WorldWideScience

Sample records for wireline log analysis

  1. Electrofacies analysis for coal lithotype profiling based on high-resolution wireline log data

    Science.gov (United States)

    Roslin, A.; Esterle, J. S.

    2016-06-01

    The traditional approach to coal lithotype analysis is based on a visual characterisation of coal in core, mine or outcrop exposures. As not all wells are fully cored, the petroleum and coal mining industries increasingly use geophysical wireline logs for lithology interpretation.This study demonstrates a method for interpreting coal lithotypes from geophysical wireline logs, and in particular discriminating between bright or banded, and dull coal at similar densities to a decimetre level. The study explores the optimum combination of geophysical log suites for training the coal electrofacies interpretation, using neural network conception, and then propagating the results to wells with fewer wireline data. This approach is objective and has a recordable reproducibility and rule set.In addition to conventional gamma ray and density logs, laterolog resistivity, microresistivity and PEF data were used in the study. Array resistivity data from a compact micro imager (CMI tool) were processed into a single microresistivity curve and integrated with the conventional resistivity data in the cluster analysis. Microresistivity data were tested in the analysis to test the hypothesis that the improved vertical resolution of microresistivity curve can enhance the accuracy of the clustering analysis. The addition of PEF log allowed discrimination between low density bright to banded coal electrofacies and low density inertinite-rich dull electrofacies.The results of clustering analysis were validated statistically and the results of the electrofacies results were compared to manually derived coal lithotype logs.

  2. Wire-line logging analysis of the 2007 JOGMEC/NRCan/Aurora Mallik gas hydrate production test well

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, T.; Takayama, T.; Nakamizu, M.; Yamamoto, K. [Japan Oil, Gas and Metals National Corp., Mihama-ku, Chiba (Japan); Dallimore, S.; Mwenifumbo, J.; Wright, F. [Natural Resources Canada, Sidney, BC (Canada). Geological Survey of Canada; Kurihara, M.; Sato, A. [Japan Oil Engineering Co., Chuo-ku, Tokyo (Japan); Al-Jubori, A. [Schlumberger Canada Ltd., Calgary, AB (Canada)

    2008-07-01

    Japan Oil, Gas and Metals National Corporation and Natural Resources Canada performed a full scale production test in the Mallik field, in Canada's Mackenzie Delta in April, 2007 in order to evaluate the productivity of methane hydrate (MH) by the depressurization method. The program involved an extensive wire-line logging program to evaluate reservoir properties; determine production/water injection intervals; evaluate cement bonding; and, interpret MH dissociation behavior throughout the production. The paper presented a review of the extensive wire-line logging program. It showed the role and workflow of wire-line logging applied in the production well. The well log evaluation for MH bearing zone was the primary focus of the paper. The paper discussed the objectives of the program as well as tools used as part of the study, including several new open hole wire-line logging tools such as magnetic resonance scanner, Rt Scanner, sonic scanner, as well as other advanced logging tools used to obtain data on the occurrence of MH, lithology, MH pore saturation, porosity and permeability. Perforation intervals of the production and water injection zones were selected using a multidisciplinary approach. Candidate test intervals considering lithology, MH pore saturation, initial effective permeability and absolute permeability were identified based on the results of geological interpretation and open hole logging analysis. Reservoir layer models were built to allow for reservoir numerical simulations for several perforation scenarios. Using the results of well log analysis, reservoir numerical simulation, and consideration of operational constraints, a MH bearing formation from 1093 to 1105 mKB was selected for 2007 testing. Three zones were selected for injection of produced water. It was concluded that at the perforation interval of the MH bearing formation (1093-1105 mKB) a selective dissociation was observed in the lateral direction. 20 refs., 3 tabs., 9 figs.

  3. Wireline logging tool catalog; 2nd edition

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    This catalog facilitates wireline logging by (1) drawing up programs, (2) showing the adaptation of tools to downhole conditions, drilling fluids, and formations to be measured, and (3) monitoring operations such as recording speeds and calibration control. This edition now represents the tools and services of five additional companies beyond the two companies in the first edition. The participating companies are: BPB Instrument Ltd, Dresser Atlas, Gearhart Geoservices, Micro Log, Prakla Seismos, Schlumberger, and Welex. For quick consultation of the catalog, the tools are classified by ''families.'' For each family of tools, there is a background to the technology and an explanation of the principles of measurement and applications, along with examples of recorded curves. Case documents submitted by service companies include technical data sheets, sketches of tools and their main combinations, and examples of calibration

  4. Prediction of diagenesis and reservoir quality using wireline logs ...

    African Journals Online (AJOL)

    Reservoir quality is mainly controlled by environment deposit type and diagenesis processes. To investigate such subject we usually proceed to microscopic techniques. Absence of outcrops and missing of core samples let us use conventional wireline logs and core lab measurements as primary data. Direct lecture of well ...

  5. Influence of borehole-eccentred tools on wireline and logging-while-drilling sonic logging measurements

    KAUST Repository

    Pardo, David

    2013-02-13

    We describe a numerical study to quantify the influence of tool-eccentricity on wireline (WL) and logging-while-drilling (LWD) sonic logging measurements. Simulations are performed with a height-polynomial-adaptive (hp) Fourier finite-element method that delivers highly accurate solutions of linear visco-elasto-acoustic problems in the frequency domain. The analysis focuses on WL instruments equipped with monopole or dipole sources and LWD instruments with monopole excitation. Analysis of the main propagation modes obtained from frequency dispersion curves indicates that the additional high-order modes arising as a result of borehole-eccentricity interfere with the main modes (i.e., Stoneley, pseudo-Rayleigh and flexural). This often modifies (decreases) the estimation of shear and compressional formation velocities, which should be corrected (increased) to account for borehole-eccentricity effects. Undesired interferences between different modes can occur at different frequencies depending upon the properties of the formation and fluid annulus size, which may difficult the estimation of the formation velocities. © 2013 European Association of Geoscientists & Engineers.

  6. Using Electrical Wireline Logs For Aquifer Characterization In Parts ...

    African Journals Online (AJOL)

    Interpretation by use of quantitative methods of electric log dataset was successfully applied to sandstone aquifers in parts of Anambra Basin of Nigeria. Depth to aquifers varies between 67 and 213m above mean sea level, porosity ranges between 13 and 55%. Transverse (unit) resistance T changes between 0.037 and ...

  7. Quantification of Organic richness through wireline logs: a case study of Roseneath shale formation, Cooper basin, Australia

    Science.gov (United States)

    Ahmad, Maqsood; Iqbal, Omer; Kadir, Askury Abd

    2017-10-01

    The late Carboniferous-Middle Triassic, intracratonic Cooper basin in northeastern South Australia and southwestern Queensland is Australia's foremost onshore hydrocarbon producing region. The basin compromises Permian carbonaceous shale like lacustrine Roseneath and Murteree shale formation which is acting as source and reservoir rock. The source rock can be distinguished from non-source intervals by lower density, higher transit time, higher gamma ray values, higher porosity and resistivity with increasing organic content. In current dissertation we have attempted to compare the different empirical approaches based on density relation and Δ LogR method through three overlays of sonic/resistivity, neutron/resistivity and density/resistivity to quantify Total organic content (TOC) of Permian lacustrine Roseneath shale formation using open hole wireline log data (DEN, GR, CNL, LLD) of Encounter 1 well. The TOC calculated from fourteen density relations at depth interval between 3174.5–3369 meters is averaged 0.56% while TOC from sonic/resistivity, neutron/resistivity and density/resistivity yielded an average value of 3.84%, 3.68%, 4.40%. The TOC from average of three overlay method is yielded to 3.98%. According to geochemical report in PIRSA the Roseneath shale formation has TOC from 1 – 5 wt %.There is unpromising correlations observed for calculated TOC from fourteen density relations and measured TOC on samples. The TOC from average value of three overlays using Δ LogR method showed good correlation with measured TOC on samples.

  8. http Log Analysis

    DEFF Research Database (Denmark)

    Bøving, Kristian Billeskov; Simonsen, Jesper

    2004-01-01

    This article documents how log analysis can inform qualitative studies concerning the usage of web-based information systems (WIS). No prior research has used http log files as data to study collaboration between multiple users in organisational settings. We investigate how to perform http log...... analysis; what http log analysis says about the nature of collaborative WIS use; and how results from http log analysis may support other data collection methods such as surveys, interviews, and observation. The analysis of log files initially lends itself to research designs, which serve to test...... hypotheses using a quantitative methodology. We show that http log analysis can also be valuable in qualitative research such as case studies. The results from http log analysis can be triangulated with other data sources and for example serve as a means of supporting the interpretation of interview data...

  9. Use of wireline logs at Cerro Prieto in identification of the distribution of hydrothermally altered zones and dike locations, and their correlation with reservoir temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Seamount, D.T. Jr.; Elders, W.A.

    1981-01-01

    Downhole electrical and gamma-gamma density logs from nine wells weere studed and these wireline log parameters with petrologic, temperature, and petrophysical data were correlated. Here, wells M-43, T-366, and M-107 are discussed in detail as typical cases. Log data for shales show good correlation with four zones of hydrothermal alteration previously recognized on the basis of characteristic mineral assemblages and temperatures. These zones are the unaltered montmorillonite zone (< 150/sup 0/C), the illite zone (150/sup 0/C to 230/sup 0/C to 245/sup 0/C), the chlorite zone (235/sup 0/C to 300/sup 0/C, equivalent to the calc-silicate I zone in sands), and the feldspar zone (> 300/sup 0/C, equivalent to the calc-silicate II zone in sands),

  10. Correlation of wireline log characteristics with hydrothermal alteration and other reservoir properties of the Salton Sea and Westmorland geothermal fields, Imperial Valley, California, USA

    Energy Technology Data Exchange (ETDEWEB)

    Muramoto, F.S.; Elders, W.A.

    1984-05-01

    A detailed study of wireline logs from 11 wells in the Salton Sea and Westmorland geothermal systems was undertaken in order to determine the effects of hydrothermal alteration on the response of electrical and gamma-gamma density well logs. For the Salton Sea geothermal field, definite correspondence between log responses and hydrothermal mineralogy is evident, which in turn is related to the physical properties of the rocks. Three hydrothermal and one unaltered zone can be identified from log data on shales. These are: (1) the unaltered montmorillonite zone (<100/sup 0/ to 190/sup 0/C); (2) the illite zone (100/sup 0/ to 190/sup 0/C to 230/sup 0/ to 250/sup 0/C); (3) the chlorite zone (230/sup 0/ to 250/sup 0/C to 290/sup 0/ to 300/sup 0/C); and (4) the feldspar zone (>290/sup 0/ to 300/sup 0/C). The characteristic responses on well logs by which these zones are identified result primarily from changes in clay mineralogy of the shales and increases in density with progressive hydrothermal metamorphism. In the Westmorland geothermal field, differentiating mineral zones from log responses was only partially successful. However, analyses of both well log and petrologic data for wells Landers 1 and Kalin Farms 1 suggest that the former is heating up and the latter is cooling.

  11. Simulation of wireline sonic logging measurements acquired with Borehole-Eccentered tools using a high-order adaptive finite-element method

    KAUST Repository

    Pardo, David

    2011-07-01

    The paper introduces a high-order, adaptive finite-element method for simulation of sonic measurements acquired with borehole-eccentered logging instruments. The resulting frequency-domain based algorithm combines a Fourier series expansion in one spatial dimension with a two-dimensional high-order adaptive finite-element method (FEM), and incorporates a perfectly matched layer (PML) for truncation of the computational domain. The simulation method was verified for various model problems, including a comparison to a semi-analytical solution developed specifically for this purpose. Numerical results indicate that for a wireline sonic tool operating in a fast formation, the main propagation modes are insensitive to the distance from the center of the tool to the center of the borehole (eccentricity distance). However, new flexural modes arise with an increase in eccentricity distance. In soft formations, we identify a new dipole tool mode which arises as a result of tool eccentricity. © 2011 Elsevier Inc.

  12. Scientific results from the deepened Lopra-1 borehole, Faroe Islands: Wire-line log-based stratigraphy of flood basalts from the Lopra-1/1A well, Faroe Islands

    Directory of Open Access Journals (Sweden)

    Boldreel, Lars O.

    2006-07-01

    Full Text Available The present study shows that it is possible to use conventional borehole logs to perform a detailed lithological/stratigraphical division of a column of subaerially extruded basalt. A stratigraphical division of the subaerial flood basalts penetrated by the Lopra-1/1A well has been carried out using new wire-line logging data measured in 1996 in the interval 200–2489 m depth. Resistivity data acquired in the interval 200–2178 m depth during 1981 after the initial drilling of the Lopra-1 well have also been incorporated. Eighty-six individual flow units, 18 compound flows and two dolerite dykes have been identified by combining the NPHI porosity, RHOB density, P-, S- and Stonely-sonic transit time, calliper and resistivity logs. Fifty-two sedimentary/tuffaceous layers have also been identified using the CGR and SGR gamma ray and potassium logs in combination with the aforementioned logs. Within the flow units, sonic velocity, density and resistivity are highest in the core where porosity is lowest. This relation is reversed in the uppermost and basal zones of the flow units. The sonic velocity in the core seems to be independent of the thickness of the flow unit. Porous zones seem abundant in some cores and the total section of cores containing porous zones constitutes more than 70% of the thickness of its flow unit, but where porous zones are absent the core makes up only roughly 50% of the thickness of the flow. It is suggested that the flow units with porous cores represent aa flows (88% of the flow units and the others pahoehoe flows (12% of the flow units.The log pattern of the flow units (crust, core and basal zone is similar to log patterns reported from other basalt plateaux. However the patterns in Lopra-1/1A show a larger variation than elsewhere,suggesting that the flow units are more complex vertically than previously thought. Statistical analysis of P-, S- and Stonely-waves, RHOB, NPHI, resistivity, gamma and calliper logs has

  13. Modified method for estimating petroleum source-rock potential using wireline logs, with application to the Kingak Shale, Alaska North Slope

    Science.gov (United States)

    Rouse, William A.; Houseknecht, David W.

    2016-02-11

    In 2012, the U.S. Geological Survey completed an assessment of undiscovered, technically recoverable oil and gas resources in three source rocks of the Alaska North Slope, including the lower part of the Jurassic to Lower Cretaceous Kingak Shale. In order to identify organic shale potential in the absence of a robust geochemical dataset from the lower Kingak Shale, we introduce two quantitative parameters, $\\Delta DT_\\bar{x}$ and $\\Delta DT_z$, estimated from wireline logs from exploration wells and based in part on the commonly used delta-log resistivity ($\\Delta \\text{ }log\\text{ }R$) technique. Calculation of $\\Delta DT_\\bar{x}$ and $\\Delta DT_z$ is intended to produce objective parameters that may be proportional to the quality and volume, respectively, of potential source rocks penetrated by a well and can be used as mapping parameters to convey the spatial distribution of source-rock potential. Both the $\\Delta DT_\\bar{x}$ and $\\Delta DT_z$ mapping parameters show increased source-rock potential from north to south across the North Slope, with the largest values at the toe of clinoforms in the lower Kingak Shale. Because thermal maturity is not considered in the calculation of $\\Delta DT_\\bar{x}$ or $\\Delta DT_z$, total organic carbon values for individual wells cannot be calculated on the basis of $\\Delta DT_\\bar{x}$ or $\\Delta DT_z$ alone. Therefore, the $\\Delta DT_\\bar{x}$ and $\\Delta DT_z$ mapping parameters should be viewed as first-step reconnaissance tools for identifying source-rock potential.

  14. Dual-shale-content method for total organic carbon content evaluation from wireline logs in organic shale

    Directory of Open Access Journals (Sweden)

    Nie Xin

    2017-05-01

    Full Text Available Organic shale is one of the most important unconventional resources all around the world. Total organic carbon (TOC content is an important evaluation parameter of reservoir hydrocarbon source quality. The regular evaluation methods have higher requirements of well logs and core experiment data for statistical regression. Through analyzing the resistivity and gamma ray logging response characteristics of shale content and organic matters, combined with digital rock physics experiment simulation, we put forward and improve the dual-shale-content method for TOC content logging evaluation. The accuracy of this method is verified by actual data processing. The result shows the dual-shale-content method is simple to use and the error is small. And by comparing with the calculation results by using the ΔLogR method, it is revealed that the trend of the TOC content calculated by our method agrees with the core results better. This new method is suitable for the evaluation of TOC content in the area or interval where there is only conventional logs.

  15. Lithostratigraphic and sequence stratigraphic architecture of the Winduck Interval, central Darling Basin, Australia, based on integration of wireline logs, cores and cuttings data

    Science.gov (United States)

    Khalifa, M. KH.; Jones, B. G.; Mahmud, W. M.

    2016-06-01

    An integration of lithostratigraphy and general sedimentary facies character for non-marine rocks can be a powerful tool in understanding the sequence stratigraphic architecture of the subsurface latest Silurian to Early Devonian Winduck Interval in the Blantyre and western Neckarboo sub-basins, central Darling Basin. This study integrates wireline logs (gamma ray and resistivity), cores and cuttings data to determine the sequence stratigraphic subdivision of the study area. The lithostratigraphy of the Winduck Interval could be subdivided into three units (A, B and C, in ascending order) in the four available wells (Mount Emu 1, Kewell East 1, Booligal Creek 1 and Booligal Creek 2). Closer study of the sequence stratigraphy in the approximately 850-m-thick Winduck Interval revealed ten parasequences (A-J) in progradational to retrogradational parasequence sets and three main Winduck sequences, WKS1, WKS2 and WKS3. Use of the suggested sequence stratigraphic model of the Winduck Interval has the potential to refine existing lithostratigraphic schemes and, given the higher resolution and more detailed correlation, may significantly improve subsurface stratigraphic reconstructions and aid in prediction of hydrocarbon-bearing reservoirs.

  16. An algorithm for estimating gas production potential using digital wire-line log data (Cretaceous of northern Montana)

    Science.gov (United States)

    Hester, Timothy C.

    2001-01-01

    This District Surface Water Quality-Assurance Plan documents the standards, policies, and procedures used by the South Carolina District for activities related to the collection, processing, storage, analysis, and publication of surface-water data.

  17. Analysis of Adaptive Interference Cancellation Using Common-Mode Information in Wireline Communications

    Directory of Open Access Journals (Sweden)

    Per Ola Börjesson

    2007-01-01

    Full Text Available Joint processing of common-mode (CM and differential-mode (DM signals in wireline transmission can yield significant improvements in terms of throughput compared to using only the DM signal. Recent work proposed the employment of an adaptive CM-reference-based interference canceller and reported performance improvements based on simulation results. This paper presents a thorough investigation of the cancellation approach. A subchannel model of the CM-aided wireline channel is presented and the Wiener solutions for different adaptation strategies are derived. It is shown that a canceller, whose coefficients are adapted while the far-end transmitter is silent, yields a signal-to-noise power ratio (SNR that is higher than the SNR at the DM channel output for a large class of practically relevant cases. Adaptation while the useful far-end signal is present yields a front-end whose output SNR is considerably lower compared to the SNR of the DM channel output. The results are illustrated by simulations based on channel measurement data.

  18. Cased-hole log analysis and reservoir performance monitoring

    CERN Document Server

    Bateman, Richard M

    2015-01-01

    This book addresses vital issues, such as the evaluation of shale gas reservoirs and their production. Topics include the cased-hole logging environment, reservoir fluid properties; flow regimes; temperature, noise, cement bond, and pulsed neutron logging; and casing inspection. Production logging charts and tables are included in the appendices. The work serves as a comprehensive reference for production engineers with upstream E&P companies, well logging service company employees, university students, and petroleum industry training professionals. This book also: ·       Provides methods of conveying production logging tools along horizontal well segments as well as measurements of formation electrical resistivity through casing ·       Covers new information on fluid flow characteristics in inclined pipe and provides new and improved nuclear tool measurements in cased wells ·       Includes updates on cased-hole wireline formation testing  

  19. Active Wireline Heave Compensation for Ocean Drilling

    Science.gov (United States)

    Goldberg, D.; Liu, T.; Swain, K.; Furman, C.; Iturrino, G. J.

    2014-12-01

    The up-and-down heave motion of a ship causes a similar motion on any instruments tethered on wireline cable below it. If the amplitude of this motion is greater than a few tens of cm, significant discrepancy in the depth below the ship is introduced, causing uncertainty in the acquired data. Large and irregular cabled motions also increase the risk of damaging tethered instruments, particularly those with relatively delicate sensors. In 2005, Schlumberger and Deep Down, Inc built an active wireline heave compensator (AHC) system for use onboard the JOIDES Resolution to compensate for heave motion on wireline logging tools deployed in scientific drill holes. The goals for the new AHC system were to (1) design a reliable heave compensation system; and (2) devise a robust and quantitative methodology for routine assessment of compensation efficiency (CE) during wireline operations. Software programs were developed to monitor CE and the dynamics of logging tools in real-time, including system performance under variable parameters such as water depth, sea state, cable length, logging speed and direction. We present the CE results from the AHC system on the JOIDES Resolution during a 5-year period of recent IODP operations and compare the results to those from previous compensation systems deployed during ODP and IODP. Based on new data under heave conditions of ±0.2-2.0 m and water depths of 300-4,800 m in open holes, the system reduces 65-80% of downhole tool displacement under stationary conditions and 50-60% during normal logging operations. Moreover, down/up tool motion at low speeds (300-600 m/h) reduces the system's CE values by 15-20%, and logging down at higher speeds (1,000-1,200 m/h) reduces CE values by 55-65%. Furthermore, the system yields slightly lower CE values of 40-50% without tension feedback of the downhole cable while logging. These results indicate that the new system's compensation efficiency is comparable to or better than previous systems

  20. Log Analysis Using Splunk Hadoop Connect

    Science.gov (United States)

    2017-06-01

    losses caused by individual components and by interactions between them. One performance difficulty with log analysis is the observer effect. The act of...a loss of connection with a single node that impacts performance. The research used specialized supercomputer system logs to combat and predict...for high reliability, some log messages were corrupt , incomplete, or had an incorrect timestamp. The volume of administrative messages and failures

  1. LHCb Online Log Analysis and Maintenance System

    CERN Document Server

    Garnier, J-C

    2011-01-01

    History has shown, many times computer logs are the only information an administrator may have for an incident, which could be caused either by a malfunction or an attack. Due to the huge amount of logs that are produced from large-scale IT infrastructures, such as LHCb Online, critical information may be overlooked or simply be drowned in a sea of other messages. This clearly demonstrates the need for an automatic system for long-term maintenance and real time analysis of the logs. We have constructed a low cost, fault tolerant centralized logging system which is able to do in-depth analysis and cross-correlation of every log. This system is capable of handling O(10000) different log sources and numerous formats, while trying to keep the overhead as low as possible. It provides log gathering and management, Offline analysis and online analysis. We call Offline analysis the procedure of analyzing old logs for critical information, while Online analysis refer to the procedure of early alerting and reacting. ...

  2. Analysis of Web Proxy Logs

    Science.gov (United States)

    Fei, Bennie; Eloff, Jan; Olivier, Martin; Venter, Hein

    Network forensics involves capturing, recording and analysing network audit trails. A crucial part of network forensics is to gather evidence at the server level, proxy level and from other sources. A web proxy relays URL requests from clients to a server. Analysing web proxy logs can give unobtrusive insights to the browsing behavior of computer users and provide an overview of the Internet usage in an organisation. More importantly, in terms of network forensics, it can aid in detecting anomalous browsing behavior. This paper demonstrates the use of a self-organising map (SOM), a powerful data mining technique, in network forensics. In particular, it focuses on how a SOM can be used to analyse data gathered at the web proxy level.

  3. Broadband Wireline Provider Service Summary; BBRI_wirelineSum12

    Data.gov (United States)

    University of Rhode Island Geospatial Extension Program — This dataset represents the availability of broadband Internet access in Rhode Island via all wireline technologies assessed by Broadband Rhode Island. Broadband...

  4. Field project to obtain pressure core, wireline log, and production test data for evaluation of CO/sub 2/ flooding potential, Conoco MCA unit well No. 358, Maljamar Field, Lea County, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Swift, T.E.; Marlow, R.E.; Wilhelm, M.H.; Goodrich, J.H.; Kumar, R.M.

    1981-11-01

    This report describes part of the work done to fulfill a contract awarded to Gruy Federal, Inc., by the Department of Energy (DOE) on Feburary 12, 1979. The work includes pressure-coring and associated logging and testing programs to provide data on in-situ oil saturation, porosity and permeability distribution, and other data needed for resource characterization of fields and reservoirs in which CO/sub 2/ injection might have a high probability of success. This report details the second such project. Core porosities agreed well with computed log porosities. Core water saturation and computed log porosities agree fairly well from 3692 to 3712 feet, poorly from 3712 to 3820 feet and in a general way from 4035 to 4107 feet. Computer log analysis techniques incorporating the a, m, and n values obtained from Core Laboratories analysis did not improve the agreement of log versus core derived water saturations. However, both core and log analysis indicated the ninth zone had the highest residual hydrocarbon saturations and production data confirmed the validity of oil saturation determinations. Residual oil saturation, for the perforated and tested intervals were 259 STB/acre-ft for the interval from 4035 to 4055 feet, and 150 STB/acre-ft for the interval from 3692 to 3718 feet. Nine BOPD was produced from the interval 4035 to 4055 feet and no oil was produced from interval 3692 to 3718 feet, qualitatively confirming the relative oil saturations as calculated. The low oil production in the zone from 4022 to 4055 and the lack of production from 3692 to 3718 feet indicated the zone to be at or near residual waterflood conditions as determined by log analysis. This project demonstrates the usefulness of integrating pressure core, log, and production data to realistically evaluate a reservoir for carbon dioxide flood.

  5. MinInversion: A Program for Petrophysical Composition Analysis of Geophysical Well Log Data

    Directory of Open Access Journals (Sweden)

    Adewale Amosu

    2018-02-01

    Full Text Available Knowledge of the composition (mineral and fluid proportions of rock formation lithologies is important for petrophysical and rock physics analysis. The mineralogy of a rock formation can be estimated by solving a system of linear equations that relate a class of geophysical log measurements to the petrophysical properties of known minerals and fluids. This method is useful for carbonate rocks with complex mineralogies and a wide range of other lithologies. Although this method of linear inversion for rock composition is well known, there are no interactive, open-source programs for routinely estimating rock mineralogy from standard digital geophysical wireline logs. We present an interactive open-source program, MinInversion, for constructing a balanced system of linear equations from digital geophysical logs and estimating the rock mineralogy as an inverse problem. MinInversion makes use of a library of petrophysical properties that can be easily expanded and modified by the users. MinInversion also provides several options for solving the system of linear equations and executing the linear matrix inversion including least squares, LU-decomposition and Moore-Penrose generalized inverse methods. In addition, MinInversion enables the estimation of the joint probability distributions for constituent minerals and measured porosity. The joint probability distributions are useful for revealing and analyzing depositional or diagenetic composition trends that affect porosity. The program introduces ease and flexibility to the problems of rock formation composition analysis and the study of the effects of rock composition on porosity.

  6. Requirements-Driven Log Analysis Extended Abstract

    Science.gov (United States)

    Havelund, Klaus

    2012-01-01

    Imagine that you are tasked to help a project improve their testing effort. In a realistic scenario it will quickly become clear, that having an impact is diffcult. First of all, it will likely be a challenge to suggest an alternative approach which is significantly more automated and/or more effective than current practice. The reality is that an average software system has a complex input/output behavior. An automated testing approach will have to auto-generate test cases, each being a pair (i; o) consisting of a test input i and an oracle o. The test input i has to be somewhat meaningful, and the oracle o can be very complicated to compute. Second, even in case where some testing technology has been developed that might improve current practice, it is then likely difficult to completely change the current behavior of the testing team unless the technique is obviously superior and does everything already done by existing technology. So is there an easier way to incorporate formal methods-based approaches than the full edged test revolution? Fortunately the answer is affirmative. A relatively simple approach is to benefit from possibly already existing logging infrastructure, which after all is part of most systems put in production. A log is a sequence of events, generated by special log recording statements, most often manually inserted in the code by the programmers. An event can be considered as a data record: a mapping from field names to values. We can analyze such a log using formal methods, for example checking it against a formal specification. This separates running the system for analyzing its behavior. It is not meant as an alternative to testing since it does not address the important in- put generation problem. However, it offers a solution which testing teams might accept since it has low impact on the existing process. A single person might be assigned to perform such log analysis, compared to the entire testing team changing behavior.

  7. Analysis of RIA standard curve by log-logistic and cubic log-logit models

    International Nuclear Information System (INIS)

    Yamada, Hideo; Kuroda, Akira; Yatabe, Tami; Inaba, Taeko; Chiba, Kazuo

    1981-01-01

    In order to improve goodness-of-fit in RIA standard analysis, programs for computing log-logistic and cubic log-logit were written in BASIC using personal computer P-6060 (Olivetti). Iterative least square method of Taylor series was applied for non-linear estimation of logistic and log-logistic. Hear ''log-logistic'' represents Y = (a - d)/(1 + (log(X)/c)sup(b)) + d As weights either 1, 1/var(Y) or 1/σ 2 were used in logistic or log-logistic and either Y 2 (1 - Y) 2 , Y 2 (1 - Y) 2 /var(Y), or Y 2 (1 - Y) 2 /σ 2 were used in quadratic or cubic log-logit. The term var(Y) represents squares of pure error and σ 2 represents estimated variance calculated using a following equation log(σ 2 + 1) = log(A) + J log(y). As indicators for goodness-of-fit, MSL/S sub(e)sup(2), CMD% and WRV (see text) were used. Better regression was obtained in case of alpha-fetoprotein by log-logistic than by logistic. Cortisol standard curve was much better fitted with cubic log-logit than quadratic log-logit. Predicted precision of AFP standard curve was below 5% in log-logistic in stead of 8% in logistic analysis. Predicted precision obtained using cubic log-logit was about five times lower than that with quadratic log-logit. Importance of selecting good models in RIA data processing was stressed in conjunction with intrinsic precision of radioimmunoassay system indicated by predicted precision. (author)

  8. Broadband Wireline Provider Service: Other Copper Wireline; BBRI_otherCopper12

    Data.gov (United States)

    University of Rhode Island Geospatial Extension Program — This dataset represents the availability of wireline broadband Internet access in Rhode Island via "Other Copper Wireline" technology. In Rhode Island, this category...

  9. Reservoir Characterisation Using Wireline Evaluation And Poststack Seismic Inversion: A Lancelot Field, Southern North Sea, U.K. case study

    International Nuclear Information System (INIS)

    Mojisola, A.

    2002-01-01

    Improved reservoir characterization has been a major factor in the worldwide gain in oil recovery efficiencies over the last decades. This is because inadequate reservoir characterization, usually due to lack of appropriate tools can cause significant errors in petroleum reservoir performance prediction thereby preventing the full potential of a reservoir from being achieved. This work employs the use of wireline logs and the seismic inversion process to characterize the reservoirs in the Lancelot field. An initial reservoir analysis was carried out using the wireline evaluation. Five potential reservoirs were delineated. Thereafter reservoir parameters such as porosity, water saturation, water saturation, net-to-gross ratio of the delineated reservoirs were estimated. The seismic inversion process depends on four factors; the wavelet, the tie between the well logs and the seismic, the inversion algorithm employed and the initial model. Therefore before the main inversion, parameter tests were carried out to determine the best wavelet extraction algorithm and best inversion algorithm suited for he available data. A wavelet with a length of 70ms and a taper length of 20ms gave a close approximation of a zero phase wavelet with a stable spectrum and high dominant frequency. Based on quantitative assessment of the available inversion algorithms, the constrained blocky inversion produced the best result. Acoustic impedance, velocity and porosity sections were produced from the inverted input seismic. By incorporating geological and wireline evaluation results as constraints, the output from the inversion process were analysed. The result shows lateral variation in the reservoirs qualities of the delineated reservoirs. The seismic inversion process confirmed the Rotliegend sandstone as a prospect with a range of porosity predicted from the inversion

  10. SDSS Log Viewer: visual exploratory analysis of large-volume SQL log data

    Science.gov (United States)

    Zhang, Jian; Chen, Chaomei; Vogeley, Michael S.; Pan, Danny; Thakar, Ani; Raddick, Jordan

    2012-01-01

    User-generated Structured Query Language (SQL) queries are a rich source of information for database analysts, information scientists, and the end users of databases. In this study a group of scientists in astronomy and computer and information scientists work together to analyze a large volume of SQL log data generated by users of the Sloan Digital Sky Survey (SDSS) data archive in order to better understand users' data seeking behavior. While statistical analysis of such logs is useful at aggregated levels, efficiently exploring specific patterns of queries is often a challenging task due to the typically large volume of the data, multivariate features, and data requirements specified in SQL queries. To enable and facilitate effective and efficient exploration of the SDSS log data, we designed an interactive visualization tool, called the SDSS Log Viewer, which integrates time series visualization, text visualization, and dynamic query techniques. We describe two analysis scenarios of visual exploration of SDSS log data, including understanding unusually high daily query traffic and modeling the types of data seeking behaviors of massive query generators. The two scenarios demonstrate that the SDSS Log Viewer provides a novel and potentially valuable approach to support these targeted tasks.

  11. Cross-system log file analysis for hypothesis testing

    NARCIS (Netherlands)

    Glahn, Christian

    2008-01-01

    Glahn, C. (2008). Cross-system log file analysis for hypothesis testing. Presented at Empowering Learners for Lifelong Competence Development: pedagogical, organisational and technological issues. 4th TENCompetence Open Workshop. April, 10, 2008, Madrid, Spain.

  12. Development of interpretation models for PFN uranium log analysis

    International Nuclear Information System (INIS)

    Barnard, R.W.

    1980-11-01

    This report presents the models for interpretation of borehole logs for the PFN (Prompt Fission Neutron) uranium logging system. Two models have been developed, the counts-ratio model and the counts/dieaway model. Both are empirically developed, but can be related to the theoretical bases for PFN analysis. The models try to correct for the effects of external factors (such as probe or formation parameters) in the calculation of uranium grade. The theoretical bases and calculational techniques for estimating uranium concentration from raw PFN data and other parameters are discussed. Examples and discussions of borehole logs are included

  13. Automatic Data Logging and Quality Analysis System for Mobile Devices

    Directory of Open Access Journals (Sweden)

    Yong-Yi Fanjiang

    2017-01-01

    Full Text Available The testing phase of mobile device products includes two important test projects that must be completed before shipment: the field trial and the beta user trial. During the field trial, the product is certified based on its integration and stability with the local operator’s system, and, during the beta user trial, the product is certified by multiple users regarding its daily use, where the goal is to detect and solve early problems. In the traditional approach used to issue returns, testers must log into a web site, fill out a problem form, and then go through a browser or FTP to upload logs; however, this is inconvenient, and problems are reported slowly. Therefore, we propose an “automatic logging analysis system” (ALAS to construct a convenient test environment and, using a record analysis (log parser program, automate the parsing of log files and have questions automatically sent to the database by the system. Finally, the mean time between failures (MTBF is used to establish measurement indicators for the beta user trial.

  14. An Analysis of the Differences among Log Scaling Methods and Actual Log Volume

    Science.gov (United States)

    R. Edward Thomas; Neal D. Bennett

    2017-01-01

    Log rules estimate the volume of green lumber that can be expected to result from the sawing of a log. As such, this ability to reliably predict lumber recovery forms the foundation of log sales and purchase. The more efficient a sawmill, the less the scaling methods reflect the actual volume recovery and the greater the overrun factor. Using high-resolution scanned...

  15. prediction of diagenesis and reservoir quality using wireline logs

    African Journals Online (AJOL)

    E. Mazouz

    2017-05-01

    abreviated in French: TAGS – Trias Argilo-Gréseux Supérieur) seem rare comparatively with those on TAGI. (Lower Triassic, Ladinian to early Carnian); this less importance is probably due to the reduced extent of TAGS compared ...

  16. Bayesian analysis of log Gaussian Cox processes for disease mapping

    DEFF Research Database (Denmark)

    Benes, Viktor; Bodlák, Karel; Møller, Jesper

    We consider a data set of locations where people in Central Bohemia have been infected by tick-borne encephalitis, and where population census data and covariates concerning vegetation and altitude are available. The aims are to estimate the risk map of the disease and to study the dependence...... of the risk on the covariates. Instead of using the common area level approaches we consider a Bayesian analysis for a log Gaussian Cox point process with covariates. Posterior characteristics for a discretized version of the log Gaussian Cox process are computed using markov chain Monte Carlo methods...

  17. Audit and trace log management consolidation and analysis

    CERN Document Server

    Maier, Phillip Q

    2006-01-01

    As regulation and legislation evolve, the critical need for cost-effective and efficient IT audit and monitoring solutions will continue to grow. Audit and Trace Log Management: Consolidation and Analysis offers a comprehensive introduction and explanation of requirements and problem definition, and also delivers a multidimensional solution set with broad applicability across a wide range of organizations. Itprovidesa wealth of information in the form of processwalkthroughs. These include problem determination, requirements gathering,scope definition, risk assessment, compliance objectives,

  18. LOG FILE ANALYSIS AND CREATION OF MORE INTELLIGENT WEB SITES

    Directory of Open Access Journals (Sweden)

    Mislav Šimunić

    2012-07-01

    Full Text Available To enable successful performance of any company or business system, both inthe world and in the Republic of Croatia, among many problems relating to its operationsand particularly to maximum utilization and efficiency of the Internet as a media forrunning business (especially in terms of marketing, they should make the best possible useof the present-day global trends and advantages of sophisticated technologies andapproaches to running a business. Bearing in mind the fact of daily increasing competitionand more demanding market, this paper addresses certain scientific and practicalcontribution to continuous analysis of demand market and adaptation thereto by analyzingthe log files and by retroactive effect on the web site. A log file is a carrier of numerousdata and indicators that should be used in the best possible way to improve the entirebusiness operations of a company. However, this is not always simple and easy. The websites differ in size, purpose, and technology used for designing them. For this very reason,the analytic analysis frameworks should be such that can cover any web site and at thesame time leave some space for analyzing and investigating the specific characteristicof each web site and provide for its dynamics by analyzing the log file records. Thoseconsiderations were a basis for this paper

  19. Financial and Economic Analysis of Reduced Impact Logging

    Science.gov (United States)

    Tom Holmes

    2016-01-01

    Concern regarding extensive damage to tropical forests resulting from logging increased dramatically after World War II when mechanized logging systems developed in industrialized countries were deployed in the tropics. As a consequence, tropical foresters began developing logging procedures that were more environmentally benign, and by the 1990s, these practices began...

  20. Developments in wireline in-situ rock stress measurement

    Energy Technology Data Exchange (ETDEWEB)

    Pedroso, Carlos [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Canas, Jesus A.; Holzberg, Bruno; Gmach, Helmut [Schlumberger Servicos de Petroleo Ltda., Rio de Janeiro, RJ (Brazil)

    2008-07-01

    This paper presents recent developments of in-situ stress measurements with wireline tools. The stress measurements are based on the micro hydraulic techniques that can be initialized when an interval is pressurized by pumping fluid until a tensile fracture begins or by packers fracturing (sleeve fracturing). Ultrasonic and Micro-resistivity borehole image logs (before and after the testes) are used as a complement, in order to observe the fractures created by the tests, evaluating the mechanical behavior of the formation. An offshore case study is presented, where shales and tight sandstones at depths deeper than 4500 meters depth were successfully evaluated. A workflow to succeed on stress measurements on such environments is proposed, what includes a planning phase: where breakdown pressures ranges are estimated and compared with the capacity of the tools, a Real Time Monitoring phase, where a decision tree is proposed to help on quick decisions while testing, and an interpretation phase, where appropriate techniques are indicated to evaluate the results. Also, the paper presents the main operational needs to succeed on such environments. Basically, such tests require an entirely software controlled, motorized and modular design tool consisting of dual packer (DP), pump out and flow control modules (Figure 1). These modules were upgraded for the present environment: conditions such as temperatures above 300 deg F, formation pressures above 10,000 psia, very low formation permeability, high pressure differential need and oil based mud (OBM) environment. (author)

  1. Towards an entropy-based analysis of log variability

    DEFF Research Database (Denmark)

    Back, Christoffer Olling; Debois, Søren; Slaats, Tijs

    2017-01-01

    the development of hybrid miners: given a (sub-)log, can we determine a priori whether the log is best suited for imperative or declarative mining? We propose using the concept of entropy, commonly used in information theory. We consider different measures for entropy that could be applied and show through...... experimentation on both synthetic and real-life logs that these entropy measures do indeed give insights into the complexity of the log and can act as an indicator of which mining paradigm should be used....

  2. Towards an Entropy-based Analysis of Log Variability

    DEFF Research Database (Denmark)

    Back, Christoffer Olling; Debois, Søren; Slaats, Tijs

    2018-01-01

    the development of hybrid miners: given a log, can we determine a priori whether the log is best suited for imperative or declarative mining? We propose using the concept of entropy, commonly used in information theory. We consider different measures for entropy that could be applied and show through...... experimentation on both synthetic and real-life logs that these entropy measures do indeed give insights into the complexity of the log and can act as an indicator of which mining paradigm should be used....

  3. VT Wireline Broadband Availability by Census Block - 06-2013

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VTBB201306 VT Broadband Availability Dataset represents wireline and wireless 'broadband service' availability in VT as of 6/30/2013. This...

  4. VT Wireline Broadband Availability by Census Block - 12-2011

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VTBB201112 VT Broadband Availability Dataset represents wireline and wireless 'broadband service' availability in VT as of 12/31/2011. This...

  5. VT Wireline Broadband Availability by Census Block - 06-2011

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VTBB201106 VT Broadband Availability Dataset represents wireline and wireless 'broadband service' availability in VT as of 6/30/2011. This...

  6. VT Wireline Broadband Availability by Census Block - 12-2010

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VTBB201012 VT Broadband Availability Dataset represents wireline and wireless 'broadband service' availability in VT as of 12/31/2010. This...

  7. VT Wireline Broadband Availability by Census Block - 06-2010

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VTBB201006 VT Broadband Availability Dataset represents wireline and wireless 'broadband service' availability in VT as of 6/30/2010. This...

  8. VT Wireline Broadband Availability by Census Block - 12-2012

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VTBB201212 VT Broadband Availability Dataset represents wireline and wireless 'broadband service' availability in VT as of 12/31/2012. This...

  9. An Analysis Platform for Mobile Ad Hoc Network (MANET) Scenario Execution Log Data

    Science.gov (United States)

    2016-01-01

    ARL-TR-7574 ● JAN 2016 US Army Research Laboratory An Analysis Platform for Mobile Ad Hoc Network (MANET) Scenario Execution Log ...Analysis Platform for Mobile Ad Hoc Network (MANET) Scenario Execution Log Data by Jaime C Acosta and Yadira Jacquez Survivability/Lethality Analysis...August 2015 4. TITLE AND SUBTITLE An Analysis Platform for Mobile Ad Hoc Network (MANET) Scenario Execution Log Data 5a. CONTRACT NUMBER 5b. GRANT

  10. Handbook on nuclear data for borehole logging and mineral analysis

    International Nuclear Information System (INIS)

    1993-01-01

    In nuclear geophysics, an extension of the nuclear data available for reactor and shielding calculations, is required. In general, the problems and the methods of attack are the same, but in nuclear geophysics the environment is earth materials, with virtually all the natural elements in the Periodic Table involved, although not at the same time. In addition, the geometrical configurations encountered in nuclear geophysics are very different from those associated with reactor and shielding design, and they can impose a different demand on the required accuracy of the nuclear data and on the dependence on the calculational approach. Borehole logging is a very good example, since an experimental investigation aimed at varying only one parameter (e.g. moisture content) whilst keeping all the others constant in a geologically complex system that effectively exhibits 'infinite geometry' for neutrons and γ rays is virtually impossible. An increasingly important are of nuclear geophysics is the on-line analysis of natural materials such as coal (e.g. C, H, O, Al, Si, Ca, Fe, Cl, S, N,) the raw materials of the cement industry (S, Na, K, Al, Si, Ca, Fe, Mn, Ti, P, Mg, F, O), and mined ores of Fe, Al, Mn, Cu, Ni, Ag and Au, amongst others. Refs, figs and tabs

  11. Artificial neural network modeling and cluster analysis for organic facies and burial history estimation using well log data: A case study of the South Pars Gas Field, Persian Gulf, Iran

    Science.gov (United States)

    Alizadeh, Bahram; Najjari, Saeid; Kadkhodaie-Ilkhchi, Ali

    2012-08-01

    Intelligent and statistical techniques were used to extract the hidden organic facies from well log responses in the Giant South Pars Gas Field, Persian Gulf, Iran. Kazhdomi Formation of Mid-Cretaceous and Kangan-Dalan Formations of Permo-Triassic Data were used for this purpose. Initially GR, SGR, CGR, THOR, POTA, NPHI and DT logs were applied to model the relationship between wireline logs and Total Organic Carbon (TOC) content using Artificial Neural Networks (ANN). The correlation coefficient (R2) between the measured and ANN predicted TOC equals to 89%. The performance of the model is measured by the Mean Squared Error function, which does not exceed 0.0073. Using Cluster Analysis technique and creating a binary hierarchical cluster tree the constructed TOC column of each formation was clustered into 5 organic facies according to their geochemical similarity. Later a second model with the accuracy of 84% was created by ANN to determine the specified clusters (facies) directly from well logs for quick cluster recognition in other wells of the studied field. Each created facies was correlated to its appropriate burial history curve. Hence each and every facies of a formation could be scrutinized separately and directly from its well logs, demonstrating the time and depth of oil or gas generation. Therefore potential production zone of Kazhdomi probable source rock and Kangan- Dalan reservoir formation could be identified while well logging operations (especially in LWD cases) were in progress. This could reduce uncertainty and save plenty of time and cost for oil industries and aid in the successful implementation of exploration and exploitation plans.

  12. Local regularity analysis of strata heterogeneities from sonic logs

    Directory of Open Access Journals (Sweden)

    S. Gaci

    2010-09-01

    Full Text Available Borehole logs provide geological information about the rocks crossed by the wells. Several properties of rocks can be interpreted in terms of lithology, type and quantity of the fluid filling the pores and fractures.

    Here, the logs are assumed to be nonhomogeneous Brownian motions (nhBms which are generalized fractional Brownian motions (fBms indexed by depth-dependent Hurst parameters H(z. Three techniques, the local wavelet approach (LWA, the average-local wavelet approach (ALWA, and Peltier Algorithm (PA, are suggested to estimate the Hurst functions (or the regularity profiles from the logs.

    First, two synthetic sonic logs with different parameters, shaped by the successive random additions (SRA algorithm, are used to demonstrate the potential of the proposed methods. The obtained Hurst functions are close to the theoretical Hurst functions. Besides, the transitions between the modeled layers are marked by Hurst values discontinuities. It is also shown that PA leads to the best Hurst value estimations.

    Second, we investigate the multifractional property of sonic logs data recorded at two scientific deep boreholes: the pilot hole VB and the ultra deep main hole HB, drilled for the German Continental Deep Drilling Program (KTB. All the regularity profiles independently obtained for the logs provide a clear correlation with lithology, and from each regularity profile, we derive a similar segmentation in terms of lithological units. The lithological discontinuities (strata' bounds and faults contacts are located at the local extrema of the Hurst functions. Moreover, the regularity profiles are compared with the KTB estimated porosity logs, showing a significant relation between the local extrema of the Hurst functions and the fluid-filled fractures. The Hurst function may then constitute a tool to characterize underground heterogeneities.

  13. Local regularity analysis of strata heterogeneities from sonic logs

    Science.gov (United States)

    Gaci, S.; Zaourar, N.; Hamoudi, M.; Holschneider, M.

    2010-09-01

    Borehole logs provide geological information about the rocks crossed by the wells. Several properties of rocks can be interpreted in terms of lithology, type and quantity of the fluid filling the pores and fractures. Here, the logs are assumed to be nonhomogeneous Brownian motions (nhBms) which are generalized fractional Brownian motions (fBms) indexed by depth-dependent Hurst parameters H(z). Three techniques, the local wavelet approach (LWA), the average-local wavelet approach (ALWA), and Peltier Algorithm (PA), are suggested to estimate the Hurst functions (or the regularity profiles) from the logs. First, two synthetic sonic logs with different parameters, shaped by the successive random additions (SRA) algorithm, are used to demonstrate the potential of the proposed methods. The obtained Hurst functions are close to the theoretical Hurst functions. Besides, the transitions between the modeled layers are marked by Hurst values discontinuities. It is also shown that PA leads to the best Hurst value estimations. Second, we investigate the multifractional property of sonic logs data recorded at two scientific deep boreholes: the pilot hole VB and the ultra deep main hole HB, drilled for the German Continental Deep Drilling Program (KTB). All the regularity profiles independently obtained for the logs provide a clear correlation with lithology, and from each regularity profile, we derive a similar segmentation in terms of lithological units. The lithological discontinuities (strata' bounds and faults contacts) are located at the local extrema of the Hurst functions. Moreover, the regularity profiles are compared with the KTB estimated porosity logs, showing a significant relation between the local extrema of the Hurst functions and the fluid-filled fractures. The Hurst function may then constitute a tool to characterize underground heterogeneities.

  14. Log-transformation and its implications for data analysis

    Science.gov (United States)

    FENG, Changyong; WANG, Hongyue; LU, Naiji; CHEN, Tian; HE, Hua; LU, Ying; TU, Xin M.

    2014-01-01

    Summary The log-transformation is widely used in biomedical and psychosocial research to deal with skewed data. This paper highlights serious problems in this classic approach for dealing with skewed data. Despite the common belief that the log transformation can decrease the variability of data and make data conform more closely to the normal distribution, this is usually not the case. Moreover, the results of standard statistical tests performed on log-transformed data are often not relevant for the original, non-transformed data.We demonstrate these problems by presenting examples that use simulated data. We conclude that if used at all, data transformations must be applied very cautiously. We recommend that in most circumstances researchers abandon these traditional methods of dealing with skewed data and, instead, use newer analytic methods that are not dependent on the distribution the data, such as generalized estimating equations (GEE). PMID:25092958

  15. Analysis of Truck Downtimes Using Log Dispersion Plot | Temeng ...

    African Journals Online (AJOL)

    This paper uses log dispersion plot to analyse downtimes of a fleet of 22 dump trucks from the. Nchanga Open Pit, Zambia over a period of two months. Downtimes were categorised into breakdown codes to determine which ones were acute, chronic or a combination of both. The breakdown codes which were critical to the ...

  16. Testing and analysis of internal hardwood log defect prediction models

    Science.gov (United States)

    R. Edward. Thomas

    2011-01-01

    The severity and location of internal defects determine the quality and value of lumber sawn from hardwood logs. Models have been developed to predict the size and position of internal defects based on external defect indicator measurements. These models were shown to predict approximately 80% of all internal knots based on external knot indicators. However, the size...

  17. Analysis of Resident Case Logs in an Anesthesiology Residency Program

    DEFF Research Database (Denmark)

    Yamamoto, Satoshi; Tanaka, Pedro; Madsen, Matias Vested

    2016-01-01

    Our goal in this study was to examine Accreditation Council for Graduate Medical Education case logs for Stanford anesthesia residents graduating in 2013 (25 residents) and 2014 (26 residents). The resident with the fewest recorded patients in 2013 had 43% the number of patients compared with the...

  18. Log-Linear Analysis of Qualitative or Categorical Data in Vocational Education.

    Science.gov (United States)

    Burnett, Michael F.; Parmley, John D.

    1982-01-01

    This article examines the use of the statistical technique of log-linear analysis in the field of vocational education. It introduces the technique and provides a step-by-step example of the log-linear procedure in the analysis of qualitative data. Advantages and limitations of the technique are also discussed. (Author)

  19. Search Log Analysis of the ARTstor Cultural Heritage Image Database

    OpenAIRE

    Lowe, Heather Ann

    2013-01-01

    Search log studies are widely used to gain an understanding of how users interact with an information resource. However, of the studies that examine image databases, the information systems studied are image sites, local collections or general web engines. Few if any studies examine the way users search within a general art and cultural heritage image database. This thesis seeks to discover the types of queries users submit, whether these change over time, and if these differ depending on the...

  20. Introducing log-kappa distributions for solar wind analysis

    Science.gov (United States)

    Leitner, Martin; Vörös, Zolan Z.; Leubner, Manfred P.

    2010-05-01

    The one-point probability density functions (PDFs) obtained from the Wind spacecraft observations of the magnitude of total magnetic field (B) and the solar wind quasi-invariant (QI) are investigated at 1 AU during the years 1995 and 1998. It is known from previous studies that the distributions follow in a rather good approximation a lognormal distribution. This indicates that the underlying random multiplicative processes are skewed, the PDFs are nonsymmetric. The concept of kappa distributions generating PDF tails closer to the observed values is introduced. The skewness, characteristic for the multiplicative processes in the solar wind, is treated on the basis of log-kappa distributions, introduced here for the first time. Normal and lognormal distributions are related in a similar way to each other as the kappa and log-kappa distributions, although the statistics is based on extensive physics in the former and nonextensive physics in the latter cases. We show hat log-kappa PDFs describe the observed distributions in the solar wind more accurately than the lognormal PDFs. In particular, the tails of PDFs corresponding to extreme values of the considered parameters B and QI are better modeled in terms of the nonextensive approach. It indicates that, for the theoretical explanation of the complexity of multisource fluctuations present in 1 year solar wind magnetic and plasma data, both the extensive and the nonextensive physical escription is needed. The variation of the values of kappa obtained from the log-kappa fits can serve as a quantitative measure describing the changing balance between these two distinct physical processes during the solar cycle.

  1. Analysis of artificial fireplace logs by high temperature gas chromatography.

    Science.gov (United States)

    Kuk, Raymond J

    2002-11-01

    High temperature gas chromatography is used to analyze the wax of artificial fireplace logs (firelogs). Firelogs from several different manufacturers are studied and compared. This study shows that the wax within a single firelog is homogeneous and that the wax is also uniform throughout a multi-firelog package. Different brands are shown to have different wax compositions. Firelogs of the same brand, but purchased in different locations, also have different wax compositions. With this information it may be possible to associate an unknown firelog sample to a known sample, but a definitive statement of the origin cannot be made.

  2. Current trends in nuclear borehole logging techniques for elemental analysis

    International Nuclear Information System (INIS)

    1988-06-01

    This report is the result of a consultants' meeting organized by the IAEA and held in Ottawa, Canada, 2-6 November 1987 in order to assess the present technical status of nuclear borehole logging techniques, to find out the well established applications and the development trends. It contains a summary report giving a comprehensive overview of the techniques and applications and a collection of research papers describing work done in industrial institutes. A separate abstract was prepared for each of these 9 papers. Refs, figs and tabs

  3. Communication Base Station Log Analysis Based on Hierarchical Clustering

    Directory of Open Access Journals (Sweden)

    Zhang Shao-Hua

    2017-01-01

    Full Text Available Communication base stations generate massive data every day, these base station logs play an important value in mining of the business circles. This paper use data mining technology and hierarchical clustering algorithm to group the scope of business circle for the base station by recording the data of these base stations.Through analyzing the data of different business circle based on feature extraction and comparing different business circle category characteristics, which can choose a suitable area for operators of commercial marketing.

  4. Exploratory data analysis of the dependencies between skin permeability, molecular weight and log P.

    Science.gov (United States)

    Kilian, D; Lemmer, H J R; Gerber, M; du Preez, J L; du Plessis, J

    2016-06-01

    Molecular weight and log P remain the most frequently used physicochemical properties in models that predict skin permeability. However, several reports over the past two decades have suggested that predictions made by these models may not be sufficiently accurate. In this study, exploratory data analysis of the probabilistic dependencies between molecular weight, log P and log Kp was performed on a dataset constructed from the combination of several popular datasets. The results suggest that, in general, molecular weight and log P are poorly correlated to log Kp. However, after employing several exploratory data analysis techniques, regions within the dataset of statistically significant dependence were identified. As an example of the applicability of the information extracted from the exploratory data analyses, a multiple linear regression model was constructed, bounded by the ranges of dependence. This model gave reasonable approximations to log Kp values obtained from skin permeability studies of selected non-steroidal ant-inflammatory drugs (NSAIDs) administered from a buffer solution and a lipid-based drug delivery system. A method of testing whether a given drug falls within the regions of statistical dependence was also presented. Knowing the ranges within which molecular weight and log P are statistically related to log Kp can supplement existing methods of screening, risk analysis or early drug development decision making to add confidence to predictions made regarding skin permeability.

  5. Query Log Analysis of an Electronic Health Record Search Engine

    Science.gov (United States)

    Yang, Lei; Mei, Qiaozhu; Zheng, Kai; Hanauer, David A.

