bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance-Based Tsunami Engineering via a Web-Based GIS Data Explorer
Authors: Keon Dylan ,   Northwest Alliance for Computational Science and Engineering, Oregon State University 2007 Kelley Engineering Center, Oregon State University, Corvallis, OR 97331, USA, Pancake Cherri M. , Steinberg Ben , Yeh Harry ,   ,,   School of Electrical Engineering and Computer Science, Oregon State University, USA,   School of Civil and Construction Engineering, Oregon State University, USA
Published: July 2016

In spite of advances in numerical modeling and computer power, coastal buildings and infrastructures are still designed and evaluated for tsunami hazards based on parametric criteria with engineering “conservatism,” largely because complex numerical simulations require time and resources in order to obtain adequate results with sufficient resolution. This is especially challenging when conducting multiple scenarios across a variety of probabilistic occurrences of tsunamis. Numerical computations that have high temporal and spatial resolution also yield extremely large datasets, which are necessary for quantifying uncertainties associated with tsunami hazard evaluation. Here, we introduce a new web-based tool, the Data Explorer, which facilitates the exploration and extraction of numerical tsunami simulation data. The underlying concepts are not new, but the Data Explorer is unique in its ability to retrieve time series data from massive output datasets in less than a second, the fact that it runs in a standard web browser, and its user-centric approach. To demonstrate the tool’s performance and utility, two examples of hypothetical cases are presented. Its usability, together with essentially instantaneous retrieval of data, makes simulation-based analysis and subsequent quantification of uncertainties accessible, enabling a path to future design decisions based on science, rather than relying solely on expert judgment.
Development of High Precision Tsunami Runup Calculation Method Based on a Hierarchical Simulation
Authors: Arikawa Taro ,   Chuo University 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan, Tomita Takashi ,   ,,   Nagoya University, Nagoya, Japan
Published: July 2016

The 2011 Great East Japan Earthquake (GEJE) has shown that tsunami disasters are not limited to inundation damage in a specified region, but may destroy a wide area, causing a major disaster. Evaluating standing land structures and damage to them requires highly precise evaluation of three-dimensional fluid motion – an expensive process. Our research goals were thus to develop a coupling STOC method [1] and CADMAS-SURF/3D [2] to efficiently calculate all stages from tsunami source to runup and to verify their applicability. We confirmed the method’s accuracy by computing in the Onagawa District during the GEJE and comparing results to observed data. We also investigated the stability of buildings.
Tsunami Effects on Buildings and Coastal Structures
Authors: Yeh Harry ,   Oregon State University Corvallis, Oregon, 97331, USA, Sato Shinji ,   ,,   University of Tokyo, Tokyo, Japan
Published: July 2016

In 2011, the Heisei Tsunami (also known as the East Japan Tsunami) caused unprecedented damage to well-engineered buildings and coastal structures. We examine two reinforced concrete buildings that were exposed to similar tsunami loadings, but one collapsed and the other did not. It is shown that the contrast is partly resulted from the presence of a building foundation that could cause a time delay and attenuation of the buoyancy effect on the buildings. The surviving building must be stabilized by the weight of water that flooded the building interior. We also investigate failure patterns of concrete seawalls and coastal dykes. It is demonstrated that flow-induced suction pressures on the crown play a role in the failure of concrete panels that covered the dyke’s infill. High-speed flows together with high compressing pressures can cause the formation of a scour at the leeside foot of the dyke. Considerations for the design guidelines for buildings and coastal structures to cope with the “beyond-the-design-basis” extreme coastal hazards are proposed.
Dynamic Response Differences Between Bedding and Counter-Tilt Rock Slopes with Intercalated Weak Layers
Authors: Zhi Song ,   Chengdu Institute of Geology and Mineral Resources  No.1, The north 3, Yang Liu ,   Section of First Ring Road, Chengdu, Sichuan, China,   ,,   School of Civil Engineering, Southwest Jiaotong University, China
Published: July 2016

Bedding and counter-tilt rock slope with intercalated weak layers are common geological bodies in west China, the dynamic response research will guide the anti-seismic reinforcement of bedding and counter-tilt rock slope with intercalated weak layer effectively. Two test models of bedding rock slope with intercalated weak layer and counter-tilt rock slope with intercalated weak layer, which are in the same size, have been designed and developed. A large scale shaking table test has been performed to analyze the dynamic response difference of bedding and counter-tilt rock slope with intercalated weak layer. The study results show that the acceleration amplification coefficient inside the bedding slope is smaller than that inside the counter-tilt rock slope; at the middle and upper parts of the slope body (relative height > 0.4), the acceleration amplification coefficient at bedding rock slope surface is larger than that of counter-tilt rock slope. At the lower part of the slope (relative height le 0.4), the acceleration amplification coefficient at bedding rock slope surface is close to that of counter-tilt rock slope. The slope surface displacement of both bedding and counter-tilt rock slopes increases with increasing input seismic wave amplitude. The slope surface displacement of the bedding rock is larger than that of counter-tilt rock slope. The seismic stability of counter-tilt rock slope is stronger than bedding rock slope. The dynamic failure form of bedding rock slope mainly includes vertical tension crack at back edge, bedding sliding along intercalated weak layer and rock collapse at slope crest; whereas the dynamic failure form of counter-tilt slope mainly includes intersection of horizontal and vertical cracks on slope surface, extrusion of intercalated weak layer and shattering of slope crest.
Modifying Business Continuity Plan (BCP) Towards an Effective Auto-Mobile Business Continuity Management (BCM): A Quantitative Approach
Authors: Montshiwa Abednico Lopang ,   Graduate School of Engineering, Tohoku University 661180 Aza-Aoba-ku, Sendai, Miyagi 980-8579, Japan, Nagahira Akio , Ishida Shuichi ,   ,,   Graduate School of Technology Management, Ritsumeikan University, Osaka, Japan
Published: July 2016

