bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of Empirically Derived Oil Recovery Factor Regression Equations to Water Drive Reservoirs in Niger Delta
Authors: Okpere Adrian , Charles Ndibueze
Published: July 2013

In order to make sound investment decisions with regards to oil field appraisal and development, it is crucial to be able to properly predict reservoir performance and hence oil recovery factor. Oil recovery factor is the recoverable fraction of the initial oil in place. It varies across different reservoirs depending on depositional environment, drive mechanism, rock and fluid properties.

Over the years, a variety of methods have been used for the estimation of oil recovery factors vis (Analytical, Simulation, Empirical e.t.c). The thrust of this paper will focus on the use of empirically derived recovery factor regression equation for estimating oil recovery factor for water drive reservoirs in the Niger Delta. This method was first developed by the American Institute of Petroleum (API) subcommittee on recovery efficiency in Nov., 1967 with the publication of API Bulletin D14 "A Statistical Analysis of Recovery Efficiency" The subcommittee used case histories from some 312 producing oil reservoirs with sandstone lithology from which certain empirical relationships were derived by regression analysis. Specific regression equations were developed for Water-drive and Solution gas reservoirs.

This paper presents the practicality of using the regression equation for water drive reservoirs in the Niger Delta, which have similar lithology. Firstly, a form of robustness check was done with mature reservoirs to see how well prediction from the regression equations line up with reality. Secondly, the equation was used to predict recovery efficiency in green reservoirs and results compared with other recovery factor estimation methodology noting the standard deviation in both cases. The results compared favorably and could be used as an additional robustness check when estimating reservoir recovery factor for water drive reservoirs in the Niger Delta.
Insights from the 3D Modeling of a Densely Faulted, Stacked Reservoir System
Authors: Oluseyi Ekanem , Osemoahu Omobude , Uchenna Onyemannadi , Ugochukwu Aboaja
Published: July 2013

The field presented in this paper is a structurally complex onshore oil field in the Niger Delta, with a densely faulted succession of stacked reservoirs. From previous field studies, three of the reservoir units have been interpreted as a single stacked reservoir complex beneath a top seal, and the vertical and lateral communication between these units is largely controlled by the inter-reservoir shales and intense fault configuration.

Integrated 3D reservoir modeling has been used to investigate the production performance from this stacked reservoir complex, with a view to identifying the features that contribute to the observed communication across the reservoirs, quantifying the contribution of each reservoir unit to each well's production, estimating the ultimate recovery for the complex and evaluating the current redevelopment plan for the reservoir complex to identify opportunities for further oil development.

The results from the study indicate that oil recovery is majorly influenced by communication across faults. A tracer model was used to demonstrate that some wells produce from adjacent blocks on the same reservoir unit as well as the other reservoir units across the fault, giving an indication of the presence of non-sealing faults across juxtaposed oil-bearing sands. Also the application of the 3D model in evaluating the current redevelopment plan for the reservoir complex resulted in the identification of 5 new opportunities in existing wells, to increase the ultimate recovery of the reservoir complex by 7.8MMstb. More so, there exists an opportunity to recover 7.5MMstb from a by-passed section of the complex with a new vertical well.
Reconstruction and Re-Interpretation of Pressure Transient Data from Old Well Tests Using Digitization Technique
Authors: Ikwan Ukauku , Peter Ikenebomeh , Dike Nnamdi , Chima Emelle
Published: July 2013

Pressure transient analysis is a veritable technique for reservoir characterisation offering a variety of oil and gas field development information ranging from reservoir permeability, anisotropy, boundaries to wellbore skin, well interference and productivity/injectivity to mention but a few. Well test data acquired at exploration and appraisal stages of oil and gas fields and their interpretation often times need to be re-visited at field development stage when this information are needed to underpin field development plan and reserves assessment. Changing perspective in field understanding as well as advances in well test interpretation may warrant a re-interpretation of pressure transient data from old well tests but at this stage Petroleum Engineers are faced with challenge of unavailability of test data in electronic form to re-visit interpretation with new techniques. Often times data may only exist in paper form.

In the quest to grow Africa Oil and Gas production, this paper is sharing a successful investigation of a technique for digitising pressure transient data that exist in paper form into electronic data for the purpose of reinterpreting an old test with recent advances in interpretation technique. The approach is illustrated with results from field testing of a multi-rate test data of a gas well in the Niger Delta acquired and interpreted in the early ‘90s but undergoing field development planning and resource volume evaluation two decades later.

