bluuebunny/crossref_metadata_2025 huggingface dataset:
Unlocking Resource Plays in Egypt - Opportunities and Challenges
Authors: Carnell Andrew , Emam Mourad , Boering Martijn
Published: April 2013

Resource plays are at the centre of worldwide attention following the rapid growth in tight and shale gas production in North America over the last 5 years. This paper examines the opportunities and challenges that the exploration, appraisal and development of resource plays can bring to Egypt. Resource plays are defined in this paper as "technically difficult to extract" hydrocarbons found in tight sandstones, carbonates and shales.

As the energy demand is increasing in Egypt and oil and gas production from the conventional development asset base is declining, resource plays may hold the future for Egypt's energy supply. Resource plays are attractive because they typically have relatively low exploration risks, material in-place and recoverable volumes, long lasting production and can often utilize available ullage in existing infrastructure and facilities. Unlocking these plays, however, also pose significant challenges.

This paper will 1) summarize learning's from North America projects and how they may apply in Egypt, 2) investigate the key technical challenges of resource plays and 3) examines the current regulatory and contractor landscape and its opportunities and hurdles for resource plays.
Gas Shale Characterization - Results of the Mineralogical, Lithological and Geochemical Analysis of Cuttings Samples from Radioactive Silurian Shales of a Palaeozoic Basin, SW Algeria
Authors: Hofmann Andreas , Rigollet Christophe , Portier Eric , Burns Suzi
Published: April 2013

The successful recovery of hydrocarbons from shales is dependent on physical rock properties such as lamination, brittleness and the presence of natural fractures, as well as chemo-physical properties such as absorption and adsorption. The key parameters defining the hydrocarbon potential of shales are the mineralogy, organic carbon content (TOC) and burial history. These parameters are commonly derived by conventional and special core analysis of SWCs or cores.

This study highlights that most of the analyses and techniques used to determine the hydrocarbon potential of shales can also be performed on cuttings material with a high degree of confidence. The usage of cutting material has significant advantages with respect to sample availability, sample coverage and acquisition costs. Accurate depth allocation of cuttings is problematic but, by careful reference of the measured mineralogical and textural features to the available mudlog and wireline data, the effects can be minimised.

As part of a research project, SGS analysed the mineralogical and lithological composition of 80 cuttings samples, from various wells in the Radioactive Silurian Shale (drilled a Palaezoic Basin, SW of Algeria) by QEMSCAN. In addition, the geochemistry and maturity parameters were determined by Leco (TOC) and RockEval (S1-S3) methods. Furthermore high resolution 3D computer tomography scans (CT) were performed in order to analyse the cutting material for lamination and micro-fractures. The compilation and interpretation of the mineralogical, lithological and geochemical data indicate significant vertical and lateral heterogeneities, probably induced by local facies changes, which possibly lead to strong variances in the shale gas potential.

The properties of the Silurian hot shale samples were compared with QEMSCAN results of shale samples from Canada, UK, published data from the US gas shales and source rocks from Netherlands and Sweden. Based on the comparison, a distinct trend could be established, indicating significant differences in mineral composition between producing gas shales and other more "conventional" gas source rocks.
Pre-Messinian Extensional Tectonics and exploration potential of related structures; in Central Nile Delta Basin, Egypt
Authors: Matresu J.. , Talaat A.. , El Belasy A. M. , El-Meadawy M..
Published: April 2013

This paper discusses the exploration potential of extensional structures in pre-Messinian formations in central Nile Delta Basin. The study aims at detailed description of extensional events and discusses the exploration potential of specific structures generated.

Particularly, structural elements of pre-Messianian sequences were partially deciphered in the past, due to quality of seismic data and spare and scarce wells drilled to these levels. The newly acquired high quality 3D seismic data has been able to improve the image underneath the pre-Messinian. This has resulted in the understanding of tectonic activity, faults system and structures developed.

Two extensional events characterize the tectonic activity in the Late Oligocene through Messinian.

First extensional event is related to onset of Gulf of Suez rifting and generate a W-E system of basement involved faults and reactivation of syn-rift hinge zone. Related structures of this extensional phase are represented by growth anticline, drag folds and rotated blocks.

The second extensional tectonic event occurred in Tortonian. The structural style corresponds to tilted and eroded fault blocks dipping to north and being aligned in a north- south direction corresponding to the main normal faults trend.

This study of the pre-Messinian extensional structures described here will have a direct impact on the exploration activities design, several important prospects being delineating among the structures developed during both extensional phases.
Gas chimneys and their impact on gas migration, accumulation and de-risking of prospects, offshore Nile Delta - Central Sub Basin.
Authors: El Belasy A. M. , Talaat A.. , Matresu J..
Published: April 2013

Baltim Concession is a large exploration/exploitation license located in the offshore Nile Delta, Egypt. The concession covers an area of 430 Km2 of the central portion of the present day Nile delta cone. High quality three dimensional (3D) seismic data, coupled with data from some wells drilled in the area, have highlighted the presence of some gas chimneys well recognizable started from pre-Messinian until the Plio-Pleistocene slope succession.

