bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving Weight to Weight Connection Time to Lower Well Construction Cost
Authors: Svensson Inge , Mobley Kassie E. , Aming Anthony J.
Published: August 2016

Even with lower rig rates due to the lower oil prices, the daily cost of running a drilling rig is still high. When an offshore rig is drilling, this can extend well over 100.000 USD an hour with all personnel and services onboard. Monitoring and improving rig and drilling key performance indicators is therefore an important factor that can lower well construction cost.

This paper will focus on how we can monitor, visualize and improve weight to weight connection time and related sub components over time. In addition we will look into real-time monitoring of weight to weight time while drilling and which corrective actions can be taken. We will express factors that are contributing to excess usage of time in some sections drilled, outlined with examples and use cases. Very often we do see large potential for improvements that again will save rig time.

Typically we can discover extended circulating time including forward and backward reaming and excess time used on taking surveys. On some rigs, we also observe slip to slip time to be below average. Wired pipe operations compared to normal mud pulse telemetry will also be presented.

Statistics will be presented with a composite average best performance for a number of wells. In our conclusion and findings, we will present documented results from rigs that have undergone rig performance programs over time and the resulted potential cost savings.
Using Nudge Techniques to Influence Behaviour in an Engineering Office
Authors: Healey M. , Parker K. , Saldin L.
Published: August 2016

Nudge techniques have led to a revolution in the way organisations think about the hierarchy of choice. Small changes in the way choices are presented — nudges — can have a significant impact on behaviour. This article considers the application of nudge techniques to engineering offices, a working environment populated by a high proportion of skilled professional individuals.

The techniques presented are based on the Nudge methodology, first published in 2008. The authors draw on lessons from direct experience in engineering offices, and from results presented in the public domain. This includes techniques developed by government "nudge units", such as those instituted by the Cameron and Obama governments. The techniques presented are broadly based on the EAST (Easy, Attractive, Social, Timely) framework developed in the UK and intended for application by managers within private industry.

Engineering offices present a special challenge compared with government and other industries. Managers must maintain a functional and profitable environment within an intelligent, diverse, and wilful group of employees. Nudge techniques are particularly applicable to this environment as they offer a mechanism to implement change without prescriptive rules, and without organizational upheaval. In nudge parlance this is known as "libertarian paternalism". This article looks at several potential applications, specifically: embedment and reinforcement of an organization-wide commitment to safety culture; better adherence to document control procedures; improved efficiency and general job performance; improved commercial focus; reduction of anti-social or destructive behaviour; improved office-wide communication, and; increased job satisfaction.

The nudge techniques in this paper are presented in a practical way, designed for direct use by managers. They account for the unique features and requirements of an engineering office environment, and are based on the premise that a small change can lead to significant, measurable improvements.
Enabling Real-Time Distributed Sensor Data for Broader Use by the Big Data Infrastructures
Authors: Yang Don , Denney Tommy , Bello Oladele , Lazarus Sony , Vettical Celestine
Published: August 2016

Petroleum exploration and production processes typically generate enormous amounts of petro-technical data using sub-surface and surface sensors. The acquisition, transferring, managing, and interpreting of these huge sensor data, as well as the decision making based on it has led to the advent of the digital oilfield phenomenon in the petroleum industry. To achieve improved efficiency, accuracy, and performance, many E & P operators are aiming to apply fiber optics distributed temperature sensing data management technologies to add volume. Currently, high volume distributed sensing data transfer, storage, processing, archiving, retrieval and exchange system in the petroleum industry still face big challenges such as high cost of hardware and software, complicated implementation and deployment framework that is difficult to sustain such as scale and upgrade, as well as compatibility for data provided by different vendors. An efficient online real-time elastically scalable system that enables fast retrieval from big data infrastructures is therefore essential.

This paper describes a scalable web based enterprisefiber optic infrastructure for data exchange, management and visualization. This platform applies multi-tier client-server architecture, scalable distributed databases, PRODML (Production Markup Language), and web services technologies to provide a reliable mechanism to bring fiber optic data from the field site to the corporate network in real-time and enable user to visualize the data anywhere, any time. The support of PRODML industry standard make it vendor neutral and allow data exchanging from different systems and sharing data among users and different applications. The distributed Cassandra database enables the scalability to handle the fiber optic big data in a high performance and efficient way. Finally, the global inventory management system allows keeping track of changes to the asset and the instrumentation configuration over the life of the distributed sensor systems, as well as the ability to correlate the measurement data to the proper asset configuration. A case study is presented that demonstrates successful field testing to verify the functionalities of the newly developed system for high data volume distributed sensors. Specific attention is given to many advantages being offered by this new framework over existing ones.
Efficient Optimization Strategies for Developing Intelligent Well Business Cases
Authors: Vasper Adam , Mjos Jon Endre , Duong Tran Thi
Published: August 2016

In this paper, we evaluate optimization techniques to develop, or support, business cases for Intelligent or Smart Wells. A commercial reservoir simulation platform and two reservoir models based on published work are used. Recommendations are made on which methods are most appropriate for large or small numbers of flow control valves (FCVs), available computing power and other parameters.

