bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluating the Accuracy of Spot Speed Data from Global Positioning Systems for Estimating Truck Travel Speed
Authors: Zhao Wenjuan , Goodchild Anne V. , McCormack Edward D.
Published: December 2011

A number of trucking companies use Global Positioning System (GPS) devices for fleet management. Data extracted from these devices can provide valuable traffic information such as spot (instantaneous) speeds and vehicle trajectory. However, the accuracy of GPS spot speeds has not been fully explored, and there is concern about their use for estimating truck travel speed. This concern was addressed by initially comparing GPS spot speeds with speeds estimated from dual-loop detectors. A simple speed estimation method based on GPS spot speeds was devised to estimate link travel speed, and that method was compared with space mean speed estimation based on GPS vehicle location and time data. The analysis demonstrated that aggregated GPS spot speeds generally matched loop detector speeds and captured travel conditions over time and space. Speed estimation based on GPS spot speeds was sufficiently accurate in comparison with space mean speeds, with a mean absolute difference of less than 6%. It is concluded that GPS spot speed data provide an alternative for measuring freight corridor performance and truck travel characteristics.
Effects of Turning Maneuvers and Route Choice on a Simple Network
Authors: Gayah Vikash V. , Daganzo Carlos F.
Published: December 2011

A simple symmetric network that consists of two tangent rings on which vehicles obey the kinematic wave theory of traffic flow and can switch rings at the point of tangency is studied. An online adaptive simulation reveals that if there is any turning whatsoever, the two-ring system becomes unevenly loaded for densities greater than the optimal density, and reduces traffic flow. Furthermore, the two-ring system jams at significantly lower densities than the maximum density possible.
Reaction Of Barley Genotypes To Bipolaris Sorokiniana
Authors: Rahman MM , Alam AKMM , Naher N , Sharifuzzaman SM , Uddin MAN
Published: December 2011

A study on response of 29 barley genotypes resistant to Bipolaris leaf blight (Bipolaris sorokiniana) was conducted to investigate the relationship of the components of resistance of 29 barley genotypes. Data on five components of resistance viz., infection frequency (number of lesions per plant), lesion size (mm2), percent leaf area affected by lesion, percent necrotic area on leaf, and disease severity were recorded as components of resistance. The genotypes fall into four clusters. Cluster I was to be the largest having 11 genotypes which was followed by cluster III, IV, and II. Considering the overall mean performances of different clusters, genotypes of cluster II showed better performance against resistance. From the cannonical variate analysis, it was found that three components like lesion size, necrosis, and 100-seed weight were found positive for the both vector, and these characters contributed maximum towards the divergence for disease development of the barley accessions.   Keywords: Bipolaris sorokiniana; barley; leaf blight DOI: http://dx.doi.org/10.3329/bjar.v36i1.9236 BJAR 2011; 36(1): 123-128
Uptake Of Different Nutrient Elements By Legume Crops In Wheat -Legume- T. Aman Cropping Pattern
Authors: Sarker MJU , Siddiky MA , Jahiruddin M , Mian MH , Islam MS
Published: December 2011

A study on nutrient uptake by different legume crops was carried out at two locations–one at Bangladesh Agricultural University farm Mymensingh and another at Regional Agricultural Research Station of Bangladesh Agricultural Research Institute, Jamalpur. The objective was to find out the optimum concentrations of different nutrient elements and its uptake by legume crops in a Wheat-Legume-T. Aman cropping pattern. The uptake of different elements was markedly varied by legume crops at both the locations in two consecutive years of the study. It was also noticed that cowpea removed the highest quantity of nutrient elements from the soils in the treated plots compared to mungbean and blackgram. Besides, stover received the maximum contents of potassium followed by nitrogen, phosphorus, and sulphur which was significantly different over legume seeds. Keywords: Nutrient uptake; legume crops. DOI: http://dx.doi.org/10.3329/bjar.v36i2.9251 BJAR 2011; 36(2): 247-253
Effect Of Sowing Time And Plant Spacing On The Yield And Yield Attributes Of Sweet Pepper (Capsicum Annuum)
Authors: Alam MS , Saha SR , Salam MA , Alam MS , Alam MK
Published: December 2011

