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Auswahl der wissenschaftlichen Literatur zum Thema „Number of logging tools“
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Zeitschriftenartikel zum Thema "Number of logging tools"
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Suhartana, Sona, and Yuniawati Yuniawati. "ANALYSIS OF USING EFFICIENT LOGGING TOOLS AT PT. PURWA PERMAI IN CENTRAL KALIMANTAN." JOURNAL OF FORESTRY RESEARCH 5, no. 1 (2008): 53–64. https://doi.org/10.20886/ijfr.2008.5.1.53-64.
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A high log demand that often exceeds its supply capability should be overcome by using appropriate logging tools. Numerous kinds and types of logging tools require a well planning in their utilization. Number of tools which are greater or fewer than what is actually needed can be disadvantageous for a company. In relevant to these aspects, a study was carried out at a timber estate in Central Kalimantan in 2007. The aim of the study was to find out an efficient number of tools used for logging in a timber estate. The analysis was based on the target and realization of the company’s log production. The result revealed that: (1) Optimum number of logging tools depended on production target, i.e. 41 units of chainsaws for felling, 42 units of farm tractors for skidding, 9 units of loaders for loading and unloading, and 36 units of trucks for transportation; (2) Number of logging tools as obtained from all activities in the field was fewer than that from the analysis based on production target and realization. This condition indicated that number of logging tools used in the company was not yet efficient.
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Ji, Yongli, Zhiqiang Li, Jigen Xia, and Jiajia Song. "A standard calibration method based on a symmetric resistance network matrix for galvanic logging instruments." PLOS ONE 19, no. 4 (2024): e0302032. http://dx.doi.org/10.1371/journal.pone.0302032.
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An increasing number of measurement electrodes have been designed to satisfy the demand for high-resolution detection using galvanic logging technology in complex formations. The forward modeling response analysis of logging tools has important guiding significance in the design of galvanic logging tools. Based on a three-dimensional finite element numerical simulation method, we established a forward model of galvanic multi-electrodes in a complex formation. We also designed a symmetrical resistance network model of the formation with equivalent resistance between two electrodes. A symmetrical resistance network was derived using the balanced bridge method. The asymmetrical admittance matrix was extended to a symmetrical extended admittance matrix to realize a convenient calculation of the equivalent symmetrical resistance network in complex formations. Verification of the microcolumn-focused logging tool, with nine electrodes in a simulated standard well, and an evaluation of the degree of invasion in an actual oil well indicate that this calibration method can improve the measurement accuracy of galvanic logging instruments.
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Gu, Caiyun, Peng Zhao, Li Wang, and Hongxia Guo. "Technical Application of Petroleum Logging Instruments in Marine Logging." Polish Maritime Research 25, s3 (2018): 22–28. http://dx.doi.org/10.2478/pomr-2018-0108.
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Abstract To solve the problem of offshore oilfield development, based on the newly introduced pulsed neutron oxygen activation logging instrument, the application research of test design and interpretation method was carried out and applied to actual production. The structure, technical indicators and logging principles of pulsed neutron oxygen activation logging tools were introduced. The test design under different well conditions was studied, including general positive and negative injection, oil sleeve injection, single oil pipe configuration and multitubing configuration. A large amount of field test data was collected and analysed technically. A set of effective interpretation models was proposed. The corresponding interpretation software was developed. A set of test design methods and operating specifications for different well conditions were developed. Based on the conventional interpretation method, the peak selection, the double-tuber peak identification and the carbon dioxide flooding interpretation method were added. The results show that the test design and interpretation methods were applied well through a large number of field tests and production applications. Therefore, pulsed neutron oxygen activated injection profile logging technology is successfully applied in offshore oil fields.
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Tagiev, Mikail. "Shadow Economy Forms of Manifestation and Tools to Combat it in the Timber Industry." Bulletin of Baikal State University 28, no. 4 (2018): 711–18. http://dx.doi.org/10.17150/2500-2759.2018.28(4).711-718.
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The article presents the structure of illegal logging activity, and differentiates its informal and criminal components. The legislative measures taken by the state to curb illegal felling and logging are analyzed. To create a general representation of the size of the shadow economy in the timber industry, the author structures the main forms of its manifestation, which allows him to classify the factors of the shadow economy in the industry and recommend a set of measures aimed at minimizing the size of the shadow economy activities. The author also examines the dynamics of the informal sector in Russia (the number of people employed in this sector, the amount of income received) and the example of the Irkutsk region. The author describes the mechanisms of state regulation of illegal logging in the region through the legal, power, economic, conventional and cultural-normative approach. In conclusion, the author proposes specific measures to minimize the level of the shadow economy in the logging industry of the Irkutsk region.
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Prammer, M. G., J. Bouton, E. D. Drack, M. N. Miller, and R. N. Chandler. "A New Multiband Generation of NMR Logging Tools." SPE Reservoir Evaluation & Engineering 4, no. 01 (2001): 59–63. http://dx.doi.org/10.2118/69670-pa.
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Summary This paper describes the hardware and operation of a new generation of nuclear magnetic resonance (NMR) logging tools. In the past, NMR required the logging engineer to consider the T1 relaxation times of the reservoir fluids likely to be encountered. Actual, or simply assumed, long T1's translated into slow logging speeds. The new tool generation overcomes this limitation. The key feature is that nine sensitive volumes are polarized in parallel and are read out in rapid sequence. A new sonde design speeds up the polarization process by a factor of 2. Each volume contributes equally to the result and can support identical measurements for rapid stacking and fast logging, and each can be used for individual, simultaneous measurements. Laboratory data and field-test results are presented to demonstrate both the relative simplicity of operation and the improvement in data quality. Logging speeds typically can be upgraded by a factor of 4, while data for total porosity determination and fluid typing are acquired in a single logging pass. Background Over the past few years, log analysts have become familiar with the potential and the limitations of NMR logging. Basically, an NMR tool reports the total number of hydrogen atoms that are in the liquid or gaseous state. As such, NMR is a lithology-independent porosity tool as long as the hydrogen index of the fluids can be estimated. The commercial use of modern pulsed-NMR tools (NUMAR's MRIL1,***, and Schlumberger's CMR,2,**** brought two surprises:The near-borehole zone, which was assumed to be flushed, can contain substantial amounts of native hydrocarbons, both oil and gas.The T1 relaxation times of hydrocarbons (connate fluids and filtrate from oil-based muds) under reservoir conditions are substantially longer than previously assumed. The consequence of these findings was that NMR began to be used as a hydrocarbon-detection and reservoir-quantification tool, at the expense of logging speed and wellsite efficiency.3,4 From the theory of nuclear spin relaxation in liquids by Bloembergen, Purcell, and Pound5 follows the proportionality of bulk relaxation time and self-diffusion coefficient: T1~D. The Stokes relationship between viscosity and correlation time stipulates that D~T/µ; therefore, we can expect that T1~T/µ over a certain range of temperatures. We conducted measurements of T1 and T2 in the 30 to 150°C range on oils used for oil-based mud synthesis.***** Some of our results are listed in Table 1. These oils are typically type C16/C18, with hydrogen indices close to that of water. The absence of longer chains or aromatics suggests short correlation times and long T1 relaxation times for Larmor frequencies in the low-MHz range. For all samples investigated, T1=T2. In general, our data confirm the expected temperature dependency of T1. Certain oils, however, including Oil B and Oil C in Table 1, show a sharp discontinuity at some point between 110 and 150°C. We have confirmed that no chemical change takes place in the oil because the original T1 can be restored by cooling the sample to room temperature and exposing it to the atmosphere. The most likely explanation is dissolved oxygen that becomes volatile above 110°C. Paramagnetic oxygen is a potent relaxation agent even at low concentrations, and its disappearance at high temperatures causes an additional increase in T1. The surface interaction, which is responsible for rapid relaxation/polarization in the water phase, is inefficient for oil, even in cases where rock analysis would classify the rock as oil-wet. Gas is another example of high T1's (4-5 sec and more) caused by weak internal relaxation and nonexistent interaction with the rock surface. T 1 affects data acquisition and logging speed in a direct fashion:The hydrogen atoms must be exposed to the polarizing magnetic field for a multiple of T1. A factor of 3 is considered minimum. Fig. 1 illustrates exponential polarization curves for T1's of 1 sec, 2 sec, and 4 sec. Note that 95% polarization is reached only after 12 sec for fluids with T1=4 sec.The measurement itself is contaminated by thermal noise and must be repeated a few times to bring the influence of this noise down to acceptable levels. After each measurement, a full wait time (tw) of at least 3× T1 is required. Assuming 8 repeats and T1=4 sec, we find that the wait times required for a single measurement add up to 8×4×3=96 sec. If a vertical resolution of 3 ft is acceptable, the NMR tool cannot move faster than 3×60/96˜2 ft/min. A speed limit of 120 ft/hr makes it impractical to deploy NMR on a routine basis over large openhole intervals. An undesirable option is to forego full polarization. This mode is faster but results in data that are substantially harder to interpret in a quantitative fashion. Furthermore, this mode defeats the unique capability of NMR to detect hydrocarbons independent of resistivity contrast. It is highly desirable to use an NMR tool that is virtually free of T1 effects. Current NMR applications such as total and effective porosities, pore-size distribution, permeability modeling, hydrocarbon typing, and gas detection require that all hydrogen components are equally visible; i.e., even the slowest T1 component should be fully polarized. Furthermore, these applications should run at logging speeds of 1,000-1,500 ft/hr. Lastly, a higher level of automation should reduce the amount of job planning and setup procedures required today. These requirements are met by the newest generation of MRIL tools, MRIL-Prime. The T1 problem is solved by using a large number of measurement volumes in parallel and by employing a new prepolarization scheme. New Tool Features The key feature of the new MRIL tool is the ability to rapidly polarize and to read out many identical measurement volumes. The scheme is illustrated in Fig. 2. There are nine tightly packed cylindrical shells, each 24 in. tall and each containing on average 750 mL. The tool electronics can rapidly switch back and forth between volumes by changing the operating frequency over a wide range. The magnetic field gradient translates lower operating frequencies into resonance conditions that occur farther away from the tool. The gradient is circularly symmetric, resulting in resonance shells around the tool. These shells are labeled A (innermost, diameter 14 in.) to J (outermost, diameter 16.5 in.). In an 8-in. borehole, these diameters correspond to a depth of investigation between 3 and 4 in. The individual volumes are completely separated such that concurrent measurements do not influence each other. The approximate field strength, resonance frequency, and magnetic field gradient for each measurement volume is listed in Table 2.
