Sample records for reservoir limits test

  1. Well testing in gas hydrate reservoirs


    Kome, Melvin Njumbe


    Reservoir testing and analysis are fundamental tools in understanding reservoir hydraulics and hence forecasting reservoir responses. The quality of the analysis is very dependent on the conceptual model used in investigating the responses under different flowing conditions. The use of reservoir testing in the characterization and derivation of reservoir parameters is widely established, especially in conventional oil and gas reservoirs. However, with depleting conventional reserves, the ...

  2. Mechanical Testing Development for Reservoir Forgings

    Energy Technology Data Exchange (ETDEWEB)

    Wenski, E.G.


    The goal of this project was to determine the machining techniques and testing capabilities required for mechanical property evaluation of commercially procured reservoir forgings. Due to the small size of these specific forgings, specialized methods are required to adequately machine and test these sub-miniature samples in accordance with the requirements of ASTM-E8 and ASTM-E9. At the time of project initiation, no capability existed at Federal Manufacturing & Technologies (FM&T) to verify the physical properties of these reservoirs as required on the drawing specifications. The project determined the sample definitions, machining processes, and testing procedures to verify the physical properties of the reservoir forgings; specifically, tensile strength, yield strength, reduction of area, and elongation. In addition, a compression test method was also developed to minimize sample preparation time and provide a more easily machined test sample while maintaining the physical validation of the forging.

  3. Petroleum reservoir data for testing simulation models

    Energy Technology Data Exchange (ETDEWEB)

    Lloyd, J.M.; Harrison, W.


    This report consists of reservoir pressure and production data for 25 petroleum reservoirs. Included are 5 data sets for single-phase (liquid) reservoirs, 1 data set for a single-phase (liquid) reservoir with pressure maintenance, 13 data sets for two-phase (liquid/gas) reservoirs and 6 for two-phase reservoirs with pressure maintenance. Also given are ancillary data for each reservoir that could be of value in the development and validation of simulation models. A bibliography is included that lists the publications from which the data were obtained.

  4. Installation of a Devonian Shale Reservoir Testing Facility and acquisition of reservoir property measurements

    Energy Technology Data Exchange (ETDEWEB)

    Locke, C.D.; Salamy, S.P.


    In October, a contract was awarded for the Installation of a Devonian Shale Reservoir Testing Facility and Acquisition of Reservoir Property measurements from wells in the Michigan, Illinois, and Appalachian Basins. Geologic and engineering data collected through this project will provide a better understanding of the mechanisms and conditions controlling shale gas production. This report summarizes the results obtained from the various testing procedures used at each wellsite and the activities conducted at the Reservoir Testing Facility.

  5. Installation of a Devonian Shale Reservoir Testing Facility and acquisition of reservoir property measurements. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Locke, C.D.; Salamy, S.P.


    In October, a contract was awarded for the Installation of a Devonian Shale Reservoir Testing Facility and Acquisition of Reservoir Property measurements from wells in the Michigan, Illinois, and Appalachian Basins. Geologic and engineering data collected through this project will provide a better understanding of the mechanisms and conditions controlling shale gas production. This report summarizes the results obtained from the various testing procedures used at each wellsite and the activities conducted at the Reservoir Testing Facility.

  6. Testing the limits (United States)

    Loring, David W.; Bauer, Russell M.


    The Wechsler Adult Intelligence Scale (WAIS) and the Wechsler Memory Scale (WMS) are 2 of the most common psychological tests used in clinical care and research in neurology. Newly revised versions of both instruments (WAIS-IV and WMS-IV) have recently been published and are increasingly being adopted by the neuropsychology community. There have been significant changes in the structure and content of both scales, leading to the potential for inaccurate patient classification if algorithms developed using their predecessors are employed. There are presently insufficient clinical data in neurologic populations to insure their appropriate application to neuropsychological evaluations. We provide a perspective on these important new neuropsychological instruments, comment on the pressures to adopt these tests in the absence of an appropriate evidence base supporting their incremental validity, and describe the potential negative impact on both patient care and continuing research applications. PMID:20177123

  7. Successful flow testing of a gas reservoir in 3,500 feet of water

    International Nuclear Information System (INIS)

    Shaughnessy, J.M.; Carpenter, R.S.; Coleman, R.A.; Jackson, C.W.


    The test of Viosca Knoll Block 957 Well No. 1 Sidetrack No. 2 was Amoco Production Co.'s deepest test from a floating rig. Viosca Knoll 957 is 115 miles southeast of New Orleans in 3,500 ft of water. The test, at a record water depth for the Gulf of Mexico, also set a world water-depth record for testing a gas reservoir. Safety to crew and the environmental were top priorities during the planning. A team consisting of drilling, completion, reservoir, and facilities engineers and a foreman were assigned to plan and implement the test. Early planning involved field, service company, and engineering groups. Every effort was made to identify potential problems and to design the system to handle them. This paper reports that the goals of the test were to determine reservoir properties and reservoir limits. Several significant challenges were involved in the well test. The reservoir was gas with a potentially significant condensate yield. The ability to dispose of the large volumes of produced fluids safely without polluting was critical to maintaining uninterrupted flow. Potential shut-in surface pressure was 6,500 psi. Seafloor temperature in 3,500 ft of water was 39 degrees F

  8. Test limits using correlated measurements

    NARCIS (Netherlands)

    Albers, Willem/Wim; Arts, G.R.J.; Kallenberg, W.C.M.


    In the standard model for inspection of manufactured parts measurements of the characteristic of interest are subject to, typically small, measurement errors. This leads to test limits which are slightly more strict than the corresponding specification limits. Quite often, however, such direct

  9. The Limited Test Ban Treaty

    International Nuclear Information System (INIS)

    Loeb, B.S.


    This paper discusses the Limited Test Ban Treaty which came at the end of nearly five years of frustrated efforts to obtain a comprehensive test ban. Negotiations toward that end had begun in October 1958. At the same time a voluntary, informal moratorium on tests was initiated. The negotiations soon stalled over the Soviet Union's resistance to internationally supervised inspections on its soil. In April 1959 a phased ban that was to be limited at first to atmospheric tests conducted below an altitude of 50 kilometers. Such tests were thought to be easily verifiable. The Soviets rejected this idea and continued to insist that a complete test ban need not require numerous inspections. The two sides nevertheless appeared to be nearing agreement on a treaty to ban all but relatively small underground tests when, in May 1960, an U.S. U-2 reconnaissance plane was shot down over Soviet territory. After a thorough review of the U.S. position, the Kennedy administration proposed in April 1961 a draft treaty that made several concessions toward the Soviet position. Nevertheless, the Soviets, still disagreeing with the provisions for verification and with the makeup of the control organization, rejected it

  10. Testing the Limits on Drug Limits. (United States)

    Dowling-Sendor, Benjamin


    In an Oklahoma case, absence of a documented drug problem among students in nonathletic extracurricular activities led the10th Circuit Court to strike down the district's policy as unreasonable and unconstitutional. Imposing random, suspicionless drug-testing policies for all students attending school might violate the Fourth Amendment. (MLH)

  11. Laboratory evaluation of the limitations of positive pressure safety valves on hard-shell venous reservoirs. (United States)

    Almany, Daniel K; Sistino, Joseph J


    Vacuum-assisted venous drainage (VAVD) is a technique used to increase venous return during cardiopulmonary bypass (CPB). However, VAVD has created some new safety concerns. One potential problem is the pressurization of the venous reservoir in the event of vacuum failure. To prevent this overpressurization, a positive pressure release valve (PPRV) is placed on the venous reservoir. The purpose of this study was to determine if there is a difference in the pressurization of venous reservoirs using various PPRVs. The method of this study included evaluation of four different venous reservoirs and their associated PPRVs. Each reservoir was completely sealed, and two roller pumps with 1/4-in tubing were connected to the reservoir suction inlet. The roller pumps were calibrated, and a disposable pressure transducer was used to measure pressure at the venous inlet. Each reservoir was first sealed and then pressurized to test the occlusion of the roller heads. The PPRVs were tested by measuring the venous inlet pressure at a range of suction flow rates from 0-5 L/min. Linear regression analysis was performed to predict the venous inlet pressure from the rate of suction flow for each PPRV. The PPRV in the Baxter, Gish, and Gambro reservoirs maintained a low reservoir pressure (40 mmHg) even at low flow rates (1-2 L/min). It is recommended that any reservoir used for VAVD be evaluated in a similar manner to determine whether it is safe under the maximal suction and vent flow conditions possible during clinical practice.


    Directory of Open Access Journals (Sweden)

    Norica-Felicia BUCUR


    Full Text Available Global market forces have determined not only higher education institutions all over the world to include ESP courses in their curriculum to enhance their students’ future employability, but also public and private organisations to offer their employees the opportunity to attend ESP courses in order to meet the continuously growing ESP needs. From this perspective, ESP compentence could become a subcomponent of one of the key competences for lifelong learning, communication in foreign languages. Therefore assessing ESP competence seems to acquire paramount importance since stakeholders need accurate information about the ESP learners’ abilities to cope with specific language tasks. This article offers a concise overview of the principles and practices of ESP assessment, a detailed description of the features of ESP tests, while focusing particularly on the limits of ESP tests in order to identify possible solutions to overcome them.

  13. Sodium nitrate combustion limit tests

    International Nuclear Information System (INIS)

    Beitel, G.A.


    Sodium nitrate is a powerful solid oxidant. Energetically, it is capable of exothermically oxidizing almost any organic material. Rate-controlling variables such as temperature, concentration of oxidant, concentration of fuel, thermal conductivity, moisture content, size, and pressure severely limit the possibility of a self-supported exothermic reaction (combustion). The tests reported in this document were conducted on one-gram samples at atmospheric pressure. Below 380 0 C, NaNO 3 was stable and did not support combustion. At moisture concentrations above 22 wt percent, exothermic reactions did not propagate in even the most energetic and reactive compositions. Fresh resin and paraffin were too volatile to enable a NaNO 2 -supported combustion process to propagate. Concentrations of NaNO 3 above 95 wt percent or below 35 wt percent did not react with enough energy release to support combustion. The influence of sample size and confining pressure, both important factors, was not investigated in this study

  14. Extracting maximum petrophysical and geological information from a limited reservoir database

    Energy Technology Data Exchange (ETDEWEB)

    Ali, M.; Chawathe, A.; Ouenes, A. [New Mexico Institute of Mining and Technology, Socorro, NM (United States)] [and others


    The characterization of old fields lacking sufficient core and log data is a challenging task. This paper describes a methodology that uses new and conventional tools to build a reliable reservoir model for the Sulimar Queen field. At the fine scale, permeability measured on a fine grid with a minipermeameter was used in conjunction with the petrographic data collected on multiple thin sections. The use of regression analysis and a newly developed fuzzy logic algorithm led to the identification of key petrographic elements which control permeability. At the log scale, old gamma ray logs were first rescaled/calibrated throughout the entire field for consistency and reliability using only four modem logs. Using data from one cored well and the rescaled gamma ray logs, correlations between core porosity, permeability, total water content and gamma ray were developed to complete the small scale characterization. At the reservoir scale, outcrop data and the rescaled gamma logs were used to define the reservoir structure over an area of ten square miles where only 36 wells were available. Given the structure, the rescaled gamma ray logs were used to build the reservoir volume by identifying the flow units and their continuity. Finally, history-matching results constrained to the primary production were used to estimate the dynamic reservoir properties such as relative permeabilities to complete the characterization. The obtained reservoir model was tested by forecasting the waterflood performance and which was in good agreement with the actual performance.

  15. Analysis of injection tests in liquid-dominated geothermal reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Benson, S.M.


    The objective was to develop procedures for analyzing nonisothermal injection test data during the early phases of injection. In particular, methods for determining the permeability-thickness of the formation, skin factor of the well and tracking the movement of the thermal front have been developed. The techniques developed for interpreting injection pressure transients are closely akin to conventional groundwater and petroleum techniques for evaluating these parameters. The approach taken was to numerically simulate injection with a variety of temperatures, reservoir parameters and flowrates, in order to determine the characteristic responses due to nonisothermal injection. Two characteristic responses were identified: moving front dominated behavior and composite reservoir behavior. Analysis procedures for calculating the permeability-thickness of the formation and the skin factor of the well have been developed for each of these cases. In order to interpret the composite reservior behavior, a new concept has been developed; that of a ''fluid skin factor'', which accounts for the steady-state pressure buildup due to the region inside the thermal front. Based on this same concept, a procedure for tracking the movement of the thermal front has been established. The results also identify the dangers of not accounting the nonisothermal effects when analyzing injection test data. Both the permeability-thickness and skin factor of the well can be grossly miscalculated if the effects of the cold-region around the well are not taken into consideration. 47 refs., 30 figs., 14 tabs.

  16. Advanced productivity forecast using petrophysical wireline data calibrated with MDT tests and numerical reservoir simulation

    Energy Technology Data Exchange (ETDEWEB)

    Andre, Carlos de [PETROBRAS, Rio de Janeiro, RJ (Brazil); Canas, Jesus A.; Low, Steven; Barreto, Wesley [Schlumberger, Houston, TX (United States)


    This paper describes an integrated and rigorous approach for viscous and middle oil reservoir productivity evaluation using petrophysical models calibrated with permeability derived from mini tests (Dual Packer) and Vertical Interference Tests (VIT) from open hole wire line testers (MDT SLB TM). It describes the process from Dual Packer Test and VIT pre-job design, evaluation via analytical and inverse simulation modeling, calibration and up scaling of petrophysical data into a numerical model, history matching of Dual Packer Tests and VIT with numerical simulation modeling. Finally, after developing a dynamic calibrated model, we perform productivity forecasts of different well configurations (vertical, horizontal and multilateral wells) for several deep offshore oil reservoirs in order to support well testing activities and future development strategies. The objective was to characterize formation static and dynamic properties early in the field development process to optimize well testing design, extended well test (EWT) and support the development strategies in deep offshore viscous oil reservoirs. This type of oil has limitations to flow naturally to surface and special lifting equipment is required for smooth optimum well testing/production. The integrated analysis gave a good overall picture of the formation, including permeability anisotropy and fluid dynamics. Subsequent analysis of different well configurations and lifting schemes allows maximizing formation productivity. The simulation and calibration results are compared to measured well test data. Results from this work shows that if the various petrophysical and fluid properties sources are integrated properly an accurate well productivity model can be achieved. If done early in the field development program, this time/knowledge gain could reduce the risk and maximize the development profitability of new blocks (value of the information). (author)

  17. Biological justification for fish harvest limits in the Zaporizhzhya (Dnipro reservoir for 2017

    Directory of Open Access Journals (Sweden)

    O. Marenkov


    Full Text Available Purpose. To analyze the current state of the populations of roach, bream, pikeperch and silver bream in the Zaporozhye (Dnipro reservoir and to determine the acceptable amounts of commercial harvest of these fish species for 2017 by determining scientifically justified limits. Methodology. The summarized results of ichthyological studies conducted during 2010–2016 years were used during the research. The materials were collected in the Zaporizhzhya (Dnipro Reservoir using standard fish sampling methods. A set of standard fishing gears (gill nets with mesh sizes of 30–120 mm was used for studying fish fauna. Juvenile fish were caught in the third decade of July – first decade of August using a beach seine of 10 m in length. The processing of collected samples was conducted by conventional methods. Findings. We studied the current state of commercial fish populations, the exploitation of which is limited (roach, bream, pikeperch, silver bream. We determined the basic biological parameters of these species, determined the age and sex structure of their populations and assessed their stocks. Based on these data, we determined the rates of natural, fishing and total mortality and calculated the amounts of commercial catches of the investigated fish species. With an optimum catch of the roach not exceeding 25% of the calculated stock, we recommended to set a limit on the catch of this species for 2017 as 190 tons. Next year, it is advisable to set a limit for the bream catch not higher than 88 tons. Due to a critical state of the pikeperch stock in the Zaporozhye (Dnieper reservoir, the recommended limit of its catch for 2017 should not exceed 14 tons. The estimated catch limit for the silver bream for the following year is recommend to be 70 tons. The harvst of these fish species within the proposed limits will allow carrying out their commercial exploitation without environmental damage. Originality. We presented the results of the study of

  18. Using a Bayesian Probabilistic Forecasting Model to Analyze the Uncertainty in Real-Time Dynamic Control of the Flood Limiting Water Level for Reservoir Operation

    DEFF Research Database (Denmark)

    Liu, Dedi; Li, Xiang; Guo, Shenglian


    Dynamic control of the flood limiting water level (FLWL) is a valuable and effective way to maximize the benefits from reservoir operation without exceeding the design risk. In order to analyze the impacts of input uncertainty, a Bayesian forecasting system (BFS) is adopted. Applying quantile water...... inflow values and their uncertainties obtained from the BFS, the reservoir operation results from different schemes can be analyzed in terms of benefits, dam safety, and downstream impacts during the flood season. When the reservoir FLWL dynamic control operation is implemented, there are two fundamental......, also deterministic water inflow was tested. The proposed model in the paper emphasizes the importance of analyzing the uncertainties of the water inflow forecasting system for real-time dynamic control of the FLWL for reservoir operation. For the case study, the selected quantile inflow from...

  19. The lower limit of the flowing pore throat radius in the extra-low permeability reservoir (United States)

    Xiang, Junhui; Yin, Daiyin


    In this paper, a method for determining the lower limit of flowing pore throat radius of the extra low permeability reservoir in the periphery of Changyuan Oil Fields is given. The capillary pressure curve is divided into linear type and concave type. The nuclear magnetic resonance (NMR) T2 spectrum is divided into 3 types: the left peak is greater than the right peak, the left peak is equal to the right one, and the left peak is smaller than the right one. The method for determining the lower limit of flowing pore throat radius is, first, converting the nuclear magnetic resonance T2 spectrum to the capillary pressure curve calculated, then fitting the capillary pressure curves measured by the constant speed mercury injection experiment and the capillary pressure curve calculated. After finding the relevant parameters, converting the horizontal axis of the NMR T2 spectra from relaxation time to pore throat radius, and the pore throat radius corresponding to the T2 cutoff value is the lower limit of the flowing pore throat radius. The lower limit of the flowing pore throat radius of the extra low permeability Fuyang Oil Reservoir in the periphery of Changyuan Oil Fields is about 0.68μm

  20. Nuclear register applications and pressure tests to foresee reservoirs exploitation with water drive

    International Nuclear Information System (INIS)

    Osorio F, X.; Redosado G, V.


    This paper illustrates how the pulsed neutron log and well test analysis aid proper reservoir management in strong water reservoirs. These techniques have been applied to Cetico reservoir which belongs to Corrientes Field which is located in the Peruvian Jungle. Corrientes is the most important field operated by PETROPERU S.A. As a result of the analysis we current know the present areal water saturation distribution and also have improve the reservoir characterization al of which is being used for increasing the oil production and reserves. (author). 4 refs, 7 figs, 3 tabs

  1. Study on the lower limits of petrophysical parameters of the Upper Paleozoic tight sandstone gas reservoirs in the Ordos Basin, China

    Directory of Open Access Journals (Sweden)

    Huiying Cui


    Full Text Available There hasn't been a clear understanding of the lower limits of petrophysical parameters of tight sandstone gas reservoirs so far. However, it is an important question directly related to exploration and development strategies. Research methods of the lower limits of petrophysical parameters are reviewed. The new minimum flow pore throat radius method is used to determine the lower limit of flow pore throat radius. The relative permeability curve method, irreducible water saturation method, and testing method, are used to determine the lower limits of porosity, permeability, and gas saturation. After the comprehensive analysis, the lower limits of petrophysical parameters of the Upper Paleozoic tight sandstone gas reservoirs in Ordos Basin are thought as follows: the minimum flow pore throat radius is 0.02 μm, the lower limits of porosity are 3%, the permeability is 0.02 × 10−3 μm2 and the gas saturation is 20%. Besides, the influence of formation pressure on porosity and permeability, the tight sandstone gas filling mechanism, and reservoir characterization petrophysical parameters of tight sandstone reservoirs are further discussed.

  2. 49 CFR 230.72 - Testing main reservoirs. (United States)


    ... the tensile strength of steel is unknown; and R = Inside radius of the reservoir in inches. (2... = certified working pressure in psi; S = 1/5 of the minimum specified tensile strength of the material in psi... strength of the material in psi, or 10,000 psi if the tensile strength is unknown; and R = Inside radius of...

  3. Depth limit of littoral vegetation in a storage reservoir: A case study of Lipno Reservoir (Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    Krolová, M.; Čížková, Hana; Hejzlar, Josef


    Roč. 42, č. 2 (2012), s. 165-174 ISSN 0075-9511 R&D Projects: GA ČR(CZ) GA206/09/1764 EU Projects: European Commission(XE) 244121 - REFRESH Institutional research plan: CEZ:AV0Z60170517; CEZ:AV0Z60870520 Keywords : macrophyte * littoral * reservoir * shore erosion * ecological potential * European Water Framework Directive Subject RIV: DA - Hydrology ; Limnology Impact factor: 1.565, year: 2012

  4. Recognizing limitations in eddy current testing

    International Nuclear Information System (INIS)

    Van Drunen, G.; Cecco, V.S.


    This paper addresses known limitations and constraints in eddy current nondestructive testing. Incomplete appreciation for eddy current limitations is believed to have contributed to both under-utilization and misapplication of the technique. Neither situation need arise if known limitations are recognized. Some, such as the skin depth effect, are inherent to electromagnetic test methods and define the role of eddy current testing. Others can be overcome with available technology such as surface probes to find circumferential cracks in tubes and magnetic saturation of ferromagnetic alloys to eliminate permeability effects. The variables responsible for limitations in eddy current testing are discussed and where alternative approaches exist, these are presented. Areas with potential for further research and development are also identified

  5. Analysis of formation pressure test results in the Mount Elbert methane hydrate reservoir through numerical simulation (United States)

    Kurihara, M.; Sato, A.; Funatsu, K.; Ouchi, H.; Masuda, Y.; Narita, H.; Collett, T.S.


    Targeting the methane hydrate (MH) bearing units C and D at the Mount Elbert prospect on the Alaska North Slope, four MDT (Modular Dynamic Formation Tester) tests were conducted in February 2007. The C2 MDT test was selected for history matching simulation in the MH Simulator Code Comparison Study. Through history matching simulation, the physical and chemical properties of the unit C were adjusted, which suggested the most likely reservoir properties of this unit. Based on these properties thus tuned, the numerical models replicating "Mount Elbert C2 zone like reservoir" "PBU L-Pad like reservoir" and "PBU L-Pad down dip like reservoir" were constructed. The long term production performances of wells in these reservoirs were then forecasted assuming the MH dissociation and production by the methods of depressurization, combination of depressurization and wellbore heating, and hot water huff and puff. The predicted cumulative gas production ranges from 2.16??106m3/well to 8.22??108m3/well depending mainly on the initial temperature of the reservoir and on the production method.This paper describes the details of modeling and history matching simulation. This paper also presents the results of the examinations on the effects of reservoir properties on MH dissociation and production performances under the application of the depressurization and thermal methods. ?? 2010 Elsevier Ltd.

  6. Spatial and temporal variations in fish assemblage: testing the zonation concept in small reservoirs. (United States)

    Baumgartner, M T; Baumgartner, G; Gomes, L C


    Large reservoirs usually present spatial gradients in fish assemblage, distinguishing three strata (littoral, pelagic, and bathypelagic) along the vertical and horizontal axes, and three zones (fluvial, transitional, and lacustrine) along the longitudinal axis. The main objective of this study was to assess if small reservoirs also present the spatial gradients in fish assemblage attributes and structure as already observed in large reservoirs. Fish surveys were conducted quarterly, from 2003 to 2008, in the Mourão Reservoir (Mourão River, Paraná, Brazil), using gillnets with different mesh sizes, arranged in all strata of all three zones. Community attributes (species richness and evenness) were calculated for each sample, and differences were tested using three-way ANOVA (factors: zone, strata, year). Community composition was summarized using Correspondence Analysis (CA) and differences were tested with three-way ANOVA for each axis, controlling the same three factors. Because of the high variability in reservoir water level through time, all analyses were made considering temporal variations. Species richness presented a decreasing trend from fluvial to lacustrine zones, and higher values in littoral strata, possibly because upper reaches and littoral regions provide better conditions for fish to feed and to reproduce. Evenness was considerably low, presenting high variability, and no evident pattern. The expected longitudinal gradient was not found in this study indicating longitudinal similarity, contrary to observed in large reservoirs. Vertical and horizontal gradients were observed in all sampling stations, indicating that abiotic and biotic conditions are influencing fish distributions within the reservoir.

  7. Reservoir evaluation tests on RRGE 1 and RRGE 2, Raft River Geothermal Project, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Narasimhan, T.N.; Witherspoon, P.A.


    Results of the production and interference tests conducted on the geothermal wells RRGE 1 and RRGE 2 in Raft River Valley, Idaho during September--November, 1975 are presented. In all, three tests were conducted, two of them being short-duration production tests and one, a long duration interference test. In addition to providing estimates on the permeability and storage parameters of the geothermal reservoir, the tests also indicated the possible existence of barrier boundaries. The data collected during the tests also indicated that the reservoir pressure varies systematically in response to the changes in the Earth's gravitational field caused by the passage of the sun and the moon. Overall, the results of the tests indicate that the geothermal reservoir in southern Raft River valley is fairly extensive and significantly permeable and merits further exploration.

  8. A simplified approach to well test analysis of naturally fractured reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Aguilera, R. [Servipetrol Ltd., Calgary, AB (Canada)


    This paper presents a simplified equation for drawdown and well test analysis of naturally fractured reservoirs. It can also be used for conventional single porosity reservoirs. The proposed technique allows approximate solutions to determine parameters such as fracture, permeability, wellbore storage, skin, storativity ratio, interporosity flow coefficient, fracture spacing, number of fractures intercepted by the wellbore and the amount of secondary mineralization within fractures. The results are in reasonable agreement with more rigorous methods published in the literature which require specialized software. The proposed method was illustrated with actual data from fractured reservoirs. 13 refs., 2 tabs., 4 figs.

  9. Field Characterization of Reservoir Flow Paths Using Miscible and Immiscible Tracer Tests


    Trautz, Robert C.; Freifeld, Barry M.; Doughty, Christine; Benson, Sally M.; Phelps, Tommy J.; McCallum, Scott D.


    Injection of supercritical CO2 into deep, brine-filled reservoirs may be used to slow the effect that greenhouse gas emissions have on global warming. During injection, the large contrast in fluid densities and viscosities causes immiscible displacement of the brine by CO2, resulting in a two-phase system. We performed a series of tracer tests during the Frio CO2 sequestration pilot program to study immiscible and miscible fluid displacement through the Frio sandstone, a deep saline reservoir...

  10. Nuclear Weapon Testing Limitations and International Security (United States)

    Corden, Pierce S.


    For over 50 years stopping nuclear weapon tests has been sought to support achieving international security without nuclear weapons. Testing is the critical path beyond primitive fission devices, e.g. to develop thermonuclear weapons, reduce weight and volume and increase yield. The 1958 Geneva Conference of Experts considered ways to verify a test ban. With then-limitations on seismology, and lack of in-country monitoring and on-site inspections, the 1963 Limited Test Ban Treaty prohibits testing only in the atmosphere, outer space and under water, and is verified by National Technical Means. The US and USSR agreed to a limit of 150 kilotons on underground explosions in the 1970s-80s. The 1996 Comprehensive Nuclear-Test-Ban Treaty bans all nuclear explosions. Its International Monitoring System - seismic, hydroacoustic, infrasound and radionuclide sensors - is being used, and has easily detected testing by the DPRK. On-site inspections will be available under an in-force Treaty. A 2012 National Academy report concludes that cheating attempts would not undermine U.S. security, and the program for monitoring and extending the life of US weapons has succeeded since US testing ceased in 1992.

  11. Investigation of diffusivity coefficient of Asmari reservoir by well test analysis

    Energy Technology Data Exchange (ETDEWEB)

    Shadizadeh, S.R. [Petroleum Univ. of Technology, Tehran (Iran, Islamic Republic of); Amiri, M.; Zaferanieh, M. [National Iranian Oil Co., Tehran (Iran, Islamic Republic of)


    One of the greatest challenges facing petroleum engineers is to characterize the physical nature of subterranean reservoirs from which crude oil is produced. The quality of reservoir description determines the results of numerical simulations of reservoir performance. The ways by which information can be obtained include seismic and geological studies; well drilling data; well pressure testing; and analysis of reservoir performance through history matching. This paper presented the results of a study in which the Asmari field in southern onshore Iran was characterized. The field went into production in 1970. To date, a total of 39 wells have been completed in the Asmari and Bangestan groups of this field. Pan System software was used in this study to analyze the well test data. Parameters such as permeability, skin factor, wellbore storage, average reservoir pressure, diffusivity coefficient and productivity index are calculated for each well. In particular, the diffusivity coefficient for the Asmari sedimentary layer was determined. This dimensionless reservoir parameter is a ratio of a medium's capacity for transmissibility of fluid to capacity. Diffusivity offers a quantitative measure for the rate of response during transient fluid flow. All available information such as petrophysical data, PVT data, production data and pressure build up data of the completed wells in Asmari formation were collected. Twenty one data tests were then analyzed. A correlation between productivity index and the diffusivity coefficient for the Asmari formation was subsequently obtained. It was concluded that permeability is one of the most important parameter in reservoir engineering calculations. Different completion of well number 1 showed that the diffusivity coefficient and productivity index of carbonate layer is less than in the sandstone layer. It was determined that the western part of the reservoir is suitable for drilling new wells.13 refs., 5 tabs., 7 figs.

  12. A new method of well test analysis in naturally fractured reservoirs based on elliptical flow

    Energy Technology Data Exchange (ETDEWEB)

    Igbokoyi, A.O.; Tiab, D. [Oklahoma Univ., Norman, OK (United States)


    Well testing analysis in naturally fractured reservoirs is usually based on the radial flow model. However, this model is only applicable to purely homogeneous system and long time solution and cannot provide complete formation analysis in a reservoir that exhibits anisotropy. This paper presented a new method of estimating permeability anisotropy in naturally fractured reservoirs. Maximum and minimum permeability were obtained in one well test. The paper discussed the mathematical formulation for the study which used Warren and Root's matrix pseudo-steady state model. The paper presented the assumptions for this model which included an isotropic homogeneous or anisotropic homogeneous formation; a slightly compressible fluid with single phase flow in both the matrix and fracture; initial reservoir pressure; two-dimensional flow; and laminar flow which obeys Darcy's law. The paper also discussed the computation of wellbore pressure and interpretation methods for both early linear flow and the long time radial flow regimes. Anisotropy was also outlined as the purpose of the study was to use an elliptical flow model in quantifying the permeability anisotropy of the reservoir. The type curve model was also explained to demonstrate the validity of the method of quantifying the permeability anisotropy with a known problem. Last, the paper explained the direct method with several example. It was concluded that the elliptical flow model is the most appropriate method of analyzing pressure transient data in naturally fractured reservoirs. 22 refs., 5 tabs., 15 figs., 3 appendices.

  13. Testing geopressured geothermal reservoirs in existing wells. Annual report

    Energy Technology Data Exchange (ETDEWEB)


    This contract called for the acquisition and testing of Wells of Opportunity. Wells of Opportunity are located by screening published information on oil industry activity and through personal contacts with oil operators. This process resulted in recommendation of 21 candidate wells to the DOE for the WOO program. Of the 21 wells recommended, 7 were accepted. Six of these 7 were acquired for testing. Three wells have been tested, and the fourth and fifth will be tested early in 1981. Preliminary test results are briefly described and are shown in a table. The actual testing schedule and the originally proposed schedule matched very closely. Cumulative costs through November 1980 were approximately $6.5 million and compare to an estimate of $8.5 million for the same period. A graphical comparison of actual versus estimated costs is given.

  14. Spatial and temporal variations in fish assemblage: testing the zonation concept in small reservoirs

    Directory of Open Access Journals (Sweden)

    M. T. Baumgartner


    Full Text Available Abstract Large reservoirs usually present spatial gradients in fish assemblage, distinguishing three strata (littoral, pelagic, and bathypelagic along the vertical and horizontal axes, and three zones (fluvial, transitional, and lacustrine along the longitudinal axis. The main objective of this study was to assess if small reservoirs also present the spatial gradients in fish assemblage attributes and structure as already observed in large reservoirs. Fish surveys were conducted quarterly, from 2003 to 2008, in the Mourão Reservoir (Mourão River, Paraná, Brazil, using gillnets with different mesh sizes, arranged in all strata of all three zones. Community attributes (species richness and evenness were calculated for each sample, and differences were tested using three-way ANOVA (factors: zone, strata, year. Community composition was summarized using Correspondence Analysis (CA and differences were tested with three-way ANOVA for each axis, controlling the same three factors. Because of the high variability in reservoir water level through time, all analyses were made considering temporal variations. Species richness presented a decreasing trend from fluvial to lacustrine zones, and higher values in littoral strata, possibly because upper reaches and littoral regions provide better conditions for fish to feed and to reproduce. Evenness was considerably low, presenting high variability, and no evident pattern. The expected longitudinal gradient was not found in this study indicating longitudinal similarity, contrary to observed in large reservoirs. Vertical and horizontal gradients were observed in all sampling stations, indicating that abiotic and biotic conditions are influencing fish distributions within the reservoir.

  15. Genotoxicity assessment of water sampled from R-11 reservoir by means of allium test

    Energy Technology Data Exchange (ETDEWEB)

    Bukatich, E.; Pryakhin, E. [Urals Research Center for Radiation Medicine (Russian Federation); Geraskin, S. [Russian Institute of Agricultural Radiology and Agroecology (Russian Federation)


    The Mayak PA was the first enterprise for the production of weapon-grade plutonium in Russia and it incorporates uranium-graphite reactors for plutonium production and radiochemical facilities for its separation. Radiochemical processing resulted in huge volumes of liquid radioactive wastes of different specific activities. To reduce the radionuclides release into the environment, a system of bypasses and ponds (the Techa Cascade Reservoirs system) to store low-activity liquid wastes has been constructed in the upper reaches of the Techa River. Currently, industrial reservoirs of Mayak PA contain over 350 million m{sup 3} of low-level radioactive liquid wastes with total activity over 7.4 x 10{sup 15} Bq. Reservoir R-11 is the final reservoir in the Techa Cascade Reservoirs system. The average specific activity of main radionuclides in the water of R-11 are: {sup 90}Sr - 1.4x10{sup 3} Bq/l; {sup 137}Cs - 3 Bq/l; {sup 3}H - 7x10{sup 2} Bq/l; α-emitting radionuclides - 2.6 x 10{sup -1} Bq/l. In our study the Allium-test was employed to estimate reservoir R-11 water genotoxic effects. In 2012, 3 water samples were collected in different parts of reservoir R-11. Water samples from the Shershnevskoye reservoir (artificial reservoir on the Miass River designed for Chelyabinsk city water supply) were used as natural control. Samples of distilled and bottled water were used as an additional laboratory control. The common onion, Allium cepa L. (Stuttgarter Riesen) was used. Healthy equal-sized bulbs were soaked for 24 hours at +4±2 deg. C to synchronize cell division. The bulbs were maintained in distilled water at +23 deg. C until roots have grown up to 2±1 mm length and then plunged into water samples. Control samples remained in distilled and bottled water as well as in water samples from the Shershnevskoye reservoir (natural control). Roots of the 18±3 mm length were randomly sampled and fixed in an alcohol/acetic acid mixture. For microscopic analysis, squashed

  16. Structural and Conservation Effort Alternatives to Extending Jatigede Reservoir Service Lifetime by Limiting Sedimentation (United States)

    Rohmat, F. I.; Hadihardaja, I. K.; Rohmat, D.


    Jatigede Reservoir, which is being constructed in West Java province, Indonesia, is planned to begin operation in late 2013. It is designed to provide 90,000 ha of paddy field irrigation, 100 MW power generation, and flood control. However, previous studies indicate that the reservoir will only have a service life of 7 to 30 years, rather than its 100-year design service life. One reason is the high rate of sedimentation, which is predicted to reach more than 8 million tons per year because of changes in land use in the watershed. This condition is aggravated by the removal of the flushing gate on the bottom of the dam. This study examines alternatives to extend the service life of Jatigede Reservoir, including a structural solution (extending and raising the irrigation inlet to increase the dead storage), watershed conservation, and a combination of these alternatives. The structural effort may extend the reservoir's service life by 10 to 20 years, but with considerable effect on increasing flooding and drought risk by reduced live storage. Structural options need to be combined with conservation options in order to extend the service life of Jatigede Reservoir to the desired range.

  17. Formation evaluation and well-test analysis for complex interpretation of reservoir permeability distribution (United States)

    Korovin, M. O.; Merkulov, V. P.


    Data on heterogeneity of porous space and reservoir filtration properties determines the choice of most effective development strategy. The comparative analysis of well-logging and well-test results was carried out to determine the value of filtration heterogeneity. The similarity of the results obtained using different methods makes it possible to predict orientation of enhanced permeability.

  18. Using outcrop data for geological well test modelling in fractured reservoirs

    NARCIS (Netherlands)

    Aljuboori, F.; Corbett, P.; Bisdom, K.; Bertotti, G.; Geiger, S.


    Outcrop fracture data sets can now be acquired with ever more accuracy using drone technology augmented by field observations. These models can be used to form realistic, deterministic models of fractured reservoirs. Fractured well test models are traditionally seen to be finite or infinite

  19. Superposition well-test method for reservoir characterization and pressure management during CO2 injection (United States)

    White, J. A.


    As a significant fraction of a carbon storage project's budget is devoted to site characterization and monitoring, there has been an intense drive in recent years to both lower cost and improve the quality of data obtained. Two data streams that are cheap and always available are pressure and flow rate measurements from the injection well. Falloff testing, in which the well is shut-in for some period of time and the pressure decline curve measured, is often used to probe the storage zone and look for indications of hydraulic barriers, fracture-dominated flow, and other reservoir characteristics. These tests can be used to monitor many hydromechanical processes of interest, including hydraulic fracturing and fault reactivation. Unfortunately, the length of the shut-in period controls how far away from the injector information may be obtained. For operational reasons these tests are typically kept short and infrequent, limiting their usefulness. In this work, we present a new analysis method in which ongoing injection data is used to reconstruct an equivalent falloff test, without shutting in the well. The entire history of injection may therefore be used as a stand in for a very long test. The method relies upon a simple superposition principle to transform a multi-rate injection sequence into an equivalent single-rate process. We demonstrate the effectiveness of the method using injection data from the Snøhvit storage project. We also explore its utility in an active pressure management scenario. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  20. Dynamic tests on metallic impact limiters

    International Nuclear Information System (INIS)

    Sagartz, M.J.


    Three different types of metallic impact limiters were tested; plain fins, laterally stiffened fins and tubes whose axes were aligned with the direction of impact. All specimens were made of 304 stainless steel and were annealed before testing. A heavy steel drop table of variable mass and moving at about 13.4 m/s (44 ft/s) was used to impact the specimens which were mounted on a stationary base. Impact velocity, drop table acceleration vs. time and force vs. time were measured on each test and were used to calculate the energy absorbed by the impact limiters. Results showed that the peak stress that a plain fin can transmit to the cask body can be several times the static yield stress of the fin. Also as buckling proceeds the load in a plain fin drops significantly and the rate at which it absorbs energy falls off dramatically, making the fin a rather inefficient energy absorber overall. The laterally stiffened fin and the cylinders did not exhibit this rapid decrease in load-carrying capacity with deformation and hence were able to absorb relatively more energy per unit volume of material

  1. Simulation of water-energy fluxes through small-scale reservoir systems under limited data availability (United States)

    Papoulakos, Konstantinos; Pollakis, Giorgos; Moustakis, Yiannis; Markopoulos, Apostolis; Iliopoulou, Theano; Dimitriadis, Panayiotis; Koutsoyiannis, Demetris; Efstratiadis, Andreas


    Small islands are regarded as promising areas for developing hybrid water-energy systems that combine multiple sources of renewable energy with pumped-storage facilities. Essential element of such systems is the water storage component (reservoir), which implements both flow and energy regulations. Apparently, the representation of the overall water-energy management problem requires the simulation of the operation of the reservoir system, which in turn requires a faithful estimation of water inflows and demands of water and energy. Yet, in small-scale reservoir systems, this task in far from straightforward, since both the availability and accuracy of associated information is generally very poor. For, in contrast to large-scale reservoir systems, for which it is quite easy to find systematic and reliable hydrological data, in the case of small systems such data may be minor or even totally missing. The stochastic approach is the unique means to account for input data uncertainties within the combined water-energy management problem. Using as example the Livadi reservoir, which is the pumped storage component of the small Aegean island of Astypalaia, Greece, we provide a simulation framework, comprising: (a) a stochastic model for generating synthetic rainfall and temperature time series; (b) a stochastic rainfall-runoff model, whose parameters cannot be inferred through calibration and, thus, they are represented as correlated random variables; (c) a stochastic model for estimating water supply and irrigation demands, based on simulated temperature and soil moisture, and (d) a daily operation model of the reservoir system, providing stochastic forecasts of water and energy outflows. Acknowledgement: This research is conducted within the frame of the undergraduate course "Stochastic Methods in Water Resources" of the National Technical University of Athens (NTUA). The School of Civil Engineering of NTUA provided moral support for the participation of the students

  2. A study of well test data interpretation model for waterbearing reservoirs with phase redistribution (United States)

    Zhang, Junxiang; Deng, Rui; Liang, Haipeng; Yang, Jing


    In China, plentiful marine reservoirs exist. Net pay thickness in individual gas reservoirs where partial penetration was performed can be hundreds of meters. Due to the influence of condensate water and formation, water phase separation phenomenon, where gas rose up and liquid moved down, and a morsel of water production emerged in some gas wells, which makes the build-up curves distorted and thus unable to be interpreted. On the basis of seepage theory and Laplace transformation, a seepage mathematical model and a well test interpretation model for gas wells with phase separation considered are developed to analyze the impact of such various elements as phase separation and partial penetration on the pressure and pressure derivative log-log plot. With practical data of well test in Xihu Sag, reliability analysis of the mathematical model mentioned above was demonstrated. Theoretical research results proposed in our study substantially improved the accuracy of well test interpretation for thick water-bearing gas reservoirs and laid a technical foundation of development of the similar oil & gas reservoirs.

  3. Tracer tests on furnaces at Metalloys Limited

    International Nuclear Information System (INIS)

    Smith, D.J.; Wedepohl, A.


    During 1980, thirteen double tests were carried out with five radioactive isotopes on three furnaces at Metalloys Limited, near Meyerton. Each double test involved the introduction of a sample of coke impregnated with lanthanum and a sample of irradiated manganese ore ( 54 Mn or 59 Fe), irradiated quartzite ( 46 Sc), or irradiated coal ( 46 Sc, 59 Fe, and 60 Co). The tests were conducted on the three large furnaces for the production of high-carbon ferromanganese, viz M10, M11, and M12. The radioactivity of samples of the metal and the slag leaving the furnace was measured by the Isotopes and Activation Division of the Atomic Energy Board (AEB). Response curves and computer analyses are presented on the elution of the tracers from the furnaces. The response curves for the tracers, which were inserted close to the electrodes, are discussed so that the salient differences between their passage through the three furnaces can be established. The results obtained give support to the findings of a dig-out carried out on furnace M10 during 1977. The metal and slag products of furnace M12 were subjected to mineralogical investigation so that the major phases in the furnace products could be determined. Details of the calculation of the mean residence time for material in furnace M12 are given in an appendix

  4. Water-rock interaction in CO2 sequestration in a depleted oil reservoir pilot test

    International Nuclear Information System (INIS)

    Pang, Zhonghe; Kong, Yanlong; Li, Yiman; Li, Jie


    A field test of CO 2 sequestration in the Neogene Minghuazhen Formation in the Bohai Bay Basin (BBB-Nm test) is presented, where the first Chinese pilot project of CO 2 storage in a depleted oil reservoir was implemented. A total of 305 t CO 2 was injected into the sandstone reservoir. The process of injection and pre/post-injection monitoring are described, especially for the geochemical monitoring in the field test. Results show that CO 2 flux monitoring successfully tracked the injected CO 2 . Chemical analyses of post-injection brine samples indicate brine may have not been affected by CO 2 injection during the monitoring period, which needs to be confirmed with further investigations before extending the results to deep saline aquifers. (authors)

  5. Testing geopressured geothermal reservoirs in existing wells. Final report P. R. Girouard Well No. 1, Lafayette Parish, Louisiana. Volume I. Completion and testing

    Energy Technology Data Exchange (ETDEWEB)


    The P.R. Girouard No. 1 Well, located approximately 10 miles southeast of Lafayette, Louisiana, was the fourth successful test of a geopressured-geothermal aquifer under the Wells of Opportunity program. The well was tested through 3-1/2 inch tubing set on a packer at 14,570 feet without major problems. The geological section tested was the Oligocene Marginulina Texana No. 1 sand of upper Frio age. The interval tested was from 14,744 to 14,819 feet. Produced water was piped down a disposal well perforated from 2870 to 3000 feet in a Miocene saltwater sand. Four flow tests were conducted for sustained production rates of approximately 4000 BWPD to approximately 15,000 BWPD. The highest achieved, during a fifth short test, was 18,460 BWPD. The test equipment was capable of handling higher rates. The gas-to-water ratio was relatively uniform at approximately 40 SCF/bbl. The heating value of the gas is 970 Btu/SCF. The reservoir tests show that is is doubtful that this well would sustain production rates over 10,000 BWPD for any lengthy period from the sand zone in which it was completed. This limited flow capacity is due to the well's poor location in the reservoir and is not a result of any production deficiencies of the Marginulina Texana sand.

  6. Reservoir characterization and final pre-test analysis in support of the compressed-air-energy-storage Pittsfield aquifer field test in Pike County, Illinois

    Energy Technology Data Exchange (ETDEWEB)

    Wiles, L.E.; McCann, R.A.


    The work reported is part of a field experimental program to demonstrate and evaluate compressed air energy storage in a porous media aquifer reservoir near Pittsfield, Illinois. The reservoir is described. Numerical modeling of the reservoir was performed concurrently with site development. The numerical models were applied to predict the thermohydraulic performance of the porous media reservoir. This reservoir characterization and pre-test analysis made use of evaluation of bubble development, water coning, thermal development, and near-wellbore desaturation. The work was undertaken to define the time required to develop an air storage bubble of adequate size, to assess the specification of instrumentation and above-ground equipment, and to develop and evaluate operational strategies for air cycling. A parametric analysis was performed for the field test reservoir. (LEW)

  7. Characterizing hydraulic fractures in shale gas reservoirs using transient pressure tests

    Directory of Open Access Journals (Sweden)

    Cong Wang


    This work presents an unconventional gas reservoir simulator and its application to quantify hydraulic fractures in shale gas reservoirs using transient pressure data. The numerical model incorporates most known physical processes for gas production from unconventional reservoirs, including two-phase flow of liquid and gas, Klinkenberg effect, non-Darcy flow, and nonlinear adsorption. In addition, the model is able to handle various types and scales of fractures or heterogeneity using continuum, discrete or hybrid modeling approaches under different well production conditions of varying rate or pressure. Our modeling studies indicate that the most sensitive parameter of hydraulic fractures to early transient gas flow through extremely low permeability rock is actually the fracture-matrix contacting area, generated by fracturing stimulation. Based on this observation, it is possible to use transient pressure testing data to estimate the area of fractures generated from fracturing operations. We will conduct a series of modeling studies and present a methodology using typical transient pressure responses, simulated by the numerical model, to estimate fracture areas created or to quantity hydraulic fractures with traditional well testing technology. The type curves of pressure transients from this study can be used to quantify hydraulic fractures in field application.

  8. Testing the limits of gradient sensing.

    Directory of Open Access Journals (Sweden)

    Vinal Lakhani


    Full Text Available The ability to detect a chemical gradient is fundamental to many cellular processes. In multicellular organisms gradient sensing plays an important role in many physiological processes such as wound healing and development. Unicellular organisms use gradient sensing to move (chemotaxis or grow (chemotropism towards a favorable environment. Some cells are capable of detecting extremely shallow gradients, even in the presence of significant molecular-level noise. For example, yeast have been reported to detect pheromone gradients as shallow as 0.1 nM/μm. Noise reduction mechanisms, such as time-averaging and the internalization of pheromone molecules, have been proposed to explain how yeast cells filter fluctuations and detect shallow gradients. Here, we use a Particle-Based Reaction-Diffusion model of ligand-receptor dynamics to test the effectiveness of these mechanisms and to determine the limits of gradient sensing. In particular, we develop novel simulation methods for establishing chemical gradients that not only allow us to study gradient sensing under steady-state conditions, but also take into account transient effects as the gradient forms. Based on reported measurements of reaction rates, our results indicate neither time-averaging nor receptor endocytosis significantly improves the cell's accuracy in detecting gradients over time scales associated with the initiation of polarized growth. Additionally, our results demonstrate the physical barrier of the cell membrane sharpens chemical gradients across the cell. While our studies are motivated by the mating response of yeast, we believe our results and simulation methods will find applications in many different contexts.

  9. Predicting the natural state of fractured carbonate reservoirs: An Andector Field, West Texas test of a 3-D RTM simulator

    Energy Technology Data Exchange (ETDEWEB)

    Tuncay, K.; Romer, S.; Ortoleva, P. [Indiana Univ., Bloomington, IN (United States); Hoak, T. [Kestrel Geoscience, Littleton, CO (United States); Sundberg, K. [Phillips Petroleum Co., Bartlesville, OK (United States)


    The power of the reaction, transport, mechanical (RTM) modeling approach is that it directly uses the laws of geochemistry and geophysics to extrapolate fracture and other characteristics from the borehole or surface to the reservoir interior. The objectives of this facet of the project were to refine and test the viability of the basin/reservoir forward modeling approach to address fractured reservoir in E and P problems. The study attempts to resolve the following issues: role of fracturing and timing on present day location and characteristics; clarifying the roles and interplay of flexure dynamics, changing rock rheological properties, fluid pressuring and tectonic/thermal histories on present day reservoir location and characteristics; and test the integrated RTM modeling/geological data approach on a carbonate reservoir. Sedimentary, thermal and tectonic data from Andector Field, West Texas, were used as input to the RTM basin/reservoir simulator to predict its preproduction state. The results were compared with data from producing reservoirs to test the RTM modeling approach. The effects of production on the state of the field are discussed in a companion report. The authors draw the following conclusions: RTM modeling is an important new tool in fractured reservoir E and P analysis; the strong coupling of RTM processes and the geometric and tensorial complexity of fluid flow and stresses require the type of fully coupled, 3-D RTM model for fracture analysis as pioneered in this project; flexure analysis cannot predict key aspects of fractured reservoir location and characteristics; fracture history over the lifetime of a basin is required to understand the timing of petroleum expulsion and migration and the retention properties of putative reservoirs.

  10. Testing geopressured geothermal reservoirs in existing wells. Final report P. R. Girouard Well No. 1, Lafayette Parish, Louisiana. Volume II. Well test data

    Energy Technology Data Exchange (ETDEWEB)


    The following data from the reopening of an abandoned well are presented: reservoir pressure drawdown and buildup data, Institute of Gas Technology test data, Insitute of Gas Technology sample log, reservoir fluid analysis, produced gas/water ratio, chemical analysis procedures, surface flow data, third party sampling and reports, sand detectors charts, and Horner-type buildup data. (MHR)

  11. Numerical Well Testing Interpretation Model and Applications in Crossflow Double-Layer Reservoirs by Polymer Flooding

    Directory of Open Access Journals (Sweden)

    Haiyang Yu


    Full Text Available This work presents numerical well testing interpretation model and analysis techniques to evaluate formation by using pressure transient data acquired with logging tools in crossflow double-layer reservoirs by polymer flooding. A well testing model is established based on rheology experiments and by considering shear, diffusion, convection, inaccessible pore volume (IPV, permeability reduction, wellbore storage effect, and skin factors. The type curves were then developed based on this model, and parameter sensitivity is analyzed. Our research shows that the type curves have five segments with different flow status: (I wellbore storage section, (II intermediate flow section (transient section, (III mid-radial flow section, (IV crossflow section (from low permeability layer to high permeability layer, and (V systematic radial flow section. The polymer flooding field tests prove that our model can accurately determine formation parameters in crossflow double-layer reservoirs by polymer flooding. Moreover, formation damage caused by polymer flooding can also be evaluated by comparison of the interpreted permeability with initial layered permeability before polymer flooding. Comparison of the analysis of numerical solution based on flow mechanism with observed polymer flooding field test data highlights the potential for the application of this interpretation method in formation evaluation and enhanced oil recovery (EOR.

  12. Implications of Limited Thermophilicity of Nitrite Reduction for Control of Sulfide Production in Oil Reservoirs (United States)

    Fida, Tekle Tafese; Chen, Chuan; Okpala, Gloria


    ABSTRACT Nitrate reduction to nitrite in oil fields appears to be more thermophilic than the subsequent reduction of nitrite. Concentrated microbial consortia from oil fields reduced both nitrate and nitrite at 40 and 45°C but only nitrate at and above 50°C. The abundance of the nirS gene correlated with mesophilic nitrite reduction activity. Thauera and Pseudomonas were the dominant mesophilic nitrate-reducing bacteria (mNRB), whereas Petrobacter and Geobacillus were the dominant thermophilic NRB (tNRB) in these consortia. The mNRB Thauera sp. strain TK001, isolated in this study, reduced nitrate and nitrite at 40 and 45°C but not at 50°C, whereas the tNRB Petrobacter sp. strain TK002 and Geobacillus sp. strain TK003 reduced nitrate to nitrite but did not reduce nitrite further from 50 to 70°C. Testing of 12 deposited pure cultures of tNRB with 4 electron donors indicated reduction of nitrate in 40 of 48 and reduction of nitrite in only 9 of 48 incubations. Nitrate is injected into high-temperature oil fields to prevent sulfide formation (souring) by sulfate-reducing bacteria (SRB), which are strongly inhibited by nitrite. Injection of cold seawater to produce oil creates mesothermic zones. Our results suggest that preventing the temperature of these zones from dropping below 50°C will limit the reduction of nitrite, allowing more effective souring control. IMPORTANCE Nitrite can accumulate at temperatures of 50 to 70°C, because nitrate reduction extends to higher temperatures than the subsequent reduction of nitrite. This is important for understanding the fundamentals of thermophilicity and for the control of souring in oil fields catalyzed by SRB, which are strongly inhibited by nitrite. PMID:27208132

  13. Two-phase flow in volatile oil reservoir using two-phase pseudo-pressure well test method

    Energy Technology Data Exchange (ETDEWEB)

    Sharifi, M.; Ahmadi, M. [Calgary Univ., AB (Canada)


    A study was conducted to better understand the behaviour of volatile oil reservoirs. Retrograde condensation occurs in gas-condensate reservoirs when the flowing bottomhole pressure (BHP) lowers below the dewpoint pressure, thus creating 4 regions in the reservoir with different liquid saturations. Similarly, when the BHP of volatile oil reservoirs falls below the bubblepoint pressure, two phases are created in the region around the wellbore, and a single phase (oil) appears in regions away from the well. In turn, higher gas saturation causes the oil relative permeability to decrease towards the near-wellbore region. Reservoir compositional simulations were used in this study to predict the fluid behaviour below the bubblepoint. The flowing bottomhole pressure was then exported to a well test package to diagnose the occurrence of different mobility regions. The study also investigated the use of a two-phase pseudo-pressure method on volatile and highly volatile oil reservoirs. It was concluded that this method can successfully predict the true permeability and mechanical skin. It can also distinguish between mechanical skin and condensate bank skin. As such, the two-phase pseudo-pressure method is particularly useful for developing after-drilling well treatment and enhanced oil recovery process designs. However, accurate relative permeability and PVT data must be available for reliable interpretation of the well test in volatile oil reservoirs. 18 refs., 3 tabs., 9 figs.

  14. Reconciling longwall gob gas reservoirs and venthole production performances using multiple rate drawdown well test analysis

    Energy Technology Data Exchange (ETDEWEB)

    Karacan, C. Oezgen [National Institute for Occupational Safety and Health (NIOSH), Pittsburgh Research Laboratory, Pittsburgh 15236, PA (United States)


    Longwall mining is an underground mining method during which a mechanical shearer progressively mines a large block of coal, called a panel, in an extensive area. During this operation the roof of the coal seam is supported only temporarily with hydraulic supports that protect the workers and the equipment on the coal face. As the coal is extracted, the supports automatically advance and the roof strata cave behind the supports. Caving results in fracturing and relaxation of the overlying strata, which is called ''gob.'' Due its highly fractured nature, gob contains many flow paths for gas migration. Thus, if the overlying strata contain gassy sandstones or sandstone channels, gas shales or thinner coal seams which are not suitable for mining, then the mining-induced changes can cause unexpected or uncontrolled gas migration into the underground workplace. Vertical gob gas ventholes (GGV) are drilled into each longwall panel to capture the methane within the overlying fractured strata before it enters the work environment. Thus, it is important, first to understand the properties of the gas reservoir created by mining disturbances and, second, to optimize the well parameters and placement accordingly. In this paper, the production rate-pressure behaviors of six GGVs drilled over three adjacent panels were analyzed by using conventional multi-rate drawdown analysis techniques. The analyses were performed for infinite acting and pseudo-steady state flow models, which may be applicable during panel mining (DM) and after mining (AM) production periods of GGVs. These phases were analyzed separately since the reservoir properties, due to dynamic subsidence, boundary conditions and gas capacity of the gob reservoir may change between these two stages. The results suggest that conventional well test analysis techniques can be applicable to highly complex gob reservoirs and GGVs to determine parameters such as skin, permeability, radius of investigation

  15. Decline of clear-water rotifer populations in a reservoir: the role of resource limitation

    Czech Academy of Sciences Publication Activity Database

    Devetter, Miloslav; Seďa, Jaromír


    Roč. 546, č. 1 (2005), s. 509-518 ISSN 0018-8158 Institutional research plan: CEZ:AV0Z60660521 Keywords : resource limitation * rotifers * birth rate Subject RIV: EH - Ecology, Behaviour Impact factor: 0.978, year: 2005

  16. Well test analysis of horizontal wells in a two-layered reservoir ...

    African Journals Online (AJOL)

    reservoir drained from each layer by a horizontal well. Reservoir mathematical model are derived for each layer so that analysis can be done strictly for each layered reservoir. Procedures for obtaining all the directional permeabilities, wellbore skin, degree of crossflow and individual layers average pressures are discussed ...

  17. Tests of US rock salt for long-term stability of CAES reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Gehle, R.M.; Thoms, R.L.


    This is a report on laboratory tests to assess the effects of compressed air energy storage (CAES) on rock salt within the US. The project included a conventional laboratory test phase, with triaxial test machines, and a bench-scale test phase performed in salt mines in southern Louisiana. Limited numerical modeling also was performed to serve as a guide in selecting test layouts and for interpreting test data.

  18. 14 CFR 23.681 - Limit load static tests. (United States)


    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit load static tests. 23.681 Section 23.681 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... Control Systems § 23.681 Limit load static tests. (a) Compliance with the limit load requirements of this...

  19. 14 CFR 25.681 - Limit load static tests. (United States)


    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit load static tests. 25.681 Section 25.681 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... load static tests. (a) Compliance with the limit load requirements of this Part must be shown by tests...

  20. 14 CFR 27.681 - Limit load static tests. (United States)


    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit load static tests. 27.681 Section 27.681 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... static tests. (a) Compliance with the limit load requirements of this part must be shown by tests in...

  1. 14 CFR 29.681 - Limit load static tests. (United States)


    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit load static tests. 29.681 Section 29.681 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... load static tests. (a) Compliance with the limit load requirements of this part must be shown by tests...

  2. On automatic data processing and well-test analysis in real-time reservoir management applications

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, Stig


    The use of pressure and rate sensors for continuous measurements in the oil and gas wells are becoming more common. This provides better and more measurements in real time that can be analyzed to optimize the extraction of oil and gas. An analysis which can provide valuable information on oil and gas production, is transient analysis. In transient analysis pressure build-up in a well when it closed in are analyzed and parameters that describe the flow of oil and gas in the reservoir is estimated. However, it is very time consuming to manage and analyze real-time data and the result is often that only a limited amount of the available data are analyzed. It is therefore desirable to have more effective methods to analyze real time data from oil and gas wells. Olsen automated transient analysis in order to extract the information of real-time data in an efficient and labor-saving manner. The analysis must be initialized with well and reservoir-specific data, but when this is done, the analysis is performed automatically each time the well is closed in. For each shut-in are parameters that describe the flow of oil and gas in the reservoir estimated. By repeated shut, it will then appear time series of estimated parameters. One of the goals of the automated transient analysis lights up is to detect any changes in these time series so that the focus of the engineers can aim on the analysis results that deviate from normal. As part of this work it was also necessary to develop automated data filters for noise removal and data compression. The filter is designed so that it continuously filters the data using methods that are optimized for use on the typical pressure and rate signals measured in the oil and gas wells. The thesis shows Olsen examples of the use of automated data filtering and automated transient analysis of both synthetic data and real data from a field in the North Sea. (AG)

  3. Limits on replenishment of the resting CD4+ T cell reservoir for HIV in patients on HAART.

    Directory of Open Access Journals (Sweden)

    Ahmad R Sedaghat


    Full Text Available Whereas cells productively infected with human immunodeficiency virus type 1 (HIV-1 decay rapidly in the setting of highly active antiretroviral therapy (HAART, latently infected resting CD4(+ T cells decay very slowly, persisting for the lifetime of the patient and thus forming a stable reservoir for HIV-1. It has been suggested that the stability of the latent reservoir is due to low-level viral replication that continuously replenishes the reservoir despite HAART. Here, we offer the first quantitative study to our knowledge of inflow of newly infected cells into the latent reservoir due to viral replication in the setting of HAART. We make use of a previous observation that in some patients on HAART, the residual viremia is dominated by a predominant plasma clone (PPC of HIV-1 not found in the latent reservoir. The unique sequence of the PPC serves as a functional label for new entries into the reservoir. We employ a simple mathematical model for the dynamics of the latent reservoir to constrain the inflow rate to between 0 and as few as 70 cells per day. The magnitude of the maximum daily inflow rate is small compared to the size of the latent reservoir, and therefore any inflow that occurs in patients on HAART is unlikely to significantly influence the decay rate of the reservoir. These results suggest that the stability of the latent reservoir is unlikely to arise from ongoing replication during HAART. Thus, intensification of standard HAART regimens should have minimal effects on the decay of the latent reservoir.

  4. The Impact of Time Limits on Test Behaviors. (United States)

    Lin, Miao-Hsiang

    Specific questions addressed in this study include how time limits affect a test's construct and predictive validities, how time limits affect an examinee's time allocation and test performance, and whether the assumption about how examinees answer items is valid. Interactions involving an examinee's sex and age are studied. Two parallel forms of…

  5. Well test simulation through Discrete Fracture Network modelling in a fractured carbonate reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Casciano, C.; Ruvo, L.; Volpi, B.; Masserano, F.


    A Discrete Fracture Network (DFN) model was used to simulate the results of a production test carried out in a well drilled in a tight, fractured carbonate reservoir. Several static DFN models, depicting different geological scenarios, were built based on data from well logs, core analyses, PLT surveys and structural geology studies. Each of these models underwent a validation procedure, consisting of the simulation of the production test. The comparison between the simulated results and the actual data identified the scenarios whose results most closely matched the actual well behaviour. In order to compensate for the lack of geological data, an iterative loop was performed between the static model and the dynamic simulation. Constraints-added flow simulations provided new information for use in modifying the DFN model, resulting in a step-by-step updating of the static model itself. Finally, a geologically sound model accurately matching the results of the production test was obtained. The final DFN model was used to calculate the equivalent petrophysical parameters that were transferred to the corresponding region of the full field dual-porosity fluid flow model. (author)

  6. Sweet Lake Geopressured-geothermal Project, Magma Gulf-Technadril/DOE Amoco Fee. Volume II. Surface installations reservoir testing. Annual report, February 28, 1981-February 10, 1982

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, K.S. (ed.)


    The Magma Gulf-Technadril/Department of Energy Amoco Fee No. 1 (production) and salt water disposal wells were drilled in the period from August, 1980 to February 1981. Surface facilities were designed and constructed during March-June 1981. Flow testing began in June 1981 and continued until February, 1982. The Miogypsinoides interval contains seven discrete sands in the test well. These sands have been numbered 1 to 7, beginning at the top of the sequence. Data from wireline logs and core samples suggested that the first zone to be perforated should be Sand 5. Because of its high porosity and permeability, Sand 5 was thought to contain almost 50% of the total hydraulic capacity of the well. Flow testing of Sand 5 was performed in three stages, each of which is fully described in this report. Phase I was designed as an initial clean-up flow and a reservoir confirmation test. Phase II consisted of the reservoir limit determination test and lasted 17 days. Boundaries were confirmed which suggest that the Sweet Lake reservoir is fairly narrow, with boundaries on three sides, but is open in one direction with no closure for at least 4-1/4 miles. These boundaries approximate the shape of the graben in which the test well was drilled, but may or may not be directly related to the major faults forming the graben. Phase III testing was planned to be a long-term test at commercial design rates. Although Sand 5 alone would not support such rates, long-term production was demonstrated. Additional research not supported by DOE funding was also performed during the period covered by this report. This research, consisting of mud logging, micropaleontology, organic geochemistry, core analysis, and rock mechanics, is summarized in this report.

  7. Distinct expression of alkaline phosphatase activity in epilimnetic bacteria: Implication for persistent DOC consumption in a P-limited reservoir (United States)

    Tseng, Y.; Kao, S.; Shiah, F.


    In a P-deficient system, P availability usually controls the microbial activity and thus the ecosystem function. Thingstad et al. (1997) first addressed a 'Malfunctioning Microbial-loop' theory, which stated that low bacterial production (BP) caused by insufficient nutrient supply would result in DOC accumulation in an oligotrophic ecosystem. In this study we re-examined the theory by conducting seasonal patterns and correlations among soluble reactive phosphate (SRP) and DOC, microbial abundances (picocyanobacteria, bacteria, and heterotrophic nanoflagellate; HNF) and activities (primary production, bacterial production, and alkaline phosphatase activity; APA) coupled with enzyme-labeled fluorescence (ELF) assays on bacterioplankton in a subtropical reservoir sharing the common features, nitrate-replete and P-deficient, with most natural freshwater system during Oct 2007-Oct 2008. Persistently high APA was recorded during most of time, implying that the system was P-deficient. Size fractionated APA and ELF assay revealed that bacteria were the major APA contributor. However, significantly low epilimnion DOC was recorded during the stratified summer season accompanying with high BP and APA as well as high PP, implying that heterotrophic bacteria can well sustain in P-deficient system by utilizing DOP to rapidly lower down DOC under relatively high PP. Such findings oppose the 'Malfunctioning Microbial-loop' theory. On the other hand, strong epilimnetic DOC accumulation occurred in Oct 2007 under low light and low PP condition accompanying with high abundance of HNF, implying that HNF grazing may contribute to a certain degree of DOC accumulation. Correlation matrix supported our suggestions. This study testified the DOC dynamics in P-deficient ecosystem are tightly coupled with the source (PP and grazing) and sink (BP). We also suggested that in SRP-limited freshwater systems bacteria are capable of breaking down autochthonous DOC to reduce the chance of DOC

  8. Heavy oil reservoir evaluation : performing an injection test using DST tools in the marine region of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Loaiza, J.; Ruiz, P. [Halliburton, Mexico City (Mexico); Barrera, D.; Gutierrez, F. [Pemex, Mexico City (Mexico)


    This paper described an injection test conducted to evaluate heavy oil reserves in an offshore area of Mexico. The drill-stem testing (DST) evaluation used a fluid injection technique in order to eliminate the need for artificial lift and coiled tubing. A pressure transient analysis method was used to determine the static pressure of the reservoir, effective hydrocarbon permeability, and formation damage. Boundary effects were also characterized. The total volume of the fluid injection was determined by analyzing various reservoir parameters. The timing of the shut-in procedure was determined by characterizing rock characteristics and fluids within the reservoir. The mobility and diffusivity relationships between the zones with the injection fluids and reservoir fluids were used to defined sweep fluids. A productivity analysis was used to predict various production scenarios. DST tools were then used to conduct a pressure-production assessment. Case histories were used to demonstrate the method. The studies showed that the method provides a cost-effective means of providing high quality data for productivity analyses. 4 refs., 2 tabs., 15 figs.

