are still in an infant stage and none of these appear to meet the requirements of

  6. Field radiometric methods of prospecting and exploration for uranium ores

    International Nuclear Information System (INIS)

    Gorbushina, L.V.; Savenko, E.I.; Serdyukova, A.S.

    1978-01-01

    The textbook includes two main chapters which describe gamma- and emanation field radiometric methods. The textbook is intended for geology and geophysics students having training practice in field radiometric methods and is additional to the course of lectures. The textbook can be used in the''Radiometry'' course which is studied in appropriate geological and technical colleges

  7. LOMEGA: a low frequency, field implicit method for plasma simulation

    International Nuclear Information System (INIS)

    Barnes, D.C.; Kamimura, T.

    1982-04-01

    Field implicit methods for low frequency plasma simulation by the LOMEGA (Low OMEGA) codes are described. These implicit field methods may be combined with particle pushing algorithms using either Lorentz force or guiding center force models to study two-dimensional, magnetized, electrostatic plasmas. Numerical results for ωsub(e)deltat>>1 are described. (author)

  8. The Background-Field Method and Noninvariant Renormalization

    International Nuclear Information System (INIS)

    Avdeev, L.V.; Kazakov, D.I.; Kalmykov, M.Yu.

    1994-01-01

    We investigate the consistency of the background-field formalism when applying various regularizations and renormalization schemes. By an example of a two-dimensional σ model it is demonstrated that the background-field method gives incorrect results when the regularization (and/or renormalization) is noninvariant. In particular, it is found that the cut-off regularization and the differential renormalization belong to this class and are incompatible with the background-field method in theories with nonlinear symmetries. 17 refs

  9. Methods for regional assessment of geothermal resources

    Science.gov (United States)

    Muffler, P.; Cataldi, R.

    1978-01-01

    A consistent, agreed-upon terminology is prerequisite for geothermal resource assessment. Accordingly, we propose a logical, sequential subdivision of the "geothermal resource base", accepting its definition as all the thermal energy in the earth's crust under a given area, measured from mean annual temperature. That part of the resource base which is shallow enough to be tapped by production drilling is termed the "accessible resource base", and it in turn is divided into "useful" and "residual" components. The useful component (i.e. the thermal energy that could reasonably be extracted at costs competitive with other forms of energy at some specified future time) is termed the "geothermal resource". This in turn is divided into "economic" and "subeconomic" components, based on conditions existing at the time of assessment. In the format of a McKelvey diagram, this logic defines the vertical axis (degree of economic feasibility). The horizontal axis (degree of geologic assurance) contains "identified" and "undiscovered" components. "Reserve" is then designated as the identified economic resource. All categories should be expressed in units of thermal energy, with resource and reserve figures calculated at wellhead, prior to the inevitable large losses inherent in any practical thermal use or in conversion to electricity. Methods for assessing geothermal resources can be grouped into 4 classes: (a) surface thermal flux, (b) volume, (c) planar fracture and (d) magmatic heat budget. The volume method appears to be most useful because (1) it is applicable to virtually any geologic environment, (2) the required parameters can in Sprinciple be measured or estimated, (3) the inevitable errors are in part compensated and (4) the major uncertainties (recoverability and resupply) are amenable to resolution in the foreseeable future. The major weakness in all the methods rests in the estimation of how much of the accessible resource base can be extracted at some time in the

  10. Method of regulating magnetic field of magnetic pole center

    International Nuclear Information System (INIS)

    Watanabe, Masao; Yamada, Teruo; Kato, Norihiko; Toda, Yojiro; Kaneda, Yasumasa.

    1978-01-01

    Purpose: To provide the subject method comprising using a plurality of magnetic metal pieces having different thicknesses, regulating very easily symmetry of the field of the magnetic pole center depending upon the combination of said metal pieces, thereby obtaining a magnetic field of high precision. Method: The regulation of magnetic field at the central part of the magnetic field is not depending only upon processing of the center plug, axial movement of trim coil and ion source but by providing a magnetic metal piece such as an iron ring, primary higher harmonics of the field at the center of the magnetic field can be regulated simply while the position of the ion source slit is on the equipotential surface in the field. (Yoshihara, H.)

  11. Ground assessment methods for nuclear power plant

    International Nuclear Information System (INIS)

    1985-01-01

    It is needless to say that nuclear power plant must be constructed on the most stable and safe ground. Reliable assessment method is required for the purpose. The Ground Integrity Sub-committee of the Committee of Civil Engineering of Nuclear Power Plant started five working groups, the purpose of which is to systematize the assessment procedures including geological survey, ground examination and construction design. The works of working groups are to establishing assessment method of activities of faults, standardizing the rock classification method, standardizing assessment and indication method of ground properties, standardizing test methods and establishing the application standard for design and construction. Flow diagrams for the procedures of geological survey, for the investigation on fault activities and ground properties of area where nuclear reactor and important outdoor equipments are scheduled to construct, were established. And further, flow diagrams for applying investigated results to design and construction of plant, and for determining procedure of liquidification nature of ground etc. were also established. These systematized and standardized methods of investigation are expected to yield reliable data for assessment of construction site of nuclear power plant and lead to the safety of construction and operation in the future. In addition, the execution of these systematized and detailed preliminary investigation for determining the construction site of nuclear power plant will make much contribution for obtaining nation-wide understanding and faith for the project. (Ishimitsu, A.)

  12. Sensitivity-based virtual fields for the non-linear virtual fields method

    Science.gov (United States)

    Marek, Aleksander; Davis, Frances M.; Pierron, Fabrice

    2017-09-01

    The virtual fields method is an approach to inversely identify material parameters using full-field deformation data. In this manuscript, a new set of automatically-defined virtual fields for non-linear constitutive models has been proposed. These new sensitivity-based virtual fields reduce the influence of noise on the parameter identification. The sensitivity-based virtual fields were applied to a numerical example involving small strain plasticity; however, the general formulation derived for these virtual fields is applicable to any non-linear constitutive model. To quantify the improvement offered by these new virtual fields, they were compared with stiffness-based and manually defined virtual fields. The proposed sensitivity-based virtual fields were consistently able to identify plastic model parameters and outperform the stiffness-based and manually defined virtual fields when the data was corrupted by noise.

  13. The Virtual Fields Method Extracting Constitutive Mechanical Parameters from Full-field Deformation Measurements

    CERN Document Server

    Pierron, Fabrice

    2012-01-01

    The Virtual Fields Method: Extracting Constitutive Mechanical Parameters from Full-field Deformation Measurements is the first book on the Virtual Fields Method (VFM), a technique to identify materials mechanical properties from full-field measurements. Firmly rooted with extensive theoretical description of the method, the book presents numerous examples of application to a wide range of materials (composites, metals, welds, biomaterials) and situations (static, vibration, high strain rate). The authors give a detailed training section with examples of progressive difficulty to lead the reader to program the VFM and include a set of commented Matlab programs as well as GUI Matlab-based software for more general situations. The Virtual Fields Method: Extracting Constitutive Mechanical Parameters from Full-field Deformation Measurements is an ideal book for researchers, engineers, and students interested in applying the VFM to new situations motivated by their research.  

  14. Survey and review of near-field performance assessment

    International Nuclear Information System (INIS)

    Apted, M.J.

    1993-01-01

    The aim of this chapter is to describe the performance assessment (PA) context in which near-field models have been developed and applied. An overview is given of a number of PA studies. Although the focus is on near-field models, the overview covers the full context in which the PAs have been performed, including the purpose of the studies and regulatory context. Special emphasis has been given to the scenarios analyzed in the assessments; the scenarios set the framework for model development and application. Another aspect to consider in a study of near-field modeling from the perspective of total PA is the linking between near-field and far-field assessment. (R.P.) 6 tabs

  15. Two numerical methods for mean-field games

    KAUST Repository

    Gomes, Diogo A.

    2016-01-09

    Here, we consider numerical methods for stationary mean-field games (MFG) and investigate two classes of algorithms. The first one is a gradient flow method based on the variational characterization of certain MFG. The second one uses monotonicity properties of MFG. We illustrate our methods with various examples, including one-dimensional periodic MFG, congestion problems, and higher-dimensional models.

  16. Two numerical methods for mean-field games

    KAUST Repository

    Gomes, Diogo A.

    2016-01-01

    Here, we consider numerical methods for stationary mean-field games (MFG) and investigate two classes of algorithms. The first one is a gradient flow method based on the variational characterization of certain MFG. The second one uses monotonicity properties of MFG. We illustrate our methods with various examples, including one-dimensional periodic MFG, congestion problems, and higher-dimensional models.

  17. Overlay control methodology comparison: field-by-field and high-order methods

    Science.gov (United States)

    Huang, Chun-Yen; Chiu, Chui-Fu; Wu, Wen-Bin; Shih, Chiang-Lin; Huang, Chin-Chou Kevin; Huang, Healthy; Choi, DongSub; Pierson, Bill; Robinson, John C.

    2012-03-01

    Overlay control in advanced integrated circuit (IC) manufacturing is becoming one of the leading lithographic challenges in the 3x and 2x nm process nodes. Production overlay control can no longer meet the stringent emerging requirements based on linear composite wafer and field models with sampling of 10 to 20 fields and 4 to 5 sites per field, which was the industry standard for many years. Methods that have emerged include overlay metrology in many or all fields, including the high order field model method called high order control (HOC), and field by field control (FxFc) methods also called correction per exposure. The HOC and FxFc methods were initially introduced as relatively infrequent scanner qualification activities meant to supplement linear production schemes. More recently, however, it is clear that production control is also requiring intense sampling, similar high order and FxFc methods. The added control benefits of high order and FxFc overlay methods need to be balanced with the increased metrology requirements, however, without putting material at risk. Of critical importance is the proper control of edge fields, which requires intensive sampling in order to minimize signatures. In this study we compare various methods of overlay control including the performance levels that can be achieved.

  18. Method of using triaxial magnetic fields for making particle structures

    Science.gov (United States)

    Martin, James E.; Anderson, Robert A.; Williamson, Rodney L.

    2005-01-18

    A method of producing three-dimensional particle structures with enhanced magnetic susceptibility in three dimensions by applying a triaxial energetic field to a magnetic particle suspension and subsequently stabilizing said particle structure. Combinations of direct current and alternating current fields in three dimensions produce particle gel structures, honeycomb structures, and foam-like structures.

  19. Using slides to test for changes in crown defoliation assessment methods. Part I: Visual assessment of slides.

    Science.gov (United States)

    Dobbertin, Matthias; Hug, Christian; Mizoue, Nobuya

    2004-11-01

    In this study we used photographs of tree crowns to test whether the assessment methods for tree defoliation in Switzerland have changed over time. We randomly selected 24 series of slides of Norway spruce with field assessments made between 1986 and 1995. The slides were randomly arranged and assessed by three experts without prior knowledge of the year when the slide was taken or the tree number. Defoliation was assessed using the Swiss reference photo guide. Although the correlations between the field assessments and slide assessments were high (Spearman's rank correlation coefficient ranged between 0.79 and 0.83), we found significant differences between field and slide assessments (4.3 to 9% underprediction by the slide assessors) and between the slide assessments. However, no significant trends in field assessment methods could be detected. When the mean differences between field and slide assessments were subtracted, in some years, field assessors consistently underpredicted (1990, 1992) or overpredicted defoliation (1987, 1991). Defoliation tended to be overpredicted in slides taken against the light, and underpredicted for trees with more than 25% crown overlap. We conclude that slide series can be used to detect changes in assessment methods. However, potential observer bias calls for more objective methods of assessment.

  20. Measuring methods, registration and signal processing for magnetic field research

    International Nuclear Information System (INIS)

    Nagiello, Z.

    1981-01-01

    Some measuring methods and signal processing systems based on analogue and digital technics, which have been applied in magnetic field research using magnetometers with ferromagnetic transducers, are presented. (author)

  1. New Method for Solving Inductive Electric Fields in the Ionosphere

    Science.gov (United States)

    Vanhamäki, H.

    2005-12-01

    We present a new method for calculating inductive electric fields in the ionosphere. It is well established that on large scales the ionospheric electric field is a potential field. This is understandable, since the temporal variations of large scale current systems are generally quite slow, in the timescales of several minutes, so inductive effects should be small. However, studies of Alfven wave reflection have indicated that in some situations inductive phenomena could well play a significant role in the reflection process, and thus modify the nature of ionosphere-magnetosphere coupling. The input to our calculation method are the time series of the potential part of the ionospheric electric field together with the Hall and Pedersen conductances. The output is the time series of the induced rotational part of the ionospheric electric field. The calculation method works in the time-domain and can be used with non-uniform, time-dependent conductances. In addition no particular symmetry requirements are imposed on the input potential electric field. The presented method makes use of special non-local vector basis functions called Cartesian Elementary Current Systems (CECS). This vector basis offers a convenient way of representing curl-free and divergence-free parts of 2-dimensional vector fields and makes it possible to solve the induction problem using simple linear algebra. The new calculation method is validated by comparing it with previously published results for Alfven wave reflection from uniformly conducting ionosphere.

  2. Approaches and methods of risk assessment

    International Nuclear Information System (INIS)

    Rowe, W.D.

    1983-01-01

    The classification system of risk assessment includes the categories: 1) risk comparisons, 2) cost-effectiveness of risk reduction, 3) balancing of costs, risks and benefits against one another, 4. Metasystems. An overview of methods and systems reveals that no single method can be applied to all cases and situations. The visibility of the process and the absolute consideration of all aspects of judging are, however, of first and fore most importance. (DG) [de

  3. Assessment of ELF magnetic fields produced by independent power lines

    International Nuclear Information System (INIS)

    Lucca, G.

    2008-01-01

    In this paper, the problem of assessing the ELF (extremely low-frequency) magnetic fields produced, in a certain area characterised by the presence of more than one independent power line, is faced. The use of the incoherent summation of the single contributions, as an advantageous estimator of the total magnetic field, is proposed and justified by means of a heuristic procedure. This kind of approach can be seen as a useful and practical tool to be employed in environmental impact analysis and in assessing long-term human exposure to ELF magnetic fields. (authors)

  4. Methods for assessing Phytophthora ramorum chlamydospore germination

    Science.gov (United States)

    Joyce Eberhart; Elilzabeth Stamm; Jennifer Parke

    2013-01-01

    Germination of chlamydospores is difficult to accurately assess when chlamydospores are attached to remnants of supporting hyphae. We developed two approaches for closely observing and rigorously quantifying the frequency of chlamydospore germination in vitro. The plate marking and scanning method was useful for quantifying germination of large...

  5. Assessment of field training for nuclear operations personnel

    Energy Technology Data Exchange (ETDEWEB)

    White, M [Safety Management Services, Inc. (Canada)

    1995-08-01

    Training of station personnel is an important component of the safe operation of the nuclear generating station. On-the-job training (OJT) is an important component of training. The AECB initiated this project to develop a process to assess the effectiveness of OJT for field operators, and perform an initial trial of the developed process. This report describes the recommended process to assess the effectiveness of OJT for field operators, as well as the results of the initial assessment at Pickering Nuclear Generating Station. The assessment`s conclusions included: (1) Ontario Hydro policies and procedures are generally consistent with industry guidelines requiring a systematic approach to training; (2) Pickering NGS field operator performance is not always consistent with documented station requirements and standards, nor industry guidelines and practices; and (3) The Pickering NGS field operator on-the-job training is not consistent with a systematic approach to training, a requirement recognized in Ontario Hydro`s Policy NGD 113, and does not contribute to a high level of performance in field operator tasks. Recommendations are made regarding the use of the developed process for future assessments of on-the-job training at nuclear power plants. (author). 36 refs., 4 tabs., 3 figs.

  6. 3D electric field calculation with surface charge method

    International Nuclear Information System (INIS)

    Yamada, S.

    1992-01-01

    This paper describes an outline and some examples of three dimensional electric field calculations with a computer code developed at NIRS. In the code, a surface charge method is adopted because of it's simplicity in the mesh establishing procedure. The charge density in a triangular mesh is assumed to distribute with a linear function of the position. The electric field distribution is calculated for a pair of drift tubes with the focusing fingers on the opposing surfaces. The field distribution in an acceleration gap is analyzed with a Fourier-Bessel series expansion method. The calculated results excellently reproduces the measured data with a magnetic model. (author)

  7. Field Method for Integrating the First Order Differential Equation

    Institute of Scientific and Technical Information of China (English)

    JIA Li-qun; ZHENG Shi-wang; ZHANG Yao-yu

    2007-01-01

    An important modern method in analytical mechanics for finding the integral, which is called the field-method, is used to research the solution of a differential equation of the first order. First, by introducing an intermediate variable, a more complicated differential equation of the first order can be expressed by two simple differential equations of the first order, then the field-method in analytical mechanics is introduced for solving the two differential equations of the first order. The conclusion shows that the field-method in analytical mechanics can be fully used to find the solutions of a differential equation of the first order, thus a new method for finding the solutions of the first order is provided.

  8. Force-free magnetic fields - The magneto-frictional method

    Science.gov (United States)

    Yang, W. H.; Sturrock, P. A.; Antiochos, S. K.

    1986-01-01

    The problem under discussion is that of calculating magnetic field configurations in which the Lorentz force j x B is everywhere zero, subject to specified boundary conditions. We choose to represent the magnetic field in terms of Clebsch variables in the form B = grad alpha x grad beta. These variables are constant on any field line so that each field line is labeled by the corresponding values of alpha and beta. When the field is described in this way, the most appropriate choice of boundary conditions is to specify the values of alpha and beta on the bounding surface. We show that such field configurations may be calculated by a magneto-frictional method. We imagine that the field lines move through a stationary medium, and that each element of magnetic field is subject to a frictional force parallel to and opposing the velocity of the field line. This concept leads to an iteration procedure for modifying the variables alpha and beta, that tends asymptotically towards the force-free state. We apply the method first to a simple problem in two rectangular dimensions, and then to a problem of cylindrical symmetry that was previously discussed by Barnes and Sturrock (1972). In one important respect, our new results differ from the earlier results of Barnes and Sturrock, and we conclude that the earlier article was in error.

  9. Clinical experimental stress studies: methods and assessment.

    Science.gov (United States)

    Bali, Anjana; Jaggi, Amteshwar Singh

    2015-01-01

    Stress is a state of threatened homeostasis during which a variety of adaptive processes are activated to produce physiological and behavioral changes. Stress induction methods are pivotal for understanding these physiological or pathophysiological changes in the body in response to stress. Furthermore, these methods are also important for the development of novel pharmacological agents for stress management. The well-described methods to induce stress in humans include the cold pressor test, Trier Social Stress Test, Montreal Imaging Stress Task, Maastricht Acute Stress Test, CO2 challenge test, Stroop test, Paced Auditory Serial Addition Task, noise stress, and Mannheim Multicomponent Stress Test. Stress assessment in humans is done by measuring biochemical markers such as cortisol, cortisol awakening response, dexamethasone suppression test, salivary α-amylase, plasma/urinary norepinephrine, norepinephrine spillover rate, and interleukins. Physiological and behavioral changes such as galvanic skin response, heart rate variability, pupil size, and muscle and/or skin sympathetic nerve activity (microneurography) and cardiovascular parameters such as heart rate, blood pressure, and self-reported anxiety are also monitored to assess stress response. This present review describes these commonly employed methods to induce stress in humans along with stress assessment methods.

  10. Comparison of electric field exposure measurement methods under power lines

    International Nuclear Information System (INIS)

    Korpinen, L.; Kuisti, H.; Tarao, H.; Paeaekkoenen, R.; Elovaara, J.

    2014-01-01

    The object of the study was to investigate extremely low frequency (ELF) electric field exposure measurement methods under power lines. The authors compared two different methods under power lines: in Method A, the sensor was placed on a tripod; and Method B required the measurer to hold the meter horizontally so that the distance from him/her was at least 1.5 m. The study includes 20 measurements in three places under 400 kV power lines. The authors used two commercial three-axis meters, EFA-3 and EFA-300. In statistical analyses, they did not find significant differences between Methods A and B. However, in the future, it is important to take into account that measurement methods can, in some cases, influence ELF electric field measurement results, and it is important to report the methods used so that it is possible to repeat the measurements. (authors)

  11. New method for assessing risks of email

    Science.gov (United States)

    Raja, Seyyed H.; Afrooz, Farzad

    2013-03-01

    E-mail technology, has become one of the requirements of human lives for correspondence between individuals. Given this, the important point is that the messages, server and client of e-mail and correspondences that exchanged between different people have acceptable security, to make people sure to use of this technology. In the information age, many of financial and non financial transactions are done electronically, data exchange takes place via the internet and theft and manipulation of data can make exorbitant cost in terms of integrity, financial, political, economic and culture. E-mail correspondence in there is same and it is very important. With review took place, a method that will focus on email system for risks assessment is not provided. We are examining ways of assessing for other systems and their strengths and weaknesses, then we use Mr Convery method for assessing email risks which it is for assessing network risks. At the end of paper we have offered special table for email risk assessment.

  12. Assessment of field training for nuclear operations personnel

    International Nuclear Information System (INIS)

    White, M.

    1995-08-01

    Training of station personnel is an important component of the safe operation of the nuclear generating station. On-the-job training (OJT) is an important component of training. The AECB initiated this project to develop a process to assess the effectiveness of OJT for field operators, and perform an initial trial of the developed process. This report describes the recommended process to assess the effectiveness of OJT for field operators, as well as the results of the initial assessment at Pickering Nuclear Generating Station. The assessment's conclusions included: (1) Ontario Hydro policies and procedures are generally consistent with industry guidelines requiring a systematic approach to training; (2) Pickering NGS field operator performance is not always consistent with documented station requirements and standards, nor industry guidelines and practices; and (3) The Pickering NGS field operator on-the-job training is not consistent with a systematic approach to training, a requirement recognized in Ontario Hydro's Policy NGD 113, and does not contribute to a high level of performance in field operator tasks. Recommendations are made regarding the use of the developed process for future assessments of on-the-job training at nuclear power plants. (author). 36 refs., 4 tabs., 3 figs

  13. Wave field restoration using three-dimensional Fourier filtering method.

    Science.gov (United States)

    Kawasaki, T; Takai, Y; Ikuta, T; Shimizu, R

    2001-11-01

    A wave field restoration method in transmission electron microscopy (TEM) was mathematically derived based on a three-dimensional (3D) image formation theory. Wave field restoration using this method together with spherical aberration correction was experimentally confirmed in through-focus images of amorphous tungsten thin film, and the resolution of the reconstructed phase image was successfully improved from the Scherzer resolution limit to the information limit. In an application of this method to a crystalline sample, the surface structure of Au(110) was observed in a profile-imaging mode. The processed phase image showed quantitatively the atomic relaxation of the topmost layer.

  14. Statistical methods for assessment of blend homogeneity

    DEFF Research Database (Denmark)

    Madsen, Camilla

    2002-01-01

    In this thesis the use of various statistical methods to address some of the problems related to assessment of the homogeneity of powder blends in tablet production is discussed. It is not straight forward to assess the homogeneity of a powder blend. The reason is partly that in bulk materials......, it is shown how to set up parametric acceptance criteria for the batch that gives a high confidence that future samples with a probability larger than a specified value will pass the USP threeclass criteria. Properties and robustness of proposed changes to the USP test for content uniformity are investigated...

  15. Geophysics Methods in Electrometric Assessment of Dams

    Energy Technology Data Exchange (ETDEWEB)

    Davydov, V. A., E-mail: davydov-va@yandex.ru; Baidikov, S. V., E-mail: badikek@mail.ru; Gorshkov, V. Yu., E-mail: vitalaa@yandex.ru; Malikov, A. V., E-mail: alex.mal.1986@mail.ru [Russian Academy of Sciences, Geophysical Institute, Ural Branch (Russian Federation)

    2016-07-15

    The safety assessment of hydraulic structures is proposed to be conducted via geoelectric measurements, which are capable of assessing the health of earth dams in their natural bedding without intervention in their structure. Geoelectric measurements are shown as being capable of pinpointing hazardous parts of a dam, including areas of elevated seepage. Applications of such methods are shown for a number of mini-dams in the Sverdlovsk region. Aparameter (effective longitudinal conductivity) that may be used to monitor the safety of hydraulic structures is proposed. Quantitative estimates of this parameter are given in terms of the degree of safely.

  16. Extensions of the auxiliary field method to solve Schroedinger equations

    International Nuclear Information System (INIS)

    Silvestre-Brac, Bernard; Semay, Claude; Buisseret, Fabien

    2008-01-01

    It has recently been shown that the auxiliary field method is an interesting tool to compute approximate analytical solutions of the Schroedinger equation. This technique can generate the spectrum associated with an arbitrary potential V(r) starting from the analytically known spectrum of a particular potential P(r). In the present work, general important properties of the auxiliary field method are proved, such as scaling laws and independence of the results on the choice of P(r). The method is extended in order to find accurate analytical energy formulae for radial potentials of the form aP(r) + V(r), and several explicit examples are studied. Connections existing between the perturbation theory and the auxiliary field method are also discussed

  17. Extensions of the auxiliary field method to solve Schroedinger equations

    Energy Technology Data Exchange (ETDEWEB)

    Silvestre-Brac, Bernard [LPSC Universite Joseph Fourier, Grenoble 1, CNRS/IN2P3, Institut Polytechnique de Grenoble, Avenue des Martyrs 53, F-38026 Grenoble-Cedex (France); Semay, Claude; Buisseret, Fabien [Groupe de Physique Nucleaire Theorique, Universite de Mons-Hainaut, Academie universitaire Wallonie-Bruxelles, Place du Parc 20, B-7000 Mons (Belgium)], E-mail: silvestre@lpsc.in2p3.fr, E-mail: claude.semay@umh.ac.be, E-mail: fabien.buisseret@umh.ac.be

    2008-10-24

    It has recently been shown that the auxiliary field method is an interesting tool to compute approximate analytical solutions of the Schroedinger equation. This technique can generate the spectrum associated with an arbitrary potential V(r) starting from the analytically known spectrum of a particular potential P(r). In the present work, general important properties of the auxiliary field method are proved, such as scaling laws and independence of the results on the choice of P(r). The method is extended in order to find accurate analytical energy formulae for radial potentials of the form aP(r) + V(r), and several explicit examples are studied. Connections existing between the perturbation theory and the auxiliary field method are also discussed.

  18. Sheet metals characterization using the virtual fields method

    Science.gov (United States)

    Marek, Aleksander; Davis, Frances M.; Pierron, Fabrice

    2018-05-01

    In this work, a characterisation method involving a deep-notched specimen subjected to a tensile loading is introduced. This specimen leads to heterogeneous states of stress and strain, the latter being measured using a stereo DIC system (MatchID). This heterogeneity enables the identification of multiple material parameters in a single test. In order to identify material parameters from the DIC data, an inverse method called the Virtual Fields Method is employed. The method combined with recently developed sensitivity-based virtual fields allows to optimally locate areas in the test where information about each material parameter is encoded, improving accuracy of the identification over the traditional user-defined virtual fields. It is shown that a single test performed at 45° to the rolling direction is sufficient to obtain all anisotropic plastic parameters, thus reducing experimental effort involved in characterisation. The paper presents the methodology and some numerical validation.

  19. Assessment of Industrial Exposure to Magnetic Fields (invited paper)

    International Nuclear Information System (INIS)

    Chadwick, P.

    1999-01-01

    Magnetic field strengths produced by industrial processes can be very large, but they often exhibit a marked spatial variation. Whilst there may be the potential for exposures of workers to be high, actual exposure will be determined to a great extent by working practices. Possible metrics for epidemiological studies might be based on the temporal variability of exposure as well as maximum operator exposure or time-weighted average exposure and, whilst it might be possible to estimate these quantities from spot magnetic field strength measurements and observed working practices, this might be very difficult to achieve in practice. An alternative would be the use of a logging dosemeter: this paper describes some of the results of exposure assessments carried out in industrial environments with a modified EMDEX II magnetic field dosemeter. Magnetic fields in industrial environments often have waveforms which are not purely sinusoidal. Distortion can be introduced by the magnetic saturation of transformer and motor cores, by rectification, by poor matching between oscillator circuits and loads and when thyristors are used to control power. The resulting repetitive but non-sinusoidal magnetic field waveforms can be recorded and analysed; the spectral data may be incorporated into possible exposure metrics. It is also important to ensure that measurement instrumentation is responding appropriately in a non-sinusoidal field and this can only be done if the spectral content of the field is characterised fully. Some non-sinusoidal magnetic field waveforms cannot be expressed as a harmonic series. Specialist instrumentation and techniques are needed to assess exposure to such fields. Examples of approaches to the assessment of exposure to repetitive and non-repetitive magnetic fields are also discussed. (author)

  20. Assessment of occupational exposure to radio frequency electromagnetic fields

    Directory of Open Access Journals (Sweden)

    Halina Aniołczyk

    2015-06-01

    Full Text Available Background: European Union Directive 2013/35/UE provides for the implementation of EU regulations into national legislation. Our aim is to assess actual health hazards from radiofrequency electromagnetic field (RF EMF (range: 100 kHz – 300 GHz and indicate workplaces with the highest risk to employee health. Material and Methods: Data from measurements of RF EMF performed by the Laboratory of Electromagnetic Hazards in Nofer Institute of Occupational Medicine (Łódź, Poland were analyzed. The analysis covered the results of electric field intensity (E for over 450 selected items. The ranges of protection zones and the extent to which maximum admissible intensity (MAI values were also analyzed. The determinations and measurements of EMF in the work environment met the requirements of Polish Standard, while Polish regulations on the MAI values were used as the criterion for the assessment of the exposure. Results: The highest values of E field intensity at workplaces were measured for: electrosurgery, to 400 V/m, and short-wave diathermy units, to 220 V/m, dielectric welders to 240 V/m, within the FM radio antenna systems, to 180 V/m. The widest protection zones were noted for prototype research instruments, short-wave diathermy units, and dielectric welders. The most excessive (up to 12-fold MAI values were recorded for dielectric welders, short-wave diathermy units (up to 11-fold and microwave diathermy units (up to 8-fold. Conclusions: Our results have confirmed the high RF EMF values for physiotherapists, operators of dielectric welders, and mast maintenance workers in radio communication facilities (especially radio and TV broadcasting stations. Med Pr 2015;66(2:199–212

  1. Assessment of occupational exposure to radiofrequency fields and radiation

    International Nuclear Information System (INIS)

    Cooper, T. G.; Allen, S. G.; Blackwell, R. P.; Litchfield, I.; Mann, S. M.; Pope, J. M.; Van Tongeren, M. J. A.

    2004-01-01

    The use of personal monitors for the assessment of exposure to radiofrequency fields and radiation in potential future epidemiological studies of occupationally exposed populations has been investigated. Data loggers have been developed for use with a commercially available personal monitor and these allowed personal exposure records consisting of time-tagged measurements of electric and magnetic field strength to be accrued over extended periods of the working day. The instrumentation was worn by workers carrying out tasks representative of some of their typical daily activities at a variety of radio sites. The results indicated significant differences in the exposures of workers in various RF environments. A number of measures of exposure have been examined with a view to assessing possible exposure metrics for epidemiological studies. There was generally a good correlation between a given measure of electric field strength and the same measure of magnetic field strength. (authors)

  2. Enhancing Field Research Methods with Mobile Survey Technology

    Science.gov (United States)

    Glass, Michael R.

    2015-01-01

    This paper assesses the experience of undergraduate students using mobile devices and a commercial application, iSurvey, to conduct a neighborhood survey. Mobile devices offer benefits for enhancing student learning and engagement. This field exercise created the opportunity for classroom discussions on the practicalities of urban research, the…

  3. Methods of Environmental Impact Assessment in Colombia

    Directory of Open Access Journals (Sweden)

    Javier Toro Calderón

    2013-10-01

    Full Text Available The Environmental Impact Assessment (EIA in Colombia constitutes the primary tool for making decisions with respect to projects, works and activities (PWA with potential for significant environmental impacts. In the case of the infrastructure of the PWA, the EIA is mandatory and determines the environmental license (EL for construction and operation. This paper analyzes the methods used to assess the environmental impact of the PWA that have applied for licenses with the Ministry of Environment and Sustainable Development. It was found that the method most frequently used is the qualitative proposal by Conesa, with modifications that reduce the effectiveness of the EIA and favor the subjectivity and bias of the evaluator. Finally a series of recom­mendations to improve the process in the country are proposed.

  4. Statistical methods in personality assessment research.

    Science.gov (United States)

    Schinka, J A; LaLone, L; Broeckel, J A

    1997-06-01

    Emerging models of personality structure and advances in the measurement of personality and psychopathology suggest that research in personality and personality assessment has entered a stage of advanced development, in this article we examine whether researchers in these areas have taken advantage of new and evolving statistical procedures. We conducted a review of articles published in the Journal of Personality, Assessment during the past 5 years. Of the 449 articles that included some form of data analysis, 12.7% used only descriptive statistics, most employed only univariate statistics, and fewer than 10% used multivariate methods of data analysis. We discuss the cost of using limited statistical methods, the possible reasons for the apparent reluctance to employ advanced statistical procedures, and potential solutions to this technical shortcoming.

  5. A regularization method for extrapolation of solar potential magnetic fields

    Science.gov (United States)

    Gary, G. A.; Musielak, Z. E.

    1992-01-01

    The mathematical basis of a Tikhonov regularization method for extrapolating the chromospheric-coronal magnetic field using photospheric vector magnetograms is discussed. The basic techniques show that the Cauchy initial value problem can be formulated for potential magnetic fields. The potential field analysis considers a set of linear, elliptic partial differential equations. It is found that, by introducing an appropriate smoothing of the initial data of the Cauchy potential problem, an approximate Fourier integral solution is found, and an upper bound to the error in the solution is derived. This specific regularization technique, which is a function of magnetograph measurement sensitivities, provides a method to extrapolate the potential magnetic field above an active region into the chromosphere and low corona.

  6. Interferometric methods for mapping static electric and magnetic fields

    DEFF Research Database (Denmark)

    Pozzi, Giulio; Beleggia, Marco; Kasama, Takeshi

    2014-01-01

    The mapping of static electric and magnetic fields using electron probes with a resolution and sensitivity that are sufficient to reveal nanoscale features in materials requires the use of phase-sensitive methods such as the shadow technique, coherent Foucault imaging and the Transport of Intensi......) the model-independent determination of the locations and magnitudes of field sources (electric charges and magnetic dipoles) directly from electron holographic data.......The mapping of static electric and magnetic fields using electron probes with a resolution and sensitivity that are sufficient to reveal nanoscale features in materials requires the use of phase-sensitive methods such as the shadow technique, coherent Foucault imaging and the Transport of Intensity...... on theoretical models that form the basis of the quantitative interpretation of electron holographic data. We review the application of electron holography to a variety of samples (including electric fields associated with p–n junctions in semiconductors, quantized magnetic flux in superconductors...

  7. Method of assessing heterogeneity in images

    Science.gov (United States)

    Jacob, Richard E.; Carson, James P.

    2016-08-23

    A method of assessing heterogeneity in images is disclosed. 3D images of an object are acquired. The acquired images may be filtered and masked. Iterative decomposition is performed on the masked images to obtain image subdivisions that are relatively homogeneous. Comparative analysis, such as variogram analysis or correlogram analysis, is performed of the decomposed images to determine spatial relationships between regions of the images that are relatively homogeneous.

  8. Lattice field theories: non-perturbative methods of analysis

    International Nuclear Information System (INIS)

    Weinstein, M.

    1978-01-01

    A lecture is given on the possible extraction of interesting physical information from quantum field theories by studying their semiclassical versions. From the beginning the problem of solving for the spectrum states of any given continuum quantum field theory is considered as a giant Schroedinger problem, and then some nonperturbative methods for diagonalizing the Hamiltonian of the theory are explained without recourse to semiclassical approximations. The notion of a lattice appears as an artifice to handle the problems associated with the familiar infrared and ultraviolet divergences of continuum quantum field theory and in fact for all but gauge theories. 18 references

  9. Multigrid methods for the computation of propagators in gauge fields

    International Nuclear Information System (INIS)

    Kalkreuter, T.

    1992-11-01

    In the present work generalizations of multigrid methods for propagators in gauge fields are investigated. We discuss proper averaging operations for bosons and for staggered fermions. An efficient algorithm for computing C numerically is presented. The averaging kernels C can be used not only in deterministic multigrid computations, but also in multigrid Monte Carlo simulations, and for the definition of block spins and blocked gauge fields in Monte Carlo renormalization group studies of gauge theories. Actual numerical computations of kernels and propagators are performed in compact four-dimensional SU(2) gauge fields. (orig./HSI)

  10. Perspective: Ab initio force field methods derived from quantum mechanics

    Science.gov (United States)

    Xu, Peng; Guidez, Emilie B.; Bertoni, Colleen; Gordon, Mark S.

    2018-03-01

    It is often desirable to accurately and efficiently model the behavior of large molecular systems in the condensed phase (thousands to tens of thousands of atoms) over long time scales (from nanoseconds to milliseconds). In these cases, ab initio methods are difficult due to the increasing computational cost with the number of electrons. A more computationally attractive alternative is to perform the simulations at the atomic level using a parameterized function to model the electronic energy. Many empirical force fields have been developed for this purpose. However, the functions that are used to model interatomic and intermolecular interactions contain many fitted parameters obtained from selected model systems, and such classical force fields cannot properly simulate important electronic effects. Furthermore, while such force fields are computationally affordable, they are not reliable when applied to systems that differ significantly from those used in their parameterization. They also cannot provide the information necessary to analyze the interactions that occur in the system, making the systematic improvement of the functional forms that are used difficult. Ab initio force field methods aim to combine the merits of both types of methods. The ideal ab initio force fields are built on first principles and require no fitted parameters. Ab initio force field methods surveyed in this perspective are based on fragmentation approaches and intermolecular perturbation theory. This perspective summarizes their theoretical foundation, key components in their formulation, and discusses key aspects of these methods such as accuracy and formal computational cost. The ab initio force fields considered here were developed for different targets, and this perspective also aims to provide a balanced presentation of their strengths and shortcomings. Finally, this perspective suggests some future directions for this actively developing area.

  11. Survey and review of near-field performance assessment

    International Nuclear Information System (INIS)

    Apted, M.J.

    1993-01-01

    Chemical reactions control the performance, stability, and rate of degradation of natural and engineered barriers to waste repositories of the near field. Chemical processes are overviewed in this context. Temperature, and associated temperature gradients, are also important parameters in near-field performance assessment. The mechanical conditions of the near-field rock will be perturbed by construction of the underground repository. Mechanical analysis in the near field is further complicated by the introduction of HLW canisters and associated engineered barrier materials. Hydrological processes important to near-field performance include those associated with fluid transport. Considerable discussions and studies have been conducted on the issue of coupling among chemical-thermal-mechanical-hydrological processes; they are overviewed. (R.P.) 2 figs., 2 tabs

  12. A classification scheme for risk assessment methods.

    Energy Technology Data Exchange (ETDEWEB)

    Stamp, Jason Edwin; Campbell, Philip LaRoche

    2004-08-01

    This report presents a classification scheme for risk assessment methods. This scheme, like all classification schemes, provides meaning by imposing a structure that identifies relationships. Our scheme is based on two orthogonal aspects--level of detail, and approach. The resulting structure is shown in Table 1 and is explained in the body of the report. Each cell in the Table represent a different arrangement of strengths and weaknesses. Those arrangements shift gradually as one moves through the table, each cell optimal for a particular situation. The intention of this report is to enable informed use of the methods so that a method chosen is optimal for a situation given. This report imposes structure on the set of risk assessment methods in order to reveal their relationships and thus optimize their usage.We present a two-dimensional structure in the form of a matrix, using three abstraction levels for the rows and three approaches for the columns. For each of the nine cells in the matrix we identify the method type by name and example. The matrix helps the user understand: (1) what to expect from a given method, (2) how it relates to other methods, and (3) how best to use it. Each cell in the matrix represent a different arrangement of strengths and weaknesses. Those arrangements shift gradually as one moves through the table, each cell optimal for a particular situation. The intention of this report is to enable informed use of the methods so that a method chosen is optimal for a situation given. The matrix, with type names in the cells, is introduced in Table 2 on page 13 below. Unless otherwise stated we use the word 'method' in this report to refer to a 'risk assessment method', though often times we use the full phrase. The use of the terms 'risk assessment' and 'risk management' are close enough that we do not attempt to distinguish them in this report. The remainder of this report is organized as follows. In

  13. Human performance assessment: methods and measures

    International Nuclear Information System (INIS)

    Andresen, Gisle; Droeivoldsmo, Asgeir

    2000-10-01

    The Human Error Analysis Project (HEAP) was initiated in 1994. The aim of the project was to acquire insights on how and why cognitive errors occur when operators are engaged in problem solving in advanced integrated control rooms. Since human error had not been studied in the HAlden Man-Machine LABoratory (HAMMLAB) before, it was also necessary to carry out research in methodology. In retrospect, it is clear that much of the methodological work is relevant to human-machine research in general, and not only to research on human error. The purpose of this report is, therefore, to give practitioners and researchers an overview of the methodological parts of HEAP. The scope of the report is limited to methods used throughout the data acquisition process, i.e., data-collection methods, data-refinement methods, and measurement methods. The data-collection methods include various types of verbal protocols, simulator logs, questionnaires, and interviews. Data-refinement methods involve different applications of the Eyecon system, a flexible data-refinement tool, and small computer programs used for rearranging, reformatting, and aggregating raw-data. Measurement methods involve assessment of diagnostic behaviour, erroneous actions, complexity, task/system performance, situation awareness, and workload. The report concludes that the data-collection methods are generally both reliable and efficient. The data-refinement methods, however, should be easier to use in order to facilitate explorative analyses. Although the series of experiments provided an opportunity for measurement validation, there are still uncertainties connected to several measures, due to their reliability still being unknown. (Author). 58 refs.,7 tabs

  14. A proposed impact assessment method for genetically modified plants (AS-GMP Method)

    International Nuclear Information System (INIS)

    Jesus-Hitzschky, Katia Regina Evaristo de; Silveira, Jose Maria F.J. da

    2009-01-01

    An essential step in the development of products based on biotechnology is an assessment of their potential economic impacts and safety, including an evaluation of the potential impact of transgenic crops and practices related to their cultivation on the environment and human or animal health. The purpose of this paper is to provide an assessment method to evaluate the impact of biotechnologies that uses quantifiable parameters and allows a comparative analysis between conventional technology and technologies using GMOs. This paper introduces a method to perform an impact analysis associated with the commercial release and use of genetically modified plants, the Assessment System GMP Method. The assessment is performed through indicators that are arranged according to their dimension criterion likewise: environmental, economic, social, capability and institutional approach. To perform an accurate evaluation of the GMP specific indicators related to genetic modification are grouped in common fields: genetic insert features, GM plant features, gene flow, food/feed field, introduction of the GMP, unexpected occurrences and specific indicators. The novelty is the possibility to include specific parameters to the biotechnology under assessment. In this case by case analysis the factors of moderation and the indexes are parameterized to perform an available assessment.

  15. Improvement of vector compensation method for vehicle magnetic distortion field

    Energy Technology Data Exchange (ETDEWEB)

    Pang, Hongfeng, E-mail: panghongfeng@126.com; Zhang, Qi; Li, Ji; Luo, Shitu; Chen, Dixiang; Pan, Mengchun; Luo, Feilu

    2014-03-15

    Magnetic distortions such as eddy-current field and low frequency magnetic field have not been considered in vector compensation methods. A new compensation method is proposed to suppress these magnetic distortions and improve compensation performance, in which the magnetic distortions related to measurement vectors and time are considered. The experimental system mainly consists of a three-axis fluxgate magnetometer (DM-050), an underwater vehicle and a proton magnetometer, in which the scalar value of magnetic field is obtained with the proton magnetometer and considered to be the true value. Comparing with traditional compensation methods, experimental results show that the magnetic distortions can be further reduced by two times. After compensation, error intensity and RMS error are reduced from 11684.013 nT and 7794.604 nT to 16.219 nT and 5.907 nT respectively. It suggests an effective way to improve the compensation performance of magnetic distortions. - Highlights: • A new vector compensation method is proposed for vehicle magnetic distortion. • The proposed model not only includes magnetometer error but also considers magnetic distortion. • Compensation parameters are computed directly by solving nonlinear equations. • Compared with traditional methods, the proposed method is not related with rotation angle rate. • Error intensity and RMS error can be reduced to 1/2 of the error with traditional methods.

  16. Improvement of vector compensation method for vehicle magnetic distortion field

    International Nuclear Information System (INIS)

    Pang, Hongfeng; Zhang, Qi; Li, Ji; Luo, Shitu; Chen, Dixiang; Pan, Mengchun; Luo, Feilu

    2014-01-01

    Magnetic distortions such as eddy-current field and low frequency magnetic field have not been considered in vector compensation methods. A new compensation method is proposed to suppress these magnetic distortions and improve compensation performance, in which the magnetic distortions related to measurement vectors and time are considered. The experimental system mainly consists of a three-axis fluxgate magnetometer (DM-050), an underwater vehicle and a proton magnetometer, in which the scalar value of magnetic field is obtained with the proton magnetometer and considered to be the true value. Comparing with traditional compensation methods, experimental results show that the magnetic distortions can be further reduced by two times. After compensation, error intensity and RMS error are reduced from 11684.013 nT and 7794.604 nT to 16.219 nT and 5.907 nT respectively. It suggests an effective way to improve the compensation performance of magnetic distortions. - Highlights: • A new vector compensation method is proposed for vehicle magnetic distortion. • The proposed model not only includes magnetometer error but also considers magnetic distortion. • Compensation parameters are computed directly by solving nonlinear equations. • Compared with traditional methods, the proposed method is not related with rotation angle rate. • Error intensity and RMS error can be reduced to 1/2 of the error with traditional methods

  17. Multigrid Methods for the Computation of Propagators in Gauge Fields

    Science.gov (United States)

    Kalkreuter, Thomas

    Multigrid methods were invented for the solution of discretized partial differential equations in order to overcome the slowness of traditional algorithms by updates on various length scales. In the present work generalizations of multigrid methods for propagators in gauge fields are investigated. Gauge fields are incorporated in algorithms in a covariant way. The kernel C of the restriction operator which averages from one grid to the next coarser grid is defined by projection on the ground-state of a local Hamiltonian. The idea behind this definition is that the appropriate notion of smoothness depends on the dynamics. The ground-state projection choice of C can be used in arbitrary dimension and for arbitrary gauge group. We discuss proper averaging operations for bosons and for staggered fermions. The kernels C can also be used in multigrid Monte Carlo simulations, and for the definition of block spins and blocked gauge fields in Monte Carlo renormalization group studies. Actual numerical computations are performed in four-dimensional SU(2) gauge fields. We prove that our proposals for block spins are “good”, using renormalization group arguments. A central result is that the multigrid method works in arbitrarily disordered gauge fields, in principle. It is proved that computations of propagators in gauge fields without critical slowing down are possible when one uses an ideal interpolation kernel. Unfortunately, the idealized algorithm is not practical, but it was important to answer questions of principle. Practical methods are able to outperform the conjugate gradient algorithm in case of bosons. The case of staggered fermions is harder. Multigrid methods give considerable speed-ups compared to conventional relaxation algorithms, but on lattices up to 184 conjugate gradient is superior.

