bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adaptive fixed‐time fault‐tolerant control for rigid spacecraft using a double power reaching law
Authors: Tao Meiling , Chen Qiang , He Xiongxiong , Sun Mingxuan 
Published: June 2019

SummaryIn this paper, an adaptive fixed‐time fault‐tolerant control scheme is presented for rigid spacecraft with inertia uncertainties and external disturbances. By using an inverse trigonometric function, a novel double power reaching law is constructed to speed up the state stabilization and reduce the chattering phenomenon simultaneously. Then, an adaptive fixed‐time fault‐tolerant controller is developed for the spacecraft with the actuator faults, such that the fixed‐time convergence of the attitude and angular velocity could be guaranteed, and no prior knowledge on the upper bound of the lumped uncertainties is required anymore in the controller design. Comparative simulations are provided to illustrate the effectiveness and superior performance of the proposed scheme.
Human influence on the morphological adjustment of river channels: The evolution of pertinent concepts in river science
Authors: Gregory Kenneth J. 
Published: June 2019

AbstractWhereas 6 decades ago little attention was accorded to the influence of human activity on affecting river channel adjustment, great progress has been made subsequently, with many contributions published in River Research and Applications. Many concepts have been involved, and this paper considers how they have arisen and developed during a sequence of complementary research stages. The first stage during the 1970s and 1980s, including research by Geoff Petts, involved “recognition of change” and saw the emergence of two separate research strands focused on different timescales: over shorter timescales river channel adjustments affected by the impacts of dams and reservoirs, channelization, land use changes, and urban effects; over longer timescales investigations of river metamorphosis. The second “realization” stage involved significant advances in understanding by considering interaction between these two timescales, more detailed investigations of changing processes, a more holistic catchment‐based approach, and incorporation of ecological changes. These advances led into the third stage, “application” of results, stimulated by analysis of the effects of hard and soft engineering, development of international drivers such as the Water Framework Directive, and concern for what is “natural.” This paper evaluates this sequence of stages, the concepts that have emerged, the extent to which they are consistent and sustainable, and how they can provide the foundation for evaluation of channel adjustments. The effects of urbanization in Fountain Hills, Arizona, USA provide an illustration. Finally, the future requirement for adaptation of existing concepts and the possible development of new ones is briefly considered in the context of global environmental changes.
Framework for cloud‐based software test data generation service
Authors: Chawla Priyanka , Chana Inderveer , Rana Ajay 
Published: June 2019

SummaryThis paper presents the framework of cloud‐based software test data generation service (CSTS) that caters to cost‐effective test data generation service in a cloud environment. In contrast to existing conventional or cloud‐based testing frameworks, CSTS has a number of unique benefits. First, CSTS is designed to facilitate test data generation in minimum time and cost. Second, unlike existing frameworks which mandates clients to opt for resources to test their jobs, CSTS guides customer for selecting best cluster configuration in order to minimize the cost. While the existing models do not provide any solution for trust establishment in cloud computing services, CSTS delivers it by implementing security mechanism with the provision of role based access control. The security mechanism proposed in this paper ensures the protection of data and code of different users. Third, CSTS provides a mathematical pricing model to fulfill the expectations of customers and also to maximize the net profit of service providers. Cloud service request model has also been designed that postulates service level agreements between customers and service providers. We have evaluated, compared, and analyzed our framework and have found that it outperforms other existing cloud‐based frameworks.
Nanoparticles used for fingermark detection—A comprehensive review
Authors: Kanodarwala Fehmida K. , Moret Sébastien , Spindler Xanthe , Lennard Chris , Roux Claude 
Published: June 2019

