bluuebunny/crossref_metadata_2025 huggingface dataset:
Using a New Intelligent Completion Strategy to Increase Thermal EOR Recoveries–SAGD Field Trial
Authors: Shaw Joel , Bedry Mark
Published: December 2011

A completions strategy has been developed for improving both steam injection and production conformance in a thermal- enhanced oil recovery (EOR) project by using intelligent completion technology that incorporates interval control valves (ICVs), well segmentation, and instrumentation. The initial field trial is ongoing in the injector of a Northern Alberta steam-assisted gravity drainage (SAGD) well pair.

Depending on the level of heterogeneity present in the reservoir, the application modeling shows that a 45% reduction in the steam-oil ratio and an almost 70% increase in recovery can be achieved in a SAGD process when both improved injection conformance and producer differential steam-trap control can be applied in a segmented horizontal well pair. A cost-effective intelligent completion solution to achieve this segmentation and control has the potential to add substantial value to field developments resulting in increased energy efficiency and oil recovery through improved steam conformance. The method being developed is also applicable to a wide range of other thermal EOR processes such as cyclic steam stimulation (CSS), steam drive and variations, which include those processes involving solvent additives. The initial field deployment in the injector well was conducted primarily to prove the technology, to demonstrate the feasibility of modifying the steam distribution, and to determine best practices for future developments. A successful installation and commissioning of the intelligent completion has validated the technology substantially. Lessons learned are highlighted.

Early injection test results and data show a significant increase in the understanding of the injection and production behavior in the well pair. The intelligent completion technology under trial and proposed developments should enable more extensive use of downhole measurement and control in thermal EOR projects than has been possible to date. This paper discusses the development of the completion technology, its applicability to thermal conditions, initial field trial results and the plans for further development. A test program to optimize the distribution of the steam injection in the well is underway, and the results to date also will be discussed.
What's The Optimum Well Geometry & Reservoir Parameters in Fracture Carbonate Reservoir Subjected to Steam Stimulation?
Authors: Makkar Fayez A. , Makkar Mariam F. , Makkar Nancy F.
Published: December 2011

As conventional-oil resources are depleted worldwide, vast heavy oil reserves become important as a secure future energy source utilizing thermal or/and non thermal methods. Significant improvements to the effectiveness of these methods can be achieved by developing a basic understanding of the complex displacement mechanisms, developing new techniques, and optimal strategies for in situ characterization of fluid and reservoir characteristics.

Thermal recovery method has been proved as a successful method for heavy oil recovery either cyclic stimulation, steam flooding stimulation or in situ combustion method in order to reduce oil viscosity, increase oil mobility, change the wettabilitiy of the reservoir and also reduce the residual oil saturation. Fracture carbonate reservoirs add more challenge to produce heavy oil, because of dual porosity and severe heterogeneity are occurring in such type of reservoirs.

Steam flooding is preferably applied in low viscosity formation less than 1,000 CP and in shallow depths less than 3,000 ft. Steam zone, hot waterflood zone, cold waterflood zone are formed when steam injected in reservoir consequent mechanisms occurred during steam flooding stimulation are; Gas drive effect of steam displaces the highly mobilized oil in the steam zone, many pore volumes of the steam reduce the oil saturation in the steam zone from initial oil saturation, thermal expansion of oil helps increase its mobility, steam distillation, and also when the temperature increase the relative permeability of oil increases and that to water decreases.

A simulation study has been undertaken to explore the optimum development method of heavy oil recovery in fracture carbonate reservoir with 11.7° API and subjected to steam flooding stimulation which is much like water flooding with arrays of injectors and producers that depend on a pattern size. This is applied on a sector model of 2500 × 2500 ft (Fig. 1) utilize compositional, thermal, and dual porosity options. Different sensitivities have been examined such as well spacing, number of injectors and producers, well completion, sensitize the injection and production parameters, and well type (vertical or horizontal) to evaluate each sensitivity effect on the oil recovery.
The Interpretation of Polymer Coreflood Results for Heavy Oil
Authors: Levitt David , Jouenne Stephane , Bondino Igor , Gingras Jean-Philippe , Bourrel Maurice
Published: December 2011

Polymer and alkali-polymer (AP) flooding are investigated in laboratory corefloods for potential application in a 2000 cP – 5000 cP heavy oil field. An augmentation of oil recovery is noted with the addition of very low concentrations of partially-hydrolyzed polyacrylamide (HPAM), either in secondary or tertiary (i.e. after waterflooding) injection. However, increasing polymer viscosity from 3 cP to 60 cP does not significantly change recovery from two pore volumes (PV) of tertiary polymer injection. Injection of alkali with polymer either in tertiary mode or subsequent to polymer injection yields a significant increase in oil recovery, and is accompanied by a drop in pressure gradient when it follows a polymer slug of similar viscosity. Existing scaling groups for viscous instability are investigated and corefloods in this study and others are found to be in the transition zone or the pseudostable region, while field floods are all in the latter. Growing evidence suggests that polymer flooding can be economically applied to very viscous oils, despite the pessimistic predictions of currently available scaling groups.
Squeeze Cementing Operations in a Thermal Carbonate Steamflood Pilot in the 1st Eocene reservoir, Wafra field, PZ
Authors: Hoadley Steven , Al-Yami Falah , Al-Mutairi Ghanim , Lekia Solomon , Brown Joel , Deemer Art , Al-Dhafeeri Fahad , Barge David , Kadhe Chetan S. , Nwabuogor Collins E.
Published: December 2011