Traditionally BCP consists of two main aspects, being Business Impact Analysis (BIA) and Risk Assessment (RA) [3,,8]. However, this approach doesn’t seem to be sufficiently addressing the complex and elaborate nature of supply chain network in the automobile industry. To address this insufficiency, we replace RA with Risk Ranking (RR) and introduce a new term Supply Chain Cooperation (SCC) to our BCP. A quantitative study was carried on 75 automobile parts markers in disaster prone regions (Asia and North America) and the results were analyzed by adopting this modified BCP concept and using Smart PLS 2.0 as our statistical analysis tool. We realized that SCC has a positive total significant effect on manmade risk rankings, natural risk ranking and BCM. Though risk ranking affects BCM, recovery time and competitive advantages positively, the relationships were not significant. In this study, we realized that BIA is the single most important part of BCP as it had the strongest positive total effects on other BCP factors (SCC, manmade risk ranking and natural risk ranking), BCM and evaluation factors (competitive advantages and recovery time).
Science Communication of Hazards with Scientific Uncertainty: In the Cases of Volcanic Activity
Authors: Kuri Miwa ,   International Research Institute of Disaster Science, Tohoku University  6-6-11 Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8578, Japan,   ,
Published: July 2016

This paper studies cases in Japan, focusing on information on volcanic activities as well as other natural disasters. This information is given as an example of scientific communication in times of scientific uncertainty when there is an urgent need for judgments. This paper also considers the usage of volcanic activity information by residents of Kuchinoerabu Island in 2015, from the time their volcano became active to when the island was fully evacuated. The results suggest that it is important not only to establish relationships with highly interested local residents as non-experts, residents who can communicate information, including uncertainties, but also to communicate information among experts, government bodies, and designated members the news media. It is also suggested that a cooperative system of geoparks that feature disasters and benefits would help the volcanic disaster prevention council.
Spatial-Temporal Assessment of Debris Flow Risk in the Ms8.0 Wenchuan Earthquake-Disturbed Area
Authors: Yao Xin ,   Institute of Geomechanics, Chinese Academy of Geological Sciences Key Laboratory of Neotectonic Movement and Geohazards, Ministry of Land and Mineral Resources No.11, South Road of Nationality University, 10086, Haidian District, Beijng, China, Li Lingjing ,   ,
Published: July 2016

For 5 years (2009–2013) after the 2008 Ms8.0 Wenchuan earthquake, rainfall led to the transformation of unconsolidated co-seismic deposits into extensive and severe debris flows, causing significant loss of life and property. For debris flows in the earthquake-disturbed area, a few common concerns exist. What is their spatial-temporal distribution? What are the controlling factors? How much is the rainfall threshold for debris flows? What areas are more susceptible? Where suffered the most severe losses of life and property? Using debris flow characteristics, this study analyzes the relationships between seismic geological factors, geomorphologic factors, extreme rainfall, and debris flows in the 5 years following the earthquake, and draws the following conclusions. (1) There are regional differences in the rainfall threshold for generation of debris flows, and the annual maximum 72-hour accumulated rainfall for triggering a debris flow decreases from pre-seismic periods (135–325 mm) to post-seismic periods (75–160 mm) by 44.4–50.8% in study area. (2) Areas with high debris flow susceptibility and hazard are primarily controlled by seismic geological conditions. (3) The long-term risk of debris flows will fall to moderate, and the affected area will shrink to that around the seismogenic fault. The results of this study will help with meteorological early warning systems, deployment of disaster prevention and control projects, and reconstruction site selection in the post-seismic Longmen Mountain area.
A New Method for the Estimation of Lost Gas During the Measurement of the Gas Content of Coal
Authors: Lu Meng , Pan Zhejun , Connell Luke D. , Lu Ye
Published: July 2016