AbstractNanoparticles (NPs) have been used in numerous fields such as medicine, imaging, and electronics to cite just a few. In forensic science, NPs have been researched specifically for the detection of fingermarks. Their small size, surface functionalization ability, and luminescence properties can potentially lead to better resolution, increased sensitivity, and selectivity. This paper offers an extensive review of the various NP types investigated over the past three decades. NPs are sorted into seven categories, namely metal, metal oxide, quantum dots (QDs), carbon dots (C‐dots), silica (SiO2), and upconverters NPs (UCNPs) as well as a miscellaneous section. Each type is discussed in details from a critical viewpoint. The most promising NP types are also identified.This article is categorized under:Forensic Chemistry and Trace Evidence > Fingermarks and Other Marks
Does informant‐based reporting of cognitive symptoms predict amyloid positivity on positron emission tomography?
Authors: Brunet Hannah E. , Miller Justin B. , Shi Jiong , Chung Briana , Munter Bryce Taylor , Sabbagh Marwan Noel 
Published: June 2019

AbstractIntroductionResearchers are searching for clinical instruments to predict amyloid positivity for disease classification. Informant‐based reports could detect disease status. This study compares subjective memory complaints captured by informant‐based reports between positron emission tomography (PET)–positive and PET‐negative patients and hypothesizes that amyloid PET positivity associates with increased informant‐based cognitive complaints.MethodsNinety‐eight amnestic mild cognitive impairment or mild dementia subjects were studied. Subjective report was captured by the informant‐driven Alzheimer's Questionnaire (AQ) administered before PET. Differences in demographics and AQ score by diagnostic status and amyloid status were measured, and a receiver‐operating characteristic curve was calculated.ResultsSixty‐five mild cognitive impairment/Alzheimer's disease amyloid PET‐positive and 33 amyloid PET‐negative subjects were included. AQ was significantly higher (12.51 ± 4.95) for amyloid PET‐positive subjects (9.06 ± 3.65; P = .001).ConclusionsAmyloid PET‐positive subjects with Alzheimer's disease or mild cognitive impairment have more informant‐based reports of cognitive decline, indicating utility for a brief informant measure.
Analysis of dementia in the US population using Medicare claims: Insights from linked survey and administrative claims data
Authors: Chen Yi , Tysinger Bryan , Crimmins Eileen , Zissimopoulos Julie M. 
Published: June 2019

AbstractIntroductionMedicare claims data may be a rich data source for tracking population dementia rates. Insufficient understanding of completeness of diagnosis, and for whom, limits their use.MethodsWe analyzed agreement in prevalent and incident dementia based on cognitive assessment from the Health and Retirement Study for persons with linked Medicare claims from 2000 to 2008 (N = 10,450 persons). Multinomial logistic regression identified sociodemographic factors associated with disagreement.ResultsSurvey‐based cognitive tests and claims‐based dementia diagnosis yielded equal prevalence estimates, yet only half were identified by both measures. Race and education were associated with disagreement. Eighty‐five percent of respondents with incident dementia measured by cognitive decline received a diagnosis or died within the study period, with lower odds among blacks and Hispanics than among whites.DiscussionsClaims data are valuable for tracking dementia in the US population and improve over time. Delayed diagnosis may underestimate rates within black and Hispanic populations.
On the detection of internal interfacial layers in turbulent flows
Authors: Fan Duosi , Xu Jinglei , Yao Matthew X. , Hickey Jean-Pierre 
Published: June 2019

A novel approach to identify internal interfacial layers, or IILs, in wall-bounded turbulent flows is proposed. Using a fuzzy cluster method (FCM) on the streamwise velocity component, a unique and unambiguous grouping of the uniform momentum zones (UMZs) is achieved, thus allowing the identification of the IILs. The approach overcomes some of the key limitations of the histogram-based IIL identification methods. The method is insensitive to the streamwise domain length, can be used on inhomogeneous grids, uses all the available flow field data, is trivially extended to three dimensions and does not need user-defined parameters (e.g. number of bins) other than the number of zones. The number of zones for a given snapshot can be automatically determined by an a priori algorithm based on a kernel density estimation algorithm, or KDE. This automated approach is applied to compute the average number of UMZs as a function of Reynolds number $Re_{\unicode[STIX]{x1D70F}}$ in turbulent channel flows in several numerical simulations. This systematic approach reveals a dependence of the Reynolds number on the average number of UMZs in the channel flow; this supports previously reported observations in the boundary layer. The fuzzy clustering approach is applied to the turbulent boundary layer (experimental, planar particle image velocimetry) and channel flow (numerical, direct numerical simulation) at varying Reynolds numbers. The interfacial layers are characterized by a strong concentration of spanwise vorticity, with the outer-most layer located at the upper edge of the log layer. The three-dimensional interface identification reveals a streak-like organization. The large-scale motion (LSM) at the outer region of the channel flow boundary layer modulates the outer IIL. The corrugations of the outer IIL are aligned with the LSM and the conditional correlation of the inner and outer IIL height shows that extreme near-wall events leave their mark on the outer IIL corrugations.
Universal scaling law for drag-to-thrust wake transition in flapping foils
Authors: Lagopoulos N. S. , Weymouth G. D. , Ganapathisubramani B. 
Published: June 2019