A Large Scale Pilot (LSP) carbonate steamflood has been on injection in a lower targeted section of the 1st Eocene reservoir since June 2009 in the Wafra field located within the Partitioned Zone between the Kingdom of Saudi Arabia and the State of Kuwait. Initial primary oil recovery under cold production in the 1st Eocene interval has been less than 5% because of reservoir heterogeneity, low-gravity viscous oil, and lack of significant aquifer support. Several thermal project tests have been conducted since the late 1990`s to further improve the thermal recovery and understanding in Wafra carbonate reservoirs.

Key technical uncertainties for steamflooding the entire 1st Eocene carbonate reservoir include performance response by layer, reservoir heterogeneity, location and impact of barriers to vertical steam migration, scale deposition and corrosion due to reservoir-steam interactions. To gain thermal response information from different layers in a timely manner and reduce full field development uncertainties around the upper 1st Eocene intervals, the LSP wells were recently recompleted up hole from the "C" to "B" layer. In all, 41 wells, including both steam injectors and producers, were isolated in the "C" layer using cement squeeze operations.

Given the potential for highly permeable connections or conduits within the lower targeted 1st Eocene layer occurring naturally, from rock dissolution during steam injection, or from previous large acid jobs, additional considerations were included in the cement squeeze design to minimize excessive cement losses within the thermal zone. A cement squeeze process was developed to facilitate placement in a zone approaching 425°F while eliminating the possibility of the cement flash setting in the wellbore.
Oil Recovery from Thin Heavy Oil Reservoirs: The Case of the Combined Thermal Drive Pilot in the Morgan Field
Authors: Gutiérrez Dubert , Ursenbach Matt , Moore Gord , Mehta Raj
Published: December 2011

The Morgan Field in Canada produces from the Lloydminster and Sparky sands which are thin heavy oil reservoirs. Early development of the pool was with primary vertical wells in the late 1970's, with some enhanced oil recovery (EOR) projects such as cyclic steam injection and in-situ combustion attempted in the early 1980's. However, the area was essentially non-commercial after the 1986 oil price collapse. In order to regain commerciality, the operators implemented progressive cavity pumps and horizontal drilling, which have proven to be a success. Even with these advances though, recovery is estimated to be less than 10 percent of the original oil in place.

One of the EOR projects attempted was the Combined Thermal Drive (CTD) pilot which was carried out in one of the sections of the field for ten years. After a brief primary production period, the CTD pilot began in 1980 and consisted of three stages. In the first stage, cyclic steam stimulations were performed on individual wells during the first two years. In the next four years, air was added to the injection stream to perform cyclic air-steam stimulations on individual wells. In the last stage, pressure cycling in-situ combustion was performed for approximately four years.

In this paper, historical production and injection records were gathered to perform a technical and economic analysis of the project. After approximately 20 years since the shutdown of the project, the data indicate that this pilot has outperformed all of the other operations carried out in other areas of the field. Not only it has produced the largest amount of incremental oil of all the sections of the field, but it also managed to sustain high production rates for 10 years, which is unparalleled in the area. On the economic side, the data indicate that the project was experiencing a difficult time due to the 1986 oil price collapse. However, an economic analysis under current oil prices and costs suggests that it would have been both a technical and economic success.

This air injection case history represents a good opportunity for those operators facing the challenge to develop thin heavy oil reservoirs.
Kuwait's First Thermal Venture - Success with Resilient Cement
Authors: Eid Ramy , Ranavat Napal Singh
Published: December 2011

Kuwait has a considerable reserve of untapped heavy oil; plans were developed by KOC and embarked on a project to increase its oil production by 2020. Heavy oil production is an ambitious project and will be significant contributer to the overall increase in oil procuction capacity.

As the term "heavy oil" suggests, it is a very viscous oil. The most common methods of heavy oil recovery are: –Cold Heavy Oil Production with Sand (CHOPS)–Cyclic Steam Stimulation–Steam Flooding–Steam Assisted Gravity Drainage (SAGD)

With the focus on the second method, Cyclic Steam Stimulation to enhance the recovery of heavy oil, the design of the cement became important in terms of endurance over the life of the well. In this technique the casing / cement would be exposed to steam injection temperatures as high as 500°F.

