Usual Operations Research Articles

Two-way deterministic automata with jumping mode

The recently introduced one-way jumping automata are strictly more powerful than classical finite automata (FA) while maintaining decidability in most of the important cases. We investigate the extension of the new processing mode to two-way deterministic finite automata (2DFA), resulting in deterministic finite automata which can jump to the nearest letter which they can read, with jumps allowed in either direction. We show that two-way jumping automata are strictly more powerful than one-way jumping ones and that alternative extensions of 2DFA with this jumping mode lead to equivalent machines. We also prove that the class of languages accepted by the new model is not closed under the usual language operations. Finally we show how one could change the model to terminate on every input by using non-erasable end markers.

Image Edge Detection: A New Approach Based on Fuzzy Entropy and Fuzzy Divergence

In image pre-processing, edge detection is a non-trivial task. Sometimes, images are affected by vagueness so that the edges of objects are difficult to distinguish. Hence, the usual edge-detecting operators can give unreliable results, thus necessitating the use of fuzzy procedures. In literature, Chaira and Ray approach is a popular technique for fuzzy edge detection in which fuzzy divergence formulation is exploited. However, this approach does not specify the threshold technique must be applied. Then, in this work, starting from Chairy and Ray procedure, we present a new fuzzy edge detector based on both fuzzy divergence (thought and proved to be a distance) and fuzzy entropy minimization for the thresholding sub-step in gray-scale images. Eddy currents, thermal infrared, and electrospinning images were used to test the proposed procedure after their fuzzification by a suitable adaptive S-shaped fuzzy membership function. Moreover, the fuzziness content of each image has been quantified by new specific indices proposed here and formulated in terms of fuzzy divergence. The results have been evaluated by suitable assessment metrics here formulated and are considered to be encouraging when qualitatively and quantitatively compared with those obtained by some well-known I- and II-order edge detectors.

Stability and existence results for a class of nonlinear parabolic equations with three lower order terms and measure data using Lorentz spaces

We study both existence and stability of renormalized solutions for nonlinear parabolic problems with three lower order terms that have, respectively, growth with respect to u and to the gradient, whose model $$\begin{aligned}({\mathcal {P}})\ {\left\{ \begin{array}{ll} u_{t}-\varDelta _{p}u-\text {div}[c(t,x)|u|^{\gamma -1}u]+b(t,x)|\nabla u|^{\lambda }+d(t,x)|u|^{\iota }=\mu -\text {div}(E)\quad \text { in }Q,\\ u(0,x)=u_{0}(x) \quad \text { in }\varOmega ,\ u(t,x)=0\text { on }(0,T)\times \partial \varOmega , \end{array}\right. }\end{aligned}$$ where $$Q:=(0,T)\times \varOmega $$ (with $$\varOmega $$ is an open bounded subset of $${\mathbb {R}}^{N}$$ ( $$N\ge 2$$ ) and $$T>0$$ ), $$1<p<N$$ , $$\varDelta _{p}$$ is the usual p-Laplace operator, and $$\mu \in {\mathbf {M}}(Q)$$ is a (general) measure with bounded total variation on Q. As a consequence of our main results, we prove that the conditions $$\gamma =\frac{(N+2)(p-1)}{N+p}$$ , $$\lambda =\frac{N(p-1)+p}{N+2}$$ , $$0\le \iota \le p-\frac{N-p}{N}$$ , $$c\in L^{\tau =\frac{N+p}{p-1}}(Q)^{N}$$ , $$b\in L^{N+2,1}(Q)$$ and $$d\in L^{z',1}(Q)$$ (with $$z=\frac{pN-N-p}{\iota N}$$ ) are necessary and sufficient for the existence and the stability of solutions for every sufficiently regular $$u_{0}\in L^{2}(\varOmega )$$ , $$E\in L^{p'}(Q)^{N}$$ and irregular $$\mu \in {\mathbf {M}}(Q)$$ .