Reversed von Kármán streets are responsible for a velocity surplus in the wake of flapping foils, indicating the onset of thrust generation. However, the wake pattern cannot be predicted based solely on the flapping peak-to-peak amplitude $A$ and frequency $f$ because the transition also depends sensitively on other details of the kinematics. In this work we replace $A$ with the cycle-averaged swept trajectory ${\mathcal{T}}$ of the foil chordline. Two-dimensional simulations are performed for pure heave, pure pitch and a variety of heave-to-pitch coupling. In a phase space of dimensionless ${\mathcal{T}}-f$ we show that the drag-to-thrust wake transition of all tested modes occurs for a modified Strouhal $St_{{\mathcal{T}}}\rightarrow 1$. Physically, the product ${\mathcal{T}}f$ expresses the induced velocity of the foil and indicates that propulsive jets occur when this velocity exceeds $U_{\infty }$. The new metric offers a unique insight into the thrust-producing strategies of biological swimmers and flyers alike, as it directly connects the wake development to the chosen kinematics, enabling a self-similar characterisation of flapping foil propulsion.
Amino acid content of selected plant, algae and insect species: a search for alternative protein sources for use in pet foods
Authors: McCusker Sarah , Buff Preston R. , Yu Zengshou , Fascetti Andrea J. 
Published: June 2019

AbstractIn response to global economic duress and heightened consumer awareness of nutrition and health, sustainable and natural ingredients are in demand. Identification of alternative sources of nitrogen and amino acids, including taurine, may help meet dietary requirements while fostering sustainability and natural feeding approaches. Twenty plants, eighteen marine algae and five insect species were analysed. All samples were freeze-dried, hydrolysed and filtered prior to amino acid analysis. Samples for amino acids were analysed in duplicate and averaged. Nitrogen was analysed and crude protein (CP) determined by calculation. With the exception of taurine concentration in soldier fly larvae, all insects exceeded both the National Research Council's canine and feline minimal requirements (MR) for growth of all essential amino acids (EAA) and CP. Although some plants and marine algal species exceeded the canine and feline MR for growth for EAA and CP, only very low concentrations of taurine were found in plants. Taurine concentration in insects was variable but high, with the greatest concentration found in ants (6·42 mg/g DM) and adult flesh flies (3·33 mg/g DM). Taurine was also high in some macroalgae, especially the red algal species: Mazaella spp. (4·11 mg/g DM), Porphyra spp. (1·22 mg/g DM) and Chondracanthus spp. (6·28 mg/g DM). Preliminary results suggest that insects and some marine algal species may be practical alternatives to traditional protein and supplemental taurine sources in pet foods. Safety, bioavailability, palatability and source variability of alternative items as food ingredients should be investigated prior to incorporation into canine and feline diets.
Buckling of Oblique Plates with Clamped Edges Under Uniform Shear
Authors: Wittrick W. H. 
Published: June 2019