In such cases, the cement sheath may crack due the extreme forces acting on the thin sheath of the cement. It is therefore important to know the Young's modulus of both the formation and the cement. This will allow the slurry properties to be adjusted by the use of additives to lower the Young's modulus of the cement to less than of that of the formation. This will prevent damage to the cement sheath.

A fit-for-purpose cement slurry was designed accordingly and applied on a South Ratqa well. Well testing during and after 45 days of steam injection demonstrated that the cement maintained its integrity despite the challenging conditions.
Evolution of In Situ Oil Sands Recovery Technology: What Happened and What’s New?
Authors: Gates Ian D. , Wang Jacky
Published: December 2011

Over the past 50 years, in-situ recovery methods for oil sands reservoirs have evolved and the patent literature is rich with different well designs, operating conditions, and recovery mechanisms. Here, the patent and literature has been analyzed to understand those features of in-situ recovery technologies that persisted through time. Over 250 hundred patents covering different well designs and injectants have been examined. A simple example of a persistent technology is the horizontal well: Steam-Assisted Gravity Drainage (SAGD) is enabled by horizontal well technology; the vertical equivalent of SAGD is not feasible as an economic recovery process. Cyclic steam stimulation (CSS) and steam-assisted gravity drainage (SAGD) are now over two decades old since invention and at this point there are few new technologies on the table which are being researched or evaluated. Most new technologies, for example, thermal-solvent, electrical heating with solvents, and toe-to-heel combustion are incremental adds on existing technology ideas proposed in the patent literature years to decades ago. Here, an analysis has been done to understand the evolution of in-situ oil sands recovery technology and what features have enabled economic recovery oil sands resources. The results reveal that a small number of features arising from the oil sands recovery process ideas dreamed, proposed, and developed over the past 50 years account for the success of current commercial oil sands recovery methods.
A Life Cycle Approach for Assessing Production Technologies in Heavy Oil Well Construction Projects
Authors: Ortiz Volcan Jose Luis , Iskandar Ramez Antonio
Published: December 2011

Heavy oils are characterized by high viscosities (i.e. resistance to flow) and high densities compared to conventional oil therefore they require the evaluation of specialized production methods with a systemic approach, since each one is a combination of technologies that works together as a system with the mission of improving recovery of hydrocarbons in an economical, safely and environmentally friendly manner. The probability that a heavy oil well will be constructed and will operate to achieve technical and economical objectives within the framework of an enhanced oil recovery plan is the product of the well construction project and well operational effectiveness.

The approach presented in this paper to assess production technologies requires whole life cycle asset analysis to account for uncertainties, risks and reliability in a reservoir-well-surface production system model representing all potential cause effect relations and failure modes to identify the origin of future potential production problems and its classification based on availability of data and the use of analogs for each decision category.

The proposed approach has eight processes: 1) Data gathering and reliability analysis, 2) identification of uncertainties, 3) Determination of potential production problems and risks, 4) Identification and analysis of causes of problems at reservoir level, well drainage area and surface 5) Definition of corrective and preventive actions and associated cost and time implications, 6) selection of production technologies options and scenarios, 7) Stochastic modeling of costs, cycle time, resources and system effectiveness for each scenario and 8) Solution design with the required actions for controlling or handling production problems during the life cycle of the field.

The solution is modeled with systems dynamics or stochastic simulation to calibrate life cycle costs, benefits, cycle time and required resources and data acquisition to close the loop during the life cycle of the field.

Two heavy oil field examples undergoing appraisal and development are used to illustrate how this approach allows for multiple scenarios with combination of options for key decision variables to generate a robust business case during visualization of production response of heavy oil well construction projects.
Detecting and Predicting Accounting Irregularities: A Comparison of Commercial and Academic Risk Measures
Authors: Price Richard A , Sharp Nathan Y. , Wood David A.
Published: December 2011

SYNOPSIS

Although a substantial body of academic research is devoted to developing and testing risk proxies that detect accounting irregularities, the academic literature has paid little attention to commercially developed risk measures. This is surprising given the general consensus that academic risk measures have relatively poor construct validity. We compare the commercially developed Accounting and Governance Risk (AGR) and Accounting Risk (AR) measures with academic risk measures to determine which best detects financial misstatements that result in Securities and Exchange Commission enforcement actions, egregious accounting restatements, and shareholder lawsuits related to accounting improprieties. We find that the commercially developed risk measures outperform the academic risk measures in all head-to-head tests for detecting misstatements. The commercial measures also perform as well as or better than the academic measures in new tests that predict future accounting irregularities using numbers reported one year before the misreporting even begins. Our results suggest commercially developed risk proxies can be useful to practitioners and academics when trying to detect or predict accounting irregularities.

JEL Classifications: M41; G30; K22.