An experiment was carried out at the Olericulture field of Horticulture Research Centre of BARJ, Joydebpur, Gazipur during September 2006 to April 2007 to investigate yield and yield attributes of sweet pepper as influenced by plant spacing and sowing time. There were altogether 21 treatments comprising seven sowing dates viz. 1 September, 15 September, 1 October, 15 October, 30 October, 15 November, 30 November and three spacings viz. 50 × 50 cm, 50x40 cm, and 50 × 30 cm. The experiment was laid out in a Randomized Complete Block Design (factorial) with three replications. The results of the experiment showed that majority of the yield and yield components significantly varied with variation of spacing and sowing time. Only number of fruits per plant and fruit yield per plant resulted significantly higher which reflected higher yield for 1 October sowing. The number of branches per plant, number of fruits per plant, fruit length, individual fruit weight, yield per plant were found significantly increased with the increasing plant spacings but other parameters were found to be significantly increased with the decreasing plant spacing. The combined effect of sowing date and plant spacing also had significant effect on different growth and yield parameters and yield. The highest yield (19.36 t/ha) of fruit was recorded from the earlier sowing (1 October) with the closest spacing (50 × 30 cm). But reasonable yield could be obtained up to 30 October with same spacing. Keywords: Sowing time and plant spacing; yield and yield attributes; sweet pepper. DOI: http://dx.doi.org/10.3329/bjar.v36i2.9254 BJAR 2011; 36(2): 271-278
Effects Of Organic And Inorganic Sources Of K On Rice Yield And Soil K Balance In The Rice-Rice Cropping System
Authors: Saha PK , Akter M , Miah MAM , Zaman SK
Published: December 2011

Field experiments were conducted through T. Aman 2003–Boro 2008 at the Bangladesh Rice Research Institute (BRRI), Gazipur Farm with a view to determining the appropriate dose of K fertilizer in soils under double rice cropping system and to find out the alternative source of K for wet land rice cultivation. Four levels of inorganic K (0, 33, 50 & 66 kg K/ha and farmers’ practice from MoP) and one recycling of rice straw 4.5 t/ha (dry basis) were tested. Incorporation of rice straw into soil contributed significantly to grain yield in successive growing seasons comparable with inorganic K fertilizer. In clay- loam soil, K at the rate of 50 kg K/ha should be applied to obtain the maximum yield in both T. Aman and Boro rice seasons. Rice straw may be a potential alternative source of K for sustaining soil K fertility and maximizing rice yield. Agronomic use efficiency of K decreased with increasing K levels. A narrower balance of K was observed when rice straw or a higher dose of inorganic K fertilizer was used. Keywords: K; rice yield; soil K balance; rice straw. DOI: http://dx.doi.org/10.3329/bjar.v36i2.9258 BJAR 2011; 36(2): 305-311
Impact Of Micro-Finance On The Development Of Stree Shakti Group Members
Authors: Bhavya KV Sylvia , Umesh KB
Published: December 2011

Micro- finance helps the rural poor to improve their living standards and fulfill their credit needs. Stree Shakti Groups (SSGs) are new innovation in the field of rural economic development, to finance the rural women and also to satisfy their credit needs. This study mainly focuses on the impact of micro-finance on the development of SSG members. The study was undertaken in Doddaballapura taluk of Bangalore rural district of Karnataka state, India and the required data were collected from 100 SSG members and 30 non-SSG members. It was found that the number of income generating activities taken up by SSG members (five) was higher compared to non-SSG members (three) and the income generated from these activities was also higher compared to non-SSG members. There was significant growth in the amount of loan borrowed, repayment and savings over time among SSG members. SSG finance substantially enhanced employment opportunities for members compared to non-members, which led to improved income and living standard of members. Since SSGs play a major role in the development of women, there is a need to encourage more number of SSGs. The study also reveals that the performance of Non Governmental Organization (NGO) promoted SSGs was much better than Government promoted SSGs. Hence, more number of NGOs must be involved in promoting SSGs covering more womenfolk. Keywords: Micro-finance; Stree Shakti group; self help group; impact; empowerment; non-governmental organization DOI: http://dx.doi.org/10.3329/bjar.v36i2.9261 BJAR 2011; 36(2): 333-350
Adoption of PBL to Online Environments
Authors: Gursul Fatih , Keser Hafize , Gulsecen Sevinc
Published: December 2011

This study’s aim is to find out student’s perspectives on online and face-to-face problem-based learning approaches. The study was conducted at the Department of Computer Education and Instructional Technologies, Faculty of Education, Hacettepe University. Participants were 42 freshman students attending the department during fall of 2006-2007. These students were put into two groups—the online problem-based learning group and the face-to-face problem-based learning group. The research was conducted on Mathematics-I while implementing the topic of ‘derivation’. The content analysis statistical technique is used, as well as a questionnaire consisting of open-ended questions, which perform as a data collection tool to find out the views of the students in context to the process.
E-Assessment as a Driver for Cultural Change in Network-Centric Learning
Authors: Eijkman Henk , Herrmann Allan , Savige Kathy
Published: December 2011

This paper explores the potentially powerful role e-assessment practices can have on culture change in learning and teaching. This paper demonstrates how new e-assessment practices can ‘push back’ through educational institutions. This is done by applying the work of Gibbs and Simpson (2004/5) to e-assessment practices. To illustrate the practical effects of this evidence-based framework, the authors use UNSW@ADFA to demonstrate the possibilities for new e-assessment practices and their potential to drive systemic change. The authors conclude that the incorporation of these structured, evidence-based e-assessment practices demonstrably improve learning outcomes and student engagement without increasing the workload of staff and students.
A Semantic-Driven Adaptive Architecture for Large Scale P2P Networks
Authors: Eftychiou Athena , Vrusias Bogdan , Antonopoulos Nick
Published: December 2011

