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This paper studies the constrained two-dimensional guillotine cutting problem with defects, whose objective is to cut a subset of given items from a defective sheet such that the profit of selected items is maximised. The guillotine cut constraint, which requires each cut must go through one side of the sheet to the opposite side, is considered. We solve this problem via a recursive dynamic programming approach. A set of upper bounds is proposed to keep the promising nodes. The normal points and raster points are extended to reduce the number of vertical and horizontal cuts by considering the effect of the defect. The experiment results show that our approach can solve most of the instances in the literature and outperforms existing approaches. [ABSTRACT FROM AUTHOR]

A major open problem of AF-embedding is whether every separable exact quasidiagonal C ∗ -algebra can be embedded into an AF-algebra. In this paper we characterize AF-embeddable C ∗ -algebras by representations to observe their similarity to the separable exact quasidiagonal C ∗ -algebras. As an application, we show that every separable exact quasidiagonal C ∗ -algebra is AF-embeddable if and only if every faithful essential representation of a separable exact quasidiagonal C ∗ -algebra is a certain kind of ∗ -representation. We also show that a separable C ∗ -algebra is AF-embeddable if and only if it can be embedded into a particular C ∗ -algebra. [ABSTRACT FROM AUTHOR]

RationaleIt has been suggested that patients with chronic obstructive pulmonary disease (COPD) experience considerable daily respiratory symptom fluctuation. A standardized measure is needed to quantify and understand the implications of day-to-day symptom variability.ObjectivesTo compare standard deviation with other statistical measures of symptom variability and identify characteristics of individuals with higher symptom variability.MethodsIndividuals in the SubPopulations and InteRmediate Outcome Measures In COPD Study (SPIROMICS) Exacerbations sub-study completed an Evaluating Respiratory Symptoms in COPD (E-RS) daily questionnaire. We calculated within-subject standard deviation (WS-SD) for each patient at week 0 and correlated this with measurements obtained 4 weeks later using Pearson's r and Bland Altman plots. Median WS-SD value dichotomized participants into higher versus lower variability groups. Association between WS-SD and exacerbation risk during 4 follow-up weeks was explored.Measurements and main resultsDiary completion rates were sufficient in 140 (68%) of 205 sub-study participants. Reproducibility (r) of the WS-SD metric from baseline to week 4 was 0.32. Higher variability participants had higher St George's Respiratory Questionnaire (SGRQ) scores (47.3 ± 20.3 versus 39.6 ± 21.5, p=.04) than lower variability participants. Exploratory analyses found no relationship between symptom variability and health care resource utilization-defined exacerbations.ConclusionsWS-SD of the E-RS can be used as a measure of symptom variability in studies of patients with COPD. Patients with higher variability have worse health-related quality of life. WS-SD should be further validated as a measure to understand the implications of symptom variability.

In this study, we investigate the behavior of inertial active Brownian particles in a d -dimensional harmonic trap in the presence of translational diffusion. While the solution of the Fokker–Planck equation is generally challenging, it can be utilized to compute the exact time evolution of all time-dependent dynamical moments using a Laplace transform approach. We present the explicit form for several moments of position and velocity in d -dimensions. An interplay of time scales assures that the effective diffusivity and steady-state kinetic temperature depend on both inertia and trap strength, unlike passive systems. The distance from equilibrium, measured by the violation of equilibrium fluctuation-dissipation and the amount of entropy production, decreases with increasing inertia and trap strength. We present detailed ‘phase diagrams’ using kurtosis of velocity and position, showing possibilities of re-entrance to equilibrium.

Radiotherapy is a recommended procedure, in average, for 52% of cancer cases as one of the treatment forms, therefore, it is important for the clinical practice to investigate the affecting factors in dose distribution received by the patients, and for example, devices and treatment couch. With the introduction of treatments with modulated intensity techniques like IMRT and VMAT, the number of incidence fields used for patient treatment increased, which makes the couch’s dosimetric effect more significant in these modalities. The attenuation data acquisition referring to the treatment couches, as well as the TPS data evaluation, show as important parameters for the clinical practice because they show what happens with the dose delivery during the treatment, ensuring a better quality and safety to the treatments. This research presents experimental results evaluating the couch’s impact in the treatments by a study of perturbation in the distribution of surface dose, dose attenuation according to the gantry’s angle for the couches BrainLABTM, ExactTM and iBEAMTM. Then we propose better density values for the couches BrainLABTM and ExactTM for their inclusion in EclipseTM TPS. Lastly, we compare the dose difference considering the presence or not of couch in the planning. In conclusion, the beam’s attenuation increase by the couches and the doses alterations on the skin must be taken in consideration in the treatment planning process. It is of great relevance that each treatment center perform internal tests to determinate the best density values for available TPS.