    2011-01-01

    We analyzed a longitudinal collection of query logs of a full-text search engine designed to facilitate information retrieval in electronic health records (EHR). The collection, 202,905 queries and 35,928 user sessions recorded over a course of 4 years, represents the information-seeking behavior of 533 medical professionals, including frontline practitioners, coding personnel, patient safety officers, and biomedical researchers for patient data stored in EHR systems. In this paper, we present descriptive statistics of the queries, a categorization of information needs manifested through the queries, as well as temporal patterns of the users’ information-seeking behavior. The results suggest that information needs in medical domain are substantially more sophisticated than those that general-purpose web search engines need to accommodate. Therefore, we envision there exists a significant challenge, along with significant opportunities, to provide intelligent query recommendations to facilitate information retrieval in EHR. PMID:22195150

  6. Analysis of Web Server Log Files: Website of Information Management Department of Hacettepe University

    Directory of Open Access Journals (Sweden)

    Mandana Mir Moftakhari

    2015-09-01

    Full Text Available Over the last decade, the importance of analysing information management systems logs has grown, because it has proved that results of the analysing log data can help developing in information system design, interface and architecture of websites. Log file analysis is one of the best ways in order to understand information-searching process of online searchers, users’ needs, interests, knowledge, and prejudices. The utilization of data collected in transaction logs of web search engines helps designers, researchers and web site managers to find complex interactions of users’ goals and behaviours to increase efficiency and effectiveness of websites. Before starting any analysis it should be observed that the log file of the web site contain enough information, otherwise analyser wouldn’t be able to create complete report. In this study we evaluate the website of Information Management Department of Hacettepe University by analysing the server log files. Results show that there is not adequate amount of information in log files which are provided by web site server. The reports which we have created have some information about users’ behaviour and need but they are not sufficient for taking ideal decisions about contents & hyperlink structure of website. It also provides that creating an extended log file is essential for the website. Finally we believe that results can be helpful to improve, redesign and create better website.

  7. Downhole water management and robotic valve manipulation on electric wireline

    Energy Technology Data Exchange (ETDEWEB)

    Schwanitz, Brian [Welltec, Alleroed (Denmark); Petersen, Erik; Farias, Eduardo [Welltec do Brasil Ltda., Rio de Janeiro, RJ (Brazil)

    2008-07-01

    Due to high operating cost and challenging environments, the oil and gas industry is facing an increasing demand to identify areas where new intervention solutions can be applied. Down hole water management and robotic valve manipulation are some of the areas where new approaches are finding critical success. A new technology has enabled increased recovery rates by managing produced water and allowing remote mechanical manipulation of down hole valves on wireline. These services are possible when applying a robotic stroking device and a wireline key tool.This paper will examine the challenges and present case histories illustrating how advanced technological solutions were applied to overcome operational problem in order to enhance reservoir performance and well productivity. Specifically the paper will illustrate both how isolating sliding side door and setting bridge plug in high x-flow using wireline stroker and tractor technologies water cut were reduced from 85% to 5% and from 90% to 45% respectively and shifting isolation sleeve and open and close sliding sleeve replacing conventional methods with a solution that runs on electrical wireline meant a revolution within the oil and gas industry. (author)

  8. Logistics analysis to Improve Deployability (LOG-AID): Field Experiment/Results

    National Research Council Canada - National Science Library

    Evers, Kenneth

    2000-01-01

    .... Under sponsorship of the Air Force Research Laboratory Logistics Readiness Branch (AFRL/HESR), the Synergy team analyzed the current wing-level deployment process as part of the Logistics Analysis to Improve Deployability (LOG-AID) program...

  9. Application of petroleum geophysical well logging and sampling techniques for evaluating aquifer characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Temples, T.J.; Waddell, M.G. [Univ. of South Carolina, Columbia, SC (United States). Earth Science and Resource Inst.

    1996-05-01

    The Hilton Head Island Test Well {number_sign}1 was drilled to a depth of 3,833 feet to evaluate the upper Cretaceous section as a potential ground-water source for Hilton Head Island, South Carolina. The initial plan was to analyze continuous conventional cores. The interval to be analyzed extended from the top of the Eocene to the base of the Cretaceous (approximately 3,500 feet). However, due to the high cost ($400,000), the decision was made to evaluate aquifer potential using advanced geophysical logs with sidewall cores for calibration. The logging suite consisted of a dual induction resistivity, spontaneous potential, compensated neutron, density log, gamma ray, spectral gamma, multipole array acoustic log, caliper, high resolution dipmeter, and a circumferential borehole imaging log. In addition to the wireline logs, 239 sidewall cores and 12 Formation Multi-Test samples were obtained. The log, sidewall core, and FMT information were integrated into an interpretive package using computer generated logs and simple spreadsheets to calculate aquifer properties. Porosity, hydraulic conductivity, transmissivity, and lithologic data derived from this integrated analysis were then used to select screen zones. Water quality in relation to drinking water standards exceeded expectations. The information obtained from the integrated program allowed estimates to be made about the well`s productivity without the expense of conventional coring, flow testing, and completion of the well.

  10. Web application for recording learners’ mouse trajectories and retrieving their study logs for data analysis

    Directory of Open Access Journals (Sweden)

    Yoshinori Miyazaki

    2012-03-01

    Full Text Available With the accelerated implementation of e-learning systems in educational institutions, it has become possible to record learners’ study logs in recent years. It must be admitted that little research has been conducted upon the analysis of the study logs that are obtained. In addition, there is no software that traces the mouse movements of learners during their learning processes, which the authors believe would enable teachers to better understand their students’ behaviors. The objective of this study is to develop a Web application that records students’ study logs, including their mouse trajectories, and to devise an IR tool that can summarize such diversified data. The results of an experiment are also scrutinized to provide an analysis of the relationship between learners’ activities and their study logs.

  11. Lithology and mineralogy recognition from geochemical logging tool data using multivariate statistical analysis.

    Science.gov (United States)

    Konaté, Ahmed Amara; Ma, Huolin; Pan, Heping; Qin, Zhen; Ahmed, Hafizullah Abba; Dembele, N'dji Dit Jacques

    2017-10-01

    The availability of a deep well that penetrates deep into the Ultra High Pressure (UHP) metamorphic rocks is unusual and consequently offers a unique chance to study the metamorphic rocks. One such borehole is located in the southern part of Donghai County in the Sulu UHP metamorphic belt of Eastern China, from the Chinese Continental Scientific Drilling Main hole. This study reports the results obtained from the analysis of oxide log data. A geochemical logging tool provides in situ, gamma ray spectroscopy measurements of major and trace elements in the borehole. Dry weight percent oxide concentration logs obtained for this study were SiO 2 , K 2 O, TiO 2 , H 2 O, CO 2 , Na 2 O, Fe 2 O 3 , FeO, CaO, MnO, MgO, P 2 O 5 and Al 2 O 3 . Cross plot and Principal Component Analysis methods were applied for lithology characterization and mineralogy description respectively. Cross plot analysis allows lithological variations to be characterized. Principal Component Analysis shows that the oxide logs can be summarized by two components related to the feldspar and hydrous minerals. This study has shown that geochemical logging tool data is accurate and adequate to be tremendously useful in UHP metamorphic rocks analysis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. DEVELOPMENT OF A WIRELINE CPT SYSTEM FOR MULTIPLE TOOL USAGE

    Energy Technology Data Exchange (ETDEWEB)

    Stephen P. Farrington; Martin L. Gildea; J. Christopher Bianchi

    1999-08-01

    The first phase of development of a wireline cone penetrometer system for multiple tool usage was completed under DOE award number DE-AR26-98FT40366. Cone penetrometer technology (CPT) has received widespread interest and is becoming more commonplace as a tool for environmental site characterization activities at several Department of Energy (DOE) facilities. Although CPT already offers many benefits for site characterization, the wireline system can improve CPT technology by offering greater utility and increased cost savings. Currently the use of multiple CPT tools during a site characterization (i.e. piezometric cone, chemical sensors, core sampler, grouting tool) must be accomplished by withdrawing the entire penetrometer rod string to change tools. This results in multiple penetrations being required to collect the data and samples that may be required during characterization of a site, and to subsequently seal the resulting holes with grout. The wireline CPT system allows multiple CPT tools to be interchanged during a single penetration, without withdrawing the CPT rod string from the ground. The goal of the project is to develop and demonstrate a system by which various tools can be placed at the tip of the rod string depending on the type of information or sample desired. Under the base contract, an interchangeable piezocone and grouting tool was designed, fabricated, and evaluated. The results of the evaluation indicate that success criteria for the base contract were achieved. In addition, the wireline piezocone tool was validated against ASTM standard cones, the depth capability of the system was found to compare favorably with that of conventional CPT, and the reliability and survivability of the system were demonstrated.

  13. A Computer Program for Flow-Log Analysis of Single Holes (FLASH)

    Science.gov (United States)

    Day-Lewis, F. D.; Johnson, C.D.; Paillet, Frederick L.; Halford, K.J.

    2011-01-01

    A new computer program, FLASH (Flow-Log Analysis of Single Holes), is presented for the analysis of borehole vertical flow logs. The code is based on an analytical solution for steady-state multilayer radial flow to a borehole. The code includes options for (1) discrete fractures and (2) multilayer aquifers. Given vertical flow profiles collected under both ambient and stressed (pumping or injection) conditions, the user can estimate fracture (or layer) transmissivities and far-field hydraulic heads. FLASH is coded in Microsoft Excel with Visual Basic for Applications routines. The code supports manual and automated model calibration. ?? 2011, The Author(s). Ground Water ?? 2011, National Ground Water Association.

  14. Asymptotic log-linear analysis: some cautions concerning sparse frequency tables.

    Science.gov (United States)

    Mielke, Paul W; Berry, Kenneth J; Johnston, Janis E

    2004-02-01

    Traditional asymptotic probability values resulting from log-linear analyses of sparse frequency tables are often much too large. Asymptotic probability values for chi-squared and likelihood-ratio statistics are compared to nonasymptotic and exact probability values for selected log-linear models. The asymptotic probability values are all too often substantially larger than the exact probability values for the analysis of sparse frequency tables. An exact nondirectional permutation method is presented to analyze combined independent multinomial distributions. Exact nondirectional permutation methods to analyze hypergeometric distributions associated with r-way frequency tables are confined to r = 2.

  15. REAL-TIME TRACER MONITORING OF RESERVOIR STIMULATION PROCEDURES VIA ELECTRONIC WIRELINE AND TELEMETRY DATA TRANSMISSION

    Energy Technology Data Exchange (ETDEWEB)

    George L. Scott III

    2005-01-01

    Finalized Phase 2-3 project work has field-proven two separate real-time reservoir processes that were co-developed via funding by the National Energy Technology Laboratory (NETL). Both technologies are presently patented in the United States and select foreign markets; a downhole-commingled reservoir stimulation procedure and a real-time tracer-logged fracturing diagnostic system. Phase 2 and early Phase 3 project work included the research, development and well testing of a U.S. patented gamma tracer fracturing diagnostic system. This stimulation logging process was successfully field-demonstrated; real-time tracer measurement of fracture height while fracturing was accomplished and proven technically possible. However, after the initial well tests, there were several licensing issues that developed between service providers that restricted and minimized Realtimezone's (RTZ) ability to field-test the real-time gamma diagnostic system as was originally outlined for this project. Said restrictions were encountered after when one major provider agreed to license their gamma logging tools to another. Both of these companies previously promised contributory support toward Realtimezone's DE-FC26-99FT40129 project work, however, actual support was less than desired when newly-licensed wireline gamma logging tools from one company were converted by the other from electric wireline into slickline, batter-powered ''memory'' tools for post-stimulation logging purposes. Unfortunately, the converted post-fracture measurement memory tools have no applications in experimentally monitoring real-time movement of tracers in the reservoir concurrent with the fracturing treatment. RTZ subsequently worked with other tracer gamma-logging tool companies for basic gamma logging services, but with lessened results due to lack of multiple-isotope detection capability. In addition to real-time logging system development and well testing, final Phase 2 and

  16. Catching errors with patient-specific pretreatment machine log file analysis.

    Science.gov (United States)

    Rangaraj, Dharanipathy; Zhu, Mingyao; Yang, Deshan; Palaniswaamy, Geethpriya; Yaddanapudi, Sridhar; Wooten, Omar H; Brame, Scott; Mutic, Sasa

    2013-01-01

    A robust, efficient, and reliable quality assurance (QA) process is highly desired for modern external beam radiation therapy treatments. Here, we report the results of a semiautomatic, pretreatment, patient-specific QA process based on dynamic machine log file analysis clinically implemented for intensity modulated radiation therapy (IMRT) treatments delivered by high energy linear accelerators (Varian 2100/2300 EX, Trilogy, iX-D, Varian Medical Systems Inc, Palo Alto, CA). The multileaf collimator machine (MLC) log files are called Dynalog by Varian. Using an in-house developed computer program called "Dynalog QA," we automatically compare the beam delivery parameters in the log files that are generated during pretreatment point dose verification measurements, with the treatment plan to determine any discrepancies in IMRT deliveries. Fluence maps are constructed and compared between the delivered and planned beams. Since clinical introduction in June 2009, 912 machine log file analyses QA were performed by the end of 2010. Among these, 14 errors causing dosimetric deviation were detected and required further investigation and intervention. These errors were the result of human operating mistakes, flawed treatment planning, and data modification during plan file transfer. Minor errors were also reported in 174 other log file analyses, some of which stemmed from false positives and unreliable results; the origins of these are discussed herein. It has been demonstrated that the machine log file analysis is a robust, efficient, and reliable QA process capable of detecting errors originating from human mistakes, flawed planning, and data transfer problems. The possibility of detecting these errors is low using point and planar dosimetric measurements. Copyright © 2013 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

  17. Non-destructive analysis and detection of internal characteristics of spruce logs through X computerized tomography

    International Nuclear Information System (INIS)

    Longuetaud, F.

    2005-10-01

    Computerized tomography allows a direct access to internal features of scanned logs on the basis of density and moisture content variations. The objective of this work is to assess the feasibility of an automatic detection of internal characteristics with the final aim of conducting scientific analyses. The database is constituted by CT images of 24 spruces obtained with a medical CT scanner. Studied trees are representative of several social status and are coming from four stands located in North-Eastern France, themselves are representative of several age, density and fertility classes. The automatic processing developed are the following. First, pith detection in logs dealing with the problem of knot presence and ring eccentricity. The accuracy of the localisation was less than one mm. Secondly, the detection of the sapwood/heart-wood limit in logs dealing with the problem of knot presence (main source of difficulty). The error on the diameter was 1.8 mm which corresponds to a relative error of 1.3 per cent. Thirdly, the detection of the whorls location and comparison with an optical method. Fourthly the detection of individualized knots. This process allows to count knots and to locate them in a log (longitudinal position and azimuth); however, the validation of the method and extraction of branch diameter and inclination are still to be developed. An application of this work was a variability analysis of the sapwood content in the trunk: at the within-tree level, the sapwood width was found to be constant under the living crown; at the between-tree level, a strong correlation was found with the amount of living branches. A great number of analyses are possible from our work results, among others: architectural analysis with the pith tracking and the apex death occurrence; analysis of radial variations of the heart-wood shape; analysis of the knot distribution in logs. (author)

  18. 47 CFR 68.106 - Notification to provider of wireline telecommunications.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Notification to provider of wireline telecommunications. 68.106 Section 68.106 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON... of Terminal Equipment § 68.106 Notification to provider of wireline telecommunications. (a) General...

  19. Formation evaluation in Devonian shale through application of new core and log analysis methods

    International Nuclear Information System (INIS)

    Luffel, D.L.; Guidry, F.K.

    1990-01-01

    In the Devonian shale of the Appalachian Basin all porosity in excess of about 2.5 percent is generally occupied by free hydrocarbons, which is mostly gas, based on results of new core and log analysis methods. In this study, sponsored by the Gas Research Institute, reservoir porosities averaged about 5 percent and free gas content averaged about 2 percent by bulk volume, based on analyses on 519 feet of conventional core in four wells. In this source-rich Devonian shale, which also provides the reservoir storage, the rock everywhere appears to be at connate, or irreducible, water saturation corresponding to two or three percent of bulk volume. This became evident when applying the new core and log analysis methods, along with a new plotting method relating bulk volume of pore fluids to porosity. This plotting method has proved to be a valuable tool: it provides useful insight on the fluid distribution present in the reservoir, it provides a clear idea of porosity required to store free hydrocarbons, it leads to a method of linking formation factor to porosity, and it provides a good quality control method to monitor core and log analysis results. In the Devonian shale an important part of the formation evaluation is to determine the amount of kerogen, since this appears as hydrocarbon-filled porosity to conventional logs. In this study Total Organic Carbon and pyrolysis analyses were made on 93 core samples from four wells. Based on these data a new method was used to drive volumetric kerogen and free oil content, and kerogen was found to range up to 26 percent by volume. A good correlation was subsequently developed to derive kerogen from the uranium response of the spectral gamma ray log. Another important result of this study is the measurement of formation water salinity directly on core samples. Results on 50 measurements in the four study wells ranged from 19,000 to 220,000 ppm NaCl

  20. Identifying Plant Part Composition of Forest Logging Residue Using Infrared Spectral Data and Linear Discriminant Analysis.

    Science.gov (United States)

    Acquah, Gifty E; Via, Brian K; Billor, Nedret; Fasina, Oladiran O; Eckhardt, Lori G

    2016-08-27

    As new markets, technologies and economies evolve in the low carbon bioeconomy, forest logging residue, a largely untapped renewable resource will play a vital role. The feedstock can however be variable depending on plant species and plant part component. This heterogeneity can influence the physical, chemical and thermochemical properties of the material, and thus the final yield and quality of products. Although it is challenging to control compositional variability of a batch of feedstock, it is feasible to monitor this heterogeneity and make the necessary changes in process parameters. Such a system will be a first step towards optimization, quality assurance and cost-effectiveness of processes in the emerging biofuel/chemical industry. The objective of this study was therefore to qualitatively classify forest logging residue made up of different plant parts using both near infrared spectroscopy (NIRS) and Fourier transform infrared spectroscopy (FTIRS) together with linear discriminant analysis (LDA). Forest logging residue harvested from several Pinus taeda (loblolly pine) plantations in Alabama, USA, were classified into three plant part components: clean wood, wood and bark and slash (i.e., limbs and foliage). Five-fold cross-validated linear discriminant functions had classification accuracies of over 96% for both NIRS and FTIRS based models. An extra factor/principal component (PC) was however needed to achieve this in FTIRS modeling. Analysis of factor loadings of both NIR and FTIR spectra showed that, the statistically different amount of cellulose in the three plant part components of logging residue contributed to their initial separation. This study demonstrated that NIR or FTIR spectroscopy coupled with PCA and LDA has the potential to be used as a high throughput tool in classifying the plant part makeup of a batch of forest logging residue feedstock. Thus, NIR/FTIR could be employed as a tool to rapidly probe/monitor the variability of forest

  1. Nuclear Tools For Oilfield Logging-While-Drilling Applications

    Science.gov (United States)

    Reijonen, Jani

    2011-06-01

    Schlumberger is an international oilfield service company with nearly 80,000 employees of 140 nationalities, operating globally in 80 countries. As a market leader in oilfield services, Schlumberger has developed a suite of technologies to assess the downhole environment, including, among others, electromagnetic, seismic, chemical, and nuclear measurements. In the past 10 years there has been a radical shift in the oilfield service industry from traditional wireline measurements to logging-while-drilling (LWD) analysis. For LWD measurements, the analysis is performed and the instruments are operated while the borehole is being drilled. The high temperature, high shock, and extreme vibration environment of LWD imposes stringent requirements for the devices used in these applications. This has a significant impact on the design of the components and subcomponents of a downhole tool. Another significant change in the past few years for nuclear-based oilwell logging tools is the desire to replace the sealed radioisotope sources with active, electronic ones. These active radiation sources provide great benefits compared to the isotopic sources, ranging from handling and safety to nonproliferation and well contamination issues. The challenge is to develop electronic generators that have a high degree of reliability for the entire lifetime of a downhole tool. LWD tool testing and operations are highlighted with particular emphasis on electronic radiation sources and nuclear detectors for the downhole environment.

  2. SU-F-R-12: Prediction of TrueBeam Hardware Issues Using Trajectory Log Analysis

    Energy Technology Data Exchange (ETDEWEB)

    DiCostanzo, D; Ayan, A; Woollard, J; Gupta, N [The Ohio State University, Columbus, OH (United States)

    2016-06-15

    Purpose: To predict potential failures of hardware within the Varian TrueBeam linear accelerator in order to proactively replace parts and decrease machine downtime. Methods: Machine downtime is a problem for all radiation oncology departments and vendors. Most often it is the result of unexpected equipment failure, and increased due to lack of in-house clinical engineering support. Preventative maintenance attempts to assuage downtime, but often is ineffective at preemptively preventing many failure modes such as MLC motor failures, the need to tighten a gantry chain, or the replacement of a jaw motor, among other things. To attempt to alleviate downtime, software was developed in house that determines the maximum value of each axis enumerated in the Truebeam trajectory log files. After patient treatments, this data is stored in a SQL database. Microsoft Power BI is used to plot the average maximum error of each day of each machine as a function of time. The results are then correlated with actual faults that occurred at the machine with the help of Varian service engineers. Results: Over the course of six months, 76,312 trajectory logs have been written into the database and plotted in Power BI. Throughout the course of analysis MLC motors have been replaced on three machines due to the early warning of the trajectory log analysis. The service engineers have also been alerted to possible gantry issues on one occasion due to the aforementioned analysis. Conclusion: Analyzing the trajectory log data is a viable and effective early warning system for potential failures of the TrueBeam linear accelerator. With further analysis and tightening of the tolerance values used to determine a possible imminent failure, it should be possible to pinpoint future issues more thoroughly and for more axes of motion.

  3. Log Usage Analysis: What it Discloses about Use, Information Seeking and Trustworthiness

    Directory of Open Access Journals (Sweden)

    David Nicholas

    2014-06-01

    Full Text Available The Trust and Authority in Scholarly Communications in the Light of the Digital Transition research project1 was a study which investigated the behaviours and attitudes of academic researchers as producers and consumers of scholarly information resources in respect to how they determine authority and trustworthiness. The research questions for the study arose out of CIBER’s studies of the virtual scholar. This paper focuses on elements of this study, mainly an analysis of a scholarly publisher’s usage logs, which was undertaken at the start of the project in order to build an evidence base, which would help calibrate the main methodological tools used by the project: interviews and questionnaire. The specific purpose of the log study was to identify and assess the digital usage behaviours that potentially raise trustworthiness and authority questions. Results from the self-report part of the study were additionally used to explain the logs. The main findings were that: 1 logs provide a good indicator of use and information seeking behaviour, albeit in respect to just a part of the information seeking journey; 2 the ‘lite’ form of information seeking behaviour observed in the logs is a sign of users trying to make their mind up in the face of a tsunami of information as to what is relevant and to be trusted; 3 Google and Google Scholar are the discovery platforms of choice for academic researchers, which partly points to the fact that they are influenced in what they use and read by ease of access; 4 usage is not a suitable proxy for quality. The paper also provides contextual data from CIBER’s previous studies.

  4. An Entry Point for Formal Methods: Specification and Analysis of Event Logs

    Directory of Open Access Journals (Sweden)

    Howard Barringer

    2010-03-01

    Full Text Available Formal specification languages have long languished, due to the grave scalability problems faced by complete verification methods. Runtime verification promises to use formal specifications to automate part of the more scalable art of testing, but has not been widely applied to real systems, and often falters due to the cost and complexity of instrumentation for online monitoring. In this paper we discuss work in progress to apply an event-based specification system to the logging mechanism of the Mars Science Laboratory mission at JPL. By focusing on log analysis, we exploit the "instrumentation" already implemented and required for communicating with the spacecraft. We argue that this work both shows a practical method for using formal specifications in testing and opens interesting research avenues, including a challenging specification learning problem.

  5. Impact of logging on a mangrove swamp in South Mexico: cost / benefit analysis

    Directory of Open Access Journals (Sweden)

    Cristian Tovilla Hernández

    2001-06-01

    Full Text Available Environmental changes caused by logging in a mangrove swamp were studied in Barra de Tecoanapa, Guerrero, Mexico. Original forest included Rhizophora mangle, Laguncularia racemosa, Avicennia germinans and halophytic vegetation, and produced wood (164.03 m3/ha and organic matter (3.9 g/m2/day. A total of 3.5 tons of wood per year were harvested from this area. Later, an average of 2 555 kg of maize per planting cycle were obtained (market value of 88 USD. Succession when the area was abandoned included strictly facultative and glycophyte halophytes (16 families, Cyperaceae and Poaceae were the best represented. After logging, temperatures increased 13 °C in the soil and 11°C in the air, whereas salinity reached 52 psu in the dry season. These modified soil color and sand content increased from 42.6 to 63.4%. Logging was deleterious to species, habitat, biogeochemical and biological cycles, organic matter production, seeds, young plants, genetic exchange conservation of soil and its fertility, coastal protection, and aesthetic value; 3 000 m2 had eroded as the river advanced towards the deforested area (the cost/benefit analysis showed a ratio of 246: 1. There was long-term economic loss for the community and only 30% of the site has recovered after five years.

  6. Wireline Deep Drill for the Exploration of Icy Bodies

    Science.gov (United States)

    Paulsen, G.; Zacny, K.; Mellerowicz, B.; Craft, J.; Bar-Cohen, Y.; Beegle, L.; Sherrit, S.; Badescu, M.; Corsetti, F.; Ibarra, Y.

    2013-01-01

    One of the most pressing current questions in space science is whether life has ever arisen anywhere else in the universe. Water is a critical prerequisite for all life-as-we-know-it, thus the possible exploration targets for extraterrestrial life are bodies that have or had copious liquid: Mars, Europa, and Enceladus. Due to the oxidizing nature of Mars' surface, as well as subsurface liquid water reservoirs present on Europa and Enceladus, the search for evidence of existing life must likely focus on subsurface locations, at depths sufficient to support liquid water or retain biologic signatures. To address these questions, an Auto-Gopher sampler has been developed that is a wireline type drill. This drill is suspended on a tether and its motors and mechanisms are built into a tube that ends with a coring bit. The tether provides the mechanical connection to a rover/lander on a surface as well as power and data communication. Upon penetrating to a target depth, the drill is retracted from the borehole, the core is deposited into a sample transfer system, and the drill is lowered back into the hole. Wireline operation sidesteps one of the major drawbacks of traditional continuous drill string systems by obviating the need for multiple drill sections, which add significantly to the mass and the complexity of the system (i.e. penetration rate was 40 cm per hour). Drilling to 2 meter depth and recovering of cores every 10 cm took a total time of 15 hours (a single step of drilling 10 cm and retrieving the core was 45 minutes). Total energy to reach the 2 m depth was 500 Whr. The Weight on Bit was limited to less than 70 Newton. The core recovery was 100%.

  7. A comparison of two methods of logMAR visual acuity data scoring for statistical analysis

    Directory of Open Access Journals (Sweden)

    O. A. Oduntan

    2009-12-01

    Full Text Available The purpose of this study was to compare two methods of logMAR visual acuity (VA scoring. The two methods are referred to as letter scoring (method 1 and line scoring (method 2. The two methods were applied to VA data obtained from one hundred and forty (N=140 children with oculocutaneous albinism. Descriptive, correlation andregression statistics were then used to analyze the data.  Also, where applicable, the Bland and Altman analysis was used to compare sets of data from the two methods.  The right and left eyes data were included in the study, but because the findings were similar in both eyes, only the results for the right eyes are presented in this paper.  For method 1, the mean unaided VA (mean UAOD1 = 0.39 ±0.15 logMAR. The mean aided (mean ADOD1 VA = 0.50 ± 0.16 logMAR.  For method 2, the mean unaided (mean UAOD2 VA = 0.71 ± 0.15 logMAR, while the mean aided VA (mean ADOD2 = 0.60 ± 0.16 logMAR. The range and mean values of the improvement in VA for both methods were the same. The unaided VAs (UAOD1, UAOD2 and aided (ADOD1, ADOD2 for methods 1 and 2 correlated negatively (Unaided, r = –1, p<0.05, (Aided, r = –1, p<0.05.  The improvement in VA (differences between the unaided and aided VA values (DOD1 and DOD2 were positively correlated (r = +1, p <0.05. The Bland and Altman analyses showed that the VA improvement (unaided – aided VA values (DOD1 and DOD2 were similar for the two methods. Findings indicated that only the improvement in VA could be compared when different scoring methods are used. Therefore the scoring method used in any VA research project should be stated in the publication so that appropriate comparisons could be made by other researchers.

  8. Broadband Wireline Provider Service: Symmetric xDSL; BBRI_DSLsym12

    Data.gov (United States)

    University of Rhode Island Geospatial Extension Program — This dataset represents the availability of wireline broadband Internet access in Rhode Island via Symmetric xDSL technology. Broadband availability is summarized at...

  9. Broadband Wireline Provider Service: Cable Modem - Other; BBRI_cableOther12

    Data.gov (United States)

    University of Rhode Island Geospatial Extension Program — This dataset represents the availability of wireline broadband Internet access in Rhode Island via "Cable Modem - Other" technology. Broadband availability is...

  10. Broadband Wireline Provider Service: Asymmetric xDSL; BBRI_DSLasym12

    Data.gov (United States)

    University of Rhode Island Geospatial Extension Program — This dataset represents the availability of wireline broadband Internet access in Rhode Island via Asymmetric xDSL technology. Broadband availability is summarized...

  11. Broadband Wireline Provider Service: Cable Modem - DOCSIS 3.0; BBRI_cableDOCSIS12

    Data.gov (United States)

    University of Rhode Island Geospatial Extension Program — This dataset represents the availability of wireline broadband Internet access in Rhode Island via "Cable Modem - DOCSIS 3.0" technology. Broadband availability is...

  12. Broadband Wireline Provider Service: Optical Carrier - Fiber to the End User; BBRI_fiber12

    Data.gov (United States)

    University of Rhode Island Geospatial Extension Program — This dataset represents the availability of wireline broadband Internet access in Rhode Island via "Optical Carrier - Fiber to the End User" technology. Broadband...

  13. Converged wireline and wireless signal transport over optical fibre access links

    DEFF Research Database (Denmark)

    Tafur Monroy, Idelfonso; Prince, Kamau; Osadchiy, Alexey Vladimirovich

    2009-01-01

    This article reviews emerging trends in converged optical-wireless communication systems and outline the role that photonic technologies are playing in making the vision of a wireline-wireless converged signal transport network a reality.......This article reviews emerging trends in converged optical-wireless communication systems and outline the role that photonic technologies are playing in making the vision of a wireline-wireless converged signal transport network a reality....

  14. Search Strategies in Nanotechnology Databases: Log Analysis. Journal of Information Processing and Management

    Directory of Open Access Journals (Sweden)

    Nadjla Hariri

    2014-03-01

    Full Text Available Major concern of users of information systems is information retrieval related their information needs, query used by the users is a manifestation of their information needs. The research purpose is to analyze databases of nanotechnology through the query analysis and follow-up users navigation. The research method is transaction log analysis. This study was performed through the analysis of the interaction between users and the database transaction files. Results show that nanothechnology databases users using three methods to retrieve information needs: search engines, referral sites and directly use. In the used directly Bounce Rate have been lower and more pages have been visited. The average length of query is 3.36. And easier search strategies are used to retrieve information.

  15. Technoeconomic analysis of conventional logging systems operating from stump to landing

    Science.gov (United States)

    Raymond L. Sarles; William G. Luppold; William G. Luppold

    1986-01-01

    Analyzes technical and economic factors for six conventional logging systems suitable for operation in eastern forests. Discusses financial risks and business implications for loggers investing in high-production, state-of-the-art logging systems. Provides logging contractors with information useful as a preliminary guide for selection of equipment and systems....

  16. Direct push driven in situ color logging tool (CLT): technique, analysis routines, and application

    Science.gov (United States)

    Werban, U.; Hausmann, J.; Dietrich, P.; Vienken, T.

    2014-12-01

    Direct push technologies have recently seen a broad development providing several tools for in situ parameterization of unconsolidated sediments. One of these techniques is the measurement of soil colors - a proxy information that reveals to soil/sediment properties. We introduce the direct push driven color logging tool (CLT) for real-time and depth-resolved investigation of soil colors within the visible spectrum. Until now, no routines exist on how to handle high-resolved (mm-scale) soil color data. To develop such a routine, we transform raw data (CIEXYZ) into soil color surrogates of selected color spaces (CIExyY, CIEL*a*b*, CIEL*c*h*, sRGB) and denoise small-scale natural variability by Haar and Daublet4 wavelet transformation, gathering interpretable color logs over depth. However, interpreting color log data as a single application remains challenging. Additional information, such as site-specific knowledge of the geological setting, is required to correlate soil color data to specific layers properties. Hence, we exemplary provide results from a joint interpretation of in situ-obtained soil color data and 'state-of-the-art' direct push based profiling tool data and discuss the benefit of additional data. The developed routine is capable of transferring the provided information obtained as colorimetric data into interpretable color surrogates. Soil color data proved to correlate with small-scale lithological/chemical changes (e.g., grain size, oxidative and reductive conditions), especially when combined with additional direct push vertical high resolution data (e.g., cone penetration testing and soil sampling). Thus, the technique allows enhanced profiling by means of providing another reproducible high-resolution parameter for analysis subsurface conditions. This opens potential new areas of application and new outputs for such data in site investigation. It is our intention to improve color measurements by means method of application and data

  17. Automatic classification of communication logs into implementation stages via text analysis.

    Science.gov (United States)

    Wang, Dingding; Ogihara, Mitsunori; Gallo, Carlos; Villamar, Juan A; Smith, Justin D; Vermeer, Wouter; Cruden, Gracelyn; Benbow, Nanette; Brown, C Hendricks

    2016-09-06

    To improve the quality, quantity, and speed of implementation, careful monitoring of the implementation process is required. However, some health organizations have such limited capacity to collect, organize, and synthesize information relevant to its decision to implement an evidence-based program, the preparation steps necessary for successful program adoption, the fidelity of program delivery, and the sustainment of this program over time. When a large health system implements an evidence-based program across multiple sites, a trained intermediary or broker may provide such monitoring and feedback, but this task is labor intensive and not easily scaled up for large numbers of sites. We present a novel approach to producing an automated system of monitoring implementation stage entrances and exits based on a computational analysis of communication log notes generated by implementation brokers. Potentially discriminating keywords are identified using the definitions of the stages and experts' coding of a portion of the log notes. A machine learning algorithm produces a decision rule to classify remaining, unclassified log notes. We applied this procedure to log notes in the implementation trial of multidimensional treatment foster care in the California 40-county implementation trial (CAL-40) project, using the stages of implementation completion (SIC) measure. We found that a semi-supervised non-negative matrix factorization method accurately identified most stage transitions. Another computational model was built for determining the start and the end of each stage. This automated system demonstrated feasibility in this proof of concept challenge. We provide suggestions on how such a system can be used to improve the speed, quality, quantity, and sustainment of implementation. The innovative methods presented here are not intended to replace the expertise and judgement of an expert rater already in place. Rather, these can be used when human monitoring and

  18. Standardizing effect size from linear regression models with log-transformed variables for meta-analysis.

    Science.gov (United States)

    Rodríguez-Barranco, Miguel; Tobías, Aurelio; Redondo, Daniel; Molina-Portillo, Elena; Sánchez, María José

    2017-03-17

    Meta-analysis is very useful to summarize the effect of a treatment or a risk factor for a given disease. Often studies report results based on log-transformed variables in order to achieve the principal assumptions of a linear regression model. If this is the case for some, but not all studies, the effects need to be homogenized. We derived a set of formulae to transform absolute changes into relative ones, and vice versa, to allow including all results in a meta-analysis. We applied our procedure to all possible combinations of log-transformed independent or dependent variables. We also evaluated it in a simulation based on two variables either normally or asymmetrically distributed. In all the scenarios, and based on different change criteria, the effect size estimated by the derived set of formulae was equivalent to the real effect size. To avoid biased estimates of the effect, this procedure should be used with caution in the case of independent variables with asymmetric distributions that significantly differ from the normal distribution. We illustrate an application of this procedure by an application to a meta-analysis on the potential effects on neurodevelopment in children exposed to arsenic and manganese. The procedure proposed has been shown to be valid and capable of expressing the effect size of a linear regression model based on different change criteria in the variables. Homogenizing the results from different studies beforehand allows them to be combined in a meta-analysis, independently of whether the transformations had been performed on the dependent and/or independent variables.

  19. Standardizing effect size from linear regression models with log-transformed variables for meta-analysis

    Directory of Open Access Journals (Sweden)

    Miguel Rodríguez-Barranco

    2017-03-01

    Full Text Available Abstract Background Meta-analysis is very useful to summarize the effect of a treatment or a risk factor for a given disease. Often studies report results based on log-transformed variables in order to achieve the principal assumptions of a linear regression model. If this is the case for some, but not all studies, the effects need to be homogenized. Methods We derived a set of formulae to transform absolute changes into relative ones, and vice versa, to allow including all results in a meta-analysis. We applied our procedure to all possible combinations of log-transformed independent or dependent variables. We also evaluated it in a simulation based on two variables either normally or asymmetrically distributed. Results In all the scenarios, and based on different change criteria, the effect size estimated by the derived set of formulae was equivalent to the real effect size. To avoid biased estimates of the effect, this procedure should be used with caution in the case of independent variables with asymmetric distributions that significantly differ from the normal distribution. We illustrate an application of this procedure by an application to a meta-analysis on the potential effects on neurodevelopment in children exposed to arsenic and manganese. Conclusions The procedure proposed has been shown to be valid and capable of expressing the effect size of a linear regression model based on different change criteria in the variables. Homogenizing the results from different studies beforehand allows them to be combined in a meta-analysis, independently of whether the transformations had been performed on the dependent and/or independent variables.

  20. Interim analysis based on the weighted log-rank test for delayed treatment effects under staggered patient entry.

    Science.gov (United States)

    Yoshida, Mizuki; Matsuyama, Yutaka

    2016-01-01

    Fleming and Harrington's G(ρ,γ) class of weighted log-rank tests is appropriate for detecting delayed treatment effects such as those seen in cancer vaccines. A conditional power (CP) and an alpha spending function (ASF) approach are useful for interim analyses that are conducted with the aim of early termination due to futility and efficacy, respectively. However, calculation of the CP and the total Type I error probability are often not considered for delayed effects under the staggered patient entry. In this article, we first propose methods for calculating the CP analytically based on the weighted log-rank test. We compared the performances of the proposed methods with two other methods (i.e., usual log-rank test and optimal one) under the delayed alternatives. Our simulations demonstrated that the CP based on the weighted log-rank test was more powerful than that of the usual log-rank test and was comparable to the CP based on the optimal log-rank test. Second, we quantitatively evaluated the degree to which the Type I error probability was inflated when an ASF approach with forced independent increments assumption was applied to the weighted log-rank test. The proposed method will provide valuable tools in the decision-making stage of the interim analysis.

  1. Improved analysis of bacterial CGH data beyond the log-ratio paradigm

    Directory of Open Access Journals (Sweden)

    Aakra Ågot

    2009-03-01

    Full Text Available Abstract Background Existing methods for analyzing bacterial CGH data from two-color arrays are based on log-ratios only, a paradigm inherited from expression studies. We propose an alternative approach, where microarray signals are used in a different way and sequence identity is predicted using a supervised learning approach. Results A data set containing 32 hybridizations of sequenced versus sequenced genomes have been used to test and compare methods. A ROC-analysis has been performed to illustrate the ability to rank probes with respect to Present/Absent calls. Classification into Present and Absent is compared with that of a gaussian mixture model. Conclusion The results indicate our proposed method is an improvement of existing methods with respect to ranking and classification of probes, especially for multi-genome arrays.

  2. Taming Log Files from Game/Simulation-Based Assessments: Data Models and Data Analysis Tools. Research Report. ETS RR-16-10

    Science.gov (United States)

    Hao, Jiangang; Smith, Lawrence; Mislevy, Robert; von Davier, Alina; Bauer, Malcolm

    2016-01-01

    Extracting information efficiently from game/simulation-based assessment (G/SBA) logs requires two things: a well-structured log file and a set of analysis methods. In this report, we propose a generic data model specified as an extensible markup language (XML) schema for the log files of G/SBAs. We also propose a set of analysis methods for…

  3. Interpreting Flow Logs with an Integrated Wellbore Analysis Tool, AnalyzeHOLE

    Science.gov (United States)

    Halford, K. J.; Garcia, C. A.; Laczniak, R. J.

    2008-12-01

    Well construction can significantly alter the relation between changes in fluid velocity and hydraulic conductivity. For example, continuously screened wells can mask strong hydraulic conductivity contrasts between lithologic units, whereas alternating intervals of screen and blank casing can create the appearance of hydraulic-conductivity contrasts throughout a single, nearly homogenous lithologic unit. Rapid fluid- velocity increases can occur near the ends of screened intervals because casing creates convergent flow between aquifer and screen end. These fluid-velocity increases often are misinterpreted as more permeable units by conventional flow-log interpretation. In addition, thin, highly permeable units can be misinterpreted as thicker and less permeable intervals or not identified at all. These conditions compromise standard flow-log interpretation because screened intervals induce vertical flow fields near the wellbore. AnalyzeHOLE, an integrated wellbore analysis tool for simulating flow and transport in wells and aquifer systems, is an effective alternative for simulating and evaluating complex well-aquifer system interaction. In this analysis tool, the pumping well and adjacent aquifer system are simulated with an axisymmetric, radial geometry in a two-dimensional MODFLOW model. Hydraulic conductivities are distributed by depth and estimated with PEST by minimizing squared differences between simulated and measured flows and drawdowns. Hydraulic conductivity can vary within a lithology but variance is limited with regularization. Transmissivity of the simulated system also can be constrained to estimates from single-well tests. Water- quality changes in the production well can be simulated with simple mixing models between zones of differing water quality. These zones are differentiated by backtracking thousands of particles from the well screens with MODPATH. An Excel spreadsheet is used to interface the various components of AnalyzeHOLE by (1

  4. The association in a two-way contingency table through log odds ratio analysis: the case of Sarno river pollution.

    Science.gov (United States)

    Camminatiello, Ida; D'Ambra, Antonello; Sarnacchiaro, Pasquale

    2014-01-01

    In this paper we are proposing a general framework for the analysis of the complete set of log Odds Ratios (ORs) generated by a two-way contingency table. Starting from the RC (M) association model and hypothesizing a Poisson distribution for the counts of the two-way contingency table we are obtaining the weighted Log Ratio Analysis that we are extending to the study of log ORs. Particularly we are obtaining an indirect representation of the log ORs and some synthesis measures. Then for studying the matrix of log ORs we are performing a generalized Singular Value Decomposition that allows us to obtain a direct representation of log ORs. We also expect to get summary measures of association too. We have considered the matrix of complete set of ORs, because, it is linked to the two-way contingency table in terms of variance and it allows us to represent all the ORs on a factorial plan. Finally, a two-way contingency table, which crosses pollution of the Sarno river and sampling points, is to be analyzed to illustrate the proposed framework.

  5. Big Data demonstrator using Hadoop to build a Linux cluster for log data analysis using R

    DEFF Research Database (Denmark)

    Torbensen, Rune Sonnich; Top, Søren

    2017-01-01

    This article walks through the steps to create a Hadoop Linux cluster in the cloud and outlines how to analyze device log data via an example in the R programming language.......This article walks through the steps to create a Hadoop Linux cluster in the cloud and outlines how to analyze device log data via an example in the R programming language....

  6. Analysis of a double steering forest trailer for long wood log transportation

    Directory of Open Access Journals (Sweden)

    Francesco Marinello

    2013-09-01

    Full Text Available A cost effective technical solution of a forest double steering trailer was studied and tested, allowing decrease of radius of curvature and increase of the maneuverability, independently from the length of the transported logs. The steering system improves the so called “stingertype truck” configuration using an articulated frame; through a rearward hinge, the front wheels direction mechanically controls and adapts the direction of rear twin wheels. The study was based on CAD simulations considering the dimensions of the trailer transporting logs with a length up to 12 m. For different log lengths the simulation analyzed the total maneuver area, in terms of minimum curve radius and curve widening. A field test on a prototype operated for transport of long logs along a representative forest road in the Alps was carried out. The results confirm the improvements foreseen by CAD simulations, with allowed curve radius down to 6 m, even with 12 m logs.

  7. Log-Linear Techniques for the Analysis of Categorical Data: A Demonstration with the Myers-Briggs Type Indicator.

    Science.gov (United States)

    Salter, Daniel W.

    2003-01-01

    Log-linear analysis (LLA) techniques for categorical variables are demonstrated and evaluated using data from the Myers-Briggs Type Indicator. Symmetrical LLA and asymmetrical LLA address questions of association and inference, respectively. Configural frequency analysis is examined as a strategy for whole types research. LLA approaches seem…

  8. Analysis of the Data from the Geophysical Borehole Logging on the KURT Site

    International Nuclear Information System (INIS)

    Kim, Kyung Su; Koh, Yong Kwon; Bae, Dae Seok; Kim, Geon Young; Park, Kyung Woo; Ji, Sung Hoon; Ryu, Ji Hun

    2009-08-01

    The properties of rock mass in the deep borehole, which is named DB-1 and installed in KURT site, were analyzed using the resultant data from several geophysical borehole logging methods including BIPS, SPS, full-wave sonic logging, gamma-gamma logging, electrical resistivity survey. From the results, the fracture zones at 154 m and 200-224 m depth in DB-1 was identified. We expected that the results can establish the basic information about the structural geology in and around KURT site

  9. Nuclear and chloroplast microsatellite analysis of Abies sachalinensis regeneration on fallen logs in a subboreal forest in Hokkaido, Japan.

    Science.gov (United States)

    Lian, Chunlan; Goto, Susumu; Kubo, Takuya; Takahashi, Yasuo; Nakagawa, Masahiko; Hogetsu, Taizo

    2008-06-01

    Fallen logs are the main regeneration sites for Abies sachalinensis (Sachalin fir) in subboreal forests in Japan. We surveyed the spatial genetic structure of different demographic stages in a 4.29-ha natural population of A. sachalinensis. Genetic structure was significant at short distances throughout all stages in this wind-dispersed conifer. To evaluate the effects of fallen-log-dependent recruitment on demography and spatial genetic structure, we conducted parentage analysis of offspring with highly polymorphic nuclear simple sequence repeat and chloroplast simple sequence repeat markers, and developed a new hierarchical Bayesian model to estimate the effects of mother trees and fallen logs on seed dispersal and offspring recruitment. Combined application of nuclear and chloroplast simple sequence repeat markers allowed us to unambiguously identify mother trees of most offspring (> 90%). Female reproductive success was extremely skewed; a few adults produced most of the offspring on fallen logs. Limited distance of effective dispersal and recruitment was seen in the parentage analysis and modelling estimation. These recruitment characters of A. sachalinensis, with a fallen-log-dependent recruitment process, may result in significant genetic structure in early demographic stages.

  10. Wireless and wireline service convergence in next generation optical access networks - the FP7 WISCON project

    DEFF Research Database (Denmark)

    Vegas Olmos, Juan José; Pang, Xiaodan; Lebedev, Alexander

    2014-01-01

    . In this paper, we will present the Marie Curie Framework Program 7 project “Wireless and wireline service convergence in next generation optical access networks” (WISCON), which focuses on the conception and study of novel architectures for wavelength-division-multiplexing (WDM) optical multi-modulation format...... radio-over-fiber (RoF) systems; this is a promising solution to implement broadband seamless wireless -wireline access networks. This project successfully concluded in autumn 2013, and is being follow up by another Marie Curie project entitled “flexible edge nodes for dynamic optical interconnection...

  11. Borehole flowmeter logging for the accurate design and analysis of tracer tests.

    Science.gov (United States)

    Basiricò, Stefano; Crosta, Giovanni B; Frattini, Paolo; Villa, Alberto; Godio, Alberto

    2015-04-01

    Tracer tests often give ambiguous interpretations that may be due to the erroneous location of sampling points and/or the lack of flow rate measurements through the sampler. To obtain more reliable tracer test results, we propose a methodology that optimizes the design and analysis of tracer tests in a cross borehole mode by using vertical borehole flow rate measurements. Experiments using this approach, herein defined as the Bh-flow tracer test, have been performed by implementing three sequential steps: (1) single-hole flowmeter test, (2) cross-hole flowmeter test, and (3) tracer test. At the experimental site, core logging, pumping tests, and static water-level measurements were previously carried out to determine stratigraphy, fracture characteristics, and bulk hydraulic conductivity. Single-hole flowmeter testing makes it possible to detect the presence of vertical flows as well as inflow and outflow zones, whereas cross-hole flowmeter testing detects the presence of connections along sets of flow conduits or discontinuities intercepted by boreholes. Finally, the specific pathways and rates of groundwater flow through selected flowpaths are determined by tracer testing. We conclude that the combined use of single and cross-borehole flowmeter tests is fundamental to the formulation of the tracer test strategy and interpretation of the tracer test results. © 2014, National Ground Water Association.

  12. Understanding Academic Information Seeking Habits through Analysis of Web Server Log Files: The Case of the Teachers College Library Website

    Science.gov (United States)

    Asunka, Stephen; Chae, Hui Soo; Hughes, Brian; Natriello, Gary

    2009-01-01

    Transaction logs of user activity on an academic library website were analyzed to determine general usage patterns on the website. This paper reports on insights gained from the analysis, and identifies and discusses issues relating to content access, interface design and general functionality of the website. (Contains 13 figures and 8 tables.)

  13. Remote sensing of selective logging in Amazonia Assessing limitations based on detailed field observations, Landsat ETM+, and textural analysis.

    Science.gov (United States)

    Gregory P. Asner; Michael Keller; Rodrigo Pereira; Johan C. Zweede

    2002-01-01

    We combined a detailed field study of forest canopy damage with calibrated Landsat 7 Enhanced Thematic Mapper Plus (ETM+) reflectance data and texture analysis to assess the sensitivity of basic broadband optical remote sensing to selective logging in Amazonia. Our field study encompassed measurements of ground damage and canopy gap fractions along a chronosequence of...

  14. Benefit/cost analysis for research in geothermal log interpretation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rigby, F.A.; Reardon, P.

    1979-07-01

    Well log interpretation, the process of inferring subsurface geology from geophysical measurements made in boreholes, is the most versatile and direct means available of assessing important physical and structural reservoir properties. Historically, well logging has been developed primarily for use in oil and gas wells, and its application in a different environment such as a geothermal reservoir creates complex problems. Present geothermal development is severely hindered by lack of data. Adaptation of well logging techniques holds the promise of reducing development costs, encouraging investment, and assisting regulatory permitting. Such benefits will translate directly into lower power costs and an increased domestic energy supply. A significant acceleration of geothermal power-on-line is possible plus cost reductions through reduction of drilling failure rate, reduction of average well cost, earlier recognition of bad wells, reduced flow testing, and savings due to provision of better data for regulatory decisions. Net undiscounted benefits in 1979 dollars from improving logging and interpretation in geothermal areas can exceed half a billion dollars in slightly more than a decade, about 300 million of this should be regarded as the potential benefit of the Los Alamos Scientific Laboratory Geothermal Log Interpretation Program or similar research.

  15. Comparison of Quantitative Analysis of Image Logs for Shale Volume and Net to Gross Calculation of a Thinly Laminated Reservoir between VNG-NERGE and LAGIA-EGYPT

    Directory of Open Access Journals (Sweden)

    Ahmed Z. Nooh

    2017-09-01

    The gamma ray log data resolution is considerably lower than the FMI log to reflect accurate lithology changes in thinly bedded reservoirs. It has been found afterthought some calibrations and corrections on the FMI resistivity log, the new processed log is used for clay volume and net to gross calculation of the reservoir, indicating the potential of this log for analysis of thin beds. A comparison between VNG-NERGE, NORTH SEA WELL, NERWING and LAGIA-8, LAGIA, EGYPT indicates the calculation for shale volume at different intervals using FMI tools.

  16. Calibration of a neutron log in partially saturated media. Part II. Error analysis

    International Nuclear Information System (INIS)

    Hearst, J.R.; Kasameyer, P.W.; Dreiling, L.A.

    1981-01-01

    Four sources or error (uncertainty) are studied in water content obtained from neutron logs calibrated in partially saturated media for holes up to 3 m. For this calibration a special facility was built and an algorithm for a commercial epithermal neutron log was developed that obtains water content from count rate, bulk density, and gap between the neutron sonde and the borehole wall. The algorithm contained errors due to the calibration and lack of fit, while the field measurements included uncertainties in the count rate (caused by statistics and a short time constant), gap, and density. There can be inhomogeneity in the material surrounding the borehole. Under normal field conditions the hole-size-corrected water content obtained from such neutron logs can have an uncertainty as large as 15% of its value

  17. Estimation of the non records logs from existing logs using artificial neural networks

    Directory of Open Access Journals (Sweden)

    Mehdi Mohammad Salehi

    2017-12-01

    Full Text Available Finding the information of the hydrocarbon reservoirs from well logs is one of the main objectives of the engineers. But, missing the log records (due to many reasons such as broken instruments, unsuitable borehole and etc. is a major challenge to achieve it. Prediction of the density and resistivity logs (Rt, DT and LLS from the conventional wire-line logs in one of the Iranian southwest oil fields is the main purpose of this study. Multilayer neural network was applied to develop an intelligent predictive model for prediction of the logs. A total of 3000 data sets from 3 wells (A, B and C of the studied field were used. Among them, the data of A, B and C wells were used to constructing and testing the model, respectively. To evaluate the performance of the model, the mean square error (MSE and correlation coefficient (R2 in the test data were calculated. A comparison between the MSE of the proposed model and recently intelligent models shows that the proposed model is more accurate than others. Acceptable accuracy and using conventional well logging data are the highlight advantages of the proposed intelligent model.

  18. 76 FR 11407 - Review of Wireline Competition Bureau Data Practices, Computer III Further Remand Proceedings...

    Science.gov (United States)

    2011-03-02

    ... Docket No. 10-132; FCC 11-15] Review of Wireline Competition Bureau Data Practices, Computer III Further... removal of the narrowband comparably efficient interconnection (CEI) and open network architecture (ONA... track the organization set forth in the NPRM in order to facilitate our internal review process. Initial...

  19. 76 FR 20976 - Wireline Competition Bureau Releases 2011 Annual Telecommunications Reporting Worksheet (FCC Form...

    Science.gov (United States)

    2011-04-14

    ... FURTHER INFORMATION CONTACT: Nicholas Degani, Wireline Competition Bureau, Competition Policy Division, at... revised the Form and instructions to make the process of preparing Form 499-A more user-friendly for... sections. (3) Moving the table used to determine whether a filer is de minimis for universal service...

  20. 47 CFR 1.20007 - Additional assistance capability requirements for wireline, cellular, and PCS telecommunications...

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Additional assistance capability requirements for wireline, cellular, and PCS telecommunications carriers. 1.20007 Section 1.20007 Telecommunication... telecommunications carriers. (a) Definition—(1) Call-identifying information. Call identifying information means...

  1. Reconciling the Log-Linear and Non-Log-Linear Nature of the TSH-Free T4 Relationship: Intra-Individual Analysis of a Large Population.

    Science.gov (United States)

    Rothacker, Karen M; Brown, Suzanne J; Hadlow, Narelle C; Wardrop, Robert; Walsh, John P

    2016-03-01

    The TSH-T4 relationship was thought to be inverse log-linear, but recent cross-sectional studies report a complex, nonlinear relationship; large, intra-individual studies are lacking. Our objective was to analyze the TSH-free T4 relationship within individuals. We analyzed data from 13 379 patients, each with six or more TSH/free T4 measurements and at least a 5-fold difference between individual median TSH and minimum or maximum TSH. Linear and nonlinear regression models of log TSH on free T4 were fitted to data from individuals and goodness of fit compared by likelihood ratio testing. Comparing all models, the linear model achieved best fit in 31% of individuals, followed by quartic (27%), cubic (15%), null (12%), and quadratic (11%) models. After eliminating least favored models (with individuals reassigned to best fitting, available models), the linear model fit best in 42% of participants, quartic in 43%, and null model in 15%. As the number of observations per individual increased, so did the proportion of individuals in whom the linear model achieved best fit, to 66% in those with more than 20 observations. When linear models were applied to all individuals and averaged according to individual median free T4 values, variations in slope and intercept indicated a nonlinear log TSH-free T4 relationship across the population. The log TSH-free T4 relationship appears linear in some individuals and nonlinear in others, but is predominantly linear in those with the largest number of observations. A log-linear relationship within individuals can be reconciled with a non-log-linear relationship in a population.

  2. Annual rainfall statistics for stations in the Top End of Australia: normal and log-normal distribution analysis

    International Nuclear Information System (INIS)

    Vardavas, I.M.

    1992-01-01

    A simple procedure is presented for the statistical analysis of measurement data where the primary concern is the determination of the value corresponding to a specified average exceedance probability. The analysis employs the normal and log-normal frequency distributions together with a χ 2 -test and an error analysis. The error analysis introduces the concept of a counting error criterion, or ζ-test, to test whether the data are sufficient to make the Z 2 -test reliable. The procedure is applied to the analysis of annual rainfall data recorded at stations in the tropical Top End of Australia where the Ranger uranium deposit is situated. 9 refs., 12 tabs., 9 figs

  3. Analysis of multi-species point patterns using multivariate log Gaussian Cox processes

    DEFF Research Database (Denmark)

    Waagepetersen, Rasmus; Guan, Yongtao; Jalilian, Abdollah

    Multivariate log Gaussian Cox processes are flexible models for multivariate point patterns. However, they have so far only been applied in bivariate cases. In this paper we move beyond the bivariate case in order to model multi-species point patterns of tree locations. In particular we address...