Good results were obtained in the field trial, using the techqnique offered in this paper. The re-interpreted reconstructed pressure transient data led to permeability improvement from about 30 to 80 mD using appropriate models in consonance with advances in well test interpretation. This result has been used to update the simulation models for field development planning and reserves booking purposes for the trial field.
CFD Investigation of Application Potentials of Molybdenum Trioxide as Drilling Fluid Additive for HPHT Drilling Applications
Authors: Mohammed Auwalu Inuwa , Oluyemi Gbenga , Ibrahim Sulaiman Dodo
Published: July 2013

Rheology of drilling fluids is usually evaluated without taking wellbore pressure and temperature effects into consideration. In most instances these evaluations produce fairly accurate results for shallow wells owing to the usually very small difference between surface and subsurface bottom-hole temperatures in shallow wells. As such, the rheology of the drilling fluid does not change substantially while drilling wells of these types. However, in wellbores where bottom-hole pressures and temperatures are well above the average pressure and temperature, especially in deep and ultra-deep wells, significant changes in drilling fluid rheology may result. A classic example of this scenario is common in HPHT drilling environments. In these difficult and challenging environments pore pressure gradient could be in excess of 0.8psi/ft and bottom hole temperature (BHT) in the range of 150°C to 300°C or even greater.

Invert emulsion drilling fluids have reportedly been used to drill HPHT wells with temperature of up to 260°C with little problems or challenges. Nevertheless, recent HPHT activities have presented more difficult challenges with bottom hole temperature approaching 316°C and pore pressure in the neighbourhood of 20000 psi. These challenges have in turn presented the need to adopt a further innovative approach to drilling fluid management under this extreme condition.

This paper presents a numerical investigation of application potentials of molybdenum oxide as a rheology control additive in drilling fluids for more challenging HPHT well drilling. Simulations were carried out using Ansys Fluent CFD™ software whilst analysis and interpretation of results was carried out with the aid of Tecplot Visualisation™ Software.

The Simulations replicated the real life flow scenarios for both concentric and eccentric annuli under bottom-hole conditions of HPHT; and rotating (dynamic) and non-rotating (static) drill pipes.

Application of Molybdenum as a drilling additive for all the simulated scenarios resulted in improved effective drilling mud viscosity, supporting the conceptual propposition that molybdenum oxide can serve as a good additive for drilling fluid rheology control and maintenance in HPHT environments.
Environmental Remediation of Oil Spillage in Niger Delta Region
Authors: David Olayinka E. , Joel Ogbonna F.
Published: July 2013

The impacts of oil spills are not limited to the direct effect on the ecosystem; it goes a long way to affect the social welfare, aggravates poverty, population displacement, social conflict, production reduction and also affects the profit margin of the companies involved. This study is aimed at providing a review and comparison of the remediation techniques currently in use and suggest the most suitable methods of oil spill cleanup and remediation in Nigeria Niger Delta region based on certain criteria and to also suggest ways of mitigating oil spill occurrences in this region. In the course of this research study, data collection was on primary and secondary data. For the primary data, a structured questionnaire was drafted and used for survey relating to the research study to rank and evaluate different perspectives of stakeholders on various remediation techniques that are in consideration. For the Secondary Data, the study was carried out with a literature study to gain an overview of the different remediation methods for PHCs contaminated soils.

Finally using specific criteria including cost efficiency, operation and maintenance of the technique, environmental friendliness, time frame of achieving remedial objectives, health concerns, and applicability of the techniques were used to make an evaluation design for the different remediation techniques for hydrocarbons contaminated soils.

The results from these studies show that single remedial action cannot be used for cleanup but the Thermal desorption and Remediation by Enhanced Natural Attenuation (RENA) was the best placed technique ranking highest under the different criteria of the evaluation design and the sample survey of the remediation techniques considered. More so, In-situ Vitrification is the most cost effective techniques with little or no disturbance of site.
Global Trend in Natural Gas Development and the Impact on the Nigerian Gas Market
Authors: Aimikhe V. J , Kinigoma B. S , Iyagba E. T
Published: July 2013

This paper takes a proper look at the current trend in Global gas development worldwide and the impact on the Nigerian Gas market. With the global gas demand set to rise above 50% between 2010 and 2035, reaching 25% of the world's energy mix, overtaking coal to become the second largest primary energy source after oil, it becomes highly imperative for gas producers to fully understand the dynamics of this growth trend. The boom in unconventional gas development in some countries of the world especially the United States who is currently a major destination of the Nigerian gas, is expected to become a net exporter by the year 2016, resulting in revenue loss from gas sales in Nigeria. The increased expansion of LNG facilities and hence production capacity in major gas producers like Australia and Qatar while growth in Nigeria has remained stagnant will affect the country's revenue from gas in the nearest future. Also, the new discoveries of large gas reserves in some countries in East Africa including Mozambique and Tanzania located in the Indian Ocean will reduce operating cost of LNG buyers in Asia when these two Nations's LNG projects come on stream in 2018, as compared to buying from Nigeria.

