bluuebunny/crossref_metadata_2025 huggingface dataset:
The Impact of Aphasia on Textual Coherence
Authors: Korpijaakko-Huuhka Anna-Maija , Lind Marianne
Published: June 2012

Difficulties in the use of lexico-grammatical resources of one's language may affect the interpretation of texts produced by speakers with aphasia as coherent. Our aim is to explore similarities and potential differences in how the textual coherence is realized by speakers with aphasia in comparison with speakers without aphasia in Finnish and Norwegian. We investigate the thematic flow and the event flow in the texts, by examining reference chains and the use of verbs, respectively, and the use of connectors that link the clauses of the text together. Differences in text production based on the presence or absence of aphasia were found in our data, but no clear cross-linguistic differences. Lexico-grammatical difficulties associated with aphasia lead to missing information about who the characters in the text are, and what types of events they are involved in. Vague or ambiguous forms of reference are also present to a larger extent in the texts by the speakers with aphasia, causing problems for the interpretation of the texts as coherent entities.
Reflexive Expressions as Discourse Strategies in Teachers’ Talk to Children with Developmental Language Disorders in Language-based Kindergartens
Authors: Yifat Rachel , Zadunaisky-Ehrlich Sara , Uziel-Karl Sigal , Banai Karen
Published: June 2012

The purpose of this study is to examine teachers’ reflexive expressions (REs) referring to what has been said or about to be said by the child, and directed at Typically Developing (TD) preschool and kindergarten children and at children with Developmental Language Disorders (DLD) who attend language-based kindergartens. Specific aims included (a) identifying the use of REs in teachers’ talk during circle-time meetings (in language-based kindergartens, and regular preschool or kindergarten); (b) characterizing the REs based on their form and function; and (c) identifying the similarities and differences between REs directed toward TD children and those directed toward children with DLD. Thirty-one circle-time sessions were recorded: ten at preschools for TD children, ten at kindergartens for TD children, and 11 at language-based kindergartens. Verbal interactions were transcribed and analyzed, using the Child Language Data Exchange System (CHILDES), and coded for categories of REs. Six major categories of REs were identified, with some categories emerging more frequently than others. Two categories differentiated teachers’ talk to TD children from those directed to children with DLD – metalinguistic expressions and requests for reported speech. These findings highlight the idea that in order to meet children's needs, teachers should be aware of the important role that interactional strategies play in scaffolding language development. Analyzing REs provides an opportunity to reflect on teachers’ instructive assumptions about how to support linguistic and conversational skills of children with DLD.
Nitrogen Injection Application for Oil Recovery in Trinidad
Authors: Sinanan B. , Budri M.
Published: June 2012

Improved oil recovery (IOR) has been attracting renewed interest amongst many operators in Trinidad in recent times. High oil prices and government incentives have increased number of studies and pilot projects in secondary and tertiary recovery processes. Whilst IOR selection is driven by rock and fluid conditions, historically most operators still gave preference to infill and outstep drilling campaigns for that last hope of primary oil. Reviews conducted on Trinidad’s past projects indicated mixed economic success of IOR projects with thermal flood projects being most successful.

Nitrogen injection has never been extensively analyzed or implemented in Trinidad and now more than before is the most opportune period to establish its place amongst the other injection mediums. This paper reviews the history and use of nitrogen injection around the globe, focuses on application to Trinidad’s fields and analyses the reservoir/geologic parameter impact on recovery through reservoir simulation. Numerical simulation was performed on blocks within an onshore mature field and recovery results showed promising project potential. Simulation was also carried out on synthetic models which mimicked the various structural dips and porosity-permeability relationships that Trinidad’s southern onshore acreage posses. The findings herein, based on immiscible injection dynamics, explains the mechanism of nitrogen injection for Trinidad’s shallow onshore reservoirs.

The overall results suggest that nitrogen injection is a real alternative and much more practical and economic than previously envisioned by investors. The technology of modern day reservoir simulation has made analysis fast and efficient using structural, stratigraphic and reservoir properties that reflects the subsurface in Trinidad. The encouraging results of this study means nitrogen injection for enhancing oil recovery can now be seriously considered by mature acreage operators who wish to lengthen the economic life span of their fields.
Evaluating a Depleted Oil and Gas Field in the East Coast of Trinidad for Disposal of Carbon Dioxide
Authors: Jaggernauth D. J.
Published: June 2012

