Control of coal gasifier during variations in the calorific value of coal is quite complex because of its non linearity and interactions among control parameters. Advanced control strategies are being employed to meet the stringent performance requirements of the gasifier. In this paper, the authors have proposed the classical Chien, Hrones and Reswick (CHR) tuning method for adjusting cPI controller parameters and demonstrated that this method is still giving better results. With these parameters the performance of fluidized bed coal gasifier is examined under pressure disturbance and coal quality variations. It is evident that the results obtained are superior to the existing methods found in literature.

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This paper examines the physiochemical properties of phosphoric acid treated biochar for improvement of urea fertilizer impregnation process. The biochar was heated with phosphoric acid (H3PO4) of 1.5 M (TB1) and 1 M (TB2) concentrations at 80 and 90°C temperature respectively. The treated biochar then were impregnated with 2 wt. % of dissolved urea fertilizer while continuously stirred until the mixture recrystallize to form solid urea impregnated biochar fertilizer (TB1-U and TB2-U). TB1 revealed highest composition of C (66.36%), H (6.53%) and N (1.65%) compared to TB2 composition of C (61.84%), H (4.60%) and N (1.06%). FT-IR results indicated the presence of C-O stretch functional group at 1200 cm^(-1) to 900cm^(-1) wavelength and the presence of aromatic ring (C=O) stretching vibration at 1590cm^(-1)-1550cm-1 wavelength revealed chemical reaction occurred due to phosphoric acid treatment. The microporosity results display more micropores formation on the sample surfaces, thus provide higher surface area possible for urea molecule to be impregnated. SEM-EDX exposed qualitatively and quantitatively the presence of 43% N on TB1-U surfaces compared with slightly lower at 42wt% of N on TB2-U surface evidenced the effectiveness of phosphoric acid treatment on enhancement of the biochar specific surface area to be impregnated with urea for nutrient retained.

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The temperature and salinity influence on rheology of aqueous diutan gum solution at the temperatures of 20°C, 40°C and 60°C were investigated. It was used a solution of diutan gum (4300 ppm) in deionized water and a solution of diutan gum (4300 ppm) in deionized water with 40000 ppm of NaCl. Steady shear, creep-recovery and oscillation tests were performed. Aqueous diutan gum solutions showed a pseudoplastic and viscoelastic behavior. The viscosity of aqueous diutan gum solution changes very litle in the presence of NaCl. With the salt addition, at 600C, the viscous modulus keep higher than the elastic modulus in the frequency range investigated. In the others cases, for angular velocities greater than an specific value, the elastic modulus keep higher than viscous modulus indicating a gel behavior of diutan aqueous solutions. The Cox-Merz rule is better applicable in the case of diutan gum solution (4300 ppm) at higher temperature.

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The uniform distribution of mineral and humic substances throughout the volume of granules in the preparation of organo-mineral fertilizers occurs in the layer-shaped mechanism of granulation. To achieve this goal, the introduction of a multicomponent heterogeneous liquid phase into a fluidized bed medium using a mechanical dispersant. The introduction of a liquid phase in the middle of a fluidized bed with the use of a mechanical disperser of conical type with a perforated surface can significantly increase the volume of the irrigation zone with the simultaneous movement of moist granules from the bowl of the dispersant outside, which eliminates the risk of formation of agglomerates and intensifies the renewal of the contact surface phases in the irrigation zone. The proposed mathematical model adequately describes the process of granulation with the use of a mechanical disperser located inside a layer of a granular material in the application of a pulsating mode of fluidization, which significantly intensifies the diffusion-controlled process in the presence of phase transitions.

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The development in power electronic technology has created a major awareness regarding power quality in power distribution system. The paper presents various control strategies of Dynamic Voltage Restorer (DVR) for Power Quality improvement in Distribution system. Paper mainly focuses on impact and mitigation of power quality issues like voltage sag/swell in power distribution system with sensitive loads. The power quality issue voltage sag or voltage swell is mitigated by injecting compensating signals using custom power device DVR. DVR is controlled using different control strategies like ABC algorithm, unit-vector theory and SRF theory in this paper. Simulation analysis is carried out for DVR in distribution system with voltage quality issues with different control strategies showing out source voltage with voltage quality problem (sag/swell), compensating signals from DVR and load voltage. Simulation analysis is carried out using MATLAB/SIMULINK software.

