Prickly pear sheets: a new fruit product

Dried sheets (Teen-Edin) from prickly pear (Taifi cultivar) fruits were made and the composition of the pulp and the optimum formulation sheet was analysed. The optimum formulation was obtained by adding to fruit pulp (100%), 10% sucrose, 1.1% citric acid, 0.15% sodium metabisulphite, and 0.5% olive oil (w/w). Sodium metabisulphite improved the colour and citric acid produced a similar acid taste to the traditional apricot sheets. The sheets were highly acceptable to a small panel and have potential for manufacture as a possible alternative to apricot sheets (Kamar-Eddin). The technique could also be used for preservation in many other arid parts of the world where prickly pears grow.     

Reconfigurable processing for satellite on-board automatic cloud cover assessment

Clouds have a critical role in many studies such as weather- and climate-related investigations. However, they represent a source of errors in many applications, and the presence of cloud contamination can hinder the use of satellite data. In addition, sending cloudy data to ground stations can result in an inefficient utilization of the communication bandwidth. This requires satellite on-board cloud detection capability to mask out cloudy pixels from further processing. Remote sensing satellite missions have always required smaller size, lower cost, more flexibility, and higher computational power. Reconfigurable Computers (RCs) combine the flexibility of traditional microprocessors with the power of Field Programmable Gate Arrays (FPGAs). Therefore, RCs are a promising candidate for on-board preprocessing. This paper presents the design and implementation of an RC-based real-time cloud detection system. We investigate the potential of using RCs for on-board preprocessing by prototyping the Landsat 7 ETM+ ACCA algorithm on one of the state-of-the-art reconfigurable platforms, SRC-6. It will be shown that our work provides higher detection accuracy and over one order of magnitude improvement in performance when compared to previously reported investigations.

Recognizing handwritten Arabic words using grapheme segmentation and recurrent neural networks

The Arabic alphabet is used in around 27 languages, including Arabic, Persian, Kurdish, Urdu, and Jawi. Many researchers have developed systems for recognizing cursive handwritten Arabic words, using both holistic and segmentation-based approaches. This paper introduces a system that achieves high accuracy using efficient segmentation, feature extraction, and recurrent neural network (RNN). We describe a robust rule-based segmentation algorithm that uses special feature points identified in the word skeleton to segment the cursive words into graphemes. We show that careful selection from a wide range of features extracted during and after the segmentation stage produces a feature set that significantly reduces the label error. We demonstrate that using same RNN recognition engine, the segmentation approach with efficient feature extraction gives better results than a holistic approach that extracts features from raw pixels. We evaluated this segmentation approach against an improved version of the holistic system MDLSTM that won the ICDAR 2009 Arabic handwritten word recognition competition. On the IfN/ENIT database of handwritten Arabic words, the segmentation approach reduces the average label error by 18.5 %, the sequence error by 22.3 %, and the execution time by 31 %, relative to MDLSTM. This approach also has the best published accuracies on two IfN/ENIT test sets.     

Multi-load level reactive power planning considering slow and fast VAR devices by means of particle swarm optimisation

The problem of optimal allocation of fast and slow reactive power VAR devices under different load levels is addressed. These devices are supposed to be utilised to maintain system security in normal and contingency states, where corrective and preventive controls are implemented for the contingency cases. Load shedding and fast VAR devices are used in the corrective state in order to restore the system stability very quickly, even though they are highly expensive, whereas cheap slow VAR devices can be used in the preventive state to obtain the desired security level. The main objective is to establish a trade-off between economy and security by determining the optimal combination of fast and slow controls (load shedding, new slow and fast VAR devices). To meet the desired steady-state security limits, a variety of constraints have to be considered during the investigated transition states. The overall problem is formulated as a large-scale mixed-integer nonlinear programming problem. Particle swarm optimisation as an efficient method for solving such problems is applied to solve the problem. The proposed approach has been successfully tested on the IEEE-14 as well as IEEE-57 bus systems.     

Effect of temperature and cooling regime on mechanical properties of high‐strength low‐alloy steel

This paper presents results from experimental studies on the effect of temperature on mechanical properties of high‐strength low‐alloy ASTM A572 steel commonly used in structural members in bridges. A set of high‐temperature tensile strength tests and post‐temperature exposed residual strength tests is carried out on ASTM A572 steel coupons in 20–1000 °C temperature range. The residual strength tests on high‐temperature exposed steel coupons are carried out after subjecting the coupons to two methods of cooling, namely, air cooling and water quenching. Results from these tests indicate that temperature‐dependent strength and stiffness degradation in A572 steel follow the same trend as that of carbon steel but with some variations. A572 steel recovers almost 100% of its room temperature yield strength when heated to temperature up to 600 °C, regardless of the method of cooling, while the extent of strength degradation in coupons subjected to heating beyond 600 °C is dependent on heated temperature and method of cooling. Data generated in these tests are utilized to generate high‐temperature stress–strain and residual stress–strain response of A572 steel. These results are also utilized to propose temperature‐dependent strength, elastic modules, and residual strength reduction factors of A572 steel, which can be used in evaluating residual response of fire‐exposed steel structures. Copyright © 2015 John Wiley & Sons, Ltd.     