  9. Prediction of limits of lubrication in strip reduction testing

    DEFF Research Database (Denmark)

    Olsson, David Dam; Bay, Niels; Andreasen, Jan Lasson


    Pick-up and galling due to lubricant film breakdown is a severe limitation in cold forming of tribologically difficult metals like stainless steel and aluminium. The present paper describes a method of combined experimental and numerical analysis to quantify the limits of lubrication in a dedicated...... simulative strip reduction test. The limit of lubrication is quantified as the threshold drawing length before galling occurs. A numerical model of the test is established calculating tool/work piece interface temperatures and normal pressures. Identifying a critical maximum value of the interface...

  10. Unconventional geomechanical testing on coal for coalbed reservoir well design: The Alberta foothills and plains

    Energy Technology Data Exchange (ETDEWEB)

    Deisman, Nathan; Chalaturnyk, Richard J. [University of Alberta, Department of Civil and Environmental Engineering, Edmonton, Alberta T6G 2G (Canada); Gentzis, Thomas [Petron Resources LP, 3000 Internet Boulevard, Suite 400, Frisco, Texas 75034 (United States)


    One unconfined compressive strength (UCS) test and four high-pressure triaxial stress tests were conducted on coal cores in order to best emulate the key issues regarding horizontal wellbore stability, coal strength, permeability change, and coal fines generation during the life cycle of a coalbed methane reservoir. The four non-trivial stress paths were: loading compression (LC), where the axial stress is increased while the confining stress is held constant; loading extension (LE), where the axial stress is held constant while the confining stress is increased; unloading compression (ULC), in which the axial stress is held constant while the confining stress is decreased; and unloading extension (ULE), during which the confining stress is held constant while the axial stress is decreased. The UCS test showed the expected fractured response of initial non-linearity due to fracture closure, followed by a linear portion at a certain axial stress, and, finally, by brittle failure of the coal. Along each of the extension stress, and also along the combined compression-extension stress paths, the coal did not show any visual signs of failure. No coal fines were detected in the downstream accumulator subsequent to the permeability tests. Particle size distribution analysis, following loading compression, provided an estimate of the optimum diameter of the liner perforations. Test results showed that, as the mean effective confining stress increased permeability decreased due to closure of cleats. As the coal was loaded, unloaded, and reloaded along the same stress path, a decrease in permeability below the original measured value (permeability hysteresis) was noted. This could be attributed to one or a combination of two mechanisms: deformation due to creep and/or cleat damage from previous loading. Using the best-fit approach, a compressive Hoek-Brown (HB) failure envelope was fit with 'intact' parameters of: geological strength index or GSI=85, D=1.0, {sigma

  11. Testing geopressured geothermal reservoirs in existing wells. Final report: Saldana well No. 2, Zapata County, Texas. Volume II. Well test data

    Energy Technology Data Exchange (ETDEWEB)

    The following are included: field test data, compiled and edited raw data, time/pressure data, tentative method of testing for hydrogen sulfide in natural gas using length of stain tubes, combined sample log, report on reservoir fluids study, well test analysis, smoothing with weighted moving averages, chemical analysis procedures, scale monitoring report, sand detector strip charts, and analyses of water and gas samples. (MHR)

  12. Verification methods for treaties limiting and banning nuclear tests

    International Nuclear Information System (INIS)

    Voloshin, N.P.


    Treaty on limitation of underground nuclear weapon tests and treaty on world banning of nuclear tests contribute to and accompany the process of nuclear disarmament. Test ban in three (Moscow treaty of 1963) as well as the Threshold Test Ban up to 1991 was controlled only with national means. But since 1991 nuclear test threshold of 150 kt has been measured with hydrodynamic and tele seismic methods and checked by the inspection. Distinctive feature of this control is that control is that it is bilateral. This conforms to Treaty on limitation of underground nuclear weapon tests signed by two countries - USA and USSR. The inspection at the place of tests requires monitoring of the test site of the party conducting a test and geological information of rock in the area of explosion. In the treaty of the World Nuclear Test Ban the following ways of international control are provided for: - seismologic measurements; - radionuclide measurements; - hydro-acoustics measurements; - infra-sound measurements; - inspection at the place of the tests conduction

  13. Improvement of productivity for carbonate reservoir. Field test on Khafji oil field in Arabian gulf (field test on Khafji oil field in Arabian gulf); Tansan`enganso seisansei kojo gijutsu. Khafji yuden field test (Khafji yuden field test)

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, F.; Okutsu, H.; Eto, K. [Tech. Research Center, Japan National Oil Corp., Tokyo (Japan)


    Development, demonstration and overall evaluation were given on a productivity improving technology including a well stimulating technology and a horizontal well technology for a carbonate reservoir with low permeability and poor productivity. As an objective test field, the A-limestone reservoir was used in the Khafji oil field in Saudi Arabia, whose rights are possessed by Arabian Oil Company. Furthermore, a fractured reservoir evaluation technology and a well stimulating technology were demonstrated and utilized to enhance the productivity improving technology for carbonate reservoirs. To achieve the objective, it was necessary to evaluate detailed geological features and reservoirs that are worth developing a technology to improve productivity, select an optimal well stimulating technology, and discuss productivity improvement by using horizontal wells. Fiscal 1994 has performed evaluations on geological features and reservoirs, and started drilling the No. 1 experimental well. Activities executed for geological analyses include analyses from fossilization and deposition point of view, analyses of cores taken from newly drilled wells, core fracture analyses, and geological structure analyses using slanted well logging analyses. As a result of drilling the No. 1 experimental well, the vertical well produced oil of about 600 barrels a day, and the horizontal well 2900 barrels a day. 2 figs.

  14. Experimental tests of limiting fragmentation at the ISR

    CERN Document Server

    Bellettini, G; Bradaschia, C; Castaldi, R; Del Prete, T; Finocchiaro, G; Firomini, P; Foà, L; Grannis, P; Green, D; Laurelli, P; Menzione, A; Mustard, R; Thun, R; Valdata, M


    The authors present direct tests of the hypothesis of limiting fragmentation from an experiment at the CERN Intersecting Storage Rings at centre-of-mass energies between 31 and 53 GeV. Single- particle inclusive distributions and partial multiplicity distributions are observed for the case in which the energy of one beam is fixed while varying the energy of the other beam. Within cones around the beam, limiting fragmentation is shown to be valid. (4 refs) .

  15. Investigation of gas hydrate-bearing sandstone reservoirs at the "Mount Elbert" stratigraphic test well, Milne Point, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Boswell, R.M.; Hunter, R. (ASRC Energy Services, Anchorage, AK); Collett, T. (USGS, Denver, CO); Digert, S. (BP Exploration (Alaska) Inc., Anchorage, AK); Hancock, S. (RPS Energy Canada, Calgary, Alberta, Canada); Weeks, M. (BP Exploration (Alaska) Inc., Anchorage, AK); Mt. Elbert Science Team


    In February 2007, the U.S. Department of Energy, BP Exploration (Alaska), Inc., and the U.S. Geological Survey conducted an extensive data collection effort at the "Mount Elbert #1" gas hydrates stratigraphic test well on the Alaska North Slope (ANS). The 22-day field program acquired significant gas hydrate-bearing reservoir data, including a full suite of open-hole well logs, over 500 feet of continuous core, and open-hole formation pressure response tests. Hole conditions, and therefore log data quality, were excellent due largely to the use of chilled oil-based drilling fluids. The logging program confirmed the existence of approximately 30 m of gashydrate saturated, fine-grained sand reservoir. Gas hydrate saturations were observed to range from 60% to 75% largely as a function of reservoir quality. Continuous wire-line coring operations (the first conducted on the ANS) achieved 85% recovery through 153 meters of section, providing more than 250 subsamples for analysis. The "Mount Elbert" data collection program culminated with open-hole tests of reservoir flow and pressure responses, as well as gas and water sample collection, using Schlumberger's Modular Formation Dynamics Tester (MDT) wireline tool. Four such tests, ranging from six to twelve hours duration, were conducted. This field program demonstrated the ability to safely and efficiently conduct a research-level openhole data acquisition program in shallow, sub-permafrost sediments. The program also demonstrated the soundness of the program's pre-drill gas hydrate characterization methods and increased confidence in gas hydrate resource assessment methodologies for the ANS.

  16. Flow characteristic of Hijiori HDR reservoir from circulation test in 1991; Koon tantai Hijiori jikkenjo ni okeru senbu choryuso shiken (1991 nendo) kekka to ryudo kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Shiga, T.; Hyodo, M.; Shinohara, N.; Takasugi, S. [Geothermal Energy Research and Development Co. Ltd., Tokyo (Japan)


    This paper reports one example of flow analyses on a circulation test carried out in fiscal 1991 at the Hijiori hot dry rock experimental field (Yamagata Prefecture). A fluid circulation model was proposed to simulate an HDR circulation system for a shallow reservoir (at a depth of about 1800 m) demonstrated in the circulation test by using an electric circuit network (which expresses continuity impedance in resistance and fluid storage in capacitance). Storage capacity of the reservoir was estimated by deriving time constant of the system from data of time-based change in reservoir pressure associated with transition phenomena during the circulation test. The storage capacity was estimated separately by dividing change of storage in the reservoir by change in the reservoir pressure. To derive the storage in the reservoir, a method to calculate non-recovered flows in the circulation test was utilized. The results of evaluating the reservoir capacity in the shallow reservoir using the above two independent methods were found substantially consistent. 3 refs., 6 figs., 1 tab.

  17. Testing of materials and scale models for impact limiters

    International Nuclear Information System (INIS)

    Maji, A.K.; Satpathi, D.; Schryer, H.L.


    Aluminum Honeycomb and Polyurethane foam specimens were tested to obtain experimental data on the material's behavior under different loading conditions. This paper reports the dynamic tests conducted on the materials and on the design and testing of scale models made out of these open-quotes Impact Limiters,close quotes as they are used in the design of transportation casks. Dynamic tests were conducted on a modified Charpy Impact machine with associated instrumentation, and compared with static test results. A scale model testing setup was designed and used for preliminary tests on models being used by current designers of transportation casks. The paper presents preliminary results of the program. Additional information will be available and reported at the time of presentation of the paper

  18. A test of the Lake Habitat Survey method in Cleveland Reservoir ...

    African Journals Online (AJOL)

    However, there were significant differences in the number of macrophyte species and shoreline/riparian pressures between the two reservoirs. In conclusion, the use of the LHS can better enhance quality and reliability of lake hydromorphological assessments in tropical systems, where such an investigation is required to ...

  19. Limiting the testing of AST: a diagnostically nonspecific enzyme. (United States)

    Xu, Qian; Higgins, Trefor; Cembrowski, George S


    Annually, millions of pairs of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) tests are ordered. These enzymes are highly correlated, and ALT is far more specific diagnostically than AST. To reduce AST testing, we suggest measuring AST only when ALT exceeds a predetermined limit. We derived the proportions of elevated ASTs that would not be measured based on 15 months of paired inpatient and outpatient ALT and AST data. For inpatients, a 35 U/L ALT limit for initiating AST testing would reduce AST testing by 51%, missing only 3% and 7.5% of ASTs exceeding 50 U/L and 35 U/L, respectively. In outpatients, AST testing can be reduced by more than 65%, with fewer missed elevated ASTs (0.5% and 2% of the ASTs exceeding 50 U/L and 35 U/L, respectively). Conservatively, $100 million could be saved annually in the US health care budget by selectively limiting AST testing in just the US outpatient environment. Copyright© by the American Society for Clinical Pathology.

  20. Analysis of pressure falloff tests of non-Newtonian power-law fluids in naturally-fractured bounded reservoirs

    Directory of Open Access Journals (Sweden)

    Omotayo Omosebi


    This article presents an analytic technique for interpreting pressure falloff tests of non-Newtonian Power-law fluids in wells that are located near boundaries in dual-porosity reservoirs. First, dimensionless pressure solutions are obtained and Stehfest inversion algorithm is used to develop new type curves. Subsequently, long-time analytic solutions are presented and interpretation procedure is proposed using direct synthesis. Two examples, including real field data from a heavy oil reservoir in Colombian eastern plains basin, are used to validate and demonstrate application of this technique. Results agree with conventional type-curve matching procedure. The approach proposed in this study avoids the use of type curves, which is prone to human errors. It provides a better alternative for direct estimation of formation and flow properties from falloff data.

  1. Force Limited Random Vibration Test of TESS Camera Mass Model (United States)

    Karlicek, Alexandra; Hwang, James Ho-Jin; Rey, Justin J.


    The Transiting Exoplanet Survey Satellite (TESS) is a spaceborne instrument consisting of four wide field-of-view-CCD cameras dedicated to the discovery of exoplanets around the brightest stars. As part of the environmental testing campaign, force limiting was used to simulate a realistic random vibration launch environment. While the force limit vibration test method is a standard approach used at multiple institutions including Jet Propulsion Laboratory (JPL), NASA Goddard Space Flight Center (GSFC), European Space Research and Technology Center (ESTEC), and Japan Aerospace Exploration Agency (JAXA), it is still difficult to find an actual implementation process in the literature. This paper describes the step-by-step process on how the force limit method was developed and applied on the TESS camera mass model. The process description includes the design of special fixtures to mount the test article for properly installing force transducers, development of the force spectral density using the semi-empirical method, estimation of the fuzzy factor (C2) based on the mass ratio between the supporting structure and the test article, subsequent validating of the C2 factor during the vibration test, and calculation of the C.G. accelerations using the Root Mean Square (RMS) reaction force in the spectral domain and the peak reaction force in the time domain.

  2. Limited streamer chamber testing and quality evaluation in ASTRA

    International Nuclear Information System (INIS)

    Anzivino, G.; Bianco, S.; Casaccia, R.


    Limited streamer chambers are extensively used for high-energy and nuclear physics experiments in accelerator and underground laboratories. The tracking system of LVD, an underground experiment to study muons and nutrino astronomy, will use roughly 15000 limited streamer chambers and 100000 external pickup strips with digital readout electronics. In the article the different aspects of chamber operation that serve to establish a testing procedure and to define acceptance criteria for selecting reliable and long-life devices, are discussed. The procedures and the results obtained from a long-term test to evaluate streamer chamber quality, based upon a sample of 2900 items, are described. The selection tests and the long-term observations have been performed in the ASTRA laboratory, established at the Laboratori Nazionali di Frascati to carry out quality control procedures for streamer chambers on a large scale and in a controlled environment

  3. Characterization and Prediction of the Gas Hydrate Reservoir at the Second Offshore Gas Production Test Site in the Eastern Nankai Trough, Japan

    Directory of Open Access Journals (Sweden)

    Machiko Tamaki


    Full Text Available Following the world’s first offshore production test that was conducted from a gas hydrate reservoir by a depressurization technique in 2013, the second offshore production test has been planned in the eastern Nankai Trough. In 2016, the drilling survey was performed ahead of the production test, and logging data that covers the reservoir interval were newly obtained from three wells around the test site: one well for geological survey, and two wells for monitoring surveys, during the production test. The formation evaluation using the well log data suggested that our target reservoir has a more significant heterogeneity in the gas hydrate saturation distribution than we expected, although lateral continuity of sand layers is relatively good. To evaluate the spatial distribution of gas hydrate, the integration analysis using well and seismic data was performed. The seismic amplitude analysis supports the lateral reservoir heterogeneity that has a significant positive correlation with the resistivity log data at the well locations. The spatial distribution of the apparent low-resistivity interval within the reservoir observed from log data was investigated by the P-velocity volume derived from seismic inversion. The integrated results were utilized for the pre-drill prediction of the reservoir quality at the producing wells. These approaches will reduce the risk of future commercial production from the gas hydrate reservoir.

  4. Limited test data: The choice between confidence limits and inverse probability

    International Nuclear Information System (INIS)

    Nichols, P.


    For a unit which has been successfully designed to a high standard of reliability, any test programme of reasonable size will result in only a small number of failures. In these circumstances the failure rate estimated from the tests will depend on the statistical treatment applied. When a large number of units is to be manufactured, an unexpected high failure rate will certainly result in a large number of failures, so it is necessary to guard against optimistic unrepresentative test results by using a confidence limit approach. If only a small number of production units is involved, failures may not occur even with a higher than expected failure rate, and so one may be able to accept a method which allows for the possibility of either optimistic or pessimistic test results, and in this case an inverse probability approach, based on Bayes' theorem, might be used. The paper first draws attention to an apparently significant difference in the numerical results from the two methods, particularly for the overall probability of several units arranged in redundant logic. It then discusses a possible objection to the inverse method, followed by a demonstration that, for a large population and a very reasonable choice of prior probability, the inverse probability and confidence limit methods give the same numerical result. Finally, it is argued that a confidence limit approach is overpessimistic when a small number of production units is involved, and that both methods give the same answer for a large population. (author)

  5. Testing for Multiple Bubbles: Limit Theory of Real Time Detectors


    Peter C.B. Phillips; Shu-Ping Shi; Jun Yu


    This paper provides the limit theory of real time dating algorithms for bubble detection that were suggested in Phillips, Wu and Yu (2011, PWY) and Phillips, Shi and Yu (2013b, PSY). Bubbles are modeled using mildly explosive bubble episodes that are embedded within longer periods where the data evolves as a stochastic trend, thereby capturing normal market behavior as well as exuberance and collapse. Both the PWY and PSY estimates rely on recursive right tailed unit root tests (each with a d...

  6. Testing geopressured geothermal reservoirs in existing wells. Wells of Opportunity Program final contract report, 1980-1981

    Energy Technology Data Exchange (ETDEWEB)


    The geopressured-geothermal candidates for the Wells of Opportunity program were located by the screening of published information on oil industry activity and through direct contact with the oil and gas operators. This process resulted in the recommendation to the DOE of 33 candidate wells for the program. Seven of the 33 recommended wells were accepted for testing. Of these seven wells, six were actually tested. The first well, the No. 1 Kennedy, was acquired but not tested. The seventh well, the No. 1 Godchaux, was abandoned due to mechanical problems during re-entry. The well search activities, which culminated in the acceptance by the DOE of 7 recommended wells, were substantial. A total of 90,270 well reports were reviewed, leading to 1990 wells selected for thorough geological analysis. All of the reservoirs tested in this program have been restricted by one or more faults or permeability barriers. A comprehensive discussion of test results is presented.

  7. Test of a beryllium limiter in the tokamak UNITOR

    International Nuclear Information System (INIS)

    Hackmann, J.; Uhlenbusch, J.


    Beryllium rail limiters are inserted into the tokamak UNITOR to study the compatibility of this material with the plasma. The power load onto the limiter surface is 1-2 kW/cm 2 during the plasma pulse length of 50 ms duration. The concentration of heavy (Cr) and light (O) impurities is monitored by means of spectroscopy. In comparison with other materials tested likewise (graphite, Ni, Al 2 O 3 , TiC, SiC, SS) the Be-experiments have shown the following improvements: (a) the concentration of heavy impurities is considerably reduced, (b) this reduction is preserved if the poloidal Be-limiters are retracted from the plasma, (c) the plasma resistivity is diminished, (d) the occurrence of disruptions decreases. A total amount of 6 mg beryllium was found distributed on the inner torus wall after 1500 shots. The decontamination of the apparatus was performed without major problems. Only very little volatile Be-dust was detected, and peripheric parts (pumps, mass spectrometer etc.) were not contaminated. The beryllium released from the limiters was found to be entirely deposited on the torus wall mainly in the vicinity of the limiters. (orig.)

  8. Water Saturation Relations and Their Diffusion-Limited Equilibration in Gas Shale: Implications for Gas Flow in Unconventional Reservoirs (United States)

    Tokunaga, Tetsu K.; Shen, Weijun; Wan, Jiamin; Kim, Yongman; Cihan, Abdullah; Zhang, Yingqi; Finsterle, Stefan


    Large volumes of water are used for hydraulic fracturing of low permeability shale reservoirs to stimulate gas production, with most of the water remaining unrecovered and distributed in a poorly understood manner within stimulated regions. Because water partitioning into shale pores controls gas release, we measured the water saturation dependence on relative humidity (rh) and capillary pressure (Pc) for imbibition (adsorption) as well as drainage (desorption) on samples of Woodford Shale. Experiments and modeling of water vapor adsorption into shale laminae at rh = 0.31 demonstrated that long times are needed to characterize equilibrium in larger (5 mm thick) pieces of shales, and yielded effective diffusion coefficients from 9 × 10-9 to 3 × 10-8 m2 s-1, similar in magnitude to the literature values for typical low porosity and low permeability rocks. Most of the experiments, conducted at 50°C on crushed shale grains in order to facilitate rapid equilibration, showed significant saturation hysteresis, and that very large Pc (˜1 MPa) are required to drain the shales. These results quantify the severity of the water blocking problem, and suggest that gas production from unconventional reservoirs is largely associated with stimulated regions that have had little or no exposure to injected water. Gravity drainage of water from fractures residing above horizontal wells reconciles gas production in the presence of largely unrecovered injected water, and is discussed in the broader context of unsaturated flow in fractures.

  9. Candidate reservoirs for enhanced oil recovery, guidelines for their selection and appraisal of significant tests to date. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cronquist, C.; Portugal, D.


    Elements which are keys to the effective management of the ERDA Enhanced Oil Recovery Programs are described. Results of efforts to develop screening criteria to identify reservoir rock-fluid characteristics considered suitable for application of EOR processes which appear to have the best chance for commercial recovery of significant additional volumes of oil are summarized. A review of significant field tests made to develop the management matrices is included. Over a hundred published references describing completed and ongoing tests of EOR processes were reviewed to compile the data reported in the four matrices. The knowledge derived from these and subsequent field tests, plus that derived from laboratory research, serves to continually improve the state-of-the-art, thereby reducing the risk in tests yet to come. As the state-of-the-art improves, and as more data comes into the public domain, the matrices should be updated, and the screening criteria should be revised accordingly. An extensive set of data representing 2,420 reservoirs in the United States which have been identified as potential candidates for enhanced oil recovery is included.

  10. New modelling of transient well test and rate decline analysis for a horizontal well in a multiple-zone reservoir

    International Nuclear Information System (INIS)

    Nie, Ren-Shi; Guo, Jian-Chun; Jia, Yong-Lu; Zhu, Shui-Qiao; Rao, Zheng; Zhang, Chun-Guang


    The no-type curve with negative skin of a horizontal well has been found in the current research. Negative skin is very significant to transient well test and rate decline analysis. This paper first presents the negative skin problem where the type curves with negative skin of a horizontal well are oscillatory. In order to solve the problem, we propose a new model of transient well test and rate decline analysis for a horizontal well in a multiple-zone composite reservoir. A new dimensionless definition of r D is introduced in the dimensionless mathematical modelling under different boundaries. The model is solved using the Laplace transform and separation of variables techniques. In Laplace space, the solutions for both constant rate production and constant wellbore pressure production are expressed in a unified formula. We provide graphs and thorough analysis of the new standard type curves for both well test and rate decline analysis; the characteristics of type curves are the reflections of horizontal well production in a multiple-zone reservoir. An important contribution of our paper is that our model removed the oscillation in type curves and thus solved the negative skin problem. We also show that the characteristics of type curves depend heavily on the properties of different zones, skin factor, well length, formation thickness, etc. Our research can be applied to a real case study

  11. Investigation of gas hydrate-bearing sandstone reservoirs at the Mount Elbert stratigraphic test well, Milne Point, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Boswell, R. [United States Dept. of Energy, Morgantown, WV (United States). National Energy Technology Lab; Hunter, R. [ASRC Energy Services, Anchorage, AK (United States); Collett, T. [United States Geological Survey, Denver, CO (United States); Digert, S.; Weeks, M. [BP Exploration Alaska Inc., Anchorage, AK (United States); Hancock, S. [RPS Energy Canada, Calgary, AB (Canada)


    Gas hydrates occur within the shallow sand reservoirs on the Alaska North Slope (ANS). The mean estimate for gas hydrate in-place resources on the ANS is 16.7 trillion cubic metres. In the past, they were viewed primarily as a drilling hazard to be managed during the development of deeper oil resources. In 2002, a cooperative research program was launched to help determine the potential for environmentally-sound and economically-viable production of methane from gas hydrates. Additional objectives were to refine ANS gas hydrate resource potential, improve the geologic and geophysical methods used to locate and asses gas hydrate resources, and develop numerical modeling capabilities that are essential in both planning and evaluating gas hydrate field programs. This paper reviewed the results of the an extensive data collection effort conducted at the Mount Elbert number 1 gas hydrates stratigraphic test well on the ANS. The 22-day field program acquired significant gas hydrate-bearing reservoir data, including a suite of open-hole well logs, over 500 feet of continuous core, and open-hole formation pressure response tests. The logging program confirmed the existence of approximately 30 m of gas hydrate saturated, fine-grained sand reservoir. Gas hydrate saturations were observed to range from 60 to 75 per cent. Continuous wire-line coring operations achieved 85 per cent recovery. The Mount Elbert field program also involved gas and water sample collection. It demonstrated the ability to safely and efficiently conduct a research-level open-hole data acquisition program in shallow, sub-permafrost sediments and increased confidence in gas hydrate resource assessment methodologies for the ANS. 10 refs., 9 figs.

  12. Testing geopressured geothermal reservoirs in existing wells: Detailed completion prognosis for geopressured-geothermal well of opportunity, prospect #2

    Energy Technology Data Exchange (ETDEWEB)



    A geopressured-geothermal test of Martin Exploration Company's Crown Zellerbach Well No. 2 will be conducted in the Tuscaloosa Trend. The Crown Zellerbach Well No. 1 will be converted to a saltwater disposal well for disposal of produced brine. The well is located in the Satsuma Area, Livingston parish, Louisiana. Eaton proposes to test the Tuscaloosa by perforating the 7 inch casing from 16,718 feet to 16,754 feet. The reservoir pressure at an intermediate formation depth of 16,736 feet is anticipated to be 12,010 psi and the temperature is anticipated to be 297 F. Calculated water salinity is 16,000 ppm. The well is expected to produce a maximum of 16,000 barrels of water a day with a gas content of 51 SCF/bbl. Eaton will re-enter the test well, clean out to 17,000 feet, run production casing and complete the well. The disposal well will be re-entered and completed in the 9-5/8 inch casing for disposal of produced brine. Testing will be conducted similar to previous Eaton annular flow WOO tests. An optional test from 16,462 feet to 16,490 feet may be performed after the original test and will require a workover with a rig on location to perform the plugback. The surface production equipment utilized on previous tests will be utilized on this test. The equipment has worked satisfactorily and all parties involved in the testing are familiar with its operation. Weatherly Engineering will operate the test equipment. The Institute of Gas Technology (IGT) and Mr. Don Clark will handle sampling, testing and reservoir engineering evaluation, respectively. wireline work required will be awarded on basis of bid evaluation. At the conclusion of the test period, the D.O.E. owned test equipment will be removed from the test site, the test and disposal wells plugged and abandoned and the sites restored to the satisfaction of all parties.

  13. Edge profiles and limiter tests in Extrap T2 (United States)

    Bergsåker, H.; Hedin, G.; Ilyinsky, L.; Larsson, D.; Möller, A.

    New edge profile measurements, including calorimetric measurements of the parallel heat flux, were made in Extrap T2. Test limiters of pure molybdenum and the TZM molybdenum alloy have been exposed in the edge plasma. The surface damage was studied, mainly by microscopy. Tungsten coated graphite probes were also exposed, and the surfaces were studied by microscopy, ion beam analysis and XPS. In this case cracking and mixing of carbon and tungsten at the interface was observed in the most heated areas, whereas carbide formation at the surface was seen in less heated areas. In these tests pure Mo generally fared better than TZM, and thin and cleaner coatings fared better than thicker and less clean.

  14. Testing of fractured carbonate oil and gas reservoirs in Western Latvia

    Energy Technology Data Exchange (ETDEWEB)

    Bakhtin, V.V.; Sliznikov, N.I.; Chechetkin, S.I.


    A description is given of fractured carbonate reservoirs in Upper and Middle Ordovician, which have high oil saturation, but do not produce at commercial rates. Low production rates were basically caused by low porosity (4 to 6%) and an integranular permeability of less than 0.1 md. The oil is present in the secondary porosity while oil flow is through a system of microfractures. Low productivity also is caused by use of too dense drilling fuid whose clay reduces formation permeability. A new well completion procedure is suggested, in which the formation is perforated by a sand jet and hydraulically fractured by acid. The acid should be 6% in concentration and should contain 0.1% surfactant DME-15. The cost of fracturing can be reduced by using locally available sand.

  15. Some Limits of Biocompatibility Testing for Lipophilic Leachates

    Directory of Open Access Journals (Sweden)

    Anne D. Lucas


    Full Text Available Medical device standards recommend using both a polar and non-polar solvent to extract materials prior to in vitro testing. Testing lipophilic extract in cell culture systems is limited by the toxicity of the lipophilic solvents used in extraction. Use of agar overlay and direct contact methods do not directly address the problem of testing for highly lipophilic leachates from device or material extracts. This particular problem was approached by 1 use of hydrotropes, and 2 by sealing the suspended cells in dialysis tubing and placing it directly in oil or media. The use of hydrotropes to eliminate micelle formation and increase the solubility of lipophilic compounds was not useful as the hydrotropes themselves were toxic to the cells at concentrations that significantly increased analyte solubility. Diffusion of hydrophobic compounds from either peanut oil or cell culture media into the dialysis tubing where the test cells in media reside was significantly higher for the cell culture media than the peanut oil. There were significant differences in toxicity for cells in dialysis tubing from devices extracted between peanut oil and media. This study illustrates the importance of examining if cell toxicity due to micelle formation versus that of soluble chemicals for lipophilic extracts.

  16. Some Limits of Biocompatibility Testing for Lipophilic Leachates

    Directory of Open Access Journals (Sweden)

    Anne Lucas


    Full Text Available Medical device standards recommend using both a polar and non-polar solvent to extract materials prior to in vitro testingTesting lipophilic extract in cell culture systems is limited by the toxicity of the lipophilic solvents used in extraction. Use of agar overlay and direct contact methods do not directly address the problem of testing for highly lipophilic leachates from device or material extracts. This particular problem was approached by 1 use of hydrotropes, and 2 by sealing the suspended cells in dialysis tubing and placing it directly in oil or media. The use of hydrotropes to eliminate micelle formation and increase the solubility of lipophilic compounds was not useful as the hydrotropes themselves were toxic to the cells at concentrations that significantly increased analyte solubility. Diffusion of hydrophobic compounds from either peanut oil or cell culture media into the dialysis tubing where the test cells in media reside was significantly higher for the cell culture media than the peanut oil. There were significant differences in toxicity for cells in dialysis tubing from devices extracted between peanut oil and media. This study illustrates the importance of examining if cell toxicity due to micelle formation versus that of soluble chemicals for lipophilic extracts.

  17. Damage Detection in Grid Structures Using Limited Modal Test Data

    Directory of Open Access Journals (Sweden)

    Bei-dou Ding


    Full Text Available The detection of potentially damaged elements in grid structures is a challenging topic. By using limited measured test data, damage detection for grid structures is developed by the modal strain energy (MSE method. Two critical problems are considered in this paper in developing the MSE method to detect potential damage to the grid structure by using limited modal test data. First, an updated mode shape expansion method based on the modal assurance criterion is adopted to ensure that the modal shape obtained from the reference baseline model is reliable and has explicit physical meanings. Second, after identifying the location of the element damage by the element MSE method with expanded mode shapes, multivariable parameters denoting element damage severity are simultaneously determined. These parameters are included in the column vector and matched with the corresponding element stiffness matrix while the error tolerance value of the Frobenius norm of the column vector is undercontrolled. Finally, a three-dimension numerical model of the grid structure is used to represent different damage cases and to demonstrate the effectiveness of the present method. The application of the three-dimension physical model to a full-scale grid structure is also verified. Analysis results demonstrate that the presented damage detection method effectively locates and quantifies single- and multimember damage in grid structures and can be applied in engineering practice.

  18. Limit analysis, rammed earth material and Casagrande test (United States)

    El-Nabouch, Ranime; Pastor, Joseph; Bui, Quoc-Bao; Plé, Olivier


    The present paper is concerned with the simulation of the Casagrande test carried out on a rammed earth material for wall-type structures in the framework of Limit Analysis (LA). In a preliminary study, the material is considered as a homogeneous Coulomb material, and existing LA static and kinematic codes are used for the simulation of the test. In each loading case, static and kinematic bounds coincide; the corresponding exact solution is a two-rigid-block mechanism together with a quasi-constant stress vector and a velocity jump also constant along the interface, for the three loading cases. In a second study, to take into account the influence of compressive loadings related to the porosity of the material, an elliptic criterion (denoted Cohesive Cam-Clay, CCC) is defined based on recent homogenization results about the hollow sphere model for porous Coulomb materials. Finally, original finite element formulations of the static and mixed kinematic methods for the CCC material are developed and applied to the Casagrande test. The results are the same than above, except that this time the velocity jump depends on the compressive loading, which is more realistic but not satisfying fully the experimental observations. Therefore, the possible extensions of this work towards non-standard direct methods are analyzed in the conclusion section.

  19. Testing geopressured geothermal reservoirs in existing wells: Detailed completion prognosis for geopressured-geothermal well of opportunity, prospect #7

    Energy Technology Data Exchange (ETDEWEB)

    Godchaux, Frank A.


    This book is a detailed prognosis covering the acquisition, completion, drilling, testing and abandonment of the Frank A. Godchaux, III, Well No. 1 under the Wells of Opportunity Program. The well is located approximately 12 miles southeast of the city of Abbeville, Louisiana. Eaton Operating Company proposes to test a section of the Planulina sand at a depth ranging from 15,584 to 15,692 feet. The reservoir pressure is estimated to be 14,480 psi and the temperature of the formation water is expected to be 298 F. The water salinity is calculated to be 75,000 ppm. The well is expected to produce 20,000 barrels of water per day with a gas content of 44 standard cubic feet pre barrel. The well was acquired from C and K Petroleu, Inc. on March 20, 1981. C and K abandoned the well at a total depth of 16,000 feet. The well has a 7-5/8 inches liner set at 13,387 feet. Eaton proposes to set 5-1/2 inch casing at 16,000 feet and produce the well through the casing using a 2-3/8 inch tubing string for wireline protection and for pressure control. A 4,600 foot saltwater disposal well will be drilled on the site and testing will be conducted similar to previous Eaton tests. The total estimated cost to perform the work is $2,959,000. An optional test from 14,905 to 15,006 feet may be performed after the original test and will require a workover with a rig on location to perform the plugback. The surface production equipment utilized on previous Eaton WOO tests will be utilized on this test. This equipment has worked satisfactorily and all parties involved in the testing are familiar with its operation. The Institute of Gas Technology and Mr. Don Clark will handle the sampling and testing and reservoir evaluation, respectively, as on the previous Eaton tests.

  20. Geological determination of the limits, area and volume of the geothermal reservoir of the Los Humeros geothermal field, Puebla, Mexico; Determinacion geologica de los limites, area y volumen del yacimiento geotermico de Los Humeros, Puebla, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Castillo Hernandez, Daniel [Gerencia de Proyectos Geotermoelectricos, Comision Federal de Electricidad, Morelia, Michoacan (Mexico)


    A geologic analysis to determine the limits, area and volume of the exploitable reservoir of the Los Humeros Geothermal Field, in Puebla, Mexico was carried out. We defined the structural boundaries, both at surface and at deep that seem to control the distribution of the fluids of high enthalpy and favor or limit the production of steam. With 40 wells drilled to date, an average thickness of the lithological producer Unit of 1 163 m has been estimated. A surface of 12.54 km{sup 2} was calculated, that with the estimated thickness, gives a volume of the reservoir of 14.6 km{sup 3}. We consider that there are two main production sectors in the Geothermal Field: The Central Collapse and The Mastaloya Corridor. [Spanish] Se realizo un analisis geologico para determinar los limites, area y volumen del yacimiento explotable del campo geotermico de Los Humeros en Puebla, Mexico. Se definen las barreras estructurales, tanto superficiales como del subsuelo, que controlan la distribucon de los fluidos de alta entalpia que favorecen o limitan la produccion de vapor. Con los 40 pozos perforados hasta la fecha, se estima un espesor promedio de la unidad productora de 1 163 m. Se calculo una superficie de 12.54 km{sup 2}, la que con el espesor mencionado, da un volumen del yacimiento de 14.6 km{sup 3}. Se plantea que dentro del campo existen dos sectores principales de produccion. El Colapso Central y el Corredor de Mastaloya.

  1. Shear-limited test particle diffusion in 2-dimensional plasmas

    International Nuclear Information System (INIS)

    Anderegg, Francois; Driscoll, C. Fred; Dubin, Daniel H.E.


    Measurements of test-particle diffusion in pure ion plasmas show 2D enhancements over the 3D rates, limited by shear in the plasma rotation ω E (r). The diffusion is due to 'long-range' ion-ion collisions in the quiescent, steady-state Mg + plasma. For short plasma length L p and low shear S≡r∂ω E /∂r, thermal ions bounce axially many times before shear separates them in θ, so the ions move in (r,θ) as bounce averaged 'rods' of charge (i.e. 2D point vortices). Experimentally, we vary the number of bounces over the range 0.2≤N b ≤10,000. For long plasmas with N b ≤1, we observe diffusion in quantitative agreement with the 3D theory of long-range ExB drift collisions. For shorter plasmas or lower shear, with N b >1, we measure diffusion rates enhanced by up to 100x. For exceedingly small she0ar, i.e. N b ≥1000, we observe diffusion rates consistent with the Taylor-McNamara estimates for a shear-free thermal plasma. Overall, the data shows fair agreement with Dubin's new theory of 2D diffusion in shear, which predicts an enhancement of D 2D /D 3D ≅N b up to the Taylor-McNamara limit


    Energy Technology Data Exchange (ETDEWEB)

    Matthias G. Imhof; James W. Castle


    The objective of the project is to examine how seismic and geologic data can be used to improve characterization of small-scale heterogeneity and their parameterization in reservoir models. The study is performed at West Coalinga Field in California. We continued our investigation on the nature of seismic reactions from heterogeneous reservoirs. We began testing our algorithm to infer parameters of object-based reservoir models from seismic data. We began integration of seismic and geologic data to determine the deterministic limits of conventional seismic data interpretation. Lastly, we began integration of seismic and geologic heterogeneity using stochastic models conditioned both on wireline and seismic data.

  3. Synthetic well test modelling in a high net-to-gross outcrop system for turbidite reservoir description

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, E.; Corbett, P.W.M. [Heriot-Watt Univ., Dept. of Petroleum Engineering, Edinburgh (United Kingdom); Hurst, A.; Satur, N.; Cronin, B.T. [Aberdeen Univ., Dept. of Petroleum Geology, Aberdeen (United Kingdom)


    Synthetic well tests have been produced using a 3D model of an outcropping turbidite sandstone unit from the Cingoz region in southern Turkey. The model contains realistic sand sheet, tongue, lobe and background sand facies architecture (i.e. geometry and stacking) mapped from an outcrop study. The geometric information is useful as an analogue for high net-to-gross turbidite oil fields. The facies have been assigned petrophysical properties from a subsurface analogue. There is little shale in this system. Well test responses were then derived from the high net-to-gross tubidite model using various architectural, porosity-permeability scenarios and completion strategies. The impact on well test derivatives of various sand body geometries and permeability contrasts could then be determined. Two completion strategies - partial penetration and fully perforated intervals - were assessed for the applicability in the high net-to-gross system. The geological model is effectively a sandbox, and shows a very uniform testing response from the rather uniform property distributions. However, when the level of permeability heterogeneity is increased by populating the model with varying contrasts of permeability and porosity, the sand body geometry can be seen to influence the well tests. Partial completions in sand bodies are particularly effective in detecting sand body geometry. The geometry controls the flow regimes in a well test response despite variations in the permeability contrasts. The effect of varying geometry is illustrated and an external linear flow regime is identified. Where there is sufficient sand body thickness, partial perforation results in spherical flow, from which a vertical permeability can be obtained. In the model, the vertical permeability thus obtained is a local (to the volume investigated) effective permeability of stacked isotropic facies. This work was undertaken to give guidance on the description of hydrocarbon reservoirs by well testing. If

  4. Testing geopressured geothermal reservoirs in existing wells: Pauline Kraft Well No. 1, Nueces County, Texas. Final report

    Energy Technology Data Exchange (ETDEWEB)


    The Pauline Kraft Well No. 1 was originally drilled to a depth of 13,001 feet and abandoned as a dry hole. The well was re-entered in an effort to obtain a source of GEO/sup 2/ energy for a proposed gasohol manufacturing plant. The well was tested through a 5-inch by 2-3/8 inch annulus. The geological section tested was the Frio-Anderson sand of Mid-Oligocene age. The interval tested was from 12,750 to 12,860 feet. A saltwater disposal well was drilled on the site and completed in a Micocene sand section. The disposal interval was perforated from 4710 to 4770 feet and from 4500 to 4542 feet. The test well failed to produce water at substantial rates. Initial production was 34 BWPD. A large acid stimulation treatment increased productivity to 132 BWPD, which was still far from an acceptable rate. During the acid treatment, a failure of the 5-inch production casing occurred. The poor production rates are attributed to a reservoir with very low permeability and possible formation damage. The casing failure is related to increased tensile strain resulting from cooling of the casing by acid and from the high surface injection pressure. The location of the casing failure is now known at this time, but it is not at the surface. Failure as a result of a defect in a crossover joint at 723 feet is suspected.

  5. Testing limits to airflow perturbation device (APD measurements

    Directory of Open Access Journals (Sweden)

    Jamshidi Shaya


    Full Text Available Abstract Background The Airflow Perturbation Device (APD is a lightweight, portable device that can be used to measure total respiratory resistance as well as inhalation and exhalation resistances. There is a need to determine limits to the accuracy of APD measurements for different conditions likely to occur: leaks around the mouthpiece, use of an oronasal mask, and the addition of resistance in the respiratory system. Also, there is a need for resistance measurements in patients who are ventilated. Method Ten subjects between the ages of 18 and 35 were tested for each station in the experiment. The first station involved testing the effects of leaks of known sizes on APD measurements. The second station tested the use of an oronasal mask used in conjunction with the APD during nose and mouth breathing. The third station tested the effects of two different resistances added in series with the APD mouthpiece. The fourth station tested the usage of a flexible ventilator tube in conjunction with the APD. Results All leaks reduced APD resistance measurement values. Leaks represented by two 3.2 mm diameter tubes reduced measured resistance by about 10% (4.2 cmH2O·sec/L for control and 3.9 cm H2O·sec/L for the leak. This was not statistically significant. Larger leaks given by 4.8 and 6.4 mm tubes reduced measurements significantly (3.4 and 3.0 cm cmH2O·sec/L, respectively. Mouth resistance measured with a cardboard mouthpiece gave an APD measurement of 4.2 cm H2O·sec/L and mouth resistance measured with an oronasal mask was 4.5 cm H2O·sec/L; the two were not significantly different. Nose resistance measured with the oronasal mask was 7.6 cm H2O·sec/L. Adding airflow resistances of 1.12 and 2.10 cm H2O·sec/L to the breathing circuit between the mouth and APD yielded respiratory resistance values higher than the control by 0.7 and 2.0 cm H2O·sec/L. Although breathing through a 52 cm length of flexible ventilator tubing reduced the APD

  6. Reservoir management

    International Nuclear Information System (INIS)

    Satter, A.; Varnon, J.E.; Hoang, M.T.


    A reservoir's life begins with exploration leading to discovery followed by delineation of the reservoir, development of the field, production by primary, secondary and tertiary means, and finally to abandonment. Sound reservoir management is the key to maximizing economic operation of the reservoir throughout its entire life. Technological advances and rapidly increasing computer power are providing tools to better manage reservoirs and are increasing the gap between good and neutral reservoir management. The modern reservoir management process involves goal setting, planning, implementing, monitoring, evaluating, and revising plans. Setting a reservoir management strategy requires knowledge of the reservoir, availability of technology, and knowledge of the business, political, and environmental climate. Formulating a comprehensive management plan involves depletion and development strategies, data acquisition and analyses, geological and numerical model studies, production and reserves forecasts, facilities requirements, economic optimization, and management approval. This paper provides management, engineers geologists, geophysicists, and field operations staff with a better understanding of the practical approach to reservoir management using a multidisciplinary, integrated team approach

  7. [Vision test device: possibilities and limits of LCD technique]. (United States)

    Ettelt; Brandl, H; Zrenner, E; Lund, O E


    An automatic visual acuity test examining visual acuity at 5 m distance is presented. An LCD screen with 400 x 640 pixel is used for graphic display. The Landolt rings are selected randomly. The test presented here complies well with the criteria of DIN 58220. Accuracy estimates for representation of the Landolt rings in raster graphics are discussed. With the method suggested, the testing of visual acuity, one of the most important tests in ophthalmological practice, is simplified and its reliability and results are improved. The method allows tests at short time intervals to trace the time dependency of visual acuity. Furthermore, the test may be delegated to support personnel.

  8. The limits of genome-wide methods for pharmacogenomic testing. (United States)

    Gamazon, Eric R; Skol, Andrew D; Perera, Minoli A


    technologies' ability to survey fully the variation in genes of particular interest to the pharmacogenetics community. Our findings demonstrate the limitations of genome-wide methods and the challenges of implementing pharmacogenomic tests into the clinical context.

  9. Validating safeguards effectiveness given inherently limited test data

    International Nuclear Information System (INIS)

    Sicherman, A.


    A key issue in designing and evaluating nuclear safeguards systems is how to validate safeguards effectiveness against a spectrum of potential threats. Safeguards effectiveness is measured by a performance indicator such as the probability of defeating an adversary attempting a malevolent act. Effectiveness validation means a testing program that provides sufficient evidence that the performance indicator is at an acceptable level. Traditional statistical program when numerous independent system trials are possible. However, within the safeguards environment, many situations arise for which traditional statistical approaches may be neither feasible nor appropriate. Such situations can occur, for example, when there are obvious constraints on the number of possible tests due to operational impacts and testing costs. Furthermore, these tests are usually simulations (e.g., staged force-on-force exercises) rather than actual tests, and the system is often modified after each test. Under such circumstances, it is difficult to make and justify inferences about system performance by using traditional statistical techniques. In this paper, the authors discuss several alternative quantitative techniques for validating system effectiveness. The techniques include: (1) minimizing the number of required tests using sequential testing; (2) combining data from models inspections and exercises using Bayesian statistics to improve inferences about system performance; and (3) using reliability growth and scenario modeling to help specify which safeguards elements and scenarios to test

  10. Applying Flammability Limit Probabilities and the Normoxic Upward Limiting Pressure Concept to NASA STD-6001 Test 1 (United States)

    Olson, Sandra L.; Beeson, Harold; Fernandez-Pello, A. Carlos


    Repeated Test 1 extinction tests near the upward flammability limit are expected to follow a Poisson process trend. This Poisson process trend suggests that rather than define a ULOI and MOC (which requires two limits to be determined), it might be better to define a single upward limit as being where 1/e (where e (approx. equal to 2.7183) is the characteristic time of the normalized Poisson process) of the materials burn, or, rounding, where approximately 1/3 of the samples fail the test (and burn). Recognizing that spacecraft atmospheres will not bound the entire oxygen-pressure parameter space, but actually lie along the normoxic atmosphere control band, we can focus the materials flammability testing along this normoxic band. A Normoxic Upward Limiting Pressure (NULP) is defined that determines the minimum safe total pressure for a material within the constant partial pressure control band. Then, increasing this pressure limit by a factor of safety, we can define the material as being safe to use at the NULP + SF (where SF is on the order of 10 kilopascal, based on existing flammability data). It is recommended that the thickest material to be tested with the current Test 1 igniter should be 3 mm thick (1/8 inches) to avoid the problem of differentiating between an ignition limit and a true flammability limit.

  11. Testing of Liquid Lithium Limiters in CDX-U

    Energy Technology Data Exchange (ETDEWEB)

    R. Majeski; R. Kaita; M. Boaz; P. Efthimion; T. Gray; B. Jones; D. Hoffman; H. Kugel; J. Menard; T. Munsat; A. Post-Zwicker; V. Soukhanovskii; J. Spaleta; G. Taylor; J. Timberlake; R. Woolley; L. Zakharov; M. Finkenthal; D. Stutman; G. Antar; R. Doerner; S. Luckhardt; R. Seraydarian; R. Maingi; M. Maiorano; S. Smith; D. Rodgers


    Part of the development of liquid metals as a first wall or divertor for reactor applications must involve the investigation of plasma-liquid metal interactions in a functioning tokamak. Most of the interest in liquid-metal walls has focused on lithium. Experiments with lithium limiters have now been conducted in the Current Drive Experiment-Upgrade (CDX-U) device at the Princeton Plasma Physics Laboratory. Initial experiments used a liquid-lithium rail limiter (L3) built by the University of California at San Diego. Spectroscopic measurements showed some reduction of impurities in CDX-U plasmas with the L3, compared to discharges with a boron carbide limiter. While no reduction in recycling was observed with the L3, which had a plasma-wet area of approximately 40 cm2, subsequent experiments with a larger area fully toroidal lithium limiter demonstrated significant reductions in both recycling and in impurity levels. Two series of experiments with the toroidal limiter have now be en performed. In each series, the area of exposed, clean lithium was increased, until in the latest experiments the liquid-lithium plasma-facing area was increased to 2000 cm2. Under these conditions, the reduction in recycling required a factor of eight increase in gas fueling in order to maintain the plasma density. The loop voltage required to sustain the plasma current was reduced from 2 V to 0.5 V. This paper summarizes the technical preparations for lithium experiments and the conditioning required to prepare the lithium surface for plasma operations. The mechanical response of the liquid metal to induced currents, especially through contact with the plasma, is discussed. The effect of the lithium-filled toroidal limiter on plasma performance is also briefly described.

  12. Testing of Liquid Lithium Limiters in CDX-U

    International Nuclear Information System (INIS)

    Majeski, R.; Kaita, R.; Boaz, M.; Efthimion, P.; Gray, T.; Jones, B.; Hoffman, D.; Kugel, H.; Menard, J.; Munsat, T.; Post-Zwicker, A.; Soukhanovskii, V.; Spaleta, J.; Taylor, G.; Timberlake, J.; Woolley, R.; Zakharov, L.; Finkenthal, M.; Stutman, D.; Antar, G.; Doerner, R.; Luckhardt, S.; Seraydarian, R.; Maingi, R.; Maiorano, M.; Smith, S.; Rodgers, D.


    Part of the development of liquid metals as a first wall or divertor for reactor applications must involve the investigation of plasma-liquid metal interactions in a functioning tokamak. Most of the interest in liquid-metal walls has focused on lithium. Experiments with lithium limiters have now been conducted in the Current Drive Experiment-Upgrade (CDX-U) device at the Princeton Plasma Physics Laboratory. Initial experiments used a liquid-lithium rail limiter (L3) built by the University of California at San Diego. Spectroscopic measurements showed some reduction of impurities in CDX-U plasmas with the L3, compared to discharges with a boron carbide limiter. While no reduction in recycling was observed with the L3, which had a plasma-wet area of approximately 40 cm2, subsequent experiments with a larger area fully toroidal lithium limiter demonstrated significant reductions in both recycling and in impurity levels. Two series of experiments with the toroidal limiter have now be en performed. In each series, the area of exposed, clean lithium was increased, until in the latest experiments the liquid-lithium plasma-facing area was increased to 2000 cm2. Under these conditions, the reduction in recycling required a factor of eight increase in gas fueling in order to maintain the plasma density. The loop voltage required to sustain the plasma current was reduced from 2 V to 0.5 V. This paper summarizes the technical preparations for lithium experiments and the conditioning required to prepare the lithium surface for plasma operations. The mechanical response of the liquid metal to induced currents, especially through contact with the plasma, is discussed. The effect of the lithium-filled toroidal limiter on plasma performance is also briefly described

  13. Simulation of Reservoir Sediment Flushing of the Three Gorges Reservoir Using an Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Xueying Li


    Full Text Available Reservoir sedimentation and its effect on the environment are the most serious world-wide problems in water resources development and utilization today. As one of the largest water conservancy projects, the Three Gorges Reservoir (TGR has been controversial since its demonstration period, and sedimentation is the major concern. Due to the complex physical mechanisms of water and sediment transport, this study adopts the Error Back Propagation Training Artificial Neural Network (BP-ANN to analyze the relationship between the sediment flushing efficiency of the TGR and its influencing factors. The factors are determined by the analysis on 1D unsteady flow and sediment mathematical model, mainly including reservoir inflow, incoming sediment concentration, reservoir water level, and reservoir release. Considering the distinguishing features of reservoir sediment delivery in different seasons, the monthly average data from 2003, when the TGR was put into operation, to 2011 are used to train, validate, and test the BP-ANN model. The results indicate that, although the sample space is quite limited, the whole sediment delivery process can be schematized by the established BP-ANN model, which can be used to help sediment flushing and thus decrease the reservoir sedimentation.

  14. 14 CFR 29.725 - Limit drop test. (United States)


    ...=ratio of assumed rotor lift to the rotorcraft weight. d=deflection under impact of the tire (at the proper inflation pressure) plus the vertical component of the axle travel (inches) relative to the drop mass. n=limit inertia load factor. n j=the load factor developed, during impact, on the mass used in...

  15. Evaluation of gas condensate reservoir behavior using velocity dependent relative permeability during the numerical well test analysis

    Directory of Open Access Journals (Sweden)

    Arash Azamifard


    Full Text Available Gas condensate is one of the most different fluids in reservoir simulation due to retrograde condensation in case of pressure reduction. In this kind of fluids, two phenomena named negative inertia and positive coupling, become significant in the high velocity zone around the wellbore. In this study, a modified black oil simulator is developed that take into account the velocity dependent relative permeability. Against the industrial simulator that assumes linear variation of transmissibilities by pressure, modified black oil nonlinear equations are solved directly without linearization. The developed code is validated by ECLIPSE simulator. The behavior of two real gas condensate fluids, a lean and a rich one, are compared with each other. For each fluid, simulations of PVT experiments are carried out to calculate black oil property applying Coats approach for gas condensate fluids. For both fluids, the proposed models for gas condensate velocity dependent relative permeability show different influence of velocity on relative permeability in the same conditions. Moreover, it is observed that higher flow rate of gas production leads to more condensate production during constant rate well testing.

  16. 14 CFR 27.725 - Limit drop test. (United States)


    ... under impact of the tire (at the proper inflation pressure) plus the vertical component of the axle..., during impact, on the mass used in the drop test (i.e., the acceleration dv/dt in g's recorded in the...

  17. Limitation of using synthetic human odours to test mosquito repellents

    Directory of Open Access Journals (Sweden)

    Mbeyela Edgar


    Full Text Available Abstract Background Gold-standard tests of mosquito repellents involve exposing human volunteers to host-seeking mosquitoes, to assess the protective efficacy of the repellents. These techniques are not exposure-free and cannot be performed prior to toxicological evaluation. It is postulated that synthetic lures could provide a useful assay that mimics in-vivo conditions for use in high-throughput screening for mosquito repellents. Methods This paper reports on a semi-field evaluation of repellents using a synthetic blend of human derived attractants for the malaria vector, Anopheles gambiae sensu stricto Different concentrations of known repellents, N, N diethyl-3-methylbenzamide (deet and Para-methane-3, 8, diol (PMD were added into traps baited with the synthetic blend, and resulting changes in mosquito catches were measured. Results All test concentrations of deet (0.001% to 100% reduced the attractiveness of the synthetic blend. However, PMD was repellent only at 0.25%. Above this concentration, it significantly increased the attractiveness of the blend. There was no relationship between the repellent concentrations and the change in mosquito catches when either deet (r2 = 0.033, P = 0.302 or PMD (r2 = 0.020, P = 0.578 was used. Conclusion It is concluded that while some repellents may reduce the attractiveness of synthetic human odours, others may instead increase their attractiveness. Such inconsistencies indicate that even though the synthetic attractants may provide exposure-free and consistent test media for repellents, careful selection and multiple-repellent tests are necessary to ascertain their suitability for use in repellent screening. The synthetic odour blend tested here is not yet sufficiently refined to serve as replacement for humans in repellent testing, but may be developed further and evaluated in different formats for exposure free repellent testing purposes.

  18. Limiter (United States)

    Cohen, S.A.; Hosea, J.C.; Timberlake, J.R.


    A limiter with a specially contoured front face is provided. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution. This limiter shape accommodates the various power scrape-off distances lambda p, which depend on the parallel velocity, V/sub parallel/, of the impacting particles.

  19. 14 CFR 23.725 - Limit drop tests. (United States)


    ... used in the drop test (lbs.); h=specified free drop height (inches); d=deflection under impact of the tire (at the approved inflation pressure) plus the vertical component of the axle travel relative to... must be made on the complete airplane, or on units consisting of wheel, tire, and shock absorber, in...

  20. Laboratory evaluation of the improved tube test detection limits for ...

    African Journals Online (AJOL)

    In Kenya there is currently no screening of antimicrobial drug residues in milk. This study evaluated the improved tube test as a possible screening method using seven representatives of the β-lactam antibiotics. The group comprises antimicrobials most frequently used to treat bacterial infections in dairy cows.


    Energy Technology Data Exchange (ETDEWEB)

    Jack Bergeron; Tom Blasingame; Louis Doublet; Mohan Kelkar; George Freeman; Jeff Callard; David Moore; David Davies; Richard Vessell; Brian Pregger; Bill Dixon; Bryce Bezant


    Reservoir performance and characterization are vital parameters during the development phase of a project. Infill drilling of wells on a uniform spacing, without regard to characterization does not optimize development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, especially carbonate reservoirs. These reservoirs are typically characterized by: (1) large, discontinuous pay intervals; (2) vertical and lateral changes in reservoir properties; (3) low reservoir energy; (4) high residual oil saturation; and (5) low recovery efficiency. The operational problems they encounter in these types of reservoirs include: (1) poor or inadequate completions and stimulations; (2) early water breakthrough; (3) poor reservoir sweep efficiency in contacting oil throughout the reservoir as well as in the nearby well regions; (4) channeling of injected fluids due to preferential fracturing caused by excessive injection rates; and (5) limited data availability and poor data quality. Infill drilling operations only need target areas of the reservoir which will be economically successful. If the most productive areas of a reservoir can be accurately identified by combining the results of geological, petrophysical, reservoir performance, and pressure transient analyses, then this ''integrated'' approach can be used to optimize reservoir performance during secondary and tertiary recovery operations without resorting to ''blanket'' infill drilling methods. New and emerging technologies such as geostatistical modeling, rock typing, and rigorous decline type curve analysis can be used to quantify reservoir quality and the degree of interwell communication. These results can then be used to develop a 3-D simulation model for prediction of infill locations. The application of reservoir surveillance techniques to identify additional reservoir ''pay'' zones

  2. A limitation of the Cognitive Reflection Test: familiarity

    Directory of Open Access Journals (Sweden)

    Stefan Stieger


    Full Text Available The Cognitive Reflection Test (CRT; Frederick, 2005 is a frequently used measure of cognitive vs. intuitive reflection. It is also a frequently found entertaining ‘test’ on the Internet. In a large age-stratified community-based sample (N = 2,272, we analyzed the impact of having already performed the CRT or any similar task in the past. Indeed, we found that 44% of participants had experiences with these tasks, which was reflected in higher CRT scores (Cohen’s d = 0.41. Furthermore, experienced participants were different from naïve participants in regard to their socio-demographics (younger, higher educated, fewer siblings, more likely single or in a relationship than married, having no children. The best predictors of a high CRT score were the highest educational qualification (4.62% explained variance followed by the experience with the task (3.06%. Therefore, we suggest using more recent multi-item CRTs with newer items and a more elaborated test construction.

  3. Education in Japan: testing the limits of asian education

    Directory of Open Access Journals (Sweden)

    David Blake Willis


    Full Text Available A re-imagining of education is taking place throughout the world with the 21st century in mind and nowhere is this being tested, probed, and critiqued more than in Asia. This new era sees social phenomena as polycentric and polycontextual rather than bilateral or unidirectional. Asia is first and foremost where education in the 21st century is seeing its most spectacular engagement and growth. We view the Japa- nese example with its multiple, textured approaches as one of the heralds of this new global conversation for an education that responds to the transnational, transcultural characteristics of the new age that has daw- ned upon us. Combining Confucian, North American, European, and global approaches – all of which are having an impact on other nations of Asia – Japan represents the cutting edge of a new wave for understan- ding education that has movement as a central motif and strategy.

  4. Nuclear register applications and pressure tests to foresee reservoirs exploitation with water drive; Aplicaciones de registros nucleares y pruebas de presion para predecir el grado de explotacion de reservorios con impulsion de agua

    Energy Technology Data Exchange (ETDEWEB)

    Osorio F, X.; Redosado G, V. [PETROPERU S.A., Lima (Peru)


    This paper illustrates how the pulsed neutron log and well test analysis aid proper reservoir management in strong water reservoirs. These techniques have been applied to Cetico reservoir which belongs to Corrientes Field which is located in the Peruvian Jungle. Corrientes is the most important field operated by PETROPERU S.A. As a result of the analysis we current know the present areal water saturation distribution and also have improve the reservoir characterization al of which is being used for increasing the oil production and reserves. (author). 4 refs, 7 figs, 3 tabs.

  5. Testing the Limits to Accurate Comminution Dates: A Progress Report (United States)

    Piccione, G.; Blackburn, T.; Edwards, G. H.


    The ability to resolve the timing of fine particle production holds potential for contributing to several Earth Science sub-disciplines including glaciology, eolian and fluvial geomorphology, soil production, and fault dynamics. A relatively new geochronologic tool, U-series comminution dating, has shown potential to directly date the timing of particle comminution. This system's sensitivity to particle size arises from a physical disequilibrium in the 238U decay chain generated by the ejected loss of intermediate daughter products (e.g. 234U). It is the goal of this ongoing study to develop and test analytical procedures to improve the accuracy of comminution dating. In the geologic settings explored by previous studies, comminution dates integrate both the time of particle transport and time since deposition. To better test the accuracy of comminution dates, our study focuses on settings where silt has experienced little to no transport time, specifically, glacial moraines in the Eastern Sierras and Rock Avalanches in the San Gabriel Mountains, both locations with existing independent geochronologic constraints. Previous studies demonstrate the dependency of U-series comminution date on grain size and shape. Here we show that mineralogy of samples also plays a role, possibly controlled by the uranium content and crystal bond strength. To separate samples by size and mineralogy, we use dry sonic-sieving, density and magnetic separation. Non-detrital materials deposited on the rim of comminuted grains have an isotopic composition that is unrelated to the isotopic evolution since comminution and therefore must be removed through a multi-step leaching procedure. Leaching is complicated by the fact that areas within the comminuted crystal that have experienced physical fractionation are contained within damaged zones and are prone to being leached themselves, which removes areas of interest from the crystal. We present progress made on a sample processing method

  6. The role of reservoir characterization in the reservoir management process (as reflected in the Department of Energy`s reservoir management demonstration program)

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, M.L. [BDM-Petroleum Technologies, Bartlesville, OK (United States); Young, M.A.; Madden, M.P. [BDM-Oklahoma, Bartlesville, OK (United States)] [and others


    Optimum reservoir recovery and profitability result from guidance of reservoir practices provided by an effective reservoir management plan. Success in developing the best, most appropriate reservoir management plan requires knowledge and consideration of (1) the reservoir system including rocks, and rock-fluid interactions (i.e., a characterization of the reservoir) as well as wellbores and associated equipment and surface facilities; (2) the technologies available to describe, analyze, and exploit the reservoir; and (3) the business environment under which the plan will be developed and implemented. Reservoir characterization is the essential to gain needed knowledge of the reservoir for reservoir management plan building. Reservoir characterization efforts can be appropriately scaled by considering the reservoir management context under which the plan is being built. Reservoir management plans de-optimize with time as technology and the business environment change or as new reservoir information indicates the reservoir characterization models on which the current plan is based are inadequate. BDM-Oklahoma and the Department of Energy have implemented a program of reservoir management demonstrations to encourage operators with limited resources and experience to learn, implement, and disperse sound reservoir management techniques through cooperative research and development projects whose objectives are to develop reservoir management plans. In each of the three projects currently underway, careful attention to reservoir management context assures a reservoir characterization approach that is sufficient, but not in excess of what is necessary, to devise and implement an effective reservoir management plan.

  7. Mobility limitation in self-described well-functioning older adults : importance of endurance walk testing

    NARCIS (Netherlands)

    Simonsick, Eleanor M; Newman, Anne B; Visser, Marjolein; Goodpaster, Bret; Kritchevsky, Stephen B; Rubin, Susan; Nevitt, Michael C; Harris, Tamara B

    BACKGROUND: Mobility limitations are prevalent, potentially reversible precursors to mobility loss that may go undetected in older adults. This study evaluates standardized administration of an endurance walk test for identifying unrecognized and impending mobility limitation in community elders.

  8. Testing the 87Sr/86Sr isotopic ratio measured by ICP-MS as a tracer for inter-well investigation in oil reservoirs

    Directory of Open Access Journals (Sweden)

    Palmieri H.E.L.


    Full Text Available The use of the 87Sr/86Sr isotope ratio has been tested as a natural tracer for inter-well tests in oil reservoirs using standard mass-spectrometry equipment. Such an application can have a special interest to offshore oil fields. Strontium is a relatively abundant component of the dissolved solids in seawater and exhibits a rather constant concentration worldwide. It is also present in the formation water in oil reservoirs in a different concentration and with different isotopic signatures. Hence seawater injection procedures in secondary recovery of the oil can disturb the original isotope ratio in a way that may reflect what is happening inside the reservoir. This study is concerned with the breakthrough of the injected water in production wells. The capability of a single collector quadrupole internal coupled plasma mass spectrometer for detecting the small variations in the 87Sr/86Sr ratio is evaluated. The strategy for dealing with isobaric interference is addressed. The isotope ratio approach is compared with the straightforward use of strontium concentration as the tracer.