Optimization techniques are categorized as either Closed Loop or Model Based. Closed Loop or Reactive methods respond to specific, measured properties such as water-cut or gas-oil ratio, by opening or closing downhole flow control valves. Model-Based methods use reservoir models to determine the optimal set of flow control valve positions versus time. They can, therefore, behave in a defensive or proactive manner to delay the production of unwanted fluids, as well as a reactive manner, to choke back sections of the well producing unwanted fluids. In this paper, Closed-Loop and Model-Based methods are compared in terms of computational cost. A simple procedure for defining the constraints used in the optimization process is proposed. The procedure is shown to increase the efficiency of the optimization process significantly.
Real-Time Interactive Remote Display of DTS and DAS Data for Well Treatment Optimization
Authors: Dickenson Paul , Brants-Menard Sacha , Telsey Mike , Stanbridge Adam , Wilson Colin , Akin Josiah , Roman Nathan , Anifowoshe Olatunbosun , Yates Malcolm E. , Carney B. J. , Costello Ian , Hewitt Jay , Warner Ryan
Published: August 2016

The value of data can be greatly enhanced if the data are available at the right location and in a timely fashion. This can be a particular challenge for the often considerable volume of data collected using distributed measurements such as Distributed Temperature Sensing (DTS) and Distributed Acoustic Sensing (DAS). In this paper we describe a novel solution using multiple levels of data reduction yielding data of different sizes and fidelity. These are then transmitted for viewing at the wellsite, in real time at a remote location, or subsequently for post-job evaluation. This approach is demonstrated using a case study of a well stimulation operation from the United States.
Risk Based Management of Wells Safety-Related Software Systems
Authors: Reed D. , Turnbull J.
Published: August 2016

The Operator has long recognized the risks associated with specialist well engineering and wells services software and how insufficient management could have consequences to both safety and the environment. Sawaryn et al. (2003) laid out a set of principles for improving the management and use of Safety-Critical drilling engineering and well services software.

Through a series of initiatives, the Operator has developed these principles into a risk based management practice aligned to international standards; IEC 61508 (2010). This has enabled better understanding by global wells and IT on the influence software systems have on group loss of well control risk barriers. It has also enabled the creation of a more robust management framework.

A significant development has been to simplify the classification and differentiation between Safety-Critical and Safety-Related systems. It was recognized that applying a broad brush definition of "Safety-Critical" to wells applications created a high burden of responsibility and weakened the definition of Safety-Criticality. For example a system with no human interaction before an action occurs should be managed more rigorously than one whose output can be validated and corroborated. When applying these criteria to wells software it was found that none were Safety-Critical, therefore the scope of this paper is confined to Safety-Related software.

A risk based approach has been used to enable easier classification of software, removing some of the ambiguity prevalent in the past. This has reduced the risk for project delivery and IT support operations. Using risk based approach has also allowed a more objective approach to management, enabling better measurement for the controls discussed in this paper.

Work in this area is still relatively immature and there remain many challenges. For example, data integrity can be difficult to manage and can weaken controls such as algorithm validation. Additionally complex systems used by wells but owned by other upstream functions can be difficult to manage unless those functions follow the same methodology.

This paper outlines the initiatives the Operator has taken to reduce the risk presented by Safety-Related software, highlighting the benefits, challenges and opportunities.
Surface Management of Gas Breakthrough in Thin Oil Rim Waxy Reservoir: A Case Study
Authors: Agrawal A. , Leeuwen P. V. , Demirbas B. , Hajj J.
Published: August 2016

With technological advancements, new and improved techniques have progressively been deployed to maximize recovery from a thin oil rim development. While some of them have a lasting influence on the well behavior such as placement of the well bore in the oil column, others such as zonal control using Sliding Side Doors (SSDs), Interval Control Valves (ICVs) or Interval Control Devices (ICDs) provide flexibility for altering well performance during operating life of the well. However, any intervention be it the subsurface zone manipulation or surface choke manipulation or ICV control needs to be justified in view of the anticipated gains against the risk incurred and resources required for the intervention on the basis of well performance (test data) and subsurface interpretation.

The field for this case study is a thin oil rim with a large gas cap and a high wax content facing twin challenges – gassing out of wells and waxing of tubulars and flowlines – both of which require an optimization of preventive interventions to minimize deferment and corrective interventions. The required interventions such as choke and gas lift changes, zone changes, scraping, hot-oiling, steaming and pigging consume significant man-hours for surveillance, planning, execution and monitoring of the impact of the job on well performance. The desire to follow each intervention by a well test for system optimization overwhelms an already stretched routine well testing schedule. The resultant deferment due to sub-optimal production was estimated to be 10-15%. The solution was in breaking down the problem into mini-challenges and addressing them by deploying robust technologies and adopting smarter ways of working.

