bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficient Use of Materials and Energy
Authors: Thomas Valerie M.
Published: January 2011

The efficient use of materials and energy is at the core of energy and environmental challenges. At the company level, environmentally preferable supply chains is a key area in which operations research can make significant contributions. At the global level, key challenges relate to the dynamics of technology, economics, and environmental impacts, including the potential for material and energy efficiency, the relation of technological and economic development to changes in consumption patterns, and the potential for technology to reduce environmental impacts and constraints.
Feature Extraction and Feature Selection: A Survey of Methods in Industrial Applications
Authors: Anzanello Michel J.
Published: January 2011

In industrial processes, the handling of large amounts of data collected by sensors and computers has challenged engineers and practitioners, making feature selection a subject of massive research in academy and industry. The use of redundant, irrelevant, and noisy features (also known as variables) tends to spoil the performance of many statistical tools, leading to unreliable inferences and costly data collection. In this article we present a survey on variable selection methods and applications in the manufacturing and chemometrics field. We deploy these methods in two major classes: variable selection for prediction and for classification. We then briefly suggest future developments on the topic.
Fictitious Play Algorithm
Authors: Zafra Pablo
Published: January 2011

The original fictitious play algorithm is an iterative procedure developed by G. Brown to find an estimate of a solution to two‐person zero‐sum games (also commonly referred to as
matrix games
). The simplicity of the method is very appealing, but the convergence is very slow. Since its development, most of the ensuing research had focused on modifications to speed up convergence rate, identifying other classes of games where the method (or its variants) converges or fails to converge, and implementing the fictitious play concept in solving some applied problems. A complete description of the algorithm is provided, along with an example where a detailed step‐by‐step execution of the first few iterations is illustrated.
Generating Nonhomogeneous Poisson Processes
Authors: Pasupathy Raghu
Published: January 2011

We present an overview of existing methods to generate pseudorandom numbers from homogeneous Poisson processes. We provide three well‐known definitions of the homogeneous Poisson process, present results that form the basis of various existing generation algorithms, and provide algorithm listings. With the intent of guiding users seeking an appropriate algorithm for a given setting, we note the computationally burdensome operations within each algorithm. Our treatment includes one‐dimensional and two‐dimensional homogeneous Poisson processes.
Hazardous Materials Transportation
Authors: Verter Vedat
Published: January 2011

Significant volumes of dangerous goods are transported by road, rail, and marine shipments. Accidental release of this cargo can be harmful to humans and the environment. Governments at different levels are responsible for protecting the public and the environment from the undesirable consequences of hazardous materials transportation. This introductory article provides a brief overview of the state of the art in hazardous materials transportation. To this end, the alternative transport modes for dangerous goods are discussed, the prevailing methodologies for transport risk assessment are highlighted and the risk mitigation policies available for regulators are underlined. The article also emphasizes that the transportation of hazardous materials through urban areas as well as the use of intermodal transport networks for dangerous goods shipments constitute two potentially fruitful avenues for future research.
Hyper‐Heuristics
Authors: Kendall Graham , Burke Edmund K.
Published: January 2011

This article provides an introduction to hyperheuristics, the origins of which can be traced back to the 1960s. There was a significant increase in research interest from about 2000. Hyperheuristics can be seen as eitherheuristics to choose heuristics or as heuristics to generate heuristics.

In contrast to most uses of metaheuristics, which usually search the solution space directly, hyperheuristics search over a heuristic space. One motivation of the area is that, by operating in this way it might be possible to raise the level of generality of search algorithms so that they can address a broader spectrum of problems (without human adaptation) than is possible today. Another long‐term aim of hyperheuristic research is to build search methodologies that are able to automatically adapt themselves to different problem instances/domains with as little human input as possible.

This article provides access to relevant literature, in addition to providing a brief history of the area and describing the two approaches (selection of heuristics and generating heuristics) mentioned above. It is intended as a brief and initial introduction to the area.
Infinite Horizon Problems
Authors: Ghate Archis
Published: January 2011

The systems under consideration in (discrete‐time) sequential decision problems in operations research and the management sciences often do not have a predetermined time of extinction. Incorporating an arbitrary finite horizon can therefore introduce end‐of‐study distortions in early decisions. Such problems are therefore typically modeled over an unbounded horizon. A majority of the work in this area focuses on stationary models, which assume that the problem data do not change over time. There is also a considerable body of research on nonstationary problems. We briefly review some of the key concepts in nonstationary infinite horizon sequential decision making problems.
Information Sharing in Supply Chains
Authors: Ren Zhong Justin
Published: January 2011

This article reviews supply chain literature on information sharing. We first provide an overview of different types of information existing in a supply chain. Then we survey literature, both analytical and empirical, on each. Finally, we conclude with some thoughts on future research.
Interior‐Point Linear Programming Solvers
Authors: Benson Hande Y.
Published: January 2011