  9. Testing the 87Sr/86Sr isotopic ratio measured by ICP-MS as a tracer for inter-well investigation in oil reservoirs (United States)

    dos Santos, M. E.; Palmieri, H. E. L.; Moreira, R. M.


    The use of the 87Sr/86Sr isotope ratio has been tested as a natural tracer for inter-well tests in oil reservoirs using standard mass-spectrometry equipment. Such an application can have a special interest to offshore oil fields. Strontium is a relatively abundant component of the dissolved solids in seawater and exhibits a rather constant concentration worldwide. It is also present in the formation water in oil reservoirs in a different concentration and with different isotopic signatures. Hence seawater injection procedures in secondary recovery of the oil can disturb the original isotope ratio in a way that may reflect what is happening inside the reservoir. This study is concerned with the breakthrough of the injected water in production wells. The capability of a single collector quadrupole internal coupled plasma mass spectrometer for detecting the small variations in the 87Sr/86Sr ratio is evaluated. The strategy for dealing with isobaric interference is addressed. The isotope ratio approach is compared with the straightforward use of strontium concentration as the tracer.

  10. Parcperdue geopressure-geothermal project. Study a geopressured reservoir by drilling and producing a well in a limited geopressured water sand. Final technical report, September 28, 1979-December 31, 1983

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, J.R.; Stanley, J.G. (eds.)


    The behavior of geopressured reservoirs was investigated by drilling and producing a well in small, well defined, geopressured reservoir; and performing detailed pressure transient analysis together with geological, geophysical, chemical, and physical studies. The Dow-DOE L. R. Sweezy No. 1 well was drilled to a depth of 13,600 feet in Parcperdue field, just south of Lafayette, Louisiana, and began production in April, 1982. The production zone was a poorly consolidated sandstone which constantly produced sand into the well stream, causing damage to equipment and causing other problems. The amount of sand production was kept manageable by limiting the flow rate to below 10,000 barrels per day. Reservoir properties of size, thickness, depth, temperature, pressure, salinity, porosity, and permeability were close to predicted values. The reservoir brine was undersaturated with respect to gas, containing approximately 20 standard cubic feet of gas per barrel of brine. Shale dewatering either did not occur or was insignificant as a drive mechanism. Production terminated when the gravel-pack completion failed and the production well totally sanded in, February, 1983. Total production up to the sanding incident was 1.94 million barrels brine and 31.5 million standard cubic feet gas.

  11. GA-4/GA-9 honeycomb impact limiter tests and analytical model

    International Nuclear Information System (INIS)

    Koploy, M.A.; Taylor, C.S.


    General Atomics (GA) has a test program underway to obtain data on the behavior of a honeycomb impact limiter. The program includes testing of small samples to obtain basic information, as well as testing of complete 1/4-scale impact limiters to obtain load-versus-deflection curves for different crush orientations. GA has used the test results to aid in the development of an analytical model to predict the impact limiter loads. The results also helped optimize the design of the impact limiters for the GA-4 and GA-9 Casks

  12. Price limits and stock market efficiency: Evidence from rolling bicorrelation test statistic

    International Nuclear Information System (INIS)

    Lim, Kian-Ping; Brooks, Robert D.


    Using the rolling bicorrelation test statistic, the present paper compares the efficiency of stock markets from China, Korea and Taiwan in selected sub-periods with different price limits regimes. The statistical results do not support the claims that restrictive price limits and price limits per se are jeopardizing market efficiency. However, the evidence does not imply that price limits have no effect on the price discovery process but rather suggesting that market efficiency is not merely determined by price limits.

  13. Modeling reservoir geomechanics using discrete element method : Application to reservoir monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Alassi, Haitham Tayseer


    Understanding reservoir geomechanical behavior is becoming more and more important for the petroleum industry. Reservoir compaction, which may result in surface subsidence and fault reactivation, occurs during reservoir depletion. Stress changes and possible fracture development inside and outside a depleting reservoir can be monitored using time-lapse (so-called '4D') seismic and/or passive seismic, and this can give valuable information about the conditions of a given reservoir during production. In this study we will focus on using the (particle-based) Discrete Element Method (DEM) to model reservoir geomechanical behavior during depletion and fluid injection. We show in this study that DEM can be used in modeling reservoir geomechanical behavior by comparing results obtained from DEM to those obtained from analytical solutions. The match of the displacement field between DEM and the analytical solution is good, however there is mismatch of the stress field which is related to the way stress is measured in DEM. A good match is however obtained by measuring the stress field carefully. We also use DEM to model reservoir geomechanical behavior beyond the elasticity limit where fractures can develop and faults can reactivate. A general technique has been developed to relate DEM parameters to rock properties. This is necessary in order to use correct reservoir geomechanical properties during modeling. For any type of particle packing there is a limitation that the maximum ratio between P- and S-wave velocity Vp/Vs that can be modeled is 3 . The static behavior for a loose packing is different from the dynamic behavior. Empirical relations are needed for the static behavior based on numerical test observations. The dynamic behavior for both dense and loose packing can be given by analytical relations. Cosserat continuum theory is needed to derive relations for Vp and Vs. It is shown that by constraining the particle rotation, the S-wave velocity can be

  14. Copper avoidance and mortality of juvenile brown trout (Salmo trutta) in tests with copper-sulfate-treated water from West Branch Reservoir, Putnam County, New York (United States)

    Baldigo, Barry P.; Baudanza, T.P.


    Copper-avoidance tests and acute-toxicity (mortality) tests on hatchery-reared, young-of- the-year brown trout (salmo trutta) were conducted with water from West Branch Reservoir to assess the avoidance response to copper sulfate treatment, which is used occasionally by New York City Department of Environmental Protection to decrease phytoplankton populations in the reservoir. Avoidance-test results indicate that juvenile brown trout tend to avoid dissolved copper concentrations greater than about 55 μg/L (micrograms per liter), which is the approximate avoidance-response threshold. The mean net avoidance response of brown trout to dissolved copper concentrations of 70 and 100 μg/L, and possibly 80 μg/L, was significantly different (at α= 0.1) from the mean net avoidance response of fish to control (untreated) water and to treated water at most other tested concentrations. Mortality-test results indicate that the 96-hr median lethal concentration (LC50) of dissolved copper was 61.5 μg/L. All (100 percent) of the brown trout died at a dissolved copper concentration of 85 μg/L, many died at concentrations of 62 μg/L and 70 μg/L, and none died in the control waters (7 μg/L) or at concentrations of 10, 20, or 45 μg/L. The estimated concentration of dissolved copper that caused fish mortality (threshold) was 53.5 μg/L, virtually equivalent to the avoidance-response threshold.Additional factors that could affect the copper-avoidance and mortality response of individual brown trout and their populations in West Branch Reservoir include seasonal variations in certain water-quality parameters, copper-treatment regimes, natural fish distributions during treatment, and increased tolerance due to acclimation. These warrant additional study before the findings from this study can be used to predict the effects that copper sulfate treatments have on resident fish populations in New York City reservoirs.

  15. The study of permeabilities, measured at various scales, of a fluviatile sandstone reservoir. Development and application of a well test numerical simulator; Etude des permeabilites mesurees a differentes echelles d`un reservoir greseux fluviatile. Developpement et application d`un simulateur numerique de tests de puits

    Energy Technology Data Exchange (ETDEWEB)

    Jacquin, T.


    The general problem of a single phase fluid flow through heterogenous porous media, is studied, focusing on well test data interpretation in the context of reservoir characterization; a 3D finite volume code, with capacity of local refinement, is developed to simulate well tests. After a review of traditional techniques used to interpret well test data, and their extension to heterogenous media using a weighting function that depends upon the flow geometry, an analysis is carried out for 2D correlated lognormal permeability distributions: it compares well to numerical well tests performed on low variance permeability distributions but needs further investigation for high variance. For 3D heterogenous permeability fields, well bore pressure cannot be estimated by analytical means; therefore a more empirical approach is used to study the permeability field of a reservoir used by Gaz de France as an underground gas storage. Simulated well tests are performed on a reservoir model based upon core measurements and log analysis. The numerical investigation reveals inconsistencies in the treatment of available data, which can be corrected so geology is better taken into account

  16. Amplitude various angles (AVA) phenomena in thin layer reservoir: Case study of various reservoirs

    International Nuclear Information System (INIS)

    thfloor, Physics Dept., FMIPA, Institut Teknologi Bandung (Indonesia); Rock Fluid Imaging Lab., Bandung (Indonesia))" data-affiliation=" (Wave Inversion and Subsurface Fluid Imaging Research Laboratory (WISFIR), Basic Science Center A 4thfloor, Physics Dept., FMIPA, Institut Teknologi Bandung (Indonesia); Rock Fluid Imaging Lab., Bandung (Indonesia))" >Nurhandoko, Bagus Endar B.; Susilowati


    Amplitude various offset is widely used in petroleum exploration as well as in petroleum development field. Generally, phenomenon of amplitude in various angles assumes reservoir’s layer is quite thick. It also means that the wave is assumed as a very high frequency. But, in natural condition, the seismic wave is band limited and has quite low frequency. Therefore, topic about amplitude various angles in thin layer reservoir as well as low frequency assumption is important to be considered. Thin layer reservoir means the thickness of reservoir is about or less than quarter of wavelength. In this paper, I studied about the reflection phenomena in elastic wave which considering interference from thin layer reservoir and transmission wave. I applied Zoeppritz equation for modeling reflected wave of top reservoir, reflected wave of bottom reservoir, and also transmission elastic wave of reservoir. Results show that the phenomena of AVA in thin layer reservoir are frequency dependent. Thin layer reservoir causes interference between reflected wave of top reservoir and reflected wave of bottom reservoir. These phenomena are frequently neglected, however, in real practices. Even though, the impact of inattention in interference phenomena caused by thin layer in AVA may cause inaccurate reservoir characterization. The relation between classes of AVA reservoir and reservoir’s character are different when effect of ones in thin reservoir and ones in thick reservoir are compared. In this paper, I present some AVA phenomena including its cross plot in various thin reservoir types based on some rock physics data of Indonesia

  17. Numerical modeling of self-limiting and self-enhancing caprock alteration induced by CO2 storage in a depleted gas reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Tianfu; Gherardi, Fabrizio; Xu, Tianfu; Pruess, Karsten


    This paper presents numerical simulations of reactive transport which may be induced in the caprock of an on-shore depleted gas reservoir by the geological sequestration of carbon dioxide. The objective is to verify that CO{sub 2} geological disposal activities currently being planned for the study area are safe and do not induce any undesired environmental impact. In our model, fluid flow and mineral alteration are induced in the caprock by penetration of high CO{sub 2} concentrations from the underlying reservoir, where it was assumed that large amounts of CO{sub 2} have already been injected at depth. The main focus is on the potential effect of precipitation and dissolution processes on the sealing efficiency of caprock formations. Concerns that some leakage may occur in the investigated system arise because the seal is made up of potentially highly-reactive rocks, consisting of carbonate-rich shales (calcite+dolomite averaging up to more than 30% of solid volume fraction). Batch simulations and multi-dimensional 1D and 2D modeling have been used to investigate multicomponent geochemical processes. Numerical simulations account for fracture-matrix interactions, gas phase participation in multiphase fluid flow and geochemical reactions, and kinetics of fluid-rock interactions. The geochemical processes and parameters to which the occurrence of high CO{sub 2} concentrations are most sensitive are investigated by conceptualizing different mass transport mechanisms (i.e. diffusion and mixed advection+diffusion). The most relevant mineralogical transformations occurring in the caprock are described, and the feedback of these geochemical processes on physical properties such as porosity is examined to evaluate how the sealing capacity of the caprock could evolve in time. The simulations demonstrate that the occurrence of some gas leakage from the reservoir may have a strong influence on the geochemical evolution of the caprock. In fact, when a free CO{sub 2

  18. Tenth workshop on geothermal reservoir engineering: proceedings

    Energy Technology Data Exchange (ETDEWEB)


    The workshop contains presentations in the following areas: (1) reservoir engineering research; (2) field development; (3) vapor-dominated systems; (4) the Geysers thermal area; (5) well test analysis; (6) production engineering; (7) reservoir evaluation; (8) geochemistry and injection; (9) numerical simulation; and (10) reservoir physics. (ACR)

  19. Experiments to test an intra-island scoop limiter on TEXT

    International Nuclear Information System (INIS)

    Evans, T.E.; DeGrassie, J.S.; Jackson, G.L.; Ohyabu, N.; Wootton, A.J.; Gentle, K.W.; Hodge, W.L.; McCool, S.C.; Phillips, P.E.; Rhodes, T.L.; Richards, B.; Ritz, C.P.; Rowan, W.L.


    An instrumented scoop limiter probe is being operated on TEXT to test the concept of limiter cooling and improved particle removal efficiencies using an externally-applied resonant magnetic field perturbation (the resonant helical divertor concept). Cooling of the limiter face has been demonstrated for limiter positions ranging from r L = 29.0 cm inward to r L = 25.5 cm (the TEXT primary poloidal hoop limiter radius r a = 27.0 cm). Pressure rises in the limiter throat of approximately 40% are observed under optimized conditions. Interchangable limiter heads with thicknesses of 1.0 cm and 0.3 cm have been used to examine particle ducting into the scoop aperture. Experimental results are discussed along with observations of the limiter floating potential, H α recycling emissions, pressure measurements, and edge density and temperature measurements. (orig.)

  20. Experiments to test an intra-island scoop limiter on TEXT

    International Nuclear Information System (INIS)

    Evans, T.E.; deGrassie, J.S.; Jackson, G.L.; Ohyabu, N.; Karger, F.; Haas, G.


    An instrumented scoop limiter probe is being operated on TEXT to test the concept of limiter cooling and improved particle removal efficiencies using an externally-applied resonant magnetic field perturbation (the resonant helical divertor concept). Cooling of the limiter face has been demonstrated for limiter positions ranging from γ/sub L/ = 29.0 cm inward to γ/sub L/ = 25.5 cm (the TEXT primary poloidal hoop limiter radius γ/sub a/ = 27.0 cm). Pressure rises in the limiter throat of approximately 40% are observed under optimized conditions. Interchangeable limiter heads with thicknesses of 1.0 cm and 0.3 cm have been used to examine particle ducting into the scoop aperture. Experimental results are discussed along with observations of the limiter floating potential, H/sub α/ recycling emissions, pressure measurements, and edge density and temperature measurements


    Energy Technology Data Exchange (ETDEWEB)

    Lam, P.S.; Morgan, M.J


    The burst test is used to assess the material performance of tritium reservoirs in the surveillance program in which reservoirs have been in service for extended periods of time. A materials system model and finite element procedure were developed under a Savannah River Site Plant-Directed Research and Development (PDRD) program to predict the structural response under a full range of loading and aged material conditions of the reservoir. The results show that the predicted burst pressure and volume ductility are in good agreement with the actual burst test results for the unexposed units. The material tensile properties used in the calculations were obtained from a curved tensile specimen harvested from a companion reservoir by Electric Discharge Machining (EDM). In the absence of exposed and aged material tensile data, literature data were used for demonstrating the methodology in terms of the helium-3 concentration in the metal and the depth of penetration in the reservoir sidewall. It can be shown that the volume ductility decreases significantly with the presence of tritium and its decay product, helium-3, in the metal, as was observed in the laboratory-controlled burst tests. The model and analytical procedure provides a predictive tool for reservoir structural integrity under aging conditions. It is recommended that benchmark tests and analysis for aged materials be performed. The methodology can be augmented to predict performance for reservoir with flaws.

  2. Human Factors Assessment of the UH-60M Crew Station During the Limited User Test (LUT)

    National Research Council Canada - National Science Library

    Havir, Thomas J; Durbin, David B; Frederick, Lorraine J; Hicks, Jamison S


    The utility helicopter (UH)-60M Product Manager requested the U.S. Army Research Laboratory's Human Research and Engineering Directorate to participate in the Limited User Test for the UH-60M Black Hawk...

  3. On the limits of toxicant-induced tolerance testing: cotolerance and response variation of antibiotic effects.

    NARCIS (Netherlands)

    Schmitt, Heike; Martinali, Bennie; Beelen, Patrick van; Seinen, Willem


    Pollution-induced community tolerance (PICT) as an ecotoxicological test system has been claimed to detect pollutant effects highly specifically and sensitively. However, the specificity might be limited by the occurrence of cotolerance. Another limitation of the application of any ecotoxicological

  4. Comparison of two standard test methods for determining explosion limits of gases at atmospheric conditions. (United States)

    De Smedt, G; de Corte, F; Notelé, R; Berghmans, J


    A comparison is made between two internationally accepted methods to determine the explosion limits of gases at atmospheric pressure and room temperature (20 l sphere - DIN 51649). Significant differences (about 1 vol.%) in the upper explosion limits (UEL) values are found for four hydrocarbons tested. A new criterion is proposed which leads to close agreement between the UEL values obtained by the two methods.

  5. Enhancement of seismic monitoring in hydrocarbon reservoirs (United States)

    Caffagni, Enrico; Bokelmann, Götz


    Hydraulic Fracturing (HF) is widely considered as one of the most significant enablers of the successful exploitation of hydrocarbons in North America. Massive usage of HF is currently adopted to increase the permeability in shale and tight-sand deep reservoirs, despite the economical downturn. The exploitation success is less due to the subsurface geology, but in technology that improves exploration, production, and decision-making. This includes monitoring of the reservoir, which is vital. Indeed, the general mindset in the industry is to keep enhancing seismic monitoring. It allows understanding and tracking processes in hydrocarbon reservoirs, which serves two purposes, a) to optimize recovery, and b) to help minimize environmental impact. This raises the question of how monitoring, and especially seismic techniques could be more efficient. There is a pressing demand from seismic service industry to evolve quickly and to meet the oil-gas industry's changing needs. Nonetheless, the innovative monitoring techniques, to achieve the purpose, must enhance the characterization or the visualization of a superior-quality images of the reservoir. We discuss recent applications of seismic monitoring in hydrocarbon reservoirs, detailing potential enhancement and eventual limitations. The aim is to test the validity of these seismic monitoring techniques, qualitatively discuss their potential application to energy fields that are not only limited to HF. Outcomes from our investigation may benefit operators and regulators in case of future massive HF applications in Europe, as well. This work is part of the FracRisk consortium (, funded by the Horizon2020 research programme, whose aims is to help minimize the environmental footprint of the shale-gas exploration and exploitation.

  6. Reservoir microseismicity at the Ekofisk Oil Field

    Energy Technology Data Exchange (ETDEWEB)

    Rutledge, J.T.; Fairbanks, T.D. [Nambe Geophysical, Inc., Santa Fe, NM (United States); Albright, J.N. [Los Alamos National Lab., NM (United States); Boade, R.R. [Phillips Petroleum Co., Bartlesville, OK (United States); Dangerfield, J.; Landa, G.H. [Phillips Petroleum Co., Tananger (Norway)


    A triaxial, downhole geophone was deployed within the Ekofisk oil reservoir for monitoring ambient microseismicity as a test to determine if microearthquake signals generated from discrete shear failure of the reservoir rock could be detected. The results of the test were positive. During 104 hours of monitoring, 572 discrete events were recorded which have been identified as shear-failure microearthquakes. Reservoir microseismicity was detected at large distances (1000 m) from the monitor borehole and at rates (> 5 events per hour) which may allow practical characterization of the reservoir rock and overburden deformation induced by reservoir pressure changes.

  7. Most experiments done so far with limited plants. Large-scale testing ...

    Indian Academy of Sciences (India)

    First page Back Continue Last page Graphics. Most experiments done so far with limited plants. Large-scale testing needs to be done with objectives such as: Apart from primary transformants, their progenies must be tested. Experiments on segregation, production of homozygous lines, analysis of expression levels in ...

  8. High Speed Vessel Medical Limited Objective Experiment, Noise Assessment and Noise Reducing Stethoscope Field Test

    National Research Council Canada - National Science Library

    Russotti, Joseph S; Duplessis, Christopher


    .... This Medical Limited Objective Experiment (LOE) was valuable both to evaluate the noise environment in spaces not designed for habitation, and to simultaneously test a pre-production noise-reducing stethoscope. In controlled setting under operationally-relevant shipboard noise conditions in the field tests, the noise-reducing stethoscope proved to be significant, substantial improvement over a conventional sound-powered device.

  9. G. M. Koelemay well No. 1, Jefferson County, Texas. Volume I. Completion and testing: testing geopressured geothermal reservoirs in existing wells. Final report

    Energy Technology Data Exchange (ETDEWEB)


    The acquisition, completion, and testing of a geopressured-geothermal well are described. The following are covered: geology; petrophysics; re-entry and completion operations - test well; drilling and completion operations - disposal well; test objectives; surface testing facilities; pre-test operations; test sequence; test results and analysis; and return of wells and location to operator. (MHR)

  10. Plant cover, soil temperature, freeze, water stress, and evapotranspiration conditions. [Lower Rio Grande Valley Test Site: Weslaco, Texas; Falco Reservoir and the Gulf of Mexico (United States)

    Wiegand, C. L.; Nixon, P. R.; Gausman, H. W.; Namken, L. N.; Leamer, R. W.; Richardson, A. J. (Principal Investigator)


    The author has identified the following significant results. HCMM day/night coverage 12 hours apart cannot be obtained at 26 deg N latitude; nor have any pairs 36 hours apart been obtained. A day-IR scene and a night scene for two different dates were analyzed. A profile across the test site for the same latitude shows that the two profiles are near mirror images of each other over land surfaces and that the temperature of two large water bodies, Falcon Reservoir and the Gulf of Mexico, are nearly identical on two dates. During the time interval between overpasses, the vegetative cover remained static due to winter dormancy. The data suggest that day/night temperature differences measured weeks apart may yield meaningful information about the contrast between daytime maximum and nighttime minimum temperatures for a given site.

  11. Monte Carlo reservoir analysis combining seismic reflection data and informed priors

    DEFF Research Database (Denmark)

    Zunino, Andrea; Mosegaard, Klaus; Lange, Katrine


    Determination of a petroleum reservoir structure and rock bulk properties relies extensively on inference from reflection seismology. However, classic deterministic methods to invert seismic data for reservoir properties suffer from some limitations, among which are the difficulty of handling...... with the goal to directly infer the rock facies and porosity of a target reservoir zone. We thus combined a rock-physics model with seismic data in a single inversion algorithm. For large data sets, theMcMC method may become computationally impractical, so we relied on multiple-point-based a priori information...... to quantify geologically plausible models. We tested this methodology on a synthetic reservoir model. The solution of the inverse problem was then represented by a collection of facies and porosity reservoir models, which were samples of the posterior distribution. The final product included probability maps...

  12. Proposal of concentration limits for determining the hazard property HP 14 for waste using ecotoxicological tests. (United States)

    Hennebert, Pierre


    Different ecotoxicological test batteries and concentration limits have been proposed to assess the hazard property (HP) HP 14 'Ecotoxic' for waste in the European Union and its member states. In test batteries, if the concentration of waste in the culture/dilution medium producing 50% of inhibitory biological effect in one or more test(s) is below the concentration limit of the test, the waste is classified as hazardous. A summarized review of the test batteries proposed since 1998 is presented. The last proposed test battery uses seven aquatic and terrestrial species with standardized methods, but with options and uniform concentration limits of 10% of waste eluate or solid waste in the culture/dilution medium. No attempt was made to match this hazard assessment with the classification made in the European List of Waste (LoW). The aim of this paper is to propose for the same test battery (reduced to 6 tests without options) concentration limits that match with the European List of Waste. This list was taken as reference (despite the fact that waste can be hazardous for other properties than the most frequent HP 14, and its partly political nature for some opinions). The concentration limits (CLs) for tests are the concentrations producing the highest ecotoxicological effects for each test observed in a non-hazardous waste set. Data from Germany, France and Belgium (from in total 5 different sources from 2009 to 2016) with the above-mentioned test battery (without options) were gathered for 81 samples, being the largest set ever published. In total, ten non-hazardous (NH) waste samples (as defined by the LoW and for most of them checked by chemical composition) were used to establish CLs. These CLs were then applied to 13 hazardous (H) waste by the LoW, and all were classified as hazardous. The matching of the resulting classification with the LoW is convincing. For the 58 'mirror entries' in the LoW (hazardous or not depending of the presence of hazardous

  13. Force Limiting Vibration Tests Evaluated from both Ground Acoustic Tests and FEM Simulations of a Flight Like Vehicle System Assembly (United States)

    Smith, Andrew; LaVerde, Bruce; Waldon, James; Hunt, Ron


    Marshall Space Flight Center has conducted a series of ground acoustic tests with the dual goals of informing analytical judgment, and validating analytical methods when estimating vibroacoustic responses of launch vehicle subsystems. The process of repeatedly correlating finite element-simulated responses with test-measured responses has assisted in the development of best practices for modeling and post-processing. In recent work, force transducers were integrated to measure interface forces at the base of avionics box equipment. Other force data was indirectly measured using strain gauges. The combination of these direct and indirect force measurements has been used to support and illustrate the advantages of implementing the Force Limiting approach for equipment qualification tests. The comparison of force response from integrated system level tests to measurements at the same locations during component level vibration tests provides an excellent illustration. A second comparison of the measured response cases from the system level acoustic tests to finite element simulations has also produced some principles for assessing the suitability of Finite Element Models (FEMs) for making vibroacoustics estimates. The results indicate that when FEM models are employed to guide force limiting choices, they should include sufficient detail to represent the apparent mass of the system in the frequency range of interest.

  14. Determine ISS Soyuz Orbital Module Ballistic Limits for Steel Projectiles Hypervelocity Impact Testing (United States)

    Lyons, Frankel


    A new orbital debris environment model (ORDEM 3.0) defines the density distribution of the debris environment in terms of the fraction of debris that are low-density (plastic), medium-density (aluminum) or high-density (steel) particles. This hypervelocity impact (HVI) program focused on assessing ballistic limits (BLs) for steel projectiles impacting the enhanced Soyuz Orbital Module (OM) micrometeoroid and orbital debris (MMOD) shield configuration. The ballistic limit was defined as the projectile size on the threshold of failure of the OM pressure shell as a function of impact speeds and angle. The enhanced OM shield configuration was first introduced with Soyuz 30S (launched in May 2012) to improve the MMOD protection of Soyuz vehicles docked to the International Space Station (ISS). This test program provides HVI data on U.S. materials similar in composition and density to the Russian materials for the enhanced Soyuz OM shield configuration of the vehicle. Data from this test program was used to update ballistic limit equations used in Soyuz OM penetration risk assessments. The objective of this hypervelocity impact test program was to determine the ballistic limit particle size for 440C stainless steel spherical projectiles on the Soyuz OM shielding at several impact conditions (velocity and angle combinations). This test report was prepared by NASA-JSC/ HVIT, upon completion of tests.

  15. Reservoir engineering studies of the Gladys McCall geopressured-geothermal resource. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lea, C.M.; Lee, K.; Miller, M.A.


    Transient pressure analysis techniques have been used to evaluate the performance of the Gladys McCall geopressured-geothermal reservoir. A fault-controlled aquifer influx model has also been developed to account for pressure support observed during both reservoir depletion and recovery phases. The Gladys McCall No. 1 well was drilled and completed in the lower Miocene geopressured sandstones under the US Department of energy geopressured-geothermal research program. The well was shut in october 1987 after producing over 27 MMstb of brine and 676 MMscf gas since October 1983. Eight pressure transient tests were conducted in the well. Analysis of transient pressure data provided a quantitative evaluation of reservoir characteristics, including: (a) formation transmissibility and skin, (b) the size and possible shape of the main producing reservoir, (c) characteristics of the pressure support mechanism. The pressure behavior of 1983 Reservoir Limits Test (RLT) suggested that the Gladys McCall reservoir might have a long narrow shape with the well located off-center. An elongated numerical model developed accordingly was able to reproduce the pressure characteristics show in the test. During both the reservoir production and shut-in periods, pressure buildup tests indicated some degree of external pressure support. Aquifer recharging was believed to be the main source. Based on reservoir material-balance calculations, an aquifer influx model was derived from a conceptual model of water leakage through a partially sealing fault into the reservoir under steady-state conditions. Moreover, a match of the pressure history required that the conductivity of the fault be a function of the pressure difference between the supporting aquifer and the reservoir.

  16. Reservoir engineering studies of the Gladys McCall geopressured-geothermal resource; Final report

    Energy Technology Data Exchange (ETDEWEB)

    Chen-Min; Less, K.; Miller, M.A.


    Transient pressure analysis techniques have been used to evaluate the performance of the Gladys McCall geopressured-geothermal reservoir. A fault-controlled aquifer influx model has also been developed to account for pressure support observed during both reservoir depletion and recovery phases. The Gladys McCall No. 1 well was drilled and completed in the lower Miocene geopressured sandstones under the US Department of Energy geopressured-geothermal research program. The well was shut in October 1987 after producing over 27 MMstb of brine and 676 MMscf gas since October 1983. Eight pressure transient tests were conducted in the well. Analysis of transient pressure data provided a quantitative evaluation of reservoir characteristics, including: (a) formation transmissibility and skin, (b) the size and possible shape of the main producing reservoir, and (c) characteristics of the pressure support mechanism. The pressure behavior of 1983 Reservoir Limits Test (RLT) suggested that the Gladys McCall reservoir might have a long narrow shape with the well located off-center. An elongated numerical model developed accordingly was able to reproduce the pressure characteristics shown in the test. During both the reservoir production and shut-in periods, pressure buildup tests indicated some degree of external pressure support. Aquifer recharging was believed to be the main source. Based on reservoir material-balance calculations, an aquifer influx model was derived from a conceptual model of water leakage through a partially sealing fault into the reservoir under steady-state conditions. Moreover, a match of the pressure history required that the conductivity of the fault be a function of the pressure difference between the supporting aquifer and the reservoir.

  17. Central limit theorems for classical likelihood ratio tests for high-dimensional normal distributions


    Jiang, Tiefeng; Yang, Fan


    For random samples of size $n$ obtained from $p$-variate normal distributions, we consider the classical likelihood ratio tests (LRT) for their means and covariance matrices in the high-dimensional setting. These test statistics have been extensively studied in multivariate analysis, and their limiting distributions under the null hypothesis were proved to be chi-square distributions as $n$ goes to infinity and $p$ remains fixed. In this paper, we consider the high-dimensional case where both...

  18. Production test IP-725, increased graphite temperature limit, F Reactor. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Russell, A.


    This report presents the results of a high graphite temperature test conducted at F Reactor from January, through June, 1965. Since the reactor was soon to be permanently shut down, this was believed to be a good opportunity to investigate the effect of increased graphite temperature on graphite stack oxidation with CO{sub 2}, During the first phase of the test, the graphite temperature limit was increased, from 650 C to 700 C for a period of approximately 3 1/2 months. During this phase of the test the actual maximum operating graphite temperature was maintained near the 700 C limit. During the second phase of the test the temperature limit was further increased to 750 C for approximately 2 months. Unfortunately,, the actual graphite operating temperature was maintained at the desired temperature level for only several weeks and thus complicated interpretation of the test results. Throughout the 6 month test period, stack oxidation was monitored with graphite samples inserted in 2 bare process tube channels and by measurement of CO (reaction product of graphite and CO{sub 2}) in the reactor gas atmosphere.

  19. Colleges Eye Limit on Time Players Give to Sports, Tougher Tests for Drug Abuse. (United States)

    Farrell, Charles S.


    The death of a basketball player at the University of Maryland is giving new impetus to proposals to toughen the testing of athletes for drugs and to tighten limits on the time college players devote to their sports. Developments at Maryland and the National Collegiate Athletic Association are described. (MLW)

  20. Laboratory evaluation of the improved tube test detection limits for β ...

    African Journals Online (AJOL)


    Key words: Improved tube test, β-lactams, Kenyan milk, maximum residue limits. INTRODUCTION. Antibiotics residues in bovine milk are a problem in. Kenyan milk (Ombui et al., 1995; Shitandi and Sternesjö,. 2001). The β-lactam group of antimicrobials are in particular commonly utilised in lactating animals (Mandell.

  1. Detection of alloreactive T cells by flow cytometry : A new test compared with limiting dilution assay

    NARCIS (Netherlands)

    de Haan, A; van der Gun, [No Value; van der Bij, W; de Leij, LFMH; Prop, J


    Background. Frequencies of alloreactive T cells determined by limiting dilution assays (LDA) may not adequately reflect the donor-reactive immune status in transplant recipients. To reevaluate LDA frequencies, we developed a flow cytometry test for direct determination of alloreactive T-cell

  2. Time limits in testing: An analysis of eye movements and visual attention in spatial problem solving. (United States)

    Roach, Victoria A; Fraser, Graham M; Kryklywy, James H; Mitchell, Derek G V; Wilson, Timothy D


    Individuals with an aptitude for interpreting spatial information (high mental rotation ability: HMRA) typically master anatomy with more ease, and more quickly, than those with low mental rotation ability (LMRA). This article explores how visual attention differs with time limits on spatial reasoning tests. Participants were assorted to two groups based on their mental rotation ability scores and their eye movements were collected during these tests. Analysis of salience during testing revealed similarities between MRA groups in untimed conditions but significant differences between the groups in the timed one. Question-by-question analyses demonstrate that HMRA individuals were more consistent across the two timing conditions (κ = 0.25), than the LMRA (κ = 0.013). It is clear that the groups respond to time limits differently and their apprehension of images during spatial problem solving differs significantly. Without time restrictions, salience analysis suggests LMRA individuals attended to similar aspects of the images as HMRA and their test scores rose concomitantly. Under timed conditions however, LMRA diverge from HMRA attention patterns, adopting inflexible approaches to visual search and attaining lower test scores. With this in mind, anatomical educators may wish to revisit some evaluations and teaching approaches in their own practice. Although examinations need to evaluate understanding of anatomical relationships, the addition of time limits may induce an unforeseen interaction of spatial reasoning and anatomical knowledge. Anat Sci Educ 10: 528-537. © 2017 American Association of Anatomists. © 2017 American Association of Anatomists.

  3. Aquatic toxicity testing of liquid hydrophobic chemicals – Passive dosing exactly at the saturation limit

    DEFF Research Database (Denmark)

    Stibany, Felix; Nørgaard Schmidt, Stine; Schäffer, Andreas


    The aims of the present study were (1) to develop a passive dosing approach for aquatic toxicity testing of liquid substances with very high Kow values and (2) to apply this approach to the model substance dodecylbenzene (DDB, Log Kow = 8.65). The first step was to design a new passive dosing...... format for testing DDB exactly at its saturation limit. Silicone O-rings were saturated by direct immersion in pure liquid DDB, which resulted in swelling of >14%. These saturated O-rings were used to establish and maintain DDB exposure exactly at the saturation limit throughout 72-h algal growth...... at chemical activity of unity was higher than expected relative to a reported hydrophobicity cut-off in toxicity, but lower than expected relative to a reported chemical activity range for baseline toxicity. The present study introduces a new effective approach for toxicity testing of an important group...

  4. Public attitudes toward ancillary information revealed by pharmacogenetic testing under limited information conditions. (United States)

    Haga, Susanne B; O'Daniel, Julianne M; Tindall, Genevieve M; Lipkus, Isaac R; Agans, Robert


    Pharmacogenetic testing can inform drug dosing and selection by aiding in estimating a patient's genetic risk of adverse response and/or failure to respond. Some pharmacogenetic tests may generate ancillary clinical information unrelated to the drug treatment question for which testing is done-an informational "side effect." We aimed to assess public interest and concerns about pharmacogenetic tests and ancillary information. We conducted a random-digit-dial phone survey of a sample of the US public. We achieved an overall response rate of 42% (n = 1139). When the potential for ancillary information was presented, 85% (±2.82%) of respondents expressed interest in pharmacogenetic testing, compared with 82% (±3.02%) before discussion of ancillary information. Most respondents (89% ± 2.27%) indicated that physicians should inform patients that a pharmacogenetic test may reveal ancillary risk information before testing is ordered. Respondents' interest in actually learning of the ancillary risk finding significantly differed based on disease severity, availability of an intervention, and test validity, even after adjusting for age, gender, education, and race. Under the limited information conditions presented in the survey, the potential of ancillary information does not negatively impact public interest in pharmacogenetic testing. Interest in learning ancillary information is well aligned with the public's desire to be informed about potential benefits and risks before testing, promoting patient autonomy.

  5. HIV self-testing in resource-limited settings: regulatory and policy considerations. (United States)

    Wong, Vincent; Johnson, Cheryl; Cowan, Elliot; Rosenthal, Matthew; Peeling, Rosanna; Miralles, Maria; Sands, Anita; Brown, Charlene


    HIV self-testing (HIVST) is an emerging HIV testing strategy intended to address challenges of increasing access to preliminary knowledge of serostatus. It offers the potential for tests and testing to reach more people than previously possible, including those who do not seek testing in facilities. With approval of an HIV self-test kit in the USA, increasing evidence from public pilot programs in sub-Saharan Africa showing high acceptability and feasibility, and evidence of the informal sale of rapid HIV test kits in the private sector, options for individuals to access HIV self-testing, as well as consumer-demand, appear to be increasing. More recently WHO and UNAIDS have explored self-testing as an option to achieving greater HIV testing coverage to support global treatment targets. However, for resource-limited settings, technological development, diagnostic device regulation and quality assurance policies are lagging behind. This commentary will examine regulatory and policy issues with HIVST, given its increased prominence as a potential part of the global HIV/AIDS response.

  6. Assaying embryotoxicity in the test tube: current limitations of the embryonic stem cell test (EST) challenging its applicability domain. (United States)

    Riebeling, Christian; Hayess, Katrin; Peters, Annelieke K; Steemans, Margino; Spielmann, Horst; Luch, Andreas; Seiler, Andrea E M


    Testing for embryotoxicity in vitro is an attractive alternative to animal experimentation. The embryonic stem cell test (EST) is such a method, and it has been formally validated by the European Centre for the Validation of Alternative Methods. A number of recent studies have underscored the potential of this method. However, the EST performed well below the 78% accuracy expected from the validation study using a new set of chemicals and pharmaceutical compounds, and also of toxicity criteria, tested to enlarge the database of the validated EST as part of the Work Package III of the ReProTect Project funded within the 6th Framework Programme of the European Union. To assess the performance and applicability domain of the EST we present a detailed review of the substances and their effects in the EST being nitrofen, ochratoxin A, D-penicillamine, methylazoxymethanol, lovastatin, papaverine, warfarin, β-aminopropionitrile, dinoseb, furosemide, doxylamine, pravastatin, and metoclopramide. By delineation of the molecular mechanisms of the substances we identify six categories of reasons for misclassifications. Some of these limitations might also affect other in vitro methods assessing embryotoxicity. Substances that fall into these categories need to be included in future validation sets and in validation guidelines for embryotoxicity testing. Most importantly, we suggest conceivable improvements and additions to the EST which will resolve most of the limitations.

  7. Pulmonary artery wave propagation and reservoir function in conscious man: impact of pulmonary vascular disease, respiration and dynamic stress tests

    DEFF Research Database (Denmark)

    Su, Junjing; Manisty, Charlotte; Simonsen, Ulf


    and dynamic stress tests. Right heart catheterization was performed using a pressure and Doppler flow sensor tipped guidewire to obtain simultaneous pressure and flow velocity measurements in the pulmonary artery in control subjects and patients with pulmonary arterial hypertension (PAH) at rest. In controls...

  8. Phenotyping Exercise Limitation in Systemic Sclerosis: The Use of Cardiopulmonary Exercise Testing. (United States)

    Boutou, Afroditi K; Pitsiou, Georgia G; Siakka, Panagiota; Dimitroulas, Theodoros; Paspala, Asimina; Sourla, Evdokia; Chavouzis, Nikolaos; Garyfallos, Alexandros; Argyropoulou, Paraskevi; Stanopoulos, Ioannis


    Exercise impairment is a common symptom of systemic sclerosis (SSc), a disorder which is frequently complicated by cardiopulmonary involvement. This study's aims were: (a) to define the prevalence and the potential causes of limited exercise capacity and (b) to study potential differences in clinical, radiological and functional characteristics and blood serology among SSc patients with exercise limitation of different etiology. Prospectively collected data on SSc patients who had conducted full lung function testing, blood serology, thorax high-resolution computed tomography, Doppler echocardiogram and a maximal cardiopulmonary exercise testing (CPET) were retrospectively analyzed. Using a CPET algorithm, patients were characterized as having normal or subnormal exercise capacity (N), respiratory limitation (RL), left ventricular dysfunction (LVD) or pulmonary vasculopathy (PV). Group comparisons were conducted using either one-way ANOVA or the Kruskal-Wallis test. A p value present in 32.1%, LVD in 25.6% and RL in 10.2%, while 32.1% of the patients constituted the N group. The presence of antisclero-70 antibodies, low anaerobic threshold and low peak exercise capacity measures could discriminate LVD from the other groups. Low end-tidal carbon dioxide pressure and its change from rest to anaerobic threshold could discriminate between the PV, LVD and N groups, while respiratory restriction along with ventilatory inefficiency indices could differentiate the RL group from the rest. The combined evaluation of CPET gas exchange patterns with baseline measurements could discriminate the causes of exercise limitation among SSc patients. © 2016 S. Karger AG, Basel.

  9. Flaring and venting review of well test time limits : final report

    Energy Technology Data Exchange (ETDEWEB)



    The Clean Air Strategic Alliance (CASA) is a non-profit association composed of stakeholders from government, industry and non-government organizations such as health and environment groups. In September 2004, the CASA board approved recommendations put forward by their Flaring and Venting Project Team (FVPT) regarding well test flare management. It was noted that the FVPT has agreed that different flare durations will be needed for oil, gas and coalbed methane (CBM) production. Oil and gas well test flaring and venting should be limited to a total period of 72 hours per zone tested, with special exemptions for cleaning up well bores in unique situations. It was suggested the Energy and Utilities Board (EUB) should be contacted if additional flaring and venting time was needed and that flaring and venting must be discontinued when well test information indicated that clean up was complete and well flow was stabilized. Recommendations for dry coalbed methane were also included. The collected data did not include any wet CBM, as these need dewatering for several months to determine if the well is commercially viable. The FVPT also recommended that the EUB review its well test requirements by 2006, to see if flaring and venting from well tests can be further reduced. The FVPT suggested that the EUB should audit 15 per cent of wells exceeding the stated time limits. It was recommended that the FVPT also review the audit data when it reconvenes in the first quarter of 2007. refs., tabs., figs.

  10. Well Test Analysis of Naturally Fractured Vuggy Reservoirs with an Analytical Triple Porosity – Double Permeability Model and a Global Optimization Method

    Directory of Open Access Journals (Sweden)

    Gómez Susana


    Full Text Available The aim of this work is to study the automatic characterization of Naturally Fractured Vuggy Reservoirs via well test analysis, using a triple porosity-dual permeability model. The inter-porosity flow parameters, the storativity ratios, as well as the permeability ratio, the wellbore storage effect, the skin and the total permeability will be identified as parameters of the model. In this work, we will perform the well test interpretation in Laplace space, using numerical algorithms to transfer the discrete real data given in fully dimensional time to Laplace space. The well test interpretation problem in Laplace space has been posed as a nonlinear least squares optimization problem with box constraints and a linear inequality constraint, which is usually solved using local Newton type methods with a trust region. However, local methods as the one used in our work called TRON or the well-known Levenberg-Marquardt method, are often not able to find an optimal solution with a good fit of the data. Also well test analysis with the triple porosity-double permeability model, like most inverse problems, can yield multiple solutions with good match to the data. To deal with these specific characteristics, we will use a global optimization algorithm called the Tunneling Method (TM. In the design of the algorithm, we take into account issues of the problem like the fact that the parameter estimation has to be done with high precision, the presence of noise in the measurements and the need to solve the problem computationally fast. We demonstrate that the use of the TM in this study, showed to be an efficient and robust alternative to solve the well test characterization, as several optimal solutions, with very good match to the data were obtained.

  11. Discrete Element Modeling of Micro-scratch Tests: Investigation of Mechanisms of CO2 Alteration in Reservoir Rocks (United States)

    Sun, Zhuang; Espinoza, D. Nicolas; Balhoff, Matthew T.; Dewers, Thomas A.


    The injection of CO2 into geological formations leads to geochemical re-equilibrium between the pore fluid and rock minerals. Mineral-brine-CO2 reactions can induce alteration of mechanical properties and affect the structural integrity of the storage formation. The location of alterable mineral phases within the rock skeleton is important to assess the potential effects of mineral dissolution on bulk geomechanical properties. Hence, although often disregarded, the understanding of particle-scale mechanisms responsible for alterations is necessary to predict the extent of geomechanical alteration as a function of dissolved mineral amounts. This study investigates the CO2-related rock chemo-mechanical alteration through numerical modeling and matching of naturally altered rocks probed with micro-scratch tests. We use a model that couples the discrete element method (DEM) and the bonded particle model (BPM) to perform simulations of micro-scratch tests on synthetic rocks that mimic Entrada sandstone. Experimental results serve to calibrate numerical scratch tests with DEM-BPM parameters. Sensitivity analyses indicate that the cement size and bond shear strength are the most sensitive microscopic parameters that govern the CO2-induced alteration in Entrada sandstone. Reductions in cement size lead to decrease in scratch toughness and an increase in ductility in the rock samples. This work demonstrates how small variations of microscopic bond properties in cemented sandstone can lead to significant changes in macroscopic large-strain mechanical properties.

  12. Derivation and application of mathematical model for well test analysis with variable skin factor in hydrocarbon reservoirs (United States)

    Liu, Pengcheng; Li, Wenhui; Xia, Jing; Jiao, Yuwei; Bie, Aifang


    Skin factor is often regarded as a constant in most of the mathematical model for well test analysis in oilfields, but this is only a kind of simplified treatment with the actual skin factor changeable. This paper defined the average permeability of a damaged area as a function of time by using the definition of skin factor. Therefore a relationship between a variable skin factor and time was established. The variable skin factor derived was introduced into existing traditional models rather than using a constant skin factor, then, this newly derived mathematical model for well test analysis considering variable skin factor was solved by Laplace transform. The dimensionless wellbore pressure and its derivative changed with dimensionless time were plotted with double logarithm and these plots can be used for type curve fitting. The effects of all the parameters in the expression of variable skin factor were analyzed based on the dimensionless wellbore pressure and its derivative. Finally, actual well testing data were used to fit the type curves developed which validates the applicability of the mathematical model from Sheng-2 Block, Shengli Oilfield, China.

  13. Feasibility study on application of volume acid fracturing technology to tight gas carbonate reservoir development

    Directory of Open Access Journals (Sweden)

    Nianyin Li


    Full Text Available How to effectively develop tight-gas carbonate reservoir and achieve high recovery is always a problem for the oil and gas industry. To solve this problem, domestic petroleum engineers use the combination of the successful experiences of North American shale gas pools development by stimulated reservoir volume (SRV fracturing with the research achievements of Chinese tight gas development by acid fracturing to propose volume acid fracturing technology for fractured tight-gas carbonate reservoir, which has achieved a good stimulation effect in the pilot tests. To determine what reservoir conditions are suitable to carry out volume acid fracturing, this paper firstly introduces volume acid fracturing technology by giving the stimulation mechanism and technical ideas, and initially analyzes the feasibility by the comparison of reservoir characteristics of shale gas with tight-gas carbonate. Then, this paper analyzes the validity and limitation of the volume acid fracturing technology via the analyses of control conditions for volume acid fracturing in reservoir fracturing performance, natural fracture, horizontal principal stress difference, orientation of in-situ stress and natural fracture, and gives the solution for the limitation. The study results show that the volume acid fracturing process can be used to greatly improve the flow environment of tight-gas carbonate reservoir and increase production; the incremental or stimulation response is closely related with reservoir fracturing performance, the degree of development of natural fracture, the small intersection angle between hydraulic fracture and natural fracture, the large horizontal principal stress difference is easy to form a narrow fracture zone, and it is disadvantageous to create fracture network, but the degradable fiber diversion technology may largely weaken the disadvantage. The practices indicate that the application of volume acid fracturing process to the tight-gas carbonate

  14. Current limitations and recommendations to improve testing for the environmental assessment of endocrine active substances (United States)

    Coady, Katherine K.; Biever, Ronald C.; Denslow, Nancy D.; Gross, Melanie; Guiney, Patrick D.; Holbech, Henrik; Karouna-Renier, Natalie K.; Katsiadaki, Ioanna; Krueger, Hank; Levine, Steven L.; Maack, Gerd; Williams, Mike; Wolf, Jeffrey C.; Ankley, Gerald T.


    In the present study, existing regulatory frameworks and test systems for assessing potential endocrine active chemicals are described, and associated challenges are discussed, along with proposed approaches to address these challenges. Regulatory frameworks vary somewhat across geographies, but all basically evaluate whether a chemical possesses endocrine activity and whether this activity can result in adverse outcomes either to humans or to the environment. Current test systems include in silico, in vitro, and in vivo techniques focused on detecting potential endocrine activity, and in vivo tests that collect apical data to detect possible adverse effects. These test systems are currently designed to robustly assess endocrine activity and/or adverse effects in the estrogen, androgen, and thyroid hormone signaling pathways; however, there are some limitations of current test systems for evaluating endocrine hazard and risk. These limitations include a lack of certainty regarding: 1) adequately sensitive species and life stages; 2) mechanistic endpoints that are diagnostic for endocrine pathways of concern; and 3) the linkage between mechanistic responses and apical, adverse outcomes. Furthermore, some existing test methods are resource intensive with regard to time, cost, and use of animals. However, based on recent experiences, there are opportunities to improve approaches to and guidance for existing test methods and to reduce uncertainty. For example, in vitro high-throughput screening could be used to prioritize chemicals for testing and provide insights as to the most appropriate assays for characterizing hazard and risk. Other recommendations include adding endpoints for elucidating connections between mechanistic effects and adverse outcomes, identifying potentially sensitive taxa for which test methods currently do not exist, and addressing key endocrine pathways of possible concern in addition to those associated with estrogen, androgen, and thyroid

  15. Flow characteristics of Hijiori HDR reservoir form circulation test in 1995; Koon tantai Hijiori jikkenjo ni okeru shinbu choryuso yobi junkan shiken (1995 nendo) kekka to ryudo kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Fukushima, N.; Hyodo, M.; Shinohara, N.; Takasugi, S. [Geothermal Energy Research and Development Co. Ltd., Tokyo (Japan)


    This paper reports the result of a preliminary circulation test conducted in fiscal 1995 on a deep reservoir (at a depth of about 2200 m) in the Hijiori hot dry rock experimental field. One water injection well and two production wells were drilled to constitute a circulation loop, to which the circulation test was performed to investigate the flow characteristics thereof. The result revealed the following matters: total amount of injected water of 51500 m{sup 3} resulted in a total fluid recovery rate of about 40%; as a result of well stimulation given twice during the initial stage of the water injection, the continuity impedance in the vicinity of the injection well decreased largely (however, the continuity improvement upon the second attempt was considerably inferior to that from the first attempt); and increase in the water injection amount does not necessarily lead to increase in the production amount. The paper describes additionally that it is extremely difficult to interpret non-linearity between the injection and production amounts by using a model prepared previously with a main objective to analyze the Hijiori HDR circulation system. 1 ref., 9 figs., 1 tab.

  16. 49 CFR 393.50 - Reservoirs required. (United States)


    ... depressing the brake pedal or treadle valve to the limit of its travel. (c) Safeguarding of air and vacuum... NECESSARY FOR SAFE OPERATION Brakes § 393.50 Reservoirs required. (a) Reservoir capacity for air-braked... driver to make a full service brake application with the engine stopped without depleting the air...

  17. Limited-information goodness-of-fit testing of hierarchical item factor models. (United States)

    Cai, Li; Hansen, Mark


    In applications of item response theory, assessment of model fit is a critical issue. Recently, limited-information goodness-of-fit testing has received increased attention in the psychometrics literature. In contrast to full-information test statistics such as Pearson's X(2) or the likelihood ratio G(2) , these limited-information tests utilize lower-order marginal tables rather than the full contingency table. A notable example is Maydeu-Olivares and colleagues'M2 family of statistics based on univariate and bivariate margins. When the contingency table is sparse, tests based on M2 retain better Type I error rate control than the full-information tests and can be more powerful. While in principle the M2 statistic can be extended to test hierarchical multidimensional item factor models (e.g., bifactor and testlet models), the computation is non-trivial. To obtain M2 , a researcher often has to obtain (many thousands of) marginal probabilities, derivatives, and weights. Each of these must be approximated with high-dimensional numerical integration. We propose a dimension reduction method that can take advantage of the hierarchical factor structure so that the integrals can be approximated far more efficiently. We also propose a new test statistic that can be substantially better calibrated and more powerful than the original M2 statistic when the test is long and the items are polytomous. We use simulations to demonstrate the performance of our new methods and illustrate their effectiveness with applications to real data. © 2012 The British Psychological Society.

  18. Current Limitations and Recommendations to Improve Testing for the Environmental Assessment of Endocrine Active Substances

    DEFF Research Database (Denmark)

    Coady, Katherine K; Biever, Ronald C; Denslow, Nancy D


    hazard and risk. These limitations include a lack of certainty regarding: 1) adequately sensitive species and life-stages, 2) mechanistic endpoints that are diagnostic for endocrine pathways of concern, and 3) the linkage between mechanistic responses and apical, adverse outcomes. Furthermore, some...... to prioritize chemicals for testing and provide insights as to the most appropriate assay(s) for characterizing hazard and risk. Other recommendations include adding endpoints for elucidating connections between mechanistic effects and adverse outcomes, identifying potentially sensitive taxa for which test...

  19. New materials for actively cooled limiters: results of laboratory and in-pile-TEXTOR tests

    International Nuclear Information System (INIS)

    Koizlik, K.; Hoven, H.; Gotoh, Y.; Linke, J.; Nickel, H.; Thiele, B.; Wallura, E.


    Materials for high heat flux components of the first wall in todays plasma facilities are heat resistant Ni- or Fe-base alloys or fine grain graphites with or without coatings. Next generation plasma machines with longer pulse lengths require improved materials for these components, primarily for actively cooled limiters. The following presentation contributes to the choice of those new materials and the investigations and tests of possible candidates. (author)

  20. Testing for Multiple Bubbles 2: Limit Theory of Real Time Detectors


    Peter C. B. Phillips; Shu-Ping Shi; Jun Yu


    This paper provides the limit theory of real time dating algorithms for bubble detection that were suggested in Phillips, Wu and Yu (2011, PWY) and Phillips, Shi and Yu (2013b, PSY). Bubbles are modeled using mildly explosive bubble episodes that are embedded within longer periods where the data evolves as a stochastic trend, thereby capturing normal market behavior as well as exuberance and collapse. Both the PWY and PSY estimates rely on recursive right tailed unit root tests (each with a d...

  1. Force Limited Vibration Testing and Subsequent Redesign of the Naval Postgraduate School CubeSat Launcher (United States)


    satellite is advantageous as some development, test and integration processes can be standardized, resulting in more cost effective and responsive...31 Figure 17. Z-Axis Force Limits at Qualification Levels for Integrated NPSCuL .............32 Figure 18. Tri-Axial Piezoelectric Force...Mises Stress Plot for + 5g , + 5g , -7g Loading Case ..................................78 Figure 57. X Axis Sine Sweep Comparisons between NPSCuL-v1 and

  2. The introduction of syphilis point of care tests in resource limited settings. (United States)

    Marks, Michael; Mabey, David Cw


    Syphilis remains an important and preventable cause of stillbirth and neonatal mortality. About 1 million women with active syphilis become pregnant each year. Without treatment, 25% of them will deliver a stillborn baby and 33% a low birth weight baby with an increased chance of dying in the first month of life. Adverse pregnancy outcomes due to syphilis can be prevented by screening pregnant women, and treating those who test positive with a single dose of penicillin before 28 weeks' gestation. Areas covered: This manuscript covers the impact of syphilis on pregnancy outcome, the diagnosis of syphilis, with a special focus on point of care (POC) tests, and challenges to the introduction of POC tests, and their potential impact on the control and prevention of syphilis in resource limited settings. Expert commentary: POC tests for syphilis are available which meet the ASSURED criteria, and could make syphilis screening accessible to all women anywhere in the world who attend an antenatal clinic. High quality dual POC tests for HIV and syphilis could ensure that well-funded programmes for the prevention of mother to child transmission of HIV can contribute towards increased coverage of antenatal syphilis screening, and prevent more than 300,000 adverse pregnancy outcomes due to syphilis annually. Alongside investment to increase availability of syphilis POC tests, operational research is needed to understand how best to improve screening of pregnant women and to translate test availability into improved pregnancy outcomes.

  3. Enhanced oil recovery in naturally fractured reservoirs in mexico, technical challenge

    Energy Technology Data Exchange (ETDEWEB)

    Garcia H, Francisco; Meza P, Edgar; Moran O, Oscar [PEMEX - Petroleos Mexicanos, Mexico D.F. (Mexico)


    Unlike single porosity reservoirs, naturally fractured reservoirs have several problems to implant any additional recovery processes (secondary or enhanced) due to a great amount of oil is trapped in the matrix and the injected fluids bypass matrix through fractures because of they have a greater capacity to allow flow. So far there, there is not a complete knowledge of improved recovery processes that can be applied to naturally fractured reservoirs, there are some laboratory tests, tests pilot in fields and very few projects in execution. All this make an opportunity area to develop more investigation. Taking into account the previous limitations is possible to begin to evaluate several processes for naturally fractured reservoirs as: gas injection, chemical treatments and thermal processes, but a common process to all of them is gravity drainage which implies new considerations in operation to extract hydrocarbons of the fractured reservoirs. There are many challenges to implant additional recovery processes in naturally fractured reservoirs and we mentioned in this work, moreover we show Mexican experience in EOR processes in Naturally Fractured Reservoirs, too. (author)

  4. Detection limits of the strip test and PCR for genetically modified corn in Brazil. (United States)

    Nascimento, V E; Von Pinho, É V R; Von Pinho, R G; do Nascimento, A D


    Brazilian legislation establishes a labeling limit for products that contain more than 1% material from genetically modified organisms (GMOs). We assessed the sensitivity of the lateral flow strip test in detection of the GMO corn varieties Bt11 and MON810 and the specificity and sensitivity of PCR techniques for their detection. For the strip test, the GMO seeds were mixed with conventional seeds at levels of 0.2, 0.4 and 0.8% for Bt11, and 0.4, 0.8 and 1.6% for MON810. Three different methodologies were assessed and whole seeds, their endosperm and embryonic axis were used. For the PCR technique, the GMO seeds of each of the two varieties were mixed with conventional seeds at levels of 20, 10, 5, 2, 1, and 0.5%. The seeds were ground and the DNA extracted. For detection of the GMO material, specific primers were used for MON810 and Bt11 and maize zein as an endogenous control. The sensitivity of the strip test varied for both maize varieties and methodologies. The test was positive for Bt11 only at 0.8%, in contrast with the detection limit of 0.4% indicated by the manufacturer. In the multiplex PCR, the primers proved to be specific for the different varieties. These varieties were detected in samples with one GMO seed in 100. Thus, this technique proved to be efficient in detecting contaminations equal to or greater than 1%.

  5. High heat flux tests on TiC coated molybdenum and graphite limiters for tokamak experiments

    International Nuclear Information System (INIS)

    Nakamura, Hiroo; Niikura, Setsuo; Uchikawa, Takashi; Onozuka, Masanori; Yamao, Hiroyuki; Nayama, Michisuke; Ioki, Kimihiro.


    High heat flux tests have been performed using a 120 kW electron beam test facility to study thermal shock and thermal cycle resistances of TiC coated molybdenum, three kinds of high grade graphite (IG-11, AXF-5Q, ATJ) and pyrolytic graphite (PYROID) as tokamak limiter materials. Three types of samples were used; JT-60 fixed limiter type (TiC/Mo), plate type (IG-11, AXF-5Q, ATJ, PYROID) and bumper limiter type (IG-11). Test conditions are 0.9 ∼ 2.2 kW/cm 2 x 2.5 ∼ 21 sec in the thermal shock tests, and 340 W/cm 2 x 3 sec x 1000 cycles in the thermal cycle tests, respectively. In the case of TiC/Mo, no damage was observed in the condition of 1.1 kW/cm 2 x 11 sec. In the conditions of 1.1 kW/cm 2 x 21 sec and 2.2 kW/cm 2 x 2.5 sec, surface melting and cracking of TiC coating were observed. In the thermal cycle test of TiC/Mo, there was no damage. In the case of plate type graphites (IG-11, AXF-5Q, ATJ), there was no damage in the condition of 1.1 kW/cm 2 x 11 sec. On the other hand, surface erosions were observed in the conditions of 1.1 kW/cm 2 x 21 sec and 2.2 kW/cm 2 x 4.0 sec. However, there was no cracking. In the case of PYROID, there was no surface erosion in the condition of 1.1 kW/cm 2 x 31 sec. In the case of bumper limiter type graphite, cracking was observed in the conditions of 0.9 kW/cm 2 x 10 sec. Observation and surface analyses by SEM, AES and EPMA have been performed. Also, thermal and structural analyses have been performed. (author)

  6. Electromagnetic Heating Methods for Heavy Oil Reservoirs

    International Nuclear Information System (INIS)

    Sahni, A.; Kumar, M.; Knapp, R.B.


    The most widely used method of thermal oil recovery is by injecting steam into the reservoir. A well-designed steam injection project is very efficient in recovering oil, however its applicability is limited in many situations. Simulation studies and field experience has shown that for low injectivity reservoirs, small thickness of the oil-bearing zone, and reservoir heterogeneity limits the performance of steam injection. This paper discusses alternative methods of transferring heat to heavy oil reservoirs, based on electromagnetic energy. They present a detailed analysis of low frequency electric resistive (ohmic) heating and higher frequency electromagnetic heating (radio and microwave frequency). They show the applicability of electromagnetic heating in two example reservoirs. The first reservoir model has thin sand zones separated by impermeable shale layers, and very viscous oil. They model preheating the reservoir with low frequency current using two horizontal electrodes, before injecting steam. The second reservoir model has very low permeability and moderately viscous oil. In this case they use a high frequency microwave antenna located near the producing well as the heat source. Simulation results presented in this paper show that in some cases, electromagnetic heating may be a good alternative to steam injection or maybe used in combination with steam to improve heavy oil production. They identify the parameters which are critical in electromagnetic heating. They also discuss past field applications of electromagnetic heating including technical challenges and limitations

  7. Limited impact of awareness-raising campaigns on hepatitis C testing practices among general practitioners. (United States)

    McLeod, A; Cullen, B L; Hutchinson, S J; Roy, K M; Dillon, J F; Stewart, E A; Goldberg, D J


    The global hepatitis strategy calls for increased effort to diagnose those infected, with a target of 90% diagnosed by 2030. Scotland's Action Plan on Hepatitis C included awareness-raising campaigns, undertaken during 2008-2011, to promote testing by general practitioners. We examined hepatitis C virus (HCV) testing practice among general practitioners before and following these campaigns. Scottish general practitioners were surveyed, using Dillman's method, in 2007 and 2013; response rates were 69% and 60%, respectively. Most respondents offer testing when presented with a risk history (86% in 2007, 88% in 2013) but only one-fifth actively sought out risk factors (19% in 2007, 21% in 2013). Testing was reportedly always/almost always/usually offered to people who inject drugs (84% in 2007, 87% in 2013). Significant improvements in the offer of testing were reported in patients with abnormal LFTs (41% in 2007, 65% in 2013, Ptest to patients who had received medical/dental treatment in high prevalence countries (P=.001). Our findings suggest that government-led awareness raising campaigns have limited impact on general practitioners' testing practices. If the majority of the HCV-infected population are to be diagnosed, practitioner-based or physician-centred interventions should be considered alongside educational initiatives targeted at professionals. © 2017 John Wiley & Sons Ltd.

  8. Improving reservoir history matching of EM heated heavy oil reservoirs via cross-well seismic tomography

    KAUST Repository

    Katterbauer, Klemens


    Enhanced recovery methods have become significant in the industry\\'s drive to increase recovery rates from oil and gas reservoirs. For heavy oil reservoirs, the immobility of the oil at reservoir temperatures, caused by its high viscosity, limits the recovery rates and strains the economic viability of these fields. While thermal recovery methods, such as steam injection or THAI, have extensively been applied in the field, their success has so far been limited due to prohibitive heat losses and the difficulty in controlling the combustion process. Electromagnetic (EM) heating via high-frequency EM radiation has attracted attention due to its wide applicability in different environments, its efficiency, and the improved controllability of the heating process. While becoming a promising technology for heavy oil recovery, its effect on overall reservoir production and fluid displacements are poorly understood. Reservoir history matching has become a vital tool for the oil & gas industry to increase recovery rates. Limited research has been undertaken so far to capture the nonlinear reservoir dynamics and significantly varying flow rates for thermally heated heavy oil reservoir that may notably change production rates and render conventional history matching frameworks more challenging. We present a new history matching framework for EM heated heavy oil reservoirs incorporating cross-well seismic imaging. Interfacing an EM heating solver to a reservoir simulator via Andrade’s equation, we couple the system to an ensemble Kalman filter based history matching framework incorporating a cross-well seismic survey module. With increasing power levels and heating applied to the heavy oil reservoirs, reservoir dynamics change considerably and may lead to widely differing production forecasts and increased uncertainty. We have shown that the incorporation of seismic observations into the EnKF framework can significantly enhance reservoir simulations, decrease forecasting

  9. Hydrogen isotope exchange and conditioning in graphite limiters used in the Tokamak Fusion Test Reactor

    International Nuclear Information System (INIS)

    LaMarche, P.H.; Dylla, H.F.; McCarthy, P.J.; Ulrickson, M.


    Isotopic exchange experiments performed in the Tokamak Fusion Test Reactor (TFTR) are used to examine the outgassing and diffusive properties of graphite used as the plasma limiter. Changeover from hydrogen to deuterium for different periods ranges from approx.600 to 60 plasma discharges, which appears to be correlated in the limiter temperature. We present a simple analytical model that predicts a fast transient (approx.10 plasma discharges) changeover, where the deuterium fueling dilutes the adsorbed and near surface hydrogen, and a slowly changing term where bulk hydrogen diffuses to the surface. Using this model we can extract an activation energy for diffusion of 0.15 +- 0.02 eV. We hypothesize that interpore diffusion for this porous (approx.15%) material is consistent with our observations

  10. Skid resistance and surface roughness testing of historic stone surfaces: advantages and limitations (United States)

    Török, Ákos


    Skid resistance tests are mostly applied for testing road surfaces and almost never applied for testing stones at cultural heritage sites. The present study focuses on the possibilities of using these techniques in assessing the surface roughness of paving stones at a historic site. Two different methods were used in a comparative way to evaluate the surface properties of various types of stones ranging from travertine to non-porous limestone and granite. The applied techniques included the use of SRT pendulum (Skid Resistance Tester) providing USRV values and a mobile equipment to analyze the surface properties (Floor Slide Control) by surface profiling and providing angle of friction. The main aims of tests were to understand the wearing of stone materials due to intense pedestrian use and to detect surface changes/surface roughness and slip resistance within few year periods. The measured loss in surface slip resistance (i.e. USRV values) was in the order of 20% for granites, while most limestones lost at least 40% in terms of USRV values. An opposite trend was detected for a porous travertine type, where the surface became rougher after years of use. The limitations of these techniques are also addressed in the paper. The tests have shown that the introduction of the use of these equipments in heritage studies provide useful information on the longevity of historic stone pavements that are open for public use.

