bluuebunny/crossref_metadata_2025_split huggingface dataset:
The accuracy of linear theory for predicting mountain‐wave drag: Implications for parametrization schemes
Authors: Wells H. , Vosper S. B. 
Published: February 2010

AbstractThis study focuses on the accuracy of simple methods used in parametrization schemes for predicting the drag due to orographically excited gravity waves (mountain waves). Linear and nonlinear model simulations of flow over a long, low two‐dimensional ridge are used to evaluate the importance of internal wave reflection and nonlinearity. A long ridge with a small non‐dimensional mountain height and a gentle slope is used so that, in the absence of vertical variations in the background profile of wind and stability, the mountain‐wave drag is accurately predicted by linear theory. Simulations conducted for simple idealised profiles in which the background stability has a two‐layer (troposphere–stratosphere) structure show that whilst the drag is accurately predicted by linear solutions, interference effects due to partial wave reflection can alter the drag significantly. Estimates of the drag which are based solely on low‐level measurements of wind and stability, such as those in current operational mountain‐wave parametrizations, cannot account for this effect. Results from simulations based on more complex realistic profiles, obtained from both radiosondes and a forecast model, show that the linear and nonlinear drag predictions can differ significantly. This implies that linear solutions can be inaccurate even when they are calculated for the full atmospheric profile (rather than being based on low‐level average quantities). It is hypothesised that, in this case, the nonlinearity is due to resonant triad interactions which occur when there are oscillations in the Scorer parameter with a wavelength half that of the dominant vertically propagating mountain wave. The implications of the results for mountain‐wave drag parametrization are discussed. © Crown Copyright 2010. Published by John Wiley & Sons, Ltd.
Shrinking‐horizon dynamic programming
Authors: Skaf Joëlle , Boyd Stephen , Zeevi Assaf 
Published: February 2010

AbstractWe describe a heuristic control policy for a general finite‐horizon stochastic control problem, which can be used when the current process disturbance is not conditionally independent of the previous disturbances, given the current state. At each time step, we approximate the distribution of future disturbances (conditioned on what has been observed) by a product distribution with the same marginals. We then carry out dynamic programming (DP), using this modified future disturbance distribution, to find an optimal policy, and in particular, the optimal current action. We then execute only the optimal current action. At the next step, we update the conditional distribution, and repeat the process, this time with a horizon reduced by one step. (This explains the name ‘shrinking‐horizon dynamic programming’). We explain how the method can be thought of as an extension of model predictive control, and illustrate our method on two variations on a revenue management problem. Copyright © 2010 John Wiley & Sons, Ltd.
River regulation influences the composition and distribution of inland frog communities
Authors: Wassens S. , Maher M. 
Published: February 2010

AbstractFrogs are widespread through inland rivers and floodplains and are an important component of floodplain food chains. Despite this, studies of frog communities in inland river systems are limited and the impacts of river regulation on frog communities have received very little attention. Surveys for frogs, tadpoles and egg masses along with assessment of vegetation, hydrology and water chemistry were conducted along 10 km reaches of three creek systems in the Lachlan River catchment, a major regulated river in Australia's Murray–Darling Basin. A total of 23 sample sites were surveyed at locations above and below in‐stream weirs as well as adjacent floodplain depressions. The hydrological regimes of sample sites were classified according to the length of time that they were known to hold water (water permanence). The sample sites fell into two distinct categories, 14 were classified as permanent and occurred upstream of weirs while nine were classified as temporary and were located downstream of weirs and in depressions adjacent to the weir pool. Permanent sample sites had a significantly higher percentage of dead standing timber and were deeper with less aquatic vegetation cover than temporary sample sites. Seven frog species were identified; there were no significant differences in species richness between permanent and the temporary waterbodies but the composition of frog assemblages differed significantly between them. This suggests that alteration to the hydrology of inland creek systems can lead to changes in the distribution frog species, with some becoming more common due to increases in the availably of permanent waterbodies while others decline due to reductions in the availability of seasonally flooded waterbodies. Copyright © 2010 John Wiley & Sons, Ltd.
The effects of short‐term inundation on carbon dynamics, microbial community structure and microbial activity in floodplain soil
Authors: Wilson J. S. , Baldwin D. S. , Rees G. N. , Wilson B. P. 
Published: February 2010