The increasing amount of online information demands effective, scalable, and accurate mechanisms to manage and search this information. Distributed semantic-enabled architectures, which enforce semantic web technologies for resource discovery, could satisfy these requirements. In this paper, a semantic-driven adaptive architecture is presented, which improves existing resource discovery processes. The P2P network is organised in a two-layered super-peer architecture. The network formation of super-peers is a conceptual representation of the network’s knowledge, shaped from the information provided by the nodes using collective intelligence methods. The authors focus on the creation of a dynamic hierarchical semantic-driven P2P topology using the network’s collective intelligence. The unmanageable amounts of data are transformed into a repository of semantic knowledge, transforming the network into an ontology of conceptually related entities of information collected from the resources located by peers. Appropriate experiments have been undertaken through a case study by simulating the proposed architecture and evaluating results.
One Anchor Distance and Angle Based Multi - Hop Adaptive Iterative Localization Algorithm for Wireless Sensor Networks
Authors: Kotwal S. B. , Verma Shekhar , Tomar G. S. , Abrol R. K.
Published: December 2011

This paper presents distance and angle measurements based Multi-Hop Adaptive and Iterative Localization algorithm for localization of unknown nodes in wireless sensor networks (WSNs). The present work determines uncertainty region of unknown nodes with respect to known (anchor) nodes using noisy distance and angle measurements. This node transmits its uncertainty region to other unknown nodes to help them determine their uncertainty region. Because of noisy distance and angle measurements, the error propagation increases the size of regions of nodes in subsequent hops. Using only one anchor node as reference, the proposed iterative localization algorithm reduces the error propagation of this noisy distance and angle measurements and the uncertainty region of all unknown nodes within a given communication range. The results clearly indicate the improved efficiency of the proposed algorithm in comparison with existing algorithms.
Social Media vs. the Public Sector
Authors: Fyfe Toby , Crookall Paul
Published: December 2011

What happens when the forces of social media—collaboration, open information, participation—collide with the entrenched patterns of public sector bureaucracy such as public servant anonymity, information hoarding, risk aversion, privacy, secrecy, and organizational silos? Different public service organizations, subject to the same rules, vary widely in response: from engagement to acceptance to resistance. This chapter provides a selective survey of the literature and some guidance for those who want to fast-track social media in the public sector.
Measuring the Impact of Social Media use in the Public Sector
Authors: Mergel Inez
Published: December 2011

Existing research on eGovernment performance has provided limited proof for the impact the use of technology has on citizen participation, engagement or generally satisfaction with government activities. Social media applications have the potential to improve responsiveness, reach, and efficiency, and even cost savings in government. The current Government 2.0 initiatives launched by all executive departments and agencies of the U.S. Federal Government as a response to President Obama’s Transparency and Open Government memo show that government agencies are implementing social media applications as additional information and communication channels. This chapter provides a comparison between traditional eGovernment measurement techniques and the current practices, highlighting the current practices of measuring social media impact in the public sector. The insights are based on data collected in 2010 from interviews with social media directors in the most innovative executive departments and agencies. The results show that the current standard practices mostly include quantitative impact measures instead of the qualitative measures needed to better understand the sentiments of citizens.
Local Governments and Social Networking
Authors: Merwin Gerald A. , McDonald J. Scott , Merwin Keith A. , McDonald Maureen , Bennett John R.
Published: December 2011

This chapter argues that Web 2.0, a valuable tool used to expand government-citizen communication opportunities and bring citizens as a group closer to government, widens a communication opportunity divide between local government and its citizens. Web 2.0 access is almost exclusively English-language based, benefiting that segment of the population and leaving others behind, especially the fastest growing language minority, Spanish speakers. While local governments continue to take advantage of the ability to interact with citizens through social networking (Aikins, 2009; Vogel, 2009), McDonald, Merwin, Merwin, Morris, & Brannen (2010) found a majority of counties with significant populations of citizens with Limited English Proficiency (LEP) did not provide for the translation needs of these citizens on their Websites. The chapter finds that Web 2.0-based communication is almost exclusively in English and that cities are missing opportunities to communicate. It concludes with recommendations based on observations of communities employing Web 2.0 to engage non-English speaking populations.
Assessment of Web 2.0 Applications Employed by Human Resource Departments in U.S. Cities
Authors: McDonald Maureen , McDonald J. Scott , Merwin Gerald A. , Merwin Keith A. , Richardson Mathew
Published: December 2011

Most local governments employ an intranet within the organization, to assist in human resources. A telephone survey of local government officials (n=17) found these intranet sites employ few Web 2.0 applications. The survey found most cities have plans to increase their use of Web 2.0 applications for human resources management. However, the recent economic recession has adversely impacted these plans. The chapter forwards recommendations to improve local governments’ use of Web 2.0 applications while maintaining cost efficiencies.
Authentic Learning in Online Courses
Authors: Gearhart Deb
Published: December 2011