In this paper a simple surface technology that helps managing gas breakthrough is presented. This technology when combined with smart surveillance techniques enables efficient Well, Reservoir and Facility Management (WRFM) for thin oil rims with added wax challenge. Following impacts have been seen: An average increase in production by 10% was realized. The project payback was less than 2 months.Up to 80 man-hours per week were freed allowing team to focus on additional barrel generating opportunities.Reduced Health, Safety, Security and Environment (HSSE) risk corresponding to reduced well intervention besides stabilized production.Reduced deferment by optimal timing of preventive intervention and reduced risk of incurring cost and deferment from a corrective or reactive intervention.Improved team productivity and fresh energy from use of smart ways of working.

The novelty of this surface technology for managing gas breakthrough is in its ability to optimize, accelerate and thereby squeeze production from a thin oil rim development in the license period. The resulting production stability then provides a basis for deploying smart surveillance techniques for sustainable increased efficiency.
Robust Derivative Estimation for Decline Analysis from Noisy Production Data
Authors: Subrahmanya Niranjan , de Waele Stijn , Liu Wei , Tewari Ashutosh , El-Bakry Amr , Pais Darren
Published: August 2016

Efficient reservoir management requires regular analysis of large amounts of data to provide insights for decision making in a timely fashion. Well testing provides a key source of data for production surveillance and optimization by estimating oil, water and gas rates at irregularly sampled testing times. Although a significant amount of effort is spent on ensuring the quality of these well tests, the acquired data is still likely to have large uncertainties due to the complexity of flow dynamics, and challenges in multiphase flow separation and measurement. The resulting production history measurement for a well is therefore a noisy, unevenly sampled time series with potential significant outliers. A key point of interest is to perform decline analysis, which involves monitoring production trends (the derivative of the production time series) to ensure optimal well and reservoir performance. In addition to noise, the estimation of production trends is complicated by the effect of improved/enhanced recovery mechanisms (such as water flooding, steam injection etc.), well stimulation, and communication between wells, all of which may cause the production to deviate from expected parametric decline curves. As a result of this complexity, decline analysis typically requires significant manual effort in cleaning and segmenting the data and then fitting parametric curves to the extracted segments; this is challenging to do on a regular basis for all the wells. A robust and automated method to estimate production trends will enable continuous production surveillance and optimization in fields with hundreds to thousands of wells. In this paper, we report an effective method to address this challenge using a non-parametric approach based on robust regression for joint time series modeling and derivative estimation. Some key advantages of this approach over a conventional approach are a) it does not require manual data segmentation b) it is tolerant to a high amount of noise including some bad outliers c) it does not require manual choice of parametric decline curves. We compare results with conventional approaches and demonstrate benefits on synthetic production data.
Leveraging Change Agent Networks to Enable Successful Transformation
Authors: Mortman Michelle , Zeringue Amy
Published: August 2016

It has been said, "Change is difficult. Not changing can be fatal." In today's ever-changing business environment, we are required to change and adapt quickly. If we then add additional factors such as complex, transformational projects across distance and function, change becomes even more difficult. Finding ways to effectively manage change within your organization by leveraging Change Agent Networks can be a means to facilitate an organization's ability to evolve and change for the future.

In intelligent energy projects where people, process, and technology must come together to enable true transformation, implementing meaningful and sustainable change can be challenging. Building collaborative partners from key stakeholder groups is necessary to bridge gaps that often exist in complex project environments where distance and function serve as additional barriers to project success.

Change Agent Networks are groups of individuals representing the target audience of a project. When identified early on, they can provide critical input and support to a project throughout design and development activities to ensure the solution satisfies the needs of the business and ultimately delivers business value. Further participation in implementation and beyond can help to ensure the project is received positively by the business and that business results are reported.
A New Communications Protocol for Real-Time Decision Making
Authors: McKenzie William , Schave Robert , Farnan Mark , Deny Laurent , Morrison Pete , Hollingsworth Jay
Published: August 2016

The current standard infrastructure for delivery of wellsite data uses SOAP Web services over the HTTP protocol. More than a decade of experience in this environment has revealed significant challenges for timely delivery of wellsite data. At the same time, data volumes are increasing exponentially in an ever more connected world. To address these issues, an entirely new protocol stack, based on the latest available Web standards, has been developed.

The Energistics Transfer Protocol, or ETP (Energistics 2016), is a new communications protocol specification that enables efficient transfer of data between rig site, office, and applications. The initial use case is for real-time data; however, it is anticipated that ETP will be expanded to include functionality for historical data queries.

