bluuebunny/crossref_metadata_2025 huggingface dataset:
Career Intentions of Pharmacy Students
Authors: Willis Sarah , Hassell Karen , Noyce Peter
Published: April 2008

Objectives

In light of pharmacy workforce shortages in Great Britain, the profession's regulatory body commissioned a programme of longitudinal work to explore pharmacy career decisionmaking in relation to influences on career choice and intended career paths. Our objective was to gather data on career intentions that could be used to produce robust predictions about pharmacist supply.

Methods

Two annual surveys conducted with the same cohort of pharmacy students in 2005 and 2006. The questionnaires sought to clarify influences on respondents’ career intentions and their early career plans.

Results

Only two-thirds of respondents intended going straight into British pharmacy practice after training, with fewer white men (57%) than ethnic minority men (71%) intending to go straight into practice. Preferences for early careers reflected existing occupational segregation, with 41% of white females hoping to work in hospital pharmacy and a similar proportion of ethnic minority men (40%) hoping to work for a large multiple community pharmacy after training.

Conclusions

A sizeable proportion of pharmacy students do not intend entering the profession for which they have trained, a proportion which is much larger than estimated by other studies. This has significant implications for workforce planning. Existing gender and ethnic segregation in the profession may have occurred as a result of personal choice rather than being a function of constraints operating within the pharmacy labour market.
The Local Adaptation of National Recommendations for Preventing Early-Onset Neonatal Group B Streptococcal Disease in Uk Maternity Units
Authors: Cromwell David , Joffe Tracey , Hughes Rhona , Murphy Deirdre , Dhillon Charnjit , Van Der Meulen Jan
Published: April 2008

Objective

To evaluate how UK maternity unit protocols conformed to national recommendations for preventing early-onset neonatal Group B Streptococcal (GBS) disease.

Methods

In December 2005, all UK obstetric maternity units were contacted and asked to provide a copy of their protocol on preventing GBS disease. Information was extracted on the protocol's recommendations, its development date and the evidence cited. The protocol's recommendations were then compared against the recommendations in the Royal College of Obstetricians and Gynaecologists (RCOG) guideline.

Results

Protocols were obtained for 171 of the 227 units (75%), of which 120 were developed after the guideline has been published. There were 134 protocols (78%) that followed the RCOG prevention strategy, recommending a risk-based approach to selecting women for intrapartum antibiotic prophylaxis (IAP). However, the sets of risk factors named as indications for IAP differed between the protocols and only 34 of these 134 protocols were entirely consistent with the guideline. The 37 protocols (22%) that did not follow the RCOG prevention strategy recommended IAP for some risk factors but only if a bacteriological test was also GBS positive.

Conclusions

There are considerable differences in the GBS protocols used in maternity units in the UK despite the availability of a national guideline. Consequently, some high-risk women may not receive IAP while some women without risk factors are treated needlessly. While local adaptation may be for legitimate reasons, the processes used in some units seem to require improvement.
Learning from Other Countries: An On-Call Facility for Health Care Policy
Authors: Nolte Ellen , Ettelt Stefanie , Thomson Sarah , Mays Nicholas
Published: April 2008

Recognizing that robust information on health systems in other countries can provide valuable lessons for the English National Health Service, the Department of Health commissioned an academic team to provide an ‘On-call Facility for International Healthcare Comparisons’ in 2005. This paper describes the work of this novel approach to informing policy and reviews the experience of the first two years. It illustrates the well-documented challenges of comparative analysis of health systems. One important issue is understanding the health system context so as to interpret phenomena and draw appropriate policy conclusions. Other challenges include the potential tension between academic interest and rigour, and the need for timely analysis to inform the Department of Health's rapidly changing policy agenda. The diversity and nature of topics covered, as well as the rapid turn-around time have meant that the Facility has had to balance rigour and timeliness carefully to ensure the value and relevance of reports. A strong research base linked with an international network of country experts promotes the provision of high quality analyses at relatively low costs. However, such an arrangement can only be sustained if it provides scope for additional primary research. A formal evaluation of the influence on health care policy-making in England is not yet available. Such knowledge will be of crucial importance for the development of similar resources elsewhere.
Decentralizing Resource Allocation: Early Experiences with District Health Boards in New Zealand
Authors: Ashton Toni , Tenbensel Tim , Cumming Jacqueline , Barnett Pauline
Published: April 2008

Objectives

In New Zealand in 2001, a system of purchasing health services by a centralized purchasing agency was replaced by 21 district health boards (DHBs) which are responsible for both providing health services directly and for purchasing services from non-government providers. This paper describes the processes associated with the allocation of health resources in the decentralized system and considers the extent to which four of the government's stated objectives are likely to be achieved.

Methods

Two rounds of interviews with national stakeholders and senior DHB personnel plus case studies in five districts which included key informant interviews, observation at board meetings and document analysis.

