bluuebunny/crossref_metadata_2025 huggingface dataset:
The European Union – From Agenda Setting and Media Frames to Citizens’ Conversations
Authors: Corbu Nicoleta , Ștefăniță Oana , Oprea Denisa , Udrea Georgiana
Published: March 2016

Agenda setting and framing have been shown to affect public opinion on a variety of topics through accessibility and interpretation schemas. Since most of the citizens lack a direct experience in European matters, media might be a key dimension in determining how citizens approach issues related to the European Union. Therefore, this study examines the effects of agenda setting and framing of European subjects on citizens’ interest and interpersonal conversations agenda. The research is based on a comparative analysis between two corpus of articles published between 1-31 March, 2013 and 25 April-25 May, 2014 on the two main online news portals in Romania (ziare.com and hotnews.ro), and 39 in-depth interviews. The findings show that citizens rely on national media for information about the EU; thus, through agenda setting and framing effects, media provide a solid base for debate as well as interpersonal discussion parameters. However, citizens’ concern about EU topics is relatively low and their involvement is driven by a national or personal relevance of the topic.
German Quality in the Service of a European Public Sphere? An Analysis of the Deutsche Welle’s European Journal program
Authors: Popescu Oana Ludmila
Published: March 2016

The economic crisis of the European Union has rendered the European public sphere as a forever emerging concept marked by uncertainties regarding its structure. In this context, eyes of both European officials and citizens turn towards the media, the main communication link between the EU and its citizens. The present paper looks at a media product that is designed to permeate multiple national public spheres, the weekly news show European Journal, a half-hour TV program produced by Deutsche Welle and rebroadcast by partner TV channels throughout Europe. Considering the main characteristics of the European public sphere as identified in the literature, with a focus on horizontal Europeanization, and using the method of content analysis, this paper looks at the means employed by the European Journal to support the integration process and to add a European dimension to national public sphere. Findings suggest that the type of public sphere promoted by the European Journal is not centered around the EU as a distinct entity, but around the member states, approach which supports the idea of a horizontal Europeanization.
The discursive construction of Romanian immigration in the British media: Digitized press vs. Television documentaries
Authors: Cheregi Bianca Florentina
Published: March 2016

This paper looks at how the media – particularly the British press and television – frames the issue of Romanian immigrants in Great Britain, in the context of the freedom of movement for workers in the European Union. The study focuses on the frames employed by the British journalists in constructing anti-immigration discourses in the digital and the TV sphere, comparatively. This study analyzes the stereotypes about Romanian people used in two British media formats and the way in which they affect Romania’s country image overseas. Using a mixed research approach, combining framing analysis (Entman, 1993) with critical discourse analysis (Van Dijk, 1993), and dispositif analysis (Charaudeau, 2005) this article investigates 271 news items from three of the most read newspapers in the UK (The Guardian, Daily Mail and The Independent), published online during January 2013 – March 2014. Also, the paper analyzes three film documentaries from BBC (Panorama – The Romanians are Coming? – BBC1, The Truth About Immigration – BBC2 and The Great Big Romanian invasion – BBC World News). The analysis shows that the British press and television use both similar and different frames to coverage Romanian migrants. The media also infer the polarization between “Us” (the British media) and “Them” (the Romanian citizens).
Twenty-nine-Year Follow-up of Nonoperatively Treated Three-Level Lumbar Spondylolysis
Authors: Wu Xiao-Dong , Wang Xin-Wei , Chen Hua-Jiang , Cao Peng , Chen Yu , Raley Thomas John , Chen Yuan-Yuan , Yuan Wen
Published: March 2016

Update

This article was updated on May 25, 2016, because of a previous error. On page 4, in the address block, one of the e-mail addresses was incorrectly identified. The line had previously read “E-mail address for Y.-Y. Chen: yugangg@163.com.” The sentence now reads “E-mail address for Y. Chen: yugangg@163.com.”

Case:

Multilevel spondylolysis, especially involving more than two levels, is rarely encountered in clinical practice. We present a case of three-level spondylolysis with two-level spondylolisthesis followed for twenty-nine years after nonoperative treatment. The patient was a forty-six-year-old man who presented with stabbing pain in the lower left portion of his back without radiating symptoms or neurological deficit. Lumbar radiographs showed bilateral pars defects at L3, L4, and L5 and grade-I spondylolisthesis at L4/L5 and L5/S1, but flexion and extension views showed no obvious translation. Review of medical records showed that the patient had already had three-level bilateral spondylolysis at L3, L4, and L5 almost thirty years ago. The patient had no history of lumbar surgery during the intervening years. Nonsteroidal anti-inflammatory drugs were initially prescribed. Physical therapy was prescribed for eight weeks, and the low back pain improved.

Conclusion:

For patients with multilevel lumbar spondylolysis without neurological symptoms and with slippage of <25%, we recommend conservative treatment with regular follow-up.
Drilling Training Requirements to Meet the Challenges of the Nineties
Authors: Fraser Ken
Published: March 2016

This paper looks at Drilling Training as it is applied at present and how it may-have to be changed to prepare it for the "Nineties".

