bluuebunny/crossref_metadata_2025 huggingface dataset:
Diversity and genetic structure in natural populations of Geonoma schottiana Mart (arecaceae): implications for conservation
Authors: Silva Mirian de Sousa , Vieira Fábio de Almeida , Carvalho Dulcinéia de
Published: September 2014

Geonoma schottiana is an underbrush palm which is found in high densities in tropical forests. This species is known for having an asynchronous fruit producing pattern, over all seasons of the year, thus being an important food source for frugivores. This work aims to determine the diversity and spatial genetic structure of two natural populations, referred to as MC I and MC II, of which 60 individuals were sampled, in Poço Bonito Biological Reserve, Lavras, Minas Gerais state. Results of 10 polymorphic isozyme loci indicated a high genetic diversity for the species (Ĥe= 0.428 and Ĥo = 0.570), with an mean number of alleles per locus of 2.0. Estimates of Cockerham's coancestry coefficients indicated an absence of intrapopulation ( or = -0.343) and interpopulation inbreeding ( or = -0.161), suggesting that on average populations are not endogamous. A high genetic divergence was found between populations ( = 13.5%), in comparison to most tropical species (<5%). Consequently, the estimated historical gene flow was low (m = 0.40). The analysis of spatial distribution of G. schottiana genotypes in MCI revealed a random distribution of genotypes. The high genetic diversity indices found suggest that the populations in question favor in situ genetic conservation, consequently favoring the conservation of riparian environments.
Análise de custos da implantação de cultivos de eucalipto em áreas acidentadas no sul do Espírito Santo
Authors: Carmo Flávio Cipriano de Assis do , Fiedler Nilton César , Guimarães Pompeu Paes , Pereira Daniel Pena , Andrade Wendel Sandro de Paula
Published: September 2014

Objetivou-se, por meio desta pesquisa, realizar uma análise de viabilidade econômica de cultivos de eucalipto em empreendimentos apoiados pelo fomento florestal, caracterizando os custos das operações de implantação, manutenção, colheita semimecanizada e transporte rodoviário de madeira em área com topografia acidentada no sul do Espírito Santo. Foi calculada a viabilidade econômica do projeto pelo valor presente líquido (VPL), taxa interna de retorno (TIR) e custo médio de produção (CMP), para os seguintes cenários de produtividade: 140,00; 180,00; 220,00; e 250,00 m³/ha. De acordo com os resultados encontrados, o produtor teve um custo total de R$ 10.381,24; R$ 11.306,59; R$ 12.115,79; e R$ 12.722,69/ha para cada cenário analisado. O empreendimento não foi viável para a produtividade mínima de 140,00 m³/ha (VPL de -R$ 127,14/ha, TIR de 8,16% e CMP de R$ 58,29/m³) e foi viável para as produtividades acima de 180,00 m³/ha. O cenário de produtividade de 250,00 m³/ha apresentou os melhores indicadores: maior VPL (R$ 2.412,14/ha), maior TIR (17,24%) e menor CMP (R$ 40,83/m³).
Variação radial da densidade básica e dimensões celulares da madeira de Cariniana legalis (Mart.) O. Kuntze em função da procedência
Authors: Lima Israel Luiz de , Longui Eduardo Luiz , Garcia Michelle Fonseca , Zanatto Antonio Carlos Scatena , Freitas Miguel Luiz Menezes , Florsheim Sandra Monteiro Borges
Published: September 2014

Testes de procedência podem fornecer informações sobre o comportamento silvicultural e qualidade da madeira para a exploração da variabilidade e a conservação de material genético para usos futuros. Neste trabalho, objetivou-se estudar a variação radial da densidade básica e dimensões celulares da madeira de procedências de Cariniana legalis plantadas em Luiz Antonio SP. Mudas de três procedências (Porto Ferreira, Piracicaba e Campinas) foram plantadas em Luiz Antonio-SP, utilizando-se seis repetições em delineamento experimental de blocos casualizados. Após 26 anos do plantio, abateram-se dezoito árvores, seis de cada procedência. Foram estudadas a densidade básica e dimensões celulares da madeira. De acordo com os resultados, pode-se concluir que densidade básica, comprimento das fibras, espessura da parede das fibras, comprimento dos elementos de vaso, diâmetro de vasos, altura e largura de raios unisseriados foram influenciados pela procedência. Foi observada uma relação positiva entre comprimento das fibras, espessura da parede das fibras, comprimentos dos vasos, diâmetro dos vasos e altura de raios multisseriados com a posição radial e uma relação negativa entre a frequência de vasos com a posição radial.
IziNambuzane: IsiZulu names for insects
Authors: Cockburn Jessica J. , Khumalo-Seegelken Ben , Villet Martin H.
Published: September 2014