The purpose of this chapter is to describe authentic learning, review the literature pertaining to authentic learning, discuss the benefits for online learning, and provide a model for the use of authentic learning in online course design. Students comment they are motivated by solving real-world problems and often express a preference for doing rather than listening. At the same time, most educators consider learning by doing the most effective way to teach (Lombardi, 2007). The chapter will be beneficial to instructors and instructional designers alike.
A Distributed Secure Architecture for Vehicular Ad Hoc Networks
Authors: Gazdar Tahani , Belghith Abdelfettah , Benslimane Abderrahim
Published: December 2011

In this paper, the authors propose a dynamic Public Key Infrastructure (PKI) for vehicular ad hoc networks to distribute the role of the central certification authority (CA) among a set of dynamically elected CAs. The election process is based on a clustering algorithm relying on trust levels and relative mobility. Furthermore, the authors have adapted the Dynamic Demilitarized Zones to protect the elected CAs from malicious nodes and enable them to act as registration authorities (RA). Extensive simulations are conducted to evaluate the performance of the clustering algorithm and investigate the impact of the vehicle speed, the vehicle average arrival rate, and the percentage of confident vehicles on the stability and efficiency of the security infrastructure. The authors demonstrate the percentage of confident nodes has a little impact on these performance metrics and that the minimum number of CAs to cover the entire platoon.
Web-Based Instruction
Authors: Lin Cheng-Yao , Luo Fenqjen , Lo Jane-Jane
Published: December 2011

This case study explored the efficacy of web-based instruction on preservice elementary teachers’ mathematics learning. Web-based instruction is appealing to many schools in urban settings because it helps them to face the two big challenges most akin to their schools: to motivate students’ interests and to meet the diverse students needs with its interactive feature and adaptive capability. Ten preservice elementary teachers were interviewed regarding their ability to model and reason with fractions after receiving web-based instruction on these topics in their regular mathematics method course. The interview transcripts were used to provide information about the strength and weakness of participants’ conceptual and procedural understanding of fractions. The findings of this case study identify promises and challenges in supporting the recommendations of many national reports, such as the NCTM Professional Standards for School Mathematics (2000) and the National Mathematics Advisory Panel (2008), in incorporating technology into the compulsory mathematics classrooms.
Designing District-Wide Technology-Rich Professional Development
Authors: Polly Drew , Mims Clif , McCombs Brenda
Published: December 2011

This case will focus on the following situation: As the technology coordinator for a school district you receive a state grant to provide technology resources and professional development for every teacher in the intermediate (Grades 5-6), middle (Grades 7-8) and high school (Grades 9-12) classrooms in your district. Your superintendent and school board have asked you to: design differentiated professional development to meet all teachers’ needs; include some outside consultants but quickly build teacher capacity so future professional development can be facilitated by district employees; provide educational materials for teachers and parents about internet safety and legal issues; determine that the use of technology has positively impacted student learning outcomes. This case study describes the story of how one school district responded to this challenge.
Strategic Issues of Supply Chain Design and Management
Authors: Heidari Nooshin , Rezapour Shabnam
Published: December 2011

A supply chain (SC) is composed of different facilities and also their definite roles with the aim of delivering goods or services to the customer in an effective way. Obviously the physical structure of each SC has an important role in its performance. In this chapter, the authors aim to describe SC network (SCN) design definition, classification and related issues to this subject, models and solution methods. At the end, the conclusion is provided.
The Design of Hovercraft to Support Offshore Operations in the Beaufort and Chukchi Seas
Authors: Gifford John H. , Cox Malcolm J. , Barton Robert H.
Published: December 2011

Griffon Hoverwork Ltd (GHL) was commissioned by Shell in 2009 to complete concept designs of fit for purpose hovercraft capable of conducting year round activities, from shore to 15 nautical miles offshore in the Beaufort Sea and further offshore in the Chukchi Sea. This required that the designs have the capability to operate in extreme cold conditions (-40°C) and have the ability to cross ice ridges of significant height.

The operation calls for three distinct types of hovercraft:A Routine Re-supply craft capable of carrying 30 tonne of cargo or passenger modules.A Hoverbarge capable of carrying a payload of 150 tonne.An Escape, Evacuation, Rescue (EER) craft for evacuating the rig in case of fire or other emergencies, to be positioned on the rig.

Application.

Previous work for Shell by D.F. Dickins Associates, had shown that the hovercraft may offer logistics options and a secondary solution to the problem of emergency evacuation of installations off the North Slope of Alaska.

Results, Observations and Conclusions.

As starting points, Shell provided outline concepts for two logistics craft. For the EER role, GHL have two examples of commercially available hovercraft designs that have been tried and tested in service, namely the Griffon 8100 and the BHT150. It has been reasoned that the 8100TD cannot be designed with any greater cushion height than 2.5m and the BHT150 no greater than 3.0m. Part of the requirement was to take as much research information as possible from cold weather hovercraft operations and then, using a many proven components as practical, develop the concepts. A ridge crossing formula was developed to model the capabilities of the craft and determine the ridge approach speed. From the outset, it was relised that existing craft would require extensive modifications, particularly to the skirt in order to increase the cushion clearance for operations over rough ice and potentially high sea states. This in turn required the craft to be increased in width to maintain stable operation.

