bluuebunny/crossref_metadata_2025_split huggingface dataset:
Avaliação de hipsômetros e operadores na mensuração de árvores de Eucalyptus urograndis de tamanhos diferentes
Authors: Mayrinck Rafaella Carvalho , Oliveira Ximena Mendes de , Silva Gabriela Cristina Costa , Vitor Paula Carolina Gomides , Ferraz Filho Antonio Carlos 
Published: March 2017

<p>A mensuração da altura de forma acurada é extremamente importante na ciência florestal, pois, influencia diretamente na predição do volume individual das árvores, bem como na volumetria de um povoamento e em todo o sistema de prognose. Por ser feita de forma indireta, é sujeita a erros, que devem ser minimizados. Assim, deve se usar o hipsômetro que proporcione menor erro, além de um operador treinado para o procedimento. Nesse estudo objetivou-se testar a acurácia do hipsômetro e operador em relação a árvores de <em>Eucalyptus urograndis</em> de tamanhos diferentes. Os dados foram coletados em um plantio de <em>Eucalyptus urograndis</em> em Turmalina, MG. Três árvores foram selecionadas, classificadas em pequena (12,1 m), média (18,9 m) e grande (25,2 m). Seis operadores mediram cada uma das árvores usando 4 hipsômetros (Prancheta dendrométrica, Clinômetro digital, Suunto e Vertex) 5 vezes. Posteriormente, realizou-se o abate das árvores e a obtenção da altura real com uma trena. Para analisar os dados, foi feita uma análise de variância, teste de Tukey e teste T. Os resultados mostram que houveram diferenças entre os valores encontrados pelos observadores, o que salienta a necessidade de treinamento. Todos os instrumentos geraram valores confiáveis. Para árvores mais baixas, o Vertex foi o instrumento mais confiável e para árvores maiores o Clinômetro digital foi o instrumento mais indicado. </p><p align="center"><strong><em>Evaluation of hypsometers and operators in measuring tree heights in </em></strong><em>Eucalyptus urograndis<strong> with different sizes</strong></em></p><p><strong>Abstract</strong><strong>: </strong>The accurate mensuration of tree hight is very important in forest science because it influences directly the individual tree volume, stand volume prediction and all the prognosis system. Due to the fact it is made indirectly, errors can occur, and they should be minimized. Hence, one should use hypsometers, which lead to a minor error and a trained operator to do it. This study aims to test the accuracy of hypsometers and operator, regarding the size of the tree, classified as small (12,1 m), medium (18,9 m) and large (25,2 m). Data was of 3 trees from a <em>Eucalypus urograndis</em> plantation in Turmalina, MG. Six operators measured the trees using 4 hypsometers (Dendrometric clipboard, Digital clinometer, Suunto and Vertex) 5 times each. The trees were felled and the real height of the trees were taken using a measure tape. Data was analysed by Analysis of variance, Tukey test and T test. The results showed difference between values found by different operators and highlight the need for training. All hypsometers were accurate. Measuring smaller trees, Vertex was the best one and measuring the higher ones, Digital clinometer was the best.</p>
A porosidade no Largo da Batata, em São Paulo [SP]: cultura como patrimônio imaterial na cidade contemporânea
Authors: Blümer Mariana Piovan , Victal Jane 
Published: March 2017

O Largo da Batata torna-se objeto de estudo na busca pela compreensão da Porosidade na cidade como condicionante de ocupação e uso dos espaços públicos pelo ser humano, assim como este próprio se construindo a partir de experiências possíveis por imersão nessa esfera. O espaço público identificado como um espaço de significações, constituído por camadas que denotam as transformações do sentido de lugar. Nesse contexto, os poros são indiretamente percebidos, pois não são possíveis de serem interpretados apenas pelas formas físicas (visuais). Trata-se de uma análise fenomenológica das formas de ocupação atuais somadas às dinâmicas de uso e identidade desse lugar ao longo do tempo, as quais são entendidas aqui como membranas. Investiga-se, portanto, quais são os parâmetros que definem a porosidade? Há relação entre as condicionantes de porosidade física e de porosidade social? Como elas qualificam os espaços urbanos públicos no cotidiano citadino (espaço existencial)? É possível construir porosidade?
Case Study of Section Milling Run in Abrasive Salt Dome Formation and Technological Development for Multi-String Section Milling
Authors: Smalley Michael T. , Hay Christopher , Teale David W. , Haq Mohammed A. 
Published: March 2017