We provide a tool for communicating about insects in isiZulu to facilitate research and knowledge sharing in the fields of indigenous knowledge, cultural entomology, environmental education and community extension involving isiZulu speakers. A total of 213 different names for 64 insect specimens were encountered among a sample of 67 respondents in 11 communities distributed across the province of KwaZulu-Natal, South Africa. This list includes 93 names that can be considered core isiZulu vocabulary and which are widely used to identify insects that are agriculturally, medically, domestically, culturally or ecologically common or significant. Substantial variation was found regarding the names for particular insects, especially between regions, suggesting dialectal differences between isiZulu speakers. Grammatical and social variation in names was also recorded. This study highlights interdisciplinary teamwork in the field of indigenous knowledge research and the influences affecting the standardisation of South African languages for technical and scientific work.
Open access in South Africa: A case study and reflections
Authors: Czerniewicz Laura , Goodie Sarah
Published: September 2014

In this paper, we locate open access in the South African higher education research context where it is, distinctively, not shaped by the policy frameworks that are profoundly changing research dissemination behaviour in other parts of the world. We define open access and account for its rise by two quite different routes. We then present a case study of journal publishing at one South African university to identify existing journal publishing practices in terms of open access. This case provides the springboard for considering the implications – both positive and negative – of global open access trends for South African – and other – research and researchers. We argue that academics’ engagement with open access and scholarly communication debates is in their interests as global networked researchers whose virtual identities and online scholarship are now a critical aspect of their professional engagement.
Energy demand and reduction opportunities in the UK food chain
Authors: Tassou Savvas A. , Kolokotroni Maria , Gowreesunker Baboo , Stojceska Valentina , Azapagic Adisa , Fryer Peter , Bakalis Serafim
Published: September 2014

The food chain comprises agricultural production, manufacturing, distribution, retail and consumption. In the UK it involves approximately 300,000 enterprises, it employs 3ṡ3 million people and accounts for £188 billion in consumer expenditure. The food chain is also responsible for 18% of total UK energy use, 176 MtCO2e emissions and 15 Mt of food waste. Estimates of energy consumption and emissions from the food chain vary between sources, primarily due to differences in the assumptions made, but the general consensus is that reduction in energy consumption and resource use in the food sector is not only vital for the profitability of the sector but also for food security and meeting the Government's greenhouse gas emissions reduction targets. This paper reviews the literature on energy consumption and emissions from each stage of the food sector and outlines approaches and technologies for demand reduction. It will provide the basis for further refinement of the estimates and development of methodologies and projects to effect significant reductions of energy and resource use as part of the End Use Energy Demand Initiative of Research Councils UK.
On the role of grain shape in static liquefaction of sand–fines mixtures
Authors: WEI L.M. , YANG J.
Published: September 2014

This technical note presents new experimental evidence for the role of grain shape in the static liquefaction behaviour of sand–fines mixtures. The laboratory experiments comprise a series of strain-controlled triaxial tests on several types of sand–fines mixtures that are intended to clarify a concern remaining in a previous study by the same authors: whether the observed effect of grain shape was due to the differences in hardness of the added fines. The comparison of new test results with the previous ones confirms that it is grain shape rather than grain hardness that is responsible for the observed differences in overall behaviour. Adding fines of rounded shape into a clean sand indeed results in a marked increase of liquefaction potential compared with adding fines of more angular shape into the same sand. It is also shown that the concept of the combined roundness is effective and useful for quantifying in an integrated manner the influence of grain shape and fines content on the overall friction angle of sand–fines mixtures at critical state.
Reducing Cost and Deferred Production in Sucker Rod Pumping Well Subjected to Intermittent Steam Cycling Utilizing Steam ByPass Pump in PDVSA West
Authors: Argüello V. J. , Ramirez P.. , Jimenez B.. , Hernandez D.. , Nuñez S.. , Caldera N..
Published: September 2014

The demand of heavy oil production is a challenge by the petroleum industry to develop, through new technology, and improved methods of pumping heavy oil producing wells. The "Steam ByPass" (SBP) pumps consists of a mechanical pump that operates in heavy oil-producing wells, subjected to cyclic steam stimulation (CSS), it allows the passage of steam without removing the pump from the well; additionally introduces enhancements and accessories to prevent the deposition of solids and damage to internal components during the injection phase that cause premature failure.

Actually in PDVSA West the process to cyclic steam injection with down hole pumping was carried out by annulus (casing - tubing) which could cause problems, such as: casing deterioration, lower quality steam, pumping premature failure (anchor, cage, and balls), loss or inefficiency of the steam cycles.

The high rate of failure of pumps, after the cyclic steam injection, it has originated the search for an alternative which increase or maximize the run life of pumps subjected CSS.