In this text, the authors present a study on estimating the lost gas during the retrieval process of coal sample within wellbores. A new method is proposed because the traditional ones often give inaccurate predictions. To this end, the major sources of errors with those routine methods are first discussed briefly, and modifications are made accordingly in the present method to improve the accuracy of prediction. This new method takes into account these aspects: (1) Both the advection and diffusion effects are included in the proposed flow equation; (2) the present model uses the actual shape of the core sample (say, a cylinder) rather than a simplified 1D spherical object; and (3) a fully numerical scheme is developed in which the actual retrieval history is used to specify the boundary conditions of the core sample. When the relevant sorption isothermal curve for the coal is known, the proposed model contains three parameters to be determined, which refer to the effective permeability, the effective diffusion coefficient, and the initial gas content or the initial gas pressure. The three parameters are determined through best matching the experimental data with the aid of an artificial-neural-network (ANN) technique. Two application examples are presented in this study. One is with a benchmark laboratory test, and the other is with a standard field case studied by means of an established method. It is shown with the two examples that the present method can give accurate predictions for the lost gas volume concerned, and offers some important advantages that the traditional ones do not have.
Rheology Modification for Safe Cementing of Low-ECD Zones
Authors: Gahlawat Ravinder , Jandhyala Siva Rama , Mishra Vaishali , Patil Sandip
Published: August 2016

Long-term zonal isolation requires effective mud displacement. One best practice for achieving this is to use the highest pumping rates allowable during cementing operations. However, in zones with a narrow pressure window, fracture pressure sometimes does not support higher flow rates. This is because high flow rates result in high friction pressures, which can exceed the fracture pressure of the formation. This is an issue particularly in long horizontal wells. In such cases, fluid rheology is important for achieving better displacement efficiency without inducing fractures.

The current work discusses a procedure in which the rheology of cement slurry can be tuned such that good displacement efficiency is attained at sufficiently low flow rates. The tuning should be such that the shear stress is almost invariant for varying shear rates. This reduces the friction pressures considerably during placement. A hydraulics model was run on an example well configuration with a narrow margin situation. Pressure response and displacement characteristics of two types of slurries were analyzed. These include conventional and modified slurry, the latter of which was tuned for better mud displacement at low flow rates.

The modified slurry showed an increase in yield point with a shear stress profile that was almost invariant for the range of shear rates analyzed. A decrease in equivalent circulating density (ECD) occurred as a result of rheology modification, and this resulted in avoiding ECDs exceeding the fracture gradient at critical locations. Displacement efficiency increased by 10% when using the modified slurry at the same pump rates as those used for the conventional slurry. On the other hand, when targeting the same displacement efficiency as the conventional slurry, the required pump rates for the modified slurry were lower.

This study indicates that better displacement can be attained through rheology modification, even by using relatively low flow rates, thereby maintaining low ECDs to help ensure effective cementing operations.
Appropriate Completion To Prevent Potential Damage of Annular Pressure Buildup in Deepwater Wells
Authors: Zhang Bo , Guan ZhiChuan , Wang Qing , Xuan LingChao , Liu Yongwang , Sheng Yanan
Published: August 2016

Deepwater oil and gas wells will generate annular pressure due to the redistribution of wellbore temperature in production stage when the hyper-thermal fluid is lifted from reservoir formation. Annular pressure threatens casing integrity and well safety. Related accidents have been reported in Mexico Gulf, South China Sea and some other deepwater oilfield. The analysis indicates that annular pressure buildup is so high that deepwater well is in the risk of casing collapse, so it is necessary to take some measures to mitigate annular pressure. Since subsea wellhead is unable to release pressure, appropriate completion measures must be considered. Good understanding of mechanism as well as accurate calculation is prerequisite for appropriate completion, so a model is built based on comprehensive consideration of multi-string interaction and heat transfer process to offer basic pressure data for well completion.

According to Annular Pressure Build-up mechanism, pressure can be controlled by releasing expanded liquid out or getting extra space to accommodate liquid as well as slowing down increasing speed of annular liquid temperature. Some completion technologies can work as mitigation measures. These mitigation methods can be divided into two types: active and passive. Active methods function through increasing heat-transfer resistance or eliminating annulus, including full-height cementing, heat-insulated liquid, thermal-insulated pipes and reducing production rate. Passive methods mitigate pressure build-up by releasing some extra space to contain expanded fluid, including cement shortfall, rupture disc, compressible foam and highly compressible annular fluid. These measures differs at cost, operating difficulty, reliability and working mechanism. Among them, thermal-insulated Pipes, heat-insulated liquid, compressible foam, rupture disc, increase the annular liquid compressibility possess good applicability and have been applied in some wells or tested through experiments. Considering deepwater wells' structure, this paper analyzes the feasible measures and offer design methods.
A Comprehensive Survey Management Workflow
Authors: Schiermeier Pete , Greenwood Jeremy
Published: August 2016

To ensure the highest level of accuracy in wellbore placement, the integration of many survey management techniques is required, which in certain situations includes the integration of relative wellbore position measurements (ranging). The goal is to identify and eliminate all errors and biases that are internal and external to the survey tool to help reduce the positional uncertainty of the wellbore and to determine the relative position of the current wellbore to surrounding wells.

Designing a workflow to achieve the necessary combination of analyses to cover all potential situations required the development of an application that allows an expert user to select and configure the appropriate corrections. It had to be easy to use and provide empirical solutions to the wellsite users in a timely manner to help limit rig interruptions and associated nonproductive time (NPT). Rigorous workflow analysis is required to ensure a high level of quality for the final surveys to meet industry expectations for well positioning and also criteria from governing bodies that demand the final well position be formally recorded.