AbstractA mesocosm study was carried out to determine whether flooding affected soil microbial structure and function. Over a 24 day period soils were either flooded or remained dry and changes in the microbial community structure, microbial metabolic activity (determined by looking at soil respiration rates and exo‐enzyme activity), community level physiological profiles and soil carbon speciation were examined. Flooding induced significant changes in the microbial community structure and increased soil respiration and enzymatic degradation rates. Shifts occurred in carbon speciation after flooding and increases in ‘labile’ carbon fractions were observed. The duration of flooding was also important for carbon dynamics and microbial community structure. Based on the results of the mesocosm experiment a conceptual model of floodplain soils response to flooding over time was formulated. The findings of this mesocosm study illustrate the importance of flooding to floodplain soil functioning. Copyright © 2010 John Wiley & Sons, Ltd.
A high‐resolution hydrodynamic investigation of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss) redds
Authors: Marchildon M. A. , Annable W. K. , Imhof J. G. , Power M. 
Published: February 2010

AbstractHigh‐resolution velocity measurements were taken over a series of redds on a gravel‐bed stream using a Pulse Coherent Acoustic Doppler Profiler (PCADP) to quantify the hydrodynamics of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss) redds. On redds studied, over 4500 velocity measurements per redd were acquired per day to quantify the flow velocity, flow depth and related fluid mechanics metrics of Reynolds numbers, Froude numbers and turbulent kinetic energy per unit area. Results showed that velocity and Froude numbers varied widely at the redd scale, but consistently showed higher velocities and Froude numbers over the tailspill regions relative to the surrounding study limits. Results of Reynolds numbers calculations showed no apparent correlations to spawning location preference and redd structure. Turbulent kinetic energy per unit area consistently demonstrated a strong correlation with redd locations. The metric maintained low values (i.e. unidirectional flow with little turbulence) where all redds and attempted redds were observed. The study also demonstrates that a number of hydraulic metrics and several spatial scales will likely be necessary to understand any inherent relationship between river hydraulics and redd placement. Copyright © 2010 John Wiley & Sons, Ltd.
A boundary corrected expansion of the moments of nearest neighbor distributions
Authors: Liitiäinen Elia , Lendasse Amaury , Corona Francesco 
Published: February 2010

AbstractIn this article, the moments of nearest neighbor distance distributions are examined. While the asymptotic form of such moments is well‐known, the boundary effect has this far resisted a rigorous analysis. Our goal is to develop a new technique that allows a closed‐form high order expansion, where the boundaries are taken into account up to the first order. The resulting theoretical predictions are tested via simulations and found to be much more accurate than the first order approximation obtained by neglecting the boundaries.While our results are of theoretical interest, they definitely also have important applications in statistics and physics. As a concrete example, we mention estimating Rényi entropies of probability distributions. Moreover, the algebraic technique developed may turn out to be useful in other, related problems including estimation of the Shannon differential entropy.© 2010 Wiley Periodicals, Inc. Random Struct. Alg., 2010
Securing business operations in an SOA
Authors: de Leusse Pierre , Brossard David , Georgalas Nektarios 
Published: February 2010