Data Availability: Contact the authors.
Flex or Break? Extensions in XBRL Disclosures to the SEC
Authors: Debreceny Roger S. , Farewell Stephanie M. , Piechocki Maciej , Felden Carsten , Gräning Andre , d'Eri Alessandro
Published: December 2011

SYNOPSIS

The Securities and Exchange Commission (SEC) has adopted the eXtensible Business Reporting Language (XBRL) in a multi-year program to enhance the functionality of the Commission's EDGAR database. Filers tag their financial statements with elements from a taxonomy that defines the reporting concepts so that the XBRL files can be understood by information consumers. The U.S. GAAP taxonomy was designed to represent common reporting practices and support the disclosure requirements of U.S. GAAP. If taxonomy elements for each disclosure concept are not present, the filer creates an extension element. Extensions, when used appropriately, provide decision-relevant information. When used inappropriately, particularly when a semantically equivalent element already exists in the foundation taxonomy, extensions add no information content. This research analyzes extensions made in a subset of XBRL filings made to the SEC between April 2009 and June 2010. Forty percent of these extensions were unnecessary, as semantically equivalent elements were already in the U.S. GAAP taxonomy. Extensions that aggregated or disaggregated existing elements comprised 21 percent of the extensions. New concepts accounted for 30 percent of the extensions, although many were variants of existing elements, rather than significantly new concepts.
Discrete Laplace cycles of period four
Authors: Schröcker Hans-Peter
Published: December 2011

We study discrete conjugate nets whose Laplace sequence is of period four. Corresponding points of opposite nets in this cyclic sequence have equal osculating planes in different net directions, that is, they correspond in an asymptotic transformation. We show that this implies that the connecting lines of corresponding points form a discrete W-congruence. We derive some properties of discrete Laplace cycles of period four and describe two explicit methods for their construction.
Performance of High-Rate Kinematic GPS During Strong Shaking: Observations from Shake Table Tests and the 2010 Chile Earthquake
Authors: Wang G. , Blume F. , Meertens C. , Ibanez P. , Schulze M.
Published: December 2011

Performance of High-Rate Kinematic GPS During Strong Shaking: Observations from Shake Table Tests and the 2010 Chile Earthquake

Over the last decade, the 1-sample-per-second kinematic Global Positioning System (GPS) has been used as a displacement sensor in earthquake observations and for structural health monitoring. Many researchers in both seismology and engineering have expressed the desire for higher-sample-rate (10-sample-per-second or higher) GPS data to acquire high-frequency displacement information. We performed several shake table tests of GPS observation on 29 April, 2009 for the purpose of evaluating the performance of high-rate kinematic GPS. We found that the accuracy of high-rate kinematic GPS depended on antenna movement, but was independent of receiver sampling rate. The errors in kinematic GPS measurements during the periods of strong shaking were systematically larger than those during the static periods. Furthermore, we found that these large errors were coincident with large accelerations and jerks in the motions experienced by the GPS receivers and antennas. Observations from the 2010 earthquake in Maule, Chile (M 8.8) indicated that strong ground motions can degrade the accuracy of high-rate kinematic GPS measurements. Significant jerks and/or accelerations can cause GPS units to temporarily lose tracking on satellite signals and lead to gaps in GPS-recorded seismograms.
Differences in Travel Behavior and Demand Potential of Tram-and Bus-Based Neighborhoods
Authors: Scherer Milena , Weidmann Ulrich
Published: December 2011

One of the most contentious issues in public transport planning is whether passengers react differently to rail-based public transport and to bus-based public transport. A key problem is the difficulty in comparing the two modes. Specifically, rail-based modes are often built in higher-density environments that have higher latent public transport demand. Bus routes rarely offer the same service qualities (travel speed, service frequency) as rail service does. An approach that uses cluster analysis of public transport services as a basis for further comparison can account for these evaluated methodological shortcomings. This approach provides the opportunity to compare bus and rail under similar conditions. The authors describe the cluster analysis in which bus and rail transport in Zurich and Berne, Switzerland, were compared. The research considered several public transport qualities regarding travel time, frequency, and number of lines between bus and tram service to a particular stop. Where equivalent service qualities were provided, no significant higher effect existed in tram-based clusters compared with bus-based clusters. Nevertheless, demand potential (defined as numbers of residents and jobs) differed between clusters.
Income Effects and Other New Findings on Complexity of Transit Tours
Authors: Bernardin Vincent L. , Swenson Andrew , Jiang Zhuojun , Grovak Michael
Published: December 2011

Tours involving the use of public transit have always been viewed as less complex–including fewer stops and types of activities within a tour–than tours made by automobile or other modes. However, this traditional hypothesis was developed and supported by household travel surveys that included a relatively small subsample of transit users. The authors present a report on recent onboard transit ridership surveys in Indianapolis, Indiana, and Columbus, Ohio, that were used to collect information on the complexity of transit riders’ tours. The results suggested that, contrary to common belief, transit tours were at least as complex as tours by other modes, on the basis of household surveys of the same regions. Results of the new surveys also revealed that income and vehicle ownership had a significant and opposite effect on the complexity of transit tours than they had on tours by other modes. Thus, the traditional hypothesis of simpler transit tours held for more affluent transit users but did not hold for a typical, less affluent transit user. Comparisons of the results of the onboard and household surveys further suggested that the traditional hypothesis of simple transit tours might have arisen from a bias toward more affluent riders in the subsample of household travel surveys that contained transit. The overall finding that transit tours may actually be more complex and involve more types of activities than previously thought has important implications for transit planning.
Psychological Factors Influencing Behavioral Intention toward Future Sky Train Usage in Phnom Penh, Cambodia
Authors: Long Borith , Choocharukul Kasem , Nakatsuji Takashi
Published: December 2011