We expand upon work from many hands on the decomposition of nuclear maps. Such maps can be characterised by their ability to be approximately written as the composition of maps to and from matrices. Under certain conditions (such as quasidiagonality), we can find a decomposition whose maps behave nicely, by preserving multiplication up to an arbitrary degree of accuracy and being constructed from order-zero maps (as in the definition of nuclear dimension). We investigate these conditions and relate them to a W*-analogue. [ABSTRACT FROM AUTHOR]

Let X be a continuum and let n be a positive integer. We consider the hyperspaces Fn(X) and SFn(X). If m is an integer such that n > m ≥ 1, we consider the quotient space SFnm(X). For a given map f : X → X, we consider the induced maps Fn(f) : Fn(X) → Fn(X), SFn(f) : SFn(X) → SFn(X) and SFnm(f) : SFnm(X) → SFnm(X). In this paper, we introduce the dynamical system (SFnm(X), SFnm (f)) and we investigate some relationships between the dynamical systems (X, f), (Fn(X), Fn(f)), (SFn(X), SFn(f)) and (SFnm(X), SFnm(f)) when these systems are: exact, mixing, weakly mixing, transitive, totally transitive, strongly transitive, chaotic, irreducible, feebly open and turbulent.

Man asks himself; who am I? Man thinks for his true identity. He wants to know his source and destination. Thus he wants to know his past and future existence. The baby was not into existence yesterday. Today it comes into existence. The process of birth astonishes him. He hears the throb of life. Very soon it will inherit an identity from its parents. Philosophical emotion isolates a person from mundane existence. [ABSTRACT FROM AUTHOR]

In this study, we compare 10 (ten) optimization methods both exact algorithm (B&B) and approximate algorithm: GA, SA, TS, ACO, PSO, ABC, A³, NN, 2-Opt for symmetric traveling salesman problem. By using software Lingo18 and Matlab R18a, these algorithms are tested in five cases: 30 cities of Sumatera, 70 cities of Java, 9 cities of Kalimantan, 11 cities of Sulawesi, and 29 cities in Papua. Exact method (B&B) yields the shortest distance and time for less than 30 cities, on the other hand, metaheuristics (ABC) yields better than other metaheuristics algorithms both time and distance for more than 30 cities. To test the effectivity of ABC algorithm, this algorithm is also tested in tsplib and has error rate in Danzig42 (0.00%), Brazil58 (0.02%), Gr120 (10.13%). [ABSTRACT FROM AUTHOR]

The goal of the present paper is to disclose three different ways to determine the heat transfer rate in annular fins of rectangular profile employing the fin efficiency concept. The first way is evaluating the exact, analytical equation accounting for four modified Bessel functions I 0(X), I 1(X), K 0(X), K 1(X), the second way is employing the fin efficiency diagram designed by Gardner and the third way is evaluating the one-term empirical correlation equation developed by Schmidt. [ABSTRACT FROM AUTHOR]

In this technical note, the problem concerning the quantification of heat transfer rates from an array of longitudinal radiating fins of rectangular profile in a tube/fin ensemble to a nonzero temperature sink is investigated. Radiating fins constitute essential elements in the thermal control of spacecrafts and satellites. We consider quasi one‐dimensional heat conduction in the longitudinal radiating fins and neglect radiative exchange between the fins and the tubes carrying a hot fluid. It is demonstrated that the governing nonlinear differential equation of second order with constant coefficients and nonhomogeneous can be solved in exact, analytical implicit form. The pertinent temperature distributions eventually provide the magnitudes of heat transfer rates and fin efficiencies influenced by the radiation–conduction parameter and the sink temperature. [ABSTRACT FROM AUTHOR]