AbstractIn order to achieve agility and shorter concept‐to‐market timescales for new products and services, ICT service providers and their corporate customers alike increasingly adopt a collection of technologies, concepts and capabilities which come under the banner of the Service Oriented Architecture (SOA). The Service Oriented Infrastructure (SOI) approach complements SOA by enabling the optimal use of virtualised infrastructure services and resources via the network, and their integration in tailored solutions that meet customer needs and adapt to their growth pattern.In this paper we focus on the business and technological challenges relating to security and service dependability for SOI. In particular the paper studies challenges in the security areas of (i) identity federation, (ii) distributed usage and access management, (iii) context‐aware secure messaging, routing and transformation and (iv) SOA security governance. It gathers requirements and it proposes an architecture comprising design patterns and a governance framework that address these challenges. An example case‐study presents an implementation of the proposed architecture's SOI security capabilities aiming at the practical validation of the proposed architectural concepts. Copyright © 2010 John Wiley & Sons, Ltd.
Building advanced applications with the Belgian eID
Authors: Lapon Jorn , Naessens Vincent , Verdegem Bram , Verhaeghe Pieter , De Decker Bart 
Published: February 2010

AbstractThe Belgian Electronic Identity Card (eID) was introduced in 2002. The card enables Belgian citizens to digitally prove their identity and to sign electronic documents. Today, only a limited number of citizens really use the card in electronic applications. An important reason is the lack of killer functionality and killer applications.This paper presents two reusable extensions to the Belgian eID technology that opens up new opportunities for application developers. First, a secure and ubiquitously accessible remote storage service is presented. Second, it is shown how the eID card can be used to issue new certificates. The feasibility and reusability of both extensions are validated through the development of several applications in different domains. Copyright © 2010 John Wiley & Sons, Ltd.
Defending Sybil attacks based on neighboring relations in wireless sensor networks
Authors: Wang Wei‐Tong , Ssu Kuo‐Feng , Chang Wen‐Chung 
Published: February 2010

AbstractAs the prevalence of Wireless Sensor Networks (WSNs) grows in the military and civil domains, network security becomes an evermore critical concern. In Sybil attack, malicious nodes forge a lot of fake identities to disrupt the network's protocols. Previous work used either authentication‐based mechanisms which use shared encryption keys, or location information to verify the identities of the nodes. By contrast, this paper uses only neighboring node relation to verify the node identities. The evaluation results show that the detection rate was around 95% when the network was not very sparse. Copyright © 2010 John Wiley & Sons, Ltd.
Negative workplace behaviour: temporal associations with cardiovascular outcomes and psychological health problems in Australian police
Authors: Tuckey Michelle R. , Dollard Maureen F. , Saebel Judith , Berry Narelle M. 
Published: February 2010

AbstractNegative workplace behaviour, such as workplace bullying, is emerging as an important work‐related psychosocial hazard with the potential to contribute to employee ill health. We examined the risk of two major health issues (poor mental and cardiovascular health) associated with current and past exposure to negative behaviour in the workplace. Data from 251 police officers, who completed an anonymous mail survey at two time‐points spaced 12 months apart, support the potential role of exposure to negative workplace behaviour in the development of physical disease and psychological illness. Specifically, we saw significant effects associated with past exposure to such behaviour on indicators of poor cardiovascular health, and a significant effect of current exposure on the indicator of mental health problems. Our findings reinforce the need to continue to study links between employee health and both negative workplace behaviour and more severe cases of bullying, particularly the mechanisms involved to strengthen theory in this area, and to protect against employee ill health (specifically cardiovascular outcomes and psychological problems) by preventing negative behaviour at work. Copyright © 2010 John Wiley & Sons, Ltd.
Conjugated‐Polyelectrolyte‐Functionalized Reduced Graphene Oxide with Excellent Solubility and Stability in Polar Solvents
Authors: Qi Xiaoying , Pu Kan‐Yi , Zhou Xiaozhu , Li Hai , Liu Bin , Boey Freddy , Huang Wei , Zhang Hua 
Published: February 2010