This paper therefore takes a look at how these trends affect the Nigerian gas Market and suggests possible ways of avoiding revenue loss from gas sales in the nearest future.
Sidetrack/Recompletion Time Evaluation by Proxy Model
Authors: Ajibola J. T. , Orodu O. D. , Onyeukwu C. A.
Published: July 2013

Sidetrack during field development and ongoing production arises to exploit bypassed reserves (unswept areas under secondary and/or tertiary recovery), unexploited zones and unforeseen conditions likely to build due to uncertainties and heterogeneity in initially characterizing a reservoir. Whereas recompletion is prone due to sequential production of stacked reservoirs or multiple pay zones that is necessitated by regulation on comingling. The purpose of this paper is to optimize the time for sidetrack/recompletion job in multiple pay zones in view of maximizing returns on investment. A simple case to elicit the workflow is based on two pay zones and applies Experimental Design (ED), and economic analysis in the form of Net Present Value (NPV).

The procedure followed for this study started with the identification of the reservoir uncertainties and their ranges; focusing basically on net pay thickness, porosity, permeability, and time to perform the sidetrack; the reservoirs are assumed to be undersaturated. The Box-Behnken response surface design in ED was used to reduce the number runs to make by generating the most effective combination of variables for the experiment. Experimental runs were conducted with a Black Oil reservoir simulator to give production profile. NPV values using stipulated Oil price, CAPEX, OPEX, tax rate, royalty and production rates were estimated, which was used afterwards to produce the Proxy model in ED and this developed correlation was used to analyse the effect of time changes. NPV computed from the Proxy Model was reasonable; however, a higher level D-Optimal design as against the 2-level design used in this study may be required for a reasonable match of NPV with respect to sidetrack (recompletion) time.

In conclusion, the incorporation of time was successful and gives way to studying the impact of not only reservoir uncertainties but the uncertainty that arises from a success or failure of the sidetrack that further gives way to the application of decision analysis and the evaluation of NPV by Proxy Models for each possible outcome.
Milling on Electric Line-Conveyed Technology in West Africa
Authors: Dulie Almir
Published: July 2013

A new application of electric wireline (e-line) tractors in combination with well milling technology has been successfully proven in two wells in West Africa.

In July of 2011 on an offshore platform, a downhole tractor in conjunction with a milling tool were conveyed on e-line to remove an obstruction created by Lost in Hole (LIH) electric wireline cable at 9,500ft (2,896m).

In total, 13 successful milling runs were made. During this unique operation most of the milled wireline material was recovered, and the challenges of controlling rate and milling penetration were overcome. In between milling runs, slickline fishing attempts were made to recover the remaining LIH wireline. After the last milling run, a major breakthrough was made as fishing operations were successful in retrieving sufficient wireline to reach the target depth.

In another case, this time in a subsea well, a flapper valve used to set a production packer needed to be opened, but despite multiple pressure cycles down the tubing, the valve remained closed. The operator had the option to pump in acid to disintegrate the valve, but due to the estimated volume of acid required, the operator wanted a different solution.

The milling tool was fitted with a tungsten carbide milling bit specially designed to mill the aluminum flapper valve. The milling bit was designed with a spring-loaded skirt that kept the valve closed while the bit was exposed. This prevented the flapper valve from opening when pulling the bit backwards. After approximately 20 minutes of milling time, the valve was milled out. The operator saved at least one day of operation.

Additionally, due to their lightweight nature, e-line tools offer HSE benefits and logistical advantages. This paper describes the process from decision-making to completion of these milling operations.
Coverage and Representation of Condoms in Conjunction with HIV/AIDS in the Kenyan Daily Nation Newspaper from 1989–2003: A Qualitative Content Analysis to Inform Health Promotion
Authors: McMorrow Shannon L. , Lagerwey Mary D. , Ford Leigh A.
Published: July 2013

HIV/AIDS has been a pressing problem in the East African country of Kenya for over 20 years. Promotion of condom use is one prevention strategy embraced in global health prevention of HIV, but use remains relatively low in Kenya. In order to better understand the socio-historic context of discourses about condoms in Kenya, this study explored how condoms were covered and represented in the Kenyan Daily Nation newspaper from 1989–2003. Qualitative content analysis was conducted for 91 items from the Daily Nation including articles, letters to the editor, columns, opinion and editorial pieces, advertisements, and cartoons. These items were systematically examined for the manner and content of manifest and latent references to condoms. Researchers found four major themes, “controversy and confusion,” “we need to do more: condoms might help,” “not for Kenyans or from Kenyans,” and “stigmatized associations.” Findings provide needed insight into the socio-cultural context surrounding condoms in Kenya that is often lacking within health promotion and HIV prevention programs.
Front-Line Worker Engagement: Greening Health Care, Improving Worker and Patient Health, and Building Better Jobs
Authors: Chenven Laura , Copeland Danielle
Published: July 2013