Time-dependent acoustic scattering from generalized impedance boundary conditions via boundary elements and convolution quadrature

Abstract Generalized impedance boundary conditions are effective approximate boundary conditions that describe scattering of waves in situations where the wave interaction with the material involves multiple scales. In particular, this includes materials with a thin coating (with the thickness of the coating as the small scale) and strongly absorbing materials. For the acoustic scattering from generalized impedance boundary conditions, the approach taken here first determines the Dirichlet and Neumann boundary data from a system of time-dependent boundary integral equations with the usual boundary integral operators, and then the scattered wave is obtained from the Kirchhoff representation. The system of time-dependent boundary integral equations is discretized by boundary elements in space and convolution quadrature in time. The well-posedness of the problem and the stability of the numerical discretization rely on the coercivity of the Calderón operator for the Helmholtz equation with frequencies in a complex half-plane. Convergence of optimal order in the natural norms is proved for the full discretization. Numerical experiments illustrate the behaviour of the proposed numerical method.

Investigation towards surface roughness & material removal rate in Wire-EDM of aluminium alloy 6061 and 5083 using Taguchi method

Wire-electro discharge machining (WEDM) is a spark degeneration operation utilized for creating intricate patterns and profiles by means of electrically conductive materials employing wire electrode. The level of exactness and fine surface completions of the work-piece is important for the uses of particular complex segments. Other than WEDM, the manufacturing of accurate shapes and dimensions requires a lot of hours by a usual operations. Surface roughness together with material removal rate in WEDM is of critical significance. The current investigation exhibits, the impact of WEDM specifications about surface roughness plus material removal rate on aluminium alloy (AA) 6061 and aluminium alloy (AA) 5083 are explored and single objective method is utilized for parametric optimization. The study utilizes Taguchi's robust design methodology by considering, orthogonal matrix L9, S/N ratio, and ANOVA. For experimentation, pulse on time, pulse off time as well as peak current are utilized as primary variable numeric. The outcomes show that the major important elements that influence the surface roughness are Pulse on time together with Pulse off time in case of AA 6061 likewise the major important elements that influence the surface roughness are pulse off time with peak current in case of AA 5083.

ОБ АДДИТИВНОЙ МОДИФИКАЦИИ γ-СВОЙСТВА

The aim of this article is to modify the notion of the γ-property so that the modified property is preserved under taking a direct topological sum. To this end, we use a procedure of “saturation” of ω-covers of topological spaces. Namely, we add to each ω-cover the family of all unions of its subfamilies consisting of at most k elements (“k-saturation”), or the family of all unions of its finite subfamilies (“saturation”). Thus, we obtain for Tychonoff spaces a sequence ( k )k&lt;ω γ′ of covering properties such that k k +1 ′ ′ γ ⇒ γ for any integer k, and 1 ′γ is the well-known γ-property. Also, the property ωγ′ such that k ω γ′ ⇒ γ′ for any integer k is obtained. It is proved that each kγ′ -property is preserved under usual topological operations, namely, taking closed subspaces, continuous images, and finite powers. It is known that the classical γ-property can be failed under passing to topological sum. Our main result means that it is impossible with respect to whole sequence ( k )k&lt;ω γ′ . More precisely, if a space X satisfies kγ′ , Y satisfies mγ′ , then the sum X ⊕Y satisfies k +m γ′ . Nevertheless, X ⊕ X satisfies kγ′ as X itself. As another main result, we establish that the ωγ′ -property and the Lindelöf property are equivalent. It follows that any countable union of spaces Xn with the k (n) γ′ -property is a Lindelöf space.

New estimates for the numerical radius

In this article, we present new inequalities for the numerical radius of the sum of two Hilbert space operators. These new inequalities will enable us to obtain many generalizations and refinements of some well known inequalities, including multiplicative behavior of the numerical radius and norm bounds. Among many other applications, it is shown that if T is accretive-dissipative, then 1/?2 ||T|| ? ?(T), where ?(?) and ||?||denote the numerical radius and the usual operator norm, respectively. This inequality provides a considerable refinement of the well known inequality 1/2 ||T|| ? ?(T).