  4. Progress in analysis of computed tomography (CT) images of hardwood logs for defect detection

    Science.gov (United States)

    Erol Sarigul; A. Lynn Abbott; Daniel L. Schmoldt

    2003-01-01

    This paper addresses the problem of automatically detecting internal defects in logs using computed tomography (CT) images. The overall purpose is to assist in breakdown optimization. Several studies have shown that the commercial value of resulting boards can be increased substantially if defect locations are known in advance, and if this information is used to make...

  5. Logs Analysis of Adapted Pedagogical Scenarios Generated by a Simulation Serious Game Architecture

    Science.gov (United States)

    Callies, Sophie; Gravel, Mathieu; Beaudry, Eric; Basque, Josianne

    2017-01-01

    This paper presents an architecture designed for simulation serious games, which automatically generates game-based scenarios adapted to learner's learning progression. We present three central modules of the architecture: (1) the learner model, (2) the adaptation module and (3) the logs module. The learner model estimates the progression of the…

  6. Combining Data Warehouse and Data Mining Techniques for Web Log Analysis

    DEFF Research Database (Denmark)

    Pedersen, Torben Bach; Jespersen, Søren; Thorhauge, Jesper

    2008-01-01

    a number of approaches thatcombine data warehousing and data mining techniques in order to analyze Web logs.After introducing the well-known click and session data warehouse (DW) schemas,the chapter presents the subsession schema, which allows fast queries on sequences...

  7. People searching for people: analysis of a people search engine log

    NARCIS (Netherlands)

    Weerkamp, W.; Berendsen, R.; Kovachev, B.; Meij, E.; Balog, K.; de Rijke, M.

    2011-01-01

    Recent years show an increasing interest in vertical search: searching within a particular type of information. Understanding what people search for in these "verticals" gives direction to research and provides pointers for the search engines themselves. In this paper we analyze the search logs of

  8. Analysis and Summary of Historical Dry Well Gamma Logs for S Tank Farm 200 West

    Energy Technology Data Exchange (ETDEWEB)

    MYERS, D.A.

    1999-11-22

    Gross gamma ray logs, recorded from January 1975 through mid-year 1994 as part of the Single-Shell Tank Farm Dry Well Surveillance Program, have been reanalyzed for the S tank farm to locate the presence of mobile radionuclides in the subsurface.

  9. SU-F-T-295: MLCs Performance and Patient-Specific IMRT QA Using Log File Analysis

    International Nuclear Information System (INIS)

    Osman, A; Maalej, N; Jayesh, K; Abdel-Rahman, W

    2016-01-01

    Purpose: To analyze the performance of the multi-leaf collimators (MLCs) from the log files recorded during the intensity modulated radiotherapy (IMRT) treatment and to construct the relative fluence maps and do the gamma analysis to compare the planned and executed MLCs movement. Methods: We developed a program to extract and analyze the data from dynamic log files (dynalog files) generated from sliding window IMRT delivery treatments. The program extracts the planned and executed (actual or delivered) MLCs movement, calculates and compares the relative planned and executed fluences. The fluence maps were used to perform the gamma analysis (with 3% dose difference and 3 mm distance to agreement) for 3 IMR patients. We compared our gamma analysis results with those obtained from portal dose image prediction (PDIP) algorithm performed using the EPID. Results: For 3 different IMRT patient treatments, the maximum difference between the planned and the executed MCLs positions was 1.2 mm. The gamma analysis results of the planned and delivered fluences were in good agreement with the gamma analysis from portal dosimetry. The maximum difference for number of pixels passing the gamma criteria (3%/3mm) was 0.19% with respect to portal dosimetry results. Conclusion: MLC log files can be used to verify the performance of the MLCs. Patientspecific IMRT QA based on MLC movement log files gives similar results to EPID dosimetry results. This promising method for patient-specific IMRT QA is fast, does not require dose measurements in a phantom, can be done before the treatment and for every fraction, and significantly reduces the IMRT workload. The author would like to thank King Fahd University of petroleum and Minerals for the support.

  10. SU-F-T-295: MLCs Performance and Patient-Specific IMRT QA Using Log File Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Osman, A [King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); American University of Biuret Medical Center, Biuret (Lebanon); Maalej, N [King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia); Jayesh, K; Abdel-Rahman, W [King Fahad Specialist Hospital-Dammam, Eastern Province (Saudi Arabia)

    2016-06-15

    Purpose: To analyze the performance of the multi-leaf collimators (MLCs) from the log files recorded during the intensity modulated radiotherapy (IMRT) treatment and to construct the relative fluence maps and do the gamma analysis to compare the planned and executed MLCs movement. Methods: We developed a program to extract and analyze the data from dynamic log files (dynalog files) generated from sliding window IMRT delivery treatments. The program extracts the planned and executed (actual or delivered) MLCs movement, calculates and compares the relative planned and executed fluences. The fluence maps were used to perform the gamma analysis (with 3% dose difference and 3 mm distance to agreement) for 3 IMR patients. We compared our gamma analysis results with those obtained from portal dose image prediction (PDIP) algorithm performed using the EPID. Results: For 3 different IMRT patient treatments, the maximum difference between the planned and the executed MCLs positions was 1.2 mm. The gamma analysis results of the planned and delivered fluences were in good agreement with the gamma analysis from portal dosimetry. The maximum difference for number of pixels passing the gamma criteria (3%/3mm) was 0.19% with respect to portal dosimetry results. Conclusion: MLC log files can be used to verify the performance of the MLCs. Patientspecific IMRT QA based on MLC movement log files gives similar results to EPID dosimetry results. This promising method for patient-specific IMRT QA is fast, does not require dose measurements in a phantom, can be done before the treatment and for every fraction, and significantly reduces the IMRT workload. The author would like to thank King Fahd University of petroleum and Minerals for the support.

  11. Direct potable reuse microbial risk assessment methodology: Sensitivity analysis and application to State log credit allocations.

    Science.gov (United States)

    Soller, Jeffrey A; Eftim, Sorina E; Nappier, Sharon P

    2018-01-01

    Understanding pathogen risks is a critically important consideration in the design of water treatment, particularly for potable reuse projects. As an extension to our published microbial risk assessment methodology to estimate infection risks associated with Direct Potable Reuse (DPR) treatment train unit process combinations, herein, we (1) provide an updated compilation of pathogen density data in raw wastewater and dose-response models; (2) conduct a series of sensitivity analyses to consider potential risk implications using updated data; (3) evaluate the risks associated with log credit allocations in the United States; and (4) identify reference pathogen reductions needed to consistently meet currently applied benchmark risk levels. Sensitivity analyses illustrated changes in cumulative annual risks estimates, the significance of which depends on the pathogen group driving the risk for a given treatment train. For example, updates to norovirus (NoV) raw wastewater values and use of a NoV dose-response approach, capturing the full range of uncertainty, increased risks associated with one of the treatment trains evaluated, but not the other. Additionally, compared to traditional log-credit allocation approaches, our results indicate that the risk methodology provides more nuanced information about how consistently public health benchmarks are achieved. Our results indicate that viruses need to be reduced by 14 logs or more to consistently achieve currently applied benchmark levels of protection associated with DPR. The refined methodology, updated model inputs, and log credit allocation comparisons will be useful to regulators considering DPR projects and design engineers as they consider which unit treatment processes should be employed for particular projects. Published by Elsevier Ltd.

  12. Status of preparation of IAEA handbook on nuclear data for well logging and mineral analysis

    International Nuclear Information System (INIS)

    Kocherov, N.P.

    1990-01-01

    The preliminary scope and contents of the IAEA handbook is presented. The work consists of two tasks: one is the book itself containing graphs, tables and the necessary explanatory texts, the second is a computer tape containing nuclear data: cross-sections, spectra of neutron sources, and decay data for a number of selected isotopes. The data will be supplemented by a number of codes to process cross section data. The need of covariance information is discussed and some doubts are raised about the benefits of using this kind of information in treating well logging data

  13. Mathematical model of gamma-ray spectrometry borehole logging for quantitative analysis

    Science.gov (United States)

    Schimschal, Ulrich

    1981-01-01

    A technique for analyzing gamma-ray spectral-logging data has been developed, in which a digital computer is used to calculate the effects of gamma-ray attentuation in a borehole environment. The computer model allows for the calculation of the effects of lithology, porosity, density, and the thickness of a horizontal layer of uniformly distributed radioactive material surrounding a centralized probe in a cylindrical borehole. The computer program also contains parameters for the calculation of the effects of well casing, drilling fluid, probe housing, and losses through the sodium-iodide crystal. Errors associated with the commonly used mathematical assumption of a point detector are eliminated in this model. (USGS)

  14. Precision pressure/temperature logging tool

    Energy Technology Data Exchange (ETDEWEB)

    Henfling, J.A.; Normann, R.A.

    1998-01-01

    Past memory logging tools have provided excellent pressure/temperature data when used in a geothermal environment, and they are easier to maintain and deploy than tools requiring an electric wireline connection to the surface. However, they are deficient since the tool operator is unaware of downhole conditions that could require changes in the logging program. Tools that make ``decisions`` based on preprogrammed scenarios can partially overcome this difficulty, and a suite of such memory tools has been developed at Sandia National Laboratories. The first tool, which forms the basis for future instruments, measures pressure and temperature. Design considerations include a minimization of cost while insuring quality data, size compatibility with diamond-cored holes, operation in holes to 425 C (800 F), transportability by ordinary passenger air service, and ease of operation. This report documents the development and construction of the pressure/temperature tool. It includes: (1) description of the major components; (2) calibration; (3) typical logging scenario; (4) tool data examples; and (5) conclusions. The mechanical and electrical drawings, along with the tool`s software, will be furnished upon request.

  15. Linking downhole logging data and clay mineralogy analysis in the ICDP Lake Junín drilling Project, Peru

    Science.gov (United States)

    Pierdominici, S.; Schleicher, A.; Kueck, J.; Rodbell, D. T.; Abbott, M. B.

    2017-12-01

    The lake Junin drilling project, co-funded by the International Continental Drilling Program (ICDP), is located at 4000 m a.s.l. in the tropical Andes of Peru. Several boreholes were drilled with the goal to obtain both high-resolution paleoclimate records from lacustrine sediments and to reconstruct the history of the continental records covering the glacial-interglacial cycles. Lake Junín is characterized by a thick package of lacustrine sediments (> 125 m) deposited at a high rate (0.2 to 1.0 mm yr-1), and it is one of the few lakes in the tropical Andes that is hundreds of thousands of years old with a continuous sedimentation rate preserving a very long and continuous record of past ice age cycles. The boreholes reached a maximum depth of 110.08 m and continuous coring was performed at three sites with 11 boreholes. Additionally, an extensive geophysical downhole logging campaign was performed on five boreholes (1A, 1C, 1D, 2A and 3B) by the Operational Support Group of ICDP. Downhole logging measurements comprise total and spectrum gamma ray, magnetic susceptibility, borehole geometry, temperature, and sonic p-wave velocity. In order to fit the downhole logging depths to the composite profile depths, each borehole was depth-matched with the core data. Interpreting the downhole logging data permits to establish a complete lithological log, to characterize the in-situ physical properties of drilled lacustrine sediments, to determine sedimentary structures and to obtain evidences about palaeoclimatic conditions during up to 200 ka. Th and K values are used as a proxy for a first estimate and characterization of clay content in the sediments, which are present as montmorillonite, smectite, illite, and kaolinite in different amounts. Linking the clay minerals that occur in the core material with the downhole logging data allows assessing the geological history of the lake and the relationship to climate change processes. Additional laboratory analysis will be

  16. Cores, logs and tests

    International Nuclear Information System (INIS)

    Johnson, C.A. Jr.

    1983-01-01

    A general overview is given of well logging procedures used in the exploration and production of oil and gas wells. Techniques include γ logging, neutron logging, caliper logging, resistivity logging, temperature logging, and production logging. Typical logs are shown for some techniques

  17. The application of moment methods to the analysis of fluid electrical conductivity logs in boreholes

    International Nuclear Information System (INIS)

    Loew, S.; Tsang, Chin-Fu; Hale, F.V.; Hufschmied, P.

    1990-08-01

    This report is one of a series documenting the results of the Nagra-DOE Cooperative (NDC-I) research program in which the cooperating scientists explore the geological, geophysical, hydrological, geochemical, and structural effects anticipated from the use of a rock mass as a geologic repository for nuclear waste. Previous reports have presented a procedure for analyzing a time sequence of wellbore electric conductivity logs in order to obtain outflow parameters of fractures intercepted by the borehole, and a code, called BORE, used to simulate borehole fluid conductivity profiles given these parameters. The present report describes three new direct (not iterative) methods for analyzing a short time series of electric conductivity logs based on moment quantities of the individual outflow peaks and applies them to synthetic as well as to field data. The results of the methods discussed show promising results and are discussed in terms of their respective advantages and limitations. In particular it is shown that one of these methods, the so-called ''Partial Moment Method,'' is capable of reproducing packer test results from field experiments in the Leuggern deep well within a factor of three, which is below the range of what is recognized as the precision of packer tests themselves. Furthermore the new method is much quicker than the previously used iterative fitting procedure and is even capable of handling transient fracture outflow conditions. 20 refs., 11 figs., 10 tabs

  18. Fast neutron (14 MeV) attenuation analysis in saturated core samples and its application in well logging

    International Nuclear Information System (INIS)

    Amin Attarzadeh; Mohammad Kamal Ghassem Al Askari; Tagy Bayat

    2009-01-01

    To introduce the application of nuclear logging, it is appropriate to provide a motivation for the use of nuclear measurement techniques in well logging. Importance aspects of the geological sciences are for instance grain and porosity structure and porosity volume of the rocks, as well as the transport properties of a fluid in the porous media. Nuclear measurements are, as a rule non-intrusive. Namely, a measurement does not destroy the sample, and it does not interfere with the process to be measured. Also, non- intrusive measurements are often much faster than the radiation methods, and can also be applied in field measurements. A common type of nuclear measurement employs neutron irradiation. It is powerful technique for geophysical analysis. In this research we illustrate the detail of this technique and it's applications to well logging and oil industry. Experiments have been performed to investigate the possibilities of using neutron attenuation measurements to determine water and oil content of rock sample. A beam of 14 MeV neutrons produced by a 150 KV neutron generator was attenuated by different samples and subsequently detected with plastic scintillators NE102 (Fast counter). Each sample was saturated with water and oil. The difference in neutron attenuation between dry and wet samples was compared with the fluid content determined by mass balance of the sample. In this experiment we were able to determine 3% of humidity in standard sample model (SiO 2 ) and estimate porosity in geological samples when saturated with different fluids. (Author)

  19. SU-C-BRD-03: Analysis of Accelerator Generated Text Logs for Preemptive Maintenance

    International Nuclear Information System (INIS)

    Able, CM; Baydush, AH; Nguyen, C; Munley, MT; Gersh, J; Ndlovu, A; Rebo, I; Booth, J; Perez, M; Sintay, B

    2014-01-01

    Purpose: To develop a model to analyze medical accelerator generated parameter and performance data that will provide an early warning of performance degradation and impending component failure. Methods: A robust 6 MV VMAT quality assurance treatment delivery was used to test the constancy of accelerator performance. The generated text log files were decoded and analyzed using statistical process control (SPC) methodology. The text file data is a single snapshot of energy specific and overall systems parameters. A total of 36 system parameters were monitored which include RF generation, electron gun control, energy control, beam uniformity control, DC voltage generation, and cooling systems. The parameters were analyzed using Individual and Moving Range (I/MR) charts. The chart limits were calculated using a hybrid technique that included the use of the standard 3σ limits and the parameter/system specification. Synthetic errors/changes were introduced to determine the initial effectiveness of I/MR charts in detecting relevant changes in operating parameters. The magnitude of the synthetic errors/changes was based on: the value of 1 standard deviation from the mean operating parameter of 483 TB systems, a small fraction (≤ 5%) of the operating range, or a fraction of the minor fault deviation. Results: There were 34 parameters in which synthetic errors were introduced. There were 2 parameters (radial position steering coil, and positive 24V DC) in which the errors did not exceed the limit of the I/MR chart. The I chart limit was exceeded for all of the remaining parameters (94.2%). The MR chart limit was exceeded in 29 of the 32 parameters (85.3%) in which the I chart limit was exceeded. Conclusion: Statistical process control I/MR evaluation of text log file parameters may be effective in providing an early warning of performance degradation or component failure for digital medical accelerator systems. Research is Supported by Varian Medical Systems, Inc

  20. Getting to the Source: a Survey of Quantitative Data Sources Available to the Everyday Librarian: Part 1: Web Server Log Analysis

    Directory of Open Access Journals (Sweden)

    Lisa Goddard

    2007-03-01

    Full Text Available This is the first part of a two‐part article that provides a survey of data sources which are likely to be immediately available to the typical practitioner who wishes to engage instatistical analysis of collections and services within his or her own library. Part I outlines the data elements which can be extracted from web server logs, and discusses web log analysis tools. Part II looks at logs, reports, and data sources from proxy servers, resource vendors, link resolvers, federated search engines, institutional repositories, electronic reference services, and the integrated library system.

  1. Reservoir characterization utilizing the well logging analysis of Abu Madi Formation, Nile Delta, Egypt

    Directory of Open Access Journals (Sweden)

    M. Mahmoud

    2017-09-01

    Full Text Available The petrophysical evaluation of the Late Miocene Abu Madi Formation were accomplished based on the open hole logs of eighteen wells in Abu Madi–El Qar’a gas fields, onshore Nile Delta, Egypt. The lithological contents of this rock unit were analyzed using the cross plots of petrophysical parameters including shale volume, porosity and hydrocarbon saturation. The neutron /density cross-plots, M-N and RHOMAA–DTMAA and litho-saturation cross plots of the studied wells show that the main lithology of the lower part of Abu Madi Formation is calcareous sandstones with shale intercalations in most of the studied wells while its lithology is mainly shale with sand intercalations in wells AM-13, AM-21 and AM-7. The lithology of the upper part of Abu Madi Formation in most wells is composed mainly of shale while its lithology in AM-13, AM-21 and AM-7 wells is composed of sandstone with shale intercalations. The thorium-potassium cross plots indicate that, Abu Madi Formation was deposited mostly in fluvial to shallow marine environments according to the presence of mica and illite in the southern area and montmorillonite at the northern area as dominant clay minerals. Contour maps of several petrophysical parameters such as effective thickness, average shale volume, average porosity and hydrocarbon saturation showed that both lower and upper parts of Abu Madi Formation in the study area have promising reservoirs characteristics; in which the prospective area for gas accumulation located toward the central part.

  2. Geophysical log analysis of selected test and residential wells at the Shenandoah Road National Superfund Site, East Fishkill, Dutchess County, New York

    Science.gov (United States)

    Reynolds, Richard J.; Anderson, J. Alton; Williams, John H.

    2015-01-01

    The U.S. Geological Survey collected and analyzed geophysical logs from 20 test wells and 23 residential wells at the Shenandoah Road National Superfund Site in East Fishkill, New York, from 2006 through 2010 as part of an Interagency Agreement to provide hydrogeologic technical support to the U.S. Environmental Protection Agency, Region 2. The geophysical logs collected include caliper, gamma, acoustic and optical televiewer, deviation, electromagnetic-induction, magnetic-susceptibility, fluid-property, and flow under ambient and pumped conditions. The geophysical logs were analyzed along with single-well aquifer test data and drilling logs to characterize the lithology, fabric, fractures, and flow zones penetrated by the wells. The results of the geophysical log analysis were used as part of the hydrogeologic characterization of the site and in the design of discrete-zone monitoring installations in the test wells and selected residential wells.

  3. Seismic - Wireline logs sequence stratigraphic analyses and geologic evolution for the Upper Cretaceous succession of Abu Gharadig basin, Egypt

    Science.gov (United States)

    Sarhan, Mohammad Abdelfattah

    2017-05-01

    The Upper Cretaceous megasequence in the northern part of the Egyptian Western Desert has been classified into four 2nd order depositional sequences. These sequences started with the Cenomanian SQ-I topped by the Turonian - Santonian SQ-II. However, both SQ-III and SQ-IV represent the Campanian- Maastrichtian time span. The interpreted 2nd order SQ-I and SQ-II have been further subdivided into six smaller 3rd order sequences (SQ-1 to SQ-6). The depositional history started during the Early Cenomanian times, characterized by wide marine invasion enabled the deposition of the shallow marine Bahariya Formation (SQ-1). The Upper Cenomanian times, witnessed a rapid subsidence, simultaneously with new marine transgressive phase. This is resulted in the deposition of SQ-2, consuming the entire sediments of the Abu Roash G Member. During the Turonian - Coniacian times the northern parts of Egypt showed successive oscillating transgressive - regressive marine cycles led to equivocal sedimentary bodies of the Turonian-Coniacian Abu Roash Formation (SQ-3, SQ-4, and SQ-5). During the Santonian age, the northern parts of Egypt were subjected to tectonic crustal shortening, producing large scale folds. As a result, a new tectonically-overprinted marine depositional cycle started and marked by rapid phase of basin subsidence. This was accompanied by a deep marine invasion covered most of the northern parts of Egyptian lands, depositing the lower parts of the Khoman- B (SQ-6) under transgressive depositional conditions. By the end of Santonian cycle, the upper parts of the Khoman Formation B Member was deposited during a gradual, and slow relative sea level drop ending the deposition of SQ-6. At the beginning of the Campanian - Maastrichtian times, a new widespread sea-level rise associated with basin subsidence. Accordingly, two successive depositional cycles were thus initiated, forming SQ-III and SQ-VI sequences separated by unconformity type-2 boundary (SB-8).

  4. Logging-while-drilling and wireline velocities: Site NGHP-01-10, Krishna-Godavari Basin, India

    Digital Repository Service at National Institute of Oceanography (India)

    Jaiswal, P.; Al-Bulushi, S.; Dewangan, P.

    could present more steady-state periods of fracture growth, where fluid and hydrate could be existing separately in the fractures. Despite the obvious presence of fracture, we have demonstrated an isotropic rock model. However, we do not intend... 7841 1. Boone Pickens School of Geology, Oklahoma State University, Stillwater, Oklahoma 74078, USA 2. CSIR-National Institute of Oceanography, Dona Paula, Goa, 403004, India Abstract: At site NGHP-01-10, Krishna-Godavari Basin, India...

  5. Improving log transportation with data based monitoring and analysis in northern Wisconsin and upper peninsula of Michigan.

    Science.gov (United States)

    2012-02-01

    Minimizing transportation cost is essential in the forest products industry. Logs and wood chips are relatively low value. Logs are a dense heavy weight product to transport, while chips are light and bulky. These handling characteristics along with ...

  6. Dewarless Logging Tool - 1st Generation

    Energy Technology Data Exchange (ETDEWEB)

    HENFLING,JOSEPH A.; NORMANN,RANDY A.

    2000-08-01

    This report focuses on Sandia National Laboratories' effort to create high-temperature logging tools for geothermal applications without the need for heat shielding. One of the mechanisms for failure in conventional downhole tools is temperature. They can only survive a limited number of hours in high temperature environments. For the first time since the evolution of integrated circuits, components are now commercially available that are qualified to 225 C with many continuing to work up to 300 C. These components are primarily based on Silicon-On-Insulator (SOI) technology. Sandia has developed and tested a simple data logger based on this technology that operates up to 300 C with a few limiting components operating to only 250 C without thermal protection. An actual well log to 240 C without shielding is discussed. The first prototype high-temperature tool measures pressure and temperature using a wire-line for power and communication. The tool is based around the HT83C51 microcontroller. A brief discussion of the background and status of the High Temperature Instrumentation program at Sandia, objectives, data logger development, and future project plans are given.

  7. Structural equation and log-linear modeling: a comparison of methods in the analysis of a study on caregivers' health

    Directory of Open Access Journals (Sweden)

    Rosenbaum Peter L

    2006-10-01

    Full Text Available Abstract Background In this paper we compare the results in an analysis of determinants of caregivers' health derived from two approaches, a structural equation model and a log-linear model, using the same data set. Methods The data were collected from a cross-sectional population-based sample of 468 families in Ontario, Canada who had a child with cerebral palsy (CP. The self-completed questionnaires and the home-based interviews used in this study included scales reflecting socio-economic status, child and caregiver characteristics, and the physical and psychological well-being of the caregivers. Both analytic models were used to evaluate the relationships between child behaviour, caregiving demands, coping factors, and the well-being of primary caregivers of children with CP. Results The results were compared, together with an assessment of the positive and negative aspects of each approach, including their practical and conceptual implications. Conclusion No important differences were found in the substantive conclusions of the two analyses. The broad confirmation of the Structural Equation Modeling (SEM results by the Log-linear Modeling (LLM provided some reassurance that the SEM had been adequately specified, and that it broadly fitted the data.

  8. Multivariate Analysis of Physical and Elastic Properties in Sandstones, Measured in Laboratory and Compare to Well Logs

    Science.gov (United States)

    Akarapatima, T.; Prasad, M.

    2017-12-01

    Sedimentary basins that include hydrocarbon reservoirs are composed of sandstones and shaly sandstones. Rock properties are investigated, because physical properties can directly tell the reservoir performance and can be implied from the acoustic properties. Thus, modeling the relation of rock properties is another way to identify the reservoirs and predict their efficiency. The previous studies have shown that wave velocities in rock samples can be expressed as a co-linear relation between porosity and clay content when the experimental pressure is sufficient to close internal cracks/closure. So, this research focuses on modeling the empirical multivariate linear regressions of velocities. METHOD: Physical and elastic rock properties are gathered from published rockphysics papers. The samples vary in locations, and widely range in porosity and clay content. Then a rockphysics analysis along with two statistical methods: principal component analysis (PCA) and multivariate regression analysis are performed to get the linear regression equations of Vp, Vs. RESULTS: The acoustic properties depend on many physical properties; however, only porosity (Φ) and mineral composition of the rocks are significant. The regression models are linear as suggested by the previous studies. Vp = 5.58 - 7.10(Φ) - 1.99(clay) R2 = 0.85, Vs = 3.54 - 4.72(Φ) - 2.01(clay) R2 = 0.83. Two factors are involved in the velocity changes: porosity and mineral compositions. The porosity effect is approximately 3.5 and 2 times higher than the clay content effect on Vp and Vs, respectively. The presence of carbonate and pyrite in samples also emphasizes a mineral effect, because their estimated velocities are under-predicted. Therefore, the explorations can use these velocity models to confirm the accuracy of collected velocities from well logs or predict velocities in a case of data missing since the well log operations can bring in velocity measurement errors from well damages or uncomplete

  9. Auto-Gopher-II: an autonomous wireline rotary-hammer ultrasonic drill

    Science.gov (United States)

    Badescu, Mircea; Lee, Hyeong Jae; Sherrit, Stewart; Bao, Xiaoqi; Bar-Cohen, Yoseph; Jackson, Shannon; Chesin, Jacob; Zacny, Kris; Paulsen, Gale L.; Mellerowicz, Bolek; Kim, Daniel

    2017-04-01

    Developing technologies that would enable future NASA exploration missions to penetrate deeper into the subsurface of planetary bodies for sample collection is of great importance. Performing these tasks while using minimal mass/volume systems and with low energy consumption is another set of requirements imposed on such technologies. A deep drill, called Auto-Gopher II, is currently being developed as a joint effort between JPL's NDEAA laboratory and Honeybee Robotics Corp. The Auto-Gopher II is a wireline rotary-hammer drill that combines formation breaking by hammering using an ultrasonic actuator and cuttings removal by rotating a fluted auger bit. The hammering mechanism is based on the Ultrasonic/Sonic Drill/Corer (USDC) mechanism that has been developed as an adaptable tool for many drilling and coring applications. The USDC uses an intermediate free-flying mass to transform high frequency vibrations of a piezoelectric transducer horn tip into sonic hammering of the drill bit. The USDC concept was used in a previous task to develop an Ultrasonic/Sonic Ice Gopher and then integrated into a rotary hammer device to develop the Auto-Gopher-I. The lessons learned from these developments are being integrated into the development of the Auto- Gopher-II, an autonomous deep wireline drill with integrated cuttings and sample management and drive electronics. Subsystems of the wireline drill are being developed in parallel at JPL and Honeybee Robotics Ltd. This paper presents the development efforts of the piezoelectric actuator, cuttings removal and retention flutes and drive electronics.

  10. Towards convergence of wireless and wireline signal transport in broadband access networks

    DEFF Research Database (Denmark)

    Yu, Xianbin; Prince, Kamau; Tafur Monroy, Idelfonso

    2010-01-01

    Hybrid optical wireless access networks are to play an important role in the realization of the vision of delivery of broadband services to the end-user any time, anywhere and at affordable costs. We present results of experiments conducted over a field deployed optical fibre links we successfull...... demonstrated converged wireless and wireline signal transport over a common fibre infrastructure. The type of signal used in this field deployed experiments cover WiMax, Impulse-radio ultra-wideband (UWB) and coherent transmission of baseband QPSK and radio-over-fibre signals....

  11. Understanding the usage of content in a mental health intervention for depression: an analysis of log data.

    Science.gov (United States)

    Van Gemert-Pijnen, Julia Ewc; Kelders, Saskia M; Bohlmeijer, Ernst T

    2014-01-31

    Web-based interventions for the early treatment of depressive symptoms can be considered effective in reducing mental complaints. However, there is a limited understanding of which elements in an intervention contribute to effectiveness. For efficiency and effectiveness of interventions, insight is needed into the use of content and persuasive features. The aims of this study were (1) to illustrate how log data can be used to understand the uptake of the content of a Web-based intervention that is based on the acceptance and commitment therapy (ACT) and (2) to discover how log data can be of value for improving the incorporation of content in Web-based interventions. Data from 206 participants (out of the 239) who started the first nine lessons of the Web-based intervention, Living to the Full, were used for a secondary analysis of a subset of the log data of the parent study about adherence to the intervention. The log files used in this study were per lesson: login, start mindfulness, download mindfulness, view success story, view feedback message, start multimedia, turn on text-message coach, turn off text-message coach, and view text message. Differences in usage between lessons were explored with repeated measures ANOVAs (analysis of variance). Differences between groups were explored with one-way ANOVAs. To explore the possible predictive value of the login per lesson quartiles on the outcome measures, four linear regressions were used with login quartiles as predictor and with the outcome measures (Center for Epidemiologic Studies-Depression [CES-D] and the Hospital Anxiety and Depression Scale-Anxiety [HADS-A] on post-intervention and follow-up) as dependent variables. A significant decrease in logins and in the use of content and persuasive features over time was observed. The usage of features varied significantly during the treatment process. The usage of persuasive features increased during the third part of the ACT (commitment to value-based living

  12. 78 FR 42699 - Application for Review of a Decision of the Wireline Competition Bureau by Dooly County School...

    Science.gov (United States)

    2013-07-17

    ..., in April 2003, the Commission released the Schools and Libraries Second Report and Order, 68 FR 36931... Commission to 60 days. The Schools and Libraries Second Report and Order did not, however, address the...] Application for Review of a Decision of the Wireline Competition Bureau by Dooly County School System; Schools...

  13. Application of MRIL-WD (Magnetic Resonance Imaging Logging While Drilling) for irreducible water saturation, total reservoir, free-fluid, bound-fluid porosity measurements and its value for the petrophysical analysis of RT/RM data from the Shah Deniz well

    Science.gov (United States)

    Amirov, Elnur

    2016-04-01

    , preferably while the drilling of the brand new wells (logging-while-drilling, LWD). The MRIL-WD Tool can accomplish any tasks reliably and in a timely manner thus saving drilling time and reducing the overall risk for the well. Control of water production and identification of pay zones with high irreducible water saturation are also very important for formation evaluation and petrophysical analysis in oil fields located in the Azerbaijan Republic and also other fields around the world. Sometimes above-mentioned problems can cause delay in completion decisions which will create additional expenses for field management. In many wells, breakthroughs in reservoir characterization have been achieved in directly determining hydrocarbon volumes, net permeability thickness, and hydrocarbon type, thus circumventing the problems associated with obtaining wireline data and the considerable amount of rig time required (so MRIL-WD can considerably reduce the NPT). Some reservoir zones with relatively low water saturation, which calculated from the other conventional logs, can produce with relatively high percentage of water cut, primarily because much of the water is movable. However, other zones with high calculated water saturation produce water free hydrocarbons. The difficulty in predicting water production can be related with the producing from the complex lithology, which can contain low-permeability, medium- to fine-grained shaly sands. Where grains are small, the formations have high surface to volume ratios that result in high irreducible water saturation and due to this we can see low resistivity values. As a result the use of resistivity logs as pay indicator, sometimes can cause low resistivity pay zones might be overlooked and consequently net field pay could be underestimated. In the last few years, nuclear magnetic resonance logs have shown great promise in solving problems of formation evaluation that could not be directly resolved with conventional logs. The capability

  14. Binary Logistic Regression Analysis for Detecting Differential Item Functioning: Effectiveness of R[superscript 2] and Delta Log Odds Ratio Effect Size Measures

    Science.gov (United States)

    Hidalgo, Mª Dolores; Gómez-Benito, Juana; Zumbo, Bruno D.

    2014-01-01

    The authors analyze the effectiveness of the R[superscript 2] and delta log odds ratio effect size measures when using logistic regression analysis to detect differential item functioning (DIF) in dichotomous items. A simulation study was carried out, and the Type I error rate and power estimates under conditions in which only statistical testing…

  15. Holocene tree-line variability in the Kauner Valley, Central Eastern Alps, indicated by dendrochronological analysis of living trees and subfossil logs

    NARCIS (Netherlands)

    Nicolussi, Kurt; Kaufmann, Matthias; Patzelt, Gernot; van der Plicht, Johannes; Thurner, Andrea

    2005-01-01

    The altitude of the Alpine tree-line has often been used as proxy for the climatic conditions in the Holocene epoch. The usual approach for establishing a record for this proxy is the analysis of pollen and macro remains. We analysed living trees and subfossil logs from the timberline ecotone in the

  16. Evaluation of the efficiency and effectiveness of independent dose calculation followed by machine log file analysis against conventional measurement based IMRT QA.

    Science.gov (United States)

    Sun, Baozhou; Rangaraj, Dharanipathy; Boddu, Sunita; Goddu, Murty; Yang, Deshan; Palaniswaamy, Geethpriya; Yaddanapudi, Sridhar; Wooten, Omar; Mutic, Sasa

    2012-09-06

    Experimental methods are commonly used for patient-specific IMRT delivery verification. There are a variety of IMRT QA techniques which have been proposed and clinically used with a common understanding that not one single method can detect all possible errors. The aim of this work was to compare the efficiency and effectiveness of independent dose calculation followed by machine log file analysis to conventional measurement-based methods in detecting errors in IMRT delivery. Sixteen IMRT treatment plans (5 head-and-neck, 3 rectum, 3 breast, and 5 prostate plans) created with a commercial treatment planning system (TPS) were recalculated on a QA phantom. All treatment plans underwent ion chamber (IC) and 2D diode array measurements. The same set of plans was also recomputed with another commercial treatment planning system and the two sets of calculations were compared. The deviations between dosimetric measurements and independent dose calculation were evaluated. The comparisons included evaluations of DVHs and point doses calculated by the two TPS systems. Machine log files were captured during pretreatment composite point dose measurements and analyzed to verify data transfer and performance of the delivery machine. Average deviation between IC measurements and point dose calculations with the two TPSs for head-and-neck plans were 1.2 ± 1.3% and 1.4 ± 1.6%, respectively. For 2D diode array measurements, the mean gamma value with 3% dose difference and 3 mm distance-to-agreement was within 1.5% for 13 of 16 plans. The mean 3D dose differences calculated from two TPSs were within 3% for head-and-neck cases and within 2% for other plans. The machine log file analysis showed that the gantry angle, jaw position, collimator angle, and MUs were consistent as planned, and maximal MLC position error was less than 0.5 mm. The independent dose calculation followed by the machine log analysis takes an average 47 ± 6 minutes, while the experimental approach (using IC and

  17. Rock physics template (RPT) analysis of well logs and seismic data for lithology and fluid classification in Cambay Basin

    Science.gov (United States)

    Datta Gupta, Saurabh; Chatterjee, Rima; Farooqui, M. Y.

    2012-07-01

    The Cambay Basin is 450-km-long north-south-trending graben with an average width of 50 km, having maximum depth of about 7 km. The origin of the Cambay and other Basins on the western margin of India are related to the break up of the Gondwana super-continent in the Late-Triassic to Early-Jurassic (215 ma). The structural disposition of the Pre-Cambrian basement—a complex of igneous and metamorphic rocks exposed in the vicinity of the Cambay Basin—controls its architecture. The principal lineaments in the Basin are aligned towards NE-SE, ENE-WSW and NNW-SSE, respectively. Rock physics templates (RPTs) are charts and graphs generated by using rock physics models, constrained by local geology, that serve as tools for lithology and fluid differentiation. RPT can act as a powerful tool in validating hydrocarbon anomalies in undrilled areas and assist in seismic interpretation and prospect evaluation. However, the success of RPT analysis depends on the availability of the local geological information and the use of the proper model. RPT analysis has been performed on well logs and seismic data of a particular study area in mid Cambay Basin. Rock physics diagnostic approach is adopted in the study area placed at mid Cambay Basin to estimate the volume in the reservoir sands from 6 wells (namely; A, B, C, D, E and F) where oil was already encountered in one well, D. In the study area, hydrocarbon prospective zone has been marked through compressional (P wave) and shear wave (S wave) impedance only. In the RPT analysis, we have plotted different kinds of graphical responses of Lame's parameters, which are the function of P-wave velocity, S-wave velocity and density. The discrete thin sand reservoirs have been delineated through the RPT analysis. The reservoir pay sand thickness map of the study area has also been derived from RPT analysis and fluid characterization. Through this fluid characterization, oil-bearing thin sand layers have been found in well E including

  18. A wireline piston core barrel for sampling cohesionless sand and gravel below the water table

    Science.gov (United States)

    Zapico, Michael M.; Vales, Samuel; Cherry, John A.

    1987-01-01

    A coring device has been developed to obtain long and minimally disturbed samples of saturated cohesionless sand and gravel. The coring device, which includes a wireline and piston, was developed specifically for use during hollow-stem auger drilling but it also offers possibilities for cable tool and rotary drilling. The core barrel consists of an inner liner made of inexpensive aluminum or plastic tubing, a piston for core recovery, and an exterior steel housing that protects the liner when the core barrel is driven into the aquifer. The core barrel, which is approximately 1.6m (5.6 feet) long, is advanced ahead of the lead auger by hammering at the surface on drill rods that are attached to the core barrel. After the sampler has been driven 1.5m (5 feet), the drill rods are detached and a wireline is used to hoist the core barrel, with the sample contained in the aluminum or plastic liner, to the surface. A vacuum developed by the piston during the coring operation provides good recovery of both the sediment and aquifer fluids contained in the sediment. In the field the sample tubes can be easily split along their length for on-site inspection or they can be capped with the pore water fluids inside and transported to the laboratory. The cores are 5cm (2 inches) in diameter by 1.5m (5 feet) long. Core acquisition to depths of 35m (115 feet), with a recovery greater than 90 percent, has become routine in University of Waterloo aquifer studies. A large diameter (12.7cm [5 inch]) version has also been used successfully. Nearly continuous sample sequences from sand and gravel aquifers have been obtained for studies of sedimentology, hydraulic conductivity, hydrogeochemistry and microbiology.

  19. Auto-Gopher: A Wire-Line Rotary-Hammer Ultrasonic Drill

    Science.gov (United States)

    Badescu, Mircea; Sherrit, Stewart; Bao, Xiaogi; Bar-Cohen, Yoseph; Chen, Beck

    2011-01-01

    Developing technologies that would enable NASA to sample rock, soil, and ice by coring, drilling or abrading at a significant depth is of great importance for a large number of in-situ exploration missions as well as for earth applications. Proven techniques to sample Mars subsurface will be critical for future NASA astrobiology missions that will search for records of past and present life on the planet, as well as, the search for water and other resources. A deep corer, called Auto-Gopher, is currently being developed as a joint effort of the JPL's NDEAA laboratory and Honeybee Robotics Corp. The Auto-Gopher is a wire-line rotary-hammer drill that combines rock breaking by hammering using an ultrasonic actuator and cuttings removal by rotating a fluted bit. The hammering mechanism is based on the Ultrasonic/Sonic Drill/Corer (USDC) that has been developed as an adaptable tool for many of drilling and coring applications. The USDC uses an intermediate free-flying mass to transform the high frequency vibrations of the horn tip into a sonic hammering of a drill bit. The USDC concept was used in a previous task to develop an Ultrasonic/Sonic Ice Gopher. The lessons learned from testing the ice gopher were implemented into the design of the Auto-Gopher by inducing a rotary motion onto the fluted coring bit. A wire-line version of such a system would allow penetration of significant depth without a large increase in mass. A laboratory version of the corer was developed in the NDEAA lab to determine the design and drive parameters of the integrated system. The design configuration lab version of the design and fabrication and preliminary testing results are presented in this paper

  20. How log-normal is your country? An analysis of the statistical distribution of the exported volumes of products

    Science.gov (United States)

    Annunziata, Mario Alberto; Petri, Alberto; Pontuale, Giorgio; Zaccaria, Andrea

    2016-10-01

    We have considered the statistical distributions of the volumes of 1131 products exported by 148 countries. We have found that the form of these distributions is not unique but heavily depends on the level of development of the nation, as expressed by macroeconomic indicators like GDP, GDP per capita, total export and a recently introduced measure for countries' economic complexity called fitness. We have identified three major classes: a) an incomplete log-normal shape, truncated on the left side, for the less developed countries, b) a complete log-normal, with a wider range of volumes, for nations characterized by intermediate economy, and c) a strongly asymmetric shape for countries with a high degree of development. Finally, the log-normality hypothesis has been checked for the distributions of all the 148 countries through different tests, Kolmogorov-Smirnov and Cramér-Von Mises, confirming that it cannot be rejected only for the countries of intermediate economy.

  1. Selective logging in the Brazilian Amazon.

    Science.gov (United States)

    G. P. Asner; D. E. Knapp; E. N. Broadbent; P. J. C. Oliveira; M Keller; J. N. Silva

    2005-01-01

    Amazon deforestation has been measured by remote sensing for three decades. In comparison, selective logging has been mostly invisible to satellites. We developed a large-scale, high-resolution, automated remote-sensing analysis of selective logging in the top five timber-producing states of the Brazilian Amazon. Logged areas ranged from 12,075 to 19,823 square...

  2. Identification and Management of Pump Thrombus in the HeartWare Left Ventricular Assist Device System: A Novel Approach Using Log File Analysis.

    Science.gov (United States)

    Jorde, Ulrich P; Aaronson, Keith D; Najjar, Samer S; Pagani, Francis D; Hayward, Christopher; Zimpfer, Daniel; Schlöglhofer, Thomas; Pham, Duc T; Goldstein, Daniel J; Leadley, Katrin; Chow, Ming-Jay; Brown, Michael C; Uriel, Nir

    2015-11-01

    The study sought to characterize patterns in the HeartWare (HeartWare Inc., Framingham, Massachusetts) ventricular assist device (HVAD) log files associated with successful medical treatment of device thrombosis. Device thrombosis is a serious adverse event for mechanical circulatory support devices and is often preceded by increased power consumption. Log files of the pump power are easily accessible on the bedside monitor of HVAD patients and may allow early diagnosis of device thrombosis. Furthermore, analysis of the log files may be able to predict the success rate of thrombolysis or the need for pump exchange. The log files of 15 ADVANCE trial patients (algorithm derivation cohort) with 16 pump thrombus events treated with tissue plasminogen activator (tPA) were assessed for changes in the absolute and rate of increase in power consumption. Successful thrombolysis was defined as a clinical resolution of pump thrombus including normalization of power consumption and improvement in biochemical markers of hemolysis. Significant differences in log file patterns between successful and unsuccessful thrombolysis treatments were verified in 43 patients with 53 pump thrombus events implanted outside of clinical trials (validation cohort). The overall success rate of tPA therapy was 57%. Successful treatments had significantly lower measures of percent of expected power (130.9% vs. 196.1%, p = 0.016) and rate of increase in power (0.61 vs. 2.87, p Log file parameters can potentially predict the likelihood of successful tPA treatments and if validated prospectively, could substantially alter the approach to thrombus management. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  3. Artificial intelligence approach to interwell log correlation

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jong-Se [Korea Maritime University, Pusan(Korea); Kang, Joo Myung [Seoul National University, Seoul(Korea); Kim, Jung Whan [Korea National Oil Corp., Anyang(Korea)

    2000-04-30

    This paper describes a new approach to automated interwell log correlation using artificial intelligence and principal component analysis. The approach to correlate wire line logging data is on the basis of a large set of subjective rules that are intended to represent human logical processes. The data processed are mainly the qualitative information such as the characteristics of the shapes extracted along log traces. The apparent geologic zones are identified by pattern recognition for the specific characteristics of log trace collected as a set of objects by object oriented programming. The correlation of zones between wells is made by rule-based inference program. The reliable correlation can be established from the first principal component logs derived from both the important information around well bore and the largest common part of variances of all available well log data. Correlation with field log data shows that this approach can make interwell log correlation more reliable and accurate. (author). 6 refs., 7 figs.

  4. The Meaning of Logs

    NARCIS (Netherlands)

    Etalle, Sandro; Massacci, Fabio; Yautsiukhin, Artsiom

    2007-01-01

    While logging events is becoming increasingly common in computing, in communication and in collaborative work, log systems need to satisfy increasingly challenging (if not conflicting) requirements.Despite the growing pervasiveness of log systems, to date there is no high-level framework which

  5. The Meaning of Logs

    NARCIS (Netherlands)

    Etalle, Sandro; Massacci, Fabio; Yautsiukhin, Artsiom; Lambrinoudakis, Costas; Pernul, Günther; Tjoa, A Min

    While logging events is becoming increasingly common in computing, in communication and in collaborative environments, log systems need to satisfy increasingly challenging (if not conflicting) requirements. In this paper we propose a high-level framework for modeling log systems, and reasoning about

  6. Use of log-skew-normal distribution in analysis of continuous data with a discrete component at zero

    OpenAIRE

    Chai, High Seng; Bailey, Kent R.

    2008-01-01

    The problem of analyzing a continuous variable with a discrete component is addressed within the frame-work of the mixture model proposed by Moulton and Halsey. The model can be generalized by the introduction of the log-skew-normal distribution for the continuous component, and the fit can be significantly improved by its use, while retaining the interpretation of regression parameter estimates. Simulation studies and application to a real data set are used for demonstration.

  7. MI-GWAS: a SAS platform for the analysis of inherited and maternal genetic effects in genome-wide association studies using log-linear models

    Directory of Open Access Journals (Sweden)

    Mitchell Laura E

    2011-04-01

    Full Text Available Abstract Background Several platforms for the analysis of genome-wide association data are available. However, these platforms focus on the evaluation of the genotype inherited by affected (i.e. case individuals, whereas for some conditions (e.g. birth defects the genotype of the mothers of affected individuals may also contribute to risk. For such conditions, it is critical to evaluate associations with both the maternal and the inherited (i.e. case genotype. When genotype data are available for case-parent triads, a likelihood-based approach using log-linear modeling can be used to assess both the maternal and inherited genotypes. However, available software packages for log-linear analyses are not well suited to the analysis of typical genome-wide association data (e.g. including missing data. Results An integrated platform, Maternal and Inherited Analyses for Genome-wide Association Studies (MI-GWAS for log-linear analyses of maternal and inherited genetic effects in large, genome-wide datasets, is described. MI-GWAS uses SAS and LEM software in combination to appropriately format data, perform the log-linear analyses and summarize the results. This platform was evaluated using existing genome-wide data and was shown to perform accurately and relatively efficiently. Conclusions The MI-GWAS platform provides a valuable tool for the analysis of association of a phenotype or condition with maternal and inherited genotypes using genome-wide data from case-parent triads. The source code for this platform is freely available at http://www.sph.uth.tmc.edu/sbrr/mi-gwas.htm.

  8. Code of practice for the use of sealed radioactive sources in borehole logging (1998)

    International Nuclear Information System (INIS)

    1989-12-01

    The purpose of this code is to establish working practices, procedures and protective measures which will aid in keeping doses, arising from the use of borehole logging equipment containing sealed radioactive sources, to as low as reasonably achievable and to ensure that the dose-equivalent limits specified in the National Health and Medical Research Council s radiation protection standards, are not exceeded. This code applies to all situations and practices where a sealed radioactive source or sources are used through wireline logging for investigating the physical properties of the geological sequence, or any fluids contained in the geological sequence, or the properties of the borehole itself, whether casing, mudcake or borehole fluids. The radiation protection standards specify dose-equivalent limits for two categories: radiation workers and members of the public. 3 refs., tabs., ills

  9. The Auto-Gopher: A Wireline Rotary-Percussive Deep Sampler

    Science.gov (United States)

    Bar-Cohen, Yoseph; Zacny, Kris; Badescu, Mircea; Lee, Hyeong Jae; Sherrit, Stewart; Bao, Xiaoqi; Paulsen, Gale L.; Beegle, Luther

    2016-01-01

    Accessing regions on planetary bodies that potentially preserved biosignatures or are presently habitable is vital to meeting NASA solar system "Search for Life" exploration objectives. To address these objectives, a wireline deep rotary-percussive corer called Auto-Gopher was developed. The percussive action provides effective material fracturing and the rotation provides effective cuttings removal. To increase the drill's penetration rate, the percussive and rotary motions are operated simultaneously. Initially, the corer was designed as a percussive mechanism for sampling ice and was demonstrated in 2005 in Antarctica reaching about 2 m deep. The lessons learned suggested the need to use a combination of rotation and hammering to maximize the penetration rate. This lesson was implemented into the Auto-Gopher-I deep drill which was demonstrated to reach 3-meter deep in gypsum. The average drilling power that was used has been in the range of 100-150 Watt, while the penetration rate was approximately 2.4 m/hr. Recently, a task has started with the goal to develop Auto-Gopher-II that is equipped to execute all the necessary functions in a single drilling unit. These functions also include core breaking, retention and ejection in addition drilling. In this manuscript, the Auto-Gopher-II, its predecessors and their capability are described and discussed.

  10. Auto-Gopher: A Wireline Deep Sampler Driven by Piezoelectric Percussive Actuator and EM Rotary Motor

    Science.gov (United States)

    Badescu, Mircea; Ressa, Aaron; Jae Lee, Hyeong; Bar-Cohen, Yoseph; Sherrit, Stewart; Zacny, Kris; Paulsen, Gale L.; Beegle, Luther; Bao, Xiaoqi

    2013-01-01

    The ability to penetrate subsurfaces and perform sample acquisition at depth of meters may be critical for future NASA in-situ exploration missions to bodies in the solar system, including Mars and Europa. A corer/sampler was developed with the goal of enabling acquisition of samples from depths of several meters where if used on Mars would be beyond the oxidized and sterilized zone. For this purpose, we developed a rotary-hammering coring drill, called Auto-Gopher, which employs a piezoelectric actuated percussive mechanism for breaking formations and an electric motor that rotates the bit to remove the powdered cuttings. This sampler is a wireline mechanism that can be fed into and retrieved from the drilled hole using a winch and a cable. It includes an inchworm anchoring mechanism allowing the drill advancement and weight on bit control without twisting the reeling and power cables. The penetration rate is being optimized by simultaneously activating the percussive and rotary motions of the Auto-Gopher. The percussive mechanism is based on the Ultrasonic/Sonic Drill/Corer (USDC) mechanism that is driven by piezoelectric stack and that was demonstrated to require low axial preload. The design and fabrication of this device were presented in previous publications. This paper presents the results of laboratory and field tests and lessons learned from this development.

  11. Use of log-skew-normal distribution in analysis of continuous data with a discrete component at zero.

    Science.gov (United States)

    Chai, High Seng; Bailey, Kent R

    2008-08-15

    The problem of analyzing a continuous variable with a discrete component is addressed within the framework of the mixture model proposed by Moulton and Halsey (Biometrics 1995; 51:1570-1578). The model can be generalized by the introduction of the log-skew-normal distribution for the continuous component, and the fit can be significantly improved by its use, while retaining the interpretation of regression parameter estimates. Simulation studies and application to a real data set are used for demonstration. 2008 John Wiley & Sons, Ltd

  12. Assessing the quality of proton PBS treatment delivery using machine log files: comprehensive analysis of clinical treatments delivered at PSI Gantry 2

    International Nuclear Information System (INIS)

    Scandurra, D; Albertini, F; Van der Meer, R; Meier, G; Weber, D C; Bolsi, A; Lomax, A

    2016-01-01

    Pencil beam scanning (PBS) proton therapy requires the delivery of many thousand proton beams, each modulated for position, energy and monitor units, to provide a highly conformal patient treatment. The quality of the treatment is dependent on the delivery accuracy of each beam and at each fraction. In this work we describe the use of treatment log files, which are a record of the machine parameters for a given field delivery on a given fraction, to investigate the integrity of treatment delivery compared to the nominal planned dose. The dosimetry-relevant log file parameters are used to reconstruct the 3D dose distribution on the patient anatomy, using a TPS-independent dose calculation system. The analysis was performed for patients treated at Paul Scherrer Institute on Gantry 2, both for individual fields and per series (or plan), and delivery quality was assessed by determining the percentage of voxels in the log file dose distribution within  +/−  1% of the nominal dose. It was seen that, for all series delivered, the mean pass rate is 96.4%. Furthermore, this work establishes a correlation between the delivery quality of a field and the beam position accuracy. This correlation is evident for all delivered fields regardless of individual patient or plan characteristics. We have also detailed further usefulness of log file analysis within our clinical workflow. In summary, we have highlighted that the integrity of PBS treatment delivery is dependent on daily machine performance and is specifically highly correlated with the accuracy of beam position. We believe this information will be useful for driving machine performance improvements in the PBS field. (paper)

  13. Nova Event Logging System

    International Nuclear Information System (INIS)

    Calliger, R.J.; Suski, G.J.

    1981-01-01

    Nova is a 200 terawatt, 10-beam High Energy Glass Laser currently under construction at LLNL. This facility, designed to demonstrate the feasibility of laser driven inertial confinement fusion, contains over 5000 elements requiring coordinated control, data acquisition, and analysis functions. The large amounts of data that will be generated must be maintained over the life of the facility. Often the most useful but inaccessible data is that related to time dependent events associated with, for example, operator actions or experiment activity. We have developed an Event Logging System to synchronously record, maintain, and analyze, in part, this data. We see the system as being particularly useful to the physics and engineering staffs of medium and large facilities in that it is entirely separate from experimental apparatus and control devices. The design criteria, implementation, use, and benefits of such a system will be discussed

  14. Querying Workflow Logs

    Directory of Open Access Journals (Sweden)

    Yan Tang

    2018-01-01

    Full Text Available A business process or workflow is an assembly of tasks that accomplishes a business goal. Business process management is the study of the design, configuration/implementation, enactment and monitoring, analysis, and re-design of workflows. The traditional methodology for the re-design and improvement of workflows relies on the well-known sequence of extract, transform, and load (ETL, data/process warehousing, and online analytical processing (OLAP tools. In this paper, we study the ad hoc queryiny of process enactments for (data-centric business processes, bypassing the traditional methodology for more flexibility in querying. We develop an algebraic query language based on “incident patterns” with four operators inspired from Business Process Model and Notation (BPMN representation, allowing the user to formulate ad hoc queries directly over workflow logs. A formal semantics of this query language, a preliminary query evaluation algorithm, and a group of elementary properties of the operators are provided.

  15. Decomposition of log crepant birational morphisms between log terminal surfaces

    OpenAIRE

    Fukuda, Shigetaka

    1999-01-01

    We prove that every log crepant birational morphism between log terminal surfaces is decomposed into log-flopping type divisorial contraction morphisms and log blow-downs. Repeating these two kinds of contractions we reach a minimal log minimal surface from any log minimal surface.

  16. The impact of log odds of positive lymph nodes (LODDS) in colon and rectal cancer patient stratification: a single-center analysis of 323 patients.

    Science.gov (United States)

    Scarinci, Andrea; Di Cesare, Tatiana; Cavaniglia, Daniele; Neri, Tiziano; Colletti, Michelle; Cosenza, Giulia; Liverani, Andrea

    2018-03-01

    Log odds of positive nodes (LODDS), defined as the log of the ratio between the number of positive nodes and the number of negative nodes, has been recently introduced as a tool in predicting prognosis. This study aims to establish the effective and prognostic value of LODDS in predicting the survival outcome of CRC patients undergoing surgical resection. The study population is represented by 323 consecutive patients with primary colon or rectal adenocarcinoma thatunderwent curative resection. LODDS values were calculated by empirical logistic formula, log(pnod + 0.5)/(tnod - pnod + 0.5). It was defined as the log of the ratio between the number of positive nodes and the number of negative nodes. The patients were divided into three groups: LODDS0 (≤ - 1.36), LODDS1 (> - 1.36 ≤ - 0.53) and LODDS2 (> - 0.53). Kaplan-Meier curve analyses showed 3-year OS rates of the patients staged by LODDS classification. These values were 88.3, 74.8 and 61.8% for LODDS0, LODDS1 and LODDS2, respectively (P ≤ 0.001). In a multivariate analysis, LODDS is an independent prognostic factor of 3-year OS. This is in contrast to pN stage and lymph node ratio, which shows no statistical significance. ROC analyses showed that LODDS predicted OS better than lymph node ratio. LODDS classification has a better prognostic effect than pN stage and lymph node ratio. LODDS offers a finer stratification and accurately predicts survival of CRC patients.