  11. Reservoir fisheries of Asia

    International Nuclear Information System (INIS)

    Silva, S.S. De.


    At a workshop on reservoir fisheries research, papers were presented on the limnology of reservoirs, the changes that follow impoundment, fisheries management and modelling, and fish culture techniques. Separate abstracts have been prepared for three papers from this workshop

  12. Large reservoirs: Chapter 17 (United States)

    Miranda, Leandro E.; Bettoli, Phillip William


    Large impoundments, defined as those with surface area of 200 ha or greater, are relatively new aquatic ecosystems in the global landscape. They represent important economic and environmental resources that provide benefits such as flood control, hydropower generation, navigation, water supply, commercial and recreational fisheries, and various other recreational and esthetic values. Construction of large impoundments was initially driven by economic needs, and ecological consequences received little consideration. However, in recent decades environmental issues have come to the forefront. In the closing decades of the 20th century societal values began to shift, especially in the developed world. Society is no longer willing to accept environmental damage as an inevitable consequence of human development, and it is now recognized that continued environmental degradation is unsustainable. Consequently, construction of large reservoirs has virtually stopped in North America. Nevertheless, in other parts of the world construction of large reservoirs continues. The emergence of systematic reservoir management in the early 20th century was guided by concepts developed for natural lakes (Miranda 1996). However, we now recognize that reservoirs are different and that reservoirs are not independent aquatic systems inasmuch as they are connected to upstream rivers and streams, the downstream river, other reservoirs in the basin, and the watershed. Reservoir systems exhibit longitudinal patterns both within and among reservoirs. Reservoirs are typically arranged sequentially as elements of an interacting network, filter water collected throughout their watersheds, and form a mosaic of predictable patterns. Traditional approaches to fisheries management such as stocking, regulating harvest, and in-lake habitat management do not always produce desired effects in reservoirs. As a result, managers may expend resources with little benefit to either fish or fishing. Some locally

  13. An index of reservoir habitat impairment (United States)

    Miranda, L.E.; Hunt, K.M.


    Fish habitat impairment resulting from natural and anthropogenic watershed and in-lake processes has in many cases reduced the ability of reservoirs to sustain native fish assemblages and fisheries quality. Rehabilitation of impaired reservoirs is hindered by the lack of a method suitable for scoring impairment status. To address this limitation, an index of reservoir habitat impairment (IRHI) was developed by merging 14 metrics descriptive of common impairment sources, with each metric scored from 0 (no impairment) to 5 (high impairment) by fisheries scientists with local knowledge. With a plausible range of 5 to 25, distribution of the IRHI scores ranged from 5 to 23 over 482 randomly selected reservoirs dispersed throughout the USA. The IRHI reflected five impairment factors including siltation, structural habitat, eutrophication, water regime, and aquatic plants. The factors were weakly related to key reservoir characteristics including reservoir area, depth, age, and usetype, suggesting that common reservoir descriptors are poor predictors of fish habitat impairment. The IRHI is rapid and inexpensive to calculate, provides an easily understood measure of the overall habitat impairment, allows comparison of reservoirs and therefore prioritization of restoration activities, and may be used to track restoration progress. The major limitation of the IRHI is its reliance on unstandardized professional judgment rather than standardized empirical measurements. ?? 2010 US Government.

  14. Clinical evaluation and stress test have limited value in the diagnosis of in-stent restenosis. (United States)

    Andersen, Karl; Steinthórsdóttir, Sandra Dís; Haraldsdottir, Sigurdis; Gudnason, Thorarinn


    In-stent restenosis (ISR) is the main limitation of percutaneous coronary interventions (PCI), occurring in approximately 25% of cases. Although frequently asymptomatic, many PCI patients present with recurrent symptoms of chest pain at follow-up raising a clinical suspicion of ISR. The diagnosis of ISR can be challenging in these patients and difficult to rule out without repeat coronary angiography. We prospectively investigated the diagnostic accuracy of clinical evaluation and exercise stress testing to detect ISR as compared to coronary angiography, in a consecutive, unselected cohort of PCI patients. We studied 91 patients with a total of 143 stents. Clinical evaluation predicted ISR to be likely in 19% of cases and the exercise test was positive in 29%. The binary restenosis rate was 21%. Clinical evaluation had a positive predictive value of 29% and accuracy of 71%, while exercise stress testing had a positive predictive value of 19% and accuracy of 65%. In conclusion, we found the diagnostic accuracy of clinical evaluation to be low and not significantly improved by exercise stress testing when evaluating PCI patients for ISR.

  15. Experimental investigation of thermal limits in parallel plate configuration for the future material testing reactor (JHR)

    International Nuclear Information System (INIS)

    Brigitte Noel


    Full text of publication follows: The design of the future material testing reactor, named Jules Horowitz Reactor and dedicated to technological irradiations, will allow very high performances. The JHR will be cooled and moderated by light water. The preliminary core of JHR consists of 46 assemblies, arranged in a triangular lattice inside a rectangular aluminium matrix. It is boarded on two sides by a beryllium reflector. The other two sides are left free in order to introduce mobile irradiation devices. The JHR assembly would be composed of 3 x 6 cylindrical fuel plates maintained by 3 stiffeners. The external diameter of the assembly is close to 8 cm with a 600 mm heated length, coolant channels having a 1.8 mm gap width. The JHR core must be designed to accommodate high power densities using a high coolant mass flux and sub-cooling level at moderate pressure. The JHR core configuration with multi-channels is subject to a potential excursive instability, called flow redistribution, and is distinguished from a true critical heat flux which would occur at a fixed channel flow rate. At thermal-hydraulic conditions applicable to the JHR, the availability of experimental data for both flow redistribution and CHF is very limited. Consequently, a thermal-hydraulic test facility (SULTAN-RJH) was designed and built in CEA-Grenoble to simulate a full-length coolant sub-channel representative of the JHR core, allowing determination of both thermal limits under relevant thermal hydraulics conditions. The SULTAN-RJH test section simulates a single sub-channel in the JHR core with a cross section corresponding to a mean span (∼50 mm) that has a full reactor length (600 mm), the same flow channel gap (1.5 mm) and Inconel plates of 1 mm thickness. The tests with light water flowing vertically upward will investigate a heat flux range of 0-7 MW/m 2 , velocity range of 0.6-18 m/s, exit pressure range of 0.2-1.0 MPa and inlet temperature range of 25-180 deg. C. The test section

  16. Stream, Lake, and Reservoir Management. (United States)

    Dai, Jingjing; Mei, Ying; Chang, Chein-Chi


    This review on stream, lake, and reservoir management covers selected 2016 publications on the focus of the following sections: Stream, lake, and reservoir management • Water quality of stream, lake, and reservoirReservoir operations • Models of stream, lake, and reservoir • Remediation and restoration of stream, lake, and reservoir • Biota of stream, lake, and reservoir • Climate effect of stream, lake, and reservoir.

  17. Status of Wheeler Reservoir

    Energy Technology Data Exchange (ETDEWEB)


    This is one in a series of status reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Wheeler Reservoir summarizes reservoir purposes and operation, reservoir and watershed characteristics, reservoir uses and use impairments, and water quality and aquatic biological conditions. The information presented here is from the most recent reports, publications, and original data available. If no recent data were available, historical data were summarized. If data were completely lacking, environmental professionals with special knowledge of the resource were interviewed. 12 refs., 2 figs.

  18. Development of gas and gas condensate reservoirs

    Energy Technology Data Exchange (ETDEWEB)



    In the study of gas reservoir development, the first year topics are restricted on reservoir characterization. There are two types of reservoir characterization. One is the reservoir formation characterization and the other is the reservoir fluid characterization. For the reservoir formation characterization, calculation of conditional simulation was compared with that of unconditional simulation. The results of conditional simulation has higher confidence level than the unconditional simulation because conditional simulation considers the sample location as well as distance correlation. In the reservoir fluid characterization, phase behavior calculations revealed that the component grouping is more important than the increase of number of components. From the liquid volume fraction with pressure drop, the phase behavior of reservoir fluid can be estimated. The calculation results of fluid recombination, constant composition expansion, and constant volume depletion are matched very well with the experimental data. In swelling test of the reservoir fluid with lean gas, the accuracy of dew point pressure forecast depends on the component characterization. (author). 28 figs., 10 tabs.

  19. Optimal reservoir operation policies using novel nested algorithms (United States)

    Delipetrev, Blagoj; Jonoski, Andreja; Solomatine, Dimitri


    optimization algorithm into the state transition that lowers the starting problem dimension and alleviates the curse of dimensionality. The algorithms can solve multi-objective optimization problems, without significantly increasing the complexity and the computational expenses. The algorithms can handle dense and irregular variable discretization, and are coded in Java as prototype applications. The three algorithms were tested at the multipurpose reservoir Knezevo of the Zletovica hydro-system located in the Republic of Macedonia, with eight objectives, including urban water supply, agriculture, ensuring ecological flow, and generation of hydropower. Because the Zletovica hydro-system is relatively complex, the novel algorithms were pushed to their limits, demonstrating their capabilities and limitations. The nSDP and nRL derived/learned the optimal reservoir policy using 45 (1951-1995) years historical data. The nSDP and nRL optimal reservoir policy was tested on 10 (1995-2005) years historical data, and compared with nDP optimal reservoir operation in the same period. The nested algorithms and optimal reservoir operation results are analysed and explained.

  20. Task 2 - Limits for High-Frequency Conducted Susceptibility Testing - CS114 (NRC-HQ-60-14-D-0015)

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Richard Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ewing, Paul D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Moses, Rebecca J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)


    A principal focus of Task 2 under this project was for ORNL to evaluate the basis for susceptibility testing against high-frequency conducted interference and to establish recommendations to resolve concerns about the severity of test limits for the conducted susceptibility (CS) test, CS114, from MIL-STD-461. The primary concern about the test limit has been characterized by the EPRI EMI Working Group in the following terms: Demonstrating compliance with the CS114 test limits recommended in TR-102323 has proven to be problematic, even for components that have been tested to commercial standards and demonstrated proper operation in industrial applications [6]. Specifically, EPRI notes that the CS114 limits approved in regulatory documents are significantly higher than those invoked by the US military and similar commercial standards in the frequency range below 200 kHz. For this task, ORNL evaluated the original approach to establishing the test limit, EPRI technical findings from a review of the limit, and the regulatory basis through which the currently approved limits were accepted. Based on this analysis, strategies have been developed regarding changes to the CS114 limit that can resolve the technical concerns raised by the industry. Guided by the principles that reasonable assurance of safety must not be compromised but excessive conservatism should be reduced, recommendations on a suitable basis for a revised limit have been developed and can be incorporated into the planned Revision 2 of RG 1.180.

  1. Limitations of the inspection and testing concepts for pressurised components from the viewpoint of operating experience

    International Nuclear Information System (INIS)

    Schulz, H.


    The role of in-service inspection and testing is to contribute to a safe and reliable operation of systems, structures and components. It is therefore the objective of inspections and tests to identify malfunctions and degradations at a stage early enough to avoid detrimental impacts on safety as well as on the reliability of the plant. Taking mostly the pressure boundary of German light-water reactors as an example, it is the intention of this paper to analyse how successful present inspection and testing requirements are and to discuss limitations. Based on a review of the world-wide operating experience the following questions of a more generic nature are addressed: - Are the relevant damage mechanisms being addressed in our codes and standards? - What are the criteria to develop a representative scope of inspection? - How to maintain a sufficient level of information for a decreasing number of nuclear power plants in operation? It can be concluded that the revision of codes and standards according to lessons learned from operating experience remains as an ongoing process. Furthermore, the criteria applied to derive a representative scope of inspection need to be addressed in more detail, specifically with respect to corrosion. The continuous evaluation of operating experience of a large number of plants is the most valuable source to identify beginning degradations. (author)

  2. Shaker Random Testing with Low Kurtosis: Review of the Methods and Application for Sigma Limiting

    Directory of Open Access Journals (Sweden)

    Alexander Steinwolf


    Full Text Available The non-Gaussian random shaker testing with kurtosis control has been known as a way of increasing the excitation crest factor in order to realistically simulate ground vehicle vibrations and other situations when the time history includes extreme peaks higher than those appearing in Gaussian random signals. However, an opposite action is also useful in other applications, particularly in modal testing. If the PSD is the only test specification, more power can be extracted from the same shaker if the crest factor is decreased and an extra space is created between the peaks of reduced height and the system abort limit. To achieve this, a technique of sigma clipping is commonly used but it generates harmonic distortions reducing dynamic range of shaker system. It is shown in the paper that the non-Gaussian phase selection in the IFFT generation can reduce kurtosis to 1.7 and bring the crest factor of drive signals from 4.5 to 2. The phase selection method does this without any loss of the controller's dynamic range that inevitably occurs after sigma clipping or polynomial transformation of time histories.

  3. Design, Test and Demonstration of Saturable Reactor High-Temperature Superconductor Fault Current Limiters

    Energy Technology Data Exchange (ETDEWEB)

    Darmann, Frank [Zenergy Power, Inc., Burlingame, CA (United States); Lombaerde, Robert [Zenergy Power, Inc., Burlingame, CA (United States); Moriconi, Franco [Zenergy Power, Inc., Burlingame, CA (United States); Nelson, Albert [Zenergy Power, Inc., Burlingame, CA (United States)


    Zenergy Power has successfully designed, built, tested, and installed in the US electrical grid a saturable reactor Fault Current Limiter. Beginning in 2007, first as SC Power Systems and from 2008 as Zenergy Power, Inc., ZP used DOE matching grant and ARRA funds to help refine the design of the saturated reactor fault current limiter. ZP ultimately perfected the design of the saturated reactor FCL to the point that ZP could reliably design a suitable FCL for most utility applications. Beginning with a very basic FCL design using 1G HTS for a coil housed in a LN2 cryostat for the DC bias magnet, the technology progressed to a commercial system that was offered for sale internationally. Substantial progress was made in two areas. First, the cryogenics cooling system progressed from a sub-cooled liquid nitrogen container housing the HTS coils to cryostats utilizing dry conduction cooling and reaching temperatures down to less than 20 degrees K. Large, round cryostats with warm bore diameters of 1.7 meters enabled the design of large tanks to hold the AC components. Second, the design of the AC part of the FCL was refined from a six legged spider design to a more compact and lighter design with better fault current limiting capability. Further refinement of the flux path and core shape led to an efficient saturated reactor design requiring less Ampere-turns to saturate the core. In conclusion, the development of the saturable reactor FCL led to a more efficient design not requiring HTS magnets and their associated peripheral equipment, which yielded a more economical product in line with the electric utility industry expectations. The original goal for the DOE funding of the ZP project Design, Test and Demonstration of Saturable Reactor High-Temperature Superconductor Fault Current Limiters was to stimulate the HTS wire industry with, first 1G, then 2G, HTS wire applications. Over the approximately 5 years of ZP's product development program, the amount of HTS

  4. A comparison of straight- and curved-path walking tests among mobility-limited older adults. (United States)

    Odonkor, Charles A; Thomas, Julia C; Holt, Nicole; Latham, Nancy; Vanswearingen, Jessie; Brach, Jennifer Sokol; Leveille, Suzanne G; Jette, Alan; Bean, Jonathan


    Habitual gait speed (HGS) and the figure-of-8 walking test (F8WT) are measures of walking ability that have been associated with mobility outcomes and disability among older adults. Our objective was to contrast the physiologic, health, and behavioral attributes underlying performance of these two walking tests among older adults with mobility limitations. HGS and F8WT were the primary outcomes. HGS was measured as time needed to walk a 4-m straight course at usual pace from standstill position. F8WT was measured as time to walk in a figure-of-8 pattern at self-selected usual pace from standstill position. Separate multivariable linear regression models were constructed that predicted walking performance. Independent variables included physiologic, cognitive-behavioral health attributes, and demographic information. Of 430 participants, 414 completed both walking tests. Participants were 67.7% female, had a mean age of 76.5 ± 7.0 years and a mean of 4.1 ± 2.0 chronic conditions. Mean HGS was 0.94 ± 0.23 m/s and mean F8WT was 8.80 ± 2.90 seconds. Within separate multivariable linear regression models (HGS: R (2) = .46, p model sensory loss. Cognitive and physiologic attributes uniquely associated with F8WT were cognitive processing speed and self-efficacy, and reaction time and heel-to-floor time. Pain and peak leg press strength were associated with only HGS. Both HGS and F8WT are useful tests of walking performance. Factors uniquely associated with F8WT suggest that it may be well suited for use among older adult patients with balance problems or at risk for falls.

  5. Development and Testing of a Transmission Voltage SuperLimiter™ Fault Current Limiter

    Energy Technology Data Exchange (ETDEWEB)

    Romanosky, Walter [American Superconductor Corporation, Devens, MA (United States)


    This report summarizes work by American Superconductor (AMSC), Los Alamos National Laboratory (LANL), Nexans, Siemens and Southern California Edison on a 138kV resistive type high temperature superconductor (HTS) fault current limiter (FCL) under a cooperative agreement with the U.S. Department of Energy (DOE). Phase 1A encompassed core technology development and system design and was previously reported (see summary that follows in Section 1.1 of the Introduction). This report primarily discusses work performed during Phase 1B, and addresses the fabrication and test of a single-phase prototype FCL. The results are presented along with a discussion of requirements/specifications and lessons learned to aid future development and product commercialization.

  6. A chemical EOR benchmark study of different reservoir simulators (United States)

    Goudarzi, Ali; Delshad, Mojdeh; Sepehrnoori, Kamy


    Interest in chemical EOR processes has intensified in recent years due to the advancements in chemical formulations and injection techniques. Injecting Polymer (P), surfactant/polymer (SP), and alkaline/surfactant/polymer (ASP) are techniques for improving sweep and displacement efficiencies with the aim of improving oil production in both secondary and tertiary floods. There has been great interest in chemical flooding recently for different challenging situations. These include high temperature reservoirs, formations with extreme salinity and hardness, naturally fractured carbonates, and sandstone reservoirs with heavy and viscous crude oils. More oil reservoirs are reaching maturity where secondary polymer floods and tertiary surfactant methods have become increasingly important. This significance has added to the industry's interest in using reservoir simulators as tools for reservoir evaluation and management to minimize costs and increase the process efficiency. Reservoir simulators with special features are needed to represent coupled chemical and physical processes present in chemical EOR processes. The simulators need to be first validated against well controlled lab and pilot scale experiments to reliably predict the full field implementations. The available data from laboratory scale include 1) phase behavior and rheological data; and 2) results of secondary and tertiary coreflood experiments for P, SP, and ASP floods under reservoir conditions, i.e. chemical retentions, pressure drop, and oil recovery. Data collected from corefloods are used as benchmark tests comparing numerical reservoir simulators with chemical EOR modeling capabilities such as STARS of CMG, ECLIPSE-100 of Schlumberger, REVEAL of Petroleum Experts. The research UTCHEM simulator from The University of Texas at Austin is also included since it has been the benchmark for chemical flooding simulation for over 25 years. The results of this benchmark comparison will be utilized to improve

  7. Economics of Developing Hot Stratigraphic Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Greg Mines; Hillary Hanson; Rick Allis; Joseph Moore


    Stratigraphic geothermal reservoirs at 3 – 4 km depth in high heat-flow basins are capable of sustaining 100 MW-scale power plants at about 10 c/kWh. This paper examines the impacts on the levelized cost of electricity (LCOE) of reservoir depth and temperature, reservoir productivity, and drillhole/casing options. For a reservoir at 3 km depth with a moderate productivity index by hydrothermal reservoir standards (about 50 L/s/MPa, 5.6 gpm/psi), an LCOE of 10c/kWh requires the reservoir to be at about 200°C. This is the upper temperature limit for pumps. The calculations assume standard hydrothermal drilling costs, with the production interval completed with a 7 inch liner in an 8.5 inch hole. If a reservoir at 4 km depth has excellent permeability characteristics with a productivity index of 100 L/s/MPa (11.3 gpm/psi), then the LCOE is about 11 c/kWh assuming the temperature decline rate with development is not excessive (< 1%/y, with first thermal breakthrough delayed by about 10 years). Completing wells with modest horizontal legs (e.g. several hundred meters) may be important for improving well productivity because of the naturally high, sub-horizontal permeability in this type of reservoir. Reducing the injector/producer well ratio may also be cost-effective if the injectors are drilled as larger holes.

  8. Application of artificial intelligence to reservoir characterization: An interdisciplinary approach. [Quarterly progress report], January 1--March 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, B.G.; Gamble, R.F.; Kerr, D.R.; Thompson, L.G.; Shenoi, S.


    The basis of this research is to apply novel techniques from Artificial Intelligence and Expert Systems in capturing, integrating and articulating key knowledge from geology, geostatistics, and petroleum engineering to develop accurate descriptions of petroleum reservoirs. The ultimate goal is to design and implement a single powerful expert system for use by small producers and independents to efficiently exploit reservoirs. The overall project plan to design the system to create integrated reservoir descriptions begins by initially developing an Al-based methodology for producing large-scale reservoir descriptions generated interactively from geology and well test data. Parallel to this task is a second task that develops an Al-based methodology that uses facies-biased information to generate small-scale descriptions of reservoir properties such as permeability and porosity. The third task involves consolidation and integration of the large-scale and small-scale methodologies to produce reservoir descriptions honoring all the available data. The final task will be technology transfer. With this plan, we have carefully allocated and sequenced the activities involved in each of the tasks to promote concurrent progress towards the research objectives. Moreover, the project duties are divided among the faculty member participants. Graduate students will work in teams with faculty members. The results of the integration are not merely limited to obtaining better characterizations of individual reservoirs. They have the potential to significantly impact and advance the discipline of reservoir characterization itself.


    Energy Technology Data Exchange (ETDEWEB)

    Abbas Firoozabadi


    The four chapters that are described in this report cover a variety of subjects that not only give insight into the understanding of multiphase flow in fractured porous media, but they provide also major contribution towards the understanding of flow processes with in-situ phase formation. In the following, a summary of all the chapters will be provided. Chapter I addresses issues related to water injection in water-wet fractured porous media. There are two parts in this chapter. Part I covers extensive set of measurements for water injection in water-wet fractured porous media. Both single matrix block and multiple matrix blocks tests are covered. There are two major findings from these experiments: (1) co-current imbibition can be more efficient than counter-current imbibition due to lower residual oil saturation and higher oil mobility, and (2) tight fractured porous media can be more efficient than a permeable porous media when subjected to water injection. These findings are directly related to the type of tests one can perform in the laboratory and to decide on the fate of water injection in fractured reservoirs. Part II of Chapter I presents modeling of water injection in water-wet fractured media by modifying the Buckley-Leverett Theory. A major element of the new model is the multiplication of the transfer flux by the fractured saturation with a power of 1/2. This simple model can account for both co-current and counter-current imbibition and computationally it is very efficient. It can be orders of magnitude faster than a conventional dual-porosity model. Part II also presents the results of water injection tests in very tight rocks of some 0.01 md permeability. Oil recovery from water imbibition tests from such at tight rock can be as high as 25 percent. Chapter II discusses solution gas-drive for cold production from heavy-oil reservoirs. The impetus for this work is the study of new gas phase formation from in-situ process which can be significantly

  10. Reservoir engineering and hydrogeology

    International Nuclear Information System (INIS)



    Summaries are included which show advances in the following areas: fractured porous media, flow in single fractures or networks of fractures, hydrothermal flow, hydromechanical effects, hydrochemical processes, unsaturated-saturated systems, and multiphase multicomponent flows. The main thrust of these efforts is to understand the movement of mass and energy through rocks. This has involved treating fracture rock masses in which the flow phenomena within both the fractures and the matrix must be investigated. Studies also address the complex coupling between aspects of thermal, hydraulic, and mechanical processes associated with a nuclear waste repository in a fractured rock medium. In all these projects, both numerical modeling and simulation, as well as field studies, were employed. In the theoretical area, a basic understanding of multiphase flow, nonisothermal unsaturated behavior, and new numerical methods have been developed. The field work has involved reservoir testing, data analysis, and case histories at a number of geothermal projects

  11. Spin-multipole effects in binary black holes and the test-body limit (United States)

    Vines, Justin; Steinhoff, Jan


    We discuss the effects of the black holes' spin-multipole structure in the orbital dynamics of binary black holes according to general relativity, focusing on the leading-post-Newtonian-order couplings at each order in an expansion in the black holes' spins. We first review previous widely confirmed results up through fourth order in spin, observe suggestive patterns therein, and discuss how the results can be extrapolated to all orders in spin with minimal information from the test-body limit. We then justify this extrapolation by providing a complete derivation within the post-Newtonian framework of a canonical Hamiltonian for a binary black hole, for generic orbits and spin orientations, which encompasses the leading post-Newtonian orders at all orders in spin. At the considered orders, the results reveal a precise equivalence between arbitrary-mass-ratio two-spinning-black-hole dynamics and the motion of a test black hole in a Kerr spacetime, as well as an intriguing relationship to geodesic motion in a Kerr spacetime.

  12. Full-scale crash-test evaluation of two load-limiting subfloors for general aviation airframes (United States)

    Carden, H. D.


    Three six place, low wing, twin engine general aviation airplane test specimens were crash tested at the Langley Impact Dynamics Research Facility under controlled free flight conditions. One structurally unmodified airplane was the base line specimen for the test series. The other two airplanes were structurally modified to incorporate load limiting (energy absorbing) subfloor concepts into the structure for full scale crash test evaluation and for comparison with the unmodified airplane test results. Typically, the lowest floor accelerations, the lowest anthropomorphic dummy responses, and the least seat crushing of standard and load limiting seats occurred in the airplanes modified with load limiting subfloors, wherein the greatest structural crushing of the subfloor took place. The better performing of the two load limiting subfloor concepts reduced the peak airplane floor accelerations to -25g to -30g as compared with approximately -40g to -55g for the unmodified airplane structure.

  13. Performance of two load-limiting subfloor concepts in full-scale general aviation airplane crash tests (United States)

    Carden, H. D.


    Three six-place, low wing, twin-engine general aviation airplane test specimens were crash tested at the langley Impact Dynamics research Facility under controlled free-flight conditions. One structurally unmodified airplane was the baseline airplane specimen for the test series. The other airplanes were structurally modified to incorporate load-limiting (energy-absorbing) subfloor concepts into the structure for full scale crash test evaluation and comparison to the unmodified airplane test results. Typically, the lowest floor accelerations and anthropomorphic dummy occupant responses, and the least seat crushing of standard and load-limiting seats, occurred in the modified load-limiting subfloor airplanes wherein the greatest structural crushing of the subfloor took place. The better performing of the two load-limiting subfloor concepts reduced the peak airplane floor accelerations at the pilot and four seat/occupant locations to -25 to -30 g's as compared to approximately -50 to -55 g's acceleration magnitude for the unmodified airplane structure.

  14. Towards an Improved Represenation of Reservoirs and Water Management in a Land Surface-Hydrology Model (United States)

    Yassin, F.; Anis, M. R.; Razavi, S.; Wheater, H. S.


    Water management through reservoirs, diversions, and irrigation have significantly changed river flow regimes and basin-wide energy and water balance cycles. Failure to represent these effects limits the performance of land surface-hydrology models not only for streamflow prediction but also for the estimation of soil moisture, evapotranspiration, and feedbacks to the atmosphere. Despite recent research to improve the representation of water management in land surface models, there remains a need to develop improved modeling approaches that work in complex and highly regulated basins such as the 406,000 km2 Saskatchewan River Basin (SaskRB). A particular challenge for regional and global application is a lack of local information on reservoir operational management. To this end, we implemented a reservoir operation, water abstraction, and irrigation algorithm in the MESH land surface-hydrology model and tested it over the SaskRB. MESH is Environment Canada's Land Surface-hydrology modeling system that couples Canadian Land Surface Scheme (CLASS) with hydrological routing model. The implemented reservoir algorithm uses an inflow-outflow relationship that accounts for the physical characteristics of reservoirs (e.g., storage-area-elevation relationships) and includes simplified operational characteristics based on local information (e.g., monthly target volume and release under limited, normal, and flood storage zone). The irrigation algorithm uses the difference between actual and potential evapotranspiration to estimate irrigation water demand. This irrigation demand is supplied from the neighboring reservoirs/diversion in the river system. We calibrated the model enabled with the new reservoir and irrigation modules in a multi-objective optimization setting. Results showed that the reservoir and irrigation modules significantly improved the MESH model performance in generating streamflow and evapotranspiration across the SaskRB and that this our approach provides

  15. Ultra-high accuracy optical testing: creating diffraction-limited short-wavelength optical systems

    International Nuclear Information System (INIS)

    Goldberg, Kenneth A.; Naulleau, Patrick P.; Rekawa, Senajith B.; Denham, Paul E.; Liddle, J. Alexander; Gullikson, Eric M.; Jackson, KeithH.; Anderson, Erik H.; Taylor, John S.; Sommargren, Gary E.; Chapman, Henry N.; Phillion, Donald W.; Johnson, Michael; Barty, Anton; Soufli, Regina; Spiller, Eberhard A.; Walton, Christopher C.; Bajt, Sasa


    Since 1993, research in the fabrication of extreme ultraviolet (EUV) optical imaging systems, conducted at Lawrence Berkeley National Laboratory (LBNL) and Lawrence Livermore National Laboratory (LLNL), has produced the highest resolution optical systems ever made. We have pioneered the development of ultra-high-accuracy optical testing and alignment methods, working at extreme ultraviolet wavelengths, and pushing wavefront-measuring interferometry into the 2-20-nm wavelength range (60-600 eV). These coherent measurement techniques, including lateral shearing interferometry and phase-shifting point-diffraction interferometry (PS/PDI) have achieved RMS wavefront measurement accuracies of 0.5-1-(angstrom) and better for primary aberration terms, enabling the creation of diffraction-limited EUV optics. The measurement accuracy is established using careful null-testing procedures, and has been verified repeatedly through high-resolution imaging. We believe these methods are broadly applicable to the advancement of short-wavelength optical systems including space telescopes, microscope objectives, projection lenses, synchrotron beamline optics, diffractive and holographic optics, and more. Measurements have been performed on a tunable undulator beamline at LBNL's Advanced Light Source (ALS), optimized for high coherent flux; although many of these techniques should be adaptable to alternative ultraviolet, EUV, and soft x-ray light sources. To date, we have measured nine prototype all-reflective EUV optical systems with NA values between 0.08 and 0.30 (f/6.25 to f/1.67). These projection-imaging lenses were created for the semiconductor industry's advanced research in EUV photolithography, a technology slated for introduction in 2009-13. This paper reviews the methods used and our program's accomplishments to date

  16. Advances in design and testing of limited angle optical diffraction tomographysystem for biological applications (United States)

    Kuś, A.; Makowski, P.; Kujawińska, M.


    Optical diffraction tomography has been steadily proving its potential to study one of the hot topics in modern cell biology -- 3D dynamic changes in cells' morphology represented with refractive index values. In this technique digital holography is combined with tomographic reconstruction and thus it is necessary to provide projections acquired at different viewing directions. Usually the Mach-Zehnder interferometer configuration is used and while the object beam performs scanning, the reference beam is in most cases stationary. This approach either limits possible scanning strategies or requires additional mechanical movement to be introduced in the reference beam. On the other hand, spiral or grid scanning is possible in alternative common-path or Michelson configurations. However, in this case there is no guarantee that a specimen is sparse enough for the object to interfere with an object-free part of the beam. In this paper we present a modified version of Mach-Zehnder interferometer-based tomographic microscope, in which both object and reference beam are subject to scanning using one scanning device only thus making any scanning scenario possible. This concept is realized with a custom-built optical system in the reference beam and is appropriate for mechanical as well as optical scanning. Usually, the tomographic reconstruction setups and algorithms are verified using a microsphere phantom, which is not enough to test the influence of the distribution of the projections. In this work we propose a more complex calibration object created using two-photon polymerization.

  17. U.S. Navy Unmanned Test Methods and Performance Limits for Underwater Breathing Apparatus (United States)


    examples will illustrate these approaches for scuba (Category 1), MK16 and Megalodon rebreathers (Category 4), MK 21, and KM 37 helmets (Category 2...both limits and goals. Grey: Met limits or goals but not both. Red (strikethrough): Exceeded limits. Example 4 Megalodon Rebreather...UBA in Helium Table 4-11 Megalodon in 1.3 ATA PO2 in Helium Green (bold): Met both limits and goals. Ventilation

  18. Development of a new biaxial testing system for generating forming limit diagrams for sheet metals under hot stamping conditions


    Shao, Z; Li, N; Lin, J; Dean, TA


    Conventional experimental approaches used to generate forming limit diagrams (FLDs) for sheet metals at different linear strain paths are not applicable to hot stamping and cold die quenching processes because cooling occurs prior to deformation and consistent values of heating rate, cooling rate, deformation temperature and strain rate are not easy to obtain. A novel biaxial testing system for use in a Gleeble testing machine has been adopted to generate forming limits of sheet metals, inclu...

  19. Large scale in-situ BOrehole and Geofluid Simulator (i.BOGS) for the development and testing of borehole technologies at reservoir conditions (United States)

    Duda, Mandy; Bracke, Rolf; Stöckhert, Ferdinand; Wittig, Volker


    A fundamental problem of technological applications related to the exploration and provision of geothermal energy is the inaccessibility of subsurface processes. As a result, actual reservoir properties can only be determined using (a) indirect measurement techniques such as seismic surveys, machine feedback and geophysical borehole logging, (b) laboratory experiments capable of simulating in-situ properties, but failing to preserve temporal and spatial scales, or vice versa, and (c) numerical simulations. Moreover, technological applications related to the drilling process, the completion and cementation of a wellbore or the stimulation and exploitation of the reservoir are exposed to high pressure and temperature conditions as well as corrosive environments resulting from both, rock formation and geofluid characteristics. To address fundamental and applied questions in the context of geothermal energy provision and subsurface exploration in general one of Europe's largest geoscientific laboratory infrastructures is introduced. The in-situ Borehole and Geofluid Simulator (i.BOGS) allows to simulate quasi scale-preserving processes at reservoir conditions up to depths of 5000 m and represents a large scale pressure vessel for iso-/hydrostatic and pore pressures up to 125 MPa and temperatures from -10°C to 180°C. The autoclave can either be filled with large rock core samples (25 cm in diameter, up to 3 m length) or with fluids and technical borehole devices (e.g. pumps, sensors). The pressure vessel is equipped with an ultrasound system for active transmission and passive recording of acoustic emissions, and can be complemented by additional sensors. The i.BOGS forms the basic module for the Match.BOGS finally consisting of three modules, i.e. (A) the i.BOGS, (B) the Drill.BOGS, a drilling module to be attached to the i.BOGS capable of applying realistic torques and contact forces to a drilling device that enters the i.BOGS, and (C) the Fluid.BOGS, a geofluid

  20. Transport of reservoir fines

    DEFF Research Database (Denmark)

    Yuan, Hao; Shapiro, Alexander; Stenby, Erling Halfdan

    Modeling transport of reservoir fines is of great importance for evaluating the damage of production wells and infectivity decline. The conventional methodology accounts for neither the formation heterogeneity around the wells nor the reservoir fines’ heterogeneity. We have developed an integral...


    African Journals Online (AJOL)

    Calls have been made to the government through various media to assist its populace in combating this nagging problem. It was concluded that sediment maximum accumulation is experienced in reservoir during the periods of maximum flow. Keywords: reservoir model, siltation, sediment, catchment, sediment transport. 1.

  2. Dynamic reservoir well interaction

    NARCIS (Netherlands)

    Sturm, W.L.; Belfroid, S.P.C.; Wolfswinkel, O. van; Peters, M.C.A.M.; Verhelst, F.J.P.C.M.


    In order to develop smart well control systems for unstable oil wells, realistic modeling of the dynamics of the well is essential. Most dynamic well models use a semi-steady state inflow model to describe the inflow of oil and gas from the reservoir. On the other hand, reservoir models use steady

  3. Reservoir Engineering Management Program

    Energy Technology Data Exchange (ETDEWEB)

    Howard, J.H.; Schwarz, W.J.


    The Reservoir Engineering Management Program being conducted at Lawrence Berkeley Laboratory includes two major tasks: 1) the continuation of support to geothermal reservoir engineering related work, started under the NSF-RANN program and transferred to ERDA at the time of its formation; 2) the development and subsequent implementation of a broad plan for support of research in topics related to the exploitation of geothermal reservoirs. This plan is now known as the GREMP plan. Both the NSF-RANN legacies and GREMP are in direct support of the DOE/DGE mission in general and the goals of the Resource and Technology/Resource Exploitation and Assessment Branch in particular. These goals are to determine the magnitude and distribution of geothermal resources and reduce risk in their exploitation through improved understanding of generically different reservoir types. These goals are to be accomplished by: 1) the creation of a large data base about geothermal reservoirs, 2) improved tools and methods for gathering data on geothermal reservoirs, and 3) modeling of reservoirs and utilization options. The NSF legacies are more research and training oriented, and the GREMP is geared primarily to the practical development of the geothermal reservoirs. 2 tabs., 3 figs.

  4. The Alphabet Soup of HIV Reservoir Markers. (United States)

    Sharaf, Radwa R; Li, Jonathan Z


    Despite the success of antiretroviral therapy in suppressing HIV, life-long therapy is required to avoid HIV reactivation from long-lived viral reservoirs. Currently, there is intense interest in searching for therapeutic interventions that can purge the viral reservoir to achieve complete remission in HIV patients off antiretroviral therapy. The evaluation of such interventions relies on our ability to accurately and precisely measure the true size of the viral reservoir. In this review, we assess the most commonly used HIV reservoir assays, as a clear understanding of the strengths and weaknesses of each is vital for the accurate interpretation of results and for the development of improved assays. The quantification of intracellular or plasma HIV RNA or DNA levels remains the most commonly used tests for the characterization of the viral reservoir. While cost-effective and high-throughput, these assays are not able to differentiate between replication-competent or defective fractions or quantify the number of infected cells. Viral outgrowth assays provide a lower bound for the fraction of cells that can produce infectious virus, but these assays are laborious, expensive and substantially underestimate the potential reservoir of replication-competent provirus. Newer assays are now available that seek to overcome some of these problems, including full-length proviral sequencing, inducible HIV RNA assays, ultrasensitive p24 assays and murine adoptive transfer techniques. The development and evaluation of strategies for HIV remission rely upon our ability to accurately and precisely quantify the size of the remaining viral reservoir. At this time, all current HIV reservoir assays have drawbacks such that combinations of assays are generally needed to gain a more comprehensive view of the viral reservoir. The development of novel, rapid, high-throughput assays that can sensitively quantify the levels of the replication-competent HIV reservoir is still needed.

  5. Application of integrated reservoir management and reservoir characterization to optimize infill drilling

    Energy Technology Data Exchange (ETDEWEB)



    This project has used a multi-disciplinary approach employing geology, geophysics, and engineering to conduct advanced reservoir characterization and management activities to design and implement an optimized infill drilling program at the North Robertson (Clearfork) Unit in Gaines County, Texas. The activities during the first Budget Period consisted of developing an integrated reservoir description from geological, engineering, and geostatistical studies, and using this description for reservoir flow simulation. Specific reservoir management activities were identified and tested. The geologically targeted infill drilling program currently being implemented is a result of this work. A significant contribution of this project is to demonstrate the use of cost-effective reservoir characterization and management tools that will be helpful to both independent and major operators for the optimal development of heterogeneous, low permeability shallow-shelf carbonate (SSC) reservoirs. The techniques that are outlined for the formulation of an integrated reservoir description apply to all oil and gas reservoirs, but are specifically tailored for use in the heterogeneous, low permeability carbonate reservoirs of West Texas.

  6. A reservoir operating method for riverine ecosystem protection, reservoir sedimentation control and water supply (United States)

    Yin, Xin-An; Yang, Zhi-Feng; Petts, Geoffrey E.; Kondolf, G. Mathias


    Riverine ecosystem protection requires the maintenance of natural flow and sediment regimes downstream from dams. In reservoir management schedules this requirement should be integrated with sedimentation control and human water supply. However, traditional eco-friendly reservoir operating methods have usually only considered the natural flow regime. This paper seeks to develop a reservoir operating method that accounts for both the natural flow and sediment regimes as well as optimizing the water supply allocations. Herein, reservoir water level (RWL), sediment-occupied ratio of reservoir volume (SOR) and rate of change of SOR (RCSOR) are adopted as three triggers of a drawdown-flushing-based sediment management policy. Two different groups of reservoir operating rule curves (RORCs) are designed for sediment-flushing and non-sediment-flushing years, and the three triggers, RWL, SOR and RCSOR, are used to change the “static” RORCs to “dynamic” ones. The approach is applied to the Wangkuai Reservoir, China to test its effectiveness. This shows that the approach can improve the flexibility of reservoir operators to balance the reservoir management, water supply management and the flow and sediment needs of the downstream riverine ecosystem.

  7. Matrix acidification in carbonate reservoirs; Acidificacoes matriciais em reservatorios carbonaticos

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Marcio de Oliveira [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil)


    Carbonate reservoirs are characterized by great diversity of its properties, including permeability and porosity. When submitted to matrix acidification, if no effort is employed, acid will tend to consume carbonates where permeability and porosity are higher, further increasing conductivity of these sites and also increasing permeability and porosity contrast existing before acid effects on formation. That would give limited production as result of small effective producer zone extent, with probable underutilization of potential reservoirs productivity. To overcome this effect and to achieve greater coverage of treatments, divergence techniques should be applied, including associations of them. This paper presents divergence techniques performed in matrix acidification of Campos and Espirito Santo basins wells, which represent great structural diversity and, as consequence, a significant range of situations. Formations tests results are analyzed to verify diversion systems effectiveness, and how they contribute to the growth of productive potential. (author)

  8. Reactive Tracers for Characterizing Fractured Geothermal Reservoirs (United States)

    Hawkins, Adam J.

    Multi-component tracer tests were conducted at a 10 x 10 m well field located in the Altona Flat Rocks of northern New York. Temperature advancement between two wells separated by 14 m was monitored throughout the well field during progressive heating of the reservoir over 6 d. Multiple approaches to predicting heat transport were applied to field data and compared to temperature rise recorded during reservoir heat-up. Tracer analysis incorporated both an analytical one-dimensional model and a two-dimensional numerical model for non-uniform fractures experiencing "flow-channeling." Modeling efforts demonstrated that estimating heat transfer surface area using a combined inert/adsorbing tracer (cesium-iodide) could provide accurate forecasting of premature thermal breakthrough. In addition, thermally degrading tracer tests were used to monitor inter-well temperature during progressive reservoir heating. Inert tracers alone were, in general, inadequate in forecasting thermal performance. In fact, moment analysis shows that, mathematically, thermal breakthrough is independent of parameters that primarily influence inert tracers. The most accurate prediction of thermal breakthrough using inert tracer alone was produced by treating hydrodynamic dispersion as a truly Fickian process with known and accurate mathematical models. Under this assumption, inert tracer data was matched by solving an inverse problem for non-uniform fracture aperture. Early arrival of the thermal front was predicted at the production, but was less accurate than using a combined inert/adsorbing tracer test. The spatial distribution of fluid flow paths in the plane of the fracture were identified using computational models, Fiber-Optic Distributed Temperature Sensing (FO-DTS), and Ground Penetrating Radar (GPR) imaging of saline tracer flow paths in the target fracture. Without exception, fluid flow was found to be concentrated in a roughly 1 m wide flow channel directly between the two wells. The

  9. D Modeling of Industrial Heritage Building Using COTSs System: Test, Limits and Performances (United States)

    Piras, M.; Di Pietra, V.; Visintini, D.


    The role of UAV systems in applied geomatics is continuously increasing in several applications as inspection, surveying and geospatial data. This evolution is mainly due to two factors: new technologies and new algorithms for data processing. About technologies, from some years ago there is a very wide use of commercial UAV even COTSs (Commercial On-The-Shelf) systems. Moreover, these UAVs allow to easily acquire oblique images, giving the possibility to overcome the limitations of the nadir approach related to the field of view and occlusions. In order to test potential and issue of COTSs systems, the Italian Society of Photogrammetry and Topography (SIFET) has organised the SBM2017, which is a benchmark where all people can participate in a shared experience. This benchmark, called "Photogrammetry with oblique images from UAV: potentialities and challenges", permits to collect considerations from the users, highlight the potential of these systems, define the critical aspects and the technological challenges and compare distinct approaches and software. The case study is the "Fornace Penna" in Scicli (Ragusa, Italy), an inaccessible monument of industrial architecture from the early 1900s. The datasets (images and video) have been acquired from three different UAVs system: Parrot Bebop 2, DJI Phantom 4 and Flytop Flynovex. The aim of this benchmark is to generate the 3D model of the "Fornace Penna", making an analysis considering different software, imaging geometry and processing strategies. This paper describes the surveying strategies, the methodologies and five different photogrammetric obtained results (sensor calibration, external orientation, dense point cloud and two orthophotos), using separately - the single images and the frames extracted from the video - acquired with the DJI system.


    Directory of Open Access Journals (Sweden)

    M. Piras


    Full Text Available The role of UAV systems in applied geomatics is continuously increasing in several applications as inspection, surveying and geospatial data. This evolution is mainly due to two factors: new technologies and new algorithms for data processing. About technologies, from some years ago there is a very wide use of commercial UAV even COTSs (Commercial On-The-Shelf systems. Moreover, these UAVs allow to easily acquire oblique images, giving the possibility to overcome the limitations of the nadir approach related to the field of view and occlusions. In order to test potential and issue of COTSs systems, the Italian Society of Photogrammetry and Topography (SIFET has organised the SBM2017, which is a benchmark where all people can participate in a shared experience. This benchmark, called “Photogrammetry with oblique images from UAV: potentialities and challenges”, permits to collect considerations from the users, highlight the potential of these systems, define the critical aspects and the technological challenges and compare distinct approaches and software. The case study is the “Fornace Penna” in Scicli (Ragusa, Italy, an inaccessible monument of industrial architecture from the early 1900s. The datasets (images and video have been acquired from three different UAVs system: Parrot Bebop 2, DJI Phantom 4 and Flytop Flynovex. The aim of this benchmark is to generate the 3D model of the “Fornace Penna”, making an analysis considering different software, imaging geometry and processing strategies. This paper describes the surveying strategies, the methodologies and five different photogrammetric obtained results (sensor calibration, external orientation, dense point cloud and two orthophotos, using separately – the single images and the frames extracted from the video – acquired with the DJI system.

  11. Using complementary methods to test whether marriage limits men's antisocial behavior. (United States)

    Jaffee, Sara R; Lombardi, Caitlin McPherran; Coley, Rebekah Levine


    Married men engage in significantly less antisocial behavior than unmarried men, but it is not clear whether this reflects a causal relationship. Instead, the relationship could reflect selection into marriage whereby the men who are most likely to marry (men in steady employment with high levels of education) are the least likely to engage in antisocial behavior. The relationship could also be the result of reverse causation, whereby high levels of antisocial behavior are a deterrent to marriage rather than the reverse. Both of these alternative processes are consistent with the possibility that some men have a genetically based proclivity to become married, known as an active genotype-environment correlation. Using four complementary methods, we tested the hypothesis that marriage limits men's antisocial behavior. These approaches have different strengths and weaknesses and collectively help to rule out alternative explanations, including active genotype-environment correlations, for a causal association between marriage and men's antisocial behavior. Data were drawn from the in-home interview sample of the National Longitudinal Study of Adolescent Health, a large, longitudinal survey study of a nationally representative sample of adolescents in the United States. Lagged negative binomial and logistic regression and propensity score matching models (n = 2,250), fixed-effects models of within-individual change (n = 3,061), and random-effects models of sibling differences (n = 618) all showed that married men engaged in significantly less antisocial behavior than unmarried men. Our findings replicate results from other quasiexperimental studies of marriage and men's antisocial behavior and extend the results to a nationally representative sample of young adults in the United States.

  12. On the Quasistatic Limit of Dynamic Evolutions for a Peeling Test in Dimension One (United States)

    Lazzaroni, Giuliano; Nardini, Lorenzo


    The aim of this paper is to study the quasistatic limit of a one-dimensional model of dynamic debonding. We start from a dynamic problem that strongly couples the wave equation in a time-dependent domain with Griffith's criterion for the evolution of the domain. Passing to the limit as inertia tends to zero, we find that the limit evolution satisfies a stability condition; however, the activation rule in Griffith's (quasistatic) criterion does not hold in general, thus the limit evolution is not rate-independent.

  13. Fracture Evolution Following a Hydraulic Stimulation within an EGS Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Mella, Michael [Univ. of Utah, Salt Lake City, UT (United States). Energy and Geoscience Inst.


    The objective of this project was to develop and demonstrate an approach for tracking the evolution of circulation immediately following a hydraulic stimulation in an EGS reservoir. Series of high-resolution tracer tests using conservative and thermally reactive tracers were designed at recently created EGS reservoirs in order to track changes in fluid flow parameters such as reservoir pore volume, flow capacity, and effective reservoir temperature over time. Data obtained from the project would be available for the calibration of reservoir models that could serve to predict EGS performance following a hydraulic stimulation.

  14. Reservoir rock permeability prediction using support vector regression in an Iranian oil field

    International Nuclear Information System (INIS)

    Saffarzadeh, Sadegh; Shadizadeh, Seyed Reza


    Reservoir permeability is a critical parameter for the evaluation of hydrocarbon reservoirs. It is often measured in the laboratory from reservoir core samples or evaluated from well test data. The prediction of reservoir rock permeability utilizing well log data is important because the core analysis and well test data are usually only available from a few wells in a field and have high coring and laboratory analysis costs. Since most wells are logged, the common practice is to estimate permeability from logs using correlation equations developed from limited core data; however, these correlation formulae are not universally applicable. Recently, support vector machines (SVMs) have been proposed as a new intelligence technique for both regression and classification tasks. The theory has a strong mathematical foundation for dependence estimation and predictive learning from finite data sets. The ultimate test for any technique that bears the claim of permeability prediction from well log data is the accurate and verifiable prediction of permeability for wells where only the well log data are available. The main goal of this paper is to develop the SVM method to obtain reservoir rock permeability based on well log data. (paper)

  15. Mathematical and field analysis of longitudinal reservoir infill (United States)

    Ke, W. T.; Capart, H.


    In reservoirs, severe problems are caused by infilled sediment deposits. In long term, the sediment accumulation reduces the capacity of reservoir storage and flood control benefits. In the short term, the sediment deposits influence the intakes of water-supply and hydroelectricity generation. For the management of reservoir, it is important to understand the deposition process and then to predict the sedimentation in reservoir. To investigate the behaviors of sediment deposits, we propose a one-dimensional simplified theory derived by the Exner equation to predict the longitudinal sedimentation distribution in idealized reservoirs. The theory models the reservoir infill geomorphic actions for three scenarios: delta progradation, near-dam bottom deposition, and final infill. These yield three kinds of self-similar analytical solutions for the reservoir bed profiles, under different boundary conditions. Three analytical solutions are composed by error function, complementary error function, and imaginary error function, respectively. The theory is also computed by finite volume method to test the analytical solutions. The theoretical and numerical predictions are in good agreement with one-dimensional small-scale laboratory experiment. As the theory is simple to apply with analytical solutions and numerical computation, we propose some applications to simulate the long-profile evolution of field reservoirs and focus on the infill sediment deposit volume resulting the uplift of near-dam bottom elevation. These field reservoirs introduced here are Wushe Reservoir, Tsengwen Reservoir, Mudan Reservoir in Taiwan, Lago Dos Bocas in Puerto Rico, and Sakuma Dam in Japan.

  16. Measuring the latent reservoir in vivo (United States)

    Massanella, Marta; Richman, Douglas D.


    Current efforts toward achieving a cure for HIV are focused on developing strategies to eliminate latently infected CD4+ T cells, which represent the major barrier to virus eradication. Sensitive, precise, and practical assays that can reliably characterize and measure this HIV reservoir and can reliably measure the impact of a candidate treatment strategy are essential. PCR-based procedures for detecting integrated HIV DNA will overestimate the size of the reservoir by detecting replication-incompetent proviruses; however, viral outgrowth assays underestimate the size of the reservoir. Here, we describe the attributes and limitations of current procedures for measuring the HIV reservoir. Characterizing their relative merits will require rigorous evaluation of their performance characteristics (sensitivity, specificity, reproducibility, etc.) and their relationship to the results of clinical studies. PMID:26829625

  17. Multi-data reservoir history matching for enhanced reservoir forecasting and uncertainty quantification

    KAUST Repository

    Katterbauer, Klemens


    Reservoir simulations and history matching are critical for fine-tuning reservoir production strategies, improving understanding of the subsurface formation, and forecasting remaining reserves. Production data have long been incorporated for adjusting reservoir parameters. However, the sparse spatial sampling of this data set has posed a significant challenge for efficiently reducing uncertainty of reservoir parameters. Seismic, electromagnetic, gravity and InSAR techniques have found widespread applications in enhancing exploration for oil and gas and monitoring reservoirs. These data have however been interpreted and analyzed mostly separately, rarely exploiting the synergy effects that could result from combining them. We present a multi-data ensemble Kalman filter-based history matching framework for the simultaneous incorporation of various reservoir data such as seismic, electromagnetics, gravimetry and InSAR for best possible characterization of the reservoir formation. We apply an ensemble-based sensitivity method to evaluate the impact of each observation on the estimated reservoir parameters. Numerical experiments for different test cases demonstrate considerable matching enhancements when integrating all data sets in the history matching process. Results from the sensitivity analysis further suggest that electromagnetic data exhibit the strongest impact on the matching enhancements due to their strong differentiation between water fronts and hydrocarbons in the test cases.

  18. An experimental unification of reservoir computing methods. (United States)

    Verstraeten, D; Schrauwen, B; D'Haene, M; Stroobandt, D


    Three different uses of a recurrent neural network (RNN) as a reservoir that is not trained but instead read out by a simple external classification layer have been described in the literature: Liquid State Machines (LSMs), Echo State Networks (ESNs) and the Backpropagation Decorrelation (BPDC) learning rule. Individual descriptions of these techniques exist, but a overview is still lacking. Here, we present a series of experimental results that compares all three implementations, and draw conclusions about the relation between a broad range of reservoir parameters and network dynamics, memory, node complexity and performance on a variety of benchmark tests with different characteristics. Next, we introduce a new measure for the reservoir dynamics based on Lyapunov exponents. Unlike previous measures in the literature, this measure is dependent on the dynamics of the reservoir in response to the inputs, and in the cases we tried, it indicates an optimal value for the global scaling of the weight matrix, irrespective of the standard measures. We also describe the Reservoir Computing Toolbox that was used for these experiments, which implements all the types of Reservoir Computing and allows the easy simulation of a wide range of reservoir topologies for a number of benchmarks.

  19. Sediment management for reservoir

    International Nuclear Information System (INIS)

    Rahman, A.


    All natural lakes and reservoirs whether on rivers, tributaries or off channel storages are doomed to be sited up. Pakistan has two major reservoirs of Tarbela and Managla and shallow lake created by Chashma Barrage. Tarbela and Mangla Lakes are losing their capacities ever since first impounding, Tarbela since 1974 and Mangla since 1967. Tarbela Reservoir receives average annual flow of about 62 MAF and sediment deposits of 0.11 MAF whereas Mangla gets about 23 MAF of average annual flows and is losing its storage at the rate of average 34,000 MAF annually. The loss of storage is a great concern and studies for Tarbela were carried out by TAMS and Wallingford to sustain its capacity whereas no study has been done for Mangla as yet except as part of study for Raised Mangla, which is only desk work. Delta of Tarbala reservoir has advanced to about 6.59 miles (Pivot Point) from power intakes. In case of liquefaction of delta by tremor as low as 0.12g peak ground acceleration the power tunnels I, 2 and 3 will be blocked. Minimum Pool of reservoir is being raised so as to check the advance of delta. Mangla delta will follow the trend of Tarbela. Tarbela has vast amount of data as reservoir is surveyed every year, whereas Mangla Reservoir survey was done at five-year interval, which has now been proposed .to be reduced to three-year interval. In addition suspended sediment sampling of inflow streams is being done by Surface Water Hydrology Project of WAPDA as also some bed load sampling. The problem of Chasma Reservoir has also been highlighted, as it is being indiscriminately being filled up and drawdown several times a year without regard to its reaction to this treatment. The Sediment Management of these reservoirs is essential and the paper discusses pros and cons of various alternatives. (author)

  20. Simulation of California's Major Reservoirs Outflow Using Data Mining Technique (United States)

    Yang, T.; Gao, X.; Sorooshian, S.


    The reservoir's outflow is controlled by reservoir operators, which is different from the upstream inflow. The outflow is more important than the reservoir's inflow for the downstream water users. In order to simulate the complicated reservoir operation and extract the outflow decision making patterns for California's 12 major reservoirs, we build a data-driven, computer-based ("artificial intelligent") reservoir decision making tool, using decision regression and classification tree approach. This is a well-developed statistical and graphical modeling methodology in the field of data mining. A shuffled cross validation approach is also employed to extract the outflow decision making patterns and rules based on the selected decision variables (inflow amount, precipitation, timing, water type year etc.). To show the accuracy of the model, a verification study is carried out comparing the model-generated outflow decisions ("artificial intelligent" decisions) with that made by reservoir operators (human decisions). The simulation results show that the machine-generated outflow decisions are very similar to the real reservoir operators' decisions. This conclusion is based on statistical evaluations using the Nash-Sutcliffe test. The proposed model is able to detect the most influential variables and their weights when the reservoir operators make an outflow decision. While the proposed approach was firstly applied and tested on California's 12 major reservoirs, the method is universally adaptable to other reservoir systems.

  1. Innovation-driven efficient development of the Longwangmiao Fm large-scale sulfur gas reservoir in Moxi block, Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Xinhua Ma


    Full Text Available The Lower Cambrian Longwangmiao Fm gas reservoir in Moxi block of the Anyue Gas field, Sichuan Basin, is the largest single-sandbody integrated carbonate gas reservoir proved so far in China. Notwithstanding this reservoir's advantages like large-scale reserves and high single-well productivity, there are multiple complicated factors restricting its efficient development, such as a median content of hydrogen sulfide, low porosity and strong heterogeneity of fracture–cave formation, various modes of gas–water occurrences, and close relation between overpressure and stress sensitivity. Up till now, since only a few Cambrian large-scale carbonate gas reservoirs have ever been developed in the world, there still exists some blind spots especially about its exploration and production rules. Besides, as for large-scale sulfur gas reservoirs, the exploration and construction is costly, and production test in the early evaluation stage is severely limited, all of which will bring about great challenges in productivity construction and high potential risks. In this regard, combining with Chinese strategic demand of strengthening clean energy supply security, the PetroChina Southwest Oil & Gas Field Company has carried out researches and field tests for the purpose of providing high-production wells, optimizing development design, rapidly constructing high-quality productivity and upgrading HSE security in the Longwangmiao Fm gas reservoir in Moxi block. Through the innovations of technology and management mode within 3 years, this gas reservoir has been built into a modern large-scale gas field with high quality, high efficiency and high benefit, and its annual capacity is now up to over 100 × 108 m3, with a desirable production capacity and development indexes gained as originally anticipated. It has become a new model of large-scale gas reservoirs with efficient development, providing a reference for other types of gas reservoirs in China.

  2. Elimination of Whole Effluent Toxicity NPDES Permit Limits through the Use of an Alternative Testing Species and Reasonable Potential Analysis

    International Nuclear Information System (INIS)

    PAYNE, W.L.


    The cladoceran, Ceriodaphnia dubia (C. dubia), is required by the State of South Carolina to be used in whole effluent toxicity (WET) compliance tests in order to meet limits contained within National Pollutant Discharge Elimination System (NPDES) permits. Westinghouse Savannah River Company (WSRC) experienced WET test failures for no clear reason over a long period of time. Toxicity identification examinations on effluents did not indicate the presence of toxicants; therefore, the WET test itself was brought under suspicion. Research was undertaken with an alternate cladoceran, Daphnia ambigua (D. ambigua). It was determined that this species survives better in soft water, so approval was obtained from regulating authorities to use this ''alternate'' species in WET tests. The result was better test results and elimination of non-compliances. The successful use of D. ambigua allowed WSRC to gain approval from the South Carolina Department of Health and Environmental Control (SCDHEC) to remove WET limits from the NPDES permit

  3. Reservoir characterization of Pennsylvanian sandstone reservoirs. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, M.


    This final report summarizes the progress during the three years of a project on Reservoir Characterization of Pennsylvanian Sandstone Reservoirs. The report is divided into three sections: (i) reservoir description; (ii) scale-up procedures; (iii) outcrop investigation. The first section describes the methods by which a reservoir can be described in three dimensions. The next step in reservoir description is to scale up reservoir properties for flow simulation. The second section addresses the issue of scale-up of reservoir properties once the spatial descriptions of properties are created. The last section describes the investigation of an outcrop.

  4. Tracer tests - possibilities and limitations. Experience from SKB fieldwork: 1977-2007

    Energy Technology Data Exchange (ETDEWEB)

    Loefgren, Martin; Crawford, James; Elert, Mark (Kemakta Konsult AB, Stockholm (SE))


    Tracer tests have played, and still play, a central role in investigations relating to the understanding of radionuclide retention processes in the field. At present there is a debate within the scientific community concerning how, and to what extent, tracer tests can be used to evaluate large-scale and long-term transport and retardation of radionuclides and other solutes of interest for Safety Assessment of repositories for spent nuclear fuel. In this report the SKB fieldwork on tracer tests performed at Swedish sites from 1977 to 2007 is described and discussed. Furthermore, the knowledge and process understanding evolved during the decades of radionuclide transport experiments and modelling within the SKB programme is summarised. One of the main objectives of this report is to discuss what data and knowledge can be extracted from different in situ tests in a robust fashion. Given the level of complexity associated with transport processes that may occur over the timescale of a tracer test, the utility of tracer tests is considered in the context of evidence-based interpretations of data which we characterise in the form of a sequence of questions of increasing complexity. The complexity of this sequence ranges from whether connection can be confirmed between injection and withdrawal points to whether quantitative data can be extrapolated from a tracer test to be subsequently used in Safety Assessment. The main findings of this report are that: Field scale tracer tests can confirm flow connectivity. Field scale tracer tests confirm the existence of retention. Field scale tracer tests alone can only broadly substantiate our process understanding. However, if performing extensive Site Characterisation and integrating the tracer test results with the full range of geoscientific information available, much support can be given to our process understanding. Field scale tracer tests can deliver the product of the material property group MPG and the F-factor, valid

  5. The Thermionic System Evaluation Test (TSET): Descriptions, limitations, and the involvement of the space nuclear power community

    International Nuclear Information System (INIS)

    Morris, D.B.


    Project and test planning for the Thermionic System Evaluation Test (TSET) Project began in August 1990. Since the formalization of the contract agreement two years ago, the TOPAZ-II testing hardware was delivered in May 1992. In the months since the delivery of the test hardware, Russians and Americans working side-by-side installed the equipment and are preparing to begin testing in early 1993. The procurement of the Russian TOPAZ-II unfueled thermionic space nuclear power system (SNP) provides a unique opportunity to understand a complete thermionic system and enhances the possibility for further study of this type of power conversion for space applications. This paper will describe the program and test article, facility and test article limitations, and how the government and industry are encouraged to be involved in the program

  6. Top-Down, Intelligent Reservoir Model (United States)

    Mohaghegh, Shahab


    Conventional reservoir simulation and modeling is a bottom-up approach. It starts with building a geological model of the reservoir that is populated with the best available petrophysical and geophysical information at the time of development. Engineering fluid flow principles are added and solved numerically so as to arrive at a dynamic reservoir model. The dynamic reservoir model is calibrated using the production history of multiple wells and the history matched model is used to strategize field development in order to improve recovery. Top-Down, Intelligent Reservoir Modeling approaches the reservoir simulation and modeling from an opposite angle by attempting to build a realization of the reservoir starting with the measured well production behavior (history). The production history is augmented by core, log, well test and seismic data in order to increase the accuracy of the Top-Down modeling technique. Although not intended as a substitute for the conventional reservoir simulation of large, complex fields, this novel approach to reservoir modeling can be used as an alternative (at a fraction of the cost) to conventional reservoir simulation and modeling in cases where performing conventional modeling is cost (and man-power) prohibitive. In cases where a conventional model of a reservoir already exists, Top-Down modeling should be considered as a compliment to, rather than a competition for the conventional technique, to provide an independent look at the data coming from the reservoir/wells for optimum development strategy and recovery enhancement. Top-Down, Intelligent Reservoir Modeling starts with well-known reservoir engineering techniques such as Decline Curve Analysis, Type Curve Matching, History Matching using single well numerical reservoir simulation, Volumetric Reserve Estimation and calculation of Recovery Factors for all the wells (individually) in the field. Using statistical techniques multiple Production Indicators (3, 6, and 9 months cum

  7. Testing and Prediction of Limits of Lubrication in Sheet Metal Forming

    DEFF Research Database (Denmark)

    Ceron, Ermanno; Bay, Niels


    Increasing focus on environmental issues in industrial production has urged a number of sheet metal forming companies to look for new tribo-systems, here meaning the combination of tool_material/workpiece_material/lubricant, in order to substitute hazardous lubricants such as chlorinated paraffin...... oils. Testing of new tribo-systems under production conditions is, however, very costly. For preliminary testing it is more feasible to introduce laboratory tests. In this paper a new methodology for testing new tribo-systems is presented. The methodology describes a series of investigations combining...... laboratory and production tests as well as numerical analyses in order to evaluate and compare performance of the new tribo-systems. A part is selected from industrial production and analyzed by this methodology in order to substitute the existing tribo-system with a new one....

  8. Greenhouse Gas Emissions from Reservoir Water Surfaces: A New Global Synthesis - journal (United States)

    Collectively, reservoirs are an important anthropogenic source of greenhouse gases (GHGs) to the atmosphere. Attempts to model reservoir GHG fluxes, however, have been limited by inconsistencies in methodological approaches and data availability. An increase in the number of pu...

  9. South Louisiana Enhanced Oil Recovery/Sequestration R&D Project Small Scale Field Tests of Geologic Reservoir Classes for Geologic Storage

    Energy Technology Data Exchange (ETDEWEB)

    Hite, Roger [Blackhorse Energy LLC, Houston, TX (United States)


    The project site is located in Livingston Parish, Louisiana, approximately 26 miles due east of Baton Rouge. This project proposed to evaluate an early Eocene-aged Wilcox oil reservoir for permanent storage of CO2. Blackhorse Energy, LLC planned to conduct a parallel CO2 oil recovery project in the First Wilcox Sand. The primary focus of this project was to examine and prove the suitability of South Louisiana geologic formations for large-scale geologic sequestration of CO2 in association with enhanced oil recovery applications. This was to be accomplished through the focused demonstration of small-scale, permanent storage of CO2 in the First Wilcox Sand. The project was terminated at the request of Blackhorse Energy LLC on October 22, 2014.