ETP has been specifically envisioned and designed to meet the unique needs of the upstream oil and gas industry and specially to facilitate the exchange of data in the Energistics family of data standards, which includes WITSML™, PRODML™ and RESQML™.

One of the initial goals of ETP is to support everything from WITS-style devices through to html5-enabled mobile devices with a single, simple-to-implement protocol. Some of the main use cases are to move real-time data between applications, including: Device to wellsite provider (acquisition system)Transfer from a wellsite provider to a WITSML store (aggregation server)Transfer of data from WITSML store to WITSML store (server replication)Transfer of data from WITSML store to client applications

ETP defines a notification mechanism so data receivers do not have to poll for data and can receive new data as soon as they are available from a data provider.

This paper presents the challenges faced by the industry, a description of the alternatives and technology choices that have been made, and an analysis of performance improvements based on laboratory and field trials for both WITSML (drilling) and RESQML (earth modeling/reservoir).
Operations Excellence Maximizes the Value of the Digital Oilfield Implementations
Authors: Coffin Guillaume , Florez Fabian , Salim Muzahidin Muhamed
Published: August 2016

In a competitive environment and uncertain economic conditions, running flawless operations is becoming an even more acute concern. This is true for any operator and for service companies providing production optimization services. To this end, a digital oilfield program was implemented across several assets as part of an operations excellence program.

The operations excellence program was designed as a vehicle to maximize the performance of operations and implement a common culture in the assets. This comprehensive program covers all main operational processes of the asset. Each of the domains is addressed from the point of view of processes, people, and management systems, to implement best practices and achieve a common culture. A well-defined methodology enforces the change.

The digital oilfield program was designed from the beginning as an essential element of the operations excellence program, one with impact on the work processes and value generated by the assets. It comprises a standard that defines the minimum requirements, an implementation methodology, a technical guidance, and audits. When combined, these programs provide efficient integrated management of the assets.

If the digital oilfield is usually seen as a technical project focusing on infrastructure, its implementation as part of the operations excellence program enables achieving three major objectives: modifying operational practices to take the technology into account, framing the digital oilfield to optimize its value, and feeding operations excellence with reliable data to maximize decision quality.
Real-Time Surveillance, Analysis and Control Via Secured Digital Intelligent Technology in Joint Operations – Wafra Field
Authors: Bahbahani Baqer , Jagannathan Rajaperumal , Heshmat Kareem , Mohamed Assem
Published: August 2016

Applying Smart techniques and latest digital intelligent technology in oil field created a new vision of well surveillance. Communication is considered the backbone of any digital oil field project. The challenges faced while establishing field-wide communication from well-site to office. Monitoring and optimization software was rolled out over 900 artificially lifted wells in WAFRA field. The deployment depended upon certain factors such as hardware; including field instrumentation, data communication and integration of multiple data sources.

The deployment of static, dynamic, real-time data integration and remote well control were established via regular meetings and creation of user groups with common interest in daily operations to setup software solution that communicates with existing field level infrastructure located at each sub center. Intelligent setup allowed different teams to access real time data simultaneously, were decisions are taken on fully awareness of well behavior, creating a massive database for further analysis capabilities. The presence of historical, real time data and instant alarm detection in one screen gave the opportunity to track and evaluate well performance based on changes noticed.

Establishing communication involved opening a limited number of ports between field and office with the help of IT. However steady communication took a while to stabilize addressing different factors related to field network and security. Challenges faced included:

Firewall between field and office. Mapping between the down-hole gauges, variable speed drives and remote terminal units. Parallel scanning between an existing field level systems. Sub center level communication issues. Data security.

A data validation effort related to communication was made at one sub center between field instruments and subsequent relay to office. This established a standard that was set over the rest of field. A Management of change (MOC) was setup to address all high level issues related to the communication network. Due to parallel scan, the data transmission to user desktop was restricted to every two hours for most wells. The result of the collaborative effort between different teams build a strong, smart and reliable surveillance system creating a new way for real time analysis and powerful diagnostics engine.

Successfully deployment of the Life of Well Information Software for 900 artificially lifted wells in a partitioned neutral zone between Kuwait and Saudi Arabia, allowing all JO-engineers accessing LOWIS form different location (Saudi Arabia Chevron, Kuwait Gulf Oil Company and Admin building camp in Wafra) created a portfolio that enabled the engineers to maximize the performance of artificial lifted wells, adapt to changing well conditions and continuously monitor their assets.
Standardized D&C Rig IT Solutions Using a Software-Defined Data Center Approach
Authors: Milliet Christopher
Published: August 2016