Frontline workers have a great deal to contribute to improving environmental sustainability of their employers and the health of workers and patients. This article discusses a national project of the Healthcare Career Advancement Program, funded by the U.S. Department of Labor to support green jobs development. Implementation was accomplished through a labor/management collaboration between union locals and 11 employers in four regions throughout the United States. The project developed and implemented a model of training and education for environmental service workers and other frontline health-care workers in hospital settings that supported systems change and built new roles for these workers. It empowered them to contribute to triple bottom line outcomes in support of People (patients, workers, the community), Planet (environmental sustainability and a lower carbon footprint), and Profit (cost savings for the institutions). In the process workers more clearly articulated their important role as a part of the healthcare team and learned how they could contribute to improved patient and worker health and safety.
Immunosuppression - postpartum diseases of dairy cows
Authors: Joksimovic-Todorovic M. , Davidovic V.
Published: July 2013

Periparturient period in dairy cows is accompanied by numerous physiological,
metabolic and nutritive changes. The way in which they occur and develop have
a great influence on lactation performances, subclinical and clinical
postparturient diseases and reproductive disorders, thus affecting the
profitability as well. During periparturient period dairy cows may subject to
the immune system function disorders. This immunosuppression leads to
increased number of severe cases of infections (mastitis, metritis, retained
placenta and other health disorders). The cause of periparturient
immunosuppression is unknown, although it is a subject of numerous studies
which suggest that immune disfunction may be provoked by both metabolic and
endocrine factors. Numerous authors suggest that negative energy balance,
non-esterified fatty acids (NEFA), ketone bodies and hypocalcaemia play a
significant role in the development of immunosuppression. It is well known
that glucocorticoids exert an immunosuppressive action. The changes in the
levels of estradiol and progesterone may have either a direct or indirect
influence on immune defence. However, their effect on the development of this
immunofunction is not long, since the changes in their concentrations are
short-lasting. Some nutrients are involved in the function of immune cells
thus minimizing the inflammatory damages, due to more efficient immune
response. Numerous tissue damages during the infection are possible, as a
consequence of oxidative stress - reaction of unstable oxidised molecules
with tissue lipids, proteins and DNA. A great number of antioxidants are
important for animal health, however, optimal concentrations and forms of
these supplements for maximizing the immune function and tissue protection
are still unknown.
Method of the Moulding Sands Binding Power Assessment in Two-Layer Moulds Systems / Metoda oceny wielkości siły wiązania mas w układzie form dwuwarstwowych
Authors: Holtzer M. , Drożyński D. , Bobrowski A. , Makselon J.
Published: July 2013

More and more foundry plants applying moulding sands with water-glass or its substitutes for obtaining the high-quality casting surface at the smallest costs, consider the possibility of implementing two-layer moulds, in which e.g. the facing sand is a sand with an organic binder (no-bake type) and the backing sand is a sand with inorganic binder. Both kinds of sands must have the same chemical reaction. The most often applied system is the moulding sand on the water-glass or geopolymer bases - as the backing sand and the moulding sand from the group of self-hardening sands with a resol resin - as the facing sand. Investigations were performed for the system: moulding sand with inorganic GEOPOL binder or moulding sand with water glass (as a backing sand) and moulding sand, no-bake type, with a resol resin originated from various producers: Rezolit AM, Estrofen, Avenol NB 700 (as a facing sand). The LUZ apparatus, produced by Multiserw Morek, was adapted for investigations. A special partition with cuts was mounted in the attachment for making test specimens for measuring the tensile strength. This partition allowed a simultaneous compaction of two kinds of moulding sands. After 24 hours of hardening the highest values were obtained for the system: Geopol binder - Avenol resin.
Determination of Heat Accumulation Coefficient for Oil Bonded Moulding Sands
Authors: Łągiewka M. , Konopka Z. , Zyska A. , Nadolski M.
Published: July 2013

The possibility of controlling the solidification and cooling time of castings creates prospects of improving their structure and by the same their properties. Thermal properties of the mould constitute therefore an important factor which is necessary to consider while seeking for the mentioned improvement. The presented work illustrates the method of determining some basic thermal coefficients of moulding material, i.e. the coefficient of temperature equalisation a2, known also as the temperature diffusivity, and the heat accumulation coefficient b2, which characterises the ability of moulding material to draw away the heat from a casting. The method consists in experimental determining the temperature field within the mould during the processes of pouring, solidification and cooling of the casting. The performed measurements allow for convenient and exact calculations of the sought-after coefficients. Examinations were performed for the oil bonded moulding sand of trade name OBB SAND ‘E’. The experiment showed that the obtained value of b2 coefficient differs from the value calculated on the basis of theoretical considerations available in publications. Therefore it can be stated that theoretical calculations of the heat accumulation coefficient are thus far not sufficient and not quite reliable, so that these calculations should be verified experimentally.
The Influence of Casting Defects on Fatigue Resistance of Elektron 21 Magnesium Alloy
Authors: Pikos I. , Kiełbus A. , Adamiec J.
Published: July 2013