  10. Accelerated carbonation testing of mortar with supplementary cement materials. Limitation of the acceleration due to drying

    NARCIS (Netherlands)

    Visser, J.H.M.


    In the design stage of a concrete structure, decisions have to be made on how to fulfil the required service life and consequently, what concrete composition to use. Concrete compositions can be chosen on account of known performances but this will limit the choice of compositions and materials to

  11. Spin susceptibility as a test of unitary limit in disordered graphene systems (United States)

    Grosu, I.; Biter, T.-L.


    We analyzed the static spin susceptibility of graphene systems in the presence of disorder and a small energy gap. We considered the case of strong scatterers (unitary limit). The temperature and impurity concentration effects were analyzed. The critical value of the impurity concentration was calculated. The behavior of the spin susceptibility for different values of the impurity concentration is discussed.

  12. Quantification of Libby Reservoir Levels Needed to Maintain or Enhance Reservior Fisheries, 1984 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, Bradley B.


    We are evaluating the potential impacts of Libby Reservoir operation on the fishery in Libby Reservoir. The sampling program has been tested and modified to provide data for developing an understanding of how reservoir operation impacts the reservoir fishery. Temperature appears to be an important variable influenced by reservoir operation which regulates fish and fish food production and distribution. 39 refs., 21 figs., 19 tabs.


    Energy Technology Data Exchange (ETDEWEB)

    Joel Walls; M.T. Taner; Naum Derzhi; Gary Mavko; Jack Dvorkin


    We have developed and tested technology for a new type of direct hydrocarbon detection. The method uses inelastic rock properties to greatly enhance the sensitivity of surface seismic methods to the presence of oil and gas saturation. These methods include use of energy absorption, dispersion, and attenuation (Q) along with traditional seismic attributes like velocity, impedance, and AVO. Our approach is to combine three elements: (1) a synthesis of the latest rock physics understanding of how rock inelasticity is related to rock type, pore fluid types, and pore microstructure, (2) synthetic seismic modeling that will help identify the relative contributions of scattering and intrinsic inelasticity to apparent Q attributes, and (3) robust algorithms that extract relative wave attenuation attributes from seismic data. This project provides: (1) Additional petrophysical insight from acquired data; (2) Increased understanding of rock and fluid properties; (3) New techniques to measure reservoir properties that are not currently available; and (4) Provide tools to more accurately describe the reservoir and predict oil location and volumes. These methodologies will improve the industry's ability to predict and quantify oil and gas saturation distribution, and to apply this information through geologic models to enhance reservoir simulation. We have applied for two separate patents relating to work that was completed as part of this project.

  14. Opportunities and limitations in low earth subsonic testing for qualification of extraterrestrial supersonic parachute designs (United States)

    Steltzner, A.; Cruz, J.; Bruno, R.; Mitcheltree, R.


    Parachutes for Mars and other planetary missions often need to operate at supersonic speeds in very low density atmospheres. Flight testing of such parachutes at appropriate conditions in the Earth's atmosphere is possible at high altitudes.

  15. The limits of testing particle-mediated oxidative stress in vitro in predicting diverse pathologies; relevance for testing of nanoparticles

    Directory of Open Access Journals (Sweden)

    Gulumian Mary


    Full Text Available Abstract In vitro studies with particles are a major staple of particle toxicology, generally used to investigate mechanisms and better understand the molecular events underlying cellular effects. However, there is ethical and financial pressure in nanotoxicology, the new sub-specialty of particle toxicology, to avoid using animals. Therefore an increasing amount of studies are being published using in vitro approaches and such studies require careful interpretation. We point out here that 3 different conventional pathogenic particle types, PM10, asbestos and quartz, which cause diverse pathological effects, have been reported to cause very similar oxidative stress effects in cells in culture. We discuss the likely explanation and implications of this apparent paradox, and its relevance for testing in nanotoxicology.

  16. Theoretical frameworks for testing relativistic gravity. 5: Post-Newtonian limit of Rosen's theory (United States)

    Lee, D. L.; Caves, C. M.


    The post-Newtonian limit of Rosen's theory of gravity is evaluated and is shown to be identical to that of general relativity, except for the PPN parameter alpha sub 2, which is related to the difference in propagation speeds for gravitational and electromagnetic waves. Both the value of alpha sub 2 and the value of the Newtonian gravitational constant depend on the present cosmological structure of the Universe. If the cosmological structure has a specific but presumably special form, the Newtonian gravitational constant assumes its current value, alpha sub 2 is zero, the post-Newtonian limit of Rosen's theory is identical to that of general relativity--and standard solar system experiments cannot distinguish between the two theories.

  17. Theoretical frameworks for testing relativistic gravity. V - Post-Newtonian limit of Rosen's theory (United States)

    Lee, D. L.; Ni, W.-T.; Caves, C. M.; Will, C. M.


    The post-Newtonian limit of Rosen's theory of gravity is evaluated and is shown to be identical to that of general relativity, except for the post-Newtonian parameter alpha sub 2 (which is related to the difference in propagation speeds for gravitational and electromagnetic waves). Both the value of alpha sub 2 and the value of the Newtonian gravitational constant depend on the present cosmological structure of the Universe. If the cosmological structure has a specific (but presumably special) form, the Newtonian gravitational constant assumes its current value, alpha sub 2 is zero, the post-Newtonian limit of Rosen's theory is identical to that of general relativity - and standard solar system experiments cannot distinguish between the two theories.

  18. On the Limitations of Government Borrowing: A Framework for Empirical Testing


    James D. Hamilton; Marjorie A. Flavin


    This paper seeks to distinguish empirically between two views on the limitations of government borrowing. According to one view, nothing precludes the government from running a permanent budget deficit, paying interest due on the growing debt load simply by issuing new debt, An alternative perspective holds that creditors would be unwilling to purchase government debt unless the government made a credible commitment to balance its budget in present value terms. We show that distinguishing bet...

  19. Ploidy evolution in the yeast Saccharomyces cerevisiae: a test of the nutrient limitation hypothesis. (United States)

    Mable, B K


    The nutrient limitation hypothesis provides a nongenetic explanation for the evolution of life cycles that retain both haploid and diploid phases: differences in nutrient requirements and uptake allow haploids to override the potential genetic advantages provided by diploidy under certain nutrient limiting conditions. The relative fitness of an isogenic series of haploid, diploid and tetraploid yeast cells (Saccharomyces cerevisiae), which were also equivalent at the mating type locus, was measured. Fitness was measured both by growth rate against a common competitor and by intrinsic growth rate in isolated cultures, under four environmental conditions: (1) rich medium (YPD) at the preferred growth temperature (30 °C); (2) nutrient poor medium (MM) at 30 °C; (3) YPD at a nonpreferred temperature (37 °C); and (4) MM at 37 °C. In contrast to the predictions of the nutrient limitation hypothesis, haploids grew significantly faster than diploids under nutrient rich conditions, but there were no apparent differences between them when fitness was determined by relative competitive ability. In addition, temperature affected the relative growth of haploids and diploids, with haploids growing proportionately faster at higher temperatures. Tetraploids performed very poorly under all conditions compared. Cell geometric parameters were not consistent predictors of fitness under the conditions measured.

  20. Discussing race-related limitations of genomic testing for colon cancer risk: implications for education and counseling. (United States)

    Butrick, Morgan N; Vanhusen, Lauren; Leventhal, Kara-Grace; Hooker, Gillian W; Nusbaum, Rachel; Peshkin, Beth N; Salehizadeh, Yasmin; Pavlick, Jessica; Schwartz, Marc D; Graves, Kristi D


    This study examines communication about limitations of genomic results interpretation for colon cancer risk during education and counseling of minority participants. As part of a larger study conducted from 2010 to 2012, participants recruited from a large primary care clinic were offered testing for a research panel of 3 genomic markers (single nucleotide polymorphisms or SNPs) for colorectal cancer risk. Genetic counselors conducted pre- and post-test sessions which included discussion of limitations of result interpretation due to the lack of racial/ethnic diversity in research populations from which risk data are derived. Sessions were audio-recorded, transcribed and thematically analyzed. Many participants did not respond directly to this limitation. Among the participants that responded directly to this race-related limitation, many responses were negative. However, a few participants connected the limited minority information about SNPs with the importance of their current research participation. Genetic counselor discussions of this limitation were biomedically focused with limited explanations for the lacking data. The communication process themes identified included: low immediacy (infrequent use of language directly involving a participant), verbal dominance (greater speaking ratio of the counselor to the patient) and wide variation in the degree of interactivity (or the amount of turn-taking during the discussion). Placed within the larger literature on patient-provider communication, these present results provide insight into the dynamics surrounding race-related educational content for genomic testing and other emerging technologies. Clinicians may be better able to engage patients in the use of new genomic technology by increasing their awareness of specific communication processes and patterns during education or counseling sessions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Administration of neuropsychological tests using interactive voice response technology in the elderly: validation and limitations

    Directory of Open Access Journals (Sweden)

    Delyana Ivanova Miller


    Full Text Available Interactive voice response systems (IVR are computer programs, which interact with people to provide a number of services from business to health care. We examined the ability of an IVR system to administer and score a verbal fluency task (fruits and the digit span forward and backward in 158 community dwelling people aged between 65 and 92 years of age (full scale IQ of 68 to 134. Only 6 participants could not complete all tasks mostly due to early technical problems in the study. Participants were also administered the WAIS-IV and WMS-IV sub-tests. The IVR system correctly recognized 90% of the fruits in the verbal fluency task and 93-95% of the number sequences in the digit span. The IVR system typically underestimated the performance of participants because of voice recognition errors. In the digit span, these errors led to the erroneous discontinuation of the test: however the correlation between IVR scoring and clinical scoring was still high (93-95%. The correlation between the IVR verbal fluency and the WAIS-IV Similarities sub-test was 0.31. The correlation between the IVR digit span forward and backward and the in-person administration was 0.46. We discuss how valid and useful IVR systems are for neuropsychological testing in the elderly.

  2. Diagnostic Limitations of 13C-Mixed Triglyceride Breath Test in Patients after Cholecystectomy

    Directory of Open Access Journals (Sweden)

    V.I. Rusyn


    Full Text Available The results of a comprehensive examination of 136 patients after cholecystectomy are provided. High efficiency and informativeness of the 13C-mixed triglyceride breath test for determining exocrine pancreatic insufficiency at its early stages was noted in patients after cholecystectomy.

  3. Interpretive Issues with the Roberts Apperception Test for Children: Limitations of the Standardization Group. (United States)

    Bell, Nancy L.; Nagle, Richard J.


    Investigates the validity of the Roberts Apperception Test for Children (RATC) by examining the appropriateness of the standardization norms with other nonclinical samples. Findings suggest that the children in this study form a separate and distinct group from the well-adjusted children upon which the RATC scales were normed and supports previous…

  4. Accepting adoption's uncertainty: the limited ethics of pre-adoption genetic testing. (United States)

    Leighton, Kimberly J


    An increasing number of children are adopted in the United States from countries where both medical care and environmental conditions are extremely poor. In response to worries about the accuracy of medical histories, prospective adoptive parents increasingly request genetic testing of children prior to adoption. Though a general consensus on the ethics of pre-adoption genetic testing (PAGT) argues against permitting genetic testing on children available for adoption that is not also permitted for children in general, a view gaining traction argues for expanding the tests permitted. The reasoning behind this view is that the State has a duty to provide a child with parents who are the best "match," and thus all information that advances this end should be obtained. While the matching argument aims to promote the best interests of children, I show how it rests on the claim that what is in the best interests of children available for adoption is for prospective adoptive parents to have their genetic preferences satisfied such that the "genetics" of the children they end up adopting accurately reflects those preferences. Instead of protecting a vulnerable population, I conclude, PAGT contributes to the risks of harm such children face as it encourages people with strong genetic preferences to adopt children whose genetic backgrounds will always be uncertain.


    NARCIS (Netherlands)



    Selection of patients with lung cancer who are most likely to benefit from chemotherapeutic treatment would be a substantial step forward. Therefore, a prospective study in predictive chemosensitivity testing in vitro using the fast green assay (FGA) as developed by Weisenthal et al was carried out.

  6. Testing the Limits: The Purposes and Effects of Additional, External Elementary Mathematics Assessment (United States)

    Lombardi, Karen Ann


    This mixed-methods case study focuses on the third through fifth grade classrooms at a public elementary school in a Midwestern urban school district where the Northwest Evaluation Association's (NWEA) Measures of Academic Progress (MAP) assessment is being implemented. According to the school district, the goals of these tests are: to show…

  7. The value and limitations of rechallenge in the guinea pig maximization test

    DEFF Research Database (Denmark)

    Frankild, S; Basketter, D A; Andersen, Klaus Ejner


    with a repeated challenge. However, there exist few published rechallenge data and the guideline does not describe how rechallenge data should be interpreted. In this paper, we have used examples from published results to illustrate both the positive value and the limitations of repeated challenges, including...... animals. In conclusion, the data presented demonstrate that, as a tool for the investigation of skin sensitizing potential, the GPMT can benefit from an experienced scientific evaluation of rechallenge data, but that this information should not be treated in a mechanistic fashion....

  8. D-shaped configurations in FTU for testing liquid lithium limiter: Preliminary studies and experiments

    Directory of Open Access Journals (Sweden)

    G. Ramogida


    A possible alternative connection of the poloidal field coils in FTU is here proposed, with the aim of achieving a true X-point configuration with a magnetic single null well inside the plasma chamber and strike points on the lithium limiter. A preliminary assessment of this design allowed estimating the required power supply upgrade and showed its compatibility with the existing mechanical structure and cooling system, at least for plasmas with current up to 300 kA and flat-top duration up to 4s.


    Directory of Open Access Journals (Sweden)

    A. L. S. Araújo

    Full Text Available Abstract In the last decade, unstructured grids have been a very important step in the development of petroleum reservoir simulators. In fact, the so-called third generation simulators are based on Perpendicular Bisection (PEBI unstructured grids. Nevertheless, the use of PEBI grids is not very general when full anisotropic reservoirs are modeled. Another possibility is the use of the Element based Finite Volume Method (EbFVM. This approach has been tested for several reservoir types and in principle has no limitation in application. In this paper, we implement this approach in an in-house simulator called UTCOMP using four element types: hexahedron, tetrahedron, prism, and pyramid. UTCOMP is a compositional, multiphase/multi-component simulator based on an Implicit Pressure Explicit Composition (IMPEC approach designed to handle several hydrocarbon recovery processes. All properties, except permeability and porosity, are evaluated in each grid vertex. In this work, four case studies were selected to evaluate the implementation, two of them involving irregular geometries. Results are shown in terms of oil and gas rates and saturated gas field.

  10. Methicillin Resistant Staphylococcus aureus: Inconsistencies in Vancomycin Susceptibility Testing Methods, Limitations and Advantages of each Method. (United States)

    Himani; Agrawal, Charu; Madan, Molly; Pandey, Anita; Thakuria, Bhaskar


    Vancomycin may be ineffective against an increasing proportion of methicillin resistant Staphylococcus aureus (MRSA) with minimum inhibitory concentrations (MICs) well within the susceptible range. On the other hand it is common knowledge that determination of vancomycin MICs is method dependent. Therefore, given the apparent variability in vancomycin MIC results obtained with the different methods, the use of the vancomycin MIC to predict the outcome of serious S. aureus infections needs to take into account the method used and the results of studies using that particular method. Comparative study was carried out to evaluate the MICs obtained by BMD method, E-test, and Vitek 2 method and to detect inconsistencies in these vancomycin for 66 MRSA isolates obtained from various samples of patients attending the OPDs & IPDs within a period of one year. A comparative study was carried out to evaluate the MICs obtained by BMD method, E-test, and Vitek 2 method to detect vancomycin susceptibility in 66 clinical isolates of MRSA obtained from various samples of patients attending the OPDs & IPDs within a period of one year. The study was conducted in Department of Microbiology, Subharti Medical College, Meerut from January to December 2012. On determination of MICs for vancomycin for the MRSA isolates, all were identified as VSSA by BMD, E-Test & Vitek 2 methods. However, the vancomycin MIC values obtained by E-test correlated better with BMD method (correlation factor= 0.6727) than Vitek 2 (correlation factor=0.5316), indicating E-Test to be a better method for determination of vancomycin MICs as compared to Vitek 2. MRSA isolates with higher vancomycin MICs, even within the susceptibility range, are being observed more frequently which result in treatment failures with vancomycin. Because of the discrepancy that exists in vancomycin MIC results from different methods, the prediction of outcome of serious S.aureus infections should take into account the method used


    Energy Technology Data Exchange (ETDEWEB)

    Stephen C. Ruppel


    Despite declining production rates, existing reservoirs in the US contain large quantities of remaining oil and gas that constitute a huge target for improved diagnosis and imaging of reservoir properties. The resource target is especially large in carbonate reservoirs, where conventional data and methodologies are normally insufficient to resolve critical scales of reservoir heterogeneity. The objectives of the research described in this report were to develop and test such methodologies for improved imaging, measurement, modeling, and prediction of reservoir properties in carbonate hydrocarbon reservoirs. The focus of the study is the Permian-age Fullerton Clear Fork reservoir of the Permian Basin of West Texas. This reservoir is an especially appropriate choice considering (a) the Permian Basin is the largest oil-bearing basin in the US, and (b) as a play, Clear Fork reservoirs have exhibited the lowest recovery efficiencies of all carbonate reservoirs in the Permian Basin.

  12. Geothermal Reservoir Technology Research Program: Abstracts of selected research projects

    Energy Technology Data Exchange (ETDEWEB)

    Reed, M.J. (ed.)


    Research projects are described in the following areas: geothermal exploration, mapping reservoir properties and reservoir monitoring, and well testing, simulation, and predicting reservoir performance. The objectives, technical approach, and project status of each project are presented. The background, research results, and future plans for each project are discussed. The names, addresses, and telephone and telefax numbers are given for the DOE program manager and the principal investigators. (MHR)

  13. Quality specifications for the extra-analytical phase of laboratory testing: Reference intervals and decision limits. (United States)

    Ceriotti, Ferruccio


    Reference intervals and decision limits are a critical part of the clinical laboratory report. The evaluation of their correct use represents a tool to verify the post analytical quality. Four elements are identified as indicators. 1. The use of decision limits for lipids and glycated hemoglobin. 2. The use, whenever possible, of common reference values. 3. The presence of gender-related reference intervals for at least the following common serum measurands (besides obviously the fertility relate hormones): alkaline phosphatase (ALP), alanine aminotransferase (ALT), creatine kinase (CK), creatinine, gamma-glutamyl transferase (GGT), IgM, ferritin, iron, transferrin, urate, red blood cells (RBC), hemoglobin (Hb) and hematocrit (Hct). 4. The presence of age-related reference intervals. The problem of specific reference intervals for elderly people is discussed, but their use is not recommended; on the contrary it is necessary the presence of pediatric age-related reference intervals at least for the following common serum measurands: ALP, amylase, creatinine, inorganic phosphate, lactate dehydrogenase, aspartate aminotransferase, urate, insulin like growth factor 1, white blood cells, RBC, Hb, Hct, alfa-fetoprotein and fertility related hormones. The lack of such reference intervals may imply significant risks for the patients. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  14. [Global public health: international health is tested to its limits by the human influenza A epidemic]. (United States)

    Franco-Giraldo, Alvaro; Alvarez-Dardet, Carlos


    This article comes from the intense international pressure that follows a near-catastrophy, such as the human influenza A H1N1 epidemic, and the limited resources for confronting such events. The analysis covers prevailing 20th century trends in the international public health arena and the change-induced challenges brought on by globalization, the transition set in motion by what has been deemed the "new" international public health and an ever-increasing focus on global health, in the context of an international scenario of shifting risks and opportunities and a growing number of multinational players. Global public health is defined as a public right, based on a new appreciation of the public, a new paradigm centered on human rights, and altruistic philosophy, politics, and ethics that undergird the changes in international public health on at least three fronts: redefining its theoretical foundation, improving world health, and renewing the international public health system, all of which is the byproduct of a new form of governance. A new world health system, directed by new global public institutions, would aim to make public health a global public right and face a variety of staggering challenges, such as working on public policy management on a global scale, renewing and democratizing the current global governing structure, and conquering the limits and weaknesses witnessed by international health.

  15. Tracing fluid flow in geothermal reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Rose, P.E.; Adams, M.C. [Univ. of Utah, Salt Lake City, UT (United States)


    A family of fluorescent compounds, the polycyclic aromatic sulfonates, were evaluated for application in intermediate- and high-temperature geothermal reservoirs. Whereas the naphthalene sulfonates were found to be very thermally stable and reasonably detectable, the amino-substituted naphthalene sulfonates were found to be somewhat less thermally stable, but much more detectable. A tracer test was conducted at the Dixie Valley, Nevada, geothermal reservoir using one of the substituted naphthalene sulfonates, amino G, and fluorescein. Four of 9 production wells showed tracer breakthrough during the first 200 days of the test. Reconstructed tracer return curves are presented that correct for the thermal decay of tracer assuming an average reservoir temperature of 227{degrees}C. In order to examine the feasibility of using numerical simulation to model tracer flow, we developed simple, two-dimensional models of the geothermal reservoir using the numerical simulation programs TETRAD and TOUGH2. By fitting model outputs to measured return curves, we show that numerical reservoir simulations can be calibrated with the tracer data. Both models predict the same order of elution, approximate tracer concentrations, and return curve shapes. Using these results, we propose a method for using numerical models to design a tracer test.

  16. Use of adverse outcome pathways in chemical toxicity testing: potential advantages and limitations

    Directory of Open Access Journals (Sweden)

    Jaeseong Jeong


    Full Text Available Amid revolutionary changes in toxicity assessment brought about by increasing regulation of chemicals, adverse outcome pathways (AOPs have emerged as a useful framework to assess adverse effect of chemicals using molecular level effect, which aid in setting environmental regulation policies. AOPs are biological maps that describe mechanisms linking molecular initiating event to adverse outcomes (AOs at an individual level. Each AOP consists of a molecular initiating event, key events, and an AO. AOPs use molecular markers to predict endpoints currently used in risk assessment, promote alternatives to animal model-based test methods, and provide scientific explanations for the effects of chemical exposures. Moreover, AOPs enhance certainty in interpreting existing and new information. The application of AOPs in chemical toxicity testing will help shift the existing paradigm of chemical management based on apical endpoints toward active application of in silico and in vitro data.

  17. Characteristics of volcanic reservoirs and distribution rules of effective reservoirs in the Changling fault depression, Songliao Basin

    Directory of Open Access Journals (Sweden)

    Pujun Wang


    Full Text Available In the Songliao Basin, volcanic oil and gas reservoirs are important exploration domains. Based on drilling, logging, and 3D seismic (1495 km2 data, 546 sets of measured physical properties and gas testing productivity of 66 wells in the Changling fault depression, Songliao Basin, eruptive cycles and sub-lithofacies were distinguished after lithologic correction of the 19,384 m volcanic well intervals, so that a quantitative analysis was conducted on the relation between the eruptive cycles, lithologies and lithofacies and the distribution of effective reservoirs. After the relationship was established between lithologies, lithofacies & cycles and reservoir physical properties & oil and gas bearing situations, an analysis was conducted on the characteristics of volcanic reservoirs and the distribution rules of effective reservoirs. It is indicated that 10 eruptive cycles of 3 sections are totally developed in this area, and the effective reservoirs are mainly distributed at the top cycles of eruptive sequences, with those of the 1st and 3rd Members of Yingcheng Formation presenting the best reservoir properties. In this area, there are mainly 11 types of volcanic rocks, among which rhyolite, rhyolitic tuff, rhyolitic tuffo lava and rhyolitic volcanic breccia are the dominant lithologies of effective reservoirs. In the target area are mainly developed 4 volcanic lithofacies (11 sub-lithofacies, among which upper sub-lithofacies of effusive facies and thermal clastic sub-lithofacies of explosion lithofacies are predominant in effective reservoirs. There is an obvious corresponding relationship between the physical properties of volcanic reservoirs and the development degree of effective reservoirs. The distribution of effective reservoirs is controlled by reservoir physical properties, and the formation of effective reservoirs is influenced more by porosity than by permeability. It is concluded that deep volcanic gas exploration presents a good

  18. Management of occult adrenocorticotropin-secreting bronchial carcinoids: limits of endocrine testing and imaging techniques. (United States)

    Loli, P; Vignati, F; Grossrubatscher, E; Dalino, P; Possa, M; Zurleni, F; Lomuscio, G; Rossetti, O; Ravini, M; Vanzulli, A; Bacchetta, C; Galli, C; Valente, D


    The differential diagnosis and the identification of the source of ACTH in occult ectopic Cushing's syndrome due to a bronchial carcinoid still represents a challenge for the endocrinologist. We report our experience in six patients with occult bronchial carcinoid in whom extensive hormonal, imaging, and scintigraphic evaluation was performed. All patients presented with hypercortisolism associated with high plasma ACTH values. The CRH test and high dose dexamethasone suppression test suggested an ectopic source of ACTH in three of six patients. During bilateral inferior petrosal sinus sampling, none of the patients showed a central to peripheral ACTH gradient. At the time of diagnosis, none of the patients had radiological evidence of the ectopic source of ACTH, whereas pentetreotide scintigraphy identified the lesion in two of four patients. Finally, a chest computed tomography scan revealed the presence of a bronchial lesion in all patients, and pentetreotide scintigraphy identified four of six lesions. In all patients a bronchial carcinoid was found and removed. In one patient with scintigraphic evidence of residual disease after two operations, radioguided surgery, using a hand-held gamma probe after iv administration of radiolabeled pentetreotide, was performed; this allowed detection and removal of residual multiple mediastinal lymph node metastases. In conclusion, our data show that there is not a single endocrine test or imaging procedure accurate enough to diagnose and localize occult ectopic ACTH-secreting bronchial carcinoids. Radioguided surgery appears to be promising in the presence of multiple tumor foci and previous incomplete removal of the tumor.

  19. [Research progress on phosphorus budgets and regulations in reservoirs]. (United States)

    Shen, Xiao; Li, Xu; Zhang, Wang-shou


    Phosphorus is an important limiting factor of water eutrophication. A clear understanding of its budget and regulated method is fundamental for reservoir ecological health. In order to pro- mote systematic research further and improve phosphorus regulation system, the budget balance of reservoir phosphorus and its influencing factors were concluded, as well as conventional regulation and control measures. In general, the main phosphorus sources of reservoirs include upstream input, overland runoff, industrial and domestic wastewater, aquaculture, atmospheric deposition and sediment release. Upstream input is the largest phosphorus source among them. The principal output path of phosphorus is the flood discharge, the emission load of which is mainly influenced by drainage patterns. In addition, biological harvest also can export a fraction of phosphorus. There are some factors affecting the reservoir phosphorus balance, including reservoirs' function, hydrological conditions, physical and chemical properties of water, etc. Therefore, the phosphorus budgets of different reservoirs vary greatly, according to different seasons and regions. In order to reduce the phosphorus loading in reservoirs, some methods are carried out, including constructed wetlands, prefix reservoir, sediment dredging, biomanipulation, etc. Different methods need to be chosen and combined according to different reservoirs' characteristics and water quality management goals. Thus, in the future research, it is reasonable to highlight reservoir ecological characteristics and proceed to a complete and systematic analysis of the inherent complexity of phosphorus budget and its impact factors for the reservoirs' management. Besides, the interaction between phosphorus budget and other nutrients in reservoirs also needs to be conducted. It is fundamental to reduce the reservoirs' phosphorus loading to establish a scientific and improved management system based on those researches.

  20. [Testing of mutations in BRCA1 and BRCA2 genes in tumor tissues - possibilities and limitations]. (United States)

    Vošmiková, Hana; Ryška, Aleš; Sieglová, Kateřina; Laco, Jan


    Development of targeted cancer therapy is accompanied by a search for markers allowing prediction of response to the particular treatment. Recently, the interest is focused, among other neoplasms, also on the therapy of ovarian cancer using new inhibitors of poly (ADP-ribose) polymerase (PARP) proteins, nuclear enzymes involved in the repair of single-stranded DNA breaks. The greatest benefit from the administration of PARP inhibitors have patients with a deleterious or potentially deleterious germ-line or somatic mutation of BRCA1 or BRCA2, two genes responsible for repair of double stranded DNA breaks. There has been described a wide spectrum of mutations of BRCA 1/2, from point substitutions to large deletions, including sometimes even several exons of the gene.Unlike the testing of germ-line mutations provided for many years by the medical geneticists, somatic mutations in the tumor tissue have not been routinely tested so far. Detection of BRCA1/2 mutations in the tumor is significantly different from testing of germ-line mutations. In comparison with the analysis of DNA isolated from blood samples, testing of DNA isolated from the FFPE tissue encounters challenges based on heterogeneous representation of tumor cells in the tissue samples, on the presence of multiple neoplastic clones and on the infiltration of tissue by the non-neoplastic elements, as well as difficulties caused by variable proportion of apoptotic and necrotic cells deteriorating the overall quality of isolated DNA.Regarding the testing methods, NGS appears to be the optimal choice because of its complexity, speed of implementation into routine diagnostics as well as sensitivity for detection of a BRCA 1/2 mutations. When introduced into everyday laboratory practice, the functioning quality control system is of utmost importance. Provided there is a high probability of detection of the so far unreported variations in BRCA 1/2 genes, an introduction of a shared database of somatic variants

  1. Optimising reservoir operation

    DEFF Research Database (Denmark)

    Ngo, Long le

    Anvendelse af optimeringsteknik til drift af reservoirer er blevet et væsentligt element i vandressource-planlægning og -forvaltning. Traditionelt har reservoirer været styret af heuristiske procedurer for udtag af vand, suppleret i en vis udstrækning af subjektive beslutninger. Udnyttelse af...... reservoirer involverer en lang række interessenter med meget forskellige formål (f.eks. kunstig vanding, vandkraft, vandforsyning mv.), og optimeringsteknik kan langt bedre lede frem til afbalancerede løsninger af de ofte modstridende interesser. Afhandlingen foreslår en række tiltag, hvormed traditionelle...... driftsstrategier kan erstattes af optimale strategier baseret på den nyeste udvikling indenfor computer-baserede beregninger. Hovedbidraget i afhandlingen er udviklingen af et beregningssystem, hvori en simuleringsmodel er koblet til en model for optimering af nogle udvalgte beslutningsvariable, der i særlig grad...

  2. Some potentials and limits of the leucocrit test as a fish health assessment method (United States)

    Wedemeyer, G.A.; Gould, R.W.; Yasutake, W.T.


    The sensitivity of the leucocrit as a stress tolerance and fish health assessment method was evaluated by subjecting juvenile coho salmon, Oncorhynchus kisutch, or steelhead trout, Salmo gairdneri, to standardized crowding, handling, temperature and disease challenges. The leucocrit was a sensitive indicator of the physiological stress resulting from crowding at population densities of 0·2–0·4 kg l−1, and to the stress of handling and to temperature changes. It was relatively insensitive to physiological sampling procedures which supports its continued development as a stress assessment method.In the case of fish diseases, subclinical or active Renibacterium salmoninarum and Yersinia ruckeriinfections had essentially no effect on leucocrit values. In contrast, active Aeromonas salmonicidainfections significantly depressed the leucocrit. However, no change was seen during the subclinical (incubation) phase prior to the development of an epizootic. Thus, the potential of the leucocrit as a fish health assessment method appears limited.

  3. Uncertainty based analysis of the impact of watershed phosphorus load on reservoir phosphorus concentration (United States)

    Karamouz, Mohammad; Taheriyoun, Masoud; Seyedabadi, Mohammadreza; Nazif, Sara


    In many regions of the world that depend on surface reservoirs as a source of water supply, eutrophication is a major water quality problem. Developing simulation models to evaluate the impact of watershed nutrient loads on the reservoir's water quality is an essential step in eutrophication management. In this regard, analysis of model uncertainty gives an opportunity to assess the reliability and the margin of safety of the model predictions for Total Maximum Daily Load (TMDL) from the watershed nutrient load. In this study, a computational procedure has been proposed for the analysis of the model uncertainties in simulation of watershed phosphorous load and reservoir phosphorous concentration. Data from the Aharchai watershed which is located upstream of the Satarkhan reservoir in the northwestern part of Iran, is used as the study area to test the effectiveness of the proposed methodology. The Soil and Water Assessment Tools (SWAT) is utilized for assessment of watershed phosphorus load as the main agent resulting in the reservoir eutrophication in the region. The most effective parameters in model performance are identified by a global sensitivity analysis technique named modified Fourier Amplitude Sensitivity Test (FAST) which can incorporate parameter interdependencies. The Generalized Likelihood Uncertainty Estimation (GLUE) technique is also applied to set up behavioral ranges of the parameters that are relevant to the actual observations. Finally, the cumulative weighted-likelihood distribution functions (CWLDF) are derived for outputs of the SWAT. They are used jointly for estimation of results uncertainty limits using the Copula method. To assess the effectiveness of applying Best Management Practices (BMPs) in the watershed, two scenarios of with and without BMPs application are tested. The results showed the effectiveness of the proposed model in uncertainty estimation of watershed phosphorus load and reservoir phosphorus concentration as well as the

  4. Short communication: Detection limits of non-beta-lactam antibiotics in goat's milk by microbiological residues screening tests. (United States)

    Sierra, D; Contreras, A; Sánchez, A; Luengo, C; Corrales, J C; Morales, C T; de la Fe, C; Guirao, I; Gonzalo, C


    This study compares the performance of 4 antimicrobial residue screening tests [brilliant black reduction test AiM (Analytik in Milch Produktions- und Vertriebs GmbH, München, Germany), Delvotest MCS (DSM Food Specialties, Delft, the Netherlands), Eclipse 100 test (ZEU-Inmunotec SL, Zaragoza, Spain), and Copan Milk Test (Copan Italia S.p.a., Brescia, Italy)] used to detect 20 antimicrobial agents (aminoglycosides, macrolides, tetracyclines, sulfonamides, and quinolones) in goat's milk, according to International Dairy Federation guidelines. Composite milk samples from 30 antibiotic-free goats were used to prepare spiked milk samples and 11,520 analytical determinations were carried out. According to a logistic regression model, agreement coefficients were greater than 98% for most of the antibiotics, with higher b values obtained for macrolides. Neither tetracyclines nor quinolones were detected at European Union maximum residue limits. Only the Copan Milk Test and the Delvotest MCS were able to detect 3 antimicrobials below their maximum residue limits (neomycin, tylosin, and sulfadimethoxine). Given that these tests are used in control programs for goat's milk, our results indicate their sensitivity would need to be improved to guarantee safety for consumers.

  5. Well-test analysis for gas hydrate reservoirs : examination of parameters suggested by conventional analysis for the JAPEX/JNOC/GSC et al. Mallik 5L-38 gas hydrate production research well

    Energy Technology Data Exchange (ETDEWEB)

    Kurihara, M.; Funatsu, K. [Japan Oil Engineering Co., Tokyo (Japan); Kusaka, K.; Yasuda, M. [Japan National Oil Corp., Chiba (Japan); Dallimore, S.R. [Geological Survey of Canada, Pacific Geoscience Centre, Sidney, BC (Canada); Collett, T.S. [United States Geological Survey, Denver, CO (United States); Hancock, S.H. [APA Petroleum Engineering Ltd., Calgary, AB (Canada)


    Formation tests were conducted with a Modular Formation Dynamics Tester (MDT) tool during the Mallik 2002 Gas Hydrate Production Research Well Program. Conventional pressure-transient test analysis methods were used to analyze the test results. However, it was noted that the reliability of the reservoir-parameter estimates is uncertain due to the abrupt change in gas hydrate saturation associated with gas hydrate dissociation during the tests. In order to examine the appropriateness of these methods, the bottom-hole pressure responses during MDT tests in the hypothetical and actual gas hydrate zones were predicted using a numerical simulator. They were then analyzed by conventional test-analysis methods. It was determined that the conventional methods may indicate the average effective permeability over the area of the gas hydrate dissociation. However, the study also revealed that conventional methods might accurately indicate the radius of gas hydrate dissociation only when applying appropriate multiphase-fluid properties and production rates to the cases with high gas hydrate saturation.

  6. Geothermal reservoir engineering

    CERN Document Server

    Grant, Malcolm Alister


    As nations alike struggle to diversify and secure their power portfolios, geothermal energy, the essentially limitless heat emanating from the earth itself, is being harnessed at an unprecedented rate.  For the last 25 years, engineers around the world tasked with taming this raw power have used Geothermal Reservoir Engineering as both a training manual and a professional reference.  This long-awaited second edition of Geothermal Reservoir Engineering is a practical guide to the issues and tasks geothermal engineers encounter in the course of their daily jobs. The bo

  7. Session: Reservoir Technology

    Energy Technology Data Exchange (ETDEWEB)

    Renner, Joel L.; Bodvarsson, Gudmundur S.; Wannamaker, Philip E.; Horne, Roland N.; Shook, G. Michael


    This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of five papers: ''Reservoir Technology'' by Joel L. Renner; ''LBL Research on the Geysers: Conceptual Models, Simulation and Monitoring Studies'' by Gudmundur S. Bodvarsson; ''Geothermal Geophysical Research in Electrical Methods at UURI'' by Philip E. Wannamaker; ''Optimizing Reinjection Strategy at Palinpinon, Philippines Based on Chloride Data'' by Roland N. Horne; ''TETRAD Reservoir Simulation'' by G. Michael Shook

  8. The limits to pride: A test of the pro-anorexia hypothesis. (United States)

    Cornelius, Talea; Blanton, Hart


    Many social psychological models propose that positive self-conceptions promote self-esteem. An extreme version of this hypothesis is advanced in "pro-anorexia" communities: identifying with anorexia, in conjunction with disordered eating, can lead to higher self-esteem. The current study empirically tested this hypothesis. Results challenge the pro-anorexia hypothesis. Although those with higher levels of pro-anorexia identification trended towards higher self-esteem with increased disordered eating, this did not overcome the strong negative main effect of pro-anorexia identification. These data suggest a more effective strategy for promoting self-esteem is to encourage rejection of disordered eating and an anorexic identity.

  9. Administration of neuropsychological tests using interactive voice response technology in the elderly: validation and limitations. (United States)

    Miller, Delyana Ivanova; Talbot, Vincent; Gagnon, Michèle; Messier, Claude


    Interactive voice response (IVR) systems are computer programs, which interact with people to provide a number of services from business to health care. We examined the ability of an IVR system to administer and score a verbal fluency task (fruits) and the digit span forward and backward in 158 community dwelling people aged between 65 and 92 years of age (full scale IQ of 68-134). Only six participants could not complete all tasks mostly due to early technical problems in the study. Participants were also administered the Wechsler Intelligence Scale fourth edition (WAIS-IV) and Wechsler Memory Scale fourth edition subtests. The IVR system correctly recognized 90% of the fruits in the verbal fluency task and 93-95% of the number sequences in the digit span. The IVR system typically underestimated the performance of participants because of voice recognition errors. In the digit span, these errors led to the erroneous discontinuation of the test: however the correlation between IVR scoring and clinical scoring was still high (93-95%). The correlation between the IVR verbal fluency and the WAIS-IV Similarities subtest was 0.31. The correlation between the IVR digit span forward and backward and the in-person administration was 0.46. We discuss how valid and useful IVR systems are for neuropsychological testing in the elderly.

  10. Are Geotehrmal Reservoirs Stressed Out? (United States)

    Davatzes, N. C.; Laboso, R. C.; Layland-Bachmann, C. E.; Feigl, K. L.; Foxall, W.; Tabrez, A. R.; Mellors, R. J.; Templeton, D. C.; Akerley, J.


    Crustal permeability can be strongly influenced by developing connected networks of open fractures. However, the detailed evolution of a fracture network, its extent, and the persistence of fracture porosity are difficult to analyze. Even in fault-hosted geothermal systems, where heat is brought to the surface from depth along a fault, hydrothermal flow is heterogeneously distributed. This is presumably due to variations in fracture density, connectivity, and attitude, as well as variations in fracture permeability caused by sealing of fractures by precipitated cements or compaction. At the Brady Geothermal field in Nevada, we test the relationship between the modeled local stress state perturbed by dislocations representing fault slip or volume changes in the geothermal reservoir inferred from surface deformation measured by InSAR and the location of successful geothermal wells, hydrothermal activity, and seismicity. We postulate that permeability is favored in volumes that experience positive Coulomb stress changes and reduced compression, which together promote high densities of dilatant fractures. Conversely, permeability can be inhibited in locations where Coulomb stress is reduced, compression promotes compaction, or where the faults are poorly oriented in the stress field and consequently slip infrequently. Over geologic time scales spanning the development of the fault system, these local stress states are strongly influenced by the geometry of the fault network relative to the remote stress driving slip. At shorter time scales, changes in fluid pressure within the fracture network constituting the reservoir cause elastic dilations and contractions. We integrate: (1) direct observations of stress state and fractures in boreholes and the mapped geometry of the fault network; (2) evidence of permeability from surface hydrothermal features, production/injection wells and surface deformations related to pumping history; and (3) seismicity to test the

  11. Fracture characterization in a deep geothermal reservoir (United States)

    Rühaak, Wolfram; Hehn, Vera; Hassanzadegan, Alireza; Tischner, Torsten


    At the geothermal research drilling Horstberg in North West Germany studies for the characterization of a vertical fracture are performed. The fracture was created by a massive hydraulic stimulation in 2003 in approx. 3700 m depth within rocks of the middle Buntsandstein. The fracture surface is in the order of 100,000 m2, depending on the flow rate at which water is injected. Besides hydraulic characterization, multiple tracer tests are planned. At the depth of interest the reservoir temperature is around 150 °C, pressure is around 600 bar (60 MPa) and due to salinity the water density is around 1200 kg/m3. Knowledge of tracer stability and behavior at these reservoir conditions is limited. Additionally, the planned tracer tests will be performed within one single borehole. In a closed cycle water is injected into the inner pipe of the well (tubing), which is separated by a permanent packer from the outer pipe (annulus). The water is produced back from the annulus approximately 150 m above the injection point. Thus, the circulation of thermal water between two sandstone layers via an artificial fracture can be achieved. Tests will be carried out with different flow rates and accordingly with different pressures, resulting in different fracture areas. Due to this test setup tracer signals will be stacked and will remain for a longer time in the fracture - which is the reason why different tracers are required. For an optimal characterization both conservative and reactive tracers will be used and different injection methods (continuous, instantaneous and pulsed) will be applied. For a proper setup of the tracer test numerical modelling studies are performed in advance. The relevant thermal, hydraulic and chemical processes (mainly adsorption and degredation) are coupled, resulting in a THC model; additionally the dependence of fracture aperture and area on fluid pressure has to be considered. Instead of applying a mechanically coupled model (THMC) a simplified

  12. Pulmonary Disease due to Mycobacterium tuberculosis in a Horse: Zoonotic Concerns and Limitations of Antemortem Testing

    Directory of Open Access Journals (Sweden)

    Konstantin P. Lyashchenko


    Full Text Available A case of pulmonary tuberculosis caused by Mycobacterium tuberculosis was diagnosed in a horse. Clinical evaluation performed prior to euthanasia did not suggest tuberculosis, but postmortem examination provided pathological and bacteriological evidence of mycobacteriosis. In the lungs, multiple tuberculoid granulomas communicating with the bronchiolar lumen, pleural effusion, and a granulomatous lymphadenitis involving mediastinal and tracheobronchial lymph nodes were found. Serologic response to M. tuberculosis antigens was detected in the infected horse, but not in the group of 42 potentially exposed animals (18 horses, 14 alpacas, 6 donkeys, and 4 dogs which showed no signs of disease. Diagnosis of tuberculosis in live horses remains extremely difficult. Four of 20 animal handlers at the farm were positive for tuberculous infection upon follow-up testing by interferon-gamma release assay, indicating a possibility of interspecies transmission of M. tuberculosis.

  13. A continuous-flow periphyton bioassay: tests of nutrient limitation in a tundra stream

    International Nuclear Information System (INIS)

    Peterson, B.J.; Hobbie, J.E.; Corliss, T.L.; Kriet, K.


    The effect of added nutrients on the periphyton of a tundra stream was tested during July and August. Flow-through systems consisting of a bank of clear plastic tubes containing racks of microscope slides were suspended from floats in the stream. Nutrients were enriched in the experimental tubes by siphoning concentrated nutrient solutions from Mariotte bottles into the upstream end of each tube. Slides from each tube were assayed at 2-6 day intervals for chlorophyll content and photosynthetic 14 CO 2 uptake. Levels of chlorophyll and CO 2 uptake were significantly higher than the controls both in the tubes with 10μg PO 4 -P>liter -1 of stream water and in those with P plus 100 μg NH 4 NO 3 -N.liter. Nitrogen alone gave no stimulation

  14. Limitations of widely used high-risk human papillomavirus laboratory-developed testing in cervical cancer screening

    Directory of Open Access Journals (Sweden)

    Nance KV


    Full Text Available Keith V Nance Medical Directory of Cytology, Rex Hospital, Raleigh, and Department of Pathology, The University of North Carolina School of Medicine, Chapel Hill, NC, USAI read with interest the recently published article by Naryshkin and Austin entitled "Limitations of widely used high-risk human papillomavirus laboratory-developed testing in cervical cancer screening".1 The article is a single case report of squamous cell carcinoma of the cervix diagnosed in a patient who had negative Hybrid Capture 2 (Qiagen NV, Hilden, Germany high-risk human papillomavirus testing from SurePath™ (Becton-Dickinson, Franklin Lakes, NJ samples. The authors then discuss several valid points regarding the use of human papillomavirus testing and cervical cancer screening not approved by the US Food and Drug Administration (FDA. Their conclusion is that such testing should not be done using the SurePath collection medium.View the original paper by Naryshkin and Austin.

  15. Estimation of reservoir fluid volumes through 4-D seismic analysis on Gullfaks

    Energy Technology Data Exchange (ETDEWEB)

    Veire, H.S.; Reymond, S.B.; Signer, C.; Tenneboe, P.O.; Soenneland, L.; Schlumberger, Geco-Prakla


    4-D seismic has the potential to monitor hydrocarbon movement in reservoirs during production, and could thereby supplement the predictions of reservoir parameters offered by the reservoir simulator. However 4-D seismic is often more band limited than the vertical resolution required in the reservoir model. As a consequence the seismic data holds a composite response from reservoir parameter changes during production so that the inversion becomes non-unique. A procedure where data from the reservoir model are integrated with seismic data will be presented. The potential of such a procedure is demonstrated through a case study from a recent 4-D survey over the Gullfaks field. 2 figs.

  16. H/sub. cap alpha. / monitors for the Advanced Limiter Test-II (ALT-II) on TEXTOR

    Energy Technology Data Exchange (ETDEWEB)

    Uckan, T.


    The H/sub ..cap alpha../ monitor system installed on TEXTOR in conjunction with the Advanced Limiter Test-II (ALT-II) toroidal belt pump limiter is introduced. The monitors are used to study edge particle fluxes and recycling, correlations to confinement properties of core and edge plasma with ALT-II, and also high-power auxiliary heating (/approximately/5 MW) during long-pulse (/approximately/4-s) operation of TEXTOR. A model of the edge particle flux based on the H/sub ..cap alpha../ measurements is presented. The ALT-II experiments are to be carried out in various phases. Here we discuss the results obtained from the monitor system during the initial phase of operations following the installation of the ALT-II limiter, with ohmic heating only. 15 refs., 21 figs.

  17. Integral cesium reservoir: Design and transient operation (United States)

    Smith, Joe N., Jr.; Horner, M. Harlan; Begg, Lester L.; Wrobleski, William J.

    An electrically heated thermionic converter has been designed built and successfully tested in air. One of the unique features of this converter was an integral cesium reservoir thermally coupled to the emitter. The reservoir consisted of fifteen cesiated graphite pins located in pockets situated in the emitter lead with thermal coupling to the emitter, collector and the emitter terminal; there were no auxiliary electric heaters on the reservoir. Test results are described for conditions in which the input thermal power to the converter was ramped up and down between 50% and 100% of full power in times as short as 50 sec, with data acquisition occurring every 12 sec. During the ramps the emitter and collector temperature profiles. the reservoir temperature and the electric output into a fixed load resistor are reported. The converter responded promptly to the power ramps without excessive overshoot and with no tendency to develop instabilities. This is the rust demonstration of the performance of a cesium-graphite integral reservoir in a fast transient.

  18. Reservoir sizing using inert and chemically reacting tracers

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, B.A.; Tester, J.W.; Brown, L.F.


    Non-reactive tracer tests in prototype hot dry rock (HDR) geothermal reservoirs indicate multiple fracture flow paths that show increases in volume due to energy extraction. Tracer modal volumes correlate roughly with estimated reservoir heat-transfer capacity. Chemically reactive tracers are proposed which will map the rate of advance of the cooled region of an HDR reservoir, providing advanced warning of thermal drawdown. Critical parameters are examined using a simplified reservoir model for screening purposes. Hydrolysis reactions are a promising class of reactions for this purpose.

  19. Overtopping of Rubble Mound Breakwaters with Front Reservoir

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Andersen, Thomas Lykke


    The design and performance of breakwaters with front reservoir are discussed on the basis of physical 2-D model tests with a number of cross sections, in which vertopping discharge and spatial distribution, wave forces on inner parapet walls, and stability of reservoir armour were studied....... The sensitivity of these quantities to the width of the reservoir is discussed. It is demonstrated that front reservoir solutions are more economical than conventional cross section solutions, such as bermed structures and mild slope structures, in cases where low crests and small overtopping discharges...

  20. The glaciogenic reservoir analogue studies project (GRASP)

    DEFF Research Database (Denmark)

    Moscariello, A.; Moreau, Julien; Vegt, P. van der

    increasing the risk associated with developing effectively these reservoirs. Therefore a analogue-based predictive stratigraphical and sedimentological model can help to steer drilling strategy and reduce uncertainties and associated risks. For this purpose the GRASP joint industry programme was established......Tunnel galleys are common features in Palaeozoic glacigenic succession in North Afrcica and Middle East and they are amongst the most challenging target for hydrocarbon exploration and developing drilling in these regions. Similarly, these buried valleys form important groundwater reservoirs...... in Quaternary glaciated areas and their nature and sediment composition is critical to drive a sustainable production strategy and assess their vulnerability. Seismic resolution however, often limits the understanding of channel valleys morphology, 3D geometry and internal reservoir distribution, thus...

  1. Potosi Reservoir Modeling; History and Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Valerie; Leetaru, Hannes


    from using data from a single well in 2010 to the inclusion of data from three wells in 2013 which largely leverage the porosity and permeability logs plus knowledge of lost circulation zones. The first Potosi model (Potosi Geobody Model 2010) attempted to use the available seismic inversion data to inform the geomodel and predict vugular zones in advance of drilling VW1. Lost circulation zones in VW1 came in as the geologists predicted. The model was not implemented in subsequent simulation work. To date, reservoir models used for flow simulation work have relied predominately on Gaussian distributed properties (porosity and permeability) and have employed a single injection well. Potosi Model 2013b incorporated the new VW2 logs, and exhibited an extra level of sophistication by delineating the vugular intervals. This method added further realism that likely represents the best reservoir approximation to date. Where the 2010 reservoir models were 10 by 10 mi (16 by 16 km) in area, the 2013 models were expanded in size to 30 by 30 mi (48 by 48 km). The latest reservoir simulations show that a minimum of four injectors might be required to meet target injection rates. Still, there is data that requires further scrutiny and modeling methodologies that require testing for the Potosi Formation. This work is currently ongoing, and the next phase of the reservoir modeling intends to implement valuable data like porosity derived from seismic inversion, seismically derived geobodies, or a combination of both to further define vugular zones and the porosity distribution within the Potosi Formation. Understanding the dual porosity, dual permeability character of the Potosi remains the greatest challenge in representing this formation. Further analysis of the FMI* fullbore formation microimager data may aid in assessing this uncertainty. The Potosi Formation is indeed an interesting formation, and recommendations to further characterize it are included in the following list


    Energy Technology Data Exchange (ETDEWEB)

    Michael L. Wiggins; Raymon L. Brown; Faruk Civan; Richard G. Hughes


    For many years, geoscientists and engineers have undertaken research to characterize naturally fractured reservoirs. Geoscientists have focused on understanding the process of fracturing and the subsequent measurement and description of fracture characteristics. Engineers have concentrated on the fluid flow behavior in the fracture-porous media system and the development of models to predict the hydrocarbon production from these complex systems. This research attempts to integrate these two complementary views to develop a quantitative reservoir characterization methodology and flow performance model for naturally fractured reservoirs. The research has focused on estimating naturally fractured reservoir properties from seismic data, predicting fracture characteristics from well logs, and developing a naturally fractured reservoir simulator. It is important to develop techniques that can be applied to estimate the important parameters in predicting the performance of naturally fractured reservoirs. This project proposes a method to relate seismic properties to the elastic compliance and permeability of the reservoir based upon a sugar cube model. In addition, methods are presented to use conventional well logs to estimate localized fracture information for reservoir characterization purposes. The ability to estimate fracture information from conventional well logs is very important in older wells where data are often limited. Finally, a desktop naturally fractured reservoir simulator has been developed for the purpose of predicting the performance of these complex reservoirs. The simulator incorporates vertical and horizontal wellbore models, methods to handle matrix to fracture fluid transfer, and fracture permeability tensors. This research project has developed methods to characterize and study the performance of naturally fractured reservoirs that integrate geoscience and engineering data. This is an important step in developing exploitation strategies for

  3. unconventional natural gas reservoirs

    International Nuclear Information System (INIS)

    Correa G, Tomas F; Osorio, Nelson; Restrepo R, Dora P


    This work is an exploration about different unconventional gas reservoirs worldwide: coal bed methane, tight gas, shale gas and gas hydrate? describing aspects such as definition, reserves, production methods, environmental issues and economics. The overview also mentioned preliminary studies about these sources in Colombia.

  4. Parallel reservoir simulator computations

    International Nuclear Information System (INIS)

    Hemanth-Kumar, K.; Young, L.C.


    The adaptation of a reservoir simulator for parallel computations is described. The simulator was originally designed for vector processors. It performs approximately 99% of its calculations in vector/parallel mode and relative to scalar calculations it achieves speedups of 65 and 81 for black oil and EOS simulations, respectively on the CRAY C-90

  5. Improved characterization of reservoir behavior by integration of reservoir performances data and rock type distributions

    Energy Technology Data Exchange (ETDEWEB)

    Davies, D.K.; Vessell, R.K. [David K. Davies & Associates, Kingwood, TX (United States); Doublet, L.E. [Texas A& M Univ., College Station, TX (United States)] [and others


    An integrated geological/petrophysical and reservoir engineering study was performed for a large, mature waterflood project (>250 wells, {approximately}80% water cut) at the North Robertson (Clear Fork) Unit, Gaines County, Texas. The primary goal of the study was to develop an integrated reservoir description for {open_quotes}targeted{close_quotes} (economic) 10-acre (4-hectare) infill drilling and future recovery operations in a low permeability, carbonate (dolomite) reservoir. Integration of the results from geological/petrophysical studies and reservoir performance analyses provide a rapid and effective method for developing a comprehensive reservoir description. This reservoir description can be used for reservoir flow simulation, performance prediction, infill targeting, waterflood management, and for optimizing well developments (patterns, completions, and stimulations). The following analyses were performed as part of this study: (1) Geological/petrophysical analyses: (core and well log data) - {open_quotes}Rock typing{close_quotes} based on qualitative and quantitative visualization of pore-scale features. Reservoir layering based on {open_quotes}rock typing {close_quotes} and hydraulic flow units. Development of a {open_quotes}core-log{close_quotes} model to estimate permeability using porosity and other properties derived from well logs. The core-log model is based on {open_quotes}rock types.{close_quotes} (2) Engineering analyses: (production and injection history, well tests) Material balance decline type curve analyses to estimate total reservoir volume, formation flow characteristics (flow capacity, skin factor, and fracture half-length), and indications of well/boundary interference. Estimated ultimate recovery analyses to yield movable oil (or injectable water) volumes, as well as indications of well and boundary interference.

  6. Modelling of local carbon deposition on rough test limiter exposed to the edge plasma of TEXTOR

    International Nuclear Information System (INIS)

    Dai Shuyu; Sun Jizhong; Wang Dezhen; Kirschner, A.; Matveev, D.; Borodin, D.; Bjoerkas, C.


    A Monte-Carlo code called SURO has been developed to study the influence of surface roughness on the impurity deposition characteristic in fusion experiments. SURO uses the test particle approach to describe the impact of background plasma and the deposition of impurity particles on a sinusoidal surface. The local impact angle and dynamic change of surface roughness as well as surface concentrations of different species due to erosion and deposition are taken into account. Coupled with 3D Monte-Carlo code ERO, SURO was used to study the impact of surface roughness on 13 C deposition in 13 CH 4 injection experiments in TEXTOR. The simulations showed that the amount of net deposited 13 C species increases with surface roughness. Parameter studies with varying 12 C and 13 C fluxes were performed to gain insight into impurity deposition characteristic on the rough surface. Calculations of the exposure time needed for surface smoothing for TEXTOR and ITER were also carried out for different scenarios. (author)

  7. Model based management of a reservoir system

    Energy Technology Data Exchange (ETDEWEB)

    Scharaw, B.; Westerhoff, T. [Fraunhofer IITB, Ilmenau (Germany). Anwendungszentrum Systemtechnik; Puta, H.; Wernstedt, J. [Technische Univ. Ilmenau (Germany)


    The main goals of reservoir management systems consist of prevention against flood water damages, the catchment of raw water and keeping all of the quality parameters within their limits besides controlling the water flows. In consideration of these goals a system model of the complete reservoir system Ohra-Schmalwasser-Tambach Dietharz was developed. This model has been used to develop optimized strategies for minimization of raw water production cost, for maximization of electrical energy production and to cover flood situations, as well. Therefore a proper forecast of the inflow to the reservoir from the catchment areas (especially flooding rivers) and the biological processes in the reservoir is important. The forecast model for the inflow to the reservoir is based on the catchment area model of Lorent and Gevers. It uses area precipitation, water supply from the snow cover, evapotranspiration and soil wetness data to calculate the amount of flow in rivers. The other aim of the project is to ensure the raw water quality using quality models, as well. Then a quality driven raw water supply will be possible. (orig.)

  8. Hydrocarbon Reservoir Parameter Estimation Using Production Data and Time-Lapse Seismic

    NARCIS (Netherlands)

    Przybysz-Jarnut, J.K.


    The numerical simulation of hydrocarbon reservoir flow is necessarily an approximation of the flow in the real reservoir. The knowledge about the reservoir is limited and some of the processes occurring are either not taken into account or not described in an adequate way. The parameters influencing

  9. Reservoir and injection technology and Heat Extraction Project

    Energy Technology Data Exchange (ETDEWEB)

    Horne, R.N.; Ramey, H.H. Jr.; Miller, F.G.; Brigham, W.E.; Kruger, P.


    For the Stanford Geothermal Program in the fiscal year 1989, the task areas include predictive modeling of reservoir behavior and tracer test interpretation and testing. Major emphasis is in reservoir technology, reinjection technology, and heat extraction. Predictive modeling of reservoir behavior consists of a multi-pronged approach to well test analysis under a variety of conditions. The efforts have been directed to designing and analyzing well tests in (1) naturally fractured reservoirs; (2) fractured wells; (3) complex reservoir geometries; and, (4) gas reservoirs including inertial and other effects. The analytical solutions for naturally fractured reservoirs are determined using fracture size distribution. In the study of fractured wells, an elliptical coordinate system is used to obtain semi-analytical solutions to finite conductivity fractures. Effort has also been directed to the modeling and creation of a user friendly computer program for steam/gas reservoirs including wellbore storage, skin and non-Darcy flow effects. This work has a complementary effort on modeling high flow rate wells including inertial effects in the wellbore and fractures. In addition, work on gravity drainage systems is being continued.

  10. SAMBA HIV semiquantitative test, a new point-of-care viral-load-monitoring assay for resource-limited settings. (United States)

    Ritchie, Allyson V; Ushiro-Lumb, Ines; Edemaga, Daniel; Joshi, Hrishikesh A; De Ruiter, Annemiek; Szumilin, Elisabeth; Jendrulek, Isabelle; McGuire, Megan; Goel, Neha; Sharma, Pia I; Allain, Jean-Pierre; Lee, Helen H


    Routine viral-load (VL) testing of HIV-infected individuals on antiretroviral therapy (ART) is used to monitor treatment efficacy. However, due to logistical challenges, implementation of VL has been difficult in resource-limited settings. The aim of this study was to evaluate the performance of the SAMBA semi-Q (simple amplification-based assay semiquantitative test for HIV-1) in London, Malawi, and Uganda. The SAMBA semi-Q can distinguish between patients with VLs above and below 1,000 copies/ml. The SAMBA semi-Q was validated with diluted clinical samples and blinded plasma samples collected from HIV-1-positive individuals. SAMBA semi-Q results were compared with results from the Roche COBAS AmpliPrep/COBAS TaqMan HIV-1 test, v2.0. Testing of 96 2- to 10-fold dilutions of four samples containing HIV-1 subtype C as well as 488 samples from patients in the United Kingdom, Malawi, and Uganda yielded an overall accuracy for the SAMBA semi-Q of 99% (95% confidence interval [CI], 93.8 to 99.9%) and 96.9% (95% CI 94.9 to 98.3%), respectively, compared to to the Roche test. Analysis of VL data from patients in Malawi and Uganda showed that the SAMBA cutoff of 1,000 copies/ml appropriately distinguished treated from untreated individuals. Furthermore, analysis of the viral loads of 232 patients on ART in Malawi and Uganda revealed similar patterns for virological control, defined as either SAMBA cutoff) or SAMBA semi-Q has adequate concurrency with the gold standard measurements for viral load. This test can allow VL monitoring of patients on ART at the point of care in resource-limited settings. Copyright © 2014 Ritchie et al.

  11. Analysis of Limit Cycle Oscillation Data from the Aeroelastic Test of the SUGAR Truss-Braced Wing Model (United States)

    Bartels, Robert E.; Funk, Christie; Scott, Robert C.


    Research focus in recent years has been given to the design of aircraft that provide significant reductions in emissions, noise and fuel usage. Increases in fuel efficiency have also generally been attended by overall increased wing flexibility. The truss-braced wing (TBW) configuration has been forwarded as one that increases fuel efficiency. The Boeing company recently tested the Subsonic Ultra Green Aircraft Research (SUGAR) Truss-Braced Wing (TBW) wind-tunnel model in the NASA Langley Research Center Transonic Dynamics Tunnel (TDT). This test resulted in a wealth of accelerometer data. Other publications have presented details of the construction of that model, the test itself, and a few of the results of the test. This paper aims to provide a much more detailed look at what the accelerometer data says about the onset of aeroelastic instability, usually known as flutter onset. Every flight vehicle has a location in the flight envelope of flutter onset, and the TBW vehicle is not different. For the TBW model test, the flutter onset generally occurred at the conditions that the Boeing company analysis said it should. What was not known until the test is that, over a large area of the Mach number dynamic pressure map, the model displayed wing/engine nacelle aeroelastic limit cycle oscillation (LCO). This paper dissects that LCO data in order to provide additional insights into the aeroelastic behavior of the model.

  12. Fourteenth workshop geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, H.J. Jr.; Kruger, P.; Horne, R.N.; Miller, F.G.; Brigham, W.E.; Cook, J.W.


    The Fourteenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 24--26, 1989. Major areas of discussion include: (1) well testing; (2) various field results; (3) geoscience; (4) geochemistry; (5) reinjection; (6) hot dry rock; and (7) numerical modelling. For these workshop proceedings, individual papers are processed separately for the Energy Data Base.

  13. Fourteenth workshop geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, H.J. Jr.; Kruger, P.; Horne, R.N.; Miller, F.G.; Brigham, W.E.; Cook, J.W.


    The Fourteenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 24--26, 1989. Major areas of discussion include: (1) well testing; (2) various field results; (3) geoscience; (4) geochemistry; (5) reinjection; (6) hot dry rock; and (7) numerical modelling. For these workshop proceedings, individual papers are processed separately for the Energy Data Base.

  14. Fifteenth workshop on geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)


    The Fifteenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 23--25, 1990. Major topics included: DOE's geothermal research and development program, well testing, field studies, geosciences, geysers, reinjection, tracers, geochemistry, and modeling.

  15. Development of an in-plane biaxial test for forming limit curve (FLC) characterization of metallic sheets

    International Nuclear Information System (INIS)

    Zidane, I; Guines, D; Léotoing, L; Ragneau, E


    The main objective of this work is to propose a new experimental device able to give for a single specimen a good prediction of rheological parameters and formability under static and dynamic conditions (for intermediate strain rates). In this paper, we focus on the characterization of sheet metal forming. The proposed device is a servo-hydraulic testing machine provided with four independent dynamic actuators allowing biaxial tensile tests on cruciform specimens. The formability is evaluated thanks to the classical forming limit diagram (FLD), and one of the difficulties of this study was the design of a dedicated specimen for which the necking phenomenon appears in its central zone. If necking is located in the central zone of the specimen, then the speed ratio between the two axes controls the strain path in this zone and a whole forming limit curve can be covered. Such a specimen is proposed through a numerical and experimental validation procedure. A rigorous procedure for the detection of numerical and experimental forming strains is also presented. Finally, an experimental forming limit curve is determined and validated for an aluminium alloy dedicated to the sheet forming processes (AA5086)

  16. Use and limitations of malaria rapid diagnostic testing by community health workers in war-torn Democratic Republic of Congo

    Directory of Open Access Journals (Sweden)

    Katsuva Jean


    Full Text Available Abstract Background Accurate and practical malaria diagnostics, such as immunochromatographic rapid diagnostic tests (RDTs, have the potential to avert unnecessary treatments and save lives. Volunteer community health workers (CHWs represent a potentially valuable human resource for expanding this technology to where it is most needed, remote rural communities in sub-Saharan Africa with limited health facilities and personnel. This study reports on a training programme for CHWs to incorporate RDTs into their management strategy for febrile children in the Democratic Republic of Congo, a tropical African setting ravaged by human conflict. Methods Prospective cohort study, satisfaction questionnaire and decision analysis. Results Twelve CHWs were trained to safely and accurately perform and interpret RDTs, then successfully implemented rapid diagnostic testing in their remote community in a cohort of 357 febrile children. CHWs were uniformly positive in evaluating RDTs for their utility and ease of use. However, high malaria prevalence in this cohort (93% by RDTs, 88% by light microscopy limited the cost-effectiveness of RDTs compared to presumptive treatment of all febrile children, as evidenced by findings from a simplified decision analysis. Conclusions CHWs can safely and effectively use RDTs in their management of febrile children; however, cost-effectiveness of RDTs is limited in zones of high malaria prevalence.