  18. Rapid assessment methods in eye care: An overview

    Directory of Open Access Journals (Sweden)

    Srinivas Marmamula

    2012-01-01

    Full Text Available Reliable information is required for the planning and management of eye care services. While classical research methods provide reliable estimates, they are prohibitively expensive and resource intensive. Rapid assessment (RA methods are indispensable tools in situations where data are needed quickly and where time- or cost-related factors prohibit the use of classical epidemiological surveys. These methods have been developed and field tested, and can be applied across almost the entire gamut of health care. The 1990s witnessed the emergence of RA methods in eye care for cataract, onchocerciasis, and trachoma and, more recently, the main causes of avoidable blindness and visual impairment. The important features of RA methods include the use of local resources, simplified sampling methodology, and a simple examination protocol/data collection method that can be performed by locally available personnel. The analysis is quick and easy to interpret. The entire process is inexpensive, so the survey may be repeated once every 5-10 years to assess the changing trends in disease burden. RA survey methods are typically linked with an intervention. This article provides an overview of the RA methods commonly used in eye care, and emphasizes the selection of appropriate methods based on the local need and context.

  19. WHO's health risk assessment of extremely low frequency electric fields

    International Nuclear Information System (INIS)

    Repacholi, M.H.

    2003-01-01

    The World Health Organization (WHO), the International Commission on Non-Ionizing Radiation Protection (ICNIRP), WHOs scientific collaborating centres (including the UKs National Radiological Protection Board (NRPB) and over 50 participating Member States are participants of WHOs International EMF Project. As part of WHOs health risk assessment process for extremely low frequency fields (ELFs), this workshop was convened by NRPB to assist WHO in evaluating potential health impacts of electrical currents and fields induced by ELF in molecules, cells, tissues and organs of the body. This paper describes the process by which WHO will conduct its health risk assessment. WHO is also trying to provide information on why exposure to ELF magnetic fields seems to be associated with an increased incidence of childhood leukaemia. Are there mechanisms that could lead to this health outcome or does the epidemiological evidence incorporate biases or other factors that need to be further explored? (author)

  20. New numerical methods for quantum field theories on the continuum

    Energy Technology Data Exchange (ETDEWEB)

    Emirdag, P.; Easter, R.; Guralnik, G.S.; Hahn, S.C

    2000-03-01

    The Source Galerkin Method is a new numerical technique that is being developed to solve Quantum Field Theories on the continuum. It is not based on Monte Carlo techniques and has a measure to evaluate relative errors. It promises to increase the accuracy and speed of calculations, and takes full advantage of symmetries of the theory. The application of this method to the non-linear {sigma} model is outlined.

  1. A novel background field removal method for MRI using projection onto dipole fields (PDF).

    Science.gov (United States)

    Liu, Tian; Khalidov, Ildar; de Rochefort, Ludovic; Spincemaille, Pascal; Liu, Jing; Tsiouris, A John; Wang, Yi

    2011-11-01

    For optimal image quality in susceptibility-weighted imaging and accurate quantification of susceptibility, it is necessary to isolate the local field generated by local magnetic sources (such as iron) from the background field that arises from imperfect shimming and variations in magnetic susceptibility of surrounding tissues (including air). Previous background removal techniques have limited effectiveness depending on the accuracy of model assumptions or information input. In this article, we report an observation that the magnetic field for a dipole outside a given region of interest (ROI) is approximately orthogonal to the magnetic field of a dipole inside the ROI. Accordingly, we propose a nonparametric background field removal technique based on projection onto dipole fields (PDF). In this PDF technique, the background field inside an ROI is decomposed into a field originating from dipoles outside the ROI using the projection theorem in Hilbert space. This novel PDF background removal technique was validated on a numerical simulation and a phantom experiment and was applied in human brain imaging, demonstrating substantial improvement in background field removal compared with the commonly used high-pass filtering method. Copyright © 2011 John Wiley & Sons, Ltd.

  2. Field Science Ethnography: Methods For Systematic Observation on an Expedition

    Science.gov (United States)

    Clancey, William J.; Clancy, Daniel (Technical Monitor)

    2001-01-01

    The Haughton-Mars expedition is a multidisciplinary project, exploring an impact crater in an extreme environment to determine how people might live and work on Mars. The expedition seeks to understand and field test Mars facilities, crew roles, operations, and computer tools. I combine an ethnographic approach to establish a baseline understanding of how scientists prefer to live and work when relatively unemcumbered, with a participatory design approach of experimenting with procedures and tools in the context of use. This paper focuses on field methods for systematically recording and analyzing the expedition's activities. Systematic photography and time-lapse video are combined with concept mapping to organize and present information. This hybrid approach is generally applicable to the study of modern field expeditions having a dozen or more multidisciplinary participants, spread over a large terrain during multiple field seasons.

  3. Mathematical methods of many-body quantum field theory

    CERN Document Server

    Lehmann, Detlef

    2004-01-01

    Mathematical Methods of Many-Body Quantum Field Theory offers a comprehensive, mathematically rigorous treatment of many-body physics. It develops the mathematical tools for describing quantum many-body systems and applies them to the many-electron system. These tools include the formalism of second quantization, field theoretical perturbation theory, functional integral methods, bosonic and fermionic, and estimation and summation techniques for Feynman diagrams. Among the physical effects discussed in this context are BCS superconductivity, s-wave and higher l-wave, and the fractional quantum Hall effect. While the presentation is mathematically rigorous, the author does not focus solely on precise definitions and proofs, but also shows how to actually perform the computations.Presenting many recent advances and clarifying difficult concepts, this book provides the background, results, and detail needed to further explore the issue of when the standard approximation schemes in this field actually work and wh...

  4. Evaluation of different field methods for measuring soil water infiltration

    Science.gov (United States)

    Pla-Sentís, Ildefonso; Fonseca, Francisco

    2010-05-01

    soil before and during the measurement. Due to the commonly found high variability, natural or induced by land management, of the soil surface and subsurface hydrological properties, and to the limitations imposed by the requirements of water for the measurements, there is proposed a simple and handy method, which do not use high volumes of water, adaptable to very different soil and land conditions, and that allow many repeated measurements with acceptable accuracy for most of the purposes. References Pla, I., 1997. A soil water balance model for monitoring soil erosion processes and effects on steep lands in the tropics. Soil Technology. 11(1):17-30. Elsevier Pla, I., 2006. Hydrological approach for assessing desertification processes in the Mediterranean region. In W.G. Kepner et al. (Editors), Desertification in the Mediterranean Region. A Security Issue. 579-600 Springer. Heidelberg (Germany) Reynolds W.D., B.T. Bowman, R.R. Brunke, C.F. Drury and C.S. Tan. 2000. Comparison of Tension Infiltrometer, Pressure Infiltrometer, and Soil Core Estimates of Saturated Hydraulic Conductivity . Soil Science Society of America Journal 64:478-484 Segal, E., S.A.Bradford, P. Shouse; N. Lazarovich, and D. Corwin. 2008. Integration of Hard and Soft Data to Characterize Field-Scale Hydraulic Properties for Flow and Transport Studies. Vadose Zone J 7:878-889 Young, E. 1991. Infiltration measurements, a review. Hydrological processes 5: 309-320.

  5. Advances in computational methods for Quantum Field Theory calculations

    NARCIS (Netherlands)

    Ruijl, B.J.G.

    2017-01-01

    In this work we describe three methods to improve the performance of Quantum Field Theory calculations. First, we simplify large expressions to speed up numerical integrations. Second, we design Forcer, a program for the reduction of four-loop massless propagator integrals. Third, we extend the R*

  6. The Diagonal Compression Field Method using Circular Fans

    DEFF Research Database (Denmark)

    Hansen, Thomas

    2006-01-01

    is a modification of the traditional method, the modification consisting of the introduction of circular fan stress fields. To ensure proper behaviour for the service load the -value ( = cot, where  is the angle relative to the beam axis of the uniaxial concrete compression) chosen should not be too large...

  7. Three-dimensional wake field analysis by boundary element method

    International Nuclear Information System (INIS)

    Miyata, K.

    1987-01-01

    A computer code HERTPIA was developed for the calculation of electromagnetic wake fields excited by charged particles travelling through arbitrarily shaped accelerating cavities. This code solves transient wave problems for a Hertz vector. The numerical analysis is based on the boundary element method. This program is validated by comparing its results with analytical solutions in a pill-box cavity

  8. General Anisotropy Identification of Paperboard with Virtual Fields Method

    Science.gov (United States)

    J.M. Considine; F. Pierron; K.T. Turner; D.W. Vahey

    2014-01-01

    This work extends previous efforts in plate bending of Virtual Fields Method (VFM) parameter identification to include a general 2-D anisotropicmaterial. Such an extension was needed for instances in which material principal directions are unknown or when specimen orientation is not aligned with material principal directions. A new fixture with a multiaxial force...

  9. SUBJECTIVE METHODS FOR ASSESSMENT OF DRIVER DROWSINESS

    Directory of Open Access Journals (Sweden)

    Alina Mashko

    2017-12-01

    Full Text Available The paper deals with the issue of fatigue and sleepiness behind the wheel, which for a long time has been of vital importance for the research in the area of driver-car interaction safety. Numerous experiments on car simulators with diverse measurements to observe human behavior have been performed at the laboratories of the faculty of the authors. The paper provides analysis and an overview and assessment of the subjective (self-rating and observer rating methods for observation of driver behavior and the detection of critical behavior in sleep deprived drivers using the developed subjective rating scales.

  10. Assessing Education Needs at Tertiary Level: The Focus Group Method

    Directory of Open Access Journals (Sweden)

    Elena-Mirela Samfira

    2015-10-01

    Full Text Available The goal of the paper is to point out the advantages and disadvantages of the focus group method in assessing the education needs of teachers and students in veterinary medicine. It is the first stage of a wider research aiming at developing problem-based teaching and learning methodologies in the field of veterinary medicine. The materials used consisted of literature documents on focus group as a research method in social sciences. The authors studied the literature available in the field and synthesised its main advantages and disadvantages. The paper is the first of this kind in Romania. Results show that there is no agreement yet on the advantages and disadvantages of this method. The research limitation is that there is almost no Romanian literature on focus group as a method. The usefulness of the paper is obvious: it allows other researchers in the field of education see the benefits of using such a research method. The originality of the paper consists in the fact that there has been no such research so far in Romanian higher education. Based on the results of the focus groups organised, the authors will design and implement a problem-based learning methodology for the students in veterinary medicine.

  11. An empirical method for dynamic camouflage assessment

    Science.gov (United States)

    Blitch, John G.

    2011-06-01

    As camouflage systems become increasingly sophisticated in their potential to conceal military personnel and precious cargo, evaluation methods need to evolve as well. This paper presents an overview of one such attempt to explore alternative methods for empirical evaluation of dynamic camouflage systems which aspire to keep pace with a soldier's movement through rapidly changing environments that are typical of urban terrain. Motivating factors are covered first, followed by a description of the Blitz Camouflage Assessment (BCA) process and results from an initial proof of concept experiment conducted in November 2006. The conclusion drawn from these results, related literature and the author's personal experience suggest that operational evaluation of personal camouflage needs to be expanded beyond its foundation in signal detection theory and embrace the challenges posed by high levels of cognitive processing.

  12. LCIA selection methods for assessing toxic releases

    DEFF Research Database (Denmark)

    Larsen, Henrik Fred; Birkved, Morten; Hauschild, Michael Zwicky

    2002-01-01

    the inventory that contribute significantly to the impact categories on ecotoxicity and human toxicity to focus the characterisation work. The reason why the selection methods are more important for the chemical-related impact categories than for other impact categories is the extremely high number......Characterization of toxic emissions in life cycle impact assessment (LCIA) is in many cases severely limited by the lack of characterization factors for the emissions mapped in the inventory. The number of substances assigned characterization factors for (eco)toxicity included in the dominating LCA....... The methods are evaluated against a set of pre-defined criteria (comprising consistency with characterization and data requirement) and applied to case studies and a test set of chemicals. The reported work is part of the EU-project OMNIITOX....

  13. Field Deployable Method for Arsenic Speciation in Water.

    Science.gov (United States)

    Voice, Thomas C; Flores Del Pino, Lisveth V; Havezov, Ivan; Long, David T

    2011-01-01

    Contamination of drinking water supplies by arsenic is a world-wide problem. Total arsenic measurements are commonly used to investigate and regulate arsenic in water, but it is well understood that arsenic occurs in several chemical forms, and these exhibit different toxicities. It is problematic to use laboratory-based speciation techniques to assess exposure as it has been suggested that the distribution of species is not stable during transport in some types of samples. A method was developed in this study for the on-site speciation of the most toxic dissolved arsenic species: As (III), As (V), monomethylarsonic acid (MMA) and dimethylarsenic acid (DMA). Development criteria included ease of use under field conditions, applicable at levels of concern for drinking water, and analytical performance.The approach is based on selective retention of arsenic species on specific ion-exchange chromatography cartridges followed by selective elution and quantification using graphite furnace atomic absorption spectroscopy. Water samples can be delivered to a set of three cartridges using either syringes or peristaltic pumps. Species distribution is stable at this point, and the cartridges can be transported to the laboratory for elution and quantitative analysis. A set of ten replicate spiked samples of each compound, having concentrations between 1 and 60 µg/L, were analyzed. Arsenic recoveries ranged from 78-112 % and relative standard deviations were generally below 10%. Resolution between species was shown to be outstanding, with the only limitation being that the capacity for As (V) was limited to approximately 50 µg/L. This could be easily remedied by changes in either cartridge design, or the extraction procedure. Recoveries were similar for two spiked hard groundwater samples indicating that dissolved minerals are not likely to be problematic. These results suggest that this methodology can be use for analysis of the four primary arsenic species of concern in

  14. Determination of the optimal method for the field-in-field technique in breast tangential radiotherapy

    International Nuclear Information System (INIS)

    Tanaka, Hidekazu; Hayashi, Shinya; Hoshi, Hiroaki

    2014-01-01

    Several studies have reported the usefulness of the field-in-field (FIF) technique in breast radiotherapy. However, the methods for the FIF technique used in these studies vary. These methods were classified into three categories. We simulated a radiotherapy plan with each method and analyzed the outcomes. In the first method, a pair of subfields was added to each main field: the single pair of subfields method (SSM). In the second method, three pairs of subfields were added to each main field: the multiple pairs of subfields method (MSM). In the third method, subfields were alternately added: the alternate subfields method (ASM). A total of 51 patients were enrolled in this study. The maximum dose to the planning target volume (PTV) (Dmax) and the volumes of the PTV receiving 100% of the prescription dose (V100%) were calculated. The thickness of the breast between the chest wall and skin surface was measured, and patients were divided into two groups according to the median. In the overall series, the average V100% with ASM (60.3%) was significantly higher than with SSM (52.6%) and MSM (48.7%). In the thin breast group as well, the average V100% with ASM (57.3%) and SSM (54.2%) was significantly higher than that with MSM (43.3%). In the thick breast group, the average V100% with ASM (63.4%) was significantly higher than that with SSM (51.0%) and MSM (54.4%). ASM resulted in better dose distribution, regardless of the breast size. Moreover, planning for ASM required a relatively short time. ASM was considered the most preferred method. (author)

  15. Four Methods for LIDAR Retrieval of Microscale Wind Fields

    Directory of Open Access Journals (Sweden)

    Thomas Naini

    2012-08-01

    Full Text Available This paper evaluates four wind retrieval methods for micro-scale meteorology applications with volume and time resolution in the order of 30m3 and 5 s. Wind field vectors are estimated using sequential time-lapse volume images of aerosol density fluctuations. Suitably designed mono-static scanning backscatter LIDAR systems, which are sensitive to atmospheric density aerosol fluctuations, are expected to be ideal for this purpose. An important application is wind farm siting and evaluation. In this case, it is necessary to look at the complicated region between the earth’s surface and the boundary layer, where wind can be turbulent and fractal scaling from millimeter to kilometer. The methods are demonstrated using first a simple randomized moving hard target, and then with a physics based stochastic space-time dynamic turbulence model. In the latter case the actual vector wind field is known, allowing complete space-time error analysis. Two of the methods, the semblance method and the spatio-temporal method, are found to be most suitable for wind field estimation.

  16. Multiresolution and Explicit Methods for Vector Field Analysis and Visualization

    Science.gov (United States)

    Nielson, Gregory M.

    1997-01-01

    This is a request for a second renewal (3d year of funding) of a research project on the topic of multiresolution and explicit methods for vector field analysis and visualization. In this report, we describe the progress made on this research project during the second year and give a statement of the planned research for the third year. There are two aspects to this research project. The first is concerned with the development of techniques for computing tangent curves for use in visualizing flow fields. The second aspect of the research project is concerned with the development of multiresolution methods for curvilinear grids and their use as tools for visualization, analysis and archiving of flow data. We report on our work on the development of numerical methods for tangent curve computation first.

  17. The Diagonal Compression Field Method using Circular Fans

    DEFF Research Database (Denmark)

    Hansen, Thomas

    2005-01-01

    This paper presents a new design method, which is a modification of the diagonal compression field method, the modification consisting of the introduction of circular fan stress fields. The traditional method does not allow changes of the concrete compression direction throughout a given beam...... if equilibrium is strictly required. This is conservative, since it is not possible fully to utilize the concrete strength in regions with low shear stresses. The larger inclination (the smaller -value) of the uniaxial concrete stress the more transverse shear reinforcement is needed; hence it would be optimal...... if the -value for a given beam could be set to a low value in regions with high shear stresses and thereafter increased in regions with low shear stresses. Thus the shear reinforcement would be reduced and the concrete strength would be utilized in a better way. In the paper it is shown how circular fan stress...

  18. Life cycle assessment in wastewater treatment: : Influence of site-oriented normalization factors, life cycle impact assessment methods, and weighting methods

    NARCIS (Netherlands)

    Bai, Shunwen; Wang, Xiuheng; Zhang, X.; Zhao, Xinyue; Ren, N

    2017-01-01

    This present study aims to analyze the differences in results of different site-directional life cycle assessment
    (LCA) methods applied in the field of wastewater treatment. Site-generic methods were employed and
    compared with China-specific methods on a full-scale wastewater treatment case.

  19. Method for solving quantum field theory in the Heisenberg picture

    International Nuclear Information System (INIS)

    Nakanishi, Noboru

    2004-01-01

    This paper is a review of the method for solving quantum field theory in the Heisenberg picture, developed by Abe and Nakanishi since 1991. Starting from field equations and canonical (anti) commutation relations, one sets up a (q-number) Cauchy problem for the totality of d-dimensional (anti) commutators between the fundamental fields, where d is the number of spacetime dimensions. Solving this Cauchy problem, one obtains the operator solution of the theory. Then one calculates all multiple commutators. A representation of the operator solution is obtained by constructing the set of all Wightman functions for the fundamental fields; the truncated Wightman functions are constructed so as to be consistent with all vacuum expectation values of the multiple commutators mentioned above and with the energy-positivity condition. By applying the method described above, exact solutions to various 2-dimensional gauge-theory and quantum-gravity models are found explicitly. The validity of these solutions is confirmed by comparing them with the conventional perturbation-theoretical results. However, a new anomalous feature, called the ''field-equation anomaly'', is often found to appear, and its perturbation-theoretical counterpart, unnoticed previously, is discussed. The conventional notion of an anomaly with respect to symmetry is reconsidered on the basis of the field-equation anomaly, and the derivation of the critical dimension in the BRS-formulated bosonic string theory is criticized. The method outlined above is applied to more realistic theories by expanding everything in powers of the relevant parameter, but this expansion is not equivalent to the conventional perturbative expansion. The new expansion is BRS-invariant at each order, in contrast to that in the conventional perturbation theory. Higher-order calculations are generally extremely laborious to perform explicitly. (author)

  20. Effective-field renormalization-group method for Ising systems

    Science.gov (United States)

    Fittipaldi, I. P.; De Albuquerque, D. F.

    1992-02-01

    A new applicable effective-field renormalization-group (ERFG) scheme for computing critical properties of Ising spins systems is proposed and used to study the phase diagrams of a quenched bond-mixed spin Ising model on square and Kagomé lattices. The present EFRG approach yields results which improves substantially on those obtained from standard mean-field renormalization-group (MFRG) method. In particular, it is shown that the EFRG scheme correctly distinguishes the geometry of the lattice structure even when working with the smallest possible clusters, namely N'=1 and N=2.

  1. Radio frequency electromagnetic field compliance assessment of multi-band and MIMO equipped radio base stations.

    Science.gov (United States)

    Thors, Björn; Thielens, Arno; Fridén, Jonas; Colombi, Davide; Törnevik, Christer; Vermeeren, Günter; Martens, Luc; Joseph, Wout

    2014-05-01

    In this paper, different methods for practical numerical radio frequency exposure compliance assessments of radio base station products were investigated. Both multi-band base station antennas and antennas designed for multiple input multiple output (MIMO) transmission schemes were considered. For the multi-band case, various standardized assessment methods were evaluated in terms of resulting compliance distance with respect to the reference levels and basic restrictions of the International Commission on Non-Ionizing Radiation Protection. Both single frequency and multiple frequency (cumulative) compliance distances were determined using numerical simulations for a mobile communication base station antenna transmitting in four frequency bands between 800 and 2600 MHz. The assessments were conducted in terms of root-mean-squared electromagnetic fields, whole-body averaged specific absorption rate (SAR) and peak 10 g averaged SAR. In general, assessments based on peak field strengths were found to be less computationally intensive, but lead to larger compliance distances than spatial averaging of electromagnetic fields used in combination with localized SAR assessments. For adult exposure, the results indicated that even shorter compliance distances were obtained by using assessments based on localized and whole-body SAR. Numerical simulations, using base station products employing MIMO transmission schemes, were performed as well and were in agreement with reference measurements. The applicability of various field combination methods for correlated exposure was investigated, and best estimate methods were proposed. Our results showed that field combining methods generally considered as conservative could be used to efficiently assess compliance boundary dimensions of single- and dual-polarized multicolumn base station antennas with only minor increases in compliance distances. © 2014 Wiley Periodicals, Inc.

  2. Analysis and Comparison of Objective Methods for Image Quality Assessment

    Directory of Open Access Journals (Sweden)

    P. S. Babkin

    2014-01-01

    Full Text Available The purpose of this work is research and modification of the reference objective methods for image quality assessment. The ultimate goal is to obtain a modification of formal assessments that more closely corresponds to the subjective expert estimates (MOS.In considering the formal reference objective methods for image quality assessment we used the results of other authors, which offer results and comparative analyzes of the most effective algorithms. Based on these investigations we have chosen two of the most successful algorithm for which was made a further analysis in the MATLAB 7.8 R 2009 a (PQS and MSSSIM. The publication focuses on the features of the algorithms, which have great importance in practical implementation, but are insufficiently covered in the publications by other authors.In the implemented modification of the algorithm PQS boundary detector Kirsch was replaced by the boundary detector Canny. Further experiments were carried out according to the method of the ITU-R VT.500-13 (01/2012 using monochrome images treated with different types of filters (should be emphasized that an objective assessment of image quality PQS is applicable only to monochrome images. Images were obtained with a thermal imaging surveillance system. The experimental results proved the effectiveness of this modification.In the specialized literature in the field of formal to evaluation methods pictures, this type of modification was not mentioned.The method described in the publication can be applied to various practical implementations of digital image processing.Advisability and effectiveness of using the modified method of PQS to assess the structural differences between the images are shown in the article and this will be used in solving the problems of identification and automatic control.

  3. ALARA ASSESSMENT OF SETTLER SLUDGE SAMPLING METHODS

    International Nuclear Information System (INIS)

    Nelsen, L.A.

    2009-01-01

    The purpose of this assessment is to compare underwater and above water settler sludge sampling methods to determine if the added cost for underwater sampling for the sole purpose of worker dose reductions is justified. Initial planning for sludge sampling included container, settler and knock-out-pot (KOP) sampling. Due to the significantly higher dose consequence of KOP sludge, a decision was made to sample KOP underwater to achieve worker dose reductions. Additionally, initial plans were to utilize the underwater sampling apparatus for settler sludge. Since there are no longer plans to sample KOP sludge, the decision for underwater sampling for settler sludge needs to be revisited. The present sampling plan calls for spending an estimated $2,500,000 to design and construct a new underwater sampling system (per A21 C-PL-001 RevOE). This evaluation will compare and contrast the present method of above water sampling to the underwater method that is planned by the Sludge Treatment Project (STP) and determine if settler samples can be taken using the existing sampling cart (with potentially minor modifications) while maintaining doses to workers As Low As Reasonably Achievable (ALARA) and eliminate the need for costly redesigns, testing and personnel retraining

  4. ALARA ASSESSMENT OF SETTLER SLUDGE SAMPLING METHODS

    Energy Technology Data Exchange (ETDEWEB)

    NELSEN LA

    2009-01-30

    The purpose of this assessment is to compare underwater and above water settler sludge sampling methods to determine if the added cost for underwater sampling for the sole purpose of worker dose reductions is justified. Initial planning for sludge sampling included container, settler and knock-out-pot (KOP) sampling. Due to the significantly higher dose consequence of KOP sludge, a decision was made to sample KOP underwater to achieve worker dose reductions. Additionally, initial plans were to utilize the underwater sampling apparatus for settler sludge. Since there are no longer plans to sample KOP sludge, the decision for underwater sampling for settler sludge needs to be revisited. The present sampling plan calls for spending an estimated $2,500,000 to design and construct a new underwater sampling system (per A21 C-PL-001 RevOE). This evaluation will compare and contrast the present method of above water sampling to the underwater method that is planned by the Sludge Treatment Project (STP) and determine if settler samples can be taken using the existing sampling cart (with potentially minor modifications) while maintaining doses to workers As Low As Reasonably Achievable (ALARA) and eliminate the need for costly redesigns, testing and personnel retraining.

  5. Process system and method for fabricating submicron field emission cathodes

    Science.gov (United States)

    Jankowski, Alan F.; Hayes, Jeffrey P.

    1998-01-01

    A process method and system for making field emission cathodes exists. The deposition source divergence is controlled to produce field emission cathodes with height-to-base aspect ratios that are uniform over large substrate surface areas while using very short source-to-substrate distances. The rate of hole closure is controlled from the cone source. The substrate surface is coated in well defined increments. The deposition source is apertured to coat pixel areas on the substrate. The entire substrate is coated using a manipulator to incrementally move the whole substrate surface past the deposition source. Either collimated sputtering or evaporative deposition sources can be used. The position of the aperture and its size and shape are used to control the field emission cathode size and shape.

  6. Methods for studying plasma charge transport across a magnetic field

    International Nuclear Information System (INIS)

    Popovich, A.S.

    1978-01-01

    A comparative analysis of experimental methods for the diffusion transfer of plasma charged particles accross the magnetic field at the study of its confinement effectiveness, instability effect is carried out. Considered are the methods based on the analysis of particle balance in the charge and possibilities of diffusion coefficient determination according to measuring parameters of density gradient and particle flow on the wall, rate of plasma decay after switching off ionization source radial profile of plasma density outside the active region of stationary charge. Much attension is payed to the research methods of diffusion transfer, connected with the study of propagation of periodic and aperiodic density perturbation in a plasma. Analysed is the Golubev and Granovsky method of diffusion waves and its different modifications, phase analysis method of ''test charges'' movement, as well as different modifications of correlation methods. Considered are physical preconditions of the latter and criticized is unilateral interpretation of correlation measurings, carried out in a number of works. The analysis of study possibilities of independent (non-ambipolar) diffusion of electrons and ions in a plasma in the magnetic field is executed

  7. The use of environmental assessments in the Brae field development

    International Nuclear Information System (INIS)

    Grogan, W.C.

    1991-01-01

    This paper reviews the principle environmental aspects associated with North Sea offshore oil and gas development and through the case history of Marathon Oil UK's Brae Field Development illustrates the scope and function of environmental assessments as applied to offshore developments. Details of the approach taken are described including the chronological evolution of the scope and aims of individual assessments. Examples of discharge inventory preparation, effluent and receiving environment monitoring programs, audits and inspections and procedures are described. The role of these components in the development of environmental management systems is discussed

  8. Methodology to Assess No Touch Audit Software Using Field Data

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Jie [Purdue Univ., West Lafayette, IN (United States); Braun, James E. [Purdue Univ., West Lafayette, IN (United States); Langner, M. Rois [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-10-01

    The research presented in this report builds upon these previous efforts and proposes a set of tests to assess no touch audit tools using real utility bill and on-site data. The proposed assessment methodology explicitly investigates the behaviors of the monthly energy end uses with respect to outdoor temperature, i.e., the building energy signature, to help understand the Tool's disaggregation accuracy. The project team collaborated with Field Diagnosis Services, Inc. (FDSI) to identify appropriate test sites for the evaluation.

  9. Problems of method of technology assessment

    International Nuclear Information System (INIS)

    Zimmermann, V.

    1993-03-01

    The study undertakes to analyse the theoretical and methodological structure of Technology Assessment (TA). It is based on a survey of TA studies which provided an important condition for theoreticall sound statements on methodological aspects of TA. It was established that the main basic theoretical problems of TA are in the field of dealing with complexity. This is also apparent in the constitution of problems, the most elementary and central approach of TA. Scientifically founded constitution of problems and the corresponding construction of models call for interdisciplinary scientific work. Interdisciplinarity in the TA research process is achieved at the level of virtual networks, these networks being composed of individuals suited to teamwork. The emerging network structures have an objective-organizational and an ideational basis. The objective-organizational basis is mainly the result of team composition and the external affiliations of the team members. The ideational basis of the virtual network is represented by the team members' mode of thinking, which is individually located at a multidisciplinary level. The theoretical 'skeleton' of the TA knowledge system, which is represented by process knowledge based linkage structures, can be generated and also processed in connection with the knowledge on types of problems, areas of analysis and procedures to deal with complexity. Within this process, disciplinary knowledge is a necessary but not a sufficient condition. Metatheoretical and metadisciplinary knowledge and the correspondingly processes complexity of models are the basis for the necessary methodological awareness, that allows TA to become designable as a research procedure. (orig./HP) [de

  10. Assessing wine quality using isotopic methods

    International Nuclear Information System (INIS)

    Costinel, Diana; Ionete, Roxana Elena; Vremera, Raluca; Stefanescu, Ioan

    2010-01-01

    Full text: The analytical methods used to determine the isotope ratios of deuterium, carbon-13 and oxygen-18 in wines have gained official recognition from the Office International de la Vigne et du Vin (OIV) and National Organisation of Vine and Wine. The amount of stable isotopes in water and carbon dioxide from plant organic materials and their distribution in sugar and ethanol molecules are influenced by geo-climatic conditions of the region, grape varieties and the year of harvest. For wine characterization, to prove the botanical and geographical origin of the raw material, the isotopic analysis by continuous flow mass spectrometry CF-IRMS has made a significant contribution. This paper emphasize the results of a study concerning the assessing of water adulterated wines and non-grape alcohol and sugar additions at different concentration levels, using CF-IRMS analytical technique. (authors)

  11. Elastic wave scattering methods: assessments and suggestions

    International Nuclear Information System (INIS)

    Gubernatis, J.E.

    1985-01-01

    The author was asked by the meeting organizers to review and assess the developments over the past ten or so years in elastic wave scattering methods and to suggest areas of future research opportunities. He highlights the developments, focusing on what he feels were distinct steps forward in our theoretical understanding of how elastic waves interact with flaws. For references and illustrative figures, he decided to use as his principal source the proceedings of the various annual Reviews of Progress in Quantitative Nondestructive Evaluation (NDE). These meetings have been the main forum not only for presenting results of theoretical research but also for demonstrating the relevance of the theoretical research for the design and interpretation of experiment. In his opinion a quantitative NDE is possible only if this relevance exists, and his major objective is to discuss and illustrate the degree to which relevance has developed

  12. The reduced basis method for the electric field integral equation

    International Nuclear Information System (INIS)

    Fares, M.; Hesthaven, J.S.; Maday, Y.; Stamm, B.

    2011-01-01

    We introduce the reduced basis method (RBM) as an efficient tool for parametrized scattering problems in computational electromagnetics for problems where field solutions are computed using a standard Boundary Element Method (BEM) for the parametrized electric field integral equation (EFIE). This combination enables an algorithmic cooperation which results in a two step procedure. The first step consists of a computationally intense assembling of the reduced basis, that needs to be effected only once. In the second step, we compute output functionals of the solution, such as the Radar Cross Section (RCS), independently of the dimension of the discretization space, for many different parameter values in a many-query context at very little cost. Parameters include the wavenumber, the angle of the incident plane wave and its polarization.

  13. A geologic approach to field methods in fluvial geomorphology

    Science.gov (United States)

    Fitzpatrick, Faith A.; Thornbush, Mary J; Allen, Casey D; Fitzpatrick, Faith A.

    2014-01-01

    A geologic approach to field methods in fluvial geomorphology is useful for understanding causes and consequences of past, present, and possible future perturbations in river behavior and floodplain dynamics. Field methods include characterizing river planform and morphology changes and floodplain sedimentary sequences over long periods of time along a longitudinal river continuum. Techniques include topographic and bathymetric surveying of fluvial landforms in valley bottoms and describing floodplain sedimentary sequences through coring, trenching, and examining pits and exposures. Historical sediment budgets that include floodplain sedimentary records can characterize past and present sources and sinks of sediment along a longitudinal river continuum. Describing paleochannels and floodplain vertical accretion deposits, estimating long-term sedimentation rates, and constructing historical sediment budgets can assist in management of aquatic resources, habitat, sedimentation, and flooding issues.

  14. Modeling Enzymatic Transition States by Force Field Methods

    DEFF Research Database (Denmark)

    Hansen, Mikkel Bo; Jensen, Hans Jørgen Aagaard; Jensen, Frank

    2009-01-01

    The SEAM method, which models a transition structure as a minimum on the seam of two diabatic surfaces represented by force field functions, has been used to generate 20 transition structures for the decarboxylation of orotidine by the orotidine-5'-monophosphate decarboxylase enzyme. The dependence...... of the TS geometry on the flexibility of the system has been probed by fixing layers of atoms around the active site and using increasingly larger nonbonded cutoffs. The variability over the 20 structures is found to decrease as the system is made more flexible. Relative energies have been calculated...... by various electronic structure methods, where part of the enzyme is represented by a force field description and the effects of the solvent are represented by a continuum model. The relative energies vary by several hundreds of kJ/mol between the transition structures, and tests showed that a large part...

  15. Method for imaging with low frequency electromagnetic fields

    Science.gov (United States)

    Lee, Ki H.; Xie, Gan Q.

    1994-01-01

    A method for imaging with low frequency electromagnetic fields, and for interpreting the electromagnetic data using ray tomography, in order to determine the earth conductivity with high accuracy and resolution. The imaging method includes the steps of placing one or more transmitters, at various positions in a plurality of transmitter holes, and placing a plurality of receivers in a plurality of receiver holes. The transmitters generate electromagnetic signals which diffuse through a medium, such as earth, toward the receivers. The measured diffusion field data H is then transformed into wavefield data U. The traveltimes corresponding to the wavefield data U, are then obtained, by charting the wavefield data U, using a different regularization parameter .alpha. for each transform. The desired property of the medium, such as conductivity, is then derived from the velocity, which in turn is constructed from the wavefield data U using ray tomography.

  16. Multi-phase-field method for surface tension induced elasticity

    Science.gov (United States)

    Schiedung, Raphael; Steinbach, Ingo; Varnik, Fathollah

    2018-01-01

    A method, based on the multi-phase-field framework, is proposed that adequately accounts for the effects of a coupling between surface free energy and elastic deformation in solids. The method is validated via a number of analytically solvable problems. In addition to stress states at mechanical equilibrium in complex geometries, the underlying multi-phase-field framework naturally allows us to account for the influence of surface energy induced stresses on phase transformation kinetics. This issue, which is of fundamental importance on the nanoscale, is demonstrated in the limit of fast diffusion for a solid sphere, which melts due to the well-known Gibbs-Thompson effect. This melting process is slowed down when coupled to surface energy induced elastic deformation.

  17. Objective Assessment Method for RNAV STAR Adherence

    Science.gov (United States)

    Stewart, Michael; Matthews, Bryan

    2017-01-01

    Flight crews and air traffic controllers have reported many safety concerns regarding area navigation standard terminal arrival routes (RNAV STARs). Specifically, optimized profile descents (OPDs). However, our information sources to quantify these issues are limited to subjective reporting and time consuming case-by-case investigations. This work is a preliminary study into the objective performance of instrument procedures and provides a framework to track procedural concepts and assess design specifications. We created a tool and analysis methods for gauging aircraft adherence as it relates to RNAV STARs. This information is vital for comprehensive understanding of how our air traffic behaves. In this study, we mined the performance of 24 major US airports over the preceding three years. Overlaying 4D radar track data onto RNAV STAR routes provided a comparison between aircraft flight paths and the waypoint positions and altitude restrictions. NASA Ames Supercomputing resources were utilized to perform the data mining and processing. We assessed STARs by lateral transition path (full-lateral), vertical restrictions (full-lateral/full-vertical), and skipped waypoints (skips). In addition, we graphed frequencies of aircraft altitudes relative to the altitude restrictions. Full-lateral adherence was always greater than Full-lateral/ full- vertical, as it is a subset, but the difference between the rates was not consistent. Full-lateral/full-vertical adherence medians of the 2016 procedures ranged from 0% in KDEN (Denver) to 21% in KMEM (Memphis). Waypoint skips ranged from 0% to nearly 100% for specific waypoints. Altitudes restrictions were sometimes missed by systematic amounts in 1,000 ft. increments from the restriction, creating multi-modal distributions. Other times, altitude misses looked to be more normally distributed around the restriction. This tool may aid in providing acceptability metrics as well as risk assessment information.

  18. An Improved Image Contrast Assessment Method

    Directory of Open Access Journals (Sweden)

    Yuanyuan Fan

    2013-07-01

    Full Text Available Contrast is an important factor affecting the image quality. In order to overcome the problems of local band-limited contrast, a novel image contrast assessment method based on the property of HVS is proposed. Firstly, the image by low-pass filter is performed fast wavelet decomposition. Secondly, all levels of band-pass filtered image and its corresponding low-pass filtered image are obtained by processing wavelet coefficients. Thirdly, local band-limited contrast is calculated, and the local band-limited contrast entropy is calculated according to the definition of entropy, Finally, the contrast entropy of image is obtained by averaging the local band-limited contrast entropy weighed using CSF coefficient. The experiment results show that the best contrast image can be accurately identified in the sequence images obtained by adjusting the exposure time and stretching gray respectively, the assessment results accord with human visual characteristics and make up the lack of local band-limited contrast.

  19. The virtual fields method applied to spalling tests on concrete

    Directory of Open Access Journals (Sweden)

    Forquin P.

    2012-08-01

    Full Text Available For one decade spalling techniques based on the use of a metallic Hopkinson bar put in contact with a concrete sample have been widely employed to characterize the dynamic tensile strength of concrete at strain-rates ranging from a few tens to two hundreds of s−1. However, the processing method mainly based on the use of the velocity profile measured on the rear free surface of the sample (Novikov formula remains quite basic and an identification of the whole softening behaviour of the concrete is out of reach. In the present paper a new processing method is proposed based on the use of the Virtual Fields Method (VFM. First, a digital high speed camera is used to record the pictures of a grid glued on the specimen. Next, full-field measurements are used to obtain the axial displacement field at the surface of the specimen. Finally, a specific virtual field has been defined in the VFM equation to use the acceleration map as an alternative ‘load cell’. This method applied to three spalling tests allowed to identify Young’s modulus during the test. It was shown that this modulus is constant during the initial compressive part of the test and decreases in the tensile part when micro-damage exists. It was also shown that in such a simple inertial test, it was possible to reconstruct average axial stress profiles using only the acceleration data. Then, it was possible to construct local stress-strain curves and derive a tensile strength value.

  20. Method of a covering space in quantum field theory

    International Nuclear Information System (INIS)

    Serebryanyj, E.M.

    1982-01-01

    To construct the Green function of the Laplace operator in the domain M bounded by conducting surfaces the generalized method of images is used. It is based on replacement of the domain M by its discrete bundle and that is why the term ''method of covering space'' is used. Continuing one of the coordinates to imaginary values the euclidean Green function is transformed into the causal one. This allows one to compute vacuum stress-energy tensor of the scalar massless field if the vacuum is stable [ru

  1. Investigation of drag effect using the field signature method

    International Nuclear Information System (INIS)

    Wan, Zhengjun; Liao, Junbi; Tian, Gui Yun; Cheng, Liang

    2011-01-01

    The potential drop (PD) method is an established non-destructive evaluation (NDE) technique. The monitoring of internal corrosion, erosion and cracks in piping systems, based on electrical field mapping or direct current potential drop array, is also known as the field signature method (FSM). The FSM has been applied in the field of submarine pipe monitoring and land-based oil and gas transmission pipes and containers. In the experimental studies, to detect and calculate the degree of pipe corrosion, the FSM analyses the relationships between the electrical resistance and pipe thickness using an electrode matrix. The relevant drag effect or trans-resistance will cause a large margin of error in the application of resistance arrays. It is the first time that the drag effect in the paper is investigated and analysed in resistance networks with the help of the FSM. Subsequently, a method to calculate the drag factors and eliminate its errors is proposed and presented. Theoretical analysis, simulation and experimental results show that the measurement accuracy can be improved by eliminating the errors caused by the drag effect

  2. Rapid assessment of rice seed availability for wildlife in harvested fields

    Science.gov (United States)

    Halstead, B.J.; Miller, M.R.; Casazza, Michael L.; Coates, P.S.; Farinha, M.A.; Benjamin, Gustafson K.; Yee, J.L.; Fleskes, J.P.

    2011-01-01

    Rice seed remaining in commercial fields after harvest (waste rice) is a critical food resource for wintering waterfowl in rice-growing regions of North America. Accurate and precise estimates of the seed mass density of waste rice are essential for planning waterfowl wintering habitat extents and management. In the Sacramento Valley of California, USA, the existing method for obtaining estimates of availability of waste rice in harvested fields produces relatively precise estimates, but the labor-, time-, and machineryintensive process is not practical for routine assessments needed to examine long-term trends in waste rice availability. We tested several experimental methods designed to rapidly derive estimates that would not be burdened with disadvantages of the existing method. We first conducted a simulation study of the efficiency of each method and then conducted field tests. For each approach, methods did not vary in root mean squared error, although some methods did exhibit bias for both simulations and field tests. Methods also varied substantially in the time to conduct each sample and in the number of samples required to detect a standard trend. Overall, modified line-intercept methods performed well for estimating the density of rice seeds. Waste rice in the straw, although not measured directly, can be accounted for by a positive relationship with density of rice on the ground. Rapid assessment of food availability is a useful tool to help waterfowl managers establish and implement wetland restoration and agricultural habitat-enhancement goals for wintering waterfowl. ?? 2011 The Wildlife Society.

  3. Field investigation to assess nutrient emission from paddy field to surface water in river catchment

    Science.gov (United States)

    Kogure, Kanami; Aichi, Masaatsu; Zessner, Matthias

    2015-04-01

    In order to maintain good river environment, it is remarkably important to understand and to control nutrient behavior such as Nitrogen and Phosphorus. Our former research dealing with nutrient emission analysis in the Tone River basin area in Japan, in addition to urban and industrial waste water, nutrient emission from agricultural activity is dominant pollution source into the river system. Japanese style agriculture produces large amount of rice and paddy field occupies large areas in Japanese river basin areas. While paddy field can deteriorate river water quality by outflow of fertilizer, it is also suggested that paddy field has water purification function. As we carried out investigation in the Tone River Basin area, data were obtained which dissolved nitrogen concentration is lower in discharging water from paddy field than inflowing water into the field. Regarding to nutrient emission impact from paddy field, sufficient data are required to discuss quantitatively seasonal change of material behavior including flooding season and dry season, difference of climate condition, soil type, and rice species, to evaluate year round comprehensive impact from paddy field to the river system. In this research, field survey in paddy field and data collection relating rice production were carried out as a preliminary investigation to assess how Japanese style paddy field contributes year round on surface water quality. Study sites are three paddy fields located in upper reach of the Tone River basin area. The fields are flooded from June to September. In 2014, field investigations were carried out three times in flooding period and twice in dry period. To understand characteristics of each paddy field and seasonal tendency accompanying weather of agricultural event, short term investigations were conducted and we prepare for further long term investigation. Each study site has irrigation water inflow and outflow. Two sites have tile drainage system under the field and

  4. Assessment of multiple frequency ELF electric and magnetic field exposure

    International Nuclear Information System (INIS)

    Leitgeb, N

    2008-01-01

    Electromagnetic fields both in daily life and at workplaces exhibit increasingly complex frequency spectra. Present spectral assessment rules proved to be too conservative for health risk assessment. This is because they are based on the assumption that cells would react like linear systems in terms of responding to a sum of frequencies by a sum of independent responses to each individual frequency. Based on numerical investigations with the Hodgkin-Huxley and the Frankenhaeuser-Huxley nerve cell models, it could be shown that accounting for the nonlinear behaviour of cellular excitation processes avoids considerable overestimation of simultaneous exposures to multiple frequency ELF electric and magnetic fields. Besides this, it could be shown that the role of phase relationships is less important than that assumed so far. The present assessment rules lead to non-compliances of marketed electric appliances. For general application, a nonlinear biology-based assessment (NBBA) rule has been proposed, validated and proven advantageous compared with ICNIRP's rule. While staying conservative it avoids unnecessary overestimation and demonstrates compliance even in cases of suspected non-conformities. It is up to responsible bodies to decide upon the adoption of this proposal and the potential need for implementing additional or reducing the already incorporated safety factors

  5. Field Sample Preparation Method Development for Isotope Ratio Mass Spectrometry

    International Nuclear Information System (INIS)

    Leibman, C.; Weisbrod, K.; Yoshida, T.