The evaluation of the "Steam ByPass" pump had been used in two (02) wells of Lagunillas field in PDVSA West and has obtained reduction of production deferred after CSS (in order to 100%), as well as reducing work over (almost two) during a regular process or to cause premature failure. These two tests has showed that the SBP pump overcoming the time average durability of pumps subjected to similarly process and demonstrated it is operational performance.
Improved Artificial Lift Design for Solvent Assisted SAGD Processes
Authors: Babayemi Babatunde , Wu Xingru , Sharma Suresh
Published: September 2014

Artificial lift design for heavy oil systems is a continual changing process in which evolving technological advancements coupled with constant learning experience has led to production capabilities that were not feasible in the past. There has been an increase in installation of temperature tolerant Electric Submersible pumps (ESP) with the primary aim of improving deliverability from mature heavy oil fields. Similarly, in the heavy oil industry, the desire to attain energy efficiency has birthed variations of the Steam Assisted Gravity Drainage (SAGD) process that use solvent additives in further reducing bitumen viscosity. The heavy oil emulsion formed in these systems exhibit rheological characteristics and outflow behaviors different to conventional SAGD systems. Tubing hydraulic performance, steam trap requirements and flow assurance behaviors associated with production from these systems are investigated in this work.

This paper presents dynamic multiphase simulations detailing fluid flow regimes, mass and heat transfer mechanisms and pressure/temperature changes as the reservoir fluid flows out of the reservoir, through an ESP and up the production tubing to the surface. The reservoir is a 3D fully coupled reservoir/wellbore model with properties similar to the Athabasca bitumen reservoir. The simulation was conducted considering all periods in the lifecycle of production i.e. pre and post ramp up. This research finds that a detailed understanding of fluid phase behavior and reservoir operating parameters during the different periods can dramatically improve operating efficiency and impact on ESP design.

Furthermore, results generated from this research can be used as a yardstick for SAGD production engineers in designing artificial lift systems for solvent assisted processes
Progressing Cavity Pump Sizing: Black Magic or Science?
Authors: Dunn Lonnie , Prakash Abhishek
Published: September 2014

Progressing cavity (PC) pumps deployed as an artificial lift method have seen their range of use expand from their heavy oil origins in Canada to a wide variety of different applications around the world. This expansion has been enabled by the development of new products to meet the different volume, lift and downhole fluid environment requirements. However the effect of the fluid environment on the PC pumps‘ stator elastomeric lining dimensions and properties and, in turn their impact on pump performance and life, introduces a critical application design consideration. This consideration is commonly referred to in the industry as pump sizing and encompasses the process of adjusting rotor dimensions to compensate for the impact of the downhole environment on the stator.

Pump sizing started as a trial and error approach based on pump functional testing. As the fluid environments began to have an increased impact on the stator elastomer, pump sizing came to be recognized as being important to ensuring pump success. Methods for measuring rotors and stators were improved and calculation and sizing methodologies developed. Pump test bench equipment and processes became more sophisticated and their accuracy and reliability improved. Methods for laboratory testing elastomer samples in well fluids were developed to quantify dimensional and mechanical property changes.

The second edition of the ISO 15136-1 International Standard for PC Pump Systems for Artificial Lift¹ provides guidelines for component measurement, pump testing and elastomer compatibility testing but does not address the use of this information for pump sizing. Consequently pump sizing is currently done differently across the industry with limited information being provided to end users. This often results in confusion and poor implementation and can detrimentally affect PC pump performance and runtimes. In extreme cases it has led to the characterization of PC pumps as being unsuitable for a particular application when the problem was primarily with the pump sizing. This paper provides an overview of the historical and current state of the different processes associated with PC pump sizing and shows how the newer processes can be applied in a systematic scientific manner to support the successful application of PC Pumps.
Evaluation and Optimization of Proppant Distribution in Multistage Fractured Horizontal Wells: A Simulation Approach
Authors: Bokane Atul , Jain Siddharth , Crespo Freddy
Published: September 2014

Multistage hydraulic fracturing has become the key technology for completion of horizontal and vertical wells. The perf and plug method is the most commonly used staging method. During each stage, multiple perforation clusters are used, attempting to create a separate transverse fracture at each cluster. How these clusters are placed can significantly affect both short- and long-term production performances. Simultaneous creation of multiple fractures is a cost-effective and time saving method for stimulating both vertical and horizontal wells. Multistage fracturing is an effective method in terms of completion efficiency; however, achieving even proppant distribution to each cluster is an intricate task that can be challenging within the industry.

Numerical simulations predict uneven proppant distribution of the fluid streams entering different perforation clusters. Field data indicates, in many cases, that some of the clusters do not contribute to production. This led to hypothesizing that actual proppant and fluid distribution along the stimulated clusters can differ from the assumed uniform distribution.

This paper presents an extensive optimization study and investigation of proppant transport in different perforation clusters within a single stage using computational fluid dynamics (CFD) techniques. Effects of proppant and fluid properties (e.g., variable mass flow rate, variable proppant and fluid densities, and viscosity of the fluid) were analyzed, while maintaining outside-casing parameters constant. Validation of empirical proppant transport CFD simulation results are compared to experimental test data.