The geometry and architecture of the gas chimneys in Baltim area have been imaged by 3D seismic techniques, time section and a variety of attribute extractions, providing us with a high resolution definition of these features.

The main indicator for gas chimneys in seismic is an almost cylindrical shaped chaotic behavior of seismic signal, due to scattering of seismic energy by diffused gas through the cap rocks above the leaked reservoirs. The origin of gas chimneys has to be related to hydraulic fracturing by gas leaking through faults from deep accumulation where overpressure conditions have been generated by fast burial during the Plio-Pleistocene mega sequence deposition.

The petroleum system in Post-Messinian (Plio-Pleistocene) succession generated biogenic gas only, whereas the Pre-Messinian system proved to generate thermogenic gas and oil.

The role of gas chimney and associated structures as hydrocarbon migration pathways from the pre-Messinian kitchen section to the Post-Messinian reservoirs is testified by many DHI's within the Pliocene – Pleistocene reservoirs that are in contact with the boundaries of the gas chimneys.

In addition, geochemical analysis on gas samples from targets drilled in the Pliocene – Pleistocene indicates the presence of thermogenic gas clearly generated from pre-Messinian units.

From isotopic data, PVT samples and production data from gas fields discovered in Plio-Pleistocene succession evidenced that in many cases gas migrated from the pre-Messinian through high fracture zones related to gas chimneys activities in the studied area.
Applications of Nanotechnology in the Oil & Gas Industry: Latest Trends Worldwide & Future Challenges in Egypt
Authors: El-Diasty Abdelrahman Ibrahim , Ragab Adel M.
Published: April 2013

Nanotechnology has become the buzz word of the decade! The precise manipulation and control of matter at dimensions of (1-100) nanometers have revolutionized many industries including the Oil and Gas industry. Its broad impact on more than one discipline is making it of increasing interest to concerned parties.

The Nanotechnology applications have pierced through different Petroleum disciplines from Exploration, to Reservoir, Drilling, Completion, Production and Processing & Refinery. For instance, Nano-sensors have been developed rapidly to enhance the resolution of the subsurface imaging leading to advanced field characterization techniques. Nanotechnology also strikes the stage of production enormously to enhance the oil recovery via molecular modification and manipulate the interfacial characteristics. Moreover, in a very similar fashion, it provides novel approaches to improved post production processes.

Only very few publications were able to report the latest accomplishments in different Petroleum Engineering domains. This paper provides an overview of the latest Nano-technological solutions in the O&G industry and covers the recent research developments that have been carried out around the world and paves the way for many researchers and organizations who are interested in the integration of these technological advancements, to discover the challenges and the revolution that Nanotechnology is about to bring to O&G Industry in Egypt.

Egypt's domestic demand for oil is increasing rapidly. Oil consumption has grown by more than 30% in the past ten years. Also, the hydrocarbon reserves in Egypt have witnessed an average increase of 5%/year over the past seven years, while the average recovery factor is still stuck at the 35%. Nanotechnology holds the key solution to this local production challenge as it helps increase the recovered Oil and decrease the cost of production by eliminating problems that occur throughout the field development operations.
A Road Map For Integrating a Giant Field: Case Study
Authors: Darhim M. Noureldien , Nassar Ibrahim , Salah Nabil , Mamdouh Mostafa , Merghany Ibrahim , Hassan Ahmed , Sobhy Mahmoud , Gamil Mohamed , Nabil Mohammed
Published: April 2013

El-Morgan Field was discovered in 1965 and is located offshore in the Gulf of Suez (GoS) approximately 160 miles south of Suez, Egypt. Peak Production was approximately 300,000 BOPD within only three years. El- Morgan is considered one of the giant fields since its STOOIP is estimated to be approximately 2.689 billion BO with an ultimate recoverable reserve around 1.439 billion BO. Over its history, more than 250 wells were drilled. Currently, 179 wells are operating (125 producers & 54 Injectors).

El-Morgan is considered highly sophisticated field due to reservoir heterogeneity (Kareem reservoir), moderate stratification, limited aquifer support, high bubble-point pressure, low-permeability layers and its friable sand. Due to the high bubble-point pressure and high initial-rate (Pi=2,990psi & PB=2,269psi), the bubble-point pressure was encountered early in the field resulted in using peripheral injection to support reservoir pressure. In addition the reservoir heterogeneity while injecting peripherally, it is believed that significant oil reserves were being bypassed and were potentially unrecoverable.

This paper presents an integrated approach to optimize the development for a complex field from both subsurface and operations views. It also shows studies conducted to maximize the asset value, explains how the development strategy have been revised over time, to augment oil ended by using an EOR method nowadays (BrightWaterTM). All of these studies are coupled to the economical calculations.