The Mg-RE alloys are attractive, constructional materials, especially for aircraft and automotive industry, thanks to combination of low density, good mechanical properties, also at elevated temperature, and good castability and machinability. Present paper contains results of fatigue resistance test carried out on Elektron 21 magnesium alloy, followed by microstructural and fractographical investigation of material after test. The as-cast material has been heat treated according to two different procedures. The fatigue resistance test has been conducted with 106 cycles of uniaxial, sine wave form stress between 9 MPa and 90 MPa. Fractures of specimens, which ruptured during the test, have been investigated with scanning electron microscope. The microstructure of specimens has been investigated with light microscopy. Detrimental effect of casting defects, as inclusions and porosity, on fatigue resistance has been proved. Also the influence of heat treatment's parameters has been described.
New Investigation Method of the Permeability of Ceramic Moulds Applied in the Investment Casting Technology / Nowa metoda oceny przepuszczalności form ceramicznych stosowanych w technologii wytapianych modeli
Authors: Zych J. , Kolczyk J. , Snopkiewicz T.
Published: July 2013

The new investigation method of a permeability of ceramic moulds applied in the investment casting technology, is presented in the paper. Some concepts of performing permeability measurements are shown. Investigations in which the influence of the solid phase fraction in the liquid ceramic moulding sand (LCMS) on a permeability of a multi-layer ceramic mould were performed and discussed. The permeability was estimated during two the most important stages of the technological process: in the first - after wax melting and in the second - after mould annealing. Also an influence of the matrix grain sizes (material for sprinkling) on a ceramic mould permeability was estimated.
Optimization of Squeeze Parameters and Modification of AlSi7Mg Alloy
Authors: Zyska A. , Konopka Z. , Łągiewka M. , Nadolski M.
Published: July 2013

The paper present the examination results concerning mechanical properties of castings made of AlSi7MG alloy in correlation both with the most significant squeeze casting parameters and with the modification treatment. Experiments were planned and held according to the 23 factorial design. The regression equations describing the influence of the squeeze pressure, the mould temperature, and the quantity of strontium modifier on the strength and elongation of the examined alloy were obtained. It was found that the main factor controlling the strength increase is the squeeze pressure, while the plasticity (A5) of the alloy is affected most advantageously by modification. The application of modification treatment in squeeze casting technology enables for production of the slab-type castings made of AlSi7Mg alloy exhibiting strength at the level of 230 MPa and elongation exceeding 14%.
Screening for antiradical efficiency of 21 semi-synthetic derivatives of quercetin in a DPPH assay
Authors: Milackova Ivana , Kovacikova Lucia , Veverka Miroslav , Gallovic Ján , Stefek Milan
Published: July 2013

The group of 21 novel semi-synthetic derivatives of quercetin was screened for the antiradical efficiency in a DPPH assay. The initial fast absorbance decrease of DPPH, corresponding to the transfer of the most labile H atoms, was followed by a much slower absorbance decline representing the residual antiradical activity of the antioxidant degradation products. Initial velocity of DPPH decolorization determined for the first 75-s interval was used as a marker of the antiradical activity. Application of the kinetic parameter allowed good discrimination between the polyphenolic compounds studied. The most efficient chloronaphthoquinone derivative (compound Ia) was characterized by antiradical activity higher than that of quercetin and comparable with that of trolox. Under the experimental conditions used, one molecule of Ia was found to quench 2.6±0.1 DPPH radicals.
Evolving Non-Dominated Parameter Sets for Computational Models from Multiple Experiments
Authors: Lane Peter C. R. , Gobet Fernand
Published: July 2013

Creating robust, reproducible and optimal computational models is a key challenge for theorists in many sciences. Psychology and cognitive science face particular challenges as large amounts of data are collected and many models are not amenable to analytical techniques for calculating parameter sets. Particular problems are to locate the full range of acceptable model parameters for a given dataset, and to confirm the consistency of model parameters across different datasets. Resolving these problems will provide a better understanding of the behaviour of computational models, and so support the development of general and robust models. In this article, we address these problems using evolutionary algorithms to develop parameters for computational models against multiple sets of experimental data; in particular, we propose the ‘speciated non-dominated sorting genetic algorithm’ for evolving models in several theories. We discuss the problem of developing a model of categorisation using twenty-nine sets of data and models drawn from four different theories. We find that the evolutionary algorithms generate high quality models, adapted to provide a good fit to all available data.
Conceptual Commitments of the LIDA Model of Cognition
Authors: Franklin Stan , Strain Steve , McCall Ryan , Baars Bernard
Published: July 2013