A study is presented on an extension of the theory of planned behavior (TPB) to investigate the commuter's behavioral intention toward future sky train usage in Phnom Penh, the capital city of Cambodia. Several psychological factors and socioeconomic variables that might help explain the likelihood of future sky train usage were measured by a questionnaire survey. Responses were collected from 398 motorcyclists who traveled along the planned sky train line linking the central market in the central business district to the airport. The survey was conducted on the basis of psychological constructs, including attitude, subjective norm, perceived behavioral control, moral obligation, and awareness of consequence. With structural equation modeling, it was found that the main TPB constructs, that is, attitude, subjective norm, and perceived behavioral control, significantly influenced the behavioral intention of using the future sky train. A further investigation revealed that moral obligation and the awareness of consequences were also found to be significant determinants for the behavioral intention. In addition, to some degree, socioeconomic variables can also be used to explain the intention. The outcome of the study can help in understanding commuters’ current behavioral intention and give some ideas on the feasibility of such an investment in regard to potential demand.
Flowable Fill for Rapid Pavement Repair
Authors: Griffin Jonathon R. , Brown E. Ray
Published: December 2011

The federal, state, and local highway authorities in the United States invested $3.9 billion in the rehabilitation of roughly 8,000 mi of pavement in 2008. This significant investment emphasizes the importance of ensuring that rehabilitation techniques perform well to help reduce the high annual cost for repairs. The repair of pavement base layers with compacted lifts of crushed aggregate requires specialized labor and equipment, contributes significantly to total construction time, is very difficult to perform—particularly in restricted access areas—and often results in a poorly constructed repair and loss in performance. Flowable fill technology has shown some success when used for backfilling patches and utility cut repairs. The purpose of this paper is to present performance and cost advantages of using preblended flowable fill for rapid repair of damaged areas in highway and airfield pavements. Eleven commercially available flowable fill blends were evaluated with laboratory and field testing methods. The laboratory evaluation consisted of standard material characterization testing including compressive strength, flowability, hardening time, and excavatability. Field testing included constructing and trafficking simulated utility cuts and full-depth patches in existing pavements. An examination of structural capacity, surface deformation, and visible surface distress was conducted for each repair at regular traffic intervals. In addition, construction time, difficulty, and cost were compared with those of a traditional aggregate repair. Testing results indicate that backfilling utilities and patches in pavements with flowable fill reduce the potential for premature failure, reduce construction time, and reduce total project cost while increasing repair performance.
Off-Hour Deliveries in Manhattan, New York City
Authors: Brom Matthew A. , Holguín-Veras José , Hodge Stacey Darville
Published: December 2011

This paper discusses the responses of participants in an off-hour delivery (OHD) pilot test to a postparticipation opinion survey. The pilot test was part of a project that investigated the use of financial incentives to receivers as a method to encourage OHD. The participants in the pilot test included eight carriers and 25 receivers; 12 used staffed OHD while the other 13 used unassisted OHD. In addition to the survey responses, information obtained from in-depth interviews with six of the participants provides insight into the operational benefits and potential difficulties of implementing OHD. Analysis of the responses indicates that carriers, receivers, and delivery drivers have a generally very favorable impression of their participation in OHD and shows that providing a financial incentive to receivers to encourage OHD is beneficial. Carriers saw reductions in costs, drivers experienced improved delivery conditions, and receivers saw substantial operational improvements such as being able to make better use of their staff as a result of the increased reliability of OHD. The potential of unassisted OHD is evidenced by the fact that most participants who used unassisted OHD during the pilot test continue to perform OHD without the financial incentive that was provided during the pilot test.
Estimating the Benefits of considering Travel Time Variability in Urban Distribution
Authors: Thompson Russell G. , Taniguchi Eiichi , Yamada Tadashi
Published: December 2011

Urban distribution systems typically require carriers to deliver goods to receivers within specified time windows. This paper presents procedures that allow the variable nature of travel times to be incorporated within optimization methods for the vehicle routing problem with time windows. Expressions are presented for determining the penalty costs associated with truck arrivals at customer locations with time windows when the travel times between customers are normally distributed. Formulations of this problem using stochastic programming and robust optimization (RO) are presented. Stochastic programming procedures require numerical integration techniques to be used and thus are computationally demanding. However, RO allows solutions to be generated with only a limited number of travel time scenarios between customers and, thus provides a practical means of incorporating travel time variability. A procedure was developed for estimating the cost savings of implementing the RO solution. The benefits of explicitly considering the variability of travel times between customers were estimated using a case study based on a distribution problem in Melbourne, Australia.
Identifying Surface Transportation Vulnerabilities and Risk Assessment Opportunities under Climate Change
Authors: Walker Lindsay , Figliozzi Miguel A. , Haire Ashley R. , MacArthur John
Published: December 2011