AbstractConjugated‐polyelectrolyte (CPE)‐functionalized reduced graphene oxide (rGO) sheets are synthesized for the first time by taking advantage of a specially designed CPE, PFVSO3, with a planar backbone and charged sulfonate and oligo(ethylene glycol) side chains to assist the hydrazine‐mediated reduction of graphene oxide (GO) in aqueous solution. The resulting CPE‐functionalized rGO (PFVSO3‐rGO) shows excellent solubility and stability in a variety of polar solvents, including water, ethanol, methanol, dimethyl sulfoxide, and dimethyl formamide. The morphology of PFVSO3‐rGO is studied by atomic force microscopy, X‐ray diffraction, and transmission electron microscopy, which reveal a sandwich‐like nanostructure. Within this nanostructure, the backbones of PFVSO3 stack onto the basal plane of rGO sheets via strong π–π interactions, while the charged hydrophilic side chains of PFVSO3 prevent the rGO sheets from aggregating via electrostatic and steric repulsions, thus leading to the solubility and stability of PFVSO3‐rGO in polar solvents. Optoelectronic studies show that the presence of PFVSO3 within rGO induces photoinduced charge transfer and p‐doping of rGO. As a result, the electrical conductivity of PFVSO3‐rGO is not only much better than that of GO, but also than that of the unmodified rGO.
Software project effort assessment
Authors: Haapio Topi , Eerola Anne 
Published: February 2010

AbstractSoftware project assessments and postmortem analyses can increase the success of future projects and forthcoming project phases. However, although assessments and analyses are well‐presented in the software engineering literature, they are short of descriptions to assess effort. This paper proposes a stepwise effort assessment method that strives to facilitate learning from past experiences and to increase effort estimation accuracy by exploring realized project effort. The proposed method can be used either to assess the realized project effort of a time span from project's lifecycle or as a part of the whole project postmortem analysis in producing effort information for the project iteration assessment, final report, and annual project portfolio report. In addition, the effort information increases the project team's knowledge on realized activity sets and their relationships, and the information can be utilized in estimation method and model calibration for both re‐estimations and future estimations. The method was evaluated with case projects, a sample supplied by Tieto Finland Oy. Copyright© 2010 John Wiley & Sons, Ltd.
Functional Properties and Retrogradation of Heat‐Moisture Treated Wheat and Potato Starches in the Presence of Hydroxypropyl β‐cyclodextrin
Authors: Gunaratne Anil , Kong Xiangli , Corke Harold 
Published: February 2010

AbstractSome functional and retrogradation properties of native and heat‐moisture treated potato and wheat starches were examined in the presence of hydroxypropyl β‐cyclodextrin (HPβ‐CD). HPβ‐CD increased swelling factor, amylose leaching, and solubility of both native and heat‐moisture treated wheat starches but it had less impact on corresponding potato starches. Gelatinization enthalpy of native wheat starch was decreased in the presence of HPβ‐CD but was increased in potato starch with increasing concentration. Reduction of amylose‐lipid complex endotherm in both native and heat‐moisture treated wheat starch was observed in the presence of HPβ‐CD. Heat‐moisture treatment did not change the transition parameters of amylose‐lipid complex showing its resistance to hydrothermal treatment. HPβ‐CD greatly decreased the pasting temperature of wheat starch. Cold paste viscosity of both native and heat‐moisture treated wheat starch was increased by HPβ‐CD to a greater extent than corresponding potato starch. Amylopectin retrogradation of all the starches was unaffected in the presence of HPβ‐CD but heat‐moisture treatment slightly decreased retrogradation of potato starch. These results suggest that HPβ‐CD can disrupt the amylose‐lipid complex within the starch granule in both native and heat‐moisture treated wheat starch but has no influence on amylopectin retrogradation. However, greatly increased wheat starch setback with HPβ‐CD indicates its greater effect on wheat starch amylose retrogradation.
Ductus venosus blood flow velocity waveform in diabetic pregnancies
Authors: Stuart A. , Amer‐Wåhlin I. , Gudmundsson S. , Maršál K. , Thuring A. , Källen K. 
Published: February 2010