  17. Use and limitations of malaria rapid diagnostic testing by community health workers in war-torn Democratic Republic of Congo. (United States)

    Hawkes, Michael; Katsuva, Jean Paul; Masumbuko, Claude K


    Accurate and practical malaria diagnostics, such as immunochromatographic rapid diagnostic tests (RDTs), have the potential to avert unnecessary treatments and save lives. Volunteer community health workers (CHWs) represent a potentially valuable human resource for expanding this technology to where it is most needed, remote rural communities in sub-Saharan Africa with limited health facilities and personnel. This study reports on a training programme for CHWs to incorporate RDTs into their management strategy for febrile children in the Democratic Republic of Congo, a tropical African setting ravaged by human conflict. Prospective cohort study, satisfaction questionnaire and decision analysis. Twelve CHWs were trained to safely and accurately perform and interpret RDTs, then successfully implemented rapid diagnostic testing in their remote community in a cohort of 357 febrile children. CHWs were uniformly positive in evaluating RDTs for their utility and ease of use. However, high malaria prevalence in this cohort (93% by RDTs, 88% by light microscopy) limited the cost-effectiveness of RDTs compared to presumptive treatment of all febrile children, as evidenced by findings from a simplified decision analysis. CHWs can safely and effectively use RDTs in their management of febrile children; however, cost-effectiveness of RDTs is limited in zones of high malaria prevalence.

  18. Cognitive reserve in young and old healthy subjects: differences and similarities in a testing-the-limits paradigm with DSST.

    Directory of Open Access Journals (Sweden)

    Josef Zihl

    Full Text Available Cognitive reserve (CR is understood as capacity to cope with challenging conditions, e.g. after brain injury or in states of brain dysfunction, or age-related cognitive decline. CR in elderly subjects has attracted much research interest, but differences between healthy older and younger subjects have not been addressed in detail hitherto. Usually, one-time standard individual assessments are used to characterise CR. Here we observe CR as individual improvement in cognitive performance (gain in a complex testing-the-limits paradigm, the digit symbol substitution test (DSST, with 10 repeated measurements, in 140 younger (20-30 yrs and 140 older (57-74 yrs healthy subjects. In addition, we assessed attention, memory and executive function, and mood and personality traits as potential influence factors for CR. We found that both, younger and older subjects showed significant gains, which were significantly correlated with speed of information processing, verbal short-term memory and visual problem solving in the older group only. Gender, personality traits and mood did not significantly influence gains in either group. Surprisingly about half of the older subjects performed at the level of the younger group, suggesting that interindividual differences in CR are possibly age-independent. We propose that these findings may also be understood as indication that one-time standard individual measurements do not allow assessment of CR, and that the use of DSST in a testing-the-limits paradigm is a valuable assessment method for CR in young and elderly subjects.

  19. New experimental limits on heavy neutrino mixing in 8B decay obtained with the BOREXINO counting test facility

    International Nuclear Information System (INIS)

    Back, H.O.; Hagner, C.; Vogelaar, R.B.


    If heavy neutrinos with mass m νH ≥2m e are emitted in the decays of 8 B in the Sun, then decays ν H →ν L +e + +e - should be observed. The results of background measurements with the BOREXINO Counting Test Facility have been used to obtain bounds on the number of these decays. As a result, new limits on the coupling |U eH | 2 of a massive neutrino in the range of 1.1 to 12 MeV have been derived (|U eH | 2 ≤10 -3 -10 -5 ). The obtained limits on the mixing parameter are stronger than those obtained in the previous experiments using nuclear reactors and accelerators

  20. The use of Minilabs to improve the testing capacity of regulatory authorities in resource limited settings: Tanzanian experience. (United States)

    Risha, Peter Gasper; Msuya, Zera; Clark, Malcolm; Johnson, Keith; Ndomondo-Sigonda, Margareth; Layloff, Thomas


    The Tanzania Food and Drugs Authority piloted the use of Minilab kits, a thin-layer-chromatographic based drug quality testing technique, in a two-tier quality assurance program. The program is intended to improve testing capacity with timely screening of the quality of medicines as they enter the market. After 1 week training of inspectors on Minilab screening techniques, they were stationed at key Ports-of-Entry (POE) to screen the quality of imported medicines. In addition, three non-Ports-of-Entry centres were established to screen samples collected during Post-Marketing-Surveillance. Standard operating procedures (SOPs) were developed to structure and standardize the implementation process. Over 1200 samples were tested using the Minilab outside the central quality control laboratory (QCL), almost doubling the previous testing capacity. The program contributed to increased regulatory reach and visibility of the Authority throughout the country, serving as a deterrent against entry of substandard medicines into market. The use of Minilab for quality screening was inexpensive and provided a high sample throughput. However, it suffers from the limitation that it can reliably detect only grossly substandard or wrong drug samples and therefore, it should not be used as an independent testing resource but in conjunction with a full-service quality control laboratory capable of auditing reported substandard results.

  1. Can exposure limitations for well-known contact allergens be simplified? An analysis of dose-response patch test data. (United States)

    Fischer, Louise Arup; Menné, Torkil; Voelund, Aage; Johansen, Jeanne Duus


    Allergic contact dermatitis is triggered by chemicals in the environment. Primary prevention is aimed at minimizing the risk of induction, whereas secondary and tertiary prevention are aimed at reducing elicitation. To identify the elicitation doses that will elicit an allergic reaction in 10% of allergic individuals under patch test conditions (ED(10) patch test) for different allergens, and to compare the results with those for different allergens and with animal data indicating sensitizing potency from the literature. The literature was searched for patch test elicitation studies that fulfilled six selected criteria. The elicitation doses were calculated, and fitted dose-response curves were drawn. Sixteen studies with eight different allergens-methylchloroisothiazolinone/ methylisothiazolinone, formaldehyde, nickel, cobalt, chromium, isoeugenol, hydroxyiso hexyl 3-cyclohexene carboxaldehyde, and methyldibromo glutaronitrile-were selected. The median ED(10) value was 0.835 µg/cm(2). The ED(10) patch test values were all within a factor of 7 from the lowest to the highest value, leaving out three outliers. No obvious patterns between the sensitization and elicitation doses for the allergens were found. We found a rather small variation in the ED(10) patch test between the allergens, and no clear relationship between induction potency and elicitation threshold of a range of allergens. This knowledge may stimulate thoughts on introducing a generic approach for limitations in exposure to well-known allergens. © 2011 John Wiley & Sons A/S.

  2. Work reservoirs in thermodynamics (United States)

    Anacleto, Joaquim


    We stress the usefulness of the work reservoir in the formalism of thermodynamics, in particular in the context of the first law. To elucidate its usefulness, the formalism is then applied to the Joule expansion and other peculiar and instructive experimental situations, clarifying the concepts of configuration and dissipative work. The ideas and discussions presented in this study are primarily intended for undergraduate students, but they might also be useful to graduate students, researchers and teachers.

  3. Test Characteristics of Emergency Physician-Performed Limited Compression Ultrasound for Lower-Extremity Deep Vein Thrombosis. (United States)

    Kim, Daniel J; Byyny, Richard L; Rice, Cliff A; Faragher, Jeff P; Nordenholz, Kristen E; Haukoos, Jason S; Liao, Michael M; Kendall, John L


    The current literature suggests that emergency physician (EP)-performed limited compression ultrasound (LCUS) is a rapid and accurate test for deep vein thrombosis (DVT). Our primary objective was to determine the sensitivity and specificity of LCUS for the diagnosis of DVT when performed by a large heterogeneous group of EPs. This was a prospective diagnostic test assessment of LCUS conducted at two urban academic emergency departments. The scanning protocol involved compression at the common femoral, superficial femoral, and popliteal veins. Patients were eligible if undergoing radiology department ultrasound of the lower extremity with moderate or high pretest probability for DVT, or low pretest probability for DVT with a positive d-dimer. The enrolling EP performed LCUS before radiology department ultrasound of the same lower extremity. Sensitivity, specificity, and associated 95% confidence intervals (CIs) were calculated with the radiologist interpretation of the radiology department ultrasound as the criterion standard. A total of 56 EPs enrolled 296 patients for LCUS, with a median age of 50 years and 50% female. Fifty (17%) DVTs were identified by radiology department ultrasound, and another five (2%) cases were deemed indeterminate. The sensitivity and specificity of EP-performed LCUS was 86% (95% CI 73-94%) and 93% (95% CI 89-96%), respectively. A large heterogeneous group of EPs with limited training can perform LCUS with intermediate diagnostic accuracy. Unfortunately, LCUS performed by EPs with limited ultrasound training is not sufficiently sensitive or specific to rule out or diagnose DVT as a single testing modality. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Paratuberculosis vaccination causes only limited cross-reactivity in the skin test for diagnosis of bovine tuberculosis.

    Directory of Open Access Journals (Sweden)

    Joseba M Garrido

    Full Text Available Although there is a wide consensus on the efficacy of paratuberculosis vaccination to limit economic losses, its use has been restricted because of its interference in the diagnosis of tuberculosis. Data from a vaccine clinical trial in the Basque Country (Spain has been evaluated in relationship with bovine tuberculosis intradermal test results. The trial included two herds applying a Test and Culling strategy and five applying an inactivated vaccine. The vaccine was applied to animals of all ages present in each vaccinated herd when joining the trial, and then to all the replacers within their first three months of life. Yearly testing done with the comparative intradermal test (CIT was applied to all animals older than 6 weeks. Between 2005 and 2011, the study generated 2,033 records from Vaccinated Herds (VH and 2,252 from Test and Cull herds (TC. Pre-vaccination positive results rate was 2.40% among the 7 herds in the single bovine intradermal tuberculin test (BSIT. Two years later it rose to 20.42% in the VH and remained below at 0.75% in the TC. Applying the CIT reduced these rates to only 0.58% in the VH and to 0.25% in the TC ons. Regarding time since each animal joined the program, the proportion of positives to BSIT was variable and, in some cases, significantly different between time points. With regard to the age of vaccination, no significant differences were found between vaccination within the first year of life and afterwards. Vaccinated animals showed seventeen times more reactions than the non-vaccinated in the BSIT, but only four times more in the CIT. In conclusion, comparative intradermal test can be a useful tool to differentiate paratuberculosis vaccine cross-reactions from specific bovine tuberculosis reactions according to the European and Spanish legislation.

  5. Paratuberculosis Vaccination Causes Only Limited Cross-Reactivity in the Skin Test for Diagnosis of Bovine Tuberculosis (United States)

    Garrido, Joseba M.; Vazquez, Patricia; Molina, Elena; Plazaola, Jose M.; Sevilla, Iker A.; Geijo, Maria V.; Alonso-Hearn, Marta; Juste, Ramon A.


    Although there is a wide consensus on the efficacy of paratuberculosis vaccination to limit economic losses, its use has been restricted because of its interference in the diagnosis of tuberculosis. Data from a vaccine clinical trial in the Basque Country (Spain) has been evaluated in relationship with bovine tuberculosis intradermal test results. The trial included two herds applying a Test and Culling strategy and five applying an inactivated vaccine. The vaccine was applied to animals of all ages present in each vaccinated herd when joining the trial, and then to all the replacers within their first three months of life. Yearly testing done with the comparative intradermal test (CIT) was applied to all animals older than 6 weeks. Between 2005 and 2011, the study generated 2,033 records from Vaccinated Herds (VH) and 2,252 from Test and Cull herds (TC). Pre-vaccination positive results rate was 2.40% among the 7 herds in the single bovine intradermal tuberculin test (BSIT). Two years later it rose to 20.42% in the VH and remained below at 0.75% in the TC. Applying the CIT reduced these rates to only 0.58% in the VH and to 0.25% in the TC ons. Regarding time since each animal joined the program, the proportion of positives to BSIT was variable and, in some cases, significantly different between time points. With regard to the age of vaccination, no significant differences were found between vaccination within the first year of life and afterwards. Vaccinated animals showed seventeen times more reactions than the non-vaccinated in the BSIT, but only four times more in the CIT. In conclusion, comparative intradermal test can be a useful tool to differentiate paratuberculosis vaccine cross-reactions from specific bovine tuberculosis reactions according to the European and Spanish legislation. PMID:24303029

  6. A direct test of nitrogen and phosphorus limitation to net primary productivity in a lowland tropical wet forest. (United States)

    Alvarez-Clare, S; Mack, M C; Brooks, M


    Experimental evidence for limitation of net primary productivity (NPP) by nitrogen (N) or phosphorus (P) in lowland tropical forests is rare, and the results from the few existing studies have been inconclusive. To directly test if N or P limit NPP in a lowland tropical wet forest in Costa Rica, we conducted a full factorial fertilization experiment (4 treatments x 6 replicates in 30 x 30 m plots). We focused on the influence of tree size and taxa on nutrient limitation, because in these forests a wide variety of tree functional traits related to nutrient acquisition and use are likely to regulate biogeochemical processes. After 2.7 years, a higher percentage of trees per plot increased basal area (BA) with P additions (66.45% +/- 3.28% without P vs. 76.88% +/- 3.28% with P), but there were no other community-level responses to N or P additions on BA increase, litterfall productivity, or root growth. Phosphorus additions resulted in doubled stem growth rates in small trees (5-10 cm diameter at breast height (dbh); [P 30 cm dbh). Phosphorus additions also increased the percentage of seedling survival from 59% to 78% (P importance of considering different aspects of the plant community when making predictions concerning nutrient limitation. We postulate that in diverse, lowland tropical forests "heterogeneous nutrient limitation" occurs, not only driven by variability in nutrient responses among taxa, but also among size classes and potential functional groups. Heterogeneous responses to nutrient additions could lead to changes in forest structure or even diversity in the long-term, affecting rates of NPP and thus carbon cycling.

  7. A reservoir morphology database for the conterminous United States (United States)

    Rodgers, Kirk D.


    The U.S. Geological Survey, in cooperation with the Reservoir Fisheries Habitat Partnership, combined multiple national databases to create one comprehensive national reservoir database and to calculate new morphological metrics for 3,828 reservoirs. These new metrics include, but are not limited to, shoreline development index, index of basin permanence, development of volume, and other descriptive metrics based on established morphometric formulas. The new database also contains modeled chemical and physical metrics. Because of the nature of the existing databases used to compile the Reservoir Morphology Database and the inherent missing data, some metrics were not populated. One comprehensive database will assist water-resource managers in their understanding of local reservoir morphology and water chemistry characteristics throughout the continental United States.

  8. Advantageous Reservoir Characterization Technology in Extra Low Permeability Oil Reservoirs

    Directory of Open Access Journals (Sweden)

    Yutian Luo


    Full Text Available This paper took extra low permeability reservoirs in Dagang Liujianfang Oilfield as an example and analyzed different types of microscopic pore structures by SEM, casting thin sections fluorescence microscope, and so on. With adoption of rate-controlled mercury penetration, NMR, and some other advanced techniques, based on evaluation parameters, namely, throat radius, volume percentage of mobile fluid, start-up pressure gradient, and clay content, the classification and assessment method of extra low permeability reservoirs was improved and the parameter boundaries of the advantageous reservoirs were established. The physical properties of reservoirs with different depth are different. Clay mineral variation range is 7.0%, and throat radius variation range is 1.81 μm, and start pressure gradient range is 0.23 MPa/m, and movable fluid percentage change range is 17.4%. The class IV reservoirs account for 9.56%, class II reservoirs account for 12.16%, and class III reservoirs account for 78.29%. According to the comparison of different development methods, class II reservoir is most suitable for waterflooding development, and class IV reservoir is most suitable for gas injection development. Taking into account the gas injection in the upper section of the reservoir, the next section of water injection development will achieve the best results.

  9. Application of integrated reservoir management and reservoir characterization to optimize infill drilling. Annual report, June 13, 1994--June 12, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Pande, P.K.


    This project has used a multi-disciplinary approach employing geology, geophysics, and engineering to conduct advanced reservoir characterization and management activities to design and implement an optimized infill drilling program at the North Robertson (Clearfork) Unit in Gaines County, Texas. The activities during the first Budget Period have consisted of developing an integrated reservoir description from geological, engineering, and geostatistical studies, and using this description for reservoir flow simulation. Specific reservoir management activities are being identified and tested. The geologically targeted infill drilling program will be implemented using the results of this work. A significant contribution of this project is to demonstrate the use of cost-effective reservoir characterization and management tools that will be helpful to both independent and major operators for the optimal development of heterogeneous, low permeability shallow-shelf carbonate (SSC) reservoirs. The techniques that are outlined for the formulation of an integrated reservoir description apply to all oil and gas reservoirs, but are specifically tailored for use in the heterogeneous, low permeability carbonate reservoirs of West Texas.

  10. EOS simulation and GRNN modeling of the constant volume depletion behavior of gas condensate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Elsharkawy, A.M.; Foda, S.G. [Kuwait University, Safat (Kuwait). Petroleum Engineering Dept.


    Currently, two approaches are being used to predict the changes in retrograde gas condensate composition and estimate the pressure depletion behavior of gas condensate reservoirs. The first approach uses the equation of states whereas the second uses empirical correlations. Equations of states (EOS) are poor predictive tools for complex hydrocarbon systems. The EOS needs adjustment against phase behavior data of reservoir fluid of known composition. The empirical correlation does not involve numerous numerical computations but their accuracy is limited. This study presents two general regression neural network (GRNN) models. The first model, GRNNM1, is developed to predict dew point pressure and gas compressibility at dew point using initial composition of numerous samples while the second model, GRNNM2, is developed to predict the changes in well stream effluent composition at any stages of pressure depletion. GRNNM2 can also be used to determine the initial reservoir fluid composition using dew point pressure, gas compressibility at dew point, and reservoir temperature. These models are based on analysis of 142 sample of laboratory studies of constant volume depletion (CVD) for gas condensate systems forming a total of 1082 depletion stages. The database represents a wide range of gas condensate systems obtained worldwide. The performance of the GRNN models has been compared to simulation results of the equation of state. The study shows that the proposed general regression neural network models are accurate, valid, and reliable. These models can be used to forecast CVD data needed for many reservoir engineering calculations in case laboratory data is unavailable. The GRNN models save computer time involved in EOS calculations. The study also show that once these models are properly trained they can be used to cut expenses of frequent sampling and laborious experimental CVD tests required for gas condensate reservoirs. 55 refs., 13 figs., 6 tabs.

  11. In-situ Tritium Measurements of the Tokamak Fusion Test Reactor Bumper Limiter Tiles Post D-T Operations

    International Nuclear Information System (INIS)

    C.A. Gentile; C.H. Skinner; K.M. Young; M. Nishi; S. Langish; et al


    The Princeton Plasma Physics Laboratory (PPPL) Engineering and Research Staff in collaboration with members of the Japan Atomic Energy Research Institute (JAERI), Tritium Engineering Laboratory have commenced in-situ tritium measurements of the TFTR bumper limiter. The Tokamak Fusion Test Reactor (TFTR) operated with tritium from 1993 to 1997. During this time ∼ 53,000 Ci of tritium was injected into the TFTR vacuum vessel. After the cessation of TFTR plasma operations in April 1997 an aggressive tritium cleanup campaign lasting ∼ 3 months was initiated. The TFTR vacuum vessel was subjected to a regimen of glow discharge cleaning (GDC) and dry nitrogen and ''moist air'' purges. Currently ∼ 7,500 Ci of tritium remains in the vacuum vessel largely contained in the limiter tiles. The TFTR limiter is composed of 1,920 carbon tiles with an average weight of ∼ 600 grams each. The location and distribution of tritium on the TFTR carbon tiles are of considerable interest. Future magnetically confined fusion devices employing carbon as a limiter material may be considerably constrained due to potentially large tritium inventories being tenaciously held on the surface of the tiles. In-situ tritium measurements were conducted in TFTR bay L during August and November 1998. During the bay L measurement campaign open wall ion chambers and ultra thin thermoluminscent dosimeters (TLD) affixed to a boom and end effector were deployed into the vacuum vessel. The detectors were designed to make contact with the surface of the bumper limiter tile and to provide either real time (ion chamber) or passive (TLD) indication of the surface tritium concentration. The open wall ion chambers were positioned onto the surface of the tile in a manner which employed the surface of the tile as one of the walls of the chamber. The ion chambers, which are (electrically) gamma insensitive, were landed at four positions per tile. The geometry for landing the TLD's provided measurement at 24

  12. Seismic Evaluation of Hydrocarbon Saturation in Deep-Water Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Michael Batzle


    During this last period of the ''Seismic Evaluation of Hydrocarbon Saturation in Deep-Water Reservoirs'' project (Grant/Cooperative Agreement DE-FC26-02NT15342), we finalized integration of rock physics, well log analysis, seismic processing, and forward modeling techniques. Most of the last quarter was spent combining the results from the principal investigators and come to some final conclusions about the project. Also much of the effort was directed towards technology transfer through the Direct Hydrocarbon Indicators mini-symposium at UH and through publications. As a result we have: (1) Tested a new method to directly invert reservoir properties, water saturation, Sw, and porosity from seismic AVO attributes; (2) Constrained the seismic response based on fluid and rock property correlations; (3) Reprocessed seismic data from Ursa field; (4) Compared thin layer property distributions and averaging on AVO response; (5) Related pressures and sorting effects on porosity and their influence on DHI's; (6) Examined and compared gas saturation effects for deep and shallow reservoirs; (7) Performed forward modeling using geobodies from deepwater outcrops; (8) Documented velocities for deepwater sediments; (9) Continued incorporating outcrop descriptive models in seismic forward models; (10) Held an open DHI symposium to present the final results of the project; (11) Relations between Sw, porosity, and AVO attributes; (12) Models of Complex, Layered Reservoirs; and (14) Technology transfer Several factors can contribute to limit our ability to extract accurate hydrocarbon saturations in deep water environments. Rock and fluid properties are one factor, since, for example, hydrocarbon properties will be considerably different with great depths (high pressure) when compared to shallow properties. Significant over pressure, on the other hand will make the rocks behave as if they were shallower. In addition to the physical properties, the scale and

  13. The limited utility of screening laboratory tests and electrocardiograms in the management of unintentional asymptomatic pediatric ingestions. (United States)

    Wang, George Sam; Deakyne, Sara; Bajaj, Lalit; Yin, Shan; Heard, Kennon; Roosevelt, Genie


    Suspected ingestions are a common chief complaint to the emergency department although the majority of ingestions by children are insignificant. Assess the utility of screening laboratory tests and Electrocardiograms (ECGs) in unintentional asymptomatic pediatric poisonings. Retrospective chart review at a tertiary care children's hospital and a regional poison center of patients less than 12 years of age using ICD-9 codes from January 2005 through December 2008. Laboratory or ECG results requiring intervention and/or direct treatment, a non-RPC subspecialty consultation, and/or prolonged Emergency Department stay was considered changed management. Five hundred ninety five suspected ingestions met our criteria. The median age was 2.6 years (IQR 1.6, 3.0 years) and 56% were male. One laboratory test or ECG was obtained in 233 patients (39%). Of 24 screening ECGs, 32 complete blood counts and 34 blood gases, none were clinically significant. Fifty-two patients received screening metabolic panels, 3 were abnormal and 2 changed management (anion gap metabolic acidosis with unsuspected salicylate ingestions). None of the 127 (21%) screening acetaminophen levels changed management. Two of sixty-five (13%) screening salicylate levels changed management. Three screening urine toxicology tests on patients with altered mental status were positive without ingestion history. No patient under the age of 12 years with normal vital signs and normal mental status had positive screening tests. Screening laboratory tests and ECGs were of limited utility and rarely changed management despite being ordered in a significant number of patients. Screening tests are rarely indicated in unintentional overdoses in children who are asymptomatic. Copyright © 2013. Published by Elsevier Inc.

  14. Forming limit curves determined in high-speed Nakajima tests and predicted by a strain rate sensitive model (United States)

    Weiß-Borkowski, Nathalie; Lian, Juhne; Marten, Thorsten; Tröster, Thomas; Münstermann, Sebastian; Bleck, Wolfgang


    Material characteristics such as yield strength and failure strain are affected by the loading speed. Even the start of instability and necking depends not only on the strain hardening coefficient but also on the strain rate sensitivity parameter. Therefore, the strain rate dependence of materials for both plasticity and the failure behavior is taken into account in crash simulations for strain rates up to 1,000 s-1. The current standard experiment for investigation of strain rate dependence is the high speed tensile test as described in a FAT guideline. Moreover, the need of material characterization at multi-axial loadings and high strain rates is pointed out in FAT guideline. Forming limit diagrams (FLD) can be used for the description of the material`s instability behavior at multi-axial loading. Usually, the FLD are determined quasi-statically at 1.5 mm/s. The usage of experimentally determined, quasi-static FLD also at high strain rates leads to great uncertainties and thus can be hardly used in crash simulations. A possibility for experimentally recording FLD at high forming rates > 100 s-1 offers the present described high speed Nakajima test. The results for the deep drawing steel DC01 illustrate the need of the determination of dynamic FLD. In this context, due to the strain rate dependence of the material behavior an extrapolation of quasi-static FLD is not feasible. Alternatively, the prediction of forming limit curves (FLC) at high strain rates is possible with the extended modified maximum force criterion. This new and extended model includes the strain rate dependence and therefore predicting forming limits at dynamic forming gets possible. The new approach is described and the accordance of experimental determined and predicted results for the begin of instability is presented.

  15. Integrating gravimetric and interferometric synthetic aperture radar data for enhancing reservoir history matching of carbonate gas and volatile oil reservoirs

    KAUST Repository

    Katterbauer, Klemens


    Reservoir history matching is assuming a critical role in understanding reservoir characteristics, tracking water fronts, and forecasting production. While production data have been incorporated for matching reservoir production levels and estimating critical reservoir parameters, the sparse spatial nature of this dataset limits the efficiency of the history matching process. Recently, gravimetry techniques have significantly advanced to the point of providing measurement accuracy in the microgal range and consequently can be used for the tracking of gas displacement caused by water influx. While gravity measurements provide information on subsurface density changes, i.e., the composition of the reservoir, these data do only yield marginal information about temporal displacements of oil and inflowing water. We propose to complement gravimetric data with interferometric synthetic aperture radar surface deformation data to exploit the strong pressure deformation relationship for enhancing fluid flow direction forecasts. We have developed an ensemble Kalman-filter-based history matching framework for gas, gas condensate, and volatile oil reservoirs, which synergizes time-lapse gravity and interferometric synthetic aperture radar data for improved reservoir management and reservoir forecasts. Based on a dual state-parameter estimation algorithm separating the estimation of static reservoir parameters from the dynamic reservoir parameters, our numerical experiments demonstrate that history matching gravity measurements allow monitoring the density changes caused by oil-gas phase transition and water influx to determine the saturation levels, whereas the interferometric synthetic aperture radar measurements help to improve the forecasts of hydrocarbon production and water displacement directions. The reservoir estimates resulting from the dual filtering scheme are on average 20%-40% better than those from the joint estimation scheme, but require about a 30% increase in

  16. Gasbuggy reservoir evaluation - 1969 report

    International Nuclear Information System (INIS)

    Atkinson, C.H.; Ward, Don C.; Lemon, R.F.


    The December 10, 1967, Project Gasbuggy nuclear detonation followed the drilling and testing of two exploratory wells which confirmed reservoir characteristics and suitability of the site. Reentry and gas production testing of the explosive emplacement hole indicated a collapse chimney about 150 feet in diameter extending from the 4,240-foot detonation depth to about 3,900 feet, the top of the 300-foot-thick Pictured Cliffs gas sand. Production tests of the chimney well in the summer of 1968 and during the last 12 months have resulted in a cumulative production of 213 million cubic feet of hydrocarbons, and gas recovery in 20 years is estimated to be 900 million cubic feet, which would be an increase by a factor of at least 5 over estimated recovery from conventional field wells in this low permeability area. At the end of production tests the flow rate was 160,000 cubic feet per day, which is 6 to 7 times that of an average field well in the area. Data from reentry of a pre-shot test well and a new postshot well at distances from the detonation of 300 and 250 feet, respectively, indicate low productivity and consequently low permeability in any fractures at these locations. (author)

  17. Solid-State Fault Current Limiter Development : Design and Testing Update of a 15kV SSCL Power Stack

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Ram Adapa; Mr. Dante Piccone


    ABSTRACT The Solid-State Fault Current Limiter (SSCL) is a promising technology that can be applied to utility power delivery systems to address the problem of increasing fault currents associated with load growth. As demand continues to grow, more power is added to utility system either by increasing generator capacity or by adding distributed generators, resulting in higher available fault currents, often beyond the capabilities of the present infrastructure. The SSCL is power-electronics based equipment designed to work with the present utility system to address this problem. The SSCL monitors the line current and dynamically inserts additional impedance into the line in the event of a fault being detected. The SSCL is based on a modular design and can be configured for 5kV through 69kV systems at nominal current ratings of 1000A to 4000A. Results and Findings This report provides the final test results on the development of 15kV class SSCL single phase power stack. The scope of work included the design of the modular standard building block sub-assemblies, the design and manufacture of the power stack and the testing of the power stack for the key functional tests of continuous current capability and fault current limiting action. Challenges and Objectives Solid-State Current Limiter technology impacts a wide spectrum of utility engineering and operating personnel. It addresses the problems associated with load growth both at Transmission and Distribution class networks. The design concept is pioneering in terms of developing the most efficient and compact power electronics equipment for utility use. The initial test results of the standard building blocks are promising. The independent laboratory tests of the power stack are promising. However the complete 3 phase system needs rigorous testing for performance and reliability. Applications, Values, and Use The SSCL is an intelligent power-electronics device which is modular in design and can provide current

  18. Limitations of widely used high-risk human papillomavirus laboratory-developed testing in cervical cancer screening

    Directory of Open Access Journals (Sweden)

    Naryshkin S


    Full Text Available Sonya Naryshkin,1 R Marshall Austin21Department of Pathology, Mercy Health System, Janesville, WI; 2Department of Pathology, Magee-Womens Hospital of University of Pittsburgh Medical Center, Pittsburgh, PA, USAObjective: To increase awareness of the limitations of high-risk human papillomavirus (hrHPV laboratory-developed testing (LDT widely used in US cervical cancer screening.Methods and results: A young woman in her 30s was diagnosed and treated for stage 1B1 cervical squamous cell carcinoma in which HPV 16 DNA was detected using polymerase chain reaction testing. Both 1 month before and 42 months before cervical cancer diagnosis, the patient had highly abnormal cytology findings; however, residual SurePath™ (Becton, Dickson and Company, Franklin Lakes, NJ vial fluid yielded negative Hybrid Capture 2 (HC2; Qiagen NV, Hilden, Germany hrHPV LDT results from each of the two specimens. This prompted questions to be asked concerning the performance characteristics of hrHPV LDT. A review of the available data indicates that (1 purification of DNA from SurePath specimens requires complex sample preparation due to formaldehyde crosslinking of proteins and nucleic acids, (2 HC2–SurePath hrHPV testing had not been Food and Drug Administration-approved after multiple premarket approval submissions, (3 detectible hrHPV DNA in the SurePath vial decreases over time, and (4 US laboratories performing HC2–SurePath hrHPV LDT testing are not using a standardized manufacturer-endorsed procedure.Conclusion: Recently updated cervical screening guidelines in the US recommend against the use of hrHPV LDT in cervical screening, including widely used HC2 testing from the SurePath vial. The manufacturer recently issued a technical bulletin specifically warning that use of SurePath samples with the HC2 hrHPV test may provide false negative results and potentially compromise patient safety. Co-collection using a Food and Drug Administration-approved hrHPV test

  19. Modelling of Reservoir Operations using Fuzzy Logic and ANNs (United States)

    Van De Giesen, N.; Coerver, B.; Rutten, M.


    Today, almost 40.000 large reservoirs, containing approximately 6.000 km3 of water and inundating an area of almost 400.000 km2, can be found on earth. Since these reservoirs have a storage capacity of almost one-sixth of the global annual river discharge they have a large impact on the timing, volume and peaks of river discharges. Global Hydrological Models (GHM) are thus significantly influenced by these anthropogenic changes in river flows. We developed a parametrically parsimonious method to extract operational rules based on historical reservoir storage and inflow time-series. Managing a reservoir is an imprecise and vague undertaking. Operators always face uncertainties about inflows, evaporation, seepage losses and various water demands to be met. They often base their decisions on experience and on available information, like reservoir storage and the previous periods inflow. We modeled this decision-making process through a combination of fuzzy logic and artificial neural networks in an Adaptive-Network-based Fuzzy Inference System (ANFIS). In a sensitivity analysis, we compared results for reservoirs in Vietnam, Central Asia and the USA. ANFIS can indeed capture reservoirs operations adequately when fed with a historical monthly time-series of inflows and storage. It was shown that using ANFIS, operational rules of existing reservoirs can be derived without much prior knowledge about the reservoirs. Their validity was tested by comparing actual and simulated releases with each other. For the eleven reservoirs modelled, the normalised outflow, , was predicted with a MSE of 0.002 to 0.044. The rules can be incorporated into GHMs. After a network for a specific reservoir has been trained, the inflow calculated by the hydrological model can be combined with the release and initial storage to calculate the storage for the next time-step using a mass balance. Subsequently, the release can be predicted one time-step ahead using the inflow and storage.

  20. Geothermal reservoir management

    Energy Technology Data Exchange (ETDEWEB)

    Scherer, C.R.; Golabi, K.


    The optimal management of a hot water geothermal reservoir was considered. The physical system investigated includes a three-dimensional aquifer from which hot water is pumped and circulated through a heat exchanger. Heat removed from the geothermal fluid is transferred to a building complex or other facility for space heating. After passing through the heat exchanger, the (now cooled) geothermal fluid is reinjected into the aquifer. This cools the reservoir at a rate predicted by an expression relating pumping rate, time, and production hole temperature. The economic model proposed in the study maximizes discounted value of energy transferred across the heat exchanger minus the discounted cost of wells, equipment, and pumping energy. The real value of energy is assumed to increase at r percent per year. A major decision variable is the production or pumping rate (which is constant over the project life). Other decision variables in this optimization are production timing, reinjection temperature, and the economic life of the reservoir at the selected pumping rate. Results show that waiting time to production and production life increases as r increases and decreases as the discount rate increases. Production rate decreases as r increases and increases as the discount rate increases. The optimal injection temperature is very close to the temperature of the steam produced on the other side of the heat exchanger, and is virtually independent of r and the discount rate. Sensitivity of the decision variables to geohydrological parameters was also investigated. Initial aquifer temperature and permeability have a major influence on these variables, although aquifer porosity is of less importance. A penalty was considered for production delay after the lease is granted.

  1. Use of a Rapid Test for Diagnosis of Dengue during Suspected Dengue Outbreaks in Resource-Limited Regions. (United States)

    Hunsperger, Elizabeth A; Sharp, Tyler M; Lalita, Paul; Tikomaidraubuta, Kini; Cardoso, Yolanda Rebello; Naivalu, Taina; Khan, Aalisha Sahu; Marfel, Maria; Hancock, W Thane; Tomashek, Kay M; Margolis, Harold S


    Dengue is major public health problem, globally. Timely verification of suspected dengue outbreaks allows for public health response, leading to the initiation of appropriate clinical care. Because the clinical presentation of dengue is nonspecific, dengue diagnosis would benefit from a sensitive rapid diagnostic test (RDT). We evaluated the diagnostic performance of an RDT that detects dengue virus (DENV) nonstructural protein 1 (NS1) and anti-DENV IgM during suspected acute febrile illness (AFI) outbreaks in four countries. Real-time reverse transcription-PCR and anti-DENV IgM enzyme-linked immunosorbent assay were used to verify RDT results. Anti-DENV IgM RDT sensitivity and specificity ranged from 55.3 to 91.7% and 85.3 to 98.5%, respectively, and NS1 sensitivity and specificity ranged from 49.7 to 92.9% and 22.2 to 89.0%, respectively. Sensitivity varied by timing of specimen collection and DENV serotype. Combined test results moderately improved the sensitivity. The use of RDTs identified dengue as the cause of AFI outbreaks where reference diagnostic testing was limited or unavailable. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  2. The Effect of Music on the Test Scores of the Students in Limits and Derivatives Subject in the Mathematics Exams Done with Music (United States)

    Kesan, Cenk; Ozkalkan, Zuhal; Iric, Hamdullah; Kaya, Deniz


    In the exams based on limits and derivatives, in this study, it was tried to determine that if there was any difference in students' test scores according to the type of music listened to and environment without music. For this purpose, the achievement test including limits and derivatives and whose reliability coefficient of Cronbach Alpha is…

  3. Advances in photonic reservoir computing (United States)

    Van der Sande, Guy; Brunner, Daniel; Soriano, Miguel C.


    We review a novel paradigm that has emerged in analogue neuromorphic optical computing. The goal is to implement a reservoir computer in optics, where information is encoded in the intensity and phase of the optical field. Reservoir computing is a bio-inspired approach especially suited for processing time-dependent information. The reservoir's complex and high-dimensional transient response to the input signal is capable of universal computation. The reservoir does not need to be trained, which makes it very well suited for optics. As such, much of the promise of photonic reservoirs lies in their minimal hardware requirements, a tremendous advantage over other hardware-intensive neural network models. We review the two main approaches to optical reservoir computing: networks implemented with multiple discrete optical nodes and the continuous system of a single nonlinear device coupled to delayed feedback.

  4. Reviving Abandoned Reservoirs with High-Pressure Air Injection: Application in a Fractured and Karsted Dolomite Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Robert Loucks; Stephen C. Ruppel; Dembla Dhiraj; Julia Gale; Jon Holder; Jeff Kane; Jon Olson; John A. Jackson; Katherine G. Jackson


    Despite declining production rates, existing reservoirs in the United States contain vast volumes of remaining oil that is not being effectively recovered. This oil resource constitutes a huge target for the development and application of modern, cost-effective technologies for producing oil. Chief among the barriers to the recovery of this oil are the high costs of designing and implementing conventional advanced recovery technologies in these mature, in many cases pressure-depleted, reservoirs. An additional, increasingly significant barrier is the lack of vital technical expertise necessary for the application of these technologies. This lack of expertise is especially notable among the small operators and independents that operate many of these mature, yet oil-rich, reservoirs. We addressed these barriers to more effective oil recovery by developing, testing, applying, and documenting an innovative technology that can be used by even the smallest operator to significantly increase the flow of oil from mature U.S. reservoirs. The Bureau of Economic Geology and Goldrus Producing Company assembled a multidisciplinary team of geoscientists and engineers to evaluate the applicability of high-pressure air injection (HPAI) in revitalizing a nearly abandoned carbonate reservoir in the Permian Basin of West Texas. The Permian Basin, the largest oil-bearing basin in North America, contains more than 70 billion barrels of remaining oil in place and is an ideal venue to validate this technology. We have demonstrated the potential of HPAI for oil-recovery improvement in preliminary laboratory tests and a reservoir pilot project. To more completely test the technology, this project emphasized detailed characterization of reservoir properties, which were integrated to access the effectiveness and economics of HPAI. The characterization phase of the project utilized geoscientists and petroleum engineers from the Bureau of Economic Geology and the Department of Petroleum

  5. Permeability Prediction for Nahr-Umr Reservoir / Subba field by Using FZI Method

    Directory of Open Access Journals (Sweden)

    Sameera M. Hamd- Allah


    Full Text Available The permeability determination in the reservoirs that are anisotropic and heterogeneous is a complicated problem due to the limited number of wells that contain core samples and well test data. This paper presents hydraulic flow units and flow zone indicator for predicting permeability of rock mass from core for Nahr-Umr reservoir/ Subba field. The Permeability measurement is better found in the laboratory work on the cored rock that taken from the formation. Nahr-Umr Formation is the main lower cretaceous sandstone reservoir in southern of Iraq. This formation is made up mainly of sandstone. Nahr-Umr formation was deposited on a gradually rising basin floor. The digenesis of Nahr-Umr sediments is very important due to its direct relation to the porosity and permeability. In this study permeability has been predicated by using the flow zone indicator methods. This method attempts to identify the flow zone indicator in un-cored wells using log records. Once the flow zone indicator is calculated from the core data, a relationship between this FZI value and the well logs can be obtained. Three relationships have been found for Nahr-Umr reservoir/Subba field by FZI method. By plotting the permeability of the core versus the permeability that is predicted by FZI method the parameter R2 was found (0.905 which is very good for predict the permeability.

  6. Estimating the geographic distribution of human Tanapox and potential reservoirs using ecological niche modeling. (United States)

    Monroe, Benjamin P; Nakazawa, Yoshinori J; Reynolds, Mary G; Carroll, Darin S


    Tanapox virus is a zoonotic infection that causes mild febrile illness and one to several nodular skin lesions. The disease is endemic in parts of Africa. The principal reservoir for the virus that causes Tanapox is unknown, but has been hypothesized to be a non-human primate. This study employs ecological niche modeling (ENM) to determine areas of tropical Africa suitable for the occurrence of human Tanapox and a list of hypothetical reservoirs. The resultant niche model will be a useful tool to guide medical surveillance activities in the region. This study uses the Desktop GARP software to predict regions where human Tanapox might be expected to occur based on historical human case locations and environmental data. Additional modeling of primate species, using occurrence data from museum records was performed to determine suitable disease reservoirs. The final ENM predicts a potential distribution of Tanapox over much of equatorial Africa, exceeding the borders of Kenya and Democratic Republic of Congo (DRC) where it has been historically reported. Five genera of non-human primates were found to be potential reservoir taxa. Validity testing suggests the model created here is robust (p modeling technique has several limitations and results should be interpreted with caution. This study may increase knowledge and engage further research in this neglected disease.

  7. hGH isoform differential immunoassays applied to blood samples from athletes: decision limits for anti-doping testing. (United States)

    Hanley, James A; Saarela, Olli; Stephens, David A; Thalabard, Jean-Christophe


    To detect hGH doping in sport, the World Anti-Doping Agency (WADA)-accredited laboratories use the ratio of the concentrations of recombinant hGH ('rec') versus other 'natural' pituitary-derived isoforms of hGH ('pit'), measured with two different kits developed specifically to detect the administration of exogenous hGH. The current joint compliance decision limits (DLs) for ratios derived from these kits, designed so that they would both be exceeded in fewer than 1 in 10,000 samples from non-doping athletes, are based on data accrued in anti-doping labs up to March 2010, and later confirmed with data up to February-March 2011. In April 2013, WADA asked the authors to analyze the now much larger set of ratios collected in routine hGH testing of athletes, and to document in the peer-reviewed literature a statistical procedure for establishing DLs, so that it be re-applied as more data become available. We examined the variation in the rec/pit ratios obtained for 21,943 screened blood (serum) samples submitted to the WADA accredited laboratories over the period 2009-2013. To fit the relevant sex- and kit-specific centiles of the logs of the ratios, we classified 'rec/pit' ratios based on low 'rec' and 'pit' values as 'negative' and fitted statistical distributions to the remaining log-ratios. The flexible data-driven quantile regression approach allowed us to deal with the fact that the location, scale and shape of the distribution of the modeled 'rec/pit' ratios varied with the concentrations of the 'rec' and 'pit' values. The between-kit correlation of the ratios was included in the fitting of the DLs, and bootstrap samples were used to quantify the estimation error in these limits. We examined the performance of these limits by applying them to the data obtained from investigator-initiated hGH administration studies, and in athletes in a simulated cycling stage race. The mean and spread of the distribution of the modeled log-ratios depended in different ways on

  8. Encapsulated microsensors for reservoir interrogation

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Eddie Elmer; Aines, Roger D.; Spadaccini, Christopher M.


    In one general embodiment, a system includes at least one microsensor configured to detect one or more conditions of a fluidic medium of a reservoir; and a receptacle, wherein the receptacle encapsulates the at least one microsensor. In another general embodiment, a method include injecting the encapsulated at least one microsensor as recited above into a fluidic medium of a reservoir; and detecting one or more conditions of the fluidic medium of the reservoir.

  9. Quench limits

    International Nuclear Information System (INIS)

    Sapinski, M.


    With thirteen beam induced quenches and numerous Machine Development tests, the current knowledge of LHC magnets quench limits still contains a lot of unknowns. Various approaches to determine the quench limits are reviewed and results of the tests are presented. Attempt to reconstruct a coherent picture emerging from these results is taken. The available methods of computation of the quench levels are presented together with dedicated particle shower simulations which are necessary to understand the tests. The future experiments, needed to reach better understanding of quench limits as well as limits for the machine operation are investigated. The possible strategies to set BLM (Beam Loss Monitor) thresholds are discussed. (author)

  10. Tidal phenomena in reservoirs; Fenomeno de mare em reservatorios

    Energy Technology Data Exchange (ETDEWEB)

    Pinilla Cortes, John Freddy


    This work models the oceanic tidal effect on reservoirs by coupling geomechanic principles with equations for fluid in a deformable porous media. The coupling revealed the importance of establishing properly the system compressibility under the various possible configurations of the loading system. The basic models for infinite reservoir, constant outer-pressure reservoir and closed reservoir were considered. It was verified that it was possible to apply the superposition of effects on the solution for the basic models by carrying a simple transformation on the solution variable. The problem was treated by in the context of test analysis, concerning dimensionless form of variables and the inclusion of well effects. The solution for the infinite reservoir including tidal effects. The solution for the infinite reservoir including tidal effects was obtained in the Laplace space and was inverted numerically by using Crump's routine. The results were incorporated to conventional type curves, and were validated by comparison with real and simulated pressure test data. Finally, alternate practices were suggested to integrate the well test analysis in reservoirs affected by the tidal effect. (author)

  11. Integration of rock typing methods for carbonate reservoir characterization

    International Nuclear Information System (INIS)

    Aliakbardoust, E; Rahimpour-Bonab, H


    Reservoir rock typing is the most important part of all reservoir modelling. For integrated reservoir rock typing, static and dynamic properties need to be combined, but sometimes these two are incompatible. The failure is due to the misunderstanding of the crucial parameters that control the dynamic behaviour of the reservoir rock and thus selecting inappropriate methods for defining static rock types. In this study, rock types were defined by combining the SCAL data with the rock properties, particularly rock fabric and pore types. First, air-displacing-water capillary pressure curues were classified because they are representative of fluid saturation and behaviour under capillary forces. Next the most important rock properties which control the fluid flow and saturation behaviour (rock fabric and pore types) were combined with defined classes. Corresponding petrophysical properties were also attributed to reservoir rock types and eventually, defined rock types were compared with relative permeability curves. This study focused on representing the importance of the pore system, specifically pore types in fluid saturation and entrapment in the reservoir rock. The most common tests in static rock typing, such as electrofacies analysis and porosity–permeability correlation, were carried out and the results indicate that these are not appropriate approaches for reservoir rock typing in carbonate reservoirs with a complicated pore system. (paper)

  12. Modeling Reservoir-River Networks in Support of Optimizing Seasonal-Scale Reservoir Operations (United States)

    Villa, D. L.; Lowry, T. S.; Bier, A.; Barco, J.; Sun, A.


    each timestep and minimize computational overhead. Power generation for each reservoir is estimated using a 2-dimensional regression that accounts for both the available head and turbine efficiency. The object-oriented architecture makes run configuration easy to update. The dynamic model inputs include inflow and meteorological forecasts while static inputs include bathymetry data, reservoir and power generation characteristics, and topological descriptors. Ensemble forecasts of hydrological and meteorological conditions are supplied in real-time by Pacific Northwest National Laboratory and are used as a proxy for uncertainty, which is carried through the simulation and optimization process to produce output that describes the probability that different operational scenario's will be optimal. The full toolset, which includes HydroSCOPE, is currently being tested on the Feather River system in Northern California and the Upper Colorado Storage Project.

  13. Reconstruction of rocks petrophysical properties as input data for reservoir modeling (United States)

    Cantucci, B.; Montegrossi, G.; Lucci, F.; Quattrocchi, F.


    The worldwide increasing energy demand triggered studies focused on defining the underground energy potential even in areas previously discharged or neglected. Nowadays, geological gas storage (CO2 and/or CH4) and geothermal energy are considered strategic for low-carbon energy development. A widespread and safe application of these technologies needs an accurate characterization of the underground, in terms of geology, hydrogeology, geochemistry, and geomechanics. However, during prefeasibility study-stage, the limited number of available direct measurements of reservoirs, and the high costs of reopening closed deep wells must be taken into account. The aim of this work is to overcome these limits, proposing a new methodology to reconstruct vertical profiles, from surface to reservoir base, of: (i) thermal capacity, (ii) thermal conductivity, (iii) porosity, and (iv) permeability, through integration of well-log information, petrographic observations on inland outcropping samples, and flow and heat transport modeling. As case study to test our procedure we selected a deep structure, located in the medium Tyrrhenian Sea (Italy). Obtained results are consistent with measured data, confirming the validity of the proposed model. Notwithstanding intrinsic limitations due to manual calibration of the model with measured data, this methodology represents an useful tool for reservoir and geochemical modelers that need to define petrophysical input data for underground modeling before the well reopening.

  14. MEOR (microbial enhanced oil recovery) data base and evaluation of reservoir characteristics for MEOR projects

    Energy Technology Data Exchange (ETDEWEB)

    Bryant, R.S.


    One aspect of NIPER's microbial enhanced oil recovery (MEOR) research program has been focused on obtaining all available information regarding the use of microorganisms in enhanced oil recovery field projects. The data have been evaluated in order to construct a data base of MEOR field projects. The data base has been used in this report to present a list of revised reservoir screening criteria for MEOR field processes. This list is by no means complete; however, until more information is available from ongoing field tests, it represents the best available data to date. The data base has been studied in this report in order to determine any significant reports from MEOR field projects where the microbial treatment was unsuccessful. Such information could indicate limitations of MEOR processes. The types of reservoir information sought from these projects that could be limitations of microorganisms include reservoir permeability, salinity, temperature, and high concentrations of minerals in the rock such as selenium, arsenic, or mercury. Unfortunately, most of the MEOR field projects to date have not reported this type of information; thus we still cannot assess field limitations until more projects report these data. 7 refs., 1 fig., 7 tabs.

  15. Testing the coherence between occupational exposure limits for inhalation and their biological limit values with a generalized PBPK-model: the case of 2-propanol and acetone. (United States)

    Huizer, Daan; Huijbregts, Mark A J; van Rooij, Joost G M; Ragas, Ad M J


    The coherence between occupational exposure limits (OELs) and their corresponding biological limit values (BLVs) was evaluated for 2-propanol and acetone. A generic human PBPK model was used to predict internal concentrations after inhalation exposure at the level of the OEL. The fraction of workers with predicted internal concentrations lower than the BLV, i.e. the 'false negatives', was taken as a measure for incoherence. The impact of variability and uncertainty in input parameters was separated by means of nested Monte Carlo simulation. Depending on the exposure scenario considered, the median fraction of the population for which the limit values were incoherent ranged from 2% to 45%. Parameter importance analysis showed that body weight was the main factor contributing to interindividual variability in blood and urine concentrations and that the metabolic parameters Vmax and Km were the most important sources of uncertainty. This study demonstrates that the OELs and BLVs for 2-propanol and acetone are not fully coherent, i.e. enforcement of BLVs may result in OELs being violated. In order to assess the acceptability of this "incoherence", a maximum population fraction at risk of exceeding the OEL should be specified as well as a minimum level of certainty in predicting this fraction. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Design and development of bio-inspired framework for reservoir operation optimization (United States)

    Asvini, M. Sakthi; Amudha, T.


    Frameworks for optimal reservoir operation play an important role in the management of water resources and delivery of economic benefits. Effective utilization and conservation of water from reservoirs helps to manage water deficit periods. The main challenge in reservoir optimization is to design operating rules that can be used to inform real-time decisions on reservoir release. We develop a bio-inspired framework for the optimization of reservoir release to satisfy the diverse needs of various stakeholders. In this work, single-objective optimization and multiobjective optimization problems are formulated using an algorithm known as "strawberry optimization" and tested with actual reservoir data. Results indicate that well planned reservoir operations lead to efficient deployment of the reservoir water with the help of optimal release patterns.

  17. Assessment of Climate Change Effects on Shahcheraghi Reservoir Inflow

    Directory of Open Access Journals (Sweden)

    M. E. Banihabib


    Full Text Available Introduction: Forecasting the inflow to the reservoir is important issues due to the limited water resources and the importance of optimal utilization of reservoirs to meet the need for drinking, industry and agriculture in future time periods. In the meantime, ignoring the effects of climate change on meteorological and hydrological parameters and water resources in long-term planning of water resources cause inaccuracy. It is essential to assess the impact of climate change on reservoir operation in arid regions. In this research, climate change impact on hydrological and meteorological variables of the Shahcheragh dam basin, in Semnan Province, was studied using an integrated model of climate change assessment. Materials and Methods: The case study area of this study was located in Damghan Township, Semnan Province, Iran. It is an arid zone. The case study area is a part of the Iran Central Desert. The basin is in 12 km north of the Damghan City and between 53° E to 54° 30’ E longitude and 36° N to 36° 30’ N latitude. The area of the basin is 1,373 km2 with average annual inflow around 17.9 MCM. Total actual evaporation and average annual rainfall are 1,986 mm and 137 mm, respectively. This case study is chosen to test proposed framework for assessment of climate change impact hydrological and meteorological variables of the basin. In the proposed model, LARS-WG and ANN sub-models (7 sub models with a combination of different inputs such as temperature, precipitation and also solar radiation were used for downscaling daily outputs of CGCM3 model under 3 emission scenarios, A2, B1 and A1B and reservoir inflow simulation, respectively. LARS-WG was tested in 99% confidence level before using it as downscaling model and feed-forward neural network was used as raifall-runoff model. Moreover, the base period data (BPD, 1990-2008, were used for calibration. Finally, reservoir inflow was simulated for future period data (FPD of 2015-2044 and

  18. Numerical simulation of groundwater movement and managed aquifer recharge from Sand Hollow Reservoir, Hurricane Bench area, Washington County, Utah (United States)

    Marston, Thomas M.; Heilweil, Victor M.


    The Hurricane Bench area of Washington County, Utah, is a 70 square-mile area extending south from the Virgin River and encompassing Sand Hollow basin. Sand Hollow Reservoir, located on Hurricane Bench, was completed in March 2002 and is operated primarily as a managed aquifer recharge project by the Washington County Water Conservancy District. The reservoir is situated on a thick sequence of the Navajo Sandstone and Kayenta Formation. Total recharge to the underlying Navajo aquifer from the reservoir was about 86,000 acre-feet from 2002 to 2009. Natural recharge as infiltration of precipitation was approximately 2,100 acre-feet per year for the same period. Discharge occurs as seepage to the Virgin River, municipal and irrigation well withdrawals, and seepage to drains at the base of reservoir dams. Within the Hurricane Bench area, unconfined groundwater-flow conditions generally exist throughout the Navajo Sandstone. Navajo Sandstone hydraulic-conductivity values from regional aquifer testing range from 0.8 to 32 feet per day. The large variability in hydraulic conductivity is attributed to bedrock fractures that trend north-northeast across the study area.A numerical groundwater-flow model was developed to simulate groundwater movement in the Hurricane Bench area and to simulate the movement of managed aquifer recharge from Sand Hollow Reservoir through the groundwater system. The model was calibrated to combined steady- and transient-state conditions. The steady-state portion of the simulation was developed and calibrated by using hydrologic data that represented average conditions for 1975. The transient-state portion of the simulation was developed and calibrated by using hydrologic data collected from 1976 to 2009. Areally, the model grid was 98 rows by 76 columns with a variable cell size ranging from about 1.5 to 25 acres. Smaller cells were used to represent the reservoir to accurately simulate the reservoir bathymetry and nearby monitoring wells; larger

  19. A quantitative method for determining a representative detection limit of the forensic luminol test for latent bloodstains. (United States)

    Cassidy, Brianna M; Lu, Zhenyu; Martin, Jennifer P; Tazik, Shawna K; Kellogg, Katie W; DeJong, Stephanie A; Belliveau, Elle O; Kilgore, Katherine E; Ervin, Samantha M; Meece-Rayle, Mackenzie; Abraham, Alyssa M; Myrick, Michael L; Morgan, Stephen L


    The luminol test has been used for over 60 years by forensic investigators for presumptive identification of blood and visualization of blood splatter patterns. Multiple studies have estimated the limit of detection (LD) for bloodstains when luminol is employed, with results ranging from 100× to 5,000,000× dilute. However, these studies typically have not identified and controlled important experimental variables which may affect the luminol LD for bloodstains. Without control of experimental parameters in the laboratory, variables which affect the potential of presumptive bloodstain test methods remain largely unknown, and comparisons required to establish new, more powerful detection methods are simply impossible. We have developed a quantitative method to determine the relationship between the amount of blood present and its reaction with luminol by measuring, under controlled conditions, the resulting chemiluminescent intensity with a video camera, combined with processing of the digital intensity data. The method resulted in an estimated LD for bloodstains on cotton fabric at ∼200,000× diluted blood with a specific luminol formulation. Although luminol is the focus of this study, the experimental protocol used could be modified to study effects of variables using other blood detection reagents. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Testing integrated behavioural and biomedical models of activity and activity limitations in a population-based sample. (United States)

    Dixon, Diane; Johnston, Marie; Elliott, Alison; Hannaford, Phil


    The predictive utility of an integrated model of disability is tested. The integrated model incorporates an impairment based model (International Classification of Functioning, Disability and Health (ICF)) and the behavioural models. Community dwelling adults (n = 628) completed a postal questionnaire measuring the integrated model. The ability of the model to predict disability in the form of activity limitations (ALs) and walking, in the full community sample and in respondents reporting chronic pain was tested. In both the community and chronic pain samples each version of the integrated model explained a majority (55%-67%) of the variance in ALs but only 11%-29% of the variance in walking behaviour (WB). Impairment directly predicted ALs but did not directly predict WB. Control related cognitions were direct predictors, and mediators, of the relationship between bodily impairment and both ALs and WB. In addition, intentions and outcome expectancies predicted WB. Self-efficacy (SE) was the most consistent predictor of both ALs and WB. An integrated model which combines psychological constructs and impairment is required for an adequate understanding of ALs. By contrast, behavioural models, but not degree of impairment, are necessary to explain activity levels.

  1. Limited Understanding of Pap Smear Testing among Women, a Barrier to Cervical Cancer Screening in the United Arab Emirates (United States)

    AL-Hammadi, Fatima Ahmed; Al-Tahri, Fatema; Al-Ali, Asma; Nair, Satish C; Abdulrahman, Mahera


    Global data indicate that cervical cancer is the fourth most common cancer among women worldwide. Important factors that affect interventions for early diagnosis of cervical cancer include social beliefs and values and poor knowledge. These may contribute to women’s participation in screening for cervical cancer and have a significant impact on decisions to take preventive action. The present study was conducted with 599 women in the UAE between September 2016 and March 2017. A cross-sectional survey was conducted to determine knowledge about cervical cancer and screening, demographic characteristics and perceived barriers. Knowledge about the Pap smear test was limited, and awareness that they should undergo the Pap smear test every three years even with an initial negative/normal Pap smear result was abysmal. In spite of the positive attitude of the women towards the Pap smear test, almost 80% of the women surveyed had no knowledge of precancerous lesions. Having higher income (21/29, 72%, p=0.027) and more miscarriages were associated with better practice of Pap smears (19/26, 73%, p=0.010). Knowledge levels were significantly higher (66.3±22.2,) that values for attitude (60.5±20.9, p= 0.03, 95% CI {0.22-11.3}, Chi-square 4.38) and practice (53.7 24.1, p= 0.001, 95% CI {6.9-18.1}, Chi-square 19.7). A well-designed health education programme on cervical cancer and benefits of screening should increase the awareness among women in UAE. One point to stress is that better communication with health professionals and improvement of access to health care services should increase the rate of cervical cancer screening. Creative Commons Attribution License

  2. Reservoir Simulations of Low-Temperature Geothermal Reservoirs (United States)

    Bedre, Madhur Ganesh

    The eastern United States generally has lower temperature gradients than the western United States. However, West Virginia, in particular, has higher temperature gradients compared to other eastern states. A recent study at Southern Methodist University by Blackwell et al. has shown the presence of a hot spot in the eastern part of West Virginia with temperatures reaching 150°C at a depth of between 4.5 and 5 km. This thesis work examines similar reservoirs at a depth of around 5 km resembling the geology of West Virginia, USA. The temperature gradients used are in accordance with the SMU study. In order to assess the effects of geothermal reservoir conditions on the lifetime of a low-temperature geothermal system, a sensitivity analysis study was performed on following seven natural and human-controlled parameters within a geothermal reservoir: reservoir temperature, injection fluid temperature, injection flow rate, porosity, rock thermal conductivity, water loss (%) and well spacing. This sensitivity analysis is completed by using ‘One factor at a time method (OFAT)’ and ‘Plackett-Burman design’ methods. The data used for this study was obtained by carrying out the reservoir simulations using TOUGH2 simulator. The second part of this work is to create a database of thermal potential and time-dependant reservoir conditions for low-temperature geothermal reservoirs by studying a number of possible scenarios. Variations in the parameters identified in sensitivity analysis study are used to expand the scope of database. Main results include the thermal potential of reservoir, pressure and temperature profile of the reservoir over its operational life (30 years for this study), the plant capacity and required pumping power. The results of this database will help the supply curves calculations for low-temperature geothermal reservoirs in the United States, which is the long term goal of the work being done by the geothermal research group under Dr. Anderson at

  3. Applications of the SWOT Mission to Reservoirs in the Mekong River Basin (United States)

    Bonnema, M.; Hossain, F.


    The forthcoming Surface Water and Ocean Topography (SWOT) mission has the potential to significantly improve our ability to observe artificial reservoirs globally from a remote sensing perspective. By providing simultaneous estimates of reservoir water surface extent and elevation with near global coverage, reservoir storage changes can be estimated. Knowing how reservoir storage changes over time is critical for understanding reservoir impacts on river systems. In data limited regions, remote sensing is often the only viable method of retrieving such information about reservoir operations. When SWOT launches in 2021, it will join an array of satellite sensors with long histories of reservoir observation and monitoring capabilities. There are many potential synergies in the complimentary use of future SWOT observations with observations from current satellite sensors. The work presented here explores the potential benefits of utilizing SWOT observations over 20 reservoirs in the Mekong River Basin. The SWOT hydrologic simulator, developed by NASA Jet Propulsion Laboratory, is used to generate realistic SWOT observations, which are then inserted into a previously established remote sensing modeling framework of the 20 Mekong Basin reservoirs. This framework currently combines data from Landsat missions, Jason radar altimeters, and the Shuttle Radar and Topography Mission (SRTM), to provide monthly estimates of reservoir storage change. The incorporation of SWOT derived reservoir surface area and elevation into the model is explored in an effort to improve both accuracy and temporal resolution of observed reservoir operations.

  4. Integrated Approach to Drilling Project in Unconventional Reservoir Using Reservoir Simulation (United States)

    Stopa, Jerzy; Wiśniowski, Rafał; Wojnarowski, Paweł; Janiga, Damian; Skrzypaszek, Krzysztof


    Accumulation and flow mechanisms in unconventional reservoir are different compared to conventional. This requires a special approach of field management with drilling and stimulation treatments as major factor for further production. Integrated approach of unconventional reservoir production optimization assumes coupling drilling project with full scale reservoir simulation for determine best well placement, well length, fracturing treatment design and mid-length distance between wells. Full scale reservoir simulation model emulate a part of polish shale - gas field. The aim of this paper is to establish influence of technical factor for gas production from shale gas field. Due to low reservoir permeability, stimulation treatment should be direct towards maximizing the hydraulic contact. On the basis of production scenarios, 15 stages hydraulic fracturing allows boost gas production over 1.5 times compared to 8 stages. Due to the possible interference of the wells, it is necessary to determine the distance between the horizontal parts of the wells trajectories. In order to determine the distance between the wells allowing to maximize recovery factor of resources in the stimulated zone, a numerical algorithm based on a dynamic model was developed and implemented. Numerical testing and comparative study show that the most favourable arrangement assumes a minimum allowable distance between the wells. This is related to the volume ratio of the drainage zone to the total volume of the stimulated zone.

  5. Effect of coherence of nonthermal reservoirs on heat transport in a microscopic collision model (United States)

    Li, Lei; Zou, Jian; Li, Hai; Xu, Bao-Ming; Wang, Yuan-Mei; Shao, Bin


    We investigate the heat transport between two nonthermal reservoirs based on a microscopic collision model. We consider a bipartite system consisting of two identical subsystems, and each subsystem interacts with its own local reservoir, which consists of a large collection of initially uncorrelated ancillas. Then a heat transport is formed between two reservoirs by a sequence of pairwise collisions (intersubsystem and subsystem-local reservoir). In this paper we consider two kinds of the reservoir's initial states: the thermal state and the state with coherence whose diagonal elements are the same as that of the thermal state and the off-diagonal elements are nonzero. In this way, we define the effective temperature of the reservoir with coherence according to its diagonal elements. We find that for two reservoirs having coherence the direction of the steady current of heat is different for different phase differences between the two initial states of two reservoirs, especially the heat can transfer from the "cold reservoir" to the "hot reservoir" in the steady regime for particular phase difference. In the limit of the effective temperature difference between the two reservoirs Δ T →0 , for most of the phase differences, the steady heat current increases with the increase of effective temperature until it reaches the high effective temperature limit, while for the thermal state or particular phase difference the steady heat current decreases with the increase of temperature at high temperatures, and in this case the conductance can be obtained.

  6. Development of TiC and TiN coated molybdenum limiter system and initial results of the thermal testing in neutral beam heated JFT-2 tokamak

    International Nuclear Information System (INIS)

    Nakamura, Hiroo; Sengoku, Seio; Maeno, Masaki; Yamamoto, Shin; Seki, Masahiro; Kazawa, Minoru


    This paper describes the limiter drive system for TiC and TiN coated molybdenum limiters and the thermal testing results of the TiC coated limiter in the JFT-2 tokamak using neutral beam injection (0.7 MW). To investigate the influence of TiC coated limiter on plasma behavior and adhesion property under tokamak plasma, a full scale limiter test has been performed in the JFT-2. Reproducible plasma was obtained after the plasma conditioning. Maximum heat flux to the limiter, measured by IR camera, was 1.5 -- 6.5 kW/cm 2 in 25 msec. Cracking, exfoliation and melting on TiC coated limiter were not observed, except for a number of arc tracks. Finally, the permissible heat fluxes of TiC coated molybdenum first wall are discussed. (author)

  7. A review of reservoir desiltation

    DEFF Research Database (Denmark)

    Brandt, Anders


    physical geography, hydrology, desilation efficiency, reservoir flushing, density-current venting, sediment slucing, erosion pattern, downstream effects, flow characteristics, sedimentation......physical geography, hydrology, desilation efficiency, reservoir flushing, density-current venting, sediment slucing, erosion pattern, downstream effects, flow characteristics, sedimentation...

  8. Reservoir sedimentation; a literature survey

    NARCIS (Netherlands)

    Sloff, C.J.