Using virtualization and other pioneering technologies to develop a hybrid platform of servers, storage, and networking that can support a variety of rig based systems such as Real-Time Data Collection & Aggregation, Data Analytics, Collaboration, and other core IT services (email, file sharing, etc.) all of which are being hosted locally at the rig. In addition to the infrastructure components we have also adopted new application technology solutions in support of Geological & Geophysical Operations Wellsite Services, business partner connectivity and collaboration, and introducing tools to enhance telecommunications/network security at the rig. All of the activities have resulted in increased standardization, innovation and reliability of Information Technology systems supporting D&C and G&G Well Operations. The paper will highlight a variety of use cases where we have utilized variations of converged and software defined data center solutions based on uniform blueprint configurations at our rig sites. In particular, within our Deepwater Gulf of Mexico operations and Frontier exploration drilling programs in very remote locations. We will describe the cost savings benefits of moving to a standardized platform utilizing off the shelf IT technology solutions vs. oilfield specific IT technology tools. This paper will highlight our successes and lessons learned within this emerging area of focus and provide insight on where we believe the industry will be heading in the future and preparing for more data and technology issues such as Cybersecurity.
Deploying the Industrial Internet in Oil & Gas: Challenges and Opportunities
Authors: Baudoin Claude R.
Published: August 2016

Various industries have been applying the concepts and technologies of the Internet of Things (IoT) since it appeared, and are participating in – or driving IoT standardization and security efforts. The Oil & Gas industry is a relative laggard in applying the full capabilities of the Industrial Internet. Yet all the elements of success are lining up. There is now a published Industrial Internet Reference Architecture (IIRA), which means not having to reinvent the wheel. An ecosystem of device suppliers and system integrators is growing. And communication protocols such as the OPC Foundation's OPC-UA and the OMG's Data

Distribution Service are being interfaced to each other for seamless integration.

From case studies developed by others, especially the smart grid sector, we can derive useful guidance to improve operations, perform predictive maintenance, optimize production, improve safety and more. While these initiatives require an investment at a time of widespread, severe cost-cutting, this is also key to reducing production costs, automating labor-intensive tasks, and expanding remote operation, all of which contributes to the bottom line. Security is still a challenge, but the appropriate techniques exist and at least the issue is no longer being ignored. Data residency is also an obstacle, which will be tougher to remove in many regions because it is political and legal, not technical.

In this paper, we combine all this information to propose a roadmap for Industrial Internet application in O&G, give advice on organizing and governing such efforts (especially with respect to the frequent chasm between corporate IT and Operational Technology groups), and indicate resources that can help jumpstart such an effort.
Planning for Safe and Effective Execution of Work: Late Risk Identification
Authors: Sarshar Sizarta , Haugen Stein , Skjerve Ann Britt
Published: August 2016

When plans for execution of work offshore are prepared, a range of significant risks to HSE are only addressed late in the planning process. This paper highlights and discusses the challenges associated with late risk identification in the planning from the perspective of safe and efficient task execution offshore, and how to enable earlier identification of risks. The paper is based on data obtained from multiple sources based on the principle of triangulation: a literature study of major accident theories, analyses of investigation reports on hydrocarbon leakages, interviews with staff members involved in developing plans for offshore work, and two workshops on the topic of planning with two different operating companies operating on the Norwegian continental shelf. The study suggests that late risk identification reduces the quality of the plans and as a consequence the quality of their execution. Late risk identification leads to a range of inadequacies in planning, e.g. insufficient work descriptions, and relevant information which remains unaddressed during the planning process. These are all factors that can lead to unsafe and less effective task execution. As an example, work with hydrocarbon carrying systems requires end controls in several steps. Such control activities should be included in the job description when the job is established in the systems, rather than identified during the progression of the task execution process. The opportunities lie in earlier risk identification in the planning process and we specify in which phases improvements can be made. The study highlights the importance of quality in planning and how higher plan quality can be achieved through earlier risk identification for work to be executed offshore. This will influence work safety as well as efficiency.
Cooperative security strategy in the South Atlantic United States internal determinants and region ressignification
Authors: Machado Luiz Rodrigo
Published: August 2016

This paper discusses the importance of the South Atlantic to the cooperative security strategy of the United States of America. This analysis consider some internal determinants of the US Foreign and Security Policies, the importance of the sea for their strategy and a brief discussion of the actions taken by the United States Department of Defense in the region. The central role of the sea for the American Grand Strategy endorse the need for understanding the importance of the oceans, and consequently the South Atlantic. It was verified the importance of the sea for the consolidation of the American position in the world, and the South Atlantic as important strategic region to the United States. This importance is highlighted by the search for collaborative security initiatives to stabilizing the West African coast and combating offenses of low intensity as piracy, seeking to contain new threats and tackle non-state actors, recognizes multilateral institutions, such ZPCAS, and strategic partners, such Brazil.
Multiple quantum walkers on the line using hybrid coins: A possible tool for quantum search
Authors: Karafyllidis Ioannis , Hagouel Isaac
Published: August 2016