We present an overview of available software for solving linear programming problems using interior‐point methods. Some of the codes discussed include primal and dual simplex solvers as well, but we focus the discussion on the implementation of the interior‐point solver. For each solver, we present types of problems solved, available distribution modes, input formats and modeling languages, as well as algorithmic details, including problem formulation, use of higher corrections, presolve techniques, ordering heuristics for symbolic Cholesky factorization, and the specifics of numerical factorization.
Klimov'sModel
Authors: Niño‐Mora José
Published: January 2011

The Klimov model concerns the optimal dynamic scheduling of a multiclass M/G/1 queue with general Bernoulli feedback of jobs and linear holding costs. In his seminal 1974 paper, Klimov established the optimality of a static priority‐index rule for such a model under the average cost criterion and gave an adaptive‐greedy index algorithm, via a novel linear programming approach. The model has rich and insightful connections with stochastic scheduling and bandit problems, and has found use in a wide variety of applications, most notably in time‐sharing computer‐communication and flexible manufacturing systems.
Location (Hotelling) Games and Applications
Authors: Brenner Steffen
Published: January 2011

This article provides an introduction into the Hotelling literature of spatial and product differentiation. We examine the impact of the market structure on price competition and equilibrium differentiation. We find that spatial differentiation is not uniformly high or low but depends on a number of market parameters such as transport costs, demand elasticity, number of firms, and density of consumers, among others.
Managing Product Introductions and Transitions
Authors: Bílgíner Özlem , Erhun Feryal
Published: January 2011

As the rate of innovation increases, companies face expanding product lines, shorter product lifecycles, and more frequent product transitions, all of which can bring tremendous value but also pose enormous challenges. In this article, we provide a brief introduction to and survey of product introductions and transitions. We discuss supply and demand factors that must be considered for a successful product launch. Dynamics of a product launch depend primarily on how demand is generated. Of the various theories which explain demand generation, new product diffusion theory is among the most commonly used. Thus, we also provide a brief introduction to new product diffusion models. We conclude with potential research directions.
Managing
R
&
D
and Risky Projects
Authors: Cox Louis Anthony
Published: January 2011

This article discusses quantitative concepts and methods for making risk management decisions about R&D and other uncertain projects. Such decisions include what projects to fund, the order in which to attempt different activities within a project, when to abandon projects that are not working out as hoped, and how to structure the incentives of project managers and investors to take best advantage of the opportunities represented by risky projects.
Manufacturing Facility Design and Layout
Authors: Heragu Sunderesh S. , Ekren Banu Y.
Published: January 2011

In this article, we introduce the manufacturing facility design and layout problem and discuss the characteristics and types of next‐generation factory layouts and the need for a stochastic analysis of layout and facility design problems.
Measures of Risk Equity
Authors: Keller L. Robin , Feng Tianjun , Wang Yitong
Published: January 2011

This article covers measures of fairness or equity for situations involving risk, as represented with a probability distribution over outcomes, which often include adverse health or safety outcomes.
MILPSoftware
Authors: Linderoth Jeffrey T. , Lodi Andrea
Published: January 2011

In this article, we give a brief overview of state‐of‐the‐art software for the solution of mixed‐integer linear programs (MILP). We begin with a brief description of important algorithmic features and conclude with concise individual descriptions of software packages.
Minimum Cost Flows
Authors: Vaidyanathan Balachandran , Ahuja Ravindra K.
Published: January 2011

The minimum cost flow problem is a fundamental network flow problem. The objective of this problem is to determine the minimum cost method of transporting units of a goods that originates at one or more points in a network (sources or supplies), with arc capacities to one or more demand points in the network (sinks or demands). In this article we introduce the minimum cost flow problem and its applications, describe the conditions for a feasible flow to be optimal, and discuss three classical algorithms to solve it.
Operational Research Society of India
Authors: Sinha Bani K.
Published: January 2011

The Operational Research Society of India (ORSI) is a national forum set up with the objective of promoting the education and applications of operational research (OR) in business, industry, and other organizations, and also to improve the quality of human life. It was established in 1957. The Society is one of the earliest members of the International Federation of Operational Research Societies (IFORS) and it is the first developing country to have become a member of IFORS.
Operational Risk
Authors: Coleman Rodney
Published: January 2011

Operational risk is the business risk of loss resulting from inadequate or failed internal processes, people, systems, or from external events. Fraud, accounting errors, equipment failure or theft, mis‐selling, product flaws, claims for unfair dismissal: all are business costs not attributable to a business's strategic aims. Serious operational risk events also occur beyond a purely business setting: for example, in hospitals, manufacturing plants, ship building, nuclear power generation, offshore drilling, warfare, and from disruption caused by natural disasters. The methods of management, monitoring, modeling, measuring, and mitigation of operational risk are reviewed, illustrated with data taken mainly from banking and insurance.
Operations Research and Management Science in Fire Safety
Authors: Watts John M.
Published: January 2011

Like OR/MS, fire safety incorporates many different types of problems: sociological, technical, and managerial. This article describes some of the broad areas of fire safety that have been the subject of OR/MS work or that have potential for application. These areas include wildland fires, process industries, and fire safety in buildings. A detailed example of the use of OR/MS tools and techniques in the development of a fire risk index for buildings is presented. It is concluded that fire safety provides unique challenges that await the more sophisticated OR/MS practitioner.
Optimization Models for Cancer Treatment Planning
Authors: Cao Wenhua , Lim Gino J.
Published: January 2011