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Ashok, Lama. "Monitoring and Logging Best Practices in Java Microservices for Effective Software Development." International Journal of Computer Application 15, no. 2 (2025): 4–9. https://doi.org/10.5281/zenodo.15362493.
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<strong>Abstract</strong> In the era of microservices architecture, effective monitoring and log The complexity of administering and observing these systems increases with the distribution of applications, so it is crucial to have strong monitoring and logging procedures in place. Best practices for Java microservices monitoring and logging are examined in this article, with a focus on the value of real-time insights into application activity, performance indicators, and error tracking. Effective monitoring and logging are made possible by a number of tools and frameworks, including Prometheus, Grafana, and ELK Stack. We also go over how to incorporate these techniques into the software development lifecycle. Additionally, We emphasize how important distributed tracing and structured logging are for improving observability across microservices. Organizations may improve system dependability, proactively detect and fix problems, and improve overall software quality by implementing thorough monitoring and logging procedures. These actions will ultimately improve user experience and boost operational efficiency. <strong>Keywords</strong> Java, Microservices, Monitoring, Logging, Spring Boot, Observability, ELK Stack, Prometheus, Grafana, Distributed Tracing
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Pine, John C., Brian D. Marx, and Cornelis F. de Hoop. "Characteristics of Workers' Compensation Injuries for Logging Operations in Louisiana: 1985-1990." Southern Journal of Applied Forestry 18, no. 3 (1994): 110–15. http://dx.doi.org/10.1093/sjaf/18.3.110.
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Abstract The number of reported workers' compensation injuries in logging operations in Louisiana has decreased at a time when the number of employees in logging has increased. Employees with less than 3 yr of employment accounted for 82% of all claims. The percentage of cases involving cuts and lacerations decreased from 1985 through 1990; however, sprains and strains increased, from 15% in 1985 to 28% in 1990, during this period. Back injuries accounted for 15% of injuries. Falls contributed to 13% of injuries. Falling trees were the major cause of fatalities. Truck drivers were 20% of the claimants. Workers who were struck by or against trees or logs resulted in a major cause of lost time injuries to employees, as well as in juries from the use of hand tools, which have decreased, from 25% in 1987 to 13% in 1990. The lower extremities are most vulnerable to injuries in logging operations. Workers' compensation injuries and cost continues to be a major concern for those involved in logging operations, even though the frequency and rate of cases decreased from 1985 to 1990. South. J. Appl. For. 18(3): 110-115.
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Bradley, Tom, Simon Austin, David Holbrough, et al. "A Universal Data Format for Wellbore Logs." Petrophysics – The SPWLA Journal of Formation Evaluation and Reservoir Description 64, no. 6 (2023): 823–36. http://dx.doi.org/10.30632/pjv64n6-2023a1.
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This paper describes a proposed high-specification standard format that is ideally suited for the data management of definitive records of wellbore logs. For this reason, it is a good standard for data exchange between applications. The format is suitable for complex three-dimensional (3D) data, including those generated by deep azimuthal resistivity (DAR) and ultradeep azimuthal resistivity (UDAR) tools, acoustic borehole reflection images, vertical seismic profiles (VSP), borehole imaging tools, multifingered caliper logs, and array data with multiple depths of investigation. It is applicable for use with logging-while-drilling (LWD) and wireline-conveyed logging tools. The format also naturally collapses down when utilized to store simple conventional logs that contain one value per depth in the wellbore. The proposed format provides spatial details of every data point collected by or interpreted from a wellbore-logging tool. The position of each data point is defined by reference back to the measure point of the sonde, which in turn is defined by the wellbore deviation survey and its coordinate reference system (CRS). Each data point in space may have an unrestricted number of parameters. An example might be most likely horizontal and vertical resistivity, maximum value based on uncertainty, minimum value based on uncertainty, and flags indicating the data position with respect to depth of detection (DOD). The new proposed format is so versatile. It is suitable as an Open Group Open Subsurface Data UniverseTM (OSDUTM) standard to store and exchange all data measured by logging tools in a wellbore and can possibly be extended to include all well data (for example, core, cuttings, and more). The proposed format requires a detailed definition so that computer scientists can implement it in applications used for subsurface modeling. The OSDU will also require this detailed definition in order to adopt it as a standard.
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Skakalska, L. V., A. V. Nazarevych, and V. I. Kosarchyn. "THE THEORETICAL-EMPIRICAL TECHNIQUE OF HYDROCARBONS PREDICTION IN THE BOREHOLES LOGS WITH THE BASIC PARAMETER – COMPRESSIBILITY." Мінеральні ресурси України, no. 4 (December 28, 2018): 18–25. http://dx.doi.org/10.31996/mru.2018.4.18-25.
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The theoretical-empirical technique of hydrocarbon prediction in the boreholes logs is presented. It is based on the adequate physical-mathematical model of rocks, on the empirical relations between compressibility, porosity and pressure for these rocks, on the core data and also on acoustic logging data (the interval times or body wave’s velocities). For the cases of the acoustic logging data absence, the variants of the prediction technique by using data of gamma-logging, electric logging, and the offset logging method are developed. The presented technique is realized as a system of theoretical and empirical relations and the resulting functional. The adequate set of software tools is developed in the Fortran, C# and Excel environments. The technique is tested on the well’s data of a number of structures of Western oil and gas region of Ukraine: Lishchynska, Buchatska, Ludynska, Zaluzhanska, Zarichnianska, Nyklovytska, Orkhovytska. The statistical estimations of petrophysical characteristics of rock-collectors of those wells are presented. For more reliable prediction by the technique, instead of relations for the general parametric base, the empirical relations for concrete available in the studied boreholes logs types and subtypes of rock-collectors are elaborated.
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Mokhirev, Aleskandr P., Sergey Yu Rezinkin, Sergey O. Medvedev, and Nataliya A. Bragina. "USE OF GEOGRAPHIC INFORMATION SYSTEMS IN THE EVALUATION OF THE DENSITY OF ROADS OF FORESTRY AREAS." Vestnik SSUGT (Siberian State University of Geosystems and Technologies) 25, no. 3 (2020): 181–91. http://dx.doi.org/10.33764/2411-1759-2020-25-3-181-191.
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In Russia, the density of forest roads is significantly lower than in countries with developed forest industries. This negatively affects the efficiency of logging and the yield of wood per unit area. There are different opinions about the normative and actual values of the density of forest roads in the forest regions of Russia. Today, it is possible to assess the density of forest roads and analyze its development using modern geographic information systems (GIS). In these studies, the density of forest roads is determined using the ArcGis software package in the two forest districts of Krasnoyarsk Territory. The roads located on the territory of the studied sections are digitized and divided by types: highway of year-round operation, branch, logging mustache. Using the tools of the software package, the lengths and densities of roads are determined by their types. The obtained values are consistent with the indicators of other researchers from different regions of Russia. The results of this task are necessary for the planning of logging production when searching for optimal routes for wood delivery, taking into account the natural and climatic conditions. Using ArcGIS tools allowed us to automate a significant number of calculations in the study and, in particular, calculate the density of roads, visualize the data obtained, and also form the basis for further research.
Dissertationen zum Thema "Number of logging tools"
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Hue, Yik-Kiong. "Analysis of electromagnetic well-logging tools." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1143053776.
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Pulls, Tobias. "Preserving Privacy in Transparency Logging." Doctoral thesis, Karlstads universitet, Institutionen för matematik och datavetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-35918.