In this paper discrete quantum walks with different coins used for odd and
even time steps are studied. These coins are called hybrid. The calculation
results are compared with the most frequently used coin, the Hadamard
transform. Furthermore, quantum walks on the line which involve two or more
quantum walkers with hybrid coins are studied. Quantum walks with entangled
walkers and hybrid coins are also studied. The results of these calculations
show that the proposed types of quantum walks can be used for quantum search,
because the walker can be directed towards preferred directions and can also
be confined in certain segments of the line.
Synthesis, characterization, electrochemical studies and X-ray structures of mixed-ligand polypyridyl copper(II) complexes with the acetate
Authors: Adekunle Oluwafunmilayo , Butcher Ray , Bakare Oladapo , Odunola Olusegun
Published: August 2016

[Cu(phen)2(CH3COO)](ClO4).2H2O (1) and [Cu(bipy)2(CH3COO)]-(ClO4).H2O (2)
{phen = 1,10-phenanthroline, bipy = 2,2?-bipyridine}were synthesized and
characterized. The complexes were characterized by employying elemental
analyses, infrared and UV-Visible spectroscopy, room temperature magnetic
measurements and the crystal structures elucidated using X-ray diffraction
experiment. The redox properties of the complexes were also investigated.
Both structures have a square pyramidal CuN4O chromophore which exhibit
significant distortions due to long Cu-O [2.217(3) ? for (1) and 2.179 (1)
for (2)] and Cu-N [2.631(2) ? for (1) and 2.714(1) ? for (2)] bonds. This
distortion if further shown by the O-Cu-N bond angles [147.71(8) o for (1)
and 153.40(5) o for (2)]. The elemental analyses further support the
structural details unveiled by the single crystal X-ray diffraction analysis.
The infrared spectra shows the acetate vibrational frequencies at 1587
cm-1,1428 cm-1, 1314 cm-1 for (1) and 1571 cm-1, 1441 cm-1, 1319c m-1 for (2)
and the perchlo-rate bands at 1059 cm-1, 720 cm-1 (1) and 1080 cm-1,768 cm-1
(2). The broad d-d bands for the copper ion at 14,514 cm-1(1) and 14,535
cm-1(2) support the adoption of square pyramid geometries. The magnetic
moments for the two complexes are 1.83 B.M for (1) and 1.72 B.M for (2). The
peak to peak values of the two complexes show that the electrode reactions
are quasi-reversibile with ?Ep = 0.023V (1) and 0.025V for (2). In both
structures, there are ?-? intermolecular interactions in addition to hydrogen
bonding between the units.
Unsteady flow and load in 50% partial admission control stage with different admitting arc distributions
Authors: Gao Ke-Ke , Wang Shun-Sen , Shi Dong-Bo
Published: August 2016

Full three-dimensional unsteady numerical investigation on an axial air
turbine in 50% partial admission is conducted. The partial admission turbines
are under different unsteady loading and unloading process, as well as flow
parameters, respectively. The loss coefficient and static pressure
distributions at the key position are presented in detail to analyze the
nonuniformity originated from partial admission. The results show that the
nonuniformity decreases along flow direction and the efficiency of control
stage also decreases but with the uniformity improved downstream of the
rotors with increasing admitting numbers in equal partial admission degree.
The reasons for efficiency decreasing are reasonably explained with windage
and sector end losses presented by static entropy distributions. The periodic
changes of unsteady forces in amplitude and direction are also compared and
transformed in the frequency domain by FFT method. The largest
circumferential exciting force factor which is remarkably larger than the
corresponding axial exciting force factor decreases by 13.2% with the
increase of admitting arc number. Compared with the common distribution of
two symmetric admitting arcs, the maximum exciting force factor of triangle
admitting arc distribution drops 11.3% with the mere efficiency decrease of
1.32%. The multiple admitting arc turbines are more conducive to be applied
to submarines which concerns more about exciting force other than efficiency.
Efficiency and unsteady forces are both worth being taken into consideration
in the practical applications.
Numerical study of unsteady flow and exciting force for swept turbomachinery blades
Authors: Zhang Di , Jiao-Bin Ma , Jing Qi
Published: August 2016

The aerodynamic performance of blade affects the vibration characteristics
and stable operation of turbomachinery closely. The aerodynamic performance
of turbine stage can be improved by using swept blade. In this paper, the
RANS method and the RNG k-? turbulence mode were adopted to investigate the
unsteady flow characteristics and excitation force of swept blade stage.
According to the results, for the swept blade, the fluid of boundary layer
shifts in radial direction due to the influence of geometric construction. It
is observed that there is similar wake development for several kinds of
stators, and the wake has a notable effect on the boundary layer of the rotor
blades. When compared with straight blade, pressure fluctuation of
forward-swept blade is decreased while the pressure fluctuation of
backward-swept blade is increased. The axial and tangential fundamental
frequency excitation force factors of 15?forward-swept blade are 0.139 and
0.052 respectively, which are the least, and all excitation force factors are
in the normal range. The excitation factor of the forward-swept blade is
decreased compared with straight blade, and the decreasing percentage is
closely related to the swept angle. As for backward-swept blades, the
situation is the other way around. Additionally, the change of axial
excitation factor is more obvious. So the vibration reduction performance of
forward-swept blade is better.
Simultaneous Determination of Caffeine, Preservatives and Antioxidants in Energy- and Soft-Drinks Commercially Available in Bangladesh
Authors: Islam Md Samiul , Hossain Md Shahadat , Bhadra Subrata , Rouf Abu Shara Shamsur
Published: August 2016