  17. 0 + 5 Vascular Surgery Residents' Operative Experience in General Surgery: An Analysis of Operative Logs from 12 Integrated Programs.

    Science.gov (United States)

    Smith, Brigitte K; Kang, P Chulhi; McAninch, Chris; Leverson, Glen; Sullivan, Sarah; Mitchell, Erica L

    2016-01-01

    Integrated (0 + 5) vascular surgery (VS) residency programs must include 24 months of training in core general surgery. The Accreditation Council for Graduate Medical Education currently does not require specific case numbers in general surgery for 0 + 5 trainees; however, program directors have structured this time to optimize operative experience. The aim of this study is to determine the case volume and type of cases that VS residents are exposed to during their core surgery training. Accreditation council for graduate medical education operative logs for current 0 + 5 VS residents were obtained and retrospectively reviewed to determine general surgery case volume and distribution between open and laparoscopic cases performed. Standard statistical methods were applied. A total of 12 integrated VS residency programs provided operative case logs for current residents. A total of 41 integrated VS residents in clinical years 2 through 5. During the postgraduate year-1 training year, residents participated in significantly more open than laparoscopic general surgery cases (p surgery cases are hernia repair (20%), skin and soft tissue (7.4%), and breast (6.3%). Residents in programs with core surgery over 3 years participated in significantly more general surgery operations compared with residents in programs with core surgery spread out over 4 years (p = 0.035). 0 + 5 VS residents perform significantly more open operations than laparoscopic operations during their core surgery training. The majority of these operations are minor, nonabdominal procedures. The 0 + 5 VS residency program general surgery operative training requirements should be reevaluated and case minimums defined. The general surgery training component of 0 + 5 VS residencies may need to be restructured to meet the needs of current and future trainees. Copyright © 2016 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  18. Power to the logs!

    CERN Multimedia

    CERN. Geneva; MACMAHON, Joseph

    2015-01-01

    Are you tired of using grep, vi and emacs to read your logs? Do you feel like you’re missing the big picture? Does the word "statistics" put a smile on your face? Then it’s time to give power to the logs!

  19. Digital mineral logging system

    International Nuclear Information System (INIS)

    West, J.B.

    1980-01-01

    A digital mineral logging system acquires data from a mineral logging tool passing through a borehole and transmits the data uphole to an electronic digital signal processor. A predetermined combination of sensors, including a deviometer, is located in a logging tool for the acquisition of the desired data as the logging tool is raised from the borehole. Sensor data in analog format is converted in the logging tool to a digital format and periodically batch transmitted to the surface at a predetermined sampling rate. An identification code is provided for each mineral logging tool, and the code is transmitted to the surface along with the sensor data. The self-identifying tool code is transmitted to the digital signal processor to identify the code against a stored list of the range of numbers assigned to that type of tool. The data is transmitted up the d-c power lines of the tool by a frequency shift key transmission technique. At the surface, a frequency shift key demodulation unit transmits the decoupled data to an asynchronous receiver interfaced to the electronic digital signal processor. During a recording phase, the signals from the logging tool are read by the electronic digital signal processor and stored for later processing. During a calculating phase, the stored data is processed by the digital signal processor and the results are outputted to a printer or plotter, or both

  20. Well log and seismic data analysis for complex pore-structure carbonate reservoir using 3D rock physics templates

    Science.gov (United States)

    Li, Hongbing; Zhang, Jiajia

    2018-04-01

    The pore structure in heterogeneous carbonate rock is usually very complex. This complex pore system makes the relationship between the velocity and porosity of the rock highly scattered, so that for the classical two-dimensional rock physics template (2D RPT) it is not enough to accurately describe the quantitative relationship between the rock elastic parameters of this kind of reservoir and its porosity and water saturation. Therefore it is possible to attribute the effect of pore type to that of the porosity or water saturation, and leads to great deviations when applying such a 2D RPT to predict the porosity and water saturation in seismic reservoir prediction and hydrocarbon detection. This paper first presents a method to establish a new three-dimensional rock physics template (3D RPT) by integrating the Gassmann equations and the porous rock physics model, and use it to characterize the quantitative relation between rock elastic properties and the reservoir parameters including the pore aspect ratio, porosity and water saturation, and to predict these parameters from the known elastic properties. The test results on the real logging and seismic inversion data show that the 3D RPT can accurately describe the variations of elastic properties with the porosity, water saturation and pore-structure parameters, and effectively improve the accuracy of reservoir parameters prediction.

  1. Causal analysis of self-sustaining processes in the log-layer of wall-bounded turbulence

    Science.gov (United States)

    Lozano-Duran, Adrian; Bae, Hyunji Jane

    2017-11-01

    Despite the large amount of information provided by direct numerical simulations of turbulent flows, the underlying dynamics remain elusive even in the most simple and canonical configurations. Most standard methods used to investigate turbulence do not provide a clear causal inference between events, which is necessary to determine this dynamics, particularly in self-sustaning processes. In the present work, we examine the causal interactions between streaks and rolls in the logarithmic layer of minimal turbulent channel flow. Causality between structures is assessed in a non-intrusive manner by transfer entropy, i.e., how much the uncertainty of one structure is reduced by knowing the past states of the others. Streaks are represented by the first Fourier modes of the streamwise velocity, while rolls are defined by the wall-normal and spanwise velocities. The results show that the process is mainly unidirectional rather than cyclic, and that the log-layer motions are sustained by extracting energy from the mean shear, which controls the dynamics and time-scales. The well-known lift-up effect is shown to be not a key ingredient in the causal network between shear, streaks and rolls. Funded by ERC Coturb Madrid Summer Program.

  2. Mariners Weather Log

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Mariners Weather Log (MWL) is a publication containing articles, news and information about marine weather events and phenomena, worldwide environmental impact...

  3. A Novel Approach for Analysis of the Log-Linear Age-Period-Cohort Model: Application to Lung Cancer Incidence

    Directory of Open Access Journals (Sweden)

    Tengiz Mdzinarishvili

    2009-12-01

    Full Text Available A simple, computationally efficient procedure for analyses of the time period and birth cohort effects on the distribution of the age-specific incidence rates of cancers is proposed. Assuming that cohort effects for neighboring cohorts are almost equal and using the Log-Linear Age-Period-Cohort Model, this procedure allows one to evaluate temporal trends and birth cohort variations of any type of cancer without prior knowledge of the hazard function. This procedure was used to estimate the influence of time period and birth cohort effects on the distribution of the age-specific incidence rates of first primary, microscopically confirmed lung cancer (LC cases from the SEER9 database. It was shown that since 1975, the time period effect coefficients for men increase up to 1980 and then decrease until 2004. For women, these coefficients increase from 1975 up to 1990 and then remain nearly constant. The LC birth cohort effect coefficients for men and women increase from the cohort of 1890–94 until the cohort of 1925–29, then decrease until the cohort of 1950–54 and then remain almost unchanged. Overall, LC incidence rates, adjusted by period and cohort effects, increase up to the age of about 72–75, turn over, and then fall after the age of 75–78. The peak of the adjusted rates in men is around the age of 77–78, while in women, it is around the age of 72–73. Therefore, these results suggest that the age distribution of the incidence rates in men and women fall at old ages.

  4. Application of direct-fitting, mass-integral, and multi-ratemethods to analysis of flowing fluid electric conductivity logs fromHoronobe, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Doughty, C.; Tsang, C.-F.; Hatanaka, K.; Yabuuchi, S.; Kurikami, H.

    2007-08-01

    The flowing fluid electric conductivity (FFEC) loggingmethod is an efficient way to provide information on the depths,salinities, and transmissivities of individual conductive featuresintercepted by a borehole, without the use of specialized probes. Usingit in a multiple-flow-rate mode allows, in addition, an estimate of theinherent "far-field" pressure heads in each of the conductive features.The multi-rate method was successfully applied to a 500-m borehole in agranitic formation and reported recently. The present paper presents theapplication of the method to two zones within a 1000-m borehole insedimentary rock, which produced, for each zone, three sets of logs atdifferent pumping rates, each set measured over a period of about oneday. The data sets involve a number of complications, such as variablewell diameter, free water table decline in the well, and effects ofdrilling mud. To analyze data from this borehole, we apply varioustechniques that have been developed for analyzing FFEC logs:direct-fitting, mass-integral, and the multi-rate method mentioned above.In spite of complications associated with the tests, analysis of the datais able to identify 44 hydraulically conducting fractures distributedover the depth interval 150-775 meters below ground surface. Thesalinities (in FEC), and transmissivities and pressure heads (indimensionless form) of these 44 features are obtained and found to varysignificantly among one another. These results are compared with datafrom eight packer tests with packer intervals of 10-80 m, which wereconducted in this borehole over the same depth interval. They are foundto be consistent with these independent packer-test data, thusdemonstrating the robustness of the FFEC logging method under non-idealconditions.

  5. EE-3A Logging Report

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, David W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    1993-12-15

    Two logs of EE-3A were performed during the last couple of weeks. The first of which, was a Temperature/Casing-Collar Locator (CCL) log, which took place on Friday, December 10th., 1993. The second log was a Caliper log which was done in cooperation with the Dia-Log Company, of Odessa, TX. on Monday, December, 13th., 1993.

  6. Racial/Ethnic Differences in Sexual Network Mixing: A Log-Linear Analysis of HIV Status by Partnership and Sexual Behavior Among Most at-Risk MSM.

    Science.gov (United States)

    Fujimoto, Kayo; Williams, Mark L

    2015-06-01

    Mixing patterns within sexual networks have been shown to have an effect on HIV transmission, both within and across groups. This study examined sexual mixing patterns involving HIV-unknown status and risky sexual behavior conditioned on assortative/dissortative mixing by race/ethnicity. The sample used for this study consisted of drug-using male sex workers and their male sex partners. A log-linear analysis of 257 most at-risk MSM and 3,072 sex partners was conducted. The analysis found two significant patterns. HIV-positive most at-risk Black MSM had a strong tendency to have HIV-unknown Black partners (relative risk, RR = 2.91, p sexual behavior (RR = 2.22, p sexual behavior with Whites (RR = 1.72, p sexual network mixing patterns by HIV status.

  7. Sequence Stratigraphy of lower zones of Asmari Formation in Marun Oilfield by using of microfacies analysis, isolith maps and γ- Ray log

    Directory of Open Access Journals (Sweden)

    Jalil Jafari

    2015-01-01

    Full Text Available The Oligo- Miocene Asmari Formation is one of the most important reservoir units of the Marun Oilfield in Dezful Embayment SW Iran, deposited in Zagros foreland basin. The goal of this study is to interpret depositional environment and sequence stratigraphy of lower zones of the Asmari Formation in Well No.281, 342 and 312in Marun Oilfield based on changes in the shape of γ- Ray, isolith maps and microfacies properties. Accordingly, identification of 9 carbonate microfacies and 2 siliciclastic petrofacies were identified that are deposited in four depositional environment including open marine, barrier, lagoon and tidal flat in a homoclinal ramp (consisting of outer, middle and inner ramp. Also, based on the shape of γ- Ray log, There sediment were deposited in marine environment. In open marine and barrier environments, The shape of γ- Ray log is serrated bell-shaped, serrated funnel-shaped, left bow-shaped, serrated shape and right boxcar shape, Whole in the beach environment it is cylinder and funnel shape and in lagoon and tidal flat environment can be seen on right bow to cylinder-shaped. Based on the isolith maps, sandstone of lower zones of the Asmari Formation in Marun Oilfield expanded by deltaic system along the southwestern margin of the basin and influenced by changes in sea level constantly. Sequence stratigraphic analysis led to identification of three third- order (DS1, DS2 and DS3 depositional sequences.

  8. A CDC 1700 on-line system for the analysis, data logging and monitoring of big bubble chamber pictures

    International Nuclear Information System (INIS)

    Guyonnet, J.-L.

    1975-01-01

    This work presents the analysis system of large bubble chamber such as Gargamelle, BEBC pictures realized in the heavy liquid bubble chamber group with scanning and measurement stations on-line with a CDC 1700 computer. This work deals with the general characteristics of these stations and of the computer, and puts emphasis on the conception and functions of the analysis programmes: scanning, measurement and data processing. The data acquisition system runs in a context of real time multiprogrammation [fr

  9. Log4J

    CERN Document Server

    Perry, Steven

    2009-01-01

    Log4j has been around for a while now, and it seems like so many applications use it. I've used it in my applications for years now, and I'll bet you have too. But every time I need to do something with log4j I've never done before I find myself searching for examples of how to do whatever that is, and I don't usually have much luck. I believe the reason for this is that there is a not a great deal of useful information about log4j, either in print or on the Internet. The information is too simple to be of real-world use, too complicated to be distilled quickly (which is what most developers

  10. Quality assurance of geometric accuracy based on an electronic portal imaging device and log data analysis for Dynamic WaveArc irradiation.

    Science.gov (United States)

    Hirashima, Hideaki; Miyabe, Yuki; Nakamura, Mitsuhiro; Mukumoto, Nobutaka; Mizowaki, Takashi; Hiraoka, Masahiro

    2018-04-06

    The purpose of this study was to develop a simple verification method for the routine quality assurance (QA) of Dynamic WaveArc (DWA) irradiation using electronic portal imaging device (EPID) images and log data analysis. First, an automatic calibration method utilizing the outermost multileaf collimator (MLC) slits was developed to correct the misalignment between the center of the EPID and the beam axis. Moreover, to verify the detection accuracy of the MLC position according to the EPID images, various positions of the MLC with intentional errors in the range 0.1-1 mm were assessed. Second, to validate the geometric accuracy during DWA irradiation, tests were designed in consideration of three indices. Test 1 evaluated the accuracy of the MLC position. Test 2 assessed dose output consistency with variable dose rate (160-400 MU/min), gantry speed (2.2-6°/s), and ring speed (0.5-2.7°/s). Test 3 validated dose output consistency with variable values of the above parameters plus MLC speed (1.6-4.2 cm/s). All tests were delivered to the EPID and compared with those obtained using a stationary radiation beam with a 0° gantry angle. Irradiation log data were recorded simultaneously. The 0.1-mm intentional error on the MLC position could be detected by the EPID, which is smaller than the EPID pixel size. In Test 1, the MLC slit widths agreed within 0.20 mm of their exposed values. The averaged root-mean-square error (RMSE) of the dose outputs was less than 0.8% in Test 2 and Test 3. Using log data analysis in Test 3, the RMSE between the planned and recorded data was 0.1 mm, 0.12°, and 0.07° for the MLC position, gantry angle, and ring angle, respectively. The proposed method is useful for routine QA of the accuracy of DWA. © 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

  11. Nuclear well logging in hydrology

    International Nuclear Information System (INIS)

    1971-01-01

    hydrologists trained in the techniques of borehole logging and log analysis. In their report to the IHD Coordinating Council, the fourth session of the Working Group proposed that a technical document be prepared to summarize the status of nuclear logging in hydrology. This report is intended to fulfil that proposal and to meet the need, insofar as is possible at present (1970), for coordinated information on the subject

  12. Modes of log gravity

    NARCIS (Netherlands)

    Bergshoeff, Eric A.; Hohm, Olaf; Rosseel, Jan; Townsend, Paul K.

    2011-01-01

    The physical modes of a recently proposed D-dimensional "critical gravity'', linearized about its anti-de Sitter vacuum, are investigated. All "log mode'' solutions, which we categorize as "spin-2'' or "Proca'', arise as limits of the massive spin-2 modes of the noncritical theory. The linearized

  13. Borehole logging system

    International Nuclear Information System (INIS)

    Allen, L.S.

    1988-01-01

    A radioactive borehole logging tool employs an epithermal neutron detector having a neutron counter surrounded by an inner thermal neutron filter and an outer thermal neutron filter. Located between the inner and outer filters is a neutron moderating material for extending the lifetime of epithermal neutrons to enhance the counting rate of such epithermal neutrons by the neutron counter

  14. Log of Apollo 11.

    Science.gov (United States)

    National Aeronautics and Space Administration, Washington, DC.

    The major events of the first manned moon landing mission, Apollo 11, are presented in chronological order from launch time until arrival of the astronauts aboard the U.S.S. Hornet. The log is descriptive, non-technical, and includes numerous color photographs of the astronauts on the moon. (PR)

  15. Data Mining of Network Logs

    Science.gov (United States)

    Collazo, Carlimar

    2011-01-01

    The statement of purpose is to analyze network monitoring logs to support the computer incident response team. Specifically, gain a clear understanding of the Uniform Resource Locator (URL) and its structure, and provide a way to breakdown a URL based on protocol, host name domain name, path, and other attributes. Finally, provide a method to perform data reduction by identifying the different types of advertisements shown on a webpage for incident data analysis. The procedures used for analysis and data reduction will be a computer program which would analyze the URL and identify and advertisement links from the actual content links.

  16. Inverse Porosity-Hydraulic Conductivity Relationship in Sand-and-Gravel Aquifers Determined From Analysis of Geophysical Well Logs: Implications for Transport Processes

    Science.gov (United States)

    Morin, R. H.

    2004-05-01

    It is intuitive to think of hydraulic conductivity K as varying directly and monotonically with porosity P in porous media. However, laboratory studies and field observations have documented a possible inverse relationship between these two parameters in unconsolidated deposits under certain grain-size distributions and packing arrangements. This was confirmed at two sites in sand-and-gravel aquifers on Cape Cod, Massachusetts, where sets of geophysical well logs were used to examine the interdependence of several aquifer properties. Along with K and P, the resistivity R and the natural-gamma activity G of the surrounding sediments were measured as a function of depth. Qualitative examination of field results from the first site was useful in locating a contaminant plume and inferred an inverse relation between K and P; this was substantiated by a rigorous multivariate analysis of log data collected from the second site where K and P were determined to respond in a bipolar manner among the four independent variables. Along with this result come some implications regarding our conceptual understanding of contaminant transport processes in the shallow subsurface. According to Darcy's law, the interstitial fluid velocity V is proportional to the ratio K/P and, consequently, a general inverse K-P relationship implies that values of V can extend over a much wider range than conventionally assumed. This situation introduces a pronounced flow stratification within these granular deposits that can result in large values of longitudinal dispersivity; faster velocities occur in already fast zones and slower velocities in already slow zones. An inverse K-P relationship presents a new perspective on the physical processes associated with groundwater flow and transport. Although the results of this study apply strictly to the Cape Cod aquifers, they may merit a re-evaluation of modeling approaches undertaken at other locations having similar geologic environments.

  17. Converged Wireless and Wireline Access System Based on Optical Phase Modulation for Both Radio-Over-Fiber and Baseband Signals

    DEFF Research Database (Denmark)

    Yu, Xianbin; Jensen, Jesper Bevensee; Zibar, Darko

    2008-01-01

    -to-zero differential quaternary phase-shift keyed signal and a 5.25-GHz RoF carrying 1.25 Gb/s, enables the use of identical optical receiver structures. The experimental results show that both receivers achieve error-free operation after 80-km standard single-mode fiber transmission. The proposed scheme has potential......We propose and experimentally investigate a scheme for transmitting a phase-modulated radio-over-fiber (RoF) signal along an existing fiber infrastructure without degradation of the existing baseband signal. Optical phase encoding of both signals, namely a baseband 21.4-Gb/s nonreturn...... applications for converged wireless and wireline optical access networks....

  18. Radiology resident MR and CT image analysis skill assessment using an interactive volumetric simulation tool - the RadioLOG project.

    Science.gov (United States)

    Gondim Teixeira, Pedro Augusto; Cendre, Romain; Hossu, Gabriela; Leplat, Christophe; Felblinger, Jacques; Blum, Alain; Braun, Marc

    2017-02-01

    Assess the use of a volumetric simulation tool for the evaluation of radiology resident MR and CT interpretation skills. Forty-three participants were evaluated with a software allowing the visualisation of multiple volumetric image series. There were 7 medical students, 28 residents and 8 senior radiologists among the participants. Residents were divided into two sub-groups (novice and advanced). The test was composed of 15 exercises on general radiology and lasted 45 min. Participants answered a questionnaire on their experience with the test using a 5-point Likert scale. This study was approved by the dean of the medical school and did not require ethics committee approval. The reliability of the test was good with a Cronbach alpha value of 0.9. Test scores were significantly different in all sub-groups studies (p radiological practice (3.9 ± 0.9 on a 5-point scale) and was better than the conventional evaluation methods (4.6 ± 0.5 on a 5-point scale). This software provides a high quality evaluation tool for the assessment of the interpretation skills in radiology residents. • This tool allows volumetric image analysis of MR and CT studies. • A high reliability test could be created with this tool. • Test scores were strongly associated with the examinee expertise level. • Examinees positively evaluated the authenticity and usability of this tool.

  19. Financial feasibility of a log sort yard handling small-diameter logs: A preliminary study

    Science.gov (United States)

    Han-Sup Han; E. M. (Ted) Bilek; John (Rusty) Dramm; Dan Loeffler; Dave Calkin

    2011-01-01

    The value and use of the trees removed in fuel reduction thinning and restoration treatments could be enhanced if the wood were effectively evaluated and sorted for quality and highest value before delivery to the next manufacturing destination. This article summarizes a preliminary financial feasibility analysis of a log sort yard that would serve as a log market to...

  20. Log-Concavity and Strong Log-Concavity: a review.

    Science.gov (United States)

    Saumard, Adrien; Wellner, Jon A

    We review and formulate results concerning log-concavity and strong-log-concavity in both discrete and continuous settings. We show how preservation of log-concavity and strongly log-concavity on ℝ under convolution follows from a fundamental monotonicity result of Efron (1969). We provide a new proof of Efron's theorem using the recent asymmetric Brascamp-Lieb inequality due to Otto and Menz (2013). Along the way we review connections between log-concavity and other areas of mathematics and statistics, including concentration of measure, log-Sobolev inequalities, convex geometry, MCMC algorithms, Laplace approximations, and machine learning.

  1. Geophysical borehole logging

    International Nuclear Information System (INIS)

    McCann, D.; Barton, K.J.; Hearn, K.

    1981-08-01

    Most of the available literature on geophysical borehole logging refers to studies carried out in sedimentary rocks. It is only in recent years that any great interest has been shown in geophysical logging in boreholes in metamorphic and igneous rocks following the development of research programmes associated with geothermal energy and nuclear waste disposal. This report is concerned with the programme of geophysical logging carried out on the three deep boreholes at Altnabreac, Caithness, to examine the effectiveness of these methods in crystalline rock. Of particular importance is the assessment of the performance of the various geophysical sondes run in the boreholes in relation to the rock mass properties. The geophysical data can be used to provide additional in-situ information on the geological, hydrogeological and engineering properties of the rock mass. Fracturing and weathering in the rock mass have a considerable effect on both the design parameters for an engineering structure and the flow of water through the rock mass; hence, the relation between the geophysical properties and the degree of fracturing and weathering is examined in some detail. (author)

  2. A history of nuclear well logging in the oil industry

    International Nuclear Information System (INIS)

    Tittle, C.W.

    1989-01-01

    Spurred by an interest in logging through steel casing γ-ray logging began in the late 1930s followed soon by neutron logging for porosity. These were the first two nuclear well logs. Gamma-gamma density logging was developed during the 1950s. Pulsed neutron lifetime logging appeared in the 1960s; the slim tools came in the early 1970s. Developments since then have included dual detector devices of several types which offered improved measurements or interpretation, γ-ray spectrometry logging (natural and neutron-induced) which identifies certain chemical elements, induced radioactivity logging, and the photoelectric absorption log, which, combined with the density log in a single tool, is known as litho-density logging. A combination of several γ-ray spectrometers in one tool, designed to determine 10 formation elements, was recently introduced, and a new neutron porosity tool measuring epithermal neutron die-away time has been developed. Digital transmission of logging data was a step forward in about 1975. Also, log interpretation techniques have greatly expanded since the advent of digital computers, and the microcomputer has had a distinct impact. It is now practical and economical to do iterative analysis on a suite of logs to obtain an optimum overall interpretation. (author)

  3. Interactive machine learning for postprocessing CT images of hardwood logs

    Science.gov (United States)

    Erol Sarigul; A. Lynn Abbott; Daniel L. Schmoldt

    2003-01-01

    This paper concerns the nondestructive evaluation of hardwood logs through the analysis of computed tomography (CT) images. Several studies have shown that the commercial value of resulting boards can be increased substantially if log sawing strategies are chosen using prior knowledge of internal log defects. Although CT imaging offers a potential means of obtaining...

  4. Multivariate and spatial statistical analysis of Callovo-Oxfordian physical properties from lab and borehole logs data: towards a characterization of lateral and vertical spatial trends in the Meuse/Haute-Marne transposition zone

    International Nuclear Information System (INIS)

    Garcia, M.H.; Rabaute, A.; Yven, B.; Guillemot, D.

    2010-01-01

    Document available in extended abstract form only. The geological exploration of the Meuse/Haute-Marne area began in 1994. Several boreholes were drilled, and the Callovo-Oxfordian argillite, thought to become a potential storage formation, were cored and logged. 2D and 3D seismic surveys were completed, as well as geological field observations, and an underground research laboratory was created. A 250 km 2 -wide Transposition Zone was delimited, which was subject to further investigations in 2007 and 2008, including another series of coring and logging in four additional boreholes, and a tighter 2D seismic survey. The main objective of this study was to improve the knowledge of the spatial variability of geological and physical properties of the Callovo-Oxfordian formation. The paper focuses on the three following aspects of the study to present and discuss the methods that have been used and the results that have been obtained: - Use of well-log data to identify equivalent homogeneous log-units on the boreholes. - Relating log attributes to physical properties of argillites measured on cores in laboratory. - Study of lateral and vertical spatial trends of selected physical properties across the Transposition Zone (TZ). To identify equivalent homogeneous log-units, a combination of Principal Component Analysis (PCA) and Fuzzy Cluster Analysis (FCA) was used. PCA was classically performed to reduce the number of variables to retain principal components gathering most of the original dataset variance. PCA was also used to identify isolated groups of correlated variables that could be associated to different properties of the formation. Then, FCA was applied to identify homogeneous log-units on the eight boreholes across the TZ. Well-logs data being much more numerous and better distributed along boreholes than lab data measured on rock samples, relations and correlations were sought between the two types of data to identify log attributes that were likely to provide

  5. Integrated seismic analysis of the Chalk Group in eastern Denmark—Implications for estimates of maximum palaeo-burial in southwest Scandinavia

    DEFF Research Database (Denmark)

    Nielsen, Lars; Boldreel, Lars Ole; Hansen, Thomas Mejer

    2011-01-01

    of the Chalk Group below the Stevns peninsula, eastern part of the Danish Basin. The model contains four layers in the ~860m thick Chalk Group with mean velocities of 2.2km/s, 2.4km/s, 3.1km/s, and 3.9–4.3km/s. Sonic and gamma wireline log data from two cored boreholes represent the upper ~450m of the Chalk...... anomaly will be over-estimated by ~150–200m if the analysis is based on the average Chalk Group velocity and clay content is disregarded. Burial anomaly values of ~450–600m result if the strongest velocity contrast at ~600–650m depth is interpreted to be a result of diagenetic effects, consistent...

  6. Logging in the campus: borehole research and monitoring in a test hole in Barcelona (Spain)

    Science.gov (United States)

    Jurado, M. J.; Crespo, J.; Espallargas, R.

    2012-04-01

    Almera-1 hole was drilled for research purposes in the University of Barcelona campus area. The hole is 214m deep and was drilled in Quaternary to Paleozoic rocks in a urban area, next to the Institute of Earth Sciences (CSIC) borehole research lab. The main objectives for drilling a research hole were both the study of the poorly known subsurface geology and structure in this urban area and the construction of a dedicated infrastructure for logging tools tests, calibrations and long term monitoring. A direct connection to the lab was built to facilitate long term measuring experiments tool powering and data monitoring. A second auxiliary hole, Almera-2 50m deep was drilled to carry out cross-hole and tomographic experiments and hydrological monitoring. The upper section of Almera-1 hole is cased with PVC and the lowermost is an open hole section in paleozoic rock. The entire hole was logged in open hole mode (before casing) and also after the hole was cased in order to study the effect of the PVC casing on different logging tools responses (total and spectral gamma radioactivity through casing, acoustic televiewer through casing, full wave sonic through casing and magnetic susceptibility through casing). The comparison shows the effect on each of these tools response of the PVC casing. Also how the tools responses are more or less affected by the attenuation caused by the PVC of the rock signal and how this is more or less critical in the diverse lithologies represented in the Almera-1 hole. Wireline drilling was used to obtain best core recovery and to carry out log-core comparative analyses for logging tool response calibration and log-core correlation. The results obtained in the study of gamma ray (total and spectral), magnetic susceptibility and acoustic petrophysics are shown.

  7. Analysis of Geophysical Logs From Six Boreholes at Lariat Gulch, Former U.S. Air Force Site PJKS, Jefferson County, Colorado

    National Research Council Canada - National Science Library

    Paillet, Frederick L; Hodges, Richard E; Corland, Barbara S

    2002-01-01

    .... Air Force site PJKS in Jefferson County near Denver, Colorado. Geophysical logs include gamma, normal resistivity, fluid-column temperature and resistivity, caliper, televiewer, and heat-pulse flowmeter...

  8. CS2 analysis in presence of non-Gaussian background noise - Effect on traditional estimators and resilience of log-envelope indicators

    Science.gov (United States)

    Borghesani, P.; Antoni, J.

    2017-06-01

    Second-order cyclostationary (CS2) analysis has become popular in the field of machine diagnostics and a series of digital signal processing techniques have been developed to extract CS2 components from the background noise. Among those techniques, squared envelope spectrum (SES) and cyclic modulation spectrum (CMS) have gained popularity thanks to their high computational efficiency and simple implementation. The effectiveness of CMS and SES has been previously quantified based on the hypothesis of Gaussian background noise and has led to statistical tests for the presence of CS2 peaks in squared envelope spectra and cyclic modulation spectra. However a recently established link of CMS with SES and of SES with kurtosis has exposed a potential weakness of those indicators in the case of highly leptokurtic background noise. This case is often present in practice when the machine is subjected to highly impulsive phenomena, either due to harsh operating conditions or to electric noise generated by power electronics and captured by the sensor. This study investigates and quantifies for the first time the effect of leptokurtic noise on the capabilities of SES and CMS, by analysing three progressively harsh situations: high kurtosis, infinite kurtosis and alpha-stable background noise (for which even first and second-order moments are not defined). Then the resilience of a recently proposed family of CS2 indicators, based on the log-envelope, is verified analytically, numerically and experimentally in the case of highly leptokurtic noise.

  9. APPLICATION OF WELL LOG ANALYSIS IN ASSESSMENT OF PETROPHYSICAL PARAMETERS AND RESERVOIR CHARACTERIZATION OF WELLS IN THE “OTH” FIELD, ANAMBRA BASIN, SOUTHERN NIGERIA

    Directory of Open Access Journals (Sweden)

    Eugene URORO

    2014-12-01

    Full Text Available Over the past years, the Anambra basin one of Nigeria’s inland basins has recorded significant level of hydrocarbon exploration activities. The basin has been confirmed by several authors from source rock analyses to have the potential for generating hydrocarbon. For the hydrocarbon to be exploited, it is imperative to have a thorough understanding of the reservoir. Computer-assisted log analyses were employed to effectively evaluate the petrophysical parameters such as the shale volume (Vsh, total porosity (TP, effective porosity (EP, water saturation (Sw, and hydrocarbon saturation (Sh. Cross-plots of the petrophysical parameters versus depth were illustrated. Five hydrocarbon bearing reservoirs were delineated in well 1, four in well 2. The reservoirs in well 3 do not contain hydrocarbon. The estimated reservoir porosity varies from 10% to 21% while their permeability values range from 20md to 1400md. The porosity and permeability values suggest that reservoirs are good enough to store and also permit free flow of fluid. The volume of shale (0.05% to 0.35% analysis reveals that the reservoirs range from shaly sand to slightly shaly sand to clean sand reservoir. On the basis of petrophysics data, the reservoirs are interpreted a good quality reservoir rocks which has been confirmed with high effective porosity range between 20% and high hydrocarbon saturation exceeding 55% water saturation in well 1 and well 2. Water saturation 3 is nearly 100% although the reservoir properties are good.  

  10. Operational Review of the First Wireline In Situ Stress Test in Scientific Ocean Drilling

    Directory of Open Access Journals (Sweden)

    Casey Moore

    2012-04-01

    Full Text Available Scientific ocean drilling’s first in situ stress measurement was made at Site C0009A during Integrated Ocean Drilling Program (IODP Expedition 319 as part of Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE Stage 2. The Modular Formation Dynamics Tester (MDT, Schlumbergerwireline logging tool was deployed in riser Hole C0009A to measure in situ formation pore pressure, formation permeability (often reported as mobility=permeability/viscosity, and the least principal stress (S3 at several isolated depths (Saffer et al., 2009; Expedition 319 Scientists, 2010. The importance of in situ stress measurements is not only for scientific interests in active tectonic drilling, but also for geomechanical and well bore stability analyses. Certain in situ tools were not previously available for scientific ocean drilling due to the borehole diameter and open hole limits of riserless drilling. The riser-capable drillship, D/V Chikyu,now in service for IODP expeditions, allows all of the techniques available to estimate the magnitudes and orientations of 3-D stresses to be used. These techniques include downhole density logging for vertical stress, breakout and caliper log analyses for maximum horizontal stress, core-based anelastic strain recovery (ASR, used in the NanTroSEIZE expeditions in 2007–2008, and leak-off test (Lin et al., 2008 and minifrac/hydraulic fracturing (NanTroSEIZE Expedition319 in 2009. In this report, the whole operational planning process related to in situ measurements is reviewed, and lessons learned from Expedition 319 are summarized for efficient planning and testing in the future.

  11. Smartphone log data in a qualitative perspective

    DEFF Research Database (Denmark)

    Ørmen, Jacob; Thorhauge, Anne Mette

    2015-01-01

    Log data from smartphones have primarily been used in large-scale research designs to draw statistical inferences from hundreds or even thousands of participants. In this article, we argue that more qualitatively oriented designs can also benefit greatly from integrating these rich data sources...... into studies of smartphones in everyday life. Through an illustrative study, we explore a more nuanced perspective on what can be considered “log data” and how these types of data can be collected and analysed. A qualitative approach to log data analysis offers researchers new opportunities to situate...... smartphone use within people’s practices, norms, and routines. This is of relevance both to studies focusing on smartphones as cultural objects in everyday life and studies that use such devices as proxies for social behaviour more generally. We argue that log data, for instance in in-depth interviews, may...

  12. Log(s) physics results from CDF

    International Nuclear Information System (INIS)

    1989-01-01

    The Collider Detector at Fermilab (CDF) is a large, azimuthally symmetric detector designed to study bar pp interactions at the Fermilab Tevatron Collider. Results are presented from data taken with a minimum bias trigger at √s = 630 and 1800 GeV during the 1987 run. The topics include the current analysis of dn/dη and some very preliminary results on short range pseudorapidity correlations and Bose-Einstein correlations. 7 refs., 5 figs., 2 tabs

  13. AML (Advanced Mud Logging: First Among Equals

    Directory of Open Access Journals (Sweden)

    T. Loermans

    2017-09-01

    Full Text Available During the past ten years an enormous development in mud logging technology has been made. Traditional mud logging was only qualitative in nature, and mudlogs could not be used for the petrophysical well evaluations which form the basis for all subsequent activities on wells and fields. AML however can provide quantitative information, logs with a reliability, trueness and precision like LWD and WLL. Hence for well evaluation programmes there are now three different logging methods available, each with its own pros and cons on specific aspects: AML, LWD and WLL. The largest improvements have been made in mud gas analysis and elemental analysis of cuttings. Mud gas analysis can yield hydrocarbon fluid composition for some components with a quality like PVT analysis, hence not only revolutionising the sampling programme so far done with only LWD/WLL, but also making it possible to geosteer on fluid properties. Elemental analysis of cuttings, e.g. with XRF, with an ability well beyond the capabilities of the spectroscopy measurements possible earlier with LWD/WLL tools, is opening up improved ways to evaluate formations, especially of course where the traditional methods are falling short of requirements, such as in unconventional reservoirs. An overview and specific examples of these AML logs is given, from which it may be concluded that AML now ought to be considered as “first among its equals”.

  14. Analysis of Critical Permeabilty, Capillary Pressure and Electrical Properties for Mesaverde Tight Gas Sandstones from Western U.S. Basins

    Energy Technology Data Exchange (ETDEWEB)

    Alan Byrnes; Robert Cluff; John Webb; John Victorine; Ken Stalder; Daniel Osburn; Andrew Knoderer; Owen Metheny; Troy Hommertzheim; Joshua Byrnes; Daniel Krygowski; Stefani Whittaker

    2008-06-30

    Although prediction of future natural gas supply is complicated by uncertainty in such variables as demand, liquefied natural gas supply price and availability, coalbed methane and gas shale development rate, and pipeline availability, all U.S. Energy Information Administration gas supply estimates to date have predicted that Unconventional gas sources will be the dominant source of U.S. natural gas supply for at least the next two decades (Fig. 1.1; the period of estimation). Among the Unconventional gas supply sources, Tight Gas Sandstones (TGS) will represent 50-70% of the Unconventional gas supply in this time period (Fig. 1.2). Rocky Mountain TGS are estimated to be approximately 70% of the total TGS resource base (USEIA, 2005) and the Mesaverde Group (Mesaverde) sandstones represent the principal gas productive sandstone unit in the largest Western U.S. TGS basins including the basins that are the focus of this study (Washakie, Uinta, Piceance, northern Greater Green River, Wind River, Powder River). Industry assessment of the regional gas resource, projection of future gas supply, and exploration programs require an understanding of reservoir properties and accurate tools for formation evaluation. The goal of this study is to provide petrophysical formation evaluation tools related to relative permeability, capillary pressure, electrical properties and algorithms for wireline log analysis. Detailed and accurate moveable gas-in-place resource assessment is most critical in marginal gas plays and there is need for quantitative tools for definition of limits on gas producibility due to technology and rock physics and for defining water saturation. The results of this study address fundamental questions concerning: (1) gas storage; (2) gas flow; (3) capillary pressure; (4) electrical properties; (5) facies and upscaling issues; (6) wireline log interpretation algorithms; and (7) providing a web-accessible database of advanced rock properties. The following text

  15. Log::ProgramInfo: A Perl module to collect and log data for bioinformatics pipelines.

    Science.gov (United States)

    Macdonald, John M; Boutros, Paul C

    2016-01-01

    To reproduce and report a bioinformatics analysis, it is important to be able to determine the environment in which a program was run. It can also be valuable when trying to debug why different executions are giving unexpectedly different results. Log::ProgramInfo is a Perl module that writes a log file at the termination of execution of the enclosing program, to document useful execution characteristics. This log file can be used to re-create the environment in order to reproduce an earlier execution. It can also be used to compare the environments of two executions to determine whether there were any differences that might affect (or explain) their operation. The source is available on CPAN (Macdonald and Boutros, Log-ProgramInfo. http://search.cpan.org/~boutroslb/Log-ProgramInfo/). Using Log::ProgramInfo in programs creating result data for publishable research, and including the Log::ProgramInfo output log as part of the publication of that research is a valuable method to assist others to duplicate the programming environment as a precursor to validating and/or extending that research.

  16. Dynamic Planar Convex Hull with Optimal Query Time and O(log n · log log n ) Update Time

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Jakob, Riko

    2000-01-01

    The dynamic maintenance of the convex hull of a set of points in the plane is one of the most important problems in computational geometry. We present a data structure supporting point insertions in amortized O(log n · log log log n) time, point deletions in amortized O(log n · log log n) time, a...

  17. Genesis Analysis of High-Gamma Ray Sandstone Reservoir and Its Log Evaluation Techniques: A Case Study from the Junggar Basin, Northwest China

    Directory of Open Access Journals (Sweden)

    Liang Wang

    2013-01-01

    Full Text Available In the Junggar basin, northwest China, many high gamma-ray (GR sandstone reservoirs are found and routinely interpreted as mudstone non-reservoirs, with negative implications for the exploration and exploitation of oil and gas. Then, the high GR sandstone reservoirs’ recognition principles, genesis, and log evaluation techniques are systematically studied. Studies show that the sandstone reservoirs with apparent shale content greater than 50% and GR value higher than 110API can be regarded as high GR sandstone reservoir. The high GR sandstone reservoir is mainly and directly caused by abnormally high uranium enrichment, but not the tuff, feldspar or clay mineral. Affected by formation’s high water sensitivity and poor borehole quality, the conventional logs can not recognize reservoir and evaluate the physical property of reservoirs. Then, the nuclear magnetic resonance (NMR logs is proposed and proved to be useful in reservoir recognition and physical property evaluation.

  18. Non-destructive analysis and detection of internal characteristics of spruce logs through X computerized tomography; Detection et analyse non destructive de caracteristiques internes de billons d'epicea commun (PICEA ABIES (L.) KARST) par tomographie a rayons X

    Energy Technology Data Exchange (ETDEWEB)

    Longuetaud, F

    2005-10-15

    Computerized tomography allows a direct access to internal features of scanned logs on the basis of density and moisture content variations. The objective of this work is to assess the feasibility of an automatic detection of internal characteristics with the final aim of conducting scientific analyses. The database is constituted by CT images of 24 spruces obtained with a medical CT scanner. Studied trees are representative of several social status and are coming from four stands located in North-Eastern France, themselves are representative of several age, density and fertility classes. The automatic processing developed are the following. First, pith detection in logs dealing with the problem of knot presence and ring eccentricity. The accuracy of the localisation was less than one mm. Secondly, the detection of the sapwood/heart-wood limit in logs dealing with the problem of knot presence (main source of difficulty). The error on the diameter was 1.8 mm which corresponds to a relative error of 1.3 per cent. Thirdly, the detection of the whorls location and comparison with an optical method. Fourthly the detection of individualized knots. This process allows to count knots and to locate them in a log (longitudinal position and azimuth); however, the validation of the method and extraction of branch diameter and inclination are still to be developed. An application of this work was a variability analysis of the sapwood content in the trunk: at the within-tree level, the sapwood width was found to be constant under the living crown; at the between-tree level, a strong correlation was found with the amount of living branches. A great number of analyses are possible from our work results, among others: architectural analysis with the pith tracking and the apex death occurrence; analysis of radial variations of the heart-wood shape; analysis of the knot distribution in logs. (author)

  19. Minimal Model Theory for Log Surfaces

    OpenAIRE

    Fujino, Osamu

    2012-01-01

    We discuss the log minimal model theory for log surfaces. We show that the log minimal model program, the finite generation of log canonical rings, and the log abundance theorem for log surfaces hold true under assumptions weaker than the usual framework of the log minimal model theory.

  20. Logging Activity in the Trinational Amazonian Region of Pando/Bolivia, Acre and Rond“nia/Brazil, and Madre de Dios/Peru: Analysis of Existing Data

    Science.gov (United States)

    Mendoza, E.; Brilhante, S. H.; Brown, I.; Peralta, R.; Rivero, S.; Melendez, N.

    2002-12-01

    Logging activity in the trinational southwestern Amazonia will grow in importance as a driver of regional land-use change as expanding road access facilitates both timber extraction and transport to international markets. Official data on current activity in this ~50 million ha region are limited and inconsistent with differences as much as twenty-fold between official estimates; nevertheless, they serve as guides for understanding the relative magnitude of logging activities. For 2000, an estimated 5 million m3 of timber were commercialized in Rondonia, 400,000 m3 in Acre, Brazil, and 200,000 m3 for the combined departments of Pando, Bolivia and Madre de Dios, Peru. About 70% of this timber originates from clear cutting done for pasture and agriculture activities, nearly a third from unregulated selective logging, and only 2% from managed selective logging. Eight timber species are preferentially extracted. The total area for timber concessions in Acre, Pando and Madre de Dios extends to about 4 million ha for a potential timber supply of 65 million m3. About 150,000 m3/yr of illegal timber is confiscated by federal and state agencies in Acre, Pando and Madre de Dios. Problems of enforcement in the region are due principally to the lack of trained personnel and little cooperation among agencies of the three countries. Proposed development plans indicate a 3- to >10-fold increase in logging activity in the Acre and Pando regions during the coming decade. More detailed studies are urgently needed to guide sustainable development of this resource in southwestern Amazonia.

  1. Geological & Geophysical findings from seismic, well log and core data for marine gas hydrate deposits at the 1st offshore methane hydrate production test site in the eastern Nankai Trough, offshore Japan: An overview

    Science.gov (United States)

    Fujii, T.; Noguchi, S.; Takayama, T.; Suzuki, K.; Yamamoto, K.

    2012-12-01

    In order to evaluate productivity of gas from marine gas hydrate by the depressurization method, Japan Oil, Gas and Metals National Corporation is planning to conduct a full-scale production test in early 2013 at the AT1 site in the north slope of Daini-Atsumi Knoll in the eastern Nankai Trough, Japan. The test location was determined using the combination of detailed 3D seismic reflection pattern analysis, high-density velocity analysis, and P-impedance inversion analysis, which were calibrated using well log data obtained in 2004. At the AT1 site, one production well (AT1-P) and two monitoring wells (AT1-MC and MT1) were drilled from February to March 2012, followed by 1 coring well (AT1-C) from June to July 2012. An extensive logging program with logging while drilling (LWD) and wireline-logging tools, such as GeoVISION (resistivity image), EcoScope (neutron/density porosity, mineral spectroscopy etc.), SonicScanner (Advanced Sonic tool), CMR/ProVISION (Nuclear Magnetic Resonance Tools), XPT (formation pressure, fluid mobility), and IsolationScanner (ultrasonic cement evaluation tools) was conducted at AT1-MC well to evaluate physical reservoir properties of gas hydrate-bearing sediments, to determine production test interval in 2013, and to evaluate cement bonding. Methane hydrate concentrated zone (MHCZ) confirmed by the well logging at AT1-MC was thin turbidites (tens of centimeters to few meters) with 60 m of gross thickness, which is composed of lobe type sequences in the upper part of it and channel sand sequences in the lower part. The gross thickness of MHCZ in the well is thicker than previous wells in 2004 (A1, 45 m) located around 150 m northeast, indicating that the prediction given by seismic inversion analysis was reasonable. Well-to-well correlation between AT1-MC and MT1 wells within 40 m distance exhibited that lateral continuity of these sand layers (upper part of reservoir) are fairly good, which representing ideal reservoir for the production

  2. Logging Concessions Enable Illegal Logging Crisis in the Peruvian Amazon

    Science.gov (United States)

    Finer, Matt; Jenkins, Clinton N.; Sky, Melissa A. Blue; Pine, Justin

    2014-04-01

    The Peruvian Amazon is an important arena in global efforts to promote sustainable logging in the tropics. Despite recent efforts to achieve sustainability, such as provisions in the US-Peru Trade Promotion Agreement, illegal logging continues to plague the region. We present evidence that Peru's legal logging concession system is enabling the widespread illegal logging via the regulatory documents designed to ensure sustainable logging. Analyzing official government data, we found that 68.3% of all concessions supervised by authorities were suspected of major violations. Of the 609 total concessions, nearly 30% have been cancelled for violations and we expect this percentage to increase as investigations continue. Moreover, the nature of the violations indicate that the permits associated with legal concessions are used to harvest trees in unauthorized areas, thus threatening all forested areas. Many of the violations pertain to the illegal extraction of CITES-listed timber species outside authorized areas. These findings highlight the need for additional reforms.

  3. REAL-TIME TRACER MONITORING OF RESERVOIR STIMULATION PROCEDURES VIA ELECTRONIC WIRELINE AND TELEMETRY DATA TRANSMISSION

    Energy Technology Data Exchange (ETDEWEB)

    George Scott III

    2003-08-01

    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

  4. Extracting useful knowledge from event logs

    DEFF Research Database (Denmark)

    Djenouri, Youcef; Belhadi, Asma; Fournier-Viger, Philippe

    2018-01-01

    Business process analysis is a key activity that aims at increasing the efficiency of business operations. In recent years, several data mining based methods have been designed for discovering interesting patterns in event logs. A popular type of methods consists of applying frequent itemset mini...

  5. Analyzing Log Files using Data-Mining

    Directory of Open Access Journals (Sweden)

    Marius Mihut

    2008-01-01

    Full Text Available Information systems (i.e. servers, applications and communication devices create a large amount of monitoring data that are saved as log files. For analyzing them, a data-mining approach is helpful. This article presents the steps which are necessary for creating an ‘analyzing instrument’, based on an open source software called Waikato Environment for Knowledge Analysis (Weka [1]. For exemplification, a system log file created by a Windows-based operating system, is used as input file.

  6. A comparison of dried shiitake mushroom in log cultivation and mycelial cultivation from different geographical origins using stable carbon and nitrogen isotope analysis

    International Nuclear Information System (INIS)

    Suzuki, Yaeko; Nakashita, Rumiko; Ishikawa, Noemia Kazue; Tabuchi, Akiko; Sakuno, Emi; Tokimoto, Keisuke

    2015-01-01

    We determined carbon and nitrogen isotopic compositions (δ 13 C and δ 15 N) of dried shiitake mushroom (Lentinula edodes) samples from Japan, China, South Korea and Brazil in order to discriminate their geographical origins. In log cultivation, the δ 13 C values of Japanese dried shiitake samples were lower than those of Chinese samples, depending on the δ 13 C values of log and their growth conditions. In mycelial cultivation, the δ 13 C and δ 15 N values of Japanese dried shiitake samples were higher than those of Chinese samples. By using the δ 13 C and δ 15 N values, 87.4% of Japanese dried shiitake samples (n = 95) and 87.9% of Chinese dried shiitake samples (n = 66) in log cultivation, 90.0% of the Japanese dried shiitake samples (n = 50) and 93.9% of Chinese dried shiitake samples (n = 114) in mycelial cultivation, were correctly classified according to the production site. These results suggested that the δ 13 C and δ 15 N values will be potentially useful for tracing their geographical origin of dried shiitake samples. (author)

  7. Working with Data: Discovering Knowledge through Mining and Analysis; Systematic Knowledge Management and Knowledge Discovery; Text Mining; Methodological Approach in Discovering User Search Patterns through Web Log Analysis; Knowledge Discovery in Databases Using Formal Concept Analysis; Knowledge Discovery with a Little Perspective.

    Science.gov (United States)

    Qin, Jian; Jurisica, Igor; Liddy, Elizabeth D.; Jansen, Bernard J; Spink, Amanda; Priss, Uta; Norton, Melanie J.

    2000-01-01

    These six articles discuss knowledge discovery in databases (KDD). Topics include data mining; knowledge management systems; applications of knowledge discovery; text and Web mining; text mining and information retrieval; user search patterns through Web log analysis; concept analysis; data collection; and data structure inconsistency. (LRW)

  8. Generating Artificial Event Logs with Sufficient Discriminatory Power to Compare Process Discovery Techniques

    OpenAIRE

    JOUCK, Toon; Depaire, Benoit

    2014-01-01

    Past research revealed issues with artificial event data used for comparative analysis of process mining algorithms. The aim of this research is to design, implement and validate a framework for producing artificial event logs which should increase discriminatory power of artificial event logs when evaluating process discovery techniques. artificial event logs; event log simulation; performance measurement of business processes

  9. Geomicrobial Optical Logging Detectors (GOLD)

    Science.gov (United States)

    Bramall, N. E.; Stoker, C. R.; Price, P. B.; Coates, J. D.; Allamandola, L. J.; Mattioda, A. L.

    2008-12-01

    We will present concepts for downhole instrumentation that could be used in the Deep Underground Science and Engineering Laboratory (DUSEL). We envision optical borehole-logging instruments that could monitor bacterial concentration, mineralogy, aromatic organics, temperature and oxygen concentration, allowing for the in situ monitoring of time-dependent microbial and short-scale geologic processes and provide valuable in situ data on stratigraphy to supplement core analyses, especially where instances of missing or damaged core sections make such studies difficult. Incorporated into these instruments will be a sampling/inoculation tool to allow for the recovery and/or manipulation of particularly interesting sections of the borehole wall for further study, enabling a series of microbiological studies. The borehole tools we will develop revolve around key emerging technologies and methods, some of which are briefly described below: 1) Autofluorescence Spectroscopy: Building on past instruments, we will develop a new borehole logger that searches for microbial life and organics using fluorescence spectroscopy. Many important organic compounds (e.g. PAHs) and biomolecules (e.g. aromatic amino acids, proteins, methanogenic coenzymes) fluoresce when excited with ultraviolet and visible light. Through the careful selection of excitation wavelength(s) and temporal gating parameters, a borehole logging instrument can detect and differentiate between these different compounds and the mineral matrix in which they exist. 2) Raman Spectroscopy: Though less sensitive than fluorescence spectroscopy, Raman spectroscopy is more definitive: it can provide important mineral phase distribution/proportions and other chemical data enabling studies of mineralogy and microbe-mineral interactions (when combined with fluorescence). 3) Borehole Camera: Imaging of the borehole wall with extended information in the UV, visible, and NIR for a more informative view can provide a lot of insight

  10. Engineering aspects of radiometric logging

    International Nuclear Information System (INIS)

    Huppert, P.

    1982-01-01

    Engineering problems encountered in the development of nuclear borehole logging techniques are discussed. Spectrometric techniques require electronic stability of the equipment. In addition the electronics must be capable of handling high count rates of randomly distributed pulses of fast rise time from the detector and the systems must be designed so that precise calibration is possible under field operating conditions. Components of a logging system are discussed in detail. They include the logging probe (electronics, detector, high voltage supply, preamplifier), electronic instrumentation for data collection and processing and auxiliary equipment

  11. Gamma-ray analysis for U, Th and K on bulk cutting samples from deep wells in the Danish Subbasin and the North German Basin

    International Nuclear Information System (INIS)

    Lovborg, L.

    1987-07-01

    A total of 1329 bulk cutting samples from deep wells in Denmark were analysed for U, Th and K by laboratory gamma-ray analysis. Contamination of the samples by drilling mud additives, mud solids and fall down was studied by means of a wash down experiment and by comparison with the total gamma-ray response from wireline logging. It is concluded that the inorganic geochemistry on bulk cutting samples must be applied with great caution. The data are useful for geochemical characterization of well sections and for regional geochemical correlation. Radioelement abundance logs and radioelement ratio logs are presented from 3 wells in the Danish Subbasin and 2 wells in the North German Basin. The radioelement geochemistry is discussed for the successive lithostratigraphical units and a reference radioelement profile is established for the central part of the Danish Subbasin. Finally, a model describing the relationship between common lithofacies and their U content and Th/U ratio is suggested. The model deliniates the depositional environment and the relative distances to the provenance areas. It is concluded that: (1) Uranium is mobile during deposition, but since then it is fixed by stable mineral phases at depth; (2) Thorium reflects source area characteristics and that any available ions are readily adsorbed by clay minerals. Thorium anomalies may thus serve as lithostratigraphical markers; (3) Potassium occurs in unstable rock forming mineral phases. The present distribution is controlled not only by the clastic mineral assemblage, but also by the diagenetic processes through geologic time

  12. New materials for fireplace logs

    Science.gov (United States)

    Kieselback, D. J.; Smock, A. W.

    1971-01-01

    Fibrous insulation and refractory concrete are used for logs as well as fireproof walls, incinerator bricks, planters, and roof shingles. Insulation is lighter and more shock resistant than fireclay. Lightweight slag bonded with refractory concrete serves as aggregrate.

  13. Evaluation of logging impacts on tropical rainforest in Eastern ...

    African Journals Online (AJOL)

    Various strategies and techniques have been designed and implemented to study the effects of logging activities on tropical rainforest amongst which remote sensing and GIS analysis. But there are still few measures available on the effects of industrial timber on forest ecosystem. This paper examined the impact of logging ...

  14. Acoustic sorting models for improved log segregation

    Science.gov (United States)

    Xiping Wang; Steve Verrill; Eini Lowell; Robert J. Ross; Vicki L. Herian

    2013-01-01

    In this study, we examined three individual log measures (acoustic velocity, log diameter, and log vertical position in a tree) for their ability to predict average modulus of elasticity (MOE) and grade yield of structural lumber obtained from Douglas-fir (Pseudotsuga menziesii [Mirb. Franco]) logs. We found that log acoustic velocity only had a...

  15. 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)

    2004-07-01

    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)

  16. 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)

    2005-07-01

    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.

  17. Log quality enhancement: A systematic assessment of logging company wellsite performance and log quality

    International Nuclear Information System (INIS)

    Farnan, R.A.; Mc Hattie, C.M.