Results

The re-structuring of the health sector in New Zealand appears to have simultaneously enhanced and inhibited the achievement of government objectives. Local decisionmaking has encouraged greater local responsiveness and new funding arrangements have allayed concerns about inter-regional equity. The system is less commercially oriented than it was during the 1990s and collaboration between DHBs is improving. However, the combination of increased integration of purchasing and provision within DHBs and the focus on financial deficits in the early years appears to have inhibited the development of partnership relationships between DHBs and non-government providers, and of longer-term funding arrangements for high quality providers. Non-government providers perceive that DHBs have a tendency to favour their own providers when allocating contracts.

Conclusions

Decentralized decisionmaking is starting to make some inroads towards achieving some of the government's objectives with respect to resource allocation and purchasing.
A Bivariate Timing Model of Customer Acquisition and Retention
Authors: Schweidel David A. , Fader Peter S. , Bradlow Eric T.
Published: April 2008

Two widely recognized components, central to the calculation of customer value, are acquisition and retention propensities. However, while extant research has incorporated such components into different types of models, limited work has investigated the kinds of associations that may exist between them. In this research, we focus on the relationship between a prospective customer's time until acquisition of a particular service and the subsequent duration for which he retains it, and examine the implications of this relationship on the value of prospects and customers.

To accomplish these tasks, we use a bivariate timing model to capture the relationship between acquisition and retention. Using a split-hazard model, we link the acquisition and retention processes in two distinct yet complementary ways. First, we use the Sarmonov family of bivariate distributions to allow for correlations in the observed acquisition and retention times within a customer; next, we allow for differences across customers using latent classes for the parameters that govern the two processes. We then demonstrate how the proposed methodology can be used to calculate the discounted expected value of a subscription based on the time of acquisition, and discuss possible applications of the modeling framework to problems such as customer targeting and resource allocation.
Security Patch Management: Share the Burden or Share the Damage?
Authors: Cavusoglu Hasan , Cavusoglu Huseyin , Zhang Jun
Published: April 2008

Patch management is a crucial component of information security management. An important problem within this context from a vendor's perspective is to determine how to release patches to fix vulnerabilities in its software. From a firm's perspective, the issue is how to update vulnerable systems with available patches. In this paper, we develop a game-theoretic model to study the strategic interaction between a vendor and a firm in balancing the costs and benefits of patch management. Our objective is to examine the consequences of time-driven release and update policies. We first study a centralized system in a benchmark scenario to find the socially optimal time-driven patch management. We show that the social loss is minimized when patch-release and update cycles are synchronized. Next, we consider a decentralized system in which the vendor determines its patch-release policy and the firm selects its patch-update policy in a Stackelberg framework, assuming that release and update policies are either time driven or event driven. We develop a sufficient condition that guarantees that a time-driven release by the vendor and a time-driven update by the firm is the equilibrium outcome for patch management. However, in this equilibrium, the patch-update cycle of the firm may not be synchronized with the patch-release cycle of the vendor, making it impossible to achieve the socially optimal patch management in the decentralized system. Therefore, we next examine cost sharing and liability as possible coordination mechanisms. Our analysis shows that cost sharing itself may achieve synchronization and social optimality. However, liability by itself cannot achieve social optimality unless patch-release and update cycles are already synchronized without introducing any liability. Our results also demonstrate that cost sharing and liability neither complement nor substitute each other. Finally, we show that an incentive-compatible contract on cost sharing can be designed to achieve coordination in case of information asymmetry.
Inventory Management with Advance Demand Information and Flexible Delivery
Authors: Wang Tong , Toktay Beril L.
Published: April 2008

This paper considers inventory models with advance demand information and flexible delivery. Customers place their orders in advance, and delivery is flexible in the sense that early shipment is allowed. Specifically, an order placed at time t by a customer with demand lead time T should be fulfilled by period t + T; failure to fulfill it within the time window [t, t + T] is penalized. We consider two situations: (1) Customer demand lead times are homogeneous and demand arriving in period t is a scalar dt to be satisfied within T periods. We show that state-dependent (s, S) policies are optimal, where the state represents advance demands outside the supply lead-time horizon. We find that increasing the demand lead time is more beneficial than decreasing the supply lead time. (2) Customers are heterogeneous in their demand lead times. In this case, demands are vectors and may exhibit crossover, necessitating an allocation decision in addition to the ordering decision. We develop a lower-bound approximation based on an allocation assumption, and propose protection-level heuristics that yield upper bounds on the optimal cost. Numerical analysis quantifies the optimality gaps of the heuristics (2% on average for the best heuristic) and the benefit of delivery flexibility (14% on average using the best heuristic), and provides insights into when the heuristics perform the best and when flexibility is most beneficial.
Ship Scheduling and Network Design for Cargo Routing in Liner Shipping
Authors: Agarwal Richa , Ergun Özlem
Published: April 2008