Managing giant fields with a significant potential is very important since each incremental 1% in RF will increase the ultimate recovery by tens of millions oil barrels. Also through this paper you will assure importance of certain reservoir evaluation tools and how you can optimize them to increase ultimate recovery factor. Paper is an excellent example for reservoir management that resulted in more than 52% primary RF.
High Resolution Saturation Analysis in Nile Delta Turbiditic Sands from Imaging Tool Resistivity and NMR in Oil-Based Mud
Authors: Salah A.. , Sabra M.. , Said M.. , Van Steenes M.. , Haddad E..
Published: April 2013

Porosity, water saturation, and net-to-gross evaluation can be challenging in thinly bedded sands. The use of standard induction resistivity for formation evaluation can lead to the overestimation of water saturation. This work explores the following options to improve formation evaluation in these conditions: the use of high resolution density and nuclear magnetic resonance (NMR) data to improve porosity vertical resolution; the use of high-resolution resistivity from an oil-based-mud microresistivity imaging tool in improving the saturation computation (Sw); and the comparison of imaging tool resistivity-based sand count and NMR-based thin-bed fraction.

Using high-resolution porosity inputs from density and NMR provided a porosity curve with a better vertical resolution to match the high resolution resistivity from the imaging tool. It also identified additional productive thin beds compared to the standard resolution outputs and allowed computation of a high-resolution irreducible water saturation.

The induction-based Sw is strongly affected by shoulder bed effect and overestimates Sw by approximately 10 to 15%. The high-resolution curve from the imaging tool was used as an input into the Sw computation, which was made possible by shallow oil-based mud (OBM) invasion. This approach gave good results in beds thicker than 6 in., where Sw from the imaging tool matches the irreducible water saturation computed from NMR, giving 20 to 30% Sw.

A thin-bed fraction curve was computed from the NMR data. It shows a good match with the image-based high resolution- sand count and the image features, demonstrating that NMR and the imaging tool are equally able to identify and quantify thin beds, even though they have different vertical resolutions. This study showed that the microresistivity imaging tool and NMR are essential tools to characterize thinly bedded reservoirs.
The Use of Thermodynamic Reservoir Simulation to Investigate the Feasibility of Steam Flooding to Improve Oil Recovery in A Light Oil Reservoir
Authors: Al-Mudhafer Wathiq J.
Published: April 2013

Thermal oil recovery methods have been widely used not only in heavy oil reservoirs, but also in light oil reservoir with Waterflooding to improve oil recovery. The Steamflooding could be considered as an effective way to enhance the oil displacement especially in heterogeneous reservoirs The field, of 58-years of production history, is located in South of Iraq. It has 40 producing wells. There was an infinite active aquifer located at the east and west flanks. The strength of this aquifer from the west flank is much larger than its in the east flank because the reservoir permeability at the eastern boundaries is lower than as at the western one for all the layers; therefore, Twenty injection wells were drilled at the east flank to maintain the aquifer water approaching to the reservoir. The average surface area for this reservoir is 142 km2 and average formation depth of 10350 ft subsea with a maximum vertical oil column of 350 ft. Average porosity is 21%. The oil is 34°API with an average initial bubble point pressure of 2660 psia. Current reservoir pressure is approximately 4200 psia and the reservoir temperature is 210°F. In this study, a thermodynamic reservoir simulation has been adopted to investigate the competence of Steamflooding to improve oil recovery.

The objective of this work was to examine the feasibility of steam-injection processes, so a thermodynamical reservoir model (CMG-STARS) has been applied to demonstrate the effect of using steam injection as a heating agent to increase the sweep efficiency in this heterogeneous formation. The twenty injection wells have been converted to steam injection for twelve future prediction years. The process has demonstrated a considerable increase of the cumulative oil production. This result has been compared with the base scenario of water injection at the same injection rates of 10,000 STB/DAY per well. The water injection scenario has been done by CMG-IMEX. This incremental has been proved over most of the production wells that have distributed among the reservoir by showing a significant difference between the two cases.
Pressure Transient Data from Wireline Formation Testers : When and How to use it?
Authors: Ramaswami S.. , Hows M.. , Frese D.. , Dong C.. , Elshahawi H..
Published: April 2013

The use of pressure transient data in the field of Formation Testing in efforts to describe productivity and permeability of reservoirs is considered mature technology, particularly when applied to data collected through production testing. The extension of this technique to data obtained using Wireline Formation Testers, where either a single probe or a straddle packer is used to propagate a pressure pulse into a reservoir, has been gaining momentum in the industry over the past decade, however the integration of these outputs with other measurements of rock and fluid data is not always straight forward. This paper presents different methods of using pressure transient data from Wireline Formation Testers such as quantitative permeability determination, identification of permeability discrepancies in homogenous clastic formations, upscaling of permeability in a complex stacked reservoir and comparison of Wireline Formation Tester and conventional well test derived permeabilities. Additionally, this paper highlights the challenges one faces while planning, acquiring and interpreting pressure transient data from Wireline Formation Testers, as well as the importance of real-time monitoring and control of data.
Comparative Study of Miscible Flooding in Compositional Graded Reservoir System
Authors: Hossain Mohammad Sohrab
Published: April 2013

Miscible gas injection in near critical oil or volatile oil reservoir improves the recovery due to interfacial tension effects and better microscopic displacement efficiency compared to immiscible water injection. In a graded undersaturated gas-oil fluid system, all fluids are initially first contact miscible with neighboring fluids throughout the reservoir if full- pressure maintenance is supported by injection process.