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The subject of this dissertation is the construction of privacy-enhancing technologies (PETs) for transparency logging, a technology at the intersection of privacy, transparency, and accountability. Transparency logging facilitates the transportation of data from service providers to users of services and is therefore a key enabler for ex-post transparency-enhancing tools (TETs). Ex-post transparency provides information to users about how their personal data have been processed by service providers, and is a prerequisite for accountability: you cannot hold a controller accountable for what is unknown. We present three generations of PETs for transparency logging to which we contributed. We start with early work that defined the setting as a foundation and build upon it to increase both the privacy protections and the utility of the data sent through transparency logging. Our contributions include the first provably secure privacy-preserving transparency logging scheme and a forward-secure append-only persistent authenticated data structure tailored to the transparency logging setting. Applications of our work range from notifications and deriving data disclosures for the Data Track tool (an ex-post TET) to secure evidence storage.<br>The subject of this dissertation is the construction of privacy-enhancing technologies (PETs) for transparency logging, a technology at the intersection of privacy, transparency, and accountability. Transparency logging facilitates the transportation of data from service providers to users of services and is therefore a key enabler for ex-post transparency-enhancing tools (TETs). Ex-post transparency provides information to users about how their personal data have been processed by service providers, and is a prerequisite for accountability: you cannot hold a controller accountable for what is unknown. We present three generations of PETs for transparency logging to which we contributed. We start with early work that defined the setting as a foundation and build upon it to increase both the privacy protections and the utility of the data sent through transparency logging. Our contributions include the first provably secure privacy-preserving transparency logging scheme and a forward-secure append-only persistent authenticated data structure tailored to the transparency logging setting. Applications of our work range from notifications and deriving data disclosures for the Data Track tool (an ex-post TET) to secure evidence storage.
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NOVO, MARCELA SILVA. "NUMERICAL ANALYSIS OF ELECTROMAGNETIC WELL-LOGGING TOOLS BY USING FINITE VOLUME METHODS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=11478@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO<br>COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR<br>SOCIETY OF EXPLORATION GEOPHYSICISTS FOUNDATION<br>SOCIETY OF PETROPHYSICISTS & WELL LOG ANALYSTS<br>O objetivo principal deste trabalho é o desenvolvimento
de
modelos computacionais para analisar a resposta
eletromagnética de ferramentas de perfilagem LWD/MWD em
formações geofísicas arbitrárias. Essa modelagem
envolve a determinação precisa de campos eletromagnéticos
em regiões tridimensionais (3D) complexas e,
conseqüentemente, a solução de sistemas lineares
não-hermitianos de larga escala. A modelagem numérica é
realizada através da aplicação do método dos volumes
finitos (FVM) no domínio da
freqüência. Desenvolvem-se dois modelos computacionais, o
primeiro válido
em regiões isotrópicas e o segundo considerando a
presença
de anisotropias
no meio. As equações de Maxwell são resolvidas através de
duas formulações
distintas: formulação por campos e formulação por
potenciais vetor e escalar. A discretização por volumes
finitos utiliza um esquema de grades
entrelaçadas em coordenadas cilíndricas para evitar erros
de aproximação de escada da geometria da ferramenta. Os
modelos desenvolvidos incorporam quatro técnicas
numéricas
para aumentar a eficiência computacional e a precisão do
método. As formulações por campos e por potenciais vetor
e escalar são comparadas em termos da taxa de
convergência
e do tempo de processamento em cenários tridimensionais.
Os
modelos foram validados e testados em cenários
tridimensionais complexos, tais como: (i) poços
horizontais ou direcionais; (ii) formações não homogêneas
com invasões de fluído de perfuração; (iii) formações
anisotrópicas e (iv) poços excêntricos.
Motivado pela flexibilidade dos modelos e pelos
resultados
numéricos obtidos em diferentes cenários tridimensionais,
estende-se a metodologia para analisar a resposta de
ferramentas LWD que empregam antenas inclinadas
em relação ao eixo da ferramenta. Tais ferramentas podem
prover dados com sensibilidade azimutal, assim como
estimativas da anisotropia da formação,
auxiliando o geodirecionamento de poços direcionais e
horizontais.<br>The main objective of this work is to develop computational
models to
analyze electromagnetic logging-while-drilling tool
response in arbitrary
geophysical formations. This modeling requires the
determination of electromagnetic fields in three-
dimensional (3-D) complex regions and consequently, the
solution of large scale non-hermitian systems. The numerical
modeling is done by using Finite Volume Methods (FVM) in
the frequency
domain. Both isotropic and anisotropic models are
developed. Maxwell's
equations are solved by using both the field formulation
and the coupled
vector-scalar potentials formulation. The proposed FVM
technique utilizes
an edge-based staggered-grid scheme in cylindrical
coordinates to avoid
staircasing errors on the tool geometry. Four numerical
techniques are incorporated in the models in order to
increase the computational efficiency
and the accuracy of the method. The field formulation and
the coupled vector-scalar potentials formulation are
compared in terms of their accuracy, convergence rate, and
CPU time for three-dimensional environments.
The models were validated and tested in 3-D complex
environments, such as:(i) horizontal and directional
boreholes; (ii) multilayered geophysical formations
including mud-filtrate invasions; (iii) anisotropic
formations and (iv)eccentric boreholes. The methodology is
extended to analyze LWD tools that are constructed with the
transmitters and/or receivers tilted with respect
to the axis of the drill collar. Such tools can provide
improved anisotropy measurements and azimuthal sensitivity
to benefit geosteering.
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ROSA, GUILHERME SIMON DA. "PSEUDO-ANALYTICAL MODELING FOR ELECTROMAGNETIC WELL-LOGGING TOOLS IN COMPLEX GEOPHYSICAL FORMATIONS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2017. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=30559@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO<br>COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR<br>CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO<br>PROGRAMA DE DOUTORADO SANDUÍCHE NO EXTERIOR<br>Esta tese apresenta um estudo sobre técnicas de modelagem numérica utilizadas na análise da propagação eletromagnética em formações geofísicas comumente encontradas na perfuração de poços de petróleo. O emprego de sensores eletromagnéticos adjacentes à broca de perfuração permite a inferência dos parâmetros constitutivos do solo ao redor do poço. Nos últimos anos, os avanços da tecnologia de perfilagem eletromagnética permitiram a modelagem em tempo real do problema, possibilitando direcionar a perfuração do poço a fim de maximizar a exploração de petróleo, gás, e outros hidrocarbonetos fósseis. Formações geofísicas complexas são predominantes neste tipo de problema, e geralmente são modeladas usando técnicas numéricas de força bruta como os métodos de diferenças finitas, dos elementos finitos ou dos volumes finitos. No entanto, estas técnicas têm um custo computacional relativamente alto em termos de memória e tempo de processamento. O avanço da tecnologia de perfilagem em tempo real requer
abordagens mais eficientes. Neste trabalho nós empregamos o método do casamento de modos combinado com uma série de características positivas dos métodos pseudoanalíticos conhecidos na literatura para obter uma técnica inédita que permite analisar poços direcionais com estratificações radiais e longitudinais em formações geofísicas anisotrópicas. A técnica proposta permite modelar problemas ainda não explorados, mas com motivação tecnológica iminente, como a propagação eletromagnética ao longo de poços curvados e a perfuração em camadas inclinadas em relação ao eixo axial do poço. Nós apresentamos uma série de resultados de validação que demonstram que a técnica introduzida neste trabalho pode modelar de forma acurada e eficiente sensores de perfilagem eletromagnética usados na exploração de petróleo e gás.<br>This research presents a study on numerical techniques to model the electromagnetic propagation in geophysical formations commonly encountered in oil well drilling. The employment of electromagnetic sensors surrounding the drill bit allows inferring the constitutive parameters of the soil around the well. In recent years, advances in electromagnetic logging technology have enabled the real-time modeling of this problem. In this way, the drilling direction can be guided in order to maximize the exploitation of oil, gas, and other fossil hydrocarbons. The complex geophysical formations that are prevalent in this type of problem can be effectively handled using brute-force numerical techniques such as finite-differences, finite-elements and finite-volumes. However, these techniques suffer from relatively high cost in terms of both computer memory and CPU time. The advancement of real-time logging technology demands approaches that are more efficient than purely numerical methods. In this work, we employ the mode-matching
technique combining attractive features of the well-known pseudo-analytical approaches to obtain a new technique for analyzing directional well-logging tools in anisotropic formations with both radial and axial stratifications. The proposed technique allows to model problems not yet explored, but with a strong technological motivation, such as electromagnetic propagation along curved wells and drilling along inclined layers. We present a series of validation results showing that the novel technique introduced in this study
can model accurately and efficiently electromagnetic logging sensors used in oil and gas exploration.
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Храпай, Р. Г. "Програмна модернізація зношеної системи координатних рухів для ЧПК верстату". Thesis, Сумський державний університет, 2018. http://essuir.sumdu.edu.ua/handle/123456789/67836.
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Дана робота присвячена підвищенню точності обробки заготовки на автоматизованих металооброблювальних центрах, які мають осі з механічно зношеними направляючими та шарово-гвинтовою парою, за допомогою програмної модернізації констант в системі SINUMERIC 840D. Не зважаючи на ряд обмежень та відсутності прямих параметрів для подібних дій, в системі присутні параметри, за правильної зміни яких таке стає можливим.
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Kuhlmann, Holmer. "Reconstruction of the sedimentary history offshore NW Africa application of core-logging tools /." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=975478648.
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7
Lee, Hwa Ok. "Cylindrical FDTD analysis of LWD tools through anisotropic dipping layered earth media." Connect to resource, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1146148166.