Acommon problem faced by carriers in liner shipping is the design of their service network. Given a set of demands to be transported and a set of ports, a carrier wants to design service routes for its ships as efficiently as possible, using the underlying facilities. Furthermore, the profitability of the service routes designed depends on the paths chosen to ship the cargo. We present an integrated model, a mixed-integer linear program, to solve the ship-scheduling and the cargo-routing problems, simultaneously. The proposed model incorporates relevant constraints, such as the weekly frequency constraint on the operated routes, and emerging trends, such as the transshipment of cargo between two or more service routes. To solve the mixed-integer program, we propose algorithms that exploit the separability of the problem. More specifically, a greedy heuristic, a column generation-based algorithm, and a two-phase Benders decomposition-based algorithm are developed, and their computational efficiency in terms of the solution quality and the computational time taken is discussed. An efficient iterative search algorithm is proposed to generate schedules for ships. Computational experiments are performed on randomly generated instances simulating real life with up to 20 ports and 100 ships. Our results indicate high percentage utilization of ships' capacities and a significant number of transshipments in the final solution.
Voyeuristic Abolitionism: Sex, Gender, and the Transformation of Antislavery Rhetoric
Authors: Lasser Carol
Published: April 2008

In the 1830s, antislavery advocates used highly sexualized language to recruit Northerners into the growing immediatist movement. The "voyeuristic abolitionism" they developed in speeches, pamphlets and periodicals served to shock and mobilize men and especially women, who were urged to identify with the enslaved of their own sex, and then to act to save these victims. Engaging women in such explicit discussions and encouraging female efforts to strike against slavery challenged established gender norms. Yet as the antislavery movement evolved beyond moral suasion into a political strategy, most abolitionists curtailed their use of sexualized imagery, and women's participation in the antislavery movement took its own form. The rise and fall of the rhetoric of "voyeuristic abolitionism" can be charted by studying the vocabulary used in magazines and other popular publications of the era, now searchable electronically through the American Periodical Series. The explosive potential of this language can also be seen in the ways in which it was employed -and avoided-in the U.S. Congress. By the 1850s, some Americans-among them African American authors and antislavery women, including most notably Harriet Beecher Stowe--found ways to reference the moral evils of slavery without invoking explicitly sexual language. In the end, attacks on slavery framed in political terms prevailed over the voyeuristic abolitionism that had first drawn women into the antislavery coalition.
Swearing at—not by—History: Obscenity, Picong and Irony in Derek Walcott's Poetry
Authors: Lagapa Jason
Published: April 2008

Most critics of Derek Walcott writing focus their praise either on eloquently phrased Standard English or his inventive use of Caribbean vernacular, yet few have considered swearing and obscenity as integral aspects of Walcott's poetics. Though the impulse may be to dismiss the profanity as an aberration of poetic language, these obscenities should not be taken as anomalies. On the contrary, Walcott's use of profane language indicates a negative and ironic poetics at work: by integrating profanity into his poetry, Walcott explores how coarse language can counteract the staidness of "refined" poetic diction, and he also demonstrates how obscenity can inform an innovative poetics that redefines epic poetry and the epic hero through parody. The recognition of Walcott's use of swearing in order to parody the epic tradition, moreover, elucidates Walcott's nuanced understanding of the complexities of Caribbean history, as Walcott refutes those who would view Caribbean history as non-existent.
The Peasant and the Monster in the Macaronic Works of Teofilo Folengo
Authors: Scalabrini Massimo
Published: April 2008

In this paper I focus on the works of Teofilo Folengo (1491-1544), Italy's foremost macaronic poet. I address the contaminated nature of Folengo's macaronic (a richly-textured language combining classical Latin and Mantuan dialect, with elements of Medieval and Humanist Latin as well as literary Italian), and I explore some of its stylistic and thematic implications. I devote special attention to the representation of the peasant in works such as the Zanitonella and the Baldus, and I show how the old peasant Tognazzus reproduces the monstrous features of Polyphemus, the Cyclops of the epic and bucolic tradition.
L’Arcadia sulla luna: un’inversione pastorale nell’ Orlando Furioso
Authors: Gulizia Stefano
Published: April 2008

Questo saggio offre una ravvicinata lettura retorica e stilistica dell'episodio lunare dell'Orlando furioso e, in particolare, dell'ottava, in cui al paladino Astolfo si offre per la prima volta un'immagine della luna (34. 72), in cui Ariosto inserisce un'imitazione tratta dall'Arcadia di Sannazaro. La pastorale ariostesca, compressa in una singola stanza, si dimostra cruciale per la comprensione delle premesse umanistiche del Furioso: le conclusioni dello studio argomentano l'importanza dell'allegoria dantesca, sia pure mediate attraverso un filtro dissacratorio, e la presenza di un cortocircuito gnoseologico alimentato dal cronòtopo arcadico e la sua inversione lunare nell'epos di Ariosto
In the Book We have left out Nothing: The Ethical Problem of the Existence of Verse 4:34 in the Qur’an
Authors: Silvers Laury
Published: April 2008

