bluuebunny/crossref_metadata_2025_split huggingface dataset:
Buffering Syndemic Effects in a Sexual Risk-Reduction Intervention for Male Clients of Female Sex Workers: Results From a Randomized Controlled Trial
Authors: Pitpitan Eileen V. , Strathdee Steffanie A. , Semple Shirley J. , Chavarin Claudia V. , Magis-Rodriguez Carlos , Patterson Thomas L. 
Published: February 2015

Objectives. We sought to test the efficacy of a sexual risk intervention for male clients of female sex workers (FSWs) and examine whether efficacy was moderated by syndemic risk. Methods. From 2010 to 2014, we conducted a 2-arm randomized controlled trial (60-minute, theory-based, safer sex intervention versus a didactic time-equivalent attention control) that included 400 male clients of FSWs on the US–Mexico border with follow-up at 4, 8, and 12 months. We measured 5 syndemic risk factors, including substance use and depression. Primary outcomes were sexually transmitted infections incidence and total unprotected sex with FSWs. Results. Although participants in both groups became safer, there was no significant difference in behavior change between groups. However, baseline syndemic risk moderated intervention efficacy. At baseline, there was a positive association between syndemic risk and unprotected sex. Then at 12 months, longitudinal analyses showed the association depended on intervention participation (B = −0.71; 95% confidence interval [CI] = –1.22, –0.20; P = .007). Among control participants there still existed this modest association (B = 0.36; 95% CI = –0.49, 1.22; P = .09); among intervention participants there was a significant negative association (B = −0.35; 95% CI = –0.63, –0.06; P = .02). Conclusion. A brief intervention might attenuate syndemic risks among clients of FSWs. Other populations experiencing syndemic problems may also benefit from such programs.
A Nanoscale Simulation Study of Elastic Properties of Gaspeite
Authors: Benazzouz Brahim-Khalil 
Published: February 2015

Abstract
The study of structural and mechanical properties of carbonate rock is an interesting subject in engineering and its different applications. In this paper, the crystal structure of gaspeite (NiCO3) is investigated by carrying out molecular dynamics simulations based on energy minimization technique using an interatomic interaction potential.
At first, we focus on the structural properties of gaspeite mineral. And then, the elastic properties are calculated, including the elastic constants, bulk modulus, shear modulus, the S- and P-wave velocities. In the next part of this paper, the pressure effect will be studied on the structural and elastic properties of NiCO3 at high pressure.
State of Strength in Massive Concrete Structure Subjected to Non-Mechanical Loads
Authors: Łydźba Dariusz , Sobótka Maciej 
Published: February 2015

Abstract
The paper deals with an impact of non–mechanical loads on the state of strength in massive concrete hydraulic structures. An example of hydroelectric plant subjected to the effect of water temperature annual fluctuation is considered. Numerical analysis of transient thermal–elasticity problem was performed. After determining the temperature distributions within the domain, the Duhamel-Neumann set of constitutive equations was employed to evaluate fields of mechanical quantities: displacement, strain and stress. The failure criterion proposed by Pietruszczak was adopted in assessing whether the load induces exceeding of strength of concrete within the structure volume. The primary finding is that the temperature effect can lead to damage of concrete in draft tubes and spirals, especially in winter months.
Behaviour of Cohesive Soil Subjected to Low-Frequency Cyclic Loading in Strain-Controlled Tests
Authors: Kalinowska Marta , Jastrzębska Małgorzata 
Published: February 2015

Abstract
The subject of the paper comprises tests of cohesive soil subjected to low-frequency cyclic loading with constant strain amplitude. The main aim of the research is to define a failure criteria for cohesive soils subjected to this type of load. Tests of undrained cyclic shear were carried out in a triaxial apparatus on normally consolidated reworked soil samples made of kaolinite clay from Tułowice. Analysis of the results includes the influence of number of load cycles on the course of effective stress paths, development of excess pore water pressure and stress deviator value. Observed regularities may seem surprising. The effective stress path initially moves away from the boundary surface and only after a certain number of load-unload cycles change of its direction occurs and it starts to move consequently towards the surface. At the same time, it has been observed that pore water pressure value decreases at the beginning and after few hundred cycles increases again. It is a typical behaviour for overconsolidated soil, while test samples are normally consolidated. Additionally, a similar change in deviator stress value has been observed - at first it decreases and later, with subsequent cycles, re-increases.
Comparative Model Tests of SDP and CFA Pile Groups in Non-Cohesive Soil
Authors: Krasiński Adam , Kusio Tomasz 
Published: February 2015