SummaryIn a previous paper the author derived, by the Rayleigh-Ritz method, a determinantal equation for obtaining the critical magnitude of any uniform system of edge stress applied to a clamped oblique plate. In the present paper this equation is used to derive values for the buckling stresses of clamped oblique plates subjected to pure shear along and perpendicular to two edges of the plate.As would be expected, it is found that reversal of the direction of the shear produces a change in the critical value. The lower value occurs when the shear is tending to increase the obliquity of the plate and critical values corresponding to this direction are calculated for 45° oblique plates with side ratios varying between 3/5 and 5/3. The critical values obtained for the reverse direction were obviously very inaccurate, due to the inadequacy of the series which was used to represent the buckling mode. As yet no satisfactory method has been found for overcoming this difficulty.
Mixing and the Jet Flap
Authors: Stratford B. S. 
Published: June 2019

SummaryOne of the main problems associated with the “ Jet Flap ” concerns the discrepancy in thrust between idealised theory and the experimental results. This discrepancy is attributable to the mixing with the surrounding flow of the thin two-dimensional jet while still in close proximity to the aerofoil. The effect of the mixing may be calculated to a first approximation from a formula derivable from first principles, while certain second order effects, which can be significant, may be considered qualitatively.It is concluded that.(i) the full thrust should be experienced by a jet flapped aircraft at cruise,(ii) it should be possible to attain a low form drag at cruise in comparison with a conventional aircraft,(iii) at take-off, an aircraft using a shrouded jet flap would have better thrust recovery than one using a pure jet flap (which shows appreciable losses),(iv) the use of by-pass engines would further improve the thrust characteristics,(v) the practical gains from thrust augmentation, as obtained by controlling the mixing, seem likely to be small.
The Behaviour of Damped Linear Systems in Steady Oscillation
Authors: Bishop R. E. D. 
Published: June 2019

In this paper (published in The Aeronautical Quarterly, Vol. VII, Part 2, p. 156, May 1956), a set of equations is derived giving the responses at the generalised coordinates q1, q2, … qn which are caused by a harmonic generalised force Φseiωt corresponding to qs. They are equations (26), namelyThis note is concerned with a sentence which follows these equations which says (of them) that “ … there is no longer any assurance that the ratios between the constants mBrs in any column of partial fractions are the same for all co-ordinates qs at which excitation is applied, since the previous limiting condition cannot now be applied. Thus the shapes of the ‘ modes ’ which are associated with the various columns depend upon the nature of the applied harmonic excitation.”
Pre-operative prediction of cholesteatomas from radiology: retrospective cohort study of 106 cases
Authors: Selwyn D , Howard J , Cuddihy P 
Published: June 2019

AbstractObjectivePre-operative imaging is often used to predict the extent of a cholesteatoma and anatomical variation to plan for surgery. This study aimed to measure the predictive accuracy of computed tomography findings.MethodsA retrospective cohort study was conducted of all patients in a district general hospital undergoing mastoid surgery within a consecutive 12-month period, in whom computed tomography had been performed prior to operative intervention. The study measured the key findings of pre-operative computed tomography imaging and compared them to the intra-operative findings.ResultsA total of 106 patients were included. The sensitivity and specificity for predicting cholesteatoma were 79 per cent and 81 per cent respectively. The positive predictive value was 90 per cent and the negative predictive value was 65 per cent. In predicting complications of cholesteatomas, the sensitivity was 70 per cent, whereas the specificity was 91 per cent. The positive predictive value was 88 per cent and the negative predictive value was 76 per cent.ConclusionPre-operative computed tomography conducted prior to mastoid surgery has high positive predictive values for both predicting cholesteatomas and complications (90 per cent and 88 per cent respectively).
Strain variation inEntamoeba histolytica
Authors: Neal R. A. 
Published: June 2019

1. The total bacterial floras from invasive strains ofEntamoeba histolytica, when added to non-invasive strains, do not increase the invasiveness of the latter.2. The bacterial flora of non-invasive strains do not inhibit the invasiveness of virulent strains.3. Bacteria from a virulent substrain (revived by serial liver passage) do not increase the invasiveness of the attenuated parent strain.4. It is concluded that the virulence of a strain ofE. histolyticais primarily dependent upon the invasiveness of the amoeba itself.
The amber beads
Authors: Sandars Nancy 
Published: June 2019