Operations research techniques have been significantly utilized in the practice of cancer treatment planning in order to deliver more efficient and precise treatments to patients. This article is designed to introduce recent advances in the treatment planning optimization for external radiation therapy, internal radiation therapy (brachytherapy), and chemotherapy. The main focus will be on gamma knife radiosurgery, conventional three‐dimensional radiotherapy (3DCRT), intensity‐modulated radiation therapy (IMRT), and proton therapy. Problem formulations and optimization models for each treatment type are discussed.
Overweighting of Small Probabilities
Authors: Burns Zach , Chiu Andrew , Wu George
Published: January 2011

The psychological impact of a low probability or rare event is typically large relative to that of the event's actuarial likelihood. Thisoverweightingfollows a two‐stage process. First, rare events tend to be overestimated because of the availability heuristic, anchoring on the “ignorance prior,” and coarse chance categories. Second, when making decisions, low probability events are overweighted because of the “possibility effect”—decision makers are more sensitive to probability changes close to 0 than to probability changes away from 0.
Spanish Society of Statistics and Operations Research
Authors: Garcia Jurado Ignacio
Published: January 2011

In this note we present a brief history of SEIO, the Spanish Society of Statistics and Operations Research. We also explain its functional structure and other relevant features of its current life.
Supply Chain Scheduling: Origins and Application to Sequencing, Batching and Lot Sizing
Authors: Hall Nicholas G.
Published: January 2011

Research on supply chains has focused mainly on the coordination of strategic decisions, whereas operational issues have been studied much less. However, the coordination of operational decisions is often important, especially for time‐sensitive, customized, and made‐to‐order products. The topic of this article, supply chain scheduling, is the study of the coordination of operational decisions, including scheduling, among supply chain partners with conflicting objectives. Supply chain scheduling uses short planning horizons with reliable data, optimization of decisions, and the exact evaluation of coordination issues. This article discusses the origins of supply chain scheduling, and their relationship to other modern extensions of classical scheduling theory, including multicriteria scheduling, integrated scheduling and sequencing games. Specific examples of supply chain scheduling are discussed for the coordination of scheduling, batching, and lot‐sizing decisions. Various methodologies within supply chain scheduling evaluate both the conflict between supply chain partners and also the benefit to overall supply chain performance from cooperation. The design of incentives and game theory solutions that promote cooperation is an important prescriptive feature of this rapidly evolving research area.
Travel Demand Modeling
Authors: Southworth Frank , Garrow Laurie A.
Published: January 2011

This chapter describes the principal types of both passenger and freight demand models in use today, providing a brief history of model development supported by references to a number of popular texts on the subject, and directing the reader to papers covering some of the more recent technical developments in the area. Over the past half century, a variety of methods have been used to estimate and forecast travel demands, drawing concepts from economic/utility maximization theory, transportation system optimization, and spatial interaction theory, using and often combining solution techniques as varied as Box–Jenkins methods, nonlinear multivariate regression, nonlinear mathematical programming, and agent‐based microsimulation.
Trust
Authors: Godfrey Robert
Published: January 2011

This article is a review of the many varied approaches to the study of trust, with more specific applications to the domains of risk, risk management, risk perception, and risk communication.
Iranian Operations Research Society (IORS)
Authors: Mahdavi‐Amiri Nezam
Published: January 2011

We describe the Iranian Operations Research Society (IORS), established in 2005 and joined IFORS in 2009, by explaining its goals, identifying the members of its first two executive councils, announcing its Iranian Journal of Operations Research (IJOR), and pronouncing its annual International Conferences in Operations Research.
Public Health, Emergency Response, and Medical Preparedness I: Medical Surge
Authors: Lee Eva K. , Yang Anna Yang , Pietz Ferdinand , Benecke Bernard
Published: January 2011

Medical surge forms the cornerstone of preparedness planning efforts for major medical incidents. Surge capacity encompasses multidimensional aspects such as potential patient beds; available space in which patients may be triaged, managed, vaccinated, decontaminated, or simply located; available care personnel of all types; necessary medications, supplies, and equipment; and even the legal capacity to deliver health care under situations that exceed authorized capacity. Further, close collaboration between public health and health care facilities is very important to effective disaster response. In the aftermath of the September 11 terrorist attacks and the dissemination of anthrax in 2001, the ability of the US health care system to provide an effective and coordinated response to mass casualty or complex incidents came under intense scrutiny. More recently, the devastation caused by Hurricane Katrina and the mass disruption of public health and medical services along the Gulf Coast spotlighted the need for cohesive strategies that focus on management systems for major public health and medical response. In this article, we explore hospital surge capacity planning. Specifically, we will discuss issues related to surge patterns, the interplay of care personnel and staff, facilities, equipment and supplies, and incident management system. Approaches used in balancing daily operational efficiency versus maintaining an appropriate surge capacity will be discussed, and the importance of international collaboration is highlighted. Further, OR methodologies, including simulation, optimization, stochastic processes and systems dynamics models used in medical surge analysis will be briefly reviewed.
Vibrational Circular Dichroism: Ensuring Quality of Pharmaceutical Products
Authors: Tsankov Dimiter , Polyanichko Alexander , Wieser Helmut
Published: January 2011