This study aimed to illustrate how a new methodology to assess clinical trial outcome measures using a longitudinal item response theory–based model (IRM) could serve as an alternative to mixed model repeated measures (MMRM). Data from the EXACT (Exacerbation of chronic pulmonary disease tool) which is used to capture frequency, severity, and duration of exacerbations in COPD were analyzed using an IRM. The IRM included a graded response model characterizing item parameters and functions describing symptom-time course. Total scores were simulated (month 12) using uncertainty in parameter estimates. The 50th (2.5th, 97.5th) percentiles of the resulting simulated differences in average total score (drug minus placebo) represented the estimated drug effect (95%CI), which was compared with published MMRM results. Furthermore, differences in sample size, sensitivity, specificity, and type I and II errors between approaches were explored. Patients received either oral danirixin 75 mg twice daily (n = 45) or placebo (n = 48) on top of standard of care over 52 weeks. A step function best described the COPD symptoms-time course in both trial arms. The IRM improved precision of the estimated drug effect compared to MMRM, resulting in a sample size of 2.5 times larger for the MMRM analysis to achieve the IRM precision. The IRM showed a higher probability of a positive predictive value (34%) than MMRM (22%). An item model–based analysis data gave more precise estimates of drug effect than MMRM analysis for the same endpoint in this one case study. [ABSTRACT FROM AUTHOR]

We describe and compare two methods for the group sequential design of two-arm experiments with Poisson distributed data, which are based on a normal approximation and exact calculations respectively. A framework to determine near-optimal stopping boundaries is also presented. Using this framework, for a considered example, we demonstrate that a group sequential design could reduce the expected sample size under the null hypothesis by as much as 44% compared to a fixed sample approach. We conclude with a discussion of the advantages and disadvantages of the two presented procedures. [ABSTRACT FROM AUTHOR]

David M Mannino,1 Emmanuelle M Clerisme-Beaty,2 Joanne Franceschina,2 Naitee Ting,2 Nancy K Leidy3 1Department of Preventive Medicine and Environmental Health, University of Kentucky College of Public Health, Lexington, KY, USA; 2Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CT, USA; 3Evidera, Bethesda, MD, USA Background: Little is known about the recovery patterns from acute exacerbations of chronic obstructive pulmonary disease (AECOPD) in newly diagnosed or maintenance treatment-naïve patients with COPD. This study describes the course of AECOPD in these patients at the time of treatment for the symptoms of acute respiratory tract infection (RTI). Methods: This study was a secondary analysis of data from a 12-week, randomized clinical trial (TICARI 1) testing the efficacy and safety of once-daily tiotropium 18 µg maintenance therapy versus placebo in newly diagnosed or maintenance treatment-naïve COPD patients with acute RTI symptoms for ≤7 days. Patients received standard care for AECOPD and RTI. Due to under-recruitment, the trial ended early and hence was underpowered to detect treatment differences. Data were pooled and exacerbation recovery patterns examined by using the EXAcerbation of Chronic Pulmonary Disease Tool (EXACT), forced expiratory volume in 1 second, rescue medication use, COPD Assessment Test™, Functional Assessment of Chronic Illness Therapy–Short Form, and Work Productivity and Activity Impairment Questionnaire: Respiratory Symptoms. Results: Of 140 patients, 73.6% had a prior COPD diagnosis without maintenance therapy; 80.0% had moderate-to-severe airflow obstruction. In addition to study drug, 40.0% were prescribed pharmacologic therapy (corticosteroids [34.3%], antibiotics [16.4%], and short-acting β2-adrenergic agonists [5.0%]) within ±7 days of randomization. Over 12 weeks, 78.6% exhibited symptomatic recovery (EXACT score) in a median of 5.0 days. Across all patients, 49.3% recovered without relapse, 29.3% recovered and then relapsed, and 21.4% had persistent symptoms (recovery criteria unmet). Conclusion: A substantial portion of newly diagnosed or maintenance treatment-naïve patients with COPD experience relapse or persistent symptoms following a clinic visit for AECOPD with symptoms of RTI. Whether initiating maintenance therapy could improve outcomes and reduce exacerbation risk requires further study. Keywords: acute respiratory tract infection symptoms, acute exacerbation of chronic obstructive pulmonary disease, AECOPD, COPD Assessment Test™, EXACT, maintenance therapy, pulmonary function, tiotropium

The Qur'an as a book of heaven consists of many vocabulary that each implies meaning in the direction of a particular understanding of their audience. The purpose of the present study is to compare and adapt the two interpretations of al-Mizan and Kabir's interpretation in the approach to the vocabulary, "typing" and "detailed" Some of the results are: disagreements on the verbal implications of some verses or disagreement over the semantic meanings of some of their vocabulary; and In some cases, the sharing of ideas in the explanation of the meaning of the verses, and in other cases, also witnesses the silence and conjunction of each In explaining the meaning of the words of a verse. The use of the two words in relation to Muslims and believers may also indicate that believers have a high degree of cognitive and cognitive knowledge of Muslim subjects. The mission of this research is to explain the above-mentioned issues by relying on first-hand resources and paying attention to new sources by analytical method.