Current practice involves multiple steps for survey correction, beginning with basic quality assurance and increasing in complexity by identifying instrument biases in accelerometer and magnetometer readings, compensating for local magnetic and gravity anomalies in the subsurface, identifying interference generated by ferromagnetic materials in the drillstring itself and surrounding wells, and compensating for diurnal fluctuations in the earth's magnetic field caused by changes in the intensity of solar radiation. Each of these corrections involves different data sources, from the raw responses of the measurement devices to time-based magnetic observatory data, and the cumulative effect of all of these factors should be determined as accurately as possible to help minimize uncertainty.

The workflow seamlessly combines all of the different correction methodologies currently available and allows the automation of the calculations after they have been configured by the expert. Multiple wells can be assessed concurrently, increasing the amount of time the expert spends on analysis and interpretation and reducing the time required to obtain and manipulate data.

This workflow is unique to the industry because it combines every survey correction methodology available, enabling the analysis of all potential environments and resulting in greater accuracy. Accurate determination of the wellbore position should significantly reduce health, safety, and environment (HSE) risks associated with the potential for wellbore collisions caused by the inherent uncertainty of the wellbore location and can significantly improve reservoir production through optimum placement.
A Semi-Empirical Carbonate Acidizing Model for Chelating-Agent-Based Fluids
Authors: Baghel Vikesh Singh , Pravesh Jag
Published: August 2016

This study investigates, theoretically and experimentally, the effect of conventional and new chelating-agent-based acidizing fluid systems on carbonate formations. An initial assessment showed that an existing semi-empirical model used for hydrochloric (HCl) acid systems was not suitable for predicting wormhole growth and penetration for chelating agents.

With recent advances to acidizing and stringent environmental regulations, chelating agents have begun to replace conventional acid systems for well stimulation. They are more environmentally acceptable and can work in high-temperature wells. One crucial aspect for successful well stimulation of carbonate matrix acidizing is acidizing models. Yet, there have been few attempts to model wormhole growth and penetration for these newer chelating agents.

A semi-empirical mathematical model is proposed for chelating agents based on published experimental data. The results were compared with HCl acid systems.

The predicted wormhole growth was in good agreement with laboratory data for a wide range of temperatures and concentrations. A comparative study with chelating-agent and HCl-acid systems is also discussed. Results showed that pore volume to breakthrough (PVbt) for the chelating-agent-based system increased more steeply compared to the HCl-acid-based system with injection rate. This would translate into higher pumping volumes in the field for a given wormhole penetration if not optimized. This could be attributed to the slower reaction rate of the chelating agent and might require adjustment in transport phenomena for optimized treatment design.

The model developed in this work should help field engineers design treatments with optimum rates and volumes, helping minimize the cost of stimulation treatments. It should also further facilitate understanding of the wormhole formation mechanism for chelating agents.
Using MPD Techniques to Effectively Drill Differently Pressured Layered Sand Reservoirs on Deepwater Development Wells Offshore Malaysia
Authors: Pinkstone H. , Doll R. , Chandra M. , Babcock W. , Tilley V. , Choo B.
Published: August 2016

Previous offset wells drilled in the layered sandstone differentially pressured reservoir formations offshore Malaysia in 1341m water depth, using conventional open system drilling techniques, had experienced lost drilling fluid circulation and hydrocarbon gas kick events, resulting in significant non-productive drilling time, and well control events.

This paper describes how advanced Managed Pressure Drilling (MPD) technology, combined with a drill string conveyed subs based (CCS) continuous circulation system, were deployed on a tender assist semi-submersible rig, and used to effectively and safely drill subsequent development wells. Techniques employed on the project also included Dynamic MPD Well Control and Formation Evaluation procedures, along with dynamic Managed Pressure Cementing (MPC) techniques.

MPD and CCS systems were used, along with MPC, to effectively drill and complete sandstone reservoir layers at various formation pressures depleted from ongoing production, and also over pressured layers charged as a result of water injection activity.
Improving Oil Recovery in Complex Heterogeneous Reservoirs of Highly Mature Oil Fields through Innovative Measurement and Strategies: A Case Study from South China Sea
Authors: Wu Yiming , Zhang Yongjiang , Wang Chao , Chang Botao
Published: August 2016

Located in South China Sea, B oil field has entered into mature development phase. A horizontal drilling campaign was initiated to develop the remaining oil reserve within the heterogeneous reservoirs with multiple laminated layers.

To address the challenges and uncertainties of drilling horizontal wells in these complex reservoirs, an innovative approach and strategy were introduced and employed for optimal well placement in a specific heterogeneous reservoir. This approach includes the advance distance-to-boundary mapping service and the high-definition multiboundary mapping service with the ability to map multiple key boundaries within reservoirs.