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Micheli, Gabrielle de. "Discrete Logarithm Cryptanalyses : Number Field Sieve and Lattice Tools for Side-Channel Attacks." Electronic Thesis or Diss., Université de Lorraine, 2021. http://www.theses.fr/2021LORR0104.
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Les cryptosystèmes dits à clé publique sont construits à l'aide de fonctions à sens unique qui assurent à la fois la sécurité et l'efficacité des cryptosystèmes. L'un des deux principaux candidats envisagés à l'origine pour construire de tels cryptosystèmes est l'exponentiation modulaire avec son opération inverse, le calcul de logarithmes discrets. Dans cette thèse, nous étudions la sécurité de protocoles qui utilisent des exponentiations modulaires où l'exposant est un secret du protocole. Afin d'évaluer la sécurité de tels protocoles, on peut d'une part estimer la difficulté de résoudre directement le problème du logarithme discret (DLP) dans les groupes considérés par les protocoles, ou examiner les vulnérabilités issues de l'implémentation des algorithmes d'exponentiation rapide. Une première façon d'estimer la sécurité des protocoles basés sur la difficulté du problème du logarithme discret est d'étudier directement la complexité des algorithmes qui résolvent ce dernier. Dans cette thèse, nous étudions la complexité asymptotique des algorithmes qui résolvent le DLP sur des corps finis « \F_{p^n} » précisément de la forme où les couplages prennent leurs valeurs. Nous proposons également une première implémentation et un calcul record d'un logarithme discret dans un corps fini de 521 bits en utilisant l'algorithme Tower Number Field Sieve, une variante de NFS dont la complexité asymptotique est meilleure. Cette variante n'avait jamais été implémentée auparavant en raison de la difficulté du crible algébrique dans des dimensions supérieures à deux. Enfin, la sécurité des protocoles déployés ne repose pas seulement sur la difficulté du problème mathématique sous-jacent, mais aussi sur l'implémentation des algorithmes considérés. De nombreux algorithmes d'exponentiation modulaire rapide se sont accumulés au fil des ans et certaines implémentations ont fait apparaître des vulnérabilités exploitables par des attaques par canaux auxiliaires. Un second aspect de cette thèse considère donc les principales méthodes pour reconstituer une clé secrète lorsque des informations partielles sont récupérées à partir d'un canal auxiliaire<br>Public-key cryptosystems are constructed using one-way functions which ensure both the security and the efficiency of the schemes. One of the two main candidates originally considered to construct public-key cryptosystems is modular exponentiation with its hard inverse operation, computing discrete logarithms. In this thesis, we study the security of protocols that make use of modular exponentiation where the exponent is a secret of the protocol. To assess the security of such protocols, one can either estimate the hardness of directly solving the discrete logarithm problem (DLP) in the groups considered by the protocols or look at implementation vulnerabilities from fast exponentiation algorithms. One way of estimating the security of protocols based on the hardness of the discrete logarithm problem is to directly study the complexity of the algorithms that solve the latter. In this thesis, we first study the asymptotic complexity of algorithms that solve DLP over finite fields “\F_{p^n}” precisely of the form where pairings take their values. These algorithms come from the index-calculus family from which the Number Field Sieve (NFS) is an example. This study allows us to draw conclusions on the security of pairing-based protocols. We also propose a first implementation of the variant Tower Number Field Sieve (TNFS) of NFS, which has better asymptotic complexity, along with a record computation of a discrete logarithm in a 521-bit finite field with TNFS. This variant had never been implemented before due to the difficulty of sieving in higher dimensions, i.e., dimensions greater than two. Finally, the security of deployed protocols not only relies on the hardness of the underlying mathematical problem but also on the implementation of the algorithms involved. Many fast modular exponentiation algorithms have piled up over the years and some implementations have brought vulnerabilities that are exploitable by side-channel attacks, in particular cache attacks. The second aspect of this thesis thus considers key recover methods when partial information is recovered from a side channel
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ADRIANO, ANDREA. "Visual Illusions and Fourier analysis as psychophysical tools to support the existence of the Number Sense." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2022. http://hdl.handle.net/10281/379213.
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L'ambiente naturale in cui gli animali sono costretti a sopravvivere modella il loro cervello e il modo in cui si comportano per adattarsi e superare le pressioni naturali. Queste pressioni selettive potrebbero aver determinato l'emergere di un antico sistema neurale adatto a estrarre rapidamente informazioni astratte da set di oggetti, come la loro numerosità, per prendere decisioni informate fondamentali per la sopravvivenza e l'adattamento. La teoria del "Senso numerico" rappresenta il modello neurale più influente che tiene conto delle prove neuropsicologiche e psicofisiche negli esseri umani e negli animali.
Tuttavia, questo modello è ancora ampiamente dibattuto a causa delle difficoltà metodologiche nell'isolare i segnali neurali relativi all'elaborazione della numerosità astratta "discreta" (cioè il numero reale di oggetti in un set) da quelli relativi ad altre caratteristiche correlate o confuse con la numerosità nell’input sensoriale grezzo (p. es., area, densità, frequenza spaziale, ecc.). La presente tesi si proponeva di indagare quali meccanismi potrebbero essere alla base delle rappresentazioni della numerosità visiva, superando le difficoltà nell'isolare le caratteristiche discrete da quelle continue. Dopo aver esaminato i principali modelli teorici e i risultati della letteratura (Capitolo 1 e 2), nel Capitolo 3 abbiamo presentato un paradigma psicofisico in cui le linee dei contorni illusori (IC) simili alla famosa illusione di Kanizsa, sono state utilizzate per manipolare la connessione (ad es., grouping) degli elementi nel set, controllando tutte le caratteristiche continue attraverso i livelli di connessione. Abbiamo mostrato che la numerosità era sottostimata quando le connessioni aumentavano, suggerendo che la numerosità si basa su oggetti percettivi segmentati piuttosto che su caratteristiche grezze di basso livello. Nel Capitolo 4, abbiamo controllato la luminosità illusoria che accompagna gli ICs.
Sfruttando le proprietà percettive dell'illusione di Kanizsa generata con induttori con contrasto inverso, abbiamo scoperto che la sottostima era insensibile alla direzione del contrasto dell'induttore, suggerendo che l'effetto era specificamente indotto da un raggruppamento di bordi indipendente dalla polarità del contrasto e non dovuto alla luminosità percepita. Nel Capitolo 5, abbiamo manipolato contemporaneamente il raggruppamento con le linee IC e la dimensione percepita dei set numerici usando illusioni di dimensioni classiche (Ponzo Illusion). Utilizzando una combinazione di illusioni visive, abbiamo dimostrato che la percezione della numerosità non si basa su segnali continui percepiti, nonostante il segnale continuo possa influenzare la percezione numerica. Nel capitolo 6 abbiamo affrontato la questione con un approccio fisico diretto: utilizzando l'analisi di Fourier per equalizzare la frequenza spaziale (SF) negli stimoli, abbiamo mostrato che l'energia dello stimolo non è coinvolta nella rappresentazione della numerosità. Piuttosto la segmentazione degli elementi e l'organizzazione percettiva hanno spiegato i nostri risultati principali. Nel capitolo 7 abbiamo anche mostrato che l'effetto del rapporto, un importante segno distintivo della codifica Weber-like della percezione numerica, non è principalmente spiegato dall'energia dello stimolo o SF. Infine, nel Capitolo 8, abbiamo anche fornito la prima evidenza empirica che la numerosità non simbolica è rappresentata spazialmente indipendentemente dal contenuto fisico (SF) degli stimoli. Nel complesso, questa tesi supporta l'idea che l'elaborazione della numerosità non si basa semplicemente su caratteristiche di basso livello, ma suggerisce piuttosto direttamente che le informazioni discrete sono al centro del senso del numero.<br>The natural environment in which animals are forced to survive shapes their brain and the way in which they behave to adapt and overcome natural pressures. These selective pressures may have determined the emergence of an evolutionary ancient neural system suited to rapidly extract abstract information from collections, such as their numerosity, to take informed decisions pivotal for survivance and adaptation. The “Number Sense” theory represents the most influential neural model accounting for neuropsychological and psychophysical evidence in humans and animals. However, this model is still largely debated because of the methodological difficulties in isolating neural signals related to “discrete” (i.e., the real number of objects in a collection) abstract numerosity processing from those related to other features correlated or confounded with numerosity in the raw sensory input (e.g., visual area, density, spatial frequency, etc). The present thesis aimed to investigate which mechanisms might be at the basis of visual numerosity representations, overcoming the difficulties in isolating discrete from continuous features. After reviewing the main theoretical models and findings from the literature (Chapter 1 and 2), in the Chapter 3 we presented a psychophysical paradigm in which Kanizsa-like illusory contours (ICs) lines were used to manipulate the connectedness (e.g., grouping strength) of the items in the set, controlling all the continuous features across connectedness levels. We showed that numerosity was underestimated when connections increased, suggesting that numerosity relies on segmented perceptual objects rather than on raw low-level features. In Chapter 4, we controlled for illusory brightness confounds accompanying ICs. Exploiting perceptual properties of the reverse-contrast Kanizsa illusion, we found that underestimation was insensitive to inducer contrast direction, suggesting that the effect was specifically induced by a sign invariant boundary grouping and not due to perceived brightness confounds. In Chapter 5, we concurrently manipulated grouping with ICs lines and the perceived size of the collections using classic size illusions (Ponzo Illusion). By using a combination of visual illusions, we showed that numerosity perception is not based on perceived continuous cues, despite continuous cue might affect numerical perception. In Chapter 6 we tackled the issue with a direct physical approach: using Fourier analysis to equalize spatial frequency (SF) in the stimuli, we showed that stimulus energy is not involved in numerosity representation. Rather segmentation of the items and perceptual organization explained our main findings. In Chapter 7 we also showed that the ratio effect, an important hallmark of Weber-like encoding of numerical perception, is not primarily explained by stimulus energy or SF. Finally, in Chapter 8, we also provided the first empirical evidence that non-symbolic numerosity are represented spatially regardless of the physical SF content of the stimuli. Overall, this thesis strongly supports the view that numerosity processing is not merely based on low-level features, and rather strongly suggests that discrete information is at the core of the Number Sense.