In any job position a clear set of attributes are needed for staff to perform efficently. These can be broken down as follows:

Defined Education Defined Skills and Capabilities Defined Experience Defined Attitude

Training fulfills the role of ensuring that staff have these skills.

In the Nineties the Drilling Industry will change. Some of the new Technologies which are now appearing will become common place. These Tectinologies will probably include some or all of the following:

An Audited approach to Training Effectiveness Reduced Manning Levels/faulti Skilled Personnel Automated Rigs/Mechanical Pipe Handling Systems Tender Assisted Drilling Subsea Production Systems Electric Submersible Pumps Utilisation New Secondary and Tetiary Recovery Systems Horizontal Drilling Technology

These are comparatively new skills which must be mastered. All of the basic Drilling Skills which have been required to date are also needed. The time available to achieve all of this will probably be reduced by Operational Expansion following a period of Industrial recession.
The Ocean Odyssey: Well Control Project
Authors: Wann Kevin E.
Published: March 2016

The Ocean Odyssey well control project showed that it was possible to carry out a surface well kill operation by using the combined capabilities of a floating drilling rig moored at a location remote from the out of control subsea well with dynamically positioned diving support/well services, construction vessies. Novel techniques were used to abandon the well including the industries first subsea perforating job from a dynamically positioned monohull well servicing vessel.
Optimised Design, Operations Procedures and Materials Improve Cementing Results in the North Sea
Authors: Boyington W. H. , Drawe M. S. , Sweatman R. E. , Gill S. C.
Published: March 2016

The requirements for zonal isolation in Conoco's Hutton field have greatly increased as production from the field continues. High differential pressures approaching 1500 psi between zones which are less than 15' apart have made obtaining effective isolation of paramount importance. Problems with zonal communication behind the production casing were experienced due to an incomplete cement sheath. High pressure water zones flowed through cement channels to a low pressured oil zone and reduced oil production. In addition, water injection did not enter the desired zone.

A review of the methods used for primary cementing was completed and recommendations were made to improve the quality of the cement job. These recommendations were then implemented on subsequent wells. These recommendations included practices for conditioning the hole for the casing, designing the cement slurry and spacer system, and running and cementing the casing.

A high priority was placed on preparation of the hole for casing. Drilling practices were addressed such as maximum preferred hole angle, circulation rates, properties of the drilling fluid and making a conditioning trip after logging.

The cement slurry design was addressed in concert with the mud and spacer systems. A new test was devised to design a spacer system suitable for water wetting and mud filter cake removal. Rheological, settling and thickening properties of the slurry were addressed.

Casing running and cementing practices were reviewed. Sandblasting the casing, casing centralisation, casing running speeds and slurry volumes were, engineered. Fluid properties and circulation rates were optimised prior to cementing, as well as the use of multiple wiper plugs for separation of the mud, spacers and cement. Selection of cement mixing equipment and onsite supervision were also addressed.

As a result of this work, substantial improvements in primary cementing have resulted in near perfect cement bonds and elimination of zonal communication in the Hutton field.
On the Value of Information
Authors: Gerhardt J. H. , Haldorsen H. H.
Published: March 2016

Often it has to be decided if additional information should be collected or if further studies are necessary before a new field development or an incremental development project can be initiated. Ideally, additional information should be gathered only as long as it contributes to improving the total project net present value and reduces the company's Investment risk.

However, it is usually very difficult to attach an economic value to a specific data gathering activity. Lohrenz (1) presented a method for evaluating the value of information. This approach has been utilized in connection with decision making on: 1) a long term test of a vertical well in a small North Sea oil field, 2) a North Sea polymer pilot project, 3) extended production testing of a horizontal well in a reservoir with a thin oil rim. The method, its application and results for the three cases are described in this paper, advantages and disadvantages of the method are also discussed.
Hydraulic Fracturing Fluids: The Crosslinking of Hydroxypropyl Guar With Titanium Chelates
Authors: Clark P. E. , Barkat O.
Published: March 2016

The rheological behavior of crosslinked hydroxypropyl guar systems is important in both the engineering design of fracturing treatments and the laboratory evaluation of potential fracturing fluid systems. A great deal of information is available in the literature from a number of workers, but there is still much to be learned about the nature of these systems.

Results obtained in this study provide insight into the effects of shear history, residence time, and chemical composition on the crosslinking reaction. Experiments are conducted in both tube and slot flow rheometers and a Rheometrics Pressure Rheometer (concentric cylinder geometry). Mixing of the crosslinker and hydroxypropyl guar solution is accomplished with a special mixing head which provides for continuous mixing. Using this mixing device, measurements are made on fluids which have not experienced any dead time (luring the mixing and measurement process.