The paper will show how the solutions were developed, how the key obstacles were overcome, and will explain how further research is being undertaken.

Significance of Subject Matter.

This paper describes how appropriately designed hovercraft can provide important solutions for some of the logistics and emergency evacuation problems that are foreseen for the oil industry operating offshore in the Arctic.
ARKTOS Shear Zone Evacuation Craft Design Development
Authors: Hall T.A. , Seligman B.H.J.W.
Published: December 2011

The ARKTOS Evacuation Craft has been the primary means of emergency evacuation on Arctic and Caspian Sea bottom founded oil exploration and production facilities for over 20 years.

Oil production strategies are currently being developed by major oil companies beyond the Beaufort Sea Shear Zone, where the polar pack and landfast ice meet. The Shear Zone is formed by the moving polar ice pack shearing against the inshore ice that is held fast to the coastal seabed and the shore. Large, irregular ice features can be formed as a result of the shearing action as well as open leads with vertical ice freeboards.

A major area of concern for any development within and beyond the Shear Zone is Escape, Evacuation, and Rescue (EER) capability, due to the extreme environmental conditions that will be encountered. In response to a major oil company initiative, a conceptual design for a 75 person ARKTOS Amphibious Evacuation Craft suitable for operation in this region has been developed.

This paper describes continuing development of the ARKTOS Shear Zone Craft design, including the affect on performance in ice of increased Craft track width, extended track carriages, increased water jet thrust and hydrostatic drives in combination with inching mode. Also covered are self-righting capability and davit launching from a production platform onto ice or into open water.

Introduction

Existing offshore oil developments on the North Slope of Alaska are situated on natural or manmade gravel islands that are located within the Landfast Ice Zone. The Landfast Ice Zone extends between the coastline and the barrier islands and up to a few thousand feet beyond. ARKTOS Craft have been used for crew evacuation on all of these installations to date and are typically parked near the edge of the islands, and should an evacuation be necessary, are simply driven away from the island over the land-fast ice, through open water or broken ice/water mixture (Figure 1).

With the push to explore and develop Beaufort Sea oilfields further offshore within the Shear Zone and the Pack Ice Zone, gravity based or large floating offshore structures will be required. Personnel evacuation systems for these structures will face even more extreme conditions than the evacuation craft on existing U.S. Beaufort Sea offshore structures such as heavier sea states and mobile ice floes with substantial ice features.
U.S. Geological Survey Circum-Arctic Resource Appraisal
Authors: Gautier Donald L.
Published: December 2011

Among the greatest uncertainties in future energy supply is the amount of oil and gas yet to be found in the Arctic. Using a probabilistic geology-based methodology, the U.S. Geological Survey has assessed the area north of the Arctic Circle. The Circum-Arctic Resource Appraisal (CARA) consists of three parts:Mapping the sedimentary sequences of the Arctic (Grantz and others 2009),Geologically based estimation of undiscovered technically recoverable petroleum (Gautier and others 2009, discussed in this presentation) andEconomic appraisal of the cost of delivering the undiscovered resources to major markets (also reported at this conference by White and others).

We estimate that about 30% of the world's undiscovered gas and about 13% of the world's undiscovered oil may be present in the Arctic, mostly offshore under less than 500m of water. Billion BOE-plus accumulations of gas and oil are predicted at a 50% probability in the Kara Sea, Barents Sea, offshore East and West Greenland, Canada, and Alaska. On a BOE basis, undiscovered natural gas is three times more abundant than oil in the Arctic and is concentrated in Russian territory. Oil resources, while critically important to the interests of Arctic countries, are probably not sufficient to significantly shift the current geographic patterns of world oil production.

Introduction

The U.S. Geological Survey (USGS) has completed an assessment of the yet-to-find, technically recoverable petroleum in the Arctic. The Circum-Arctic Resource Appraisal (CARA) provides probabilistic estimates of the numbers, sizes, and aggregate volumes of oil, gas, and natural gas liquids in undiscovered accumulations (Gautier et al. 2009). Most discoveries will probably be made on the continental shelves, under less than 500 meters of water.

The CARA is a geologically study of the potential for new discoveries of conventional oil and/or gas in accumulations larger than 50 million barrels of oil or 300 billion cubic feet of natural gas north of the Arctic Circle. So-called unconventional resources such as coal bed methane, heavy oil and bitumen, and gas hydrates were not included in the study.