This study describes a validated assay method to determine caffeine, benzoic acid, methylparaben, propylparaben, butylparaben, butylatedhydroxyanisole, and butylatedhydroxytoluene simultaneously by reversed phase high performance liquid chromatographic (HPLC) method. The separation of compounds was achieved on a C18 column in a gradient of acetonitrile and diluted sulfuric acid (pH=2.3) and quantification was performed by using a UV-detector set at 265 nm. The method was found to be linear over the concentration range of 60-90 ppm (R2=0.995), 200-300 ppm (R2=0.993), 16-24 ppm (R2=0.990), 16-24 ppm (R2=0.994), 16-24 ppm (R2=0.997), 48-72 ppm (R2=0.993), and 32-48 ppm (R2=0.994) for caffeine, benzoic acid, methylparaben, propylparaben, butylparaben, butylatedhydroxyanisole, and butylatedhydroxytoluene, respectively. Sixty energy- and soft-drink samples were analyzed where about 53% were found to contain caffeine among which 16% exceeded the tolerance limit (>200 ppm) set by USFDA. Moreover, 65% of analyzed samples contained benzoic acid and 10% of those samples exceeded the maximum allowable limit (>600 ppm) set by joint expert committee for food additives (JECFA).Dhaka Univ. J. Pharm. Sci. 15(1): 97-108, 2016 (June)
Metabolic Syndrome in Bangladeshi Menopausal Women
Authors: Jahan Muna Shalima , Billah Syed Muhammad Baqui
Published: August 2016

Objective: To assess the factors of metabolic syndrome (MetS) in post menopausal women in Bangladesh.Methods: Menopausal women are at increased risk of metabolic syndrome (MetS). This cross-sectional study on 64 willing post menopausal women from an urban and a rural area of Bangladesh was done. The socio-epidemiologic factors with anthropometric examination, blood pressure recording and fasting blood analysis for triglyceride (TG), high density lipoprotein (HDL), sugar were studied.Results: Prevalence of MetS was 50.0% (95% CI= 39.9%- 60.1%) among menopausal women, seventy five percent of them were urban. Low HDL cholesterol prevailed in almost 96% respondents followed by high TG (51%), obesity (28.0%), high fasting blood sugar (FBS, 27.1%) and hypertension (HTN, 16.9%). On logistic regression, age (OR=1.6, 95% CI: 1.3-1. 9), male sex (OR=2.5, 95% CI: 1.4-4.2) and exercise (OR=1.9, 95% CI: 1.2-2.9) produced significantly higher odds of being associated with MetS; rural area (OR=1.4, 95% CI: 1.0-2.1) and sedentary occupation (OR=1.7, 95% CI: 0.9-3.0) were associated just insignificantly. Though higher income, better education, good physical movement and knowledge of MetS produced protective odds, they were not significant.Conclusions: The study suggests that MetS is highly prevalent among Bangladeshi menopausal women. Further studies are needed to identify risk factors and for effective preventive measures to control this metabolic disease.J Bangladesh Coll Phys Surg 2016; 34(1): 15-20
Janeway Lesions in Systemic Lupus Erythematosus
Authors: Anam Ahmad Mursel , Shumy Farzana , Shareef Adnan , Rabbani Raihan
Published: August 2016

Abstract not availableJ Bangladesh Coll Phys Surg 2016; 34(1): 48-49
From the Desk of Editor in Chief 34(1)
Authors: Azad Khan Abul Kalam
Published: August 2016

Abstract not availableJ Bangladesh Coll Phys Surg 2016; 34(1): 52
Parametric Analysis of the Exergoeconomic Operation Costs, Environmental and Human Toxicity Indexes of the MF501F3 Gas Turbine
Authors: Torres-González Edgar , Lugo-Leyte Raul , Lugo-Méndez Helen , Salazar-Pereyra Martin , Torres-Aldaco Alejandro
Published: August 2016