    2015-01-01

    Non-proliferation and International Security (NA-241) established a working group of researchers from Los Alamos National Laboratory (LANL), Pacific Northwest National Laboratory (PNNL) and Savannah River National Laboratory (SRNL) to evaluate the utilization of in-field mass spectrometry for safeguards applications. The survey of commercial off-the-shelf (COTS) mass spectrometers (MS) revealed no instrumentation existed capable of meeting all the potential safeguards requirements for performance, portability, and ease of use. Additionally, fieldable instruments are unlikely to meet the International Target Values (ITVs) for accuracy and precision for isotope ratio measurements achieved with laboratory methods. The major gaps identified for in-field actinide isotope ratio analysis were in the areas of: 1. sample preparation and/or sample introduction, 2. size reduction of mass analyzers and ionization sources, 3. system automation, and 4. decreased system cost. Development work in 2 through 4, numerated above continues, in the private and public sector. LANL is focusing on developing sample preparation/sample introduction methods for use with the different sample types anticipated for safeguard applications. Addressing sample handling and sample preparation methods for MS analysis will enable use of new MS instrumentation as it becomes commercially available. As one example, we have developed a rapid, sample preparation method for dissolution of uranium and plutonium oxides using ammonium bifluoride (ABF). ABF is a significantly safer and faster alternative to digestion with boiling combinations of highly concentrated mineral acids. Actinides digested with ABF yield fluorides, which can then be analyzed directly or chemically converted and separated using established column chromatography techniques as needed prior to isotope analysis. The reagent volumes and the sample processing steps associated with ABF sample digestion lend themselves to automation and field

  6. Evaluation of methods to assess physical activity

    Science.gov (United States)

    Leenders, Nicole Y. J. M.

    Epidemiological evidence has accumulated that demonstrates that the amount of physical activity-related energy expenditure during a week reduces the incidence of cardiovascular disease, diabetes, obesity, and all-cause mortality. To further understand the amount of daily physical activity and related energy expenditure that are necessary to maintain or improve the functional health status and quality of life, instruments that estimate total (TDEE) and physical activity-related energy expenditure (PAEE) under free-living conditions should be determined to be valid and reliable. Without evaluation of the various methods that estimate TDEE and PAEE with the doubly labeled water (DLW) method in females there will be eventual significant limitations on assessing the efficacy of physical activity interventions on health status in this population. A triaxial accelerometer (Tritrac-R3D, (TT)), an uniaxial (Computer Science and Applications Inc., (CSA)) activity monitor, a Yamax-Digiwalker-500sp°ler , (YX-stepcounter), by measuring heart rate responses (HR method) and a 7-d Physical Activity Recall questionnaire (7-d PAR) were compared with the "criterion method" of DLW during a 7-d period in female adults. The DLW-TDEE was underestimated on average 9, 11 and 15% using 7-d PAR, HR method and TT. The underestimation of DLW-PAEE by 7-d PAR was 21% compared to 47% and 67% for TT and YX-stepcounter. Approximately 56% of the variance in DLW-PAEE*kgsp{-1} is explained by the registration of body movement with accelerometry. A larger proportion of the variance in DLW-PAEE*kgsp{-1} was explained by jointly incorporating information from the vertical and horizontal movement measured with the CSA and Tritrac-R3D (rsp2 = 0.87). Although only a small amount of variance in DLW-PAEE*kgsp{-1} is explained by the number of steps taken per day, because of its low cost and ease of use, the Yamax-stepcounter is useful in studies promoting daily walking. Thus, studies involving the

  7. Grassmann phase space methods for fermions. II. Field theory

    Energy Technology Data Exchange (ETDEWEB)

    Dalton, B.J., E-mail: bdalton@swin.edu.au [Centre for Quantum and Optical Science, Swinburne University of Technology, Melbourne, Victoria 3122 (Australia); Jeffers, J. [Department of Physics, University of Strathclyde, Glasgow G4ONG (United Kingdom); Barnett, S.M. [School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom)

    2017-02-15

    In both quantum optics and cold atom physics, the behaviour of bosonic photons and atoms is often treated using phase space methods, where mode annihilation and creation operators are represented by c-number phase space variables, with the density operator equivalent to a distribution function of these variables. The anti-commutation rules for fermion annihilation, creation operators suggests the possibility of using anti-commuting Grassmann variables to represent these operators. However, in spite of the seminal work by Cahill and Glauber and a few applications, the use of Grassmann phase space methods in quantum-atom optics to treat fermionic systems is rather rare, though fermion coherent states using Grassmann variables are widely used in particle physics. This paper presents a phase space theory for fermion systems based on distribution functionals, which replace the density operator and involve Grassmann fields representing anti-commuting fermion field annihilation, creation operators. It is an extension of a previous phase space theory paper for fermions (Paper I) based on separate modes, in which the density operator is replaced by a distribution function depending on Grassmann phase space variables which represent the mode annihilation and creation operators. This further development of the theory is important for the situation when large numbers of fermions are involved, resulting in too many modes to treat separately. Here Grassmann fields, distribution functionals, functional Fokker–Planck equations and Ito stochastic field equations are involved. Typical applications to a trapped Fermi gas of interacting spin 1/2 fermionic atoms and to multi-component Fermi gases with non-zero range interactions are presented, showing that the Ito stochastic field equations are local in these cases. For the spin 1/2 case we also show how simple solutions can be obtained both for the untrapped case and for an optical lattice trapping potential.

  8. Grassmann phase space methods for fermions. II. Field theory

    International Nuclear Information System (INIS)

    Dalton, B.J.; Jeffers, J.; Barnett, S.M.

    2017-01-01

    In both quantum optics and cold atom physics, the behaviour of bosonic photons and atoms is often treated using phase space methods, where mode annihilation and creation operators are represented by c-number phase space variables, with the density operator equivalent to a distribution function of these variables. The anti-commutation rules for fermion annihilation, creation operators suggests the possibility of using anti-commuting Grassmann variables to represent these operators. However, in spite of the seminal work by Cahill and Glauber and a few applications, the use of Grassmann phase space methods in quantum-atom optics to treat fermionic systems is rather rare, though fermion coherent states using Grassmann variables are widely used in particle physics. This paper presents a phase space theory for fermion systems based on distribution functionals, which replace the density operator and involve Grassmann fields representing anti-commuting fermion field annihilation, creation operators. It is an extension of a previous phase space theory paper for fermions (Paper I) based on separate modes, in which the density operator is replaced by a distribution function depending on Grassmann phase space variables which represent the mode annihilation and creation operators. This further development of the theory is important for the situation when large numbers of fermions are involved, resulting in too many modes to treat separately. Here Grassmann fields, distribution functionals, functional Fokker–Planck equations and Ito stochastic field equations are involved. Typical applications to a trapped Fermi gas of interacting spin 1/2 fermionic atoms and to multi-component Fermi gases with non-zero range interactions are presented, showing that the Ito stochastic field equations are local in these cases. For the spin 1/2 case we also show how simple solutions can be obtained both for the untrapped case and for an optical lattice trapping potential.

  9. Assessing Asphalt and Concrete Pavement Surface Texture in the Field

    Directory of Open Access Journals (Sweden)

    Saad I. Sarsam

    2016-06-01

    Full Text Available The incorporation of safety characteristics into the traditional pavement structural design or in the functional evaluation of pavement condition has not been established yet. The design has focused on the structural capacity of the roadway so that the pavement can withstand specific level of repetitive loading over the design life. On the other hand, the surface texture condition was neither included in the AASHTO design procedure nor in the present serviceability index measurements. The pavement surface course should provide adequate levels of friction and ride quality and maintain low levels of noise and roughness. Many transportation departments perform routine skid resistant testing, the type of equipment used for testing varies depending on the preference of each transportation department. It was felt that modeling of the surface texture condition using different methods of testing may assist in solving such problem. In this work, Macro texture and Micro texture of asphalt and cement concrete pavement surface have been investigated in the field using four different methods (The Sand Patch Method, Outflow Time Method, British Pendulum Tester and Photogrammetry Technique. Two different grain sizes of sand have been utilized in conducting the Sand Patch while the Micro texture was investigated using the British Pendulum tester method at wet pavement surface conditions. The test results of the four methods were correlated to the skid number. It was concluded that such modeling could provide instant data in the field for pavement condition which may help in pavement maintenance management.

  10. Field evaluation of personal sampling methods for multiple bioaerosols.

    Science.gov (United States)

    Wang, Chi-Hsun; Chen, Bean T; Han, Bor-Cheng; Liu, Andrew Chi-Yeu; Hung, Po-Chen; Chen, Chih-Yong; Chao, Hsing Jasmine

    2015-01-01

    Ambient bioaerosols are ubiquitous in the daily environment and can affect health in various ways. However, few studies have been conducted to comprehensively evaluate personal bioaerosol exposure in occupational and indoor environments because of the complex composition of bioaerosols and the lack of standardized sampling/analysis methods. We conducted a study to determine the most efficient collection/analysis method for the personal exposure assessment of multiple bioaerosols. The sampling efficiencies of three filters and four samplers were compared. According to our results, polycarbonate (PC) filters had the highest relative efficiency, particularly for bacteria. Side-by-side sampling was conducted to evaluate the three filter samplers (with PC filters) and the NIOSH Personal Bioaerosol Cyclone Sampler. According to the results, the Button Aerosol Sampler and the IOM Inhalable Dust Sampler had the highest relative efficiencies for fungi and bacteria, followed by the NIOSH sampler. Personal sampling was performed in a pig farm to assess occupational bioaerosol exposure and to evaluate the sampling/analysis methods. The Button and IOM samplers yielded a similar performance for personal bioaerosol sampling at the pig farm. However, the Button sampler is more likely to be clogged at high airborne dust concentrations because of its higher flow rate (4 L/min). Therefore, the IOM sampler is a more appropriate choice for performing personal sampling in environments with high dust levels. In summary, the Button and IOM samplers with PC filters are efficient sampling/analysis methods for the personal exposure assessment of multiple bioaerosols.

  11. Field evaluation of personal sampling methods for multiple bioaerosols.

    Directory of Open Access Journals (Sweden)

    Chi-Hsun Wang

    Full Text Available Ambient bioaerosols are ubiquitous in the daily environment and can affect health in various ways. However, few studies have been conducted to comprehensively evaluate personal bioaerosol exposure in occupational and indoor environments because of the complex composition of bioaerosols and the lack of standardized sampling/analysis methods. We conducted a study to determine the most efficient collection/analysis method for the personal exposure assessment of multiple bioaerosols. The sampling efficiencies of three filters and four samplers were compared. According to our results, polycarbonate (PC filters had the highest relative efficiency, particularly for bacteria. Side-by-side sampling was conducted to evaluate the three filter samplers (with PC filters and the NIOSH Personal Bioaerosol Cyclone Sampler. According to the results, the Button Aerosol Sampler and the IOM Inhalable Dust Sampler had the highest relative efficiencies for fungi and bacteria, followed by the NIOSH sampler. Personal sampling was performed in a pig farm to assess occupational bioaerosol exposure and to evaluate the sampling/analysis methods. The Button and IOM samplers yielded a similar performance for personal bioaerosol sampling at the pig farm. However, the Button sampler is more likely to be clogged at high airborne dust concentrations because of its higher flow rate (4 L/min. Therefore, the IOM sampler is a more appropriate choice for performing personal sampling in environments with high dust levels. In summary, the Button and IOM samplers with PC filters are efficient sampling/analysis methods for the personal exposure assessment of multiple bioaerosols.

  12. Comparison between Evapotranspiration Fluxes Assessment Methods

    Science.gov (United States)

    Casola, A.; Longobardi, A.; Villani, P.

    2009-11-01

    Knowledge of hydrological processes acting in the water balance is determinant for a rational water resources management plan. Among these, the water losses as vapour, in the form of evapotranspiration, play an important role in the water balance and the heat transfers between the land surface and the atmosphere. Mass and energy interactions between soil, atmosphere and vegetation, in fact, influence all hydrological processes modificating rainfall interception, infiltration, evapotraspiration, surface runoff and groundwater recharge.A numbers of methods have been developed in scientific literature for modelling evapotranspiration. They can be divided in three main groups: i) traditional meteorological models, ii) energy fluxes balance models, considering interaction between vegetation and the atmosphere, and iii) remote sensing based models. The present analysis preliminary performs a study of fluxes directions and an evaluation of energy balance closure in a typical Mediterranean short vegetation area, using data series recorded from an eddy covariance station, located in the Campania region, Southern Italy. The analysis was performed on different seasons of the year with the aim to assess climatic forcing features impact on fluxes balance, to evaluate the smaller imbalance and to highlight influencing factors and sampling errors on balance closure. The present study also concerns evapotranspiration fluxes assessment at the point scale. Evapotranspiration is evaluated both from empirical relationships (Penmann-Montheit, Penmann F AO, Prestley&Taylor) calibrated with measured energy fluxes at mentioned experimental site, and from measured latent heat data scaled by the latent heat of vaporization. These results are compared with traditional and reliable well known models at the plot scale (Coutagne, Turc, Thorthwaite).

  13. Field Methods for the Study of Slope and Fluvial Processes

    Science.gov (United States)

    Leopold, Luna Bergere; Leopold, Luna Bergere

    1967-01-01

    In Belgium during the summer of 1966 the Commission on Slopes and the Commission on Applied Geomorphology of the International Geographical Union sponsored a joint symposium, with field excursions, and meetings of the two commissions. As a result of the conference and associated discussions, the participants expressed the view that it would be a contribution to scientific work relating to the subject area if the Commission on Applied Geomorphology could prepare a small manual describling the methods of field investigation being used by research scientists throughout the world in the study of various aspects of &lope development and fluvial processes. The Commission then assumed this responsibility and asked as many persons as were known to be. working on this subject to contribute whatever they wished in the way of descriptions of methods being employed.The purpose of the present manual is to show the variety of study methods now in use, to describe from the experience gained the limitations and advantages of different techniques, and to give pertinent detail which might be useful to other investigators. Some details that would be useful to know are not included in scientific publications, but in a manual on methods the details of how best t6 use a method has a place. Various persons have learned certain things which cannot be done, as well as some methods that are successful. It is our hope that comparison of methods tried will give the reader suggestions as to how a particular method might best be applied to his own circumstance.The manual does not purport to include methods used by all workers. In particular, it does not interfere with a more systematic treatment of the subject (1) or with various papers already published in the present journal. In fact we are sure that there are pertinent research methods that we do not know of and the Commission would be glad to receive additions and other ideas from those who find they have something to contribute. Also, the

  14. Hamiltonian lattice field theory: Computer calculations using variational methods

    International Nuclear Information System (INIS)

    Zako, R.L.

    1991-01-01

    I develop a variational method for systematic numerical computation of physical quantities -- bound state energies and scattering amplitudes -- in quantum field theory. An infinite-volume, continuum theory is approximated by a theory on a finite spatial lattice, which is amenable to numerical computation. I present an algorithm for computing approximate energy eigenvalues and eigenstates in the lattice theory and for bounding the resulting errors. I also show how to select basis states and choose variational parameters in order to minimize errors. The algorithm is based on the Rayleigh-Ritz principle and Kato's generalizations of Temple's formula. The algorithm could be adapted to systems such as atoms and molecules. I show how to compute Green's functions from energy eigenvalues and eigenstates in the lattice theory, and relate these to physical (renormalized) coupling constants, bound state energies and Green's functions. Thus one can compute approximate physical quantities in a lattice theory that approximates a quantum field theory with specified physical coupling constants. I discuss the errors in both approximations. In principle, the errors can be made arbitrarily small by increasing the size of the lattice, decreasing the lattice spacing and computing sufficiently long. Unfortunately, I do not understand the infinite-volume and continuum limits well enough to quantify errors due to the lattice approximation. Thus the method is currently incomplete. I apply the method to real scalar field theories using a Fock basis of free particle states. All needed quantities can be calculated efficiently with this basis. The generalization to more complicated theories is straightforward. I describe a computer implementation of the method and present numerical results for simple quantum mechanical systems

  15. Hamiltonian lattice field theory: Computer calculations using variational methods

    International Nuclear Information System (INIS)

    Zako, R.L.

    1991-01-01

    A variational method is developed for systematic numerical computation of physical quantities-bound state energies and scattering amplitudes-in quantum field theory. An infinite-volume, continuum theory is approximated by a theory on a finite spatial lattice, which is amenable to numerical computation. An algorithm is presented for computing approximate energy eigenvalues and eigenstates in the lattice theory and for bounding the resulting errors. It is shown how to select basis states and choose variational parameters in order to minimize errors. The algorithm is based on the Rayleigh-Ritz principle and Kato's generalizations of Temple's formula. The algorithm could be adapted to systems such as atoms and molecules. It is shown how to compute Green's functions from energy eigenvalues and eigenstates in the lattice theory, and relate these to physical (renormalized) coupling constants, bound state energies and Green's functions. Thus one can compute approximate physical quantities in a lattice theory that approximates a quantum field theory with specified physical coupling constants. The author discusses the errors in both approximations. In principle, the errors can be made arbitrarily small by increasing the size of the lattice, decreasing the lattice spacing and computing sufficiently long. Unfortunately, the author does not understand the infinite-volume and continuum limits well enough to quantify errors due to the lattice approximation. Thus the method is currently incomplete. The method is applied to real scalar field theories using a Fock basis of free particle states. All needed quantities can be calculated efficiently with this basis. The generalization to more complicated theories is straightforward. The author describes a computer implementation of the method and present numerical results for simple quantum mechanical systems

  16. Development of a method for personal, spatiotemporal exposure assessment.

    Science.gov (United States)

    Adams, Colby; Riggs, Philip; Volckens, John

    2009-07-01

    This work describes the development and evaluation of a high resolution, space and time-referenced sampling method for personal exposure assessment to airborne particulate matter (PM). This method integrates continuous measures of personal PM levels with the corresponding location-activity (i.e. work/school, home, transit) of the subject. Monitoring equipment include a small, portable global positioning system (GPS) receiver, a miniature aerosol nephelometer, and an ambient temperature monitor to estimate the location, time, and magnitude of personal exposure to particulate matter air pollution. Precision and accuracy of each component, as well as the integrated method performance were tested in a combination of laboratory and field tests. Spatial data was apportioned into pre-determined location-activity categories (i.e. work/school, home, transit) with a simple, temporospatially-based algorithm. The apportioning algorithm was extremely effective with an overall accuracy of 99.6%. This method allows examination of an individual's estimated exposure through space and time, which may provide new insights into exposure-activity relationships not possible with traditional exposure assessment techniques (i.e., time-integrated, filter-based measurements). Furthermore, the method is applicable to any contaminant or stressor that can be measured on an individual with a direct-reading sensor.

  17. Local Field Response Method Phenomenologically Introducing Spin Correlations

    Science.gov (United States)

    Tomaru, Tatsuya

    2018-03-01

    The local field response (LFR) method is a way of searching for the ground state in a similar manner to quantum annealing. However, the LFR method operates on a classical machine, and quantum effects are introduced through a priori information and through phenomenological means reflecting the states during the computations. The LFR method has been treated with a one-body approximation, and therefore, the effect of entanglement has not been sufficiently taken into account. In this report, spin correlations are phenomenologically introduced as one of the effects of entanglement, by which multiple tunneling at anticrossing points is taken into account. As a result, the accuracy of solutions for a 128-bit system increases by 31% compared with that without spin correlations.

  18. Assessment of chemical exposures: calculation methods for environmental professionals

    National Research Council Canada - National Science Library

    Daugherty, Jack E

    1997-01-01

    ... on by scientists, businessmen, and policymakers. Assessment of Chemical Exposures: Calculation Methods for Environmental Professionals addresses the expanding scope of exposure assessments in both the workplace and environment...

  19. Assessing Natural Isothiocyanate Air Emissions after Field Incorporation of Mustard Cover Crop

    Energy Technology Data Exchange (ETDEWEB)

    Trott, Donna M.; LePage, Jane; Hebert, Vincent

    2012-01-01

    A regional air assessment was performed to characterize volatile natural isothiocyanate (NITC) compounds in air during soil incorporation of mustard cover crops in Washington State. Field air sampling and analytical methods were developed specific to three NITCs known to be present in air at appreciable concentrations during/after field incorporation. The maximum observed concentrations in air for the allyl, benzyl, and phenethyl isothiocyanates were respectively 188, 6.1, and 0.7 lg m-3 during mustard incorporation. Based on limited inhalation toxicity information, airborne NITC concentrations did not appear to pose an acute human inhalation exposure concern to field operators and bystanders.

  20. Can mixed assessment methods make biology classes more equitable?

    Science.gov (United States)

    Cotner, Sehoya; Ballen, Cissy J

    2017-01-01

    Many factors have been proposed to explain the attrition of women in science, technology, engineering and math fields, among them the lower performance of women in introductory courses resulting from deficits in incoming preparation. We focus on the impact of mixed methods of assessment, which minimizes the impact of high-stakes exams and rewards other methods of assessment such as group participation, low-stakes quizzes and assignments, and in-class activities. We hypothesized that these mixed methods would benefit individuals who otherwise underperform on high-stakes tests. Here, we analyze gender-based performance trends in nine large (N > 1000 students) introductory biology courses in fall 2016. Females underperformed on exams compared to their male counterparts, a difference that does not exist with other methods of assessment that compose course grade. Further, we analyzed three case studies of courses that transitioned their grading schemes to either de-emphasize or emphasize exams as a proportion of total course grade. We demonstrate that the shift away from an exam emphasis consequently benefits female students, thereby closing gaps in overall performance. Further, the exam performance gap itself is reduced when the exams contribute less to overall course grade. We discuss testable predictions that follow from our hypothesis, and advocate for the use of mixed methods of assessments (possibly as part of an overall shift to active learning techniques). We conclude by challenging the student deficit model, and suggest a course deficit model as explanatory of these performance gaps, whereby the microclimate of the classroom can either raise or lower barriers to success for underrepresented groups in STEM.

  1. Can mixed assessment methods make biology classes more equitable?

    Directory of Open Access Journals (Sweden)

    Sehoya Cotner

    Full Text Available Many factors have been proposed to explain the attrition of women in science, technology, engineering and math fields, among them the lower performance of women in introductory courses resulting from deficits in incoming preparation. We focus on the impact of mixed methods of assessment, which minimizes the impact of high-stakes exams and rewards other methods of assessment such as group participation, low-stakes quizzes and assignments, and in-class activities. We hypothesized that these mixed methods would benefit individuals who otherwise underperform on high-stakes tests. Here, we analyze gender-based performance trends in nine large (N > 1000 students introductory biology courses in fall 2016. Females underperformed on exams compared to their male counterparts, a difference that does not exist with other methods of assessment that compose course grade. Further, we analyzed three case studies of courses that transitioned their grading schemes to either de-emphasize or emphasize exams as a proportion of total course grade. We demonstrate that the shift away from an exam emphasis consequently benefits female students, thereby closing gaps in overall performance. Further, the exam performance gap itself is reduced when the exams contribute less to overall course grade. We discuss testable predictions that follow from our hypothesis, and advocate for the use of mixed methods of assessments (possibly as part of an overall shift to active learning techniques. We conclude by challenging the student deficit model, and suggest a course deficit model as explanatory of these performance gaps, whereby the microclimate of the classroom can either raise or lower barriers to success for underrepresented groups in STEM.

  2. Precise magnetostatic field using the finite element method

    International Nuclear Information System (INIS)

    Nascimento, Francisco Rogerio Teixeira do

    2013-01-01

    The main objective of this work is to simulate electromagnetic fields using the Finite Element Method. Even in the easiest case of electrostatic and magnetostatic numerical simulation some problems appear when the nodal finite element is used. It is difficult to model vector fields with scalar functions mainly in non-homogeneous materials. With the aim to solve these problems two types of techniques are tried: the adaptive remeshing using nodal elements and the edge finite element that ensure the continuity of tangential components. Some numerical analysis of simple electromagnetic problems with homogeneous and non-homogeneous materials are performed using first, the adaptive remeshing based in various error indicators and second, the numerical solution of waveguides using edge finite element. (author)

  3. Magnetic field adjustment structure and method for a tapered wiggler

    Science.gov (United States)

    Halbach, Klaus

    1988-01-01

    An improved method and structure is disclosed for adjusting the magnetic field generated by a group of electromagnet poles spaced along the path of a charged particle beam to compensate for energy losses in the charged particles which comprises providing more than one winding on at least some of the electromagnet poles; connecting one respective winding on each of several consecutive adjacent electromagnet poles to a first power supply, and the other respective winding on the electromagnet pole to a different power supply in staggered order; and independently adjusting one power supply to independently vary the current in one winding on each electromagnet pole in a group whereby the magnetic field strength of each of a group of electromagnet poles may be changed in smaller increments.

  4. METHOD AND APPARATUS FOR TRAPPING IONS IN A MAGNETIC FIELD

    Science.gov (United States)

    Luce, J.S.

    1962-04-17

    A method and apparatus are described for trapping ions within an evacuated container and within a magnetic field utilizing dissociation and/or ionization of molecular ions to form atomic ions and energetic neutral particles. The atomic ions are magnetically trapped as a result of a change of charge-to- mass ratio. The molecular ions are injected into the container and into the path of an energetic carbon arc discharge which dissociates and/or ionizes a portion of the molecular ions into atomic ions and energetic neutrals. The resulting atomic ions are trapped by the magnetic field to form a circulating beam of atomic ions, and the energetic neutrals pass out of the system and may be utilized in a particle accelerator. (AEC)

  5. Remediation of deltamethrin contaminated cotton fields: residual and adsorption assessment

    Directory of Open Access Journals (Sweden)

    Rafique Uzaira

    2016-01-01

    Full Text Available Pakistan occupies a significant global position in the growing of high quality cotton. The extensive application of pesticides on agricultural products leads to environmental risk due to toxic residues in air, water and soil. This study examined the chemodynamic effect of Deltamethrin on cotton fields. Samples were collected from the cotton fields of D.G. Khan, Pakistan and analyzed for heavy metal speciation patterns. Batch experiments were administered in order to study the adsorption of Deltamethrin in cotton fields. The effect of different factors including pH, adsorbate dose, and adsorbent mass on adsorption were studied. It was observed that in general, adsorption increased with increases in the mass of adsorbate, although the trends were irregular. Residual fractions of deltamethrin in the soil and water of cotton fields were analyzed to assess concentrations of xenobiotics bound to soil particles. Results indicated that such residues are significantly higher in soil samples due to high Koc in comparison to water, indicating the former is an efficient degradation agent. Results from the batch experiment resulted in 95% removal with alkaline pH and an adsorbent-adsorbate ratio of 250:1. These results may be used to environment friendly resource management policies.

  6. Fractal analysis for assessing the level of modulation of IMRT fields

    International Nuclear Information System (INIS)

    Nauta, Marcel; Villarreal-Barajas, J. Eduardo; Tambasco, Mauro

    2011-01-01

    Purpose: To investigate the potential of three fractal dimension (FD) analysis methods (i.e., the variation, power spectrum, and variogram methods) as metrics for quantifying the degree of modulation in planned intensity modulated radiation therapy (IMRT) treatment fields, and compare the most suitable FD method to the number of monitor units (MUs), the average leaf gap, and the 2D modulation index (2D MI) for assessing modulation. Methods: The authors implemented, validated, and compared the variation, power spectrum, and variogram methods for computing the FD. Validation of the methods was done using mathematical fractional Brownian surfaces of known FD that ranged in size from 128 x 128 to 512 x 512. The authors used a test set consisting of seven head and neck carcinoma plans (50 prescribed treatment fields) to choose an FD cut-point that ensures no false positives (100% specificity) in distinguishing between moderate and high degrees of field modulation. The degree of field modulation was controlled by adjusting the fluence smoothing parameters in the Eclipse treatment planning system (Varian Medical Systems, Palo Alto, CA). The moderate modulation fields were representative of the degree of modulation used clinically at the authors' institution. The authors performed IMRT quality assurance (QA) on the 50 test fields using the MapCHECK device. The FD cut-point was applied to a validation set consisting of four head and neck plans (28 fields). The area under the curve (AUC) from receiver operating characteristic (ROC) analysis was used to compare the ability of FD, number of MUs, average leaf gap, and the 2D MI for distinguishing between the moderate and high modulation fields. Results: The authors found the variogram FD method to be the most suitable for assessing the modulation complexity of IMRT fields for head and neck carcinomas. Pass rates as measured by the gamma criterion for the MapCHECK IMRT field measurements were higher for the moderately modulated

  7. A field method for monitoring thoron-daughter working level

    International Nuclear Information System (INIS)

    Khan, A.H.; Dhandayatham, R.; Raghavayya, M.; Nambiar, P.P.V.J.

    1975-01-01

    The concept of working level, generally used for radon daughters, has been extended to the daughter products of thoron. Accordingly, thorondaughter working level (TWL) has been defined as the alpha energy released from the ultimate decay of 100 pCi/1 each of the short-lived decay products of thoron. In order to facilitate the evaluation of inhalation hazard in thorium handling areas, a simple field method has been suggested to measure the thoron-daughter working level. A comparison of the potential alpha energies from radon-daughters and that from thoron-daughter is included. (K.B.)

  8. Algebraic methods in statistical mechanics and quantum field theory

    CERN Document Server

    Emch, Dr Gérard G

    2009-01-01

    This systematic algebraic approach concerns problems involving a large number of degrees of freedom. It extends the traditional formalism of quantum mechanics, and it eliminates conceptual and mathematical difficulties common to the development of statistical mechanics and quantum field theory. Further, the approach is linked to research in applied and pure mathematics, offering a reflection of the interplay between formulation of physical motivations and self-contained descriptions of the mathematical methods.The four-part treatment begins with a survey of algebraic approaches to certain phys

  9. Ergonomic risk assessment by REBA method

    Directory of Open Access Journals (Sweden)

    A. Hassanzadeh

    2007-09-01

    Full Text Available Background and aims   Awkward posture has been recognized as one of the important risk factors of work-related musculoskeletal disorders (WMSD. The current study aimed at determining ergonomic risk level, WMSDs ratio and exploring working postures contribution to WMSD. During the study, working postures were phased and then they were scored using the REBAtool from observing the work.   Methods   To perform the study, workers of a home appliances manufacturing factory were  assessed. In order to collecting required data, each part of the body was scored and work frequency,  load/force, coupling were considered to achieve a REBA score. Nordic Questionnaire was used  to determining WMSD ratio and its relationship whit REBA score. 231 working phases were  assessed and 13761 questions using Nordic Questionnaire were answered. Percentage of the workers in press, spot welding, grinding, cutting, assembling, and painting was 15.8, 21.6, 25.9, 34.5, 89.9%, respectively. Workers were 18-54 years old and their work recording average was 52  month.   Results   REBAscore was 4-13 in under study tasks. REBA score = 9 had the most frequency  (20% and REBA score =13 had the least frequency (1.4%. Risk level in press, cutting, and  painting was high (25.5, 100, 68.2% cases. This shows that cutting has the highest risk level. On the other hand 38.5% of the workers in past 12 month had problem in different parts of their body. Totally 11.7% of the workers had problem in neck, 19.4$ in leg, 10.7% in foot, 82.5% in lower back,  87.6% in upper back and 7.8% in shoulders.10.7% of the workers had previous illness that 8.7%  of them were non occupational and 1.9% were caused their previous jobs. The REBAscore mean  and ergonomic risk level is not equal in tasks (p-value0. Action level was necessary  soon in others.   Conclusion   Risk level should be reduced specially in cutting. The heavy workload and  working height poor design, awkward

  10. Field Assessment of Energy Audit Tools for Retrofit Programs

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, J. [Univ. of Minnesota, St. Paul, MN (United States); Bohac, D. [Univ. of Minnesota, St. Paul, MN (United States); Nelson, C. [Univ. of Minnesota, St. Paul, MN (United States); Smith, I. [Univ. of Minnesota, St. Paul, MN (United States)

    2013-07-01

    This project focused on the use of home energy ratings as a tool to promote energy retrofits in existing homes. A home energy rating provides a quantitative appraisal of a home’s energy performance, usually compared to a benchmark such as the average energy use of similar homes in the same region. Rating systems based on energy performance models, the focus of this report, can establish a home’s achievable energy efficiency potential and provide a quantitative assessment of energy savings after retrofits are completed, although their accuracy needs to be verified by actual measurement or billing data. Ratings can also show homeowners where they stand compared to their neighbors, thus creating social pressure to conform to or surpass others. This project field-tested three different building performance models of varying complexity, in order to assess their value as rating systems in the context of a residential retrofit program: Home Energy Score, SIMPLE, and REM/Rate.

  11. Field method for detemining thorium-230 in soils

    International Nuclear Information System (INIS)

    Dechant, G.

    1989-05-01

    The US Department of Energy (DOE) Office of Remedial Action and Waste Technology established the Technical Measurements Center at the DOE Grand Junction, Colorado, Projects Office to develop and/or recommend measurement methods for use in support of its remedial action programs. This report describes a field method for the determination of Th-230 in soils for remedial action projects. The method involves a cold acid digestion, organic extraction, and precipitation of Th-230 for counting by alpha spectrometry. An internal Th-228 spike is added early in the method to eliminate the need to determine losses through the separation steps. A step-by-step procedure is included in the report. The method requires a small portable or mobile laboratory equipped with electrical power and ventilation. All additional equipment is commercially available and no special equipment is required. Chemical wastes for each analysis are stored for appropriate disposal off site. A chemist or chemical technician can complete 15--30 analyses per day depending primarily on the number of alpha spectrometers available. 8 refs., 2 figs., 7 tabs

  12. Determination of the maximum-depth to potential field sources by a maximum structural index method

    Science.gov (United States)

    Fedi, M.; Florio, G.

    2013-01-01

    A simple and fast determination of the limiting depth to the sources may represent a significant help to the data interpretation. To this end we explore the possibility of determining those source parameters shared by all the classes of models fitting the data. One approach is to determine the maximum depth-to-source compatible with the measured data, by using for example the well-known Bott-Smith rules. These rules involve only the knowledge of the field and its horizontal gradient maxima, and are independent from the density contrast. Thanks to the direct relationship between structural index and depth to sources we work out a simple and fast strategy to obtain the maximum depth by using the semi-automated methods, such as Euler deconvolution or depth-from-extreme-points method (DEXP). The proposed method consists in estimating the maximum depth as the one obtained for the highest allowable value of the structural index (Nmax). Nmax may be easily determined, since it depends only on the dimensionality of the problem (2D/3D) and on the nature of the analyzed field (e.g., gravity field or magnetic field). We tested our approach on synthetic models against the results obtained by the classical Bott-Smith formulas and the results are in fact very similar, confirming the validity of this method. However, while Bott-Smith formulas are restricted to the gravity field only, our method is applicable also to the magnetic field and to any derivative of the gravity and magnetic field. Our method yields a useful criterion to assess the source model based on the (∂f/∂x)max/fmax ratio. The usefulness of the method in real cases is demonstrated for a salt wall in the Mississippi basin, where the estimation of the maximum depth agrees with the seismic information.

  13. Path planning in uncertain flow fields using ensemble method

    KAUST Repository

    Wang, Tong

    2016-08-20

    An ensemble-based approach is developed to conduct optimal path planning in unsteady ocean currents under uncertainty. We focus our attention on two-dimensional steady and unsteady uncertain flows, and adopt a sampling methodology that is well suited to operational forecasts, where an ensemble of deterministic predictions is used to model and quantify uncertainty. In an operational setting, much about dynamics, topography, and forcing of the ocean environment is uncertain. To address this uncertainty, the flow field is parametrized using a finite number of independent canonical random variables with known densities, and the ensemble is generated by sampling these variables. For each of the resulting realizations of the uncertain current field, we predict the path that minimizes the travel time by solving a boundary value problem (BVP), based on the Pontryagin maximum principle. A family of backward-in-time trajectories starting at the end position is used to generate suitable initial values for the BVP solver. This allows us to examine and analyze the performance of the sampling strategy and to develop insight into extensions dealing with general circulation ocean models. In particular, the ensemble method enables us to perform a statistical analysis of travel times and consequently develop a path planning approach that accounts for these statistics. The proposed methodology is tested for a number of scenarios. We first validate our algorithms by reproducing simple canonical solutions, and then demonstrate our approach in more complex flow fields, including idealized, steady and unsteady double-gyre flows.

  14. Scattering in an intense radiation field: Time-independent methods

    International Nuclear Information System (INIS)

    Rosenberg, L.

    1977-01-01

    The standard time-independent formulation of nonrelativistic scattering theory is here extended to take into account the presence of an intense external radiation field. In the case of scattering by a static potential the extension is accomplished by the introduction of asymptotic states and intermediate-state propagators which account for the absorption and induced emission of photons by the projectile as it propagates through the field. Self-energy contributions to the propagator are included by a systematic summation of forward-scattering terms. The self-energy analysis is summarized in the form of a modified perturbation expansion of the type introduced by Watson some time ago in the context of nuclear-scattering theory. This expansion, which has a simple continued-fraction structure in the case of a single-mode field, provides a generally applicable successive approximation procedure for the propagator and the asymptotic states. The problem of scattering by a composite target is formulated using the effective-potential method. The modified perturbation expansion which accounts for self-energy effects is applicable here as well. A discussion of a coupled two-state model is included to summarize and clarify the calculational procedures

  15. Novel method for detecting weak magnetic fields at low frequencies

    Science.gov (United States)

    González-Martínez, S.; Castillo-Torres, J.; Mendoza-Santos, J. C.; Zamorano-Ulloa, R.

    2005-06-01

    A low-level-intensity magnetic field detection system has been designed and developed based on the amplification-selection process of signals. This configuration is also very sensitive to magnetic field changes produced by harmonic-like electrical currents transported in finite-length wires. Experimental and theoretical results of magnetic fields detection as low as 10-9T at 120Hz are also presented with an accuracy of around 13%. The assembled equipment is designed to measure an electromotive force induced in a free-magnetic-core coil in order to recover signals which are previously selected, despite the fact that their intensities are much lower than the environment electromagnetic radiation. The prototype has a signal-to-noise ratio of 60dB. This system also presents the advantage for using it as a portable unit of measurement. The concept and prototype may be applied, for example, as a nondestructive method to analyze any corrosion formation in metallic oil pipelines which are subjected to cathodic protection.

  16. Fields Institute International Symposium on Asymptotic Methods in Stochastics

    CERN Document Server

    Kulik, Rafal; Haye, Mohamedou; Szyszkowicz, Barbara; Zhao, Yiqiang

    2015-01-01

    This book contains articles arising from a conference in honour of mathematician-statistician Miklόs Csörgő on the occasion of his 80th birthday, held in Ottawa in July 2012. It comprises research papers and overview articles, which provide a substantial glimpse of the history and state-of-the-art of the field of asymptotic methods in probability and statistics, written by leading experts. The volume consists of twenty articles on topics on limit theorems for self-normalized processes, planar processes, the central limit theorem and laws of large numbers, change-point problems, short and long range dependent time series, applied probability and stochastic processes, and the theory and methods of statistics. It also includes Csörgő’s list of publications during more than 50 years, since 1962.

  17. Random field assessment of nanoscopic inhomogeneity of bone.

    Science.gov (United States)

    Dong, X Neil; Luo, Qing; Sparkman, Daniel M; Millwater, Harry R; Wang, Xiaodu

    2010-12-01

    Bone quality is significantly correlated with the inhomogeneous distribution of material and ultrastructural properties (e.g., modulus and mineralization) of the tissue. Current techniques for quantifying inhomogeneity consist of descriptive statistics such as mean, standard deviation and coefficient of variation. However, these parameters do not describe the spatial variations of bone properties. The objective of this study was to develop a novel statistical method to characterize and quantitatively describe the spatial variation of bone properties at ultrastructural levels. To do so, a random field defined by an exponential covariance function was used to represent the spatial uncertainty of elastic modulus by delineating the correlation of the modulus at different locations in bone lamellae. The correlation length, a characteristic parameter of the covariance function, was employed to estimate the fluctuation of the elastic modulus in the random field. Using this approach, two distribution maps of the elastic modulus within bone lamellae were generated using simulation and compared with those obtained experimentally by a combination of atomic force microscopy and nanoindentation techniques. The simulation-generated maps of elastic modulus were in close agreement with the experimental ones, thus validating the random field approach in defining the inhomogeneity of elastic modulus in lamellae of bone. Indeed, generation of such random fields will facilitate multi-scale modeling of bone in more pragmatic details. Copyright © 2010 Elsevier Inc. All rights reserved.

  18. In vivo assessment of muscle fascicle length by extended field-of-view ultrasonography

    DEFF Research Database (Denmark)

    Noorkoiv, M; Stavnsbo, A; Aagaard, Per

    2010-01-01

    The present study examined the reliability and validity of in vivo vastus lateralis (VL) fascicle length (L(f)) assessment by extended field-of-view ultrasonography (EFOV US). Intraexperimenter and intersession reliability of EFOV US were tested. Further, L(f) measured from EFOV US images were...... compared to L(f) measured from static US images (6-cm FOV) where out-of-field fascicle portions were trigonometrically estimated (linear extrapolation). Finally, spatial accuracy of the EFOV technique was assessed by comparing L(f) measured on swine VL by EFOV US to actual measurements from digital...... and by dissective assessment (digital photographs) in isolated swine VL was 0.84% ± 2.6% with an ICC of 0.99 (CI = 0.94-1.00). These results show that EFOV US is a reliable and valid method for the measurement of long muscle fascicle in vivo. Thus EFOV US analysis was proven more accurate for the assessment...

  19. Biological and chemical assessments of zinc ageing in field soils

    International Nuclear Information System (INIS)

    Donner, Erica; Broos, Kris; Heemsbergen, Diane; Warne, Michael St. J.; McLaughlin, Mike J.; Hodson, Mark E.; Nortcliff, Stephen

    2010-01-01

    As zinc (Zn) is both an essential trace element and potential toxicant, the effects of Zn fixation in soil are of practical significance. Soil samples from four field sites amended with ZnSO 4 were used to investigate ageing of soluble Zn under field conditions over a 2-year period. Lability of Zn measured using 65 Zn radioisotope dilution showed a significant decrease over time and hence evidence of Zn fixation in three of the four soils. However, 0.01 M CaCl 2 extractions and toxicity measurements using a genetically modified lux-marked bacterial biosensor did not indicate a decrease in soluble/bioavailable Zn over time. This was attributed to the strong regulatory effect of abiotic properties such as pH on these latter measurements. These results also showed that Zn ageing occurred immediately after Zn spiking, emphasising the need to incubate freshly spiked soils before ecotoxicity assessments. - Ageing effects were detected in Zn-amended field soils using 65 Zn isotopic dilution as a measure of lability, but not with either CaCl 2 extractions or a lux-marked bacterial biosensor.

  20. Domain Adaptation Methods for Improving Lab-to-field Generalization of Cocaine Detection using Wearable ECG

    Science.gov (United States)

    Natarajan, Annamalai; Angarita, Gustavo; Gaiser, Edward; Malison, Robert; Ganesan, Deepak; Marlin, Benjamin M.

    2016-01-01

    Mobile health research on illicit drug use detection typically involves a two-stage study design where data to learn detectors is first collected in lab-based trials, followed by a deployment to subjects in a free-living environment to assess detector performance. While recent work has demonstrated the feasibility of wearable sensors for illicit drug use detection in the lab setting, several key problems can limit lab-to-field generalization performance. For example, lab-based data collection often has low ecological validity, the ground-truth event labels collected in the lab may not be available at the same level of temporal granularity in the field, and there can be significant variability between subjects. In this paper, we present domain adaptation methods for assessing and mitigating potential sources of performance loss in lab-to-field generalization and apply them to the problem of cocaine use detection from wearable electrocardiogram sensor data. PMID:28090605

  1. A New Method for Coronal Magnetic Field Reconstruction

    Science.gov (United States)

    Yi, Sibaek; Choe, Gwang-Son; Cho, Kyung-Suk; Kim, Kap-Sung

    2017-08-01

    A precise way of coronal magnetic field reconstruction (extrapolation) is an indispensable tool for understanding of various solar activities. A variety of reconstruction codes have been developed so far and are available to researchers nowadays, but they more or less bear this and that shortcoming. In this paper, a new efficient method for coronal magnetic field reconstruction is presented. The method imposes only the normal components of magnetic field and current density at the bottom boundary to avoid the overspecification of the reconstruction problem, and employs vector potentials to guarantee the divergence-freeness. In our method, the normal component of current density is imposed, not by adjusting the tangential components of A, but by adjusting its normal component. This allows us to avoid a possible numerical instability that on and off arises in codes using A. In real reconstruction problems, the information for the lateral and top boundaries is absent. The arbitrariness of the boundary conditions imposed there as well as various preprocessing brings about the diversity of resulting solutions. We impose the source surface condition at the top boundary to accommodate flux imbalance, which always shows up in magnetograms. To enhance the convergence rate, we equip our code with a gradient-method type accelerator. Our code is tested on two analytical force-free solutions. When the solution is given only at the bottom boundary, our result surpasses competitors in most figures of merits devised by Schrijver et al. (2006). We have also applied our code to a real active region NOAA 11974, in which two M-class flares and a halo CME took place. The EUV observation shows a sudden appearance of an erupting loop before the first flare. Our numerical solutions show that two entwining flux tubes exist before the flare and their shackling is released after the CME with one of them opened up. We suggest that the erupting loop is created by magnetic reconnection between

  2. Field Application of the Micro Biological Survey Method for the Assessment of the Microbiological Safety of Different Water Sources in Horn of Africa and the Evaluation of the Effectiveness of Moringa Oleifera in Drinking Water Purification.