Kecia Ali writes in her book Sexual Ethics and Islam that studies on the history and forms of gender injustice in Islam have yet to adequately address concomitant theological challenges concerning the nature of the divine justice and will. In response to this need, I would like to explore the problem posed by the mere existence of verse 4:34, otherwise known as “the beating verse,” in the Qur’an. This article is intended to be a primary theological and ethical response to the problem, rather than a secular academic analysis of historical approaches to the verse. My approach is grounded in the thought of Ibn al-`Arabi (d. 1240), arguably the most influential, systematically comprehensive, and prolific mystic and thinker of medieval Islam. Ibn al-`Arabi’s ontology, ethics, and hermeneutics of the Qur’an provide a useful frame and a possible resolution to the problem.
Thermal Behavior of Multifluid-Saturated Formations Part 1: Effect of Wettability, Saturation, and Grain Structure
Authors: Gomaa Ezzat E. , Somerton W.H.
Published: April 2008

A conceptual model is developed for prediction of thermal conductivity of multi-fluid saturated formations. The model incorporates the physical properties as well as wettability and solid-fluid affinity concepts. The fluid saturation distribution, the Biot number related to the surface of contact between the solid matrix and fluids, and a grain contact parameter successfully explained the thermal behavior of given rock fluid systems.

Experimental measurements on actual rock-fluid systems confirmed the validity of the proposed method. Both the model and experimental results indicated the thermal conductivity of formations to be a function of the square root of wetting phase saturation.

The degree of compaction and cementation between solid grains of the rock is also an effective factor in determining the thermal conductivity. Being expressed in terms of a dimensionless grain contact parameter, the compaction cementation was correlated with the formation resistivity factor.

Introduction

Analyses of thermal recovery processes and geothermal steam and hot water formations require knowledge about thermal behavior and properties of multi-fluid saturated porous media. The validity of such analyses and the applicability of their results are sensitive to the reliability of these data. In particular, it is important to use the proper values of the system's thermal properties and to have a good notion about their modes of change with the existing variables.

A porous sandstone consists of a framework of solid grains, whether cemented together or not, within which pores and openings are present. Such openings are filled with different combinations of fluids. Thermal properties of these rock-fluid systems will be, of course, a certain combination of the individual properties of their constituents and a function of the existing environmental conditions. In addition these properties are functions of the modes of behavior and interactions between fluids and solid matrix.

The literature contains a considerable amount of work on different methods and techniques for measurements and prediction of some of these properties. However, such methods and data are limited to porous media saturated with a single fluid. Very little has been done on the mixed fluid saturation problem and the above effects were not quantitatively evaluated.
Thermal Behavior of Multifluid-Saturated Formations Part 2: Effect of Vapor Saturation - Heat Pipe Concept and Apparent Thermal Conductivity
Authors: Gomaa Ezzat E. , Somerton W.H.
Published: April 2008

When porous systems contain liquids at or near their vapor pressures and saturation temperatures, evaporation-condensation reactions may combine with capillary pressure gradients and greatly enhance the heat transfer capacity of the system. This behavior was simulated by the so-called Heat Pipe, a mechanism which is capable of transferring heat at rates much higher than those observed by simple conduction.

A conceptual model was derived for the theoretical analysis of the heat pipe concepts in porous media. Equations were developed for expressing the heat pipe effect in the form of an additional thermal conductivity as function of the system's characteristics.

The mechanism was illustrated experimentally by testing four different rock samples with two liquids of different latent heats of vaporization. Results, which were in consistent agreement with the derived theory, showed that vapor saturations resulted in high apparent thermal conductivities for the rock samples that was, in some cases, several times greater than the expected basic value. Both theoretical and experimental observations showed that the heat pipe effect is a function of permeability, porosity, latent heat of vaporization of the saturating liquid, vapor saturation, capillary pressure, and relative permeabilities and kinematic viscosities of the liquid and vapor phases.

A statistical correlation was obtained expressing the heat pipe effect in terms of other easy measuring properties of the physical system.

Introduction

Analyses of the processes of thermal recovery of crude oil, energy extraction from geothermal steam formations, heat transfer in packed towers, and many other important engineering applications often require knowledge of thermal behavior and properties of partially vapor saturated porous media. The effect of partial vapor saturation on thermal behavior of such materials was not fully investigated. Few authors had reported briefly that the presence of some vapor saturation in porous media samples made their thermal conductivities higher than expected. These findings were mainly experimental and in some cases they were reported as experimental errors. Theoretical explanation was not available and thus these effects were not evaluated quantitatively.