Abstract
The research topic relates to the subject of deep foundations supported on continuous flight auger (CFA) piles and screw displacement piles (SDP). The authors have decided to conduct model tests of foundations supported on the group of piles mentioned above and also the tests of the same piles working as a single. The tests are ongoing in Geotechnical Laboratory of Gdaňsk University of Technology. The description of test procedure, interpretation and analysis of the preliminary testing series results are presented in the paper.
Technical Note: Stability of a Levee Made of Bottom Sediments From a Dam Reservoir
Authors: Koś Karolina , Zawisza Eugeniusz 
Published: February 2015

Abstract
Stability analysis of a levee made of the bottom sediments from Czorsztyn-Niedzica Reservoir is presented in the paper. These sediments were classified as silty sands and, based on the authors' own research, their geotechnical parameters were beneficial, so the possibility of using this material for the hydraulic embankments was considered. Stability and filtration calculations were carried out for a levee that had the same top width - 3 m, slope inclinations 1:2 and different heights: 4, 6 and 8 m. Two methods were used: analytical and numerical. Calculations were carried out without and with a steady and unsteady seepage filtration. Based on the analysis carried out it was stated that the levee made of the bottom sediments is stable even at the height of 8.0 m, although because of the seepage on the downstream side it is recommended to use a drainage at the toe of the slope.
L'accouchement par césarienne, un risque pour les droits reproductifs ?
Authors: Brugeilles Carole 
Published: February 2015

La possibilité d’accoucher par césarienne est souvent associée à l’amélioration de la santé de la reproduction et au respect des droits qui lui sont associés. Dans les pays du Sud, elle est rarement pratiquée dans certains contextes, ce qui est préjudiciable à la santé et ne garantit pas les droits reproductifs, alors que dans d’autres, sa fréquence élevée suscite des controverses. Cet article propose de discuter les relations complexes de l’accouchement par césarienne avec la santé et les droits reproductifs. L’utilisation massive de la césarienne représente-t-elle une limite à la santé reproductive et une entrave à l’exercice des droits reproductifs ? L’analyse est fondée sur une synthèse bibliographique de références principalement médicales, épidémiologiques et de santé publique, les sciences sociales étant relativement en retrait sur cette question. Une attention particulière est portée à l’Amérique latine, sous-continent très concerné par « l’épidémie de césariennes ».
New Guideline for Seismic Assessment of Fixed Facilities in Malaysian Water
Authors: Mukherjee Kaushik , B Ayob M Sapihie , Khai Lai Tze , Nichols Nigel Wayne 
Published: February 2015

A large part of the fleet of platforms in Malaysian waters are ageing with the increasing demand of enhancement in view of further oil recovery and the additional development in the extended and nearby field. The enhancement process will also require development of new facilities to comply with performance and integrity requirements. The integrity issues imposed thus needs to be dealt with multi-disciplinary efforts that include a fresh regional seismic hazard mapping. To address this, a site specific assessment was carried out in 2009 for Sabah, Sarawak and West Malaysia offshore concessions in the South China Sea. The study concluded that the use of standard ISO spectral maps to be unconservative for the seismotectonic conditions offshore Malaysia. A modified spectrum shape, generally consistent with the ISO 19901–2 had been developed to match expected ground motion in each of the three blocks.
To formalize this, a new guideline has been developed for the seismic assessment of existing platforms as well as newly built fixed structures in Malaysian region.
The impact of the modified spectrum was assessed and recorded for selective platforms in these regions. This, in combination with the newly developed framework of adopting Performance Based Design, will form a complete guideline closely aligned with Petronas performance target and HSE expectations.
Fundamentally, offshore platforms shall have adequate strength against all effects influencing their structural integrity. The seismic requirements are intended to reduce risks to persons, the environment and assets to the lowest level that are reasonably practicable. The technical aspects of the developed seismic criteria can easily be implemented in future designs. However, understanding of the effect on the fitness-for-purpose of the existing structures in line with the ISO requirements are also essential. Particular emphasis to be given to the systematic inspection and subsequent integrity of topside connections of the existing facilities.
Unlocking the Potential of Metal Oxides Nanoparticles to Enhance the Oil Recovery
Authors: Hendraningrat Luky , Torsaeter Ole 
Published: February 2015

The development of current technology has enabled manufacturer to create various types of nanoparticles for multi-purposes in various sectors including the oil and gas industry. The use of nanoparticles for enhanced oil recovery (EOR) has been studied in the past decade both in the lab- and pilot-scale projects. Most of the research observed that nanoparticles are very attractive for EOR purposes. However, most of those studies use ??of silica-based nanoparticles. The use of other types of nanoparticles should be investigated as alternative solution.
In this study, two water-based metal-oxides nanoparticles: Al2O3 and TiO2, were employed. The primary size of both nanoparticles ranged of 40-60 nm. Nanofluids was prepared by dispersing 0.05 wt.% metal-oxides nanoparticles with synthetic saline water. Berea sandstones cores are used as porous media with average porosity and permeability of 15% and 60 mD respectively.
Coreflood experiment was conducted by injecting metal-oxides nanofluids as tertiary process (Nano-EOR). Degassed crude oil with viscosity ranged 5–50 cP was also used. To investigate the effect of temperature and rock wettability to oil recovery, coreflood experiment has been performed on various temperature condition and initial cores wettability: water-wet, intermediate-wet and oil-wet.
The detailed process and results are outlined in the paper to reveal the possible application of metal-oxides nanoparticles as alternative EOR method.
Free Span Rectification by Pipeline Lowering (PL) Method
Authors: Thusyanthan N.I. , Sivanesan K. , Murphy G. 
Published: February 2015

