7,844 research outputs found

    Orthogonal Polynomials with a Singularly Perturbed Airy Weight

    Full text link
    We study the monic orthogonal polynomials with respect to a singularly perturbed Airy weight. By using Chen and Ismail's ladder operator approach, we derive a discrete system satisfied by the recurrence coefficients for the orthogonal polynomials. We find that the orthogonal polynomials satisfy a second-order linear ordinary differential equation, whose coefficients are all expressed in terms of the recurrence coefficients. By considering the time evolution, we obtain a system of differential-difference equations satisfied by the recurrence coefficients. Finally, we study the asymptotics of the recurrence coefficients when the degrees of the orthogonal polynomials tend to infinity.Comment: 16 page

    A novel fuzzy adaptive teaching–learning‑based optimization (FATLBO) for solving structural optimization problems

    Get PDF
    This paper presents a new optimization algorithm called fuzzy adaptive teaching–learning-based optimization (FATLBO) for solving numerical structural problems. This new algorithm introduces three new mechanisms for increasing the searching capability of teaching–learning-based optimization namely status monitor, fuzzy adaptive teaching–learning strategies, and remedial operator. The performance of FATLBO is compared with well-known optimization methods on 26 unconstrained mathematical problems and five structural engineering design problems. Based on the obtained results, it can be concluded that FATLBO is able to deliver excellence and competitive performance in solving various structural optimization problems

    Modeling the Permanent Deformation Behavior of Asphalt Mixtures Using a Novel Hybrid Computational Intelligence

    Get PDF
    One of the main causes of pavement rutting is the repetitive action of traffic loads which results in the accumulation of permanent deformations. As a result, it is important to understand the characteristics of the permanent deformation behavior of asphalt mixes under repeated loading and to build the accurate mix model before they are placed in roadways. This study proposed a hybrid computational intelligence system named SOS-LSSVM for modelling the permanent pavement deformation behavior of asphalt mixtures. The SOS-LSSVM fuses Least Squares Support Vector Machine (LSSVM) and Symbiotic Organisms Search (SOS). LSSVM is employed for establishing the relationship model between the flow number, which is obtained from the laboratory test, and the parameters of the asphalt mix design. SOS is used to find the best LSSVM tuning parameters. A total 118 historical cases were used to establish the intelligence prediction model. Obtained results validate the ability of SOS-LSSVM to model the pavement rutting behavior of asphalt mixture with a relatively high accuracy measured by four error indicators. Therefore, the proposed computational intelligence systems can offer a high benefit for road designers and engineers in decision-making processes

    Differential and Difference Equations for Recurrence Coefficients of Orthogonal Polynomials with a Singularly Perturbed Laguerre-type Weight

    Full text link
    We are concerned with the monic orthogonal polynomials with respect to a singularly perturbed Laguerre-type weight. By using the ladder operator approach, we derive a complicated system of nonlinear second-order difference equations satisfied by the recurrence coefficients. This allows us to derive the large nn asymptotic expansions of the recurrence coefficients. In addition, we also obtain a system of differential-difference equations for the recurrence coefficients

    Modified basket plate for inferior patellar pole avulsion fractures—A report of three cases

    Get PDF
    AbstractIn patients who have sustained an avulsion fracture of the inferior patellar pole, the extensor mechanism is disrupted and should be repaired. The normal height of the patella can be maintained by preserving the patellar pole, but fractures of the inferior pole of the patella are not easy to reduce and fix firmly. In contrast with partial patellectomy, which requires postoperative immobilization, internal fixation with a basket plate allows for immediate mobilization and early weight-bearing. Owing to the unavailability of the basket plate in Taiwan, we have modified the plate with the titanium mesh as a possible alternative. We present three cases of this modified basket plate, which took place between 2008 and 2010. This technique avoided long-term immobilization of the knee with good clinical results

    Society Exchange Characteristics, Service Quality, and Relationship Quality between Hospital and Its Suppliers

    Get PDF
    Successful supply chain management provides an enterprise with a new competitive advantage. However, successful supply chain performance is based on a high level of trust and strong commitment among supply chain partners. Studies have indicated that communication, partner’s reputation, perceived benefits, fairness, and relationship tenure that are within the context of social exchange theory have an effect on trust. In the current study, we attempted to integrate two types of theories of social exchange and service quality by proposing an integrated model that influences the factor to trust and commitment. We then applied structural equation modeling to test the model. The study results indicated that a hospital’s trust in its supply chain partner is highly associated with commitment. The study included respondents comprising medical device procurement staff working in hospitals within Taiwan. A total of 500 questionnaires were distributed; 316 completed questionnaires were received. The results revealed that communication, partner’s reputation, and perceived benefits had a positive effect on trust. Service quality was also determined to have a positive effect on trust and commitment. This result should provide reference for a hospital and its relationship with suppliers, which helps monitor decision variables in the supply chain management of medical devices

    A Novel Implementation of Nature-inspired Optimization for Civil Engineering: A Comparative Study of Symbiotic Organisms Search

    Get PDF
    The increasing numbers of design variables and constraints have made many civil engineering problems significantly more complex and difficult for engineers to resolve in a timely manner. Various optimization models have been developed to address this problem. The present paper introduces Symbiotic Organisms Search (SOS), a new nature-inspired algorithm for solving civil engineering problems. SOS simulates mutualism, commensalism, and parasitism, which are the symbiotic interaction mechanisms that organisms often adopt for survival in the ecosystem. The proposed algorithm is compared with other algorithms recently developed with regard to their respective effectiveness in solving benchmark problems and three civil engineering problems. Simulation results demonstrate that the proposed SOS algorithm is significantly more effective and efficient than the other algorithms tested. The proposed model is a promising tool for assisting civil engineers to make decisions to minimize the expenditure of material and financial resources
    • …
    corecore