Transportation departments are beginning to recognize that adaptation for climate change must become an integral part of their planning efforts. However, staff members frequently lack the adequate local data, training, and guidance needed to begin adaptation planning assessments. As a result, planning for adapting to climate change has remained generally abstract and lacks the specificity needed to identify potential system vulnerabilities, assess risk, and prioritize responses. This report outlines a geographic information system–based method with which transportation departments can assess vulnerabilities to climate change in their multimodal surface transportation systems. The city of Portland, Oregon, is used as an illustrative case study. The proposed method allows for preliminary vulnerability identification, prioritization, and impact assessment and can also be used as a basis for more advanced analysis and scenario testing. This research also identifies and describes data gaps and other barriers to climate change adaptation planning for surface transportation.
Continuous Improvement in Regional Household Travel Surveys
Authors: Chiao Kuo-Ann , Argote Jorge , Zmud Johanna , Hilsenbeck Kim , Zmud Mia , Wolf Jean
Published: December 2011

Funding constraints limit the ability of local and state agencies to fund quality data collection efforts. At the same time, public agencies that oversee transportation programs must support planning and policy making with empirical data. As a result, transportation data users and suppliers are consistently pressed to find better, faster, and cheaper ways of collecting data. Thus, continuous improvement in travel survey data methods, procedures, and tools is an imperative, not a luxury. This paper presents the implementation and results of a continuous improvement process directed by the New York Metropolitan Transportation Council (NYMTC) with regard to its regional household travel survey. The paper reports on how lessons learned from NYMTC's 1997–1998 household travel survey along with feedback from respondents were used to plan and design the 2010 household travel survey. New methods and tools that were implemented in a 2010 survey pretest are identified, and conclusions concerning the recommended survey design are provided.
Analysis of Freight Global Positioning System Data
Authors: Sharman Bryce W. , Roorda Matthew J.
Published: December 2011

Many firms use Global Positioning System (GPS) trackers to monitor their vehicle fleets. Such data are increasingly being made available to researchers and provide a rich source of information to support modeling of the freight system. The objective of this paper is to determine the best procedure for clustering GPS trip ends into repeated visits to common destinations. This clustering allows the GPS data to be used for analyzing the repetitiveness of commercial vehicle travel and for combined models of stop frequency and stop duration. Various hierarchical agglomeration and partitioning clustering methods were compared by using data for one firm based in Toronto, Canada, that provided GPS records and driver records for a 3-month period in 2007. The analysis found that Ward's method was preferred for this application because of good clustering results and reasonable computational effort. This method was then tested on GPS data for 40 firms by using visual inspection of the clustering results. Issues were identified in the use of a single clustering distance threshold. A novel two-step clustering procedure was developed to address the issues. First, the GPS trip ends were clustered by using Ward's method. Second, clusters whose median GPS point fell within the boundary of a single property were combined. Results from the two-step clustering procedure are promising. Preliminary analysis indicated that few destinations were visited on a daily basis. Hence, travel behavior for commercial vehicles for one day is often not representative of other days; this aspect highlights concerns about travel demand models estimated by using a travel data set collected over short time periods.
Online Data Repository for Statewide Freight Planning and Analysis
Authors: Tok Andre Y. C. , Zhao Miyuan , Chow Joseph Y. J. , Ritchie Stephen , Arkhipov Dmitri
Published: December 2011

Freight transportation has a multifaceted impact on the economy, and the importance of understanding freight demand is increasing. There is a significant need to access a wide array of data sources for freight modeling and analysis. However, current data sources are not always easily accessible even with the availability of the Internet. Among the reasons are differing user interfaces, unavailability of data type definition, data format incompatibility, and inability to assess the scope of data conveniently. The repository developed in this study, the California Freight Data Repository, is a user-centered online tool designed from a systems perspective with several objectives. First, it facilitates convenient access, standardized interface, and a centralized location for obtaining freight data. Data dictionaries and lookup tables are provided for each data source to allow users to understand the scope of the data source and to give a clear definition of terms found in the data. A quality assessment summary is also provided to inform users of the strengths and limitations associated with each data source. Second, the repository is equipped with several geographic information system–based visualization tools intended to allow users to perform preliminary evaluation of data to determine their suitability for specific modeling or analysis needs. Third, the repository is designed with a customized search engine to retrieve web resources specifically associated with freight modeling and analysis. This paper presents the metadata architecture used for identifying data sources, the assessment framework used to evaluate selected data sources, and the system and interface design of the California Freight Data Repository. Several use cases are presented to demonstrate the applicability of this resource.
Wave Velocity Estimation through Automatic Analysis of Cumulative Vehicle Count Curves
Authors: Chiabaut Nicolas , Leclercq Ludovic
Published: December 2011