Significant debate on fundamental issues remains in the subfields of cognitive science, including perception, memory, attention, action selection, learning, and others. Psychology, neuroscience, and artificial intelligence each contribute alternative and sometimes conflicting perspectives on the supervening problem of artificial general intelligence (AGI). Current efforts toward a broad-based, systems-level model of minds cannot await theoretical convergence in each of the relevant subfields. Such work therefore requires the formulation of tentative hypotheses, based on current knowledge, that serve to connect cognitive functions into a theoretical framework for the study of the mind. We term such hypotheses “conceptual commitments” and describe the hypotheses underlying one such model, the Learning Intelligent Distribution Agent (LIDA) Model. Our intention is to initiate a discussion among AGI researchers about which conceptual commitments are essential, or particularly useful, toward creating AGI agents.
The Control of Codling Moth (Cydia Pomonella L.) Population Using Mating Disruption Method
Authors: Płuciennik Zofia
Published: July 2013

The series of experiments on codling moth (Cydia pomonella L.) control using mating disruption method were conducted in three experimental orchards during 2006-2010 growing seasons. The efficacy of two commercial pheromone preparations: Ecodian CP and Isomate CTT, in comparison to pesticides Calypso 480 SC and Appeal 04 PA, was evaluated on the base of percentage of damaged fruits, number of caterpillars collected during their migration for overwintering in bands of corrugated cardboard placed on tree trunk and number of moths caught in pheromone traps. Two thousands dispensers of Ecodian CP were used twice a season (at 6-week interval) on the area of 1 ha of the orchard. Five hundred of Isomate CTT dispensers were applied once a season on 1 ha of the orchard. In all the experiments, application of mating disruption method significantly reduced the level of apple damage; the control efficacy (calculated according to Abbott’s formula) ranged from 54.2% to 95.8%. The efficacy of chemical control ranged from 58.5% to 93.0%. The lower efficacy of mating disruption method was noticed in orchards with high codling moth population. The treatments also affected the number of caterpillars caught in bands of corrugated cardboard placed on tree trunk. In experiments where the codling moth was not controlled, the number of caterpillars per a band varied from 0.2 to 11.9 whereas in these where the pest was controlled chemically or by mating disruption method, their number varied from 1.4 to 2.8 specimens.
The Characteristics of Fruits Morphology, Chemical Composition and Colour Changes in Must During Maceration of Three Grapevine Cultivars
Authors: Ochmian Ireneusz , Angelov Ludmil , Chełpiński Piotr , Stalev Bojan , Rozwarski Rafał , Dobrowolska Agnieszka
Published: July 2013

The study compares morphology of clusters and fruits, the chemical composition and changes of pulp in the process of maceration of grape cultivars ‘Mavrud’, ‘Pinot Noir’ and ‘Merlot’. The cultivar ‘Mavrud’ had biggest clusters and fruits. Its fruits were less firm but had the highest acidity while the fruits of the ‘Pinot Noir’ had the highest content of soluble solids and dry matter and the greatest firmness but the lowest acidity and content of nitrites and nitrates. The fruits of the ‘Merlot’ cultivar had the highest content of L-ascorbic acid, nitrites and nitrates. The pulp colour was largely affected by the maceration temperature. During a warm maceration, the process of pulp darkening accelerated and the red colour saturation increased, whereas cold maceration resulted in the blue colour saturation.
Zeolite as Material for Hydrogen Storage in Transport Applications / CEOLĪTA KĀ ŪDEŅRAŽA UZGLABĀŠANAS VIDES IZPĒTE
Authors: Kleperis J. , Lesnicenoks P. , Grinberga L. , Chikvaidze G. , Klavins J.
Published: July 2013

For transport needs the hydrogen is mostly stored in a compressed (at 350-700 bars) form, while methods for its storage at lower pressures are rapidly developing. In particular, nanoporous oxides and zeolites, which do not normally absorb notable amount of hydrogen, with a small Pd additive or ion exchange demonstrate enhanced hydrogen adsorption properties. An original thermogravimetric method has been developed to study the hydrogen adsorption in zeolite, consisting of its heating in the inert gas (argon, nitrogen) flow and cooling in the hydrogen atmosphere. It is found that natural zeolite (clinoptilolite) with Mg-ion exchange possesses a high adsorption capacity for hydrogen - up to 6.2 wt%, which is explained by its encapsulation in zeolite pores. The FTIR spectra of the hydrogen-treated samples have shown new absorption bands at 2340 and 2360 cm-1.
Urban Shrinkage as a Challenge to Local Development Planning in Slovakia
Authors: Buček Ján , Bleha Branislav
Published: July 2013