The CFD results indicate that proppant transport can be accurately modeled when the effects of single particle settling, density driven flow, particle velocity profiles, and slurry rheology are all considered. Understanding the behavior of proppant and achieving more even proppant distribution among perforation clusters can help the industry. The investigation demonstrates that CFD is an effective tool for optimizing proppant distribution among perforation clusters and enhancing production.
Development of Specialized Plots for Production Data Analysis of Tight Reservoirs with Secondary Fractures
Authors: Ezulike O. D. , Dehghanpour H.
Published: September 2014

Many fractured horizontal wells are completed in tight oil/gas or shale gas reservoirs which have significant networks of interconnected secondary fractures (SF). However, the existing linear transient dual- and triple-porosity models do not properly account for SF. While the dual-porosity model assumes negligible SF, the linear sequential triple-porosity model assumes negligible fluid transfer between the rock matrix and hydraulic fractures. Hence, the application of these models for production data analysis of fractured horizontal wells could result in unreasonable reservoir/fracture parameter estimates and hydrocarbon forecast. For this reason, the quadrilinear flow model (QFM) was developed to account for matrix—hydraulic fracture communication. Although QFM properly accounts for the contribution of SF during reservoir depletion, reservoir parameter estimation from its type-curve matching procedure has a high degree of uncertainty. This paper proposes simplified QFM flow regime equations to reduce the uncertainty associated with reservoir parameter estimation.

This study carefully analyzes the general QFM solution by observing the flow regions from dimensionless rate and pressure type-curves. This solution is simplified by eliminating dimensionless parameters with negligible contribution to fluid depletion within the duration of each flow region. The resulting simplified equations are analytically inverted from Laplace space to time space. The simplification process 1) yields flow-region analysis equations for the specialized rate-normalized pressure and pressure derivative plots and 2) explains the possible physics behind the flow-regions.

The effect of secondary fracture networks on reservoir depletion can be investigated by applying QFM analysis equations on specialized rate-normalized pressure and pressure derivative production data plots. The choice of these plots is based on operational well constraints and observable flow regions. The analysis equations are applied to interpret production data of two multifractured horizontal wells completed in the Cardium and Bakken Formations. The results estimate effective half-length of hydraulic fractures, investigate the presence/absence of secondary fractures and propose a workflow for handling the uncertainty in reservoir parameter estimation when applying the specialized analysis equation plots.
Integration of Microseismic Data, Tracer Information, and Fracture Modeling into the Development of Fractured Horizontal Wells in the Slave Point Formation
Authors: Roney Dana , Quirk David , Ziarani Ali S. , Burke Lyle
Published: September 2014

The tight carbonate platform portion of the Slave Point has seen tremendous development over the last few years through application of multi-stage hydraulically fractured horizontal wells. Higher oil prices and depleting conventional resources have motivated operators to focus on this once by-passed resource. One of the primary engineering challenges is the optimization of the fracture size, geometry and conductivity along the length of a horizontal well. Tight reservoirs are marked by significant initial decline rates and many operators are now looking to a combination of fracture optimization and enhanced oil recovery (EOR) schemes to offset decline rates and increase the EUR. Understanding the performance and connectivity of the hydraulic fractures is a significant input to EOR design and performance.

In this study, sixteen stages of microseismic data collected from two wellbores were used to constrain fracture geometries. These geometries were then integrated with pumping operations, mini-frac / DFIT analysis, and log data to create a calibrated fracture model in a pseudo-3D fracture simulator. The objectives of the calibrated fracture model were to better understand the resultant fracture production performance as well as options to optimize fractures and improve hydrocarbon recovery.

Chemical tracers were included in each stage of the fracturing fluid (water). This allowed for fluid flow back to be analyzed in an attempt to understand which portions of the wellbore are more productive than others.

This paper presents a case study of the workflow to integrate the microseismic, fracturing, reservoir and tracer studies in order to optimize the understanding of the hydrocarbon production.
The Application of Discrete Fracture Network Modelling to the Optimization of Wells in Resource Plays
Authors: Emsley Simon , Chi Shihong , Rivas Jhon , Hallin Jim
Published: September 2014

The drilling and completion of wells in resource plays has tended to be based on drilling a pre-determined number of wells with uniformly spaced laterals drilled on pre-defined azimuths. The development of resource plays is now incorporating geophysics. Workflows have been developed that make 3D seismic data relevant to unconventional resource optimisation and to improve the economics of exploration and development. This can be achieved by constructing models, incorporating data sets derived from the seismic volumes and wireline data and then forward modelling and subsequently optimising well placement and hydraulic fracture design.

The workflow described here starts with a 3D surface-seismic multi-component data set and goes through to hydraulic fracture simulation and potential well optimization achieved through the construction of a discrete fracture network (DFN) model. The data sets are derived from azimuthal velocity analysis and anisotropic parameter calculations; seismic attribute analysis, interpretation and inversion provide a rich data source to develop a model, driven by deterministic data.

Three theoretical wells were included in the model, the location of one indicated that it was drilled into the intersection of two faults which could have been avoided. The other two were forward modelled, simulating hydraulic fracturing; this showed that in areas of high fracture density there was a larger number of stimulated fractures and predicted micro-seismicity, suggesting the reactivation of pre-existing fault and fractures. In areas with lower fracture densities, additional fractures were generated suggesting that hydraulic fracturing would result in the generation of new tensile fractures.