This article influences the quantum based solutions for traditional pattern matching problem, as the quantum machines can accelerate the computation speed by inherently supporting the parallel executions. The problem identifies solution by suggesting effective algorithms, and as per the classical machines several algorithms are qualified and become criterion for other, importantly noted as Knuth Morris Pratt and Boyer Moore which solves such problem in O(M + N) time. A quantum identical pattern matching algorithms are based upon the principle of high speed Grover's quantum search method which searches an element over unstructured database of "N" elements in O(√N) time. The standard quantum algorithm was proposed by Ramesh and Vinay that could obtain computational speed and provides solution in O(√M + √N) time. We review two already existing quantum based exact and approximate pattern matching algorithms and then by combining the logic of both, a new exact pattern matching algorithm is being proposed which overcomes the algorithmic constraints and substantially proves to be equivalently better than the existing classical and quantum benchmark algorithms. So, this article includes existing and proposed quantum pattern matching algorithms, their flowcharts and examples, mathematical justification over complexity analysis. At last we discuss suitable application domains and further possible variations over the proposed work. [ABSTRACT FROM AUTHOR]

Let X be a continuum and let n be a positive integer. We consider the hyperspaces Fn(X) and SFn(X). If m is an integer such that n > m = 1, we consider the quotient space SFn m(X). For a given map f: X ! X, we consider the induced maps Fn(f): Fn(X) ! Fn(X), SFn(f): SFn(X) ! SFn(X) and SFn m(f): SFn m(X) ! SFn m(X). In this paper, we introduce the dynamical system (SFn m(X); SFn m(f)) and we investigate some relationships between the dynamical systems (X; f), (Fn(X);Fn(f)), (SFn(X); SFn(f)) and (SFn m(X); SFn m(f)) when these systems are: exact, mixing, weakly mixing, transitive, totally transitive, strongly transitive, chaotic, irreducible, feebly open and turbulent. [ABSTRACT FROM AUTHOR]

Applications of the pickup and delivery problem with time windows and last-in-first-out (LIFO) loading (PDPTWL) constraints can be found in the transportation of animals, heavyweight goods, and hazardous materials, where unloading vehicles requires more time and special handling. Examples include carrying livestock, cars, and chemical containers. Research on exact methods to solve the pickup and delivery problem with time windows (PDPTW) and its variants has mainly focused on branch-and-price-and-cut algorithms. In this paper, we propose a novel exact approach based on fragments—a series of pickup and delivery requests starting and ending with an empty vehicle. We use fragments to formulate a relaxed network flow model with side constraints. Lazy constraints are used to cut off any illegal solution that may occur while solving the integer program. Extensive computational experiments show that the proposed approach is superior to the current state-of-the-art method. [ABSTRACT FROM AUTHOR]

This paper focuses on development of a new mathematical model and its analytical solution for the buckling analysis of elastic columns with preexisted longitudinal cracks and finite adhesion between the cracked sections. Consequently, the analytical solution for the buckling loads is derived for the first time. The critical buckling loads are calculated for two different types of connections between the cracked sections, namely for slipping only and simultaneous slipping and uplifting between them. The parametric study is performed to analyze the effect of the crack length on the critical buckling loads. It is shown that the critical buckling load can be greatly affected by the crack length and type of the connection between the cracked sections. Finally, the presented results obtained can be used as a benchmark solution. [ABSTRACT FROM AUTHOR]

This paper focuses on development of a new mathematical model and its analytical solution for the buckling analysis of elastic longitudinally cracked columns with finite axial adhesion between the cracked sections. Consequently, the analytical solution for buckling loads is derived for the first time. The critical buckling loads are calculated for different crack lengths and various degrees of the contact adhesion. It is shown that the critical buckling loads can be greatly affected by the crack length and degree of the connection between the cracked sections. Finally, the presented results can be used as a benchmark solution. [ABSTRACT FROM AUTHOR]

This paper focuses on development of a new mathematical model and its analytical solution for buckling analysis of elastic columns weakened simultaneously with transverse open cracks and partial longitudinal delamination. Consequently, the analytical solution for buckling loads is derived for the first time. The critical buckling loads are calculated using the proposed analytical model. A parametric study is performed to investigate the effects of transverse crack location and magnitude, length and degree of partial longitudinal delamination, and different boundary conditions on critical buckling loads of weakened columns. It is shown that the critical buckling loads of weakened columns can be greatly affected by all the analyzed parameters. Finally, the presented results can be used as a benchmark solution. [ABSTRACT FROM AUTHOR]