The model declaratory action in the German Civil Procedure Act

The model declaratory action was established in the Chapter 6 of the German Civil Procedure Act when the act was partially amended on July 12th, 2018. Articles 606 through 614, nine articles in total, governs this type of action. The revised German Civil Procedure Act entered into effect on November 1st, 2018. During the past two years, seven cases including the Volkswagen case and the Auto loan bank case has been resolved or pending at the court. To summarize, the model declaratory action in Germany allows plaintiffs in collective dispute to seek individual relief such as damages. In 2001, approximately 17,000 investors individually filed lawsuits regarding the so-called “Deutsche Telecom investment fund case”, and such massive lawsuit filings almost disabled usual operations of the courts. As a response to this, German lawmakers revised the Capital Investor - Model Procedure Act (Kapitalanleger - Musterfahrengesetz, abbreviated as “KapMug”) and established the model procedure only in the collective disputes regarding capital investment. The model procedure was entered into the effect on November 1, 2005 and the effect was expired on the pre-determined expiration date, November 1, 2020. As effects of the model procedure under the Capital Investor - Model Procedure Act expires, to redress collective disputes in all areas, German lawmakers established the model declaratory action in the Chapter 6 of the German Civil Procedure Act by significantly improving existing model procedure. This article closely evaluates German model declaratory action by reviewing its Concept(definition and legal characteristics, Chapter II), Requirements(Chapter III), Contents and publication of the complaint and litigation procedure(Chapter IV), Settlement while the model declaratory action is pending(Chapter V), and Judgments, Appeals, and Effects of the judgments(Chapter VI), based on the texts of the Articles 606 through 614 of the German Civil Procedure Act. German model declaratory action endows a group in German ‘litigation by a group’ with standing as a plaintiff. By doing so, the group may have a judgment regarding causes of the collective dispute from the High court having jurisdiction for all consumers. Then it is regarded that individual consumers who were registered on litigation registry of the model declaratory action can enforce the effects of the judgment. Based on the judgment of the model declaratory action, the registered consumer can claim damages in his or her individual litigation by proving amounts of damages occurred to him or her. German model declaratory action is distinguished from Class-action in the U.S. in that the German procedure is not an one-step dispute resolution that include litigation procedure and enforcement procedure. Rather, in German model declaratory action, a qualified group files a lawsuit and receives a judgment; and later an individual consumer files individual litigations, receives his or her own judgments, and enforce the individual judgment. This article evaluates establishment of German model declaratory action as a developing its own way of dispute resolution.

Modeling and prediction of the average roughness of UNS S31600 in superfinishing turning

PurposeThe purpose of this paper is to realize an effective hybrid modeling (empirical-geometric) in order to describe the real behavior of the average roughness variation of the workpiece surface in turning with an elementary operation of superfinishing, using different analytic methodologies. The previous works are limited to describe the roughness for the usual elementary operations, citing the roughing and the semi-finishing, while this analysis builds technical rails for the industrialists in order to well conduct the operation of superfinishing in turning, by choosing the cutting parameters from the proposed model.Design/methodology/approachA statistical analysis of the average roughness measurements capability study, by the statistical process control method SPC and the ANN artificial neuron network, Levenberg–Marquardt's methods modified Monte Carlo SRM response surface.FindingsThe objective of this work was to describe the average roughness generated by the penetration of the cutting tool into a part in superfinishing turning. First, the authors used artificial colony analysis to determine optimal cutting conditions in order to have an average roughness lower than 0.8 µm. The cutting conditions selected: (1) the feed rate f ϵ [0.05; 0.2] mm/rev; (2) the pass depth ap ϵ [0.25; 1] mm; (3) the corner radius re = 0.2 mm and (4) cutting speed Vc ϵ [75; 100] m/min.Originality/valueThis work consists to realize an effective hybrid modeling (empirical-geometric) in order to describe the real behavior of the average roughness variation of the workpiece surface in turning with an elementary operation of superfinishing, using different analytic methodologies. The previous works are limited to describe the roughness for the usual elementary operations, citing the roughing and the semi-finishing, while this analysis builds technical rails for the industrialists in order to well conduct the operation of superfinishing in turning, by choosing the cutting parameters from the proposed model.