    Science.gov (United States)

    Losito, Francesca; Arienzo, Alyexandra; Somma, Daniela; Murgia, Lorenza; Stalio, Ottavia; Zuppi, Paolo; Rossi, Elisabetta; Antonini, Giovanni

    2017-06-23

    Water monitoring requires expensive instrumentations and skilled technicians. In developing Countries as Africa, the severe economic restrictions and lack of technology make water safety monitoring approaches applied in developed Countries, still not sustainable. The need to develop new methods that are suitable, affordable, and sustainable in the African context is urgent. The simple, economic and rapid Micro Biological Survey (MBS) method does not require an equipped laboratory nor special instruments and skilled technicians, but it can be very useful for routine water analysis. The aim of this work was the application of the MBS method to evaluate the microbiological safety of different water sources and the effectiveness of different drinking water treatments in the Horn of Africa. The obtained results have proved that this method could be very helpful to monitor water safety before and after various purification treatments, with the aim to control waterborne diseases especially in developing Countries, whose population is the most exposed to these diseases. In addition, it has been proved that Moringa oleifera water treatment is ineffective in decreasing bacterial load of Eritrea water samples.

  3. Application of geosites assessment method in geopark context

    Science.gov (United States)

    Martin, Simon; Perret, Amandine; Renau, Pierre; Cartier-Moulin, Olivier; Regolini-Bissig, Géraldine

    2014-05-01

    The regional natural park of the Monts d'Ardèche (Ardèche and Haute-Loire departments, France) is candidate to the European Geopark Network (EGN) in 2014. The area has a wide geodiversity - with rocks from Cambrian to Pleistocene (basalt flows) - and interesting features like phonolitic protrusions, maars and granite boulders fields. Around 115 sites were selected and documented through a geosites inventory carried out in the territory. This pre-selection was supervised by the Ardèche Geological Society and is therefore expert advice based. In the context of EGN candidature, these potential geosites were assessed with a simplified method. It follows the spirit of the method from the University of Lausanne (Reynard et al., 2007) and its recent developments: assessment of the scientific (central) value and of a set of additional values (ecological and cultural). As this assessment aimed to offer a management tool to the future geopark's authorities, a special focus was given to management aspects. In particular, the opportunities to use the site for education (from schools to universities) and for tourism as well as the existence of protection and of interpretive facilities were documented and assessed. Several interesting conclusions may be drawn from this case study: (1) expert assessment is effective when it is based on a pre-existing inventory which is well structured and documented; (2) even simplified, an assessment method is a very useful framework to expert assessment as it focuses the discussions on most important points and helps to balance the assessment; (3) whereas the inventory can be extensively detailed and partly academic, the assessment in the geopark context is objective-driven in order to answer management needs. The place of the geosites assessment among the three key players of a geopark construction process (i.e. territory's managers, local geoscientists and EGN) is also discussed. This place can be defined as the point of consensus of needs

  4. Assessment of seismic margin calculation methods

    International Nuclear Information System (INIS)

    Kennedy, R.P.; Murray, R.C.; Ravindra, M.K.; Reed, J.W.; Stevenson, J.D.

    1989-03-01

    Seismic margin review of nuclear power plants requires that the High Confidence of Low Probability of Failure (HCLPF) capacity be calculated for certain components. The candidate methods for calculating the HCLPF capacity as recommended by the Expert Panel on Quantification of Seismic Margins are the Conservative Deterministic Failure Margin (CDFM) method and the Fragility Analysis (FA) method. The present study evaluated these two methods using some representative components in order to provide further guidance in conducting seismic margin reviews. It is concluded that either of the two methods could be used for calculating HCLPF capacities. 21 refs., 9 figs., 6 tabs

  5. Travel Efficiency Assessment Method: Three Case Studies

    Science.gov (United States)

    This slide presentation summarizes three case studies EPA conducted in partnership with Boston, Kansas City, and Tucson, to assess the potential benefits of employing travel efficiency strategies in these areas.

  6. Comparison of Laboratory and Field Remote Sensing Methods to Measure Forage Quality

    OpenAIRE

    Guo, Xulin; Wilmshurst, John F.; Li, Zhaoqin

    2010-01-01

    Recent research in range ecology has emphasized the importance of forage quality as a key indicator of rangeland condition. However, we lack tools to evaluate forage quality at scales appropriate for management. Using canopy reflectance data to measure forage quality has been conducted at both laboratory and field levels separately, but little work has been conducted to evaluate these methods simultaneously. The objective of this study is to find a reliable way of assessing grassland quality ...

  7. Personnel neutron dose assessment upgrade: Volume 2, Field neutron spectrometer for health physics applications

    International Nuclear Information System (INIS)

    Brackenbush, L.W.; Reece, W.D.; Miller, S.D.

    1988-07-01

    Both the (ICRP) and the (NCPR) have recommended an increase in neutron quality factors and the adoption of effective dose equivalent methods. The series of reports entitled Personnel Neutron Dose Assessment Upgrade (PNL-6620) addresses these changes. Volume 1 in this series of reports (Personnel Neutron Dosimetry Assessment) provided guidance on the characteristics, use, and calibration of personnel neutron dosimeters in order to meet the new recommendations. This report, Volume 2: Field Neutron Spectrometer for Health Physics Applications describes the development of a portable field spectrometer which can be set up for use in a few minutes by a single person. The field spectrometer described herein represents a significant advance in improving the accuracy of neutron dose assessment. It permits an immediate analysis of the energy spectral distribution associated with the radiation from which neutron quality factor can be determined. It is now possible to depart from the use of maximum Q by determining and realistically applying a lower Q based on spectral data. The field spectrometer is made up of two modules: a detector module with built-in electronics and an analysis module with a IBM PC/reg sign/-compatible computer to control the data acquisition and analysis of data in the field. The unit is simple enough to allow the operator to perform spectral measurements with minimal training. The instrument is intended for use in steady-state radiation fields with neutrons energies covering the fission spectrum range. The prototype field spectrometer has been field tested in plutonium processing facilities, and has been proven to operate satisfactorily. The prototype field spectrometer uses a 3 He proportional counter to measure the neutron energy spectrum between 50 keV and 5 MeV and a tissue equivalent proportional counter (TEPC) to measure absorbed neutron dose

  8. Assessment of multispectral glacier mapping methods and derivation of glacier area changes, 1978–2002, in the central Southern Alps, New Zealand, from ASTER satellite data, field survey and existing inventory data

    CSIR Research Space (South Africa)

    Gjermundsen, EF

    2011-09-01

    Full Text Available patches on separate peaks (Chinn, 2001). The average summit height across the range varies from 1850 m a.s.l. in Fiordland in the south to 3000 m a.s.l. in the central Southern Alps (including the country?s highest summit, Mount Cook, at 3754 m a..., these areas were not always easy to extract with automatic methods, depending on the type of snow or ice (clean snow versus dirty ice) and steepness of the slope (snow in steeper slopes tended to be harder to extract). Most of the shaded clean snow could...

  9. Bootstrapping conformal field theories with the extremal functional method.

    Science.gov (United States)

    El-Showk, Sheer; Paulos, Miguel F

    2013-12-13

    The existence of a positive linear functional acting on the space of (differences between) conformal blocks has been shown to rule out regions in the parameter space of conformal field theories (CFTs). We argue that at the boundary of the allowed region the extremal functional contains, in principle, enough information to determine the dimensions and operator product expansion (OPE) coefficients of an infinite number of operators appearing in the correlator under analysis. Based on this idea we develop the extremal functional method (EFM), a numerical procedure for deriving the spectrum and OPE coefficients of CFTs lying on the boundary (of solution space). We test the EFM by using it to rederive the low lying spectrum and OPE coefficients of the two-dimensional Ising model based solely on the dimension of a single scalar quasiprimary--no Virasoro algebra required. Our work serves as a benchmark for applications to more interesting, less known CFTs in the near future.

  10. Application of Learning Methods to Local Electric Field Distributions in Defected Dielectric Materials

    Science.gov (United States)

    Ferris, Kim; Jones, Dumont

    2014-03-01

    Local electric fields reflect the structural and dielectric fluctuations in a semiconductor, and affect the material performance both for electron transport and carrier lifetime properties. In this paper, we use the LOCALF methodology with periodic boundary conditions to examine the local electric field distributions and its perturbations for II-VI (CdTe, Cd(1-x)Zn(x)Te) semiconductors, containing Te inclusions and small fluctuations in the local dielectric susceptibility. With inclusion of the induced-field term, the electric field distribution shows enhancements and diminishments compared to the macroscopic applied field, reflecting the microstructure characteristics of the dielectric. Learning methods are applied to these distributions to assess the spatial extent of the perturbation, and determine an electric field defined defect size as compared to its physical dimension. Critical concentrations of defects are assessed in terms of defect formation energies. This work was supported by the US Department of Homeland Security, Domestic Nuclear Detection Office, under competitively awarded contract/IAA HSHQDC-08-X-00872-e. This support does not constitute an express or implied endorsement on the part of the Gov't.

  11. Method and apparatus for measuring weak magnetic fields

    DEFF Research Database (Denmark)

    1995-01-01

    When measuring weak magnetic fields, a container containing a medium, such as a solution containing a stable radical, is placed in a polarising magnetic field, which is essentially at right angles to the field to be measured. The polarising field is interrupted rapidly, the interruption being...

  12. High throughput screening method for assessing heterogeneity of microorganisms

    NARCIS (Netherlands)

    Ingham, C.J.; Sprenkels, A.J.; van Hylckama Vlieg, J.E.T.; Bomer, Johan G.; de Vos, W.M.; van den Berg, Albert

    2006-01-01

    The invention relates to the field of microbiology. Provided is a method which is particularly powerful for High Throughput Screening (HTS) purposes. More specific a high throughput method for determining heterogeneity or interactions of microorganisms is provided.

  13. Catalyzed deuterium fueled reversed-field pinch reactor assessment

    International Nuclear Information System (INIS)

    Dobrott, D.

    1985-01-01

    This study is part of a Department of Energy supported alternate fusion fuels program at Science Applications International Corporation. The purpose of this portion of the study is to perform an assessment of a conceptual compact reversed-field pinch reactor (CRFPR) that is fueled by the catalyzed-deuterium (Cat-d) fuel cycle with respect to physics, technology, safety, and cost. The Cat-d CRFPR is compared to a d-t fueled fusion reactor with respect to several issues in this study. The comparison includes cost, reactor performance, and technology requirements for a Cat-d fueled CRFPR and a comparable cost-optimized d-t fueled conceptual design developed by LANL

  14. Mixing Methods in Assessing Coaches' Decision Making

    Science.gov (United States)

    Vergeer, Ineke; Lyle, John

    2007-01-01

    Mixing methods has recently achieved respectability as an appropriate approach to research design, offering a variety of advantages (Tashakkori & Teddlie, 2003). The purpose of this paper is to outline and evaluate a mixed methods approach within the domain of coaches' decision making. Illustrated with data from a policy-capturing study on…

  15. Radioisotope method for assessing skin blood pressure

    International Nuclear Information System (INIS)

    Tarkowska, A.; Misiunia, P.; Woytowicz, A.; Olewinski, T.

    1979-01-01

    A method of measuring the skin blood pressure (SBP) evolved by Holstein and Lassen is described. The method is based on determination of the force of pressure causing blockade of Na 131 I clearance from the site of its intradermal injection. Using this method it was found that in the lower extremities in healthy subjects the SBP approached the diastolic pressure measured by the conventional method in the brachial artery. On the other hand in patients with obliterative arteriosclerosis and in Buerger's disease the SBP was considerably lower than the diastolic arterial pressure. The authors think that the method gives a good insight into the state of blood supply to the extremities in healthy subjects and in peripheral vascular failure. (author)

  16. Testing of an accident consequence assessment model using field data

    International Nuclear Information System (INIS)

    Homma, Toshimitsu; Matsubara, Takeshi; Tomita, Kenichi

    2007-01-01

    This paper presents the results obtained from the application of an accident consequence assessment model, OSCAAR to the Iput dose reconstruction scenario of BIOMASS and also to the Chernobyl 131 I fallout scenario of EMRAS, both organized by International Atomic Energy Agency. The Iput Scenario deals with 137 Cs contamination of the catchment basin and agricultural area in the Bryansk Region of Russia, which was heavily contaminated after the Chernobyl accident. This exercise was used to test the chronic exposure pathway models in OSCAAR with actual measurements and to identify the most important sources of uncertainty with respect to each part of the assessment. The OSCAAR chronic exposure pathway models had some limitations but the refined model, COLINA almost successfully reconstructed the whole 10-year time course of 137 Cs activity concentrations in most requested types of agricultural products and natural foodstuffs. The Plavsk scenario provides a good opportunity to test not only the food chain transfer model of 131 I but also the method of assessing 131 I thyroid burden. OSCAAR showed in general good capabilities for assessing the important 131 I exposure pathways. (author)

  17. Low field orientation magnetic separation methods for magnetotactic bacteria

    International Nuclear Information System (INIS)

    Moeschler, F.D.

    1999-01-01

    Microbial biomineralisation of iron often results in a biomass that is magnetic and can be separated from water systems by the application of a magnetic field. Magnetotactic bacteria form magnetic membrane bound crystals within their structure, generally of magnetite. In nature, this enables magnetotactic bacteria to orientate themselves with respect to the local geomagnetic field. The bacteria then migrate with flagellar driven motion towards their preferred environment. This property has been harnessed to produce a process in which metal loaded magnetotactic bacteria can be recovered from a waste stream. This process is known as orientation magnetic separation. Several methods exist which permit the unique magnetic properties of individual magnetotactic bacteria to be studied, such as U-turn analysis, transmission electron microscopy and single wire cell studies. In this work an extension of U-turn analysis was developed. The bacteria were rendered non-motile by the addition of specific metal ions and the resulting 'flip time' which occurs during a field reversal enabled the magnetic moment of individual bacteria to be determined. This method proved to be much faster and more accurate than previous methods. For a successful process to be developed, large scale culturing of magnetotactic bacteria is required Experiments showed that culture vessel geometry was an important factor for high-density growth. Despite intensive studies reproducible culturing at volumes exceeding one litre was not achieved. This work showed that numerous metal ions rendered magnetotactic bacteria non-motile at concentrations below 10 ppm. Sequential adaptation raised typical levels to in excess of 100 ppm for a number of ions. such as zinc and tin. However, specific ions. such as copper or nickel, remained motility inhibiting at lower concentrations. To achieve separation using orientation magnetic separation, motile, field susceptible MTB are required. Despite successful adaptation, the

  18. Selected Tools and Methods from Quality Management Field

    Directory of Open Access Journals (Sweden)

    Kateřina BRODECKÁ

    2009-06-01

    Full Text Available Following paper describes selected tools and methods from Quality management field and their practical applications on defined examples. Solved examples were elaborated in the form of electronic support. This in detail elaborated electronic support provides students opportunity to thoroughly practice specific issues, help them to prepare for exams and consequently will lead to education improvement. Especially students of combined study form will appreciate this support. The paper specifies project objectives, subjects that will be covered by mentioned support, target groups, structure and the way of elaboration of electronic exercise book in view. The emphasis is not only on manual solution of selected examples that may help students to understand the principles and relationships, but also on solving and results interpreting of selected examples using software support. Statistic software Statgraphics Plus v 5.0 is used while working support, because it is free to use for all students of the faculty. Exemplary example from the subject Basic Statistical Methods of Quality Management is also part of this paper.

  19. [Methods and Applications of Psychological Stress State Assessment].

    Science.gov (United States)

    Li, Xin; Yang, Yadan; Hou, Yongjie; Chen, Zetao

    2015-08-01

    In this paper, the response of individual's physiological system under psychological stress state is discussed, and the theoretical support for psychological stress assessment research is provided. The two methods, i.e., the psychological stress assessment of questionnaire and physiological parameter assessment used for current psychological stress assessment are summarized. Then, the future trend of development of psychological stress assessment research is pointed out. We hope that this work could do and provide further support and help to psychological stress assessment studies.

  20. Assessing Social Isolation: Pilot Testing Different Methods.

    Science.gov (United States)

    Taylor, Harry Owen; Herbers, Stephanie; Talisman, Samuel; Morrow-Howell, Nancy

    2016-04-01

    Social isolation is a significant public health problem among many older adults; however, most of the empirical knowledge about isolation derives from community-based samples. There has been less attention given to isolation in senior housing communities. The objectives of this pilot study were to test two methods to identify socially isolated residents in low-income senior housing and compare findings about the extent of isolation from these two methods. The first method, self-report by residents, included 47 out of 135 residents who completed in-person interviews. To determine self-report isolation, residents completed the Lubben Social Network Scale 6 (LSNS-6). The second method involved a staff member who reported the extent of isolation on all 135 residents via an online survey. Results indicated that 26% of residents who were interviewed were deemed socially isolated by the LSNS-6. Staff members rated 12% of residents as having some or a lot of isolation. In comparing the two methods, staff members rated 2% of interviewed residents as having a lot of isolation. The combination of self-report and staff report could be more informative than just self-report alone, particularly when participation rates are low. However, researchers should be aware of the potential discrepancy between these two methods.

  1. Method of operator safety assessment for underground mobile mining equipment

    Science.gov (United States)

    Działak, Paulina; Karliński, Jacek; Rusiński, Eugeniusz

    2018-01-01

    The paper presents a method of assessing the safety of operators of mobile mining equipment (MME), which is adapted to current and future geological and mining conditions. The authors focused on underground mines, with special consideration of copper mines (KGHM). As extraction reaches into deeper layers of the deposit it can activate natural hazards, which, thus far, have been considered unusual and whose range and intensity are different depending on the field of operation. One of the main hazards that affect work safety and can become the main barrier in the exploitation of deposits at greater depths is climate threat. The authors have analysed the phenomena which may impact the safety of MME operators, with consideration of accidents that have not yet been studied and are not covered by the current safety standards for this group of miners. An attempt was made to develop a method for assessing the safety of MME operators, which takes into account the mentioned natural hazards and which is adapted to current and future environmental conditions in underground mines.

  2. Method of operator safety assessment for underground mobile mining equipment

    Directory of Open Access Journals (Sweden)

    Działak Paulina

    2018-01-01

    Full Text Available The paper presents a method of assessing the safety of operators of mobile mining equipment (MME, which is adapted to current and future geological and mining conditions. The authors focused on underground mines, with special consideration of copper mines (KGHM. As extraction reaches into deeper layers of the deposit it can activate natural hazards, which, thus far, have been considered unusual and whose range and intensity are different depending on the field of operation. One of the main hazards that affect work safety and can become the main barrier in the exploitation of deposits at greater depths is climate threat. The authors have analysed the phenomena which may impact the safety of MME operators, with consideration of accidents that have not yet been studied and are not covered by the current safety standards for this group of miners. An attempt was made to develop a method for assessing the safety of MME operators, which takes into account the mentioned natural hazards and which is adapted to current and future environmental conditions in underground mines.

  3. Does labelling frequency affect N rhizodeposition assessment using the cotton-wick method?

    DEFF Research Database (Denmark)

    Mahieu, S.; Fustec, J.; Jensen, Erik Steen

    2009-01-01

    The aim of the present study was to test and improve the reliability of the 15N cotton-wick method for measuring soil N derived from plant rhizodeposition, a critical value for assessing belowground nitrogen input in field-grown legumes. The effects of the concentration of the 15N labelling...... solution and the feeding frequency on assessment of nitrogen rhizodeposition were studied in two greenhouse experiments using the field pea (Pisum sativum L.). Neither the method nor the feeding frequency altered plant biomass and N partitioning, and the method appeared well adapted for assessing...... the belowground contribution of field-grown legumes to the soil N pool. However, nitrogen rhizodeposition assessment was strongly influenced by the feeding frequency and the concentration of labelling solution. At pod-filling and maturity, despite similar root 15N enrichment, the fraction of plants' belowground...

  4. Comparative field permeability measurement of permeable pavements using ASTM C1701 and NCAT permeameter methods.

    Science.gov (United States)

    Li, Hui; Kayhanian, Masoud; Harvey, John T

    2013-03-30

    Fully permeable pavement is gradually gaining support as an alternative best management practice (BMP) for stormwater runoff management. As the use of these pavements increases, a definitive test method is needed to measure hydraulic performance and to evaluate clogging, both for performance studies and for assessment of permeability for construction quality assurance and maintenance needs assessment. Two of the most commonly used permeability measurement tests for porous asphalt and pervious concrete are the National Center for Asphalt Technology (NCAT) permeameter and ASTM C1701, respectively. This study was undertaken to compare measured values for both methods in the field on a variety of permeable pavements used in current practice. The field measurements were performed using six experimental section designs with different permeable pavement surface types including pervious concrete, porous asphalt and permeable interlocking concrete pavers. Multiple measurements were performed at five locations on each pavement test section. The results showed that: (i) silicone gel is a superior sealing material to prevent water leakage compared with conventional plumbing putty; (ii) both methods (NCAT and ASTM) can effectively be used to measure the permeability of all pavement types and the surface material type will not impact the measurement precision; (iii) the permeability values measured with the ASTM method were 50-90% (75% on average) lower than those measured with the NCAT method; (iv) the larger permeameter cylinder diameter used in the ASTM method improved the reliability and reduced the variability of the measured permeability. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Evaluation of Dynamic Methods for Earthwork Assessment

    Directory of Open Access Journals (Sweden)

    Vlček Jozef

    2015-05-01

    Full Text Available Rapid development of road construction imposes requests on fast and quality methods for earthwork quality evaluation. Dynamic methods are now adopted in numerous civil engineering sections. Especially evaluation of the earthwork quality can be sped up using dynamic equipment. This paper presents the results of the parallel measurements of chosen devices for determining the level of compaction of soils. Measurements were used to develop the correlations between values obtained from various apparatuses. Correlations show that examined apparatuses are suitable for examination of compaction level of fine-grained soils with consideration of boundary conditions of used equipment. Presented methods are quick and results can be obtained immediately after measurement, and they are thus suitable in cases when construction works have to be performed in a short period of time.

  6. Blast casting requires fresh assessment of methods

    Energy Technology Data Exchange (ETDEWEB)

    Pilshaw, S.R.

    1987-08-01

    The article discusses the reasons why conventional blasting operations, mainly that of explosive products, drilling and initiation methods are inefficient, and suggests new methods and materials to overcome the problems of the conventional operations. The author suggests that the use of bulk ANFO for casting, instead of high energy and density explosives with high velocity detonation is more effective in producing heave action results. Similarly the drilling of smaller blast holes than is conventional allows better loading distribution of explosives in the rock mass. The author also suggests that casting would be more efficient if the shot rows were loaded differently to produce a variable burden blasting pattern.

  7. Comparative study of environmental impact assessment methods ...

    African Journals Online (AJOL)

    This study aims to introduce and systematically investigate the environmental issues during important decision-making stages. Meanwhile, impacts of development on the environmental components will be also analyzed. This research studies various methods of predicting the environmental changes and determining the ...

  8. Microbiological methods for assessing soil quality

    NARCIS (Netherlands)

    Bloem, J.; Hopkins, D.W.; Benedetti, A.

    2006-01-01

    This book provides a selection of microbiological methods that are already applied in regional or national soil quality monitoring programs. It is split into two parts: part one gives an overview of approaches to monitoring, evaluating and managing soil quality. Part two provides a selection of

  9. A new method for spray deposit assessment

    Science.gov (United States)

    Chester M. Himel; Leland Vaughn; Raymond P. Miskus; Arthur D. Moore

    1965-01-01

    Solid fluorescent particles suspended in a spray liquid are distributed in direct proportion to the size of the spray droplets. Use of solid fluorescent particles is the basis of a new method for visual recognition of the size and number of droplets impinging on target and nontarget portions of sprayed areas.

  10. Modelling and assessment of the electric field strength caused by mobile phone to the human head

    Directory of Open Access Journals (Sweden)

    Buckus Raimondas

    2016-01-01

    Full Text Available Background/Aim. Electromagnetic field exposure is the one of the most important physical agents that actively affects live organisms and environment. Active use of mobile phones influences the increase of electromagnetic field radiation. The aim of the study was to measure and assess the electric field strength caused by mobile phones to the human head. Methods. In this paper the software “COMSOL Multiphysics” was used to establish the electric field strength created by mobile phones around the head. Results. The second generation (2G Global System for Mobile (GSM phones that operate in the frequency band of 900 MHz and reach the power of 2 W have a stronger electric field than (2G GSM mobile phones that operate in the higher frequency band of 1,800 MHz and reach the power up to 1 W during conversation. The third generation of (3G UMTS smart phones that effectively use high (2,100 MHz radio frequency band emit the smallest electric field strength values during conversation. The highest electric field strength created by mobile phones is around the ear, i.e. the mobile phone location. The strength of mobile phone electric field on the phantom head decreases exponentially while moving sidewards from the center of the effect zone (the ear, and constitutes 1-12% of the artificial head’s surface. Conclusion. The highest electric field strength values of mobile phones are associated with their higher power, bigger specific energy absorption rate (SAR and lower frequency of mobile phone. The stronger electric field emitted by the more powerful mobile phones takes a higher percentage of the head surface. The highest electric field strength created by mobile phones is distributed over the user ear.

  11. Pulsed magnetic fields and their assessment according to the accident prevention regulation BGV B11; Gepulste magnetische Felder und Ihre Bewertung nach der Unfallverhuetungsvorschrift BGV B11

    Energy Technology Data Exchange (ETDEWEB)

    Heinrich, H. [2h-engineering, Hausen (Germany)

    2004-07-01

    The accident prevention regulation BGV B11 - Electromagnetic Fields - contains a method for the assessment of pulsed fields. This paper gives valuable hints and background information and presents a new tool for the computer-based assessment of these fields. (orig.)

  12. Method of assessing severe accident management strategies

    International Nuclear Information System (INIS)

    Kastenberg, W.E.; Apostolakis, G.; Dhir, V.K.; Okrent, D.; Jae, M.; Lim, H.; Milici, T.; Park, H.; Swider, J.; Xing, L.; Yu, D.

    1991-01-01

    Accident management can be defined as the innovative use of existing and or alternative resources, systems, and actions to prevent or mitigate a severe accident. A significant number of probabilistic safety assessments (PSAs) have been completed that yield the principal plant vulnerabilities. These vulnerabilities can be categorized as (1) dominant sequences with respect to core-melt frequency. (2) dominant sequences with respect to various risk measures. (3) dominant threats that challenge safety functions. (4) dominant threats with respect to failure of safety systems. For each sequence/threat and each combination of strategy, there may be several options available to the operator. Each strategy/option involves phenomenological and operational considerations regarding uncertainty. These considerations include uncertainties in key phenomena, operator behavior, system availability and behavior, and available information. This paper presents a methodology for assessing severe accident management strategies given the key uncertainties delineated at two workshops held at the University of California, Los Angeles. Based on decision trees and influence diagrams, the methodology is currently being applied to two case studies: cavity flooding in a pressurized water reactor (PWR) to prevent vessel penetration or failure, and drywell flooding in a boiling water reactor to prevent vessel and/or containment failure

  13. Electric field control methods for foil coils in high-voltage linear actuators

    NARCIS (Netherlands)

    Beek, van T.A.; Jansen, J.W.; Lomonova, E.A.

    2015-01-01

    This paper describes multiple electric field control methods for foil coils in high-voltage coreless linear actuators. The field control methods are evaluated using 2-D and 3-D boundary element methods. A comparison is presented between the field control methods and their ability to mitigate

  14. Quality assessment in radiological imaging methods

    International Nuclear Information System (INIS)

    Herstel, W.

    1985-01-01

    The equipment used in diagnostic radiology is becoming more and more complicated. In the imaging process four components are distinguished, each of which can introduce loss in essential information: the X-ray source, the human body, the imaging system and the observer. In nearly all imaging methods the X-ray quantum fluctuations are a limitation to observation. But there are also technical factors. As an illustration it is shown how in a television scanning process the resolution is restricted by the system parameters. A short review is given of test devices and the results are given of an image comparison based on regular bar patterns. Although this method has the disadvantage of measuring mainly the limiting resolution, the results of the test correlate reasonably well with the subjective appreciations of radiographs of bony structures made by a group of trained radiologists. Fluoroscopic systems should preferably be tested using moving structures under dynamic conditions. (author)

  15. A nomograph method for assessing body weight.

    Science.gov (United States)

    Thomas, A E; McKay, D A; Cutlip, M B

    1976-03-01

    The ratio of weight/height emerges from varied epidemiological studies as the most generally useful index of relative body mass in adults. The authors present a nomograph to facilitate use of this relationship in clinical situations. While showing the range of weight given as desirable in life insurance studies, the scale expresses relative weight as a continuous variable. This method encourages use of clinical judgment in interpreting "overweight" and "underweight" and in accounting for muscular and skeletal contributions to measured mass.

  16. Survey of Methods to Assess Workload

    Science.gov (United States)

    1979-08-01

    thesis study which had to do with the effect of binaural beats upon performan:.e (2) found out there was a subjectively experienced quality of beats ...were forced to conclude that the neuralmechanism by which binaural beats influenced performance is not open to correct subjective evaluation. In terms of...methods for developing indicies of pilot workload, FAA Report (FAA-AN-77- 15), July 1977. 2. ,’ R. E. The effect of binaural beats on performance, J

  17. [Development and application of electroanalytical methods in biomedical fields].

    Science.gov (United States)

    Kusu, Fumiyo

    2015-01-01

    To summarize our electroanalytical research in the biomedical field over the past 43 years, this review describes studies on specular reflection measurement, redox potential determination, amperometric acid sensing, HPLC with electrochemical detection, and potential oscillation across a liquid membrane. The specular reflection method was used for clarifying the adsorption of neurotransmitters and their related drugs onto a gold electrode and the interaction between dental alloys and compound iodine glycerin. A voltammetric screening test using a redox potential for the antioxidative effect of flavonoids was proposed. Amperometric acid sensing based on the measurement of the reduction prepeak current of 2-methyl-1,4-naphthoquinone (VK3) or 3,5-di-tert-buty1-1,2-benzoquinone (DBBQ) was applied to determine acid values of fats and oils, titrable acidity of coffee, and enzyme activity of lipase, free fatty acids (FFAs) in serum, short-chain fatty acids in feces, etc. The electrode reactions of phenothiazines, catechins, and cholesterol were applied to biomedical analysis using HPLC with electrochemical detection. A three-channel electrochemical detection system was utilized for the sensitive determination of redox compounds in Chinese herbal medicines. The behavior of barbituric acid derivatives was examined based on potential oscillation measurements.

  18. Electrodeless plasma acceleration system using rotating magnetic field method

    Directory of Open Access Journals (Sweden)

    T. Furukawa

    2017-11-01

    Full Text Available We have proposed Rotating Magnetic Field (RMF acceleration method as one of electrodeless plasma accelerations. In our experimental scheme, plasma generated by an rf (radio frequency antenna, is accelerated by RMF antennas, which consist of two-pair, opposed, facing coils, and these antennas are outside of a discharge tube. Therefore, there is no wear of electrodes, degrading the propulsion performance. Here, we will introduce our RMF acceleration system developed, including the experimental device, e.g., external antennas, a tapered quartz tube, a vacuum chamber, external magnets, and a pumping system. In addition, we can change RMF operation parameters (RMF applied current IRMF and RMF current phase difference ϕ, focusing on RMF current frequency fRMF by adjusting matching conditions of RMF, and investigate the dependencies on plasma parameters (electron density ne and ion velocity vi; e.g., higher increases of ne and vi (∼360 % and 55 %, respectively than previous experimental results were obtained by decreasing fRMF from 5 MHz to 0.7 MHz, whose RMF penetration condition was better according to Milroy’s expression. Moreover, time-varying component of RMF has been measured directly to survey the penetration condition experimentally.

  19. Methods to Quantify Uncertainty in Human Health Risk Assessment

    National Research Council Canada - National Science Library

    Aurelius, Lea

    1998-01-01

    ...) and other health professionals, such as the Bioenviroumental Engineer, to identify the appropriate use of probabilistic techniques for a site, and the methods by which probabilistic risk assessment...

  20. Semi-empirical equivalent field method for dose determination in midline block fields for cobalt - 60 beam

    International Nuclear Information System (INIS)

    Tagoe, S.N.A.; Nani, E.K.; Yarney, J.; Edusa, C.; Quayson-Sackey, K.; Nyamadi, K.M.; Sasu, E.

    2012-01-01

    For teletherapy treatment time calculations, midline block fields are resolved into two fields, but neglecting scattering from other fields, the effective equivalent square field size of the midline block is assumed to the resultant field. Such approach is underestimation, and may be detrimental in achieving the recommended uncertainty of ± 5 % for patient's radiation dose delivery. By comparison, the deviations of effective equivalent square field sizes by calculations and experiments were within 13.2 % for cobalt 60 beams of GWGP80 cobalt 60 teletherapy. Therefore, a modified method incorporating the scatter contributions was adopted to estimate the effective equivalent square field size for midline block field. The measured outputs of radiation beams with the block were compared with outputs of square fields without the blocks (only the block tray) at depths of 5 and 10 cm for the teletherapy machine employing isocentric technique, and the accuracy was within ± 3 % for the cobalt 60 beams. (au)

  1. Field Assessment of Energy Audit Tools for Retrofit Programs

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, J.; Bohac, D.; Nelson, C.; Smith, I.

    2013-07-01

    This project focused on the use of home energy ratings as a tool to promote energy retrofits in existing homes. A home energy rating provides a quantitative appraisal of a home's asset performance, usually compared to a benchmark such as the average energy use of similar homes in the same region. Home rating systems can help motivate homeowners in several ways. Ratings can clearly communicate a home's achievable energy efficiency potential, provide a quantitative assessment of energy savings after retrofits are completed, and show homeowners how they rate compared to their neighbors, thus creating an incentive to conform to a social standard. An important consideration is how rating tools for the retrofit market will integrate with existing home energy service programs. For residential programs that target energy savings only, home visits should be focused on key efficiency measures for that home. In order to gain wide adoption, a rating tool must be easily integrated into the field process, demonstrate consistency and reasonable accuracy to earn the trust of home energy technicians, and have a low monetary cost and time hurdle for homeowners. Along with the Home Energy Score, this project also evaluated the energy modeling performance of SIMPLE and REM/Rate.

  2. Characterisation of neutron fields: challenges in assessing the directional distribution

    International Nuclear Information System (INIS)

    Cauwels, Vanessa; Vanhavere, Filip; Reginatto, Marcel

    2014-01-01

    The SCK.CEN has carried out neutron field characterisation campaigns at several nuclear reactors. The main goal of these measurement campaigns was to evaluate the performance of different neutron personal dosemeters. To be able to evaluate the performance of neutron personal dosemeters in terms of H p (10), knowledge of the directional distribution is indispensable. This distribution was estimated by placing several personal dosemeters on all six sides of a slab phantom. The interpretation and conversion of this information into a reliable value for H p (10) requires great care. The data were analysed using three methods. In the first approach, a linear interpolation was performed on three perpendicular axes. In the other two approaches, an icosahedron was used to model the angle of incidence of the neutrons and a linear interpolation or a Bayesian analysis was performed. This study describes the limitations and advantages of each of these methods and provides recommendations for their use to estimate the personal dose equivalent H p (10) for neutron dosimetry. Neutron personal dosimetry is complicated by the fact that the neutron dose quantity H p (10) is strongly energy and angular dependent. Instead of simply assuming that the fluence is unidirectional or that the fluence is isotropic, an attempt was made to estimate the directional distribution of the neutron field using a relatively simple measurement procedure. A number of active and passive personal dosemeters were placed on the six faces of a slab phantom and the results were analysed via different algorithms to obtain partial fluences in several directions of incidence. The results from all calculations in this study show the importance of introducing information about the directional distribution of the neutron fluence for the estimation of the personal dose equivalent H p (10). The difference between H p (10) dose estimates carried out using a unidirectional or an isotropic distribution can be of up

  3. Method and apparatus for scanning a transverse field

    International Nuclear Information System (INIS)

    Stoddart, H.F.

    1978-01-01

    A transverse radionuclide scan-field imaging apparatus is described for use in scanning with particular reference to the brain. It comprises a plurality of highly focussed collimators surrounding and being focussed inwardly with respect to the scan-field and means for imparting movement to the collimators. Adjacent collimators can be stepped in radially opposite directions after each tangential scan, so that the focal point of each collimator scans at least one half of the scan-field. Each collimator is associated with a scintillator crystal and photodetector whose output is used to calculate the radioactive emission intensity at a number of points in the scan-field. (author)

  4. An information entropy model on clinical assessment of patients based on the holographic field of meridian

    Science.gov (United States)

    Wu, Jingjing; Wu, Xinming; Li, Pengfei; Li, Nan; Mao, Xiaomei; Chai, Lihe

    2017-04-01

    Meridian system is not only the basis of traditional Chinese medicine (TCM) method (e.g. acupuncture, massage), but also the core of TCM's basic theory. This paper has introduced a new informational perspective to understand the reality and the holographic field of meridian. Based on maximum information entropy principle (MIEP), a dynamic equation for the holographic field has been deduced, which reflects the evolutionary characteristics of meridian. By using self-organizing artificial neural network as algorithm, the evolutionary dynamic equation of the holographic field can be resolved to assess properties of meridians and clinically diagnose the health characteristics of patients. Finally, through some cases from clinical patients (e.g. a 30-year-old male patient, an apoplectic patient, an epilepsy patient), we use this model to assess the evolutionary properties of meridians. It is proved that this model not only has significant implications in revealing the essence of meridian in TCM, but also may play a guiding role in clinical assessment of patients based on the holographic field of meridians.

  5. Coal Field Fire Fighting - Practiced methods, strategies and tactics

    Science.gov (United States)

    Wündrich, T.; Korten, A. A.; Barth, U. H.

    2009-04-01

    achieved. For an effective and efficient fire fighting optimal tactics are requiered and can be divided into four fundamental tactics to control fire hazards: - Defense (digging away the coal, so that the coal can not begin to burn; or forming a barrier, so that the fire can not reach the not burning coal), - Rescue the coal (coal mining of a not burning seam), - Attack (active and direct cooling of burning seam), - Retreat (only monitoring till self-extinction of a burning seam). The last one is used when a fire exceeds the organizational and/or technical scope of a mission. In other words, "to control a coal fire" does not automatically and in all situations mean "to extinguish a coal fire". Best-practice tactics or a combination of them can be selected for control of a particular coal fire. For the extinguishing works different extinguishing agents are available. They can be applied by different application techniques and varying distinctive operating expenses. One application method may be the drilling of boreholes from the surface or covering the surface with low permeability soils. The mainly used extinction agents for coal field fire are as followed: Water (with or without additives), Slurry, Foaming mud/slurry, Inert gases, Dry chemicals and materials and Cryogenic agents. Because of its tremendous dimension and its complexity the worldwide challenge of coal fires is absolutely unique - it can only be solved with functional application methods, best fitting strategies and tactics, organisation and research as well as the dedication of the involved fire fighters, who work under extreme individual risks on the burning coal fields.

  6. Estimating the diffuseness of sound fields: A wavenumber analysis method

    DEFF Research Database (Denmark)

    Nolan, Melanie; Davy, John L.; Brunskog, Jonas

    2017-01-01

    The concept of a diffuse sound field is widely used in the analysis of sound in enclosures. The diffuse sound field is generally described as composed of plane waves with random phases, which wave number vectors are uniformly distributed over all angles of incidence. In this study, an interpretat...

  7. Interlaboratory Validation of the Leaching Environmental Assessment Framework (LEAF) Method 1313 and Method 1316

    Science.gov (United States)

    This document summarizes the results of an interlaboratory study conducted to generate precision estimates for two parallel batch leaching methods which are part of the Leaching Environmental Assessment Framework (LEAF). These methods are: (1) Method 1313: Liquid-Solid Partition...

  8. Assessment of soil moisture dynamics on an irrigated maize field using cosmic ray neutron sensing

    Science.gov (United States)

    Scheiffele, Lena Maria; Baroni, Gabriele; Oswald, Sascha E.

    2015-04-01

    In recent years cosmic ray neutron sensing (CRS) developed as a valuable, indirect and non-invasive method to estimate soil moisture at a scale of tens of hectares, covering the gap between point scale measurements and large scale remote sensing techniques. The method is particularly promising in cropped and irrigated fields where invasive installation of belowground measurement devices could conflict with the agricultural management. However, CRS is affected by all hydrogen pools in the measurement footprint and a fast growing biomass provides some challenges for the interpretation of the signal and application of the method for detecting soil moisture. For this aim, in this study a cosmic ray probe was installed on a field near Braunschweig (Germany) during one maize growing season (2014). The field was irrigated in stripes of 50 m width using sprinkler devices for a total of seven events. Three soil sampling campaigns were conducted throughout the growing season to assess the effect of different hydrogen pools on calibration results. Additionally, leaf area index and biomass measurements were collected to provide the relative contribution of the biomass on the CRS signal. Calibration results obtained with the different soil sampling campaigns showed some discrepancy well correlated with the biomass growth. However, after the calibration function was adjusted to account also for lattice water and soil organic carbon, thus representing an equivalent water content of the soil, the differences decreased. Soil moisture estimated with CRS responded well to precipitation and irrigation events, confirming also the effective footprint of the method (i.e., radius 300 m) and showing occurring water stress for the crop. Thus, the dynamics are in agreement with the soil moisture determined with point scale measurements but they are less affected by the heterogeneous moisture conditions within the field. For this reason, by applying a detailed calibration, CRS proves to be a

  9. MIMIC Methods for Assessing Differential Item Functioning in Polytomous Items

    Science.gov (United States)

    Wang, Wen-Chung; Shih, Ching-Lin

    2010-01-01

    Three multiple indicators-multiple causes (MIMIC) methods, namely, the standard MIMIC method (M-ST), the MIMIC method with scale purification (M-SP), and the MIMIC method with a pure anchor (M-PA), were developed to assess differential item functioning (DIF) in polytomous items. In a series of simulations, it appeared that all three methods…

  10. Alternative method for assessing coking coal plasticity

    Energy Technology Data Exchange (ETDEWEB)

    Dzuy Nguyen; Susan Woodhouse; Merrick Mahoney [University of Adelaide (Australia). BHP Billiton Newcastle Technology Centre

    2008-07-15

    Traditional plasticity measurements for coal have a number of limitations associated with the reproducibility of the tests and their use in predicting coking behaviour. This report reviews alternative rheological methods for characterising the plastic behaviour of coking coals. It reviews the application of more fundamental rheological measurements to the coal system as well as reviewing applications of rheology to other physical systems. These systems may act as potential models for the application of fundamental rheological measurements to cokemaking. The systems considered were polymer melts, coal ash melts, lava, bread making and ice cream. These systems were chosen because they exhibit some physically equivalent processes to the processes occurring during cokemaking, eg, the generation of bubbles within a softened system that then resolidifies. A number of recommendations were made; the steady and oscillatory shear squeeze flow techniques be further investigated to determine if the measured rheology characteristics are related to transformations within the coke oven and the characteristics of resultant coke; modification of Gieseler plastometers for more fundamental rheology measurements not be attempted.

  11. Risk assessment methods for life cycle costing in buildings

    Directory of Open Access Journals (Sweden)

    Oduyemi Olufolahan

    2016-01-01

    Originality/value. This paper contributes with new outlooks aimed at assessing the current level of awareness, usage and advocated benefits of risk assessment methods in LCC and adds to the limited empirical studies on risk assessment to corporate occupants and decision makers.

  12. CAPABILITY ASSESSMENT OF MEASURING EQUIPMENT USING STATISTIC METHOD

    Directory of Open Access Journals (Sweden)

    Pavel POLÁK

    2014-10-01

    Full Text Available Capability assessment of the measurement device is one of the methods of process quality control. Only in case the measurement device is capable, the capability of the measurement and consequently production process can be assessed. This paper deals with assessment of the capability of the measuring device using indices Cg and Cgk.

  13. Assessing Commercial and Alternative Poultry Processing Methods using Microbiome Analyses

    Science.gov (United States)

    Assessing poultry processing methods/strategies has historically used culture-based methods to assess bacterial changes or reductions, both in terms of general microbial communities (e.g. total aerobic bacteria) or zoonotic pathogens of interest (e.g. Salmonella, Campylobacter). The advent of next ...

  14. Qualitative Assessment of Inquiry-Based Teaching Methods

    Science.gov (United States)

    Briggs, Michael; Long, George; Owens, Katrina

    2011-01-01

    A new approach to teaching method assessment using student focused qualitative studies and the theoretical framework of mental models is proposed. The methodology is considered specifically for the advantages it offers when applied to the assessment of inquiry-based teaching methods. The theoretical foundation of mental models is discussed, and…

  15. ALTERNATIVE FIELD METHODS TO TREAT MERCURY IN SOIL

    Energy Technology Data Exchange (ETDEWEB)

    Ernest F. Stine Jr; Steven T. Downey

    2002-08-14

    U.S. Department of Energy (DOE) used large quantities of mercury in the uranium separating process from the 1950s until the late 1980s in support of national defense. Some of this mercury, as well as other hazardous metals and radionuclides, found its way into, and under, several buildings, soil and subsurface soils and into some of the surface waters. Several of these areas may pose potential health or environmental risks and must be dealt with under current environmental regulations. DOE's National Energy Technology Laboratory (NETL) awarded a contract ''Alternative Field Methods to Treat Mercury in Soil'' to IT Group, Knoxville TN (IT) and its subcontractor NFS, Erwin, TN to identify remedial methods to clean up mercury-contaminated high-clay content soils using proven treatment chemistries. The sites of interest were the Y-12 National Security Complex located in Oak Ridge, Tennessee, the David Witherspoon properties located in Knoxville, Tennessee, and at other similarly contaminated sites. The primary laboratory-scale contract objectives were (1) to safely retrieve and test samples of contaminated soil in an approved laboratory and (2) to determine an acceptable treatment method to ensure that the mercury does not leach from the soil above regulatory levels. The leaching requirements were to meet the TC (0.2 mg/l) and UTS (0.025 mg/l) TCLP criteria. In-situ treatments were preferred to control potential mercury vapors emissions and liquid mercury spills associated with ex-situ treatments. All laboratory work was conducted in IT's and NFS laboratories. Mercury contaminated nonradioactive soil from under the Alpha 2 building in the Y-12 complex was used. This soils contained insufficient levels of leachable mercury and resulted in TCLP mercury concentrations that were similar to the applicable LDR limits. The soil was spiked at multiple levels with metallic (up to 6000 mg/l) and soluble mercury compounds (up to 500 mg/kg) to

  16. Assessing Precision in Conventional Field Measurements of Individual Tree Attributes

    Directory of Open Access Journals (Sweden)

    Ville Luoma

    2017-02-01

    Full Text Available Forest resource information has a hierarchical structure: individual tree attributes are summed at the plot level and then in turn, plot-level estimates are used to derive stand or large-area estimates of forest resources. Due to this hierarchy, it is imperative that individual tree attributes are measured with accuracy and precision. With the widespread use of different measurement tools, it is also important to understand the expected degree of precision associated with these measurements. The most prevalent tree attributes measured in the field are tree species, stem diameter-at-breast-height (dbh, and tree height. For dbh and height, the most commonly used measuring devices are calipers and clinometers, respectively. The aim of our study was to characterize the precision of individual tree dbh and height measurements in boreal forest conditions when using calipers and clinometers. The data consisted of 319 sample trees at a study area in Evo, southern Finland. The sample trees were measured independently by four trained mensurationists. The standard deviation in tree dbh and height measurements was 0.3 cm (1.5% and 0.5 m (2.9%, respectively. Precision was also assessed by tree species and tree size classes; however, there were no statistically significant differences between the mensurationists for dbh or height measurements. Our study offers insights into the expected precision of tree dbh and height as measured with the most commonly used devices. These results are important when using sample plot data in forest inventory applications, especially now, at a time when new tree attribute measurement techniques based on remote sensing are being developed and compared to the conventional caliper and clinometer measurements.