In the present work the effects of partial vapor saturation on the heat transfer characteristics of formations were considered and evaluated.
Noise Characteristics of Oil Wells and Reservoirs
Authors: Shuck L.Z. , Keech T.W.
Published: April 2008

Monitoring the acoustic emission from oil, gas, geothermal, and other reservoirs under various conditions promises to yield valuable information regarding the reservoir characteristics and the results from such processes as hydraulic fracturing conducted in the reservoir. In order to interpret the emissions generated during various operations, it was first necessary to study and evaluate the reservoir under relatively undisturbed conditions. The acoustic noise environment as seen by a hydrophone on the end of a logging cable is discussed. Hydrophone-type sensors-transducers, as used for obtaining this data, have many advantages for monitoring such acoustic emission. Measurements of ambient noise at various depths from the surface down to 2,050feet (625m) in one well and in 11 different wells at 2,030 feet (619m) were made.

From these measurements and analyses, it was found that the noise environment is in general wide-band and random. The noise can be further classified as stationary and ergodic. The noise is attenuated with depth, typically decreasing by a factor of one-half from the surface to 50.0 feet(15.2m). Typically, the time average RMS pressure amplitude had a value of 0.75to 0.8 Pa below 1,000 feet (305m) and did not vary greatly with further increases in depth. A 40 mv RMS signal corresponded to 0.8 pa(N/m2). The acoustic energy was found to have some dominant frequency bands near 450 hz and 1,200 hz. In general, the pressure signals were considerably weaker at frequencies above 2 khz where the system electronic noise became a significant portion of the overall signal.

Introduction

Acoustic monitoring of oil and gas wellbores promises to yield increasingly more information about the characteristics of reservoirs. In the past, acoustic monitoring in wellbores for any reason has been done on a rather limited scale. The monitoring of seismic waves with borehole geophones has been the principal technique used. Bois, and others have described recent experimentation in this area and give the historical developments. These seismic measurements are usually made with the objectives of exploration or seismic velocity surveys and the determination of elastic properties. The maximum frequencies of interest are 150 hz and frequently less than 10 hz.
Current Perspective on Gas Well Testing - Objectives, Methods, Procedures, Analyses and Requirements of Northern Natural Gas Company as Purchaser
Authors: Smith D.L.
Published: April 2008

Objectives of obtaining well performance data to determine quantity and quality of reserves and to provide facility design data are accomplished by utilizing producer and state test information and supplementing with company gathered data. Analysis is made by steady and unsteady-state methods on data obtained at the wellhead and bottom-hole. The use and description of the latest well test equipment, used and designed by the testing group, is also presented.

A general discussion of Northern Natural Gas Co.'s current gas well test objectives, methods, procedures, analyses and requirements from a purchaser'spoint of view is presented. Objectives of obtaining adequate well performance data to determine quality of reserves and design data are accomplished by utilizing producer and state test information and supplementing with company information. Data is collected at the wellhead if indicative of reservoir conditions. If surface datum is not reliable, bottom-hole pressure datum is obtained. Analysis is made by steady-state and unsteady-state methods as required to determine stabilized wellhead performance. This stabilized wellhead performance is projected for at least five years for use in facilities design, reserve acquisition, operating schedules, long range planning and budgeting.

Introduction

The competitive nature of natural gas as a fuel in the market place is placing more emphasis on quality and available quantity of gas reserves in the purchase areas. The collection and use of gas well test data is increasing in importance to satisfy present and future operating requirements. This discussion was written to present the current perspective of Northern Natural Gas Co.'s interest in gas well testing and how the information is gathered and utilized. Casinghead, plant or storage gas testing is not included in this discussion.

Effort is made to collect physical environment data on gas wells principally at the wellhead. Data is collected at reservoir level if liquid problems prohibit reliable prediction of reservoir characteristics from wellhead test data. The data is analyzed using selected current technology to satisfy economic environment needs such as [1] contractual obligations, [2] regulatory body requirements of adequate source data for the accounting system which enables control decisions.

Northern Natural Gas Co. currently engages in two types of gas well testing activities - initial tests before connection and recurring tests after connection. Both types of testing involve the field collection, engineering analysis, and application of gas well test data. Initial test data is gathered and analyzed to determine productivity as a function of time. The initial well productivity aids in estimating reserves and in determining qualification for connection. After connection the testing continues and original estimates are revised as needed.
Gas Well Testing - Storage
Authors: Katz Donald L.
Published: April 2008

The usual back pressure tests or inflow tests during gas injection are needed to understand gas well flow capacities. Such individual well capacities are combined into composite field deliverability curves for predicting the flowing well head pressure during heavy gas withdrawal periods. Some practices for gas storage in both depleted gas fields and aquifers are discussed.