Smorbukk south is characterized as a compositionally graded gas condensate and volatile oil reservoir which lies near the critical region in the phase diagram. Compositional graded reservoir systems exhibit significant variation in the minimum miscible pressure (MMP). MMP variations with depth pose a challenge in selecting reservoir recovery technique to maximize the ultimate recovery.

This paper deals with different scenarios of miscible flooding and compares the results with immiscible flooding for a 3-D homogeneous reservoir system. Here, MMP, determined by different injection gases, can develop far below the saturation pressure. If the injectant is CO2 or sufficiently enriched with intermediate components, the condensing and vaporizing (C/V) mechanism was developed throughout the reservoir. Dipping effects and placement of injector -producer were studied here and was found that updip formation gives highest recovery. Various injection schemes (i.e. Separator Gas and CO2) were studied in miscible flooding scenarios. The results of gas alternating gas (GAG) were compared with the water alternating gas (WAG) method and GAG was found to be the best alternative.
Application of Relative Permeability Modifier for Sealant Diversion
Authors: Das Prasanta , Patil Prajakta , Agashe Snehalata
Published: April 2013

Organically crosslinked polymer (OCP) systems are well-known sealants used for water shutoff in conformance applications. However, in multizone treatments with significant differences in permeability, a diverter is essential to divert the sealant to shut off less-permeable zones. This paper investigates the use of a relative permeability modifier (RPM) as a diverter for the sealant. This solution is most effective at shutting off zones in cases where multiple water-bearing strata with different permeability are encountered. The sealant is proven to be effective, even at 400°F.

Two sandpacks of different permeabilities were formulated. All diversion tests were performed at room temperature and without any backpressure. The RPM adsorbed to the high-permeability zone more than the low-permeability zone. Once adsorbed, the RPM hindered flow of the water-based sealant in the high-permeability zone and diverted it to the low-permeability zone. With higher flow rates, the effect of diversion was lower because more sealant in the low-permeability pack provided resistance for further penetration of the sealant. The RPM and sealant were mixed at different ratios and tested under high-pressure/high-temperature (HP/HT) conditions to observe the effect of mixing on the gelation time for the sealant. The effect of the RPM on gelation time for the sealant was insignificant, provided the polymer and crosslinker concentration of the sealant was constant.

RPMs have been widely applied to decrease the permeability to water in oil and gas wells. RPMs have also been used for acid diversion. The current study shows a new application of using RPMs as a diverter for sealants. This investigation will help increase the potential areas where multizone shutoff using a sealant treatment can be used.
Importance of Surveillance for Evaluating a New Reservoir Technology
Authors: Gobran Mahmoud H. , Kinawy Mahmoud M. , Bayoumi Radi S , Shahin Eman S
Published: April 2013

Morgan is the largest field in Gulf of Suez Egypt. It started production in April 1967. Morgan comprises two main reservoirs; Kareem and Belayim. Both reservoirs have weak aquifer support. Waterflooding was implemented in February 1974 to support the depleted reservoir energy and improve the sweep efficiency. Currently the field is mature and most of wells are producing with high water cut.

Kareem reservoir is heterogeneous and there is a high permeability variation between different layers and most of the injected water goes to high permeable layers.

BrightWater ™1 technology was developed to create baffles in the higher permeability layers to divert the injected water from previously swept layers to the un-swept zones which will improve the sweep efficiency.

North Morgan Kareem reservoir selected as a pilot for BrightWater deployment by treating five injectors which are impacting on ten producers. BrightWater uses a temperature activated cross-linked polymer carried with the injected water. Their distribution within the reservoir is proportion to the distribution of injected water. As the injected water moves away from the injection wells it is warmed by reservoir rocks. This rise in temperature causes the BrightWater chemical to activate and pop up to plug the higher permeability zones.

A complete evaluation for BrightWater is very important to define its value to be applied in other fields. Different surveillance tools were selected for Brightwater evaluation. These surveillance tools are summarized in: chemical Tracer detecting, well-testing, water cut measuring, pressure fall-off / step-rate testing, injectivity monitoring, and production / injection logging. All of these surveillance tools will be used in the three phases of BrightWater treatment; before popping, at popping, and after popping.

This paper will provide the BrigtWater technique principle for enhancing the sweep efficiency, the optimum surveillance tools to evaluate its impact and a real case history for North Morgan Kareem reservoir.
Integrated Reservoir Study of Mature Oil Field Resulted in Rejuvenation of an Abandoned Oil Reservoir to Add New Reserves and Production, GoS - Egypt
Authors: Gamal M. , Raafat M. , Thabt M. , Allam F. , Farouk H.
Published: April 2013

An integrated reservoir study was initiated to look for new opportunities in East Zeit field. The working team managed to construct the full field static and dynamic models. The main challenge during the history match phase was the high complexity of the structure, range of uncertainties, and the model running time. The team managed to understand unconventional reservoir aspects such as:

(1) The reservoir pressure was sharply decreases as production increases. Then, when the reservoir was abandoned as a depletion drive reservoir the pressure started to increase up to initial reservoir pressure without any intervention.