Surface laid pipelines experience free spans due to various reasons such as uneven seabed, local scour or a storm event. If free span lengths are beyond acceptable limits, vortex induced vibrations (VIV) can cause the pipeline to undergo fatigue damage and severely reduce the pipeline's design life. Thus pipelines need to be periodically monitored to ensure that there are no free spans that are beyond the acceptable length. When such free spans are identified, these need to be rectified immediately to avoid fatigue damage to the pipeline. Rectifying unacceptable free spans in existing pipelines are a constant battle for operators around the world.
Free spans on existing pipelines are commonly rectified by grout bags. While this method is considered to be a standard and cheap solution, it often does not provide a long term solution to free spans. It is often the case that the pipeline whose free spans are rectified by grout bags needs further free span rectification the following year. The onset of more free spans and the need for rectification cycle often continues annually when grout bags are used to rectify free spans.
This paper presents a new approach named the "Pipeline lowering (PL) method" for free span rectification. This unique solution will ensure the free span rectification is a long term solution compared to grout bags that may be affected by scour and wave loadings. The solution involves lowering the crests of the free spans such that the pipeline follows the natural seabed profile while ensuring the pipeline integrity is not compromised at any stage. The lowering operation is carried out solely by fluidizing the seabed soil by a mass flow excavator and the pipeline lowers under its self-weight. A laboratory demonstration and successful field implementation of PL method for free span rectification are presented in this paper.
This paper provides vital technical knowledge on free span rectification by PL methodology for pipeline engineers, contractors and operators who need to ensure free spans are rectified safely and efficiently. This new methodology is a cost effective and elegant solution.
A New Method Of Bhp Measurement In Esp Deadhead Test
Authors: Xian Wei , Wenyu Liu , Yan Pi 
Published: February 2015

The Electric Submersible Pump (ESP) intake pressure and well bottom-hole pressure are important factors in reservoir management and well performance optimization. Normally, the bottom-hole pressures for ESP wells are determined by ESP sensors, slick line pressure gradient technique or acoustic sounding technique. However, there're still some wells' ESPs have no sensor (or sensor failed); and acoustic or slick line operations can't be run due to the well bore restrictions.
This paper develops a method of measuring bottom-hole static and flowing pressure by variable ESP speed for these wells. And it is a quick way to get the pressure data without shut-in operation and can be operated at low cost. The theory of the method is the "Affinity Laws" of centrifugal pump. The centrifugal pump heads will change as the square of speed variation. And with a deadhead test under different ESP speed conditions, the bottom-hole pressure can be calculated.
There are around 80 ESP artificial lift wells in the case field at Bohai bay. All of these wells produce with ESP and sensor installed. However around 13% sensors are failed due to misc. reasons. Reservoir management became complicated because unable to get the exact reservoir pressures.
By the method given by paper, after the authors get the deadhead pressure data, comparison has been done with sensors had reading pressure in 12 wells. Authors also tested 11 sensor failed wells' downhole pressure and successfully optimized wells' performance.
Simulation Protocol for Core Flooding: Relative Permeability and Capillary Pressure Analysis
Authors: Kumar S , Awang Mariyamni , Abbas Ghulam , Farouque Khurram , Ahmed Sheraz 
Published: February 2015

The relative permeability and capillary pressures are used to characterise large-scale multiphase flow encountered in recovery of hydrocarbons. These parameters are acquired via special core flooding experiments. Reservoir engineers calculate these parameters from special core analysis (SCAL) module of reservoir simulation. However, core flooding is an expensive experiment and involves spending lot of time and efforts before Darcy law assumptions are achieved. Therefore, independent simulation of core flooding is necessary during which reservoir engineers can perform faster and simultaneous analysis of relative perms and capillary pressures of multiphase flow.
This paper presents 1-D black oil simulation of core flooding using Sendra software to get relative perms and capillary pressures. The approaches used in this study are four steps. In the first step, the results of core flooding were estimated at different correlations. In the second step, experimental data of core flooding for differential pressure and production versus time were referenced in the software. Then history matching was performed using estimated and experimental data of core flooding using different correlations. Based on this, the best fits of correlations were obtained for estimating both relative perms and capillary pressures. The benefits of this approach compared with other methods are that it saves time, user-friendly and faster. It is reliable for estimating relative permeability and capillary pressures at steady state or unsteady state, imbibitions or drainage process either in oil or gas recovery.
A Case Study Detailing the Design, Planning, Installation and Cost and Environmental Benefit Analysis of a Reinforced Thermoplastic Pipe Pulled Through the Inside of an Existing Offshore Steel Flow Line in the East Malaysia Samarang Field
Authors: Wright John R , Karim Khairul Anuar , Kennedy Steve 
Published: February 2015