Since the following conventions (Rio Convention, Kyoto Convention and South Africa Convention) took place, concerns have been raised about the emission of carbon dioxide gas into the atmosphere by several industrial countries. Currently a few companies at the Point Lisas Industrial Complex, West Trinidad (see Figure 3), produce about 120 million standard cubic feet per day (mmscfd) of CO2 in the form of waste gas. Despite the gas being so readily available and at a relatively cheap price (< US $ 0.25/mscf) there is no reason for the current disposal practice (by venting the gas to the atmosphere), to be allowed to prevail. The carbon dioxide, which is vented, comprises 99.4% pure gas at 117 °F and requires cooling and drying before any compression can take place. Several depleted reservoirs in existing oil and gas fields throughout Trinidad were analyzed for disposal of the carbon dioxide. The only field that fit the criteria for good storage for the next eighty (80) years at the prevailing production rates is the Teak Field, which was previously operated by BPTT (formerly Amoco Trinidad), but is now operated by Repsol YPF (Trinidad). Since this field is located in the Atlantic Ocean, East Trinidad, even if there is a surface breakthrough it would not affect the environment. Thus the Teak Field, which is a depleted oil and gas field, offers a good disposal source for the present carbon dioxide generated at the Point Lisas Industrial Estate for the next eighty (80) years, along with the adjacent fields like the Saaman and Poui Fields offering a further forty (40) years each. The estimated cost for this project will be US $ 160 million which will include upgrading the facilities at both Point Lisas and on the Teak Platforms, and the laying of the 16" pipeline. Since this project is not revenue generating, it is only being considered for the long term adherences to the international standards for the reduction of carbon dioxide into the atmosphere.
Effect of Fracture Intensity and Longitudinal Dispersivity on Mass Transfer in Fractured Reservoirs
Authors: Haddad A. Sharifi , Hassanzadeh H. , Abedi J. , Chen Z.
Published: June 2012

Accurate modeling of fluid transport in fractured reservoirs is challenging because of their heterogeneous nature. One of the sources of heterogeneity is the fracture spacing. In this study, an analytical model which describes the effect of fracture intensity on mass transfer during an advective-dispersive process in dual porosity systems is introduced.

The mass transfer process is modeled using different distributions of the fracture network that results in a various range of matrix-fracture connectivity inside the reservoir and resembles the variable flow path for the mass transport. In this work probable fracture network distributions in the field are tested and the effect of the matrix block size distributions and longitudinal dispersivity inside the fracture network on the transport of the injected tracer in the reservoir is obtained. The model consists of an infinite acting reservoir with planar matrix blocks and a radially divergent continuous injection system. Results show that using the breakthrough time of the injected tracer, the stored mass inside the reservoir as a function of fracture intensity and the dispersivity coefficient can be estimated. Analytical solutions are provided and can be used to study the tracer transport in fractured reservoirs with variable fracture intensity.
Challenges of Al Zaafarana FPSO Main Class Renewal Without Moving to Dry Docking: Case Study
Authors: Hamdy E. , Hendy M. , Hamed K. , Hussein A.
Published: June 2012

Zaafarana Oil field is located in the north central Gulf of Suez off the coast of The Arab Republic of Egypt. The field is approximately 4 miles (6.5 km) from the coast in 189 feet (57 m) of water depth.

The field consists of offshore platform and a Floating Production, Storage and off-loading facilities (FPSO) figure (1). The FPSO is located approximately 800 m from the platform to process and export the oil. FPSO is Power supply the production platform via a sub-sea cable. Crude received to FPSO from platform via 8" oil pipe line figure (2).

According to FPSO surveyor (DNV) class and IIP (In service inspection program), Special survey 5 (5 years period) have been carried out for FPSO, the survey included hull and machinery.

After through hull survey and UTM gauging, it was found that;-Wastage and thickness diminutions vary from 5% to 28%.-Crack between two cargo tanks

The steel renewal and crack repairs are extensive, critical and risky to be done during FPSO in service, because it needs hot work, normally steel replacements are carried out at dry dock.

This paper is discussing the methodology used to avoid the work in dry dock and secure DNV class certificate and to maintain the safe condition of the ‘FPSO’ without disturbance or stopping oil production.
Race for Liquids vs Gas: How To Redesign a Depletion Strategy to Maximise Fluids Recovery in a Mature Thin-Oil Rim Reservoir
Authors: Moosai R. , Alleyne B. , Thomas S. , Smith D. , Cavaleri N. , Quinn M. Anthony
Published: June 2012

Hydrocarbon reservoir management of a mature reservoir is a complex process of deciphering the reservoir character, through dynamic static data integration, to produce an ideal depletion strategy for the field. A great result is normally a winning opportunity set or strategy defined by a marriage of maximum hydrocarbon recovery with fantastic economic indicators. Is it any wonder we invest heavily into tools and processes to achieve just this!

This paper will explore the use of structural and reservoir modeling tools and techniques to re-design an optimal depletion strategy for an oil and gas reservoir, in a predominantly gas field, in the Columbus basin off the East coast of Trinidad. This reservoir is a massive ~700 ft sand incorporating a 30~40ft thin oil rim with an underlying aquifer and overlain by a huge gas cap. Both oil and gas has been produced from this reservoir since 1998 by 8 oil wells and 4 gas wells spread across two fields.

Should the future of this reservoir first rely on targeting remaining oil or do we shift into high gas acceleration gear? To solve this conundrum all subsurface hands were brought on deck. The formulation of an appropriate depletion plan requires a multi pronged approach, as a clear alliance must be made between business objectives, reducing risk and good reservoir management practice.