  17. Suggestions on the Development of Safety Culture Assessment Method

    International Nuclear Information System (INIS)

    Choi, Young Sung; Choi, Kwang Sik; Kim, Woong Sik

    2006-01-01

    Several efforts have been made to assess safety culture of organization that operates nuclear power plants in Korea. The MOST and KINS played a major role to develop assessment methods and KHNP applied them to its NPPs. This paper explains the two methods developed by KINS briefly and presents the insights obtained from the two different applications. It concludes with some suggestions for safety culture assessment based on the insights

  18. The assessment of electromagnetic field radiation exposure for mobile phone users

    Directory of Open Access Journals (Sweden)

    Buckus Raimondas

    2014-01-01

    Full Text Available Background/Aim. During recent years, the widespread use of mobile phones has resulted in increased human exposure to electromagnetic field radiation and to health risks. Increased usage of mobile phones at the close proximity raises questions and doubts in safety of mobile phone users. The aim of the study was to assess an electromagnetic field radiation exposure for mobile phone users by measuring electromagnetic field strength in different settings at the distance of 1 to 30 cm from the mobile user. Methods. In this paper, the measurements of electric field strength exposure were conducted on different brand of mobile phones by the call-related factors: urban/rural area, indoor/outdoor setting and moving/stationary mode during calls. The different types of mobile phone were placed facing the field probe at 1 cm, 10 cm, 20 cm and 30 cm distance. Results. The highest electric field strength was recorded for calls made in rural area (indoors while the lowest electric field strength was recorded for calls made in urban area (outdoors. Calls made from a phone in a moving car gave a similar result like for indoor calls; however, calls made from a phone in a moving car exposed electric field strength two times more than that of calls in a standing (motionless position. Conclusion. Electromagnetic field radiation depends on mobile phone power class and factors, like urban or rural area, outdoor or indoor, moving or motionless position, and the distance of the mobile phone from the phone user. It is recommended to keep a mobile phone in the safe distance of 10, 20 or 30 cm from the body (especially head during the calls.

  19. Assessment methods in surgical training in the United Kingdom

    Directory of Open Access Journals (Sweden)

    Evgenios Evgeniou

    2013-02-01

    Full Text Available A career in surgery in the United Kingdom demands a commitment to a long journey of assessment. The assessment methods used must ensure that the appropriate candidates are selected into a programme of study or a job and must guarantee public safety by regulating the progression of surgical trainees and the certification of trained surgeons. This review attempts to analyse the psychometric properties of various assessment methods used in the selection of candidates to medical school, job selection, progression in training, and certification. Validity is an indicator of how well an assessment measures what it is designed to measure. Reliability informs us whether a test is consistent in its outcome by measuring the reproducibility and discriminating ability of the test. In the long journey of assessment in surgical training, the same assessment formats are frequently being used for selection into a programme of study, job selection, progression, and certification. Although similar assessment methods are being used for different purposes in surgical training, the psychometric properties of these assessment methods have not been examined separately for each purpose. Because of the significance of these assessments for trainees and patients, their reliability and validity should be examined thoroughly in every context where the assessment method is being used.

  20. Hazard surveillance for workplace magnetic fields. 1: Walkaround sampling method for measuring ambient field magnitude; 2: Field characteristics from waveform measurements

    Energy Technology Data Exchange (ETDEWEB)

    Methner, M.M.; Bowman, J.D.

    1998-03-01

    Recent epidemiologic research has suggested that exposure to extremely low frequency (ELF) magnetic fields (MF) may be associated with leukemia, brain cancer, spontaneous abortions, and Alzheimer`s disease. A walkaround sampling method for measuring ambient ELF-MF levels was developed for use in conducting occupational hazard surveillance. This survey was designed to determine the range of MF levels at different industrial facilities so they could be categorized by MF levels and identified for possible subsequent personal exposure assessments. Industries were selected based on their annual electric power consumption in accordance with the hypothesis that large power consumers would have higher ambient MFs when compared with lower power consumers. Sixty-two facilities within thirteen 2-digit Standard Industrial Classifications (SIC) were selected based on their willingness to participate. A traditional industrial hygiene walkaround survey was conducted to identify MF sources, with a special emphasis on work stations.

  1. Inventory of LCIA selection methods for assessing toxic releases. Methods and typology report part B

    DEFF Research Database (Denmark)

    Larsen, Henrik Fred; Birkved, Morten; Hauschild, Michael Zwicky

    method(s) in Work package 8 (WP8) of the OMNIITOX project. The selection methods and the other CRS methods are described in detail, a set of evaluation criteria are developed and the methods are evaluated against these criteria. This report (Deliverable 11B (D11B)) gives the results from task 7.1d, 7.1e......This report describes an inventory of Life Cycle Impact Assessment (LCIA) selection methods for assessing toxic releases. It consists of an inventory of current selection methods and other Chemical Ranking and Scoring (CRS) methods assessed to be relevant for the development of (a) new selection...... and 7.1f of WP 7 for selection methods. The other part of D11 (D11A) is reported in another report and deals with characterisation methods. A selection method is a method for prioritising chemical emissions to be included in an LCIA characterisation of toxic releases, i.e. calculating indicator scores...

  2. Volume of visual field assessed with kinetic perimetry and its application to static perimetry

    Directory of Open Access Journals (Sweden)

    Christoforidis JB

    2011-04-01

    Full Text Available John B ChristoforidisCollege of Medicine, The Ohio State University, Columbus, OH, USABackground: The purpose of this study was to quantify the volume of the kinetic visual field with a single unit that accounts for visual field area and differential luminance sensitivity.Methods: Kinetic visual field perimetry was performed with a Goldmann perimeter using I4e, I3e, I2e, and I1e targets. The visual fields of 25 normal volunteers (17 women, eight men of mean age 33.9 ± 10.1 (range 17–64 years were obtained and digitized. Isopter areas were measured with a method devised to correct cartographic distortion due to polar projection inherent in perimetry and are expressed in steradians. The third dimension of each isopter represents sensitivity to target luminance and was calculated as log (target luminance-1. If luminance is expressed in cd/m2, the values for the third dimension are 0.5 for I4e, 1.0 for I3e, 1.5 for I2e, and 2.0 for I1e. The resulting unit is a steradian (log 103 (cd/m2-1 which is referred to as a Goldmann. In addition, the visual fields of four patients with representative visual defect patterns were examined and compared with normal subjects.Results: Mean isopter areas for normal subjects were 3.092 ± 0.242 steradians for I4e, 2.349 ± 0.280 steradians for I3e, 1.242 ± 0.263 steradians for I2e, and 0.251 ± 0.114 steradians for the I1e target. Isopter volumes were 1.546 ± 0.121 Goldmanns for the I4e target, 1.174 ± 0.140 Goldmanns for I3e, 0.621 ± 0.131 Goldmanns for I2e, and 0.126 ± 0.057 Goldmanns for I1e. The total mean visual field volume in our study for the I target was 3.467 ± 0.371 Goldmanns.Conclusion: The volume of the island of vision may be used to quantify a visual field with a single value which contains information about both visual field extension and differential luminance sensitivity. This technique may be used to assess the progression or stability of visual field defects over time. A similar method may

  3. Capability Assessment of the Equilibrium Field System in KTX

    International Nuclear Information System (INIS)

    Luo Bing; You Wei; Tan Mingsheng; Bai Wei; Mao Wenzhe; Li Hong; Liu Adi; Lan Tao; Xie Jinlin; Liu Wandong; Luo Zhengping; Xiao Bingjia; Guo Yong

    2016-01-01

    Radial equilibrium of the KTX plasma column is maintained by the vertical field which is produced by the equilibrium field coils. The equilibrium is also affected by the eddy current, which is generated by the coupling of copper shell, plasma and poloidal field coils. An equivalent circuit model is developed to analyze the dynamic performance of equilibrium field coils, without auxiliary power input to equilibrium field coils and passive conductors. Considering the coupling of poloidal field coils, copper shell and plasma, the evolution of spatial distribution of the eddy current density on the copper shell is estimated by finite element to analyze the effect of shell to balance. The simulation results show that the copper shell and equilibrium field coils can provide enough vertical field to balance 1 MA plasma current in phase 1 of a KTX discharge. Auxiliary power supply on the EQ coils is necessary to control the horizontal displacement of KTX due to the finite resistance effect of the shell. (paper)

  4. Field calculations. Part I: Choice of variables and methods

    International Nuclear Information System (INIS)

    Turner, L.R.

    1981-01-01

    Magnetostatic calculations can involve (in order of increasing complexity) conductors only, material with constant or infinite permeability, or material with variable permeability. We consider here only the most general case, calculations involving ferritic material with variable permeability. Variables suitable for magnetostatic calculations are the magnetic field, the magnetic vector potential, and the magnetic scalar potential. For two-dimensional calculations the potentials, which each have only one component, have advantages over the field, which has two components. Because it is a single-valued variable, the vector potential is perhaps the best variable for two-dimensional calculations. In three dimensions, both the field and the vector potential have three components; the scalar potential, with only one component,provides a much smaller system of equations to be solved. However the scalar potential is not single-valued. To circumvent this problem, a calculation with two scalar potentials can be performed. The scalar potential whose source is the conductors can be calculated directly by the Biot-Savart law, and the scalar potential whose source is the magnetized material is single valued. However in some situations, the fields from the two potentials nearly cancel; and the numerical accuracy is lost. The 3-D magnetostatic program TOSCA employs a single total scalar potential; the program GFUN uses the magnetic field as its variable

  5. A novel approach to assess the treatment response using Gaussian random field in PET

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Mengdie [Department of Biomedical Engineering, Tsinghua University, Beijing 100084, China and Center for Advanced Medical Imaging Science, Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States); Guo, Ning [Center for Advanced Medical Imaging Science, Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States); Hu, Guangshu; Zhang, Hui, E-mail: hzhang@mail.tsinghua.edu.cn, E-mail: li.quanzheng@mgh.harvard.edu [Department of Biomedical Engineering, Tsinghua University, Beijing 100084 (China); El Fakhri, Georges; Li, Quanzheng, E-mail: hzhang@mail.tsinghua.edu.cn, E-mail: li.quanzheng@mgh.harvard.edu [Center for Advanced Medical Imaging Science, Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, Massachusetts 02114 and Department of Radiology, Harvard Medical School, Boston, Massachusetts 02115 (United States)

    2016-02-15

    Purpose: The assessment of early therapeutic response to anticancer therapy is vital for treatment planning and patient management in clinic. With the development of personal treatment plan, the early treatment response, especially before any anatomically apparent changes after treatment, becomes urgent need in clinic. Positron emission tomography (PET) imaging serves an important role in clinical oncology for tumor detection, staging, and therapy response assessment. Many studies on therapy response involve interpretation of differences between two PET images, usually in terms of standardized uptake values (SUVs). However, the quantitative accuracy of this measurement is limited. This work proposes a statistically robust approach for therapy response assessment based on Gaussian random field (GRF) to provide a statistically more meaningful scale to evaluate therapy effects. Methods: The authors propose a new criterion for therapeutic assessment by incorporating image noise into traditional SUV method. An analytical method based on the approximate expressions of the Fisher information matrix was applied to model the variance of individual pixels in reconstructed images. A zero mean unit variance GRF under the null hypothesis (no response to therapy) was obtained by normalizing each pixel of the post-therapy image with the mean and standard deviation of the pretherapy image. The performance of the proposed method was evaluated by Monte Carlo simulation, where XCAT phantoms (128{sup 2} pixels) with lesions of various diameters (2–6 mm), multiple tumor-to-background contrasts (3–10), and different changes in intensity (6.25%–30%) were used. The receiver operating characteristic curves and the corresponding areas under the curve were computed for both the proposed method and the traditional methods whose figure of merit is the percentage change of SUVs. The formula for the false positive rate (FPR) estimation was developed for the proposed therapy response

  6. DO TIE LABORATORY BASED METHODS REALLY REFLECT FIELD CONDITIONS

    Science.gov (United States)

    Sediment Toxicity Identification and Evaluation (TIE) methods have been developed for both interstitial waters and whole sediments. These relatively simple laboratory methods are designed to identify specific toxicants or classes of toxicants in sediments; however, the question ...

  7. Neutron optics using transverse field neutron spin echo method

    International Nuclear Information System (INIS)

    Achiwa, Norio; Hino, Masahiro; Yamauchi, Yoshihiro; Takakura, Hiroyuki; Tasaki, Seiji; Akiyoshi, Tsunekazu; Ebisawa, Toru.

    1993-01-01

    A neutron spin echo (NSE) spectrometer with perpendicular magnetic field to the neutron scattering plane, using an iron yoke type electro-magnet has been developed. A combination of cold neutron guider, supermirror neutron polarizer of double reflection type and supermirror neutron analyser was adopted for the spectrometer. The first application of the NSE spectrometer to neutron optics by passing Larmor precessing neutrons through gas, solid and liquid materials of several different lengths which are inserted in one of the precession field have been examined. Preliminary NSE spectra of this sample geometry are discussed. (author)

  8. Assessment of hip dysplasia and osteoarthritis: Variability of different methods

    International Nuclear Information System (INIS)

    Troelsen, Anders; Elmengaard, Brian; Soeballe, Kjeld; Roemer, Lone; Kring, Soeren

    2010-01-01

    Background: Reliable assessment of hip dysplasia and osteoarthritis is crucial in young adults who may benefit from joint-preserving surgery. Purpose: To investigate the variability of different methods for diagnostic assessment of hip dysplasia and osteoarthritis. Material and Methods: By each of four observers, two assessments were done by vision and two by angle construction. For both methods, the intra- and interobserver variability of center-edge and acetabular index angle assessment were analyzed. The observers' ability to diagnose hip dysplasia and osteoarthritis were assessed. All measures were compared to those made on computed tomography scan. Results: Intra- and interobserver variability of angle assessment was less when angles were drawn compared with assessment by vision, and the observers' ability to diagnose hip dysplasia improved when angles were drawn. Assessment of osteoarthritis in general showed poor agreement with findings on computed tomography scan. Conclusion: We recommend that angles always should be drawn for assessment of hip dysplasia on pelvic radiographs. Given the inherent variability of diagnostic assessment of hip dysplasia, a computed tomography scan could be considered in patients with relevant hip symptoms and a center-edge angle between 20 deg and 30 deg. Osteoarthritis should be assessed by measuring the joint space width or by classifying the Toennis grade as either 0-1 or 2-3

  9. Assessment of hip dysplasia and osteoarthritis: Variability of different methods

    Energy Technology Data Exchange (ETDEWEB)

    Troelsen, Anders; Elmengaard, Brian; Soeballe, Kjeld (Orthopedic Research Unit, Univ. Hospital of Aarhus, Aarhus (Denmark)), e-mail: a_troelsen@hotmail.com; Roemer, Lone (Dept. of Radiology, Univ. Hospital of Aarhus, Aarhus (Denmark)); Kring, Soeren (Dept. of Orthopedic Surgery, Aabenraa Hospital, Aabenraa (Denmark))

    2010-03-15

    Background: Reliable assessment of hip dysplasia and osteoarthritis is crucial in young adults who may benefit from joint-preserving surgery. Purpose: To investigate the variability of different methods for diagnostic assessment of hip dysplasia and osteoarthritis. Material and Methods: By each of four observers, two assessments were done by vision and two by angle construction. For both methods, the intra- and interobserver variability of center-edge and acetabular index angle assessment were analyzed. The observers' ability to diagnose hip dysplasia and osteoarthritis were assessed. All measures were compared to those made on computed tomography scan. Results: Intra- and interobserver variability of angle assessment was less when angles were drawn compared with assessment by vision, and the observers' ability to diagnose hip dysplasia improved when angles were drawn. Assessment of osteoarthritis in general showed poor agreement with findings on computed tomography scan. Conclusion: We recommend that angles always should be drawn for assessment of hip dysplasia on pelvic radiographs. Given the inherent variability of diagnostic assessment of hip dysplasia, a computed tomography scan could be considered in patients with relevant hip symptoms and a center-edge angle between 20 deg and 30 deg. Osteoarthritis should be assessed by measuring the joint space width or by classifying the Toennis grade as either 0-1 or 2-3

  10. Inverse transformation algorithm of transient electromagnetic field and its high-resolution continuous imaging interpretation method

    International Nuclear Information System (INIS)

    Qi, Zhipeng; Li, Xiu; Lu, Xushan; Zhang, Yingying; Yao, Weihua

    2015-01-01

    We introduce a new and potentially useful method for wave field inverse transformation and its application in transient electromagnetic method (TEM) 3D interpretation. The diffusive EM field is known to have a unique integral representation in terms of a fictitious wave field that satisfies a wave equation. The continuous imaging of TEM can be accomplished using the imaging methods in seismic interpretation after the diffusion equation is transformed into a fictitious wave equation. The interpretation method based on the imaging of a fictitious wave field could be used as a fast 3D inversion method. Moreover, the fictitious wave field possesses some wave field features making it possible for the application of a wave field interpretation method in TEM to improve the prospecting resolution.Wave field transformation is a key issue in the migration imaging of a fictitious wave field. The equation in the wave field transformation belongs to the first class Fredholm integration equation, which is a typical ill-posed equation. Additionally, TEM has a large dynamic time range, which also facilitates the weakness of this ill-posed problem. The wave field transformation is implemented by using pre-conditioned regularized conjugate gradient method. The continuous imaging of a fictitious wave field is implemented by using Kirchhoff integration. A synthetic aperture and deconvolution algorithm is also introduced to improve the interpretation resolution. We interpreted field data by the method proposed in this paper, and obtained a satisfying interpretation result. (paper)

  11. Assessment of Agricultural Water Productivity for Tea Production in Tea Fields of Guilan Province

    Directory of Open Access Journals (Sweden)

    kourosh majdsalimi

    2016-05-01

    Full Text Available Water productivity index is one of the main factors in efficient use of water for agricultural products. In this study, the rate of water productivity (WP in six irrigated tea fields and three rainfed (no irrigation were assessed by farmer’s management for two years (2009-2010. Yield of each tea field in successive harvests, soil moisture monitoring by gravimetric soil and use of water balance equation was conducted during the growing seasons. Volume of water entered to irrigation system and amount of water reached to surface level were also measured. Tea mean yield in irrigated and rainfed field were 2843 and 1095 Kg. ha-1, respectively. Average of gross irrigation and effective rainfall (WP and irrigation water productivity (IWP in the irrigated fields were 4.39 and 4.55 kg (made tea ha-1 mm-1 and average of net WP (actual evaportanspiration and net IWP was 5.18 and 6.61 kg ha-1 mm-1, respectively. Average WP in rainfed tea fields was 3.4 kg ha-1 for each mm of effective rainfall. The most effective factors on WP reduction in tea fields were improper harvesting operations (un standard plucking and economic problems. Moreover, improper operation and maintenance and old irrigation systems and unprincipled irrigation scheduling in irrigated tea fields were also effective on WP reduction. Comparing the results of this study with other studies in past, showed that by implementing the proper methods in irrigation management and appropriate agricultural practices can improve water productivity in tea fields.

  12. Methods of Comprehensive Assessment for China’s Energy Sustainability

    Science.gov (United States)

    Xu, Zhijin; Song, Yankui

    2018-02-01

    In order to assess the sustainable development of China’s energy objectively and accurately, we need to establish a reasonable indicator system for energy sustainability and make a targeted comprehensive assessment with the scientific methods. This paper constructs a comprehensive indicator system for energy sustainability from five aspects of economy, society, environment, energy resources and energy technology based on the theory of sustainable development and the theory of symbiosis. On this basis, it establishes and discusses the assessment models and the general assessment methods for energy sustainability with the help of fuzzy mathematics. It is of some reference for promoting the sustainable development of China’s energy, economy and society.

  13. Non-destructive assessment of grapevine water status in the field using a portable NIR spectrophotometer.

    Science.gov (United States)

    Tardaguila, Javier; Fernández-Novales, Juan; Gutiérrez, Salvador; Diago, Maria Paz

    2017-08-01

    Until now, the majority of methods employed to assess grapevine water status have been destructive, time-intensive, costly and provide information of a limited number of samples, thus the ability of revealing within-field water status variability is reduced. The goal of this work was to evaluate the capability of non-invasive, portable near infrared (NIR) spectroscopy acquired in the field, to assess the grapevine water status in diverse varieties, grown under different environmental conditions, in a fast and reliable way. The research was conducted 2 weeks before harvest in 2012, in two commercial vineyards, planted with eight different varieties. Spectral measurements were acquired in the field on the adaxial and abaxial sides of 160 individual leaves (20 leaves per variety) using a commercially available handheld spectrophotometer (1600-2400 nm). Principal component analysis (PCA) and modified partial least squares (MPLS) were used to interpret the spectra and to develop reliable prediction models for stem water potential (Ψ s ) (cross-validation correlation coefficient (r cv ) ranged from 0.77 to 0.93, and standard error of cross validation (SECV) ranged from 0.10 to 0.23), and leaf relative water content (RWC) (r cv ranged from 0.66 to 0.81, and SECV between 1.93 and 3.20). The performance differences between models built from abaxial and adaxial-acquired spectra is also discussed. The capability of non-invasive NIR spectroscopy to reliably assess the grapevine water status under field conditions was proved. This technique can be a suitable and promising tool to appraise within-field variability of plant water status, helpful to define optimised irrigation strategies in the wine industry. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  14. Revisiting Individual Creativity Assessment: Triangulation in Subjective and Objective Assessment Methods

    Science.gov (United States)

    Park, Namgyoo K.; Chun, Monica Youngshin; Lee, Jinju

    2016-01-01

    Compared to the significant development of creativity studies, individual creativity research has not reached a meaningful consensus regarding the most valid and reliable method for assessing individual creativity. This study revisited 2 of the most popular methods for assessing individual creativity: subjective and objective methods. This study…

  15. Cross-comparison and evaluation of air pollution field estimation methods

    Science.gov (United States)

    Yu, Haofei; Russell, Armistead; Mulholland, James; Odman, Talat; Hu, Yongtao; Chang, Howard H.; Kumar, Naresh

    2018-04-01

    Accurate estimates of human exposure is critical for air pollution health studies and a variety of methods are currently being used to assign pollutant concentrations to populations. Results from these methods may differ substantially, which can affect the outcomes of health impact assessments. Here, we applied 14 methods for developing spatiotemporal air pollutant concentration fields of eight pollutants to the Atlanta, Georgia region. These methods include eight methods relying mostly on air quality observations (CM: central monitor; SA: spatial average; IDW: inverse distance weighting; KRIG: kriging; TESS-D: discontinuous tessellation; TESS-NN: natural neighbor tessellation with interpolation; LUR: land use regression; AOD: downscaled satellite-derived aerosol optical depth), one using the RLINE dispersion model, and five methods using a chemical transport model (CMAQ), with and without using observational data to constrain results. The derived fields were evaluated and compared. Overall, all methods generally perform better at urban than rural area, and for secondary than primary pollutants. We found the CM and SA methods may be appropriate only for small domains, and for secondary pollutants, though the SA method lead to large negative spatial correlations when using data withholding for PM2.5 (spatial correlation coefficient R = -0.81). The TESS-D method was found to have major limitations. Results of the IDW, KRIG and TESS-NN methods are similar. They are found to be better suited for secondary pollutants because of their satisfactory temporal performance (e.g. average temporal R2 > 0.85 for PM2.5 but less than 0.35 for primary pollutant NO2). In addition, they are suitable for areas with relatively dense monitoring networks due to their inability to capture spatial concentration variabilities, as indicated by the negative spatial R (lower than -0.2 for PM2.5 when assessed using data withholding). The performance of LUR and AOD methods were similar to

  16. Assessment of medical communication skills by computer: assessment method and student experiences

    NARCIS (Netherlands)

    Hulsman, R. L.; Mollema, E. D.; Hoos, A. M.; de Haes, J. C. J. M.; Donnison-Speijer, J. D.

    2004-01-01

    BACKGROUND A computer-assisted assessment (CAA) program for communication skills designated ACT was developed using the objective structured video examination (OSVE) format. This method features assessment of cognitive scripts underlying communication behaviour, a broad range of communication

  17. Computational methods in several fields of radiation dosimetry

    International Nuclear Information System (INIS)

    Paretzke, Herwig G.

    2010-01-01

    Full text: Radiation dosimetry has to cope with a wide spectrum of applications and requirements in time and size. The ubiquitous presence of various radiation fields or radionuclides in the human home, working, urban or agricultural environment can lead to various dosimetric tasks starting from radioecology, retrospective and predictive dosimetry, personal dosimetry, up to measurements of radionuclide concentrations in environmental and food product and, finally in persons and their excreta. In all these fields measurements and computational models for the interpretation or understanding of observations are employed explicitly or implicitly. In this lecture some examples of own computational models will be given from the various dosimetric fields, including a) Radioecology (e.g. with the code systems based on ECOSYS, which was developed far before the Chernobyl reactor accident, and tested thoroughly afterwards), b) Internal dosimetry (improved metabolism models based on our own data), c) External dosimetry (with the new ICRU-ICRP-Voxelphantom developed by our lab), d) Radiation therapy (with GEANT IV as applied to mixed reactor radiation incident on individualized voxel phantoms), e) Some aspects of nanodosimetric track structure computations (not dealt with in the other presentation of this author). Finally, some general remarks will be made on the high explicit or implicit importance of computational models in radiation protection and other research field dealing with large systems, as well as on good scientific practices which should generally be followed when developing and applying such computational models

  18. Effective and efficient method of calculating Bessel beam fields

    CSIR Research Space (South Africa)

    Litvin, IA

    2005-01-01

    Full Text Available Bessel beams have gathered much interest of late due to their properties of near diffraction free propagation and self reconstruction after obstacles. Such laser beams have already found applications in fields such as optical tweezers and as pump...

  19. Grassmann methods in lattice field theory and statistical mechanics

    International Nuclear Information System (INIS)

    Bilgici, E.; Gattringer, C.; Huber, P.

    2006-01-01

    Full text: In two dimensions models of loops can be represented as simple Grassmann integrals. In our work we explore the generalization of these techniques to lattice field theories and statistical mechanic systems in three and four dimensions. We discuss possible strategies and applications for representations of loop and surface models as Grassmann integrals. (author)

  20. Killing vector fields in three dimensions: a method to solve massive gravity field equations

    Energy Technology Data Exchange (ETDEWEB)

    Guerses, Metin, E-mail: gurses@fen.bilkent.edu.t [Department of Mathematics, Faculty of Sciences, Bilkent University, 06800 Ankara (Turkey)

    2010-10-21

    Killing vector fields in three dimensions play an important role in the construction of the related spacetime geometry. In this work we show that when a three-dimensional geometry admits a Killing vector field then the Ricci tensor of the geometry is determined in terms of the Killing vector field and its scalars. In this way we can generate all products and covariant derivatives at any order of the Ricci tensor. Using this property we give ways to solve the field equations of topologically massive gravity (TMG) and new massive gravity (NMG) introduced recently. In particular when the scalars of the Killing vector field (timelike, spacelike and null cases) are constants then all three-dimensional symmetric tensors of the geometry, the Ricci and Einstein tensors, their covariant derivatives at all orders, and their products of all orders are completely determined by the Killing vector field and the metric. Hence, the corresponding three-dimensional metrics are strong candidates for solving all higher derivative gravitational field equations in three dimensions.

  1. Method Evaluation And Field Sample Measurements For The Rate Of Movement Of The Oxidation Front In Saltstone

    Energy Technology Data Exchange (ETDEWEB)

    Almond, P. M. [Savannah River Site (SRS), Aiken, SC (United States); Kaplan, D. I. [Savannah River Site (SRS), Aiken, SC (United States); Langton, C. A. [Savannah River Site (SRS), Aiken, SC (United States); Stefanko, D. B. [Savannah River Site (SRS), Aiken, SC (United States); Spencer, W. A. [Savannah River Site (SRS), Aiken, SC (United States); Hatfield, A. [Clemson University, Clemson, SC (United States); Arai, Y. [Clemson University, Clemson, SC (United States)

    2012-08-23

    The objective of this work was to develop and evaluate a series of methods and validate their capability to measure differences in oxidized versus reduced saltstone. Validated methods were then applied to samples cured under field conditions to simulate Performance Assessment (PA) needs for the Saltstone Disposal Facility (SDF). Four analytical approaches were evaluated using laboratory-cured saltstone samples. These methods were X-ray absorption spectroscopy (XAS), diffuse reflectance spectroscopy (DRS), chemical redox indicators, and thin-section leaching methods. XAS and thin-section leaching methods were validated as viable methods for studying oxidation movement in saltstone. Each method used samples that were spiked with chromium (Cr) as a tracer for oxidation of the saltstone. The two methods were subsequently applied to field-cured samples containing chromium to characterize the oxidation state of chromium as a function of distance from the exposed air/cementitious material surface.

  2. SPECIFIC METHOD OF RISK ASSESSMENT IN TOURISM ENTERPRISES

    Directory of Open Access Journals (Sweden)

    Andreea ARMEAN

    2014-12-01

    Full Text Available The objective of this paper is to present an innovative method of risk assessment for tourism businesses. The contribution to literature is the novelty of this method of following paths: is an ante-factum assessment not post-factum; risk assessment is based on perception rather than results; is based on specific risks tourism enterprises not on the overall risks. Is an asset-research methodology and consists in generating its own method of risk assessment based on the ideas summarized from the literature studied. The aim established is tourism enterprises from Romania. The data necessary for the application of this method will result from applying to top level management of tourism enterprises, a questionnaire about risk perception. The results from this study will help identify and measure the risks specific to tourism enterprises. The applicability of the results is to improve risk management in these enterprises.

  3. OPERATIONAL RISK IN INTERNATIONAL BUSINESS: TAXONOMY AND ASSESSMENT METHODS

    Directory of Open Access Journals (Sweden)

    Marinoiu Ana Maria

    2009-05-01

    Full Text Available The paper aims at presenting the classifications and the assessment methods for operational risk according to international regulations (ie. Basel 2, in the context of its importance as a managerial tool for international business. Considering the growin

  4. On the assessment of usability testing methods for children

    NARCIS (Netherlands)

    Markopoulos, P.; Bekker, M.M.

    2003-01-01

    The paper motivates the need to acquire methodological knowledge for involving children as test users in usability testing. It introduces a methodological framework for delineating comparative assessments of usability testing methods for children participants. This framework consists in three

  5. Power spectrum of the geomagnetic field by the maximum entropy method

    International Nuclear Information System (INIS)

    Kantor, I.J.; Trivedi, N.B.

    1980-01-01

    Monthly mean values of Vassouras (state of Rio de Janeiro) geomagnetic field are analyzed us the maximum entropy method. The method is described and compared with other methods of spectral analysis, and its advantages and disadvantages are presented. (Author) [pt

  6. Practical methods for generating alternating magnetic fields for biomedical research

    Science.gov (United States)

    Christiansen, Michael G.; Howe, Christina M.; Bono, David C.; Perreault, David J.; Anikeeva, Polina

    2017-08-01

    Alternating magnetic fields (AMFs) cause magnetic nanoparticles (MNPs) to dissipate heat while leaving surrounding tissue unharmed, a mechanism that serves as the basis for a variety of emerging biomedical technologies. Unfortunately, the challenges and costs of developing experimental setups commonly used to produce AMFs with suitable field amplitudes and frequencies present a barrier to researchers. This paper first presents a simple, cost-effective, and robust alternative for small AMF working volumes that uses soft ferromagnetic cores to focus the flux into a gap. As the experimental length scale increases to accommodate animal models (working volumes of 100s of cm3 or greater), poor thermal conductivity and volumetrically scaled core losses render that strategy ineffective. Comparatively feasible strategies for these larger volumes instead use low loss resonant tank circuits to generate circulating currents of 1 kA or greater in order to produce the comparable field amplitudes. These principles can be extended to the problem of identifying practical routes for scaling AMF setups to humans, an infrequently acknowledged challenge that influences the extent to which many applications of MNPs may ever become clinically relevant.

  7. On multiplying methods in the field of research evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Derrick, G.; Molas-Gallart, J.; De Rijcke, S.; Meijer, I.; Van der Weijden, I.; Wouters, P.

    2016-07-01

    This special session forms part of a larger program aimed at the multiplication and integration of methodological approaches in the research evaluation and innovation policy field. The session builds on previous initiatives by Gemma Derrick and colleagues at CWTS, INGENIO, the Rathenau Instituut and SPRU, exploring the advantages of qualitative methodological tools at the STI/ENID conference in Lugano, and an international workshop in London in October 2015. The program is highly topical: the research evaluation field is currently reconsidering its methodological foundations in light of new research questions arising from policy initiatives regarding a) the move toward open science; b) a reconceptualization of research excellence to include societal relevance; c) diversification of academic careers, and d) the search for indicators showcasing responsible research behavior and innovation. This new special session at STI2016 will advance and broaden the scope of previous initiatives by building bridges between cutting edge research involving quantitative, qualitative, and mixed methodological research designs. Bringing together leading experts and promising researchers with distinctive methodological skill-sets, the session will demonstrate the advantages of cross-fertilization between ‘core’ and ‘peripheral’ methodological approaches for the research evaluation and science indicators field. (Author)

  8. Self-supervised Traversability Assessment in Field Environments with Lidar and Camera

    DEFF Research Database (Denmark)

    Hansen, Mikkel Kragh; Underwood, James; Karstoft, Henrik

    , the visual classifier detects non-traversable image patches as outliers from a Gaussian Mixture Model that maintains the appearance of only traversable ground. Results Our method is evaluated using a diverse dataset of agricultural fields and orchards gathered with a perception research robot developed......Introduction The application of robotic automation within agriculture is increasing. There is a high demand for fully autonomous robots that are both efficient, reliable and affordable. In order to ensure safety, autonomous agricultural vehicles must perceive the environment and detect potential...... obstacles and threats across a variety of environmental conditions. In this paper, a self-supervised framework is proposed, combining laser range sensing from a lidar with images from a monocular camera to reliably assess terrain traversability/navigability. Methods The method uses a near-to-far approach...

  9. DREAM: a method for semi-quantitative dermal exposure assessment

    NARCIS (Netherlands)

    Wendel de Joode, B. van; Brouwer, D.H.; Kromhout, H.; Hemmen, J.J. van

    2003-01-01

    This paper describes a new method (DREAM) for structured, semi-quantitative dermal exposure assessment for chemical or biological agents that can be used in occupational hygiene or epidemiology. It is anticipated that DREAM could serve as an initial assessment of dermal exposure, amongst others,

  10. Visual art teachers and performance assessment methods in ...

    African Journals Online (AJOL)

    This paper examines the competencies of visual arts teachers in using performance assessment methods, and to ascertain the extent to which the knowledge, skills and experiences of teachers affect their competence in using assessment strategies in their classroom. The study employs a qualitative research design; ...

  11. Assessing risk of draft survey by AHP method

    Science.gov (United States)

    Xu, Guangcheng; Zhao, Kuimin; Zuo, Zhaoying; Liu, Gang; Jian, Binguo; Lin, Yan; Fan, Yukun; Wang, Fei

    2018-04-01

    The paper assesses the risks of vessel floating in the seawater for draft survey by using the analytic hierarchy process. On this basis, the paper established draft survey risk index from the view of draft reading, ballast water, fresh water, and calculation process and so on. Then the paper proposes the method to deal with risk assessment using one concrete sample.

  12. Minimal Residual Disease Assessment in Lymphoma: Methods and Applications.

    Science.gov (United States)

    Herrera, Alex F; Armand, Philippe

    2017-12-01

    Standard methods for disease response assessment in patients with lymphoma, including positron emission tomography and computed tomography scans, are imperfect. In other hematologic malignancies, particularly leukemias, the ability to detect minimal residual disease (MRD) is increasingly influencing treatment paradigms. However, in many subtypes of lymphoma, the application of MRD assessment techniques, like flow cytometry or polymerase chain reaction-based methods, has been challenging because of the absence of readily detected circulating disease or canonic chromosomal translocations. Newer MRD detection methods that use next-generation sequencing have yielded promising results in a number of lymphoma subtypes, fueling the hope that MRD detection may soon be applicable in clinical practice for most patients with lymphoma. MRD assessment can provide real-time information about tumor burden and response to therapy, noninvasive genomic profiling, and monitoring of clonal dynamics, allowing for many possible applications that could significantly affect the care of patients with lymphoma. Further validation of MRD assessment methods, including the incorporation of MRD assessment into clinical trials in patients with lymphoma, will be critical to determine how best to deploy MRD testing in routine practice and whether MRD assessment can ultimately bring us closer to the goal of personalized lymphoma care. In this review article, we describe the methods available for detecting MRD in patients with lymphoma and their relative advantages and disadvantages. We discuss preliminary results supporting the potential applications for MRD testing in the care of patients with lymphoma and strategies for including MRD assessment in lymphoma clinical trials.

  13. Dynamic life-time assessing method for the N1C700 turbine's rotor

    International Nuclear Information System (INIS)

    Popescu-Vifor, B.

    1993-01-01

    The N1C700 turbine's rotor subject to different sorts of stress variations was investigated through dynamic life-time assessing method. To obtain the temperature fields at different steam parameters inside the turbine components, a computer code named DENOPAR was developed

  14. Comparison of laboratory and field remote sensing methods to measure forage quality.

    Science.gov (United States)

    Guo, Xulin; Wilmshurst, John F; Li, Zhaoqin

    2010-09-01

    Recent research in range ecology has emphasized the importance of forage quality as a key indicator of rangeland condition. However, we lack tools to evaluate forage quality at scales appropriate for management. Using canopy reflectance data to measure forage quality has been conducted at both laboratory and field levels separately, but little work has been conducted to evaluate these methods simultaneously. The objective of this study is to find a reliable way of assessing grassland quality through measuring forage chemistry with reflectance. We studied a mixed grass ecosystem in Grasslands National Park of Canada and surrounding pastures, located in southern Saskatchewan. Spectral reflectance was collected at both in-situ field level and in the laboratory. Vegetation samples were collected at each site, sorted into the green grass portion, and then sent to a chemical company for measuring forage quality variables, including protein, lignin, ash, moisture at 135 °C, Neutral Detergent Fiber (NDF), Acid Detergent Fiber (ADF), Total Digestible, Digestible Energy, Net Energy for Lactation, Net Energy for Maintenance, and Net Energy for Gain. Reflectance data were processed with the first derivative transformation and continuum removal method. Correlation analysis was conducted on spectral and forage quality variables. A regression model was further built to investigate the possibility of using canopy spectral measurements to predict the grassland quality. Results indicated that field level prediction of protein of mixed grass species was possible (r² = 0.63). However, the relationship between canopy reflectance and the other forage quality variables was not strong.

  15. Comparison of Laboratory and Field Remote Sensing Methods to Measure Forage Quality

    Directory of Open Access Journals (Sweden)

    Zhaoqin Li

    2010-09-01

    Full Text Available Recent research in range ecology has emphasized the importance of forage quality as a key indicator of rangeland condition. However, we lack tools to evaluate forage quality at scales appropriate for management. Using canopy reflectance data to measure forage quality has been conducted at both laboratory and field levels separately, but little work has been conducted to evaluate these methods simultaneously. The objective of this study is to find a reliable way of assessing grassland quality through measuring forage chemistry with reflectance. We studied a mixed grass ecosystem in Grasslands National Park of Canada and surrounding pastures, located in southern Saskatchewan. Spectral reflectance was collected at both in-situ field level and in the laboratory. Vegetation samples were collected at each site, sorted into the green grass portion, and then sent to a chemical company for measuring forage quality variables, including protein, lignin, ash, moisture at 135 ºC, Neutral Detergent Fiber (NDF, Acid Detergent Fiber (ADF, Total Digestible, Digestible Energy, Net Energy for Lactation, Net Energy for Maintenance, and Net Energy for Gain. Reflectance data were processed with the first derivative transformation and continuum removal method. Correlation analysis was conducted on spectral and forage quality variables. A regression model was further built to investigate the possibility of using canopy spectral measurements to predict the grassland quality. Results indicated that field level prediction of protein of mixed grass species was possible (r2 = 0.63. However, the relationship between canopy reflectance and the other forage quality variables was not strong.

  16. Analysis of the most widely used Building Environmental Assessment methods

    International Nuclear Information System (INIS)

    Gu, Zhenhong; Wennersten, R.; Assefa, G.

    2006-01-01

    Building Environmental Assessment (BEA) is a term used for several methods for environmental assessment of the building environment. Generally, Life Cycle Assessment (LCA) is an important foundation and part of the BEA method, but current BEA methods form more comprehensive tools than LCA. Indicators and weight assignments are the two most important factors characterizing BEA. From the comparison of the three most widely used BEA methods, EcoHomes (BREEAM for residential buildings), LEED-NC and GBTool, it can be seen that BEA methods are shifting from ecological, indicator-based scientific systems to more integrated systems covering ecological, social and economic categories. Being relatively new methods, current BEA systems are far from perfect and are under continuous development. The further development of BEA methods will focus more on non-ecological indicators and how to promote implementation. Most BEA methods are developed based on regional regulations and LCA methods, but they do not attempt to replace these regulations. On the contrary, they try to extend implementation by incentive programmes. There are several ways to enhance BEA in the future: expand the studied scope from design levels to whole life-cycle levels of constructions, enhance international cooperation, accelerate legislation and standardize and develop user-oriented assessment systems

  17. Electrostatic field in inhomogeneous dielectric media. I. Indirect boundary element method

    International Nuclear Information System (INIS)

    Goel, N.S.; Gang, F.; Ko, Z.

    1995-01-01

    A computationally fast method is presented for calculating electrostatic field in arbitrary inhomogeneous dielectric media with open boundary condition. The method involves dividing the whole space into cubical cells and then finding effective dielectric parameters for interfacial cells consisting of several dielectrics. The electrostatic problem is then solved using either the indirect boundary element method described in this paper or the so-called volume element method described in the companion paper. Both methods are tested for accuracy by comparing the numerically calculated electrostatic fields against those analytically obtained for a dielectric sphere and dielectric ellipsoid in a uniform field and for a dielectric sphere in a point charge field

  18. Assessing Lodging Severity over an Experimental Maize (Zea mays L. Field Using UAS Images

    Directory of Open Access Journals (Sweden)

    Tianxing Chu

    2017-09-01

    Full Text Available Lodging has been recognized as one of the major destructive factors for crop quality and yield, resulting in an increasing need to develop cost-efficient and accurate methods for detecting crop lodging in a routine manner. Using structure-from-motion (SfM and novel geospatial computing algorithms, this study investigated the potential of high resolution imaging with unmanned aircraft system (UAS technology for detecting and assessing lodging severity over an experimental maize field at the Texas A&M AgriLife Research and Extension Center in Corpus Christi, Texas, during the 2016 growing season. The method was proposed to not only detect the occurrence of lodging at the field scale, but also to quantitatively estimate the number of lodged plants and the lodging rate within individual rows. Nadir-view images of the field trial were taken by multiple UAS platforms equipped with consumer grade red, green, and blue (RGB, and near-infrared (NIR cameras on a routine basis, enabling a timely observation of the plant growth until harvesting. Models of canopy structure were reconstructed via an SfM photogrammetric workflow. The UAS-estimated maize height was characterized by polygons developed and expanded from individual row centerlines, and produced reliable accuracy when compared against field measures of height obtained from multiple dates. The proposed method then segmented the individual maize rows into multiple grid cells and determined the lodging severity based on the height percentiles against preset thresholds within individual grid cells. From the analysis derived from this method, the UAS-based lodging results were generally comparable in accuracy to those measured by a human data collector on the ground, measuring the number of lodging plants (R2 = 0.48 and the lodging rate (R2 = 0.50 on a per-row basis. The results also displayed a negative relationship of ground-measured yield with UAS-estimated and ground-measured lodging rate.

  19. Methods for assessing the impact of avermectins on the decomposer community of sheep pastures.

    Science.gov (United States)

    King, K L

    1993-06-01

    This paper outlines methods which can be used in the field assessment of potentially toxic chemicals such as the avermectins. The procedures focus on measuring the effects of the drug on decomposer organisms and the nutrient cycling process in pastures grazed by sheep. Measurements of decomposer activity are described along with methods for determining dry and organic matter loss and mineral loss from dung to the underlying soil. Sampling methods for both micro- and macro-invertebrates are discussed along with determination of the percentage infection of plant roots with vesicular-arbuscular mycorrhizal fungi. An integrated sampling unit for assessing the ecotoxicity of ivermectin in pastures grazed by sheep is presented.

  20. Methods for production of aluminium powders and their application fields

    Energy Technology Data Exchange (ETDEWEB)

    Gopienko, V.G.; Kiselev, V.P.; Zobnina, N.S. (Vsesoyuznyj Nauchno-Issledovatel' skij i Proektnyj Inst. Alyuminievoj, magnievoj i ehlektrodnoj promyshlennosti (USSR))

    1984-12-01

    Different types of powder products made of alluminium and its alloys (powder, fine powders, granules and pastes) as well as their basic physicochemical properties are briefly characterized. The principle methods for alluminium powder production are outlined: physicochemical methods, the melt spraying by compressed gas being the mostly developed among them, and physico-mechanical ones. Main application spheres for powder productions of aluminium and its alloys are reported in short.