The modelling provided an enhanced understanding of the reservoir, providing greater insight than would be obtained from co-rendering. Importantly, the model tested different well positions, stage spacings and drilling azimuths. In this case study the locations and azimuths of the laterals were changed with differences in the stage-to-stage stimulated volume of between 3 and 30%. This was particularly the case for the central stages of the modelled wells and this has clear financial implications in the development of the resource in terms of drilling costs, completions and production.
Using High-Grading and Portfolio Tools to Allocate Resources among Shale Play Opportunities
Authors: Chorn Larry , Serice John , Del Rosario-Davis Suzanne
Published: September 2014

Portfolio theory requires the decision maker to associate a project's reward potential with its risk profile to characterize its contribution to an investment program. Reward and risk must be quantified in a manner that enables comparison across the set of investment alternatives to ensure that the capital allocation process is optimized. This quantification becomes difficult when the opportunity set contains very different investments, such as an offshore oil field, an oil sands project expansion, and a refinery upgrade. The risk components are different for each, and the rewards have different time horizons. Nevertheless, the risks and rewards for these types of investment opportunities are clear and can be modeled using historical information and experience.

Many companies have added shale plays to their investment portfolio, mixing one or more shale plays into an opportunity set. The risk and rewards of shale plays are gradually being understood. However, the ability to predict the economic performance in terms of production rate and reserve addition is not a science. Controllable and uncontrollable risks impact the expected reward. Controllable risks are quantifiable; however, uncontrollable risks, critical shale properties' distribution within the play and their effect on production, remain unpredictable before appraisal drilling.

Evaluating shale play investments as part of a portfolio requires quantifying both types of risk. Uncontrollable risks require new methods and insights to understand and quantify. Key shale property distribution prediction, coupling well logs with geostatistics, enables the quantification of uncontrollable risks in a shale play investment. The method quantifies relations between key shale properties and well performance to improve predrilling production forecasts. This paper addresses the method's application within and between shale plays to optimize capital allocations. This enables senior management to deliver production growth, cash flow, net present value (NPV), and reserve replacement, within capital constraints, from a portfolio comprising shale assets.
Advances in Understanding Liquid Flow in Gas Shales
Authors: Ghanbari Ebrahim , Xu Mingxiang , Dehghanpour Hassan , Bearinger Doug
Published: September 2014

Understanding water uptake of gas shales is critical for designing fracturing and treatment fluids. Previous imbibition experiments on unconfined gas shales have led to several key observations. The water uptake of dry shales is higher than their oil uptake. Furthermore, water imbibition results in sample expansion and microfracture induction. This study provides additional experimental data to understand the effects of rock fabric, complex pore network, and clay swelling on imbibition behavior.

We systematically measure the imbibition rates of fresh water, brine and oil into the confined and unconfined rock samples and crushed packs from different shale members of the Horn River Basin. We also measure the ion diffusion rate from shale into water during imbibition experiments. The results show that confining the shale samples decreases the water imbibition rate of samples tested parallel to the bedding. However, it has a negligible effect on water uptake of samples tested perpendicular to the bedding and on ion diffusion rates. The comparative study suggests that, for both confined and unconfined samples, water uptake is higher than oil uptake. The liquid imbibition and ion diffusion rates along the bedding are higher than those against the bedding. Surprisingly, the crushed samples show a completely different behavior. The oil uptake of crushed packs is higher than their water uptake. The data suggest that the connected pore network of the intact samples is water wet while the majority of rock including poorly connected pores is oil wet. This argument is backed by complete spreading of oil on fresh break surfaces of the rock.
Soil Water Dynamics and Evapotranspiration under Annual and Perennial Bioenergy Crops
Authors: Yimam Yohannes Tadesse , Ochsner Tyson E. , Kakani Vijaya Gopal , Warren Jason G.
Published: September 2014

Understanding soil water dynamics and evapotranspiration (ET) is imperative to predict the interactions between bioenergy cropping systems and water resources; yet measurements of these variables under bioenergy crops in the U.S. Southern Great Plains (SGP) are limited. The objectives of this study were to quantify and compare soil water dynamics and ET under switchgrass (Panicum virgatum L.), biomass sorghum [Sorghum bicolor (L.) Moench], and mixed perennial grasses managed for biofuel production. Soil water content was measured from 2011 through 2013 at Stillwater, OK, and from 2012 through 2013 at Chickasha, OK, and ET was estimated using the soil water balance approach. For these crops, soil water depletion occurred mainly above the 2.0‐m depth, suggesting negligible root water uptake below 2.0 m. Growing season soil water depletion ranged from 4 to 287 mm and was greater (α = 0.10) for sorghum than switchgrass in 2 out of 5 site‐yr, while mixed grasses exhibited the greatest soil water depletion in 1 out of 3 yr. Growing season soil water depletion was positively related to initial soil water content. Crop year ET ranged from 493 to 846 mm and was greater for switchgrass than sorghum in 2 out of 3 site‐yr. At Stillwater, average crop year ET measured for 2 yr was 676 mm for switchgrass, 630 mm for sorghum, and 717 mm for mixed grasses. In the SGP, rainfed bioenergy production systems based on biomass sorghum may consume less water per unit land area than systems based on perennial grasses.
Auditing and monitoring to enhance energy efficiency (AGBAR experience)
Authors: Imbernon J. A. , Aldea X. , Usquin B. , Marin D.
Published: September 2014