    1984-01-01

    To improve the monitoring of logging company performance, computer programs were developed to assess information en masse from log quality check lists completed on wellsite by the service company engineer and Phillips representative. A study of all logging jobs performed by different service companies for Phillips in Oklahoma (panhandle excepted) during 1982 enabled several pertinent and beneficial interpretations to be made. Company A provided the best tool and crew service. Company B incurred an excessive amount of lost time related to tool failure, in particular the neutron-density tool combination. Company C, although used only three times, incurred no lost time. With a reasonable data base valid conclusions were made pertaining, for example, to repeated tool malfunctions. The actual logs were then assessed for quality

  18. The optimized log interpretation method and sweet-spot prediction of gas-bearing shale reservoirs

    Science.gov (United States)

    Tan, Maojin; Bai, Ze; Xu, Jingjing

    2017-04-01

    Shale gas is one of the most important unconventional oil and gas resources, and its lithology and reservoir type are both different from conventional reservoirs [1,2]. "Where are shale reservoirs" "How to determine the hydrocarbon potential" "How to evaluate the reservoir quality", these are some key problems in front of geophysicists. These are sweet spots prediction and quantitative evaluation. As we known, sweet spots of organic shale include geological sweet spot and engineering sweet spot. Geophysical well logging can provide a lot of in-site formation information along the borehole, and all parameters describing the sweet spots of organic shale are attained by geophysical log interpretation[2]. Based on geological and petrophysical characteristics of gas shale, the log response characteristics of gas shales are summarized. Geological sweet spot includes hydrocarbon potential, porosity, fracture, water saturation and total gas content, which can be calculated by using wireline logs[3]. Firstly, the based-logging hydrocarbon potential evaluation is carried out, and the RBF neural network method is developed to estimate the total organic carbon content (TOC), which was proved more effective and suitable than empirical formula and ΔlogR methods [4]. Next, the optimized log interpretation is achieved by using model-searching, and the mineral concentrations of kerogen, clay, feldspar and pyrite and porosity are calculated. On the other hand, engineering sweet spot of shale refers to the rock physical properties and rock mechanism parameters. Some elastic properties including volume module, shear modulus and Poisson's ratio are correspondingly determined from log interpretation, and the brittleness index (BI), effective stress and pore pressure are also estimated. BI is one of the most important engineering sweet spot parameters. A large number of instances show that the summarized log responses can accurately identify the gas-bearing shale, and the proposed RBF

  19. Pulsed neutron generator for logging

    International Nuclear Information System (INIS)

    Thibideau, F.D.

    1977-01-01

    A pulsed neutron generator for uranium logging is described. This generator is one component of a prototype uranium logging probe which is being developed by SLA to detect, and assay, uranium by borehole logging. The logging method is based on the measurement of epithermal neutrons resulting from the prompt fissioning of uranium from a pulsed source of 17.6 MeV neutrons. An objective of the prototype probe was that its diameter not exceed 2.75 inches, which would allow its use in conventional rotary drill holes of 4.75-inch diameter. This restriction limited the generator to a maximum 2.375-inch diameter. The performance requirements for the neutron generator specified that it operate with a nominal output of 5 x 10 6 neutrons/pulse at up to 100 pulses/second for a one-hour period. The development of a neutron generator meeting the preliminary design goals was completed and two prototype models were delivered to SLA. These two generators have been used by SLA to log a number of boreholes in field evaluation of the probe. The results of the field evaluations have led to the recommendation of several changes to improve the probe's operation. Some of these changes will require additional development effort on the neutron generator. It is expected that this work will be performed during 1977. The design and operation of the first prototype neutron generators is described

  20. Logística interna

    OpenAIRE

    Sousa, Paulo Teixeira de

    2002-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Produção. Essa dissertação tem como objetivo demonstrar a importância da logística interna nas organizações prestadoras de serviço. A logística é vista como um processo capaz de aumentar a eficiência organizacional através da redução dos custos operacionais bem como agiliza os processos de movimentação das mercadorias em toda cadeia de abastecimento. A logística é...

  1. Mud Logging; Control geologico en perforaciones petroliferas (Mud Logging)

    Energy Technology Data Exchange (ETDEWEB)

    Pumarega Lafuente, J.C.

    1994-12-31

    Mud Logging is an important activity in the oil field and it is a key job in drilling operations, our duties are the acquisition, collection and interpretation of the geological and engineering data at the wellsite, also inform the client immediately of any significant changes in the well. (Author)

  2. Pulsed neutron porosity logging system

    International Nuclear Information System (INIS)

    Smith, H.D. Jr.; Smith, M.P.; Schultz, W.E.

    1978-01-01

    An improved pulsed neutron porosity logging system is provided in the present invention. A logging tool provided with a 14 MeV pulsed neutron source, an epithermal neutron detector, and a fast neutron detector is moved through a borehole. Repetitive bursts of neutrons irradiate the earth formations and, during the bursts, the fast neutron population is sampled. During the interval between bursts the epithermal neutron population is sampled along with background gamma radiation due to lingering thermal neutrons. The fast and epithermal neutron population measurements are combined to provide a measurement of formation porosity

  3. Narrating illegal logging across the globe

    DEFF Research Database (Denmark)

    Winkel, G.; Leipold, S.; Buhmann, Karin

    2017-01-01

    In the last decade illegal logging has triggered the attention of policy makers and scholars of international forest governance. The issue is multifaceted, involving aspects of social and environmental sustainability, development, trade, access to markets and competitiveness. A vivid academic...... debate has resulted, exploring the nexus between markets and trade on one hand, and environmental and social sustainability on the other. The purpose of this paper is systematically assess the international policy discourse on illegal logging and legality verification policies in different regions...... of the world, drawing on the concept of policy narratives. Specifically, we analyse and compare policy narratives in Australia, Cambodia, China, the EU, Indonesia, Peru and the US. Our analysis is grounded on a rich empirical basis consisting of 260 interviews conducted by various researchers, numerous...

  4. A regularity-based modeling of oil borehole logs

    Science.gov (United States)

    Gaci, Said; Zaourar, Naima

    2013-04-01

    Multifractional Brownian motions (mBms) are successfully used to describe borehole logs behavior. These local fractal models allow to investigate the depth-evolution of regularity of the logs, quantified by the Hölder exponent (H). In this study, a regularity analysis is carried out on datasets recorded in Algerian oil boreholes located in different geological settings. The obtained regularity profiles show a clear correlation with lithology. Each lithological discontinuity corresponds to a jump in H value. Moreover, for a given borehole, all the regularity logs are significantly correlated and lead to similar lithological segmentations. Therefore, the Hölderian regularity is a robust property which can be used to characterize lithological heterogeneities. However, this study does not draw any relation between the recorded physical property and its estimated regularity degree for all the analyzed logs. Keywords: well logs, regularity, Hölder exponent, multifractional Brownian motion

  5. Soil Wetness Influences Log Skidding

    Science.gov (United States)

    William N. Darwin

    1960-01-01

    One of the least explored variables in timber harvesting is the effect of ground conditions on log production . The Southern Hardwoods Laboratory is studying this variable and its influence on performance of skidding vehicles in Southern bottom lands. The test reported here was designed to evaluate the effects of bark features on skidding coefficients, but it also...

  6. Log exports by port, 1987.

    Science.gov (United States)

    Debra D. Warren

    1989-01-01

    Volumes and average values of log exports by port have been compiled by quarter for 1987. The tables show the four Northwest customs districts by ports, species, and destinations. These data were received from the U.S. Department of Commerce too late to be published in the 1987 quarterly reports, "Production, Prices, Employment, and Trade in Northwest Forest...

  7. Postfire logging in riparian areas.

    Science.gov (United States)

    Gordon H. Reeves; Peter A. Bisson; Bruce E. Rieman; Lee E. Benda

    2006-01-01

    We reviewed the behavior of wildfire in riparian zones, primarily in the western United States, and the potential ecological consequences of postfire logging. Fire behavior in riparian zones is complex, but many aquatic and riparian organisms exhibit a suite of adaptations that allow relatively rapid recovery after fire. Unless constrained by other factors, fish tend...

  8. Determining gas hydrate distribution in sands using integrated analysis of well log and seismic data in the Terrebonne Basin, Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Hillman, Jess; Cook, Ann; Daigle, Hugh; Nole, Michael; Malinverno, Alberto

    2016-09-30

    The Terrebonne Basin is a salt bounded mini-basin in the northeast section of the Walker Ridge protraction area in the Gulf of Mexico, and the main site for an upcoming gas-hydrate focused International Ocean Discovery Program (IODP) cruise. The basin is infilled by an increasingly mud rich sedimentary sequence with several 5-15 meter gas-hydrate filled sand units of Miocene to Pliocene age overlying the up-domed salt. These gas-hydrate filled sand units can be identified in logging while drilling data from two existing wells in the Terrebonne Basin, drilled in 2009 by the Gas Hydrate Joint Industry Project (JIP) Leg 2. The sand units are cross cut by a distinct bottom-simulating reflector (BSR), and are clearly characterized by a polarity reversal in the sand units. The polarity reversal is caused by a positive gas-hydrate filled sand within the stability zone changing to negative gas-bearing sand. Using well data and calculated synthetic seismogram well ties we are able to identify several additional 1-4 meter gas-hydrate and water-saturated sand units associated with thick (100-200 m-thick), fine grained, hydrate bearing fractured units in the upper sedimentary sequence on the seismic data. Following on previous work, we propose that microbial generation of methane occurring within the fine-grained, fractured units acts as a source for gas hydrate formation in the thin sands. In contrast, it has been proposed that the gas hydrate in the 5-15 m-thick sands first discovered by the JIP was originates from a deeper thermogenic source. Through correlating hydrate occurrence in sands from well data, to amplitudes derived from the seismic data, we can estimate possible distribution of hydrate across the basin. Overall, we find the Terrebonne basin to be a complex gas hydrate system with multiple mechanisms of methane generation and migration.

  9. Hardwood log supply: a broader perspective

    Science.gov (United States)

    Iris Montague; Adri Andersch; Jan Wiedenbeck; Urs. Buehlmann

    2015-01-01

    At regional and state meetings we talk with others in our business about the problems we face: log exports, log quality, log markets, logger shortages, cash flow problems, the weather. These are familiar talking points and real and persistent problems. But what is the relative importance of these problems for log procurement in different regions of...

  10. Palm distributions for log Gaussian Cox processes

    DEFF Research Database (Denmark)

    Coeurjolly, Jean-Francois; Møller, Jesper; Waagepetersen, Rasmus Plenge

    2017-01-01

    This paper establishes a remarkable result regarding Palm distributions for a log Gaussian Cox process: the reduced Palm distribution for a log Gaussian Cox process is itself a log Gaussian Cox process that only differs from the original log Gaussian Cox process in the intensity function. This new...

  11. SU-E-J-150: Impact of Intrafractional Prostate Motion On the Accuracy and Efficiency of Prostate SBRT Delivery: A Retrospective Analysis of Prostate Tracking Log Files

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, H; Hirsch, A; Willins, J; Kachnic, J [Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Boston Medical Center and Boston University School of Medicine, Boston, MA (United States); Qureshi, M; Katz, M; Nicholas, B; Keohan, S [Boston Medical Center and Boston University School of Medicine, Boston, MA (United States); De Armas, R [Massachusetts Institute of Technology, Cambridge, MA (United States); Lu, H; Efstathiou, J; Zietman, A [Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States)

    2014-06-01

    Purpose: To measure intrafractional prostate motion by time-based stereotactic x-ray imaging and investigate the impact on the accuracy and efficiency of prostate SBRT delivery. Methods: Prostate tracking log files with 1,892 x-ray image registrations from 18 SBRT fractions for 6 patients were retrospectively analyzed. Patient setup and beam delivery sessions were reviewed to identify extended periods of large prostate motion that caused delays in setup or interruptions in beam delivery. The 6D prostate motions were compared to the clinically used PTV margin of 3–5 mm (3 mm posterior, 5 mm all other directions), a hypothetical PTV margin of 2–3 mm (2 mm posterior, 3 mm all other directions), and the rotation correction limits (roll ±2°, pitch ±5° and yaw ±3°) of CyberKnife to quantify beam delivery accuracy. Results: Significant incidents of treatment start delay and beam delivery interruption were observed, mostly related to large pitch rotations of ≥±5°. Optimal setup time of 5–15 minutes was recorded in 61% of the fractions, and optimal beam delivery time of 30–40 minutes in 67% of the fractions. At a default imaging interval of 15 seconds, the percentage of prostate motion beyond PTV margin of 3–5 mm varied among patients, with a mean at 12.8% (range 0.0%–31.1%); and the percentage beyond PTV margin of 2–3 mm was at a mean of 36.0% (range 3.3%–83.1%). These timely detected offsets were all corrected real-time by the robotic manipulator or by operator intervention at the time of treatment interruptions. Conclusion: The durations of patient setup and beam delivery were directly affected by the occurrence of large prostate motion. Frequent imaging of down to 15 second interval is necessary for certain patients. Techniques for reducing prostate motion, such as using endorectal balloon, can be considered to assure consistently higher accuracy and efficiency of prostate SBRT delivery.

  12. A compendium of P- and S-wave velocities from surface-to-borehole logging; summary and reanalysis of previously published data and analysis of unpublished data

    Science.gov (United States)

    Boore, David M.

    2003-01-01

    For over 28 years, the U.S. Geological Survey (USGS) has been acquiring seismic velocity and geologic data at a number of locations in California, many of which were chosen because strong ground motions from earthquakes were recorded at the sites. The method for all measurements involves picking first arrivals of P- and S-waves from a surface source recorded at various depths in a borehole (as opposed to noninvasive methods, such as the SASW method [e.g., Brown et al., 2002]). The results from most of the sites are contained in a series of U.S. Geological Survey Open-File Reports (see References). Until now, none of the results have been available as computer files, and before 1992 the interpretation of the arrival times was in terms of piecemeal interval velocities, with no attempt to derive a layered model that would fit the travel times in an overall sense (the one exception is Porcella, 1984). In this report I reanalyze all of the arrival times in terms of layered models for P- and for S-wave velocities at each site, and I provide the results as computer files. In addition to the measurements reported in the open-file reports, I also include some borehole results from other reports, as well as some results never before published. I include data for 277 boreholes (at the time of this writing; more will be added to the web site as they are obtained), all in California (I have data from boreholes in Washington and Utah, but these will be published separately). I am also in the process of interpreting travel time data obtained using a seismic cone penetrometer at hundreds of sites; these data can be interpreted in the same way of those obtained from surface-to-borehole logging. When available, the data will be added to the web site (see below for information on obtaining data from the World Wide Web (WWW)). In addition to the basic borehole data and results, I provide information concerning strong-motion stations that I judge to be close enough to the boreholes

  13. SU-E-J-150: Impact of Intrafractional Prostate Motion On the Accuracy and Efficiency of Prostate SBRT Delivery: A Retrospective Analysis of Prostate Tracking Log Files

    International Nuclear Information System (INIS)

    Xiang, H; Hirsch, A; Willins, J; Kachnic, J; Qureshi, M; Katz, M; Nicholas, B; Keohan, S; De Armas, R; Lu, H; Efstathiou, J; Zietman, A

    2014-01-01

    Purpose: To measure intrafractional prostate motion by time-based stereotactic x-ray imaging and investigate the impact on the accuracy and efficiency of prostate SBRT delivery. Methods: Prostate tracking log files with 1,892 x-ray image registrations from 18 SBRT fractions for 6 patients were retrospectively analyzed. Patient setup and beam delivery sessions were reviewed to identify extended periods of large prostate motion that caused delays in setup or interruptions in beam delivery. The 6D prostate motions were compared to the clinically used PTV margin of 3–5 mm (3 mm posterior, 5 mm all other directions), a hypothetical PTV margin of 2–3 mm (2 mm posterior, 3 mm all other directions), and the rotation correction limits (roll ±2°, pitch ±5° and yaw ±3°) of CyberKnife to quantify beam delivery accuracy. Results: Significant incidents of treatment start delay and beam delivery interruption were observed, mostly related to large pitch rotations of ≥±5°. Optimal setup time of 5–15 minutes was recorded in 61% of the fractions, and optimal beam delivery time of 30–40 minutes in 67% of the fractions. At a default imaging interval of 15 seconds, the percentage of prostate motion beyond PTV margin of 3–5 mm varied among patients, with a mean at 12.8% (range 0.0%–31.1%); and the percentage beyond PTV margin of 2–3 mm was at a mean of 36.0% (range 3.3%–83.1%). These timely detected offsets were all corrected real-time by the robotic manipulator or by operator intervention at the time of treatment interruptions. Conclusion: The durations of patient setup and beam delivery were directly affected by the occurrence of large prostate motion. Frequent imaging of down to 15 second interval is necessary for certain patients. Techniques for reducing prostate motion, such as using endorectal balloon, can be considered to assure consistently higher accuracy and efficiency of prostate SBRT delivery

  14. Methodology to characterize an unsampled oil interval, integrating PVT (Pressure/Volumen/Temperature) analysis and production log; Metodologia para caracterizacao de oleo de intervalo nao-amostrado, integrando analise PVT e perfil de producao

    Energy Technology Data Exchange (ETDEWEB)

    Marcon, Diogo Reato; Souza, Ana Paula Martins de; Vieira, Alexandre J.M. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2008-07-01

    This work presents a new methodology for characterizing an unsampled oil interval, using basically production log data and PVT analyses available in the well. The methodology was applied to a real case, where the live oil samples were collected during a well test run in three different depths, revealing some evidence of a compositional grading due to gravity. Each individual sample was a mixture of the fluid produced from the reservoir bottom to the sampling point, since the whole interval was perforated and the isolation had to be made with a packer. The first sample was corresponding to the mixture of lower and all upper oils. The other two samples are only the heavier and that oil with part of the one from the upper interval. In order to identify the fluid properties from the upper interval, needed for production development studies, the following procedure was devised: equation-of-state tuning, reproducing the sampled fluid properties; conversion of volumetric flowrates from production log into mass and molar flowrates; flowrate ratio calculation, between the upper and lower intervals; upper interval fluid composition estimative; upper interval fluid properties simulation, using the previously tuned equation-of-state, thus generating what was considered a representative, synthetic PVT analysis. (author)

  15. Uranium logging in earth formations

    International Nuclear Information System (INIS)

    Givens, W.W.

    1979-01-01

    A technique is provided for assaying the formations surrounding a borehole for uranium. A borehole logging tool cyclically irradiates the formations with neutrons and responds to neutron fluxes produced during the period of time that prompt neutrons are being produced by the neutron fission of uranium in the formations. A borehole calibration tool employs a steady-state (continuous output) neutron source, firstly, to produce a response to neutron fluxes in models having known concentrations of uranium and, secondly, to to produce a response to neutron fluxes in the formations surrounding the borehole. The neutron flux responses of the borehole calibration tool in both the model and the formations surrounding the borehole are utilized to correct the neutron flux response of the borehole logging tool for the effects of epithermal/thermal neutron moderation, scattering, and absorption within the borehole itself

  16. Logística empresarial

    OpenAIRE

    Feres Sahid

    1987-01-01

    RESUMEN El concepto logístico, se pudo ver reflejado con exactitud desde el punto de vista etimológico e histórico a través de la revista de la E.A.N; ya que  tiene cierto carácter militar que lo hace característico a la gestión empresarial y de esto se formula un debate definitivo de este concepto.

  17. Logística empresarial

    Directory of Open Access Journals (Sweden)

    Feres Sahid

    1987-04-01

    Full Text Available RESUMEN El concepto logístico, se pudo ver reflejado con exactitud desde el punto de vista etimológico e histórico a través de la revista de la E.A.N; ya que  tiene cierto carácter militar que lo hace característico a la gestión empresarial y de esto se formula un debate definitivo de este concepto.

  18. Chemical logging of geothermal wells

    Science.gov (United States)

    Allen, C.A.; McAtee, R.E.

    The presence of geothermal aquifers can be detected while drilling in geothermal formations by maintaining a chemical log of the ratio of the concentrations of calcium to carbonate and bicarbonate ions in the return drilling fluid. A continuous increase in the ratio of the concentrations of calcium to carbonate and bicarbonate ions is indicative of the existence of a warm or hot geothermal aquifer at some increased depth.

  19. Neutron capture in borehole logging

    International Nuclear Information System (INIS)

    Randall, R.R.

    1981-01-01

    The use is described of a pulsed source of fast neutrons and a radiation detector to measure the thermal neutron population decay rate in a well logging instrument. The macroscopic neutron absorption cross-section is calculated by taking the natural logarithm of the ratio of the detected radiation counts occurring within two measurement intervals of fixed duration and starting at a fixed time after a neutron burst. (U.K.)

  20. A Method for Visualizing Transaction Logs of a Faceted OPAC

    Directory of Open Access Journals (Sweden)

    Xi Niu

    2010-12-01

    Full Text Available The authors introduce a method for visualizing user transaction logs from a library catalog application. Simple visualization supporting intuitive or qualitative analysis to quickly make sense of complicated patterns can be a useful supplement or alternative to more common quantitative analysis. To this end, a visual flowchart is created illustrating an individual user session. This visualization can be used to qualitatively grasp user behavior within the application, possibly as an aid to identifying patterns or clusters of use. These flowcharts are created by automatically pre-processing apache transaction logs into an XML representation of meaningful user actions, which are then converted via JavaScript in a web browser to HTML table based flowcharts. The particular toolkit introduced is named Visualization for Understanding Transaction Logs (VUTL, and is available with an open source license. The toolkit has been prototyped with logs from the catalog applications of several academic and one public library.

  1. Ordinal Log-Linear Models for Contingency Tables

    Directory of Open Access Journals (Sweden)

    Brzezińska Justyna

    2016-12-01

    Full Text Available A log-linear analysis is a method providing a comprehensive scheme to describe the association for categorical variables in a contingency table. The log-linear model specifies how the expected counts depend on the levels of the categorical variables for these cells and provide detailed information on the associations. The aim of this paper is to present theoretical, as well as empirical, aspects of ordinal log-linear models used for contingency tables with ordinal variables. We introduce log-linear models for ordinal variables: linear-by-linear association, row effect model, column effect model and RC Goodman’s model. Algorithm, advantages and disadvantages will be discussed in the paper. An empirical analysis will be conducted with the use of R.

  2. Linking downhole logging data with geology and drilling /coring operations - Example from Chicxulub Expedition 364.

    Science.gov (United States)

    Lofi, Johanna; Smith, Dave; Delahunty, Chris; Le Ber, Erwan; Mellet, Claire; Brun, Laurent; Henry, Gilles; Paris, Jehanne

    2017-04-01

    Expedition 364 was a joint IODP/ICDP mission specific platform expedition to explore the Chicxulub impact crater buried below the Yucatán continental shelf. In April and May 2016, our Expedition drilled a single borehole at Site M0077A into the crater's peak ring. It allowed recovering 303 excellent quality cores from 505.7 to 1334.7 meters below sea floor and acquiring more than 5.8 km of high resolution open hole logs. Downhole logs are rapidly collected, continuous with depth, and measured in situ; these data are classically interpreted in terms of stratigraphy, lithology, porosity, fluid content, geochemical composition and structure of the formation drilled. Downhole logs also allow assessing borehole quality (eg. shape and trajectory), and can provide assistance for decision support during drilling operations. In this work, Expedition 364 downhole logs are used to improve our understanding of the drilling/coring operation history. Differentiating between natural geological features and borehole artifacts are also critical for data quality assessment. The set of downhole geophysical tools used during Expedition 364 was constrained by the scientific objectives, drilling/coring technique, hole conditions and temperature at the drill site. Wireline logging data were acquired with slimline tools in three logging phases at intervals 0-503, 506-699 and 700-1334 mbsf. Logs were recorded either with standalone logging tools or, for the first time in IODP, with stackable slimline tools. Log data included total gamma radiation, sonic velocity, acoustic and optical borehole images, resistivity, conductivity, magnetic susceptibility, caliper and borehole fluid parameters. The majority of measurements were performed in open borehole conditions. During the drilling operations some problems were encountered directly linked to the geology of the drilled formation. For example, two zones of mud circulation losses correlate in depth with the presence of karst cavities or open

  3. Accurately determining log and bark volumes of saw logs using high-resolution laser scan data

    Science.gov (United States)

    R. Edward Thomas; Neal D. Bennett

    2014-01-01

    Accurately determining the volume of logs and bark is crucial to estimating the total expected value recovery from a log. Knowing the correct size and volume of a log helps to determine which processing method, if any, should be used on a given log. However, applying volume estimation methods consistently can be difficult. Errors in log measurement and oddly shaped...

  4. AUTOMATED TECHNIQUE FOR CREATING LITHOLOGIC LOG PLOTS

    Directory of Open Access Journals (Sweden)

    Kristijan Posavec

    2006-12-01

    Full Text Available Paper presents automated technique for creating lithologic log plots. Technique is based on three computer tools: Microsoft (MS Access program, LogPlot program, and Visual Basic (VB macros for MS Excel. MS Access ensures professional storage of lithologic data which can be in that way easier and faster entered, searched, updated, and also used for different purposes, while LogPlot provides tools for creating lithologic log plots. VB macros enable transfer of lithologic data from MS Access to LogPlot. Data stored in MS Access are exported in ASCII files which are later used by LogPlot for creation of lithologic log plots. Presented concept facilitates creation of lithologic log plots, and automated technique enables processing of a large number of data i.e. creation of lareg number lithologic log plots in a short period of time (the paper is published in Croatian.

  5. 76 FR 24504 - Agency Information Collection Activities: BioWatch Filter Holder Log

    Science.gov (United States)

    2011-05-02

    ... Log AGENCY: Department of Homeland Security, DHS. ACTION: 60-Day Notice and request for comments... transportation to local laboratories for sample analysis. A standard filter log form is completed for each sample... preparation of the filter log form and other documentation. The creation of a written record for each sample...

  6. 76 FR 42130 - Agency Information Collection Activities: BioWatch Filter Holder Log

    Science.gov (United States)

    2011-07-18

    ... Log AGENCY: Department of Homeland Security. ACTION: 30-Day Notice and request for comments; Extension... transportation to local laboratories for sample analysis. A standard filter log form is completed for each sample... preparation of the filter log form and other documentation. The creation of a written record for each sample...

  7. Predicting internal yellow-poplar log defect features using surface indicators

    Science.gov (United States)

    R. Edward Thomas

    2008-01-01

    Determining the defects that are located within the log is crucial to understanding the tree/log resource for efficient processing. However, existing means of doing this non-destructively requires the use of expensive X-ray/CT, MRI, or microwave technology. These methods do not lend themselves to fast, efficient, and cost-effective analysis of logs and tree stems in...

  8. Extracting the Textual and Temporal Structure of Supercomputing Logs

    Energy Technology Data Exchange (ETDEWEB)

    Jain, S; Singh, I; Chandra, A; Zhang, Z; Bronevetsky, G

    2009-05-26

    Supercomputers are prone to frequent faults that adversely affect their performance, reliability and functionality. System logs collected on these systems are a valuable resource of information about their operational status and health. However, their massive size, complexity, and lack of standard format makes it difficult to automatically extract information that can be used to improve system management. In this work we propose a novel method to succinctly represent the contents of supercomputing logs, by using textual clustering to automatically find the syntactic structures of log messages. This information is used to automatically classify messages into semantic groups via an online clustering algorithm. Further, we describe a methodology for using the temporal proximity between groups of log messages to identify correlated events in the system. We apply our proposed methods to two large, publicly available supercomputing logs and show that our technique features nearly perfect accuracy for online log-classification and extracts meaningful structural and temporal message patterns that can be used to improve the accuracy of other log analysis techniques.

  9. MI-GWAS: a SAS platform for the analysis of inherited and maternal genetic effects in genome-wide association studies using log-linear models

    OpenAIRE

    Mitchell Laura E; Agopian AJ

    2011-01-01

    Abstract Background Several platforms for the analysis of genome-wide association data are available. However, these platforms focus on the evaluation of the genotype inherited by affected (i.e. case) individuals, whereas for some conditions (e.g. birth defects) the genotype of the mothers of affected individuals may also contribute to risk. For such conditions, it is critical to evaluate associations with both the maternal and the inherited (i.e. case) genotype. When genotype data are availa...

  10. Neutron borehole logging correction technique

    International Nuclear Information System (INIS)

    Goldman, L.H.

    1978-01-01

    In accordance with an illustrative embodiment of the present invention, a method and apparatus is disclosed for logging earth formations traversed by a borehole in which an earth formation is irradiated with neutrons and gamma radiation produced thereby in the formation and in the borehole is detected. A sleeve or shield for capturing neutrons from the borehole and producing gamma radiation characteristic of that capture is provided to give an indication of the contribution of borehole capture events to the total detected gamma radiation. It is then possible to correct from those borehole effects the total detected gamma radiation and any earth formation parameters determined therefrom

  11. An innovative OSCE clinical log station: a quantitative study of its influence on Log use by medical students.

    Science.gov (United States)

    Hudson, Judith N; Rienits, Helen; Corrin, Linda; Olmos, Martin

    2012-11-12

    A Clinical Log was introduced as part of a medical student learning portfolio, aiming to develop a habit of critical reflection while learning was taking place, and provide feedback to students and the institution on learning progress. It was designed as a longitudinal self-directed structured record of student learning events, with reflection on these for personal and professional development, and actions planned or taken for learning.As incentive was needed to encourage student engagement, an innovative Clinical Log station was introduced in the OSCE, an assessment format with established acceptance at the School. This study questions: How does an OSCE Clinical Log station influence Log use by students? The Log station was introduced into the formative, and subsequent summative, OSCEs with careful attention to student and assessor training, marking rubrics and the standard setting procedure. The scoring process sought evidence of educational use of the log, and an ability to present and reflect on key learning issues in a concise and coherent manner. Analysis of the first cohort's Log use over the four-year course (quantified as number of patient visits entered by all students) revealed limited initial use. Usage was stimulated after introduction of the Log station early in third year, with some improvement during the subsequent year-long integrated community-based clerkship. Student reflection, quantified by the mean number of characters in the 'reflection' fields per entry, peaked just prior to the final OSCE (mid-Year 4). Following this, very few students continued to enter and reflect on clinical experience using the Log. While the current study suggested that we can't assume students will self-reflect unless such an activity is included in an assessment, ongoing work has focused on building learner and faculty confidence in the value of self-reflection as part of being a competent physician.

  12. An innovative OSCE clinical log station: a quantitative study of its influence on Log use by medical students

    Directory of Open Access Journals (Sweden)

    Hudson Judith N

    2012-11-01

    Full Text Available Abstract Background A Clinical Log was introduced as part of a medical student learning portfolio, aiming to develop a habit of critical reflection while learning was taking place, and provide feedback to students and the institution on learning progress. It was designed as a longitudinal self-directed structured record of student learning events, with reflection on these for personal and professional development, and actions planned or taken for learning. As incentive was needed to encourage student engagement, an innovative Clinical Log station was introduced in the OSCE, an assessment format with established acceptance at the School. This study questions: How does an OSCE Clinical Log station influence Log use by students? Methods The Log station was introduced into the formative, and subsequent summative, OSCEs with careful attention to student and assessor training, marking rubrics and the standard setting procedure. The scoring process sought evidence of educational use of the log, and an ability to present and reflect on key learning issues in a concise and coherent manner. Results Analysis of the first cohort’s Log use over the four-year course (quantified as number of patient visits entered by all students revealed limited initial use. Usage was stimulated after introduction of the Log station early in third year, with some improvement during the subsequent year-long integrated community-based clerkship. Student reflection, quantified by the mean number of characters in the ‘reflection’ fields per entry, peaked just prior to the final OSCE (mid-Year 4. Following this, very few students continued to enter and reflect on clinical experience using the Log. Conclusion While the current study suggested that we can’t assume students will self-reflect unless such an activity is included in an assessment, ongoing work has focused on building learner and faculty confidence in the value of self-reflection as part of being a competent

  13. An innovative OSCE clinical log station: a quantitative study of its influence on Log use by medical students

    Science.gov (United States)

    2012-01-01

    Background A Clinical Log was introduced as part of a medical student learning portfolio, aiming to develop a habit of critical reflection while learning was taking place, and provide feedback to students and the institution on learning progress. It was designed as a longitudinal self-directed structured record of student learning events, with reflection on these for personal and professional development, and actions planned or taken for learning. As incentive was needed to encourage student engagement, an innovative Clinical Log station was introduced in the OSCE, an assessment format with established acceptance at the School. This study questions: How does an OSCE Clinical Log station influence Log use by students? Methods The Log station was introduced into the formative, and subsequent summative, OSCEs with careful attention to student and assessor training, marking rubrics and the standard setting procedure. The scoring process sought evidence of educational use of the log, and an ability to present and reflect on key learning issues in a concise and coherent manner. Results Analysis of the first cohort’s Log use over the four-year course (quantified as number of patient visits entered by all students) revealed limited initial use. Usage was stimulated after introduction of the Log station early in third year, with some improvement during the subsequent year-long integrated community-based clerkship. Student reflection, quantified by the mean number of characters in the ‘reflection’ fields per entry, peaked just prior to the final OSCE (mid-Year 4). Following this, very few students continued to enter and reflect on clinical experience using the Log. Conclusion While the current study suggested that we can’t assume students will self-reflect unless such an activity is included in an assessment, ongoing work has focused on building learner and faculty confidence in the value of self-reflection as part of being a competent physician. PMID:23140250

  14. 47 CFR 73.1820 - Station log.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Station log. 73.1820 Section 73.1820... Rules Applicable to All Broadcast Stations § 73.1820 Station log. (a) Entries must be made in the station log either manually by a person designated by the licensee who is in actual charge of the...

  15. 29 CFR 1917.18 - Log handling.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Log handling. 1917.18 Section 1917.18 Labor Regulations...) MARINE TERMINALS Marine Terminal Operations § 1917.18 Log handling. (a) The employer shall ensure that structures (bunks) used to contain logs have rounded corners and rounded structural parts to avoid sling...

  16. Linking log quality with product performance

    Science.gov (United States)

    D. W. Green; Robert Ross

    1997-01-01

    In the United States, log grading procedures use visual assessment of defects, in relation to the log scaling diameter, to estimate the yield of lumber that maybe expected from the log. This procedure was satisfactory when structural grades were based only on defect size and location. In recent years, however, structural products have increasingly been graded using a...

  17. Selective logging and its relation to deforestation

    Science.gov (United States)

    Gregory P. Asner; Michael Keller; Marco Lentini; Frank Merry; Souza Jr. Carlos

    2009-01-01

    Selective logging is a major contributor to the social, economic, and ecological dynamics of Brazilian Amazonia. Logging activities have expanded from low-volume floodplain harvests in past centuries to high-volume operations today that take about 25 million m3 of wood from the forest each year. The most common high-impact conventional and often illegal logging...

  18. A neutron well logging system

    International Nuclear Information System (INIS)

    1980-01-01

    A pulsed neutron well logging system using a sealed off neutron generator tube is provided with a programmable digital neutron output control system. The control system monitors the target beam current and compares a function of this current with a pre-programmed control function to develop a control signal for the neutron generator. The control signal is used in a series regulator to control the average replenisher current of the neutron generator tube. The programmable digital control system of the invention also provides digital control signals as a function of time to provide ion source voltages. This arrangement may be utilized to control neutron pulses durations and repetition rates or to produce other modulated wave forms for intensity modulating the output of the neutron generator as a function of time. (Auth.)

  19. Decomposable log-linear models

    DEFF Research Database (Denmark)

    Eriksen, Poul Svante

    can be characterized by a structured set of conditional independencies between some variables given some other variables. We term the new model class decomposable log-linear models, which is illustrated to be a much richer class than decomposable graphical models.It covers a wide range of non...... The present paper considers discrete probability models with exact computational properties. In relation to contingency tables this means closed form expressions of the maksimum likelihood estimate and its distribution. The model class includes what is known as decomposable graphicalmodels, which......-hierarchical models, models with structural zeroes, models described by quasi independence and models for level merging. Also, they have a very natural interpretation as they may be formulated by a structured set of conditional independencies between two events given some other event. In relation to contingency...

  20. Computer planning tools applied to a cable logging research study

    Science.gov (United States)

    Chris B. LeDoux; Penn A. Peters

    1985-01-01

    Contemporary harvest planning software was used in planning the layout of cable logging units for a production study of the Clearwater Yarder in upstate New York. Planning software, including payload analysis and digital terrain models, allowed researchers to identify layout and yarding problems before the experiment. Analysis of proposed ground profiles pinpointed the...

  1. Static dictionaries on AC0 RAMs: query time (√log n/log log n) is necessary and sufficient

    DEFF Research Database (Denmark)

    Andersson, Arne; Miltersen, Peter Bro; Riis, Søren

    1996-01-01

    In this paper we consider solutions to the static dictionary problem on AC0 RAMs, i.e. random access machines where the only restriction on the finite instruction set is that all computational instructions are in AC0. Our main result is a tight upper and lower bound of θ(√log n/log log n) on the ......In this paper we consider solutions to the static dictionary problem on AC0 RAMs, i.e. random access machines where the only restriction on the finite instruction set is that all computational instructions are in AC0. Our main result is a tight upper and lower bound of θ(√log n/log log n......, we show a tradeoff between time and circuit depth under the unit-cost assumption: any RAM instruction set which permits a linear space, constant query time solution to the static dictionary problem must have an instruction of depth Ω(log w/log log to), where w is the word size of the machine (and log...

  2. Technical difficulties of logging while drilling in carbonate reservoirs and the countermeasures: A case study from the Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Shudong Zhang

    2015-12-01

    Full Text Available In the Sichuan Basin, carbonate reservoirs are characterized by deep burial depth and strong heterogeneity, so it is difficult to conduct structure steering, pore space reservoir tracking and trajectory control in the process of geosteering logging while drilling. In this paper, a series of corresponding techniques for structure, reservoir and formation tracking were proposed after analysis was conducted on multiple series of carbonate strata in terms of their geologic and logging response characteristics. And investigation was performed on the adaptabilities of the following logging technologies to geosteering while drilling, including gamma ray imaging while drilling, resistivity imaging while drilling, density imaging while drilling, gamma ray logging while drilling, resistivity logging while drilling, neutron logging while drilling and density logging while drilling. After while drilling information was thoroughly analyzed, the logging suites for four common types of complicated reservoirs (thin layered reservoirs, thick massive reservoirs, denuded karst reservoirs and shale gas reservoirs were optimized, and five logging combinations suitable for different formations and reservoirs were proposed, including gamma ray logging + porosity + resistivity imaging, gamma ray logging + resistivity imaging, gamma ray logging + porosity + resistivity logging, gamma ray imaging + resistivity logging, and gamma ray logging. Field application indicates that it is of great reference and application value to use this method for the first time to summarize logging while drilling combinations for different types of carbonate reservoirs.

  3. Effects of Adjuvant Mental Practice on Affected Upper Limb Function Following a Stroke: Results of Three-Dimensional Motion Analysis, Fugl-Meyer Assessment of the Upper Extremity and Motor Activity Logs.

    Science.gov (United States)

    Oh, Hyun Seung; Kim, Eun Joo; Kim, Doo Young; Kim, Soo Jeong

    2016-06-01

    To investigate the effects of adjuvant mental practice (MP) on affected upper limb function following a stroke using three-dimensional (3D) motion analysis. In this AB/BA crossover study, we studied 10 hemiplegic patients who had a stroke within the past 6 months. The patients were randomly allocated to two groups: one group received MP combined with conventional rehabilitation therapy for the first 3 weeks followed by conventional rehabilitation therapy alone for the final 3 weeks; the other group received the same therapy but in reverse order. The MP tasks included drinking from a cup and opening a door. MP was individually administered for 20 minutes, 3 days a week for 3 weeks. To assess the tasks, we used 3D motion analysis and three additional tests: the Fugl-Meyer Assessment of the upper extremity (FMA-UE) and the motor activity logs for amount of use (MAL-AOU) and quality of movement (MAL-QOM). Assessments were performed immediately before treatment (T0), 3 weeks into treatment (T1), and 6 weeks into treatment (T2). Based on the results of the 3D motion analysis and the FMA-UE index (p=0.106), the MAL-AOU scale (p=0.092), and MAL-QOM scale (p=0.273), adjuvant MP did not result in significant improvements. Adjuvant MP had no significant effect on upper limb function following a stroke, according to 3D motion analysis and three clinical assessment tools (the FMA-UE index and the two MAL scales). The importance of this study is its use of objective 3D motion analysis to evaluate the effects of MP. Further studies will be needed to validate these findings.

  4. Determining Partition Coefficient (Log P), Distribution Coefficient (Log D) and Ionization Constant (pKa) in Early Drug Discovery.

    Science.gov (United States)

    Bharate, Sonali S; Kumar, Vikas; Vishwakarma, Ram A

    2016-01-01

    An early prediction of physicochemical properties is highly desirable during drug discovery to find out a viable lead candidate. Although there are several methods available to determine partition coefficient (log P), distribution coefficient (log D) and ionization constant (pKa), none of them involves simple and fixed, miniaturized protocols for diverse set of compounds. Therefore, it is necessary to establish simple, uniform and medium-throughput protocols requiring small sample quantities for the determination of these physicochemical properties. Log P and log D were determined by shake flask method, wherein, the compound was partitioned between presaturated noctanol and water phase (water/PBS pH 7.4) and the concentration of compound in each phase was determined by HPLC. The pKa determination made use of UV spectrophotometric analysis in a 96-well microtiter plate containing a series of aqueous buffers ranging from pH 1.0 to 13.0. The medium-throughput miniaturized protocols described herein, for determination of log P, log D and pKa, are straightforward to set up and require very small quantities of sample (< 5 mg for all three properties). All established protocols were validated using diverse set of compounds.

  5. TECHNICAL AND ECONOMICAL ANALYSIS OF LOGGING CONTRACTORS

    Directory of Open Access Journals (Sweden)

    Abilio Donizetti de Morais Filho

    2009-09-01

    Full Text Available The objective of this study was to describe the financial conditions of forestry contractors, concerning life quality aspects, condition of work and equipments, operational costs, and economic credit to invest in new technologies. Five companies had been analyzed, with an annual income between US$ 400,000.00 and US$ 1,720,000.00, with an average of US$ 950,000.00. The number of employees varied between 33 and 181, and the companies were classified in terms of size as: one small, two average, and two big. The main difficulties to invest in new machines were high financial taxes, more than 12% an year, and a lack of long term contracts to guarantee the payment capability. It was observed that the contractors did not consider the capital remuneration and a correct depreciation of machines, resulting in an average machine life higher than 10 years. The final conclusions were that the costs were above the paid values for the services, when computed the depreciation and capital remuneration, with negative results in the financial analyzes of three companies. Finally, the mechanization process increased the workers life quality, however, the annual income was around US$ 2,112.00 per worker, approximately 39% lower than the average Brazilian population.

  6. Log curve amplitude slicing: Visualization of well log amplitudes for paleogeographic reconstruction of the Middle Devonian Traverse Group, Michigan Basin

    Science.gov (United States)

    Wylie, Albert Sidney, Jr.

    Well log curve shapes and amplitude trends are routinely used to correlate and map formations and reservoirs across petroleum basins or fields. The methods typically employed for correlation and mapping fail, however, to make full use of the vertical resolution of well log curves. A new technique, log curve amplitude slicing (LCAS) facilitates correlation by generating a series of subhorizontal slices through the log curves using sample-by-sample analysis of log curve amplitudes in all wells between two correlative time-surfaces. The slices represent approximate time lines and are relative chronostratigraphic surfaces that can be gridded and contoured to show trends and patterns in log curve amplitudes in map view. When appropriate logs are used (e.g. gamma ray, photoelectric effect, resistivity), the slices show the inferred distribution of lithofacies at the time of deposition. Animation allows visualization of changes in the distribution of lithofacies between successive slices. The log curves can be sliced through the interval of interest from the top-down, from the bottom-up, or proportionally depending upon the sequence stratigraphic interpretation. Application of the LCAS technique facilitates correlation because it highlights trends in log curve amplitudes that are not apparent using traditional methods to display and compare log curves. Gamma ray log data from 199 wells are used in this dissertation to identify the location, relative timing, and extent of significant fine-grained clastic influx into the carbonate/evaporite-dominated Michigan Basin during deposition of the Middle Devonian Traverse Group. LCAS maps are combined with outcrop stratigraphy to reconstruct the depositional history of the Traverse Group and to develop a relative water depth curve for the Michigan Basin during the Middle Devonian. Comparison of the relative water depth curve to a eustatic sea level curve suggests that although sea level fall may have resulted in formation of

  7. [Using log-binomial model for estimating the prevalence ratio].

    Science.gov (United States)

    Ye, Rong; Gao, Yan-hui; Yang, Yi; Chen, Yue

    2010-05-01

    To estimate the prevalence ratios, using a log-binomial model with or without continuous covariates. Prevalence ratios for individuals' attitude towards smoking-ban legislation associated with smoking status, estimated by using a log-binomial model were compared with odds ratios estimated by logistic regression model. In the log-binomial modeling, maximum likelihood method was used when there were no continuous covariates and COPY approach was used if the model did not converge, for example due to the existence of continuous covariates. We examined the association between individuals' attitude towards smoking-ban legislation and smoking status in men and women. Prevalence ratio and odds ratio estimation provided similar results for the association in women since smoking was not common. In men however, the odds ratio estimates were markedly larger than the prevalence ratios due to a higher prevalence of outcome. The log-binomial model did not converge when age was included as a continuous covariate and COPY method was used to deal with the situation. All analysis was performed by SAS. Prevalence ratio seemed to better measure the association than odds ratio when prevalence is high. SAS programs were provided to calculate the prevalence ratios with or without continuous covariates in the log-binomial regression analysis.

  8. Diagraphies de cimentation : vers une analyse de la qualité du contact ciment-formation Cement Logging: Toward an Analysis of the Quality of Cement-Formation Bonding

    Directory of Open Access Journals (Sweden)

    Isambourg P.

    2006-11-01

    specialists (VDL tool. The greatest progress that could be made with cementing logs was to detect defects in the cement-formation interface. This is what we have done within the framework of a project financed by ARTEP (Association de Recherche sur les Techniques d'Exploitation du Pétrole, made up of Total, Gaz de France (GDF, Institut Français du Pétrole (IFP and Elf Aquitaine Production (EAP. Laboratory experiments performed in the Fluid Analysis Service at Boussens involved the injecting of cement between a casing and a simulated formation, with or without the presence of mud having varying thicknesses. Fast or slow formations as well as fast or slow cements were used. The ultrasonic echoes obtained by a ceramic CET sonde were recorded and analyzed. Both theory and the experiments showed that ultrasonic echoes are modified in the presence of mud and/or gas. The relations between the shape of the ultrasonic wave and presence of mud and gas between the cement and the formation were determined. A processing procedure is proposed with its limitations. Cementing Quality : If we had to set forth a quality criterion for cementing, we would say: For cementing to be considered as being of good quality, the cement sheath must be at least as leakproof as the formation it replaces. When a borehole is drilled, different zones are effectively brought into communication. The initial isolation will be established by the casing + cement sheath. This function will thus be correctly ensured if this combination lets pass only the start of a fluid leak (water, oil, gas that is less than or equal to what is allowed by an equivalent section of formation drilled through. Naturally, this concept is mainly applied to sensitive zones, e. g. such as the overburden of a reservoir. However, it should be noted that this concept is also applied to the reservoir itself and not only to the overburden. Indeed, a leaky cement sheath at the level of a reservoir with relatively low permeability could, for

  9. Quantitative analysis of senile plaques in Alzheimer disease: observation of log-normal size distribution and molecular epidemiology of differences associated with apolipoprotein E genotype and trisomy 21 (Down syndrome).

    Science.gov (United States)

    Hyman, B T; West, H L; Rebeck, G W; Buldyrev, S V; Mantegna, R N; Ukleja, M; Havlin, S; Stanley, H E

    1995-04-11

    The discovery that the epsilon 4 allele of the apolipoprotein E (apoE) gene is a putative risk factor for Alzheimer disease (AD) in the general population has highlighted the role of genetic influences in this extremely common and disabling illness. It has long been recognized that another genetic abnormality, trisomy 21 (Down syndrome), is associated with early and severe development of AD neuropathological lesions. It remains a challenge, however, to understand how these facts relate to the pathological changes in the brains of AD patients. We used computerized image analysis to examine the size distribution of one of the characteristic neuropathological lesions in AD, deposits of A beta peptide in senile plaques (SPs). Surprisingly, we find that a log-normal distribution fits the SP size distribution quite well, motivating a porous model of SP morphogenesis. We then analyzed SP size distribution curves in genotypically defined subgroups of AD patients. The data demonstrate that both apoE epsilon 4/AD and trisomy 21/AD lead to increased amyloid deposition, but by apparently different mechanisms. The size distribution curve is shifted toward larger plaques in trisomy 21/AD, probably reflecting increased A beta production. In apoE epsilon 4/AD, the size distribution is unchanged but the number of SP is increased compared to apoE epsilon 3, suggesting increased probability of SP initiation. These results demonstrate that subgroups of AD patients defined on the basis of molecular characteristics have quantitatively different neuropathological phenotypes.

  10. Characterization of reservoir fractures using conventional geophysical logging

    Directory of Open Access Journals (Sweden)

    Paitoon Laongsakul

    2011-04-01

    Full Text Available In hydrocarbon exploration fractures play an important role as possible pathways for the hydrocarbon flow and bythis enhancing the overall formation’s permeability. Advanced logging methods for fracture analysis, like the boreholeacoustic televiewer and Formation Microscanner (FMS are available, but these are additional and expensive tools. However,open and with water or hydrocarbon filled fractures are also sensitive to electrical and other conventional logging methods.For this study conventional logging data (electric, seismic, etc were available plus additional fracture information from FMS.Taking into account the borehole environment the results show that the micro-spherically focused log indicates fractures byshowing low resistivity spikes opposite open fractures, and high resistivity spikes opposite sealed ones. Compressional andshear wave velocities are reduced when passing trough the fracture zone, which are assumed to be more or less perpendicularto borehole axis. The photoelectric absorption curve exhibit a very sharp peak in front of a fracture filled with bariteloaded mud cake. The density log shows low density spikes that are not seen by the neutron log, usually where fractures,large vugs, or caverns exist. Borehole breakouts can cause a similar effect on the logging response than fractures, but fracturesare often present when this occurs. The fracture index calculation by using threshold and input weight was calculatedand there was in general a good agreement with the fracture data from FMS especially in fracture zones, which mainlycontribute to the hydraulic system of the reservoir. Finally, the overall results from this study using one well are promising,however further research in the combination of different tools for fracture identification is recommended as well as the useof core for further validation.

  11. Comparison of Log-Pearson Type III and Gumbel Probability ...

    African Journals Online (AJOL)

    In this study, the extreme value Type 1 (Gumbel) and Log-Pearson Type III probability distributions have been alternatively utilized to perform flood frequency analysis on the peak annual series discharge data of Ikpoba River at Benin City for the water years 1989 to 2000. The predicted design floods by alternative models ...

  12. Log-concavity of the genus polynomials of Ringel Ladders

    Directory of Open Access Journals (Sweden)

    Jonathan L Gross

    2015-10-01

    Full Text Available A Ringel ladder can be formed by a self-bar-amalgamation operation on a symmetric ladder, that is, by joining the root vertices on its end-rungs. The present authors have previously derived criteria under which linear chains of copies of one or more graphs have log-concave genus polyno- mials. Herein we establish Ringel ladders as the first significant non-linear infinite family of graphs known to have log-concave genus polynomials. We construct an algebraic representation of self-bar-amalgamation as a matrix operation, to be applied to a vector representation of the partitioned genus distribution of a symmetric ladder. Analysis of the resulting genus polynomial involves the use of Chebyshev polynomials. This paper continues our quest to affirm the quarter-century-old conjecture that all graphs have log-concave genus polynomials.

  13. Processing of logging data from nuclear tools

    International Nuclear Information System (INIS)

    Oelgaard, P.L.; Petersen, R.

    1988-07-01

    When raw data, e.g. counts or count rates, have been obtained with nuclear logging tools, they have to be processed in order to yield the desired formation properties. Little information is available on this processing. However, it is necessary to understand the processing procedure in order to be able to evaluate its physical correctness, and to understand which corrections are involved. For this reason an analysis has been performed of two sets of field data obtained with neutron porosity and gamma density tools and one data set obtained with a pulsed-neutron capture-gamma tool. Through this analysis it is believed that full insight in the processing of data from the neutron porosity and the gamma density tools has been achieved. The same is not quite the case for the pulsed neutron capture-gamma tool, possibly due to lack of the necessary data. The analysis has also revealed doubt about the physical correctness of some of the features of the processing procedure. (author)

  14. SOME LIMIT-THEOREMS IN LOG DENSITY

    NARCIS (Netherlands)

    BERKES, [No Value; DEHLING, H

    Motivated by recent results on pathwise central limit theorems, we study in a systematic way log-average versions of classical limit theorems. For partial sums S(k) of independent r.v.'s we prove under mild technical conditions that (1/log N)SIGMA(k less-than-or-equal-to N)(1/k)I{S(k)/a(k)

  15. Utilization and cost for animal logging operations

    Science.gov (United States)

    Suraj P. Shrestha; Bobby L. Lanford

    2001-01-01

    Forest harvesting with animals is a labor-intensive operation. Due to the development of efficient machines and high volume demands from the forest products industry, mechanization of logging developed very fast, leaving behind the traditional horse and mule logging. It is expensive to use machines on smaller woodlots, which require frequent moves if mechanically...

  16. The Computer as a Log of Wood.

    Science.gov (United States)

    Coad, Peter; Coad, Raylene

    1985-01-01

    Because a teacher and a student were seated on either end of a log (facing each other), there was direct, eye-to-eye, one-on-one communication. If properly used, computers can take the place of the log, establishing the eye-to-eye, one-on-one, two-way communication. Advantages occur because computers are interactive, individualized, modular, and…

  17. Logging methods and peeling of Aspen

    Science.gov (United States)

    T. Schantz-Hansen

    1948-01-01

    The logging of forest products is influenced by many factors, including the size of the trees, density of the stand, the soundness of the trees, size of the area logged, topography and soil, weather conditions, the degree of utilization, the skill of the logger and the equipment used, the distance from market, etc. Each of these factors influences not only the method...

  18. Log-binomial models: exploring failed convergence.

    Science.gov (United States)

    Williamson, Tyler; Eliasziw, Misha; Fick, Gordon Hilton

    2013-12-13

    Relative risk is a summary metric that is commonly used in epidemiological investigations. Increasingly, epidemiologists are using log-binomial models to study the impact of a set of predictor variables on a single binary outcome, as they naturally offer relative risks. However, standard statistical software may report failed convergence when attempting to fit log-binomial models in certain settings. The methods that have been proposed in the literature for dealing with failed convergence use approximate solutions to avoid the issue. This research looks directly at the log-likelihood function for the simplest log-binomial model where failed convergence has been observed, a model with a single linear predictor with three levels. The possible causes of failed convergence are explored and potential solutions are presented for some cases. Among the principal causes is a failure of the fitting algorithm to converge despite the log-likelihood function having a single finite maximum. Despite these limitations, log-binomial models are a viable option for epidemiologists wishing to describe the relationship between a set of predictors and a binary outcome where relative risk is the desired summary measure. Epidemiologists are encouraged to continue to use log-binomial models and advocate for improvements to the fitting algorithms to promote the widespread use of log-binomial models.

  19. Aggregation of log-linear risks

    DEFF Research Database (Denmark)

    Embrechts, Paul; Hashorva, Enkeleijd; Mikosch, Thomas Valentin

    2014-01-01

    In this paper we work in the framework of a k-dimensional vector of log-linear risks. Under weak conditions on the marginal tails and the dependence structure of a vector of positive risks, we derive the asymptotic tail behaviour of the aggregated risk {and present} an application concerning log......-normal risks with {stochastic volatility....

  20. Palm distributions for log Gaussian Cox processes

    DEFF Research Database (Denmark)

    Coeurjolly, Jean-Francois; Møller, Jesper; Waagepetersen, Rasmus

    This paper reviews useful results related to Palm distributions of spatial point processes and provides a new result regarding the characterization of Palm distributions for the class of log Gaussian Cox processes. This result is used to study functional summary statistics for a log Gaussian Cox...

  1. Log canonical thresholds of smooth Fano threefolds

    International Nuclear Information System (INIS)

    Cheltsov, Ivan A; Shramov, Konstantin A

    2008-01-01

    The complex singularity exponent is a local invariant of a holomorphic function determined by the integrability of fractional powers of the function. The log canonical thresholds of effective Q-divisors on normal algebraic varieties are algebraic counterparts of complex singularity exponents. For a Fano variety, these invariants have global analogues. In the former case, it is the so-called α-invariant of Tian; in the latter case, it is the global log canonical threshold of the Fano variety, which is the infimum of log canonical thresholds of all effective Q-divisors numerically equivalent to the anticanonical divisor. An appendix to this paper contains a proof that the global log canonical threshold of a smooth Fano variety coincides with its α-invariant of Tian. The purpose of the paper is to compute the global log canonical thresholds of smooth Fano threefolds (altogether, there are 105 deformation families of such threefolds). The global log canonical thresholds are computed for every smooth threefold in 64 deformation families, and the global log canonical thresholds are computed for a general threefold in 20 deformation families. Some bounds for the global log canonical thresholds are computed for 14 deformation families. Appendix A is due to J.-P. Demailly.

  2. Data logging system upgrade for Indus accelerator

    International Nuclear Information System (INIS)

    Mishra, R.; Merh, B.N.; Agrawal, R.K.; Fatnani, P.; Navathe, C.P.; Pal, S.

    2012-01-01

    An accelerator has various subsystems like Magnet Power Supply, Beam Diagnostics and Vacuum etc. which are required to work in a stable manner to ensure required machine performance. Logging of system parameters at a faster rate plays a crucial role in analysing and understanding machine behaviour. Logging all the machine parameters consistently at the rate of typically more than 1 Hz has been the aim of a recent data logging system upgrade. Nearly ten thousand parameters are being logged at varying intervals of one second to one minute in Indus accelerator complex. The present logging scheme is augmented to log all these parameters at a rate equal to or more than 1 Hz. The database schema is designed according to the data type of the parameter. The data is distributed into historical table and intermediate table which comprises of recent data. Machine control applications read the parameter values from the control system and store them into the text files of finite time duration for each sub-system. The logging application of each sub-system passes these text files to database for bulk insertion. The detail design of database, logging scheme and its architecture is presented in the paper. (author)

  3. Processing of gamma-ray spectrometric logs

    International Nuclear Information System (INIS)

    Umiastowski, K.; Dumesnil, P.