A fundamental diagram of traffic flow (and thus wave velocity) under congested traffic conditions is estimated from cumulative vehicle count curves. A new method estimates jam density and congested wave velocity simultaneously on a macroscopic scale. Based on kinematic wave model properties, this method overcomes the drawbacks of existing estimation processes. The objective is to determine the optimal parameters of the kinematic wave model on field data by focusing on wave propagation. The proposed method is used to automatically estimate parameters of the fundamental diagram for the study site. The fundamental diagram is linear in its congested part at the macroscopic scale. A sensitivity analysis is performed to observe the impact of observation days and loop detector locations on wave velocity under congested traffic conditions.
Detection Distances to Crosswalk Markings
Authors: Fitzpatrick Kay , Chrysler Susan T. , Iragavarapu Vichika , Park Eun Sug
Published: December 2011

The objective of this study was to investigate the relative daytime and nighttime visibility of three crosswalk marking patterns (transverse lines, continental markings, and bar pairs). In general, this study collected information on the distance from the crosswalk when the participant verbally indicated its presence. The 78 participants were about evenly divided between male and female groups and between younger (<55 years) and older (≥55 years) groups. The study was conducted with instrumented vehicles on an open road route on the Texas A&M University campus during November 2009. Data were collected during two periods: daytime (sunny and clear or partly cloudy) and nighttime (street lighting on). Markings were installed for this study at nine midblock locations. The detection distances for bar pairs and continental markings were similar, and they were statistically longer than the detection distances for the transverse markings, both day and night.
Malfunction Flash Mode Policies and Practice
Authors: Jenior Pete , Hunter Michael , Bansen Justin
Published: December 2011

From time to time, traffic signal hardware may experience a malfunction, which automatically places the intersection into flashing operation. While in flash, the signal indications that may be presented to the motorist consist of red–red flash (i.e., flashing red indications presented to all movements) or yellow–red flash (i.e., flashing yellow indications presented to the main-line movement and flashing red to all other movements). Transportation agencies must select one of these two flash modes for intersection malfunction flash events. This paper summarizes current malfunction flash policies and practice. The paper includes a review of state department of transportation policies and guidance related to malfunction flash and the results of a survey of state and local agency officials responsible for traffic signals. No general guidance was found to inform uniformity in flash mode selection. The choice between yellow–red and red–red flash is made on an agency-by-agency basis. Of the signal agencies surveyed, widespread differences were identified in the causes of malfunction flash, flash mode selection policies, notification methods, and maintenance procedures. This study highlights the need for the development of consistent flash mode policies at the national and state levels.
Cranialization of the frontal sinus—the final remedy for refractory chronic frontal sinusitis
Authors: van Dijk J. Marc C. , Wagemakers Michiel , Korsten-Meijer Astrid G. W. , Kees Buiter C. T. , van der Laan Bernard F. A. M. , Mooij Jan Jakob A.
Published: December 2011

Object

Chronic sinusitis can be a debilitating disease with significant impact on quality of life. Frontal sinusitis has a relatively low prevalence, but complications can be severe due to its anatomical location. After failure of conservative measures, typically endoscopic procedures are performed to improve the drainage of the frontal sinus. The cranialization of the frontal sinus is the final surgical measure, in which the affected frontal sinus is truly removed. In this study the authors describe the surgical technique of cranialization of the frontal sinus for refractory chronic frontal sinusitis, systematically search the literature for its application, and assess patient satisfaction in a cohort of consecutively treated patients after long-term follow-up.

Methods

A consecutive cohort of 15 patients with refractory chronic frontal sinusitis was treated by cranialization of the frontal sinus and followed over a 20-year period (1989–2008) for the direct results and complications of the surgery. Long-term follow-up (mean 6.5 years) was obtained to assess the long-term effects of the cranialization.

Results

In all patients the signs and symptoms of chronic frontal sinusitis responded very well to the cranialization. Five patients had surgical complications, of which 2 were serious. One patient died of an unrelated cause and 1 patient was lost to follow-up. The remaining 13 patients had a long-term follow-up, which revealed that 12 of them thought that their life was better after the surgical procedure.