The changing global energy environment which promotes efficiency in energy use and production as well as the use of renewable energies has led to the need for appropriate methodologies and tools in order to manage energy more efficiently. The objective of this paper is to describe the methodology and tools developed and implemented by Aqualogy (a subsidiary company of the AGBAR water utility company, specialised in technology) in order to improve energetic performance and reduce carbon dioxide (CO2) emissions from water facilities. The methodology combines energy auditing with an energy consumption monitoring plan. Some tools have been developed in this field in order to support decision-making, such as those regarding tariff optimisation, and prediction of equipment anomalies that could lead to an increase in energy consumption. Using the tool CAFCA, a carbon footprint calculator specifically for the water cycle, it is possible to report greenhouse gases emissions and to quantify savings in CO2 emissions. By applying this methodology to 21.7% of AGBAR's facilities we have been able to observe a reduction of 3% audited energy, which means 6% of the facilities' energetic cost.
Water pipes: why ‘lifetime’ is not an adequate concept on which to base pipe renewal strategies
Authors: Renaud E. , Bremond B. , Le Gat Y.
Published: September 2014

Stakeholders involved in the renewal of drinking water pipes almost always use mean ‘lifetime’ values, which are set by an expert based on material type. A common approach to estimating replacement requirements is to assume that all pipes of the same class of material are renewed when they reach an age equal to their average ‘lifetime’. However, experience shows that for the same type of pipes, very different average ‘lifetime’ values are used, leading to inaccurate estimations of renewal requirements. Furthermore, the notion of ‘lifetime’ can lead to confusion between ‘financial requirements’ and ‘practical rehab requirements’. This study highlights the advantage of considering that pipes of the same class of material can have different lifetimes, the values of which can then be represented in a statistical ‘survival curve’. Replacement needs generated through this curve are then smoothed, allowing realistic annual renewal budgets to be calculated. Given the risk of incorrect evaluation that the term ‘lifetime’ may entail, the term should be avoided when discussing pipe renewal. It would appear preferable to use the term ‘service life’, which clearly expresses the choice to be made by decision makers between repair and renewal.
Public-Private Partnership approach towards enhancing water accessibility in Busia Municipality, Kenya
Authors: Kombo Paul Nakhungu , Kipkorir Emmanuel Chessum , Ekisa George Tom
Published: September 2014

Access to safe drinking water remains a challenge for most developing countries including Kenya, which is already classified as water-scarce. To enhance water supply to consumers, the Government of Kenya enacted the Water Act 2002 that opened the door for private sector to partner with the government to revitalize water service delivery. As a result, the government has partnered with the private sector and civil society organizations to enhance access to safe drinking water and sanitation services with a special focus on the materially-dispossessed households. However, the partnership is faced with challenges including inadequate resources and poor working relationship between the public and private sector. This paper assesses the impact of the partnership approach in scaling up water service provision in order to enhance its access by poor households. Household survey and key informants interviews were the main data collection methods and the collected data was analysed using descriptive statistics. The study found out that Public-Private Partnership (PPP) approach has enhanced water accessibility in Busia Municipality since the majority of households (84.4%) can access water within a distance less than one kilometre, however, the residents' complaint of high water bills attributed to the private sector involvement.
Case study: Use of flotation for industrial stormwater treatment
Authors: Ksenofontov Boris S. , Ivanov Mikhail V.
Published: September 2014

This article presents a novel approach in industrial stormwater treatment based on flotation. For this use, the technique has some significant enhancements, including the addition of a sorption filter in the flotation tank. The approach was implemented at the Ust'-Ilimskaya hydropower plant. This type of stormwater treatment plant may be used when the strictest stormwater drainage rules are applied.
Constructed wetlands for the treatment of raw wastewater: the French experience
Authors: Troesch S. , Salma F. , Esser D.
Published: September 2014

Vertical flow constructed wetlands for small communities (<5,000 population equivalent) have been successfully developed in France since the 1990s (currently about 3'000 plants are in operation). This paper summarizes the results and efficiencies of 70 plants designed and built by Epur Nature or SINT. The results show clearly that the design performs well for organic matter removal and nitrification and makes sludge management easy. Therefore if well designed, such systems can achieve an outlet quality of BOD5 < 20 mg/L, chemical oxygen demand <90 mg/L, suspended solids <30 mg/L and TKN < 15 mg/L. In addition, some new configurations involving a French vertical first stage fed with raw sewage, patented by Epur Nature, are presented as an aid to reduce the global footprint.
The Design of Oil Well Downhole Mechanical Analysis System
Authors: Zhao Panpan , Wang Xiufang , Liu Ying , Wu Mengmeng
Published: September 2014

With the rapid development of drilling technology, borehole has become increasingly complex demanding
higher standards for downhole operation. The downhole mechanical analysis is an important part of the oil well
production analysis. It is very important for the process of drilling, completion and work over operations. The previous
operation based on experience has been unable to meet the modern production requirement in accuracy. For the present
situation of oil field information construction and the problems being confronted in the production process, this paper
designs and implements the downhole mechanical analysis system based on .NET. This system can provide quick and
accurate analysis results of downhole string in the process of well production and can also provide the basis for equipment
selection and scheme selection in the production process.