Best practices have been developed for using this innovative approach in strategic planning and real-time well placement of horizontal wells in the field for the efficient draining of the reservoir. These include the description of the detailed reservoir profile, the sweet zone identification while drilling, and the lateral placement close to the sweet zone top to minimize the attic oil and extend the well life. The outcomes in two successful wells were: ■Clear identification of multiple boundaries of the reservoir geobodies and their interfaces including the current fluid contact level.■Minimization of attic oil and achieving optimum lateral placement to drain the reservoir.■Exceeding the economic prediction of heterogeneous reservoirs

The successful implementation of the innovative well placement strategy in complex and heterogeneous fields will lead to extended production, optimal well economics, and increased oil recovery. The approach provides an example of using integrated technology solutions to overcome the challenges in complex reservoirs with multiple laminated layers.
An Innovative Pipe Grade to Enhance Reach of Deeper Prospects in Sour Fields
Authors: Plessis Guillaume J. , Uttecht Amie , Pink Tony , Hehn Lucien , Jellison Michael J. , Vinson Barry
Published: August 2016

Moving into the next decade, wells in the Middle East are becoming more challenging as the deeper and more complex plays are exploited. This environment will be challenging from a torsional and tensile loading standpoint, and will be dynamically very active. This type of environment combined with high levels of H2S calls for a new high grade of sour service pipe. The Middle East is also opening up to the idea of high speed telemetry and wired pipe economics that call for a long lasting pipe product.

When using sour service pipe that is traditionally limited to 105 KSI grades, even with an optimized string design, drillers sometimes have no other option than to sacrifice the margin of overpull, risking losing the well if fishing is unsuccessful. Alternatively, they can elect to use drill pipe, which is not suited for use in this corrosive environment, generally using API S135, with a risk of parting the string due to H2S embrittlement. To address these operational limitations, the pipe body, which is the drill pipe limiting member in tension, has to come with higher material strength and at the same time exhibit improved Sulfide Stress Cracking (SSC) resistance compared to API S135 grade.

A novel grade of drill pipe was developed over a period of two years that is the strongest sour service drill pipe the industry has to offer to date and gives drillers an extra 19% of tensile capacity with its 125 KSI material yield strength. This new grade has been ordered for use in various regions of the world and for numerous applications. At this time, it is being used for intervention and stimulation operations in the Gulf of Mexico (GOM), and drilling long, extended reach (ER) wells with wired telemetry drill pipe in the Middle East.

This paper presents the phases of the grade development and discusses testing requirements for the crossover between strength and SSC resistance. It also includes statistical data on the first full scale manufacturing tests. Finally, it outlines the products expectations for field applications.
Employing Process, Benchmark Automation, and Real-Time Analysis to Improve Drilling Efficiency
Authors: Taylor Aimee , Wesley Avinash , Adari Ram , Kurian Lijoy
Published: August 2016

Using the right offset well data to plan the next project is critical, but performance expectations get diluted when metrics are averaged over large depth ranges. Focusing on the rate of penetration (ROP), a benchmarking process was developed to improve drilling efficiencies. The whole process was automated and included a real-time analysis of the well being drilled that was capable of quickly identifying the 1) offset wells based on location, lithology, well type, and performance; 2) sectors within those wells with common formation, wellbore, and tubular characteristics; and 3) the effective technical limit (ETL)—the best drilling performance that realistically can be repeated. The process mentioned in this paper identifies opportunities for operators to reduce inefficiencies while drilling, allowing users to take action while there is still opportunity to mitigate or eliminate the damage.

Using the guided workflow and real-time data to identify and select the appropriate offset wells, multiple ETL sectors are created based on the characteristics they share (formation, wellbore, tubular). During real-time operations, when the same set of characteristics for a particular sector is met, ETL data for that sector are displayed, and users can evaluate performance in real time compared to best historical performance. This paper also presents a case study in which this process was applied to improve an operator's drilling efficiency.
Mechanical Specific Energy for Drilling Optimization in Deepwater Brazilian Salt Environments
Authors: Pinto C. N. , Lima A. L.
Published: August 2016

Operators exploring presalt areas report issues with bottomhole assembly (BHA) wear and failure resulting from factors such as vibrations, stick-slip, and torsional resonance during drilling operations in salt layers. This study presents a new real-time analysis based on geomechanics capability to optimize energy consumption and rate of penetration (ROP) in salt-layer drilling and improve economic results.

A real-time geomechanical analysis based on mechanical specific energy (MSE) was used to optimize drilling and prevent nonproductive time (NPT) when drilling in evaporite intervals. This analysis defined two energy limits as a function of depth. Both maximum and minimum energy limits were calculated in real time based on estimates of confined compressive strength and intrinsic MSE, respectively. The intrinsic MSE calculation depends on the mechanical properties of the rocks [i.e., unconfined compressive strength (UCS), friction angle (θ), and the cutting environment].

When both limits were estimated, a real-time analysis was successfully developed based on measuring and comparing the following: MSE applied during the drilling process, which depends on drilling parameters, such as ROP, rev/min, weight on bit (WOB), and torqueMSE intrinsic valuesConfined compressive strength (CCS) of the evaporate

The analysis identified excessive energy consumption to help reduce and mitigate factors, such as axial/lateral vibrations, stick-slip, torsional resonance, and wear of BHA components in this geological environment. All factors were estimated and analyzed through empirical relations based on logging while drilling (LWD) logs and mud logging parameters.