  1. Methods for production of aluminium powders and their application fields

    International Nuclear Information System (INIS)

    Gopienko, V.G.; Kiselev, V.P.; Zobnina, N.S.

    1984-01-01

    Different types of powder products made of alluminium and its alloys (powder, fine powders, granules and pastes) as well as their basic physicochemical properties are briefly characterized. The principle methods for alluminium powder production are outlined: physicochemical methods, the melt spraying by compressed gas being the mostly developed among them, and physico-mechanical ones. Main application spheres for powder productions of aluminium and its alloys are reported in short

  2. Valuation methods within the framework of life cycle assessment

    Energy Technology Data Exchange (ETDEWEB)

    Finnveden, G.

    1996-05-01

    Life Cycle Assessment Valuation methods are discussed. Different approaches for valuation are discussed as well as presently available valuation methods in relation to: * the values involved in the valuation, * the LCA framework, and * different applications of LCA. Among the conclusions are: * ethical and ideological valuations are involved not only when applying valuation weighting factors, but also when choosing valuation method and also when choosing whether to perform a valuation weighting or not, * it can be questioned whether straight distance-to-target methods are valuation methods, * it is still an open question whether presently available valuation methods produce meaningful and reliable information, * further development of quantitative valuation methods could concentrate both on different types of monetarisation methods and panel methods, * in many applications of LCA, the expected result is an identification of critical areas rather than a one-dimensional score, reducing the need for valuation methods. 88 refs, 3 figs, 4 tabs

  3. Contribution of surface analysis spectroscopic methods to the lubrication field

    International Nuclear Information System (INIS)

    Blanc, C.

    1979-01-01

    The analytical surface technics such as ESCA, AES and SIMS are tested to be applied to a particular lubrication field. One deals with a 100 C 6 steel surface innumered in tricresylphosphate at 110 0 C for 15 days. The nature of the first layers is studied after relevant solvant cleaning. An iron oxide layer is produced on the bearing surface, namely αFe 2 -O 3 . ESCA, AES and SIMS studies show an overlayer of iron phosphate. The exact nature of iron phosphate is not clearly established but the formation of a ferrous phosphate coating can be assumed from ESCA analysis [fr

  4. Low field-low cost: Can low-field magnetic resonance systems replace high-field magnetic resonance systems in the diagnostic assessment of multiple sclerosis patients?

    International Nuclear Information System (INIS)

    Ertl-Wagner, B.B.; Reith, W.; Sartor, K.

    2001-01-01

    As low-field MR imaging is becoming a widely used imaging technique, we aimed at a prospective assessment of differences in imaging quality between low- and high-field MR imaging in multiple sclerosis patients possibly interfering with diagnostic or therapeutic decision making. Twenty patients with clinically proven multiple sclerosis were examined with optimized imaging protocols in a 1.5- and a 0.23-T MR scanner within 48 h. Images were assessed independently by two neuroradiologists. No statistically significant interrater discrepancies were observed. A significantly lower number of white matter lesions could be identified in low-field MR imaging both on T1- and on T2-weighted images (T2: high field 700, low field 481; T1: high field 253, low field 177). A total of 114 enhancing lesions were discerned in the high-field MR imaging as opposed to 45 enhancing lesions in low-field MR imaging. Blood-brain barrier disruption was identified in 11 of 20 patients in the high-field MR imaging, but only in 4 of 20 patients in low-field MR imaging. Since a significantly lower lesion load is identified in low-field MR imaging than in high-field MR imaging, and blood-brain barrier disruption is frequently missed, caution must be exercised in interpreting a normal low-field MR imaging scan in a patient with clinical signs of multiple sclerosis and in interpreting a scan without enhancing lesions in a patient with known multiple sclerosis and clinical signs of exacerbation. (orig.)

  5. Implementation of visual programming methods for numerical techniques used in electromagnetic field theory

    Directory of Open Access Journals (Sweden)

    Metin Varan

    2017-08-01

    Full Text Available Field theory is one of the two sub-field theories in electrical and electronics engineering that for creates difficulties for undergraduate students. In undergraduate period, field theory has been taught under the theory of electromagnetic fields by which describes using partial differential equations and integral methods. Analytical methods for solution of field problems on the basis of a mathematical model may result the understanding difficulties for undergraduate students due to their mathematical and physical infrastructure. The analytical methods which can be applied in simple model lose their applicability to more complex models. In this case, the numerical methods are used to solve more complex equations. In this study, by preparing some field theory‘s web-based graphical user interface numerical methods of applications it has been aimed to increase learning levels of field theory problems for undergraduate and graduate students while taking in mind their computer programming capabilities.

  6. Risk assessment of nonhazardous oil-field waste disposal in salt caverns

    International Nuclear Information System (INIS)

    Elcock, D.

    1998-01-01

    In 1996, Argonne National Laboratory (ANL) conducted a preliminary technical and legal evaluation of disposing of nonhazardous oil-field wastes (NOW) into salt caverns. Argonne determined that if caverns are sited and designed well, operated carefully, closed properly, and monitored routinely, they could be suitable for disposing of oil-field wastes. On the basis of these findings, Argonne subsequently conducted a preliminary evaluation of the possibility that adverse human health effects (carcinogenic and noncarcinogenic) could result from exposure to contaminants released from the NOW disposed of in domal salt caverns. Steps used in this evaluation included the following: identifying potential contaminants of concern, determining how humans could be exposed to these contaminants, assessing contaminant toxicities, estimating contaminant intakes, and calculating human cancer and noncancer risk estimates. Five postclosure cavern release scenarios were assessed. These were inadvertent cavern intrusion, failure of the cavern seal, failure of the cavern through cracks, failure of the cavern through leaky interbeds, and a partial collapse of the cavern roof. Assuming a single, generic, salt cavern and generic oil-field wastes, potential human health effects associated with constituent hazardous substances (arsenic, benzene, cadmium, and chromium) were assessed under each of these scenarios. Preliminary results provided excess cancer risk and hazard index (referring to noncancer health effects) estimates that were well within the US Environmental Protection Agency (EPA) target range for acceptable exposure risk levels. These results led to the preliminary conclusion that from a human health perspective, salt caverns can provide an acceptable disposal method for nonhazardous oil-field wastes

  7. Risk assessment of nonhazardous oil-field waste disposal in salt caverns.

    Energy Technology Data Exchange (ETDEWEB)

    Elcock, D.

    1998-03-05

    In 1996, Argonne National Laboratory (ANL) conducted a preliminary technical and legal evaluation of disposing of nonhazardous oil-field wastes (NOW) into salt caverns. Argonne determined that if caverns are sited and designed well, operated carefully, closed properly, and monitored routinely, they could be suitable for disposing of oil-field wastes. On the basis of these findings, Argonne subsequently conducted a preliminary evaluation of the possibility that adverse human health effects (carcinogenic and noncarcinogenic) could result from exposure to contaminants released from the NOW disposed of in domal salt caverns. Steps used in this evaluation included the following: identifying potential contaminants of concern, determining how humans could be exposed to these contaminants, assessing contaminant toxicities, estimating contaminant intakes, and calculating human cancer and noncancer risk estimates. Five postclosure cavern release scenarios were assessed. These were inadvertent cavern intrusion, failure of the cavern seal, failure of the cavern through cracks, failure of the cavern through leaky interbeds, and a partial collapse of the cavern roof. Assuming a single, generic, salt cavern and generic oil-field wastes, potential human health effects associated with constituent hazardous substances (arsenic, benzene, cadmium, and chromium) were assessed under each of these scenarios. Preliminary results provided excess cancer risk and hazard index (referring to noncancer health effects) estimates that were well within the US Environmental Protection Agency (EPA) target range for acceptable exposure risk levels. These results led to the preliminary conclusion that from a human health perspective, salt caverns can provide an acceptable disposal method for nonhazardous oil-field wastes.

  8. fields

    Directory of Open Access Journals (Sweden)

    Brad J. Arnold

    2014-07-01

    Full Text Available Surface irrigation, such as flood or furrow, is the predominant form of irrigation in California for agronomic crops. Compared to other irrigation methods, however, it is inefficient in terms of water use; large quantities of water, instead of being used for crop production, are lost to excess deep percolation and tail runoff. In surface-irrigated fields, irrigators commonly cut off the inflow of water when the water advance reaches a familiar or convenient location downfield, but this experience-based strategy has not been very successful in reducing the tail runoff water. Our study compared conventional cutoff practices to a retroactively applied model-based cutoff method in four commercially producing alfalfa fields in Northern California, and evaluated the model using a simple sensor system for practical application in typical alfalfa fields. These field tests illustrated that the model can be used to reduce tail runoff in typical surface-irrigated fields, and using it with a wireless sensor system saves time and labor as well as water.

  9. Field assessment of a model tuberculosis outbreak response plan for low-incidence areas

    Directory of Open Access Journals (Sweden)

    Pascopella Lisa

    2007-10-01

    Full Text Available Abstract Background For a regional project in four low-incidence states, we designed a customizable tuberculosis outbreak response plan. Prior to dissemination of the plan, a tuberculosis outbreak occurred, presenting an opportunity to perform a field assessment of the plan. The purpose of the assessment was to ensure that the plan included essential elements to help public health professionals recognize and respond to outbreaks. Methods We designed a semi-structured questionnaire and interviewed all key stakeholders involved in the response. We used common themes to assess validity of and identify gaps in the plan. A subset of participants provided structured feedback on the plan. Results We interviewed 11 public health and six community stakeholders. The assessment demonstrated that (1 almost all of the main response activities were reflected in the plan; (2 the plan added value by providing a definition of a tuberculosis outbreak and guidelines for communication and evaluation. These were areas that lacked written protocols during the actual outbreak response; and (3 basic education about tuberculosis and the interpretation and use of genotyping data were important needs. Stakeholders also suggested adding to the plan questions for evaluation and a section for specific steps to take when an outbreak is suspected. Conclusion An interactive field assessment of a programmatic tool revealed the value of a systematic outbreak response plan with a standard definition of a tuberculosis outbreak, guidelines for communication and evaluation, and response steps. The assessment highlighted the importance of education and training for tuberculosis in low-incidence areas.

  10. [Establishment of Assessment Method for Air Bacteria and Fungi Contamination].

    Science.gov (United States)

    Zhang, Hua-ling; Yao, Da-jun; Zhang, Yu; Fang, Zi-liang

    2016-03-15

    In this paper, in order to settle existing problems in the assessment of air bacteria and fungi contamination, the indoor and outdoor air bacteria and fungi filed concentrations by impact method and settlement method in existing documents were collected and analyzed, then the goodness of chi square was used to test whether these concentration data obeyed normal distribution at the significant level of α = 0.05, and combined with the 3σ principle of normal distribution and the current assessment standards, the suggested concentrations ranges of air microbial concentrations were determined. The research results could provide a reference for developing air bacteria and fungi contamination assessment standards in the future.

  11. Accuracy Assessment Field Data for the Mariana Archipelago

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project is a cooperative effort among the National Ocean Service, National Centers for Coastal Ocean Science, Center for Coastal Monitoring and Assessment; the...

  12. Accuracy Assessment Field Data for Benthic Habitat Maps of Palau

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project is a cooperative effort among the National Ocean Service, National Centers for Coastal Ocean Science, Center for Coastal Monitoring and Assessment; the...

  13. 75 FR 6031 - Policy Paper on Revised Risk Assessment Methods for Workers, Children of Workers in Agricultural...

    Science.gov (United States)

    2010-02-05

    ... and its relationship to several other key Agency initiatives that are currently under development and... Assessment Methods for Workers, Children of Workers in Agricultural Fields, and Pesticides with No Food Uses... for comment a policy paper entitled ``Revised Risk Assessment Methods for Workers, Children of Workers...

  14. ILearning and EHomeStudy: Multimedia Training and Assessments for Field Survey Staff

    Directory of Open Access Journals (Sweden)

    Charles Loftis

    2008-04-01

    Full Text Available Survey data collection projects strive to collect high quality data from survey respondents. The quality of the data collected is greatly dependent upon the effectiveness of field interviewers (FIs to conduct inperson screenings and interviews. Training FIs and subsequently assessing their knowledge of project protocol, methods and interviewing techniques is critical to the overall success of any data collection effort. For large surveys, as the number of FIs increase, the cost of inperson training can become prohibitively large. As a cost effective solution to increase the quality of the field data, we developed a suite of web and media based training and assessment tools called iLearning and eHomeStudy for training field staff. Besides saving the project costs associated with inperson training, we are also able to provide refresher trainings throughout the year. This application also enables FIs to view standardized training courses at their convenience and at their own pace. This paper describes the technical details, key features and benefits of this application suite, and also it includes some details on user satisfaction and future directions.

  15. A probabilistic risk assessment for field radiography based on expert judgment and opinion

    International Nuclear Information System (INIS)

    Jang, Han-Ki; Ryu, Hyung-Joon; Kim, Ji-Young; Lee, Jai-Ki; Cho, Kun-Woo

    2011-01-01

    A probabilistic approach was applied to assess radiation risk associated with the field radiography using gamma sources. The Delphi method based on the expert judgments and opinions was used in the process of characterization of parameters affecting risk, which are inevitably subject to large uncertainties. A mathematical approach applying the Bayesian inferences was employed for data processing to improve the Delphi results. This process consists of three phases: (1) setting prior distributions, (2) constructing the likelihood functions and (3) deriving the posterior distributions based on the likelihood functions. The approach for characterizing input parameters using the Bayesian inference is provided for improved risk estimates without intentional rejection of part of the data, which demonstrated utility of Bayesian updating of distributions of uncertain input parameters in PRA (Probabilistic Risk Assessment). The data analysis portion for PRA in field radiography is addressed for estimates of the parameters used to determine the frequencies and consequences of the various events modeled. In this study, radiological risks for the worker and the public member in the vicinity of the work place are estimated for field radiography system in Korea based on two-dimensional Monte Carlo Analysis (2D MCA). (author)

  16. Risk assessment of nonhazardous oil-field waste disposal in salt caverns

    International Nuclear Information System (INIS)

    Elcock, D.

    1998-01-01

    that if caverns are sited and designed well, operated carefully, closed properly, and monitored routinely, they could, from technical and legal perspectives, be suitable for disposing of oil-field wastes. On the basis of these findings, ANL subsequently conducted a preliminary risk assessment on the possibility that adverse human health effects (carcinogenic and noncarcinogenic) could result from exposure to contaminants released from the NOW disposed of in salt caverns. The methodology for the risk assessment included the following steps: identifying potential contaminants of concern; determining how humans could be exposed to these contaminants; assessing contaminant toxicities; estimating contaminant intakes; and estimating human cancer and noncancer risks. To estimate exposure routes and pathways, four postclosure cavern release scenarios were assessed. These were inadvertent cavern intrusion, failure of the cavern seal, failure of the cavern through cracks, failure of the cavern through leaky interbeds, and partial collapse of the cavern roof. Assuming a single, generic, salt cavern and generic oil-field wastes, potential human health effects associated with constituent hazardous substances (arsenic, benzene, cadmium, and chromium) were assessed under each of these scenarios. Preliminary results provided excess cancer risk and hazard index (for noncancer health effects) estimates that were well within the EPA target range for acceptable exposure risk levels. These results lead to the preliminary conclusion that from a human health perspective, salt caverns can provide an acceptable disposal method for nonhazardous oil-field wastes

  17. Risk assessment of nonhazardous oil-field waste disposal in salt caverns.

    Energy Technology Data Exchange (ETDEWEB)

    Elcock, D.

    1998-03-10

    that if caverns are sited and designed well, operated carefully, closed properly, and monitored routinely, they could, from technical and legal perspectives, be suitable for disposing of oil-field wastes. On the basis of these findings, ANL subsequently conducted a preliminary risk assessment on the possibility that adverse human health effects (carcinogenic and noncarcinogenic) could result from exposure to contaminants released from the NOW disposed of in salt caverns. The methodology for the risk assessment included the following steps: identifying potential contaminants of concern; determining how humans could be exposed to these contaminants; assessing contaminant toxicities; estimating contaminant intakes; and estimating human cancer and noncancer risks. To estimate exposure routes and pathways, four postclosure cavern release scenarios were assessed. These were inadvertent cavern intrusion, failure of the cavern seal, failure of the cavern through cracks, failure of the cavern through leaky interbeds, and partial collapse of the cavern roof. Assuming a single, generic, salt cavern and generic oil-field wastes, potential human health effects associated with constituent hazardous substances (arsenic, benzene, cadmium, and chromium) were assessed under each of these scenarios. Preliminary results provided excess cancer risk and hazard index (for noncancer health effects) estimates that were well within the EPA target range for acceptable exposure risk levels. These results lead to the preliminary conclusion that from a human health perspective, salt caverns can provide an acceptable disposal method for nonhazardous oil-field wastes.

  18. Learning Receptive Fields and Quality Lookups for Blind Quality Assessment of Stereoscopic Images.

    Science.gov (United States)

    Shao, Feng; Lin, Weisi; Wang, Shanshan; Jiang, Gangyi; Yu, Mei; Dai, Qionghai

    2016-03-01

    Blind quality assessment of 3D images encounters more new challenges than its 2D counterparts. In this paper, we propose a blind quality assessment for stereoscopic images by learning the characteristics of receptive fields (RFs) from perspective of dictionary learning, and constructing quality lookups to replace human opinion scores without performance loss. The important feature of the proposed method is that we do not need a large set of samples of distorted stereoscopic images and the corresponding human opinion scores to learn a regression model. To be more specific, in the training phase, we learn local RFs (LRFs) and global RFs (GRFs) from the reference and distorted stereoscopic images, respectively, and construct their corresponding local quality lookups (LQLs) and global quality lookups (GQLs). In the testing phase, blind quality pooling can be easily achieved by searching optimal GRF and LRF indexes from the learnt LQLs and GQLs, and the quality score is obtained by combining the LRF and GRF indexes together. Experimental results on three publicly 3D image quality assessment databases demonstrate that in comparison with the existing methods, the devised algorithm achieves high consistent alignment with subjective assessment.

  19. Assessment of hatchling egg losses and two chick sexing methods ...

    African Journals Online (AJOL)

    Assessment of hatchling egg losses and two chick sexing methods in the Nigerian indigenous chicken. ... Journal of Agricultural Research and Development ... The aim of the present study is to evaluate hatchling egg loss as well as sex determination methods at day old and sexual dimorphism over 8 weeks in Nigerian ...

  20. A field test of three LQAS designs to assess the prevalence of acute malnutrition.

    Science.gov (United States)

    Deitchler, Megan; Valadez, Joseph J; Egge, Kari; Fernandez, Soledad; Hennigan, Mary

    2007-08-01

    The conventional method for assessing the prevalence of Global Acute Malnutrition (GAM) in emergency settings is the 30 x 30 cluster-survey. This study describes alternative approaches: three Lot Quality Assurance Sampling (LQAS) designs to assess GAM. The LQAS designs were field-tested and their results compared with those from a 30 x 30 cluster-survey. Computer simulations confirmed that small clusters instead of a simple random sample could be used for LQAS assessments of GAM. Three LQAS designs were developed (33 x 6, 67 x 3, Sequential design) to assess GAM thresholds of 10, 15 and 20%. The designs were field-tested simultaneously with a 30 x 30 cluster-survey in Siraro, Ethiopia during June 2003. Using a nested study design, anthropometric, morbidity and vaccination data were collected on all children 6-59 months in sampled households. Hypothesis tests about GAM thresholds were conducted for each LQAS design. Point estimates were obtained for the 30 x 30 cluster-survey and the 33 x 6 and 67 x 3 LQAS designs. Hypothesis tests showed GAM as or =10% for the 67 x 3 and Sequential designs. Point estimates for the 33 x 6 and 67 x 3 designs were similar to those of the 30 x 30 cluster-survey for GAM (6.7%, CI = 3.2-10.2%; 8.2%, CI = 4.3-12.1%, 7.4%, CI = 4.8-9.9%) and all other indicators. The CIs for the LQAS designs were only slightly wider than the CIs for the 30 x 30 cluster-survey; yet the LQAS designs required substantially less time to administer. The LQAS designs provide statistically appropriate alternatives to the more time-consuming 30 x 30 cluster-survey. However, additional field-testing is needed using independent samples rather than a nested study design.

  1. Developing an Engineering Design Process Assessment using Mixed Methods.

    Science.gov (United States)

    Wind, Stefanie A; Alemdar, Meltem; Lingle, Jeremy A; Gale, Jessica D; Moore, Roxanne A

    Recent reforms in science education worldwide include an emphasis on engineering design as a key component of student proficiency in the Science, Technology, Engineering, and Mathematics disciplines. However, relatively little attention has been directed to the development of psychometrically sound assessments for engineering. This study demonstrates the use of mixed methods to guide the development and revision of K-12 Engineering Design Process (EDP) assessment items. Using results from a middle-school EDP assessment, this study illustrates the combination of quantitative and qualitative techniques to inform item development and revisions. Overall conclusions suggest that the combination of quantitative and qualitative evidence provides an in-depth picture of item quality that can be used to inform the revision and development of EDP assessment items. Researchers and practitioners can use the methods illustrated here to gather validity evidence to support the interpretation and use of new and existing assessments.

  2. Mathematical methods for students of physics and related fields

    CERN Document Server

    Hassani, Sadri

    2000-01-01

    Intended to follow the usual introductory physics courses, this book has the unique feature of addressing the mathematical needs of sophomores and juniors in physics, engineering and other related fields Many original, lucid, and relevant examples from the physical sciences, problems at the ends of chapters, and boxes to emphasize important concepts help guide the student through the material Beginning with reviews of vector algebra and differential and integral calculus, the book continues with infinite series, vector analysis, complex algebra and analysis, ordinary and partial differential equations Discussions of numerical analysis, nonlinear dynamics and chaos, and the Dirac delta function provide an introduction to modern topics in mathematical physics This new edition has been made more user-friendly through organization into convenient, shorter chapters Also, it includes an entirely new section on Probability and plenty of new material on tensors and integral transforms Some praise for the previous edi...

  3. Mathematical Methods For Students of Physics and Related Fields

    CERN Document Server

    Hassani, Sadri

    2009-01-01

    Intended to follow the usual introductory physics courses, this book has the unique feature of addressing the mathematical needs of sophomores and juniors in physics, engineering and other related fields. Many original, lucid, and relevant examples from the physical sciences, problems at the ends of chapters, and boxes to emphasize important concepts help guide the student through the material. Beginning with reviews of vector algebra and differential and integral calculus, the book continues with infinite series, vector analysis, complex algebra and analysis, ordinary and partial differential equations. Discussions of numerical analysis, nonlinear dynamics and chaos, and the Dirac delta function provide an introduction to modern topics in mathematical physics. This new edition has been made more user-friendly through organization into convenient, shorter chapters. Also, it includes an entirely new section on Probability and plenty of new material on tensors and integral transforms. Some praise for the previo...

  4. Assessment of anxiety in open field and elevated plus maze using infrared thermography.

    Science.gov (United States)

    Lecorps, Benjamin; Rödel, Heiko G; Féron, Christophe

    2016-04-01

    Due to their direct inaccessibility, affective states are classically assessed by gathering concomitant physiological and behavioral measures. Although such a dual approach to assess emotional states is frequently used in different species including humans, the invasiveness of procedures for physiological recordings particularly in smaller-sized animals strongly restricts their application. We used infrared thermography, a non-invasive method, to assess physiological arousal during open field and elevated plus maze tests in mice. By measuring changes in surface temperature indicative of the animals' emotional response, we aimed to improve the inherently limited and still controversial information provided by behavioral parameters commonly used in these tests. Our results showed significant and consistent thermal responses during both tests, in accordance with classical physiological responses occurring in stressful situations. Besides, we found correlations between these thermal responses and the occurrence of anxiety-related behaviors. Furthermore, initial temperatures measured at the start of each procedure (open field, elevated plus maze), which can be interpreted as a measure of the animals' initial physiological arousal, predicted the levels of activity and of anxiety-related behaviors displayed during the tests. Our results stress the strong link between physiological correlates of emotions and behaviors expressed during unconditioned fear tests. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Assessing the Accuracy of Ancestral Protein Reconstruction Methods

    OpenAIRE

    Williams, Paul D; Pollock, David D; Blackburne, Benjamin P; Goldstein, Richard A

    2006-01-01

    The phylogenetic inference of ancestral protein sequences is a powerful technique for the study of molecular evolution, but any conclusions drawn from such studies are only as good as the accuracy of the reconstruction method. Every inference method leads to errors in the ancestral protein sequence, resulting in potentially misleading estimates of the ancestral protein's properties. To assess the accuracy of ancestral protein reconstruction methods, we performed computational population evolu...

  6. The bootstrap and Bayesian bootstrap method in assessing bioequivalence

    International Nuclear Information System (INIS)

    Wan Jianping; Zhang Kongsheng; Chen Hui

    2009-01-01

    Parametric method for assessing individual bioequivalence (IBE) may concentrate on the hypothesis that the PK responses are normal. Nonparametric method for evaluating IBE would be bootstrap method. In 2001, the United States Food and Drug Administration (FDA) proposed a draft guidance. The purpose of this article is to evaluate the IBE between test drug and reference drug by bootstrap and Bayesian bootstrap method. We study the power of bootstrap test procedures and the parametric test procedures in FDA (2001). We find that the Bayesian bootstrap method is the most excellent.

  7. Comparison of three methods to assess individual skeletal maturity.

    Science.gov (United States)

    Pasciuti, Enzo; Franchi, Lorenzo; Baccetti, Tiziano; Milani, Silvano; Farronato, Giampietro

    2013-09-01

    The knowledge of facial growth and development is fundamental to determine the optimal timing for different treatment procedures in the growing patient. To analyze the reproducibility of three methods in assessing individual skeletal maturity, and to evaluate any degree of concordance among them. In all, 100 growing subjects were enrolled to test three methods: the hand-wrist, cervical vertebral maturation (CVM), and medial phalanges of the third finger method (MP3). Four operators determined the skeletal maturity of the subjects to evaluate the reproducibility of each method. After 30 days the operators repeated the analysis to assess the repeatability of each method. Finally, one operator examined all subjects' radiographs to detect any concordance among the three methods. The weighted kappa values for inter-operator variability were 0.94, 0.91, and 0.90, for the WRI, CVM, and MP3 methods, respectively. The weighted kappa values for intra-operator variability were 0.92, 0.91, and 0.92, for the WRI, CVM, and MP3 methods, respectively. The three methods revealed a high degree of repeatability and reproducibility. Complete agreement among the three methods was observed in 70% of the analyzed samples. The CVM method has the advantage of not necessitating an additional radiograph. The MP3 method is a simple and practical alternative as it requires only a standard dental x-ray device.

  8. Assessing methods to estimate emissions of non-methane organic compounds from landfills

    DEFF Research Database (Denmark)

    Saquing, Jovita M.; Chanton, Jeffrey P.; Yazdani, Ramin

    2014-01-01

    The non-methane organic compound (NMOC) emission rate is used to assess compliance with landfill gas emission regulations by the United States Environmental Protection Agency (USEPA). A recent USEPA Report (EPA/600/R-11/033) employed a ratio method to estimate speciated NMOC emissions (i...... and speciated NMOC concentration and flux data from 2012/2013 field sampling of four landfills, an unpublished landfill study, and literature data from three landfills. The ratio method worked well for landfills with thin covers (...

  9. Panel discussion on near-field coupled processes with emphasis on performance assessment

    International Nuclear Information System (INIS)

    Codell, R.B.; Baca, R.G.; Ahola, M.P.

    1996-01-01

    The presentations in this panel discussion involve the general topic of near-field coupled processes and postclosure performance assessment with an emphasis on rock mechanics. The potential impact of near-field rock mass deformation on repository performance was discussed, as well as topics including long term excavation deterioration, the performance of geologic seals, and coupled processes concerning rock mechanics in performance assessments

  10. 78 FR 29698 - Availability of an Environmental Assessment for Field Testing a Canine Lymphoma Vaccine, DNA

    Science.gov (United States)

    2013-05-21

    ...] Availability of an Environmental Assessment for Field Testing a Canine Lymphoma Vaccine, DNA AGENCY: Animal and... Canine Lymphoma Vaccine, DNA. The environmental assessment, which is based on a risk analysis prepared to... biological product: Requester: Merial, Inc. Product: Canine Lymphoma Vaccine, DNA. Possible Field Test...

  11. Reporting methods of blinding in randomized trials assessing nonpharmacological treatments.

    Directory of Open Access Journals (Sweden)

    Isabelle Boutron

    2007-02-01

    Full Text Available BACKGROUND: Blinding is a cornerstone of treatment evaluation. Blinding is more difficult to obtain in trials assessing nonpharmacological treatment and frequently relies on "creative" (nonstandard methods. The purpose of this study was to systematically describe the strategies used to obtain blinding in a sample of randomized controlled trials of nonpharmacological treatment. METHODS AND FINDINGS: We systematically searched in Medline and the Cochrane Methodology Register for randomized controlled trials (RCTs assessing nonpharmacological treatment with blinding, published during 2004 in high-impact-factor journals. Data were extracted using a standardized extraction form. We identified 145 articles, with the method of blinding described in 123 of the reports. Methods of blinding of participants and/or health care providers and/or other caregivers concerned mainly use of sham procedures such as simulation of surgical procedures, similar attention-control interventions, or a placebo with a different mode of administration for rehabilitation or psychotherapy. Trials assessing devices reported various placebo interventions such as use of sham prosthesis, identical apparatus (e.g., identical but inactivated machine or use of activated machine with a barrier to block the treatment, or simulation of using a device. Blinding participants to the study hypothesis was also an important method of blinding. The methods reported for blinding outcome assessors relied mainly on centralized assessment of paraclinical examinations, clinical examinations (i.e., use of video, audiotape, photography, or adjudications of clinical events. CONCLUSIONS: This study classifies blinding methods and provides a detailed description of methods that could overcome some barriers of blinding in clinical trials assessing nonpharmacological treatment, and provides information for readers assessing the quality of results of such trials.

  12. Field Testing of Compartmentalization Methods for Multifamily Construction

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, K. [Building Science Corporation, Westford, MA (United States); Lstiburek, J. [Building Science Corporation, Westford, MA (United States)

    2015-03-01

    The 2012 IECC has an airtightness requirement of 3 air changes per hour at 50 Pascals test pressure for both single-family and multifamily construction in Climate Zones 3-8. Other programs (LEED, ASHRAE 189, ASHRAE 62.2) have similar or tighter compartmentalization requirements, driving the need for easier and more effective methods of compartmentalization in multifamily buildings. Builders and practitioners have found that fire-resistance rated wall assemblies are a major source of difficulty in air sealing/compartmentalization, particularly in townhouse construction. This problem is exacerbated when garages are “tucked in” to the units and living space is located over the garages. In this project, Building Science Corporation examined the taping of exterior sheathing details to improve air sealing results in townhouse and multifamily construction, when coupled with a better understanding of air leakage pathways. Current approaches are cumbersome, expensive, time consuming, and ineffective; these details were proposed as a more effective and efficient method. The effectiveness of these air sealing methods was tested with blower door testing, including “nulled” or “guarded” testing (adjacent units run at equal test pressure to null out inter-unit air leakage, or “pressure neutralization”). Pressure diagnostics were used to evaluate unit-to-unit connections and series leakage pathways (i.e., air leakage from exterior, into the fire-resistance rated wall assembly, and to the interior).

  13. Numerical Exposure Assessment Method for Low Frequency Range and Application to Wireless Power Transfer.

    Directory of Open Access Journals (Sweden)

    SangWook Park

    Full Text Available In this paper, a numerical exposure assessment method is presented for a quasi-static analysis by the use of finite-difference time-domain (FDTD algorithm. The proposed method is composed of scattered field FDTD method and quasi-static approximation for analyzing of the low frequency band electromagnetic problems. The proposed method provides an effective tool to compute induced electric fields in an anatomically realistic human voxel model exposed to an arbitrary non-uniform field source in the low frequency ranges. The method is verified, and excellent agreement with theoretical solutions is found for a dielectric sphere model exposed to a magnetic dipole source. The assessment method serves a practical example of the electric fields, current densities, and specific absorption rates induced in a human head and body in close proximity to a 150-kHz wireless power transfer system for cell phone charging. The results are compared to the limits recommended by the International Commission on Non-Ionizing Radiation Protection (ICNIRP and the IEEE standard guidelines.

  14. Numerical Exposure Assessment Method for Low Frequency Range and Application to Wireless Power Transfer

    Science.gov (United States)

    Kim, Minhyuk

    2016-01-01

    In this paper, a numerical exposure assessment method is presented for a quasi-static analysis by the use of finite-difference time-domain (FDTD) algorithm. The proposed method is composed of scattered field FDTD method and quasi-static approximation for analyzing of the low frequency band electromagnetic problems. The proposed method provides an effective tool to compute induced electric fields in an anatomically realistic human voxel model exposed to an arbitrary non-uniform field source in the low frequency ranges. The method is verified, and excellent agreement with theoretical solutions is found for a dielectric sphere model exposed to a magnetic dipole source. The assessment method serves a practical example of the electric fields, current densities, and specific absorption rates induced in a human head and body in close proximity to a 150-kHz wireless power transfer system for cell phone charging. The results are compared to the limits recommended by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and the IEEE standard guidelines. PMID:27898688

  15. Numerical Exposure Assessment Method for Low Frequency Range and Application to Wireless Power Transfer.

    Science.gov (United States)

    Park, SangWook; Kim, Minhyuk

    2016-01-01

    In this paper, a numerical exposure assessment method is presented for a quasi-static analysis by the use of finite-difference time-domain (FDTD) algorithm. The proposed method is composed of scattered field FDTD method and quasi-static approximation for analyzing of the low frequency band electromagnetic problems. The proposed method provides an effective tool to compute induced electric fields in an anatomically realistic human voxel model exposed to an arbitrary non-uniform field source in the low frequency ranges. The method is verified, and excellent agreement with theoretical solutions is found for a dielectric sphere model exposed to a magnetic dipole source. The assessment method serves a practical example of the electric fields, current densities, and specific absorption rates induced in a human head and body in close proximity to a 150-kHz wireless power transfer system for cell phone charging. The results are compared to the limits recommended by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) and the IEEE standard guidelines.

  16. New mobile methods for dietary assessment: review of image-assisted and image-based dietary assessment methods.

    Science.gov (United States)

    Boushey, C J; Spoden, M; Zhu, F M; Delp, E J; Kerr, D A

    2017-08-01

    For nutrition practitioners and researchers, assessing dietary intake of children and adults with a high level of accuracy continues to be a challenge. Developments in mobile technologies have created a role for images in the assessment of dietary intake. The objective of this review was to examine peer-reviewed published papers covering development, evaluation and/or validation of image-assisted or image-based dietary assessment methods from December 2013 to January 2016. Images taken with handheld devices or wearable cameras have been used to assist traditional dietary assessment methods for portion size estimations made by dietitians (image-assisted methods). Image-assisted approaches can supplement either dietary records or 24-h dietary recalls. In recent years, image-based approaches integrating application technology for mobile devices have been developed (image-based methods). Image-based approaches aim at capturing all eating occasions by images as the primary record of dietary intake, and therefore follow the methodology of food records. The present paper reviews several image-assisted and image-based methods, their benefits and challenges; followed by details on an image-based mobile food record. Mobile technology offers a wide range of feasible options for dietary assessment, which are easier to incorporate into daily routines. The presented studies illustrate that image-assisted methods can improve the accuracy of conventional dietary assessment methods by adding eating occasion detail via pictures captured by an individual (dynamic images). All of the studies reduced underreporting with the help of images compared with results with traditional assessment methods. Studies with larger sample sizes are needed to better delineate attributes with regards to age of user, degree of error and cost.

  17. ILO activities in the field of risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Pinnagoda, C [Occupational Safety and Health Branch, Working Conditions and Environment Department, International Labor Organization, Geneva (Switzerland)

    1992-07-01

    Control of chemical risks has become a matter of increasing concern for the occupational safety and health activities of the ILO. Its chemical safety programme focuses attention on a series of comprehensive measures to promote national level action for effective control of chemical risks aimed at the protection of workers and consequently of the general public. The supply and use of information based on risk assessment for exposure control and the application of practical improvement measures through improved risk management and training continue to receive increasing importance. The important and direct role of employers and workers in the assessment of risks and planning and implementation of workplace improvements is an identified need. Risk assessment is a component of the chemical safety programme of the ILO that places significant emphasis on: the setting of international standards that lay down basic principles in chemical risk assessment and control; national level action to promote coherent policies and programmes on safety in the use of chemicals and prevention of industrial disasters (major hazard control); technical advisory services through the development of guides and training programmes that focus on workplace participatory approaches; collection and dissemination of practical information; and technical co-operation assistance to developing countries.

  18. ILO activities in the field of risk assessment

    International Nuclear Information System (INIS)

    Pinnagoda, C.

    1992-01-01

    Control of chemical risks has become a matter of increasing concern for the occupational safety and health activities of the ILO. Its chemical safety programme focuses attention on a series of comprehensive measures to promote national level action for effective control of chemical risks aimed at the protection of workers and consequently of the general public. The supply and use of information based on risk assessment for exposure control and the application of practical improvement measures through improved risk management and training continue to receive increasing importance. The important and direct role of employers and workers in the assessment of risks and planning and implementation of workplace improvements is an identified need. Risk assessment is a component of the chemical safety programme of the ILO that places significant emphasis on: the setting of international standards that lay down basic principles in chemical risk assessment and control; national level action to promote coherent policies and programmes on safety in the use of chemicals and prevention of industrial disasters (major hazard control); technical advisory services through the development of guides and training programmes that focus on workplace participatory approaches; collection and dissemination of practical information; and technical co-operation assistance to developing countries

  19. Cardiovascular fluid dynamics. Methods for flow and pressure field analysis from magnetic resonance imaging

    International Nuclear Information System (INIS)

    Ebbers, T.

    2001-01-01

    Cardiovascular blood flow is highly complex and incompletely understood. Blood flow patterns are expected to influence the opening and closing of normal and prosthetic heart valves, the efficiency of cardiac filling and ejection, and the resistance to thrombus formation within the heart. Conventional diagnostic techniques are poorly suited to the study of the three-dimensional (3D) blood flow patterns in the heart chambers and large vessels. Noninvasive methods have also been inadequate in studying intracardiac pressure differences, which are the driving force of flow and are critical in the evaluation of many cardiovascular abnormalities. This thesis focuses on the development of non-invasive methods for analysis of 3D cardiovascular blood flow. Simultaneous study of cardiovascular fluid dynamics allowed knowledge exchange across the two disciplines, facilitating the development process and broadening the applicability of the methods. A time-resolved 3D phase-contrast Magnetic Resonance Imaging (MRI) technique was used to acquire the velocity vector field in a 3D volume encompassing the entire heart or a large vessel. Cardiovascular blood flow patterns were visualized by use of particle traces, which revealed, for instance, vortical flow patterns in the left atrium. By applying the Navier-Stokes equation along a user-defined line in the 3D velocity vector field, the relative pressure could be obtained as an excellent supplement to the flow pattern visualization. Using a delineation of the blood pool, the time-varying 3D relative pressure field in the human left ventricle was obtained from the velocity field by use of the pressure Poisson equation. A delineation of the heart muscle, a task that is almost impossible to perform on 3D MRI either automatically or manually, was also achieved by usage of particle traces. This segmentation allows automatic calculation of the 3D relative pressure field, as well as calculation of well-established parameters such as

  20. Cardiovascular fluid dynamics. Methods for flow and pressure field analysis from magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Ebbers, T

    2001-05-01

    Cardiovascular blood flow is highly complex and incompletely understood. Blood flow patterns are expected to influence the opening and closing of normal and prosthetic heart valves, the efficiency of cardiac filling and ejection, and the resistance to thrombus formation within the heart. Conventional diagnostic techniques are poorly suited to the study of the three-dimensional (3D) blood flow patterns in the heart chambers and large vessels. Noninvasive methods have also been inadequate in studying intracardiac pressure differences, which are the driving force of flow and are critical in the evaluation of many cardiovascular abnormalities. This thesis focuses on the development of non-invasive methods for analysis of 3D cardiovascular blood flow. Simultaneous study of cardiovascular fluid dynamics allowed knowledge exchange across the two disciplines, facilitating the development process and broadening the applicability of the methods. A time-resolved 3D phase-contrast Magnetic Resonance Imaging (MRI) technique was used to acquire the velocity vector field in a 3D volume encompassing the entire heart or a large vessel. Cardiovascular blood flow patterns were visualized by use of particle traces, which revealed, for instance, vortical flow patterns in the left atrium. By applying the Navier-Stokes equation along a user-defined line in the 3D velocity vector field, the relative pressure could be obtained as an excellent supplement to the flow pattern visualization. Using a delineation of the blood pool, the time-varying 3D relative pressure field in the human left ventricle was obtained from the velocity field by use of the pressure Poisson equation. A delineation of the heart muscle, a task that is almost impossible to perform on 3D MRI either automatically or manually, was also achieved by usage of particle traces. This segmentation allows automatic calculation of the 3D relative pressure field, as well as calculation of well-established parameters such as

  1. Pressure test method for reactor pressure vessel in construction field

    International Nuclear Information System (INIS)

    Takeda, Masakado; Ushiroda, Koichi; Miyahara, Ryohei; Takano, Hiroshi; Matsuura, Tadashi; Sato, Keiya.

    1998-01-01

    Plant constitutional parts as targets of both of a primary pressure test and a secondary pressure test are disposed in communication with a reactor pressure vessel, and a pressure of the primary pressure test is applied to the targets of both tests, so that the primary pressure test and the second pressure test are conducted together. Since the number of pressure tests can be reduced to promote construction, and the number of workers can also be reduced. A pressure exceeding the maximum pressure upon use is applied to the pressure vessel after disposing the incore structures, to continuously conduct the primary pressure test and the secondary pressure test joined together and an incore flowing test while closing the upper lid of the pressure vessel as it is in the construction field. The number of opening/closing of the upper lid upon conducting every test can be reduced, and since the pressure resistance test is conducted after arranging circumference conditions for the incore flowing test, the tests can be conducted collectively also in view of time. (N.H.)

  2. Method and system for progressive mesh storage and reconstruction using wavelet-encoded height fields

    Science.gov (United States)

    Baxes, Gregory A. (Inventor); Linger, Timothy C. (Inventor)

    2011-01-01

    Systems and methods are provided for progressive mesh storage and reconstruction using wavelet-encoded height fields. A method for progressive mesh storage includes reading raster height field data, and processing the raster height field data with a discrete wavelet transform to generate wavelet-encoded height fields. In another embodiment, a method for progressive mesh storage includes reading texture map data, and processing the texture map data with a discrete wavelet transform to generate wavelet-encoded texture map fields. A method for reconstructing a progressive mesh from wavelet-encoded height field data includes determining terrain blocks, and a level of detail required for each terrain block, based upon a viewpoint. Triangle strip constructs are generated from vertices of the terrain blocks, and an image is rendered utilizing the triangle strip constructs. Software products that implement these methods are provided.

  3. A comparison between progressive extension method (PEM) and iterative method (IM) for magnetic field extrapolations in the solar atmosphere

    Science.gov (United States)

    Wu, S. T.; Sun, M. T.; Sakurai, Takashi

    1990-01-01

    This paper presents a comparison between two numerical methods for the extrapolation of nonlinear force-free magnetic fields, viz the Iterative Method (IM) and the Progressive Extension Method (PEM). The advantages and disadvantages of these two methods are summarized, and the accuracy and numerical instability are discussed. On the basis of this investigation, it is claimed that the two methods do resemble each other qualitatively.

  4. An Integrated Method of Supply Chains Vulnerability Assessment

    Directory of Open Access Journals (Sweden)

    Jiaguo Liu

    2016-01-01

    Full Text Available Supply chain vulnerability identification and evaluation are extremely important to mitigate the supply chain risk. We present an integrated method to assess the supply chain vulnerability. The potential failure mode of the supply chain vulnerability is analyzed through the SCOR model. Combining the fuzzy theory and the gray theory, the correlation degree of each vulnerability indicator can be calculated and the target improvements can be carried out. In order to verify the effectiveness of the proposed method, we use Kendall’s tau coefficient to measure the effect of different methods. The result shows that the presented method has the highest consistency in the assessment compared with the other two methods.

  5. Assessing and evaluating multidisciplinary translational teams: a mixed methods approach.

    Science.gov (United States)

    Wooten, Kevin C; Rose, Robert M; Ostir, Glenn V; Calhoun, William J; Ameredes, Bill T; Brasier, Allan R

    2014-03-01

    A case report illustrates how multidisciplinary translational teams can be assessed using outcome, process, and developmental types of evaluation using a mixed-methods approach. Types of evaluation appropriate for teams are considered in relation to relevant research questions and assessment methods. Logic models are applied to scientific projects and team development to inform choices between methods within a mixed-methods design. Use of an expert panel is reviewed, culminating in consensus ratings of 11 multidisciplinary teams and a final evaluation within a team-type taxonomy. Based on team maturation and scientific progress, teams were designated as (a) early in development, (b) traditional, (c) process focused, or (d) exemplary. Lessons learned from data reduction, use of mixed methods, and use of expert panels are explored.

  6. Field Testing of Compartmentalization Methods for Multifamily Construction

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, K. [Building Science Corporation, Westford, MA (United States); Lstiburek, J. W. [Building Science Corporation, Westford, MA (United States)

    2015-03-01

    The 2012 International Energy Conservation Code (IECC) has an airtightness requirement of 3 air changes per hour at 50 Pascals test pressure (3 ACH50) for single-family and multifamily construction (in climate zones 3–8). The Leadership in Energy & Environmental Design certification program and ASHRAE Standard 189 have comparable compartmentalization requirements. ASHRAE Standard 62.2 will soon be responsible for all multifamily ventilation requirements (low rise and high rise); it has an exceptionally stringent compartmentalization requirement. These code and program requirements are driving the need for easier and more effective methods of compartmentalization in multifamily buildings.