Both steady and dynamic (oscillatory) shear tests are presented. The steady shear data provides insight into the nature of the reaction in laminar flow. An abrupt change in the reaction mechanism appears to occur below 100 s-h The fluid which exists in the slot or pipe in steady shear tests changes from a viscous fluid to a gel. Dynamic tests yield information on the effects of shear on the gel structure. Long term shear at elevated rates appear to irreversibly damage the systems ability to crosslink. The fluids which result from these tests either fail to crosslink or they do not form the same network structure present in systems which have not been subjected to high shear.

The results of a fracturing treatment are influenced by fluid performance. A better understanding of the rheology and the crosslinking process in commonly used fracturing fluids will improve our ability to optimize fracturing treatments.
Development of Low-Permeability Gas Reserves Hydraulic Fracture in the Surat Basin, Australia
Authors: Porteous W. R. , Delbaere M. A.
Published: March 2016

Hydraulic Fracturing of the Rewan and Showgrounds formations in the Namarah-Parknook fields of the Red Cap Block was performed in an attempt to establish commercial rates of gas production from a large volume of potential gas reserves in the Surat Basin. These formations had not been previously-fractured in Australia.

A geological and engineering study was made of the subject area before proceeding with the fracture treatments. This quantified the available gas-in-place and allowed selection of the best candidate wells for stimulation. Several cores were available from wells in the area and selected lengths were sent to the service company stimulation laboratory in the U.S.A. for detailed analysis to determine the best parametric values to employ in the computer-assisted design of the proposed fracturing treatments.

Four stimulation treatments were carried out on three wells in the area, with varying results. Similar sized fracture treatments were performed, but many changes were made to the pre-frac completions as well as the treatments themselves as they progressed. The changes were made to optimize designs, based on experience gained, and reduce costs while still achieving well-contained deep fractures in the pay zones. The first treated well, Namarah No. 2 was extensively production tested before stimulation, to allow an accurate comparison with post-frac production rates.

Selection of the proppant was based on the crushing forces on the proppant as well as on the ultimate reservoir pressure at depletion of the formations proposed for fracturing. Pumping rates were determined by the thickness of the pay zone to be fractured and the estimated degree of containment which could be expected from the natural barriers to fracture propagation contained in surrounding formations. Size of the treatment was based on the natural permeability-thickness of the reservoir rock and drainage area, as well as the need to achieve commercial gas flow rates from successful wells. Extensive use of computerized on-site monitoring technology and equipment was employed.
Modelling Gas Deliverability from a Group of Fields that Communicate Via an Aquifer
Authors: Tucker C. C.
Published: March 2016

Several hydrocarbon reservoirs in the Triassic Showground Formation of Queensland's Bowen Basin share an aquifer of moderate strength. Field discovery pressures have indicated depletion levels of up to 330 psi [2.28 MPa] due to communication via the aquifer with neighbouring fields. Reliable estimates of original gas in place (OGIP) are not attainable by conventional material balance techniques. Modelling the fields as interconnected tanks, linked to a two stage aquifer system, enabled ten years of historical performance to be matched. The derived OGIP's and aquifer size/strength are consistent with the current geologic model.

A production forecasting model was developed which integrates the reservoir/aquifer system with well inflow, tubing pressure drop and surface facility constraints. The timing of wells watering out is critical to deliverability predictions and development planning. The model tracks the gas-water contact by performing reservoir sweep efficiency calculations according to depth versus volume curves. Wells are scheduled according to liquids yield priority to meet sales gas demand.

Various sales gas market alternatives have been successfully evaluated by the model. The modelling of the interconnected reservoir/aquifer system allowed the sensitivity to field withdrawal rates to be addressed. This capability was essential in establishing the optimal timing for field compression. Future plans for development wells and the timing of new field tie-ins have also resulted from model predictions.
Model for Predicting Wellbore Pressures in Cement Columns
Authors: Chenevert M. E. , Jin Liang
Published: March 2016

A model for calculating the time dependent wellbore pressure response of a hole filled with cement is presented. Variables include the time dependant characteristics of chemical shrinkage, filtration, and rheological properties.

Cement properties of chemical shrinkage and gelation were experimentally determined and used in model calculations.

Calculated results for neat cement agree quite well with field data. Model results also show that more rapid declines in wellbore pressures exist for cements with higher chemical shrinkage, filtration, or gelation.

Equations are derived and analytical techniques presented for the development and application of the model.

Also presented are model results for two cements which show that large differences in wellbore pressures can be obtained from cements with varying characteristics.
An Analysis of Predicted Wellbore Trajectory Using a Three-Dimensional Model of a Bottomhole Assembly With Bent Sub, Bent Housing, and Eccentric Contact Capabilities
Authors: Williams J. B. , Apostal M. C. , Haduch G. A.
Published: March 2016

Bent subs and bent housing motors are one of the most important class of tools available to aid drilling engineers in deviation and directional control of wellbores. Even though such tools may spend very little actual time drilling a hole, the quality of their performance often determines the difference between success or failure of a well as far as execution of the trajectory plan (or design) of the well is concerned.

Despite the importance of bent subs and bent housing motors to the drilling community, the previous lack of available rigorous analytical models has assured that the design and selection of these tools remain confined to the realm of experience.