It has long been axiomatic that amber is seldom found in Crete, and it is therefore of some interest to be able to record amber beads in two of the Gypsades tombs, Nos. II and VII. In Mycenaean sites on the mainland of Greece amber beads of different shapes are found in great numbers and so frequently as to appear a fairly constant feature of these sites; certainly as much as faience and rather more so than lapis lazuli, an exotic from Asia.In the shaft-graves of both the new and old grave circles at Mycenae amber is plentiful and thereafter at Prosymna in graves dating from Late Helladic I to Late Helladic III; and this is characteristic of all the principal sites, though the number of beads found may be much smaller. Amber is also particularly plentiful on the west coast of the Peloponnese: at Kakovatos in Elis, in tholos A (dated L.H. IIA); at Epano Englianos in western Messenia, in the tholos excavated by Lord William Taylour, close to the palace, and dated to the fifteenth century or earlier, in which about 360 beads were recovered; and in the second tholos recently excavated by Professor Marinatos at Myrsinochorion in the same area. Farther north there was much in the Ionian Islands, particularly in Cephalonia; and a little has been found in Epirus.
Nemesis: A Mycenaean settlement near the Menidi Tholos Tomb
Authors: Simpson R. Hope 
Published: June 2019

The site to be described lies on a low hill a little to the north of the small village or suburb of Nemesis, about 150 metres to the west of the main road from Patisia to Koukouvaounes, and 1 kilometre to east-south-east of the Mycenaean tholos tomb at Λυκὸτρυπα, which was excavated by the German Institute in 1879, and is usually called the Menidi Tomb. The site at Nemesis is visible from the tholos tomb, and is separated from it by a gentle valley through which run, in a southerly direction, two streams with steep banks. The eastern stream is the river Kephissos, whose name goes back at least as far as the classical period.The hill of Nemesis stands about 15 to 20 metres above the level of the surrounding land, and measures about 160 m. north-west to south-east × 120 m. north-east to south-west. The hill is an isolated outcrop of conglomerate rock, thinly covered with stony brown earth. It has been eroded over an area about 250 m. north-south × 50 m. east-west, so that its original size was considerably larger than at present, in all about 30,000 square metres. Mycenaean sherds were found over the whole of this area, though mainly in the eroded part, among the lumps of fallen earth and rock. Remains of rubble walling together with several Mycenaean sherds were found here, and also in the steep cliffs formed by the erosion on the west and south sides (this part of the hill has been undermined by recent excavation of the beds of grey clay, which here lie at between 2 and 3 metres below the original ground level). The ancient remains are particularly noticeable in the south-west angle of the cliffs (roughly in the centre of the part of the hill shown on Plate 71a), where there is a greater depth of earth above the rock than is visible elsewhere on the hill.
Canada’s Reluctant Participation in the International Commission for Control and Supervision in Vietnam in 1973
Authors: Dai Poeliu 
Published: June 2019

Canada’s brief participation in the International Commission for Control and Supervision (ICCS) in Vietnam, from the end of January to July 31, 1973, ended her active role as a supervisory power for maintaining peace in Indo-China, although it did not imply an abandonment of her traditional policy of working in the interests of international stability and coexistence.Canada was a natural choice for the new peace-keeping machinery by virtue of her 19-year experience in the three International Control Commissions (ICC), even though she had taken no part in the protracted secret negotiations that led to the Agreement on Ending the War and Restoring Peace in Vietnam signed on January 27, 1973, by the United States, the Democratie Republic of Vietnam, the Republic of Vietnam, and the Provisional Revolutionary Government of the Republic of South Vietnam. The American Secretary of State, Mr. William P. Rogers, and the Canadian Minister for External Affairs, Mr. Mitchell Sharp, therefore consulted as early as October 25 and subsequently on November 20, 1972, to consider Canada’s possible participation, with Indonesia, Hungary, and Poland, in a new agency to be known as ICCS.