(2) The performance of few wells completed in the above mentioned reservoir was similar to the performance of wells in active water drive reservoirs.

Comprehensive work in the history match has been done to calibrate the model and explain the different phenomena in the field. The team explained the pressure increase in the depleted reservoir that it was due to the reactivation of faults which became non-sealing. This resulted in communication with another active water drive reservoir and natural miscibility process. The study recommended adding new off take point in the reservoir to confirm the concept. So, a new well was drilled and confirmed the study conclusion and managed to add more reserves and production in the rejuvenated reservoir after 12 years of shut in. Currently, constructing complete field development plan is in progress to maximize the recovery factor. Reservoir monitoring even after abandonment, especially with unconventional reservoir aspects, is very important to discover new opportunities and maximize the recovery. These opportunities should be managed through the integrated reservoir simulation studies to minimize the risk and cover the uncertainties.

Introduction

The East Zeit field (EZ) is situated in the southern Gulf of Suez (GoS) in about 240 ft of water (Fig.1). The oil accumulation in the field covers an approximately 27 km2 area. The field is composed laterally of two major fault blocks; the main fault block (MFB) and the east fault block (EFB). Moreover, each major fault block is sub-divided into smaller fault blocks which reflect the complexity of the highly faulted structure. Each major fault block is sub-divided vertically into three main reservoirs (Fig.2). The field was started production in 1985 through two platforms; the wells were flowing naturally in the past and currently some wells are producing by artificial lift and other wells are still flowing naturally.
Experimental Investigation of Low Salinity Hot Water Injection to Enhance the Recovery of Heavy Oil Reservoirs
Authors: Abass Elradi , Fahmi A..
Published: April 2013

Many laboratory core flood investigations have shown increased oil recovery is achieved by water flooding applying low salinity water, compared with injection of high salinity produced water or brine seawater. This work describes a sand pack flood test, designed to identify whether this process could be observed as additional mechanism to thermal drive mechanism as a new technique for heavy oil displacement. The core and sand pack flood test was schematically designed and conducted, to ensure that the results achieved concerning the salinity alteration under stabilized thermal displacement conditions, The result confirms a significant increase in oil recovery due to hot water low salinity injection. In all experiments done, approve the effect of low salinity as an additional to thermal recovery mechanism of heavy crude oil when applied to the residual oil after high salinity hot water flood. It would indicate that more than 25 percent additional oil would be recovered by low salinity as additional mechanism to hot water flooding. The studies have been conducted mainly for heavy oil from BAW Sudan oil field, under current reservoir conditions. Detailed benefits regarding to this technique is presented concerning to enhance oil recovery in BAW oil field.
Life Cycle Concept (LCC) in Waste Management in the O&G Offshore Exploration
Authors: Burlini Patricia Soares , Araruna José Tavares
Published: April 2013

There is a general belief that the oil industry has its activities incompatible with the concept of sustainable development. However, the development of humanity has been based on power consumption; much of them are provided by this industry. With the new exploratory oil & gas (O&G) frontier in Brazil, the pre-salt, it is possible to envision that the operating segment will be very present in the country, as well as their negative impacts to the environment and its tons of waste that will be generated. This paper seeks to promote reflection on the theme discussing the concept of life-cycle thinking (LCT). The application of life-cycle thinking to waste management brings a differential for long-term reduction of pollution, by facilitating the analysis of various aspects including the necessary infrastructure for managing legal matters (i.e., licensing) and logistics. LCT still promotes a better understanding for the general public, regulators, operators and companies providing services. It even allows companies in Brazil to be better prepared for the challenges related to the pollution generated by O&G offshore exploration wastes.
Comparison of different methods for extracting bone cross-sectional geometric properties from CT images
Authors: Ilic Sinisa , Timotijevic Sladjan , Lazovic Dejan , Spalevic Petar , Veljovic Alempije
Published: April 2013

Analysis of the geometric properties of bone cross-sections is often used to
determine skeletal performance and the ability of the body to resist
different external forces. This analysis is dependent on obtaining adequate
bone cross-sectional images. CT images can be used for this purpose by
performing some pre-processing of images in order to achieve sufficient
accuracy. In this paper we have used experiments to show that relatively good
accuracy of bone cross sectional areas and moments of inertia can be achieved
by simple threshold level filtering of CT images.
Knowledge and Attitudes of Health Care Workers from the Primary Health Centre in Inđija, Serbia on Professional Exposures to Blood-borne Infections
Authors: Gajić Zdenko , Rajčević Smiljana , Đurić Predrag , Ilić Svetlana , Dugandžija Tihomir
Published: April 2013