    1984-10-01

    CEA (Commissariat a l'Energie Atomique) has developped a gamma-ray spectrometric tool, containing an analog-to-digital converter. This new tool permits to perform very precise uranium logs (natural gamma-ray spectrometry), neutron activation logs and litho-density logs (gamma-gamma spectrometric logs). Specific processing methods were developped to treate the particular problems of down-hole gamma-ray spectrometry. Extraction of the characteristic gamma-ray peak, even if they are superposed on the background radiation of very high intensity, is possible. This processing methode enables also to obtain geological informations contained in the continuous background of the spectrum. Computer programs are written in high level language for SIRIUS (VICTOR) and APOLLO computers. Exemples of uranium and neutron activation logs treatment are presented [fr

  4. Model wells for nuclear well logging

    International Nuclear Information System (INIS)

    Tittle, C.W.

    1989-01-01

    Considerations needed in the design and construction of model wells for nuclear log calibration are covered, with special attention to neutron porosity logging and total γ-ray logging. Pulsed neutron decay-time and spectral γ-ray logging are discussed briefly. The American Petroleum Institute calibration facility for nuclear logs is a good starting point for similar or expanded facilities. A few of its shortcomings are mentioned; they are minor. The problem of fluid saturation is emphasized. Attention is given to models made of consolidated rock and those containing unconsolidated material such as Ottawa sand. Needed precautions are listed. A similarity method is presented for estimating the porosity index of formations that are not fully saturated. (author)

  5. Density gamma gamma logging of oil wells

    International Nuclear Information System (INIS)

    Gulin, Yu.A.

    1974-01-01

    The application of gamma-gamma density logging for the evaluation of the volume weight and porosity of terrigenous and carbonate rocks in oil and gas boreholes is discussed. A two-probe (155 and 360 mm) apparatus has been developed for this purpose and has been in serial production since 1970. It is designed for use in boreholes between 190 and 300 mm in diameter and down to 4.000 metres deep at a maximum temperature of up to 120 deg C. The radiation source is 137 Cs with an activity of up to 100 kg-eq Ra. To interpret the results, measuring grids have been compiled in accordance with the experimental measurements taken on models of the strata. For carbonate sections combination of gamma-gamma density logging and epithermal-neutron-neutron logging is recommended. A combination of gamma-gamma density logging and neutron-gamma logging is used to evaluate the clayness of terrigenous deposits

  6. Logs of Paleoseismic Excavations Across the Central Range Fault, Trinidad

    Science.gov (United States)

    Crosby, Christopher J.; Prentice, Carol S.; Weber, John; Ragona, Daniel

    2009-01-01

    This publication makes available maps and trench logs associated with studies of the Central Range Fault, part of the South American-Caribbean plate boundary in Trinidad. Our studies were conducted in 2001 and 2002. We mapped geomorphic features indicative of active faulting along the right-lateral, Central Range Fault, part of the South American-Caribbean plate boundary in Trinidad. We excavated trenches at two sites, the Samlalsingh and Tabaquite sites. At the Samlalsingh site, sediments deposited after the most recent fault movement bury the fault, and the exact location of the fault was unknown until we exposed it in our excavations. At this site, we excavated a total of eleven trenches, six of which exposed the fault. The trenches exposed fluvial sediments deposited over a strath terrace developed on Miocene bedrock units. We cleaned the walls of the excavations, gridded the walls with either 1 m X 1 m or 1 m X 0.5 m nail and string grid, and logged the walls in detail at a scale of 1:20. Additionally, we described the different sedimentary units in the field, incorporating these descriptions into our trench logs. We mapped the locations of the trenches using a tape and compass. Our field logs were scanned, and unit contacts were traced in Adobe Illustrator. The final drafted logs of all the trenches are presented here, along with photographs showing important relations among faults and Holocene sedimentary deposits. Logs of south walls were reversed in Illustrator, so that all logs are drafted with the view direction to the north. We collected samples of various materials exposed in the trench walls, including charcoal samples for radiocarbon dating from both faulted and unfaulted deposits. The locations of all samples collected are shown on the logs. The ages of seventeen of the charcoal samples submitted for radiocarbon analysis at the University of Arizona Accelerator Mass Spectrometry Laboratory in Tucson, Ariz., are given in Table 1. Samples found in

  7. Designing and Piloting a Leadership Daily Practice Log: Using Logs to Study the Practice of Leadership

    Science.gov (United States)

    Spillane, James P.; Zuberi, Anita

    2009-01-01

    Purpose: This article aims to validate the Leadership Daily Practice (LDP) log, an instrument for conducting research on leadership in schools. Research Design: Using a combination of data sources--namely, a daily practice log, observations, and open-ended cognitive interviews--the authors evaluate the validity of the LDP log. Participants: Formal…

  8. LOG2MARKUP: State module to transform a Stata text log into a markup document

    DEFF Research Database (Denmark)

    2016-01-01

    log2markup extract parts of the text version from the Stata log command and transform the logfile into a markup based document with the same name, but with extension markup (or otherwise specified in option extension) instead of log. The author usually uses markdown for writing documents. However...

  9. Processing well logging data, for example for verification and calibration of well logs

    International Nuclear Information System (INIS)

    Suau, J.; Boutemy, Y.

    1981-01-01

    A method is described of machine processing well logging data derived from borehole exploring devices which investigate earth formations traversed by boreholes. The method can be used for verifying and recalibrating logs, reconstructing missing logs and combining the data to form a statistical model of the traversed earth formations. (U.K.)

  10. Gamma-ray analysis for U, TH and K on bulk cutting samples from deep wells in the Danish subbasin and the North German basin

    International Nuclear Information System (INIS)

    Leth Nielsen, B.; Loevborg, L.; Soerensen, P.; Mose, E.

    1987-04-01

    A total of 1329 bulk cutting samples from deep wells in Denmark were analysed for U, Th and K by laboratory gamma-ray analysis. Contamination of the samples by drilling mud additives, mud solids and fall down was studied by means of a wash down experiment and by comparison with the total gamma-ray response from wire-line logging. It is concluded that the inorganic geochemistry on bulk cutting samples must be applied with great caution. The data are useful for geochemical characterization of well sections and for regional geochemical correlation. Radioelement abundance logs and radioelement ratio logs are presented from 3 wells in the Danish Subbasin and 2 wells in the North German Basin. The radioelement geochemistry is discussed for the successive lithostratigraphical units and a reference radio element profile is established for the central part of the Danish Subbasin. Finally, a model describing the relationship between common lithofacies and their U content and Th/U ratio is suggested. The model deliniates the depositional environment and the relative distances to the provenance areas. It is concluded that 1) Uranium is mobile during deposition, but since then it is fixed by stable mineral phases at depth. 2) Thorium reflects source area characteristics and that any available ions are readily adsorped by clay minerals. Thorium anomalies may thus serve as lithostratigraphical markers. 3) Potassium occurs in unstable rock forming mineral phases. The present distribution is controlled not only by the clastic mineral assemblage, but also by the diagenetic processes through geologic time. 33 refs. (author)

  11. Application of oil-field well log interpretation techniques to the Cerro Prieto Geothermal Field

    Energy Technology Data Exchange (ETDEWEB)

    Ershaghi, I.; Phillips, L.B.; Dougherty, E.L.; Handy, L.L.

    1979-10-01

    An example is presented of the application of oil-field techniques to the Cerro Prieto Field, Mexico. The lithology in this field (sand-shale lithology) is relatively similar to oil-field systems. The study was undertaken as a part of the first series of case studies supported by the Geothermal Log Interpretation Program (GLIP) of the US Department of Energy. The suites of logs for individual wells were far from complete. This was partly because of adverse borehole conditions but mostly because of unavailability of high-temperature tools. The most complete set of logs was a combination of Dual Induction Laterolog, Compensated Formation Density Gamma Ray, Compensated Neutron Log, and Saraband. Temperature data about the wells were sketchy, and the logs had been run under pre-cooled mud condition. A system of interpretation consisting of a combination of graphic and numerical studies was used to study the logs. From graphical studies, evidence of hydrothermal alteration may be established from the trend analysis of SP (self potential) and ILD (deep induction log). Furthermore, the cross plot techniques using data from density and neutron logs may help in establishing compaction as well as rock density profile with depth. In the numerical method, R/sub wa/ values from three different resistivity logs were computed and brought into agreement. From this approach, values of formation temperature and mud filtrate resistivity effective at the time of logging were established.

  12. The gamma-ray full-spectrum logging represents the nuclear well logging trend

    International Nuclear Information System (INIS)

    Pang Jufeng

    1993-01-01

    The history of the nuclear well logging is briefly reviewed. It is discussed that the gamma-ray full-spectrum logging will be the developing trend of the nuclear well logging. Starting from the theory on the gamma-ray and neutron interactions with a geological formation, the discussion is based on the acquisitive capacity of the logging in formations, the ability to solve the problems about the formation evaluation and the geological interpretation in the petroleum prospecting, also the achieved technical level. The current status and the future developments of the γ-spectrum logging are discussed as well

  13. Logística del transporte

    OpenAIRE

    Robusté Antón, Francesc

    2005-01-01

    La logística se ha conformado como un proceso estratégico para organizar las actividades de producción y de distribución de las empresas. El concepto de sistema logístico ha incluido un amplio espectro de operaciones que condicionan la eficiencia y la competitividad empresarial en el actual contexto de globalización de la economía. En este sentido, este libro afronta y analiza los distintos aspectos que inciden en los procesos de planificación y gestión de los procesos logísticos relacionados...

  14. Supply of Rubber Wood Log in Malaysia

    OpenAIRE

    Noraida, A. W.; Abdul-Rahim, A. S.

    2014-01-01

    Issue on shortage of raw material for wood processing solved by discovery of rubber wood log as one of the substitutes the natural log. This paper examines the supply of rubber wood log in Malaysia. We employ ARDL Bound Approach Test and time series data from 1980 to 2010 which represented the whole Malaysia are used to achieve the established objectives. The result shown, in the long run harvested area and wages have 1% and 10% significant level respectively. While in the short run, there wa...

  15. Neutron logging reliability techniques and apparatus

    International Nuclear Information System (INIS)

    Johnstone, C.W.

    1975-01-01

    Apparatus and methods for verifying the validity of data derived at least in part by neutron logging of earth formations, and, where indicated, for affording neutron diffusion-corrected values of such data, are disclosed. (WHK)

  16. CMLOG: A common message logging system

    International Nuclear Information System (INIS)

    Chen, J.; Akers, W.; Bickley, M.; Wu, D.; Watson, W. III

    1997-01-01

    The Common Message Logging (CMLOG) system is an object-oriented and distributed system that not only allows applications and systems to log data (messages) of any type into a centralized database but also lets applications view incoming messages in real-time or retrieve stored data from the database according to selection rules. It consists of a concurrent Unix server that handles incoming logging or searching messages, a Motif browser that can view incoming messages in real-time or display stored data in the database, a client daemon that buffers and sends logging messages to the server, and libraries that can be used by applications to send data to or retrieve data from the database via the server. This paper presents the design and implementation of the CMLOG system meanwhile it will also address the issue of integration of CMLOG into existing control systems. CMLOG into existing control systems

  17. LATTE - Log and Time Tracking for Elections

    Data.gov (United States)

    Office of Personnel Management — LATTE - Log and Time Tracking for Elections is a time tracking and voucher preparation system used to schedule employees to cover elections, to document their time...

  18. Conversation Threads Hidden within Email Server Logs

    Science.gov (United States)

    Palus, Sebastian; Kazienko, Przemysław

    Email server logs contain records of all email Exchange through this server. Often we would like to analyze those emails not separately but in conversation thread, especially when we need to analyze social network extracted from those email logs. Unfortunately each mail is in different record and those record are not tided to each other in any obvious way. In this paper method for discussion threads extraction was proposed together with experiments on two different data sets - Enron and WrUT..

  19. Selective Logging, Fire, and Biomass in Amazonia

    Science.gov (United States)

    Houghton, R. A.

    1999-01-01

    Biomass and rates of disturbance are major factors in determining the net flux of carbon between terrestrial ecosystems and the atmosphere, and neither of them is well known for most of the earth's surface. Satellite data over large areas are beginning to be used systematically to measure rates of two of the most important types of disturbance, deforestation and reforestation, but these are not the only types of disturbance that affect carbon storage. Other examples include selective logging and fire. In northern mid-latitude forests, logging and subsequent regrowth of forests have, in recent decades, contributed more to the net flux of carbon between terrestrial ecosystems and the atmosphere than any other type of land use. In the tropics logging is also becoming increasingly important. According to the FAO/UNEP assessment of tropical forests, about 25% of total area of productive forests have been logged one or more times in the 60-80 years before 1980. The fraction must be considerably greater at present. Thus, deforestation by itself accounts for only a portion of the emissions carbon from land. Furthermore, as rates of deforestation become more accurately measured with satellites, uncertainty in biomass will become the major factor accounting for the remaining uncertainty in estimates of carbon flux. An approach is needed for determining the biomass of terrestrial ecosystems. 3 Selective logging is increasingly important in Amazonia, yet it has not been included in region-wide, satellite-based assessments of land-cover change, in part because it is not as striking as deforestation. Nevertheless, logging affects terrestrial carbon storage both directly and indirectly. Besides the losses of carbon directly associated with selective logging, logging also increases the likelihood of fire.

  20. Defect core detection in radiata pine logs

    International Nuclear Information System (INIS)

    Wallace, G.

    1993-01-01

    Internal defect cores in Pinus radiata logs arise primarily from the practice in New Zealand of pruning trees to increase the amount of clear wood. Realising the benefits of this practice when milling the logs is hampered by the lack of a practical method for detecting the defect cores. This report attempts to establish industry requirements for detections and examine techniques which may be suitable. Some trials of a novel technique are described. (author) 19 refs.; 11 figs

  1. Veneer recovery from Douglas-fir logs.

    Science.gov (United States)

    E.H. Clarke; A.C. Knauss

    1957-01-01

    During 1956, the Pacific Northwest Forest and Range Experiment Station made a series of six veneer-recovery studies in the Douglas-fir region of Oregon and Washington. The net volume of logs involved totaled approximately 777 M board-feet. Purpose of these studies was to determine volume recovery, by grade of veneer, from the four principal grades of Douglas-fir logs...

  2. Financial Indicators of Reduced Impact Logging Performance in Brazil: Case Study Comparisons

    Science.gov (United States)

    Thomas P. Holmes; Frederick Boltz; Douglas R. Carter

    2001-01-01

    Indicators of financial performance are compared for three case studies in the Brazilian Amazon. Each case study presents parameters obtained from monitoring initial harvest entries into primary forests for reduced impact logging (RIL) and conventional logging (CL) operations. Differences in cost definitions and data collection protocols complicate the analysis, and...

  3. Adjusting Quality index Log Values to Represent Local and Regional Commercial Sawlog Product Values

    Science.gov (United States)

    Orris D. McCauley; Joseph J. Mendel; Joseph J. Mendel

    1969-01-01

    The primary purpose of this paper is not only to report the results of a comparative analysis as to how well the Q.I. method predicts log product values when compared to commercial sawmill log output values, but also to develop a methodology which will facilitate the comparison and provide the adjustments needed by the sawmill operator.

  4. Nuclear logging and geothermal log interpretation: formation temperature sonde evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Ross, E.W.; Vagelatos, N.; Dickerson, J.M.; Nguyen, V.

    1982-01-01

    The theory and methodology of the neutron-based technique for the determination of the formation temperature in geothermal fields are discussed. The feasibility of the method was demonstrated before start of the present development phase. The present work is intended to evaluate the response of the temperature probe in a simulated fracture porosity granite matrix at temperatures likely to be encountered in known geothermal reservoirs. An above ground borehole model has been designed and constructed. The effect of high ambient temperatures on the response of the neutron detectors in the probe mockup used in the measurements was investigated and used to correct the detector counts. An improved data analysis method has been developed to account properly for the effects of low porosity and high temperatures. Measurements, using the above ground borehole model, have shown that a linear correlation between the ratio of thermal counts from a Gd-filtered detector to counts from a bare detector and formation temperature is good at temperatures as high as 380/sup 0/F. The present results are consistent with earlier data obtained in high-porosity laboratory models at lower temperatures (T < 167/sup 0/F). Further measurements at high temperature at various porosities and formation neutron absorption cross sections would be necessary for a more extensive comparison.

  5. Modeling Precipitation Extremes using Log-Histospline

    Science.gov (United States)

    Huang, W. K.; Nychka, D. W.; Zhang, H.

    2017-12-01

    One of the commonly used approaches to modeling univariate extremes is the peaks-overthreshold (POT) method. The POT method models exceedances over a (sufficiently high/low) threshold as a generalized Pareto distribution (GPD). To apply this method, a threshold has to be chosen and the estimates might be sensitive to the chosen threshold. Here we propose an alternative, the "Log-Histospline", to explore modeling the tail behavior and the remainder of the density in one step using the full range of the data. Log-Histospline applies a smoothing spline model on a finely binned histogram of the log transformed data to estimate its log density. By construction, we are able to preserve the polynomial upper tail behavior, a feature commonly observed in geophysical observations. The Log-Histospline can be extended to the spatial setting by treating the marginal (log) density at each location as spatially indexed functional data, and perform a dimension reduction and spatial smoothing. We illustrate the proposed method by analyzing precipitation data from regional climate model output (North American Regional Climate Change and Assessment Program (NARCCAP)).

  6. The evolution of the LEP logging database

    CERN Document Server

    Billen, R

    1995-01-01

    In January 1992, a project was started to create a system, using an on-line ORACLE database, to allow logging of a multitude of data on the Large Electron Positron Collider (LEP). The aim of this project was to log particle beam characteristics, physics parameters, hardware settings and environmental conditions. Storing and keeping track of this heterogeneous data for a period of at least one year would permit a better understanding of the behavior of the fairly new LEP Collider.After using the logging system for almost four years, nearly three years of which in full operation, the reliability and performance has been proved, endorsing the design of the database and surrounding software. Moreover, the large number of users of the logging database and the huge amount of new requests for data logging shows the high activity and usefulness of this system. Furthermore, in the context of the 1993 and 1995 energy scans, the logged data turns out to be indispensable for thorough monitoring of the LEP beam energy, wh...

  7. Hybrid Pre-Log and Post-Log Image Reconstruction for Computed Tomography.

    Science.gov (United States)

    Wang, Guobao; Zhou, Jian; Yu, Zhou; Wang, Wenli; Qi, Jinyi

    2017-12-01

    Tomographic image reconstruction for low-dose computed tomography (CT) is increasingly challenging as dose continues to reduce in clinical applications. Pre-log domain methods and post-log domain methods have been proposed individually and each method has its own disadvantage. While having the potential to improve image quality for low-dose data by using an accurate imaging model, pre-log domain methods suffer slow convergence in practice due to the nonlinear transformation from the image to measurements. In contrast, post-log domain methods have fast convergence speed but the resulting image quality is suboptimal for low dose CT data because the log transformation is extremely unreliable for low-count measurements and undefined for negative values. This paper proposes a hybrid method that integrates the pre-log model and post-log model together to overcome the disadvantages of individual pre-log and post-log methods. We divide a set of CT data into high-count and low-count regions. The post-log weighted least squares model is used for measurements in the high-count region and the pre-log shifted Poisson model for measurements in the low-count region. The hybrid likelihood function can be optimized using an existing iterative algorithm. Computer simulations and phantom experiments show that the proposed hybrid method can achieve faster early convergence than the pre-log shifted Poisson likelihood method and better signal-to-noise performance than the post-log weighted least squares method.

  8. Well log responses in metamorphic rocks near Maribor

    Directory of Open Access Journals (Sweden)

    1995-12-01

    Full Text Available In the Stražun forest at Pobrežje near Maribor, (Eastern Slovenia six boreholes have been drilled from 860 to 1600m deep. The paper describes geological conditions in mentioned boreholes, as well as in wider surroundings of Maribor with stress on metamorphic rocks. Based on pétrographie analysis of the rocks cuttings and well logs the upper phyllitic part ant the lower Pohorje series of themetamorphic complex could be separated. The first one includes phyllites with phyllitic quartzites and silicate marmorized limestones. The Pohorje series is represented by two-mica gneiss and schist, mainly with inclusions of amphibolite and eclogite, and subordinately retrograde chlorite-amphibole schist. The welllog responses for particular lithological sequences of metamorphic complex have been distinguished on the basis of conventional electrologs and gamma ray measurements.The problem of lithological interpretation of well logs in these rocks is described. Two fields of well log responses are distinguishable, as separated by the degree of natural radioactivity. Apart from veined quartzite, all rocks fromthe phyllitic part of the metamorphic complex are highly radioactive. In the Pohorje series gneiss, schist and diaphtorite-phyllonite are highly radioactive, while amphibolite, eclogite and retrograde chlorite-amphibole schist have low radioactivity.Finally, typical well log responses in lithological sequences of the discussed metamorphic rocks are presented.

  9. Design of a transport calculation system for logging sondes simulation

    International Nuclear Information System (INIS)

    Marquez Damian, Jose Ignacio

    2005-01-01

    Analysis of available resources in earth crust is performed by different techniques, one of them is neutron logging. Design of sondes that are used to make such logging is supported by laboratory experiments as well as by numerical calculations.This work presents several calculation schemes, designed to simplify the task of whom has to planify such experiments or optimize parameters of this kind of sondes.These schemes use transport calculation codes, especially DaRT, TORT and MCNP, and cross section processing modules from SCALE system.Additionally a system for DaRT and TORT data postprocessing using OpenDX is presented.It allows scalar flux spatial distribution analysis, as wells as cross section condensation and reaction rates calculation

  10. Integrating borehole logs and aquifer tests in aquifer characterization

    Science.gov (United States)

    Paillet, Frederick L.; Reese, R.S.

    2000-01-01

    Integration of lithologic logs, geophysical logs, and hydraulic tests is critical in characterizing heterogeneous aquifers. Typically only a limited number of aquifer tests can be performed, and these need to be designed to provide hydraulic properties for the principle aquifers in the system. This study describes the integration of logs and aquifer tests in the development of a hydrostratigraphic model for the surficial aquifer system in and around Big Cypress National Preserve in eastern Collier County, Florida. Borehole flowmeter tests provide qualitative permeability profiles in most of 26 boreholes drilled in the Study area. Flow logs indicate the depth of transmissive units, which are correlated across the study area. Comparison to published studies in adjacent areas indicates that the main limestone aquifer of the 000000Tamiami Formation in the study area corresponds with the gray limestone aquifer in western Dade County and the water table and lower Tamiami Aquifer in western Collier County. Four strategically located, multiwell aquifer tests are used to quantify the qualitative permeability profiles provided by the flowmeter log analysis. The hydrostratigraphic model based on these results defines the main aquifer in the central part of the study area as unconfined to semiconfined with a transmissivity as high as 30,000 m2/day. The aquifer decreases in transmissivity to less than 10,000 m2/day in some parts of western Collier County, and becomes confined to the east and northeast of the study area, where transmissivity decreases to below 5000 m2/day.Integration of lithologic logs, geophysical logs, and hydraulic tests is critical in characterizing heterogeneous aquifers. Typically only a limited number of aquifer tests can be performed, and these need to be designed to provide hydraulic properties for the principle aquifers in the system. This study describes the integration of logs and aquifer tests in the development of a hydrostratigraphic model for the

  11. Nuclear Well Log Properties of Natural Gas Hydrate Reservoirs

    Science.gov (United States)

    Burchwell, A.; Cook, A.

    2015-12-01

    Characterizing gas hydrate in a reservoir typically involves a full suite of geophysical well logs. The most common method involves using resistivity measurements to quantify the decrease in electrically conductive water when replaced with gas hydrate. Compressional velocity measurements are also used because the gas hydrate significantly strengthens the moduli of the sediment. At many gas hydrate sites, nuclear well logs, which include the photoelectric effect, formation sigma, carbon/oxygen ratio and neutron porosity, are also collected but often not used. In fact, the nuclear response of a gas hydrate reservoir is not known. In this research we will focus on the nuclear log response in gas hydrate reservoirs at the Mallik Field at the Mackenzie Delta, Northwest Territories, Canada, and the Gas Hydrate Joint Industry Project Leg 2 sites in the northern Gulf of Mexico. Nuclear logs may add increased robustness to the investigation into the properties of gas hydrates and some types of logs may offer an opportunity to distinguish between gas hydrate and permafrost. For example, a true formation sigma log measures the thermal neutron capture cross section of a formation and pore constituents; it is especially sensitive to hydrogen and chlorine in the pore space. Chlorine has a high absorption potential, and is used to determine the amount of saline water within pore spaces. Gas hydrate offers a difference in elemental composition compared to water-saturated intervals. Thus, in permafrost areas, the carbon/oxygen ratio may vary between gas hydrate and permafrost, due to the increase of carbon in gas hydrate accumulations. At the Mallik site, we observe a hydrate-bearing sand (1085-1107 m) above a water-bearing sand (1107-1140 m), which was confirmed through core samples and mud gas analysis. We observe a decrease in the photoelectric absorption of ~0.5 barnes/e-, as well as an increase in the formation sigma readings of ~5 capture units in the water-bearing sand as

  12. Political Unrest and Educational Electronic Resource Usage in a Conflict Zone, Kashmir (Indian Administered Kashmir: Log Analysis as Politico Analytical Tool=Hindistan Tarafından Yönetilen Keşmir Anlaşmazlık Bölgesi’nde Siyasi Karışıklık ve Eğitimle İlgili Elektronik Kaynakların Kullanımı: Siyasi Analiz Aracı Olarak Log Analizleri

    Directory of Open Access Journals (Sweden)

    Sumeer Gul

    2013-10-01

    Full Text Available Electronic resource usage has proved as one of the best decision making tools in the library setups. Electronic resource usage in relation to the political disturbance can act as one of the tools to highlight the impact of political disturbance on educational setups in general and the electronic resource usage in particular. The study takes a serious look in the electronic resource usage in Kashmir and the impact of unrest on it. The paper highlights a relational platform between education and conflict studies. How conflict affects the electronic resource usage in a conflict zone has been highlighted in the study. Transaction logs in the form of COUNTER Report deliberating the usage of Project Muse journal titles at University of Kashmir were analyzed to know the extent of usage of e-resources by the academia of Kashmir during the time of conflict from a time period of January 2008- December 2010. Peace has a great role to play in the development of any community from every aspect. Political disturbance hampers the educational sector to a greater extent. The usage logs helped to reveal the actual picture of academic behaviour of Kashmiris in the time of conflict. The study clearly reflects that political disturbance has a negative effect on the educational sphere in general and electronic resource usage in particular. The study was confined to the analysis of the transactions logs generated from Project Muse at University of Kashmir. The study can lay a base for the policy makers associated with education to take some immediate and curative steps that can control the devastating effects on the academia caused because of frequent disturbances in the valley of Kashmir. The study is an eye opener for the academicians and the policy makers in Kashmir. The study will be helpful in visualizing the utility of log analysis in reflecting the ill effects of political disturbance on academic circles. The paper is first of its kind trying to link education

  13. Well logging with natural gamma radiation

    International Nuclear Information System (INIS)

    Ellis, D.V.

    1983-01-01

    An invention is described for use in natural gamma radiation well logging in which measurements taken in a borehole are used in the search for valuable underground resources such as oil or gas. The invention comprises deriving a log of natural gamma radiation detected in selected energy windows for a selected borehole depth interval and converting it into a log of the selected subsurface materials, e.g. Th, U, K. This log is corrected for the effects of 1) either a gamma ray emitter in the borehole fluid, e.g. potassium salts and/or 2) a gamma ray attenuator in the borehole fluid, e.g. a strong attenuator such as barite and/or hematite. The Th, U, K log is particularly useful in the exploration of oil and gas resources since the Th, U, K concentrations are a good indication as to the presence, type and volume of shale and clay in the formations surrounding the borehole. (U.K.)

  14. Pulsed neutron logging - a modern approach to petroleum exploration

    International Nuclear Information System (INIS)

    Navalkar, M.P.

    1978-01-01

    As hydrocarbons have strikingly different properties for neutrons as compared with rocks, neutronic methods are useful to prepare logs of bore holes drilled for petroleum exploration. The earlier neutron logs were based on steady neutron sources, but the superior logs, namely, neutron life time log and neutron induced spectral log are based on pulsed neutron sources. The methods of obtaining these logs, their limitations and the field equipment required are described briefly. As the two logs are complementary, a plea has been made to develop field equipment which can obtain two logs in a single run. (M.G.B.)

  15. Perfil logístico de Colombia

    OpenAIRE

    Cardozo Maglioni, María Victoria; Lozano Suarez, María Goretty

    2012-01-01

    El presente documento ofrece un estudio del perfil logístico de Colombia con la finalidad de dar a conocer el estado de arte de las ciudades, puertos e infraestructura principal para facilitar la toma de decisiones de los empresarios. Para el desarrollo de este trabajo se determinaron a partir de un análisis competitivo del país; las principales ciudades y puertos; logrando establecer un inventario de maquinaria y equipo e infraestructura logística; enmarcados en retos ya establecidos en las ...

  16. Perfil logístico de Portugal

    OpenAIRE

    Rodríguez Páez, Johanna Marcela

    2014-01-01

    El presente documento ofrece un estudio del perfil logístico de Portugal, abarcando diferentes aspectos que afectan la competitividad y el desempeño de la cadena logística de un país, con la finalidad de conocer a uno de los socios comerciales con los cuáles Colombia se encuentra negociando, en este caso Portugal, uno de los 28 países que hace parte del reciente tratado de libre comercio aprobado con la Unión Europea, es preciso estudiar las ventajas competitivas que poseen dichos socios, a l...

  17. New portable neutron generator for well logging

    International Nuclear Information System (INIS)

    Chicanov, A.E.; Gromov, E. V.; Gulko, V. M.; Izmailov, A. V.

    1994-01-01

    The information about the design, investigation and testing of new well neutron generator for the pulse neutron logging (PNL) is given in this paper. The main physical characteristics of new PNL apparatus are: Neutron flux 2.10 sup 8 n/s ; Pulse frequency>=400 Hz; Diameter= 90 mm; Logging velocity >200 m/h; Number of probes = 2; Resource > 300 h. The generator were provided by gas-filled neutron accelerative tube named NTF-2. The perspective of application and optimization shown PNL apparatus are considered. (author)

  18. Well logging instrumental and methodological research

    International Nuclear Information System (INIS)

    Andrassy, L.; Barath, I.; Dorko, R.

    1983-01-01

    This part of the Annual Report of the Roland Eoetvoes Geophysical Institute (ELGI) of Hungary for 1982, summarizes the well logging instrumental and methodological researches of ELGI. The theoretical neutron diffusion fluxes for black and brown coals of Hungarian mines were calculated. A coal probe was developed and tested in boreholes using computerized data processing and interpretation. An X-ray radiometric method was used for the determination of Cu and Fe contents of minerals. Researches in the field of magnetic susceptibility and induced polarization logging are also summarized. A rapid analyzer for bauxite mining and a photorecorder for petroleum industry were developed by ELGI. (D.Gy.)

  19. Geophysical borehole logging test procedure: Final draft

    International Nuclear Information System (INIS)

    1986-09-01

    The purpose of geophysical borehole logging from the At-Depth Facility (ADF) is to provide information which will assist in characterizing the site geologic conditions and in classifying the engineering characteristics of the rock mass in the vicinity of the ADF. The direct goals of borehole logging include identification of lithologic units and their correlation from hole to hole, identification of fractured or otherwise porous or permeable zones, quantitative or semi-quantitative estimation of various formation properties, and evaluation of factors such as the borehole diameter and orientation. 11 figs., 4 tabs

  20. CS model coil experimental log book

    International Nuclear Information System (INIS)

    Nishijima, Gen; Sugimoto, Makoto; Nunoya, Yoshihiko; Wakabayashi, Hiroshi; Tsuji, Hiroshi

    2001-02-01

    Charging test of the ITER CS Model Coil which is the world's largest superconducting pulse coil and the CS Insert Coil had started at April 11, 2000 and had completed at August 18, 2000. In the campaign, total shot numbers were 356 and the size of the data file in the DAS (Data Acquisition System) was over 20 GB. This report is a database that consists of the log list and the log sheets of every shot. One can access the database, make a search, and browse results via Internet (http://1ogwww.naka.jaeri.go.jp). The database will be useful to quick search to choose necessary shots. (author)

  1. RAYSAW: a log sawing simulator for 3D laser-scanned hardwood logs

    Science.gov (United States)

    R. Edward. Thomas

    2013-01-01

    Laser scanning of hardwood logs provides detailed high-resolution imagery of log surfaces. Characteristics such as sweep, taper, and crook, as well as most surface defects, are visible to the eye in the scan data. In addition, models have been developed that predict interior knot size and position based on external defect information. Computerized processing of...

  2. Computer-based logging - simplifying station log preparation, access and use

    International Nuclear Information System (INIS)

    Davey, E.; Thompson, M.; Basso, R.; Herzog, K.; Lane, L.; Chatterton, R.

    1998-01-01

    A computer-based application for preparing and reviewing records of shift activities (i.e., logs) has been developed for CANDU station use. This application was developed with extensive participation of Operations staff at Darlington and several other CANDU stations, incorporates the lessons learned from previous station electronic logging experience, and was guided in development by the application of human engineering principles. Use of the application is expected to simplify and improve log preparation, search of log records, and more timely dissemination of log information to plant staff. This paper outlines the project rationale, reviews key development objectives for the application, discusses the development approach applied, describes key features of the application, and outlines the status of current work leading to station deployment. (author)

  3. Log-Gabor filters for image-based vehicle verification.

    Science.gov (United States)

    Arróspide, Jon; Salgado, Luis

    2013-06-01

    Vehicle detection based on image analysis has attracted increasing attention in recent years due to its low cost, flexibility, and potential toward collision avoidance. In particular, vehicle verification is especially challenging on account of the heterogeneity of vehicles in color, size, pose, etc. Image-based vehicle verification is usually addressed as a supervised classification problem. Specifically, descriptors using Gabor filters have been reported to show good performance in this task. However, Gabor functions have a number of drawbacks relating to their frequency response. The main contribution of this paper is the proposal and evaluation of a new descriptor based on the alternative family of log-Gabor functions for vehicle verification, as opposed to existing Gabor filter-based descriptors. These filters are theoretically superior to Gabor filters as they can better represent the frequency properties of natural images. As a second contribution, and in contrast to existing approaches, which transfer the standard configuration of filters used for other applications to the vehicle classification task, an in-depth analysis of the required filter configuration by both Gabor and log-Gabor descriptors for this particular application is performed for fair comparison. The extensive experiments conducted in this paper confirm that the proposed log-Gabor descriptor significantly outperforms the standard Gabor filter for image-based vehicle verification.

  4. Nonparametric Analyses of Log-Periodic Precursors to Financial Crashes

    Science.gov (United States)

    Zhou, Wei-Xing; Sornette, Didier

    We apply two nonparametric methods to further test the hypothesis that log-periodicity characterizes the detrended price trajectory of large financial indices prior to financial crashes or strong corrections. The term "parametric" refers here to the use of the log-periodic power law formula to fit the data; in contrast, "nonparametric" refers to the use of general tools such as Fourier transform, and in the present case the Hilbert transform and the so-called (H, q)-analysis. The analysis using the (H, q)-derivative is applied to seven time series ending with the October 1987 crash, the October 1997 correction and the April 2000 crash of the Dow Jones Industrial Average (DJIA), the Standard & Poor 500 and Nasdaq indices. The Hilbert transform is applied to two detrended price time series in terms of the ln(tc-t) variable, where tc is the time of the crash. Taking all results together, we find strong evidence for a universal fundamental log-frequency f=1.02±0.05 corresponding to the scaling ratio λ=2.67±0.12. These values are in very good agreement with those obtained in earlier works with different parametric techniques. This note is extracted from a long unpublished report with 58 figures available at , which extensively describes the evidence we have accumulated on these seven time series, in particular by presenting all relevant details so that the reader can judge for himself or herself the validity and robustness of the results.

  5. Reservoir evaluation of “T-X” field (Onshore, Niger delta) from well ...

    African Journals Online (AJOL)

    Wireline log analysis was employed in the characterization of the reservoirs in the well studied; the hydrocarbon sands were delineated by the use of gamma ray, resistivity and density/neutron from which the reservoir quality were determined. Fluid types defined in the reservoirs on the basis of neutron/density log ...

  6. Deep Borehole Emplacement Mode Hazard Analysis Revision 0

    Energy Technology Data Exchange (ETDEWEB)

    Sevougian, S. David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-08-07

    This letter report outlines a methodology and provides resource information for the Deep Borehole Emplacement Mode Hazard Analysis (DBEMHA). The main purpose is identify the accident hazards and accident event sequences associated with the two emplacement mode options (wireline or drillstring), to outline a methodology for computing accident probabilities and frequencies, and to point to available databases on the nature and frequency of accidents typically associated with standard borehole drilling and nuclear handling operations. Risk mitigation and prevention measures, which have been incorporated into the two emplacement designs (see Cochran and Hardin 2015), are also discussed. A key intent of this report is to provide background information to brief subject matter experts involved in the Emplacement Mode Design Study. [Note: Revision 0 of this report is concentrated more on the wireline emplacement mode. It is expected that Revision 1 will contain further development of the preliminary fault and event trees for the drill string emplacement mode.

  7. Potential for shared log transport services

    Science.gov (United States)

    Tim McDonald; Steve Taylor; Jorge Valenzuela

    2001-01-01

    A simulation model of a log transport logistics network was developed. The model could be structured to either share truck capacity among a group of loggers, or to assign a fixed number of trucks to individual loggers. Another variation of the model allowed the use of a staging yard to set out loaded trailers and deliver them to destinations using dedicated shuttle...

  8. Log Gaussian Cox processes on the sphere

    DEFF Research Database (Denmark)

    Pacheco, Francisco Andrés Cuevas; Møller, Jesper

    We define and study the existence of log Gaussian Cox processes (LGCPs) for the description of inhomogeneous and aggregated/clustered point patterns on the d-dimensional sphere, with d = 2 of primary interest. Useful theoretical properties of LGCPs are studied and applied for the description of sky...

  9. Analyzing Grid Log Data with Affinity Propagation

    NARCIS (Netherlands)

    Modena, G.; van Someren, M.W.; Ali, M; Bosse, T.; Hindriks, K.V.; Hoogendoorn, M.; Jonker, C.M; Treur, J.

    2013-01-01

    In this paper we present an unsupervised learning approach to detect meaningful job traffic patterns in Grid log data. Manual anomaly detection on modern Grid environments is troublesome given their increasing complexity, the distributed, dynamic topology of the network and heterogeneity of the jobs

  10. 29 CFR 1910.266 - Logging operations.

    Science.gov (United States)

    2010-07-01

    ... harvesting and the logging of sawlogs, veneer bolts, poles, pilings and other forest products. This standard... portion thereof. Spring pole. A tree, segment of a tree, limb, or sapling which is under stress or tension... shall be avoided. (iv) When a spring pole or other tree under stress is cut, no employee other than the...

  11. ADN* Density log estimation Using Rockcell*

    International Nuclear Information System (INIS)

    Okuku, C.; Iloghalu, Emeka. M.; Omotayo, O.

    2003-01-01

    This work is intended to inform on the possibilities of estimating good density data in zones associated with sliding in a reservoir with ADN* tool with or without ADOS in string in cases where repeat sections were not done, possibly due to hole stability or directional concerns. This procedure has been equally used to obtain a better density data in corkscrew holes. Density data (ROBB) was recomputed using neural network in RockCell* to estimate the density over zones of interest. RockCell* is a Schlumberger software that has neural network functionally which can be used to estimate missing logs using the combination of the responses of other log curves and intervals that are not affected by sliding. In this work, an interval was selected and within this interval twelve litho zones were defined using the unsupervised neural network. From this a training set was selected based on intervals of very good log responses outside the sliding zones. This training set was used to train and run the neural network for a specific lithostratigraphic interval. The results matched the known good density curve. Then after this, an estimation of the density curve was done using the supervised neural network. The output from this estimation matched very closely in the good portions of the log, thus providing some density measurements in the sliding zone. This methodology provides a scientific solution to missing data during the process of Formation evaluation

  12. Changes in the Logging Labor Force

    Science.gov (United States)

    Charles H. Wolf; Jean W. Nolley

    1977-01-01

    Employment in the logging industry dropped 28 percent between 1950 and 1970, while output of industrial roundwood increased 31 percent. Today's loggers are older, better educated, and more skilled. A large proportion are self-employed, many work less than a full year, and a substantial number have incomes below the poverty level. Mechanization of timber harvesting...

  13. Alaska midgrade logs: supply and offshore demand.

    Science.gov (United States)

    Donald F. Flora; Wendy J. McGinnis

    1989-01-01

    The outlook for shipments and prices of export logs from Alaska differs significantly by grade (quality class). For the majority lying in the middle of the value range, the trend of prices is projected to increase $200 per thousand board feet, or about 55 percent, by 2000. Shipments are expected to rise about 30 percent by 1995 and then subside about 10 percent. These...

  14. Apache Flume distributed log collection for Hadoop

    CERN Document Server

    D'Souza, Subas

    2013-01-01

    A starter guide that covers Apache Flume in detail.Apache Flume: Distributed Log Collection for Hadoop is intended for people who are responsible for moving datasets into Hadoop in a timely and reliable manner like software engineers, database administrators, and data warehouse administrators

  15. Modelling tropical forests response to logging

    Science.gov (United States)

    Cazzolla Gatti, Roberto; Di Paola, Arianna; Valentini, Riccardo; Paparella, Francesco

    2013-04-01

    Tropical rainforests are among the most threatened ecosystems by large-scale fragmentation due to human activity such as heavy logging and agricultural clearance. Although, they provide crucial ecosystem goods and services, such as sequestering carbon from the atmosphere, protecting watersheds and conserving biodiversity. In several countries forest resource extraction has experienced a shift from clearcutting to selective logging to maintain a significant forest cover and understock of living biomass. However the knowledge on the short and long-term effects of removing selected species in tropical rainforest are scarce and need to be further investigated. One of the main effects of selective logging on forest dynamics seems to be the local disturbance which involve the invasion of open space by weed, vines and climbers at the expense of the late-successional state cenosis. We present a simple deterministic model that describes the dynamics of tropical rainforest subject to selective logging to understand how and why weeds displace native species. We argue that the selective removal of tallest tropical trees carries out gaps of light that allow weeds, vines and climbers to prevail on native species, inhibiting the possibility of recovery of the original vegetation. Our results show that different regime shifts may occur depending on the type of forest management adopted. This hypothesis is supported by a dataset of trees height and weed/vines cover that we collected from 9 plots located in Central and West Africa both in untouched and managed areas.

  16. Exploration and grade control neutron logging

    International Nuclear Information System (INIS)

    Eisler, P.L.

    1982-01-01

    Techniques used in neutron logging in boreholes are discussed. They include the application of neutron probes to porosity measurements, to lithological determinations based on macroscopic cross-section measurements and measurements of the concentration of chemical constituents in rocks and ores

  17. Stream macroinvertebrate response to clearcut logging

    Science.gov (United States)

    J. Bruce Wallace; Damon. Ely

    2014-01-01

    Why study response of stream invertebrates to watershed disturbances such as clearcut logging? Stream invertebrates can be excellent integrators of changes in such ecosystem phenomena as changes in the food base of ecosystems. For example, a number of invertebrate taxa appear to track changes in food resources. Many taxa also exhibit substrate-specific as well as taxon...

  18. Bi-log-concave Distribution Functions

    DEFF Research Database (Denmark)

    Dümbgen, Lutz; Kolesnyk, Petro; Wilke, Ralf

    2017-01-01

    Nonparametric statistics for distribution functions F or densities f=F′ under qualitative shape constraints constitutes an interesting alternative to classical parametric or entirely nonparametric approaches. We contribute to this area by considering a new shape constraint: F is said to be bi-log...

  19. 29 CFR 1918.88 - Log operations.

    Science.gov (United States)

    2010-07-01

    ... Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Handling Cargo § 1918.88 Log operations. (a) Working in... protected by a personal flotation device meeting the requirements of § 1918.105(b)(2). (c) Footwear. The...

  20. Critical care procedure logging using handheld computers.

    Science.gov (United States)

    Martinez-Motta, J Carlos; Walker, Robin; Stewart, Thomas E; Granton, John; Abrahamson, Simon; Lapinsky, Stephen E

    2004-10-01

    We conducted this study to evaluate the feasibility of implementing an internet-linked handheld computer procedure logging system in a critical care training program. Subspecialty trainees in the Interdepartmental Division of Critical Care at the University of Toronto received and were trained in the use of Palm handheld computers loaded with a customized program for logging critical care procedures. The procedures were entered into the handheld device using checkboxes and drop-down lists, and data were uploaded to a central database via the internet. To evaluate the feasibility of this system, we tracked the utilization of this data collection system. Benefits and disadvantages were assessed through surveys. All 11 trainees successfully uploaded data to the central database, but only six (55%) continued to upload data on a regular basis. The most common reason cited for not using the system pertained to initial technical problems with data uploading. From 1 July 2002 to 30 June 2003, a total of 914 procedures were logged. Significant variability was noted in the number of procedures logged by individual trainees (range 13-242). The database generated by regular users provided potentially useful information to the training program director regarding the scope and location of procedural training among the different rotations and hospitals. A handheld computer procedure logging system can be effectively used in a critical care training program. However, user acceptance was not uniform, and continued training and support are required to increase user acceptance. Such a procedure database may provide valuable information that may be used to optimize trainees' educational experience and to document clinical training experience for licensing and accreditation.

  1. Accurate and log g of δ Sct stars using Asteroseismology

    Science.gov (United States)

    Antonio, García Hernández; Monteiro, Mário J. P. F. G.; Guo, Zhao; Reese, Daniel R.; Suárez, Juan Carlos; Martín, Susana; Pascual-Granado, Javier; Moya, Andrés; Garrido, Rafael

    2017-10-01

    In this work, we present a new method to determine the surface gravity of δ Sct stars. We used a refined relation and the stellar parallaxes or luminosities to determine their masses and radii. A comparison with the data obtained from the binary analysis, has shown that the values found by both methods are equivalent, within the uncertainties. Moreover, thanks to the refined relation, the uncertainties in log g are of the order of those usually estimated with high-resolution spectroscopy. Because of that, this new method to determine the surface gravity is an important step forward to break the degeneracy problem in the spectroscopic analysis.

  2. Log-Determinant Divergences Revisited: Alpha-Beta and Gamma Log-Det Divergences

    Directory of Open Access Journals (Sweden)

    Andrzej Cichocki

    2015-05-01

    Full Text Available This work reviews and extends a family of log-determinant (log-det divergences for symmetric positive definite (SPD matrices and discusses their fundamental properties. We show how to use parameterized Alpha-Beta (AB and Gamma log-det divergences to generate many well-known divergences; in particular, we consider the Stein’s loss, the S-divergence, also called Jensen-Bregman LogDet (JBLD divergence, Logdet Zero (Bhattacharyya divergence, Affine Invariant Riemannian Metric (AIRM, and other divergences. Moreover, we establish links and correspondences between log-det divergences and visualise them on an alpha-beta plane for various sets of parameters. We use this unifying framework to interpret and extend existing similarity measures for semidefinite covariance matrices in finite-dimensional Reproducing Kernel Hilbert Spaces (RKHS. This paper also shows how the Alpha-Beta family of log-det divergences relates to the divergences of multivariate and multilinear normal distributions. Closed form formulas are derived for Gamma divergences of two multivariate Gaussian densities; the special cases of the Kullback-Leibler, Bhattacharyya, Rényi, and Cauchy-Schwartz divergences are discussed. Symmetrized versions of log-det divergences are also considered and briefly reviewed. Finally, a class of divergences is extended to multiway divergences for separable covariance (or precision matrices.

  3. Tradeoffs and interdependence in the Alaska cant and log markets.

    Science.gov (United States)

    Donald Flora; Una Woller; Michael. Neergaard

    1990-01-01

    During the 1980s, log exports from Alaska have risen while cant (lumber) exports have declined. Eight explanations for the difference between cant and log market behavior are explored. It seems that declining demand for wood products in Japan and a surge of private-sector log harvests in Alaska are enough to account for the apparent substitution of logs for cants. It...

  4. Anomalous self potential (sp) log signatures observed in a water ...

    African Journals Online (AJOL)

    Geophysical logging was done after drilling had been completed in a water well at Okwudor, South Eastern Nigeria. Three electric logs were run viz: Self Potential (SP), Resistivity N16″ and N64″ logs. An anomaly was observed in the SP log. The SP results from this well show some deviation from the standard norm.

  5. Veneer Log Production and Receipts in the Southeast, 1969

    Science.gov (United States)

    Richard L. Welch

    1971-01-01

    In 1969, production of veneer logs was almost 657 million board feet in the Southeast, while receipts of domestic logs at the 136 mills in the area were over 690 million board feet. Pine log production now amounts to 40 percent of the total, while hardwood log production is down 17 percent from that of 1963.

  6. Logging utilization in Idaho: Current and past trends

    Science.gov (United States)

    Eric A. Simmons; Todd A. Morgan; Erik C. Berg; Stanley J. Zarnoch; Steven W. Hayes; Mike T. Thompson

    2014-01-01

    A study of commercial timber-harvesting activities in Idaho was conducted during 2008 and 2011 to characterize current tree utilization, logging operations, and changes from previous Idaho logging utilization studies. A two-stage simple random sampling design was used to select sites and felled trees for measurement within active logging sites. Thirty-three logging...

  7. Analysis of event logs from syringe pumps: a retrospective pilot study to assess possible effects of syringe pumps on safety in a university hospital critical care unit in Germany.

    Science.gov (United States)

    Kastrup, Marc; Balzer, Felix; Volk, Thomas; Spies, Claudia

    2012-07-01

    Medication errors occur in approximately one out of five doses in a typical hospital setting. Patients in the intensive care unit (ICU) are particularly susceptible to errors during the application of intravenous drugs as they receive numerous potent drugs applied by syringe pumps. The aim of this study was to analyse the effects on potential harmful medication errors and to address factors that have potential for improving medication safety after the introduction of a standardized drug library into syringe pumps with integrated decision support systems. A team of physicians and nurses developed a dataset that defined standardized drug concentrations, application rates and alert limits to prevent accidental overdosing of intravenous medications. This dataset was implemented in 100 syringe pumps with the ability to log programming errors, alerts, reprogramming events and overrides ('smart pumps'). In this retrospective pilot study, all pump-related transaction data were obtained from the pump logs, by downloading the data from the pumps, covering 20 months of use between 1 April 2008 and 30 November 2009. Patient data were gathered from the electronic patient charts. The study was performed in a cardiothoracic ICU of the Charité University Hospital, Berlin, Germany. A total of 7884 patient treatment days and 133,601 infusion starts were evaluated. The drug library with the features of the dose rate was used in 92.8% of the syringe pump starts, in 1.5% of the starts a manual dosing mode without the use of the drug library was used and in 5.7% of the starts the mode 'mL/h', without any calculation features, was used. The most frequently used drugs were vasoactive drugs, followed by sedation medication. The user was alerted for a potentially harmful overdosing in 717 cases and in 66 cases the pumps were reprogrammed after the alert. During the early morning hours a higher rate of alarms was generated by the pumps, compared with the rest of the day. Syringe pumps with

  8. Spectrum Gamma Ray bore hole logging while tripping with the sea floor drill rig MARUM-MeBo

    Science.gov (United States)

    Freudenthal, Tim; Steinke, Stephan; Mohtadi, Mahyar; Hebbeln, Dierk; Wefer, Gerold

    2013-04-01

    The robotic Sea Floor Drill Rig MARUM-MeBo developed at the MARUM Center for Marine Environmental Sciences at the University of Bremen was used to retrieve long sediment cores at two sites in the northern South China Sea. Both sites are located in about 1000 m water depth in southeasterly and southwesterly direction of the Pearl River mouth, respectively. South East Asian Monsoon variability controls terrigenous material transport by rivers into the South China Sea. The Pearl River is one of the largest rivers of the region that discharges into the northern South China Sea. The terrigenous fraction of marine sediments of the northern South China Sea therefore provides an excellent archive for reconstructing past variability of the South East Asian Monsoon system. In analogy to the drilling strategy within the Integrated Ocean Drilling Program IODP multiple holes were drilled in order to generate continuous spliced records at both sites. Overall the MARUM-MeBo drilled 374 m during 5 deployments with a maximum drilling depth of 80.85 m and an average core recovery of 94 %. Here we present first results of bore hole logging conducted during 4 of the 5 deployments with a spectrum gamma ray (SGR) probe adapted for the use with MARUM-MeBo. This probe is an autonomous slim hole probe that is used in the logging while tripping mode. This method is especially favorable for remote controlled drilling and logging operation. The probe is equipped with its own energy source and data storage. The probe is lowered into the drill string after the target wire-line coring depth is reached and after the last inner core barrel has been retrieved. When the probe has landed on the shoulder ring at the bottom of the hole, the drill string is pulled out and disassembled. The probe, while being raised with the drill string, continuously measures the geophysical properties of the in situ sediments and rocks. Since the bore hole is stabilized during the tripping process by the drill string

  9. Limitations and developing directions of pulsed neutron logging

    International Nuclear Information System (INIS)

    Wu Wensheng; Xiao Lizhi

    2007-01-01

    The paper explains briefly the principle of pulsed neutron logging method, summarizes the system and uses of the method in petroleum logging. The paper points out the limitations of pulsed neutron logging such as low precise measurements, low logging speed, plenty of influence factors, low vertical resolution, bad adaptability, difficult logging interpretation and so on, and expounds its developing directions in hardware, software, method and principle. (authors)

  10. A risk index for multicriterial selection of a logging system with low environmental impact

    International Nuclear Information System (INIS)

    Horodnic, Sergiu Andrei

    2015-01-01

    Setting up the working stages in forest operations is conditioned by environmental protection and forest health requirements. This paper exposes a method for improving the decision-making process by choosing the most environmentally effective logging systems according to terrain configuration and stand characteristics. Such a methodology for selecting machines or logging systems accounting for environment, safety as well as economics, becomes mandatory in the context of sustainable management of forest with multiple functions. Based on analytic hierarchy process analysis the following classification of the environmental performance for four considered alternatives was obtained: skyline system (42.43%), forwarder system (20.22%), skidder system (19.92%) and horse logging system (17.43%). Further, an environmental risk matrix for the most important 28 risk factors specific to any work equipment used in forest operations was produced. In the end, a multicriterial analysis generated a risk index RI ranging between 1.0 and 3.5, which could help choosing the optimal combination of logging system and logging equipment with low environmental impact. In order to demonstrate the usefulness of the proposed approach, a simple application in specific conditions of a harvesting site is presented. - Highlights: • We propose a decision-making algorithm to select eco-friendly logging systems. • Analytic hierarchy process was applied for ranking 4 types of logging systems. • An environmental risk matrix with 28 risk factors in forest operations was made up

  11. Log-cubic method for generation of soil particle size distribution curve.

    Science.gov (United States)

    Shang, Songhao

    2013-01-01

    Particle size distribution (PSD) is a fundamental physical property of soils. Traditionally, the PSD curve was generated by hand from limited data of particle size analysis, which is subjective and may lead to significant uncertainty in the freehand PSD curve and graphically estimated cumulative particle percentages. To overcome these problems, a log-cubic method was proposed for the generation of PSD curve based on a monotone piecewise cubic interpolation method. The log-cubic method and commonly used log-linear and log-spline methods were evaluated by the leave-one-out cross-validation method for 394 soil samples extracted from UNSODA database. Mean error and root mean square error of the cross-validation show that the log-cubic method outperforms two other methods. What is more important, PSD curve generated by the log-cubic method meets essential requirements of a PSD curve, that is, passing through all measured data and being both smooth and monotone. The proposed log-cubic method provides an objective and reliable way to generate a PSD curve from limited soil particle analysis data. This method and the generated PSD curve can be used in the conversion of different soil texture schemes, assessment of grading pattern, and estimation of soil hydraulic parameters and erodibility factor.

  12. A risk index for multicriterial selection of a logging system with low environmental impact

    Energy Technology Data Exchange (ETDEWEB)

    Horodnic, Sergiu Andrei, E-mail: horodnic@usv.ro

    2015-02-15

    Setting up the working stages in forest operations is conditioned by environmental protection and forest health requirements. This paper exposes a method for improving the decision-making process by choosing the most environmentally effective logging systems according to terrain configuration and stand characteristics. Such a methodology for selecting machines or logging systems accounting for environment, safety as well as economics, becomes mandatory in the context of sustainable management of forest with multiple functions. Based on analytic hierarchy process analysis the following classification of the environmental performance for four considered alternatives was obtained: skyline system (42.43%), forwarder system (20.22%), skidder system (19.92%) and horse logging system (17.43%). Further, an environmental risk matrix for the most important 28 risk factors specific to any work equipment used in forest operations was produced. In the end, a multicriterial analysis generated a risk index RI ranging between 1.0 and 3.5, which could help choosing the optimal combination of logging system and logging equipment with low environmental impact. In order to demonstrate the usefulness of the proposed approach, a simple application in specific conditions of a harvesting site is presented. - Highlights: • We propose a decision-making algorithm to select eco-friendly logging systems. • Analytic hierarchy process was applied for ranking 4 types of logging systems. • An environmental risk matrix with 28 risk factors in forest operations was made up.