Before the assessment could be conducted, it was necessary to compile a consistent map of the sedimentary basins of the Arctic, delineated according to geologic age, tectonic history, thickness of sedimentary strata, and structural style (Grantz et al. 2009). Using the new map, the Arctic was subdivided into 69 geologically defined subsets called Assessment Units (AUs); the AU boundaries are available as digital shape files online (USGS 2009).
Resource Appraisal Technology for Undiscovered Arctic Petroleum
Authors: White L.P. Red , Verma Mahendra , Gautier Don
Published: December 2011

The Circum-Arctic Resource Appraisal (CARA) comprises three components:a geological map of Arctic sedimentary basins published by Grantz and others in 2009,a geologically based assessment of undiscovered technically recoverable resources published by Gautier and others in 2009, andan economic appraisal of the cost of delivering the undiscovered oil and gas resources to major markets.

This third component - the economic appraisal of the technically recoverable resources assessed by the CARA - is presented here for the first time in North America.

The economic appraisal consists of a prototype technology that augments the CARA assessment of technically recoverable resources with the addition of an economic benchmark. Our approach to this appraisal is to integrate the results of six separate technical efforts:the geologically based assessment of undiscovered technically recoverable resources,an empirically based statistical model of well flow rates,an experimental design model,a field development, production, and transportation model,a statistical cost estimation mode, anda hypothetical transportation system connecting the Arctic petroleum Provinces to major markets in the northern hemisphere.

The results of these six models are integrated in a Monte Carlo simulation of potential oil and gas accumulations for each CARA assessment unit (AU). Key parameters such as the number of fields, their volumes, well productivities, water depths, drilling depths, and distances from shore are simulated for each field in each AU. Exploration, development, production and transportation costs for each field and AU are estimated and then aggregated. The Monte Carlo simulation generates resource cost-volume curves for each AU and Province, displaying the probability range of volumes of oil or gas available to major markets as a function of unit cost. These Province curves are aggregated to a Circum-Arctic total.

The USGS is seeking collaborative relationships in the research and development of technology for the economic appraisal of undiscovered resources.
Overview of Case Studies for Draft ISO 19906
Authors: Thomas Graham A.N. , Masterson Dan , Spring Walt
Published: December 2011

The new international code ISO 19906 "Petroleum and natural gas industries - Arctic offshore structures" [1] was published in December 2010 after more than nine years of development, see Spring et al. [2]. Under the ISO process for standards development, ISO/DIS 19906 (the draft for public comment) was published in January 2009 and distributed to all ISO member countries for review and comment by June 2009. During this five-month period the opportunity was taken to perform case studies to ensure that the provisions of the code and its references were sufficiently complete for an experienced and knowledgeable engineer to design the structures within its scope. The objectives were to identify errors and gaps, ensure that diverse structures were adequately addressed, and to collate comments to the ISO draft for consideration by the Technical Panels with delegated responsibility for the provisions as they prepared the Final Draft. This paper sets out the case studies performed and the improvements arising in the final document resulting from comments provided by the organisations performing the case studies.

Introduction

The new ISO 19906 has been developed in Working Group 8 (WG8) of ISO Technical committee TC67/SC7 "Offshore structures". Experts from all arctic nations and from most other nations involved in the design of offshore structures in arctic and cold regions participated in WG8. Consequently, all the arctic nations and all European nations have undertaken to adopt ISO 19906 into their sets of national standards, and ISO 19906 is expected to be adopted worldwide for design of arctic offshore structures. WG8 and its supporting industry therefore decided to initiate a programme of case studies both to validate the standard and to start the process of industry engagement.

WG8 established TP10 "Case studies and calibration" in June 2008 to execute a calibration study and to perform case studies on ISO/DIS 19906. The members were volunteers from around the world, many from the oil and gas companies who would be future owners and operators of arctic offshore structures..

TP10 defined eight cases for study. Each case was for a specific structure type in a specified arctic region, with key parameters defined but otherwise it was left to the performer of the study to bring their experience and knowledge to complete the scenario. Proposals were sought from organizations around the world, including consultants, design contractors, universities, research institutes and classification societies. Forty seven offers were received, from North America, Europe and Russia, of which fifteen were contracted using industry funding and one was offered at no cost TP10 held five meetings and corresponded extensively by email and telephone conference calls. The OGP (the International Association of Oil and Gas Producers) facilitated funding from oil companies participating in WG8 and TP10 to fund TP10's activity. The OGP also acted as the administrator for the contracts required to execute the work directed by TP10.
Approach to Performance, Operability and Risk Assessment of the Shtokman Floating Platform in Ice
Authors: Liferov Pavel , Le Marechal Guillaume , Albertini Marc-Marie , Metge Michel , ter Brake Erik
Published: December 2011

The Shtokman Gas Condensate Field (SGCF) is located 610 km from Murmansk in the Barents Sea. The water depth at location is around 340 m. The offshore facilities of the SGCF Phase 1 development will include ice-resistant ship shape disconnectable turret moored floating platform (FP). Significant sea ice invasions occur at Shtokman in approximately 3 out of 10 years, on average. Icebergs may also occur in the SCGF area. Ice and iceberg management are planned to support the FP operations. The present paper describes the methodology to assess performance, operability and risk of the FP in waters where occasional invasion of sea and glacial ice is anticipated.