Recently, however, a sophisticated numerical algorithm has been developed by the authors which implements the Finite Element Method in modeling the nonlinear behavior of steerable bottomhole assemblies containing motors with multiple bends, bent subs, bent housing motors, steering tools, eccentric contact stabilizers, and wear pads (kick pads).

First, this paper provides a brief description of the steerable bottomhole assembly analysis software model. Second, this paper presents a variety of applications of the model in field drilling situations to demonstrate the model's ability to (i) accurately predict the actual response in these field cases, and to (ii) permit a drilling engineer to isolate the pertinent downhole structural mechanism operable during a given wellbore trajectory deflection scenario.
Gas Kick Experiments in Oil-Based Drilling Muds in a Full-Scale, Inclined Research Well
Authors: Rommetveit R. , Olsen T. L.
Published: March 2016

Gas kicks in oil-based muds have been studied with experiments in an inclined research well.

A total of 24 different gas kick experiments were performed, and various parameters were varied. The instrumentation and data acquisition systems were complex, and nine surface and 10 downhole parameters were logged simultaneously.

The data presented reveal the dynamic development of kicks in OBM, helps understanding the kick process and give important implications for kick detection and well control. The data are analysed with relation to physical processes and drilling operations.
New Gas Logging System Improves Gas Shows Analysis and Interpretation
Authors: de Pazzis L. L. , Delahaye T. R. , Besson L. J. , Lombez J. P.
Published: March 2016

A new gas logging system has been developed, field-tested and is now fully integrated in mud-logging units. In this system, the volume of mud put through degassing per time unit is a constant, whatever the actual drilling mud flowrate may be. Also, the greater amount of energy spent at the degasser increases extraction efficiency. Moreover, mud samples can be taken close to the bell nipple, without modifying the rig equipment, thus reducing surface gas losses. The gas show analysis is done through a double Flame Ionization Detector (FID) system, faster than most conventional systems. The sensitivity, even at low detection level, is remarkable.

Field tests have been performed in the Paris Basin, where the GOR of the oil produced is very low. When conventional gas analysis devices do not detect anything, the new gas logging system enables a clear reservoir identification with good correlations with wireline logs. Another main feature of the system, also demonstrated by field tests performed in the North sea, is its ability to determine the compositional ratios of the light end components of reservoir fluids. This was verified by correlations with analyses of the associated gas produced with oil.

The quality of the measurements performed by the new gas logging system will probably reinforce the reliability of mud-logging formation evaluation techniques.
Formation Evaluation While Drilling With a Dual Propagation Resistivity Tool
Authors: Fredericks P. D. , Hearn F. P. , Wisler M. M.
Published: March 2016

The Dual Propagation Resistivity (DPR*) tool provides two electromagnetic propagation resistivity measurements to improve formation evaluation in all types of muds. It transmits a 2 MHz signal into the formation and measures the phase difference and amplitude ratio between two closely spaced antennas. These measurements are converted into phase difference resistivity, Rpd, and amplitude ratio resistivity, Rar, and together with gamma ray they are transmitted to the surface for real-time decision making. They are also stored in downhole memory and can be sampled as fast as every 5 seconds producing a high density data log for petrophysical analysis. The sample rate can be adjusted on the rig for changes in the drilling rate of penetration.

The depth of investigation of Rar is deeper than Rpd but both are deep enough to eliminate most borehole effects. Beds as thin as the antenna spacing can be detected and the vertical resolutions are such that no corrections are needed in beds too thin for conventional induction tools. Two curves allow the effects of invasion and hydrocarbon to be distinguished, and log quality to be better controlled.

Log behavior is similar to a dual induction log in most lithologies but there are important differences. Normally, the DPR logs are made just after drilling when invasion is not deep enough to affect either Rar or Rpd. In this case they both will read true formation resistivity, Rt. In a hydrocarbon sand Rpd and Rar will both read high, though Rar will be less accurate than Rpd if Rt is over 20 ohm-meters. Ideally, Rpd and Rar should read the same in impermeable lithologies, regardless of resistivity. In high resistivity formations Rpd is more accurate than Rar and it is less affected by the dielectric constant of the formation.

Log quality is monitored in real-time by evaluating the separation of the two resistivities as a function of the lithology. In an impermeable, low resistivity formation the curves will read the same. If they do not, and the lithology does not change, then damage to one, or both, of the antennas is indicated. The DPR tool is calibrated for temperature and the antennas are hardened against the effects of hydrostatic pressure.
Calculation of MWD Electromagnetic Resistivity Tool Response by a Finite-Element Method
Authors: Brooks A. G. , Hall H. E.
Published: March 2016

A Finite Element Method (FEM) model of an electromagnetic resistivity tool has been developed. Verification of the model indicates agreement with both analytical and experimental methods, while noting the differences between the two approaches. FEM results for a new electromagnetic resistivity tool include correction charts as well as data on field distributions, pseudo-geometric factors, and bed response in the presence of a borehole (which can be difficult to obtain by other methods). Appendices present the theory of the analytical and FEM approaches.
Cyclic Steam Pilot in Gravity Drainage Reservoir
Authors: Chiou R. C. S. , Murer T. S.
Published: March 2016

This paper describes the performance of a cyclic steam pilot project in a steeply dipping (40 degrees) heavy oil reservoir in the Sho-Vel-Tum Field in southern Oklahoma. Steam injection was initiated in 1986 and there have been nine cyclic steam stimulations on four new wells to date.