The demographic characteristics of "shrinking" processes in large Slovak cities, as well as the awareness of such shrinkage processes in local development planning, is the subject of this article. Population loss, together with other demographic indicators, clearly documents such a trajectory in urban development. In spite of this reality, there is only limited reflection of the "shrinking" in planning documents of cities approved by town councils. Some reasons for this decreased sensitivity to the complex problem of shrinking cities include missing relevant information (e.g. demographic prognoses), the milder forms of "shrinking" in Slovakia, the absence of political acceptance of the process by local elites, and the dominant-growth oriented planning practices.
A Dynamic Approach to the Typology of Functional Derelict Areas (Sosnowiec, Poland)
Authors: Krzysztofik Robert , Kantor-Pietraga Iwona , Spórna Tomasz
Published: July 2013

The increasing number of wastelands in East-central European countries is primarily a consequence of functional transformations and movements in the structure of employment. Taking into account such a challenge in this article, the authors propose an approach in which the basic category is a typological proposal with reference to areas with derelict functions, which in turn refers to research within the scope of human geography. In their methodological proposal, the authors consider such variables as: (i) the diversification of management and use of space; (ii) time; (iii) economic functions; and (iv) the scope of geographic research. The effect of including these variables is an attempt to dynamically depict the evolution of land use, with particular attention paid to wasteland: original state - transitional state (derelict areas) - present state. The typological depiction of the emergence and transformation of areas with derelict functions is presented for the case of Sosnowiec.
The Spatial Pattern of Brownfields and Characteristics of Redeveloped Sites in the Ostrava Metropolitan Area (Czech Republic)
Authors: Novosák Jiří , Hájek Oldřich , Nekolová Jana , Bednář Pavel
Published: July 2013

Differences between brownfields and redeveloped sites in the Ostrava metropolitan area are subject to analysis in this paper. Environmental burden and former functional use were identified as statistically significant characteristics of such differences. In addition, relations between selected attributes of brownfields and redeveloped sites were analyzed using the “if-then” decision rules of the rough set method. In this way, the research demonstrated the significance of spatial aspects and identified two fundamental types of brownfields in the model area. The first type is represented by agricultural brownfields in the hinterland zone, that are characterized by a complicated ownership structure. Brownfields of the second type are located particularly in the inner city morphogenetic zone, and are characterized by potential problems with environmental burden. In this context, brownfields and redeveloped sites differ respectively in the combination of these characteristics.
Various Aspects of the Genesis and Perspectives on Agricultural Brownfields in the Czech Republic
Authors: Skála Jan , Vácha Radim , Čechmánková Jarmila , Horváthová Viera
Published: July 2013

Abandoned agricultural objects from the period of large-scale agricultural production in the socialist era represent a peculiar topic in the former communist countries of Eastern Europe, surpassing the experience of the EU15 countries or USA that have extensive and long-standing practice in brownfields redevelopment. The question of brownfields resulting from the transformation of the agricultural sector during the transition period of the Czech Republic is presented in this paper. Agricultural brownfields are the most frequently occurring brownfields in the Czech Republic (especially in some regions), but their area share is much lower, indicating their spatial disposition in the landscape. Some aspects of agricultural brownfields regeneration, including possibilities of its funding, are discussed in the paper. We also deal with geographical, environmental and historical aspects of the existence of these localities in the Czech Republic in the context of potential financial resources and possibilities for funding their revitalization.
Rebranding Development Communications in Emergent India
Authors: Chakravartty Paula
Published: July 2013

With access to and competence in new ICTs a defining feature of modern citizenship in much of the global South, we need to understand the complex and ambivalent discourse around public-private partnerships, digital inclusion and the very rebranding of development communication in the 21st century. India’s prominence in this area is partially explained by the economic and symbolic success of its export-oriented IT industry. The spectacular nature of economic disparities in the world’s largest democracy - an emerging market vying for global recognition with some of the most severe rural poverty rates worldwide - has meant that private sector actors are increasingly eager to present themselves as active participants in a new discourse of development. In unequal information societies across the global South like India, a critical analysis of corporate actors in the development arena must take into account the wider field of conflict and struggle over the redistribution of public resources evident in the era of liberalization.
Communication for Development in Good and Difficult Times
Authors: Balit Silvia
Published: July 2013

The article tells the story of the evolution of communication for development within the United Nation’s (UN) Food and Agriculture Organisation (FAO), describing the good times in the past as well as the difficult times in the last decade as an example of how the discipline continues to be marginalised in development institutions. The author argues that new challenges and trends demand new thinking on the part of institutions and governments, as well as new practices and skills by communication practitioners, and stresses the need to avoid re-inventing the wheel. New approaches should be married up with the participatory principles and methodologies applied in the past that are still valid for meeting the new challenges. The article concludes with a discussion of the prerequisites for an enabling environment for mainstreaming communication for development.
The Globalization of the Pavement
Authors: Ekström Ylva , Hansen Anders Høg , Boothby Hugo
Published: July 2013

This article investigates examples of citizen media production and communication (blogs and social media sites in Tanzania and its diasporas) in the immediate aftermath of the Gongo la Mboto blasts in Dar es Salaam, Tanzania, February 2011.