Introduction

Challenges with ice-related design and operating philosophy for the Shtokman FP have been described in [Ref. 1]. In brief, the main challenge is to achieve an appropriate reliability level and at the same time minimize operational downtime at acceptable costs. Table 1 summarizes the main ice-related challenges as identified in the pre-FEED and updated during the FEED, categorized by the accidental scenarios.

Actions have been taken in order to address the challenges and quantitatively assess the risks. It shall be emphasised that no attempt was made to target the design of individual components to achieve the target reliability level for the entire system, i.e. floating platform with respect to ice actions. This is simply because it would have been too speculative given all the uncertainties involved. On the contrary, it was decided early to establish challenging but realistic design targets for the main systems (e.g. hull, mooring and disconnection system) and in parallel, work on design of the operational measures, including assessment of their efficiency and reliability. Further, quantitative operability and risk assessments of the entire system have been performed to evaluate potential needs for optimisation.

The objective of this paper is to present the approach developed and used for assessing performance, operability and risk of the Shtokman Floating Platform with regard to sea and glacial ice. The content of this paper is based on numerous studies performed to provide input for the Final Investment Decision.
Reliability of Power Supply in Remote BGV/RGV Stations Along the Pipeline, a Key Factor for Arctic Pipelines Operation
Authors: Gropper Jean
Published: December 2011

1. INTRODUCTION

One of the most serious problems in strategic pipeline projects is the need for reliable power for unattended stations in the severe environments under which these pipelines must continuously operate (temperatures as low as −55°C (−67°F) in winter, roads to the stations inaccessible for long periods of time making the stations inaccessible for maintenance crews, etc).

The objectives for high reliability in RGV operation, telecommunications, cathodic protection and SCADA systems in strategic projects have become staggering. In areas not serviced by commercial power, the problems faced by the power systems designers are very stringent since power generators must operate continuously on a 24 hour-per-day basis 365 days per-year.

The high reliability of the power supply in remote stations along the pipeline can be achieved by:–Selection of the most reliable remote power generators–Providing adequate redundancy of power generators

Telecommunications, SCADA, cathodic protection facilities along oil and gas pipelines are mission-critical, carrying vital performance, telemetry and control data.

The use of specially designed, arctic type, Closed Cycle Vapor Turbogenerators and their associated non-electric heating systems in arctic telecommunication systems has solved two of the most stringent problems of the pipeline operators: reliable remote power up to 4 kW is provided with maintenance requirements reduced to a visit only once in 6 months or more, and required temperature ranges in equipment shelters are maintained, assuring correct operation of the sensitive electronics, without any need of electrical power.

This paper reviews the key criteria to consider in selecting power solutions for remote site applications and CCVT performance is reviewed. The paper goes on to present case histories, including the Alaska pipeline, that demonstrate the field reliability and performance of CCVTs over the last thirty five years.

2. CRITERIA FOR SELECTING POWER SOLUTIONS FOR REMOTE SITES

There are a number of critical parameters which must be assessed when selecting a power solution for a network or a specific remote site.

Reliability.

Because these critical remote sites are difficult (and expensive) to reach - or are inaccessible for part of the year, reliable operation is extremely important. Reliability is typically measured in terms of Mean Time Between Failure (MTBF). CCVT technology has a proven performance history, demonstrating over 200,000 hours MTBF for the turbine and 30,000 hours MTBF for the entire system. These data are based on thirty seven years of field experience.
Cathodic Protection Design Considerations for Offshore Structures in the Arctic Environment
Authors: Weldon Clark P.
Published: December 2011

The Arctic imposes unique challenges for design of cathodic protection (CP) systems for offshore structures. These include alternative structure designs, and environmental factors such as pack ice, high water resistivity, extreme tidal velocities and amplitudes, and severe weather. Traditional approaches to CP design for offshore structures are typically not suitable for service in Arctic conditions. Adaptations include almost exclusive use of impressed current or hybrid CP systems, versus traditional sacrificial anode designs, specialized anode deployment and cabling systems, and design of CP monitoring equipment suitable for Arctic conditions.

The effect of Arctic conditions on CP current requirement, anode current output, anode material selection, anode configuration, cabling systems and power supplies is discussed. Case histories of specialized CP designs for offshore structures in the Russian Arctic and Cook Inlet are presented. These case histories include relevant CP design, construction, installation and operating details.

Introduction

Cathodic protection using distributed weld-on aluminum alloy anodes has become the offshore industry standard for corrosion control on immersed surfaces of offshore structures in most oil producing areas of the world. Aluminum anodes with a design life equal to the expected service life of the platform are welded to the structure in the fabrication yard. Use of coatings is typically limited to the splash zone areas and the inside of ballast tanks on floating structures. These stand-alone sacrificial anode systems are essentially maintenance free, except in the rare instances where anode retrofit is required to extend the platform service life. The use of impressed current cathodic protection (ICCP) systems is generally limited to floating vessels such as FPSOs or drill ships, and for anode retrofit.