Exposure to blood-borne infections (HIV, hepatitis B, hepatitis C) poses a serious risk to health care workers (HCWs). The aim of this cross-sectional study was to determine the level of knowledge and attitudes on occupational exposure in primary health care. In 2009, a total of 100 health care workers from the Primary Health Care Centre in Inđija, Autonomous Province of Vojvodina, Serbia were included in the study. The results suggested that the health care workers who participated in the survey possess basic knowledge about blood-borne virus transmission routes. Most incorrect answers were related to the transmission of blood-borne viruses by tears, saliva, urine and stool. This study also demonstrated that health workers tend to unrealistically estimate the risk of HIV infections. As for the level of education about the prevention and control of blood-borne infections, 49 % of the participants had never had any education on this topic, while 22 % had been educated during the last five years. Around 75 % consider education on blood-borne infection and protective measures at work unnecessary.
Influence of Vibrations During Crystallization on Mechanical Properties and Porosity of EN AC-AlSi17 Alloy
Authors: Ciućka T.
Published: April 2013

Today’s industry aims at such situation, where number of defective products, so called defects shall approach to zero. Therefore, one introduces a various changes in technology of production, introduces improvements which would help in accomplishment of this objective. Another important factor is introduction of different type of testing, which shall help in assessment which factor has significant effect on quantity of rejects, and which one could be neglected. Existence of casting rejects is unavoidable; therefore a new ideas, technologies and innovations are necessary in the entire widely understood foundry branch, in order to minimize such adverse effect. Performance of tests aimed at unequivocal determination of an effect of vibrations during crystallization on mechanical properties and porosity of the EN ACAlSi17 alloy was the objective of the present work. To do this, there were produced 36 castings from EN AC-AlSi17 alloy. All the castings underwent machining operations. Half of the casting was destined to strength tests, the other half served to determination of an effect of vibrations on porosity of the alloy. The specimens were divided into 12 groups, depending on amplitude of vibrations and tilt angle of metal mould during pouring operation.
Test Bench for Analyzing the Lost Foam Process
Authors: Kaczorowski R. , Just P. , Pacyniak T.
Published: April 2013

The current work presents and describes the test bench for analyzing the lost foam process, especially measuring of the pressure of gases in the gas gap and continuous measuring of the rate of rise of the bath level when pouring the liquid metal into the mould. A series of preliminary research was carried out on the bench which was aimed at determining the influence of the basic parameters of the process, i.e. the density of the styrofoam pattern, thickness of the refractory coating applied on the pattern, kind of the alloy and the temperature of pouring on the mould cavity by the liquid metal and the pressure of gases in the gas gap.
Investigations of the Influence of the Matrix Recycling on Properties of the Moulding Sand with Geopol 618 Binder
Authors: Kamińska J.
Published: April 2013

Self-hardening moulding sands with water-glass hardened by liquid esters are applied in several foundry plants for making moulds for the production of heavy iron and steel castings. The main good point of this process is a low cost of sands. However, on account of a low susceptibility of this moulding sand for the matrix reclamation the fraction of sands originated from the reclamation is limited. The investigations presented in this work were aimed at the determination of the addition of the reclaimed material, obtained in the dry mechanical reclamation, on properties of the moulding sand with the Geopol 618 binder, which is water-glass modified by polymers and hardened by esters.
New Possibilities of Shaping the Surface Properties in Austempered Ductile Iron Castings
Authors: Myszka D.
Published: April 2013

The paper presents recent developments concerning the formation of surface layer in austempered ductile iron castings. It was found that the traditional methods used to change the properties of the surface layer, i.e. the effect of protective atmosphere during austenitising or shot peening, are not fully satisfactory to meet the demands of commercial applications. Therefore, new ways to shape the surface layer and the surface properties of austempered ductile iron castings are searched for, to mention only detonation spraying, carbonitriding, CVD methods, etc.
Modeling of Two-Stage Solidification: Part II Computational Verification of the Model
Authors: Wodo O. , Gawrońska E.
Published: April 2013

In Part I of this article, two-stage solidification model was presented. In this part we use our model to simulate solidification of the Al 7% Si alloy for two cooling rates -2 deg/s and -20 deg/s . Simulations have been performed for two eutectic transformation modes, typical for modified and unmodified alloys. Obtained cooling curves are qualitatively consistent with the typical cooling curves for modified and unmodified alloys. Moreover, evolution of cooling-curve characteristics is compared with the analytical model and found to be in close agreement.
Character and structural evolution of the Mała Łąka Fault in the Tatra Mts., Carpathians, Poland
Authors: Dąbrowska Magdalena , Jurewicz Edyta
Published: April 2013

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Abstract Dąbrowska, M. and Jurewicz, E. 2013. Character and structural evolution of the Mała Łąka Fault in the Tatra Mts., Carpathians, Poland. Acta Geologica Polonica, (1), 137-151. Warszawa. The Mała Łąka Fault in the Tatra Mts. is a synsedimentary normal fault responsible for the variable thickness of Eocene deposits in the area. Its main activity took place in the interval from the sedimentation of red conglomerates to the appearance of nummulitic limestones. The estimated throw is up to 350 m. Near the northern margin of the Tatra Mts., the trend of the fault changes from N-S to NE-SW. This part of the fault could have been activated during the Neogene uplift of the Tatra Mts. and rejuvenated as a sinistral fault. In the upper reach of the Mała Łąka Stream, the fault trend does not follow the course of the Mała Łąka Valley. Here, the flowing stream waters used extensional fractures within a damage zone associated with the Mała Łąka Fault rather than the lithological boundary at the tectonic contact between the Triassic dolomites and the Eocene conglomerates. The fault has a hingelike character; its hinge was located in the present-day Kościeliska Valley, c. 2.5 km west of the Mała Łąka Valley.
Changes in Organic Carbon Pool in Agricultural Soils and its Different Development in Individual Agro-Climatic Regions of Slovakia
Authors: Barančíková Gabriela , Makovníková Jarmila , Skalský Rastislav , Tarasovičová Zuzana , Nováková Martina , Halás Ján , Koco Štefan , Gutteková Monika
Published: April 2013