Gas wells are tested regularly in connection with storage operations. Two types of reservoirs will be considered; depleted gas fields and aquifer storage fields. Generally, the objective is to know the flow capacity of the gas wells during the high withdrawal periods.

Depleted Gas Fields

The flow capacity of gas wells is normally determined shortly after drilling. At the time of conversion of depleted gas fields to storage, it is advisable to re-test the wells for deliverability. Such tests usually must wait until a reasonable degree of repressuring has taken place to give enough gas pressure to permit blowing the wells and to assure that the well sand face is dry. A comparison of the re-test performance with the original test indicates the degree of deterioration and whether remedial work is indicated. Fig. 1shows a Stray Sand gas well with severe deterioration during it's productive life. Any new wells drilled are tested to give their flow capacity.

The information of interest is the composite performance curve for the field. This is obtained by taking the sum of the flow capacities [Q] at a given difference of squares of the pressures. Such a field curve along with the gathering system pressure drop will give the field delivery pressure for any flow rate and gas reservoir pressure. The reservoir pressure is often observed directly by a pressure observation well to find Pf.

Flow tests are most conveniently taken in the summer time in a period corresponding to gas injection rather than withdrawal. It has been shown that inflow testing gives the same results as outflow testing and Fig. 1 shows inflow test results after conversion to gas storage. In well testing it is customary to use a deadweight pressure gage for well head pressure measurements and individual well orifices meters.

The relative close spacing of gas wells for storage removes the usual problem of unsteady state. However, before developing a reservoir, initial tests on a gas well involving unsteady state may be made in the manner followed by Robertson. The more likely problem is that a portion of the gas reservoir has high permeability and hence contains most of the deliverability capacity.
Gas Current Perspective on Well Testing in Storage Fields
Authors: Guinane J.P. , Evrenos A.I.
Published: April 2008

Introduction

Gas well testing is not new, but the practical approach which forces innovation and departure from the laboratory technique may present a challenge. This is especially true in testing wells penetrating gas storage reservoirs developed in aquifers.

It is hoped that this paper will present some of the aspects of well testing for storage fields which will also pinpoint the direction for future laboratory research. The analysis of the data is not covered in the scope of this discussion, but rather the objectives of the tests and the procedures used to conduct the tests are explored.

Since all gas well testing is performed for certain specific needs and objectives, it is not difficult to understand the reason for the approaches presented in this paper. Whether it be company justification or regulatory requirements, all storage well testing is geared to the ultimate proof of the storage reservoir. Well condition is indicated, but basically each test run on a storage well or group of wells will prove the injectability or the deliverability of each storage zone tested.

The authors' experience in gas well testing has been primarily with storage developed in aquifers. That is reservoirs which have not previously contained gas or oil. The views presented will therefore indicate actual problems associated with this type of reservoir. The similarity in many respects to conditions encountered in depleted oil and/or gas reservoirs converted to gas storage reservoirs will be of interest to those concerned with such storage facilities. The unusual aspects of gas well testing in "aquiferstorage" will point out the areas where additional research has been done or needs to be done for the progress of this phase of reservoir technology.

Gas Well Testing - Storage Fields

Gas well testing is normally concerned with the deliverability of a gas well. Gas well testing in storage fields is primarily concerned with both injectability and deliverability of a well or of many wells. As will be explained in this discussion, injection and withdrawal characteristics of an entire field may be more important or at least equally important as individual well performance.

Most storage fields are developed to fulfill a specific basic requirement of a gas company. This basic need is the ultimate efficient service to the customer. By the nature of their purpose, transmission and distribution companies are the major developers of storage projects. This may be small capacity, low volume rate service or large capacity, high volume rate service depending on the need.
Influence of Source Characteristics, Chemicals, and Flocculation on Chemically Enhanced Primary Treatment
Authors: Neupane Dilli R. , Riffat Rumana , Murthy Sudhir N. , Peric Marija R. , Wilson Thomas E.
Published: April 2008

The overall objective of this research was to investigate various methods and parameters to increase the efficiency of chemically enhanced primary treatment (CEPT). The performance of CEPT was evaluated based on its efficiency of removal of nonsettleable solids (NSS). Some of the source characteristics that influenced NSS concentration included influent total suspended solids, influent turbidity, and influent total chemical oxygen demand. A higher concentration of the influent constituents led to a higher NSS concentration, suggesting that NSS represented a somewhat fixed fraction or percent of these influent constituents. The specific particle surface area (SPSA) was found to correlate with percent NSS in the effluent. A higher SPSA is a result of smaller‐sized nonsettleable colloidal particles, thus leading to an increase in percent NSS. In summary, there are several parameters that affect NSS, which could be used to control NSS to improve CEPT, as demonstrated by this study.
The Relation between Self-Determination and Retirement Satisfaction among Active Retired Individuals
Authors: Stephan Yannick , Fouquereau Evelyne , Fernandez Anne
Published: April 2008

