Application of the dual reciprocity boundary integral equation technique to solve the nonlinear Klein-Gordon equation

This paper aims to obtain approximate solutions of the Nonlinear Klein-Gordon (NLKG) equation by employing the Boundary Integral Equation (BIE) method and the Dual Reciprocity Boundary Element Method (DRBEM). This method is improved by using a predictor-corrector scheme to the nonlinearity which appears in the problem. We employ the time stepping scheme to approximate the time derivative, and the Linear Radial Basis Functions (LRBFs), are used in the Dual Reciprocity (DR) technique. To confirm the accuracy of the new approach, the numerical results of a Double-Soliton and a problem with inhomogeneous terms are compared with analytical solutions and for the examples possessing single and periodic waves, two conserved quantities associated to the (NLKG) equation, the energy and the momentum are investigated.     

Dynamics of the difference equation

We study the invariant interval, the character of semicycles, the global stability, and the boundedness of the difference equation

where the initial conditions x_−k,…,x₋₁,x₀ are nonnegative, and p,q>0.     

Substrate‐integrated waveguide band pass filters with frequency‐dependent coupling elements

An effective technique to improve the stop‐band frequency response of direct‐coupled resonators in substrate‐integrated waveguide (SIW) technology is introduced. Regular inductive‐iris filters in SIW technology are supplemented with H‐plane frequency‐dependent inverters which not only create transmission zeros but also serve as the proper impedance inverter. A synthesis technique is introduced to prescribe transmission zeros at finite frequencies on either side of the pass band, symmetrically or asymmetrically. Two different topologies of frequency‐dependent inverters for X‐band SIW band pass filters demonstrate that attenuation poles can be created on both side of the passband and significantly improve the filters' stop‐band performences. Measurements confirm the validity of the presented design approach. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:237–242, 2014.     

Semantic schema modeling for genetic programming using clustering of building blocks

Semantic schema theory is a theoretical model used to describe the behavior of evolutionary algorithms. It partitions the search space to schemata, defined in semantic level, and studies their distribution during the evolution. Semantic schema theory has definite advantages over popular syntactic schema theories, for which the reliability and usefulness are criticized. Integrating semantic awareness in genetic programming (GP) in recent years sheds new light also on schema theory investigations. This paper extends the recent work in semantic schema theory of GP by utilizing information based clustering. To this end, we first define the notion of semantics for a tree based on the mutual information between its output vector and the target and introduce semantic building blocks to facilitate the modeling of semantic schema. Then, we propose information based clustering to cluster the building blocks. Trees are then represented in terms of the active occurrence of building block clusters and schema instances are characterized by an instantiation function over this representation. Finally, the expected number of schema samples is predicted by the suggested theory. In order to evaluate the suggested schema, several experiments were conducted and the generalization, diversity preserving capability and efficiency of the schema were investigated. The results are encouraging and remarkably promising compared with the existing semantic schema.     

An efficient routing algorithm to preserve k-coverage in wireless sensor networks

One of the major challenges in the area of wireless sensor networks is simultaneously reducing energy consumption and increasing network lifetime. Efficient routing algorithms have received considerable attention in previous studies for achieving the required efficiency, but these methods do not pay close attention to coverage, which is one of the most important Quality of Service parameters in wireless sensor networks. Suitable route selection for transferring information received from the environment to the sink plays crucial role in the network lifetime. The proposed method tries to select an efficient route for transferring the information. This paper reviews efficient routing algorithms for preserving k-coverage in a sensor network and then proposes an effective technique for preserving k-coverage and the reliability of data with logical fault tolerance. It is assumed that the network nodes are aware of their residual energy and that of their neighbors. Sensors are first categorized into two groups, coverage and communicative nodes, and some are then re-categorized as clustering and dynamic nodes. Simulation results show that the proposed method provides greater efficiency energy consumption.     