The interest in Vibrational Circular Dichroism (VCD) has grown at a good pace during last few years. This technique provides a detailed description of progress in vibrational optical activity for determining structural properties of pharmaceuticals. Now highly advanced VCD spectrometers are available which implement the dual polarization modulation method. This article focuses on instrumental methods, unique applicabilities and capabilities, review of scientific applications such as enantiomeric purity and absolute configuration, solution conformations, pharmaceuticals, and natural products and concludes with an assessment of the instrumentation's utility, when metal ions play significant roles in biological and medicinal processes. The study finds that same metal ions significantly affect large molecular biological complexes that arise from the interactions of DNA, proteins, and medicinal drugs.
Multicentre prospective study of fascial closure rate after open abdomen with vacuum and mesh-mediated fascial traction
Authors: Acosta S , Bjarnason T , Petersson U , Pålsson B , Wanhainen A , Svensson M , Djavani K , Björck M
Published: January 2011

Background

Damage control surgery and temporary open abdomen (OA) have been adopted widely, in both trauma and non-trauma situations. Several techniques for temporary abdominal closure have been developed. The main objective of this study was to evaluate the fascial closure rate in patients after vacuum-assisted wound closure and mesh-mediated fascial traction (VAWCM) for long-term OA treatment, and to describe complications.

Methods

This prospective study included all patients who received VAWCM treatment between 2006 and 2009 at four hospitals. Patients with anticipated OA treatment for fewer than 5 days and those with non-midline incisions were excluded.

Results

Among 151 patients treated with an OA, 111 received VAWCM treatment. Median age was 68 years. Median OA treatment time was 14 days. Main disease aetiologies were vascular (45 patients), visceral surgical disease (57) and trauma (9). The fascial closure rate was 76·6 per cent in intention-to-treat analysis and 89 per cent in per-protocol analysis. Eight patients developed an intestinal fistula, of whom seven had intestinal ischaemia. Intestinal fistula was an independent factor associated with failure of fascial closure (odds ratio (OR) 8·55, 95 per cent confidence interval 1·47 to 49·72; P = 0·017). The in-hospital mortality rate was 29·7 per cent. Age (OR 1·21, 1·02 to 1·43; P = 0·027) and failure of fascial closure (OR 44·50, 1·13 to 1748·52; P = 0·043) were independently associated with in-hospital mortality.

Conclusion

The VAWCM method provided a high fascial closure rate after long-term treatment of OA. Technique-related complications were few. No patient was left with a large planned ventral hernia.
A finite element method for a microstructure‐based model of blood
Authors: Iolov Alexandre , Kane Abdoulaye S. , Bourgault Yves , Owens Robert G. , Fortin André
Published: January 2011

This paper presents the first flows computed in non‐trivial geometries while accounting for the contribution of the red cells to the Cauchy stress using the haemorheological model of Owens and Fang (it J. Non‐Newtonian Fluid Mech. 2006; 140:57–70; Biorheology 2006; 43:637–660). In this model, the local shear viscosity is determined in terms of both the local shear‐rate and the average rouleau size, with the latter being the solution of an advection‐reaction equation. The model describes the viscoelastic, shear‐thinning and hysteresis behaviour of flowing blood, and includes non‐local effects in the determination of the blood viscosity and stresses. This rheological model is first briefly derived. A finite element method is next presented, extending the DEVSS method of Fortin and coworkers (Comput. Methods Appl. Mech. Engrg. 2000; 189:121–139; J. Non‐Newtonian Fluid Mech. 1995; 60:27–52; Comput. Methods Appl. Mech. Engrg. 1997; 143:79–95) to the solution of this Oldroyd‐B type model but with a non‐constant Deborah number. A streamline upwind Petrov–Galerkin approach is also adopted in the discretization of the constitutive equation and the microstructure evolution equation. The numerical results presented begin with validation of our finite element scheme in a coaxial rheometer both for a prescribed homogeneous velocity field and for a fully two‐dimensional calculation including the solution of the linear momentum equation. The consideration of blood flow in a straight channel allows us to test convergence of our numerical scheme. Finally, we present results for an aneurytic channel under both steady and pulsatile flow conditions. Comparisons are made with the results from an equivalent Newtonian fluid. Our choice of material parameters leads to only weakly elastic effects but noticeable differences are seen between the Newtonian and non‐Newtonian flows, especially in the pulsating case. Copyright © 2011 John Wiley & Sons, Ltd.
An open and scalable architecture for delivering 3D shared visualization services to heterogeneous devices
Authors: Paravati Gianluca , Sanna Andrea , Lamberti Fabrizio , Ciminiera Luigi
Published: January 2011