A VIP/Nexus reservoir simulation model was the ‘tool of choice’ to investigate which depletion direction to forge ahead with. The first stage of this reservoir management investigation was the creation of a reliable structural model which then acted as the foundation for the build of a representative reservoir model. As part of this paper’s journey, we delve into the process flow used to mimic this magnificent reservoir. We endeavor to deepen your understanding of, the application of crucial petrophysical modeling in the reservoir characterization procedure and the unmistakable impact of history matching over 12 years of production and pressure data. The result of this work was a fit for purpose reservoir model enabling the operator to make the right decisions for future development of this reservoir.
Impact of the Future Exploration and Oil Production in the Brazilian Energy Matrix
Authors: Dias Marques J. B. , Avansi G. D. , Trevisan O. V. , Schiozer D. J.
Published: June 2012

The global energy production reflects an excessive percentage of non-renewable energy. Therefore, a great volume of investment on renewable energy became a serious matter in order to mitigate the damage caused by the consumption of energy from fossil sources. On the other hand, Brazil’s oil companies are living a decisive moment in terms of investments in energy bases, because there is a great demand for capital resources to develop the latest discoveries of enormous non-renewable supplies. In this context, this paper describes the impact of the projects announced by the oil and gas industries in the Brazilian energy matrix. The data comes from the plans presented by the major oil companies that operate in Brazil basins, mainly in pre-salt region, and from reports published by EPE (Energy Research Company – Government of Brazil).

This work involves projections from 2011 to 2020 and it was made assuming three global economic scenarios: recession, stability and economic growth. Projections are treated in a comprehensive knowledge by a simple econometric model and based on the investments announced by the oil industry of the country. Studies take into account the fossil and renewable energy projections under assumptions from the Ten Year Plan for Energy Expansion in 2020 produced by the National Council for Energy Policy (CNPE, in the Portuguese-language acronym).

The results indicate viable economic projects in the renewable energy for the Brazilian oil and gas companies (energy corporations), primarily biofuels, wind and solar power, in the expense of some oil production projects in their portfolios. Brazil is experiencing a great time to develop the renewable energy sources that is made by other countries and if these changes accelerate, it will be the potential to improve its economy by creating millions of jobs.

As main conclusion, the decisions on investment in renewable energy with capital acquired from the pre-salt projects will determine the future of the Brazilian energy matrix. The main goal of this paper is to indicate a transition to a cleaner energy matrix considering an alternative investment plan, and show some fundamental concepts to illustrate how the renewable energy can be important for the oil and gas companies’ subsistence in the next generations.
Design Considerations for Oil-Based, Squeeze Cement Slurries to Prevent Unwanted Fluid Production: Methods of Slurry Performance Evaluation and Potential Formulation Improvements
Authors: Reddy B. R. , Eoff Larry
Published: June 2012

Nonaqueous cement slurries have been used for many years to prevent unwanted water or gas production and to repair holes/cracks or other pathways that could have formed in the casing, cement column, or at the interface. Such slurries were forced or squeezed into flow channels and allowed to contact water being produced or otherwise inherently present. Exposure of cement to water presumably allows for setting of cement, thereby plugging the flow pathway. These nonaqueous cement slurries primarily contained cement, a nonaqueous fluid, and an oil-wetting surfactant. It was generally assumed that contact between cement and water allowed setting of the entire cement mass with ensuing good strength development, even though an efficient dynamic mixing of cement and water under downhole conditions is unlikely. In the laboratory, this is typically demonstrated by mixing (by means of agitation) the slurry and the required amount of water, allowing it to set at well temperatures and measuring strengths.

Laboratory mixing under quiescent conditions by addition of water to the top of nonaqueous cement slurry with no agitation, and allowing it to cure for many days, demonstrated setting of cement only at the interface as a thin solid film, while the remaining slurry was unset. It was not obvious whether the presence of set cement at the fluid interface prevented further ingress of water into the cement slurry, or if the cement particles in the bulk slurry remained too oil wet to allow hydration reactions. It was also not obvious whether a totally quiescent, totally dynamic, or an intermediate level contact between water and cement slurry truly simulated the downhole situation, accounting for the success of the technology. A surfactant combination was designed to allow deeper penetration of water into cement slurry under quiescent conditions. Details are presented.
Success in Production Estimation in High Profile Deepwater Well Using Dynamic Formation Testers
Authors: Aguilera L. E. , Flamenco F. J. , Contreras J. E. , Urbina M. R. , Fuenleal N. A. , De Nicolais N. Y. , Olivo M. A. , Miguel F.
Published: June 2012

Typically the reservoir evaluation in deep water wells (DWW) drilled by Petroleos Mexicanos (PEMEX) in southern Gulf of Mexico has been made conventionally using Drill Stem Testing (DST) operations that can take up to 23 days. This represents a significant investment in cost and time to the operator in their effort to evaluate reservoirs. The challenge was to evaluate more accurately and efficiently to reduce costs and improve reservoir characterization in these deepwater plays.

In this paper, wireline formation testers (FT) are used in openhole DWW for a variety of applications including characterization of the fluids and determination of key reservoir parameters by interval pressure transient testing (IPTT), also referred to as a mini-DST. Real-time monitoring, analysis and job optimization by senior technologists are essential steps in performing a successful logging program. Historically, the wireline programs to evaluate the zones of interest in the Tertiary approximated 8 days that included several gas zones. The new protocol brought an operational advantage to PEMEX by reducing the time required to identify and characterize zones of interest compared with conventional methods. The results included optimization of the production test programs and reduced time/costs for the well production testing stage.