Lower Semi-frames, Frames, and Metric Operators

This paper deals with the possibility of transforming a weakly measurable function in a Hilbert space into a continuous frame by a metric operator, i.e., a strictly positive self-adjoint operator. A necessary condition is that the domain of the analysis operator associated with the function be dense. The study is done also with the help of the generalized frame operator associated with a weakly measurable function, which has better properties than the usual frame operator. A special attention is given to lower semi-frames: indeed, if the domain of the analysis operator is dense, then a lower semi-frame can be transformed into a Parseval frame with a (special) metric operator.

Generalized fractional integral operators on Orlicz–Hardy spaces

AbstractThe generalized fractional integral operators are shown to be bounded from an Orlicz–Hardy space to another Orlicz–Hardy space , where Φ and Ψ are generalized Young functions. The result extends the boundedness of the usual fractional integral operator from to for and , which was proved by Stein and Weiss in 1960.

The Continuous Primitive Integral in the Plane

An integral is defined on the plane that includes the Henstock-Kurzweil and Lebesgue integrals (with respect to Lebesgue measure). A space of primitives is taken as the set of continuous real-valued functions \(F(x,y)\) defined on the extended real plane \([-\infty,\infty]^2\) that vanish when \(x\) or \(y\) is \(-\infty\). With usual pointwise operations this is a Banach space under the uniform norm. The integrable functions and distributions (generalised functions) are those that are the distributional derivative \(\partial^2/(\partial x\partial y)\) of this space of primitives. If \(f=\partial^2/(\partial x\partial y) F\) then the integral over interval \([a,b]\times [c,d] \subseteq[-\infty,\infty]^2\) is \(\int_a^b\int_c^d f=F(a,c)+F(b,d)-F(a,d)-F(b,c)\) and \(\int_{-\infty}^\infty \int_{-\infty}^\infty f=F(\infty,\infty)\). The definition then builds in the fundamental theorem of calculus. The Alexiewicz norm is \({\lVert f\rVert}={\lVert F\rVert}_\infty\) where \(F\) is the unique primitive of \(f\). The space of integrable distributions is then a separable Banach space isometrically isomorphic to the space of primitives. The space of integrable distributions is the completion of both \(L^1\) and the space of Henstock-Kurzweil integrable functions. The Banach lattice and Banach algebra structures of the continuous functions in \({\lVert \cdot\rVert}_\infty\) are also inherited by the integrable distributions. It is shown that the dual space is the functions of bounded Hardy-Krause variation. Various tools that make these integrals useful in applications are proved: integration by parts, Hölder’s inequality, second mean value theorem, Fubini’s theorem, a convergence theorem, change of variables, convolution. The changes necessary to define the integral in \({\mathbb R}^n\) are sketched out.

Time-dependent pseudo-bosonic coherent states

In order to construct time-dependent pseudo-bosonic coherent states, first, we extend the non-Hermitian integrals of motion method to cases where the quantum systems are described by time-dependent non-Hermitian Hamiltonians; second, we introduce a pseudo-bosonic annihilation operator defined as a time-dependent non-Hermitian linear invariant. The pseudo-bosons operators are a pseudo-Hermitian extension of usual boson operators. In fact, they are obtained from the modification of usual boson commutation relations where the annihilation and creation operators are related to their adjoint operators via the bounded Hermitian invertible operator or metric operator. Thus, the pseudo-bosonic coherent states are just obtained as eigenstates of the pseudo-bosonic annihilation operator. As an illustration, we study the time-dependent non-Hermitian Swanson Hamiltonian and we compare the obtained results with those in the literature (Swanson model but time-independent).

Acceder a la gestión de lo simbólico. Un derecho ciudadano

Significar el espacio urbano es una de las actividades más relevantes para permitir su conversión en espacio público, en convertir los sitios en lugares. Para ello es imprescindible ampliar el concepto de “accesibilidad” al nivel de la “accesibilidad simbólica” y entenderla como uno de los nuevos derechos urbanos.El artículo desarrolla los conceptos de “simbolismo a priori” y “simbolismo a posteriori” como estrategias de intervención de significación del espacio público. El primero responde a las operaciones habituales desde la administración, el segundo a los procesos populares de apropiación del espacio.Analizando la experiencia de participación creativa – hoy en curso- en el barrio barcelonés del Bon Pastor el artículo plantea la posibilidad de creación de un lugar de encuentro entre los dos tipos de simbolismo, mediante procesos de co-producción del espacio público, específicamente de su co-diseño.