The cyclic steam response shows a significant increase in oil production, as expected, relative to pre-stimulation production. The cyclic steam operation is quite unique because of its extremely high injection pressure (up to 1900 psi at the surface). In addition, incremental production from existing offset wells shows evidence of interwell communication of injected steam. Optimization of difficult field operating controls has a major impact on the cyclic steam performance in this reservoir. Techniques developed from the pilot experience may be extended to other areas where production is limited by problems inherent with high injection pressure, high downhole temperature, and excessive sand entry. Use of analytical and numerical models has provided insight in the salient aspect of cyclic steaming and aids in the evaluation of pilot performance.
Molecular Diffusion in Naturally Fractured Reservoirs: A Decisive Recovery Mechanism
Authors: da Silva F. V. , Belery P.
Published: March 2016

The purpose of this paper is to demonstrate the importance of the Fick's molecular diffusion in fractured reservoirs and to present a numerical solution to predict the related mass transfer.

As opposed to porous media where molecular diffusion is generally small, in naturally fractured reservoirs, molecular diffusion may be very important, as the dispersive flux through fractures rapidly increases the contact area for diffusion. Fick's molecular diffusion potential may even override viscous forces when hydrocarbon or inert gases are injected and the fracture spacing is small.

The importance of Fick's diffusion is largely illustrated in the present paper showing results from analytical models applied to field cases.

A method to predict molecular diffusion is presented and has been implemented in a very recent dual porosity, fully implicit, fully compositional, EOS based reservoir simulator. One advantage of the proposed algorithm, which is an extension of the Sigmund correlation, when compared to others, is that it requires only the component critical properties and other parameters used in any equation of state.

Results from the above referred reservoir simulator are also presented to illustrate the effect of molecular diffusion while injecting separator gas or inert gas in a North Sea volatile oil reservoir.

Solutions for molecular diffusion of gas in fractured undersaturated oil reservoirs, using single porosity simulators, are also described in the paper.
Displacements, Saturations, and Porosity Profiles from Steady-State Permeability Measurements
Authors: Potter G. F. , Groves D. R.
Published: March 2016

Steady-state permeameters were extensively automated to decide when steady-state conditions are reached and when to change the fluid injection ratios for reduced operator demand and improve data quality. A communication system was installed to allow monitoring and control of the permeameter using computers at remote locations. The permeameters use a X-ray scanning system to determine the fluid saturations. Since data are collected at incremental points along the length of the test rock, the saturation measurement system was used to determine the shapes of displacement fronts. Examples are given of immiscible gas-brine and oil-brine displacement fronts. A method for determining porosity profiles from steady-state data is given. Several examples of porosity profiles for sandstone and carbonates are presented.
Foam Performance Under Reservoir Conditions
Authors: Suffridge F. E. , Raterman K. T. , Russell G. C.
Published: March 2016

Foams that effectively reduce gas permeability were formed over a wide range of experimental conditions. The ability of selected foaming agents to form foam was evaluated in bulk foam measurements, screening core tests, and in reservoir condition core tests. Results reported show that oil usually adversely affected foam performance with higher molecular weight alkanes showing less of an adverse effect for the foaming agents tested. Foam can be effectively generated in an oil-wet porous medium but was shown to be much less effective than in a water-wet medium for the foaming agents studied. High pressure gradients of up to 4524 kPa/m (200 psi/ft) resulted in effective foam generation with an effective foam continuing to 8500 pore volumes of injected nitrogen. The enriched gas mixture used in this study was shown to adversely affect foam even though the foaming agent was selected through screening testing. This showed the importance of including reservoir condition testing prior to the final selection of a foaming agent for a given reservoir application. Effective foaming agents were identified for use in pilot tests in a typical West Texas CO2 flood and in a typical Canadian hydrocarbon miscible flood.
Tension Leg Platform Grout Logging
Authors: Carroll J. F. , Dupin R. M. , Leslie H. D. , Seligman K. , Briaud J. L.
Published: March 2016

Although the deepest conventional platform in the Gulf of Mexico is in 1760 ft of water, platforms are being designed for 3000 ft of water, wells have been drilled in 7500 ft of water, and leases have been purchased in 8500 ft of water.

The foundation systems for shallow-water platforms are predominately driven steel pipe piles. These piles are driven with underwater hammers when the water depth becomes deep. As water depth increases, the hammers become more expensive and less efficient. Technology already exists to drill holes in very deep waters, and the idea of using drilled and grouted piles for deep-water platforms has become very attractive.