  13. Three looks at users: a comparison of methods for studying digital library use. User studies, Digital libraries, Digital music libraries, Music, Information use, Information science, Contextual inquiry, Contextual design, User research, Questionnaires, Log file analysis

    Directory of Open Access Journals (Sweden)

    Mark Notess

    2004-01-01

    Full Text Available Compares three user research methods of studying real-world digital library usage within the context of the Variations and Variations2 digital music libraries at Indiana University. After a brief description of both digital libraries, each method is described and illustrated with findings from the studies. User satisfaction questionnaires were used in two studies, one of Variations (n=30 and the other of Variations2 (n=12. Second, session activity log files were examined for 175 Variations2 sessions using both quantitative and qualitative methods. The third method, contextual inquiry, is illustrated with results from field observations of four voice students' information usage patterns. The three methods are compared in terms of expertise required; time required to set up, conduct, and analyse resulting data; and the benefits derived. Further benefits are achieved with a mixed-methods approach, combining the strengths of the methods to answer questions lingering as a result of other methods.

  14. Assessment of radiation safety in well logging

    International Nuclear Information System (INIS)

    Alles, A.; Pérez, Y.; Duménigo, C.

    2015-01-01

    Radiation safety assessments required by current regulations are a means to verify compliance with the requirements. Different methods have been used for this purpose. In the paper the results of applying the method of risk matrices, applied for the first time in the practice of well logging are exposed. For each initiating event frequency of occurrence, the severity of its consequences and the probability of failure of the barriers identified were evaluated. Starting from these assumptions, the risk associated is determined for each of the identified accident sequences, using for this the SEVRRA code 'Risk Assessment System', originally designed for use in radiotherapy. As an result sequences increased risk associated with the practice of well logging were identified, which is the starting point for the further implementation of a coherent program of dose optimization in practice. [es

  15. CS model coil experimental log book

    Energy Technology Data Exchange (ETDEWEB)

    Nishijima, Gen; Sugimoto, Makoto; Nunoya, Yoshihiko; Wakabayashi, Hiroshi; Tsuji, Hiroshi [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    2001-02-01

    Charging test of the ITER CS Model Coil which is the world's largest superconducting pulse coil and the CS Insert Coil had started at April 11, 2000 and had completed at August 18, 2000. In the campaign, total shot numbers were 356 and the size of the data file in the DAS (Data Acquisition System) was over 20 GB. This report is a database that consists of the log list and the log sheets of every shot. One can access the database, make a search, and browse results via Internet (http://1ogwww.naka.jaeri.go.jp). The database will be useful to quick search to choose necessary shots. (author)

  16. High resolution gamma spectroscopy well logging system

    International Nuclear Information System (INIS)

    Giles, J.R.; Dooley, K.J.

    1997-01-01

    A Gamma Spectroscopy Logging System (GSLS) has been developed to study sub-surface radionuclide contamination. The absolute counting efficiencies of the GSLS detectors were determined using cylindrical reference sources. More complex borehole geometries were modeled using commercially available shielding software and correction factors were developed based on relative gamma-ray fluence rates. Examination of varying porosity and moisture content showed that as porosity increases, and as the formation saturation ratio decreases, relative gamma-ray fluence rates increase linearly for all energies. Correction factors for iron and water cylindrical shields were found to agree well with correction factors determined during previous studies allowing for the development of correction factors for type-304 stainless steel and low-carbon steel casings. Regression analyses of correction factor data produced equations for determining correction factors applicable to spectral gamma-ray well logs acquired under non-standard borehole conditions

  17. Reconciling timber extraction with biodiversity conservation in tropical forests using reduced-impact logging

    Science.gov (United States)

    Bicknell, Jake E; Struebig, Matthew J; Davies, Zoe G; Baraloto, Christopher

    2015-01-01

    Over 20% of the world's tropical forests have been selectively logged, and large expanses are allocated for future timber extraction. Reduced-impact logging (RIL) is being promoted as best practice forestry that increases sustainability and lowers CO2 emissions from logging, by reducing collateral damage associated with timber extraction. RIL is also expected to minimize the impacts of selective logging on biodiversity, although this is yet to be thoroughly tested. We undertake the most comprehensive study to date to investigate the biodiversity impacts of RIL across multiple taxonomic groups. We quantified birds, bats and large mammal assemblage structures, using a before-after control-impact (BACI) design across 20 sample sites over a 5-year period. Faunal surveys utilized point counts, mist nets and line transects and yielded >250 species. We examined assemblage responses to logging, as well as partitions of feeding guild and strata (understorey vs. canopy), and then tested for relationships with logging intensity to assess the primary determinants of community composition. Community analysis revealed little effect of RIL on overall assemblages, as structure and composition were similar before and after logging, and between logging and control sites. Variation in bird assemblages was explained by natural rates of change over time, and not logging intensity. However, when partitioned by feeding guild and strata, the frugivorous and canopy bird ensembles changed as a result of RIL, although the latter was also associated with change over time. Bats exhibited variable changes post-logging that were not related to logging, whereas large mammals showed no change at all. Indicator species analysis and correlations with logging intensities revealed that some species exhibited idiosyncratic responses to RIL, whilst abundance change of most others was associated with time. Synthesis and applications. Our study demonstrates the relatively benign effect of reduced

  18. Nuclear well logging process and device

    International Nuclear Information System (INIS)

    Antkiw, Stephen; Murphy, R.D.

    1976-01-01

    The invention concerns a nuclear logging process and system specially designed for tubed probes and making it possible to obtain additional data on the location and yield of oil bearing strata. The invention coordinates the study of a neutron characteristic with that of gamma ray spectroscopy to obtain, with a single apparatus, enough information on the various parameters concerning strata enabling a complete and accurate assessment to be made of the oil bearing areas [fr

  19. Ceramic vacuum tubes for geothermal well logging

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, R.D.

    1977-01-01

    Useful design data acquired in the evaluation of ceramic vacuum tubes for the development of a 500/sup 0/C instrumentation amplifier are presented. The general requirements for ceramic vacuum tubes are discussed for application to the development of high temperature well logs. Commercially available tubes are described and future contract activities that specifically relate to ceramic vacuum tubes are detailed. Supplemental data are presented in the appendix.

  20. Unification of acoustic drillhole logging data

    International Nuclear Information System (INIS)

    Oehman, I.; Palmen, J.; Heikkinen, E.

    2009-04-01

    Posiva Oy prepares for disposal of spent nuclear fuel in bedrock in Olkiluoto, Eurajoki. This is in accordance of the application filed in 1999, the Decision-in-Principle of the State Council in 2000, and ratification by the Parliament in 2001. The site characterization at Olkiluoto has included comprehensive geological, hydrological, geochemical and geophysical investigations airborne, on ground and in drillholes since 1988. One of key techniques in geophysical drillhole surveys has been acoustic full waveform logging, which has been implemented since 1994. Various tools have been used in acquisition of acoustic data and several processing techniques have been applied. The logging work and processing to P and S wave velocities has been previously carried out on single drillhole basis. Comparisons to actual values and levels have not been made, and the results have not been calibrated. Therefore results for different drillholes have not been comparable. Resolution of the P and S wave velocity has been rather coarse, and depth correlation to the core data has been on tentative level. As the investigation data has been accumulating, it has become possible to correlate the results to geological and laboratory control data and to calibrate the results of separate measurement campaigns and different drillholes together onto same reference level and resolution. The presented technique has been applied for drillhole OL-KR29 onwards and has set the processing standard, settings and reference levels for later surveys. This approach will further assist the application of the method for mapping and numerical description of lithology variation and possible effect of alteration and deformation on it. Further on, the P and S wave velocity data together with density can be used in computing of dynamic in situ rock mechanical parameters, and possibly in correlating rock strength laboratory data to P and S wave velocity logging data. The acoustic logging data from drillholes OL-KR1

  1. Detection of unexploded ordnance by PGNAA based borehole-logging

    International Nuclear Information System (INIS)

    John Kettler; RWTH-Aachen University, Aachen; Eric Mauerhofer; Marco Steinbusch

    2013-01-01

    The performance of a borehole-logging system, based on prompt-gamma-neutron-activation-analysis (PGNAA), for explosive detection was studied by Monte-Carlo simulations. The prompt gamma of nitrogen, which is a constituent of common explosive, was used to identify the unexploded ordnance (UXO). Our results show that the minimum counting time depends on the soil moisture, the cladding thickness and the explosive composition. In conjunction with the standard detection by magnetometry, the PGNAA is a promising analytical technique for definitive identification of deep buried UXOs. (author)

  2. Permeability log using new lifetime measurements

    International Nuclear Information System (INIS)

    Dowling, D.J.; Boyd, J.F.; Fuchs, J.A.

    1975-01-01

    Comparative measurements of thermal neutron decay time are obtained for a formation after irradiation with a pulsed neutron source. Chloride ions in formation fluids are concentrated by the electrosmosis effect using charged poles on a well logging sonde. The formation is irradiated with fast neutrons and a first comparative measure of the thermal neutron decay time or neutron lifetime is taken. The chloride ions are then dispersed by acoustic pumping with a magnetostrictive transducer. The formation is then again irradiated with fast neutrons and a comparative measure of neutron lifetime is taken. The comparison is a function of the variation in chloride concentration between the two measurements which is related to formation permeability

  3. Two detector pulse neutron logging porosity technique

    International Nuclear Information System (INIS)

    Schwartz, R.J.

    1971-01-01

    An illustrative embodiment of the invention discloses a technique for reducing the influence of borehole characteristics on earth formation porosity measurements. Measurements of this sort are accomplished with a borehole logging tool and comprises two neutron detectors spaced at different distances from a pulsed neutron generator. The thermal neutron decay time of the short-spaced detector identifies that portion of the time-dependent population that is most indicative of the formation porosity. Both detectors then register the portion of the neutron distribution so identified to produce two signals from which a ratio is computed that is related to the porosity of the formation. (auth)

  4. On conditional independence and log-convexity

    Czech Academy of Sciences Publication Activity Database

    Matúš, František

    2012-01-01

    Roč. 48, č. 4 (2012), s. 1137-1147 ISSN 0246-0203 R&D Projects: GA AV ČR IAA100750603; GA ČR GA201/08/0539 Institutional support: RVO:67985556 Keywords : Conditional independence * Markov properties * factorizable distributions * graphical Markov models * log-convexity * Gibbs- Markov equivalence * Markov fields * Gaussian distributions * positive definite matrices * covariance selection model Subject RIV: BA - General Mathematics Impact factor: 0.933, year: 2012 http://library.utia.cas.cz/separaty/2013/MTR/matus-0386229.pdf

  5. New radio meteor detecting and logging software

    Science.gov (United States)

    Kaufmann, Wolfgang

    2017-08-01

    A new piece of software ``Meteor Logger'' for the radio observation of meteors is described. It analyses an incoming audio stream in the frequency domain to detect a radio meteor signal on the basis of its signature, instead of applying an amplitude threshold. For that reason the distribution of the three frequencies with the highest spectral power are considered over the time (3f method). An auto notch algorithm is developed to prevent the radio meteor signal detection from being jammed by a present interference line. The results of an exemplary logging session are discussed.

  6. Zope based electronic operation log system - Zlog

    International Nuclear Information System (INIS)

    Yoshii, K.; Satoh, Y.; Kitabayashi, T.

    2004-01-01

    Since January 2004, the Zope based electronic operation logging system, named Zlog, has been running at the KEKB and AR accelerator facilities. Since Zope is the python based open source web application server software and python language is familiar for the members in the KEKB accelerator control group, we have developed the Zlog system rapidly. In this paper, we report the development history and the present status of Zlog system. Also we show some general plug-in components, called Zope products, have been useful for our Zlog development. (author)

  7. Generalized localization for the double trigonometric Fourier series and the Walsh-Fourier series of functions in L log +L log + log +L

    International Nuclear Information System (INIS)

    Bloshanskaya, S K; Bloshanskii, I L; Roslova, T Y

    1998-01-01

    For an arbitrary open set Ω subset of I 2 =[0,1) 2 and an arbitrary function f element of L log + L log + log + L(I 2 ) such that f=0 on Ω the double Fourier series of f with respect to the trigonometric system Ψ=E and the Walsh-Paley system Ψ=W is shown to converge to zero (over rectangles) almost everywhere on Ω. Thus, it is proved that generalized localization almost everywhere holds on arbitrary open subsets of the square I 2 for the double trigonometric Fourier series and the Walsh-Fourier series of functions in the class L log + L log + log + L (in the case of summation over rectangles). It is also established that such localization breaks down on arbitrary sets that are not dense in I 2 , in the classes Φ Ψ (L)(I 2 ) for the orthonormal system Ψ=E and an arbitrary function such that Φ E (u)=o(u log + log + u) as u→∞ or for Φ W (u)=u( log + log + u) 1-ε , 0<ε<1

  8. A log-linear multidimensional Rasch model for capture-recapture.

    Science.gov (United States)

    Pelle, E; Hessen, D J; van der Heijden, P G M

    2016-02-20

    In this paper, a log-linear multidimensional Rasch model is proposed for capture-recapture analysis of registration data. In the model, heterogeneity of capture probabilities is taken into account, and registrations are viewed as dichotomously scored indicators of one or more latent variables that can account for correlations among registrations. It is shown how the probability of a generic capture profile is expressed under the log-linear multidimensional Rasch model and how the parameters of the traditional log-linear model are derived from those of the log-linear multidimensional Rasch model. Finally, an application of the model to neural tube defects data is presented. Copyright © 2015 John Wiley & Sons, Ltd.

  9. Features of the determination of rock porosity from the neutron logging data at final exploration of carbonate deposits in sections of cased boreholes of old stock reserve

    International Nuclear Information System (INIS)

    Gulin, Yu.A.; Golovatskaya, I.V.

    1976-01-01

    From the analysis of the results of using methods of neutron logging in the Bashkir carbonate deposite, to enhance the reliability of singling out producing strata in the old boreholes it is recommended that impermeable strata should be omitted from consideration by singling them out on the basis of data from electric logging (well logging with two solutions, micrologging and a combination of laterolog and microfocus logging) or by neutrongamma logging and epithermal neutron logging diagrams recorded before lowering the column or immediately after lowering it into small-diameter boreholes. To determine the porosity one should use epithermal neutron logging diagrams obtained in the open borehole or recorded immediately after the lowering of the column, using in addition, for 7 3/4'' to 8 3/4''-diam boreholes, data obtained with a centred epithermal neutron logging device in the process of detailed survey

  10. Identifying APT Malware Domain Based on Mobile DNS Logging

    Directory of Open Access Journals (Sweden)

    Weina Niu

    2017-01-01

    Full Text Available Advanced Persistent Threat (APT is a serious threat against sensitive information. Current detection approaches are time-consuming since they detect APT attack by in-depth analysis of massive amounts of data after data breaches. Specifically, APT attackers make use of DNS to locate their command and control (C&C servers and victims’ machines. In this paper, we propose an efficient approach to detect APT malware C&C domain with high accuracy by analyzing DNS logs. We first extract 15 features from DNS logs of mobile devices. According to Alexa ranking and the VirusTotal’s judgement result, we give each domain a score. Then, we select the most normal domains by the score metric. Finally, we utilize our anomaly detection algorithm, called Global Abnormal Forest (GAF, to identify malware C&C domains. We conduct a performance analysis to demonstrate that our approach is more efficient than other existing works in terms of calculation efficiency and recognition accuracy. Compared with Local Outlier Factor (LOF, k-Nearest Neighbor (KNN, and Isolation Forest (iForest, our approach obtains more than 99% F-M and R for the detection of C&C domains. Our approach not only can reduce data volume that needs to be recorded and analyzed but also can be applicable to unsupervised learning.

  11. An interactive machine-learning approach for defect detection in computed tomogaraphy (CT) images of hardwood logs

    Science.gov (United States)

    Erol Sarigul; A. Lynn Abbott; Daniel L. Schmoldt; Philip A. Araman

    2005-01-01

    This paper describes recent progress in the analysis of computed tomography (CT) images of hardwood logs. The long-term goal of the work is to develop a system that is capable of autonomous (or semiautonomous) detection of internal defects, so that log breakdown decisions can be optimized based on defect locations. The problem is difficult because wood exhibits large...

  12. Technology development for high temperature logging tools

    Energy Technology Data Exchange (ETDEWEB)

    Veneruso, A.F.; Coquat, J.A.

    1979-01-01

    A set of prototype, high temperature logging tools (temperature, pressure and flow) were tested successfully to temperatures up to 275/sup 0/C in a Union geothermal well during November 1978 as part of the Geothermal Logging Instrumentation Development Program. This program is being conducted by Sandia Laboratories for the Department of Energy's Division of Geothermal Energy. The progress and plans of this industry based program to develop and apply the high temperature instrumentation technology needed to make reliable geothermal borehole measurements are described. Specifically, this program is upgrading existing sondes for improved high temperature performance, as well as applying new materials (elastomers, polymers, metals and ceramics) and developing component technology such as high temperature cables, cableheads and electronics to make borehole measurements such as formation temperature, flow rate, high resolution pressure and fracture mapping. In order to satisfy critical existing needs, the near term goal is for operation up to 275/sup 0/C and 7000 psi by the end of FY80. The long term goal is for operation up to 350/sup 0/C and 20,000 psi by the end of FY84.

  13. Public PCs: Log Out or Lose Out

    CERN Document Server

    Computer Security Team

    2013-01-01

    Do you regularly use one of the public Windows or Linux terminals in the CERN library or in front of the Users' Office? Or do you often give presentations or run meetings, workshops or conferences? Did you recently attend a training session in the CERN Training Centre? If you answered at least once with “yes”, we have a plea for you: LOG OUT when done in order to protect your data!   You might recall that CERN considers that “Your Privacy is Paramount”. But this does not come for free. In the few past months, we have received several reports from vigilant people who have spotted open user sessions on public PCs at CERN. Those users simply forgot to log out once their work, training or meeting was over. Their session continued without them being present. Worse, with CERN using a central Single Sign-On (SSO) portal, their login credentials would allow a malicious person at CERN to use those credentials to access that user’s mailbox, DFS ...

  14. Radiation incident in oil well logging

    International Nuclear Information System (INIS)

    Lozada, J.A.

    1998-01-01

    On June 4th 1997 equipment failure and violation of approved procedures by a crew of workers initiated a series of events that resulted in the unnecessary exposure to neutron and gamma radiation, from a 666 GBq Am 241 Be source, of forty two workers from a well logging company in Venezuela. Due to the presence of dry mud or drilling fluids inside the logging tool, the nosepiece was screwed off the rest of the source holder; this piece was mistaken for the entire source holder thus leaving the source inside the tool. The tool was labelled for maintenance and electronic laboratory personal worked near the source for seven hours before they identify its presence. As soon as the incident was detected a contingency plan was implemented and the source could be retrieved from the tool and placed in its shipping container. The TLD badges indicate doses well below the annual limit of 20 mSv, and none of the workers involved in the incident seem to show serious health consequences from it. After the incident, in order to avoid the occurrence of similar situations, a better source and tool maintenance program was implemented, all the workers were re-trained, and area monitors were installed in all operations bases. (author)

  15. Dual excitation acoustic paramagnetic logging tool

    Energy Technology Data Exchange (ETDEWEB)

    Vail, III, William B. (Bothell, WA)

    1989-01-01

    New methods and apparatus are disclosed which allow measurement of the presence of oil and water in gelogical formations using a new physical effect called the Acoustic Paramagnetic Logging Effect (APLE). The presence of petroleum in formation causes a slight increase in the earth's magnetic field in the vicinity of the reservoir. This is the phenomena of paramagnetism. Application of an acoustic source to a geological formation at the Larmor frequency of the nucleous present causes the paramagnetism of the formation to disappear. This results in a decrease in the earth's magnetic field in the vicinity of the oil bearing formation. Repetitively frequency sweeping the acoustic source through the Larmor frequency of the nucleons present (approx. 2 kHz) causes an amplitude modulation of the earth's magnetic field which is a consequence of the APLE. The amplitude modulation of the earth's magnetic field is measured with an induction coil gradiometer and provides a direct measure of the amount of oil and water in the excitation zone of the formation. The phase of the signal is used to infer the longitudinal relaxation times of the fluids present, which results in the ability in general to separate oil and water and to measure the viscosity of the oil present. Such measurements may be preformed in open boreholes and in cased well bores. The Dual Excitation Acoustic Paramagnetic Logging Tool employing two acoustic sources is also described.

  16. Displacement length and velocity of tagged logs in the tagliamento river

    Directory of Open Access Journals (Sweden)

    Diego Ravazzolo

    2013-09-01

    Full Text Available Large wood enhance the dynamics of geomorphic processes in river systems, increases the morphological complexity of the channel bed, and provides habitats for fish and invertebrates. On the other side, if transported during high-magnitude events, large wood pieces can increase flood risks in sensitive places such as bridges and narrow cross sections prone to outbank flows. However, the dynamics and mobility of logs in rivers is poorly understood, especially in wide gravel-bed rivers. Recent studies have employed fixed video cameras to assess logs velocity, but little evidence is still available about travel length during flood events of different magnitude. This study was conducted in a valley reach of the Tagliamento river, located in the North East of Italy. The Tagliamento river is approximately 800 m wide in the study area, and is characterized by relatively high natural conditions and complex fluvial dynamics. Log mobility have been studied from June 2010 to October 2011, a period characterized by a relatively high magnitude flood in November 2010. Log mobility and displacement during floods have been measured by implanting active radio transmitters (RFID in 113 logs and GPS track devices in 42 logs. The first devices allow to recover the log after flood events by using a portable antenna, and to derive the displacement length over the monitoring period, whereas the second devices allows to calculate instantaneous (1 sec and average log velocity of moving logs. Recovery rate of logs equipped with RFID and GPS was about 50% and 60%, respectively. A preliminary analysis of the data collected indicates that there is a positive relationship between displacement length and the peak of flood events, as well as a positive relationship between log velocity and the flood magnitude. Also, a critical flow rate over which logs stranded on active bars can be transported has been identified. The ability to predict wood mobility in gravel-bed rivers could

  17. Computation of porosity and water content from geophysical logs, Yucca Mountain, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, P.H.

    1996-12-31

    Neutron and density logs acquired in boreholes at Yucca Mountain, Nevada are used to determine porosity and water content as a function of depth. Computation of porosity requires an estimate of grain density, which is provided by core data, mineralogical data, or is inferred from rock type where neither core nor mineralogy are available. The porosity estimate is merged with mineralogical data acquired by X-ray diffraction to compute the volumetric fractions of major mineral groups. The resulting depth-based portrayal of bulk rock composition is equivalent to a whole rock analysis of mineralogy and porosity. Water content is computed from epithermal and thermal neutron logs. In the unsaturated zone, the density log is required along with a neutron log. Water content can also be computed from dielectric logs, which were acquired in only a fraction of the boreholes, whereas neutron logs were acquired in all boreholes. Mineralogical data are used to compute a structural (or bound) water estimate, which is subtracted from the total water estimate from the neutron-density combination. Structural water can be subtracted only from intervals where mineralogical analyses are available; otherwise only total water can be reported. The algorithms and procedures are applied to logs acquired during 1979 to 1984 at Yucca Mountain. Examples illustrate the results. Comparison between computed porosity and core measurements shows systematic differences ranging from 0.005 to 0.04. These values are consistent with a sensitivity analysis using uncertainty parameters for good logging conditions. Water content from core measurements is available in only one borehole, yielding a difference between computed and core-based water content of 0.006.

  18. Data Cleaning Methods for Client and Proxy Logs

    NARCIS (Netherlands)

    Weinreich, H.; Obendorf, H.; Herder, E.; Edmonds, A.; Hawkey, K.; Kellar, M.; Turnbull, D.

    2006-01-01

    In this paper we present our experiences with the cleaning of Web client and proxy usage logs, based on a long-term browsing study with 25 participants. A detailed clickstream log, recorded using a Web intermediary, was combined with a second log of user interface actions, which was captured by a

  19. Skew log-concavity of the Boros-Moll sequences.

    Science.gov (United States)

    Liu, Eric H

    2017-01-01

    Let [Formula: see text] be a triangular array of numbers. We say that [Formula: see text] is skew log-concave if for any fixed n , the sequence [Formula: see text] is log-concave. In this paper, we show that the Boros-Moll sequences are almost skew log-concave.

  20. 14 CFR 125.407 - Maintenance log: Airplanes.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Maintenance log: Airplanes. 125.407 Section... Maintenance log: Airplanes. (a) Each person who takes corrective action or defers action concerning a reported... record the action taken in the airplane maintenance log in accordance with part 43 of this chapter. (b...

  1. 31 CFR 593.309 - Round log or timber product.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Round log or timber product. 593.309 Section 593.309 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE... SANCTIONS REGULATIONS General Definitions § 593.309 Round log or timber product. The term round log or...

  2. 14 CFR 121.701 - Maintenance log: Aircraft.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Maintenance log: Aircraft. 121.701 Section... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Records and Reports § 121.701 Maintenance log... have made, a record of that action in the airplane's maintenance log. (b) Each certificate holder shall...

  3. U.S. Hardwood sawmill log procurement practices

    Science.gov (United States)

    Adrienn Andersch; Iris Montague; Urs Buehlmann; Janice K. Wiedenbeck

    2015-01-01

    U.S. hardwood sawmill log procurement practices are evolving because of the recent economic recession, market and supply chain shifts, and changing landowner objectives, among other factors. The objective of this study was to characterize the log procurement practices of hardwood sawmills and to characterize the role that log brokers play in supplying the sawmill...

  4. 47 CFR 80.1153 - Station log and radio watches.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Station log and radio watches. 80.1153 Section... SERVICES STATIONS IN THE MARITIME SERVICES Voluntary Radio Installations General § 80.1153 Station log and radio watches. (a) Licensees of voluntary ships are not required to maintain radio station logs. (b...

  5. Petroleum Potentials and Well Log Evaluation from Niger Delta Basin

    African Journals Online (AJOL)

    It has being shown that the Niger Delta Basin has spectacularly maintained a thick sedimentary apron and certain petroleum geological features favourable for petroleum generation. This study reports the petroleum potential and well log evaluation of logs in three wells to characterize the reservoir sand bodies. The well log ...

  6. Examples and counter-examples of log-symplectic manifolds

    NARCIS (Netherlands)

    Cavalcanti, Gil R.

    We study topological properties of log-symplectic structures and produce examples of compact manifolds with such structures. Notably, we show that several symplectic manifolds do not admit bona fide log-symplectic structures and several bona fide log-symplectic manifolds do not admit symplectic

  7. A survey of animal-powered logging in Alabama

    Science.gov (United States)

    Christopher W. Toms; Mark R. Dubois; John C. Bliss; John H. Wilhoit; Robert B. Rummer

    2001-01-01

    In a state with a very large, highly mechanized timber harvesting industry, animal-powered logging still occupies a niche in Alabama as a small-scale harvesting alternative. This article summarizes the results from a study that examined the extent of animal logging in Alabama. We investigated this topic by asking who is logging with animals, where are they working,...

  8. Utilization and cost of log production from animal loging operations

    Science.gov (United States)

    Suraj P. Shrestha; Bobby L. Lanford; Robert B. Rummer; Mark Dubois

    2006-01-01

    Forest harvesting with animals is a labor-intensive operation. It is expensive to use machines on smaller woodlots, which require frequent moves if mechanically logged. So, small logging systems using animals may be more cost effective. In this study, work sampling was used for five animal logging operations in Alabama to measure productive and non-productive time...

  9. Economic incentives exist to support measures to reduce illegal logging

    Science.gov (United States)

    J.A. Turner; J. Buongiorno; A. Katz; S. Zhu; R. Li

    2008-01-01

    Three studies of the global economic implications of eliminating illegal logging are summarized. Processors of illegally sourced wood would lose from the elimination of illegal logging through high prices for logs and decreased production of wood products. Associated with these changes could be losses in employment and income. Beyond these losses to the processing...

  10. Veneer-log production and receipts, North Central Region, 1970

    Science.gov (United States)

    Thomas P. Jr. Ginnaty

    1972-01-01

    The 1970 Lake States veneer-log production and mill receipts were 34.4 and 37.0 million board feet, respectively. The Central States produced 23.5 million board feet and received 30.0 million board feet of veneer logs. Veneer-log production and mill receipts dropped substantially throughout the north central region from 1968.

  11. Global impacts of Russian log export restrictions and the Canada–U.S. lumber dispute: Modeling trade in logs and lumber

    NARCIS (Netherlands)

    Kooten, van G.C.; Johnston, C.

    2014-01-01

    Forest product trade analysis is complicated by the inter-relationships among forest products. This paper deals with the development and application of an integrated log-lumber trade model that divides the globe into 20 regions. These regions play a significant role as producers and/or consumers of

  12. Theoretical studies of permeability inversion from seismoelectric logs

    Science.gov (United States)

    Hu, H.; Guan, W.; Zhao, W.

    2012-04-01

    fluid, f is the frequency. According to this approximate expression, if porosity, tortuosity and pore fluid properties (density and viscosity) have been measured by some methods or estimated by empirical formulas, permeability can be inverted by calculating tan(θEP) and using its corresponding frequency. To test this method, permeabilities of different sandstones are inverted from the synthetic full-waveform data of the seismoelectric logs. A modified inversion process is proposed based on the analysis of the inversion errors, by which the relative errors are controlled below 25% and they are smaller than those of the permeability inversion from the Stoneley wave logs. This study is supported by National Natural Science Foundations of China (41174110), Natural Science Foundation of Heilongjiang Province of China (QC2010025), Research Fund for the Doctoral Program of Higher Education of China (20102302120024), Postdoctoral Science Foundation of China (2011M500651).

  13. Use of historical logging patterns to identify disproportionately logged ecosystems within temperate rainforests of southeastern Alaska.

    Science.gov (United States)

    Albert, David M; Schoen, John W

    2013-08-01

    The forests of southeastern Alaska remain largely intact and contain a substantial proportion of Earth's remaining old-growth temperate rainforest. Nonetheless, industrial-scale logging has occurred since the 1950s within a relatively narrow range of forest types that has never been quantified at a regional scale. We analyzed historical patterns of logging from 1954 through 2004 and compared the relative rates of change among forest types, landform associations, and biogeographic provinces. We found a consistent pattern of disproportionate logging at multiple scales, including large-tree stands and landscapes with contiguous productive old-growth forests. The highest rates of change were among landform associations and biogeographic provinces that originally contained the largest concentrations of productive old growth (i.e., timber volume >46.6 m³/ha). Although only 11.9% of productive old-growth forests have been logged region wide, large-tree stands have been reduced by at least 28.1%, karst forests by 37%, and landscapes with the highest volume of contiguous old growth by 66.5%. Within some island biogeographic provinces, loss of rare forest types may place local viability of species dependent on old growth at risk of extirpation. Examination of historical patterns of change among ecological forest types can facilitate planning for conservation of biodiversity and sustainable use of forest resources. © 2013 Society for Conservation Biology.

  14. Rill erosion in burned and salvage logged western montane forests: Effects of logging equipment type, traffic level, and slash treatment

    Science.gov (United States)

    J. W. Wagenbrenner; P. R. Robichaud; R. E. Brown

    2016-01-01

    Following wildfires, forest managers often consider salvage logging burned trees to recover monetary value of timber, reduce fuel loads, or to meet other objectives. Relatively little is known about the cumulative hydrologic effects of wildfire and subsequent timber harvest using logging equipment. We used controlled rill experiments in logged and unlogged (control)...

  15. Time-lapse cased hole reservoir evaluation based on the dual-detector neutron lifetime log: the CHES II approach

    International Nuclear Information System (INIS)

    DeVries, M.R.; Fertl, W.

    1977-01-01

    A newly developed cased hole analysis technique provides detailed information on (1) reservoir rock properties, such as porosity, shaliness, and formation permeability, (2) reservoir fluid saturation, (3) distinction of oil and gas pays, (4) state of reservoir depletion, such as cumulative hydrocarbon-feet at present time and cumulative hydrocarbon-feet already depleted (e.g., the sum of both values then giving the cumulative hydrocarbon-feet originally present), and (5) monitoring of hydrocarbon/water and gas/oil contacts behind pipe. The basic well log data required for this type of analysis include the Dual-Detector Neutron Lifetime Log, run in casing at any particular time in the life of a reservoir, and the initial open-hole resistivity log. In addition, porosity information from open-hole porosity log(s) or core data is necessary. Field examples from several areas are presented and discussed in the light of formation reservoir and hydrocarbon production characteristics

  16. Nuclear magnetic logging method and system

    International Nuclear Information System (INIS)

    1979-01-01

    A nuclear magnetism logging system and method is disclosed in which a surface unit provides power to, control of, and signal reception from a downhole sonde. The surface unit comprises a source of alternating current power and switching circuit means for applying a sequence of alternating current waveforms from the alternating current power source to a surface transformer, each waveform in the sequence starting and stopping with substantially zero amplitude. A rectifier circuit is connected to a polarizing-receiving coil during the polarizing time of the polarizing-receive cycle. A receiving amplifier is connected to the polarizing-receiving coil during the receiving time of the polarizing-receive cycle. Receiver and recording circuits in the surface unit receive and record the downhole signals from the receiving amplifier. Timing circuitry controls a downhole switching circuit means for alternating the connection of the polarizing-receive coil to the rectifier and the receiving amplifier. (Auth.)

  17. Acoustic--nuclear permeability logging system

    International Nuclear Information System (INIS)

    Dowling, D.J.; Arnold, D.M.

    1978-01-01

    A down hole logging tool featuring a neutron generator, an acoustic disturbance generator, and a radiation detection system is described. An array of acoustic magnetostriction transducers is arranged about the target of a neutron accelerator. Two gamma ray sensors are separated from the accelerator target by shielding. According to the method of the invention, the underground fluid at the level of a formation is bombarded by neutrons which react with oxygen in the fluid to produce unstable nitrogen 16 particles according to the reaction 16 O(n,p) 16 N. Acoustic pulses are communicated to the fluid, and are incident on the boundary of the borehole at the formation. The resulting net flow of fluid across the boundary is determined from radiation detection measurements of the decaying 16 N particles in the fluid. A measure of the permeability of the formation is obtained from the determination of net fluid flow across the boundary

  18. Developing a theoretical basis for interpreting multisonde neutron logging

    Energy Technology Data Exchange (ETDEWEB)

    Polyachenko, A.L.; Shaposhnikova, T.A.

    1979-01-01

    The authors examine the current status of the theoretical development of multisonde neutron logging (MNK) and address the following problems in the area of MNK interpretation: 1) the formation of a multigroup, final-differential set program to calculate direct problems in the empirical curve relationships of MNK; 2) the physical nature of transfer and distribution of neutrons in a well-strata system (utilizing a simplified analytical theory); 3) the selection of the type of thermal and non-thermal neutron particles to be recorded by gamma radiation capture (which is based on a comparative analysis of total and partial error in determining the water content of strata utilizing each of these MNK modifications); 4) developing a system of calculative departure curves for both reinforced and non-reinforced oil and gas wells; 5) the construction of MNK diagrams for final strata thickness; 6) an approximation of analytical-numerical solutions to inverse MNK problems based on an analogaous inverse INNK (impulsed neutron-neutron logging) solutions; 7) an appraisal of the MNK method and associated theories for optimizing instruments and determining the limits to the information provided by this method. The need to continue research in the above areas 1, 4, 6, and 7 is underscored. Such research should be conducted on a three-dimensional rapid-acting calculation algorithm based on physical modeling.

  19. Application of multirate flowing fluid electric conductivity logging method to well DH-2, Tono Site, Japan

    Science.gov (United States)

    Doughty, Christine; Takeuchi, Shinji; Amano, Kenji; Shimo, Michito; Tsang, Chin-Fu

    2005-10-01

    In the flowing fluid electric conductivity (FEC) logging method, well bore fluid is replaced with deionized water, following which FEC profiles in the well bore are measured at a series of times while the well is pumped at a constant rate. Locations where fluid enters the well bore show peaks in the FEC logs, which are analyzed to infer inflow strengths and salinities of permeable features intersected by the borehole. In multirate flowing FEC logging, the flowing FEC logging method is repeated using two or more pumping rates. The results, coupled with those of a conventional well test over the entire borehole, enable the transmissivities and inherent pressure heads of permeable features to be determined. Multirate FEC logging is carried out on a deep borehole in fractured granitic rock using three different pumping rates. Results identify 19 hydraulically conducting fractures and indicate that transmissivity, pressure head, and salinity vary significantly among them. Using three pumping rates rather than the minimum number of two permits an internal consistency check on the analysis that provides a measure of the uncertainty of the results. Good comparisons against static FEC profiles and against independent chemical, geological, and hydrogeological data have further enhanced confidence in the results of the multirate flowing FEC logging method.

  20. Partitioned log-rank tests for the overall homogeneity of hazard rate functions.

    Science.gov (United States)

    Liu, Yukun; Yin, Guosheng

    2017-07-01

    In survival analysis, it is routine to test equality of two survival curves, which is often conducted by using the log-rank test. Although it is optimal under the proportional hazards assumption, the log-rank test is known to have little power when the survival or hazard functions cross. To test the overall homogeneity of hazard rate functions, we propose a group of partitioned log-rank tests. By partitioning the time axis and taking the supremum of the sum of two partitioned log-rank statistics over different partitioning points, the proposed test gains enormous power for cases with crossing hazards. On the other hand, when the hazards are indeed proportional, our test still maintains high power close to that of the optimal log-rank test. Extensive simulation studies are conducted to compare the proposed test with existing methods, and three real data examples are used to illustrate the commonality of crossing hazards and the advantages of the partitioned log-rank tests.

  1. National operative case log growth charts in otolaryngology-head and neck surgery training.

    Science.gov (United States)

    Jabbour, Noel; Tsue, Terance

    2015-01-01

    To report national standard case log growth curves for operative procedures in otolaryngology and to describe a method by which program directors can chart surgical case numbers over resident training to longitudinally assess sufficiency of cases and parity between residents. Data visualization and analysis. American Council for Graduate Medical Education (ACGME) national case log data for otolaryngology residency. National data set; no individual subjects. National statistical case log reports for otolaryngology were obtained from the ACGME for each postgraduate year (PGY) level in 2009, 2010, and 2011. Estimated means and standard deviations were calculated. The mean and increments of standard deviation were graphed against time to create case log growth charts, similar to pediatric growth charts. Case log growth charts were made for each ACGME Otolaryngology Residency Review Committee key indicator procedure. Progress of an individual resident or of a cohort of residents may be graphed against this growth chart background over their training time. National operative case log growth charts allow residents and program directors to graphically assess progress in obtaining a sufficient variety and number of operative procedures over time throughout training. This can provide early identification when residents begin to fall below the growth curve during training. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2014.

  2. Quality of the log-geometric distribution extrapolation for smaller undiscovered oil and gas pool size

    Science.gov (United States)

    Chenglin, L.; Charpentier, R.R.

    2010-01-01

    The U.S. Geological Survey procedure for the estimation of the general form of the parent distribution requires that the parameters of the log-geometric distribution be calculated and analyzed for the sensitivity of these parameters to different conditions. In this study, we derive the shape factor of a log-geometric distribution from the ratio of frequencies between adjacent bins. The shape factor has a log straight-line relationship with the ratio of frequencies. Additionally, the calculation equations of a ratio of the mean size to the lower size-class boundary are deduced. For a specific log-geometric distribution, we find that the ratio of the mean size to the lower size-class boundary is the same. We apply our analysis to simulations based on oil and gas pool distributions from four petroleum systems of Alberta, Canada and four generated distributions. Each petroleum system in Alberta has a different shape factor. Generally, the shape factors in the four petroleum systems stabilize with the increase of discovered pool numbers. For a log-geometric distribution, the shape factor becomes stable when discovered pool numbers exceed 50 and the shape factor is influenced by the exploration efficiency when the exploration efficiency is less than 1. The simulation results show that calculated shape factors increase with those of the parent distributions, and undiscovered oil and gas resources estimated through the log-geometric distribution extrapolation are smaller than the actual values. ?? 2010 International Association for Mathematical Geology.

  3. Controlled sliding of logs downhill by chute system integrated with portable winch and synthetic rope

    Directory of Open Access Journals (Sweden)

    Neşe Gülci

    2016-01-01

    Full Text Available Over 80% of wood extraction operations have been performed by conventional methods in Turkey. Conventional methods include skidding or sliding of logs mainly by man and animal power, which poses problems in terms of technical, economical, environmental, and ergonomic aspects. Skidding wood on plastic chutes has been implemented in limited numbers of logging applications in recent years, and provides important advantages such as reducing environmental damages and minimizing the value and volume loss of transported wood products. In this study, a chute system integrated with a mobile winch was developed for controlled sliding of large diameter logs downhill. In addition, synthetic ropes rather than steel cables were used to pull log products, resulting in a lower weight and more efficient extraction system. The system was tested on a sample wood production operation in Çınarpınar Forest Enterprise Chief of Kahramanmaraş Forest Enterprise Directorate. In the study, productivity analysis of chute system was performed and its ecological impacts were evaluated. During controlled sliding of logs downhill, the highest productivity (10.01 m3/hour was reached in the fourth chute system characterized as 36 m in length and 70% ground slope. One of the main factors that affected the productivity of chute system was the controlled sliding time of the logs. It was found that residual stand damage was very limited during controlled sliding operations.

  4. Method and apparatus for logging inclined earth boreholes

    International Nuclear Information System (INIS)

    Youmans, A.H.

    1981-01-01

    An improved technique is provided for comparing the velocity of an elongated well logging instrument traversing an inclined earth borehole with the playout velocity of the well logging cable at the earth's surface to control both the cable hoist drum rotation and the rate of movement of the subsurface instrument and thus insure cable playout is in equilibrium with the logging instrument movement. Method and apparatus are described for detecting any reduction in movement of the logging instrument through the borehole and for reducing the velocity of the logging cable playout in response thereto by reducing drum rotation. Further, when the velocity of cable playout slows to a preselected value, a monitoring circuit generates control signals which actuate a means of power attached to or integral with the logging instrument which, upon initiation, apply a force to move the logging instrument upward or downward within the borehole

  5. Crowded letter and crowded picture logMAR acuity in children with amblyopia: a quantitative comparison.

    Science.gov (United States)

    O'Boyle, Cathy; Chen, Sean I; Little, Julie-Anne

    2017-04-01

    Clinically, picture acuity tests are thought to overestimate visual acuity (VA) compared with letter tests, but this has not been systematically investigated in children with amblyopia. This study compared VA measurements with the LogMAR Crowded Kay Picture test to the LogMAR Crowded Keeler Letter acuity test in a group of young children with amblyopia. 58 children (34 male) with amblyopia (22 anisometropic, 18 strabismic and 18 with both strabismic/anisometropic amblyopia) aged 4-6 years (mean=68.7, range=48-83 months) underwent VA measurements. VA chart testing order was randomised, but the amblyopic eye was tested before the fellow eye. All participants wore up-to-date refractive correction. The Kay Picture test significantly overestimated VA by 0.098 logMAR (95% limits of agreement (LOA), 0.13) in the amblyopic eye and 0.088 logMAR (95% LOA, 0.13) in the fellow eye, respectively (pamblyopia on VA results (p>0.23). For both the amblyopic and fellow eyes, Bland-Altman plots demonstrated a systematic and predictable difference between Kay Picture and Keeler Letter charts across the range of acuities tested (Keeler acuity: amblyopic eye 0.75 to -0.05 logMAR; fellow eye 0.45 to -0.15 logMAR). Linear regression analysis (pamblyopia. Due to the predictable difference found between both crowded logMAR acuity tests, it is reasonable to adjust Kay Picture acuity thresholds by +0.10 logMAR to compute expected Keeler Letter acuity scores. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  6. Statistical methods of fracture characterization using acoustic borehole televiewer log interpretation

    Science.gov (United States)

    Massiot, Cécile; Townend, John; Nicol, Andrew; McNamara, David D.

    2017-08-01

    Acoustic borehole televiewer (BHTV) logs provide measurements of fracture attributes (orientations, thickness, and spacing) at depth. Orientation, censoring, and truncation sampling biases similar to those described for one-dimensional outcrop scanlines, and other logging or drilling artifacts specific to BHTV logs, can affect the interpretation of fracture attributes from BHTV logs. K-means, fuzzy K-means, and agglomerative clustering methods provide transparent means of separating fracture groups on the basis of their orientation. Fracture spacing is calculated for each of these fracture sets. Maximum likelihood estimation using truncated distributions permits the fitting of several probability distributions to the fracture attribute data sets within truncation limits, which can then be extrapolated over the entire range where they naturally occur. Akaike Information Criterion (AIC) and Schwartz Bayesian Criterion (SBC) statistical information criteria rank the distributions by how well they fit the data. We demonstrate these attribute analysis methods with a data set derived from three BHTV logs acquired from the high-temperature Rotokawa geothermal field, New Zealand. Varying BHTV log quality reduces the number of input data points, but careful selection of the quality levels where fractures are deemed fully sampled increases the reliability of the analysis. Spacing data analysis comprising up to 300 data points and spanning three orders of magnitude can be approximated similarly well (similar AIC rankings) with several distributions. Several clustering configurations and probability distributions can often characterize the data at similar levels of statistical criteria. Thus, several scenarios should be considered when using BHTV log data to constrain numerical fracture models.

  7. Log Distribution, Persistence, and Geomorphic Function in Streams and Rivers, in the Northeastern U.S.

    Science.gov (United States)

    St Pierre, L.; Burchsted, D.; Warren, D.

    2015-12-01

    Large wood provides critical ecosystem services such as fish habitat, temperature regulation and bank stabilization. In the northeastern U.S., the distribution of large wood is documented; however, there is little understanding of the movement, longevity and geomorphic function. This research examines the hypothesis that tree species control the persistence and geomorphic function of instream wood in the Appalachian region of the northeastern U.S. To do this, we assessed size, location, and species of logs in New Hampshire rivers, including locations in the White Mountain National Forest (WMNF) where these data were collected ten years ago. We expanded the previous dataset to include assessment of geomorphic function, including creation of diversion channels, pool formation, and sediment storage, among others. We also added new sites in the WMNF and sites on a large rural river in southwestern NH to increase the range of geomorphic variables to now include: confined and unconfined channels; 1st to 4th order streams; low to high gradient; meandering, multithreaded, and straight channels; and land use such as historic logging, modern agriculture, and post-agricultural abandonment. At each study site, we located all large logs (>10cm diameter, > 1m length) and log jams (>3 accumulated logs that provide a geomorphic function) along 100m-700m reaches. We marked each identified log with a numbered tag and recorded species, diameter, length, orientation, GPS location, tag number, and photographs. We assessed function and accumulation, decay, stability, and source classes for each log. Along each reach we measured riparian forest composition and structure and channel width. Preliminary analysis suggests that tree species significantly affects the function of logs: yellow birch and American sycamore are highly represented. Additionally, geomorphic setting also plays a primary role, where unconfined reaches have large logs that provide important functions; those functions

  8. Statistical classification of log response as an indicator of facies variation during changes in sea level

    DEFF Research Database (Denmark)

    Inwood, Jennifer; Lofi, Johanna; Davies, Sarah

    2013-01-01

    In this study, a novel application of a statistical approach is utilized for analysis of downhole logging data from Miocene-aged siliciclastic shelf sediments on the New Jersey Margin (eastern USA). A multivariate iterative nonhierarchical cluster analysis (INCA) of spectral gamma-ray logs from...... Integrated Ocean Drilling Program (IODP) Expedition 313 enables lithology within this siliciclastic succession to be inferred and, through comparison with the 1311 m of recovered core, a continuous assessment of depositional sequences is constructed. Significant changes in INCA clusters corroborate most key...

  9. Pulsed neutron uranium borehole logging with prompt fission neutrons

    International Nuclear Information System (INIS)

    Bivens, H.M.; Smith, G.W.; Jensen, D.H.

    1976-01-01

    The gross count natural gamma log normally used for uranium borehole logging is seriously affected by disequilibrium. Methods for the direct measurement of uranium, such as neutron logging, which are not affected by disequilibrium have been the object of considerable effort in recent years. This paper describes a logging system for uranium which uses a small accelerator to generate pulses of 14 MeV neutrons to detect and assay uranium by the measurement of prompt fission neutrons in the epithermal energy range. After an initial feasibility study, a prototype logging probe was built for field evaluation which began in January 1976. Physical and operational characteristics of the prototype probe, the neutron tube-transformer assembly, and the neutron tube are described. In logging operations, only the epithermal prompt fission neutrons detected between 250 microseconds to 2500 microseconds following the excitation neutron pulse are counted. Comparison of corrected neutron logs with the conventional gross count natural gamma logs and the chemical assays of cores from boreholes are shown. The results obtained with this neutron probe clearly demonstrate its advantages over the gross count natural gamma log, although at this time the accuracy of the neutron log assay is not satisfactory under some conditions. The necessary correction factors for various borehole and formation parameters are being determined and, when applied, should improve the assay accuracy

  10. Utilização de estratificação e modelo de regressão logística na análise de dados de estudos caso-controle Using of stratification and the logistic regression model in the analysis of data of case-control studies

    Directory of Open Access Journals (Sweden)

    Suely Godoy Agostinho Gimeno

    1995-08-01

    Full Text Available Exemplifica-se a aplicação de análise multivariada, por estratificação e com regressão logística, utilizando dados de um estudo caso-controle sobre câncer de esôfago. Oitenta e cinco casos e 292 controles foram classificados segundo sexo, idade e os hábitos de beber e de fumar. As estimativas por ponto dos odds ratios foram semelhantes, sendo as duas técnicas consideradas complementares.Data of a case-control study of esophageal cancer were used as an example of the use of multivariate analysis with stratification and logistic regression. Eighty-five cases and 292 controls were classified according to sex, age and smoking and drinking habits. The point estimates of the odds ratios were similar, and the techniques were considered complementary.

  11. Development of Cross-Platform Software for Well Logging Data Visualization

    Science.gov (United States)

    Akhmadulin, R. K.; Miraev, A. I.

    2017-07-01

    Well logging data processing is one of the main sources of information in the oil-gas field analysis and is of great importance in the process of its development and operation. Therefore, it is important to have the software which would accurately and clearly provide the user with processed data in the form of well logs. In this work, there have been developed a software product which not only has the basic functionality for this task (loading data from .las files, well log curves display, etc.), but can be run in different operating systems and on different devices. In the article a subject field analysis and task formulation have been performed, and the software design stage has been considered. At the end of the work the resulting software product interface has been described.

  12. Monte Carlo simulations of neutron oil well logging tools

    International Nuclear Information System (INIS)

    Azcurra, Mario O.; Zamonsky, Oscar M.

    2003-01-01

    Monte Carlo simulations of simple neutron oil well logging tools into typical geological formations are presented. The simulated tools consist of both 14 MeV pulsed and continuous Am-Be neutron sources with time gated and continuous gamma ray detectors respectively. The geological formation consists of pure limestone with 15% absolute porosity in a wide range of oil saturation. The particle transport was performed with the Monte Carlo N-Particle Transport Code System, MCNP-4B. Several gamma ray spectra were obtained at the detector position that allow to perform composition analysis of the formation. In particular, the ratio C/O was analyzed as an indicator of oil saturation. Further calculations are proposed to simulate actual detector responses in order to contribute to understand the relation between the detector response with the formation composition. (author)

  13. Transfer Entropy as a Log-Likelihood Ratio

    Science.gov (United States)

    Barnett, Lionel; Bossomaier, Terry

    2012-09-01

    Transfer entropy, an information-theoretic measure of time-directed information transfer between joint processes, has steadily gained popularity in the analysis of complex stochastic dynamics in diverse fields, including the neurosciences, ecology, climatology, and econometrics. We show that for a broad class of predictive models, the log-likelihood ratio test statistic for the null hypothesis of zero transfer entropy is a consistent estimator for the transfer entropy itself. For finite Markov chains, furthermore, no explicit model is required. In the general case, an asymptotic χ2 distribution is established for the transfer entropy estimator. The result generalizes the equivalence in the Gaussian case of transfer entropy and Granger causality, a statistical notion of causal influence based on prediction via vector autoregression, and establishes a fundamental connection between directed information transfer and causality in the Wiener-Granger sense.

  14. Monte Carlo Simulations of Neutron Oil well Logging Tools

    International Nuclear Information System (INIS)

    Azcurra, Mario

    2002-01-01

    Monte Carlo simulations of simple neutron oil well logging tools into typical geological formations are presented.The simulated tools consist of both 14 MeV pulsed and continuous Am-Be neutron sources with time gated and continuous gamma ray detectors respectively.The geological formation consists of pure limestone with 15% absolute porosity in a wide range of oil saturation.The particle transport was performed with the Monte Carlo N-Particle Transport Code System, MCNP-4B.Several gamma ray spectra were obtained at the detector position that allow to perform composition analysis of the formation.In particular, the ratio C/O was analyzed as an indicator of oil saturation.Further calculations are proposed to simulate actual detector responses in order to contribute to understand the relation between the detector response with the formation composition

  15. Penerapan Reduced Impact Logging Menggunakan Monocable Winch (Pancang Tarik (Implementing Reduced Impact Logging with Monocable Winch

    Directory of Open Access Journals (Sweden)

    Yosep Ruslim

    2012-01-01

    Full Text Available Forest harvesting still encounters many problems especially concerning impact to the residual stand  and environmental damage. Implementing the reduced impact monocable winch and planning of good skid trails should have a positive impact on work efficiency as well as, reducing damage to the residual stand and soil during felling and skidding activities. Reduced impact logging (RIL with a monocable winch (Pancang Tarik system has been tried in several IUPHHKs and it can be concluded that RIL monocable winch system could be applied practically and reduce impact on residual stand and soil damage. Using this technology has many advantages, among others: cost efficiency, locally made, environmental friendly, and high local community participation. Application of  the monocable winch  system in reduced impact logging is an effort to reduce economical and environment  damages when compared to conventional system of ground based skidding with bulldozer system. The aim of this research is to verify the efficiency (operational cost, effectiveness (productivity and  time consumption of monocable winch system. The results  indicate that the implementation monocable winch system, has reduced the soil damage as much as 8% ha-1.  The skidding cost  with monocable system is Rp95.000 m-3. This figure is significantly cheaper if compare with ground base skidding with bulldozer system in which the skidding cost around Rp165.000 m-3.Keywords: mononocable winch, productivity,  skidding cost, reduced impact logging, local community

  16. Study on fracture identification of shale reservoir based on electrical imaging logging

    Science.gov (United States)

    Yu, Zhou; Lai, Fuqiang; Xu, Lei; Liu, Lin; Yu, Tong; Chen, Junyu; Zhu, Yuantong

    2017-05-01

    In recent years, shale gas exploration has made important development, access to a major breakthrough, in which the study of mud shale fractures is extremely important. The development of fractures has an important role in the development of gas reservoirs. Based on the core observation and the analysis of laboratory flakes and laboratory materials, this paper divides the lithology of the shale reservoirs of the XX well in Zhanhua Depression. Based on the response of the mudstone fractures in the logging curve, the fracture development and logging Response to the relationship between the conventional logging and electrical imaging logging to identify the fractures in the work, the final completion of the type of fractures in the area to determine and quantify the calculation of fractures. It is concluded that the fracture type of the study area is high and the microstructures are developed from the analysis of the XX wells in Zhanhua Depression. The shape of the fractures can be clearly seen by imaging logging technology to determine its type.

  17. Acoustic reflection log in transversely isotropic formations

    Science.gov (United States)

    Ronquillo Jarillo, G.; Markova, I.; Markov, M.

    2018-01-01

    We have calculated the waveforms of sonic reflection logging for a fluid-filled borehole located in a transversely isotropic rock. Calculations have been performed for an acoustic impulse source with the characteristic frequency of tens of kilohertz that is considerably less than the frequencies of acoustic borehole imaging tools. It is assumed that the borehole axis coincides with the axis of symmetry of the transversely isotropic rock. It was shown that the reflected wave was excited most efficiently at resonant frequencies. These frequencies are close to the frequencies of oscillations of a fluid column located in an absolutely rigid hollow cylinder. We have shown that the acoustic reverberation is controlled by the acoustic impedance of the rock Z = Vphρs for fixed parameters of the borehole fluid, where Vph is the velocity of horizontally propagating P-wave; ρs is the rock density. The methods of waveform processing to determine the parameters characterizing the reflected wave have been discussed.

  18. Western tight gas sands advanced logging workshop proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Jennings, J B; Carroll, Jr, H B [eds.

    1982-04-01

    An advanced logging research program is one major aspect of the Western Tight Sands Program. Purpose of this workshop is to help BETC define critical logging needs for tight gas sands and to allow free interchange of ideas on all aspects of the current logging research program. Sixteen papers and abstracts are included together with discussions. Separate abstracts have been prepared for the 12 papers. (DLC)

  19. 12 CFR 27.4 - Inquiry/Application Log.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Inquiry/Application Log. 27.4 Section 27.4... SYSTEM § 27.4 Inquiry/Application Log. (a) The Comptroller, among other things, may require a bank to maintain a Fair Housing Inquiry/Application Log (“Log”), based upon, but not limited to, one or more of the...