At the centre is the relationship between media use and communication practices of the pavement - drawing from the notion of pavement radio - and the spaceship, i.e. a metaphor for traditional mass media, exemplified by policies and practices of the BBC and its World Service.

We argue that new social media practices as digital pavement radio are converging with traditional forms of street buzz and media use. Forms of oral communication are adapting towards the digital and filling information voids in an informal economy of news and stories in which media practices are stimulated by already ingrained traditions. An existing oral culture is paving the way for a globalization of the pavement.
Social Entrepreneurship and Communication for Development and Social Change
Authors: McAnany Emile G.
Published: July 2013

This article argues that social entrepreneurship has not yet been adequately defined even though it is increasingly being used in social change/development practice. Muhammad Yunus, creator of the Grameen Bank and microlending, and Bill Drayton, founder of the global change agency Ashoka, have practiced social change through social entrepreneurship for more than 30 years. Increasingly, the development community has been adopting many of its practices. The basic process of social entrepreneurship involves: defining a social goal for the solution of a serious problem; innovation in solving the problem; ability to expand the organization to serve large numbers of people (scaling up); focusing on the social bottom line with empirical evidence (impact evaluation). Three cases are briefly reviewed to illustrate this process. Finally the article examines how these practices might help Communication for Development (C4D) to better adapt its own practices in achieving real change with people.
“Nobody has 257 Friends”
Authors: Linaa Jensen Jakob , Scott Sørensen Anne
Published: July 2013

In the present article, we discuss norms of friendship and privacy on social network sites by examining strategies of privacy among users, arguing that tacit norms of friendship are now more easily observed. The article is based on a quantitative survey among 1710 Internet users in Denmark, among them 970 Facebook users, subsequent focus group meetings with 20 respondents and finally access to their profiles for a period of twelve months. In line with the research literature on social network sites, our study shows that users’ “friends” consist of a variety of strong, weak and even latent ties and thus supports notions such as social divergence and networked publics, suggested by danah boyd. Regarding privacy issues, we distinguish between level of access to information on participants’ profiles and the way participants perform on their profiles, the level of intimacy. As to the first level most respondents seem to emphasize whom they friend, while they do not distinguish among friends once they are in; everybody is treated equally. As to the second level, our research deviates from findings suggesting that in particular young people are rather unaware of risks, as we can identify what we call a “cautious sensible” strategy in all age groups that allows users to be cautious without being too self-restrictive. Regarding the status updates, we identify a schism between saying and doing, as our respondents tend to downgrade small talk in the focus groups, whereas their profiles reveal that they in fact do engage in small talk. We understand this seeming paradox in a generic and linguistic perspective, using the notions of phatic and indexical communication, respectively, in an analysis of the status updates on the profiles.
Quench dynamics in spin crossover induced by high pressure
Authors: Nesterov Alexander , Ovchinnikov Sergey , Iaroshenko Grigorii
Published: July 2013

In this paper we have analytically and numerically studied the dynamics of spin crossover induced by time-dependent pressure. We show that quasi static pressure, with a slow dependence on time, yields a spin crossover leading to transition from the high spin (HS) quantum system state to the low spin (LS) state. However, quench dynamics under shockwave load are more complicated. The final state of the system depends on the amplitude and pulse velocity, resulting in the mixture of the HS and LS states.
Preliminary environmental historical results to reconstruct prehistoric human-environmental interactions in Eastern Hungary
Authors: Salisbury Roderick , Bácsmegi Gábor , Sümegi Pál
Published: July 2013

Palaeoenvironmental research is playing an important role in recent archaeological investigations. We present preliminary results of geoarchaeological analyses conducted at a palaeochannel located between two prehistoric archaeological sites in eastern Hungary. The study area lies within the Körös River Basin in Békés County, a region of intensive human occupation beginning in the Neolithic, ca. 7550 BP, and represents only the second palynological analysis done in conjunction with archaeological investigations and adjacent to an archaeological site in the Körös region. Pollen from an environmental monolith was used to reconstruct the local vegetation composition and the human impact on arboreal and non-arboreal vegetation near the archaeological sites. Sediment analyses helped to reconstruct hydrological activity and human impact on the local palaeochannel. Results indicate that activity from the Neolithic onwards played an important role in local environmental change, including increasing sedimentation and deposition of organic matter in the local waterway, some forest clearance and a shift from primarily arboreal vegetation to more grasses on elevated surfaces. The trophic status of the local channel changed several times during the Holocene. In addition, indications that groundwater levels may have been fluctuating during the period of human occupation, when combined with the other changes in the area, provide a possible partial explanation for changing settlement patterns.