Construction for a typical pile consists of drilling a large hole to about 350 ft, lowering a large-diameter steel pipe (24 in. or larger) to the bottom, and pumping grout from the bottom of the pile through a one-way valve into the pipe-hole annulus. This procedure is repeated in stages.

The use of drilled and grouted piles appears advantageous but it also poses some new problems. During the driving of a pile, measurements can be made from which an axial capacity can be inferred. This is not possible with a drilled and grouted pile. Attention must be focused on the quality of the grout job in order to ensure good bonding between the steel pile and the soil.

Integrity of the grout curtain and capacity of drilled and grouted piles were the two major topics of a research project. The integrity aspect was studied by installing a drilled and grouted pile with intentional defects and testing various oilwell logging tools to determine if they could detect the defects and be used as control during the stages of the grout process. To determine the capacity, drilled and grouted piles were installed and tension load tests to failure were performed on those piles. The integrity testing is reported in this paper.
Measurement of thermal emission during cutting of materials using abrasive water jet
Authors: Perzel Vincent , Flimel Marián , Krolczyk Jolanta , Sedmak Aleksandar , Ruggiero Alessandro , Kozak Drazan , Stoic Antun , Krolczyk Grzegorz , Hloch Sergej
Published: March 2016

This article deals with measurement of the thermal gradient on material during abrasive water jet cutting. The temperature was measured by thermocamera before the technological process started, during the abrasive water jet cutting process technology, and just after the cutting process. We performed measurements on several types of materials. We calculated the approximate amount of energy during the abrasive water jet cutting process technology that changes into thermoenergy, which is the current water pressure drained in a catcher tank.
Thermal analysis of physical and chemical changes occuring during regeneration of activated carbon
Authors: Radic Dejan , Stanojevic Miroslav , Obradovic Marko , Jovovic Aleksandar
Published: March 2016

High-temperature thermal process is a commercial way of regeneration of spent granular activated carbon. The paper presents results of thermal analysis conducted in order to examine high-temperature regeneration of spent activated carbon, produced from coconut shells, previously used in drinking water treatment. Results of performed thermogravimetric analysis, derivative thermogravimetric analysis, and differential thermal analysis, enabled a number of hypotheses to be made about different phases of activated carbon regeneration, values of characteristic parameters during particular process phases, as well as catalytic impact of inorganic materials on development of regeneration process. Samples of activated carbon were heated up to 1000?C in thermogravimetric analyser while maintaining adequate oxidizing or reducing conditions. Based on diagrams of thermal analysis for samples of spent activated carbon, temperature intervals of the first intense mass change phase (180-215?C), maximum of exothermic processes (400-450?C), beginning of the second intense mass change phase (635-700?C), and maximum endothermic processes (800-815?C) were deter-mined. Analysing and comparing the diagrams of thermal analysis for new, previously regenerated and spent activated carbon, hypothesis about physical and chemical transformations of organic and inorganic adsorbate in spent activated carbon are given. Transformation of an organic adsorbate in the pores of activated carbon, results in loss of mass and an exothermic reaction with oxygen in the vapour phase. The reactions of inorganic adsorbate also result the loss of mass of activated carbon during its heating and endothermic reactions of their degradation at high temperatures.
Computational fluid dynamic analysis on the effect of particles density and body diameter in a tangential inlet cyclone heat exchanger
Authors: Thulasiraman Mothilal , Kasiviswanathan Pitchandi
Published: March 2016

This work presents the effect of particles density and body diameter on hold up mass and heat transfer rate in cyclone heat exchanger by using CFD analysis. Performance of cyclone heat exchanger is based on operational and geometrical parameters which mainly depend on inlet air velocity and solid particles parameters. Present work studies the effect of particles density, diameter of cyclone, inlet air velocity, and temperature on performance of cyclone heat exchanger. The RNG k-? turbulence model was adopted in ANSYS FLUENT 12.0 software to analyze the flow field and discrete phase model is adopted to predict tracking of solid particles in cyclone. Solid particles density ranges from 2050 to 8950 kg/m3 for different materials fed at 0.5 g/s flow rate and inlet air velocity ranges from 5 to 25 m/s at three inlet air temperature 373, 473, and 573 K for 100, 200, and 300 mm body diameter cyclone heat exchangers. Results conclude that increase in diameter of cyclone increases hold up mass and heat transfer rate whereas increase in density of particles decreases the hold up mass and heat transfer rate. Experimental set-up was built for Stairmand high efficiency cyclone and good agreement was found between simulation and experimental result. New correlation was proposed for non-dimensional hold up mass. Correlation compared with experimental hold up mass and predicts experimental value within an error band of ?3 to 6%.
Epidemiology and structure of congenital anomalies of the newborns in the region of Novi Sad (Vojvodina, Serbia) in 1996 and 2006
Authors: Ristivojevic Andjelka , Lukic-Djokic Petra , Katanic Dragan , Dobanovacki Dusanka , Jovanovic-Privrodski Jadranka
Published: March 2016