In this work the exact solution of a problem on stationary solid-state rotation with a constant angular speed of a homogeneous three-axis gas ellipsoid (the law and speed of the movement of the medium and also thermodynamic characteristics of the medium) which is in its own gravitational field and adjoining on emptiness is found (zero pressure on boundary). The exact distribution of gravitational potential in a three-axis homogeneous ellipsoid satisfying Poisson's equation is also found. [ABSTRACT FROM AUTHOR]

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper the approximate solution of coupled burgers equations is obtained by asymptotic MOHAM. The obtained results are compared through tables and graphs. The convergence and residual is plotted. [ABSTRACT FROM AUTHOR]

Pattern matching can be done with the help of bit-parallelism and character-based techniques. Bit-parallelism-based algorithms are currently the fastest and more efficient than other characterbased for both exact and inexact pattern matching. This is due to the use of intrinsic parallelism of the bit operation inside a computer word which allows you to cut down the number of operations that algorithm performs by a factor up to w, where w is the number of bits in the computer word. The paper presents a comparative analysis of well-known bit-parallel matching algorithms such as Shift-Or, Shift-And, Backward Non-Deterministic Matching (BNDM) and two variants of BNDM algorithm. The resulting experimental shift mechanism of BNDM, SBNDM and FSBNDM using bit-parallelism technique is also discussed. [ABSTRACT FROM AUTHOR]

In this paper we mainly discuss the exact K-g-frames in the Hilbert spaces. We use the induced sequence $$\{u_{jk}\}$$ of a g-Bessel sequence $$\{\Lambda _j\}_{j\in J}$$ and an invertible operator to characterize whether $$\{\Lambda _j\}_{j\in J}$$ is an exact K-g-frame or not, we also use the bounded linear operator K and $$l^2(\{{{\mathcal V}_j}\}_{j\in J})$$ -linear independent to characterize the properties of the K-dual sequence of $$\{\Lambda _j\}_{j\in J}$$ . [ABSTRACT FROM AUTHOR]

For a dynamical system , let be its induced dynamical system on the space of Borel probability measures with weak*-topology. It is proved that is -transitive (resp., exact, uniformly rigid) if and only if is weakly mixing and -transitive (resp., exact, uniformly rigid), where is an -vector of integers. Moreover, some analogous results are obtained for the hyperspace. [ABSTRACT FROM AUTHOR]

Although sleep disturbance is common in chronic obstructive pulmonary disease (COPD), relatively little is known on the effect of the exacerbation on sleep quality. Accordingly, we longitudinally assessed sleep variables during exacerbations and clinical stability. This is a sub-study of a larger observational analysis. Inclusion criteria were clinically stable COPD and two or more clinical exacerbations in the preceding 12 months. Patients were followed for approximately 6 months and during this time the following were recorded daily: (1) COPD exacerbations, which were determined in two ways, clinically and symptom defined using the exacerbations of chronic pulmonary disease tool (EXACT); (2) daytime sleepiness, which was measured using the Stanford Sleepiness Scale; (3) subjective awakenings, which was measured from a sleep diary; and (4) sleep duration, efficiency, and objective awakenings, which was measured from actigraphy. These variables for exacerbation and non-exacerbation days were compared. Seventeen patients (9 male, age 63 ± 12 years, forced expiratory volume in 1 second 52 ± 20%) entered data over 135 ± 18 days. During this time, 15 patients had 27 symptom-defined exacerbations and 8 had 9 clinically reported exacerbations. Symptom-defined exacerbation days were 26% of the total study days. More daytime sleepiness, decreased total sleep time (TST), and decreased sleep efficiency (SE) were present during exacerbations compared with clinical stability (p < 0.001). These disturbances tended to be greater during clinically reported exacerbations than during unreported events (p < 0.05). Increased daytime sleepiness, less TST, and poorer SE are present during COPD exacerbations. [ABSTRACT FROM AUTHOR]

We present the connection between the running of the cosmological constant and the estimate of its value in the resummed quantum gravity (RQG) realization of quantum general relativity. We also address in this way some of the questions that have been raised concerning this latter generalization and application of the original prescription of Feynman for the formulation of quantum general relativity. [ABSTRACT FROM AUTHOR]