The Fight Against the COVID-19 Pandemic With 5G Technologies

The coronavirus disease (COVID-19) pandemic has affected the world in an unexpected manner. The human race is battling against the pandemic while schools, universities, industries, hospitals, and governments are seeking new methods and technologies to seamlessly continue their usual operations. In response, this article presents how 5G and Internet of Things (IoT) related technologies can be efficiently utilized and developed to fight against the COVID-19 pandemic. Several use-cases on how 5G and IoT can be enablers to provide innovative solutions in the areas of telehealth, contact tracing, education, retail and supply chains, e-government/ remote office/ information sharing, smart manufacturing and factory automation, e-tourism, and entertainment are presented along with their technical requirements and challenges. It is envisaged that the proposed solutions will be instrumental to facilitate the usual lifestyle, work, and other day-to-day activities of humans in the postpandemic world.

Norm and numerical radius inequalities for Hilbert space operators

ABSTRACT We give several norm and numerical radius inequalities for Hilbert space operators. These inequalities improve on some earlier related inequalities. As an application of one of our results, we give a necessary condition for the equality case in the triangle inequality for the usual operator norm.

A Cloud-Ready Architecture for Shared Medical Imaging Repository.

Nowadays usage paradigms of medical imaging resources are requesting vendor-neutral archives, accessible through standard interfaces, with multi-repository support. Regional repositories shared by distinct institutions, tele-radiology as a service at cloud, teaching, and research archives are illustrative examples of this new reality. However, traditional production environments have a server archive instance per functional domain where every registered client application has access to all studies. This paper proposes an innovator ownership concept and access control mechanisms that provide a multi-repository environment and integrates well with standard protocols. A secure accounting mechanism for medical imaging repositories was designed and instantiated as an extension of a well-known open-source archive. A new web service layer was implemented to provide a vendor-neutral solution compliant with modern DICOM Web protocols for storage, search, and retrieval of medical imaging data. The concept validation was done through the integration of proposed architecture in an open-source solution. A quantitative assessment was performed for evaluating the impact of the mechanism in the usual DICOM Web operations. This article proposes a secure accounting architecture able to easily convert a standard medical imaging archive server in a multi-repository solution. The proposal validation was done through a set of tests that demonstrated its robustness and usage feasibility in a production environment. The proposed system offers new services, fundamental in a new era of cloud-based operations, with acceptable temporal costs.

Analytic solutions for a modified fractional three wave interaction equations with conformable derivative by unified method

The present work implements the unified method to a class of fractional partial differential systems corresponding to modified fractional three wave interaction equations (FTWIEs). The fractional derivative of the three waves envelopes is considered under the conformable sense. The conformable FTWIEs is derived in the (3 + 1) dimensions under the conformable time-fractional derivative of order α∈(0,1] based on a modification of the Lax-pair created by Zakharov-Manakov which includes three-dimensional velocity vector dotted with the usual del operator. Then, the unified method for creating solutions for nonlinear evolution FTWIEs is applied. Subsequently, a systematic algorithm is used to obtain an infinite set of exact rational solutions to the novel constructed system. By randomly selecting the special values for the parameters, three-dimensional graphs are also given for different patterns. The obtained solutions might play an essential role in many other nonlinear evolution equations that occur in the fields of engineering and mathematical physics.

Better bounds on the numerical radii of Hilbert space operators

Kittaneh proved that if A is a bounded linear operator on a complex Hilbert space, then14‖|A|2+|A⁎|2‖≤ω2(A), where ω(⋅) and ‖⋅‖ are the numerical radius and the usual operator norm, and |A|=(A⁎A)1/2. In this paper, we show that14‖|A|2+|A⁎|2‖≤12ω2(A)+18‖(A+A⁎)(A−A⁎)‖≤ω2(A).Meanwhile, we give an improvement of the norm inequality presented by Bhatia and Kittaneh for the positive operators.

Equivalent metrics on normal composition operators

We define some metrics on the set of all bounded normal composition operators in L2(Σ), and show that these metrics are equivalent with the metric induced by the usual operator norm.