  20. Erosion associated with cable and tractor logging in northwestern California

    Science.gov (United States)

    R. M. Rice; P. A. Datzman

    1981-01-01

    Abstract - Erosion and site conditions were measured at 102 logged plots in northwestern California. Erosion averaged 26.8 m 3 /ha. A log-normal distribution was a better fit to the data. The antilog of the mean of the logarithms of erosion was 3.2 m 3 /ha. The Coast District Erosion Hazard Rating was a poor predictor of erosion related to logging. In a new equation...

  1. Cost of skid roads for arch logging in West Virginia

    Science.gov (United States)

    George R., Jr. Trimble; Carl R. Barr

    1960-01-01

    In the mountain hardwood country of the northern Appalachians, tree-length skidding with tractor and arch has proved to be economical logging. One essential part of this type of logging is that tree-length logs are winched to the skid roads: tractor and arch do not run around through the woods. Winching distance is commonly 200 to 300 feet; and occasionally an extra...

  2. An artificial intelligence approach to well log correlation

    International Nuclear Information System (INIS)

    Startzman, R.A.; Kuo, T.B.

    1986-01-01

    This paper shows how an expert computer system was developed to correlate two well logs in at least moderately difficult situations. A four step process was devised to process log trace information and apply a set of rules to identify zonal correlations. Some of the advantages and problems with the artificial intelligence approach are shown using field logs. The approach is useful and, if properly and systematically applied, it can result in good correlations

  3. Modified-orientation log to assess hepatic encephalopathy.

    Science.gov (United States)

    Salam, M; Matherly, S; Farooq, I S; Stravitz, R T; Sterling, R K; Sanyal, A J; Gibson, D P; Wade, J B; Thacker, L R; Heuman, D M; Fuchs, M; Puri, P; Luketic, V; Bickston, S J; Bajaj, J S

    2012-04-01

    The subjectivity of the West-Haven criteria (WHC) hinders hepatic encephalopathy (HE) evaluation. The new HE classification has emphasised assessment of orientation. The modified-orientation log (MO-log, eight questions, scores 0-24; 24 normal) is adapted from a validated brain injury measure. To validate MO-log for HE assessment in cirrhosis. Cirrhotics admitted with/without HE were administered MO-log. We collected cirrhosis/HE details, admission/daily MO-logs and WHC (performed by different examiners), time to reach normal mentation (MO-log ≥23) and MO-log/WHC change (Δ) over day 1. Outcomes were in-hospital mortality, duration to normal mentation and length-of-stay (LOS). Regressions were performed for each outcome. MO-log inter-rater reliability was measured. Ninety-six HE (55 ± 8 years, MELD 21) and 20 non-HE (54 ± 5 years, MELD 19) in-patients were included. In HE patients, median admission WHC was 3 (range 1-4). Mean MO-log was 12 ± 8 (range 0-22). Their LOS was 6 ± 5 days and 13% died. Time to reach normal mentation was 2.4 ± 1.7 days. Concurrent validity: there was a significant negative correlation between admission MO-log and WHC (r = -0.79, P logs were significantly lower in those who died (7 vs. 12, P = 0.03) and higher in those admitted without HE (23.6 vs. 12, P log improved in 69% on day 1 (ΔMO-log 4 ± 8) which was associated with lower duration to normal mentation (2 vs. 3.5 days, P = 0.03) and mortality (3% vs.43%, P log but not WHC as a predictor. Inter-rater reliability: ICC for MO-log inter-rater observations was 0.991. Modified-orientation log is a valid tool for assessing severity and is better than West-Haven criteria in predicting outcomes in hospitalised hepatic encephalopathy patients. © 2012 Blackwell Publishing Ltd.

  4. [Computerized logP prediction using fragment methods].

    Science.gov (United States)

    Takácsné, N K

    1998-01-01

    Lipophilicity, expressed by the logarithm of octanol/water partition coefficient (logP) is an important physico-chemical property in rational drug design. Beside the experimental determination, the calculation of logP based on the chemical structure is frequently necessary. This has led to the development of numerous logP prediction methods. In the present paper the fragment type approaches and their computer softwares are surveyed (Table I.). The compilation is extended to the introduction and evaluation of a recently developed method of Meylan and Howard [21]: Atom/Fragment Contribution, AFC method (KOWWIN for Windows, software) which possesses the unique option, the Experimental Value Adjusted, EVA logP prediction. The author compared the highly precise experimental logP values of 28 drugs measured in her laboratory with calculated logP values obtained by four approaches: KOWWIN, CLOGP, PROLOGP, ACD/logP. The best prediction was found as follows in decreasing order: KOWWIN (r = 0.983), CLOGP (r = 0.978), PROLOGP/Combined (r = 0.953), ACD/logP (r = 0.942), PROLOGP/Atomic5 (r = 0.940), PROLOGP/Rekker (r = 0.909). The limits of current logP prediction methods (intramolecular H-bond formation, tautomerization, conformation changes, etc.) and the promising future of the molecular lipophilicity potential, MLP, [42] in drug design is also discussed.

  5. Real Time Face Quality Assessment for Face Log Generation

    DEFF Research Database (Denmark)

    Kamal, Nasrollahi; Moeslund, Thomas B.

    2009-01-01

    Summarizing a long surveillance video to just a few best quality face images of each subject, a face-log, is of great importance in surveillance systems. Face quality assessment is the back-bone for face log generation and improving the quality assessment makes the face logs more reliable....... Developing a real time face quality assessment system using the most important facial features and employing it for face logs generation are the concerns of this paper. Extensive tests using four databases are carried out to validate the usability of the system....

  6. Method and apparatus for uranium exploration by radioactive well logging

    International Nuclear Information System (INIS)

    Givens, W.W.

    1974-01-01

    A uranium exploration technique is described employing delayed fission neutrons from uranium in borehole logging operations to obtain both a reconnaissance log to identify possible uranium ore bearing zones and an assay log of such zones in order to obtain a qualitative indication of uranium content. In obtaining a DFN log a neutron source is operated in the borehole in order to irradiate adjacent earth material with repetitive bursts of fast neutrons which are spaced by time intervals greater than the time required for dissipation of neutrons originating in the burst. A detector is operated in order to detect delayed neutrons resulting from neutron fission of uranium. The reconnaissance and assay logging operations may be carried out in conjunction with natural gamma ray logs and also in conjunction with a logging operation to obtain the response of the earth material to moderation and absorption of neutrons. Also disclosed is a delayed fission neutron logging system which may be employed in both reconnaissance and assay logging. (author)

  7. Using a Log Analyser to Assist Research into Haptic Technology

    Science.gov (United States)

    Jónsson, Fannar Freyr; Hvannberg, Ebba Þóra

    Usability evaluations collect subjective and objective measures. Examples of the latter are time to complete a task. The paper describes use cases of a log analyser for haptic feedback. The log analyser reads a log file and extracts information such as time of each practice and assessment session, analyses whether the user goes off curve and measures the force applied. A study case using the analyser is performed using a PHANToM haptic learning environment application that is used to teach young visually impaired students the subject of polynomials. The paper answers six questions to illustrate further use cases of the log analyser.

  8. The microbial community in decaying fallen logs varies with critical period in an alpine forest.

    Science.gov (United States)

    Chang, Chenhui; Wu, Fuzhong; Yang, Wanqin; Xu, Zhenfeng; Cao, Rui; He, Wei; Tan, Bo; Justine, Meta Francis

    2017-01-01

    Little information has been available on the shifts in the microbial community in decaying fallen logs during critical periods in cold forests. Minjiang fir (Abies faxoniana) fallen logs in decay classes I-V were in situ incubated on the forest floor of an alpine forest in the eastern Tibet Plateau. The microbial community was investigated during the seasonal snow cover period (SP), snow thawing period (TP), early growing season (EG) and late growing season (LG) using Phosphorous Lipid Fatty Acid (PLFA) analysis. Total microbial biomass and microbial diversity in fallen logs were much more affected by critical period than decay class, whereas decay class had a stronger effect on microbial diversity than on microbial biomass. Abundant microbial biomass and microbial diversity in logs even without the cover of snow were observed in winter, which could not be linked to thermal insulation by snow cover. The freshly decayed logs functioned as an excellent buffer of environmental variation for microbial organisms during the sharp fluctuations in temperature in winter. We also found distinct decay patterns along with seasonality for heartwood, sapwood and bark, which requires further detailed research. Gram- bacteria mainly dominated the shifts in microbial community composition from SP to EG, while fungi and Gram+ bacteria mainly dominated it from SP to TP. Based on previous work and the present study, we conclude that fallen logs on the forest floor alter ecological processes by influencing microbial communities on woody debris and beneath the soil and litter. Our study also emphasizes the need to maintain a number of fallen logs, especially fresh ones, on the forest floor.

  9. Use of an automated case log to improve trainee evaluations on a pediatric emergency medicine rotation.

    Science.gov (United States)

    Nagler, Joshua; Pina, Carina; Weiner, Debra L; Nagler, Alisa; Monuteaux, Michael C; Bachur, Richard G

    2013-03-01

    Providing meaningful evaluation to trainees rotating through the pediatric emergency medicine is important yet challenging. Information systems can be used to autopopulate an electronic case log, which can be leveraged to assist in the evaluation process. The objective of this study was to determine if a novel educational initiative using an automated case log improved faculty evaluation of trainees. This retrospective study examined faculty completion rate, as well as the content of medical student evaluations over a 3-academic-year study period. Three phases of evaluation were utilized: written, electronic, and electronic enhanced with individualized case reports created with the automated case log. The primary outcome was faculty response rate. Secondary outcomes included word count and the number of themes identified following qualitative analysis of narrative responses. Logistic regression was performed. Forty-one faculty members completed evaluations of 43 students. The rates of completion for the written, electronic, and automated case log phases were 18%, 16%, and 62%, respectively. Faculty in the automated case log phase were significantly more likely to complete evaluations compared with those in the written evaluation phase (odds ratio, 7.6; 95% confidence interval, 4.5-13.0). The median word counts across the 3 phases were 19, 36, and 43, respectively. The median numbers of themes identified during the 3 phases were 3, 4, and 5, respectively. The differences in the word count and median number of themes between the written and automated case log phases were significantly different (P log to provide faculty members with individualized reports of shared patient encounters.

  10. SU-F-T-233: Evaluation of Treatment Delivery Parameters Using High Resolution ELEKTA Log Files

    International Nuclear Information System (INIS)

    Kabat, C; Defoor, D; Alexandrian, A; Papanikolaou, N; Stathakis, S

    2016-01-01

    Purpose: As modern linacs have become more technologically advanced with the implementation of IGRT and IMRT with HDMLCs, a requirement for more elaborate tracking techniques to monitor components’ integrity is paramount. ElektaLog files are generated every 40 milliseconds, which can be analyzed to track subtle changes and provide another aspect of quality assurance. This allows for constant monitoring of fraction consistency in addition to machine reliability. With this in mind, it was the aim of the study to evaluate if ElektaLog files can be utilized for linac consistency QA. Methods: ElektaLogs were reviewed for 16 IMRT patient plans with >16 fractions. Logs were analyzed by creating fluence maps from recorded values of MLC locations, jaw locations, and dose per unit time. Fluence maps were then utilized to calculate a 2D gamma index with a 2%–2mm criteria for each fraction. ElektaLogs were also used to analyze positional errors for MLC leaves and jaws, which were used to compute an overall error for the MLC banks, Y-jaws, and X-jaws by taking the root-meansquare value of the individual recorded errors during treatment. Additionally, beam on time was calculated using the number of ElektaLog file entries within the file. Results: The average 2D gamma for all 16 patient plans was found to be 98.0±2.0%. Recorded gamma index values showed an acceptable correlation between fractions. Average RMS values for MLC leaves and the jaws resulted in a leaf variation of roughly 0.3±0.08 mm and jaw variation of about 0.15±0.04 mm, both of which fall within clinical tolerances. Conclusion: The use of ElektaLog files for day-to-day evaluation of linac integrity and patient QA can be utilized to allow for reliable analysis of system accuracy and performance.

  11. SU-F-T-233: Evaluation of Treatment Delivery Parameters Using High Resolution ELEKTA Log Files

    Energy Technology Data Exchange (ETDEWEB)

    Kabat, C; Defoor, D; Alexandrian, A; Papanikolaou, N; Stathakis, S [University of Texas HSC SA, San Antonio, TX (United States)

    2016-06-15

    Purpose: As modern linacs have become more technologically advanced with the implementation of IGRT and IMRT with HDMLCs, a requirement for more elaborate tracking techniques to monitor components’ integrity is paramount. ElektaLog files are generated every 40 milliseconds, which can be analyzed to track subtle changes and provide another aspect of quality assurance. This allows for constant monitoring of fraction consistency in addition to machine reliability. With this in mind, it was the aim of the study to evaluate if ElektaLog files can be utilized for linac consistency QA. Methods: ElektaLogs were reviewed for 16 IMRT patient plans with >16 fractions. Logs were analyzed by creating fluence maps from recorded values of MLC locations, jaw locations, and dose per unit time. Fluence maps were then utilized to calculate a 2D gamma index with a 2%–2mm criteria for each fraction. ElektaLogs were also used to analyze positional errors for MLC leaves and jaws, which were used to compute an overall error for the MLC banks, Y-jaws, and X-jaws by taking the root-meansquare value of the individual recorded errors during treatment. Additionally, beam on time was calculated using the number of ElektaLog file entries within the file. Results: The average 2D gamma for all 16 patient plans was found to be 98.0±2.0%. Recorded gamma index values showed an acceptable correlation between fractions. Average RMS values for MLC leaves and the jaws resulted in a leaf variation of roughly 0.3±0.08 mm and jaw variation of about 0.15±0.04 mm, both of which fall within clinical tolerances. Conclusion: The use of ElektaLog files for day-to-day evaluation of linac integrity and patient QA can be utilized to allow for reliable analysis of system accuracy and performance.

  12. Classification errors in contingency tables analyzed with hierarchical log-linear models. Technical report No. 20

    Energy Technology Data Exchange (ETDEWEB)

    Korn, E L

    1978-08-01

    This thesis is concerned with the effect of classification error on contingency tables being analyzed with hierarchical log-linear models (independence in an I x J table is a particular hierarchical log-linear model). Hierarchical log-linear models provide a concise way of describing independence and partial independences between the different dimensions of a contingency table. The structure of classification errors on contingency tables that will be used throughout is defined. This structure is a generalization of Bross' model, but here attention is paid to the different possible ways a contingency table can be sampled. Hierarchical log-linear models and the effect of misclassification on them are described. Some models, such as independence in an I x J table, are preserved by misclassification, i.e., the presence of classification error will not change the fact that a specific table belongs to that model. Other models are not preserved by misclassification; this implies that the usual tests to see if a sampled table belong to that model will not be of the right significance level. A simple criterion will be given to determine which hierarchical log-linear models are preserved by misclassification. Maximum likelihood theory is used to perform log-linear model analysis in the presence of known misclassification probabilities. It will be shown that the Pitman asymptotic power of tests between different hierarchical log-linear models is reduced because of the misclassification. A general expression will be given for the increase in sample size necessary to compensate for this loss of power and some specific cases will be examined.

  13. Implications of sampling from a log-normal population

    International Nuclear Information System (INIS)

    Toy, A.J.; Lindeken, C.L.

    1975-01-01

    The environmental radioactivity surrounding the Lawrence Livermore Laboratory (LLL) is typically log-normally distributed. The geometric standard deviation of radioactivity in all types of samples (air, water, soil, sewage, and vegetation) is about two. Hypothesis testing was done using the mean geometric standard deviation of these samples. Parametric studies demonstrated the effect of the number of background samples, the magnitude of tolerable errors, the variability of the sample population, and the precision of the analysis on the detectability of differences from natural and global fallout radioactivity. It was decided to accept an error probability of 50 percent that the analysis would show a sample to be different from background when, in fact, it was not, and an error probability of 5 percent that the analysis would show a sample to be background, when in fact, it was not. For these assumptions, an analysis must differ from background by a factor of 1.6 to indicate a statistical difference, and a sample must contain radioactivity a factor of 8.6 different from background to be 95 percent detectable with 50 percent confidence. The difference in the mean of two such populations which is 95 percent detectable with 50 percent confidence is 2.8 if six samples are taken from each population. Applications in monitoring 239 Pu diffusion are described. (CH)

  14. Implications of sampling from a log-normal population

    International Nuclear Information System (INIS)

    Toy, A.J.; Lindeken, C.L.

    1975-01-01

    The environmental radioactivity surrounding the Lawrence Livermore Laboratory is typically log-normally distributed. The geometric standard deviation of radioactivity in all types of samples--air, water, soil, sewage, and vegetation--is about two. Hypothesis testing was done using the mean geometric standard deviation of these samples. Parametric studies demonstrated the effect of the number of background samples, the magnitude of tolerable errors, the variability of the sample population, and the precision of the analysis on the detectability of differences from natural and global fallout radioactivity. It was decided to accept an error probability of 50 percent that the analysis would show a sample to be different from background when, in fact, it was not, and an error probability of 5 percent that the analysis would show a sample to be background, when in fact, it was not. For these assumptions, an analysis must differ from background by a factor of 1.6 to indicate a statistical difference, and a sample must contain radioactivity a factor of 8.6 different from background to be 95 percent detectable with 50 percent confidence. The difference in the mean of two such populations which is 95 percent detectable with 50 percent confidence is 2.8 if six samples are taken from each population

  15. Reading Logs and Literature Teaching Models in English Language Teacher Education

    Science.gov (United States)

    Ochoa Delarriva, Ornella; Basabe, Enrique Alejandro

    2016-01-01

    Reading logs are regularly used in foreign language education since they are not only critical in the development of reading comprehension but may also be instrumental in taking readers beyond the referential into the representational realms of language. In this paper we offer the results of a qualitative analysis of a series of reading logs…

  16. A watershed's response to logging and roads: South Fork of Caspar Creek, California, 1967-1976

    Science.gov (United States)

    Raymond M. Rice; Forest B. Tilley; Patricia A. Datzman

    1979-01-01

    The effect of logging and roadbuilding on erosion and sedimentation are analyzed by comparing the North Fork and South Fork of Caspar Creek, in northern California. Increased sediment production during the 4 years after road construction, was 326 cu yd/sq mi/yr—80 percent greater than that predicted by the predisturbance regression analysis. The average...

  17. Watching the Whites of Their Eyes: The Use of Teaching-Practice Logs.

    Science.gov (United States)

    Thornbury, Scott

    1991-01-01

    Describes the piloting of diaries to record self-assessments of teaching-practice lessons for trainees for the Royal Society of Arts Cambridge Certificate in Teaching English as a foreign language (TEFLA). An analysis of these training logs suggests they are instrumental in the development of personal theories of learning and teaching. (15…

  18. Learning analytics in serious gaming: uncovering the hidden treasury of game log files

    NARCIS (Netherlands)

    Westera, Wim; Nadolski, Rob; Hummel, Hans

    2018-01-01

    This paper presents an exploratory analysis of existing log files of the VIBOA environmental policy games at Utrecht University. For reasons of statistical power we’ve combined student cohorts 2008, 2009, 2010, and 2011, which led to a sample size of 118 students. The VIBOA games are inquiry-based

  19. Opening the Black Box of Electronic Health: Collecting, Analyzing, and Interpreting Log Data.

    Science.gov (United States)

    Sieverink, Floor; Kelders, Saskia; Poel, Mannes; van Gemert-Pijnen, Lisette

    2017-08-07

    In electronic health (eHealth) research, limited insight has been obtained on process outcomes or how the use of technology has contributed to the users' ability to have a healthier life, improved well-being, or activate new attitudes in their daily tasks. As a result, eHealth is often perceived as a black box. To open this black box of eHealth, methodologies must extend beyond the classic effect evaluations. The analyses of log data (anonymous records of real-time actions performed by each user) can provide continuous and objective insights into the actual usage of the technology. However, the possibilities of log data in eHealth research have not been exploited to their fullest extent. The aim of this paper is to describe how log data can be used to improve the evaluation and understand the use of eHealth technology with a broader approach than only descriptive statistics. This paper serves as a starting point for using log data analysis in eHealth research. Here, we describe what log data is and provide an overview of research questions to evaluate the system, the context, the users of a technology, as well as the underpinning theoretical constructs. We also explain the requirements for log data, the starting points for the data preparation, and methods for data collection. Finally, we describe methods for data analysis and draw a conclusion regarding the importance of the results for both scientific and practical applications. The analysis of log data can be of great value for opening the black box of eHealth. A deliberate log data analysis can give new insights into how the usage of the technology contributes to found effects and can thereby help to improve the persuasiveness and effectiveness of eHealth technology and the underpinning behavioral models. ©Floor Sieverink, Saskia Kelders, Mannes Poel, Lisette van Gemert-Pijnen. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 07.08.2017.

  20. How effective are task forces in tackling illegal logging? Empirical evidence from Ghana

    DEFF Research Database (Denmark)

    Franck, Marte; Hansen, Christian Pilegaard

    2014-01-01

    not proven effective in Ghana. The task forces are influenced by corruption; interference by powerful actors; fear of violence; and logistical and resource-related challenges. The paper suggests that effectively addressing illegal logging in Ghana will require a more normative approach that involves policy......This paper analyses the experiences and effectiveness of timber task forces to combat illegal logging. The paper is based on an analysis of 30 semi-structured interviews with members of timber task forces and other relevant stakeholders in Ghana. The paper finds that task forces have generally...

  1. Fast inference in generalized linear models via expected log-likelihoods

    Science.gov (United States)

    Ramirez, Alexandro D.; Paninski, Liam

    2015-01-01

    Generalized linear models play an essential role in a wide variety of statistical applications. This paper discusses an approximation of the likelihood in these models that can greatly facilitate computation. The basic idea is to replace a sum that appears in the exact log-likelihood by an expectation over the model covariates; the resulting “expected log-likelihood” can in many cases be computed significantly faster than the exact log-likelihood. In many neuroscience experiments the distribution over model covariates is controlled by the experimenter and the expected log-likelihood approximation becomes particularly useful; for example, estimators based on maximizing this expected log-likelihood (or a penalized version thereof) can often be obtained with orders of magnitude computational savings compared to the exact maximum likelihood estimators. A risk analysis establishes that these maximum EL estimators often come with little cost in accuracy (and in some cases even improved accuracy) compared to standard maximum likelihood estimates. Finally, we find that these methods can significantly decrease the computation time of marginal likelihood calculations for model selection and of Markov chain Monte Carlo methods for sampling from the posterior parameter distribution. We illustrate our results by applying these methods to a computationally-challenging dataset of neural spike trains obtained via large-scale multi-electrode recordings in the primate retina. PMID:23832289

  2. 252Cf-based direct uranium logging system. Volume 1. Final report

    International Nuclear Information System (INIS)

    Steinman, D.K.; Stokes, J.; Adams, J.A.; Pepper, C.S.; Bryan, D.E.; Smith, W.J.; Atwell, T.; Friesenhahn, S.; Dittrich, T.R.; Houston, D.H.

    1980-01-01

    To reduce both the uncertainties and costs of current methods, a 252 Cf-based borehole logging system was developed for in situ assay of uranium. This system utilized Delayed Neutron Activation Analysis (DNAA) to identify uniquely and to quantify a uranium occurrence. Thermal neutrons emitted by the 252 Cf system penetrate 15 cm into the surrounding formation and, if uranium is present, will cause fission of 235 U. The resulting fission products emit various characteristic types of radiation, including delayed neutrons. Since the background interference from natural neutron sources is essentially zero, the delayed neutrons are used to identify and quantify uranium even at concentrations significantly less than 100 ppM. This uranium borehole logging system was demonstrated successfully in the field in 1976. The system was a prototype based on the shuttling of the 252 Cf source between two locations in the logging probe. This method produces a large increase in sensitivity over the stationary source 252 Cf DNAA probe

  3. Practical Aspects of Log-ratio Coordinate Representations in Regression with Compositional Response

    Directory of Open Access Journals (Sweden)

    Fišerová Eva

    2016-10-01

    Full Text Available Regression analysis with compositional response, observations carrying relative information, is an appropriate tool for statistical modelling in many scientific areas (e.g. medicine, geochemistry, geology, economics. Even though this technique has been recently intensively studied, there are still some practical aspects that deserve to be further analysed. Here we discuss the issue related to the coordinate representation of compositional data. It is shown that linear relation between particular orthonormal coordinates and centred log-ratio coordinates can be utilized to simplify the computation concerning regression parameters estimation and hypothesis testing. To enhance interpretation of regression parameters, the orthogonal coordinates and their relation with orthonormal and centred log-ratio coordinates are presented. Further we discuss the quality of prediction in different coordinate system. It is shown that the mean squared error (MSE for orthonormal coordinates is less or equal to the MSE for log-transformed data. Finally, an illustrative real-world example from geology is presented.

  4. Kirjaliku produtseerimisprotsessi uurimise võimalused programmi ScriptLog abil: juhtumiuuring

    Directory of Open Access Journals (Sweden)

    Olga Pastuhhova

    2011-10-01

    Full Text Available Computer keystroke logging is a technique for recording writing in real-time. It is based on a cognitive approach to writing and presents a writer-based perspective, as opposed to the analysis of writer’s final text or product. The focus of this article is to provide an overview of possibilities for writing process research made available by the rapid development of echnology. The article first presents computer keystroke logging as a relevant method among others, and discusses previous research based on the method. This is followed by a case study of the writing process of a native Russian learner of Estonian as a second language with target language proficiency at the C1 level. The data was collected using the ScriptLog computer programme, which keeps a detailed record of the writer’s activity on the keyboard combined with a retrospective interview.

  5. Error Propagation in Isometric Log-ratio Coordinates for Compositional Data: Theoretical and Practical Considerations.

    Science.gov (United States)

    Mert, Mehmet Can; Filzmoser, Peter; Hron, Karel

    2016-01-01

    Compositional data, as they typically appear in geochemistry in terms of concentrations of chemical elements in soil samples, need to be expressed in log-ratio coordinates before applying the traditional statistical tools if the relative structure of the data is of primary interest. There are different possibilities for this purpose, like centered log-ratio coefficients, or isometric log-ratio coordinates. In both the approaches, geometric means of the compositional parts are involved, and it is unclear how measurement errors or detection limit problems affect their presentation in coordinates. This problem is investigated theoretically by making use of the theory of error propagation. Due to certain limitations of this approach, the effect of error propagation is also studied by means of simulations. This allows to provide recommendations for practitioners on the amount of error and on the expected distortion of the results, depending on the purpose of the analysis.

  6. Practical Aspects of Log-ratio Coordinate Representations in Regression with Compositional Response

    Science.gov (United States)

    Fišerová, Eva; Donevska, Sandra; Hron, Karel; Bábek, Ondřej; Vaňkátová, Kristýna

    2016-10-01

    Regression analysis with compositional response, observations carrying relative information, is an appropriate tool for statistical modelling in many scientific areas (e.g. medicine, geochemistry, geology, economics). Even though this technique has been recently intensively studied, there are still some practical aspects that deserve to be further analysed. Here we discuss the issue related to the coordinate representation of compositional data. It is shown that linear relation between particular orthonormal coordinates and centred log-ratio coordinates can be utilized to simplify the computation concerning regression parameters estimation and hypothesis testing. To enhance interpretation of regression parameters, the orthogonal coordinates and their relation with orthonormal and centred log-ratio coordinates are presented. Further we discuss the quality of prediction in different coordinate system. It is shown that the mean squared error (MSE) for orthonormal coordinates is less or equal to the MSE for log-transformed data. Finally, an illustrative real-world example from geology is presented.

  7. Development and application of storage-type density meter for oil logging

    International Nuclear Information System (INIS)

    Sun Punan

    2009-01-01

    A storage-type density meter for oil logging has been developed. It constitutes of a 137 Cs source, a NaI scintillation detector, a pulse amplifier, a date storage circuit, a high voltage power supply and a Li ion battery, being integrated into a stainless steel container of Φ60 mm x 1300 mm. Unlike density meters in current uses, this type of density meter goes into an oil well without an armored cable. Density data acquired in the well are stored for data analysis with a PC in laboratory. The density distribution derived from oil well can be a guide for oil exploration. Logging of the density meter can be done with only one crane, for a continuous logging of up to 15 days. (authors)

  8. Prediction of Log "P": ALOGPS Application in Medicinal Chemistry Education

    Science.gov (United States)

    Kujawski, Jacek; Bernard, Marek K.; Janusz, Anna; Kuzma, Weronika

    2012-01-01

    Molecular hydrophobicity (lipophilicity), usually quantified as log "P" where "P" is the partition coefficient, is an important molecular characteristic in medicinal chemistry and drug design. The log "P" coefficient is one of the principal parameters for the estimation of lipophilicity of chemical compounds and pharmacokinetic properties. The…

  9. Erosion control on logging roads in the Appalachians

    Science.gov (United States)

    James N. Kochenderfer; James N. Kochenderfer

    1970-01-01

    In the steep terrain of the Appalachian Mountains much damage to forest streams is caused by erosion on logging roads. Muddy water that is unsuitable for fish, swimming, or human consumption often can be traced to these eroding roads. This paper has been prepared to sum up what land managers know about preventing and controlling erosion on logging roads in the...

  10. Assessment of procurement systems for unutilized logging residues ...

    African Journals Online (AJOL)

    The results showed that coarse logging residues can be available as firewood in traditional utilization manner, but a thin material is left in the forest because of high collection and extraction costs. However, it was found that the increasing demand for forest biomass as a bioenergy resource encouraged the use of logging ...

  11. The application of seismic-log sequence stratigraphy in mapping ...

    African Journals Online (AJOL)

    The concept of seismic-log sequence stratigraphy was used in mapping stratigraphic traps and reservoirs' facies in Afam Channel area, Niger Delta, for the purpose of prospect re-evaluation and improving production. The data set consists of 3-D seismic data and conventional well logs, which were interpreted iteratively ...

  12. Biased estimation of forest log characteristics using intersect diameters

    Science.gov (United States)

    Lisa J. Bate; Torolf R. Torgersen; Michael J. Wisdom; Edward O. Garton

    2009-01-01

    Logs are an important structural feature of forest ecosystems, and their abundance affects many resources and forest processes, including fire regimes, soil productivity, silviculture, carbon cycling, and wildlife habitat. Consequently, logs are often sampled to estimate their frequency, percent cover, volume, and weight. The line-intersect method (LIM) is one of the...

  13. Comparing GPS, Log, Survey, and Accelerometry to Measure Physical Activity.

    Science.gov (United States)

    James, Peter; Weissman, Jennifer; Wolf, Jean; Mumford, Karen; Contant, Cheryl K; Hwang, Wei-Ting; Taylor, Lynne; Glanz, Karen

    2016-01-01

    We explored how objectively measured global positioning system (GPS) and accelerometer data match with travel logs and questionnaires in predicting trip duration and physical activity (PA). 99 participants wore GPS devices and accelerometers, and recorded all trips in a log for 5 consecutive days. Participants also completed a self-administered questionnaire on PA and travel behaviors. There was good agreement between GPS and log for assessment of trip duration, although log measures overestimated trip duration (concordance correlation coefficient 0.53 [0.47, 0.59]; Bland-Altman estimate 0.76 [0.16, 3.71] comparing GPS to log). Log measures underestimated light PA and overestimated moderate PA compared to accelerometry when greater than zero moderate PA was reported. It is often not feasible to deploy accelerometry or GPS devices in population research because these devices are expensive and require technical expertise and data processing. Questionnaires and logs provide inexpensive tools to assess PA and travel with reasonable concordance with objective measures. However, they have shortcomings in evaluating the presence and amount of light and moderate PA. Future questionnaires and logs should be developed to evaluate sensitivity to light and moderate PA.

  14. 46 CFR 78.37-10 - Official log entires.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Official log entires. 78.37-10 Section 78.37-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS OPERATIONS Logbook Entries § 78.37-10 Official log entires. (a) In addition to other items required to be entered in the official...

  15. Butt-log grade distributions for five Appalachian hardwood species

    Science.gov (United States)

    John R. Myers; Gary W. Miller; Harry V., Jr. Wiant; Joseph E. Barnard; Joseph E. Barnard

    1986-01-01

    Tree quality is an important factor in determining the market value of hardwood timber stands, but many forest inventories do not include estimates of tree quality. Butt-log grade distributions were developed for northern red oak, black oak, white oak, chestnut oak, and yellow-poplar using USDA Forest Service log grades on more than 4,700 trees in West Virginia. Butt-...

  16. Ubiquitous Learning Project Using Life-Logging Technology in Japan

    Science.gov (United States)

    Ogata, Hiroaki; Hou, Bin; Li, Mengmeng; Uosaki, Noriko; Mouri, Kosuke; Liu, Songran

    2014-01-01

    A Ubiquitous Learning Log (ULL) is defined as a digital record of what a learner has learned in daily life using ubiquitous computing technologies. In this paper, a project which developed a system called SCROLL (System for Capturing and Reusing Of Learning Log) is presented. The aim of developing SCROLL is to help learners record, organize,…

  17. Logging residues under different stand and harvesting conditions, Rocky Mountains

    Science.gov (United States)

    Robert E. Benson; Cameron M. Johnston

    1976-01-01

    Volume and characteristics of logging residues from 34 harvest areas are presented. Clearcuts and partial cuts logged to conventional utilization levels and to close utilization levels are included. Residue volumes ranged from almost 3, 600 ft3 /acre of wood 3-inches-plus down to about 550 ft3 /acre, depending on treatment. More than 60 percent of the residues were...

  18. A selective logging mechanism for hardware transactional memory systems

    OpenAIRE

    Lupon Navazo, Marc; Magklis, Grigorios; González Colás, Antonio María

    2011-01-01

    Log-based Hardware Transactional Memory (HTM) systems offer an elegant solution to handle speculative data that overflow transactional L1 caches. By keeping the pre-transactional values on a software-resident log, speculative values can be safely moved across the memory hierarchy, without requiring expensive searches on L1 misses or commits.

  19. Secure Audit Logging with Tamper-Resistant Hardware

    NARCIS (Netherlands)

    Chong, C.N.; Peng, Z.; Peng, Z.; Hartel, Pieter H.; Gritzalis, D.; De Capitani di Vimercati, S.; Katsikas, S.K.; Samarati, P.

    Secure perimeter schemes (e.g. DRM) and tracing traitor schemes (e.g. watermarking, audit logging) strive to mitigate the problems of content escaping the control of the rights holder. Secure audit logging records the user's actions on content and enables detection of some forms of tampering with

  20. Modelling discontinuous well log signal to identify lithological ...

    Indian Academy of Sciences (India)

    Identification of sharp and discontinuous lithological boundaries from well log signal stemming from heterogeneous subsurface structures assumes a special significance in geo-exploration studies. Well log data acquired from various geological settings generally display nonstationary/nonlinear characteristics with varying ...

  1. Logging activities in mangrove forests: A case study of Douala ...

    African Journals Online (AJOL)

    Logging activities in mangrove forests: A case study of Douala Cameroon. N Din, P Saenger, P.R. Jules, D.D. Siegfried, F Basco. Abstract. The Cameroon mangroves are exploited by local communities through fishing, hunting, and especially logging for fuel-wood and charcoal. The changing demographic patterns in the ...

  2. Condition and fate of logged forests in the Brazilian Amazon.

    Science.gov (United States)

    Gregory P. Asner; Eben N. Broadbent; Paulo J. C. Oliveira; Michael Keller; David E. Knapp; Jose N. M. Silva

    2006-01-01

    The long-term viability of a forest industry in the Amazon region of Brazil depends on the maintenance of adequate timber volume and growth in healthy forests. Using extensive high-resolution satellite analyses, we studied the forest damage caused by recent logging operations and the likelihood that logged forests would be cleared within 4 years after timber harvest....

  3. Modelling discontinuous well log signal to identify lithological ...

    Indian Academy of Sciences (India)

    ter level forecasting (Adamowski and Chan 2011). KTB research geoscientist team has examined the fractal behaviour of well-log signal variabil- ity, presuming that well-log signals in the super deep German Continental Deep Drilling Program. (KTB) borehole display nonlinear characteristics. (Leonardi and Kumpel 1999).

  4. Teaching an Old Log New Tricks with Machine Learning.

    Science.gov (United States)

    Schnell, Krista; Puri, Colin; Mahler, Paul; Dukatz, Carl

    2014-03-01

    To most people, the log file would not be considered an exciting area in technology today. However, these relatively benign, slowly growing data sources can drive large business transformations when combined with modern-day analytics. Accenture Technology Labs has built a new framework that helps to expand existing vendor solutions to create new methods of gaining insights from these benevolent information springs. This framework provides a systematic and effective machine-learning mechanism to understand, analyze, and visualize heterogeneous log files. These techniques enable an automated approach to analyzing log content in real time, learning relevant behaviors, and creating actionable insights applicable in traditionally reactive situations. Using this approach, companies can now tap into a wealth of knowledge residing in log file data that is currently being collected but underutilized because of its overwhelming variety and volume. By using log files as an important data input into the larger enterprise data supply chain, businesses have the opportunity to enhance their current operational log management solution and generate entirely new business insights-no longer limited to the realm of reactive IT management, but extending from proactive product improvement to defense from attacks. As we will discuss, this solution has immediate relevance in the telecommunications and security industries. However, the most forward-looking companies can take it even further. How? By thinking beyond the log file and applying the same machine-learning framework to other log file use cases (including logistics, social media, and consumer behavior) and any other transactional data source.

  5. Landslides after clearcut logging in a coast redwood forest

    Science.gov (United States)

    Leslie M. Reid; Elizabeth T. Keppeler

    2012-01-01

    Landslides have been mapped at least annually in the 473 ha North Fork Caspar Creek watershed since 1985, allowing evaluation of landslide distribution, characteristics, and rates associated with second-entry partial clearcut logging of 1989 to 1992. Comparison of sliding rates in logged and forested areas shows no appreciable difference for streamside slides (size...

  6. The Log-Linear Return Approximation, Bubbles, and Predictability

    DEFF Research Database (Denmark)

    Engsted, Tom; Pedersen, Thomas Quistgaard; Tanggaard, Carsten

    2012-01-01

    We study in detail the log-linear return approximation introduced by Campbell and Shiller (1988a). First, we derive an upper bound for the mean approximation error, given stationarity of the log dividend-price ratio. Next, we simulate various rational bubbles which have explosive conditional expe...

  7. 21 CFR 211.182 - Equipment cleaning and use log.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Equipment cleaning and use log. 211.182 Section 211.182 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Reports § 211.182 Equipment cleaning and use log. A written record of major equipment cleaning...

  8. Fates of trees damaged by logging in Amazonian Bolivia

    NARCIS (Netherlands)

    Shenkin, A.; Bolker, B.; Peña Claros, M.; Licona, J.C.; Putz, F.E.

    2015-01-01

    Estimation of carbon losses from trees felled and incidentally-killed during selective logging of tropical forests is relatively straightforward and well-documented, but less is known about the fates of collaterally-damaged trees that initially survive. Tree response to logging damage is an

  9. Inversion of a lateral log using neural networks

    International Nuclear Information System (INIS)

    Garcia, G.; Whitman, W.W.

    1992-01-01

    In this paper a technique using neural networks is demonstrated for the inversion of a lateral log. The lateral log is simulated by a finite difference method which in turn is used as an input to a backpropagation neural network. An initial guess earth model is generated from the neural network, which is then input to a Marquardt inversion. The neural network reacts to gross and subtle data features in actual logs and produces a response inferred from the knowledge stored in the network during a training process. The neural network inversion of lateral logs is tested on synthetic and field data. Tests using field data resulted in a final earth model whose simulated lateral is in good agreement with the actual log data

  10. Linking Hunter Knowledge with Forest Change to Understand Changing Deer Harvest Opportunities in Intensively Logged Landscapes

    Directory of Open Access Journals (Sweden)

    Todd J. Brinkman

    2009-06-01

    Full Text Available The effects of landscape changes caused by intensive logging on the availability of wild game are important when the harvest of wild game is a critical cultural practice, food source, and recreational activity. We assessed the influence of extensive industrial logging on the availability of wild game by drawing on local knowledge and ecological science to evaluate the relationship between forest change and opportunities to harvest Sitka black-tailed deer (Odocoileus hemionus sitkensis on Prince of Wales Island, Alaska. We used data collected through interviews with local deer hunters and GIS analysis of land cover to determine relationships among landscape change, hunter access, and habitat for deer hunting over the last 50 yr. We then used these relationships to predict how harvest opportunities may change in the future. Intensive logging from 1950 into the 1990s provided better access to deer and habitat that facilitated deer hunting. However, successional changes in intensively logged forests in combination with a decline in current logging activity have reduced access to deer and increased undesirable habitat for deer hunting. In this new landscape, harvest opportunities in previously logged landscapes have declined, and hunters identify second-growth forest as one of the least popular habitats for hunting. Given the current state of the logging industry in Alaska, it is unlikely that the logging of the remaining old-growth forests or intensive management of second-growth forests will cause hunter opportunities to rebound to historic levels. Instead, hunter opportunities may continue to decline for at least another human generation, even if the long-term impacts of logging activity and deer harvest on deer numbers are minimal. Adapting hunting strategies to focus on naturally open habitats such as alpine and muskeg that are less influenced by external market forces may require considerably more hunting effort but provide the best option for

  11. Joint Inversion of Geochemical Data and Geophysical Logs for Lithology Identification in CCSD Main Hole

    Science.gov (United States)

    Deng, Chengxiang; Pan, Heping; Luo, Miao

    2017-12-01

    The Chinese Continental Scientific Drilling (CCSD) main hole is located in the Sulu ultrahigh-pressure metamorphic (UHPM) belt, providing significant opportunities for studying the metamorphic strata structure, kinetics process and tectonic evolution. Lithology identification is the primary and crucial stage for above geoscientific researches. To release the burden of log analyst and improve the efficiency of lithology interpretation, many algorithms have been developed to automate the process of lithology prediction. While traditional statistical techniques, such as discriminant analysis and K-nearest neighbors classifier, are incompetent in extracting nonlinear features of metamorphic rocks from complex geophysical log data; artificial intelligence algorithms are capable of solving nonlinear problems, but most of the algorithms suffer from tuning parameters to be global optimum to establish model rather than local optimum, and also encounter challenges in making the balance between training accuracy and generalization ability. Optimization methods have been applied extensively in the inversion of reservoir parameters of sedimentary formations using well logs. However, it is difficult to obtain accurate solution from the logging response equations of optimization method because of the strong overlapping of nonstationary log signals when applied in metamorphic formations. As oxide contents of each kinds of metamorphic rocks are relatively less overlapping, this study explores an approach, set in a metamorphic formation model and using the Broyden Fletcher Goldfarb Shanno (BFGS) optimization algorithm to identify lithology from oxide data. We first incorporate 11 geophysical logs and lab-collected geochemical data of 47 core samples to construct oxide profile of CCSD main hole by using backwards stepwise multiple regression method, which eliminates irrelevant input logs step by step for higher statistical significance and accuracy. Then we establish oxide response

  12. Log-concavity property for some well-known distributions

    Directory of Open Access Journals (Sweden)

    G. R. Mohtashami Borzadaran

    2011-12-01

    Full Text Available Interesting properties and propositions, in many branches of science such as economics have been obtained according to the property of cumulative distribution function of a random variable as a concave function. Caplin and Nalebuff (1988,1989, Bagnoli and Khanna (1989 and Bagnoli and Bergstrom (1989 , 1989, 2005 have discussed the log-concavity property of probability distributions and their applications, especially in economics. Log-concavity concerns twice differentiable real-valued function g whose domain is an interval on extended real line. g as a function is said to be log-concave on the interval (a,b if the function ln(g is a concave function on (a,b. Log-concavity of g on (a,b is equivalent to g'/g being monotone decreasing on (a,b or (ln(g" 6] have obtained log-concavity for distributions such as normal, logistic, extreme-value, exponential, Laplace, Weibull, power function, uniform, gamma, beta, Pareto, log-normal, Student's t, Cauchy and F distributions. We have discussed and introduced the continuous versions of the Pearson family, also found the log-concavity for this family in general cases, and then obtained the log-concavity property for each distribution that is a member of Pearson family. For the Burr family these cases have been calculated, even for each distribution that belongs to Burr family. Also, log-concavity results for distributions such as generalized gamma distributions, Feller-Pareto distributions, generalized Inverse Gaussian distributions and generalized Log-normal distributions have been obtained.

  13. Les terrains jurassiques du sondage de Couy (Cher, France. Leur analyse séquentielle détaillée à partir de la description des carottes et des courbes diagraphiques Jurassic Formations in the Couy Borehole (Cher Department, France. Their Detailed Sequential Analysis from the Core Sample Descriptions and Well-Logging Curves

    Directory of Open Access Journals (Sweden)

    Gely J. P.

    2006-11-01

    (Lorenz et al. , 1987 make this borehole a first-rate stratigraphic reference concerning the Lower and Middle Jurassic series in the southern part of the Paris Basin. The lithostratigraphic analysis has already been the subject of a publication (Lorenz et al. , 1992, and a description of the sequences has been sketched out (Gely and Lorenz, 1991. At the same time, the implementation of lithostratigraphic data and the description of the well logs provide greater accuracy in interpretation in terms of desposit sequences, while the stratigraphic calibration of the well-log signatures gives a reference on the scale of the Paris Basin. The sequences defined in the Couy borehole are compared to the ones already published elsewhere on a global scale (Haq et al. , 1988; Vail et al. , 1987 and on a regional scale (Rioult et al. , 1991; Gonnin et al. , 1992, 1993; Bessereau and Guillocheau, 1994, (Figs. 2 and 3. Discontinuities corresponding to a sedimentation gap are usually represented by traces of bioturbation or by perforations in the top surface of a bed or else by a surface of gullying. In other cases, the sequence boundaries do not seem to be so clearly expressed but correspond to highly bioturbated bands, a single limestone bed in the midst of marls or perhaps an abrupt lithological change. For a limestone bed situated at the upper boundary of a sequence, we can see that this latter is often perforated or bioturbated. This enables them to be distinguished from other limestone levels situated at the transgressive maximum, and which contain pelagic fossils or authigenic minerals. On well logs, these two types of beds often have a comparable signature. The sequence boundaries are clearly shown by the well logs, which show clearcut curve breaks and are often capable of orienting or confirming the choice of identification criteria of the boundaries in the core samples. However, it can be seen that there is no direct relationships between the visible size of the discontinuity and

  14. Influence of logging on the effects of wildfire in Siberia

    Science.gov (United States)

    Kukavskaya, E. A.; Buryak, L. V.; Ivanova, G. A.; Conard, S. G.; Kalenskaya, O. P.; Zhila, S. V.; McRae, D. J.

    2013-12-01

    The Russian boreal zone supports a huge terrestrial carbon pool. Moreover, it is a tremendous reservoir of wood products concentrated mainly in Siberia. The main natural disturbance in these forests is wildfire, which modifies the carbon budget and has potentially important climate feedbacks. In addition, both legal and illegal logging increase landscape complexity and affect burning conditions and fuel consumption. We investigated 100 individual sites with different histories of logging and fire on a total of 23 study areas in three different regions of Siberia to evaluate the impacts of fire and logging on fuel loads, carbon emissions, and tree regeneration in pine and larch forests. We found large variations of fire and logging effects among regions depending on growing conditions and type of logging activity. Logged areas in the Angara region had the highest surface and ground fuel loads (up to 135 t ha-1), mainly due to logging debris. This resulted in high carbon emissions where fires occurred on logged sites (up to 41 tC ha-1). The Shushenskoe/Minusinsk and Zabaikal regions are characterized by better slash removal and a smaller amount of carbon emitted to the atmosphere during fires. Illegal logging, which is widespread in the Zabaikal region, resulted in an increase in fire hazard and higher carbon emissions than legal logging. The highest fuel loads (on average 108 t ha-1) and carbon emissions (18-28 tC ha-1) in the Zabaikal region are on repeatedly burned unlogged sites where trees fell on the ground following the first fire event. Partial logging in the Shushenskoe/Minusinsk region has insufficient impact on stand density, tree mortality, and other forest conditions to substantially increase fire hazard or affect carbon stocks. Repeated fires on logged sites resulted in insufficient tree regeneration and transformation of forest to grasslands. We conclude that negative impacts of fire and logging on air quality, the carbon cycle, and ecosystem

  15. Log-normal censored regression model detecting prognostic factors in gastric cancer: a study of 3018 cases.

    Science.gov (United States)

    Wang, Bin-Bin; Liu, Cai-Gang; Lu, Ping; Latengbaolide, A; Lu, Yang

    2011-06-21

    To investigate the efficiency of Cox proportional hazard model in detecting prognostic factors for gastric cancer. We used the log-normal regression model to evaluate prognostic factors in gastric cancer and compared it with the Cox model. Three thousand and eighteen gastric cancer patients who received a gastrectomy between 1980 and 2004 were retrospectively evaluated. Clinic-pathological factors were included in a log-normal model as well as Cox model. The akaike information criterion (AIC) was employed to compare the efficiency of both models. Univariate analysis indicated that age at diagnosis, past history, cancer location, distant metastasis status, surgical curative degree, combined other organ resection, Borrmann type, Lauren's classification, pT stage, total dissected nodes and pN stage were prognostic factors in both log-normal and Cox models. In the final multivariate model, age at diagnosis, past history, surgical curative degree, Borrmann type, Lauren's classification, pT stage, and pN stage were significant prognostic factors in both log-normal and Cox models. However, cancer location, distant metastasis status, and histology types were found to be significant prognostic factors in log-normal results alone. According to AIC, the log-normal model performed better than the Cox proportional hazard model (AIC value: 2534.72 vs 1693.56). It is suggested that the log-normal regression model can be a useful statistical model to evaluate prognostic factors instead of the Cox proportional hazard model.

  16. Selective‐logging and oil palm: multitaxon impacts, biodiversity indicators, and trade‐offs for conservation planning.

    Science.gov (United States)

    Edwards, David P; Magrach, Ainhoa; Woodcock, Paul; Ji, Yinqiu; Lim, Norman T -L; Edwards, Felicity A; Larsen, Trond H; Hsu, Wayne W; Benedick, Suzan; Khen, Chey Vun; Chung, Arthur Y C; Reynolds, Glen; Fisher, Brendan; Laurance, William F; Wilcove, David S; Hamer, Keith C; Yu, Douglas W

    Strong global demand for tropical timber and agricultural products has driven large-scale logging and subsequent conversion of tropical forests. Given that the majority of tropical landscapes have been or will likely be logged, the protection of biodiversity within tropical forests thus depends on whether species can persist in these economically exploited lands, and if species cannot persist, whether we can protect enough primary forest from logging and conversion. However, our knowledge of the impact of logging and conversion on biodiversity is limited to a few taxa, often sampled in different locations with complex land-use histories, hampering attempts to plan cost-effective conservation strategies and to draw conclusions across taxa. Spanning a land-use gradient of primary forest, once- and twice-logged forests, and oil palm plantations, we used traditional sampling and DNA metabarcoding to compile an extensive data set in Sabah, Malaysian Borneo for nine vertebrate and invertebrate taxa to quantify the biological impacts of logging and oil palm, develop cost-effective methods of protecting biodiversity, and examine whether there is congruence in response among taxa. Logged forests retained high species richness, including, on average, 70% of species found in primary forest. In contrast, conversion to oil palm dramatically reduces species richness, with significantly fewer primary-forest species than found on logged forest transects for seven taxa. Using a systematic conservation planning analysis, we show that efficient protection of primary-forest species is achieved with land portfolios that include a large proportion of logged-forest plots. Protecting logged forests is thus a cost-effective method of protecting an ecologically and taxonomically diverse range of species, particularly when conservation budgets are limited. Six indicator groups (birds, leaf-litter ants, beetles, aerial hymenopterans, flies, and true bugs) proved to be consistently good

  17. LOG FILE ANALYSIS AND CREATION OF MORE INTELLIGENT WEB SITES

    OpenAIRE

    Šimunić, Mislav; Hutinski, Željko; Čubrilo, Mirko

    2005-01-01

    To enable successful performance of any company or business system, both in the world and in the Republic of Croatia, among any problems relating to its operations and particularly to maximum utilization and efficiency of the Internet as a media for running business (especially in terms of marketing), they should make the best possible use of the present-day global trends and advantages of sophisticated technologies and approaches to running a business. Bearing in mind the fact of daily incre...

  18. The ACGME Case Log System May Not Accurately Represent Operative Experience Among General Surgery Interns.

    Science.gov (United States)

    Naik, Nimesh D; Abbott, Eduardo F; Aho, Johnathon M; Pandian, T K; Thiels, Cornelius A; Heller, Stephanie F; Farley, David R

    To assess if the Accreditation Council for Graduate Medical Education (ACGME) case log system accurately captures operative experience of our postgraduate year 1 (PGY-1) residents. ACGME case log information was retrospectively obtained for 5 cohorts of PGY-1 residents (2011-2015) and compared to the number of operative cases captured by an institutional automated operative case report system, Surgical Access Utility System (SAUS). SAUS automatically captures all surgical team members who are listed in the operative dictation for a given case, including interns. A paired t-test analysis was used to compare number of cases coded between the 2 systems. Academic, tertiary care referral center with a large general surgery training program. PGY-1 general surgery trainees (interns) from the years 2011-2015. Forty-nine PGY-1 general surgery residents were identified over a 5-year period. Mean operative case volume per intern, per year, captured by the automated SAUS was 176.5 ± 28.1 (SD) compared to 126.3 ± 58.0 ACGME cases logged (mean difference = 50.2 cases, p log data may not accurately reflect the actual operative experience of our PGY-1 residents. If such data holds true for other general surgery training programs, the true impact of duty hour regulations on operative volume may be unclear when using the ACGME case log data. This current standard approach for using ACGME case logs as a representation of operative experience requires further scrutiny and potential revision to more accurately determine operative experience for accreditation purposes. Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  19. Analyzing engagement in a web-based intervention platform through visualizing log-data.

    Science.gov (United States)

    Morrison, Cecily; Doherty, Gavin

    2014-11-13

    Engagement has emerged as a significant cross-cutting concern within the development of Web-based interventions. There have been calls to institute a more rigorous approach to the design of Web-based interventions, to increase both the quantity and quality of engagement. One approach would be to use log-data to better understand the process of engagement and patterns of use. However, an important challenge lies in organizing log-data for productive analysis. Our aim was to conduct an initial exploration of the use of visualizations of log-data to enhance understanding of engagement with Web-based interventions. We applied exploratory sequential data analysis to highlight sequential aspects of the log data, such as time or module number, to provide insights into engagement. After applying a number of processing steps, a range of visualizations were generated from the log-data. We then examined the usefulness of these visualizations for understanding the engagement of individual users and the engagement of cohorts of users. The visualizations created are illustrated with two datasets drawn from studies using the SilverCloud Platform: (1) a small, detailed dataset with interviews (n=19) and (2) a large dataset (n=326) with 44,838 logged events. We present four exploratory visualizations of user engagement with a Web-based intervention, including Navigation Graph, Stripe Graph, Start-Finish Graph, and Next Action Heat Map. The first represents individual usage and the last three, specific aspects of cohort usage. We provide examples of each with a discussion of salient features. Log-data analysis through data visualization is an alternative way of exploring user engagement with Web-based interventions, which can yield different insights than more commonly used summative measures. We describe how understanding the process of engagement through visualizations can support the development and evaluation of Web-based interventions. Specifically, we show how visualizations

  20. Differences in Prokaryotic Species Between Primary and Logged-Over Deep Peat Forest in Sarawak, Malaysia

    International Nuclear Information System (INIS)

    Mohd Shawal Thakib Maidin; Sakinah Safari; Nur Aziemah Ghani; Sharifah Azura Syed Ibrahim; Shamsilawani Ahamed Bakeri; Mohamed Mazmira Mohd Masri; Siti Ramlah Ahmad Ali

    2016-01-01

    Peat land has an important role in environmental sustainability which can be used for agricultural purposes. However, deforestation in the logged-over forest may disrupt the diversity of microbial population in peat soil. Therefore, this study focuses on the differences of microbial populations in Maludam primary forest and Cermat Ceria logged-over forest in Sarawak, Malaysia. The prokaryotic 16S rDNA region was amplified followed by denaturing gradient gel electrophoresis (16S PCR-DGGE) analysis. Berger-Parker and Shannon-Weaver Biodiversity Index showed that Maludam (0.11, 7.75) was more diverse compared to Cermat Ceria (0.19, 7.63). Sequence analysis showed that the bacterial community in Maludam and Cermat Ceria were dominated by unclassified bacteria, followed by Acidobacteria, Actinobacteria, Firmicutes and a-Proteobacteria. Based on the findings, the distinct species that can be found in Maludam were Acidobacterium capsulatum, Solibacter sp., Mycobacterium intracellulare, Rhodoplanes sp., Clostridia bacterium, Exiguobacterium sp. and Lysinibacillus fusiformis. While, the distinct species that can be found in Cermat Ceria were Telmatobacter, Mycobacterium tuberculosis and Bacillus tequilensis. Overall, the findings showed that microbial population in the logged-over forest are less diverse compared to primary forest. Higher prokaryotic diversity identified in the primary forest compared to logged-over forest showed that deforestation might cause prokaryotic population changes to both ecosystems. (author)