Abstract
The Stratton Ridge salt dome located in Brazoria County, Texas, has been used extensively by industry for brining operations and for the storage of liquid hydrocarbons, refined products, and natural gas. The shape of the dome has been defined by several hundred oil and gas wells drilled over the top of this highly anomalous geologic diapir structure. Cavern operations at Stratton Ridge historically are known to have experienced a number of problems. These difficulties and "off-normal events" include severe lost circulation while drilling through cap-rock, sheared well casings, corrosion, shifting, and encountering hydrocarbon products that appear to have escaped from the storage cavern.
This paper describes a case study of section milling in the gas storage cavern of this highly abrasive salt dome, the challenges faced, and how the challenges were detected and overcome. The unique aspect of this case study is the introduction of new section milling technology. New technologies in multiple-string section milling plays an important role to improve operational performance, reduce costs, and eliminate NPT—especially in the current global environment of low oil prices. This paper also touches the R&D development for multi-string section milling in various settings.
Improved Bottomhole Pressure Control with Wired Drillpipe and Physics-Based Models
Authors: Park Junho , Webber Thomas , Shishavan Reza Asgharzadeh , Hedengren John D. 
Published: March 2017

Abstract
Wired Drillpipe (WDP) technology provides two-way and high speed measurements from bottom hole and along-string sensors. The data offered by WDP technology has maximum benefit when applied in an automation system or as a real-time advisory tool. Improved control is demonstrated for Managed Pressure Drilling (MPD) with the use of high-speed telemetry and physics-based models. Stabilizing and minimizing pressure within an acceptable bound leads to higher and more consistent Rate of Penetration (ROP).
MPD control is challenging due to tight pressure windows and the nonlinearity of the choke and pump response on Bottom Hole Pressure (BHP). This work demonstrates a new Hammerstein-Wiener nonlinear model predictive controller for BHP regulation in drilling. Hammerstein-Wiener models employ input and output static nonlinear blocks before and after linear dynamics blocks and thereby simplify the controller design. The control performance is evaluated in scenarios such as drilling, pipe connections, and kick attenuation. A physics-based drilling simulator, WeMod, is used for model identification and control performance evaluation.
The control performance of the new nonlinear controller is compared to conventional controllers in various scenarios. Because of the interconnected multivariable and nonlinear nature of the drilling operation, conventional controllers show severe limitations. In a first scenario, the performance of set point tracking during normal drilling operation is compared. By changing the set point of the BHP, the conventional controller manipulates only the choke valve opening while the nonlinear controller moves choke valve opening, mud pump, and back pressure pump simultaneously. In a second scenario, a pipe connection of a typical drillpipe stand is demonstrated. The conventional controller is not able to regulate the BHP by adjusting the choke valve only. Although a linear version of the controller is able to exploit multivariable relationships, absence of the nonlinear relationships results in severe oscillation when the operational range is shifted outside of the training region. The nonlinear controller maintains a BHP within ±1 bar of the requested set point. A third scenario investigates the kick attenuation performance of conventional and nonlinear control algorithms. The nonlinear controller attenuates the kick within well control conditions, without requiring a well shut-in procedure.
Recent advances in drilling simulators and the reliability of the WDP data highway have enabled tighter BHP control. This study presents a robust method to control BHP by applying Hammerstein-Wiener models in an efficient model predictive controller. The proposed methods have been validated in the downstream industry, but are applied for the first time to drilling with nonlinear control functionality. The multivariable control adjusts three main manipulated variables in MPD simultaneously.
A Case History of the First Drilling with Liner Application in Romania
Authors: Qureshi Ali M. , Rosenberg Steven M. , McGrath Martyn , Tan Ming Zo 
Published: March 2017