This work presents an energetic, exergoeconomic, environmental, and toxicity analysis of the simple gas turbine M501F3 based on a parametric analysis of energetic (thermal efficiency, fuel and air flow rates, and specific work output), exergoeconomic (exergetic efficiency and exergoeconomic operation costs), environmental (global warming, smog formation, acid rain indexes), and human toxicity indexes, by taking the compressor pressure ratio and the turbine inlet temperature as the operating parameters. The aim of this paper is to provide an integral, systematic, and powerful diagnostic tool to establish possible operation and maintenance actions to improve the gas turbine’s exergoeconomic, environmental, and human toxicity indexes. Despite the continuous changes in the price of natural gas, the compressor, combustion chamber, and turbine always contribute 18.96%, 53.02%, and 28%, respectively, to the gas turbine’s exergoeconomic operation costs. The application of this methodology can be extended to other simple gas turbines using the pressure drops and isentropic efficiencies, among others, as the degradation parameters, as well as to other energetic systems, without loss of generality.
Quality of Life and Its Related Factors in Chinese Unemployed People: A Population-Based Cross-Sectional Study
Authors: Yang Xiaoshi , Yao Lutian , Wu Hui , Wang Yang , Liu Li , Wang Jiana , Wang Lie
Published: August 2016

With the global economic crisis and industrial restructuring, the unemployed are suffering from job loss-related stress and loss of income, which is believed to impair their mental and physical health, while coping and self-efficacy could combat the adverse effects of unemployment on health. Thus, this study aims to describe quality of life (QOL) among unemployed Chinese people and explore the associated factors. A cross-sectional study was conducted by convenience sampling, composed of 1825 unemployed people, from January 2011 to September 2011. Questionnaires pertaining to demographic characteristics, the 36-item Short-Form Health Survey (SF-36), the abbreviated version of the Cope Inventory (Brief COPE) and self-efficacy scales were used to collect information from unemployed people in the eastern, central, and western regions of China. Hierarchical multiple regression analysis was performed to explore the related factors of QOL. A structural equation model (SEM) was used to test the relations among coping, self-efficacy, and QOL. Mental QOL was significantly lower than physical QOL in Chinese unemployed people. Coping had significant effects on both physical component summary (PCS) and mental component summary (MCS), while self-efficacy played the mediating role in the association between Coping and QOL. Unemployed Chinese people’s mental QOL was disrupted more seriously than their physical QOL. An increase in coping could improve QOL by promoting better management of issues brought about by unemployment. In addition, self-efficacy has the ability to reduce the impact of unemployment on QOL, through the mediating path of coping on QOL. This study highlights the need of coping skills training and self-efficacy enhancement for better management of unemployment in order to improve QOL and well-being.
β-Ketoacyl-acyl Carrier Protein Synthase I (KASI) Plays Crucial Roles in the Plant Growth and Fatty Acids Synthesis in Tobacco
Authors: Yang Tianquan , Xu Ronghua , Chen Jianghua , Liu Aizhong
Published: August 2016

Fatty acids serve many functions in plants, but the effects of some key genes involved in fatty acids biosynthesis on plants growth and development are not well understood yet. To understand the functions of 3-ketoacyl-acyl-carrier protein synthase I (KASI) in tobacco, we isolated two KASI homologs, which we have designated NtKASI-1 and NtKASI-2. Expression analysis showed that these two KASI genes were transcribed constitutively in all tissues examined. Over-expression of NtKASI-1 in tobacco changed the fatty acid content in leaves, whereas over-expressed lines of NtKASI-2 exhibited distinct phenotypic features such as slightly variegated leaves and reduction of the fatty acid content in leaves, similar to the silencing plants of NtKASI-1 gene. Interestingly, the silencing of NtKASI-2 gene had no discernibly altered phenotypes compared to wild type. The double silencing plants of these two genes enhanced the phenotypic changes during vegetative and reproductive growth compared to wild type. These results uncovered that these two KASI genes had the partially functional redundancy, and that the KASI genes played a key role in regulating fatty acids synthesis and in mediating plant growth and development in tobacco.
Ultra Large Gene Families: A Matter of Adaptation or Genomic Parasites?
Authors: Schiffer Philipp , Gravemeyer Jan , Rauscher Martina , Wiehe Thomas
Published: August 2016

Gene duplication is an important mechanism of molecular evolution. It offers a fast track to modification, diversification, redundancy or rescue of gene function. However, duplication may also be neutral or (slightly) deleterious, and often ends in pseudo-geneisation. Here, we investigate the phylogenetic distribution of ultra large gene families on long and short evolutionary time scales. In particular, we focus on a family of NACHT-domain and leucine-rich-repeat-containing (NLR)-genes, which we previously found in large numbers to occupy one chromosome arm of the zebrafish genome. We were interested to see whether such a tight clustering is characteristic for ultra large gene families. Our data reconfirm that most gene family inflations are lineage-specific, but we can only identify very few gene clusters. Based on our observations we hypothesise that, beyond a certain size threshold, ultra large gene families continue to proliferate in a mechanism we term “run-away evolution”. This process might ultimately lead to the failure of genomic integrity and drive species to extinction.