The project has four major steps:

The first stage includes the identification of gas bearing sandstones and will determine the preliminary program. The highly laminated structures are evaluated with special wireline logs that include nuclear magnetic resonance (NMR), high resolution imaging and elemental capture spectrometry. After the zones are identified, the pressure profile will be analyzed with a PressureExpress (XPT) tool that is wireline combinable and allows for efficient pressure formation testing.

In the second stage, the pressure gradients are evaluated resulting in fluid types in the reservoir and mobilities for each flow unit. These results will be used to define the Mini DST stations.

The third phase involves the use of the Modular Formation Dynamics Tester (MDT) with the Live Fluid Analyzers (LFA) to characterize the fluid type in each layer. Formation fluid samples are taken according to the program’s acquisition priorities. The dual packer MDT module allows for isolating each individual layer to perform mini-DST’s that can be used to evaluate and determine the formation’s permeability and skin factor.

Finally a nodal analysis was performed using the permeability values from mini-DST. The results showed very good agreement between the rate predictions from the MDT fluid and pressure data versus the conventional DST results. This helped Pemex in strategic forecasting of production rates and reserves classification while saving rig time.
Maximizing Reservoir Exposure with Proactive Well Placement in High Geological Complexity Field of Venezuelan Orinoco Belt
Authors: Castañeda Luis , León Maryesther , Meunier Antoine , Lara Manuel , Herrera Yoanna , Granado Miguel
Published: June 2012

In 2010, Petrolera Indovenezolana S.A. (PIV), a joint venture between Corporación Venezolana del Petróleo (CVP) and the Indian company ONGC Videsh Limited (OVL), started planning for two horizontal wells in the Norte Zuata (San Cristóbal) field in the Orinoco belt of eastern Venezuela. The focus for this campaign was to evaluate the productivity of horizontal wells in thin sands and avoid areas of complex geology because of the high uncertainty in the structural behavior, applying technology that provided absolute control of the drilling process into the Oficina formation.

Within the Oficina formation, thin sand reservoirs with variations in thickness and dip, geologically facies changes and subseismic faults presented the main challenge to geosteering a horizontal well. Because the project faced high geological uncertainties, a pilot hole was drilled as the first stage in the first well to verify the structural levels and the continuity of the sand bodies.

To achieve the above challenges, the combination of a rotary steerable system (RSS) "point-the-bit" and a deep azimuthal electromagnetic resistivity tool (DAEMR) was used. The measurements provided accurate information to the well-placement engineers for proactive decisions in real time, mitigating the possible loss of the target by these geologic uncertainties.

High-quality and valuable data for real time geological model update were the expected results obtained from the effort made by PIV in the Norte Zuata (San Cristóbal) field, and the data showed the oil-producing potential of one of the main reservoir (Sand F, G). This application of high-tier technologies demonstrated that drilling and data measurements can be improved and optimized to yield added value for reservoir development and 100% net to gross (NTG) targets. This reduces operational cost, makes it possible to drill in the right place the first time, and pushes forward the limit of the achievable in terms of reservoir exposure.
3D3C Seismic Acquisition in Petrocedeño Field, Located in the Junin Area of the Orinoco Heavy Oil Belt, Venezuela. Seismic Designed for Well Implementation and Reservoir Characterization in a Fluvial-Deltaic Environment
Authors: Concepcion Monica , Sanchez Ruben , Perez Abelardo , Suniaga Jose , Vale Jesus , Cova Raul
Published: June 2012

Petrocedeño block, located in the Junin Area of the Orinoco Heavy Oil Belt, is composed of the Main and South areas, and it has been drilled by more than 660 horizontal wells in a fluvial-deltaic environment using real time monitoring, and taking into account the response of gamma ray and resistivity logs and the structure of the seismic reflectors. The Main Area is about 324 Km2 and is covered by 3D seismic acquired in 1998 with a bin size of 15 m x 15 m, a nominal fold of 20 and a vertical resolution of 15 m.

Although the two drilling campaigns has been successful, every day the challenge to identify and to drill new targets is bigger, even with the incorporation of new technologies such as azimutal resistivity tools because the sand bodies are thinner, lateral facies variations are found more often and collision problems has increased. For those matters the improvement of the pre-existing seismic data with a reprocessing in the Main Area and the design of a new seismic in the South Area became a necessity. With the aim of drilling around 200 wells in the South Area, it was performed in 2011 the acquisition of a 3D3C seismic survey of 91 Km2, the first industrial 3D3C in the Orinoco Heavy Oil Belt, with the following characteristics: the use of DSUs, a record length of 8 seconds, a bin size of 10 m x 10 m and a nominal fold of 66. Parameters and characteristics were optimized from previous 3D3C pilots to improve the quality but also to perform elastic inversions from PP and PS seismic waves to better understand the subsurface and to get a reliable reservoir characterization.

A PP seismic Fast Track has been produced and has been used to start the delineation (vertical and slanted stratigraphic wells) and the development programs of the South Area, thus proving immediately its added value for Petrocedeño.