This article is concerned with ergodic theory for transformations which preserve an infinite measure. In the first part we present an overview of the invertible case with a focus on weakly wandering sequences and their applications to num- ber theory as it has developed over the last fifty years. The second part presents a very preliminary investigation into ex- tending weakly wandering sequences to the non-invertible case. This consists primarily of a few examples which illustrate the complexities which arise in the non-invertible case. [ABSTRACT FROM AUTHOR]

ABSTRACT Many proteins undergo large-scale motions where relatively rigid domains move against each other. The identification of rigid domains, as well as the hinge residues important for their relative movements, is important for various applications including flexible docking simulations. In this work, we develop a method for protein rigid domain identification based on an exhaustive enumeration of maximal rigid domains, the rigid domains not fully contained within other domains. The computation is performed by mapping the problem to that of finding maximal cliques in a graph. A minimal set of rigid domains are then selected, which cover most of the protein with minimal overlap. In contrast to the results of existing methods that partition a protein into non-overlapping domains using approximate algorithms, the rigid domains obtained from exact enumeration naturally contain overlapping regions, which correspond to the hinges of the inter-domain bending motion. The performance of the algorithm is demonstrated on several proteins. Proteins 2015; 83:1054-1067. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The models presented in the literature for the computation by simulation of yield from a rainwater tank are either incorrect or approximate at best. In this paper a general, exact, continuous time model of the operation of rainwater tanks is presented. The operation of a tank is determined by the rainfall runoff and demand distribution functions and the capacity of the tank. The runoff and demand distributions are assumed to satisfy certain reasonable conditions which are satisfied in all cases of practical interest, e.g. when the distributions are described by piecewise constant functions. The yield, spill and volume functions are characterized by equations which, by means of a constructive proof involving mathematical induction, can be shown to have unique solutions. This model can be used to compute the exact yield and spill over any period and the volume at any time during the operation of the tank. Correct discrete time simulation models are derived in the special cases of demand before rain (DBR) or demand after rain (DAR). [ABSTRACT FROM AUTHOR]

We use our resummed quantum gravity approach to Einstein's general theory of relativity in the context of the Planck scale cosmology formulation of Bonanno and Reuter to estimate the value of the cosmological constant such that ρΛ = (0.0024 eV)4. We argue that the closeness of this estimate to experiment constrains Supersymmetric Grand Unified Theory (susy GUT) models. We discuss in turn various theoretical issues that have been raised about the approach itself as well as about the application to estimate the cosmological constant. Given the closeness of the estimate to the currently observed value, we also discuss the theoretical uncertainty in the estimate-at this time, we argue it is still large. [ABSTRACT FROM AUTHOR]

Peer-to-Peer (P2P) computing, the harnessing of idle CPU cycles through the Internet, offers new research challenges in the domain of distributed computing. This paper proposes an efficient, dynamic and scalable overlay orientated towards P2P computing, called DisCoP. Our proposal gathers the peers into markets according to their computational resources. Each market is arranged in an N-ari Tree and these trees are linked by a Bruijn graph. The tree topology allows efficient searching of available resources in a specific market, while the Bruijn provides good scalability. A Hilbert function is used to arrange markets in one ordered and mono-dimensional space. This way, the proposed architecture exploits the Bruijn and the N-ari tree topologies together with the Hilbert function to classify the computing markets. Searching efficiently for computational resources in P2P systems is a challenge and in turn, an essential requirement for the platform to provide. This article also proposes different search algorithms, each adapted to the DisCoP overlay and optimized to locate computing resources in different ways: exact, range, multi-attribute and approximate searches. A large number of experiments demonstrate the correct behavior of our proposals. The comparison of the obtained results obtained compared to other approaches in the literature reveals their competitiveness in terms of efficiency, latency and hit rates. [ABSTRACT FROM AUTHOR]

The electromagnetic scattering of a plane wave by a metallic spheroid is considered in this work. The solution is obtained using two alternative methods: the first method is based on applying asymptotic expansions on the spheroidal eigenvectors, allowing a closed-form solution for the fields and the scattering cross sections, which is valid for small eccentricities of the spheroid. The second method is based on the full wave analysis using the separation of variables in terms of the spheroidal eigenvectors, which allows to obtain the exact solution of the problem. Both prolate and oblate spheroids are considered, and both polarizations are studied. Numerical results are given for various values of the parameters. [ABSTRACT FROM PUBLISHER]