Little is known about the motivational forces leading retired individuals to engage in post-retirement activities and how they could be related to satisfaction with retirement. Using the self-determination framework, the purpose of the present exploratory study was to examine the nature of active retirees' motivation and its impact on satisfaction with life in retirement. The Global Motivation Scale and measures of satisfaction with retirement were administered to 150 active retired individuals engaged in organized post-retirement activities in a University-based organization. Results revealed that these individuals were mainly characterized by higher levels of intrinsic motivation for knowledge, stimulation and accomplishment, rather than extrinsic dimensions. Regression analysis further demonstrated that intrinsic motivation for both accomplishment and stimulation were positively related to satisfaction with retirement, over and above the significant contribution of time since retirement, anticipated satisfaction with retirement, and subjective health. This exploratory study highlights the motivational mechanisms through which post-retirement behaviors could positively influence satisfaction with life in retirement among active retirees.
9/11 Environmental Health—Disaster and Response
Authors: Newman David M. , Tuminaro Dom
Published: April 2008

The tragic events of 9/11/01 and thereafter resulted in the worst environmental disaster in the history of New York City. Toxic contaminants were dispersed over a wide geographic area. A variety of exposure scenarios produced clinically diagnosed persistent respiratory and other illnesses in multiple exposure populations, with fatalities beginning to be reported. Government efforts to protect public health and to assess and remediate contaminants have been minimal and sometimes have been driven by political imperatives rather than by public health principles. This article examines the scope of the environmental disaster, the statutory requirements that regulate governmental response, and the nature of government response efforts. It provides the context for a companion article also published in this issue of New Solutions. The companion article examines a grassroots environmental movement, the World Trade Center Community Labor Coalition, and its advocacy efforts for environmental cleanup and for access to health care for impacted populations and communities.
Glory Days: A Review of Bruce Miroff's The Liberals' Moment: The McGovern Insurgency and the Identity Crisis of the Democratic Party
Authors: Baer Kenneth S
Published: April 2008

Bruce Miroff's The Liberals' Moment: The McGovern Insurgency and the Identity Crisis of the Democratic Party takes a fresh look at the failed 1972 presidential campaign of George McGovern. Unfortunately, Miroff spins the story of the 1972 campaign to make a political point for today. Focusing on what he calls the "politics of insurgency," Miroff fails to adequately capture the larger, fascinating institutional story of how a candidate and his supporters transformed a party and presidential politics. In addition, he makes an ideological argument about the nature of liberalism then and now that in its elitism represents everything that was wrong with the McGovern candidacy and McGovernism.
Cadmium Biosorption on Vegetal Biomass
Authors: Salem Zineb , Allia Khedidja
Published: April 2008

Effective removal of heavy metals from wastewater is one of the most important environmental challenges facing the world. Various techniques are used to remove the metals. Biosorption has gained credibility in the last decade because of its good performance and low cost. The objective of this study is to explore the use of olive pits for cadmium wastewater removal. The effects of mixing rate, pH, particle size, biomass and initial concentration and equilibrium metal ion concentration are evaluated. Results indicate nearly linear uptake by the biomass with increasing initial cadmium concentration. Adsorption increases rapidly in the pH range of 3-9, then levels off. Cadmium concentration uptake increase with increasing biomass concentration until reaching 5 g/L. Mixing rates up to 250 rpm increase uptake, however, higher mixing rates result in a vortex that incorporated air into the mixture, this resulted in a decrease in uptake. The adsorption isotherm appears to follow the Langmuir model.
Optimization of Continuously Stirred Tank Bioreactor Design for Cost Minimization: Effect of Microbial Species and Operating Conditions
Authors: Powell Erin E , Hill Gordon A
Published: April 2008

The operation of continuously stirred tank bioreactors (CSTBs) at minimum cost is a major concern of operators. In this work, a CSTB design strategy is presented where impeller stirring speed and aeration rate are optimized to meet the oxygen demand of growing cells, simultaneously minimizing the capital and operating cost. The operating cost is limited to the cost of utilities. The optimization scheme assumes a given fermentor tank size, and that the properties of the culture medium and the oxygen respiratory requirements of the microorganisms being cultivated are known. It is possible to choose between two different turbine impellers during the design process. The equations, constraints, and the CSTB design strategy employed by the program are described. The effect of microbial species, ions in the culture medium, impeller style, as well as changing CSTB size and biomass input density on the optimum operating conditions, is examined. The mass transfer coefficient, gas holdup, mixing speed, and aeration rate are all reported at optimized cost conditions. A study of the effects of various parameters on the CSTB design are shown.
Dynamic Behaviour of a Continuous Heat Exchanger/Reactor after Flow Failure
Authors: Benaissa Wassila , Elgue Sebastien , Gabas Nadine , Cabassud Michel , Carson Douglas , Demissy Michel
Published: April 2008