The lessons learned during the seismic design and acquisition will be useful to the future acquisitions in the Orinoco Heavy Oil Belt.
Resource Potential of Natural Gas Hydrate Deposits Offshore Trinidad
Authors: Greig-Jones Shelly-Ann , Marcelle-De Silva J. , Thomas S.
Published: June 2012

Seismic data and gravity cores indicate that natural gas hydrate deposits are present in the Columbus Basin off the East Coast of Trinidad. These data led to the initiation of a research program aimed at delineating and characterizing this unconventional resource. Already the areal extents of deposits in two offshore blocks have been estimated. In this study, the theoretical thickness of the hydrate stability zone for one of the blocks was estimated and additional reservoir properties collated from globally located hydrate-bearing strata. These data were used to conduct a parametric study on the potential volume of natural gas in the block.

Quantification of this unconventional gas resource is important since natural gas is a premium fuel and its use is likely to increase in the short and medium term. Factors contributing to this phenomenon are (i) the increasing global energy demand, (ii) natural gas is environmentally friendlier than oil and coal in terms of total emissions, and (iii) oil and coal, which are high carbon fuels, and greater contributors to global warming. In addition, international interest stems from the fact that gas hydrate deposits are affected by temperature and pressure, and release of methane from these deposits can occur if there are certain changes to these conditions. This could impact oceanic and atmospheric chemistry, and in due course climate.

The data collated from the globally located hydrate-bearing strata indicated that porosities were generally greater than 16%, and hydrate saturations were as high as 80%. These data along with the theoretical thickness of the gas hydrate stability zone indicated that the potential volume of natural gas in situ may be greater than 1 TCF.

This finding is significant since if the technical challenges associated with producing this unconventional resource are overcome, the natural gas stored in this hydrate deposit represents a potential additional source of gas which can be used to help meet Trinidad and Tobago‟s future energy needs.
A Greater Dolphin Area Case Study Part 1: Defining Geological Uncertainty
Authors: Taylor K. S. , Kalita N. , Dowlath J. , Jegede O. , Ameerali R.
Published: June 2012

The Dolphin Field is located in the East Coast Marine Area, approximately 60km off Trinidad. It comprises a 5,000 feet succession of stacked, unconsolidated, Pleistocene shoreface-deltaic sandstones and mudstones lying within a three-way dip, fault closure. The field is complicated by poor seismic data due to gas attenuation, fault shadow effects, large velocity variations and noise in the overburden. As a result the use of seismic amplitudes for fluid determination is unreliable and fault interpretation problematic.

Despite over 15 years of production, 5 exploration wells and 13 development wells there remains a high level of subsurface uncertainty. Specific areas of uncertainties include: zones of poor correlation as a result of large-scale sediment deformation; the configuration and sealing properties of both structural and syn-sedimentary faults; the effects of thin-bedded deposits (forming over 50% of the Dolphin reservoir intervals) on reservoir pay and connectivity; and the absence of all but one proven Gas Water Contact (GWC).

Defining the range of these uncertainties has a key impact on the range of GIIP outcomes, the resultant development plan and subsequent reservoir management. This paper will discuss the challenges and impact of these uncertainties on the Dolphin Field. The uncertainties identified on Dolphin form the basis for uncertainty planning in the development of subsequent analogous greenfields also within the Greater Dolphin Area.
A Greater Dolphin Area Case Study Part 2: Streamlining Subsurface Uncertainty for Business Value
Authors: Persad Shelley , Velarde Javier , Lerza Alejandro , Taylor Katy
Published: June 2012

Calculating and determining a range of Gas Initially In Place (GIIP) is one of the major challenges faced when optimizing a field development plan. Desired outcomes can be further complicated by geological characteristics which are uncertain and difficult to quantify; to the point where a physical solution is unattainable without the use of inappropriate and complicated software applications. Plackett-Burman Experimental Design (P-B ED) is a published and an innovative process which is simple, logical and efficient in managing uncertainty and appropriately defining the range of possible outcomes by utilizing simple, every day and user friendly software. PB ED allows for effective planning and mitigation for the most likely outcome and the least. The geological uncertainties incorporated in the analysis are described in Part 1 of the Greater Dolphin Area Case Studies; SPE 158545.

The P-B ED workflow was applied to determine the range of GIIP for the Starfish field. Starfish is currently not on production and is located off the East Coast of Trinidad and is being considered for development. It is owned as a joint venture between Chevron and BG Trinidad and Tobago (operator). One of the main objectives of this process was to identify the P10, P50 and P90 geo-models which are then used for dynamic modeling and field development planning.