Network analyses of Y-chromosomal types in Europe, northern Africa, and western Asia reveal specific patterns of geographic distribution

In a study of 908 males from Europe, northern Africa, and western Asia, the variation of four Y-linked dinucleotide microsatellites was analyzed within three "frames" that are defined by mutations that are nonrecurrent, or nearly so. The rapid generation and extinction of new dinucleotide length variants causes the haplotypes within each lineage to diverge from one another. We constructed networks of "adjacent" haplotypes within each frame, by assuming changes of a single dinucleotide unit. Two small and six large networks were obtained, the latter including 94.9% of the sampled Y chromosomes. We show that the phenetic relationships among haplotypes, represented as a network, result largely from common descent and subsequent molecular radiation. The grouping of haplotypes of the same network thus fits an evolutionarily relevant criterion. Notably, this method allows the total diversity within a sample to be partitioned. Networks can be considered optimal markers for population studies, because reliable frequency estimates can be obtained in small samples. We present synthetic maps describing the incidence of different Y-chromosomal lineages in the extant human populations of the surveyed areas. Dinucleotide diversity also was used to infer time intervals for the coalescence of each network.     

Cecal infarct: report of a case

PURPOSE: The purpose of this article is to present a case of an uncommon opportunistic fungal infection that appears in immunologically or metabolically compromised patients and is usually fatal. METHOD: A 54-year-old woman with an acute lymphoblastic leukemia had acute abdominal pain with peritoneal symptoms during her hospital stay. A laparotomy was performed and a cecal infarct firmly adherent to about 30 cm of infiltrated jejunal loop was discovered. RESULTS: Microscopic studies revealed an infiltration of the jejunal wall by abnormal lymphocytes. The cecal and ileal walls were infiltrated by leukocytes. Blood vessels were invaded by giant cells and large, unseptated, right-angle branching hyphea. CONCLUSIONS: These findings were considered typical of invasive mucormycosis of the cecum and the terminal ileum.     

The digestibility and chemical composition of plant parts in Italian and perennial ryegrass during primary growth

Italian ryegrass (cv. S22) and perennial ryegrass (cv. S24) were sampled duringprimary growth at head emergence, pollen shedding and seed shedding in each of 2 years. Each sample was separated into approximately 19 plant parts and for each part the true dry matter digestibility, digestibility of cell wall and percentages of cell content, nitrogen, water-soluble carbohydrate and lignin were determined. Trends reported in the literature, based on a smaller number of plant parts, were generally confirmed, but were shown to conceal appreciable variation. Thus, while, on average, stem declined in digestibility faster than leaf sheath, the upper sheaths declined in digestibility faster than the lower internodes and nodes; similarly, the proportion of cell content declined at a rather similar rate to digestibility in leaf blade and much less than digestibility in stem but the position was reversed between pollen shedding and seed shedding in the case of dead leaf blade and internodes. While the N content of the inflorescence as a whole did not decline greatly with advancing maturity, the N content of the rachis was nearly halved. The upper part of the crop was more digestible than the lower part at head emergence, but not at seed shedding. Italian ryegrass had a higher proportion of cell content than perennial ryegrass in all types of plant part. The digestibility of cell wall declined with advancing maturity in all the plant parts examined. The lower portions of internodes had a higher proportion of cell content than the upper portions. There were gradients from top to bottom of the plant, e.g. percentage N declined and percentage water-soluble carbohydrate increased from top to bottom.     

An approach for preventing the indexing of hijacked journal articles in scientific databases

Hijacked journals are cloned websites that resemble the homepages of legitimate journals, whose aim is to collect processing and publication fees from unwary authors. There is a growing recognition that the recent proliferation of these scam sites poses a threat to the integrity of the scientific process. This study presents an approach intended to prevent the indexing of papers published by hijacked journals in scientific databases by using classification algorithms. We will provide an overview of the problem, define key features of hijacked journals, and present a decision tree that can be used to detect hijacked publications.     

Goals in conflict: semantic foundations of goals in agent programming

This paper addresses the notion of (declarative) goals as used in agent programming. Goals describe desirable states, and semantics of these goals in an agent programming context can be defined in various ways. We focus in this paper on the representation of conflicting goals. In particular, we define two semantics for goals, one for unconditional goals and one for conditional goals. The first is based on propositional logic, and the latter is based on default logic. We establish relations between and properties of these semantics. This title was inspired by the title of the PhD thesis of Harrenstein: Logic in conflict: logical explorations in strategic equilibrium [25].