Results of two case studies show how excess energy results in excessive vibrations and wear of the BHA when this energy analysis is not applied and energy stabilization, ROP efficiency, and mitigated vibrations when the methodology is implemented. A depth versus time plot shows drilling performance optimization with 12 operational days saved and no operational NPT registered. Economic results were also positive.

This study aims to create a methodology that helps optimize the ROP in real time for salt environments based on the estimation of the minimum and the maximum (optimum) values of energy necessary to drill efficiently and avoid BHA failures resulting from excess energy in the drilling system.
Innovative Approach Helps Operator Drill Faster and Achieve Benchmark ROP Over Offset Runs in Southern Kuwait
Authors: Baqer Yousef Ahmed , Eid Khaled , Ebrahim Ebrahim Khalil , Ghoneim Osama , Jokhi Ayomarz , Hassan Said , Nair Prakash , Helal Karim
Published: August 2016

Drilling the 12¼-in hole in southern Kuwait usually starts in a shale formation and continues through interbedded sandstone, limestone, and shale. The unconfined compressive strengths throughout the section vary from 6,000 psi to 10,000 psi. The bit types typically used in this section are six-bladed PDC bits with either 16-mm or 19-mm cutters. Because fields in the area are development fields, the main objective for the operator is to achieve the best rate of penetration (ROP) and complete the section as quickly as possible. A common objective was decided on between the operator and bit provider to design a bit to drill the 12¼-in section in one run with ROP above the current benchmark.

Different design configurations with different blade counts, cutter sizes, and cutting structures were analyzed using dynamic simulation based on finite-element analysis (FEA). The simulations were run in a dynamic environment to arrive at a design suitable to drill the application. The cutters were designed to withstand excessive wear, enabling the cutters to stay sharper for a longer interval and drill faster relative to previously used bits until the end of the run. Once the suitable bit was designed, different parameters were run in the simulation to define a set of parameters to be applied while drilling the actual well.

The offset wells had delivered ROP in the range of 83–93 ft/h. The new design drilled the entire section in one run in 8.7 hours, attaining an ROP of 108.6 ft/h. This represents an ROP improvement of 18% over the benchmark ROP, setting a new benchmark ROP for this application.

A combination of changing the bit configuration and cutter type along with the optimized cutting structure enabled the bit to last longer and drill faster than previous bits, saving the operator the cost for the associated drilling hours.
Contraceptive use in Hungary: Past trends and actual behavior
Authors: Makay Zsuzsanna
Published: August 2016

In the present study I look first at findings of earlier surveys on women’s birth control behavior since 1958 in Hungary. I then turn to the detailed analysis of the birth control practices of Hungarian women based on data from the Generations and Gender Survey (2008–2009). First I examine the influences on whether partnered women of reproductive age employ any birth control methods or not, and then I explore the methods that are chosen. What emerges from this examination is that modern contraception has spread widely in Hungary since the 1960s, but in 2009 a quarter of Hungarian women were still not using any method of birth control, or else they were merely using a traditional low-efficiency types. The profile of such abstainers is clear: they are reaching the end of their reproductive period, have a low level of education, are married, have financial difficulties, are generally childless, and do not plan to have a child in the short-term. The results of a multinomial logistic model show that there are also several demographic and social factors behind choosing a method of contraception. In 2009 the most common of these was the condom, followed by birth control pills (“the Pill”) and intra-uterine devices (IUDs, “the coil”). Finally, the study compares birth control in five European countries and its changes since the 1990s. The use of the Pilldeclined in all the countries in the 1990s, and only in Bulgaria and Hungary have condom users outnumbered pill-takers.
Aplicación del algoritmo de optimización metaheurístico BOA en el diseño de PSSs robustos para sistemas de potencia multimáquina
Authors: Ramírez González Miguel , Castellanos Bustamante Rafael , Calderón Guizar Jorge Guillermo
Published: July 2016

Se presenta la aplicación del algoritmo de optimización BOA (de las siglas en inglés para Bat Optimization Algorithm) en el diseño robusto de estabilizadores de sistemas de potencia (PSSs por sus siglas en inglés) en sistemas multimáquina. Con el fin de amortiguar las oscilaciones electromecánicas del sistema, la sintonización de parámetros de los PSSs involucrados se efectúa de manera coordinada mediante la alternativa de optimización propuesta y la minimización de una función objetivo calculada directamente de simulaciones en el dominio del tiempo. La efectividad y robustez de los PSSs propuestos (BOAPSSs) es investigada a través de la simulación del sistema de estudio bajo diferentes condiciones de operación y perturbaciones. El desempeño de los BOAPSSs es comparado tanto con la respuesta de PSSs diseñados convencionalmente como con el comportamiento proporcionado por PSSs basados en algoritmos genéticos y en optimización de enjambres de partículas. Los resultados obtenidos de este estudio muestran un desempeño notablemente superior de los PSSs propuestos con respecto a los PSSs diseñados convencionalmente. Así mismo y en comparación con PSSs basados tanto en algoritmos genéticos como en inteligencia de enjambres, se verifica la mejora en el comportamiento dinámico del sistema al utilizar los PSSs diseñados con la metodología propuesta.
Hongos micorrízicos arbusculares como agentes mitigadores del estrés salino en plántulas de albahaca
Authors: Aguero-Fernandez Yuneisy Milagro , Hernández-Montiel Luis Guillermo , Nieto-Garibay Alejandra , Troyo-Diéguez Enrique , Zulueta-Rodríguez Ramón , Murillo Amador Bernardo
Published: July 2016