The Unconstrained Development Study (UDS) process was utilized for the field development planning of Starfish. A UDS is a process used to determine the optimum number of wells and their locations to develop a field. The P50 dynamic model was populated with hundreds of wells which were subsequently eliminated based on well performance and water breakthrough. This is an iterative process which has been recognized as an effective workflow for field development planning. Once the P50 reservoir outcome was optimized, both P10 and P90 geo-models were tested to ensure that the proposed development plan was also valid for the geological range. After applying the UDS process; it was determined that four wells were required to optimally develop the field. This paper discusses the Experimental Design and UDS workflows, summarizes the lessons learned and recommends best practice for field development optimal recovery efficiency.
Formation Pressure Estimation and Its Impact On Well Design: A Case Study From The Greater Dolphin Area
Authors: Ameerali R. , Saisbhan A. , Adeleke A. , Harripersad N. , Parotidis M.
Published: June 2012

Pore pressure studies have been a key consideration in well design; both from a drilling design and well deliverability perspective. In the drilling of an exploration opportunity, and in the absence of direct pressure measurements, pore pressure estimation becomes even more critical in the delivery of a safe, cost effective and potentially productive well.

In a previously drilled key well in the Greater Dolphin Area there were no direct pressure measurements taken through one of the tested zones where there is potential for an updip accumulation. To fully appreciate this exploration opportunity, pore pressure estimation is required for both well design and subsequent well cost assumptions.

Given the lack of pressure data for this prospect, pressure uncertainty ranges, supplemented by analogue well data feeding into a geomechanical model were utilized for well design. The geomechanical study defined the appropriate mud weight windows and guided the casing design. This pore pressure analysis also fed into the estimation of production rates and safe operating drawdown envelopes which are critical to the delivery of highly productive wells.

Assumptions on the well design and the expected production rate provided the basis of drilling duration and cost and thus the economic viability of pursuing the prospect. Through this uncertainty management, this exploration opportunity, if deemed viable, can be included in future development programs and if successful, add to the gas reserves of the Greater Dolphin Area.
Leaseout/Farmout Operations in Trinidad - Past, Present and Future
Authors: Ramroopsingh A. , Ramgattie C.
Published: June 2012

The market decline of the late 1980’s resulted in a number of multinational companies retreating from the local oil production scene on the island of Trinidad and Tobago. As such, the state-owned Oil Company at the time was left with over 5000 inactive wells and a large amount of idle equipment such as well servicing rigs, trucks and pumps. The Government of Trinidad and Tobago in a bid to rejuvenate the declining industry issued the mandate that small land based fields which were uneconomical to be produced from should be leased and farmed out to smaller independent local operators in a bid to augment production-a policy that has remained true until the present.

This study reviews the main elements and differences of the Farmout and Lease operatorship as well as highlights the successes and provides suggestions for future roles. The major difference between the LO/FO operations is that with the lease operations, only the well is leased out and the operator has limited rights for the development of petroleum resources in the block. Production is generally confined to the formation across which the well was initially perforated. As a result, there is no drilling obligation. With the Farmout operatorship the operator has unlimited rights to petroleum development in the block at any depth and also is required to drill new wells to develop these resources. This in turn affects the Capital Expenditure (CAPEX) as the type and diversity of expertise required for the operatorship varies for each. During the period 1991 to 1999 the Leaseout program was responsible for the reactivation of 25 dormant blocks. In the same period the Farmout program was responsible for increased activity from 121 wells; 85 of which were newly drilled.

The Leaseout program has shown over 24 MMBBLS of oil recovered to date with the average production for the year 2010 being 4870 bopd. This represents 5.4% of the country’s average daily production. The Farmout program has shown 8MMBBLS of oil recovered to date with an average rate of 1650 bopd in 2010 (1.8% contributions). Developments in these programs include the legal modification of contracts in the form of the IPSC (Incremental Production Sharing Contracts) introduced in 2010.

The future of the programs hold potential for expansion of operations into marine-area and small scale steam flooding and CO2 injection targeting smaller pockets of hydrocarbons on-land and stranded gas offshore. But there will be the need for technical skills to be acquired and passed on if such ventures are to be undertaken successfully and economically.
Surgical Options In Oroantral Fistula Treatment
Authors: Borgonovo Andrea Enrico , Berardinelli Frederick Valerio , Favale Marco , Maiorana Carlo
Published: June 2012

Oral fistula (OAF) is a pathological communication between the oral cavity and maxillary sinus which has its origin either from iatrogenic complications or from dental infections, osteomyelitis, radiation therapy or trauma. OAF closures can be achieved using different flaps which show both advantages and limitations. Therefore they all need careful consideration in order to select the best approach depending on the situation. The most widely employed flaps are of three types: vestibular flap, palatal flap and buccal fat pad Flap(BFP). The authors present three cases of OAF with the different techniques. It is suggested that the buccal flap is best applied in the case of large fistulas located in the anterior region, the palatal flap is suitable to correct premolar defects and the BFP flap for wide posterior OAFs.
Reaction of different tomato cultivars toward race 1 of Fusarium oxysporum f. sp. lycopersici
Authors: Djordjevic Mladen , Vatchev Tzenko , Girek Zdenka , Sevic Milan , Zecevic Bogoljub , Zdravkovic Jasmina , Ivanovic Mirko
Published: June 2012