  7. Generalized spectral method for near-field optical microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, B.-Y.; Zhang, L. M.; Basov, D. N.; Fogler, M. M. [Department of Physics, University of California San Diego, 9500 Gilman Drive, La Jolla, California 92093 (United States); Castro Neto, A. H. [Department of Physics, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215 (United States); Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, Singapore, Singapore 117542 (Singapore)

    2016-02-07

    Electromagnetic interaction between a sub-wavelength particle (the “probe”) and a material surface (the “sample”) is studied theoretically. The interaction is shown to be governed by a series of resonances corresponding to surface polariton modes localized near the probe. The resonance parameters depend on the dielectric function and geometry of the probe as well as on the surface reflectivity of the material. Calculation of such resonances is carried out for several types of axisymmetric probes: spherical, spheroidal, and pear-shaped. For spheroids, an efficient numerical method is developed, capable of handling cases of large or strongly momentum-dependent surface reflectivity. Application of the method to highly resonant materials, such as aluminum oxide (by itself or covered with graphene), reveals a rich structure of multi-peak spectra and nonmonotonic approach curves, i.e., the probe-sample distance dependence. These features also strongly depend on the probe shape and optical constants of the model. For less resonant materials such as silicon oxide, the dependence is weak, so that the spheroidal model is reliable. The calculations are done within the quasistatic approximation with radiative damping included perturbatively.

  8. 3D modeling of the total electric field induced by transcranial magnetic stimulation using the boundary element method

    Energy Technology Data Exchange (ETDEWEB)

    Salinas, F S; Lancaster, J L; Fox, P T [Research Imaging Center, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229 (United States)

    2009-06-21

    Transcranial magnetic stimulation (TMS) delivers highly localized brain stimulations via non-invasive externally applied magnetic fields. This non-invasive, painless technique provides researchers and clinicians with a unique tool capable of stimulating both the central and peripheral nervous systems. However, a complete analysis of the macroscopic electric fields produced by TMS has not yet been performed. In this paper, we addressed the importance of the secondary E-field created by surface charge accumulation during TMS using the boundary element method (BEM). 3D models were developed using simple head geometries in order to test the model and compare it with measured values. The effects of tissue geometry, size and conductivity were also investigated. Finally, a realistically shaped head model was used to assess the effect of multiple surfaces on the total E-field. Secondary E-fields have the greatest impact at areas in close proximity to each tissue layer. Throughout the head, the secondary E-field magnitudes typically range from 20% to 35% of the primary E-field's magnitude. The direction of the secondary E-field was generally in opposition to the primary E-field; however, for some locations, this was not the case (i.e. going from high to low conductivity tissues). These findings show that realistically shaped head geometries are important for accurate modeling of the total E-field.

  9. 3D modeling of the total electric field induced by transcranial magnetic stimulation using the boundary element method

    International Nuclear Information System (INIS)

    Salinas, F S; Lancaster, J L; Fox, P T

    2009-01-01

    Transcranial magnetic stimulation (TMS) delivers highly localized brain stimulations via non-invasive externally applied magnetic fields. This non-invasive, painless technique provides researchers and clinicians with a unique tool capable of stimulating both the central and peripheral nervous systems. However, a complete analysis of the macroscopic electric fields produced by TMS has not yet been performed. In this paper, we addressed the importance of the secondary E-field created by surface charge accumulation during TMS using the boundary element method (BEM). 3D models were developed using simple head geometries in order to test the model and compare it with measured values. The effects of tissue geometry, size and conductivity were also investigated. Finally, a realistically shaped head model was used to assess the effect of multiple surfaces on the total E-field. Secondary E-fields have the greatest impact at areas in close proximity to each tissue layer. Throughout the head, the secondary E-field magnitudes typically range from 20% to 35% of the primary E-field's magnitude. The direction of the secondary E-field was generally in opposition to the primary E-field; however, for some locations, this was not the case (i.e. going from high to low conductivity tissues). These findings show that realistically shaped head geometries are important for accurate modeling of the total E-field.

  10. 3D modeling of the total electric field induced by transcranial magnetic stimulation using the boundary element method

    Science.gov (United States)

    Salinas, F. S.; Lancaster, J. L.; Fox, P. T.

    2009-06-01

    Transcranial magnetic stimulation (TMS) delivers highly localized brain stimulations via non-invasive externally applied magnetic fields. This non-invasive, painless technique provides researchers and clinicians with a unique tool capable of stimulating both the central and peripheral nervous systems. However, a complete analysis of the macroscopic electric fields produced by TMS has not yet been performed. In this paper, we addressed the importance of the secondary E-field created by surface charge accumulation during TMS using the boundary element method (BEM). 3D models were developed using simple head geometries in order to test the model and compare it with measured values. The effects of tissue geometry, size and conductivity were also investigated. Finally, a realistically shaped head model was used to assess the effect of multiple surfaces on the total E-field. Secondary E-fields have the greatest impact at areas in close proximity to each tissue layer. Throughout the head, the secondary E-field magnitudes typically range from 20% to 35% of the primary E-field's magnitude. The direction of the secondary E-field was generally in opposition to the primary E-field; however, for some locations, this was not the case (i.e. going from high to low conductivity tissues). These findings show that realistically shaped head geometries are important for accurate modeling of the total E-field.

  11. A field method for soil erosion measurements in agricultural and natural lands

    Science.gov (United States)

    Y.P. Hsieh; K.T. Grant; G.C. Bugna

    2009-01-01

    Soil erosion is one of the most important watershed processes in nature, yet quantifying it under field conditions remains a challenge. The lack of soil erosion field data is a major factor hindering our ability to predict soil erosion in a watershed. We present here the development of a simple and sensitive field method that quantifies soil erosion and the resulting...

  12. Near-to far-field transformation in the aperiodic Fourier modal method

    NARCIS (Netherlands)

    Rook, R.; Pisarenco, M.; Setija, I.D.

    2013-01-01

    This paper addresses the task of obtaining the far-field spectrum for a finite structure given the near-field calculated by the aperiodic Fourier modal method in contrast-field formulation (AFMM-CFF). The AFMM-CFF efficiently calculates the solution to Maxwell's equations for a finite structure by

  13. NMR system and method having a permanent magnet providing a rotating magnetic field

    Science.gov (United States)

    Schlueter, Ross D [Berkeley, CA; Budinger, Thomas F [Berkeley, CA

    2009-05-19

    Disclosed herein are systems and methods for generating a rotating magnetic field. The rotating magnetic field can be used to obtain rotating-field NMR spectra, such as magic angle spinning spectra, without having to physically rotate the sample. This result allows magic angle spinning NMR to be conducted on biological samples such as live animals, including humans.

  14. Companies Credit Risk Assessment Methods for Investment Decision Making

    Directory of Open Access Journals (Sweden)

    Dovilė Peškauskaitė

    2017-06-01

    Full Text Available As the banks have tightened lending requirements, companies look for alternative sources of external funding. One of such is bonds issue. Unfortunately, corporate bonds issue as a source of funding is rare in Lithuania. This occurs because companies face with a lack of information, investors fear to take on credit risk. Credit risk is defined as a borrower’s failure to meet its obligation. Investors, in order to avoid credit risk, have to assess the state of the companies. The goal of the article is to determine the most informative methods of credit risk assessment. The article summarizes corporate lending sources, analyzes corporate default causes and credit risk assessment methods. The study based on the SWOT analysis shows that investors before making an investment decision should evaluate both the business risk,using qualitative method CAMPARI, and the financial risk, using financial ratio analysis.

  15. Use of economics methods in the field of radioactive wastes

    International Nuclear Information System (INIS)

    Lepine, Jacques.

    1981-01-01

    The broad principles of the discounted cash flow system which consists in introducing the time factor into the economic calculations are presented. The discounted cash flow (DCF) rate of return corresponds to the global balance between the offer of and demand for capital or between savings and investments. Examples of applications are given: DCF average cost of the nuclear kWh, the cubic metre of stored waste and the cubic metre saved by a reduction on volume. Optimisation is considered: that is to say the total DCF cost minimum of the processing, transport and storage of waste line. The method is limited by other criteria: safety, protection against radiations, political aspects. Nevertheless, it is useful to know their economic impact to avoid reaching prohibitive costs and to ensure that the decisions to come are consistent with those taken in the past [fr

  16. An analytical-numerical comprehensive method for optimizing the fringing magnetic field

    International Nuclear Information System (INIS)

    Xiao Meiqin; Mao Naifeng

    1991-01-01

    The criterion of optimizing the fringing magnetic field is discussed, and an analytical-numerical comprehensive method for realizing the optimization is introduced. The method mentioned above consists of two parts, the analytical part calculates the field of the shims, which corrects the fringing magnetic field by using uniform magnetizing method; the numerical part fulfils the whole calculation of the field distribution by solving the equation of magnetic vector potential A within the region covered by arbitrary triangular meshes with the aid of finite difference method and successive over relaxation method. On the basis of the method, the optimization of the fringing magnetic field for a large-scale electromagnetic isotope separator is finished

  17. Assessment of outdoor radiofrequency electromagnetic field exposure through hotspot localization using kriging-based sequential sampling.

    Science.gov (United States)

    Aerts, Sam; Deschrijver, Dirk; Verloock, Leen; Dhaene, Tom; Martens, Luc; Joseph, Wout

    2013-10-01

    In this study, a novel methodology is proposed to create heat maps that accurately pinpoint the outdoor locations with elevated exposure to radiofrequency electromagnetic fields (RF-EMF) in an extensive urban region (or, hotspots), and that would allow local authorities and epidemiologists to efficiently assess the locations and spectral composition of these hotspots, while at the same time developing a global picture of the exposure in the area. Moreover, no prior knowledge about the presence of radiofrequency radiation sources (e.g., base station parameters) is required. After building a surrogate model from the available data using kriging, the proposed method makes use of an iterative sampling strategy that selects new measurement locations at spots which are deemed to contain the most valuable information-inside hotspots or in search of them-based on the prediction uncertainty of the model. The method was tested and validated in an urban subarea of Ghent, Belgium with a size of approximately 1 km2. In total, 600 input and 50 validation measurements were performed using a broadband probe. Five hotspots were discovered and assessed, with maximum total electric-field strengths ranging from 1.3 to 3.1 V/m, satisfying the reference levels issued by the International Commission on Non-Ionizing Radiation Protection for exposure of the general public to RF-EMF. Spectrum analyzer measurements in these hotspots revealed five radiofrequency signals with a relevant contribution to the exposure. The radiofrequency radiation emitted by 900 MHz Global System for Mobile Communications (GSM) base stations was always dominant, with contributions ranging from 45% to 100%. Finally, validation of the subsequent surrogate models shows high prediction accuracy, with the final model featuring an average relative error of less than 2dB (factor 1.26 in electric-field strength), a correlation coefficient of 0.7, and a specificity of 0.96. Copyright © 2013 Elsevier Inc. All rights

  18. Probabilistic tsunami hazard assessment at Seaside, Oregon, for near-and far-field seismic sources

    Science.gov (United States)

    Gonzalez, F.I.; Geist, E.L.; Jaffe, B.; Kanoglu, U.; Mofjeld, H.; Synolakis, C.E.; Titov, V.V.; Areas, D.; Bellomo, D.; Carlton, D.; Horning, T.; Johnson, J.; Newman, J.; Parsons, T.; Peters, R.; Peterson, C.; Priest, G.; Venturato, A.; Weber, J.; Wong, F.; Yalciner, A.

    2009-01-01

    The first probabilistic tsunami flooding maps have been developed. The methodology, called probabilistic tsunami hazard assessment (PTHA), integrates tsunami inundation modeling with methods of probabilistic seismic hazard assessment (PSHA). Application of the methodology to Seaside, Oregon, has yielded estimates of the spatial distribution of 100- and 500-year maximum tsunami amplitudes, i.e., amplitudes with 1% and 0.2% annual probability of exceedance. The 100-year tsunami is generated most frequently by far-field sources in the Alaska-Aleutian Subduction Zone and is characterized by maximum amplitudes that do not exceed 4 m, with an inland extent of less than 500 m. In contrast, the 500-year tsunami is dominated by local sources in the Cascadia Subduction Zone and is characterized by maximum amplitudes in excess of 10 m and an inland extent of more than 1 km. The primary sources of uncertainty in these results include those associated with interevent time estimates, modeling of background sea level, and accounting for temporal changes in bathymetry and topography. Nonetheless, PTHA represents an important contribution to tsunami hazard assessment techniques; viewed in the broader context of risk analysis, PTHA provides a method for quantifying estimates of the likelihood and severity of the tsunami hazard, which can then be combined with vulnerability and exposure to yield estimates of tsunami risk. Copyright 2009 by the American Geophysical Union.

  19. A comprehensive environmental impact assessment method for shale gas development

    Directory of Open Access Journals (Sweden)

    Renjin Sun

    2015-03-01

    Full Text Available The great success of US commercial shale gas exploitation stimulates the shale gas development in China, subsequently, the corresponding supporting policies were issued in the 12th Five-Year Plan. But from the experience in the US shale gas development, we know that the resulted environmental threats are always an unavoidable issue, but no uniform and standard evaluation system has yet been set up in China. The comprehensive environment refers to the combination of natural ecological environment and external macro-environment. In view of this, we conducted a series of studies on how to set up a comprehensive environmental impact assessment system as well as the related evaluation methodology and models. First, we made an in-depth investigation into shale gas development procedures and any possible environmental impacts, and then compared, screened and modified environmental impact assessment methods for shale gas development. Also, we established an evaluating system and assessment models according to different status of the above two types of environment: the correlation matrix method was employed to assess the impacts on natural ecological environment and the optimization distance method was modified to evaluate the impacts on external macro-environment. Finally, we substitute the two subindexes into the comprehensive environmental impact assessment model and achieved the final numerical result of environmental impact assessment. This model can be used to evaluate if a shale gas project has any impact on environment, compare the impacts before and after a shale gas development project, or the impacts of different projects.

  20. In-field analysis and assessment of nuclear material

    International Nuclear Information System (INIS)

    Morgado, R.E.; Myers, W.S.; Olivares, J.A.; Phillips, J.R.; York, R.L.

    1996-01-01

    Los Alamos National Laboratory has actively developed and implemented a number of instruments to monitor, detect, and analyze nuclear materials in the field. Many of these technologies, developed under existing US Department of Energy programs, can also be used to effectively interdict nuclear materials smuggled across or within national borders. In particular, two instruments are suitable for immediate implementation: the NAVI-2, a hand-held gamma-ray and neutron system for the detection and rapid identification of radioactive materials, and the portable mass spectrometer for the rapid analysis of minute quantities of radioactive materials. Both instruments provide not only critical information about the characteristics of the nuclear material for law-enforcement agencies and national authorities but also supply health and safety information for personnel handling the suspect materials

  1. Safety assessment and detection methods of genetically modified organisms.

    Science.gov (United States)

    Xu, Rong; Zheng, Zhe; Jiao, Guanglian

    2014-01-01

    Genetically modified organisms (GMOs), are gaining importance in agriculture as well as the production of food and feed. Along with the development of GMOs, health and food safety concerns have been raised. These concerns for these new GMOs make it necessary to set up strict system on food safety assessment of GMOs. The food safety assessment of GMOs, current development status of safety and precise transgenic technologies and GMOs detection have been discussed in this review. The recent patents about GMOs and their detection methods are also reviewed. This review can provide elementary introduction on how to assess and detect GMOs.

  2. Comparative Analysis of Fuzzy Set Defuzzification Methods in the Context of Ecological Risk Assessment

    Directory of Open Access Journals (Sweden)

    Užga-Rebrovs Oļegs

    2017-12-01

    Full Text Available Fuzzy inference systems are widely used in various areas of human activity. Their most widespread use lies in the field of fuzzy control of technical devices of different kind. Another direction of using fuzzy inference systems is modelling and assessment of different kind of risks under insufficient or missing objective initial data. Fuzzy inference is concluded by the procedure of defuzzification of the resulting fuzzy sets. A large number of techniques for implementing the defuzzification procedure are available nowadays. The paper presents a comparative analysis of some widespread methods of fuzzy set defuzzification, and proposes the most appropriate methods in the context of ecological risk assessment.

  3. Introducing a Method for Social-ecological Assessment of Small Urban Parks

    Directory of Open Access Journals (Sweden)

    Zanariah Jasman

    2016-06-01

    Full Text Available Small parks in cities are important to support overall urban biodiversity and ecological network. The aim of this paper is to introduce a method of identifying and assessing the ecological characteristics and anthropogenic factors of small urban parks. We developed a framework that combined structured observation and field measurement. The method suggests an integrative assessment that is practical and understandable to the park planners and managers to enhance small parks to support overall urban biodiversity and ecosystem services. High biodiversity can provide opportunities for humans to experience nature and wildlife in cities, thus contributing to the quality of life of urban dwellers.

  4. A Method for Eddy Current Field Measurement in Permanent Magnet Magnetic Resonance Imaging Systems

    Directory of Open Access Journals (Sweden)

    SONG Rui

    2018-03-01

    Full Text Available Magnetic resonance imaging (MRI is a widely used medical imaging technique. In MRI system, gradient magnetic fields are used to code spatial information. However, the fast-switching electric currents in the gradients coils used to generate gradient fields also induce vortex electric field, often referred as eddy current, in the surrounding metal conductors. In this paper, a method for eddy current field measurement was proposed. Based on the Faraday law of electromagnetic induction, an eddy current field measuring device was designed. Combining hardware acquisition and software processing, the eddy current field was obtained by subtracting the ideal gradient field from the magnetic field measured experimentally, whose waveform could be displayed in real time. The proposed method was verified by experimental results.

  5. The study of combining Latin Hypercube Sampling method and LU decomposition method (LULHS method) for constructing spatial random field

    Science.gov (United States)

    WANG, P. T.

    2015-12-01

    Groundwater modeling requires to assign hydrogeological properties to every numerical grid. Due to the lack of detailed information and the inherent spatial heterogeneity, geological properties can be treated as random variables. Hydrogeological property is assumed to be a multivariate distribution with spatial correlations. By sampling random numbers from a given statistical distribution and assigning a value to each grid, a random field for modeling can be completed. Therefore, statistics sampling plays an important role in the efficiency of modeling procedure. Latin Hypercube Sampling (LHS) is a stratified random sampling procedure that provides an efficient way to sample variables from their multivariate distributions. This study combines the the stratified random procedure from LHS and the simulation by using LU decomposition to form LULHS. Both conditional and unconditional simulations of LULHS were develpoed. The simulation efficiency and spatial correlation of LULHS are compared to the other three different simulation methods. The results show that for the conditional simulation and unconditional simulation, LULHS method is more efficient in terms of computational effort. Less realizations are required to achieve the required statistical accuracy and spatial correlation.

  6. Absorbed dose determination in photon fields using the tandem method

    International Nuclear Information System (INIS)

    Marques Pachas, J.F.

    1999-01-01

    The purpose of this work is to develop an alternative method to determine the absorbed dose and effective energy of photons with unknown spectral distributions. It includes a 'tandem' system that consists of two thermoluminescent dosemeters with different energetic dependence. LiF: Mg, Ti, CaF 2 : Dy thermoluminescent dosemeters and a Harshaw 3500 reading system are employed. Dosemeters are characterized with 90 Sr- 90 Y, calibrated with the energy of 60 Co and irradiated with seven different qualities of x-ray beams, suggested by ANSI No. 13 and ISO 4037. The answers of each type of dosemeter are adjusted to a function that depends on the effective energy of photons. The adjustment is carried out by means of the Rosenbrock minimization algorithm. The mathematical model used for this function includes five parameters and has a gauss and a straight line. Results show that the analytical functions reproduce the experimental data of the answers, with a margin of error of less than 5%. The reason of the answers of the CaF 2 : Dy and LiF: Mg, Ti, according to the energy of the radiation, allows us to establish the effective energy of photons and the absorbed dose, with a margin of error of less than 10% and 20% respectively

  7. Detection of concrete dam leakage using an integrated geophysical technique based on flow-field fitting method

    Science.gov (United States)

    Dai, Qianwei; Lin, Fangpeng; Wang, Xiaoping; Feng, Deshan; Bayless, Richard C.

    2017-05-01

    An integrated geophysical investigation was performed at S dam located at Dadu basin in China to assess the condition of the dam curtain. The key methodology of the integrated technique used was flow-field fitting method, which allowed identification of the hydraulic connections between the dam foundation and surface water sources (upstream and downstream), and location of the anomalous leakage outlets in the dam foundation. Limitations of the flow-field fitting method were complemented with resistivity logging to identify the internal erosion which had not yet developed into seepage pathways. The results of the flow-field fitting method and resistivity logging were consistent when compared with data provided by seismic tomography, borehole television, water injection test, and rock quality designation.

  8. Assessment of active methods for removal of LEO debris

    Science.gov (United States)

    Hakima, Houman; Emami, M. Reza

    2018-03-01

    This paper investigates the applicability of five active methods for removal of large low Earth orbit debris. The removal methods, namely net, laser, electrodynamic tether, ion beam shepherd, and robotic arm, are selected based on a set of high-level space mission constraints. Mission level criteria are then utilized to assess the performance of each redirection method in light of the results obtained from a Monte Carlo simulation. The simulation provides an insight into the removal time, performance robustness, and propellant mass criteria for the targeted debris range. The remaining attributes are quantified based on the models provided in the literature, which take into account several important parameters pertaining to each removal method. The means of assigning attributes to each assessment criterion is discussed in detail. A systematic comparison is performed using two different assessment schemes: Analytical Hierarchy Process and utility-based approach. A third assessment technique, namely the potential-loss analysis, is utilized to highlight the effect of risks in each removal methods.

  9. Full-reference quality assessment of stereoscopic images by learning binocular receptive field properties.

    Science.gov (United States)

    Shao, Feng; Li, Kemeng; Lin, Weisi; Jiang, Gangyi; Yu, Mei; Dai, Qionghai

    2015-10-01

    Quality assessment of 3D images encounters more challenges than its 2D counterparts. Directly applying 2D image quality metrics is not the solution. In this paper, we propose a new full-reference quality assessment for stereoscopic images by learning binocular receptive field properties to be more in line with human visual perception. To be more specific, in the training phase, we learn a multiscale dictionary from the training database, so that the latent structure of images can be represented as a set of basis vectors. In the quality estimation phase, we compute sparse feature similarity index based on the estimated sparse coefficient vectors by considering their phase difference and amplitude difference, and compute global luminance similarity index by considering luminance changes. The final quality score is obtained by incorporating binocular combination based on sparse energy and sparse complexity. Experimental results on five public 3D image quality assessment databases demonstrate that in comparison with the most related existing methods, the devised algorithm achieves high consistency with subjective assessment.

  10. Systematic evaluation of observational methods assessing biomechanical exposures at work

    DEFF Research Database (Denmark)

    Takala, Esa-Pekka; Irmeli, Pehkonen; Forsman, Mikael

    2009-01-01

    by sorting the methods according to the several items evaluated.   Numerous methods have been developed to assess physical workload (biomechanical exposures) in order to identify hazards leading to musculoskeletal disorders, to monitor the effects of ergonomic changes, and for research. No indvidual method...... between observers Potential users NIOSH Lifting Eq. NA X - O, R Arbouw M - - O ACGIH Lifting TLV M - - O MAC - - M O, W(?) ManTRA - - - O, R(?),W(?) NZ Code for MH - - - O, W(?) Washington state ergonomic rule M X M O, W(?) BackEST ML - M R   Correspondence with valid reference: HM = High to moderate, L......), and Washington state model. MAC (UK), ManTRA (Australia), and New Zealand code are widely used for the assessment of risks in MMH but we did not found formal studies on validity of these methods. The inter-observer repeatability of MAC and the Washington state model has been found to be moderate. Back...

  11. The full size validation of remanent life assessment methods

    International Nuclear Information System (INIS)

    Hepworth, J.K.; Williams, J.A.

    1988-03-01

    A range of possible life assessment techniques for the remanent life appraisal of creeping structures is available in the published literature. However, due to the safety implications, the true conservatism of such methods cannot be assessed on operating plant. Consequently, the CEGB set up a four vessel programme in the Pressure Vessel Test Facility at the Marchwood Engineering Laboratories of the CEGB to underwrite and quantify the accuracy of these methods. The application of two non-destructive methods, namely strain monitoring and hardness measurement, to the data generated during about 12,000 hours of testing is examined. The current state of development of these methods is reviewed. Finally, the future CEGB programme relating to these vessels is discussed. (author)

  12. Indoor air - assessment: Methods of analysis for environmental carcinogens

    International Nuclear Information System (INIS)

    Peterson, M.R.; Naugle, D.F.; Berry, M.A.

    1990-06-01

    The monograph describes, in a general way, published sampling procedures and analytical approaches for known and suspected carcinogens. The primary focus is upon carcinogens found in indoor air, although the methods described are applicable to other media or environments. In cases where there are no published methods for a particular pollutant in indoor air, methods developed for the workplace and for ambient air are included since they should be adaptable to indoor air. Known and suspected carcinogens have been grouped into six categories for the purposes of this and related work. The categories are radon, asbestos, organic compounds, inorganic species, particles, and non-ionizing radiation. Some methods of assessing exposure that are not specific to any particular pollutant category are covered in a separate section. The report is the fifth in a series of EPA/Environmental Criteria and Assessment Office Monographs

  13. Electromagnetic fields: risk assessment and occupational diseases in Italy

    Energy Technology Data Exchange (ETDEWEB)

    Filosa, L.; Frusteri, L. [Risk Assessment and Prevention, Technical Advisory Dept., Italian Workers Compensation Authority, Rome (Italy)

    2006-07-01

    Every year about 8000 occupational diseases are accepted in Italy by I.N.A.I.L., the Italian Workers' Compensation Authority. The occupational diseases are caused by different agents (chemical, biological, physical) but only a very little percentage resulted to be caused by non ionizing radiations. In this paper the Authors report an analysis of occupational diseases caused by non ionising radiations denounced to I.N.A.I.L. and compensated. It is discussed the Italian situation in light of the controversial studies related to the link between exposure and health effects. Because of the uncertainty about an E.M.F. - health link, the main effort is to determine the probability and seriousness of E.M.F. hazard and to realize an accurate risk assessment at workplace, which is one of the main objectives pursued by I.N.A.I.L. Technical Advisory Department for Risk Assessment and Prevention. Moreover, in this paper it is also reported the state of advancement of Italian legislation on health protection against non ionizing radiations at workplace in view of the new European Directive (2004/40/C.E.). (authors)

  14. EME assessments using telstra's mobile base station field intensity plotter

    International Nuclear Information System (INIS)

    Wood, M.; Hurren, S.; Vinnal, E.; Armstrong, M.

    2001-01-01

    Public interest in the potential health issues arising from mobile phone base stations has highlighted the importance of having accessible and easy to understand information on electromagnetic energy (EME) emission levels. A range of groups including residents, community groups, businesses, schools, site owners and local governments are often interested in knowing what EME levels a particular base station is capable of producing and how these compare to safety standards regulated by the Australian Communications Authority (ACA). Performing the complex mathematical calculations to predict these levels requires significant expertise, is time consuming and relatively costly. A new software tool, born out of Telstra's EME Research and Development Program, is set to revolutionise EME assessments by facilitating the provision of this information in a more timely, standardised and cost effective manner. Telstra has taken the decision to commercialise the software, which is a world first, because of expressions of interest from other carriers, EME assessment specialists, government agencies and regulatory organisations both in Australia and overseas. Significantly, the software should improve the flow of easy to understand and accurate information on emission levels from base stations. Copyright (2001) Australasian Radiation Protection Society Inc

  15. Electromagnetic fields: risk assessment and occupational diseases in Italy

    International Nuclear Information System (INIS)

    Filosa, L.; Frusteri, L.

    2006-01-01

    Every year about 8000 occupational diseases are accepted in Italy by I.N.A.I.L., the Italian Workers' Compensation Authority. The occupational diseases are caused by different agents (chemical, biological, physical) but only a very little percentage resulted to be caused by non ionizing radiations. In this paper the Authors report an analysis of occupational diseases caused by non ionising radiations denounced to I.N.A.I.L. and compensated. It is discussed the Italian situation in light of the controversial studies related to the link between exposure and health effects. Because of the uncertainty about an E.M.F. - health link, the main effort is to determine the probability and seriousness of E.M.F. hazard and to realize an accurate risk assessment at workplace, which is one of the main objectives pursued by I.N.A.I.L. Technical Advisory Department for Risk Assessment and Prevention. Moreover, in this paper it is also reported the state of advancement of Italian legislation on health protection against non ionizing radiations at workplace in view of the new European Directive (2004/40/C.E.). (authors)

  16. ALTERNATIVE FIELD METHODS TO TREAT MERCURY IN SOIL

    Energy Technology Data Exchange (ETDEWEB)

    Ernie F. Stine

    2002-08-14

    The Department of Energy (DOE) currently has mercury (Hg) contaminated materials and soils at the various sites. Figure 1-1 (from http://www.ct.ornl.gov/stcg.hg/) shows the estimated distribution of mercury contaminated waste at the various DOE sites. Oak Ridge and Idaho sites have the largest deposits of contaminated materials. The majorities of these contaminated materials are soils, sludges, debris, and waste waters. This project concerns treatment of mercury contaminated soils. The technology is applicable to many DOE sites, in-particular, the Y-12 National Security Complex in Oak Ridge Tennessee and Idaho National Engineering and Environmental Laboratory (INEEL). These sites have the majority of the soils and sediments contaminated with mercury. The soils may also be contaminated with other hazardous metals and radionuclides. At the Y12 plant, the baseline treatment method for mercury contaminated soil is low temperature thermal desorption (LTTD), followed by on-site landfill disposal. LTTD is relatively expensive (estimated cost of treatment which exclude disposal cost for the collect mercury is greater than $740/per cubic yard [cy] at Y-12), does not treat any of the metal or radionuclides. DOE is seeking a less costly alternative to the baseline technology. As described in the solicitation (DE-RA-01NT41030), this project initially focused on evaluating cost-effective in-situ alternatives to stabilize or remove the mercury (Hg) contamination from high-clay content soil. It was believed that ex-situ treatment of soil contaminated with significant quantities of free-liquid mercury might pose challenges during excavation and handling. Such challenges may include controlling potential mercury vapors and containing liquid mercury beads. As described below, the focus of this project was expanded to include consideration of ex-situ treatment after award of the contract to International Technology Corporation (IT). After award of the contract, IT became part of Shaw

  17. ALTERNATIVE FIELD METHODS TO TREAT MERCURY IN SOIL

    International Nuclear Information System (INIS)

    Stine, Ernie F.

    2002-01-01

    The Department of Energy (DOE) currently has mercury (Hg) contaminated materials and soils at the various sites. Figure 1-1 (from http://www.ct.ornl.gov/stcg.hg/) shows the estimated distribution of mercury contaminated waste at the various DOE sites. Oak Ridge and Idaho sites have the largest deposits of contaminated materials. The majorities of these contaminated materials are soils, sludges, debris, and waste waters. This project concerns treatment of mercury contaminated soils. The technology is applicable to many DOE sites, in-particular, the Y-12 National Security Complex in Oak Ridge Tennessee and Idaho National Engineering and Environmental Laboratory (INEEL). These sites have the majority of the soils and sediments contaminated with mercury. The soils may also be contaminated with other hazardous metals and radionuclides. At the Y12 plant, the baseline treatment method for mercury contaminated soil is low temperature thermal desorption (LTTD), followed by on-site landfill disposal. LTTD is relatively expensive (estimated cost of treatment which exclude disposal cost for the collect mercury is greater than $740/per cubic yard [cy] at Y-12), does not treat any of the metal or radionuclides. DOE is seeking a less costly alternative to the baseline technology. As described in the solicitation (DE-RA-01NT41030), this project initially focused on evaluating cost-effective in-situ alternatives to stabilize or remove the mercury (Hg) contamination from high-clay content soil. It was believed that ex-situ treatment of soil contaminated with significant quantities of free-liquid mercury might pose challenges during excavation and handling. Such challenges may include controlling potential mercury vapors and containing liquid mercury beads. As described below, the focus of this project was expanded to include consideration of ex-situ treatment after award of the contract to International Technology Corporation (IT). After award of the contract, IT became part of Shaw

  18. A new framework for interactive quality assessment with application to light field coding

    Science.gov (United States)

    Viola, Irene; Ebrahimi, Touradj

    2017-09-01

    In recent years, light field has experienced a surge of popularity, mainly due to the recent advances in acquisition and rendering technologies that have made it more accessible to the public. Thanks to image-based rendering techniques, light field contents can be rendered in real time on common 2D screens, allowing virtual navigation through the captured scenes in an interactive fashion. However, this richer representation of the scene poses the problem of reliable quality assessments for light field contents. In particular, while subjective methodologies that enable interaction have already been proposed, no work has been done on assessing how users interact with light field contents. In this paper, we propose a new framework to subjectively assess the quality of light field contents in an interactive manner and simultaneously track users behaviour. The framework is successfully used to perform subjective assessment of two coding solutions. Moreover, statistical analysis performed on the results shows interesting correlation between subjective scores and average interaction time.

  19. Method to map individual electromagnetic field components inside a photonic crystal

    NARCIS (Netherlands)

    Denis, T.; Reijnders, B.; Lee, J.H.H.; van der Slot, Petrus J.M.; Vos, Willem L.; Boller, Klaus J.

    2012-01-01

    We present a method to map the absolute electromagnetic field strength inside photonic crystals. We apply the method to map the dominant electric field component Ez of a two-dimensional photonic crystal slab at microwave frequencies. The slab is placed between two mirrors to select Bloch standing

  20. Risk and dose assessment methods in gamma knife QA

    International Nuclear Information System (INIS)

    Banks, W.W.; Jones, E.D.; Rathbun, P.

    1992-10-01

    Traditional methods used in assessing risk in nuclear power plants may be inappropriate to use in assessing medical radiation risks. The typical philosophy used in assessing nuclear reactor risks is machine dominated with only secondary attention paid to the human component, and only after critical machine failure events have been identified. In assessing the risk of a misadministrative radiation dose to patients, the primary source of failures seems to stem overwhelmingly, from the actions of people and only secondarily from machine mode failures. In essence, certain medical misadministrations are dominated by human events not machine failures. Radiological medical devices such as the Leksell Gamma Knife are very simple in design, have few moving parts, and are relatively free from the risks of wear when compared with a nuclear power plant. Since there are major technical differences between a gamma knife and a nuclear power plant, one must select a particular risk assessment method which is sensitive to these system differences and tailored to the unique medical aspects of the phenomena under study. These differences also generate major shifts in the philosophy and assumptions which drive the risk assessment (Machine-centered vs Person-centered) method. We were prompted by these basic differences to develop a person-centered approach to risk assessment which would reflect these basic philosophical and technological differences, have the necessary resolution in its metrics, and be highly reliable (repeatable). The risk approach chosen by the Livermore investigative team has been called the ''Relative Risk Profile Method'' and has been described in detail by Banks and Paramore, (1983)

  1. Rodent sperm analysis in field-based ecological risk assessment: pilot study at Ravenna army ammunition plant, Ravenna, Ohio

    International Nuclear Information System (INIS)

    Tannenbaum, L.V.; Bazar, M.; Hawkins, M.S.; Cornaby, B.W.; Ferguson, E.A.; Chantelle Carroll, L.; Ryan, P.F.

    2003-01-01

    Rodent sperm analysis is a visable method for use in field studies of risk at contaminated sites. - Ecological risk assessment (ERA) guidance recommends that field-truthing efforts proceed when modeled hazard quotients (HQs) suggest that toxicological effects are occurring to site receptors. To date, no field methods have been proposed by the regulatory community that can lead to definitive determinations of acceptable or unacceptable risk for birds and mammals, the two terrestrial classes of receptors that are commonly assessed using the HQ method. This paper describes rodent sperm analysis (RSA) as a viable method to be applied in the field at sites with historical contamination. RSA is capable of detecting biological differences that bear on reproduction, a highly regarded toxicological endpoint of concern in USEPA Superfund-type ERAs. The results of RSA's first application at a study site are reported and discussed. The paper also provides the rationale for RSA's efficacy in the context of Superfund and other environmental cleanup programs, where limited time and money are available to determine and evaluate the field condition

  2. Development of fire risk assessment method caused by earthquake

    International Nuclear Information System (INIS)

    Mitomo, Nobuo; Matsukura, Hiroshi; Matsuoka, Takeshi; Suzuki, Kazutaka

    2000-01-01

    The purpose of this research is to establish the assessment method of the risk of the multiple fires caused by earthquake, in the framework of PSA. In order to establish this method, we have settled four tasks and started a five years research project in 1999 for five years. These results will be useful for not only nuclear power plants but also chemical plants, traffic systems etc. (author)

  3. Challenges of assessing fire and burn severity using field measures, remote sensing and modelling

    Science.gov (United States)

    Penelope Morgan; Robert E. Keane; Gregory K. Dillon; Theresa B. Jain; Andrew T. Hudak; Eva C. Karau; Pamela G. Sikkink; Zachery A. Holden; Eva K. Strand

    2014-01-01

    Comprehensive assessment of ecological change after fires have burned forests and rangelands is important if we are to understand, predict and measure fire effects. We highlight the challenges in effective assessment of fire and burn severity in the field and using both remote sensing and simulation models. We draw on diverse recent research for guidance on assessing...

  4. 76 FR 81467 - Availability of an Environmental Assessment for Field Testing Swine Influenza Vaccine, RNA

    Science.gov (United States)

    2011-12-28

    ...] Availability of an Environmental Assessment for Field Testing Swine Influenza Vaccine, RNA AGENCY: Animal and... Vaccine, RNA. The environmental assessment, which is based on a risk analysis prepared to assess the risks...: Send your comment to Docket No. APHIS-2011-0114, Regulatory Analysis and Development, PPD, APHIS...

  5. Random field assessment of nanoscopic inhomogeneity of bone

    OpenAIRE

    Dong, X. Neil; Luo, Qing; Sparkman, Daniel M.; Millwater, Harry R.; Wang, Xiaodu

    2010-01-01

    Bone quality is significantly correlated with the inhomogeneous distribution of material and ultrastructural properties (e.g., modulus and mineralization) of the tissue. Current techniques for quantifying inhomogeneity consist of descriptive statistics such as mean, standard deviation and coefficient of variation. However, these parameters do not describe the spatial variations of bone properties. The objective of this study was to develop a novel statistical method to characterize and quanti...

  6. Representativeness of environmental impact assessment methods regarding Life Cycle Inventories.

    Science.gov (United States)

    Esnouf, Antoine; Latrille, Éric; Steyer, Jean-Philippe; Helias, Arnaud

    2018-04-15

    Life Cycle Assessment (LCA) characterises all the exchanges between human driven activities and the environment, thus representing a powerful approach for tackling the environmental impact of a production system. However, LCA practitioners must still choose the appropriate Life Cycle Impact Assessment (LCIA) method to use and are expected to justify this choice: impacts should be relevant facing the concerns of the study and misrepresentations should be avoided. This work aids practitioners in evaluating the adequacy between the assessed environmental issues and studied production system. Based on a geometrical standpoint of LCA framework, Life Cycle Inventories (LCIs) and LCIA methods were localized in the vector space spanned by elementary flows. A proximity measurement, the Representativeness Index (RI), is proposed to explore the relationship between those datasets (LCIs and LCIA methods) through an angular distance. RIs highlight LCIA methods that measure issues for which the LCI can be particularly harmful. A high RI indicates a close proximity between a LCI and a LCIA method, and highlights a better representation of the elementary flows by the LCIA method. To illustrate the benefits of the proposed approach, representativeness of LCIA methods regarding four electricity mix production LCIs from the ecoinvent database are presented. RIs for 18 LCIA methods (accounting for a total of 232 impact categories) were calculated on these LCIs and the relevance of the methods are discussed. RIs prove to be a criterion for distinguishing the different LCIA methods and could thus be employed by practitioners for deeper interpretations of LCIA results. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Near-Field Hydrology Data Package for the Immobilized Low-Activity Waste 2001 Performance Assessment

    International Nuclear Information System (INIS)

    PD Meyer; RJ Serne

    1999-01-01

    Lockheed Martin Hanford Company (LMHC) is designing and assessing the performance of disposal facilities to receive radioactive wastes that are currently stored in single- and double-shell tanks at the Hanford Site. The preferred method for disposing of the portion that is classified as immobilized low-activity waste (ILAW) is to vitrify the waste and place the product in new-surface, shallow land burial facilities. The LMHC project to assess the performance of these disposal facilities is the Hanford ILAW Performance Assessment (PA) Activity. The goal of this project is to provide a reasonable expectation that the disposal of the waste is protective of the general public, groundwater resources, air resources, surface water resources, and inadvertent intruders. Achieving this goal will require prediction of contaminant migration from the facilities. This migration is expected to occur primarily via the movement of water through the facilities and the consequent transport of dissolved contaminants in the pore water of the vadose zone. Pacific Northwest National Laboratory (PNNL) assists LMHC in its performance assessment activities. One of PNNL's tasks is to provide estimates of the physical, hydraulic, and transport properties of the materials comprising the disposal facilities and the disturbed region around them. These materials are referred to as the near-field materials. Their properties are expressed as parameters of constitutive models used in simulations of subsurface flow and transport. In addition to the best-estimate parameter values, information on uncertainty in the parameter values and estimates of the changes in parameter values over time are required to complete the PA. These parameter estimates and information are contained in this report, the Near-Field Hydrology Data Package

  8. Context-Based Assessment: Creating Opportunities for Resonance between Classroom Fields and Societal Fields

    Science.gov (United States)

    Bellocchi, Alberto; King, Donna T.; Ritchie, Stephen M.

    2016-01-01

    There is on-going international interest in the relationships between assessment instruments, students' understanding of science concepts and context-based curriculum approaches. This study extends earlier research showing that students can develop connections between contexts and concepts--called "fluid transitions"--when studying…

  9. Significance and challenges of stereoselectivity assessing methods in drug metabolism

    Directory of Open Access Journals (Sweden)

    Zhuowei Shen

    2016-02-01

    Full Text Available Stereoselectivity in drug metabolism can not only influence the pharmacological activities, tolerability, safety, and bioavailability of drugs directly, but also cause different kinds of drug–drug interactions. Thus, assessing stereoselectivity in drug metabolism is of great significance for pharmaceutical research and development (R&D and rational use in clinic. Although there are various methods available for assessing stereoselectivity in drug metabolism, many of them have shortcomings. The indirect method of chromatographic methods can only be applicable to specific samples with functional groups to be derivatized or form complex with a chiral selector, while the direct method achieved by chiral stationary phases (CSPs is expensive. As a detector of chromatographic methods, mass spectrometry (MS is highly sensitive and specific, whereas the matrix interference is still a challenge to overcome. In addition, the use of nuclear magnetic resonance (NMR and immunoassay in chiral analysis are worth noting. This review presents several typical examples of drug stereoselective metabolism and provides a literature-based evaluation on current chiral analytical techniques to show the significance and challenges of stereoselectivity assessing methods in drug metabolism.

  10. A field assessment of the value of steady shape hydraulic tomography for characterization of aquifer heterogeneities

    Science.gov (United States)

    Bohling, Geoffrey C.; Butler, James J.; Zhan, Xiaoyong; Knoll, Michael D.

    2007-01-01

    Hydraulic tomography is a promising approach for obtaining information on variations in hydraulic conductivity on the scale of relevance for contaminant transport investigations. This approach involves performing a series of pumping tests in a format similar to tomography. We present a field‐scale assessment of hydraulic tomography in a porous aquifer, with an emphasis on the steady shape analysis methodology. The hydraulic conductivity (K) estimates from steady shape and transient analyses of the tomographic data compare well with those from a tracer test and direct‐push permeameter tests, providing a field validation of the method. Zonations based on equal‐thickness layers and cross‐hole radar surveys are used to regularize the inverse problem. The results indicate that the radar surveys provide some useful information regarding the geometry of the K field. The steady shape analysis provides results similar to the transient analysis at a fraction of the computational burden. This study clearly demonstrates the advantages of hydraulic tomography over conventional pumping tests, which provide only large‐scale averages, and small‐scale hydraulic tests (e.g., slug tests), which cannot assess strata connectivity and may fail to sample the most important pathways or barriers to flow.

  11. Assessment of a dynamic reference material for calibration of full-field measurement systems

    Science.gov (United States)

    Hack, Erwin; Feligiotti, Mara; Davighi, Andrea; Whelan, Maurice; Wang, Weizhuo V.; Patterson, Eann A.

    2012-10-01

    For holography and speckle interferometry the calibration of the sensitivity is a must, because illumination and observation directions vary across the field of view. A numerical estimate or a static calibration using rigid body motions is standard, and reference materials exist for static strain calibration. Recently, reference materials for the dynamic calibration of optical instruments of displacement and strain measurement were designed and prototypes were manufactured in the European FP7 project ADVISE. We review the properties of the reference material and the concept of traceability for the field of displacement values by using a calibrated single point transducer. The mode shape is assessed using out-of-plane DSPI, Finite Element Analysis as well as analytic solutions of the plate vibration. We present measurements using stroboscopic DSPI on the reference material under acoustic excitation and compare the measured mode shapes to the ones predicted by FE analysis. We apply different comparison methodologies based on point-by-point deviations and on decomposition of the mode shapes into a set of orthogonal basis functions. The latter method is well suited to assess stability and reproducibility of a mode shape. Finally, the deviations are used to estimate the reference material uncertainty which is an essential parameter for determining the calibration uncertainty. Uncertainty contributions of the DSPI set-up are taken into account. To conclude, the application area and limitations of the reference material are discussed.