With respect to cathodic protection design, offshore structures located in Arctic/subArctic regions subject to the presence of sea ice, frigid temperatures and other extreme environmental conditions often require a different approach. The demands of the Arctic environment impact cathodic protection design in two general ways - electrochemically and mechanically. Electrochemical impacts include, but are not limited to, increased current requirement, higher seawater resistivity, reduced anode performance and higher rectifier voltage requirements. Mechanical affects are considered those that impact the design of cathodic protection hardware with respect to resistance to physical damage. These include the damage from ice impact and/or abrasion, freezing and wave/current forces. In some cases, mechanical and electrochemical effects are combined, as in the mechanical removal of calcareous deposits by ice or wave action, which increases current requirement.
Total depletion of ozone reached in the 2010–2011 Arctic winter as observed by MIPAS/ENVISAT using a 2-D tomographic approach
Authors: Arnone E. , Castelli E. , Papandrea E. , Carlotti M. , Dinelli B. M.
Published: December 2011

Abstract. We present observations of the 2010–2011 Arctic winter stratosphere from the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) onboard ENVISAT. Limb sounding infrared measurements were taken by MIPAS during the Northern polar winter and into the subsequent spring, giving a continuous vertically resolved view of the Arctic dynamics, chemistry and polar stratospheric clouds (PSCs). We adopted a 2-D tomographic retrieval approach to account for the strong horizontal inhomogeneity of the atmosphere present under vortex conditions, self-consistently comparing 2011 to the 2-D analysis of 2003–2010. Unlike most Arctic winters, 2011 was characterized by a strong stratospheric vortex lasting until early April. Lower stratospheric temperatures persistently remained below the threshold for PSC formation, extending the PSC season up to mid-March, resulting in significant chlorine activation leading to ozone destruction. Through inspection of MIPAS spectra, 84% of PSCs were identified as supercooled ternary solution (STS) or STS mixed with nitric acid trihydrate (NAT), 16% formed mostly by NAT particles, and only a few by ice. In the lower stratosphere at potential temperature 450 K, vortex average ozone showed a daily depletion rate reaching 100 ppbv day−1. In early April at 18 km altitude, 10% of vortex measurements displayed total depletion of ozone, and vortex average values dropped to 0.6 ppmv. This corresponds to a chemical loss from early winter greater than 80%. Ozone loss was accompanied by activation of ClO, associated depletion of its reservoir ClONO2, and significant denitrification, which further delayed the recovery of ozone in spring. Sporadic increases of NO2 associated with evaporation of sedimenting PSCs were also observed. Once the PSC season halted, ClO was reconverted into ClONO2. Compared to MIPAS observed 2003–2010 Arctic average values, the 2010–2011 vortex in late winter had 15 K lower temperatures, 40% lower HNO3 and 50% lower ozone, reaching the largest ozone depletion ever observed in the Arctic. The overall picture of this Arctic winter was remarkably closer to conditions typically found in the Antarctic vortex than ever observed before.
Linear estimation of particle bulk parameters from multi-wavelength lidar measurements
Authors: Veselovskii I. , Dubovik O. , Kolgotin A. , Korenskiy M. , Whiteman D. N. , Allakhverdiev K. , Huseyinoglu F.
Published: December 2011

Abstract. An algorithm for linear estimation of aerosol bulk properties such as particle volume, effective radius and complex refractive index from multiwavelength lidar measurements is presented. The approach uses the fact that the total aerosol concentration can well be approximated as a linear combination of aerosol characteristics measured by multi-wavelength lidar. Therefore, the aerosol concentration can be estimated from lidar measurements without the need to derive the size distribution, which entails more sophisticated procedures. The definition of the coefficients required for the linear estimates is based on an expansion of the particle size distribution in terms of the measurement kernels. Once the coefficients are established, the approach permits fast retrieval of aerosol bulk properties when compared with the full regularization technique. In addition, the straightforward estimation of bulk properties stabilizes the inversion making it more resistant to noise in the optical data. Numerical tests demonstrate that for data sets containing three aerosol backscattering and two extinction coefficients (so called 3β+2α) the uncertainties in the retrieval of particle volume and surface area are below 45% when input data random uncertainties are below 20%. Moreover, using linear estimates allows reliable retrievals even when the number of input data is reduced. To validate the approach, the results obtained using this new technique are compared with those based on the previously developed full inversion scheme that relies on the regularization procedure. Both techniques were applied to the data measured by multiwavelength lidar at NASA/GSFC. The results obtained with both techniques using the same observations are in good agreement. At the same time, the high speed of the retrieval using linear estimates makes the method preferable for generating aerosol information from extended lidar observations. To demonstrate the efficiency of the method, an extended time series of observations acquired in Turkey in May 2010 was processed using the new technique permitting, for what we believe to be the first time, temporal-height distributions of particle parameters.
Book Review: Cross-Border Partnerships in Higher Education: Strategies and Issues
Authors: Gök Enes
Published: December 2011

None.