Shared visualization environments represent an effective means to enhance collaborative work in engineering and scientific design tasks. The availability of high‐speed networks allows researchers to work together from geographically distributed locations, and mobile devices are able to carry out ubiquitous 3D visualization tasks through wireless network connections. This paper presents a scalable architecture for the delivery of shared 3D visualization services to heterogeneous terminals ranging from powerful workstations to mobile devices such as PDAs and smart‐phones. The framework design allows both desktop and mobile clients to simultaneously visualize the same model by sharing a common view. Remote‐rendering servers support effective visualization on thin clients, and a load balancing mechanism provides efficient resource usage. Copyright © 2011 John Wiley & Sons, Ltd.
Surface Chemistry and Interfacial Charge‐Transfer Mechanisms in Photoinduced Oxygen Exchange at O2–TiO2 Interfaces
Authors: Montoya Juan Felipe , Peral José , Salvador Pedro
Published: January 2011

Experimental results obtained over the last three decades on photoinduced oxygen isotopic exchange (POIE) of TiO2 oxygen atoms with those of adsorbed water molecules and gaseous O2 are analyzed in the light of recent information from the literature on the interaction of water and O2 species with the TiO2 surface (obtained by application of surface spectroscopy techniques in combination with high‐resolution scanning tunnelling microscopy). The analysis emphasizes the singular role that bridging oxygen ions and bridging oxygen vacancies play in TiO2 surface chemistry and interfacial electron transfer at the gas phase–TiO2 interface in the absence and presence of water. The observed competition between POIE and the photo‐oxidation (PO) of organic compounds is analyzed in terms of the recently developed direct‐indirect (D‐I) kinetic model for heterogeneous photocatalysis (D. Monllor‐Satoca et al., Catal. Today, 2007, 129, 247, and references therein).
Stability and Dynamics of Cyclic Diguanylic Acid in Solution
Authors: Zhang Lixian , Meuwly Markus
Published: January 2011

Cyclic diguanylic acid (CDG) is a ubiquitous messenger involved in bacterial signaling networks. Despite its central role in motility, biofilm formation, virulence, and flagellum development, fundamental properties such as its aggregation state are still poorly understood. Here the dynamics and stability of metal‐free and Mg2+‐bound CDG are characterized. Atomistic simulations establish that the CDG dimer is slightly favored (by −5 kcal mol−1) over its dissociated form (2 CDG), while the Mg2+ ion coordinated in the X‐ray structure readily dissociates from (CDG)2 in solution and prefers water coordination. As a ligand in a protein, CDG binds both as a U‐shaped and a quasilinear monomer. The current results indicate that the energy difference between these two conformations is only a few kilocalories per mole, which explains the facile adaptation to different protein environments. This, together with the slight preference of (CDG)2 over 2 CDG suggests that (CDG)2 binding to a protein does probably not occur via sequential binding of two individual monomers.
Diving Mammals
Authors: Ponganis Paul J.
Published: January 2011

The ability of diving mammals to forage at depth on a breath hold of air is dependent on gas exchange, both in the lung and in peripheral tissues. Anatomical and physiological adaptations in the respiratory system, cardiovascular system, blood and peripheral tissues contribute to the remarkable breath‐hold capacities of these animals. The end results of these adaptations include efficient ventilation, enhanced oxygen storage, regulated transport and delivery of respiratory gases, extreme hypoxemic/ischemic tolerance, and pressure tolerance. © 2011 American Physiological Society.Compr Physiol1:447‐465, 2011.
Microgravity
Authors: Prisk G. Kim
Published: January 2011

Gravity profoundly affects the overall mechanics of the respiratory system. Functional residual capacity, when measured in sustained microgravity, is intermediate to that present in the standing and supine postures in 1G, consistent with early modeling studies. This change occurs almost exclusively through changes in the abdominal compliance and thus in the volume of the abdominal compartment, with the rib cage being relatively unaffected by gravity. Microgravity leaves vital capacity unaltered once the initial translocation of blood into the thorax is corrected by homeostatic mechanisms, but residual volume is reduced, likely through a more uniform distribution of alveolar size permitting deflation to a lower overall lung volume. Expiratory flows are unaffected by microgravity provided they are measured following normalization of the intrathoracic blood volume. During sleep in microgravity, there is an almost complete abolition of obstructive sleep apnea events. © 2011 American Physiological Society.Compr Physiol1:485‐497, 2011.
Analysis and effective controller design for the cascaded H‐bridge multilevel APF with adaptive signal processing algorithms
Authors: Xu Lin , Han Yang , Khan M. M. , Pan Jun‐Min , Chen Chen , Yao Gang , Zhou Li‐Dan
Published: January 2011