Single-Bit Comparator in Quantum-Dot Cellular Automata (QCA) Technology Using Novel QCA-XNOR Gates

To fill the continuous needs for faster processing elements with less power consumption causes large pressure on the complementary metal oxide semiconductor (CMOS) technology developers. The scaling scenario is not an option nowadays and other technologies need to be investigated. The quantum-dot cellular automata (QCA) technology is one of the important emerging nanotechnologies that have attracted much researchers’ attention in recent years. This technology has many interesting features, such as high speed, low power consumption, and small size. These features make it an appropriate alternative to the CMOS technique. This paper suggests three novel structures of XNOR gates in the QCA technology. The presented structures do not follow the conventional approaches to the logic gates design but depend on the inherent capabilities of the new technology. The proposed structures are used as the main building blocks for a single-bit comparator. The resulted circuits are simulated for the verification purpose and then compared with existing counterparts in the literature. The comparison results are encouraging to append the proposed structures to the library of QCA gates.     

Characteristics of low‐fat beefburgers as influenced by various types of wheat fibres

Hydrated wheat fibres (bran and white and red beeswings) were added at three levels (50, 100 and 150 g kg⁻¹ ) to beefburger as replacement for fat and evaluated for chemical and physical properties, energy content and sensory traits. Uncooked and cooked beefburgers formulated with wheat fibres had higher (P⩽0.05) moisture, protein and carbohydrate contents and lower (P⩽0.05) fat contents than that of the control. However, ash content was increased (P>0.05) by the addition of wheat fibres. The cholesterol content of uncooked and cooked beefburgers decreased as level of wheat fibres increased or fat content decreased. The addition of wheat fibres reduced the cholesterol content from 6 to 45% for uncooked and cooked beefburgers. The energy content of uncooked and cooked beefburgers was lower (P ⩽0.05) than that of control by between and 6 and 41%. The cooking yield and reduction in diameter of beefburgers were significantly (P⩽0.05) improved by the addition of wheat fibres. The addition of red and white beeswings showed an improvement in the texture trait. Colour traits, tenderness, juiciness, connective tissue amount, beef flavour intensity and overall palatability were not affected by the addition of wheat fibres to beefburgers. Hydrated wheat fibres can be used successfully as a fat substitute in ground meat products. © 1999 Society of Chemical Industry     

A new formulation for FACTS allocation for security enhancement against voltage collapse

This paper proposes a new formulation for reactive power (VAr) planning problem including the allocation of flexible ac transmission systems (FACTS) devices. A new feature of the formulation lies in the treatment of security issues. Different from existing formulations, we directly take into account the expected cost for voltage collapse and corrective controls, where the control effects by the devices to be installed are evaluated together with the other controls such as load shedding in contingencies to compute an optimal VAr planning. The inclusion of load shedding into the formulation guarantees the feasibility of the problem. The optimal allocation by the proposed method implies that the investment is optimized, taking into account its effects on security in terms of the cost for power system operation under possible events occurring probabilistically. The problem is formulated as a mixed integer nonlinear programming problem of a large dimension. The Benders decomposition technique is tested where the original problem is decomposed into multiple subproblems. The numerical examinations are carried out using AEP-14 bus system to demonstrate the effectiveness of the proposed method.     

On the intricacy of imaging with incoherently-scattered radiation

Imaging with incoherently-scattered radiation has been promoted for many years as an alternative to the conventional process of radiography and computed tomography with transmitted radiation. Scatter imaging resembles natural vision, needs only frontal access to the object, provides point-wise differential information and can determine directly the density of an object without inference from the attenuation coefficient. Nevertheless, in spite of many decades of development effort, since the technique was first introduced by Lale [P.G. Lale, Phys. Med. Biol. 4 (1959) 159], the scatter imaging modality has not prevailed. This paper tracks the development of this imaging modality, presents some recent advances and outlines the remaining challenges.     

Cooling process of water in a horizontal circular enclosure subjected to non-uniform boundary conditions

This paper investigates the cooling process of water in a circular enclosure subjected to non-uniform boundary conditions. Half of the enclosure boundary is maintained at a constant temperature, while the other half is well insulated. The enclosure is cooled from its top, bottom, or left side. The problem is solved numerically using the finite element method. The examined Rayleigh numbers are 1 × 10⁵, 1 × 10⁶, and 1 × 10⁷, and the effect of maximum density at 4 °C is considered. The results indicate that the natural convection flow plays a significant role on the cooling process of water. The effects of the cooling side and Rayleigh number on the cooling process are presented. For Ra = 1 × 10⁵, the results indicate that the bottom cooling side has the lowest cooling time, but it has the highest cooling time for Ra = 1 × 10⁷. For Ra = 1 × 10⁶ and 1 × 10⁷, the left cooling shows lowest cooling time. For Ra = 1 × 10⁵, the bottom cooling case takes 52.97% less time than the top cooling case to complete the cooling process. The density inversion near 4 °C creates a unique natural convection flow, and high resolution capturing of temperature contours and natural convection flow is presented.