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Kurz, Terri L., H. Bahadir Yanik, and Jorge Garcia. "Helping a Young Child Connect Fact Family Addition and Subtraction using Tools." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-80491.
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In order to help children become effective at addition and subtraction, it is important to provide them with an opportunity to investigate and discover the interconnectedness of the two operations. Fact families are one method teachers use to try and help children develop and understand how the operations relate to one another. This paper documents a strategy that was used with a seven year old boy to help him connect addition to subtraction. The strategy incorporated flash card tools to help him create logical problems to discover the mathematical relationship of fact families. With just a few trials, the child was able to create and explain problems that demonstrated the interconnectedness of fact families through addition and subtraction. The model was successful in helping the child advance his understanding. Additionally, it can be extended to more complex addition and subtraction problems as well as multiplication and division
fact families.
Bücher zum Thema "Number of logging tools"
1
Corporation, Encyclopaedia Britannica Educational. Number tools. Encyclopaedia Britannica Educational Corp., 1997.
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2
Singha, Kamini. Borehole-radar methods: Tools for characterization of fractured rock. U.S. Dept. of the Interior, U.S. Geological Survey, 2000.
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3
Singha, Kamini. Borehole-radar methods: Tools for characterization of fractured rock. U.S. Dept. of the Interior, U.S. Geological Survey, 2000.
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Singha, Kamini. Borehole-radar methods: Tools for characterization of fractured rock. U.S. Dept. of the Interior, U.S. Geological Survey, 2000.
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Singha, Kamini. Borehole-radar methods: Tools for characterization of fractured rock. U.S. Dept. of the Interior, U.S. Geological Survey, 2000.
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Singha, Kamini. Borehole-radar methods: Tools for characterization of fractured rock. U.S. Dept. of the Interior, U.S. Geological Survey, 2000.
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Singha, Kamini. Borehole-radar methods: Tools for characterization of fractured rock. U.S. Dept. of the Interior, U.S. Geological Survey, 2000.
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Singha, Kamini. Borehole-radar methods: Tools for characterization of fractured rock. U.S. Dept. of the Interior, U.S. Geological Survey, 2000.
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Fokin, Sergey, and Oksana Shport'ko. Logging production: technologies and equipment. INFRA-M Academic Publishing LLC., 2021. http://dx.doi.org/10.12737/1058986.
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The textbook discusses the main stages of logging operations and forest transport, as well as technologies and types of equipment for performing work on lower timber yards, including technologies for stacking, loading and dumping of harvested timber. A separate chapter of the book is devoted to the issues of ensuring safety during these works. A detailed description of the construction of logging machines, motor tools, vehicles, machines, aggregates and lines for primary processing of wood (stumping of branches, bucking and cutting of whips, debarking of sorts), lifting and transport machines and devices is given.
 Meets the requirements of the federal state educational standards of higher education of the latest generation.
 It is intended for students in the field of training 35.03.01 "Forestry" and in the specialty 35.02.02 "Logging technology".
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Kehutanan, Indonesia Direktorat Jenderal Bina Produksi. Director General of Production Forest Development Guidance number: P.02/VI/-BPPHH/2010 on guidance of performance evaluation of sustainable production forest management and timber legality verification. Ministry of Forestry, 2010.
Den vollen Inhalt der Quelle findenBuchteile zum Thema "Number of logging tools"
1
Gooneratne, Chinthaka P., Bodong Li, Max Deffenbaugh, and Timothy Moellendick. "Logging Tools in Hydrocarbon Wells." In Instruments, Measurement Principles and Communication Technologies for Downhole Drilling Environments. Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-030-04900-3_4.
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2
Boyeldieu, C., and J. Draxler. "Deep Well Formation Logging — The Problems. The Logging Tools." In Exploration of the Deep Continental Crust. Springer Berlin Heidelberg, 1987. http://dx.doi.org/10.1007/978-3-642-45616-9_22.
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Butler, J., A. F. Avery, B. Darling, P. B. Kemshell, and A. D. Knipe. "Modelling of Oilwell Borehole Logging Tools." In Optimization of the Production and Utilization of Hydrocarbons. Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-011-2256-6_8.
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Crandall, Richard, and Carl Pomerance. "Number-Theoretical Tools." In Prime Numbers. Springer New York, 2001. http://dx.doi.org/10.1007/978-1-4684-9316-0_2.
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Unterberger, André. "The basic tools." In Pseudodifferential Methods in Number Theory. Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-92707-7_2.
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Nakazawa, Naoya, and Hiroshi Nakazawa. "Basic Concepts and Tools." In Random Number Generators on Computers. Jenny Stanford Publishing, 2024. http://dx.doi.org/10.1201/9781003410607-1.
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Chen, Lei, and Lu Zhang. "Optimal Scheduling User Number in Massive MIMO with QoS Requirement." In Simulation Tools and Techniques. Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-32216-8_61.
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Pandey, Chetan, Amit Juyal, and Ankur Dumka. "Vehicle Number Extraction Using Open Source Tools." In Advances in Information Communication Technology and Computing. Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-5421-6_40.
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Xu, Da-hua, and Yong-sheng Chao. "Design the Network Bus of Logging Downhole Tools on 10BASE-T1S Network." In Springer Series in Geomechanics and Geoengineering. Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-97-0479-8_32.
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Tremblay, Yann, and Sophie Bertrand. "“Bio-logging” as a Tool to Study and Monitor Marine Ecosystems, or How to Spy on Sea Creatures." In Tools for Oceanography and Ecosystemic Modeling. John Wiley & Sons, Inc., 2016. http://dx.doi.org/10.1002/9781119330226.ch5.
Der volle Inhalt der QuelleKonferenzberichte zum Thema "Number of logging tools"
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Yang, Fenfen, and Yi Gao. "Research on Weak Signal Processing Methods for Electrical Imaging Logging Tools." In 2024 3rd International Symposium on Semiconductor and Electronic Technology (ISSET). IEEE, 2024. https://doi.org/10.1109/isset62871.2024.10779809.
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2
Price, Jimmy, Darren Gascooke, Anthony Van Zuilekom, and Christopher Jones. "IMPROVING RESERVOIR TESTING AND SAMPLING IN H2S CONTAMINATED FLUIDS BY ADAPTING STATE-OF-THE-ART SEMICONDUCTOR THIN FILM TECHNOLOGY FOR DOWNHOLE TESTER TOOLS." In 2021 SPWLA 62nd Annual Logging Symposium Online. Society of Petrophysicists and Well Log Analysts, 2021. http://dx.doi.org/10.30632/spwla-2021-0026.
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Accurate reservoir fluid identification and sampling of hydrogen sulfide (H2S) contaminated fluids is difficult to achieve due its consumption by the interior of downhole tool surfaces prior to sampling or measurement. For low PPM level concentrations, this fact does not change, despite recent tool advances utilizing NACE compliant materials. Consequently, H2S concentrations are typically under-reported which adversely affects production and presents significant health safety and environment concerns. Historically, only sampling bottles have been coated to preserve H2S concentrations during transit to laboratories with a material that is resistant to H2S reactivity to enable more representative measurements. However, only very recent efforts have transitioned the focus toward successfully coating the interior of the tools. This paper details a state-of-the-art technology, initially developed and heavily leveraged from the semiconductor industry. The technology is adapted to coat the interior surfaces of downhole tools with a chemically resistant dielectric thin film. New developments now provide the benefit of the process being safe, able to be performed at atmospheric pressure and temperature conditions, and portable; thus, allowing the coating process to be deployed to field locations. The method involves atomic layer deposition (ALD) technology to be plumbed in directly to a downhole tool and conformally deposit a thin layer (e.g. < 1 micron) of highly durable H2S-resistant sapphire to the entire interior tool surface. An automated procedure has been developed allowing the versatility to accommodate a number of unique geometries inherent of different formation tester configurations. New advances in Quartz Crystal Microbalance sensors are also realized in-situ to optimize (in real-time) the efficiency of the process and ensure uniform and conformal coverage is obtained in the fastest and safest manner. Laboratory testing on a prototype system demonstrated uniform and conformal coverage of a ~ 500 nm thick sapphire film resistant to flaking and scratching. Accelerated lifetime stress testing demonstrated high durability relative to expected tool life. Testing of coated and uncoated tools show the coating is successful at the 50ppm level H2S for up to 4 days. These results are contrasted with similar tool body samples not coated with the H2S-resistant ALD sapphire and subject to the same H2S conditions. To show the coating’s durability, subsequent experiments flowed mud-based drilling fluid through both the tool body and sample chambers, followed by thorough cleaning and successful repeating the same 50ppm H2S test. Exposure of the sapphire coated tool body and sample chambers to various concentrations of H2S demonstrated zero loss. Ultimately this technique represents a new opportunity to gather representative formation samples containing low concentrations of H2S.
