An efficient hybrid algorithm based on modified imperialist competitive algorithm and K-means for data clustering

Clustering techniques have received attention in many fields of study such as engineering, medicine, biology and data mining. The aim of clustering is to collect data points. The K-means algorithm is one of the most common techniques used for clustering. However, the results of K-means depend on the initial state and converge to local optima. In order to overcome local optima obstacles, a lot of studies have been done in clustering. This paper presents an efficient hybrid evolutionary optimization algorithm based on combining Modify Imperialist Competitive Algorithm (MICA) and K-means (K), which is called K-MICA, for optimum clustering N objects into K clusters. The new Hybrid K-ICA algorithm is tested on several data sets and its performance is compared with those of MICA, ACO, PSO, Simulated Annealing (SA), Genetic Algorithm (GA), Tabu Search (TS), Honey Bee Mating Optimization (HBMO) and K-means. The simulation results show that the proposed evolutionary optimization algorithm is robust and suitable for handling data clustering.     

Environmental and Safety Aspects of Using Tritium in Fusion

Today most current fusion research and development activity is based on the expectation that the D–T reaction will be used for the first generation of fusion reactors. This mixture is the premier candidate for a fusion fuel on account of its outstanding energy gain. Fusion reactors will produce neither the problematic emissions now experienced from fossil-fuel-burning power plants nor the long-lived fission products and transuranic elements resulting from fission reactors. Even though, tritium is a radioactive isotope of hydrogen with 12.32 years half-life that exposes beta radiation. Although its specific activity is relatively weak but because of its gaseous state, it can leak easily from its container and contaminate its surrounding. In order to improving safety and reliability of fusion reactors, research groups jointly investigate radiation hazards resulting from the release of tritium and activation products during normal operations as well as accidental conditions. In this paper, some of the most significant safety and environmental aspects of tritium is briefly discussed.     

Multi-Scaled Modeling the Mechanical Properties of Tubular Composites Reinforced with Innovated 3D Weft Knitted Spacer Fabrics

Textile composites of 3D integrated spacer configurations have been recently focused by several researchers all over the world. In the present study, newly-designed tubular composites reinforced with 3D spacer weft knitted fabrics were considered and the effects of their structural parameters on some applicable mechanical properties were investigated. For this purpose, two different samples of 3D spacer weft knitted textile types in tubular form were produced on an electronic flat knitting machine, using glass/nylon hybrid yarns. Thermoset tubular-shaped composite parts were manufactured via vacuum infusion molding process using epoxy resin. The mechanical properties of the produced knitted composites in term of external static and internal hydrostatic pressures were evaluated. Resistance of the produced composites against the external static and internal hydrostatic pressures was numerically simulated using multi-scale modeling method. The finding revealed that there is acceptable correlation between experimental and theoretical results.     

A dynamic data dissemination mechanism for Cassandra NoSQL data store

The Journal of Supercomputing - Cassandra as a type of NoSQL databases has been put forward so as to surmount the hurdles of traditional relational databases in the scope of big data as well as...     

Integral representation and bounds for Marcum Q-function

A new expression for the Marcum Q-function involving an integral over a fixed interval is given. Tight upper and lower bounds are then derived and applied to the performance evaluation of noncoherent and differentially coherent detection of digital modulation over Nakagami fading channels     

Superparamagnetic magnetite nanoparticles for cancer cells treatment via magnetic hyperthermia: effect of natural capping agent,particle size and concentration

Journal of Materials Science: Materials in Electronics - Superparamagnetic iron oxide nanoparticles (SPMNPs) continue to emerge as one of the most potential candidates in biomedical applications....     

Photoluminescence and UV photosensitivity of few-layered MoS2 nanosheets synthesized under different hydrothermal growth times

Journal of Materials Science - MoS2 flower-like microspheres composed of 2D nanosheets were prepared using the simple and cost-effective method of hydrothermal. The effects of hydrothermal process...     

A Model of Mechanotransduction in Polyvinyl Alcohol-Based Composite Hydrogels for Regulating Musculoskeletal Differentiation

In regenerative medicine, extracellular matrix (ECM)-inspired materials are currently being explored to imitate mechanotransduction pathways and control cell fate. In musculoskeletal tissue regeneration, enhancing mechano-biological signals require biomaterials that are both biocompatible and viscoelastic and can retain water content. Herein, based on these requirements, various polyvinyl alcohol (PVA)-based composite hydrogels, reinforced by polyhydroxy butyrate (PHB) nanofibers, are proposed to differentiate equine adipose-derived stem cells for musculoskeletal regeneration. To study the role of fiber embedding in improving scaffold properties, different nanofiber assemblies, including chopped short ones with random orientation (PVA_S), single-layer (PVA_L1), and double-layer membranes (PVA_L2) are positioned into the PVA matrix. PHB reinforcements negatively affect swelling and positively enhanced phase transition temperatures and crystallinity of PVA hydrogel. According to mechanical analysis results, compositing with PHB nanofibrous layers strengthen the PVA matrix due to some restrictions on PVA chain mobility. Gene expression investigations also reveal that higher matrix stiffness after layering with two PHB membranes (PVA_L2) promotes osteogenesis, while the random addition of short-chapped fibers (PVA_S) facilitate tenogenic differentiation. As a consequence of the findings, fiber placement is crucial to the mechanical properties of composite hydrogels that ultimately control musculoskeletal differentiation signals through mechanosensing pathways.