The cutoff wavenumbers of eccentric nonconfocal elliptical metallic waveguides are calculated in this paper. The solution is obtained using expansions in terms of the elliptical wave functions, in combination with the related addition theorem. The method presented here is exact, and allows the study of more complex elliptical waveguide geometries, like rotated elliptical interfaces arbitrarily placed inside the outer elliptical interface, or studies for possible change of the operational bandwidth. The solution is validated compared with other published results from the literature. The known problem of an elliptical metallic waveguide loaded by a concentric nonconfocal strip is revisited and discrepancies noticed by other authors are justified. Numerical results are presented for the cutoff wavenumbers for various composite elliptical waveguides for both TM and TE modes. [ABSTRACT FROM PUBLISHER]

Modeling the conduction of heat in living tissue requires the consideration of sudden spatial discontinuities in property values as well as the presence of the body's circulatoiy system. This paper presents a description of the separation of variables method that results in a remarkably simple solution of transient heat conduction in a perfuse composite slab for which at least one of the layers experiences a zero perfusion rate. The method uses the natural analytic approach and formats the description so that the constants of integration of each composite layer are expressed in terms of those of the previous layer's eigenfunctions. This allows the solution to be "built" in a very systematic and sequential manner. The method is presented in the context of the Pennes bioheat equation for which the solution is developed for a system composed of any number of N layers with arbitrary initial conditions. [ABSTRACT FROM AUTHOR]

We consider the clustered travelling salesman problem in which vertices (except the starting vertex) of the network are divided into some prespecified clusters. The problem is to find a least cost Hamiltonian cycle (tour) in which vertices of any cluster are visited contiguously and the clusters are visited in the prespecified order. The problem is NP-hard and it arises in practical transportation and sequencing problems. This paper develops a lexisearch algorithm for obtaining exact optimal solution to the problem. The efficiency of the algorithm against an existing algorithm to the problem has been examined for asymmetric TSPLIB instances of various sizes and clusters. Finally, we present solutions to some symmetric TSPLIB instances. [ABSTRACT FROM AUTHOR]

Abstract: The principal purpose of the paper is to present an efficient mathematical model for studying the buckling behaviour of geometrically perfect, elastic Reissner’s two-layer composite columns with interlayer slip and uplift between the layers. The present mathematical model is capable of predicting exact critical buckling loads and corresponding buckling modes. Thus, it is used to study the influence of the transverse interlayer stiffness in combination with the longitudinal interlayer stiffness on critical buckling loads and modes. This effect is proved to be significant. The critical buckling loads calculated by the proposed method can be up to approximately 89% smaller than those where interlayer uplift is neglected. [Copyright &y& Elsevier]

The cutoff wavenumbers of the elliptical dielectric waveguide are calculated exactly and analytically. Two separate methods are used to solve this problem. The first method is based on the separation of variables technique using Mathieu functions and gives the exact cutoff wavenumbers. The system matrices of which the roots of their determinant should be determined are complicated because of the nonexistence of orthogonality relations for Mathieu functions, due to the different constitutive parameters between the core and the cladding of the fiber. In the second method, the cutoff wavenumbers are obtained through analytical expressions, when the eccentricity h of the elliptical core is specialized to small values. In the latter case, analytical closed-form algebraic expressions, free of Mathieu functions, are obtained for the expansion coefficients gsn^{(2)} in the resulting relation x1,sn(h)=x1,sn(0)[1+gsn^{(2)}h^{2}+{\cal O}(h^{4})] for the cutoff wavenumbers, where x1,sn(0) are the normalized cutoff wavenumbers of the circular dielectric waveguide. These expressions are valid for every different value of s and n, corresponding to every higher order hybrid mode. Numerical results are given for various higher order modes, as well as a comparison with the exact solution. [ABSTRACT FROM PUBLISHER]

Abstract: To provide desired stiffness and strength in torsion, bridge superstructures are often constructed with a cross-section consisting of multiple cells which have thin walls relative to their overall dimensions and resist Saint–Venant torsion through shear flow (force per unit length) that develops around the cell walls. For a single thin-walled cell subject to torsion, shear flow is constant along each of its walls while shear stresses vary around the section based upon changes in wall thickness. When the cross-section contains multiple cells they all contribute resistance to applied torsion and for elastic continuity each cell must twist the same amount. With these considerations, equilibrium and compatibility conditions allow simultaneous equations to be formed and solved to determine the shear flow for each cell. A second approach is a relaxation method that distributes incremental shear flows back and forth between cells, reducing errors with each distribution cycle, until the final shear flows for all cells approximate the correct values. A major advantage to this method is that it does not require setting up and solving simultaneous equations, favoring situations where hand calculation is desired. In this paper, a closed-form approach is introduced to determine, exactly, both the torsional constant and all shear flows for multi-cell cross-sections under torsion; no simultaneous equations are required and there is no need to distribute shear flows back and forth between cells. Simple closed-form equations are derived which give shear flows for cross-sections with any number of cells of arbitrary shape. [Copyright &y& Elsevier]