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Zhu, Jun, Yong Die, Yuanshi Tian, and John Zhou. "DECIPHERING THE CAPABILITIES OF LOOK-AHEAD METHODS IN LWD." In 2021 SPWLA 62nd Annual Logging Symposium Online. Society of Petrophysicists and Well Log Analysts, 2021. http://dx.doi.org/10.30632/spwla-2021-0024.
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The use of electromagnetic logging tools while drilling to investigate the space in front of the drill-bit and to predict the geologic strata and/or fluid property ahead has been one of the industry-focuses in recent years. The commercial look-ahead tools have two main designs based on the published tool configurations and data-channel definitions. The first type employs combinations of tilted coils to acquire multiple or all components of electromagnetic fields and presents logs defined in novel expressions as functions of these field components. The second kind uses combination of the voltage measurements from orthogonal coils (coils pointing along and perpendicular to tool-axis) and the propagation resistivity logs from coaxial coils of large coil-spacing. This work starts with reviewing the tool physics and the mathematic expressions defining the logs. The look-ahead capabilities are then investigated by considering the case where a borehole is perpendicular to the formation boundaries. It is found that the necessary information for forward detection applications is exclusively from the apparent resistivity logs, not the so-called geo-signals or any other logs. We further explore an ideal scenario, i.e., to detect the presence of a good conductor in front of a high resistivity formation to obtain the asymptotic behaviors for the two measurement types. The asymptotic expressions lay the foundation to understanding the intrinsic differences between the two methods. The insights derived from the theoretical work and the subsequent modeling results for a broad set of models define the response characteristics and the probing capabilities of the look-ahead techniques. It is realized that the look-ahead instrument design can be simplified, such as using only the familiar three-coil coaxial configuration with a suitable long coil-spacing and multiple carefully chosen operating frequencies to achieve a robust detection-distance coverage. It is worth to point out that the commercially available look-ahead services are mainly applicable to vertical and inclined wells so far. For look-ahead applications in horizontal wells, due to the contribution of the geologic and fluid boundaries lateral to the tool and the inhomogeneities ahead of the drill-bit, there is no reliable method yet to simultaneously solve the large number of unknown parameters associated other than some special situations. The look-ahead evaluation in the horizontal wells must be investigated further by understanding the characteristics of exponential attenuation and geometric spreading of the electromagnetic fields in a conductive formation and the inherent relatively poor resolution through combining with other detection physics and the introduction of proper geologic model constraints.
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Sviridov, Mikhail, Anton Mosin, Sergey Lebedev, and Ron Thompson. "VENDOR-NEUTRAL STOCHASTIC INVERSION OF LWD DEEP AZIMUTHAL RESISTIVITY DATA AS A STEP TOWARD EFFICIENCY STANDARDIZATION OF GEOSTEERING SERVICES." In 2021 SPWLA 62nd Annual Logging Symposium Online. Society of Petrophysicists and Well Log Analysts, 2021. http://dx.doi.org/10.30632/spwla-2021-0103.
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While proactive geosteering, special inversion algorithms are used to process the readings of logging-while-drilling resistivity tools in real-time and provide oil field operators with formation models to make informed steering decisions. Currently, there is no industry standard for inversion deliverables and corresponding quality indicators because major tool vendors develop their own device-specific algorithms and use them internally. This paper presents the first implementation of vendor-neutral inversion approach applicable for any induction resistivity tool and enabling operators to standardize the efficiency of various geosteering services. The necessity of such universal inversion approach was inspired by the activity of LWD Deep Azimuthal Resistivity Services Standardization Workgroup initiated by SPWLA Resistivity Special Interest Group in 2016. Proposed inversion algorithm utilizes a 1D layer-cake formation model and is performed interval-by-interval. The following model parameters can be determined: horizontal and vertical resistivities of each layer, positions of layer boundaries, and formation dip. The inversion can support arbitrary deep azimuthal induction resistivity tool with coaxial, tilted, or orthogonal transmitting and receiving antennas. The inversion is purely data-driven; it works in automatic mode and provides fully unbiased results obtained from tool readings only. The algorithm is based on statistical reversible-jump Markov chain Monte Carlo method that does not require any predefined assumptions about the formation structure and enables searching of models explaining the data even if the number of layers in the model is unknown. To globalize search, the algorithm runs several Markov chains capable of exchanging their states between one another to move from the vicinity of local minimum to more perspective domain of model parameter space. While execution, the inversion keeps all models it is dealing with to estimate the resolution accuracy of formation parameters and generate several quality indicators. Eventually, these indicators are delivered together with recovered resistivity models to help operators with the evaluation of inversion results reliability. To ensure high performance of the inversion, a fast and accurate semi-analytical forward solver is employed to compute required responses of a tool with specific geometry and their derivatives with respect to any parameter of multi-layered model. Moreover, the reliance on the simultaneous evolution of multiple Markov chains makes the algorithm suitable for parallel execution that significantly decreases the computational time. Application of the proposed inversion is shown on a series of synthetic examples and field case studies such as navigating the well along the reservoir roof or near the oil-water-contact in oil sands. Inversion results for all scenarios confirm that the proposed algorithm can successfully evaluate formation model complexity, recover model parameters, and quantify their uncertainty within a reasonable computational time. Presented vendor-neutral stochastic approach to data processing leads to the standardization of the inversion output including the resistivity model and its quality indicators that helps operators to better understand capabilities of tools from different vendors and eventually make more confident geosteering decisions.
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Abdulghani, A. J., H. A. Muailu, and M. N. Shurafa. "State-Of-The-Art Technologies and Engineering Approach to Production Logging of Penta Lateral Electrical Submersible Pump Driven Offshore Wells." In ADIPEC. SPE, 2023. http://dx.doi.org/10.2118/215992-ms.
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Abstract As the number of multi-lateral complex wells and advanced completions deployment rises, the demand for advanced and reliable Coiled Tubing (CT) intervention and logging solutions is also increasing. Well complexity is associated with the number of laterals, extended-reach open-hole, complex well trajectories, and the use of advanced completions such as Electrical Submersible Pumps (ESP), Inflow Control Valves (ICV), Inflow Control Devices (ICD), and other completion accessories. This paper provides a comprehensive engineering approach for logging multi-lateral wells with slim ESP completions. Technologies play a major role in enabling CT logging in complex wells. The state-of-the-art electrical CT multi-lateral re-entry tool is a key enabler to locate and access the laterals, and specialized logs are utilized to verify the location of the intended laterals. Another enabler in multi-lateral logging is the retractable logging tool, which provides flexibility to navigate across the open-hole junctions and windows, minimizing the risk of damaging the logging tools. The level of complexity increases when these multi-lateral wells are completed with ESP, especially in an offshore environment. Special tools must be used to pass through the ESP slim completion, and the CT Bottom Hole Assembly (BHA) must be compact to comply with the offshore environment space limitation. The engineering approach, through proper per-job simulation and risk assessment evaluation, besides selecting the right BHA tools, was an essential factor in completing complex logging operations safely and successfully. Moreover, a decision-making tree with live engineering support to guide the operational team to the right action played a role in a successful operation. Additionally, the synergy between engineering and operation is another aspect of success, to make timely decisions during the operation. The presented state-of-the-art technologies and engineering approaches were proven effective in logging multi-lateral slim ESP completions successfully verified on a Penta lateral ESP-driven well.
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Gonzalez, Andres, Zoya Heidari, and Olivier Lopez. "A NEW OPTIMIZATION METHOD FOR ENHANCED FORMATION EVALUATION AND ROBUST PHYSICS-BASED AUTOMATIC ROCK CLASSIFICATION USING HIGH-RESOLUTION CT-SCAN IMAGE DATA AND CONVENTIONAL WELL LOGS." In 2021 SPWLA 62nd Annual Logging Symposium Online. Society of Petrophysicists and Well Log Analysts, 2021. http://dx.doi.org/10.30632/spwla-2021-0030.