AbstractObjectiveMaternal diabetes during pregnancy is associated with congenital cardiac malformations and hypertrophic cardiomyopathy. Blood flow in the ductus venosus (DV) has been postulated to reflect cardiac function. The aim of our study was to investigate if diabetic pregnancies exhibit abnormal DV hemodynamics, hence indicating changes in fetal cardiac function.MethodsThe pulsatility index of the DV (DV‐PI) was analyzed retrospectively in 142 diabetic patients and compared to previously published DV‐PI reference values from a non‐diabetic low‐risk population. DV values were then correlated with maternal glycosylated hemoglobin (HbA1c).ResultsDV‐PI was significantly higher in pregnancies complicated by either pre‐existing insulin‐dependent (DM) or gestational diabetes when compared with normal reference values. Increased DV‐PI values were still evident in both diabetic groups when neonates that were small‐for‐gestational age and neonates with pathological umbilical blood flow pattern were excluded from the analysis. In DM pregnancies a statistically significant correlation was found between DV‐PI and maternal HbA1c.ConclusionDiabetic pregnancies exhibit increased DV‐PI values when compared to a normal low‐risk pregnant population, possibly indicating a fetal cardiac effect. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Learning curve in measurement of fetal frontomaxillary facial angle at 11–13 weeks of gestation
Authors: Yang X. , Chen M. , Wang H. F. , Leung T. Y. , Borenstein M. , Nicolaides K. , Sahota D. S. , Lau T. K. 
Published: February 2010

AbstractObjectiveTo determine the number of ultrasound examinations required to train sonographers to accurately measure the fetal frontomaxillary facial (FMF) angle at 11–13 weeks of gestation.MethodsEight sonographers accredited for nuchal translucency thickness (NT) measurement (and with different levels of experience) were trained to measure the fetal FMF angle using specially acquired three‐dimensional (3D) volumes. Training was provided in cycles, and each cycle consisted of a training period on 20 randomly selected cases followed by an examination using 10 randomly selected cases. During training, the sonographer was informed of the true FMF angle value after each FMF angle measurement on a case‐by‐case basis. During examination, the difference between the measured and the true values of the FMF angle (i.e. the delta angle) was calculated. A measurement was considered accurate if the delta angle was less than 5°. The sonographer was considered to be competent and the training finished if all 10 examination cases satisfied this criterion. Otherwise, the sonographer would undergo further cycles of training–examination, until he/she became competent.ResultsThe number of training cases required for a sonographer to become competent was 40 for two sonographers, 60 for one, 80 for one, 100 for two, 120 for one and 140 for one, with a median of 90. The median number of failed cases reduced from 2.5 (out of 10) at the first cycle to 0 by the 7th cycle. As training cycles increased, the mean angle deviation and measurement time required both reduced significantly. The average delta angle of the passing examination cycle was 2.06 ± 1.40°. The number of training cases required to become competent in FMF angle measurement was 40 for the two most experienced trainees and 80, 120 and 140 for the three least experienced ones.ConclusionsWe have demonstrated that competence in FMF angle measurement was achieved after a median number of 90 cases, with a range of up to 140. The number required was substantially lower, at 40 cases, among those with extensive experience of NT measurement. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
A practical authentication protocol with anonymity for wireless access networks
Authors: Chen Yen‐Cheng , Chuang Shu‐Chuan , Yeh Lo‐Yao , Huang Jiun‐Long 
Published: February 2010

AbstractThe use of anonymous channel tickets was proposed for authentication in wireless environments to provide user anonymity and to probably reduce the overhead of re‐authentications. Recently, Yanget al.proposed a secure and efficient authentication protocol for anonymous channel in wireless systems without employing asymmetric cryptosystems. In this paper, we will show that Yanget al.'s scheme is vulnerable to guessing attacks performed by malicious visited networks, which can easily obtain the secret keys of the users. We propose a new practical authentication scheme not only reserving the merits of Yanget al.'s scheme, but also extending some additional merits including: no verification table in the home network, free of time synchronization between mobile stations and visited networks, and without obsolete anonymous tickets left in visited networks. The proposed scheme is developed based on a secure one‐way hash function and simple operations, a feature which is extremely fit for mobile devices. We provide the soundness of the authentication protocol by using VO logic. Copyright © 2010 John Wiley & Sons, Ltd.