The cascaded H‐bridge (CHB) multilevel inverter is being recognized as the most suitable topology for high‐power medium‐voltage power quality conditioning applications. This paper presents mathematical modeling and effective controller design methodology for the CHB‐based active power filters (APFs), which achieves dynamic reactive power and harmonic compensation. The most crucial problems in CHB‐APF control are the simultaneous requirements of both accurate harmonic current compensation and the dc‐link voltage stabilization among the H‐bridges, which is the prerequisite for the stable operation of CHB‐APF. To achieve dc‐link stabilization, a novel voltage balancing algorithm is proposed by splitting the dc‐link voltage control task into two parts, namely, the average voltage control and the voltage balancing control, where the sine and cosine functions of the phase angle of the fundamental component of the grid voltage are used, respectively. To ensure accurate phase tracking, a novel phase‐locked loop (PLL) is proposed by using the adaptive linear neural network (ADALINE), where the grid voltage background distortion is also taken into account. The superior performance of the ADALINE‐PLL is validated by comparison with the existing PLLs in literatures. Furthermore, the proportional‐resonant (PR) controller is used for the reference current tracking. A separate ADALINE algorithm is applied for reference current generation (RCG) for the CHB‐APF. The excellent performance of the ADALINE‐based RCG scheme is verified by comparison with the existing RCG schemes, namely, the low‐pass filter approach and the single‐phase p − qmethod. The experimental results on the three modules CHB‐APF are presented, which verifies the effectiveness of the proposed control algorithms. Copyright © 2011 John Wiley & Sons, Ltd.
Ecohydrology of dry regions of the United States: water balance consequences of small precipitation events
Authors: Lauenroth William K. , Bradford John B.
Published: January 2011

Small precipitation events (≤5 mm) are a key component of the precipitation regimes of dry regions in the United States. Understanding their importance is useful, but exploring their significance for water balance processes is of utmost consequence for our knowledge about the functioning of ecosystems and their responses to climate change. Our objective was to evaluate the implications of precipitation event size distributions for the partitioning of water loss between evaporation and transpiration and for the number of days with wet soil. We used sites from the Great Plains of the United States to provide long‐term weather data for our simulation analyses. Our simulations varied distributions of precipitation event size and potential evapotranspiration (PET) for two contrasting soils: a sandy loam with low water holding capacity and a silt loam with high water holding capacity. Event size and specifically the numerical importance of the smallest size (0–5 mm) was the most important control on our results. Soil water holding capacity and PET were important modifiers of the responses. The ratio of evaporation to actual evapotranspiration (E/AET) increased as the percentage of small events increased and as PET increased. E/AET was greater for all combinations of event size and PET for the silt loam than for the sandy loam soils. The number of days with wet soil decreased as small events and PET increased. Our results suggest that the number of small events is one of the most important controls on water balance processes in arid and semiarid regions. Copyright © 2011 John Wiley & Sons, Ltd.
Multi‐hazard upgrade decision making for critical infrastructure based on life‐cycle cost criteria
Authors: Jalayer F. , Asprone D. , Prota A. , Manfredi G.
Published: January 2011

The life‐cycle cost can be regarded as a benchmark variable in decision making problems involving the retrofit and upgrading of existing structures. A critical infrastructure is often subjected to more than one hazard during its lifetime. Therefore, the problem of evaluating the life‐cycle cost involves uncertainties in both loading and structural modeling parameters. The present study is a preliminary study aiming to calculate the expected life‐cycle cost for a critical infrastructure subjected to more than one hazard in its service lifetime. A methodology is presented that takes into account both the uncertainty in the occurrence of future events due to different types of hazard and also the deterioration of the structure as a result of a series of events. In order to satisfy life safety conditions, the probability of exceeding the limit state of collapse is constrained to be smaller than an allowable threshold. Finally, the methodology is implemented in an illustrative numerical example which considers a structure subjected to both seismic hazard and blast hazard in both upgraded and non‐upgraded configurations. It is demonstrated how expected life‐cycle cost can be used as a criterion to distinguish between the two choices while satisfying the life safety constraint. Copyright © 2011 John Wiley & Sons, Ltd.
Analysis of the gene expression pattern of bovine blastocysts at three stages of development
Authors: Rekik Wiem , Dufort Isabelle , Sirard Marc‐André
Published: January 2011

Blastocyst formation is a primordial event of pre‐implantation development since it is required for pregnancy establishment and progression. The blastocyst plays a pivotal role because it is the stage at which the embryo starts coordinated cross‐talk with the mother. It is also the terminal step before transfer in bovine; it reflects all stresses the embryo may have faced during the process of in vitro treatment. Achieving the formation of a morphologically healthy blastocyst following normal kinetics is good, but remains a poor indicator of embryo quality. Considering the limitation of the invasive methods for competence assessment, the analysis of blastocysts' gene expression is a promising way to improve our understanding of blastocyst formation and to study the effects of different treatments on gene expression. To that end, early, expanded, and hatched blastocysts, derived from in vitro fertilization and culture, were collected for RNA extraction, amplification, and cDNA microarray hybridization. Gene candidates (IFNt, PLAC8, SSLP1, AKR1B1, HNRNPA2B1, ARGFX, NANOS, CCNB1) were selected and confirmed using real‐time RT‐PCR to validate the microarray data. Our analysis showed that hatched blastocysts are enriched in transcripts implicated in attachment, cell adhesion, and extracellular matrix digestion. Early blastocysts expressed genes mainly involved in cell cycle control, transcription, and translation. Real‐time RT‐PCR validated most microarray results (87.5%). Overall, our study provides new insights into the molecular regulation of blastocyst formation. In addition, it could help assess blastocyst staging and select better embryos based on the expression of quality markers. Mol. Reprod. Dev. 78:226–240, 2011. © 2011 Wiley‐Liss, Inc.
Simplified analytical solution for point load acting behind a cantilever wall
Authors: Iskander George Maurice
Published: January 2011