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Conventional formation evaluation provides fast and accurate estimations of petrophysical properties in conventional formations through conventional well logs and routine core analysis (RCA) data. However, as the complexity of the evaluated formations increases conventional formation evaluation fails to provide accurate estimates of petrophysical properties. This inaccuracy is mainly caused by rapid variation in rock fabric (i.e., spatial distribution of rock components) not properly captured by conventional well logging tools and interpretation methods. Acquisition of high-resolution whole-core computed tomography (CT) scanning images can help to identify rock-fabric-related parameters that can enhance formation evaluation. In a recent publication, we introduced a permeability-based cost function for rock classification, optimization of the number of rock classes, and estimation of permeability. Incorporation of additional petrophysical properties into the proposed cost function can improved the reliability of the detected rock classes and ultimately improve the estimation of class-based petrophysical properties. The objectives of this paper are (a) to introduce a robust optimization method for rock classification and estimation of petrophysical properties, (b), to automatically employ whole-core two-dimensional (2D) CT-scan images and slabbed whole-core photos for enhanced estimates of petrophysical properties, (c) to integrate whole-core CT-scan images and slabbed whole-core photos with well logs and RCA data for automatic rock classification, (d) to derive class-based rock physics models for improved estimates of petrophysical properties. First, we conducted formation evaluation using well logs and RCA data for estimation of petrophysical properties. Then, we derived quantitative features from 2D CT-scan images and slabbed whole-core photos. We employed image-based features, RCA data and CT-scan-based bulk density for optimization of the number rock classes. Optimization of rock classes was accomplished using a physics-based cost function (i.e., a function of petrophysical properties of the rock) that compares class-based estimates of petrophysical properties (e.g., permeability and porosity) with core-measured properties for increasing number of image-based rock classes. The cost function is computed until convergence is achieved. Finally, we used class-based rock physics models for improved estimates of porosity and permeability. We demonstrated the reliability of the proposed method using whole-core CT-scan images and core photos from two siliciclastic depth intervals with measurable variation in rock fabric. We used well logs, RCA data, and CT-scan-based bulk-density. The advantages of using whole-core CT-scan data are two-fold. First, it provides high-resolution quantitative features that capture rapid spatial variation in rock fabric allowing accurate rock classification. Second, the use of CT-scan-based bulk density improved the accuracy of class-based porosity-bulk density models. The optimum number of rock classes was consistent for all the evaluated cost functions. Class-based rock physics models improved the estimates of porosity and permeability values. A unique contribution of the introduced workflow when compared to previously documented image-based rock classification workflows is that it simultaneously improves estimates of both porosity and permeability, and it can capture rock class that might not be identifiable using conventional rock classification techniques.
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Hekimoglu, Kemal C., Filippo Casali, and Antonio Bonetti. "ADDRESSING RESERVOIR HETEROGENEITY BY INTEGRATION OF GEOCHEMISTRY AND PETROPHYSICAL LOGS IN CARBONATE PROSPECTS." In 2021 SPWLA 62nd Annual Logging Symposium Online. Society of Petrophysicists and Well Log Analysts, 2021. http://dx.doi.org/10.30632/spwla-2021-0004.
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Formation evaluation challenges in highly fractured, stacked reservoirs with multiple source rocks and structural complexities that have complicated charging histories are common in the Middle East. Finding additional pay zones, understanding the contribution of individual oils to the overall production, or evaluating the compartmentalization within the reservoir by resolving the heterogeneity of the reservoir rocks are to name but a few. This work tries to understand the challenges posed by the subsurface complexities and attempts to find answers through physical evidence, using both onsite data acquired during drilling and data gathered through organic and inorganic laboratory measurements. Formation evaluation challenges are mostly attributed to formation heterogeneity, which we have aimed to address through the integration of petrophysical and geochemical data within this work. This project encompasses the integration of petrophysical and geochemical analyses of the reservoir rocks. Geochemical data have provided the ability to make maturity, richness, and other character interpretations and will be combined with important petrophysical properties of the carbonate intervals to predict reservoir heterogeneities. These interpretations could support perforation interval selection on subsequent wells in the field through the understanding of the mobility of the oils and, ultimately, production allocation. Best practices for thermally extracting hydrocarbons from drill cuttings, quality-controlling advanced mud gas data, and interpretive processes together with the entire workflow followed will also be elaborated. The analysis has the objectives of establishing results to support completion decisions through understanding reservoir quality, reservoir fluid communication, and compartmentalization specific to the basin studied. The petrophysical reservoir properties such as hydrocarbons in place, mobility of the oils, porosity, permeability, fracture intensity, geomechanical properties (brittle vs. ductile), and production allocation will be tied in to geochemical analyses to this extent. The focal point of the work is ascertaining and characterizing both the reservoir properties using a number of integrated analytical techniques on DST oil samples of 12 offset wells and rock cuttings, as well as petrophysical logs and advanced mud gas data. The concepts, tools, and methods that have been demonstrated for evaluating crude oils, natural gases, and petrophysical characteristics of the rocks are applicable to many problems in petroleum production and field development as well as exploration efforts.
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Liu, Shanshan, and Zhiming Wang. "Formation Grain Size Profile Prediction Model Considering the Longitudinal Continuity of Reservoir Using Artificial Intelligence Tools." In SPE/IATMI Asia Pacific Oil & Gas Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/205683-ms.
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Abstract Grain size characteristics (d50, UC) of formation sands are crucial parameters in a sand control design. UC and d50 are commonly derived from sieve or laser particle size analysis (LPSA) techniques on a limited number of core samples in the process of drilling, which cannot represent the variations of grain sizes in the formation by the limited number of core samples. Moreover, staged and hierarchic design of sand control usually needs the whole longitudinal distribution profile of grain size. The grain size characteristics of the reservoir are formed in the process of a long history and have a good correlation with the formation environment of the sediments. Sand control design can only use test well data, because of lacking actual producing position cores. The vertical and horizontal anisotropy and heterogeneity of reservoirs bring difficulties and greater risks to the design of sand control schemes. Therefore, it is very important to find a simple and effective reservoir granularity prediction method. The existing prediction models by artificial intelligence method use single point logging data as eigenvalues to predict d50 and UC without considering the longitudinal continuity of data. This paper presents an efficient solution to predict grain size profile based on conventional logging curves by using four machine learning method (ANN, Random forest, XGBoost, SVM). In order to make full use of the geological continuity of the reservoir, the longitudinal continuous points according to the spatial correlation are adopted as the machine learning feature parameters from the perspective of geological analysis and the data-driven grain size profile prediction model are established by using the logging curve trend and background information, which further improves the prediction accuracy of the model and provides basic data for sand control. The ANN model of five point mapping has the best prediction effect in predicting d50 with a highest correlation coefficient 0.819 and a lowest error MAE 9.59. The XGBoost model of five point mapping has the best prediction effect in predicting UC with a highest correlation coefficient 0.402 and a lowest error RMSE 1.15. This method has been successfully used in offshore oil field in sand control optimization.
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Cai, Shanqing, Juntao Liu, Xusheng Wang, and Zhiyi Liu. "THEORETICAL METHOD AND EXPERIMENTAL RESEARCH ON HIGH PRECISION FOUR DETECTOR DENSITY LOGGING." In 2021 SPWLA 62nd Annual Logging Symposium Online. Society of Petrophysicists and Well Log Analysts, 2021. http://dx.doi.org/10.30632/spwla-2021-0066.
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In order to better evaluate the formation density, casing and cement ring integrity under casing well conditions, a high precision four detector density logging tool was designed and developed. Theoretical methods and experimental studies are carried out on the relationship between the measured data of the four detector density logging tool and the formation density, casing thickness and cement ring thickness. By carrying out a large number of Monte Carlo simulations and setting up different experimental measurement devices, the effects of casing thickness, cement ring thickness and formation density on the gamma values of the four detectors are studied. The main factors affecting the count rate are determined and the counting response relations of detectors with different source distances are obtained. Based on the theoretical analysis of gamma transport and experimental measurement data, the measured gamma spectrum of each detector is divided into four energy windows, and the nonlinear response model of gamma counting of different energy windows with formation density, casing thickness, cement ring density and cement ring thickness is established. The forward model is used to invert the parameters such as the thickness of cement ring and casing, and the results are compared with the actual experimental values. The results show that with the change of downhole environment, the calculation of cased hole parameters by this physical model has been greatly challenged. In order to overcome the shortcomings of multiple fitting parameters of the forward model and large calculation errors under complex logging environment, a neural network prediction model predicting casing well parameters is established using 60-100keV, 100-140keV, 140-200keV, 200-540keV four energy window count rate. Thegamma-ray counts measured by the four detectors andthe source distance of each detector are regarded asmodel input variables. Experimental results andsimulation results show that the absolute error of theformation density calculation by artificial intelligence method is less than 0.33g/cm3, the absolute error of the casing thickness calculation is less than 0.15cm, and the absolute error of the cement ring thickness calculation is less than 1.2cm. The results show that the four detector density logging tool can be used as an important technical means to evaluate the formation density and the integrity of the casing and cement ring under the condition of cased hole.
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Mussayev, G., B. Saduakassov, A. Nurmukhanbetov, et al. "Wireline Surveillance Operations with Minimum Impact to Production." In SPE Caspian Technical Conference and Exhibition. SPE, 2023. http://dx.doi.org/10.2118/217634-ms.