The intensified technologies offer new prospects for the development of hazardous chemical syntheses in safer conditions: the idea is to reduce the reaction volume by increasing the thermal performances and preferring the continuous mode to the batch one. In particular, the Open Plate Reactor (OPR) type ``reactor/exchanger" also including a modular block structure, matches these characteristics perfectly. The aim of this paper is to study the OPR behaviour during a normal operation, that is to say, after a stoppage of the circulation of the cooling fluid. So, an experiment was carried out, taking the oxidation of sodium thiosulfate with hydrogen peroxide as an example. The results obtained, in particular with regard to the evolution of the temperature profiles of the reaction medium as a function of time along the apparatus, are compared with those predicted by a dynamic simulator of the OPR. So, the average heat transfer coefficient regarding the ``utility" fluid is evaluated in conductive and natural convection modes, and then integrated in the simulator. The conclusion of this study is that, during a cooling failure, a heat transfer by natural convection would be added to the conduction, which contributes to the intrinsically safer character of the apparatus.
Better that the Fed Regulates Subprime Mortgages
Authors: Hahn Robert , Passell Peter
Published: April 2008

Washington's efforts at limiting the fallout from the subprime mortgage mess generally deserve poor marks. But the Federal Reserve's proposed regulation of these mortgages is a step in the right direction.
Letter: Magin Begs Liberals to Think Twice about Social Security Privatization--I Say, "Think Thrice"
Authors: Serlin Richard H.
Published: April 2008

Richard Serlin questions whether returns would really be abnormally high for privatized social security accounts.
Operation and Control of a DVR in the Presence of Interharmonics
Authors: Jindal Amit Kumar , Ghosh Arindam , Joshi Avinash
Published: April 2008

The paper discusses the operating principles and control characteristics of a dynamic voltage restorer (DVR). It is assumed that the source voltages contain interharmonic components in addition to fundamental components. The main aim of the DVR is to produce a set of clean balanced sinusoidal voltages across the load terminals irrespective of unbalance, distortion and voltage sag/swell in the supply voltage. An algorithm has been discussed for extracting fundamental phasor sequence components from the samples of three-phase voltages or current waveforms having integer harmonics and interharmonics. The DVR operation based on extracted components is demonstrated. The switching signal is generated using a deadbeat controller. It has been shown that the DVR is able to compensate these interharmonic components such that the load voltages are perfectly regulated. The DVR operation under deep voltage sag is also discussed. The proposed DVR operation is verified through the computer simulation studies using the MATLAB software package.
Theory of Deterrence and Individual Behavior. Can Lawsuits Control File Sharing on the Internet?
Authors: Oksanen Ville , Välimäki Mikko
Published: April 2008

The music and movie industries have recently added individual consumers as the target of the file sharing lawsuits. It is often questioned why the industries use substantial resources to fight in the courtrooms instead of making better and more affordable products. In this article, we first analyze the reasons of the industry behavior suggesting that the court strategy may be in fact more effective, at least in the short term, than it should be based on pure economic calculations. However, the empirical evidence seems to imply that lawsuits fail to send a strong signal to individuals about the society’s supposedly negative attitude towards file sharing. General deterrence from the threat of being sued does not help in the end either because people are risk seeking in the face of making a decision between a certain and probable loss. In conclusion, we argue that the court strategy cannot be used to establish any social norm with a long lasting effect on individual behavior as long as the peer pressure works towards the opposite direction.
Dynamic Model for Polyethylene Production in a Multizone Circulating Reactor
Authors: Ghasem Nayef M. , Ang Wee-Lee , Hussain Mohamed Azlan
Published: April 2008

The multizone circulating reactor (MZCR) technology is a newly announced reactor design for solid-catalyzed gas-phase polymerization. The process is characterized by two hydrodynamically distinct but interconnecting polymerization zones, thus forming a continuous loop of polymer flow between the said zones. In the present study, a dynamic model for the MZCR reactor is developed to illustrate the basic dynamic behavior of the new reactor design; the model is used to study the copolymerization of ethylene with butene. Several parameter sensitivity analyses are performed to show the computer-simulated time responses for reactor temperature, number-average molecular weight, weight-average molecular weight, catalyst feed rate and the monomer concentration along the reactor length.
The Inheritance of Educational Inequality: International Comparisons and Fifty-Year Trends
Authors: Hertz Tom , Jayasundera Tamara , Piraino Patrizio , Selcuk Sibel , Smith Nicole , Verashchagina Alina
Published: April 2008

This paper estimates 50-year trends in the intergenerational persistence of educational attainment for a sample of 42 nations around the globe. Large regional differences in educational persistence are documented, with Latin America displaying the highest intergenerational correlations, and the Nordic countries the lowest. We also demonstrate that the global average correlation between parent and child's schooling has held steady at about 0.4 for the past fifty years.