The analysis of earth pressure resulting from an applied point load behind a retaining wall is to be carried out in three dimensions as the earth pressure distribution varies both in vertical and horizontal directions. In this research, the semi‐empirical expressions developed by Terzaghi [Trans. ASCE1954;119] for earth pressure due to point load are integrated and a correction factor is introduced to develop equivalent equations for two‐dimensional analyses. A new parameter referred to as the design width, which is the horizontal distance retained by the individual vertical retaining element is introduced. The used procedure and the resulted equations are tested and verified by adopting different design width values covering the practical range. The resulted equations together with the semi‐empirical expressions of earth pressure due to line load developed by Terzaghi [Trans. ASCE1954;119] can be easily used for two‐dimensional analysis of the effect of point load. Copyright © 2011 John Wiley & Sons, Ltd.
“Nothing works!” A case study using cognitive‐behavioral interventions to engage parents, educators, and children in the management of attention‐deficit/hyperactivity disorder
Authors: Levine Eva S. , Anshel Daphne J.
Published: January 2011

Attention‐deficit/hyperactivity disorder (ADHD) remains one of the most prevalent mental health diagnoses identified in school‐age children. Affected children show an increased risk for school failure, social difficulties, and the development of psychiatric comorbidities. Despite the availability of evidence‐based behavioral protocols for managing ADHD‐related impairments, school psychologists often encounter difficulties involving teaching staff and parents in the sustained implementation of these interventions. Cognitive‐behavioral therapy (CBT) can address treatment obstacles through emphasizing psychoeducation, the development of a collaborative treatment context, and the identification of thoughts and assumptions that maintain maladaptive behavior patterns. This article presents a case study of Alex, an 8‐year‐old child with ADHD. The school psychologist treating Alex supplemented standard contingency management training with parent‐, teacher‐, and child‐focused CBT strategies. This case study outlines a central role for CBT in school‐based ADHD management. © 2011 Wiley Periodicals, Inc.
Parent feedback conferences: An opportunity to intervene?
Authors: Flanagan Rosemary
Published: January 2011

School personnel and parents refer youth for psychoeducational evaluations for various reasons. At times, the data do not indicate difficulties that necessitate any level of special education services. That should not mean that the school psychologist's work is complete. Given that evaluation data can indicate a wide variety of issues, including ones that are indirectly related to the referral question, it seems appropriate for the school psychologist to be able to offer expertise on these related issues. In this article, a role for the school psychologist as an individual who could offer targeted intervention in a brief meeting is discussed. Some behavioral, affective, and interpersonal concerns of children and their families might be addressed in this manner, and of course, could be followed up or revisited readily. Cognitive and behavioral interventions are particularly suitable for this purpose. Thus, the school psychologist is in a unique position to provide assistance, which may be akin to single‐session psychotherapy. © 2011 Wiley Periodicals, Inc.
Charge inversion via concurrent cation and anion transfer: application to corticosteroids
Authors: Hassell Kerry M. , LeBlanc Yves , McLuckey Scott A.
Published: January 2011

A novel charge inversion process that involves the removal of an excess cation from an analyte ion and the transfer of an anion to the neutral analyte in a single ion/ion encounter is described. Polyamidoamine (PAMAM) half‐generation dendrimer anions that contain small anions, such as the chloride ion, were used as charge inversion reagents. Several competing processes can occur that include removal of the cation to neutralize the analyte, the removal of the excess cation and an additional proton to yield the deprotonated molecule, or removal of the excess cation and transfer of a small anion to the analyte. For the latter process to dominate, several requirements for both the reagent anion and the analyte cation must be met. The reagent anion must form multiply charged anions and must be able to incorporate one or more small anions for transfer. The analyte must have no strongly acidic sites as well as a relatively high affinity for small anion attachment. The PAMAM dendrimer anions must meet the conditions for the reagent anions and the cations of the corticosteroids meet the conditions for the analyte. The estrogenic steroid estrone, on the other hand, does not meet the requirements and, as a result, is largely neutralized when reacted with the reagent anions. This reaction, therefore, is highly selective and might serve as a useful reaction for the screening of appropriate analytes. Copyright © 2011 John Wiley & Sons, Ltd.
A quantitation method for mass spectrometry imaging
Authors: Koeniger Stormy L. , Talaty Nari , Luo Yanping , Ready Damien , Voorbach Martin , Seifert Terese , Cepa Steve , Fagerland Jane A. , Bouska Jennifer , Buck Wayne , Johnson Robert W. , Spanton Stephen
Published: January 2011