The aim of this study was to examine the reaction of different tomato
cultivars towards race 1 of Fusarium oxysporum f. sp. lycopersici. The
researched tomato cultivars were: Adonis, Gruzanski zlatni, Jasmin crveni,
Narvik SPF and SP109, breeding lines Hom-3, Hom-4, L-4, S-49, S-31, S- 35,
SPA, SPR,V-100, 34/56, 93/10 and 93/16. Reaction to pathogen were tested in
F1 generation, as well, in combination of 93/16 x V-100, S-35 x L- 4, S-49 x
SPA, 34/56 x SPR, S-49 x Hom-4, 93/16 x Hom-3 and 93/10 x S- 31. Plants were
inoculated by submerging wounded roots in to pathogen suspension. Disease was
assessed 30 days after inoculation. After evaluation 15 cultivars expressed
resistance toward this pathogen. Among them 93/10 x S-31, Hom-3 and 93/10 had
average disease rating 1,0. Other genotypes had average disease ratings as
follows: Narvik SPF and S-49 (1,1), 34/56, Hom-4 and S-49 x Hom-4 (1,2),
while Adonis, 93/16 x Hom-3, 34/56 x SPR and 93/16 x V-100 had average
disease rating 1,3. Cultivars SPR and 93/16 had 1,7 ADR, meanwhile Sp-109 had
1,8 average rating. Genotypes SPA (2,1), S-49 x SPA (2,1), V-100 (2,2) and
L-4 (2,6) belong to the group of tolerant genotypes who did not expressed
typical symptoms of chlorosis and wilt of plant but expressed some level of
necrosis of xylem in lower part of plants. Most sensitive to fusarium wilt
were S-35 x L-4 (3,3), S-35 (3,5), S-31 (3,6), Gruzanski zlatni (3,8) and
Jasmin Crveni with average disease rating of 4,0.
An empirical study of exchange rate pass-through in China
Authors: Jin Xiaowen
Published: June 2012

This paper seeks to estimate exchange rate pass-through in China and
investigate its relationship with monetary policy. Linear and VAR models are
applied to analyze robustness. The linear model shows that, over the long
run, a 1% appreciation of NEER causes a decline in the CPI inflation rate of
0.132% and PPI inflation rate of 0.495%. The VAR model supports the results
of the linear model, suggesting a fairly low CPI pass-through and relatively
higher PPI pass-through. Furthermore, this paper finds that, with the fixed
exchange rate regime, CPI pass-through remains higher. The exchange rate
regimes influence on CPI pass through, combined with the fact that
appreciation diminishes inflation, suggests that the Chinese government could
pursue a more flexible exchange rate policy. In addition, reasons for low
exchange rate pass-through for CPI are analyzed. The analysis considers price
control, basket and weight of Chinese price indices, distribution cost, and
imported and non-tradable share of inputs.
Heterogeneity of growth in the west Balkans and emerging Europe: A dynamic panel data model approach
Authors: Josifidis Kosta , Dragutinovic-Mitrovic Radmila , Ivancev Olgica
Published: June 2012

This paper explores the heterogeneity of growth in the Western Balkan and
Emerging European economies. For that purpose, growth determinants are
estimated in the period 1997-2009 by dynamic panel data models. The chosen
period provides a comparison for the model results with those estimated for
the period up to 2007 in order to analyze changes caused by the global
instability. According to the main findings of the paper, macroeconomic
stabilization and structural reforms still matter in determining economic
growth, but foreign direct investments and economic integrations seem to have
the most important role in stimulating growth in the observed countries.
Moreover, significant positive effects of foreign direct investments and
economic integrations produce differences in growth paths between Emerging
European and Western Balkan economies. Sharp decrease of foreign inflows in
2008 determined contractions of growth rates firstly in Emerging European
economies with subsequent spill-over on the Western Balkan economies during
2009. Consequently, in the period of global instability, differences between
two groups of economies become even more obvious.
Inflation persistence in central and southeastern Europe: Evidence from univariate and structural time series approaches
Authors: Mladenovic Zorica , Nojkovic Aleksandra
Published: June 2012

The purpose of this paper is to measure inflation persistence in the
following countries of Central and Southeastern Europe: Slovakia, the Czech
Republic, Poland, Hungary, Romania and Serbia. The study sample covers
monthly data from January, 1995 to May, 2010 for Poland, Hungary and
Slovakia, from January 1994 to May, 2010 for the Czech Republic, and from
January, 2002 to June 2010 for Romania. The shortest sample used, from
January, 2003 to September, 2010, was for Serbia and is due to the late start
in the transition process. The results of this study enriched the existing
ones on this topic by extending the sample period to cover even the recent
years of relatively higher inflation rates and by including Romania and
Serbia, which were not previously considered. The study led to two main
findings: first, inflation of moderate to high magnitude persistence in
Hungary, Poland, Romania and Serbia, and inflation of smaller order
persistence in Slovakia and the Czech Republic was detected within the Markov
switching model approach. In addition, the changes in inflation persistence
often correspond to changes in variability and mean of inflation. Second, New
Keynesian Phillips Curve represents a valid structural approach to describe
the inflation dynamics in this region. In all the six cases studied, weights
on backward and forward looking behaviors were significant, while the impact
of the driving variable was insignificant only once. It is found that
significant influence of the economic driving variable can be captured by
real gross wage inflation and real broad money growth. The estimates show
that the backward-looking term plays an important role in determining the
inflation dynamics. Similar conclusions are drawn by using quarterly data in
econometric estimations for the selected countries.
Morphological variability of populations of Dactylorhiza maculata (L.) Soó and D. majalis (Reichenb.) P.F. Hunt et Summerhayes (Orchidales, Orchidaceae) from Stara planina mountain (Serbia)
Authors: Radak Boris , Rat Milica , Anackov Goran
Published: June 2012