Conclusions

Cranialization of the frontal sinus deserves consideration as the final remedy for refractory chronic frontal sinusitis after definite failure of other options.
Bone morphogenetic protein–induced inflammatory cyst formation after lumbar fusion causing nerve root compression
Authors: Choudhry Osamah J. , Christiano Lana D. , Singh Rahul , Golden Barbara M. , Liu James K.
Published: December 2011

Bone morphogenetic protein (BMP) has been reported to cause early inflammatory changes, ectopic bony formation, adjacent level fusion, radiculitis, and osteolysis. The authors describe the case of a patient who developed inflammatory fibroblastic cyst formation around the BMP sponge after a lumbar fusion, resulting in compressive lumbar radiculopathy. A 70-year-old woman presented with left L-4 and L-5 radiculopathy caused by a Grade I spondylolisthesis with a left herniated disc at L4–5. She underwent a minimally invasive transforaminal lumbar interbody fusion with BMP packed into the interbody cage at L4–5. Her neurological symptoms resolved immediately postoperatively. Six weeks later, the patient developed recurrence of radiculopathy. Radiological imaging demonstrated an intraspinal cyst with a fluid-fluid level causing compression of the left L-4 and L-5 nerve roots. Reexpoloration of the fusion was performed, and a cyst arising from the posterior aspect of the cage was found to compress the axilla of the left L-4 nerve root and the shoulder of the L-5 nerve root. The cyst was decompressed, and the wall was partially excised. A collagen BMP sponge was found within the cyst and was removed. Postoperatively, the patient's radiculopathy resolved and she went on to achieve interbody fusion. Bone morphogenetic protein can be associated with inflammatory cyst formation resulting in neural compression. Spine surgeons should be aware of this complication in addition to the other reported BMP-related complications.
Rice Production In Bangladesh Employing By Arima Model
Authors: Awal MA , Siddique MAB
Published: December 2011

The present study was carried out to estimate growth pattern and also examine the best ARIMA model to efficiently forecasting Aus, Aman and Boro rice production in Bangladesh. It appeared that the time series data for Aus and Aman were 1st order homogenous stationary but Boro was 2nd order stationary. The study revealed that the best models were ARIMA (4,1,4), ARIMA (2,1,1), and ARIMA (2,2,3) for Aus, Aman, and Boro rice production, respectively. The analysis indicated that short-term forecasts were more efficient for ARIMA models compared to the deterministic models. The production uncertainty of rice could be minimized if production were forecasted well and necessary steps were taken against losses. The findings of this study would be more useful for policy makers, researchers as well as producers in order to forecast future national rice production more accurately in the short run.   Keywords: Production; ARIMA model; forecasting of rice. DOI: http://dx.doi.org/10.3329/bjar.v36i1.9229 BJAR 2011; 36(1): 51-62
Investigation Into Effect Of Crude Mixture Of Abrus Precatorius Seed On Hypothalamopituitary Gonadal Axis And Development Of Antifertility In Male Rats
Authors: Talukder S , Hossain MA , Sarker S , Khan MAH
Published: December 2011

To evaluate the antifertility effect of crude mixture of A. precatorius seeds at the dose level of 50 mg/kg body weight in adult male rats, after oral administration to male rats for 40 days, the rats were sacrificed and hormonal profiles, serum biochemistry, sperm count and histological changes were recorded. A sharp decrease in the serum levels of testosterone (0.70 ± 0.17 ng/ml), FSH (0.70 ± 0.22 lU/L), and LH (0.87 ± 0.35 IU/L) was detected compared to control (FSH, LH and testosterone levels 0.93 ± 0.15 ng/ml, 0.76 ± 0.28 IU/L, 1.44 ± .011 IU/L, respectively). A significant reduction of epididymal sperm count (2.34 million/mL) was noted in treated rats as compared to control group (7.87 million/mL). Histology of testes showed marked atrophy of the testes, which was characterized by disruption of the seminiferous epithelium and atrophy of the Leydig cells. Crude mixture of A. precatorius seed has a negative impact on male reproductive functions. It might be suggested that crude mixture of A. precatorius seeds might have antifertility property for male rats.   Keywords: Abrus precatorius; antifertility; male rat; testosterone. DOI: http://dx.doi.org/10.3329/bjar.v36i1.9234 BJAR 2011; 36(1): 103-109
Effect Of Alley Size And Hedgerow Pruning Interval On Phenology And Yield Of Okra [Abelmoschus Esculentus (L.) Moench] In Hill Slope
Authors: Firoz ZA , Rashid MH , Huda MS
Published: December 2011

An experiment was conducted at the Hill Agricultural Research Station, Khagrachari from May 2002 to November 2004 to find out the effect of alley size (3.0 , 4.0, and 5.0 m) and hedgerow pruning interval (1, 2, and 3 months) on phenology and fruit yield of okra in hill slope condition during the rainy season. The highest fruit yield (16.14 t/ha) was produced by the plants grown in 3.0 m size alley. In case of hedgerow pruning interval, the highest yield (16.07 t/ha was recorded from 2 months pruning interval and it was significantly different with other two pruning intervals. The treatment combination of 3.0 m size alley with I month pruning interval produced significantly highest yield (17.67 t/ha). The highest gross return (Tk.176700/ha), net return (Tk.120380/ha) and BCR (3.14) were also found from the same treatment though highest cost of production was involved in this treatment.   Key words: Alley size; pruning interval; phenology; okra yield; cost benefit. DOI: http://dx.doi.org/10.3329/bjar.v36i1.9238 BJAR 2011; 36(1): 143-150