Background/Aim. According to the World Health Organization (WHO) definition,
congenital anomalies are all disorders of the organs or tissues, regardless
of whether they are visible at birth or manifest in life, and are registered
in the International Classification of Diseases. The aim of this study was to
compare the incidence and structure of prenatally detected and clinically
manifested congenital anomalies in the newborns in the region of Novi Sad
(Province of Vojvodina, Serbia) in the two distant years (1996 and 2006).
Methods. This retrospective cohort study included all the children born at
the Clinic for Gynecology and Obstetrics (Clinical Center of Vojvodina) in
Novi Sad during 1996 and 2006. The incidence and the structure of congenital
anomalies were analyzed. Results. During 1996 there were 6,099 births and
major congenital anomalies were found in 215 infants, representing 3.5%. In
2006 there were 6,628 births and major congenital anomalies were noted in 201
newborns, which is 3%. During 1996 there were more children with anomalies of
musculoskeletal system, urogenital tract, with anomalies of the central
nervous system and chromosomal abnormalities. During the year 2006 there were
more children with cardiovascular anomalies, followed by urogenital
anomalies, with significant decline in musculoskeletal anomalies. The
distribution of the newborns with major congenital anomalies, regarding
perinatal outcome, showed the difference between the studied years. In 2006
the increasing number of children required further investigation and
treatment. Conclusions. There is no national registry of congenital anomalies
in Serbia so the aim of this study was to enlight this topic. In the span of
ten years, covering the period of the NATO campaign in Novi Sad and Serbia,
the frequency of major congenital anomalies in the newborns was not
increased. The most frequent anomalies observed during both years implied the
musculosketelal, cardiovascular, urogenital and central nervous system. In
the year 2006 there was a significant eruption of cardiovascular anomalies
and a significant decrease of musculoskeletal anomalies, chromosomal
abnormalities and central nervous system anomalies, while the number of
urogenital anomalies declined compared to the year 1996.
Increased accuracy of single photon emission computed tomography (SPECT) myocardial perfusion scintigraphy using iterative reconstruction of images
Authors: Stevic Milos , Vlajkovic Marina
Published: March 2016

Background/Aim. Filtered back projection (FBP) is a common way of processing
myocardial perfusion imaging (MPI) studies. There are artifacts in FBP which
can cause falsepositive results. Iterative reconstruction (IR) is developed
to reduce false positive findings in MPI studies. The aim of this study was
to evaluate the difference in the number of false positive findings in MPI
studies, between FBP and IR processing. Methods. We examined 107 patients
with angina pectoris with MPI and coronary angiography (CAG), 77 man and 30
woman, aged 32?82. MPI studies were processed with FBP and with IR. Positive
finding at MPI was visualization of the perfusion defect. Positive finding at
CAG was stenosis of coronary artery. Perfusion defect at MPI without coronary
artery stenosis at CAG was considered like false positive. The results were
statistically analyzed with bivariate correlation, and with one sample
t-test. Results. There were 20.6% normal, and 79.4% pathologic findings at
FBP, 30.8% normal and 69.2% pathologic with IR and 37.4% normal and 62.6%
pathologic at CAG. FBP produced 19 false-positive findings, at IR 11 false
positive findings. The correlation between FBP and CAG was 0.658 (p < 0.01)
and between IR and CAG 0.784 (p < 0.01). The number of false positive
findings at MPI with IR was significantly lower than at FBP (p < 0.01).
Conclusion. Our study shows that IR processing MPI scintigraphy has less
number of false positive findings, therefore it is our choice for processing
MPI studies.
Evaluating empathy in adolescents with conduct disorders
Authors: Kostic Jelena , Nesic Milkica , Stankovic Miodrag , Zikic Olivera , Markovic Jasminka
Published: March 2016

Background/Aim. According to currently available data, there is no research
dealing with evaluating empathy in adolescents with conduct disorders in our
region. The aim of the research was to examine the differences in the
severity of cognitive and affective empathy in adolescents with and with no
conduct disorder, as well as to examine the relationship between cognitive
and affective empathy and the level of externalization in adolescents with
conduct disorder. Methods. This research was conducted on 171 adolescents,
aged 15 to 18, using the Interpersonal Reactivity Index, Youth Self- Report
and a Questionnaire constructed for the purpose of this research. Results.
The results showed that adolescents with conduct disorder had significantly
lower scores for Perspective Taking (t = 3.255, p = 0.001), Fantasy (t =
2.133, p = 0.034) and Empathic Concern (t = 2.479, p = 0.014) compared to the
adolescents in the control group, while the values for Personal Distress (t =
1.818, p = 0.071) were higher compared to the control group, but the
difference was not statistically significant. The study showed a
statistically significant negative correlation between Perspective Taking and
aggression (r = - 0.318, p = 0.003) and a negative correlation between
Perspective Taking and the overall level of externalizing problems (r =
-0.310, p = 0.004) in the group of adolescents with conduct disorder.
Conclusion. This research contributes to better understanding of behavioral
disorders in terms of individual factors, especially empathic reactivity.
Preventive work with young people who have behavioral problems associated
with empathy deficit disorder proved to be an important tool in preventing
the development, or at least relieving the symptoms, of this ever more common
disorder.
Good Old Gamers, Good Drivers: Results from a correlational experiment among older drivers
Authors: Vichitvanichphong Suchada , Talaei-Khoei Amir , Kerr Donald , Ghapanchi Amir Hossein , Scott-Parker Bridie
Published: March 2016