A new quantitation method for mass spectrometry imaging (MSI) with matrix‐assisted laser desorption/ionization (MALDI) has been developed. In this method, drug concentrations were determined by tissue homogenization of five 10 µm tissue sections adjacent to those analyzed by MSI. Drug levels in tissue extracts were measured by liquid chromatography coupled to tandem mass spectrometry (LC/MS/MS). The integrated MSI response was correlated to the LC/MS/MS drug concentrations to determine the amount of drug detected per MSI ion count. The study reported here evaluates olanzapine in liver tissue. Tissue samples containing a range of concentrations were created from liver harvested from rats administered a single dose of olanzapine at 0, 1, 4, 8, 16, 30, or 100 mg/kg. The liver samples were then analyzed by MALDI‐MSI and LC/MS/MS. The MALDI‐MSI and LC/MS/MS correlation was determined for tissue concentrations of ∼300 to 60 000 ng/g and yielded a linear relationship over two orders of magnitude (R2 = 0.9792). From this correlation, a conversion factor of 6.3 ± 0.23 fg/ion count was used to quantitate MSI responses at the pixel level (100 µm). The details of the method, its importance in pharmaceutical analysis, and the considerations necessary when implementing it are presented. Copyright © 2011 John Wiley & Sons, Ltd.
The Er71 Is an Important Regulator of Hematopoietic Stem Cells in Adult Mice
Authors: Lee Dongjun , Kim Tackhoon , Lim Dae-Sik
Published: January 2011

The Ets transcription factor Er71 is an important regulator of endothelial and hematopoietic development during mammalian embryogenesis. However, the role of Er71 in adult hematopoiesis has remained unknown. We now first show that conditional deletion of Er71 in the hematopoietic system of adult mice results in a marked reduction (55%) in the number of hematopoietic stem cells (HSCs) that is likely due to increased cell death. Bone marrow transplantation (BMT) experiments further confirmed that Er71 is required for repopulation of HSCs. In addition, Er71+/− mice exhibited a slight decrease (37%) in the number of HSCs than those of Er71+/+ mice, indicating that the function of Er71 in HSC maintenance is dependent on gene dosage. Moreover, Er71 was shown to be required for Tie2 expression, which contributes to HSC maintenance. Our results thus suggest the role of a single transcription factor in controlling HSCs through regulation of Tie2 expression in adult animals.
Retrofit of RC frames against progressive collapse using prestressing tendons
Authors: Kim Jinkoo , Shin Woo‐Seung
Published: January 2011

This study investigates the effect of prestressing tendons on the progressive collapse performance of a 6‐ and 20‐story reinforced concrete model structures. According to nonlinear static and dynamic analysis results, the analysis model structures turned out to be vulnerable to progressive collapse caused by sudden loss of a first story column. However, the RC structures reinforced by external prestressing tendons along floor girders showed stable behavior against progressive collapse. The retrofit effect increased as the initial tension and cross‐sectional area of tendons increased. The incremental dynamic analyses showed that the seismic performance of the model structure was also enhanced after the retrofit using tendons. Based on analysis results, it was concluded that the retrofit of existing buildings using prestressing tendons could be effective for increasing both progressive collapse resisting capacity and seismic performance of RC framed structures. Copyright © 2011 John Wiley & Sons, Ltd.
Manifold‐based canonical correlation analysis for wireless sensor network localization
Authors: Gu Jingjing , Chen Songcan
Published: January 2011

Signal‐strength‐based location estimation in wireless sensor networks is to locate the physical positions of unknown sensorsviathe received signal strengths. In this field, there are few localization researches sufficiently exploiting topology structures of the network in both signal space and physical space. The goal of this paper is to first establish two effective localization models based on specific manifold (or local) structures of both signal space and physical (location) space by using our previous locality preserving canonical correlation analysis (LPCCA) model and a newly‐proposed locality correlation analysis (LCA) model, and then develop their corresponding novel location algorithms, called location estimation—LPCCA (LE—LPCCA) and location estimation—LCA (LE—LCA). Since both LPCCA and LCA relatively sufficiently take into account locality characteristics of the manifold structures in both the spaces, our localization algorithms developed from them consequently achieve better localization accuracy than other publicly available advanced algorithms. Copyright © 2011 John Wiley & Sons, Ltd.
A link adaptation scheme for the downlink of mobile hotspot
Authors: Hasan Md. M. , Mark Jon W. , Shen X.
Published: January 2011

A link adaptation (LA) scheme for the downlink of mobile hotspot, which is supported by an IEEE 802.16e or mobile WiMAX network, is proposed. The mobile WiMAX uses orthogonal frequency division multiple access (OFDMA) in its physical layer. The main function of the LA scheme is to select an appropriate burst profile, which includes a multiple input multiple output (MIMO) transmission mode, modulation technique, and coding scheme. We formulate a discrete optimization problem for the LA scheme by maximizing the throughput. An algorithm to implement the LA scheme is also proposed. Numerical results show that the proposed LA scheme exhibits good performance. Copyright © 2011 John Wiley & Sons, Ltd.