    A survey of literature is made on reservoir sedimentation, one of the most threatening processes for world-wide reservoir performance. The sedimentation processes, their impacts, and their controlling factors are assessed from a hydraulic engineering point of view with special emphasis on

  9. Chalk as a reservoir

    DEFF Research Database (Denmark)

    Fabricius, Ida Lykke

    basin, so stylolite formation in the chalk is controlled by effective burial stress. The stylolites are zones of calcite dissolution and probably are the source of calcite for porefilling cementation which is typical in water zone chalk and also affect the reservoirs to different extent. The relatively...... 50% calcite, leaving the remaining internal surface to the fine grained silica and clay. The high specific surface of these components causes clay- and silica rich intervals to have high irreducible water saturation. Although chalks typically are found to be water wet, chalk with mixed wettability...... stabilizes chemically by recrystallization. This process requires energy and is promoted by temperature. This recrystallization in principle does not influence porosity, but only specific surface, which decreases during recrystallization, causing permeability to increase. The central North Sea is a warm...

  10. Pacifiers: a microbial reservoir. (United States)

    Comina, Elodie; Marion, Karine; Renaud, François N R; Dore, Jeanne; Bergeron, Emmanuelle; Freney, Jean


    The permanent contact between the nipple part of pacifiers and the oral microflora offers ideal conditions for the development of biofilms. This study assessed the microbial contamination on the surface of 25 used pacifier nipples provided by day-care centers. Nine were made of silicone and 16 were made of latex. The biofilm was quantified using direct staining and microscopic observations followed by scraping and microorganism counting. The presence of a biofilm was confirmed on 80% of the pacifier nipples studied. This biofilm was mature for 36% of them. Latex pacifier nipples were more contaminated than silicone ones. The two main genera isolated were Staphylococcus and Candida. Our results confirm that nipples can be seen as potential reservoirs of infections. However, pacifiers do have some advantages; in particular, the potential protection they afford against sudden infant death syndrome. Strict rules of hygiene and an efficient antibiofilm cleaning protocol should be established to answer the worries of parents concerning the safety of pacifiers.

  11. Sixth workshop on geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, H.J. Jr.; Kruger, P. (eds.)


    INTRODUCTION TO THE PROCEEDINGS OF THE SIXTH GEOTHERMAL RESERVOIR ENGINEERING WORKSHOP, STANFORD GEOTHERMAL PROGRAM Henry J. Ramey, Jr., and Paul Kruger Co-Principal Investigators Ian G. Donaldson Program Manager Stanford Geothermal Program The Sixth Workshop on Geothermal Reservoir Engineering convened at Stanford University on December 16, 1980. As with previous Workshops the attendance was around 100 with a significant participation from countries other than the United States (18 attendees from 6 countries). In addition, there were a number of papers from foreign contributors not able to attend. Because of the success of all the earlier workshops there was only one format change, a new scheduling of Tuesday to Thursday rather than the earlier Wednesday through Friday. This change was in general considered for the better and will be retained for the Seventh Workshop. Papers were presented on two and a half of the three days, the panel session, this year on the numerical modeling intercomparison study sponsored by the Department of Energy, being held on the second afternoon. This panel discussion is described in a separate Stanford Geothermal Program Report (SGP-TR42). This year there was a shift in subject of the papers. There was a reduction in the number of papers offered on pressure transients and well testing and an introduction of several new subjects. After overviews by Bob Gray of the Department of Energy and Jack Howard of Lawrence Berkeley Laboratory, we had papers on field development, geopressured systems, production engineering, well testing, modeling, reservoir physics, reservoir chemistry, and risk analysis. A total of 51 papers were contributed and are printed in these Proceedings. It was, however, necessary to restrict the presentations and not all papers printed were presented. Although the content of the Workshop has changed over the years, the format to date has proved to be satisfactory. The objectives of the Workshop, the bringing together of

  12. Geothermal reservoir engineering research at Stanford University. Third annual report for the period October 1, 1982-September 30, 1983

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, H.J. Jr.; Kruger, P.; Horne, R.N.; Brigham, W.E.; Miller, F.G.


    Progress is reported in the following areas: heat extraction from hydrothermal reservoirs; radon reservoir engineering; well test analysis and bench scale experiments; field applications; workshop, seminars, and technical information; reinjection technology; and seismic monitoring of vapor/liquid interfaces. (MHR)

  13. An Intelligent Systems Approach to Reservoir Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Shahab D. Mohaghegh; Jaime Toro; Thomas H. Wilson; Emre Artun; Alejandro Sanchez; Sandeep Pyakurel


    Today, the major challenge in reservoir characterization is integrating data coming from different sources in varying scales, in order to obtain an accurate and high-resolution reservoir model. The role of seismic data in this integration is often limited to providing a structural model for the reservoir. Its relatively low resolution usually limits its further use. However, its areal coverage and availability suggest that it has the potential of providing valuable data for more detailed reservoir characterization studies through the process of seismic inversion. In this paper, a novel intelligent seismic inversion methodology is presented to achieve a desirable correlation between relatively low-frequency seismic signals, and the much higher frequency wireline-log data. Vertical seismic profile (VSP) is used as an intermediate step between the well logs and the surface seismic. A synthetic seismic model is developed by using real data and seismic interpretation. In the example presented here, the model represents the Atoka and Morrow formations, and the overlying Pennsylvanian sequence of the Buffalo Valley Field in New Mexico. Generalized regression neural network (GRNN) is used to build two independent correlation models between; (1) Surface seismic and VSP, (2) VSP and well logs. After generating virtual VSP's from the surface seismic, well logs are predicted by using the correlation between VSP and well logs. The values of the density log, which is a surrogate for reservoir porosity, are predicted for each seismic trace through the seismic line with a classification approach having a correlation coefficient of 0.81. The same methodology is then applied to real data taken from the Buffalo Valley Field, to predict inter-well gamma ray and neutron porosity logs through the seismic line of interest. The same procedure can be applied to a complete 3D seismic block to obtain 3D distributions of reservoir properties with less uncertainty than the geostatistical

  14. Nuclear stimulation of oil-reservoirs

    International Nuclear Information System (INIS)

    Delort, F.; Supiot, F.


    Underground nuclear explosions in the Hoggar nuclear test site have shown that the geological effects may increase the production of oil or gas reservoirs. By studying the permanent liquid flow-rate with approximate DUPUIT's equation, or with a computer code, it is shown that the conventional well flow-rate may be increased by a factor between 3 and 50, depending on the medium and explosion conditions. (author)

  15. Allometric Scaling and Resource Limitations Model of Tree Heights: Part 3. Model Optimization and Testing over Continental China

    Directory of Open Access Journals (Sweden)

    Xiliang Ni


    Full Text Available The ultimate goal of our multi-article series is to demonstrate the Allometric Scaling and Resource Limitation (ASRL approach for mapping tree heights and biomass. This third article tests the feasibility of the optimized ASRL model over China at both site (14 meteorological stations and continental scales. Tree heights from the Geoscience Laser Altimeter System (GLAS waveform data are used for the model optimizations. Three selected ASRL parameters (area of single leaf, α; exponent for canopy radius, η; and root absorption efficiency, γ are iteratively adjusted to minimize differences between the references and predicted tree heights. Key climatic variables (e.g., temperature, precipitation, and solar radiation are needed for the model simulations. We also exploit the independent GLAS and in situ tree heights to examine the model performance. The predicted tree heights at the site scale are evaluated against the GLAS tree heights using a two-fold cross validation (RMSE = 1.72 m; R2 = 0.97 and bootstrapping (RMSE = 4.39 m; R2 = 0.81. The modeled tree heights at the continental scale (1 km spatial resolution are compared to both GLAS (RMSE = 6.63 m; R2 = 0.63 and in situ (RMSE = 6.70 m; R2 = 0.52 measurements. Further, inter-comparisons against the existing satellite-based forest height maps have resulted in a moderate degree of agreements. Our results show that the optimized ASRL model is capable of satisfactorily retrieving tree heights over continental China at both scales. Subsequent studies will focus on the estimation of woody biomass after alleviating the discussed limitations.

  16. Advances in photonic reservoir computing

    Directory of Open Access Journals (Sweden)

    Van der Sande Guy


    Full Text Available We review a novel paradigm that has emerged in analogue neuromorphic optical computing. The goal is to implement a reservoir computer in optics, where information is encoded in the intensity and phase of the optical field. Reservoir computing is a bio-inspired approach especially suited for processing time-dependent information. The reservoir’s complex and high-dimensional transient response to the input signal is capable of universal computation. The reservoir does not need to be trained, which makes it very well suited for optics. As such, much of the promise of photonic reservoirs lies in their minimal hardware requirements, a tremendous advantage over other hardware-intensive neural network models. We review the two main approaches to optical reservoir computing: networks implemented with multiple discrete optical nodes and the continuous system of a single nonlinear device coupled to delayed feedback.

  17. Gravity observations for hydrocarbon reservoir monitoring

    NARCIS (Netherlands)

    Glegola, M.A.


    In this thesis the added value of gravity observations for hydrocarbon reservoir monitoring and characterization is investigated. Reservoir processes and reservoir types most suitable for gravimetric monitoring are identified. Major noise sources affecting time-lapse gravimetry are analyzed. The

  18. Analysis of real-time reservoir monitoring : reservoirs, strategies, & modeling.

    Energy Technology Data Exchange (ETDEWEB)

    Mani, Seethambal S.; van Bloemen Waanders, Bart Gustaaf; Cooper, Scott Patrick; Jakaboski, Blake Elaine; Normann, Randy Allen; Jennings, Jim (University of Texas at Austin, Austin, TX); Gilbert, Bob (University of Texas at Austin, Austin, TX); Lake, Larry W. (University of Texas at Austin, Austin, TX); Weiss, Chester Joseph; Lorenz, John Clay; Elbring, Gregory Jay; Wheeler, Mary Fanett (University of Texas at Austin, Austin, TX); Thomas, Sunil G. (University of Texas at Austin, Austin, TX); Rightley, Michael J.; Rodriguez, Adolfo (University of Texas at Austin, Austin, TX); Klie, Hector (University of Texas at Austin, Austin, TX); Banchs, Rafael (University of Texas at Austin, Austin, TX); Nunez, Emilio J. (University of Texas at Austin, Austin, TX); Jablonowski, Chris (University of Texas at Austin, Austin, TX)


    The project objective was to detail better ways to assess and exploit intelligent oil and gas field information through improved modeling, sensor technology, and process control to increase ultimate recovery of domestic hydrocarbons. To meet this objective we investigated the use of permanent downhole sensors systems (Smart Wells) whose data is fed real-time into computational reservoir models that are integrated with optimized production control systems. The project utilized a three-pronged approach (1) a value of information analysis to address the economic advantages, (2) reservoir simulation modeling and control optimization to prove the capability, and (3) evaluation of new generation sensor packaging to survive the borehole environment for long periods of time. The Value of Information (VOI) decision tree method was developed and used to assess the economic advantage of using the proposed technology; the VOI demonstrated the increased subsurface resolution through additional sensor data. Our findings show that the VOI studies are a practical means of ascertaining the value associated with a technology, in this case application of sensors to production. The procedure acknowledges the uncertainty in predictions but nevertheless assigns monetary value to the predictions. The best aspect of the procedure is that it builds consensus within interdisciplinary teams The reservoir simulation and modeling aspect of the project was developed to show the capability of exploiting sensor information both for reservoir characterization and to optimize control of the production system. Our findings indicate history matching is improved as more information is added to the objective function, clearly indicating that sensor information can help in reducing the uncertainty associated with reservoir characterization. Additional findings and approaches used are described in detail within the report. The next generation sensors aspect of the project evaluated sensors and packaging

  19. Cytological preparations for molecular analysis: A review of technical procedures, advantages and limitations for referring samples for testing. (United States)

    da Cunha Santos, G; Saieg, M A; Troncone, G; Zeppa, P


    Minimally invasive procedures such as endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) must yield not only good quality and quantity of material for morphological assessment, but also an adequate sample for analysis of molecular markers to guide patients to appropriate targeted therapies. In this context, cytopathologists worldwide should be familiar with minimum requirements for refereeing cytological samples for testing. The present manuscript is a review with comprehensive description of the content of the workshop entitled Cytological preparations for molecular analysis: pre-analytical issues for EBUS TBNA, presented at the 40th European Congress of Cytopathology in Liverpool, UK. The present review emphasises the advantages and limitations of different types of cytology substrates used for molecular analysis such as archival smears, liquid-based preparations, archival cytospin preparations and FTA (Flinders Technology Associates) cards, as well as their technical requirements/features. These various types of cytological specimens can be successfully used for an extensive array of molecular studies, but the quality and quantity of extracted nucleic acids rely directly on adequate pre-analytical assessment of those samples. In this setting, cytopathologists must not only be familiar with the different types of specimens and associated technical procedures, but also correctly handle the material provided by minimally invasive procedures, ensuring that there is sufficient amount of material for a precise diagnosis and correct management of the patient through personalised care. © 2018 John Wiley & Sons Ltd.

  20. Limited-information goodness-of-fit testing of item response theory models for sparse 2 tables. (United States)

    Cai, Li; Maydeu-Olivares, Albert; Coffman, Donna L; Thissen, David


    Bartholomew and Leung proposed a limited-information goodness-of-fit test statistic (Y) for models fitted to sparse 2(P ) contingency tables. The null distribution of Y was approximated using a chi-squared distribution by matching moments. The moments were derived under the assumption that the model parameters were known in advance and it was conjectured that the approximation would also be appropriate when the parameters were to be estimated. Using maximum likelihood estimation of the two-parameter logistic item response theory model, we show that the effect of parameter estimation on the distribution of Y is too large to be ignored. Consequently, we derive the asymptotic moments of Y for maximum likelihood estimation. We show using a simulation study that when the null distribution of Y is approximated using moments that take into account the effect of estimation, Y becomes a very useful statistic to assess the overall goodness of fit of models fitted to sparse 2(P) tables.

  1. The first Italian superconducting fault current limiter: Results of the field testing experience after one year operation

    International Nuclear Information System (INIS)

    Martini, L; Bocchi, M; Ascade, M; Valzasina, A; Rossi, V; Angeli, G; Ravetta, C


    Ricerca sul Sistema Energetico S.p.A. (RSE) has been gaining a relevant experience in the simulation, design and installation of resistive-type Superconducting Fault Current Limiter (SFCL) devices for more than five years in the framework of a R and D national project funded by the Ricerca di Sistema (RdS). The most recent outcome of this research activity is the installation of a resistive-type BSCCO-based 9 kV / 3.4 MVA SFCL device in a single feeder branch of the Medium Voltage (MV) distribution network managed by A2A Reti Elettriche S.p.A (A2A) in the Milano area. This installation represents the first SFCL successfully installed in Italy. In this paper, we report on the main outcomes after a more than 1-year long steady-state field testing activity. The design of an upgraded device to be installed in the same substation has already been initiated: the new SFCL will allow to protect four different feeders, therefore implying a device upgrade up to 15.6 MVA.

  2. Hantavirus Immunology of Rodent Reservoirs: Current Status and Future Directions

    Directory of Open Access Journals (Sweden)

    Tony Schountz


    Full Text Available Hantaviruses are hosted by rodents, insectivores and bats. Several rodent-borne hantaviruses cause two diseases that share many features in humans, hemorrhagic fever with renal syndrome in Eurasia or hantavirus cardiopulmonary syndrome in the Americas. It is thought that the immune response plays a significant contributory role in these diseases. However, in reservoir hosts that have been closely examined, little or no pathology occurs and infection is persistent despite evidence of adaptive immune responses. Because most hantavirus reservoirs are not model organisms, it is difficult to conduct meaningful experiments that might shed light on how the viruses evade sterilizing immune responses and why immunopathology does not occur. Despite these limitations, recent advances in instrumentation and bioinformatics will have a dramatic impact on understanding reservoir host responses to hantaviruses by employing a systems biology approach to identify important pathways that mediate virus/reservoir relationships.

  3. Sediment Characteristics of Tennessee Streams and Reservoirs

    National Research Council Canada - National Science Library

    Trimble, Stanley W; Carey, William P


    Suspended-sediment and reservoir sedimentation data have been analyzed to determine sediment yields and transport characteristics of Tennessee streams Data from 31 reservoirs plus suspended-sediment...

  4. Current limiters

    Energy Technology Data Exchange (ETDEWEB)

    Loescher, D.H. [Sandia National Labs., Albuquerque, NM (United States). Systems Surety Assessment Dept.; Noren, K. [Univ. of Idaho, Moscow, ID (United States). Dept. of Electrical Engineering


    The current that flows between the electrical test equipment and the nuclear explosive must be limited to safe levels during electrical tests conducted on nuclear explosives at the DOE Pantex facility. The safest way to limit the current is to use batteries that can provide only acceptably low current into a short circuit; unfortunately this is not always possible. When it is not possible, current limiters, along with other design features, are used to limit the current. Three types of current limiters, the fuse blower, the resistor limiter, and the MOSFET-pass-transistor limiters, are used extensively in Pantex test equipment. Detailed failure mode and effects analyses were conducted on these limiters. Two other types of limiters were also analyzed. It was found that there is no best type of limiter that should be used in all applications. The fuse blower has advantages when many circuits must be monitored, a low insertion voltage drop is important, and size and weight must be kept low. However, this limiter has many failure modes that can lead to the loss of over current protection. The resistor limiter is simple and inexpensive, but is normally usable only on circuits for which the nominal current is less than a few tens of milliamperes. The MOSFET limiter can be used on high current circuits, but it has a number of single point failure modes that can lead to a loss of protective action. Because bad component placement or poor wire routing can defeat any limiter, placement and routing must be designed carefully and documented thoroughly.

  5. Changes to the Bakomi Reservoir

    Directory of Open Access Journals (Sweden)

    Kubinský Daniel


    Full Text Available This article is focused on the analysis and evaluation of the changes of the bottom of the Bakomi reservoir, the total volume of the reservoir, ecosystems, as well as changes in the riparian zone of the Bakomi reservoir (situated in the central Slovakia. Changes of the water component of the reservoir were subject to the deposition by erosion-sedimentation processes, and were identifed on the basis of a comparison of the present relief of the bottom of reservoir obtained from feld measurements (in 2011 with the relief measurements of the bottom obtained from the 1971 historical maps, (i.e. over a period of 40 years. Changes of landscape structures of the riparian zone have been mapped for the time period of 1949–2013; these changes have been identifed with the analysis of ortophotomaps and the feld survey. There has been a signifcant rise of disturbed shores with low herb grassland. Over a period of 40 years, there has been a deposition of 667 m3 of sediments. The results showed that there were no signifcant changes in the local ecosystems of the Bakomi reservoir in comparison to the other reservoirs in the vicinity of Banská Štiavnica.

  6. Relative influence of deposition and diagenesis on carbonate reservoir layering

    Energy Technology Data Exchange (ETDEWEB)

    Poli, Emmanuelle [Total E and P, Courbevoie (France); Javaux, Catherine [Total E and P, Pointe Noire (Congo)


    The architecture heterogeneities and petrophysical properties of carbonate reservoirs result from a combination of platform morphology, related depositional environments, relative sea level changes and diagenetic events. The reservoir layering built for static and dynamic modelling purposes should reflect the key heterogeneities (depositional or diagenetic) which govern the fluid flow patterns. The layering needs to be adapted to the goal of the modelling, ranging from full field computations of hydrocarbon volumes, to sector-based fine-scale simulations to test the recovery improvement. This paper illustrates various reservoir layering types, including schemes dominated by depositional architecture, and those more driven by the diagenetic overprint. The examples include carbonate platform reservoirs from different stratigraphic settings (Tertiary, Cretaceous, Jurassic and Permian) and different regions (Europe, Africa and Middle East areas). This review shows how significant stratigraphic surfaces (such as sequence boundaries or maximum flooding) with their associated facies shifts, can be often considered as key markers to constrain the reservoir layering. Conversely, how diagenesis (dolomitization and karst development), resulting in units with particular poroperm characteristics, may significantly overprint the primary reservoir architecture by generating flow units which cross-cut depositional sequences. To demonstrate how diagenetic processes can create reservoir bodies with geometries that cross-cut the depositional fabric, different types of dolomitization and karst development are illustrated. (author)

  7. Validation of an impact limiter crush prediction model with test data: the case of the HI-STAR 100 package

    International Nuclear Information System (INIS)

    Singh, K.P.; Soler, A.I.; Bullard, C.W.


    An impact limiter is an essential appurtenance in a Part 71 transport package. The impact limiter serves to protect the cask contents from excessive deceleration in the event of a mechanical accident. 10CFR71.73 (as do the IAEA regulations) specifies a drop height of 9 meters (30 feet) onto an essentially rigid surface as the design requirement for the impact limiter. The orientation of the cask relative to the ''target'' at the instance of the impact, however, is not specified in the regulations. Therefore, the impact limiter must be capable of limiting the cask's deceleration to a prescribed limit regardless of the cask's orientation at impact. In addition to the indeterminacy with respect to the orientation at impact, the impact limiter must be capable of performing its intended function under a wide range of ambient conditions, ranging from -20 F to 100 F, and relative humidity from zero to 100%

  8. Evaluation of impact limiter performance during end-on and slapdown drop tests of a one-third scale model storage/transport cask system

    International Nuclear Information System (INIS)

    Yoshimura, H.R.; Bronowski, D.R.; Uncapher, W.L.; Attaway, S.W.; Bateman, V.I.; Carne, T.G.; Gregory, D.L.; Huerta, M.


    This report describes drop testing of a one-third scale model shipping cask system. Two casks were designed and fabricated by Transnuclear, Inc., to ship spent fuel from the former Nuclear Fuel Services West Valley reprocessing facility in New York to the Idaho National Engineering Laboratory for a long-term spent fuel dry storage demonstration project. As part of the NRC's regulatory certification process, one-third scale model tests were performed to obtain experimental data on impact limiter performance during impact testing. The objectives of the testing program were to (1) obtain deceleration and displacement information for the cask and impact limiter system, (2) obtain dynamic force-displacement data for the impact limiters, (3) verify the integrity of the impact limiter retention system, and (4) examine the crush behavior of the limiters. Two 30-ft (9-m) drop tests were conducted on a mass model of the cask body and scaled balsa and redwood-filled impact limiters. This report describes the results of both tests in terms of measured decelerations, posttest deformation measurements, and the general structural response of the system. 3 refs., 32 figs

  9. A reservoir simulation approach for modeling of naturally fractured reservoirs

    Directory of Open Access Journals (Sweden)

    H. Mohammadi


    Full Text Available In this investigation, the Warren and Root model proposed for the simulation of naturally fractured reservoir was improved. A reservoir simulation approach was used to develop a 2D model of a synthetic oil reservoir. Main rock properties of each gridblock were defined for two different types of gridblocks called matrix and fracture gridblocks. These two gridblocks were different in porosity and permeability values which were higher for fracture gridblocks compared to the matrix gridblocks. This model was solved using the implicit finite difference method. Results showed an improvement in the Warren and Root model especially in region 2 of the semilog plot of pressure drop versus time, which indicated a linear transition zone with no inflection point as predicted by other investigators. Effects of fracture spacing, fracture permeability, fracture porosity, matrix permeability and matrix porosity on the behavior of a typical naturally fractured reservoir were also presented.

  10. Field Demonstration of Horizontal Infill Drilling Using Cost-effective Integrated Reservoir Modeling--Mississippian Carbonates, Central Kansas

    Energy Technology Data Exchange (ETDEWEB)

    Saibal Bhattacharya


    Mississippian carbonate reservoirs have produced in excess of 1 billion barrels of oil in Kansas accounting for over 16% of the state's production. With declining production from other age reservoirs, the contribution of Mississippian reservoirs to Kansas's oil production has risen to 43% as of 2004. However, solution-enhanced features such as vertical shale intervals extending from the karst erosional surface at the top introduce complexities/compartmentalizations in Mississippian carbonate reservoirs. Coupled with this, strong water drives charge many of these reservoirs resulting in limited drainage from vertical wells due to high water cuts after an initial period of low water production. Moreover, most of these fields are operated by small independent operators without access to the knowledge bank of modern research in field characterization and exploitation/development practices. Thus, despite increasing importance of Mississippian fields to Kansas production, these fields are beset with low recovery factors and high abandonment rates leaving significant resources in the ground. Worldwide, horizontal infill wells have been successful in draining compartmentalized reservoirs with limited pressure depletion. The intent of this project was to demonstrate the application of horizontal wells to successfully exploit the remaining potential in mature Mississippian fields of the mid-continent. However, it is of critical importance that for horizontal wells to be economically successful, they must be selectively targeted. This project demonstrated the application of initial and secondary screening methods, based on publicly available data, to quickly shortlist fields in a target area for detailed studies to evaluate their potential to infill horizontal well applications. Advanced decline curve analyses were used to estimate missing well-level production data and to verify if the well produced under unchanging bottom-hole conditions--two commonly occurring

  11. Permeability restoration in underground disposal reservoirs

    International Nuclear Information System (INIS)

    Grubbs, D.M.; Haynes, C.D.; Whittle, G.P.


    The aim of the research performed was to explore methods of permeability restoration in underground disposal reservoirs that may improve the receptive capacity of a well to a level that will allow continued use of the disposal zone without resorting to elevated injection pressures. The laboratory investigation employed a simulated open-hole completion in a disposal well wherein the entire formation face is exposed to the well bore. Cylindrical core samples from representative reservoir rocks through which a central vertical opening or borehole had been drilled were injected with a liquid waste obtained from a chemical manufacturing plant. This particular waste material was found to have a moderate plugging effect when injected into samples of reservoir rocks in a prior study. A review was made of the chemical considerations that might account for the reduction of permeability in waste injection. Purpose of this study was to ascertain the conditions under which the precipitation of certain compounds might occur in the injection of the particular waste liquid employed. A summary of chemical calculations is contained in Appendix B. The data may be useful in the treatment of wastes prior to injection and in the design of restoration procedures where analyses of waste liquids and interstitial materials are available. The results of permeability restoration tests were analyzed mathematically by curve-fitting techniques performed by a digital computer. A summary of the analyses is set forth in the discussion of test results and examples of computer printouts are included in Appendix A

  12. GRACE water storage estimates for the Middle East and other regions with significant reservoir and lake storage (United States)

    Longuevergne, L.; Wilson, C. R.; Scanlon, B. R.; Crétaux, J. F.


    While GRACE (Gravity Recovery and Climate Experiment) satellites are increasingly being used to monitor total water storage (TWS) changes globally, the impact of spatial distribution of water storage within a basin is generally ignored but may be substantial. In many basins, water is often stored in reservoirs or lakes, flooded areas, small aquifer systems, and other localized regions with areas typically below GRACE resolution (~200 000 km2). The objective of this study was to assess the impact of nonuniform water storage distribution on GRACE estimates of TWS changes as basin-wide averages, focusing on surface water reservoirs and using a priori information on reservoir storage from radar altimetry. Analysis included numerical experiments testing effects of location and areal extent of the localized mass (reservoirs) within a basin on basin-wide average water storage changes, and application to the lower Nile (Lake Nasser) and Tigris-Euphrates basins as examples. Numerical experiments show that by assuming uniform mass distribution, GRACE estimates may under- or overestimate basin-wide average water storage by up to a factor of ~2, depending on reservoir location and areal extent. Although reservoirs generally cover less than 1% of the basin area, and their spatial extent may be unresolved by GRACE, reservoir storage may dominate water storage changes in some basins. For example, reservoir storage accounts for ~95% of seasonal water storage changes in the lower Nile and 10% in the Tigris-Euphrates. Because reservoirs are used to mitigate droughts and buffer against climate extremes, their influence on interannual timescales can be large. For example, TWS decline during the 2007-2009 drought in the Tigris-Euphrates basin measured by GRACE was ~93 km3. Actual reservoir storage from satellite altimetry was limited to 27 km3, but their apparent impact on GRACE reached 45 km3, i.e., 50% of GRACE trend. Therefore, the actual impact of reservoirs would have been greatly


    Directory of Open Access Journals (Sweden)

    Niculae Iulian TEODORESCU


    Full Text Available The Surduc reservoir was projected to ensure more water when water is scarce and to thus provide especially the city Timisoara, downstream of it with water.The accumulation is placed on the main affluent of the Bega river, Gladna in the upper part of its watercourse.The dam behind which this accumulation was created is of a frontal type made of enrochements with a masque made of armed concrete on the upstream part and protected/sustained by grass on the downstream. The dam is 130m long on its coping and a constructed height of 34 m. It is also endowed with spillway for high water and two bottom outlets formed of two conduits, at the end of which is the microplant. The second part of my paper deals with the hydrometric analysis of the Accumulation Surduc and its impact upon the flow, especially the maximum run-off. This influence is exemplified through the high flood from the 29th of July 1980, the most significant flood recorded in the basin with an apparition probability of 0.002%.

  14. Third workshop on geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Ramey, H.J. Jr.; Kruger, P. (eds.)


    The Third Workshop on Geothermal Reservoir Engineering convened at Stanford University on December 14, 1977, with 104 attendees from six nations. In keeping with the recommendations expressed by the participants at the Second Workshop, the format of the Workshop was retained, with three days of technical sessions devoted to reservoir physics, well and reservoir testing, field development, and mathematical modeling of geothermal reservoirs. The program presented 33 technical papers, summaries of which are included in these Proceedings. Although the format of the Workshop has remained constant, it is clear from a perusal of the Table of Contents that considerable advances have occurred in all phases of geothermal reservoir engineering over the past three years. Greater understanding of reservoir physics and mathematical representations of vapor-dominated and liquid-dominated reservoirs are evident; new techniques for their analysis are being developed, and significant field data from a number of newer reservoirs are analyzed. The objectives of these workshops have been to bring together researchers active in the various physical and mathematical disciplines comprising the field of geothermal reservoir engineering, to give the participants a forum for review of progress and exchange of new ideas in this rapidly developing field, and to summarize the effective state of the art of geothermal reservoir engineering in a form readily useful to the many government and private agencies involved in the development of geothermal energy. To these objectives, the Third Workshop and these Proceedings have been successfully directed. Several important events in this field have occurred since the Second Workshop in December 1976. The first among these was the incorporation of the Energy Research and Development Administration (ERDA) into the newly formed Department of Energy (DOE) which continues as the leading Federal agency in geothermal reservoir engineering research. The Third



    Henryk Kasza


    The aim of this study was to assess a trophic state of reservoirs in southern Poland under diversified human impact with different morphological, hydrological and river basin features. Three reservoirs were studied: Wapienica, Goczałkowice and Łąka. To estimate a trophic state of reservoir waters criteria based on measured total nitrogen, total phosphorous and chlorophyll a concentrations and limiting values of trophies differentiation as well as the Carlson trophic index (TSI) were used. Rel...

  16. Understanding the True Stimulated Reservoir Volume in Shale Reservoirs

    KAUST Repository

    Hussain, Maaruf


    Successful exploitation of shale reservoirs largely depends on the effectiveness of hydraulic fracturing stimulation program. Favorable results have been attributed to intersection and reactivation of pre-existing fractures by hydraulically-induced fractures that connect the wellbore to a larger fracture surface area within the reservoir rock volume. Thus, accurate estimation of the stimulated reservoir volume (SRV) becomes critical for the reservoir performance simulation and production analysis. Micro-seismic events (MS) have been commonly used as a proxy to map out the SRV geometry, which could be erroneous because not all MS events are related to hydraulic fracture propagation. The case studies discussed here utilized a fully 3-D simulation approach to estimate the SRV. The simulation approach presented in this paper takes into account the real-time changes in the reservoir\\'s geomechanics as a function of fluid pressures. It is consisted of four separate coupled modules: geomechanics, hydrodynamics, a geomechanical joint model for interfacial resolution, and an adaptive re-meshing. Reservoir stress condition, rock mechanical properties, and injected fluid pressure dictate how fracture elements could open or slide. Critical stress intensity factor was used as a fracture criterion governing the generation of new fractures or propagation of existing fractures and their directions. Our simulations were run on a Cray XC-40 HPC system. The studies outcomes proved the approach of using MS data as a proxy for SRV to be significantly flawed. Many of the observed stimulated natural fractures are stress related and very few that are closer to the injection field are connected. The situation is worsened in a highly laminated shale reservoir as the hydraulic fracture propagation is significantly hampered. High contrast in the in-situ stresses related strike-slip developed thereby shortens the extent of SRV. However, far field nature fractures that were not connected to

  17. Sampling from stochastic reservoir models constrained by production data

    Energy Technology Data Exchange (ETDEWEB)

    Hegstad, Bjoern Kaare


    When a petroleum reservoir is evaluated, it is important to forecast future production of oil and gas and to assess forecast uncertainty. This is done by defining a stochastic model for the reservoir characteristics, generating realizations from this model and applying a fluid flow simulator to the realizations. The reservoir characteristics define the geometry of the reservoir, initial saturation, petrophysical properties etc. This thesis discusses how to generate realizations constrained by production data, that is to say, the realizations should reproduce the observed production history of the petroleum reservoir within the uncertainty of these data. The topics discussed are: (1) Theoretical framework, (2) History matching, forecasting and forecasting uncertainty, (3) A three-dimensional test case, (4) Modelling transmissibility multipliers by Markov random fields, (5) Up scaling, (6) The link between model parameters, well observations and production history in a simple test case, (7) Sampling the posterior using optimization in a hierarchical model, (8) A comparison of Rejection Sampling and Metropolis-Hastings algorithm, (9) Stochastic simulation and conditioning by annealing in reservoir description, and (10) Uncertainty assessment in history matching and forecasting. 139 refs., 85 figs., 1 tab.

  18. Chickamauga reservoir embayment study - 1990

    Energy Technology Data Exchange (ETDEWEB)

    Meinert, D.L.; Butkus, S.R.; McDonough, T.A.


    The objectives of this report are three-fold: (1) assess physical, chemical, and biological conditions in the major embayments of Chickamauga Reservoir; (2) compare water quality and biological conditions of embayments with main river locations; and (3) identify any water quality concerns in the study embayments that may warrant further investigation and/or management actions. Embayments are important areas of reservoirs to be considered when assessments are made to support water quality management plans. In general, embayments, because of their smaller size (water surface areas usually less than 1000 acres), shallower morphometry (average depth usually less than 10 feet), and longer detention times (frequently a month or more), exhibit more extreme responses to pollutant loadings and changes in land use than the main river region of the reservoir. Consequently, embayments are often at greater risk of water quality impairments (e.g. nutrient enrichment, filling and siltation, excessive growths of aquatic plants, algal blooms, low dissolved oxygen concentrations, bacteriological contamination, etc.). Much of the secondary beneficial use of reservoirs occurs in embayments (viz. marinas, recreation areas, parks and beaches, residential development, etc.). Typically embayments comprise less than 20 percent of the surface area of a reservoir, but they often receive 50 percent or more of the water-oriented recreational use of the reservoir. This intensive recreational use creates a potential for adverse use impacts if poor water quality and aquatic conditions exist in an embayment.

  19. Fracture-network analysis of the Latemar Platform (northern Italy): integrating outcrop studies to constrain the hydraulic properties of fractures in reservoir models

    NARCIS (Netherlands)

    Boro, H.; Rosero, E.; Bertotti, G.V.


    Fractures in subsurface reservoirs are known to have significant impacts on reservoir productivity. Quantifying their importance, however, is challenged by limited subsurface observations, and intense computations for modelling and upscaling. In this paper, we present a workflow to construct and

  20. Reservoir characterization of Pennsylvanian Sandstone Reservoirs. Annual report

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, M.


    This annual report describes the progress during the second year of a project on Reservoir Characterization of Pennsylvanian Sandstone Reservoirs. The report is divided into three sections: (i) reservoir description and scale-up procedures; (ii) outcrop investigation; (iii) in-fill drilling potential. The first section describes the methods by which a reservoir can be characterized, can be described in three dimensions, and can be scaled up with respect to its properties, appropriate for simulation purposes. The second section describes the progress on investigation of an outcrop. The outcrop is an analog of Bartlesville Sandstone. We have drilled ten wells behind the outcrop and collected extensive log and core data. The cores have been slabbed, photographed and the several plugs have been taken. In addition, minipermeameter is used to measure permeabilities on the core surface at six inch intervals. The plugs have been analyzed for the permeability and porosity values. The variations in property values will be tied to the geological descriptions as well as the subsurface data collected from the Glen Pool field. The third section discusses the application of geostatistical techniques to infer in-fill well locations. The geostatistical technique used is the simulated annealing technique because of its flexibility. One of the important reservoir data is the production data. Use of production data will allow us to define the reservoir continuities, which may in turn, determine the in-fill well locations. The proposed technique allows us to incorporate some of the production data as constraints in the reservoir descriptions. The technique has been validated by comparing the results with numerical simulations.

  1. Influence of limnological zones on the spatial distribution of fish assemblages in three Brazilian reservoirs

    Directory of Open Access Journals (Sweden)

    Bárbara Becker


    Full Text Available Reservoirs can have both positive and negative effects on differing fish species depending on the species concerned and reservoir morphology, flow regime, and basin location.  We assessed the influence of limnological zones on the ichthyofauna of three large Neotropical reservoirs in two different river basins. We sampled fish through use of gill nets set at 40 systematically selected sites on each reservoir. We used satellite images, algae, and suspended solids concentrations to classify those sites as lacustrine or riverine. We observed significant differences in assemblage composition between riverine and lacustrine zones of each reservoir. We either tested if the same region (lacustrine or riverine showed the same patterns in different reservoirs. In São Simão, the riverine zone produced greater abundances of native species, long-distance migratory species, diversity, and richness, whereas the lacustrine zone supported greater total and non-native species abundances. Conversely, in Três Marias, the riverine zone supported greater total and non-native species abundances, whereas the others traits evaluated did not differ significantly between zones. Only lacustrine sites occurred in Volta Grande Reservoir. The same zones in the three reservoirs usually had significantly different patterns in the traits evaluated. The differences in spatial patterns observed between reservoirs could be explained partly by the differing morphologies (complex versus linear, the differential influence of tributaries of each reservoir and basin positions (presence or absence of upstream dams of the reservoirs.

  2. Energy R and D. Geothermal energy and underground reservoirs; R et D energie. Geothermie et reservoirs souterrains

    Energy Technology Data Exchange (ETDEWEB)



    Geothermal energy appears as a viable economic alternative among the different renewable energy sources. The French bureau of geological and mining researches (BRGM) is involved in several research and development programs in the domain of geothermal energy and underground reservoirs. This document presents the content of 5 programs: the deep hot dry rock system of Soultz-sous-Forets (construction and testing of the scientific pilot, modeling of the reservoir structure), the development of low and high enthalpy geothermal energy in the French West Indies, the comparison of the geothermal development success of Bouillante (Guadeloupe, French West Indies) with the check of the geothermal development of Nyssiros (Greece) and Pantelleria (Italy), the development of the high enthalpy geothermal potentialities of Reunion Island, and the underground storage of CO{sub 2} emissions in geologic formations (deep aquifers, geothermal reservoirs, abandoned mines or oil reservoirs). (J.S.)

  3. Setting limits for acceptable change in sediment particle size composition: testing a new approach to managing marine aggregate dredging. (United States)

    Cooper, Keith M


    A baseline dataset from 2005 was used to identify the spatial distribution of macrofaunal assemblages across the eastern English Channel. The range of sediment composition found in association with each assemblage was used to define limits for acceptable change at ten licensed marine aggregate extraction areas. Sediment data acquired in 2010, 4 years after the onset of dredging, were used to assess whether conditions remained within the acceptable limits. Despite the observed changes in sediment composition, the composition of sediments in and around nine extraction areas remained within pre-defined acceptable limits. At the tenth site, some of the observed changes within the licence area were judged to have gone beyond the acceptable limits. Implications of the changes are discussed, and appropriate management measures identified. The approach taken in this study offers a simple, objective and cost-effective method for assessing the significance of change, and could simplify the existing monitoring regime. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Potential and limitations of radionuclide-based exercise testing before and after operation in the patient with coronary artery disease

    International Nuclear Information System (INIS)

    Borer, J.S.; Phillips, P.; Jacobstein, J.


    The authors assess the potential benefits and limitations of radionuclide cineangiography when used to select patients with ischemic heart disease for operation, to precisely plan the operation, and to assess the effects of such therapy. The results indicate that this technique provides potentially important benefits, but also several limitations. Additional studies are required to clarify the optimal role for this technique in the evaluation of the patient with coronary artery disease. (Auth.)

  5. Gravity observations for hydrocarbon reservoir monitoring


    Glegola, M.A.


    In this thesis the added value of gravity observations for hydrocarbon reservoir monitoring and characterization is investigated. Reservoir processes and reservoir types most suitable for gravimetric monitoring are identified. Major noise sources affecting time-lapse gravimetry are analyzed. The added value of gravity data for reservoir monitoring and characterization is analyzed within closed-loop reservoir management concept. Synthetic 2D and 3D numerical experiments are performed where var...

  6. Temporal Asynchrony of Trophic Status Between Mainstream and Tributary Bay Within a Giant Dendritic Reservoir: The Role of Local-Scale Regulators. (United States)

    Xu, Yaoyang; Shao, Meiling; Han, Xinqin; Cai, Qinghua


    Limnologists have regarded temporal coherence (synchrony) as a powerful tool for identifying the relative importance of local-scale regulators and regional climatic drivers on lake ecosystems. Limnological studies on Asian reservoirs have emphasized that climate and hydrology under the influences of monsoon are dominant factors regulating seasonal patterns of lake trophic status; yet, little is known of synchrony or asynchrony of trophic status in the single reservoir ecosystem. Based on monthly monitoring data of chlorophyll a, transparency, nutrients, and nonvolatile suspended solids (NVSS) during 1-year period, the present study evaluated temporal coherence to test whether local-scale regulators disturb the seasonal dynamics of trophic state indices (TSI) in a giant dendritic reservoir, China (Three Gorges Reservoir, TGR). Reservoir-wide coherences for TSI(CHL), TSI(SD), and TSI(TP) showed dramatic variations over spatial scale, indicating temporal asynchrony of trophic status. Following the concept of TSI differences, algal productivity in the mainstream of TGR and Xiangxi Bay except the upstream of the bay were always limited by nonalgal turbidity (TSI(CHL)-TSI(SD) TSI(CHL)-TSI(TN) TSI(CHL)-TSI(TP) TSI differences showed that local processes of Xiangxi Bay were the main responsible for local asynchrony of nonalgal turbidity limitation levels. Regression analysis further proved that local temporal asynchrony for TSI(SD) and nonalgal turbidity limitation levels were regulated by local dynamics of NVSS, rather than geographical distance. The implications of the present study are to emphasize that the results of trophic status obtained from a single environment (reservoir mainstream) cannot be extrapolated to other environments (tributary bay) in a way that would allow its use as a sentinel site.

  7. Gas coning control for smart wells using a dynamic coupled well-reservoir simulator

    NARCIS (Netherlands)

    Leemhuis, A.P.; Nennie, E.D.; Belfroid, S.P.C.; Alberts, G.J.N.; Peters, E.; Joosten, G.J.P.


    A strong increase in gas inflow due to gas coning and the resulting bean-back because of Gas to Oil Ratio (GOR) constraints can severely limit oil production and reservoir drive energy. In this paper we will use a coupled reservoir-well model to demonstrate that oil production can be increased by

  8. Reservoir-induced seismicity at Castanhao reservoir, NE Brazil (United States)

    Nunes, B.; do Nascimento, A.; Ferreira, J.; Bezerra, F.


    Our case study - the Castanhão reservoir - is located in NE Brazil on crystalline rock at the Borborema Province. The Borborema Province is a major Proterozoic-Archean terrain formed as a consequence of convergence and collision of the São Luis-West Africa craton and the São Francisco-Congo-Kasai cratons. This reservoir is a 60 m high earth-filled dam, which can store up to 4.5 billion m3 of water. The construction begun in 1990 and finished in October 2003.The first identified reservoir-induced events occurred in 2003, when the water level was still low. The water reached the spillway for the first time in January 2004 and, after that, an increase in seismicity occured. The present study shows the results of a campaign done in the period from November 19th, 2009 to December 31th, 2010 at the Castanhão reservoir. We deployed six three-component digital seismographic station network around one of the areas of the reservoir. We analyzed a total of 77 events which were recorded in at least four stations. To determine hypocenters and time origin, we used HYPO71 program (Lee & Lahr, 1975) assuming a half-space model with following parameters: VP= 5.95 km/s and VP/VS=1.73. We also performed a relocation of these events using HYPODD (Waldhauser & Ellsworth, 2000) programme. The input data used we used were catalogue data, with all absolute times. The results from the spatio-temporal suggest that different clusters at different areas and depths are triggered at different times due to a mixture of: i - pore pressure increase due to diffusion and ii - increase of pore pressure due to the reservoir load.

  9. Water quality and trend analysis of Colorado--Big Thompson system reservoirs and related conveyances, 1969 through 2000 (United States)

    Stevens, Michael R.


    . This report summarizes and assesses: Water-quality and field-measurement profile data collected by the U.S. Geological Survey and stored in the U.S. Geological Survey National Water Information System, Time-series trends of chemical constituents and physical properties, Trends in oxygen deficits in the hypolimnion of the reservoirs in the late summer season by the seasonal Kendall trend test method, Nutrient limitation and trophic status indicators, and Water-quality data in terms of Colorado water-quality standards. Water quality was generally acceptable for primary uses throughout the Colorado?Big Thompson system over the site periods of record, which are all within the span of 1969 to 2000. Dissolved solids and nutrient concentrations were low and typical of a forested/mountainous/crystalline bedrock hydrologic setting. Most of the more toxic trace elements were rarely detected or were found in low concentrations, due at least in part to a relative lack of ore-mineral deposits within the drainage areas of the Colorado?Big Thompson Project. Constituent concentrations consistently met water-quality standard thresholds set by the State of Colorado. Trophic-State Index Values indicated mesotrophic conditions generally prevailed at reservoirs, based on available Secchi depth, total phosphorus concentrations, and chlorophyll-a concentrations. Based on plots of time-series values and concentrations and seasonal Kendall nonparametric trends testing, dissolved solids and most major ions are decreasing at most sites. Many of the nutrient data did not meet the minimum criteria for time-series testing; but for those that did, nutrient concentrations were generally stable (no statistical trend) or decreasing (ammonia plus organic nitrogen and total phosphorus). Iron and manganese concentrations were stable or decreasing at most sites that met testing criteria. Chlorophyll-a data were only collected for 11 years but generally indicated quasi-stable or d

  10. Performance of one of the Iranian carbonate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Jamshidnezhad, M. [National Iranian Oil Co. (Iran, Islamic Republic of)


    The performance of a horizontal well in a carbonate petroleum reservoir in Iran was described following an analysis of of an Iranian carbonate field located in southern Iran. The field is 23 km long, 7 km wide and contains 2 reservoirs, one of which sits over the other. An impermeable zone separates the 2 reservoirs. Both horizontal and directional drilling technologies have been used to develop the field. Production began a decade ago and is expected to continue for another 80 years. Currently, there are 28 wells, of which 6 are horizontal and 7 are directional. There are several problems regarding horizontal wells in the carbonate reservoirs of Iran. These include the loss of drilling mud, difficulty in petrophysical logging, and high costs. This study included a geological examination of PVT, static pressure, well testing, and experimental performance of horizontal, vertical and directional wells to determine the overall performance of the field. The objective was to find ways to increase the rate of production. It was determined that wells should be drilled vertically as much as possible, particularly in the second reservoir. Horizontal drilling technology should be used a last resort and only in the first reservoir. The author also recommends the use of an artificial lift involving electrical submersible pumps. 1 ref., 4 tabs., 10 figs.

  11. Antibiotic resistance reservoirs

    NARCIS (Netherlands)

    Versluis, Dennis


    One of the major threats to human health in the 21st century is the emergence of pathogenic bacteria that are resistant to multiple antibiotics, thereby limiting treatment options. An important route through which pathogens become resistant is via acquisition of resistance genes from environmental

  12. Antibiotic resistance reservoirs

    NARCIS (Netherlands)

    Versluis, Dennis


    One of the major threats to human health in the 21st century is the emergence of pathogenic bacteria that are resistant to multiple antibiotics, thereby limiting treatment options. An important route through which pathogens become resistant is via acquisition of resistance genes from

  13. A method for improving predictions of bed-load discharges to reservoirs (United States)

    Lopes, V.L.; Osterkamp, W.R.; Bravo-Espinosa, M.


    Effective management options for mitigating the loss of reservoir water storage capacity to sedimentation depend on improved predictions of bed-load discharges into the reservoirs. Most predictions of bed-load discharges, however, are based on the assumption that the rates of bed-load sediment availability equal the transport capacity of the flow, ignoring the spatio-temporal variability of the sediment supply. This paper develops a semiquantitative method to characterize bed-load sediment transport in alluvial channels, assuming a channel reach is non-supply limited when the bed-load discharge of a given sediment particle-size class is functionally related to the energy that is available to transport that fraction of the total bed-load. The method was applied to 22 alluvial stream channels in the USA to determine whether a channel reach had a supply-limited or non-supply-limited bed-load transport regime. The non-supply-limited transport regime was further subdivided into two groups on the basis of statistical tests. The results indicated the pattern of bed-load sediment transport in alluvial channels depends on the complete spectrum of sediment particle sizes available for transport rather than individual particle-size fractions represented by one characteristic particle size. The application of the method developed in this paper should assist reservoir managers in selecting bed-load sediment transport equations to improve predictions of bed-load discharge in alluvial streams, thereby significantly increasing the efficiency of management options for maintaining the storage capacity of waterbodies. ?? 2007 Blackwell Publishing Asia Pty Ltd.

  14. The Stimulation of Hydrocarbon Reservoirs with Subsurface Nuclear Explosions

    Energy Technology Data Exchange (ETDEWEB)



    Between 1965 and 1979 there were five documented and one or more inferred attempts to stimulate the production from hydrocarbon reservoirs by detonating nuclear devices in reservoir strata. Of the five documented tests, three were carried out by the US in low-permeability, natural-gas bearing, sandstone-shale formations, and two were done in the USSR within oil-bearing carbonates. The objectives of the US stimulation efforts were to increase porosity and permeability in a reservoir around a specific well by creating a chimney of rock rubble with fractures extending beyond it, and to connect superimposed reservoir layers. In the USSR, the intent was to extensively fracture an existing reservoir in the more general vicinity of producing wells, again increasing overall permeability and porosity. In both countries, the ultimate goals were to increase production rates and ultimate recovery from the reservoirs. Subsurface explosive devices ranging from 2.3 to about 100 kilotons were used at depths ranging from 1208 m (3963 ft) to 2568 m (8427 ft). Post-shot problems were encountered, including smaller-than-calculated fracture zones, formation damage, radioactivity of the product, and dilution of the BTU value of tie natural gas with inflammable gases created by the explosion. Reports also suggest that production-enhancement factors from these tests fell short of expectations. Ultimately, the enhanced-production benefits of the tests were insufficient to support continuation of the pro-grams within increasingly adversarial political, economic, and social climates, and attempts to stimulate hydrocarbon reservoirs with nuclear devices have been terminated in both countries.

  15. Defining and Applying Limits for Test and Flight Through the Project Lifecycle GSFC Standard. [Scope: Non-Cryogenic Systems Tested in Vacuum (United States)

    Mosier, Carol


    The presentation will be given at the Annual Thermal Fluids Analysis Workshop (TFAWS 2015, NCTS 21070-15) hosted by the Goddard SpaceFlight Center (GSFC) Thermal Engineering Branch (Code 545). The powerpoint presentation details the process of defining limits throughout the lifecycle of a flight project.

  16. Reservoir system optimisation using a penalty approach and a multi ...

    African Journals Online (AJOL)

    ... IV obtained several high-performance solutions of varied sizes and supply capabilities. This analysis revealed specific limitations of supply reliability and the expected storage states of one of the reservoirs. The analysis also obtained the ranges within which the optimal monthly operating rules for the system are expected.

  17. Impact of fault damage zones on reservoir performance in the Hibernia oilfield (Jeanne d'Arc Basin, Newfoundland) : an analysis of structural, petrophysical and dynamic well-test data

    Energy Technology Data Exchange (ETDEWEB)

    Porter, J.R.; McAllister, E.; Fisher, Q.J.; Knipe, R.J.; Condliffe, D.M.; Kay, M.A. [Leeds Univ., Leeds (United Kingdom). Dept. of Earth Sciences, Rock Deformation Research Group; Stylianides, G.; Sinclair, I.K. [Hibernia Management and Development Co. Ltd., St. John' s, NL (Canada)


    Petroleum reservoirs are typically characterized by combining conventional core analysis results, wire-line log data and sedimentological description with production data. This study emphasized the benefits of including structural analysis of core material as part of general reservoir characterization. In particular, it examined the influence of fault zones on fluid flow within the Hibernia Formation in the Hibernia Oilfield in the Jeanne d'Arc Basin on the Grand Banks of Newfoundland. The geologic setting and background to the Hibernia Field was presented. Fault seal analysis was used in the study to help manage the compartmentalized Hibernia Field. Cross-fault juxtaposition analysis was also integrated with structural logging and petrophysical measurement of core material. The analysis of core material resulted in an increased confidence in production data interpretation. The study also examined how deformation features present within the Hibernia Formation drill cores have the potential to act as baffles or seals to hydrocarbon flow. Deformation features were described with reference to low, intermediate and high clay content fault rocks. It was shown that fault rocks are capable of severely restricting fluid flow, particularly when close to production or injection wells. The targeting of wheels to avoid the damage-zone envelope associated with seismic-scale faults will result in a large improvement in producer-injector performance despite reducing the potential drainage volume. The results confirm that inclusion of structural analysis in reservoir characterization studies can have a great and positive impact on field management strategies. 31 refs., 2 tabs., 8 figs.

  18. Introduction to the appropriate-stimulation degree of hydraulic fracture networks in shale gas reservoirs

    Directory of Open Access Journals (Sweden)

    Yuzhang Liu


    Full Text Available Due to the limitation of actual shale gas reservoir conditions and fracturing technologies, artificial fracture networks are different greatly even in the same or similar stimulated reservoir volume. Deviations and even faults occur in evaluation and cognition if only the stimulated reservoir volume (SRV is used to characterize and evaluate the effect of stimulation. In this paper, the spatial distribution of artificial fractures and natural fractures and the internal pressure state and degree of reserve recovery of stimulated shale gas reservoirs were studied by means of artificial fracture propagation numerical simulation and production numerical simulation. And three concepts were proposed, i.e., shale gas fracture network, ideal fracture network and appropriate-stimulation degree of fracture network. The study results indicate that, at the end of reservoir development, target zones can be classified into three types (i.e., relatively appropriate stimulation zone, transitional stimulation zone, and uncompleted stimulation zone according to the recovery degree and production time of stimulated reservoirs; and that the final morphologic parameter of fracture networks and the reservoir characteristic are two main factors affecting the appropriate-stimulation degree of fracture networks. As for a specific gas reservoir, the orientation, length, conduction, height and spatial location of its fracture network are the main factors influencing its appropriate-stimulation degree if the well trajectory is set. The proposal of the theory on the appropriate-stimulation degree of hydraulic fracture networks in shale gas reservoir enriches the theoretical system of shale reservoir stimulation technology, and it can be used as the reference for characterizing the fracture systems in other unconventional reservoirs, such as tight oil and gas reservoirs. Keywords: Shale gas, Reservoir stimulation, Ideal fracture network, Appropriate-stimulation degree of

  19. Application of Integrated Reservoir Management and Reservoir Characterization to Optimize Infill Drilling

    Energy Technology Data Exchange (ETDEWEB)



    Infill drilling if wells on a uniform spacing without regard to reservoir performance and characterization foes not optimize reservoir development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. New and emerging technologies, such as geostatistical modeling, rigorous decline curve analysis, reservoir rock typing, and special core analysis can be used to develop a 3-D simulation model for prediction of infill locations.

  20. Cloud computing and Reservoir project

    International Nuclear Information System (INIS)

    Beco, S.; Maraschini, A.; Pacini, F.; Biran, O.


    The support for complex services delivery is becoming a key point in current internet technology. Current trends in internet applications are characterized by on demand delivery of ever growing amounts of content. The future internet of services will have to deliver content intensive applications to users with quality of service and security guarantees. This paper describes the Reservoir project and the challenge of a reliable and effective delivery of services as utilities in a commercial scenario. It starts by analyzing the needs of a future infrastructure provider and introducing the key concept of a service oriented architecture that combines virtualisation-aware grid with grid-aware virtualisation, while being driven by business service management. This article will then focus on the benefits and the innovations derived from the Reservoir approach. Eventually, a high level view of Reservoir general architecture is illustrated.

  1. False negative HIV antibody test in HIV infected children who receive early antiretroviral treatment in a resource-limited setting

    Directory of Open Access Journals (Sweden)

    Gerardo Alvarez-Uria


    Full Text Available With the implementation of 2010 World Health Organization guidelines, the number of infants from developing countries who will initiate antiretroviral therapy (ART will increase considerably. In this study we describe the HIV antibody tests of 14 HIV infected children who initiated ART at age less than one year in a rural setting of India. The HIV rapid test was negative in seven and indeterminate in two cases, whereas the HIV enzyme-linked immunosorbent assay (ELISA antibody test was negative in three and indeterminate in one case. In one child who had both negative HIV rapid test and ELISA initially, HIV serology turned positive after having a virological failure to ART, suggesting the possibility of utilizing HIV serology for monitoring ART effectiveness in children who experience HIV seroreversion. In conclusion, HIV seroreversion of children with early initiation of ART is common and should be considered for avoiding misdiagnosis of HIV infection. 

  2. [Combined pulmonary fibrosis and emphysema (CPFE)--limitation of usual lung function test and challenge at practice]. (United States)

    Takai, Daiya


    Spirometry and the flow-volume curve test are commonly performed lung function tests. However, a unique clinical entity occasionally shows almost normal data in these tests, and is therefore missed on screening tests. The clinical entity of combined pulmonary emphysema and pulmdoary fibrosis was recognized and documented in the 90's in Japan, the USA, and Europe. Typical emphysema shows obstructive disorders, and pulmonary fibrosis shows restrictive disorders. Thus, the combination of both should lead to a combined disorder pattern in lung function tests, but this is not the case. In 2005, Cottin reported and redefined this combination of emphysema and fibrosis of the lung as "Combined Pulmonary Fibrosis and Emphysema" (CPFE). The patients are typically heavily smoking males who show an almost normal lung function. The upper lobe of these patients usually shows severe emphysema, which contributes to a static volume and a late phase in the forced volume test. On the other hand their lower lobe shows fibrotic change. The fibrotic portion contributes to early phase flow in the flow-volume curve. These mechanisms are a reason for the normal pattern appearance in lung function tests in CPFE patients. As a matter of course, these patients have damaged upper and lower lobes: their diffusing capacity of the lung shows a low performance, their saturation of blood hemoglobin decreases soon after light exercise, and their KL-6 (a blood marker of pulmonary fibrosis) usually shows a high value. They are considered a high risk group regarding complications of post-surgical treatment. Thus, when medical technologists identify suspicious cases, they should advise doctors to add diffusing capacity and KL-6 tests. (Review).

  3. Limitations of the QuantiFERON-TB Gold test in detecting Mycobacterium tuberculosis infection in immunocompromised patients

    DEFF Research Database (Denmark)

    Hornum, Mads; Mortensen, Klaus Leth; Kamper, Anne-Lise


    Four cases are presented, immunosuppressed by at least three different mechanisms: one HIV-positive patient with a CD4 count of 0.29 x 10(6)/ml, one malnourished patient, and two kidney-transplanted patients. All patients had a negative interferon (IFN)-gamma test for suspected tuberculosis (TB......), but a positive culture. We conclude that a negative IFN-gamma test does not exclude TB disease in immunosuppressed patients....

  4. Reservoir effects in radiocarbon dating

    International Nuclear Information System (INIS)

    Head, M.J.


    Full text: The radiocarbon dating technique depends essentially on the assumption that atmospheric carbon dioxide containing the cosmogenic radioisotope 14 C enters into a state of equilibrium with all living material (plants and animals) as part of the terrestrial carbon cycle. Terrestrial reservoir effects occur when the atmospheric 14 C signal is diluted by local effects where systems depleted in 14 C mix with systems that are in equilibrium with the atmosphere. Naturally, this can occur with plant material growing close to an active volcano adding very old CO 2 to the atmosphere (the original 14 C has completely decayed). It can also occur in highly industrialised areas where fossil fuel derived CO 2 dilutes the atmospheric signal. A terrestrial reservoir effect can occur in the case of fresh water shells living in rivers or lakes where there is an input of ground water from springs or a raising of the water table. Soluble bicarbonate derived from the dissolution of very old limestone produces a 14 C dilution effect. Land snail shells and stream carbonate depositions (tufas and travertines) can be affected by a similar mechanism. Alternatively, in specific cases, these reservoir effects may not occur. This means that general interpretations assuming quantitative values for these terrestrial effects are not possible. Each microenvironment associated with samples being analysed needs to be evaluated independently. Similarly, the marine environment produces reservoir effects. With respect to marine shells and corals, the water depth at which carbonate growth occurs can significantly affect quantitative 14 C dilution, especially in areas where very old water is uplifted, mixing with top layers of water that undergo significant exchange with atmospheric CO 2 . Hence, generalisations with respect to the marine reservoir effect also pose problems. These can be exacerbated by the mixing of sea water with either terrestrial water in estuaries, or ground water where

  5. Understanding the Role of Reservoir Size on Probable Maximum Precipitation (United States)

    Woldemichael, A. T.; Hossain, F.


    This study addresses the question 'Does surface area of an artificial reservoir matter in the estimation of probable maximum precipitation (PMP) for an impounded basin?' The motivation of the study was based on the notion that the stationarity assumption that is implicit in the PMP for dam design can be undermined in the post-dam era due to an enhancement of extreme precipitation patterns by an artificial reservoir. In addition, the study lays the foundation for use of regional atmospheric models as one way to perform life cycle assessment for planned or existing dams to formulate best management practices. The American River Watershed (ARW) with the Folsom dam at the confluence of the American River was selected as the study region and the Dec-Jan 1996-97 storm event was selected for the study period. The numerical atmospheric model used for the study was the Regional Atmospheric Modeling System (RAMS). First, the numerical modeling system, RAMS, was calibrated and validated with selected station and spatially interpolated precipitation data. Best combinations of parameterization schemes in RAMS were accordingly selected. Second, to mimic the standard method of PMP estimation by moisture maximization technique, relative humidity terms in the model were raised to 100% from ground up to the 500mb level. The obtained model-based maximum 72-hr precipitation values were named extreme precipitation (EP) as a distinction from the PMPs obtained by the standard methods. Third, six hypothetical reservoir size scenarios ranging from no-dam (all-dry) to the reservoir submerging half of basin were established to test the influence of reservoir size variation on EP. For the case of the ARW, our study clearly demonstrated that the assumption of stationarity that is implicit the traditional estimation of PMP can be rendered invalid to a large part due to the very presence of the artificial reservoir. Cloud tracking procedures performed on the basin also give indication of the

  6. Sedimentological and Geomorphological Effects of Reservoir Flushing: The Cachi Reservoir, Costa Rica, 1996

    DEFF Research Database (Denmark)

    Brandt, Anders; Swenning, Joar


    Physical geography, hydrology, geomorphology, sediment transport, erosion, sedimentation, dams, reservoirs......Physical geography, hydrology, geomorphology, sediment transport, erosion, sedimentation, dams, reservoirs...

  7. Application of Integrated Reservoir Management and Reservoir Characterization to Optimize Infill Drilling

    Energy Technology Data Exchange (ETDEWEB)

    P. K. Pande


    Initial drilling of wells on a uniform spacing, without regard to reservoir performance and characterization, must become a process of the past. Such efforts do not optimize reservoir development as they fail to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. These reservoirs are typically characterized by: o Large, discontinuous pay intervals o Vertical and lateral changes in reservoir properties o Low reservoir energy o High residual oil saturation o Low recovery efficiency

  8. A method for reducing model error while interpreting pressure derivative in well test analysis : application to Hassi Messaoud Algerian oil field

    Energy Technology Data Exchange (ETDEWEB)

    Bachar, S. [PED/AMT/Sonatrach Inc., Alger (Algeria); Deghmoum, A.H. [CRD/AMT/Sonatrach Inc., Alger (Algeria); Tiab, D. [Oklahoma Univ., Norman, OK (United States)


    A new method for reducing well test model error was presented. Improvements in exploiting the shape and the particular points of a pressure derivative curve have led to significant progress in reservoir characterization and development. The quality of measured pressure data can be affected by external or internal noise, resulting in amplified errors in computing pressure derivatives. The noise can also result in unreliable data of wellbore storage, flow regimes, reservoir permeability, and boundary limits. This newly developed model adjusts the derivative pressure in cases of vertical and horizontal wells, homogenous composite reservoirs, or naturally fractured reservoirs. It also includes buildup or drawdown tests. The numerical model is based on Tiab's Direct Synthesis method and is adapted to the Golub method. The paper presents case studies where the method has been applied to the Hassi Messaoud Algerian oil reservoir. 20 refs., 3 tabs., 8 figs.


    Directory of Open Access Journals (Sweden)

    Daniel Constantin DIACONU


    Full Text Available Siriu reservoir, owes it`s creation to the dam built on the river Buzau, in the town which bears the same name. The reservoir has a hydro energetic role, to diminish the maximum flow and to provide water to the localities below. The partial exploitation of the lake, began in 1984; Since that time, the initial bed of the river began to accumulate large quantities of alluvia, reducing the retention capacity of the lake, which had a volume of 125 million m3. The changes produced are determined by many topographic surveys at the bottom of the lake.

  10. Climate Change Assessment of Precipitation in Tandula Reservoir System (United States)

    Jaiswal, Rahul Kumar; Tiwari, H. L.; Lohani, A. K.


    The precipitation is the principle input of hydrological cycle affect availability of water in spatial and temporal scale of basin due to widely accepted climate change. The present study deals with the statistical downscaling using Statistical Down Scaling Model for rainfall of five rain gauge stations (Ambagarh, Bhanpura, Balod, Chamra and Gondli) in Tandula, Kharkhara and Gondli reservoirs of Chhattisgarh state of India to forecast future rainfall in three different periods under SRES A1B and A2 climatic forcing conditions. In the analysis, twenty-six climatic variables obtained from National Centers for Environmental Prediction were used and statistically tested for selection of best-fit predictors. The conditional process based statistical correlation was used to evolve multiple linear relations in calibration for period of 1981-1995 was tested with independent data of 1996-2003 for validation. The developed relations were further used to predict future rainfall scenarios for three different periods 2020-2035 (FP-1), 2046-2064 (FP-2) and 2081-2100 (FP-3) and compared with monthly rainfalls during base period (1981-2003) for individual station and all three reservoir catchments. From the analysis, it has been found that most of the rain gauge stations and all three reservoir catchments may receive significant less rainfall in future. The Thiessen polygon based annual and seasonal rainfall for different catchments confirmed a reduction of seasonal rainfall from 5.1 to 14.1% in Tandula reservoir, 11-19.2% in Kharkhara reservoir and 15.1-23.8% in Gondli reservoir. The Gondli reservoir may be affected the most in term of water availability in future prediction periods.