Soil organic carbon (SOC) is one of the basic parameters of soil productivity and quality. Generally soil has potential to sequestrate or release organic carbon depending on land use/management and climatic conditions. The main aim of this article is to show changes in SOC in agricultural land of Slovakia over almost the last 40 years on the basis of modelling data of SOC stock by the RothC model and unequal development of SOC stock on agro-climatic regions of Slovakia. The results received show that average SOC stock [t/ha] in Slovakia is higher on grasslands in comparison to arable land. However, total SOC pool (t) in top of 0.2 m of soil on the modelling area of agricultural Slovak land shows that a considerable part of SOC stock is located in arable land and is approximately four times greater than on grasslands because the arable land represents about 80% of the modelling area. In the first modelling period (1970-1994), the SOC stock gradually increased, but in the second modelling period (1995-2007) no significant changes in SOC stock on the arable land were observed. In the southwest part of Slovakia, increasing of SOC stock during all modelling periods was observed; however, in the northeast part a slight increase of SOC stock only in the first modelling period (1970-1994) was found and in the second modelling period (1995-2007) decrease of SOC accumulation was observed. The results of this statistical analysis show significant relationship between carbon input/SOC stock as independent variables and agro-climatic regions as dependent variable.
Stability of softly switched multiregional dynamic output controllers with a static antiwindup filter: A discrete-time case
Authors: Zubowicz Tomasz , Brdyś Mietek A.
Published: April 2013

This paper addresses the problem of model-based global stability analysis of discrete-time Takagi-Sugeno multiregional dynamic output controllers with static antiwindup filters. The presented analyses are reduced to the problem of a feasibility study of the Linear Matrix Inequalities (LMIs), derived based on Lyapunov stability theory. Two sets of LMIs are considered candidate derived from the classical common quadratic Lyapunov function, which may in some cases be too conservative, and a fuzzy Lyapunov function candidate, which has been proven to significantly reduce the conservatism level, although at the cost of increasing the number of LMIs. Two numerical examples illustrate the main result.
An autonomous vehicle sequencing problem at intersections: A genetic algorithm approach
Authors: Yan Fei , Dridi Mahjoub , El Moudni Abdellah
Published: April 2013

This paper addresses a vehicle sequencing problem for adjacent intersections under the framework of Autonomous Intersection Management (AIM). In the context of AIM, autonomous vehicles are considered to be independent individuals and the traffic control aims at deciding on an efficient vehicle passing sequence. Since there are considerable vehicle passing combinations, how to find an efficient vehicle passing sequence in a short time becomes a big challenge, especially for more than one intersection. In this paper, we present a technique for combining certain vehicles into some basic groups with reference to some properties discussed in our earlier works. A genetic algorithm based on these basic groups is designed to find an optimal or a near-optimal vehicle passing sequence for each intersection. Computational experiments verify that the proposed genetic algorithms can response quickly for several intersections. Simulations with continuous vehicles are carried out with application of the proposed algorithm or existing traffic control methods. The results show that the traffic condition can be significantly improved by our algorithm.
Cytogenetic Findings in Mentally Retarded Iranian Patients
Authors: Nasiri F. , Mahjoubi F. , Manouchehry F. , Razazian F. , Mortezapour F. , Rahnama M.
Published: April 2013

We conducted a cytogenetic study on 865 individuals with idiopathic mental retardation (MR) who were admitted to the Cytogenetics Department of the Iran Blood Transfusion Organisation (IBTO) Research Centre, Tehran, Iran; these were performed on blood samples using conventional staining methods. Chromosome anomalies were identified in 205 of the patients (23.6%). The majority were Down’s syndrome cases (n = 138). In 33 males, a positive fragile X anomaly was found .The remainder (n = 34) had other chromosomal abnormalities including structural chromosome aberrations (n = 23), marker chromosomes with an unknown origin (n = 3), sex chromosome aneuploidy (n = 6) and trisomy 18 (n = 2). The contribution of chromosome aberrations to the cause of MR in this group of patients is discussed.
Optimization of a Compact Model for the Compliant Humanoid Robot COMAN Using Reinforcement Learning
Authors: Colasanto Luca , Kormushev Petar , Tsagarakis Nikolaos , Caldwell Darwin G.
Published: April 2013