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Abstract This paper is aimed to share recent best practices in wireline well interventions in Tengiz field, specifically aimed to reduce the intervention impact to LPO (Loss Production Opportunity). Three main practices will be shared: Installation of protecting cages to conduct wireline interventions on MWPs. TCO has Multi-WellPad (MWP) facilities with a number of wells that hooked up into one production system. TCO must collect subsurface data for RoK requirements and Reservoir Management. In the past, TCO had to shut-in entire MWP to execute surveillance operations, which would negatively impact production. An intermediate improvement was to shut-in adjacent neighbor wells if any intervention scope on the working well is required, with the aim for the team to review the procedure to identify possible methods and safeguards to allow continued production to those adjacent wells to mitigate production impact. Previously, TCO could flow the well at a minimum rate in a smaller ID completion to control lifting forces, but by utilizing a different cable and logging unit provided a safer execution of PLT logging in high-rate wells that reduced uncertainties of zonal allocation and provided more accurate data. Utilization of combined PLT, RST and HFND logging tools string to maximize gathering of quality information with minimum well downtime. Using heavy cable to conduct high-rate production logging in small diameter liners. To minimize well downtime during wireline surveillance, we offer PLT\RST\Noise tool into one toolstring within taller lubricator. Combination of 3 tools provide large picture in wider range with minimum well downtime. This paper aims to provide an overview on the surveillance operations processes improvements and to share the best practices in planning of operational activities at the field with minimized impact on overall field production.
Berichte der Organisationen zum Thema "Number of logging tools"
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Wright, Andrew. Long-Term High-Temperature High-Pressure Cable for Geothermal Logging Tools. Office of Scientific and Technical Information (OSTI), 2024. https://doi.org/10.2172/2516861.
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Tao, Gang, and Brian Wagg. PR-244-16704-R01 Casing Corrosion Logging Tool Test. Pipeline Research Council International, Inc. (PRCI), 2019. http://dx.doi.org/10.55274/r0011626.
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Pipeline Research Council International, Inc. (PRCI) contracted C-FER Technologies (1999) Inc. ("C-FER") to conduct a laboratory testing program to evaluate the performance of various casing corrosion logging techniques and tools. An additional objective of this test program was to evaluate the influence of the wellhead and outer casing strings on the response of magnetic flux leakage tools, and to evaluate the thru-tubing logging technique. A test well was set up with a string of 4.5 inch diameter tubing joints (~150 ft total length) hanging concentrically inside a string of 7 inch diameter casing joints (~75 ft total length) attached to a wellhead. The entire test well assembly was hung vertically within C-FER's Deep Well Simulator. A combination of artificial metal loss features and natural corrosion features were present on the tubing and casing joints. Several casing corrosion logging vendors were invited to log the test tubing string with various logging tools. The logging test results were provided to C-FER and analysis was performed to evaluate the performance of each logging tool and the associated interpretation techniques. This report describes the test setup and procedure, the tool performance evaluation results, and considerations for future initiatives.
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D'Amico, Angela, Christopher Kyburg, and Rowena Carlson. Software Tools for Visual and Acoustic Real-Time Tracking of Marine Mammals: Whale Identification and Logging Display (WILD). Defense Technical Information Center, 2010. http://dx.doi.org/10.21236/ada533470.
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Olson, L. C., R. D. Knight, H L Crow, and H. A. J. Russell. Chemostratigraphic logging of the Lower Ordovician and Precambrian, Bells Corners borehole calibration facility, Ottawa, Ontario. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/330519.
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Geochemical data were collected from a 120-meter-deep borehole (BC81-2) located at the Geological Survey of Canada's Bells Corners Borehole Calibration Facility in Ottawa, Ontario. This report documents geochemical data collected for the most frequently logged of the six boreholes located at the facility. The geochemical data were collected using a portable X-ray fluorescence (pXRF) spectrometer with a subset of samples collected for modern laboratory based fusion and multi-acid methods to calibrate the pXRF data for improved accuracy. Borehole geochemistry provides a characterization of Precambrian and overlying Ordovician rocks in the Ottawa area that augments the understanding of geophysical properties obtained from the calibration borehole. The combined geochemical and geophysical datasets further define rock characteristics, formational boundaries, as well as alteration zones. The results demonstrate the usefulness of pXRF derived geochemical data and chemostratigraphy of rock cores. The chemostratigraphic data augment data collected with spectral gamma logging tools and support an enhanced interpretation of geological contacts across transitional boundaries and the nature of the matrix mineralogy.
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Brackney, L. Mobile Building Energy Audit and Modeling Tools: Cooperative Research and Development Final Report, CRADA Number CRD-11-00441. Office of Scientific and Technical Information (OSTI), 2013. http://dx.doi.org/10.2172/1076665.
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Haring, Christopher, and David Biedenharn. Channel assessment tools for rapid watershed assessment. Engineer Research and Development Center (U.S.), 2021. http://dx.doi.org/10.21079/11681/40379.
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Existing Delta Headwaters Project (DHP) watershed stabilization studies are focused on restoration and stabilization of degraded stream systems. The original watershed studies formerly under the Demonstration Erosion Control (DEC) Project started in the mid 1980s. The watershed stabilization activities are continuing, and because of the vast number of degraded watersheds and limited amount of yearly funding, there is a need for developing a rapid watershed assessment approach to determine which watersheds to prioritize for further work. The goal of this project is to test the FluvialGeomorph (FG) toolkit to determine if the Rapid Geomorphic Assessment approach can identify channel stability trends in Campbell Creek and its main tributary. The FG toolkit (Haring et al. 2019; Haring et al. 2020) is a new rapid watershed assessment approach using high-resolution terrain data (Light Detection and Ranging [LiDAR]) to support U.S. Army Corps of Engineers (USACE) watershed planning. One of the principal goals of the USACE SMART (Specific Measureable Attainable Risk-Informed Timely) Planning is to leverage existing data and resources to complete studies. The FG approach uses existing LiDAR to rapidly assess either reach-specific analysis for smaller more focused studies or larger watersheds or ecosystems. The rapid assessment capability can reduce the time and cost of planning by using existing information to complete a preliminary watershed assessment and provide rapid results regarding where to focus more detailed study efforts.
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Dashtey, Ahmed, Patrick Mormile, Sandra Pedre, Stephany Valdaliso, and Walter Tang. Prediction of PFOA and PFOS Toxicity through Log P and Number of Carbon with CompTox and Machine Learning Tools. Florida International University, 2024. http://dx.doi.org/10.25148/ceefac.2024.00202400.
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Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are two major groups of PFAS will be subjected to the Maximal Contamination Concentration (MCL) of 4 ng/l in drinking water to be implemented by the U.S. EPA by 2025. How to accurately predict toxicity of PFAS with varied carbon chain length is important for treatment and sequential removal from drinking water. This study presents Quantitative Structure and Activity Relationship (QSAR) models developed through both linear regression and two order regression. Log P is compiled from reference and carbon content is counted as the molecule represented. Bioconcentration potential is predicted from CompTox.The results suggest that as log P and carbon content increase, the bioconcentration potential of PFCAs also increases. In other words, larger PFCA molecules tend to be easier to bioaccumulate in living organisms. This finding is crucial because bioconcentration refers to the accumulation of substances from water directly into living organisms through the process of passive diffusion across cell membranes. On the other hand, 96-hour fathead minnow LC50 has an inverse relationship, with higher LC50 values associated with lower log P and fewer carbons. The varying R-squared values across methods indicate differing degrees of correlation, underscoring the impact of compound structure on aquatic toxicity. Similarly, for oral rat LD50 and 48-hour D. magna LC50, the R-squared values reflect moderate to strong correlations with log P and the number of carbons. As the log P and carbon content decrease,the toxicity expressed in LC50 or LD50 increases. This relationship underscores the role of chemical properties in influencing the toxicity of PFCAs across different organisms and exposure routes. For instance, the negative correlation between log P and aquatic toxicity (96-hour fathead minnow LC50 and 48-hour D. magna LC50) suggests that compounds with higher hydrophobicity (higher log P) and more carbons may exhibit lower acute toxicity to aquatic organisms.
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McCormack, Caitilin, Steve Jennings, and Linda Kenni. Gender and LGBTQI+ Policy and Programming in Vanuatu: Opportunities, challenges, capacity, and tools for change. Oxfam, 2020. http://dx.doi.org/10.21201/2020.6508.
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In 2016 the government of Vanuatu introduced a National Gender Equality Policy. A second phase of the policy will be implemented in 2020–2024. Insights from key informants working on gender in Vanuatu reveal that there have been some positive developments in the first policy phase. A number of challenges remain, however, including limited capacity in a number of key institutions, and resistance to progress caused by prevailing conservative and patriarchal values and beliefs in Vanuatu. In the absence of other legal instruments for LGBTQI+/SOGI equality, perspectives vary on whether this aspect of gender equality should be included in the revised policy.
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Grout, Ray. Tools for Design and Scale-Up of Solar Thermochemical Reactors: Cooperative Research and Development Final Report, CRADA Number CRD-13-00530. Office of Scientific and Technical Information (OSTI), 2022. http://dx.doi.org/10.2172/1875071.
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Tomaskova, Hana, Matej Kucera, Marek Stodola, and Anna Kagstrom. Systematic review of tools available to measure mental health literacy in children and adolescents. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, 2022. http://dx.doi.org/10.37766/inplasy2022.9.0054.
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Review question / Objective: The aim of the present study was to conduct a systematic search in order to find available tools for monitoring and evaluating the mental health literacy of children and adolescents under the age of 19 years. Condition being studied: Mental health literacy is an essential part of mental illness prevention and early-identification. Number of tools exist to assess mental health literacy in the adult population. However, very few studies focus on tools that are aimed at assessing mental health literacy of children and adolescents, and evaluate quality of these tools.