In many situations, driving is essential for senior citizens to maintain their independent lifestyle. A systematic literature review was conducted that summarized the age-related physical, visual and cognitive functional declines and their associated risk to driving. Based on these findings, we explored whether the skills required in playing Xbox Kinect video games were correlated with measures of driving performance among older drivers. Fifty-two participants, 65 years of age or older (Mean = 72; SD = 3.84; range 65 – 85 years; 29 males) who have access to a car and drive frequently were invited to play Just dance, Table Tennis (ping pong), Bowling, and Dr Kawashima’s Brain Training Exercises on an Xbox Kinect 360. Participants also completed a 25-minute on-road driving task along a predetermined route to assess and identify critical driving errors using a similar instrument as that used by a driving license tester. Bivariate correlation examined the relationship between game scores and these objective driving skills. There was a significant correlation between the Xbox Kinect video games and on-road driving scores (r = 0.861, p <0.001), indicating that ‘good gamers are good drivers’. This was correlation was significant for the males (r = 0.864, p <0.001) as well as for the females (r = 0.878, p <0.001). We suggest that performance on Xbox games may be a suitable, cost-effective and less-risky indicator of on-road driving skills for older drivers, particularly in jurisdictions in which mandatory testing of older citizens has been introduced or is being considered as a requirement in the driver licensing process.
Optoelectronic Devices Based on Atomically Thin Transition Metal Dichalcogenides
Authors: Pospischil Andreas , Mueller Thomas
Published: March 2016

We review the application of atomically thin transition metal dichalcogenides in optoelectronic devices. First, a brief overview of the optical properties of two-dimensional layered semiconductors is given and the role of excitons and valley dichroism in these materials are discussed. The following sections review and compare different concepts of photodetecting and light emitting devices, nanoscale lasers, single photon emitters, valleytronics devices, as well as photovoltaic cells. Lateral and vertical device layouts and different operation mechanisms are compared. An insight into the emerging field of valley-based optoelectronics is given. We conclude with a critical evaluation of the research area, where we discuss potential future applications and remaining challenges.
Effects of Strong East Asian Cold Surges on Improving the Air Quality over Mainland China
Authors: Wang Zhaosheng , Liu Xiaodong , Xie Xiaoning
Published: March 2016

A strong East Asian cold surge (SEACS) is one of the most distinct extreme weather events that can promote an improvement in local air quality. Combining East Asian atmospheric circulation with the air pollution index (API) datasets of 47 major cities throughout mainland China in 11 winter half-years (November–March) during 2001/2002–2011/2012, we investigated the influence of 39 SEACSs in conjunction with air pollution episodes on air quality over mainland China. The results showed that SEACS can cause considerable improvement in air quality and a remarkable decrease in the API over mainland China in up to 4 days after the SEACS outbreak day. The removal efficiency of air pollutants by SEACSs was greater than 30% in north central China, eastern southwest China, and southeast China. The occurrence date of the lowest value of the local API (indicating the best local air quality) can be observed as late day by day from northwest to southeast over mainland China after the SEACS outbreak, indicating a process of gradual improvement in Chinese air quality after the SEACS outbreak. When clean cold air originating from Siberia moves southward into coastal areas of southeastern China, the increase in sea level pressure, the drop in temperature and the enhancement in the northerly wind also tend to progress gradually from north to south over SEACS-affected East Asia. Thus, the “early in the north and late in the south” feature of air quality improvement by SEACSs over mainland China results from the southward movement of cold air masses from high to low latitudes after cold surge outbreaks.
Effect of Porphyrin Molecular Structure on Water Splitting Activity of a KTaO3 Photocatalyst
Authors: Hagiwara Hidehisa , Higashi Kohei , Watanabe Motonori , Kakigi Ryota , Ida Shintaro , Ishihara Tatsumi
Published: March 2016

Photocatalytic water splitting is one of the ideal methods for solving the global energy crisis and its associated environmental problems. In this study, the effect of altering the molecular structure of porphyrins was investigated to improve the water splitting activity of Zr-doped KTaO3 (KTa(Zr)O3) modified with porphyrin dyes. UV-vis spectra indicated that porphyrins with long alkoxy chains tended to form well-developed H-aggregates on the KTa(Zr)O3 surface. The photocatalytic activity of Pt-loaded KTa(Zr)O3 was improved by using porphyrins with longer alkoxy chains because of the improvement in the charge migration between porphyrin dye molecules. While the charge transfer between the inorganic semiconductor and porphyrin dye interface is important, it was found that the formation of H-aggregation was more effective in improving the water splitting activity of the porphyrin-modified photocatalysts.