Comparative morphological taxonomic analysis was conducted on two populations
of Dactylorhiza maculata (L.) So? 1962 and one population of D. majalis
(Reichenb.) P. F. Hunt et Summerhayes 1965 from the area of Stara planina
mountain in order to determine new characters that could be used to
distinguish these two species and characters that could eventually be used
for defining infraspecific taxa within these species. Taxonomic studies have
included processing of quantitative and qualitative characters. A total of 60
characters were analyzed, out of which 34 quantitative and 26 qualitative.
Analysis of quantitative and qualitative characters included 90 specimens -
60 of D. maculata and 30 of D. majalis. Based on the results obtained by
multivariate statistical analysis and literature data, we selected sets of
taxonomic characters that allow a clear differentiation of infraspecific
forms within the species D. maculata, which is characterized by intensive
variability on the selected localities on Stara planina.
Going beyond the ‘PISA Shock’ Discourse: An Analysis of the Cognitive Reception of PISA in Six European Countries, 2001–2008
Authors: Pons Xavier
Published: June 2012

The aim of this article is to open discussion by analysing the cognitive reception of PISA in six European countries which were studied in the European collective research project KNOWandPOL (Knowledge and Policy in Education and Health Sectors). Reception does not mean here a simple vertical transmission of messages from the international level to the national one, but a cognitive activity when messages are constantly accepted, refused or renegotiated by actors. The adjective ‘cognitive’ means that the focus is on the cognitive aspects of this constant process of redefinition, trying to understand what kind of knowledge actors talking about PISA in the public debate mobilise, in which context and for what reasons. To do so, the author proposes a specific theoretical framework which largely draws on some concepts and theoretical tools from the sociology of translation and their adaptation in policy analysis).
What PISA Knows and Can Do: Studying the Role of National Actors in the Making of PISA
Authors: Grek Sotiria
Published: June 2012

This article builds on previous research which has emphasised the role of comparisons of educational performance in creating visibility and borderlessness, and moves the argument a point further. The article claims that apart from increased visibility, what the Programme for International Student Assessment (PISA) has brought to education systems in Europe is interdependence. This is because one of the often ignored or too obvious effects of comparison is that, first, it creates representations of educational realities (the first level of the construction of the story) and, second, it takes those previously separate and disparate pieces and brings them together into a whole, into one single entity — in the case of PISA, the league table, the report, the speech and so on. PISA has created such interdependence among education systems in Europe and beyond, and has simultaneously created the dependence of this new reality on the continuous production of PISA data. This is precisely how PISA has secured its existence. Although the PISA ‘spectacle’ may have become slightly banal, nevertheless PISA is the sine qua non of education policy-making in Europe. This is certainly the case for the European Commission and its use of the PISA data to govern. Following the constructed imaginaries of economic globalisation, which see nations and societies as mutually dependent, PISA has substantially contributed towards a fiscalisation of the thinking behind reforming education systems and the narratives and imaginaries that construct this thinking. If economies are now globally exposed, so is education (or so it has to be).
Triiodothyronin, Thyroxine and Thyrotropin in Vitiligo
Authors: Subba K , Karn D , Khatri R
Published: June 2012

BackgroundVitiligo is a common pigmentary disorder of the skin, affecting individuals globally. Not only is this ailment psychologically incapacitating, it also has a high incidence of autoimmunity, signifying that its manifestations may be the portrayal of dysfunction of immune system. ObjectiveThe aim of this study is to find out the situations of abnormal thyroid function test (TFT) in vitiligo patients. MethodsA prospective cross sectional study was conducted at the Dhulikhel Hospital, KUTH, Dhulikhel during November 2008 to January 2011 with the objective to assess the thyroid function tests in vitiligo patients. ResultsTotal 66 vitiligo patients with male 30 (45%) and female 36 (55%). Total 26 (39.39%) vitiligo patients have been found to have abnormal thyroid function test. Among them 10 had abnormal T3, seven had abnormal T4 and 12 had abnormal TSH level. Thyroid function test were normal in other vitiligo patients. Total seven vitiligo had high level of T3 than normal value, four male and three female. Two had higher level of T4 above 2.0 ng/dl and all were male, while five had abnormally low level of T4 with three male and two female. There were seven vitiligo patient with increased T3 level and three with decreased T3 level, among them six were males and four were females, the age group was ranged from seven to 68 years old. The T4 level were found abnormal in seven vitiligo patients among which five were males and two were females with the age group ranging from 7 to 51 years. ConclusionsThere has been significant association of thyroid disorder in the patient with vitiligo. Therefore, patient with vitiligo need to undergo thyroid function test to rule out the thyroid disorder and prevent from long-term complications.DOI: http://dx.doi.org/10.3126/kumj.v9i2.6279Kathmandu Univ Med J 2011;9(2):7-10