Abstract
Drilling a creeping salt formation at a depth of more than 4,200 mMD can be a challenging task, especially when the mud weight cannot be increased enough because of losses in zones above. A stuck pipe can often be released by pumping water pills; however, after drilling through salt while running casing, the hole can close in (time-dependent creep), making it impossible to run casing across this interval. In such situations, innovative ideas to drill and isolate such an interval can help save the day.
One such idea was implemented in a deep well in Romania. While drilling at a depth of 4,237 mMD, the bit encountered an aggressive salt layer, causing stuck pipe that could not be released with water pills and eventually resulted in three sidetracks. On the third attempt, the well was drilled to the top of salt layer, and then the 7-in. liner, a casing bit, and a hydraulic set, rotating liner hanger system were run together on drill pipe. The bit drilled through the 17-m salt layer and died out immediately after achieving its objective. The liner was cemented in place, and the salt layer was successfully isolated. Drilling then continued through the reservoir section below.
This was OMV Petrom's first application of drilling with liner (DwL) and proved to be successful in terms of meeting its objective (i.e., isolating the salt layer). Because the DwL operation was not in the original well design, the DwL system and operating procedures were designed, planned, and delivered on short notice. Considered instrumental to the success of the operation, the collaboration between OMV Petrom and the integrated service provider enabled the engineering and subsequent execution of the DwL operation to move forward in a seamless manner, which contributed greatly to the success of the DwL operation.
The operation proved that DwL can be implemented to case off problematic zones, which increases the likelihood of meeting well objectives. Had this technology not been implemented, the available alternate solution could have resulted in additional time and cost with a low probability of success. This paper will present the experience of the first ever application of drilling with liner in Romania and the associated lessons learned, as well as a discussion of the circumstances under which it became the foremost technology on the way to reaching the target reservoir.
Case History: A Decade of Experience Using Intelligent Completions for Production Optimization and Water Shut-Off in Multilateral Wells in the World's Largest Oilfield
Authors: Dulaijan Auda , Shenqiti Mohammad , Ufondu Kenechukwu , Zahrani Bader , Abouelnaaj Khaled , Shafiq Muhammad 
Published: March 2017

Abstract
Following the success of the first installed intelligent completion system in Saudi Arabia in 2004, over 260 Intelligent Completion systems have been installed in a majority of Maximum Reservoir Contact (MRC) Multilateral (ML) wells. These intelligent completion systems have been successfully installed in openhole, expandable liners, expandable sand screen, Extended Reach Drilling (ERD) wells and also integrated with Electric Submersible Pumps (ESP). This technology has led enhanced oil recovery while reducing water production to surface. Water handling cost at surface is reduced by producing less water to surface and also shutting off downhole water production completely.
This paper covers some of the case histories of over ten (10) years of design, planning, installation, testing and optimization of intelligent completion systems in Multilateral (ML) Maximum Reservoir Contact (MRC) wells within Saudi Arabia. Production optimization practices and enhancement of production life in carbonate multilateral wells in the world's largest oilfield are also documented. Case histories highlighting how water production was remotely choked back, shut-off and production optimized from identified lateral without any intervention in the well are reviewed.
Advantages of intelligent completion technology for multilateral wells and the review of the downhole choke customization process that included design flow area after modelling well data for different flow rates and differential pressures are detailed. This is in addition to the integration of the surface control system to the production supervisory control and data acquisition (SCADA) system which provided real-time downhole pressure and temperature data and remote control of downhole flow control valves during the life cycle of the well. This paper also discusses a closed-loop approach which led to efficient real time production optimization. Performance review of how intelligent completion systems provide selective lateral control, delay water breakthrough, control water production, shut off wet lateral, reduce opex, optimize production, enhance recovery and reduce safety risks thereby minimizing future interventions are documented.
Coiled Tubing Cementing Operation Using MPD Technique in a HP/HT Well
Authors: Mammadov Elvin , Osayande Nadine , Sadat Ali Yousefi , Murtaza Muhammad 
Published: March 2017