The design of this system mainly includes two parts: part one consists of the analysis of the deformation to the tubular
column with the packer and the other part comprises of the analysis of frictional resistance of tubular column. This system
has the advantages of simple operation, accurate calculation, clear analytical results and comprehensive analysis.
Parameter Influences of Light Floating Slab on Its Vertical Vibration
Excited by Track Irregularity
Authors: Shi Guangtian , Yang Jianjin , Yang Xinwen
Published: September 2014

According to the structure characteristics of railway viaduct with light floating slabs, a frequency domain
dynamic model of the vehicle-light floating slab track-viaduct bridge vertical coupling system is established. The Green
functions are used to quickly calculate the receptance response of the system, and then the pseudo excitation method is
used to further analyze the parameter influences of the floating slab on the vertical vibration excited by the track
irregularity. The parameters of the floating slab have obvious effects on its vertical vibration, so as we strive to reduce the
vibration and noise radiation of the railway by changing the parameters of the floating slab, the disadvantages to the
vibration and noise control of the floating slab have to be taken into consideration.
Random Response of Rotor System on the Filtered Gaussian White Noise
Earthquake Ground Acceleration
Authors: Zheng-Hao Wang , Xing-Rong Xiong , Qing-Xin Meng , Xing-Tao Yang , Qing-Tai Xi
Published: September 2014

With the pseudo-excitation method, the random response of a cantilever double-disc rotor system under the
filtered Gaussian white noise earthquake ground accelerated random excitations, is analyzed by computer numerical
simulation. The results show that the random response is relatively strong during an earthquake of the horizontal direction
while the cantilever disk vibration is the strongest. The inherent frequency of the site soil has a great effect on the
random response in the horizontal direction, while the system frequency characteristics have a great effect on the random
response in the vertical direction. The rotor imbalance random excitation intensity does not change the peak frequency of
the response spectrum. However, the system random vibration response is large when the excitation intensity is in a high
level state. It has a great impact on the low and high frequency of non-cantilever disc, the low frequency of the cantilever
disc, the high-frequency of non-cantilever bearing vertical vibration and the high-frequency of cantilever bearing the
intensity around the high-frequency random response.
Study on Tractor Semi-Trailer Roll Stability Control
Authors: Zhou Shuwen , Zhang Siqi
Published: September 2014

The rollover accidents in the tractor semi-trailer are often fatal and many factors could cause the tractor semi-trailer
rollover. In this paper, a rollover prevention control method was proposed based on real-time calculation of rollover
index. The vehicle Center of Gravity (CG) height from the ground is an important parameter in the rollover index and it is
estimated through lateral acceleration sensor and suspension deflection sensors. Comparing the rollover index with the
preset threshold, the differential braking will be applied to corresponding wheels once the trigger conditions are met. A
roll stability control simulation was performed on the dynamic model based on virtual prototyping. The results show that
the rollover prevention control proposed in this paper can stabilize the tractor semi-trailer and prevent from rollover on
high speed curve driving.
Experimental Analyses of Mechanical Performance of CFST Column to Assembled Steel H-Beam Connections
Authors: Chunyi Cui , Jinfeng Zhao , Yannian Zhang , Wenxin Zuo
Published: September 2014

The mechanical performance of a new proposed type of cross-shaped connection with concrete-filled steel
tubular (CFST) column and assembled steel H-beam was investigated. Cyclic loading tests on the cross-shaped
connections are carried out by using MTS servo loading system. Comparative analyses are conducted based on the
experimental results including hysteretic curves, skeleton curves and stiffness degradation curves as well as ductility
coefficients of cyclic loading tests. Furthermore, effects of geometric parameters of ring-stiffened plate, axial compression
ratio and backing plate on the deformation performance of cross-shaped connections are analyzed. The results show that
the increase of width of ring plate and the shape change of ring plate from square to circle can both significantly improve
the ductility and the hysteretic characteristics of connection. It is emphasized that the specimen with square ring plates is
of better deformation performance but lower bearing capacity than the ones with circular ring plates. Besides, the backing
plates always have positive effects on the hysteretic characteristics, ductility and energy dissipation of the CFST column
connections. Conversely, the increase of axial compression ratio contributes negatively to both the bearing capacity and
deformation performance of the connection specimens. It can be concluded that the presented cross-shaped connection is
of good deformation performance relating to hysteretic characteristics, energy dissipation and ductility, which can provide
reference towards engineering practice with potential perspective application.
Laminated Structures and Measurement of Magnetostriction for Transducer Applications
Authors: Cao Qinghua , CaoChen Dingfang , Lu Quanguo , LuYan Jianwu , Tang Gang , Zhu Zhifang , Xiaoxing Zhang , Zhen Tao
Published: September 2014