En la naturaleza las plantas se encuentran expuestas a diversas condiciones de estrés que retardan su desarrollo y disminuyen su rendimiento. Uno de los problemas agrícolas más extendidos es la acumulación de sales en la superficie del suelo o la salinización del agua para riego. El objetivo del estudio fue evaluar un consorcio de hongos micorrízicos arbusculares (HMA) de las especies Funeliformis mosseae y Claroideoglomus etunicatum como posibles mitigadores del estrés por NaCl en plántulas de variedades de albahaca en la etapa de emergencia. Se utilizó un diseño completamente al azar con arreglo factorial. El factor 1 fueron tres variedades de albahaca (Nuffar, Genovese y Napoletano), el factor 2 fueron tres niveles de estrés salino (0, 50 y 100 mM de NaCl) y el factor 3, los hongos micorrizicos arbusculares (0 –control- y 1 g del inoculo) con cuatro repeticiones de 30 semillas cada una. Se evaluó la composición química del sustrato y del inóculo utilizados, la tasa y porcentaje de emergencia, altura de plántula, longitud de raíz, biomasa fresca de parte aérea y de raíz y porcentaje de colonización. Los resultados mostraron que tanto el sustrato como el inóculo utilizados fueron adecuados para el desarrollo de las especies de HMA evaluadas y para la especie vegetal en estudio. Ninguna de las raíces de las plántulas de las variedades en estudio mostraron presencia de vesículas, arbúsculos y/o hifas cenocíticas. Todas las variables presentaron valores superiores en aquellas plántulas cuyas semillas se inocularon con HMA. Las variedades mostraron diferencias para la mayoría de las variables evaluadas, siendo Napoletano superior, mientras que Genovese mostró lo contrario. La mayoría de las variables disminuyeron sus valores conforme las concentraciones de NaCl incrementaron.
Evaluation of CMPA precipitation estimate in the evolution of typhoon-related storm rainfall in Guangdong, China
Authors: Wang Dashan , Wang Xianwei , Liu Lin , Wang Dagang , Huang Huabing , Pan Cuilin
Published: July 2016

The merged precipitation data of Climate Prediction Center Morphing Technique and gauge observations (CMPA) generated for continental China has relatively high spatial and temporal resolution (hourly and 0.1°), while few studies have applied it to investigate the typhoon-related extreme rainfall. This study evaluates the CMPA estimate in quantifying the typhoon-related extreme rainfall using a dense rain gauge network in Guangdong Province, China. The results show that the event-total precipitation from CMPA is generally in agreement with gauges by relative bias (RB) of 2.62, 10.74 and 0.63% and correlation coefficients (CCs) of 0.76, 0.86 and 0.91 for typhoon Utor, Usagi and Linfa events, respectively. At the hourly scale, CMPA underestimates the occurrence of light rain (<1 mm/h) and heavy rain (>16 mm/h), while overestimates the occurrence of moderate rain. CMPA shows high probability of detection (POD = 0.93), relatively large false alarm ratio (FAR = 0.22) and small missing ratio (0.07). CMPA captures the spatial patterns of typhoon-related rain depth, and is in agreement with the spatiotemporal evolution of hourly gauge observations by CC from 0.93 to 0.99. In addition, cautiousness should be taken when applying it in hydrologic modeling for flooding forecasting since CMPA underestimates heavy rain (>16 mm/h).
The significance of spatial variability of rainfall on simulated runoff: an evaluation based on the Upper Lee catchment, UK
Authors: Pechlivanidis I. G. , McIntyre N. , Wheater H. S.
Published: July 2016

The significance of spatial variability of rainfall on runoff is explored as a function of catchment scale and type, and antecedent conditions via the continuous time, semi-distributed probability distributed model (PDM) hydrological model applied to the Upper Lee catchment, UK. The impact of catchment scale and type is assessed using 11 nested catchments, and further assessed by artificially changing the catchment characteristics and translating these to model parameters (MPs) with uncertainty using model regionalisation. Dry and wet antecedent conditions are represented by ‘warming up’ the model under different rainfall time series. Synthetic rainfall events are introduced to directly relate the change in simulated runoff to the spatial variability of rainfall. Results show that runoff volume and peak are more sensitive to the spatial rainfall for more impermeable catchments; however, this sensitivity is significantly undermined under wet antecedent conditions. Although there is indication that the impact of spatial rainfall on runoff varies as a function of catchment scale, the variability of antecedent conditions between the synthetic catchments seems to mask this significance. Parameter uncertainty analysis highlights the importance of accurately representing the spatial variability of the catchment properties and their translation to MPs when investigating the effects of spatial properties of rainfall on runoff.
A laboratory experimental system for infiltration studies
Authors: Morbidelli Renato , Saltalippi Carla , Flammini Alessia , Cifrodelli Marco , Corradini Corrado
Published: July 2016