Abstract
In the continual search for Oil and Gas, more and more exploration wells are being drilled in High Pressure-High Temperature (HPHT) environments. Pore and Fracture pressure prediction and understanding the true drilling window in HPHT exploration wells poses significant challenges. Once the pressure profile is ascertained, then the next challenge is to drill and cement the well within those limits to avoid kicks, losses and maintain the integrity of the well.
There are special challenges in cementing HPHT wells. These wells typically have a narrow drilling window which could make it very difficult to manage the bottom hole pressure correctly while cementing the open hole section. In any stage of cementing in this type of wells, hydrostatic, dynamic and circulating effects should be considered. These tight windows in HPHT wells, combined with the effect of temperature and pressure on mud density possess significant risks for cementing operation. Also physical and chemical behavior of cement changes in high pressure and temperature. This paper details the advantages of applying advanced Managed Pressure Drilling (MPD) technology during coiled tubing cementing operations in a case study HPHT well. This advanced technique not only allows for maintaining a Constant Bottom Hole Pressure (CBHP) but also reduces the additional costs associated with cement weight and additives. Furthermore, real time flow monitoring eliminates the down hole fluid losses which in conjunction with CBHP reduce formation damage.
A precise managed pressure coiled tubing cementing program was analyzed and planned inclusive of operational procedures and risks management. The well was displaced to a lighter drilling fluid through coiled tubing, while keeping bottom hole pressure (BHP) constant slightly over the formation pressure by applying surface back pressure (SBP). Four different densities of cement slurries were pumped in the hole through coiled tubing and held bottom hole pressure constant during the entire cementing operation within 30 kg/m3 (0.25 ppg) pore pressure and fracture pressure window. Held annular pressure constant with the help of SBP during the eight hours of cement setting time to ensure that hydrostatic pressure would remain in place.
This document demonstrates the successful application of managed pressure coiled tubing cementing operation. It also elaborates the recommended operational procedures, integrated MPD and Coiled tubing equipment setup, along with real-time graphs and data from the case study well.
Overcoming Marginal Load Limits in Small Diameter Tubing Operations by Using Strain Gauge Measurements
Authors: Mehta Atul , Marland Chris , Maharaj Navin , Riise Henrik 
Published: March 2017

Abstract
Because wells are becoming increasingly longer and more complex in trajectory and construction, safe operating limits for running pipe are becoming increasingly smaller. Because of narrow buckling margins in small diameter drillpipe and tubing, an accurate measurement of pipe tension is critical to ensure success when running this pipe. Severe buckling could result in tubing damage or failure, generating potentially significant non-productive time (NPT) or loss of the wellbore. Unreliable surface measurements for hookload and the need to measure minor changes in weights have created a need for the means to measure them. A fully validated and applicable solution is available to overcome these challenges. When run in conjunction with a measurement-while-drilling (MWD) toolstring, including a pressure-while-drilling (PWD) sensor, directional sensor, a controller module and pulser, the tool containing strain gauges provides real-time updates and stores data in memory, with tension readings at the sensor depth, to represent the weight of the string below that point.
This paper presents two cases in which this solution was successfully applied, using strain gauges to measure tension below a point of interest in a string of pipe or tubing in non-drilling applications.
Accurate torque and drag modeling with tripping-in weights and buckling limits plotted against real-time updates from the strain gauge tool provided continuous updates on the load regime downhole. This enabled the tension to be maintained above the buckling limits. Where the tension fell below the limits, remedial actions were taken or operations were carefully continued with extra vigilance for any signs of a deteriorating situation or of string lockup.
The benefits of using strain gauges have been found in yet another non-drilling application described in this paper. Technology to measure tension that has been traditionally used in the improvement of drilling performance can also be applied to improve the performance in activities that pose the challenges of overcoming low operational margins.
Introduction of New Drilling Technology Provides Continuous High Build Rate Capability in Complex Corkscrew Well Trajectory, Accessing Unswept Reserves in the North Sea
Authors: Krueger Stefan , Sharpe Robert , Attridge William , Ruszka Jon 
Published: March 2017