This paper aims to designed a prototype for achieving the full magnetostriction of Galfenol, Lamination
struction of transducer is designed and the radiation impedance is expressed in mechanical terms, a simplified onedimensional
modeling of SPICE magnetostrictive transducer is established, the electrical input impedance is simulated as
the function of frequency and experimentally adjusting the values is to match an existing impedance curve. a good fit
between model and measurement is shown by measured and simulated electrical input impedances for the device.
The Stick-Slip Vibration and Bifurcation of a Vibro-Impact System with
Dry Friction
Authors: Gao Quanfu , Cao Xingxiao
Published: September 2014

In this paper, the periodic motion, bifurcation and chatter of two-degree-of-freedom vibratory system with dry
friction and clearance were studied. Slip-stick motion and the impact of system motions were analyzed and numerical
simulations were also carried out. The results showed that the system possesses rich dynamics characterized by periodic
motion, stick-slip-impact motion, quasi-periodic motion and chaotic attractors, and the routs from periodic motions to
chaos observed via Hof bifurcation or period-doubling bifurcation. Furthermore, it was found that there exists the chatter
phenomena induced by dry friction in low frequency, and the windows of chaotic motion are broadened in the area of
higher excitation frequencies as the dry friction increases.
Study of Load Bearing Capacity of Profiled Steel Sheet Wall Subjected
to Combined Bending and Vertical Compression in Electrostatic
Precipitator
Authors: Wang Dengfeng , Yu Yongfu , Pan Licheng , Dai Haijin
Published: September 2014

For some electrostatic precipitators, profiled steel sheets are used as casing wall which is subjected to both
bending and vertical compression. By nonlinear finite element method, the influences of structural parameters on load
bearing capacity of profiled steel sheet wall were investigated. For the loading path, the uniform transversal pressure was
applied firstly, and then the vertical compression was applied until the wall failed. The results indicate that the vertical
compression resistance of profiled sheet decreases with the transversal load or the increasing sheet span. For certain sheet
shape, the vertical compression resistance of profiled sheet decreases with the wall width increasing. The vertical
resistance of the profiled sheet whose tensioned flanges are connected with the side columns is more than that whose
compressed flanges are connected with the side columns. When the vertical compression resistance is calculated
according to the buckling evaluation method of cold-form thin-walled steel member, the value is usually less than the
solution from finite element method. Consequently, the load bearing capacity based on the related method of cold-form
thin-walled steel member can be taken as a reference solution for the profiled steel sheet subjected to combined bending
and vertical compression.
Weight-Loss Therapy in Type 2 Diabetes: Effects of Phentermine and Topiramate Extended Release
Authors: Garvey W. Timothy , Ryan Donna H. , Bohannon Nancy J.V. , Kushner Robert F. , Rueger Miriam , Dvorak Roman V. , Troupin Barbara
Published: September 2014

OBJECTIVE

Treatment algorithms for type 2 diabetes recommend weight loss for disease management. The safety and efficacy of treatment with phentermine (PHEN)/topiramate (TPM) extended release (ER) plus lifestyle modification for weight loss and glycemic benefits were assessed in two randomized, double-blind, placebo-controlled 56-week studies of obese/overweight adults with type 2 diabetes.

RESEARCH DESIGN AND METHODS

The OB-202/DM-230 Study was a 56-week phase 2 trial that randomized subjects to receive once-daily placebo or PHEN/TPM ER 15 mg/92 mg (15/92). The primary end point was change in HbA1c level. A post hoc analysis of a subpopulation with type 2 diabetes from a second study, CONQUER, is also presented. All subjects made lifestyle modifications, and comorbidities were managed to the standard of care.

RESULTS

The study groups comprised 130 subjects with type 2 diabetes enrolled in the OB-202/DM-230 Study (mean baseline HbA1c 8.7% [72 mmol/mol]) and 388 subjects with type 2 diabetes in the CONQUER Study (mean baseline HbA1c 6.8% [51 mmol/mol]). At week 56 in the OB-202/DM-230, change in weight (from intent-to-treat sample with last observation carried forward [ITT-LOCF]) was −2.7% for placebo and −9.4% for PHEN/TPM ER 15/92 (P < 0.0001 vs. placebo). Change in HbA1c level (from ITT-LOCF) was −1.2% (−13.1 mmol/mol) for placebo and −1.6% (−17.5 mmol/mol) for PHEN/TPM ER 15/92 (P = 0.0381). In both the OB-202/DM-230 and CONQUER, greater numbers of patients randomized to receive PHEN/TPM ER treatment achieved HbA1c targets with reduced need for diabetic medications when compared with the placebo group. Common adverse events included paraesthesia, constipation, and insomnia.

CONCLUSIONS

PHEN/TPM ER plus lifestyle modification can effectively promote weight loss and improve glycemic control as a treatment approach in obese/overweight patients with type 2 diabetes.