Abstract: Shear deformations can affect final member-end-moments for statically indeterminate continuous beams and frame structures, though for typical civil engineering structures their effect is small and moments can be based on flexural deformations only. When a member is deep relative to span length, however, shear deformations should be considered in the analysis. This can be included in the stiffness method and in a modified form of moment distribution where the carry-over factor is less than one-half due to the added flexibility from shear. In a prior paper the first author presented a new approach for solving statically indeterminate beams and bridge frames, with final end moments given in closed-form expressions. The advantages of this new approach are that no simultaneous equations are required as in the stiffness method, moments are not distributed back and forth as in moment distribution, and manual calculations may be used which give exact results for as many spans as desired. While only flexural deformations were considered in the original paper, this paper presents a closed-form approach that has been modified to include shear deformations. Final expressions are given for continuous beams and bridge frames, providing exact member-end-moments that match results from the stiffness method when shear deformations are included in the analysis. [Copyright &y& Elsevier]

Abstract: A mathematical model for a slip-buckling problem has been proposed and its exact solution has been found for the analysis of materially inelastic two-layer composite columns with non-linear interface compliance. The mathematical model has been carried out to evaluate exact critical buckling loads. It has been demonstrated mathematically exactly, that exact critical buckling loads are influenced by the initial stiffness, and hence on linear portion of the interface force-slip relationship. Besides, it has been shown that material inelasticity can reduce the critical buckling loads significantly and that the interlayer stiffness has an important effect on the transition between the elastic and inelastic buckling. [Copyright &y& Elsevier]

Abstract: An exact solution method is given for 3D heating over a rectangular region on a homogeneous plate. It has application to laser heating and cooling of electronic equipment. Based on Green’s functions and new summation identities, significant improvements are given over the separation of variables method. Machine accuracy is possible, which can be used to both provide verification solutions and intrinsic verification. Basic building blocks for arbitrary space/time heat flux distributions and simplified expressions are provided. The method can also be used for many other boundary conditions using tabulated algebraic identities for summations. [Copyright &y& Elsevier]

A recent article (Santner et al., 2007) asserted that a score interval for a difference of independent binomial proportions (Miettinen and Nurminen, 1985) may have inadequate coverage. We re-visit the properties of score intervals for binomial proportions and their differences. Published data indicate these methods produce mean coverage slightly above the nominal confidence level 1 − α. We argue it is appropriate to align mean rather than minimum coverage with 1 − α, based on a moving average representation of the coverage probability. The poor coverage properties claimed by Santner et al. (2007) actually relate to an inferior version of the score interval (Mee, 1984). [ABSTRACT FROM AUTHOR]

Abstract: Moment distribution continues to be a valuable structural analysis tool for spot-checking member-end-moments of continuous beams and frame structures from computer results. Prior to the widespread use of mainframe and, later, personal computers in the 1980s and 1990s, moment distribution provided a simple hand method for practicing civil engineers to analyze and design statically indeterminate structures, since its public introduction in the early 1930s by Hardy Cross, directly leading to new types of designs and construction. The chief benefits of this method of analysis over the other available methods are that (1) member-end-moments are found directly from the applied loads without first determining various displacement components, (2) no simultaneous equations need to be formed and solved, (3) it is easy to remember and apply, (4) an approximate solution can be obtained at any stage in the analysis and (5) a remarkable variety of statically indeterminate structures can be solved by hand. While the development and introduction of moment distribution represents a great advancement in the history of structural engineering, the distribution process can be tedious, especially if only a few final member-end-moments of a multi-redundant structure are desired. Additionally, when results are wanted to a greater accuracy, the number of distribution cycles required and the number of significant figures that must be carried through the process make it a daunting procedure. In this paper, a new method is presented that gives exact member-end-moments for continuous beams and bridge structures, without the need to distribute moments back and forth as in moment distribution or to set up and solve simultaneous equations, as with the stiffness method. It is anticipated that the primary application of the proposed method will be to spot-check computer results. [Copyright &y& Elsevier]