COMAN is a compliant humanoid robot. The introduction of passive compliance in some of its joints affects the dynamics of the whole system. Unlike traditional stiff robots, there is a deflection of the joint angle with respect to the desired one whenever an external torque is applied. Following a bottom up approach, the dynamic equations of the joints are defined first. Then, a new model which combines the inverted pendulum approach with a three-dimensional (Cartesian) compliant model at the level of the center of mass is proposed. This compact model is based on some assumptions that reduce the complexity but at the same time affect the precision. To address this problem, additional parameters are inserted in the model equation and an optimization procedure is performed using reinforcement learning. The optimized model is experimentally validated on the COMAN robot using several ZMP-based walking gaits.
Sinus – A Semantic Technology Enhanced Environment For Learning In Humanities
Authors: Agre Gennady
Published: April 2013

The paper describes a semantic technology based environment intended for developing technology enhanced learning applications in humanitarian problem domains. The environment consists of three layers: the storage layer contains heterogeneous repositories storing domain and pedagogical knowledge; the tool level contains a set of tools for processing different types of knowledge and the middleware layer is implemented as an extended search engine carrying out all necessary communications between the tools and the repositories. Some implementation issues are discussed and a preliminary evaluation of the environment based on an exploitation is presented.
Experimental Study of Lyapunov Equation Solution Bounds for Power Systems Models
Authors: Savov Svetoslav , Popchev Ivan
Published: April 2013

This research work investigates the applicability of some lower and upper, matrix and scalar bounds for the solution of the Continuous Algebraic Lyapunov Equation (CALE), when the coefficient matrices are the state matrices of real data models. The bounds are illustrated for two different models describing the dynamic behavior of power systems - a two-area power system and an interconnected power system. Some important conclusions referring to the accuracy of the respective estimates are made, as well.
Codes Correcting Limited Patterns of Random Errors Using S-K Metric
Authors: Sharma Bhu Dev , Gaur Ankita
Published: April 2013

Coding is essential in all communications and in all multi-operation devices, and errors do occur. For error control, the method in vogue is to use code words with redundant digits. The number of redundant digits is determined based on two things − the number of messages and the kind of errors that need to be controlled. For efficient coding the redundant digits have to be kept to the minimum.

In this paper we introduce the idea of limited error patters while using the code alphabet {0,1, 2,..., 1},mod , q Z = q − q when q > 3. We define limitations of the errors in a position by substitution of the character there by a specified number of other characters, rather than by any other character. This is not possible through Hamming approach, because there a character in an error could be substituted by any other of the q-1 characters. The firm mathematical base is provided by use of a metric from the class of S-K metrics, Hamming metric being one of these.

The paper gives upper bounds on the codeword lengths for various kinds of “random limited error patterns”. Examples and discussion bring out the tremendous improvement and generalization of Rao Hamming bound.
High-degree Precision Decomposition Method for an Evolution Problem
Authors: Gegechkori Z. , Rogava J. , Tsiklauri M.
Published: April 2013

In the present work, a symmetrized sequential-parallel decomposition
method of the third degree of precision for solving Cauchy abstract problem is suggested.
The third degree of precision is reached by introducing the complex coefficient
α=1/2±i/(2√3)s. For the scheme considered, explicit a priori estimation is obtained.
An Analytical Approach for Quasi-Linear Equation in Second Order
Authors: Perepelkin E.E. , Zhidkov E.P.
Published: April 2013

This paper is devoted to the studies of the properties of the solutions
of non-linear partial differential equation, being basic ones in
differential formulation of the magnetostatic problem of finding the magnetic field dis-
tribution. The question of the existence of solutions, possessing an unlimited gradient,
for this equation is of particular interest. Previous works dealt with the linear
equation type, and also a boundary value problem was con-
sidered for certain requirements for the µ function, as well as a more general non-linear
case was studied. It was shown that such solutions exist, and their properties will be
investigated. The difference scheme for the boundary value problem was built in the
domain with corner and numerical calculations were given.
Amrvac: a Multidimensional Grid-adaptive Magnetofluid Dynamics Code
Authors: Nool Margreet , Keppens Rony
Published: April 2013

We present the results obtained with AMRVAC, a software package
designed for solution-adaptive time-accurate (magneto)hydrodynamic simulations. In
any dimensionality, the grid adjusts to capture shocks and other sharp flow features
accurately following an automated Adaptive Mesh Refinement [AMR] strategy. This
grid adaptation algorithm is incorporated with the Versatile Advection Code [VAC],
so that it can be used to time-advance sets of conservation laws with options for the
spatial discretization employed. We demonstrate and evaluate the efficiency achievable
by AMR for 1D, 2D, and 3D test problems and describe the employed data structures.
Numerical Solutions of Fuzzy Differential Equations by Taylor Method
Authors: Abbasbandy Saeid , Viranloo Tofigh Allah
Published: April 2013

In this paper, numerical algorithms for solving “fuzzy ordinary differential
equations” are considered. A scheme based on the Taylor method of order p is
discussed in detail and this is followed by a complete error analysis. The algorithm is
illustrated by solving some linear and nonlinear fuzzy Cauchy problems.