There are many older offshore steel pipelines that have been damaged or exhibit excessive corrosion whereby dropping below minimum wall thickness requirements. Conventional rehabilitation or replacement of existing offhshore flow back lines often times has been cost prohibitive for older lower producing wells resulting in the premature abandonment or closing of wells.
By pulling flexible reinforced thermoplastic pipes through the existing steel pipelines and multiple riser configurations, signifcant cost savings can be realized with minimal sea floor disturbance. The reduced capital costs allow wells to continue to be productive through their remaining lives without sacrificing pipeline integrity. This paper provides a detailed case study for a Petronas flow line in the Samarang Field describing the step by step processes required for a successful rehabilitation of a pipeline. This includes proper pipe sizing considerations to compensate for lower flow rates, material selection for the reinfoced thermoplastic pipe to withstand the pipleline flow environment, determination of pull force requirments, regulatory approvals, pre-installation preparation of the existing flow line, step by step installation procedures, testing and integrity requirements and how unforseen issues raised durning the process were addressed. The paper will conclude with lessons learned and what improvements were implemented for future projects as well as the cost benefits versus replaceing the steel lines
Simulation Study for Smart Horizontal Wells Application in Maximizing Oil Reserves for Malaysian Field EOR Thin Oil Reservoir
Authors: Metwally M.M. , Faizal M. , B A Rashid R. , Rizal M. 
Published: February 2015

Abstract
Horizontal wells become an important factor in improving well productivity, especially in brown-field development. Smart well completions are becoming the best in development technology with horizontal wells. Inflow control devices (ICD) are used to enhance the performance of the horizontal wells by delaying gas and water breakthrough. However, as smart completions make the horizontal well more expensive, so their use requires justification. Reservoir simulation studies are very helpful tools to optimize and evaluate the number, size and locations of the ICD along the horizontal section. This paper presents a simulation and optimization study which was carried out on the planned three horizontal infill wells in one of Malaysian field. The infill wells will be subjected to enhanced oil recovery (EOR) scheme after almost five years from their initial production. The EOR scheme will include drilling more gas and new water injectors in order to support the reservoir pressure. Application of the EOR scheme emphasizes need of using ICD to balance the expected gas and water production. The main target of the study is to properly model the horizontal wells with ICD completion using the multi segmented well approach. Several simulation runs were evaluated to cover the expected scenarios for the required ICD design. All results were compared to the case assuming production without using ICD. This is to observe the benefits of using ICD and to come up with the optimized ICD design suitable for each well. The study is crucial firstly, in evaluation of the initial simulation results of ICD application before drilling of the planned wells and secondly to have a proper ICD design model for each horizontal well which can be quickly modified in future based on the actual data during drilling operations where there is no more time available for the rig.
The Use of Dope-Free Tubulars in Offshore Operations: Experiences and Benefits
Authors: Actis Goretta Emiliano , Castineiras Tomas , Giacomel Bruno , Merliahmad Mustaffa 
Published: February 2015

The use of Dope-Free tubulars in offshore operations have been increasingly adopted by different operators since its debut in the North Sea in 2003.
Dope-Free tubulars replaces the storage and running pipe dope historically used in Casing and Tubing by a dry coating applied on pipe threads in an industrial controlled environment.
The elimination of dope simplifies greatly the supply chain of the preparation of Casing and Tubing for offshore increasing the efficiency, safety and lessening the environmental impact of the process.
The main benefits of this technology are: - Improved Operational efficiency - preparation, running, pulling management of rig returns; - Reliability: connections are installed in a more consistent and repetitive manner as the coating is an industrial process replacing a manual operation; - Improve well productivity: eliminating the damage to the formation created by the pipe dope and Health Safety & Environment.
Operators experience, after a short learning curve, showed great reductions in installation time, reduction on connections re-make ups and rejects, improvement on workers' Health & Safety conditions by eliminating unsafe tasks and creating cleaner work areas, and minimization of the Environmental impact.
This paper describes the experiences and benefits of the use of Dope-Free tubulars in offshore operations in the main offshore oilfields including the North Sea, the Barents Sea, Brasil, Indonesia, Gulf of Mexico and the Persian Gulf.