RISCBOT: A WWW-Enabled Mobile Surveillance and Identification Robot

This article describes RISCBOT (RISCBOT name has been derived from RISC lab and ‘bot’ of robot, a modular 802.11 b-enabled mobile autonomous robot built at the RISC lab of the University of Bridgeport. RISCBOT localizes itself and successfully fulfills www – enabled online user requests and navigates to various rooms, employing a visual recognition algorithm. This article describes the mechanical design, hardware and software algorithms of the robot, and the web-based interface for communicating with the robot. ^⋆RISC lab: Interdisciplinary Robotics, Intelligent Sensing and Control laboratory at the University of Bridgeport.     

Rigorous Full-Wave Analysis of Rectangular Microstrip Patch Antenna on Suspended and Composite Substrates

In this paper, Galerkin’s method in the Fourier transform domain is applied to the determination of the resonant frequencies and half-power bandwidth of rectangular microstrip patch on composite and suspended substrates. Using Galerkin’s method in solving the integral equation numerically, the complex resonant frequency of the microstrip antenna on suspended and composite substrates is studied with sinusoidal functions as basis functions, which show fast numerical convergence. The validity of the solution is tested by comparison of the computed results with experimental data. Finally, numerical results for the effects of suspended and composite substrates on the resonant frequency and half-power bandwidth are also presented.     

Design of a commercial solar-powered greenhouse

A completely solar-powered greenhouse complex has been designed for climate controlled food production in hot, humid environments. The concept uses passive design features to provide irrigation water from saline water sources. This paper discusses the overall system concept and the solar still subsystem which has been designed to provide a continuous fresh water supply. While incorporating many innovative features, the use of proven technologies and passive design results in a system that should compete economically with current, more traditional designs.     

Study on QoS Management for Video Streaming in Vehicular Ad Hoc Network (VANET)

Wireless Personal Communications - Vehicular Ad Hoc Network (VANET) is a particular type of MANET providing various wireless communications such as infrastructure communications and inter-vehicle...     

Construction of a stable vehicular ad hoc network based on hybrid genetic algorithm

Telecommunication Systems - In vehicular ad hoc networks, the vehicle speed can exceed 120 kmph. Therefore, any node can enter or leave the network within a very short time. This mobility adversely...     

Enhancing VANETs Broadcasting Performance with Mobility Prediction for Smart Road

Wireless Personal Communications - In the last decade, daily lifestyles have been invaded by mobile networks which added a huge exchange of information. This exchange among vehicular nodes as a...     

Improving solidification pattern of ESR ingots combined with energy savings

Most of the metallurgical effects resulting from electroslag remelting of metal may be divided into two groups, namely, the effects due to the slag/metal reactions taking place and the effects due to the special solidification conditions characteristic of this process. Solidification of ESR ingots takes place progressively as heat is removed from the liquid metal pool via the mold walls. By careful matching of the melting rate with the freezing rate, the desired shallow metal pool is attained, leading to the well known directional solidification pattern with consequent improvement in properties of the steel. The choice of power parameters is limited by a compromise between the need for a high melting rate for economic reasons (costs) which may tend to give a rather deep metal pool and the need for a shallow metal pool to obtain optimum metallurgical properties. In this process only a relatively small amount of the total energy input is actually utilized to melt down the metal. The major part of the energy is lost from the slag and metal pool to the water cooled mold. In this paper the results of numerical and experimental investigations are presented, setting out a simple method of saving energy and controlling the solidification pattern of the ingot. This method involves the addition of solid particles to the melt to utilize the surplus energy evolved in the central area of the slag bath.     

Raffination von Stahl mit einer Calcium/Magnesium-Legierung

Die Raffination eines unlegierten, aluminiumberuhigten Baustahls mit Ca/Mg, speziell der Verbindung CaMg₂, wurde theoretisch unter Verwendung eines thermochemischen Datenbanksystems (Therdas Datenbanksystem²)) und experimenteller Laborschmelzen untersucht. Die theoretisch aufgezeigten Entschwefelungs- und Desoxidationseigenschaften wurden durch die Schmelzversuche bestätigt, bei denen Gehalte von 15 ppm Sauerstoff und 20 ppm Schwefel eingestellt werden konnten. Die Reaktionsprodukte und die möglichen Einschlußmodifikationen konnten durch die Berechnung weitestgehend vorhergesagt werden. Schon bei CaMg₂-Zugaben von 0,01 % werden die Tonerdeeinschlüsse instabil und durch das Behandlungsmittel zu 12CaO · 7Al₂O₃ bzw. MgO · Al₂O₃ umgesetzt. Eine geringfügige Erhöhung der Raffinationsmittelangebote auf 0,03 % reicht in der Regel aus, damit auch diese Spinelle und Aluminate ihre Stabilität verlieren. Die für die Anisotropie der Zähigkeitswerte im Ausgangswerkstoff verantwortlichen langgestreckten, separaten Mangansulfide werden bereits durch geringe Mengen des Behandlungsmittels (≤ 0,1%) beseitigt und liegen nach der Behandlung nur noch vereinzelt in Form kleiner, runder bzw. teilweise elliptisch verformter Einschlüsse der Größenordnung 1–3 μm vor. Andere, nach der Behandlung im Stahl verbleibende Einschlüsse, wie globulare Calcium-Aluminate, eckige Magnesia-Tonerde-Spinelle und besonders häufig meist runde Formen von Kombinationen dieser Komponenten liegen im Bereich von 1–4 μm vor. Der hohe Reinheitsgrad des Werkstoffes führt zu einer Verminderung der Anisotropie der mechanischen Eigenschaften. Da die geringe Löslichkeit von Calcium und Magnesium im flüssigen Stahl keinen Aufbau eines Reaktionsmittelvorrates in der Schmelze erlaubt, sollte die Raffinationsmittelzugabe kontinuierlich erfolgen, wozu sich verfahrenstechnisch Injektionsanlagen und Drahtspulsysteme anbieten.     

Quantitative Assessment for Piles Productivity Factors

The management process of any construction operation usually can be defined as a chain of decisions. A decision-maker can bid, plan, and organize the bored pile projects based on an accurate estimate of productivity. To estimate productivity efficiently, piling process qualitative and quantitative factors have to be considered. This paper focuses on assessing the effect of subjective factors on bored pile construction productivity. A productivity index (PI) model is developed to represent this subjective effect in refining productivity assessment using simulation and deterministic techniques. The analytic hierarchy process and fuzzy logic are used to develop the proposed PI model that relies on the actual performance of 10 main piling process subjective factors. Subjective data were collected from bored pile (drilled shaft) contractors considering these subjective factors. The developed PI model implementation to piling process resulted in PI=0.7. This value has been validated using simulation model outputs.