Abstract
In areas of the United Kingdom Continental Shelf (UKCS) operators are progressively seeking to drill increasingly complex well profiles to access un-swept reserves. Wells of such complexity require the introduction of new drilling technology to meet the challenge. In a recent UKCS operation, operator objectives for a wellbore required continuously high rates of curvature and tight dogleg severity control in a soft formation with unconfined compressive strengths (UCS) of 5 to 10 kpsi.
A new, integrated high build-up rate rotary steerable system (RSS), capable of delivering up to 12°/100ft in an 8½-in. hole, was implemented as a solution to achieve and optimize the wellbore placement, thus accessing untapped reserves beneath the offshore platform. In this mature field, collision avoidance with existing wells presented an additional challenge. Focusing on a total system approach, new polycrystalline diamond compact (PDC) drill bit technology was designed to integrate with the high build-up rate (BUR) drilling system. The PDC bit includes features for a smooth torque response, enhanced rate of penetration (ROP), improved durability, and precise steering control. Proprietary software provided confidence in the planning phase that the bit responses, in combination with the deployed steering system and the overall BHA set-up, would deliver the demanding well profile.
This paper presents the details of the integrated drilling technology, as well as the background of pre-drill planning and setup processes necessary for the successful application where no offset experience was available. In addition, this paper details the process management and implementation steps during the service introduction of the new drilling technology. The final performance of the integrated system that drilled the ‘corkscrew’ profile in one drilling run, providing the required well placement and hole quality will be shown. The overall new approach enables the industry to utilize previously inaccessible reserves and drive field economics further.
Successful Application of a New Inertial Steering Mode of Point-the-Bit RSS in Middle East Oilfield
Authors: Li F. , Balka M. , Al-Ghazzawi A. 
Published: March 2017

Abstract
In the past two decades, the point-the-bit rotary steerable system (RSS) has been widely used for high-profile directional drilling jobs in challenging environments, which require accurate directional control. A new inertial steering mode of the point-the-bit RSS was developed by using accelerometers and a rate gyroscope sensor to achieve toolface control in environments, where magnetometers cannot be used for steering. This inertial steering mode effectively expands the operational envelope of point-the-bit RSS by improving its steering ability when magnetic interference, such as drilling out of whipstock window and close to offset wells or ferrous formations, is present or within a Zone of Exclusion (ZOE). Furthermore, the new steering mode can be used as a redundancy scheme in circumstance during magnetometer failures.
Through close collaboration between Research and Development (R&D) and field operation, the inertial steering mode of the point-the-bit RSS has been successfully applied in four wells in Middle East oilfield. In the first well, the new steering mode was used to kick off two 8 3/8" hole sections after setting whipstocks in near vertical wells and it completed the kick-offs in desired directions with accurate toolface control in a high magnetic noise environment. In the second well, the new steering mode was used to exit the casing and drill to TD by using a whipstock. In the third and fourth wells, 12 ¼" hole sections passing through the ZOE were successfully drilled according to the well plan. The application of the new steering mode in these wells saved extra BHA trips, which would have been required if without this new steering mode.
The successful application of the new steering mode in the Middle East oilfield has proven its technical advantages and business benefits.