  11. Thermoelastic properties of the Rotokawa Andesite: A geothermal reservoir constraint (United States)

    Siratovich, P. A.; von Aulock, F. W.; Lavallée, Y.; Cole, J. W.; Kennedy, B. M.; Villeneuve, M. C.


    Knowledge of the thermal properties of geothermal reservoir rocks is essential to constraining important engineering concerns such as wellbore stability, reservoir forecasting and stimulation procedures. The thermo-mechanical evolution of geological material is also important to assess when considering natural processes such as magmatic dyke propagation, contact metamorphism and magma/lava emplacement and cooling effects. To better constrain these properties in the geothermal reservoir, thermal measurements were carried out on core samples from production wells drilled in the Rotokawa Andesite geothermal reservoir, located in the Taupo Volcanic Zone, New Zealand. Linear thermal expansion testing, thermogravimetric analysis, and differential scanning calorimetry were used, employing experimental heating rates of 2, 5 and 20 °C/min. Thermal property analyses can elucidate whether thermal expansion values measured under varied heating (and cooling) rates are rate dependent and if thermo-chemical reactions influence the resultant expansivity. Measured thermal expansion coefficients of the Rotokawa Andesite are shown not to be heating rate dependent. We have also found that significant thermochemical reactions occur during heating above 500 °C resulting in non-reversible changes to the thermomechanical properties. The combined thermogravimetric, calorimetric and thermomechanical analysis allows insight to the reactions occurring and how the thermomechanical properties are affected at high temperature. We incorporated results of tensile strength testing on the Rotokawa Andesite to apply our thermal property measurements to a one-dimensional thermal stress model. The developed model provides a failure criterion for the Rotokawa Andesite under thermal stress. The importance of this study is to further understand the critical heating and cooling rates at which thermal stress may cause cracking within the Rotokawa reservoir. Thermal cracking in the reservoir can be

  12. Drought and reservoirs: intended benefits and unintended consequences (United States)

    Di Baldassarre, Giuliano; AghaKouchak, Amir; Rangecroft, Sally; Wanders, Niko; Kuil, Linda; Veldkamp, Ted; van Loon, Anne


    Socioeconomic drought can be broadly defined as a condition whereby water demand cannot be satisfied by water supply. Here we posit that while reservoirs often alleviate socioeconomic drought, they can lead to unintended consequences in the medium-long term. Losses caused by socioeconomic drought tend to trigger public pressure for action, which can result in the introduction or expansion of reservoirs to store more water during high flow conditions, and release it during low flow conditions. In the short term, increasing reservoir storage is often beneficial because frequency, magnitude, and duration of drought can be significantly reduced. Yet, it is important to note that reservoirs may fail in mitigating major, prolonged drought, because reservoir storage is unavoidably limited. In the medium-long term, two main dynamics tend to emerge, which often generate unintended consequences. The first one, termed here as "supply-demand cycle", is when increasing water supply triggers additional development and thus generates higher demand, which then offsets the benefit of reservoirs as a water supply source. This is a self-reinforcing feedback, or vicious cycle, as the occurrence of a new socioeconomic drought will then likely trigger further expansion of reservoir storage to, again, increase water supply. A second dynamic, termed here as "reservoir effect" (after White's "levee effect"), is when extended periods of abundant water supply, secured by reservoirs, generate a decline of coping capacities through increased competition for water and reduced shocks to the system, which in turn increases the vulnerability of the system to socio-economic drought. In other words, while a frequent experience of water shortages can help keep high levels of preparedness, some elements of system's resilience can be lost when minor-to-moderate events are avoided. As a result, the development of reservoirs can generate a shift from frequent socioeconomic drought conditions to rare

  13. Technical principles underlying limit values for release of substances for the percolation test TS3: comparison DE and NL

    Energy Technology Data Exchange (ETDEWEB)

    Van Zomeren, A.; Dijkstra, J.J. [ECN Environment and Energy Engineering, Petten (Netherlands); Susset, B. [Consulting Office SiWaP (Germany)


    Within CEN TC 351 WG 1, standardized, horizontal test methods are developed to assess the release (leaching) of dangerous substances from construction as defined in ER3 of the CPD. For granular materials TS 3, a horizontal up-flow percolation test, was further developed by CEN TC 351 WG1 and will enter the validation phase in 2013. In CEN TC 351 WG1, there are still discussions regarding the sample preparation and some test conditions. Currently, two options for sample preparation and test conditions are specified. Controversy between DE and NL regarding sample preparation and test conditions and the need for two separate options in the TS 3 percolation test are possibly for a part caused by different approaches for risk assessment in the Netherlands and in Germany and the resulting regulatory concepts. One important reason for this is, that in soil and groundwater regulations the test method and the impact assessment method are systematically linked together but the impact assessment methods and lab methods in both countries are different. The discussions in CEN TC 351 WG 1 show that there is a need to have a better mutual understanding of the relation between test method and impact assessment on the one hand and a clear overview of differences in impact assessment approaches of each country on the other hand. The aim of this project is to explain and compare the assumptions, boundary conditions and conventions of the impact assessment approach that are implemented in the upcoming German Recycling Degree and in the Soil Quality Degree of the Netherlands. Ultimately, a better understanding of the impact assessment approaches provides a basis for further discussion in WG1 to agree on only one option for the percolation test conditions. The following report is prepared by the contractors of Germany and Netherlands together to compare the two country-specific concepts. This report summarizes and explains the presentation given on the 25th of April at TC 351 WG1 in

  14. Evaluation of walking speed tests as a measurement of functional limitations in elderly people: A structured review

    Directory of Open Access Journals (Sweden)

    Carmen L. Muñoz-Mendoza


    Full Text Available El objetivo de este estudio teórico fue valorar el modelo conceptual, la carga, la interpretabilidad, los efectos suelo y techo, la fiabilidad, la validez y la sensibilidad al cambio de los tests de velocidad de andar como medida de limitaciones funcionales en personas mayores. Se realizaron búsquedas electrónicas en Medline, AgeLine, Embase, CINAHL e IME, búsquedas manuales y por referencias. La calidad de las propiedades de medición fue evaluada mediante criterios estandarizados. Se analizaron 102 estudios que identificaron 18 tests. Los tests más utilizados fueron: 2.44 metros, 4 metros y 6 metros, realizados a velocidad del paso habitual. Las evidencias se centraron en la validez predictiva y en la fiabilidad test-retest; en este caso, los valores de los coeficientes fueron superiores a los estándares de calidad recomendados. La interpretabilidad, los efectos suelo y techo y la sensibilidad al cambio son los atributos con menos evidencias. En estudios epidemiológicos, la evidencia disponible apoya el uso de los tests de andar como predictores de resultados adversos relacionados con la salud en personas mayores. Se precisa de estudios que apoyen su viabilidad y aplicabilidad en la práctica clínica, ya sea con la finalidad de screening como para la monitorización y evaluación del cambio.

  15. Comparative analysis of measures of viral reservoirs in HIV-1 eradication studies.

    Directory of Open Access Journals (Sweden)

    Susanne Eriksson


    Full Text Available HIV-1 reservoirs preclude virus eradication in patients receiving highly active antiretroviral therapy (HAART. The best characterized reservoir is a small, difficult-to-quantify pool of resting memory CD4(+ T cells carrying latent but replication-competent viral genomes. Because strategies targeting this latent reservoir are now being tested in clinical trials, well-validated high-throughput assays that quantify this reservoir are urgently needed. Here we compare eleven different approaches for quantitating persistent HIV-1 in 30 patients on HAART, using the original viral outgrowth assay for resting CD4(+ T cells carrying inducible, replication-competent viral genomes as a standard for comparison. PCR-based assays for cells containing HIV-1 DNA gave infected cell frequencies at least 2 logs higher than the viral outgrowth assay, even in subjects who started HAART during acute/early infection. This difference may reflect defective viral genomes. The ratio of infected cell frequencies determined by viral outgrowth and PCR-based assays varied dramatically between patients. Although strong correlations with the viral outgrowth assay could not be formally excluded for most assays, correlations achieved statistical significance only for integrated HIV-1 DNA in peripheral blood mononuclear cells and HIV-1 RNA/DNA ratio in rectal CD4(+ T cells. Residual viremia was below the limit of detection in many subjects and did not correlate with the viral outgrowth assays. The dramatic differences in infected cell frequencies and the lack of a precise correlation between culture and PCR-based assays raise the possibility that the successful clearance of latently infected cells may be masked by a larger and variable pool of cells with defective proviruses. These defective proviruses are detected by PCR but may not be affected by reactivation strategies and may not require eradication to accomplish an effective cure. A molecular understanding of the discrepancy

  16. Enhanced characterization of reservoir hydrocarbon components using electromagnetic data attributes

    KAUST Repository

    Katterbauer, Klemens


    Advances in electromagnetic imaging techniques have led to the growing utilization of this technology for reservoir monitoring and exploration. These exploit the strong conductivity contrast between the hydrocarbon and water phases and have been used for mapping water front propagation in hydrocarbon reservoirs and enhancing the characterization of the reservoir formation. The conventional approach for the integration of electromagnetic data is to invert the data for saturation properties and then subsequently use the inverted properties as constraints in the history matching process. The non-uniqueness and measurement errors may however make this electromagnetic inversion problem strongly ill-posed, leading to potentially inaccurate saturation profiles. Another limitation of this approach is the uncertainty of Archie\\'s parameters in relating rock conductivity to water saturation, which may vary in the reservoir and are generally poorly known. We present an Ensemble Kalman Filter framework for efficiently integrating electromagnetic data into the history matching process and for simultaneously estimating the Archie\\'s parameters and the variance of the observation error of the electromagnetic data. We apply the proposed framework to a compositional reservoir model. We aim at assessing the relevance of EM data for estimating the different hydrocarbon components of the reservoir. The experimental results demonstrate that the individual hydrocarbon components are generally well matched, with nitrogen exhibiting the strongest improvement. The estimated observation error standard deviations are also within expected levels (between 5 and 10%), significantly contributing to the robustness of the proposed EM history matching framework. Archie\\'s parameter estimates approximate well the reference profile and assist in the accurate description of the electrical conductivity properties of the reservoir formation, hence leading to estimation accuracy improvements of around

  17. Synergizing Crosswell Seismic and Electromagnetic Techniques for Enhancing Reservoir Characterization

    KAUST Repository

    Katterbauer, Klemens


    Increasing complexity of hydrocarbon projects and the request for higher recovery rates have driven the oil-and-gas industry to look for a more-detailed understanding of the subsurface formation to optimize recovery of oil and profitability. Despite the significant successes of geophysical techniques in determining changes within the reservoir, the benefits from individually mapping the information are limited. Although seismic techniques have been the main approach for imaging the subsurface, the weak density contrast between water and oil has made electromagnetic (EM) technology an attractive complement to improve fluid distinction, especially for high-saline water. This crosswell technology assumes greater importance for obtaining higher-resolution images of the interwell regions to more accurately characterize the reservoir and track fluid-front developments. In this study, an ensemble-Kalman-based history-matching framework is proposed for directly incorporating crosswell time-lapse seismic and EM data into the history-matching process. The direct incorporation of the time-lapse seismic and EM data into the history-matching process exploits the complementarity of these data to enhance subsurface characterization, to incorporate interwell information, and to avoid biases that may be incurred from separate inversions of the geophysical data for attributes. An extensive analysis with 2D and realistic 3D reservoirs illustrates the robustness and enhanced forecastability of critical reservoir variables. The 2D reservoir provides a better understanding of the connection between fluid discrimination and enhanced history matches, and the 3D reservoir demonstrates its applicability to a realistic reservoir. History-matching enhancements (in terms of reduction in the history-matching error) when incorporating both seismic and EM data averaged approximately 50% for the 2D case, and approximately 30% for the 3D case, and permeability estimates were approximately 25

  18. Using microstructure observations to quantify fracture properties and improve reservoir simulations. Final report, September 1998

    Energy Technology Data Exchange (ETDEWEB)

    Laubach, S.E.; Marrett, R.; Rossen, W.; Olson, J.; Lake, L.; Ortega, O.; Gu, Y.; Reed, R.


    The research for this project provides new technology to understand and successfully characterize, predict, and simulate reservoir-scale fractures. Such fractures have worldwide importance because of their influence on successful extraction of resources. The scope of this project includes creation and testing of new methods to measure, interpret, and simulate reservoir fractures that overcome the challenge of inadequate sampling. The key to these methods is the use of microstructures as guides to the attributes of the large fractures that control reservoir behavior. One accomplishment of the project research is a demonstration that these microstructures can be reliably and inexpensively sampled. Specific goals of this project were to: create and test new methods of measuring attributes of reservoir-scale fractures, particularly as fluid conduits, and test the methods on samples from reservoirs; extrapolate structural attributes to the reservoir scale through rigorous mathematical techniques and help build accurate and useful 3-D models of the interwell region; and design new ways to incorporate geological and geophysical information into reservoir simulation and verify the accuracy by comparison with production data. New analytical methods developed in the project are leading to a more realistic characterization of fractured reservoir rocks. Testing diagnostic and predictive approaches was an integral part of the research, and several tests were successfully completed.

  19. A hybrid waveguide cell for the dielectric properties of reservoir rocks

    International Nuclear Information System (INIS)

    Siggins, A F; Gunning, J; Josh, M


    A hybrid waveguide cell is described for broad-band measurements of the dielectric properties of hydrocarbon reservoir rocks. The cell is designed to operate in the radio frequency range of 1 MHz to 1 GHz. The waveguide consists of 50 Ω coaxial lines feeding into a central cylindrical section which contains the sample under test. The central portion of the waveguide acts as a circular waveguide and can accept solid core plugs of 38 mm diameter and lengths from 2 to 150 mm. The central section can also be used as a conventional coaxial waveguide when a central electrode with spring-loaded end collets is installed. In the latter mode the test samples are required to be in the form of hollow cylinders. An additional feature of the cell is that the central section is designed to telescope over a limited range of 1–2 mm with the application of an axial load. Effective pressures up to 35 MPa can be applied to the sample under the condition of uniaxial strain. The theoretical basis of the hybrid waveguide cell is discussed together with calibration results. Two reservoir rocks, a Donnybrook sandstone and a kaolin rich clay, are then tested in the cell, both as hollow cylinders in coaxial mode and in the form of solid core plugs. The complex dielectric properties of the two materials over the bandwidth of 1 MHz to 1 GHz are compared with the results of the two testing methods

  20. Biodiesel production from sediments of a eutrophic reservoir

    International Nuclear Information System (INIS)

    Kuchkina, A.Yu.; Gladyshev, M.I.; Sushchik, N.N.; Kravchuk, E.S.; Kalachova, G.S.


    Sediments from eutrophic reservoir Bugach (Siberia, Russia) were tested for possibility to produce biodiesel. We supposed that the sediments could be a promising biodiesel producer. The major reason of high price of biodiesel fuel is cost of a raw material. The use of dredging sediments for biodiesel production reduces production costs, because the dredging sediments are by-products which originated during lake restoration actions, and are free of cost raw materials. Lipid content in sediments was 0.24% of dry weight. To assess the potential of from sediments as a substitute of diesel fuel, the properties of the biodiesel such as cetane number, iodine number and heat of combustion were calculated. All of this parameters complied with limits established by EN 14214 and EN 14213 related to biodiesel quality. -- Highlights: → Dredging sediments were considered as a new feedstock for biodiesel production. → Lipid and fatty acid content in the sediments were determined. → Main properties of the biodiesel were calculated basing on fatty acid composition. → The properties well complied with limits established in biodiesel standards.

  1. Current limitations and a path forward to improve testing for the environmental assessment of endocrine active substances

    DEFF Research Database (Denmark)

    Coady, Katherine K.; Biever, Ronald C.; Denslow, Nancy D.

    issue of significant concern to for current EACS screening/testing programs involves resources in regard such as to cost, time, trained personnel, and animal use. This is especially problematic when considering the number of chemicals that some regulatory authorities need to assess. One way to address...

  2. Possibilities and limitations of using historic provenance tests to infer forest species growth responses to climate change (United States)

    Laura P. Leites; Gerald E. Rehfeldt; Andrew P. Robinson; Nicholas L. Crookston; Barry Jaquish


    Under projected changes in global climate, the growth and survival of existing forests will depend on their ability to adjust physiologically in response to environmental change. Quantifying their capacity to adjust and whether the response is species- or population-specific is important to guide forest management strategies. New analyses of historic provenance tests...

  3. Limitations of the QuantiFERON-TB Gold test in detecting Mycobacterium tuberculosis infection in immunocompromised patients

    DEFF Research Database (Denmark)

    Hornum, M.; Mortensen, K.L.; Kamper, Anne-Lise


    Four cases are presented, immunosuppressed by at least three different mechanisms: one HIV-positive patient with a CD4 count of 0.29 x 10(6)/ml, one malnourished patient, and two kidney-transplanted patients. All patients had a negative interferon (IFN)-gamma test for suspected tuberculosis (TB),...

  4. A Test of the Circumvention-of-Limits Hypothesis in Scientific Problem Solving: The Case of Geological Bedrock Mapping (United States)

    Hambrick, David Z.; Libarkin, Julie C.; Petcovic, Heather L.; Baker, Kathleen M.; Elkins, Joe; Callahan, Caitlin N.; Turner, Sheldon P.; Rench, Tara A.; LaDue, Nicole D.


    Sources of individual differences in scientific problem solving were investigated. Participants representing a wide range of experience in geology completed tests of visuospatial ability and geological knowledge, and performed a geological bedrock mapping task, in which they attempted to infer the geological structure of an area in the Tobacco…

  5. Further Validation of Simulated Dynamic Interface Testing Techniques as a Tool in the Forecasting of Air Vehicle Deck Limits (United States)


    and maximize operational flexibility [Healey, 1982]. Globally, DI is concerned with the effects that one free body has in respect to another...Royal Aeronautical Society Conference. London. [3] Bokus, G. and Ferrier, B (1995). Development, Integration and Test of an automatic UAV Recovery Sytem

  6. Reservoir Sedimentation Based on Uncertainty Analysis

    Directory of Open Access Journals (Sweden)

    Farhad Imanshoar


    Full Text Available Reservoir sedimentation can result in loss of much needed reservoir storage capacity, reducing the useful life of dams. Thus, sufficient sediment storage capacity should be provided for the reservoir design stage to ensure that sediment accumulation will not impair the functioning of the reservoir during the useful operational-economic life of the project. However, an important issue to consider when estimating reservoir sedimentation and accumulation is the uncertainty involved in reservoir sedimentation. In this paper, the basic factors influencing the density of sediments deposited in reservoirs are discussed, and uncertainties in reservoir sedimentation have been determined using the Delta method. Further, Kenny Reservoir in the White River Basin in northwestern Colorado was selected to determine the density of deposits in the reservoir and the coefficient of variation. The results of this investigation have indicated that by using the Delta method in the case of Kenny Reservoir, the uncertainty regarding accumulated sediment density, expressed by the coefficient of variation for a period of 50 years of reservoir operation, could be reduced to about 10%. Results of the Delta method suggest an applicable approach for dead storage planning via interfacing with uncertainties associated with reservoir sedimentation.

  7. Stabilization of bottom sediments from Rzeszowski Reservoir

    Directory of Open Access Journals (Sweden)

    Koś Karolina


    Full Text Available The paper presents results of stabilization of bottom sediments from Rzeszowski Reservoir. Based on the geotechnical characteristics of the tested sediments it was stated they do not fulfill all the criteria set for soils in earth embankments. Therefore, an attempt to improve their parameters was made by using two additives – cement and lime. An unconfined compressive strength, shear strength, bearing ratio and pH reaction were determined on samples after different time of curing. Based on the carried out tests it was stated that the obtained values of unconfined compressive strength of sediments stabilized with cement were relatively low and they did not fulfill the requirements set by the Polish standard, which concerns materials in road engineering. In case of lime stabilization it was stated that the tested sediments with 6% addition of the additive can be used for the bottom layers of the improved road base.

  8. HIV Incidence Estimates Using the Limiting Antigen Avidity EIA Assay at Testing Sites in Kiev City, Ukraine: 2013-2014 (United States)

    Kruglov, Yuri; Yurchenko, Alexander


    Objective To estimate HIV incidence and highlight the characteristics of persons at greatest risk of HIV in the Ukraine capital, Kiev. Method Residual samples from newly-diagnosed persons attending the Kiev City AIDS Centre were tested for evidence of recent HIV infection using an avidity assay. Questions on possible risk factors for HIV acquisition and testing history were introduced. All persons (≥16yrs) presenting for an HIV test April’13–March’14 were included. Rates per 100,000 population were calculated using region-specific denominators. Results During the study period 6370 individuals tested for HIV. Of the 467 individuals newly-diagnosed with HIV, 21 had insufficient samples for LAg testing. Of the remaining 446, 39 (8.7%) were classified as recent with an avidity index <1.5ODn, 10 were reclassified as long-standing as their viral load was <1000 copies/mL, resulting in 29 (6.5%) recent HIV infections. The only independent predictor for a recent infection was probable route of exposure, with MSM more likely to present with a recent infection compared with heterosexual contact [Odds Ratio 8.86; 95%CI 2.65–29.60]. We estimated HIV incidence at 21.5 per 100,000 population, corresponding to 466 new infections. Using population estimates for MSM and PWID, incidence was estimated to be between 2289.6 and 6868.7/100,000 MSM, and 350.4 for PWID. Conclusion A high proportion of persons newly-infected remain undiagnosed, with MSM disproportionally affected with one in four newly-HIV-diagnosed and one in three recently-HIV-infected. Our findings should be used for targeted public health interventions and health promotion. PMID:27276170


    Energy Technology Data Exchange (ETDEWEB)

    Mohan Kelkar


    The West Carney Field in Lincoln County, Oklahoma is one of few newly discovered oil fields in Oklahoma. Although profitable, the field exhibits several unusual characteristics. These include decreasing water-oil ratios, decreasing gas-oil ratios, decreasing bottomhole pressures during shut-ins in some wells, and transient behavior for water production in many wells. This report explains the unusual characteristics of West Carney Field based on detailed geological and engineering analyses. We propose a geological history that explains the presence of mobile water and oil in the reservoir. The combination of matrix and fractures in the reservoir explains the reservoir's flow behavior. We confirm our hypothesis by matching observed performance with a simulated model and develop procedures for correlating core data to log data so that the analysis can be extended to other, similar fields where the core coverage may be limited.

  10. Ensemble-Based Data Assimilation in Reservoir Characterization: A Review

    Directory of Open Access Journals (Sweden)

    Seungpil Jung


    Full Text Available This paper presents a review of ensemble-based data assimilation for strongly nonlinear problems on the characterization of heterogeneous reservoirs with different production histories. It concentrates on ensemble Kalman filter (EnKF and ensemble smoother (ES as representative frameworks, discusses their pros and cons, and investigates recent progress to overcome their drawbacks. The typical weaknesses of ensemble-based methods are non-Gaussian parameters, improper prior ensembles and finite population size. Three categorized approaches, to mitigate these limitations, are reviewed with recent accomplishments; improvement of Kalman gains, add-on of transformation functions, and independent evaluation of observed data. The data assimilation in heterogeneous reservoirs, applying the improved ensemble methods, is discussed on predicting unknown dynamic data in reservoir characterization.

  11. Data assimilation in reservoir management

    NARCIS (Netherlands)

    Rommelse, J.R.


    The research presented in this thesis aims at improving computer models that allow simulations of water, oil and gas flows in subsurface petroleum reservoirs. This is done by integrating, or assimilating, measurements into physics-bases models. In recent years petroleum technology has developed

  12. Reservoirs in the United States (United States)

    Harbeck, G. Earl


    Man has engaged in the control of flowing water since history began. Among his early recorded efforts were reservoirs for muncipal water-supplies constructed near ancient Jerusalem to store water which was brought there in masonry conduits. 1/  Irrigation was practiced in Egypt as early as 2000 B. C. There the "basin system" was used from ancient times until the 19th century. The land was divided , into basins of approximately 40,000 acres, separated by earthen dikes. 2/  Flood waters of the Nile generally inundated the basins through canals, many of which were built by the Pharaohs. Even then the economic consequences of a deficient annual flood were recognized. Lake Maeris, which according to Herodotus was an ancient storage reservoir, is said to have had an area of 30,000 acres. In India, the British found at the time of their occupancy of the Presidency of Madras about 50,000 reservoirs for irrigation, many believed to be of ancient construction. 3/ During the period 115-130 A. D. reservoirs were built to improve the water-supply of Athens. Much has been written concerning the elaborate collection and distribution system built to supply Rome, and parts of it remain to this day as monuments to the engineering skill employed by the Romans in solving the problem of large-scale municipal water-supplies.

  13. Reasons for reservoir effect variability

    DEFF Research Database (Denmark)

    Philippsen, Bente


    , aquatic plants and fish from the rivers Alster and Trave range between zero and about 3,000 radiocarbon years. The reservoir age of water DIC depends to a large extent on the origin of the water and is for example correlated with precipitation amounts. These short-term variations are smoothed out in water...

  14. Policy Considerations for Greenhouse Gas Emissions from Freshwater Reservoirs

    Directory of Open Access Journals (Sweden)

    Kirsi Mäkinen


    Full Text Available Emerging concern over greenhouse gas (GHG emissions from wetlands has prompted calls to address the climate impact of dams in climate policy frameworks. Existing studies indicate that reservoirs can be significant sources of emissions, particularly in tropical areas. However, knowledge on the role of dams in overall national emission levels and abatement targets is limited, which is often cited as a key reason for political inaction and delays in formulating appropriate policies. Against this backdrop, this paper discusses the current role of reservoir emissions in existing climate policy frameworks. The distance between a global impact on climate and a need for local mitigation measures creates a challenge for designing appropriate mechanisms to combat reservoir emissions. This paper presents a range of possible policy interventions at different scales that could help address the climate impact of reservoirs. Reservoir emissions need to be treated like other anthropogenic greenhouse gases. A rational treatment of the issue requires applying commonly accepted climate change policy principles as well as promoting participatory water management plans through integrated water resource management frameworks. An independent global body such as the UN system may be called upon to assess scientific information and develop GHG emissions policy at appropriate levels.

  15. Remotely Sensed Monitoring of Small Reservoir Dynamics: A Bayesian Approach

    Directory of Open Access Journals (Sweden)

    Dirk Eilander


    Full Text Available Multipurpose small reservoirs are important for livelihoods in rural semi-arid regions. To manage and plan these reservoirs and to assess their hydrological impact at a river basin scale, it is important to monitor their water storage dynamics. This paper introduces a Bayesian approach for monitoring small reservoirs with radar satellite images. The newly developed growing Bayesian classifier has a high degree of automation, can readily be extended with auxiliary information and reduces the confusion error to the land-water boundary pixels. A case study has been performed in the Upper East Region of Ghana, based on Radarsat-2 data from November 2012 until April 2013. Results show that the growing Bayesian classifier can deal with the spatial and temporal variability in synthetic aperture radar (SAR backscatter intensities from small reservoirs. Due to its ability to incorporate auxiliary information, the algorithm is able to delineate open water from SAR imagery with a low land-water contrast in the case of wind-induced Bragg scattering or limited vegetation on the land surrounding a small reservoir.

  16. Production performance laws of vertical wells by volume fracturing in CBM reservoirs

    Directory of Open Access Journals (Sweden)

    Liehui Zhang


    Full Text Available Volume fracturing technology has been widely applied in the development of coalbed methane (CBM reservoirs. As for the stimulated reservoir volume (SRV created by volume fracturing, the seepage laws of fluids are described more accurately and rationally in the rectangular composite model than in the traditional radial composite model. However, the rectangular composite model considering SRV cannot be solved using the analytical or semi-analytical function method, and its solution from the linear flow model has larger errors. In view of this, SRV areas of CBM reservoirs were described by means of dual-medium model in this paper. The complex CBM migration mechanisms were investigated comprehensively, including adsorption, desorption, diffusion and seepage. A well testing model for rectangular composite fracturing wells in CBM reservoirs based on unsteady-state diffusion was built and solved using the boundary element method combined with Laplace transformation, Stehfest numerical inversion and computer programming technology. Thus, production performance laws of CBM reservoirs were clarified. The flow regimes of typical well testing curves were divided and the effects on change laws of production performance from the boundary size of gas reservoirs, permeability of volume fractured areas, adsorption gas content, reservoir permeability and SRV size were analyzed. Eventually, CBM reservoirs after the volume fracturing stimulation were described more accurately and rationally. This study provides a theoretical basis for a better understanding of the CBM migration laws and an approach to evaluating and developing CBM reservoirs efficiently and rationally.

  17. Nevada Test Site fallout in the area of Enterprise, Utah

    International Nuclear Information System (INIS)

    Krey, P.W.; Hardy, E.P.; Heit, M.


    The analysis of a sediment core from the Enterprise reservoir in southwestern Utah has provided a record of fallout in the area dating to 1945. Assming that all the 137 Cs fallout that occurred at Enterprise reservoir between 1951 and 1957 came exclusively from the Nevada tests, an upper limit of the integrated deposit from this source is 18 mCi/km 2 of 137 Cs decay corrected to 1979 out of a total of 101 measured in 1979. The maximum infinity dose from the external radiation caused by this Nevada Test Site fallout is estimated to be 1700 mrad. This maximum dose is only a factor of two higher than the cumulative estimated dose in Enterprise derived from the radiological surveys conducted after each test. This indicates that the region around Enterprise reservoir did not experience an intrusion of fallout from NTS greatly in excess of what had been deduced from the post-shot external radiation surveys


    Energy Technology Data Exchange (ETDEWEB)

    George Scott III


    Ongoing Phase 2-3 work comprises the final development and field-testing of two complementary real-time reservoir technologies; a stimulation process and a tracer fracturing diagnostic system. Initial DE-FC26-99FT40129 project work included research, development, and testing of the patented gamma tracer fracturing diagnostic system. This process was field-proven to be technically useful in providing tracer measurement of fracture height while fracturing; however, technical licensing restrictions blocked Realtimezone from fully field-testing this real-time gamma diagnostic system, as originally planned. Said restrictions were encountered during Phase 2 field test work as result of licensing limitations and potential conflicts between service companies participating in project work, as related to their gamma tracer logging tool technology. Phase 3 work principally demonstrated field-testing of Realtimezone (RTZ) and NETL's Downhole-mixed Reservoir Stimulation process. Early on, the simplicity of and success of downhole-mixing was evident from well tests, which were made commercially productive. A downhole-mixed acid stimulation process was tested successfully and is currently commercially used in Canada. The fourth well test was aborted due to well bore conditions, and an alternate test project is scheduled April, 2004. Realtimezone continues to effectuate ongoing patent protection in the United States and foreign markets. In 2002, Realtimezone and the NETL licensed their United States patent to Halliburton Energy Services (HES). Additional licensing arrangements with other industry companies are anticipated in 2004-2005. Ongoing Phase 2 and Phase 3 field-testing continues to confirm applications of both real-time technologies. Technical data transfer to industry is ongoing via Internet tech-transfer and various industry presentations and publications including Society of Petroleum Engineers. These real-time enhanced stimulation procedures should significantly

  19. An Intelligent Systems Approach to Reservoir Characterization. Final Report

    International Nuclear Information System (INIS)

    Shahab D. Mohaghegh; Jaime Toro; Thomas H. Wilson; Emre Artun; Alejandro Sanchez; Sandeep Pyakurel


    Today, the major challenge in reservoir characterization is integrating data coming from different sources in varying scales, in order to obtain an accurate and high-resolution reservoir model. The role of seismic data in this integration is often limited to providing a structural model for the reservoir. Its relatively low resolution usually limits its further use. However, its areal coverage and availability suggest that it has the potential of providing valuable data for more detailed reservoir characterization studies through the process of seismic inversion. In this paper, a novel intelligent seismic inversion methodology is presented to achieve a desirable correlation between relatively low-frequency seismic signals, and the much higher frequency wireline-log data. Vertical seismic profile (VSP) is used as an intermediate step between the well logs and the surface seismic. A synthetic seismic model is developed by using real data and seismic interpretation. In the example presented here, the model represents the Atoka and Morrow formations, and the overlying Pennsylvanian sequence of the Buffalo Valley Field in New Mexico. Generalized regression neural network (GRNN) is used to build two independent correlation models between; (1) Surface seismic and VSP, (2) VSP and well logs. After generating virtual VSP's from the surface seismic, well logs are predicted by using the correlation between VSP and well logs. The values of the density log, which is a surrogate for reservoir porosity, are predicted for each seismic trace through the seismic line with a classification approach having a correlation coefficient of 0.81. The same methodology is then applied to real data taken from the Buffalo Valley Field, to predict inter-well gamma ray and neutron porosity logs through the seismic line of interest. The same procedure can be applied to a complete 3D seismic block to obtain 3D distributions of reservoir properties with less uncertainty than the geostatistical

  20. Reservoir Cathode for Electric Space Propulsion Project (United States)

    National Aeronautics and Space Administration — We propose a reservoir cathode to improve performance in both ion and Hall-effect thrusters. We propose to adapt our existing reservoir cathode technology to this...

  1. 49 CFR 236.792 - Reservoir, equalizing. (United States)


    ... Reservoir, equalizing. An air reservoir connected with and adding volume to the top portion of the equalizing piston chamber of the automatic brake valve, to provide uniform service reductions in brake pipe...

  2. Dissolved methane in Indian freshwater reservoirs

    Digital Repository Service at National Institute of Oceanography (India)

    Narvenkar, G.; Naqvi, S.W.A.; Kurian, S.; Shenoy, D.M.; Pratihary, A.K.; Naik, H.; Patil, S.; Sarkar, A.; Gauns, M.

    Emission of methane (CH4), a potent greenhouse gas, from tropical reservoirs is of interest because such reservoirs experience conducive conditions for CH4 production through anaerobic microbial activities. It has been suggested that Indian...

  3. The Methane Hydrate Reservoir System (United States)

    Flemings, P. B.; Liu, X.


    We use multi phase flow modeling and field examples (Hydrate Ridge, offshore Oregon and Blake Ridge, offshore North Carolina) to demonstrate that the methane hydrate reservoir system links traditional and non- traditional hydrocarbon system components: free gas flow is a fundamental control on this system. As in a traditional hydrocarbon reservoir, gas migrates into the hydrate reservoir as a separate phase (secondary migration) where it is trapped in a gas column beneath the base of the hydrate layer. With sufficient gas supply, buoyancy forces exceed either the capillary entry pressure of the cap rock or the fracture strength of the cap rock, and gas leaks into the hydrate stability zone, or cap rock. When gas enters the hydrate stability zone and forms hydrate, it becomes a very non traditional reservoir. Free gas forms hydrate, depletes water, and elevates salinity until pore water is too saline for further hydrate formation: salinity and hydrate concentration increase upwards from the base of the regional hydrate stability zone (RHSZ) to the seafloor and the base of the hydrate stability zone has significant topography. Gas chimneys couple the free gas zone to the seafloor through high salinity conduits that are maintained at the three-phase boundary by gas flow. As a result, significant amounts of gaseous methane can bypass the RHSZ, which implies a significantly smaller hydrate reservoir than previously envisioned. Hydrate within gas chimneys lie at the three-phase boundary and thus small increases in temperature or decreases in pressure can immediately transport methane into the ocean. This type of hydrate deposit may be the most economical for producing energy because it has very high methane concentrations (Sh > 70%) located near the seafloor, which lie on the three-phase boundary.

  4. Greenhouse gas emissions from reservoir water surfaces: A new global synthesis (United States)

    Collectively, reservoirs created by dams are thought to be an important source ofgreenhouse gases (GHGs) to the atmosphere. So far, efforts to quantify, model, andmanage these emissions have been limited by data availability and inconsistenciesin methodological approach. Here we ...

  5. The microbiology of hydorcarbon degradation in subsurface petroleum reservoirs: perspectives and prospects.

    NARCIS (Netherlands)

    Roling, W.F.M.; Head, I.M.; Larter, S.R.


    The majority of the Earth's petroleum resource is partly biodegraded. This is of considerable practical significance and can limit economic exploitation of petroleum reserves and lead to problems during petroleum production. Knowledge of the microorganisms present in petroleum reservoirs, their

  6. Optimizing Fracture Treatments in a Mississippian "Chat" Reservoir, South-Central Kansas

    Energy Technology Data Exchange (ETDEWEB)

    K. David Newell; Saibal Bhattacharya; Alan Byrnes; W. Lynn Watney; Willard Guy


    This project is a collaboration of Woolsey Petroleum Corporation (a small independent operator) and the Kansas Geological Survey. The project will investigate geologic and engineering factors critical for designing hydraulic fracture treatments in Mississippian ''chat'' reservoirs. Mississippian reservoirs, including the chat, account for 159 million m3 (1 billion barrels) of the cumulative oil produced in Kansas. Mississippian reservoirs presently represent {approx}40% of the state's 5.6*106m3 (35 million barrels) annual production. Although geographically widespread, the ''chat'' is a heterogeneous reservoir composed of chert, cherty dolomite, and argillaceous limestone. Fractured chert with micro-moldic porosity is the best reservoir in this 18- to 30-m-thick (60- to 100-ft) unit. The chat will be cored in an infill well in the Medicine Lodge North field (417,638 m3 [2,626,858 bbls] oil; 217,811,000 m3 [7,692,010 mcf] gas cumulative production; discovered 1954). The core and modern wireline logs will provide geological and petrophysical data for designing a fracture treatment. Optimum hydraulic fracturing design is poorly defined in the chat, with poor correlation of treatment size to production increase. To establish new geologic and petrophysical guidelines for these treatments, data from core petrophysics, wireline logs, and oil-field maps will be input to a fracture-treatment simulation program. Parameters will be established for optimal size of the treatment and geologic characteristics of the predicted fracturing. The fracturing will be performed and subsequent wellsite tests will ascertain the results for comparison to predictions. A reservoir simulation program will then predict the rate and volumetric increase in production. Comparison of the predicted increase in production with that of reality, and the hypothetical fracturing behavior of the reservoir with that of its actual behavior, will serve as tests of

  7. Reservoir characterization of the Ordovician Red River Formation in southwest Williston Basin Bowman County, ND and Harding County, SD

    Energy Technology Data Exchange (ETDEWEB)

    Sippel, M.A.; Luff, K.D.; Hendricks, M.L.; Eby, D.E.


    This topical report is a compilation of characterizations by different disciplines of the Red River Formation in the southwest portion of the Williston Basin and the oil reservoirs which it contains in an area which straddles the state line between North Dakota and South Dakota. Goals of the report are to increase understanding of the reservoir rocks, oil-in-place, heterogeneity, and methods for improved recovery. The report is divided by discipline into five major sections: (1) geology, (2) petrography-petrophysical, (3) engineering, (4) case studies and (5) geophysical. Interwoven in these sections are results from demonstration wells which were drilled or selected for special testing to evaluate important concepts for field development and enhanced recovery. The Red River study area has been successfully explored with two-dimensional (2D) seismic. Improved reservoir characterization utilizing 3-dimensional (3D) and has been investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Targeted drilling from predictions using 3D seismic for porosity development were successful in developing significant reserves at close distances to old wells. Short-lateral and horizontal drilling technologies were tested for improved completion efficiency. Lateral completions should improve economics for both primary and secondary recovery where low permeability is a problem and higher density drilling is limited by drilling cost. Low water injectivity and widely spaced wells have restricted the application of waterflooding in the past. Water injection tests were performed in both a vertical and a horizontal well. Data from these tests were used to predict long-term injection and oil recovery.

  8. Theoretical frameworks for testing relativistic gravity. IV - A compendium of metric theories of gravity and their post-Newtonian limits. (United States)

    Ni, W.-T.


    Metric theories of gravity are compiled and classified according to the types of gravitational fields they contain, and the modes of interaction among those fields. The gravitation theories considered are classified as (1) general relativity, (2) scalar-tensor theories, (3) conformally flat theories, and (4) stratified theories with conformally flat space slices. The post-Newtonian limit of each theory is constructed and its Parametrized Post-Newtonian (PPN) values are obtained by comparing it with Will's version of the formalism. Results obtained here, when combined with experimental data and with recent work by Nordtvedt and Will and by Ni, show that, of all theories thus far examined by our group, the only currently viable ones are general relativity, the Bergmann-Wagoner scalar-tensor theory and its special cases (Nordtvedt; Brans-Dicke-Jordan), and a recent, new vector-tensor theory by Nordtvedt, Hellings, and Will.

  9. A hybrid framework for reservoir characterization using fuzzy ranking and an artificial neural network (United States)

    Wang, Baijie; Wang, Xin; Chen, Zhangxin


    Reservoir characterization refers to the process of quantitatively assigning reservoir properties using all available field data. Artificial neural networks (ANN) have recently been introduced to solve reservoir characterization problems dealing with the complex underlying relationships inherent in well log data. Despite the utility of ANNs, the current limitation is that most existing applications simply focus on directly implementing existing ANN models instead of improving/customizing them to fit the specific reservoir characterization tasks at hand. In this paper, we propose a novel intelligent framework that integrates fuzzy ranking (FR) and multilayer perceptron (MLP) neural networks for reservoir characterization. FR can automatically identify a minimum subset of well log data as neural inputs, and the MLP is trained to learn the complex correlations from the selected well log data to a target reservoir property. FR guarantees the selection of the optimal subset of representative data from the overall well log data set for the characterization of a specific reservoir property; and, this implicitly improves the modeling and predication accuracy of the MLP. In addition, a growing number of industrial agencies are implementing geographic information systems (GIS) in field data management; and, we have designed the GFAR solution (GIS-based FR ANN Reservoir characterization solution) system, which integrates the proposed framework into a GIS system that provides an efficient characterization solution. Three separate petroleum wells from southwestern Alberta, Canada, were used in the presented case study of reservoir porosity characterization. Our experiments demonstrate that our method can generate reliable results.

  10. Reservoir characterization of the Snorre Field


    Gjestvang, Jørgen


    Master's thesis in Petroleum engineering The fluvial sandstone in the Snorre field consists of braided to meander streams deposited in arid and in humid climate that show a clear differences in the sedimentology and reservoir properties, especially the silt content in large part of the reservoir which decrease the reservoir properties and water saturation. The heterogeneity of these fluvial formations combined with the faulting history makes this reservoir highly complex with many local an...

  11. Reservoir resistivity characterization incorporating flow dynamics

    KAUST Repository

    Arango, Santiago


    Systems and methods for reservoir resistivity characterization are provided, in various aspects, an integrated framework for the estimation of Archie\\'s parameters for a strongly heterogeneous reservoir utilizing the dynamics of the reservoir are provided. The framework can encompass a Bayesian estimation/inversion method for estimating the reservoir parameters, integrating production and time lapse formation conductivity data to achieve a better understanding of the subsurface rock conductivity properties and hence improve water saturation imaging.

  12. The Contribution of Reservoirs to Global Land Surface Water Storage Variations

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Tian; Nijssen, Bart; Gao, Huilin; Lettenmaier, Dennis P.


    Man-made reservoirs play a key role in the terrestrial water system. They alter water fluxes at the land surface and impact surface water storage through water management regulations for diverse purposes such as irrigation, municipal water supply, hydropower generation, and flood control. Although most developed countries have established sophisticated observing systems for many variables in the land surface water cycle, long-term and consistent records of reservoir storage are much more limited and not always shared. Furthermore, most land surface hydrological models do not represent the effects of water management activities. Here, the contribution of reservoirs to seasonal water storage variations is investigated using a large-scale water management model to simulate the effects of reservoir management at basin and continental scales. The model was run from 1948 to 2010 at a spatial resolution of 0.258 latitude–longitude. A total of 166 of the largest reservoirs in the world with a total capacity of about 3900 km3 (nearly 60%of the globally integrated reservoir capacity) were simulated. The global reservoir storage time series reflects the massive expansion of global reservoir capacity; over 30 000 reservoirs have been constructed during the past half century, with a mean absolute interannual storage variation of 89 km3. The results indicate that the average reservoir-induced seasonal storage variation is nearly 700 km3 or about 10%of the global reservoir storage. For some river basins, such as the Yellow River, seasonal reservoir storage variations can be as large as 72%of combined snow water equivalent and soil moisture storage.

  13. The development and testing of a linear induction motor being fed from the source with limited electric power (United States)

    Tiunov, V. V.


    The report provides results of the research related to the tubular linear induction motors’ application. The motors’ design features, a calculation model, a description of test specimens for mining and electric power industry are introduced. The most attention is given to the single-phase motors for high voltage switches drives with the usage of inexpensive standard single-phase transformers for motors’ power supply. The method of the motor’s parameters determination, when the motor is being fed from the transformer, working in the overload mode, was described, and the results of it practical usage were good enough for the engineering practice.

  14. Comparison of thermal runaway limits under different test conditions based on a 4.5 kV IGBT

    DEFF Research Database (Denmark)

    Reigosa, Paula Diaz; Prindle, D.; Pâques, Gontran


    runaway takes place. In this paper guidelines are proposed based on the correlation among short circuit withstand capability and off-state leakage current for guarantying reliable operation and ensuring that they are thermally stable under parameter variations. This study is helpful to facilitate...... at high temperatures is given by comparing the different testing methods: Static performance (including and excluding self-heating effects), Short Circuit Safe Operating area and High-Temperature Reverse Bias. Additionally, a thermal model is used to predict the junction temperature at which thermal...

  15. Biofouling on Reservoir in Sea Water (United States)

    Yoon, H.; Eom, C.; Kong, M.; Park, Y.; Chung, K.; Kim, B.


    The organisms which take part in marine biofouling are primarily the attached or sessile forms occurring naturally in the shallower water along the coast [1]. This is mainly because only those organisms with the ability to adapt to the new situations created by man can adhere firmly enough to avoid being washed off. Chemical and microbiological characteristics of the fouling biofilms developed on various surfaces in contact with the seawater were made. The microbial compositions of the biofilm communities formed on the reservoir polymer surfaces were tested for. The quantities of the diverse microorganisms in the biofilm samples developed on the prohibiting polymer reservoir surface were larger when there was no concern about materials for special selection for fouling. To confirm microbial and formation of biofilm on adsorbents was done CLSM (Multi-photon Confocal Laser Scanning Microscope system) analysis. Microbial identified using 16S rRNA. Experiment results, five species which are Vibrio sp., Pseudoalteromonas, Marinomonas, Sulfitobacter, and Alteromonas discovered to reservoir formed biofouling. There are some microorganism cause fouling and there are the others control fouling. The experimental results offered new specific information, concerning the problems in the application of new material as well as surface coating such as anti-fouling coatings. They showed the important role microbial activity in fouling and corrosion of the surfaces in contact with the any seawater. Acknowledgement : This research was supported by the national research project titled "The Development of Technology for Extraction of Resources Dissolved in Seawater" of the Korea Institute of Geoscience and Mineral Resources (KIGAM) funded by the Ministry of Land, Transport and Maritime Affairs. References [1] M. Y. Diego, K. Soren, and D. J. Kim. Prog. Org. Coat. 50, (2004) p.75-104.

  16. Integration of dynamical data in a geostatistical model of reservoir; Integration des donnees dynamiques dans un modele geostatistique de reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Costa Reis, L.


    We have developed in this thesis a methodology of integrated characterization of heterogeneous reservoirs, from geologic modeling to history matching. This methodology is applied to the reservoir PBR, situated in Campos Basin, offshore Brazil, which has been producing since June 1979. This work is an extension of two other thesis concerning geologic and geostatistical modeling of the reservoir PBR from well data and seismic information. We extended the geostatistical litho-type model to the whole reservoir by using a particular approach of the non-stationary truncated Gaussian simulation method. This approach facilitated the application of the gradual deformation method to history matching. The main stages of the methodology for dynamic data integration in a geostatistical reservoir model are presented. We constructed a reservoir model and the initial difficulties in the history matching led us to modify some choices in the geological, geostatistical and flow models. These difficulties show the importance of dynamic data integration in reservoir modeling. The petrophysical property assignment within the litho-types was done by using well test data. We used an inversion procedure to evaluate the petrophysical parameters of the litho-types. The up-scaling is a necessary stage to reduce the flow simulation time. We compared several up-scaling methods and we show that the passage from the fine geostatistical model to the coarse flow model should be done very carefully. The choice of the fitting parameter depends on the objective of the study. In the case of the reservoir PBR, where water is injected in order to improve the oil recovery, the water rate of the producing wells is directly related to the reservoir heterogeneity. Thus, the water rate was chosen as the fitting parameter. We obtained significant improvements in the history matching of the reservoir PBR. First, by using a method we have proposed, called patchwork. This method allows us to built a coherent

  17. 32 CFR 644.4 - Reservoir Projects. (United States)


    ... 32 National Defense 4 2010-07-01 2010-07-01 true Reservoir Projects. 644.4 Section 644.4 National... HANDBOOK Project Planning Civil Works § 644.4 Reservoir Projects. (a) Joint land acquisition policy for reservoir projects. The joint policies of the Department of the Interior and the Department of the Army...

  18. Consumer interaction strength may limit the diversifying effect of intraspecific competition: a test in alewife (Alosa pseudoharengus). (United States)

    Jones, Andrew W; Post, David M


    Intraspecific competition is considered a principal driver of dietary variation, but empirical studies provide mixed support for this mechanism. Here we link comparative and experimental work testing the effects of competition and resource availability on the dietary variation of the alewife (Alosa pseudoharengus). The alewife, a consumer with extreme effects on its resources, was specifically utilized to additionally test the idea that strong interactions between a consumer and its resources can diminish the diversifying effect of competition. First, we compared the short- and long-term diet measures of wild populations across a wide range of densities. Second, in a pair of large-scale field mesocosm experiments, we explored the influence of competition and interaction strength on alewife dietary variation. Results from a whole-lake comparison and field experiments indicated that increasing competition was negatively correlated with population dietary variation. Further, altering the strength of the interaction between the alewife and its prey via prey supplementation eliminated this negative relationship. Collectively, our results suggest that competitive interactions may not drive dietary diversification in the alewife and, potentially, in other highly effective consumers. Our results also indicate that further consideration of the strength of species interactions (and the consumer traits that underlie them) would improve our understanding of the link between intraspecific competition and variation.

  19. Increasing Waterflooding Reservoirs in the Wilmington Oil Field through Improved Reservoir Characterization and Reservoir Management, Class III

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, Roy; Clarke, Don; Walker, Scott; Phillips, Chris; Nguyen, John; Moos, Dan; Tagbor, Kwasi


    This project was intended to increase recoverable waterflood reserves in slope and basin reservoirs through improved reservoir characterization and reservoir management. The particular application of this project is in portions of Fault Blocks IV and V of the Wilmington Oil Field, in Long Beach, California, but the approach is widely applicable in slope and basin reservoirs, transferring technology so that it can be applied in other sections of the Wilmington field and by operators in other slope and basin reservoirs is a primary component of the project.

  20. Use of modified nanoparticles in oil and gas reservoir management

    NARCIS (Netherlands)

    Turkenburg, D.H.; Chin, P.T.K.; Fischer, H.R.


    We describe a water dispersed nano sensor cocktail based on InP/ZnS quantum dots (QDs) and atomic silver clusters with a bright and visible luminescence combined with optimized sensor functionalities for the water flooding process. The QDs and Ag nano sensors were tested in simulated reservoir

  1. Limited hydrolysis combined with controlled Maillard-induced glycation does not reduce immunoreactivity of soy protein for all sera tested. (United States)

    Walter, Jordan; Greenberg, Yana; Sriramarao, P; Ismail, Baraem P


    Combining proteolysis and Maillard-induced glycation was investigated to reduce the immunoreactivity of soy protein. Soy protein was hydrolyzed by Alcalase following response surface methodology utilizing three variables, temperature, time, and enzyme:substrate ratio, with the degree of hydrolysis (DH) and percent reduction in immunoreactivity as response variables. Western blots and ELISA were used to evaluate immunoreactivity using human sera. Data were fitted to appropriate models and prediction equations were generated to determine optimal hydrolysis conditions. The hydrolysate produced under optimized conditions was subjected to glycation with dextran. Hydrolysate produced under optimal conditions had 7.8% DH and a percent reduction in immunoreactivity ranging from 20% to 52%, depending on the sera used. Upon glycation, immunoreactivity was further reduced only when using serum that had the highest soy-specific IgE. This work revealed limitations and provided premises for future studies intended to prove the potency of the combined modification approach to produce a hypoallergenic protein ingredient. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Prototyping and Testing a New Volumetric Curvature Tool for Modeling Reservoir Compartments and Leakage Pathways in the Arbuckle Saline Aquifer: Reducing Uncertainty in CO2 Storage and Permanence

    Energy Technology Data Exchange (ETDEWEB)

    Rush, Jason [Univ. of Kansas and Kansas Geological Survey, Lawrence, KS (United States); Holubnyak, Yevhen [Univ. of Kansas and Kansas Geological Survey, Lawrence, KS (United States); Watney, Willard [Univ. of Kansas and Kansas Geological Survey, Lawrence, KS (United States)


    This DOE-funded project evaluates the utility of seismic volumetric curvature (VC) for predicting stratal and structural architecture diagnostic of paleokarst reservoirs. Of special interest are applications geared toward carbon capture, utilization, and storage (CCUS). VC has been championed for identifying faults (offset <¼ λ) that cannot be imaged by conventional 3-D seismic attributes such as coherence. The objective of this research was to evaluate VC-techniques for reducing uncertainties in reservoir compartmentalization studies and seal risk assessments especially for saline aquifers. A 2000-ft horizontal lateral was purposefully drilled across VC-imaged lineaments—interpreted to record a fractured and a fault-bounded doline—to physically confirm their presence. The 15-mi² study area is located in southeastern Bemis-Shutts Field, which is situated along the crest of the Central Kansas Uplift (CKU) in Ellis County, Kansas. The uppermost Arbuckle (200+ ft) has extensive paleokarst including collapsed paleocaverns and dolines related to exceedingly prolonged pre-Simpson (Sauk–Tippecanoe) and/or pre-Pennsylvanian subaerial exposure. A lateral borehole was successfully drilled across the full extent (~1100 ft) of a VC-inferred paleokarst doline. Triple combo (GR-neutron/density-resistivity), full-wave sonic, and borehole micro-imager logs were successfully run to TD on drill-pipe. Results from the formation evaluation reveal breccias (e.g., crackle, mosaic, chaotic), fractures, faults, vugs (1-6"), and unaffected host strata consistent with the pre-spud interpretation. Well-rounded pebbles were also observed on the image log. VC-inferred lineaments coincide with 20–80-ft wide intervals of high GR values (100+ API), matrix-rich breccias, and faults. To further demonstrate their utility, VC attributes are integrated into a geocellular modeling workflow: 1) to constrain the structural model; 2) to generate facies probability grids, and; 3) to collocate

  3. Radioactive fallout reconstruction from contemporary measurements of reservoir sediments

    International Nuclear Information System (INIS)

    Krey, P.W.; Heit, M.; Miller, K.M.


    The temporal history of atmospheric deposition to a watershed area can be preserved in the sediment of a lake or reservoir that is supplied by the watershed. The 137 Cs and isotopic Pu concentrations with depth were determined in the sediments of two reservoirs, Enterprise and Deer Creek, which are located in widely separated regions of the state of Utah. Our data not only reconstruct the history of the total radioactive fallout in the area, but also permit estimating the contributions from global sources and from the Nevada Test Site detonations in the 1950s

  4. Effect of Balance Board Exercises on Balance Tests and Limits of Stability by Biodex Balance System in Normal Men

    Directory of Open Access Journals (Sweden)

    Ebrahim Esmaeili


    Full Text Available Objective: Despite tilt-board exercises benefits and its role in ligamentus us injury prevention, little research has been done in this case. The goal of this study is investigation of balance exercises effect for six weeks on balance tests and strength of lower extremity ligaments. Materials & Methods: In present Quasi experimental study, case group was consisted of two 17 subjects groups which did balance exercises for 6 weeks (one group on dominant limb and another on non-dominant limb.Control group did not do any exercise in this period. These groups were evaluated and re-evaluated before and after the exercise period by Biodex Balance System. Results: Statistical analysis revealed significant differences between groups (P<0/05. Conclusion: According to our results it can be concluded that tilt-board exercises can be used as a suitable tool to prevent ligamentus us injuries.

  5. Self-Monitoring of Blood Glucose Levels: Evaluating the Impact of a Policy of Quantity Limits on Test-Strip Use and Costs. (United States)

    Gomes, Tara; Martins, Diana; Tadrous, Mina; Paterson, J Michael; Shah, Baiju R; Juurlink, David N; Singh, Samantha; Mamdani, Muhammad M


    To evaluate the impact of new quantity limits for blood glucose test strips (BGTS) in August 2013 on utilization patterns and costs in the elderly population of Ontario, Canada. We conducted a population-based, cross-sectional time series analysis of all individuals 65 years of age and older who received publically funded BGTSs between August 1, 2010, and July 31, 2015, in Ontario, Canada. The number of BGTSs dispensed and the associated costs were measured for 4 diabetes therapy subgroups-insulin, hypoglycemia-inducing oral agents, non-hypoglycemia-inducing oral agents, and no drug therapy-each month during the study period. We used interventional autoregressive integrated moving average (ARIMA) models to assess the impact of Ontario's policy change on test strip use and costs. In the course of the study period, 657,338,177 test strips were dispensed to elderly patients in Ontario, at a total cost of CAN$482.3 million. Introduction of quantity limits was associated with significant reductions in the number of monthly strips dispensed and the associated costs (p<0.0001). In the year following the policy's implementation, test strip use decreased by 22.2% compared with the prior year (from 145,232,024 test strips to 113,007,795 test strips, a net decrease of 32,224,229 strips), resulting in a 22.5% reduction in costs (from $106.5 million to $82.6 million, a net cost reduction of approximately $24 million). The introduction of quantity limits, aligned with guidance from the Canadian Diabetes Association, led to immediate significant reductions in BGTS dispensing and costs. More research is needed to assess the impact of this policy on patient outcomes. Copyright © 2016 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

  6. New experimental limits on violations of the Pauli exclusion principle obtained with the Borexino Counting Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Back, H.O. [Virginia Polytechnic Institute and State Univ., Physics Dept., Blacksburg (United States); Balata, M.; Credico, A. di [I.N.F.N Lab. Nazionali del Gran Sasso, Assergi (Italy); Bari, A. de; Cecchet, G. [Dipt. di Fisica Nucleare e Teorica Univ. and I.N.F.N., Pavia (Italy); Bellefon, A. de; Dadoun, O. [Lab. de Physique Corpusculaire et Cosmologie, Paris (France); Bellini, G.; Bonetti, S.; Caccianiga, B. [Dipt. di Fisica Univ. and I.N.F.N., Milano (Italy); Benziger, J.; Cadonati, L.; Calaprice, F. [Princeton Univ., Dept. of Physics, Princeton (United States); Buck, C. [Max-Planck-Inst. fuer Kernphysik, Heidelberg (Germany); Chen, M. [Queen' s Univ. Stirling Hall, Dept. of Physics, Kingston, Ontario (Canada); D' Angelo, D.; Feilitzsch, F. von [Technische Univ. Muenchen, Garching (Germany); Derbin, A. [Joint Inst. for Nuclear Research, Dubna (Russian Federation); Deutsch, M. [Dept. of Physics, Massachusetts Inst. of Tech., Cambridge (United States); Etenko, A. [RRC Kurchatov Inst., Moscow (Russian Federation); Fernholz, R.; Ford, R.; Franco, D.; Freudiger, B.; Galbiati, C.; Gazzana, S.; Giammarchi, M.G.; Goeger-Neff, M.; Goretti, A.; Grieb, C.; Hampel, W.; Harding, E.; Hartmann, F.X.; Heusser, G.; Ianni, A.; Ianni, A.M.; Kerret, H. de; Kiko, J.; Kirsten, T.; Kobychev, V.V.; Korga, G.; Korschinek, G.; Kozlov, Y.; Kryn, D.; Laubenstein, M.; Lendvai, C.; Leung, M.; Itvinovich, E.L.; Lombardi, P.; Machulin, I.; Malvezzi, S.; Maneira, J.; Manno, I.; Manuzio, D.; Manuzio, G.; Masetti, F.; Martemianov, A.; Mazzucato, U.; McCarty, K.; Meroni, E.; Mention, G.; Miramonti, L.; Monzani, M.E.; Muratova, V.; Musico, P.; Niedermeier, L.; Oberauer, L.; Obolensky, M.; Ortica, F.; Pallavicini, M.; Papp, L.; Perasso, L.; Peiffer, P.; Pocar, A.; Raghavan, R.S.; Ranucci, G.; Razeto, A.; Sabelnikov, A.; Salvo, C.; Scardaoni, R.; Schimizzi, D.; Schoenert, S.; Simgen, H.; Shutt, T.; Skorokhvatov, M.; Smirnov, O.; Sonnenschein, A.; Sotnikov, A.; Sukhotin, S. [and others


    The Pauli exclusion principle (PEP) has been tested for nucleons (n,p) in {sup 12}C and {sup 16}O nuclei, using the results of background measurements with the prototype of the Borexino detector, the Counting Test Facility (CTF). The approach consisted of a search for {gamma}, n, p and/or {alpha}'s emitted in a non-Paulian transition of 1P- shell nucleons to the filled 1S{sub 1/2} shell in nuclei. Similarly, the Pauli-forbidden {beta}{sup {+-}} decay processes were searched for. Due to the extremely low background and the large mass (4.2 tons) of the CTF detector, the following most stringent up-to-date experimental bounds on PEP violating transitions of nucleons have been established: {tau}({sup 12}C{yields}{sup 12}C+{gamma})>2.1.10{sup 27}y, {tau}({sup 12}C{yields}{sup 11}B+p)>5.0.10{sup 26}y, {tau}({sup 12}C({sup 16}O){yields}{sup 11}C({sup 15}O)+n)>3.7.10{sup 26}y, {tau}({sup 12}C{yields}{sup 8}Be+{alpha})>6.1.10{sup 23}y, {tau}({sup 12}C{yields}{sup 12}N+e{sup -}+{nu}{sub e})>7.6.10{sup 27}y and {tau}({sup 12}C{yields}{sup 12}B+e{sup +}+{nu}{sub e})>7.7.10{sup 27}y, all at 90 % C.L. (orig.)

  7. Testing the discrimination and detection limits of WorldView-2 imagery on a challenging invasive plant target (United States)

    Robinson, T. P.; Wardell-Johnson, G. W.; Pracilio, G.; Brown, C.; Corner, R.; van Klinken, R. D.


    Invasive plants pose significant threats to biodiversity and ecosystem function globally, leading to costly monitoring and management effort. While remote sensing promises cost-effective, robust and repeatable monitoring tools to support intervention, it has been largely restricted to airborne platforms that have higher spatial and spectral resolutions, but which lack the coverage and versatility of satellite-based platforms. This study tests the ability of the WorldView-2 (WV2) eight-band satellite sensor for detecting the invasive shrub mesquite (Prosopis spp.) in the north-west Pilbara region of Australia. Detectability was challenged by the target taxa being largely defoliated by a leaf-tying biological control agent (Gelechiidae: Evippe sp. #1) and the presence of other shrubs and trees. Variable importance in the projection (VIP) scores identified bands offering greatest capacity for discrimination were those covering the near-infrared, red, and red-edge wavelengths. Wavelengths between 400 nm and 630 nm (coastal blue, blue, green, yellow) were not useful for species level discrimination in this case. Classification accuracy was tested on three band sets (simulated standard multispectral, all bands, and bands with VIP scores ≥1). Overall accuracies were comparable amongst all band-sets (Kappa = 0.71-0.77). However, mesquite omission rates were unacceptably high (21.3%) when using all eight bands relative to the simulated standard multispectral band-set (9.5%) and the band-set informed by VIP scores (11.9%). An incremental cover evaluation on the latter identified most omissions to be for objects high mapping accuracy of objects >16 m2 allows application for mapping mesquite shrubs and coalesced stands, the former not previously possible, even with 3 m resolution hyperspectral imagery. WV2 imagery offers excellent portability potential for detecting other species where spectral/spatial resolution or coverage has been an impediment. New generation satellite

  8. Electrophoretic characterization of protein interactions suggesting limited feasibility of accelerated shelf-life testing of ultra-high temperature milk. (United States)

    Grewal, Manpreet Kaur; Chandrapala, Jayani; Donkor, Osaana; Apostolopoulos, Vasso; Vasiljevic, Todor


    Accelerated shelf-life testing is applied to a variety of products to estimate keeping quality over a short period of time. The industry has not been successful in applying this approach to ultra-high temperature (UHT) milk because of chemical and physical changes in the milk proteins that take place during processing and storage. We investigated these protein changes, applying accelerated shelf-life principles to UHT milk samples with different fat levels and using native- and sodium dodecyl sulfate-PAGE. Samples of UHT skim and whole milk were stored at 20, 30, 40, and 50°C for 28d. Irrespective of fat content, UHT treatment had a similar effect on the electrophoretic patterns of milk proteins. At the start of testing, proteins were bonded mainly through disulfide and noncovalent interactions. However, storage at and above 30°C enhanced protein aggregation via covalent interactions. The extent of aggregation appeared to be influenced by fat content; whole milk contained more fat than skim milk, implying aggregation via melted or oxidized fat, or both. Based on reduction in loss in absolute quantity of individual proteins, covalent crosslinking in whole milk was facilitated mainly by products of lipid oxidation and increased access to caseins for crosslinking reactions. Maillard and dehydroalanine products were the main contributors involved in protein changes in skim milk. Protein crosslinking appeared to follow a different pathway at higher temperatures (≥40°C) than at lower temperatures, making it very difficult to extrapolate these changes to protein interactions at lower temperatures. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  9. Direct hydrocarbon exploration and gas reservoir development technology

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Young Hoon; Oh, Jae Ho; Jeong, Tae Jin [Korea Inst. of Geology Mining and Materials, Taejon (Korea, Republic of)] [and others


    In order to enhance the capability of petroleum exploration and development techniques, three year project (1994 - 1997) was initiated on the research of direct hydrocarbon exploration and gas reservoir development. This project consists of four sub-projects. (1) Oil(Gas) - source rock correlation technique: The overview of bio-marker parameters which are applicable to hydrocarbon exploration has been illustrated. Experimental analysis of saturated hydrocarbon and bio-markers of the Pohang E and F core samples has been carried out. (2) Study on surface geochemistry and microbiology for hydrocarbon exploration: the test results of the experimental device for extraction of dissolved gases from water show that the device can be utilized for the gas geochemistry of water. (3) Development of gas and gas condensate reservoirs: There are two types of reservoir characterization. For the reservoir formation characterization, calculation of conditional simulation was compared with that of unconditional simulation. In the reservoir fluid characterization, phase behavior calculations revealed that the component grouping is more important than the increase of number of components. (4) Numerical modeling of seismic wave propagation and full waveform inversion: Three individual sections are presented. The first one is devoted to the inversion theory in general sense. The second and the third sections deal with the frequency domain pseudo waveform inversion of seismic reflection data and refraction data respectively. (author). 180 refs., 91 figs., 60 tabs.

  10. Decision Support System for Reservoir Management and Operation in Africa