  12. Assessment of a portable lactate meter for field use in the white rhinoceros (Ceratotherium simum).

    Science.gov (United States)

    Cole, Georgina C; Tordiffe, Adrian S W; Steenkamp, Gerhard

    2017-11-10

    Blood lactate is a predictor of mortality in critically ill humans and animals. Handheld lactate meters have the potential to be used in the field to evaluate the condition of severely injured rhinoceroses but have not been compared with laboratory-based methods. Agreement between a handheld lactate meter and a laboratory method was assessed, as was the stability of rhino blood lactate in the anticoagulant sodium fluoride/potassium oxalate (fluoride/oxalate). Blood samples were obtained from 53 white rhinos that had been immobilised for management reasons. Lactate was measured by means of a handheld meter using whole blood in heparin (WBHEP), whole blood in fluoride/oxalate (WBFO) and fluoride/oxalate plasma (PFO). Results were recorded in both blood (BL) and plasma (PL) modes and compared to an established laboratory method for measuring plasma lactate. To assess the stability of lactate over time, blood lactate in fluoride/oxalate was measured on the handheld meter at intervals for up to 91 h. Agreement was best using WBFO in PL mode, with small bias (-0.16), tight 95% limits of agreement (LOA) (-1.46, 1.14) and a Pc (95% CI) of 0.97 (0.92, 0.99). The agreement was improved for all sample types when using the PL mode compared to the blood lactate (BL) mode. Blood lactate was stable in fluoride/oxalate for 91 h, with a mean change from baseline of 0.15 (-0.178, 0.478) mmol/L (mean, 95% CI). The handheld meter was found to be suitable for field use in white rhinos but provided more reliable results with the device in PL mode. Furthermore, rhino blood lactate was found to be stable in fluoride/oxalate for as long as 3 days.

  13. An Entropy-Based Propagation Speed Estimation Method for Near-Field Subsurface Radar Imaging

    Directory of Open Access Journals (Sweden)

    Pistorius Stephen

    2010-01-01

    Full Text Available During the last forty years, Subsurface Radar (SR has been used in an increasing number of noninvasive/nondestructive imaging applications, ranging from landmine detection to breast imaging. To properly assess the dimensions and locations of the targets within the scan area, SR data sets have to be reconstructed. This process usually requires the knowledge of the propagation speed in the medium, which is usually obtained by performing an offline measurement from a representative sample of the materials that form the scan region. Nevertheless, in some novel near-field SR scenarios, such as Microwave Wood Inspection (MWI and Breast Microwave Radar (BMR, the extraction of a representative sample is not an option due to the noninvasive requirements of the application. A novel technique to determine the propagation speed of the medium based on the use of an information theory metric is proposed in this paper. The proposed method uses the Shannon entropy of the reconstructed images as the focal quality metric to generate an estimate of the propagation speed in a given scan region. The performance of the proposed algorithm was assessed using data sets collected from experimental setups that mimic the dielectric contrast found in BMI and MWI scenarios. The proposed method yielded accurate results and exhibited an execution time in the order of seconds.

  14. An Entropy-Based Propagation Speed Estimation Method for Near-Field Subsurface Radar Imaging

    Science.gov (United States)

    Flores-Tapia, Daniel; Pistorius, Stephen

    2010-12-01

    During the last forty years, Subsurface Radar (SR) has been used in an increasing number of noninvasive/nondestructive imaging applications, ranging from landmine detection to breast imaging. To properly assess the dimensions and locations of the targets within the scan area, SR data sets have to be reconstructed. This process usually requires the knowledge of the propagation speed in the medium, which is usually obtained by performing an offline measurement from a representative sample of the materials that form the scan region. Nevertheless, in some novel near-field SR scenarios, such as Microwave Wood Inspection (MWI) and Breast Microwave Radar (BMR), the extraction of a representative sample is not an option due to the noninvasive requirements of the application. A novel technique to determine the propagation speed of the medium based on the use of an information theory metric is proposed in this paper. The proposed method uses the Shannon entropy of the reconstructed images as the focal quality metric to generate an estimate of the propagation speed in a given scan region. The performance of the proposed algorithm was assessed using data sets collected from experimental setups that mimic the dielectric contrast found in BMI and MWI scenarios. The proposed method yielded accurate results and exhibited an execution time in the order of seconds.

  15. Greenhouse and field assessment of rhizobacteria to control guava decline

    Directory of Open Access Journals (Sweden)

    Alexandre Macedo Almeida

    2011-01-01

    Full Text Available In an effort to devise a biological strategy to control guava decline, 120 rhizobacteria isolates were obtained from symptomless guava trees located in Meloidogyne enterolobii-infested orchards. Of those isolates, 44 were assessed for their potential to reduce nematode's reproduction: for each isolate, six guava stem cuttings were embedded for eight hours with bacterial suspension and transplanted. Upon development of the roots, the plants were inoculated with 2000 nematode eggs and allowed to grow for four months under greenhouse. Seedlings embedded with water, inoculated or not with the nematode, served as controls. All treatments were equivalent in the five variables that assessed plant development. Several rhizobacteria reduced (p<0.05 the final nematode population (Fp, Fp/gram of root and reproduction factor, although not to satisfactory levels. Subsequently, a two-year experiment was set up in a guava orchard affected by guava decline, in which three of the most effective rhizobacterial isolates were compared with the biological products Nemat® and Nemaplus® for their ability to reduce variables related to nematode parasitism and increase guava productivity. Seven bimonthly applications of these treatments under the tree canopy were unable to reduce nematode parasitism and increase productivity. The decline and death of some plants forced the experiment to be stopped after the first harvest. In conclusion, rhizobacteria applications seem unable to reduce the parasitism of M. enterolobii on guava plants, and even less to reduce the extensive root decay or alleviate the physiological stress suffered by trees affected by guava decline.

  16. A quantitative method for assessing resilience of interdependent infrastructures

    International Nuclear Information System (INIS)

    Nan, Cen; Sansavini, Giovanni

    2017-01-01

    The importance of understanding system resilience and identifying ways to enhance it, especially for interdependent infrastructures our daily life depends on, has been recognized not only by academics, but also by the corporate and public sectors. During recent years, several methods and frameworks have been proposed and developed to explore applicable techniques to assess and analyze system resilience in a comprehensive way. However, they are often tailored to specific disruptive hazards/events, or fail to properly include all the phases such as absorption, adaptation, and recovery. In this paper, a quantitative method for the assessment of the system resilience is proposed. The method consists of two components: an integrated metric for system resilience quantification and a hybrid modeling approach for representing the failure behavior of infrastructure systems. The feasibility and applicability of the proposed method are tested using an electric power supply system as the exemplary infrastructure. Simulation results highlight that the method proves effective in designing, engineering and improving the resilience of infrastructures. Finally, system resilience is proposed as a proxy to quantify the coupling strength between interdependent infrastructures. - Highlights: • A method for quantifying resilience of interdependent infrastructures is proposed. • It combines multi-layer hybrid modeling and a time-dependent resilience metric. • The feasibility of the proposed method is tested on the electric power supply system. • The method provides insights to decision-makers for strengthening system resilience. • Resilience capabilities can be used to engineer interdependencies between subsystems.

  17. An Identification Key for Selecting Methods for Sustainability Assessments

    Directory of Open Access Journals (Sweden)

    Michiel C. Zijp

    2015-03-01

    Full Text Available Sustainability assessments can play an important role in decision making. This role starts with selecting appropriate methods for a given situation. We observed that scientists, consultants, and decision-makers often do not systematically perform a problem analyses that guides the choice of the method, partly related to a lack of systematic, though sufficiently versatile approaches to do so. Therefore, we developed and propose a new step towards method selection on the basis of question articulation: the Sustainability Assessment Identification Key. The identification key was designed to lead its user through all important choices needed for comprehensive question articulation. Subsequently, methods that fit the resulting specific questions are suggested by the key. The key consists of five domains, of which three determine method selection and two the design or use of the method. Each domain consists of four or more criteria that need specification. For example in the domain “system boundaries”, amongst others, the spatial and temporal scales are specified. The key was tested (retrospectively on a set of thirty case studies. Using the key appeared to contribute to improved: (i transparency in the link between the question and method selection; (ii consistency between questions asked and answers provided; and (iii internal consistency in methodological design. There is latitude to develop the current initial key further, not only for selecting methods pertinent to a problem definition, but also as a principle for associated opportunities such as stakeholder identification.

  18. Electromagnetic Field Assessment as a Smart City Service: The SmartSantander Use-Case.

    Science.gov (United States)

    Diez, Luis; Agüero, Ramón; Muñoz, Luis

    2017-05-31

    Despite the increasing presence of wireless communications in everyday life, there exist some voices raising concerns about their adverse effects. One particularly relevant example is the potential impact of the electromagnetic field they induce on the population's health. Traditionally, very specialized methods and devices (dosimetry) have been used to assess the strength of the E-field, with the main objective of checking whether it respects the corresponding regulations. In this paper, we propose a complete novel approach, which exploits the functionality leveraged by a smart city platform. We deploy a number of measuring probes, integrated as sensing devices, to carry out a characterization embracing large areas, as well as long periods of time. This unique platform has been active for more than one year, generating a vast amount of information. We process such information, and the obtained results validate the whole methodology. In addition, we discuss the variation of the E-field caused by cellular networks, considering additional information, such as usage statistics. Finally, we establish the exposure that can be attributed to the base stations within the scenario under analysis.

  19. Electromagnetic Field Assessment as a Smart City Service: The SmartSantander Use-Case

    Directory of Open Access Journals (Sweden)

    Luis Diez

    2017-05-01

    Full Text Available Despite the increasing presence of wireless communications in everyday life, there exist some voices raising concerns about their adverse effects. One particularly relevant example is the potential impact of the electromagnetic field they induce on the population’s health. Traditionally, very specialized methods and devices (dosimetry have been used to assess the strength of the E-field, with the main objective of checking whether it respects the corresponding regulations. In this paper, we propose a complete novel approach, which exploits the functionality leveraged by a smart city platform. We deploy a number of measuring probes, integrated as sensing devices, to carry out a characterization embracing large areas, as well as long periods of time. This unique platform has been active for more than one year, generating a vast amount of information. We process such information, and the obtained results validate the whole methodology. In addition, we discuss the variation of the E-field caused by cellular networks, considering additional information, such as usage statistics. Finally, we establish the exposure that can be attributed to the base stations within the scenario under analysis.

  20. BREEAM [Building Research Establishment Environmental Assessment Method] BRE [Building Research Establishment] assessment method for buildings

    International Nuclear Information System (INIS)

    Baldwin, R.

    1994-01-01

    Buildings account for a large share of environmental impacts in their construction, use, and demolition. In western Europe, buildings account for ca 50% of primary energy use (hence CO 2 output), far outweighing the contribution of the transport and industrial sectors. Other impacts from building energy use include the use of chemicals such as chlorofluorocarbons for cooling. In the United Kingdom, the Building Research Establishment (BRE) has developed a certificate system for environmental labelling of buildings so that the performance of the building against a set of defined environmental criteria can be made visible to clients. This system thus rewards positive actions to improve the environmental performance of buildings and assists in marketing to an environmentally aware clientele. Issues included in assessments for awarding the certificate are addressed under three main headings: global issues and use of resources, local issues, and indoor issues. Global issues include ozone depletion and CO 2 emissions; local issues include public health and water conservation; and indoor issues include air quality and lighting. 8 refs., 1 tab

  1. Helpful and Hindering Factors in Psychodrama Field Training: A Longitudinal Mixed Methods Study of Student Development

    Directory of Open Access Journals (Sweden)

    Bracha Azoulay

    2018-02-01

    Full Text Available Although the literature indicates that students in mental health professions start to form their professional identity and competence in graduate school, there are few studies on the in-training experience of creative arts therapies students. This mixed methods study examined how five first-year students in a psychodrama master’s degree program in Israel experienced their field training, with the aim of identifying the factors likely to promote or hinder the development of their professional identity and sense of professional ability. Longitudinal data were collected weekly throughout the 20-week field training experience. The students reported qualitatively on helpful and hindering factors and were assessed quantitatively on questionnaires measuring professional identity, perceived demands-abilities fit, client involvement, and therapy session evaluations. A thematic analysis of the students’ reports indicated that a clear and defined setting and structure, observing the instructor as a role model, actively leading parts of the session, and observing fellow students were all helpful factors. The hindering factors included role confusion, issues related to coping with client resistance and disciplinary problems, as well as school end-of-year activities that disrupted the continuity of therapy. The quantitative results indicated that students’ professional identity did not significantly change over the year, whereas a U-shaped curve trajectory characterized the changes in demands-abilities fit and other measures. Students began their field training with an overstated sense of ability that soon declined and later increased. These findings provide indications of which helping and hindering factors should be maximized and minimized, to enhance students’ field training.

  2. Helpful and Hindering Factors in Psychodrama Field Training: A Longitudinal Mixed Methods Study of Student Development.

    Science.gov (United States)

    Azoulay, Bracha; Orkibi, Hod

    2018-01-01

    Although the literature indicates that students in mental health professions start to form their professional identity and competence in graduate school, there are few studies on the in-training experience of creative arts therapies students. This mixed methods study examined how five first-year students in a psychodrama master's degree program in Israel experienced their field training, with the aim of identifying the factors likely to promote or hinder the development of their professional identity and sense of professional ability. Longitudinal data were collected weekly throughout the 20-week field training experience. The students reported qualitatively on helpful and hindering factors and were assessed quantitatively on questionnaires measuring professional identity, perceived demands-abilities fit, client involvement, and therapy session evaluations. A thematic analysis of the students' reports indicated that a clear and defined setting and structure, observing the instructor as a role model, actively leading parts of the session, and observing fellow students were all helpful factors. The hindering factors included role confusion, issues related to coping with client resistance and disciplinary problems, as well as school end-of-year activities that disrupted the continuity of therapy. The quantitative results indicated that students' professional identity did not significantly change over the year, whereas a U-shaped curve trajectory characterized the changes in demands-abilities fit and other measures. Students began their field training with an overstated sense of ability that soon declined and later increased. These findings provide indications of which helping and hindering factors should be maximized and minimized, to enhance students' field training.

  3. Biological methods used to assess surface water quality

    Directory of Open Access Journals (Sweden)

    Szczerbiñska Natalia

    2015-12-01

    Full Text Available In accordance with the guidelines of the Water Framework Directive 2000/60 (WFD, both ecological and chemical statuses determine the assessment of surface waters. The profile of ecological status is based on the analysis of various biological components, and physicochemical and hydromorphological indicators complement this assessment. The aim of this article is to present the biological methods used in the assessment of water status with a special focus on bioassay, as well as to provide a review of methods of monitoring water status. Biological test methods include both biomonitoring and bioanalytics. Water biomonitoring is used to assess and forecast the status of water. These studies aim to collect data on water pollution and forecast its impact. Biomonitoring uses organisms which are characterized by particular vulnerability to contaminants. Bioindicator organisms are algae, fungi, bacteria, larval invertebrates, cyanobacteria, macroinvertebrates, and fish. Bioanalytics is based on the receptors of contaminants that can be biologically active substances. In bioanalytics, biosensors such as viruses, bacteria, antibodies, enzymes, and biotests are used to assess degrees of pollution.

  4. Sequential optimization and reliability assessment method for metal forming processes

    International Nuclear Information System (INIS)

    Sahai, Atul; Schramm, Uwe; Buranathiti, Thaweepat; Chen Wei; Cao Jian; Xia, Cedric Z.

    2004-01-01

    Uncertainty is inevitable in any design process. The uncertainty could be due to the variations in geometry of the part, material properties or due to the lack of knowledge about the phenomena being modeled itself. Deterministic design optimization does not take uncertainty into account and worst case scenario assumptions lead to vastly over conservative design. Probabilistic design, such as reliability-based design and robust design, offers tools for making robust and reliable decisions under the presence of uncertainty in the design process. Probabilistic design optimization often involves double-loop procedure for optimization and iterative probabilistic assessment. This results in high computational demand. The high computational demand can be reduced by replacing computationally intensive simulation models with less costly surrogate models and by employing Sequential Optimization and reliability assessment (SORA) method. The SORA method uses a single-loop strategy with a series of cycles of deterministic optimization and reliability assessment. The deterministic optimization and reliability assessment is decoupled in each cycle. This leads to quick improvement of design from one cycle to other and increase in computational efficiency. This paper demonstrates the effectiveness of Sequential Optimization and Reliability Assessment (SORA) method when applied to designing a sheet metal flanging process. Surrogate models are used as less costly approximations to the computationally expensive Finite Element simulations

  5. Uncertainty on shallow landslide hazard assessment: from field data to hazard mapping

    Science.gov (United States)

    Trefolini, Emanuele; Tolo, Silvia; Patelli, Eduardo; Broggi, Matteo; Disperati, Leonardo; Le Tuan, Hai

    2015-04-01

    Shallow landsliding that involve Hillslope Deposits (HD), the surficial soil that cover the bedrock, is an important process of erosion, transport and deposition of sediment along hillslopes. Despite Shallow landslides generally mobilize relatively small volume of material, they represent the most hazardous factor in mountain regions due to their high velocity and the common absence of warning signs. Moreover, increasing urbanization and likely climate change make shallow landslides a source of widespread risk, therefore the interest of scientific community about this process grown in the last three decades. One of the main aims of research projects involved on this topic, is to perform robust shallow landslides hazard assessment for wide areas (regional assessment), in order to support sustainable spatial planning. Currently, three main methodologies may be implemented to assess regional shallow landslides hazard: expert evaluation, probabilistic (or data mining) methods and physical models based methods. The aim of this work is evaluate the uncertainty of shallow landslides hazard assessment based on physical models taking into account spatial variables such as: geotechnical and hydrogeologic parameters as well as hillslope morphometry. To achieve this goal a wide dataset of geotechnical properties (shear strength, permeability, depth and unit weight) of HD was gathered by integrating field survey, in situ and laboratory tests. This spatial database was collected from a study area of about 350 km2 including different bedrock lithotypes and geomorphological features. The uncertainty associated to each step of the hazard assessment process (e.g. field data collection, regionalization of site specific information and numerical modelling of hillslope stability) was carefully characterized. The most appropriate probability density function (PDF) was chosen for each numerical variable and we assessed the uncertainty propagation on HD strength parameters obtained by

  6. Assessing diabetic retinopathy using two-field digital photography and the influence of JPEG-comoression

    NARCIS (Netherlands)

    Stellingwerf, C; Hardus, PLLJ; Hooymans, JMM

    Objective: To study the effectiveness of two digital 50degrees photographic fields per eye, stored compressed or integrally, in the grading of diabetic retinopathy, in comparison to 35-mm colour slides. Subjects and methods: Two-field digital non-stereoscopic retinal photographs and two-field 35-mm

  7. Quantitative assessment of breast density: comparison of different methods

    International Nuclear Information System (INIS)

    Qin Naishan; Guo Li; Dang Yi; Song Luxin; Wang Xiaoying

    2011-01-01

    Objective: To Compare different methods of quantitative breast density measurement. Methods: The study included sixty patients who underwent both mammography and breast MRI. The breast density was computed automatically on digital mammograms with R2 workstation, Two experienced radiologists read the mammograms and assessed the breast density with Wolfe and ACR classification respectively. Fuzzy C-means clustering algorithm (FCM) was used to assess breast density on MRI. Each assessment method was repeated after 2 weeks. Spearman and Pearson correlations of inter- and intrareader and intermodality were computed for density estimates. Results: Inter- and intrareader correlation of Wolfe classification were 0.74 and 0.65, and they were 0.74 and 0.82 for ACR classification respectively. Correlation between Wolfe and ACR classification was 0.77. High interreader correlation of 0.98 and intrareader correlation of 0.96 was observed with MR FCM measurement. And the correlation between digital mammograms and MRI was high in the assessment of breast density (r=0.81, P<0.01). Conclusion: High correlation of breast density estimates on digital mammograms and MRI FCM suggested the former could be used as a simple and accurate method. (authors)

  8. Methods of assessment of whole body 241Am content

    International Nuclear Information System (INIS)

    Foltanova, S.; Malatova, I.; Klisak, J.

    1998-01-01

    This paper discuss an influence of different skull phantoms on efficiency of the measurement. Description of some methods of an assessment of the 241 Am content in the human skeleton from measurements performed over long bones of the human body is also offered. (authors)

  9. Assessment of Environmental Problems and Methods of Waste ...

    African Journals Online (AJOL)

    This study assessed the environmental problems and methods of waste management in Ado-Ekiti, Nigeria. Waste management is the collection, transportation, processing, recycling or disposal of waste materials, usually the one produced by human activities in an effort to reduce their effect on human health or on local ...

  10. ASSESSMENT OF WORK-SPACE AND WORK-METHOD DESIGNS ...

    African Journals Online (AJOL)

    related injuries among its workforce. This research assessed work-space (WsD) and work-method designs (WmD), level of compliance with recommended standards (RSs) and effects on workers' wellbeing. Clearances for services in 55 supine ...

  11. The Annemarie Roeper Method of Qualitative Assessment: My Journey

    Science.gov (United States)

    Beneventi, Anne

    2016-01-01

    The Annemarie Roeper Method of Qualitative Assessment (QA) establishes an extremely rich set of procedures for revealing students' strengths as well as opportunities for the development of bright young people. This article explores the ways in which the QA process serves as a sterling example of a holistic, authentic system for recognizing…

  12. Myths and Misconceptions about Using Qualitative Methods in Assessment

    Science.gov (United States)

    Harper, Shaun R.; Kuh, George D.

    2007-01-01

    The value of qualitative assessment approaches has been underestimated primarily because they are often juxtaposed against long-standing quantitative traditions and the widely accepted premise that the best research produces generalizable and statistically significant findings. Institutional researchers avoid qualitative methods for at least three…

  13. An assessment method for system innovation and transition (AMSIT)

    NARCIS (Netherlands)

    Bos, Marc W.; Hofman, Erwin; Kuhlmann, Stefan

    2016-01-01

    To address comprehensive system innovations that may occur in a future transition, a suitable ex ante assessment method is required. The technological innovation system approach is useful for the retrospective study of the conditions for success or failure of innovation trajectories, and the

  14. Critical temperature: A quantitative method of assessing cold tolerance

    Science.gov (United States)

    D.H. DeHayes; M.W., Jr. Williams

    1989-01-01

    Critical temperature (Tc), defined as the highest temperature at which freezing injury to plant tissues can be detected, provides a biologically meaningful and statistically defined assessment of the relative cold tolerance of plant tissues. A method is described for calculating critical temperatures in laboratory freezing studies that use...

  15. Reliability and Validity of the Research Methods Skills Assessment

    Science.gov (United States)

    Smith, Tamarah; Smith, Samantha

    2018-01-01

    The Research Methods Skills Assessment (RMSA) was created to measure psychology majors' statistics knowledge and skills. The American Psychological Association's Guidelines for the Undergraduate Major in Psychology (APA, 2007, 2013) served as a framework for development. Results from a Rasch analysis with data from n = 330 undergraduates showed…

  16. A Comparison of Assessment Methods and Raters in Product Creativity

    Science.gov (United States)

    Lu, Chia-Chen; Luh, Ding-Bang

    2012-01-01

    Although previous studies have attempted to use different experiences of raters to rate product creativity by adopting the Consensus Assessment Method (CAT) approach, the validity of replacing CAT with another measurement tool has not been adequately tested. This study aimed to compare raters with different levels of experience (expert ves.…

  17. Assessment of reliability of Greulich and Pyle (gp) method for ...

    African Journals Online (AJOL)

    Background: Greulich and Pyle standards are the most widely used age estimation standards all over the world. The applicability of the Greulich and Pyle standards to populations which differ from their reference population is often questioned. This study aimed to assess the reliability of Greulich and Pyle (GP) method for ...

  18. The AHP method used in assessment of foundry enterprise position

    Directory of Open Access Journals (Sweden)

    J. Szymszal

    2008-10-01

    Full Text Available Complex assessment of activity of a selected foundry enterprise based on a modern AHP (Analytic Hierarchy Process method has beenpresented. Having defined the areas of analysis, which include: marketing (products, distribution channels, sales organisation and client concentration, personnel (skills, managerial abilities, organisation climate, effectiveness of incentives, personnel fluctuations, production (availability of raw materials, technical level of production, effective use of production capacities, organisation and management (foundry structure, organisation culture, management performance, the analysis was made using the weighted sum of evaluations. The second step consisted in a comparative assessment of Foundry position using Saaty’s scale modified by Weber and the AHP method with examinationof a hierarchy structure involving the main (parent problem and its direct evolution into sub-problems. The assessment of Foundryposition made by AHP enables introducing changes and/or innovations which are expected to improve the overall productioneffectiveness.

  19. Investigation by perturbative and analytical method of electronic properties of square quantum well under electric field

    Directory of Open Access Journals (Sweden)

    Mustafa Kemal BAHAR

    2010-06-01

    Full Text Available In this study, the effects of applied electric field on the isolated square quantum well was investigated by analytic and perturbative method. The energy eigen values and wave functions in quantum well were found by perturbative method. Later, the electric field effects were investigated by analytic method, the results of perturbative and analytic method were compared. As well as both of results fit with each other, it was observed that externally applied electric field changed importantly electronic properties of the system.

  20. An investigation of methods for free-field comparison calibration of measurement microphones

    DEFF Research Database (Denmark)

    Barrera-Figueroa, Salvador; Moreno Pescador, Guillermo; Jacobsen, Finn

    2010-01-01

    Free-field comparison calibration of measurement microphones requires that a calibrated reference microphone and a test microphone are exposed to the same sound pressure in a free field. The output voltages of the microphones can be measured either sequentially or simultaneously. The sequential...... method requires the sound field to have good temporal stability. The simultaneous method requires instead that the sound pressure is the same in the positions where the microphones are placed. In this paper the results of the application of the two methods are compared. A third combined method...

  1. Condition Assessment for Wastewater Pipes: Method for Assessing Cracking and Surface Damage of Concrete Pipes

    OpenAIRE

    Hauge, Petter

    2013-01-01

    The objective of the Master Thesis has been to provide an improved method for condition assessment, which will give a better correlation between Condition class and actual Condition of concrete pipes with cracking and/or surface damages. Additionally improvement of the characterization of cracking (SR) and surface (KO) damages was a sub goal.Based on the findings described in my Thesis and my Specialization Project (Hauge 2012), I recommend that the Norwegian condition assessment method based...

  2. Assessment of occupational health problems and physiological stress among the brick field workers of West Bengal, India

    Directory of Open Access Journals (Sweden)

    Banibrata Das

    2014-08-01

    Full Text Available Objectives: The brick field industry is one of the oldest industries in India, which employs a large number of workers of poor socioeconomic status. The main aim of the present investigation is i to determine the prevalence of musculoskeletal disorders among brick field workers, ii to determine the prevalence of respiratory disorders and physiological stress among brick field workers compared to control workers. Material and Methods: For this study, a total of 220 brick field workers and 130 control subjects were selected randomly. The control subjects were mainly involved in hand-intensive jobs. The Modified Nordic Questionnaire was applied to assess the discomfort felt among both groups of workers. Thermal stress was also assessed by measuring the WBGT index. The pulmonary functions were checked using the spirometry. Physiological assessment of the workload was carried out by recording the heart rate and blood pressure of the workers prior to work and just after work in the field. Results: Brick field workers suffered from pain especially in the lower back (98%, hands (93%, knees (86%, wrists (85%, shoulders (76% and neck (65%. Among the brick-making activities, brick field workers felt discomfort during spading for mud collection (98%, carrying bricks (95% and molding (87%. The results showed a significantly lower p value < 0.001 in FVC, FEV1, FEV1/FVC ratio and PEFR in brick field workers compared to the control group. The post-activity heart rate of the brick field workers was 148.6 beats/min, whereas the systolic and diastolic blood pressure results were 152.8 and 78.5 mm/Hg, respectively. Conclusions: This study concludes that health of the brick field workers was highly affected due to working in unhealthy working conditions for a long period of time.

  3. Analysing radio-frequency coil arrays in high-field magnetic resonance imaging by the combined field integral equation method

    Energy Technology Data Exchange (ETDEWEB)

    Wang Shumin; Duyn, Jeff H [Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 10 Center Drive, 10/B1D728, Bethesda, MD 20892 (United States)

    2006-06-21

    We present the combined field integral equation (CFIE) method for analysing radio-frequency coil arrays in high-field magnetic resonance imaging (MRI). Three-dimensional models of coils and the human body were used to take into account the electromagnetic coupling. In the method of moments formulation, we applied triangular patches and the Rao-Wilton-Glisson basis functions to model arbitrarily shaped geometries. We first examined a rectangular loop coil to verify the CFIE method and also demonstrate its efficiency and accuracy. We then studied several eight-channel receive-only head coil arrays for 7.0 T SENSE functional MRI. Numerical results show that the signal dropout and the average SNR are two major concerns in SENSE coil array design. A good design should be a balance of these two factors.

  4. Orthology prediction methods: a quality assessment using curated protein families.

    Science.gov (United States)

    Trachana, Kalliopi; Larsson, Tomas A; Powell, Sean; Chen, Wei-Hua; Doerks, Tobias; Muller, Jean; Bork, Peer

    2011-10-01

    The increasing number of sequenced genomes has prompted the development of several automated orthology prediction methods. Tests to evaluate the accuracy of predictions and to explore biases caused by biological and technical factors are therefore required. We used 70 manually curated families to analyze the performance of five public methods in Metazoa. We analyzed the strengths and weaknesses of the methods and quantified the impact of biological and technical challenges. From the latter part of the analysis, genome annotation emerged as the largest single influencer, affecting up to 30% of the performance. Generally, most methods did well in assigning orthologous group but they failed to assign the exact number of genes for half of the groups. The publicly available benchmark set (http://eggnog.embl.de/orthobench/) should facilitate the improvement of current orthology assignment protocols, which is of utmost importance for many fields of biology and should be tackled by a broad scientific community. Copyright © 2011 WILEY Periodicals, Inc.

  5. Assessing the wettability of unconsolidated porous media using low-field nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Manalo, Florence Pabalan

    2002-01-01

    Methods such as the molarity of ethanol droplet (MED) test and water drop penetration test (WDPT) are commonly used to measure soil wettability because these tests are quick and easy to perform. However, they are not without limitations. This thesis proposes using a low-field NMR relaxometer as an alternative method of assessing soil wettability. This instrument is able to discriminate surface bound fluid from bulk fluid Fluid bound to the surface relaxes quickly and produces signal amplitude peaks at low transverse relaxation time (T 2 ) values. Bulk fluid , on the other hand, relaxes much more slowly and signal amplitude peaks consequently appear at higher T 2 values. An extensive experimental program was designed to test the above hypothesis. Hundreds of NMR measurements were performed on clays, humic acids, fulvic acids, clean sands, sands coated with organic matter, wettable soils and water-repellent soils exposed to distilled water and kerosene. The results confirm the hypothesis and show clearly that NMR does detect preferentially water-wet and water-repellent samples. The differences in the solid-fluid interactions between water and unconsolidated porous media with varying wetting preferences also allow for the use of low-field NMR to detect wettability alteration and to monitor fluid uptake in unconsolidated porous media. The advantages of using this tool include obtaining reproducible results quickly, using only small amounts of sample for analysis, and calculating the mass of water without performing a mass balance calculation. (author)

  6. Applying Multi-Criteria Analysis Methods for Fire Risk Assessment

    Directory of Open Access Journals (Sweden)

    Pushkina Julia

    2015-11-01

    Full Text Available The aim of this paper is to prove the application of multi-criteria analysis methods for optimisation of fire risk identification and assessment process. The object of this research is fire risk and risk assessment. The subject of the research is studying the application of analytic hierarchy process for modelling and influence assessment of various fire risk factors. Results of research conducted by the authors can be used by insurance companies to perform the detailed assessment of fire risks on the object and to calculate a risk extra charge to an insurance premium; by the state supervisory institutions to determine the compliance of a condition of object with requirements of regulations; by real state owners and investors to carry out actions for decrease in degree of fire risks and minimisation of possible losses.

  7. Bioactive conformational generation of small molecules: A comparative analysis between force-field and multiple empirical criteria based methods

    Directory of Open Access Journals (Sweden)

    Jiang Hualiang

    2010-11-01

    Full Text Available Abstract Background Conformational sampling for small molecules plays an essential role in drug discovery research pipeline. Based on multi-objective evolution algorithm (MOEA, we have developed a conformational generation method called Cyndi in the previous study. In this work, in addition to Tripos force field in the previous version, Cyndi was updated by incorporation of MMFF94 force field to assess the conformational energy more rationally. With two force fields against a larger dataset of 742 bioactive conformations of small ligands extracted from PDB, a comparative analysis was performed between pure force field based method (FFBM and multiple empirical criteria based method (MECBM hybrided with different force fields. Results Our analysis reveals that incorporating multiple empirical rules can significantly improve the accuracy of conformational generation. MECBM, which takes both empirical and force field criteria as the objective functions, can reproduce about 54% (within 1Å RMSD of the bioactive conformations in the 742-molecule testset, much higher than that of pure force field method (FFBM, about 37%. On the other hand, MECBM achieved a more complete and efficient sampling of the conformational space because the average size of unique conformations ensemble per molecule is about 6 times larger than that of FFBM, while the time scale for conformational generation is nearly the same as FFBM. Furthermore, as a complementary comparison study between the methods with and without empirical biases, we also tested the performance of the three conformational generation methods in MacroModel in combination with different force fields. Compared with the methods in MacroModel, MECBM is more competitive in retrieving the bioactive conformations in light of accuracy but has much lower computational cost. Conclusions By incorporating different energy terms with several empirical criteria, the MECBM method can produce more reasonable conformational

  8. Analysis of risk assessment methods for goods trucking

    Directory of Open Access Journals (Sweden)

    Yunyazova A.O.

    2018-04-01

    Full Text Available the article considers models of risk assessment that can be applied to cargo transportation, for forecasting possible damage in the form of financial and material costs in order to reduce the percentage of probability of their occurrence. The analysis of risk by the method «Criterion. Event. Rule" is represented. This method is based on the collection of information by various methods, assigning an assessment to the identified risks, ranking and formulating a report on the analysis. It can be carried out as a fully manual mechanical method of information collecting and performing calculations or can be brought to an automated level from data collection to the delivery of finished results (but in this case some nuances that could significantly influence the outcome of the analysis can be ignored. The expert method is of particular importance, since it relies directly on human experience. In this case, a special role is played by the human factor. The collection of information and the assigned assessments to risk groups depend on the extent to which experts agree on this issue. The smaller the fluctuations in the values ​​of the estimates of the experts, the more accurate and optimal the results will be.

  9. Standard guide for three methods of assessing buried steel tanks

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1998-01-01

    1.1 This guide covers procedures to be implemented prior to the application of cathodic protection for evaluating the suitability of a tank for upgrading by cathodic protection alone. 1.2 Three procedures are described and identified as Methods A, B, and C. 1.2.1 Method A—Noninvasive with primary emphasis on statistical and electrochemical analysis of external site environment corrosion data. 1.2.2 Method B—Invasive ultrasonic thickness testing with external corrosion evaluation. 1.2.3 Method C—Invasive permanently recorded visual inspection and evaluation including external corrosion assessment. 1.3 This guide presents the methodology and the procedures utilizing site and tank specific data for determining a tank's condition and the suitability for such tanks to be upgraded with cathodic protection. 1.4 The tank's condition shall be assessed using Method A, B, or C. Prior to assessing the tank, a preliminary site survey shall be performed pursuant to Section 8 and the tank shall be tightness test...

  10. Total System Performance Assessment-License Application Methods and Approach

    Energy Technology Data Exchange (ETDEWEB)

    J. McNeish

    2002-09-13

    ''Total System Performance Assessment-License Application (TSPA-LA) Methods and Approach'' provides the top-level method and approach for conducting the TSPA-LA model development and analyses. The method and approach is responsive to the criteria set forth in Total System Performance Assessment Integration (TSPAI) Key Technical Issue (KTI) agreements, the ''Yucca Mountain Review Plan'' (CNWRA 2002 [158449]), and 10 CFR Part 63. This introductory section provides an overview of the TSPA-LA, the projected TSPA-LA documentation structure, and the goals of the document. It also provides a brief discussion of the regulatory framework, the approach to risk management of the development and analysis of the model, and the overall organization of the document. The section closes with some important conventions that are utilized in this document.

  11. Total System Performance Assessment - License Application Methods and Approach

    International Nuclear Information System (INIS)

    McNeish, J.

    2003-01-01

    ''Total System Performance Assessment-License Application (TSPA-LA) Methods and Approach'' provides the top-level method and approach for conducting the TSPA-LA model development and analyses. The method and approach is responsive to the criteria set forth in Total System Performance Assessment Integration (TSPAI) Key Technical Issues (KTIs) identified in agreements with the U.S. Nuclear Regulatory Commission, the ''Yucca Mountain Review Plan'' (YMRP), ''Final Report'' (NRC 2003 [163274]), and the NRC final rule 10 CFR Part 63 (NRC 2002 [156605]). This introductory section provides an overview of the TSPA-LA, the projected TSPA-LA documentation structure, and the goals of the document. It also provides a brief discussion of the regulatory framework, the approach to risk management of the development and analysis of the model, and the overall organization of the document. The section closes with some important conventions that are used in this document

  12. Statistical methods for assessing agreement between continuous measurements

    DEFF Research Database (Denmark)

    Sokolowski, Ineta; Hansen, Rikke Pilegaard; Vedsted, Peter

    Background: Clinical research often involves study of agreement amongst observers. Agreement can be measured in different ways, and one can obtain quite different values depending on which method one uses. Objective: We review the approaches that have been discussed to assess the agreement between...... continuous measures and discuss their strengths and weaknesses. Different methods are illustrated using actual data from the `Delay in diagnosis of cancer in general practice´ project in Aarhus, Denmark. Subjects and Methods: We use weighted kappa-statistic, intraclass correlation coefficient (ICC......), concordance coefficient, Bland-Altman limits of agreement and percentage of agreement to assess the agreement between patient reported delay and doctor reported delay in diagnosis of cancer in general practice. Key messages: The correct statistical approach is not obvious. Many studies give the product...

  13. Survey and assessment of conventional software verification and validation methods

    International Nuclear Information System (INIS)

    Miller, L.A.; Groundwater, E.; Mirsky, S.M.

    1993-04-01

    By means of a literature survey, a comprehensive set of methods was identified for the verification and validation of conventional software. The 134 methods so identified were classified according to their appropriateness for various phases of a developmental lifecycle -- requirements, design, and implementation; the last category was subdivided into two, static testing and dynamic testing methods. The methods were then characterized in terms of eight rating factors, four concerning ease-of-use of the methods and four concerning the methods' power to detect defects. Based on these factors, two measurements were developed to permit quantitative comparisons among methods, a Cost-Benefit metric and an Effectiveness Metric. The Effectiveness Metric was further refined to provide three different estimates for each method, depending on three classes of needed stringency of V ampersand V (determined by ratings of a system's complexity and required-integrity). Methods were then rank-ordered for each of the three classes in terms of their overall cost-benefits and effectiveness. The applicability was then assessed of each method for the four identified components of knowledge-based and expert systems, as well as the system as a whole

  14. Analytical resource assessment method for continuous (unconventional) oil and gas accumulations - The "ACCESS" Method

    Science.gov (United States)

    Crovelli, Robert A.; revised by Charpentier, Ronald R.

    2012-01-01

    The U.S. Geological Survey (USGS) periodically assesses petroleum resources of areas within the United States and the world. The purpose of this report is to explain the development of an analytic probabilistic method and spreadsheet software system called Analytic Cell-Based Continuous Energy Spreadsheet System (ACCESS). The ACCESS method is based upon mathematical equations derived from probability theory. The ACCESS spreadsheet can be used to calculate estimates of the undeveloped oil, gas, and NGL (natural gas liquids) resources in a continuous-type assessment unit. An assessment unit is a mappable volume of rock in a total petroleum system. In this report, the geologic assessment model is defined first, the analytic probabilistic method is described second, and the spreadsheet ACCESS is described third. In this revised version of Open-File Report 00-044 , the text has been updated to reflect modifications that were made to the ACCESS program. Two versions of the program are added as appendixes.

  15. Assessment and comparison of methods for solar ultraviolet radiation measurements

    Energy Technology Data Exchange (ETDEWEB)

    Leszczynski, K

    1995-06-01

    In the study, the different methods to measure the solar ultraviolet radiation are compared. The methods included are spectroradiometric, erythemally weighted broadband and multi-channel measurements. The comparison of the different methods is based on a literature review and assessments of optical characteristics of the spectroradiometer Optronic 742 of the Finnish Centre for Radiation and Nuclear Safety (STUK) and of the erythemally weighted Robertson-Berger type broadband radiometers Solar Light models 500 and 501 of the Finnish Meteorological Institute and STUK. An introduction to the sources of error in solar UV measurements, to methods for radiometric characterization of UV radiometers together with methods for error reduction are presented. Reviews on experiences from world-wide UV monitoring efforts and instrumentation as well as on the results from international UV radiometer intercomparisons are also presented. (62 refs.).

  16. Assessment and comparison of methods for solar ultraviolet radiation measurements

    International Nuclear Information System (INIS)

    Leszczynski, K.

    1995-06-01

    In the study, the different methods to measure the solar ultraviolet radiation are compared. The methods included are spectroradiometric, erythemally weighted broadband and multi-channel measurements. The comparison of the different methods is based on a literature review and assessments of optical characteristics of the spectroradiometer Optronic 742 of the Finnish Centre for Radiation and Nuclear Safety (STUK) and of the erythemally weighted Robertson-Berger type broadband radiometers Solar Light models 500 and 501 of the Finnish Meteorological Institute and STUK. An introduction to the sources of error in solar UV measurements, to methods for radiometric characterization of UV radiometers together with methods for error reduction are presented. Reviews on experiences from world-wide UV monitoring efforts and instrumentation as well as on the results from international UV radiometer intercomparisons are also presented. (62 refs.)

  17. MEASUREMENTS OF STRAIN FIELDS DUE TO NANOSCALE PRECIPITATES USING THE PHASE IMAGE METHOD

    Directory of Open Access Journals (Sweden)

    Patricia Donnadieu

    2011-05-01

    Full Text Available Owing the phase image method (Hytch, 1998, strain fields can be derived from HREM images. The method is here applied to the nanoscale precipitates responsible for hardening in Aluminum alloys. Since the method is a very sensitive one, we have examined the impact of several aspects of the image quality (noise, fluctuations, distortion. The strain field information derived from the HREM image analysis is further introduced in a simulation of the dislocation motion in the matrix.

  18. Improving Hyperspectral Image Classification Method for Fine Land Use Assessment Application Using Semisupervised Machine Learning

    Directory of Open Access Journals (Sweden)

    Chunyang Wang

    2015-01-01

    Full Text Available Study on land use/cover can reflect changing rules of population, economy, agricultural structure adjustment, policy, and traffic and provide better service for the regional economic development and urban evolution. The study on fine land use/cover assessment using hyperspectral image classification is a focal growing area in many fields. Semisupervised learning method which takes a large number of unlabeled samples and minority labeled samples, improving classification and predicting the accuracy effectively, has been a new research direction. In this paper, we proposed improving fine land use/cover assessment based on semisupervised hyperspectral classification method. The test analysis of study area showed that the advantages of semisupervised classification method could improve the high precision overall classification and objective assessment of land use/cover results.

  19. Assessment of visual function by optical coherence tomography and visual field for craniopharyngioma patients

    Directory of Open Access Journals (Sweden)

    Yang Tang

    2015-09-01

    Full Text Available AIM:To analyze the differences and correlations between ganglion cell complex(GCC, peripapillary retinal nerve fiber layer(pRNFLand mean defect(MD, mean sensitivity(MSof visual field(VFin craniopharyngioma patients, to evaluate the feasibility of optical coherence tomography(OCTin diagnosis of the visual pathway damage of craniopharyngioma patients.METHODS:Ninety-five craniopharyngioma patients treated in Beijing Tiantan Hospital, from September 2014 to April 2015 received the VF test by Octopus 900 automated perimeter with the central 30 degree program and the mean thickness measurements of GCC and pRNFL by RTVue OCT. Spearman rank correlation coefficient(rswas used to assess the correlation between GCC, pRNFL and MD, MS. The changes of VF and optic disc were analyzed. RESULTS: Abnormal pRNFL findings occurred in 53.1%(93/175, which included optic disk edema 3.4%(6/175, atrophic changes of optic nerve 47.4%(83/175and glaucoma-like optic neuropathy 7.4%(13/175. Various visual field defect was 71.4%(125/175. The average thickness of binocular pRNFL(rsOD=-0.411, rsOS=-0.354and GCC(rsOD=-0.400, rsOS=-0.314had correlation with MD(PrsOD=0.412, rsOS=0.342and GCC(rsOD=0.414, rsOS=0.299had correlation with MS(PCONCLUSION: The average thickness of pRNFL and GCC has correlation with VF damage, can evaluate the optic nerve damage of craniopharyngioma patients quantitatively. The thinner the thickness of pRNFL and GCC is, the serious damage of visual function is. During the clinical work, visual field test combined with OCT are helpful to find and assess the damage of visual pathway and prognosis.

  20. New method of scoliosis assessment: preliminary results using computerized photogrammetry.

    Science.gov (United States)

    Aroeira, Rozilene Maria Cota; Leal, Jefferson Soares; de Melo Pertence, Antônio Eustáquio

    2011-09-01

    A new method for nonradiographic evaluation of scoliosis was independently compared with the Cobb radiographic method, for the quantification of scoliotic curvature. To develop a protocol for computerized photogrammetry, as a nonradiographic method, for the quantification of scoliosis, and to mathematically relate this proposed method with the Cobb radiographic method. Repeated exposure to radiation of children can be harmful to their health. Nevertheless, no nonradiographic method until now proposed has gained popularity as a routine method for evaluation, mainly due to a low correspondence to the Cobb radiographic method. Patients undergoing standing posteroanterior full-length spine radiographs, who were willing to participate in this study, were submitted to dorsal digital photography in the orthostatic position with special surface markers over the spinous process, specifically the vertebrae C7 to L5. The radiographic and photographic images were sent separately for independent analysis to two examiners, trained in quantification of scoliosis for the types of images received. The scoliosis curvature angles obtained through computerized photogrammetry (the new method) were compared to those obtained through the Cobb radiographic method. Sixteen individuals were evaluated (14 female and 2 male). All presented idiopathic scoliosis, and were between 21.4 ± 6.1 years of age; 52.9 ± 5.8 kg in weight; 1.63 ± 0.05 m in height, with a body mass index of 19.8 ± 0.2. There was no statistically significant difference between the scoliosis angle measurements obtained in the comparative analysis of both methods, and a mathematical relationship was formulated between both methods. The preliminary results presented demonstrate equivalence between the two methods. More studies are needed to firmly assess the potential of this new method as a coadjuvant tool in the routine following of scoliosis treatment.