The investigation of a few hydrological processes under natural conditions can be distorted by their interactions. In this context, a laboratory system that allows a few mechanisms of the infiltration process to be studied univocally is presented. The core component of the system is a physical model consisting of a soil tank with slope angle, γ, adjustable from 1 ° to 15 °. A generator of artificial rainfall can produce rainfall rates up to 50 mm h−1. Surface runoff and deep flow, Qd, are continuously monitored. An overall analysis of three previous investigations performed by the physical system and directed to clarify the infiltration process is also briefly reported. These investigations, that concerned the validation of a local conceptual model for erratic rainfalls, the role of run-on and the effects of sloping soil surfaces, were all carried out by using different configurations of the system. Great slope effects in bare soils were observed. For example, under steady conditions, a ratio Qd(γ = 1°) / Qd(γ = 10°) equal to about 4 was observed in a loam soil. Finally, on the basis of the acquired knowledge, further investigations to be realized with the same basic elements are proposed to derive a conceptual model that describes the soil surface gradient effects.
DRASTIC assessment of groundwater vulnerability to pollution in the Vistula floodplain in central Poland
Authors: Krogulec Ewa , Trzeciak Joanna
Published: July 2016

Assessment of groundwater vulnerability to pollution was conducted by the DRASTIC method in central Poland, in the Vistula River valley. The results of this study have shown that 68.18% of the study area has a low pollution potential and 31.2% has a medium pollution potential. Single-parameter and map removal sensitivity analyses were conducted to evaluate the relative importance of the parameters for aquifer vulnerability. Both analyses showed that by far the most significant parameter of the DRASTIC vulnerability index in the study area is the depth to the water table. Although the water table in more than 90% of the study area is shallow, less than 3 m below ground level, the assessment shows that this does not lead to a high groundwater vulnerability.
Surface flows from images: ten days of observations from the Tiber River gauge-cam station
Authors: Tauro Flavia , Salvatori Simone
Published: July 2016

Fully remote surface flow measurements are crucial for flow monitoring during floods and in difficult-to-access areas. Recently, optics-based surface flow monitoring has been enabled through a permanent gauge-cam station on the Tiber River, Rome, Italy. Therein, a system of lasers and an internet protocol camera equipped with two optical modules afford video acquisitions of the river surface every 10 minutes. In this work, we establish a standard video-processing protocol by analyzing more than 10 Gb of footage data captured during low discharge regime from May 2nd to 11th, 2015, through particle tracking velocimetry (PTV). We show that good image-based velocity data can be obtained throughout the day – from 6 am to 8 pm – despite the challenging experimental settings (direct sunlight illumination, mirror-like river surface, and overlying bridge shadow). Further, we demonstrate that images captured with a 27° angle of view optical sensor lead to average velocity measurements in agreement with available radar data. Consistent with similar optical methods, PTV is not applicable in case of adverse illumination and at night; however, it is more robust for dishomogeneous distributions of floaters in the field of view.
α-Glucosidase Inhibitory Effect and Antioxidant Activity of the Extracts of Eighteen Plant Traditionally Used in Algeria for Diabetes
Authors: Khacheba Ihcen , Boussoussa Hadjer , Djeridane Amar , Bekhaoua Abir , Bensayah Noussiba , Yousfi Mohamed
Published: August 2016

Background:

This paper focuses on one of the most recurrent hypotheses
for the antidiabetic effect of medicinal plants by inhibiting the alpha -glucosidase

Objective:

In the present study aqueous and hydro -alcoholic extracts of eighteen
medicinal plants, collected in the town of Laghouat in the steppe region of Algeria,
and which are used in the treatment of diabetes, were examined for α-glucosidase
inhibition using an in vitro model. Also total phenol content and antioxidant activity
of the extracts was investigated.

Methods:

The extracts were prepared using distilled water and hydro -alcoholic solvent
(methanol/water). The amount of total phenolics and flavonoids in the samples
was determined with the Folin-Ciocalteu reagent and with aluminum chloride respectively. To identify
plants with inhibitory capacities, we have studied the effects of ours extracts on the kinetics catalyzed of
α-glucosidase an enzymes belonging to the class of hydrolase responsible for the digestion and we have
subjected our extracts to inhibition assay to determine the inhibition percentage for each extract. Finally,
we assessed the potential antioxydant of the best inhibitory plants with the DPPH test.

Results:

The major plants were found to inhibit enzymatic activity of α-glucosidase and the values of
the IC50 constants have been determined for the best inhibitory plants common in both extraction methods
(Cistus SP, Salvia officinalis and Zygophylum album), with values ranged from 0.38 to 28.95
mg/ml. The evaluation of antioxidant activity of this plants using DPPH test, shows that the phenolic
extract of Salvia officinalis exhibit good antioxidant capacity (8.46 μg/ml) comparatively to the antioxidants
taken as reference (BHA, Gallic acid, Rutin, Trolox and Vitamin C).

Conclusion:

This study is the first report on potential inhibition of these plants extracts on the digestive
enzyme, α-glucosidase. The obtained results support the traditionally use of a number of the analyzed
species in the in the management of diabetes.