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In the present paper, we introduce a methodology for movement inception detection based on superficial Electromyography Signals (sEMG). Consequently, a mathematical model using feature extraction and feature flow is proposed, selected features are Mean Absolute Value (MAV), Root Mean Square (RMS), and Entropy (H). The first two are chosen due to the low computational cost, and the last one is chosen due to its outstanding behavior to recognize movements. Moreover, an experimental assessment is carried out using a wearable device so-called Myo Armband bracelet, during experiments three subjects execute grasp (close hand) and release (open hand) movements. Finally, experimental results show that entropy and entropy flow are suitable for detecting movement inception and for further classification of movement, and our methodology allows detecting movement inception in $245.9$ms, out of laboratory conditions.

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A typical demand balance based improvement design of Water Supply System in a developing Community is presented. Taking data from a characteristic Campus Community in Nsukka, South East Nigeria, hydraulic calculation of water networks was implemented using selected systems of equations that were best suited for the exercise. The EPANET 2 software was explored in performing required pressure, velocity and flow analysis peculiar to the studied Campus. The Water demand of 3, 645,000 liters per day at the time of Campus inception in 1960 had risen to a demand of nearly six million liters per day at present, due to expansion in all spheres of the Campus. The new design was based on present and future Water demands in the Area which were estimated as 5,901,834 liters/day and 55,764,618 liters/day respectively. The result shows that Water supply for all Campus needs can be improved by 60% under the assumption of per capita liter demand of 150 in the improved design.

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This paper presents a comparative analysis between two different stacked rectangular dielectric resonator antenna design structures. Two separate stacked Structure has been designed using sapphire and thermoset microwave material TMM13i respectively. Both the antenna design structures are aperture coupled. Due to advantage of aperture coupled feed mechanism such as good isolation between antennas and feed networks it has been employed. The simulation results obtained indicates that sapphire stacked rectangular dielectric resonator antenna design has better performance as compared to the thermoset microwave material TMM13i stacked rectangular dielectric resonator antenna design. The sapphire stacked antenna design exhibits two frequency bands from 7.41GHz to 8.21 GHz and 9.11GHz to 12.65GHz whereas TMM13i stacked antenna shows only one frequency band from 8.62 GHz to 10. 6GHz.The radiation efficiency of sapphire stacked antenna is far more superior than TMM13i stacked antenna. Hence Sapphire stacked rectangular dielectric resonator antenna has proven to be the good material for designing antennas in future and thus can be used for C-band applications as well as X-Band applications.

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Applications to be solved in parallel fashion use distributed environments. Generally, these kinds of applications are large computational projects of high complexity. The distributed environment is a massive pool of heterogeneous resources which could be utilized by the applications. Grid computing environment is one such environment that aggregates networks, computers, servers, applications, programs and the users. The co-ordination of resources is the mandatory aspect of distributed computing environment and this is achieved by efficient scheduling. An effective scheduling is very significant as it encounters high performances. A high quality scheduling is meant for its low cost, earlier completion, accurate results; and obviously that might be the key expectation of the clients too. These can be met only when resources are properly utilized by the applications. Parallel applications are illustrated mathematically as Directed Acyclic Graphs (DAGs), which help us to understand the dependencies and data mobility in the real applications. In this article, we present a scheduling algorithm that motivates quick and quality schedules, which in turn encourages reduction of makespan time, increases speed up and best rate of result recurrences. The algorithm called PD-SECT (Priority on Dependency and Start, Execution, Communication Time) is based on list heuristics. The algorithm accomplishes the stages of (i) task selection, (ii) resource selection, (iii) mapping the chosen task and resource. The priority in selecting the tasks and resources is based on the following criteria, (i) task selection is based on population of inter dependent tasks; (ii) resource selection is based on resource availability with respect to the start and execution time. The proposed algorithm does not encourage insertion policy as the tasks are encouraged to pack consecutively without idle slots. On comparisons with algorithms of its kind, this algorithm arrived at best results when scaled from smaller to bigger task graphs. The algorithms are implemented in GridSim simulator, which gives a feel of real time environment.

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We present in this paper a new symmetrical metaheuristic speech encryption for secure communication. Our approach consists of shuffling the samples of a speech signal using a metaheuristic generated key before transmission. The need for real-time encryption systems for audio communication is increasing due to the widespread of real-time voice applications, such as voice over IP. To minimize any delay, the speech signal is segmented into frames that are encrypted on the spot and transmitted to the receiver. Once received at the receiver side, the speech frame is decrypted and concatenated with the previous speech frames. The objective and subjective measures show that our technique outperforms the existing block encryption algorithms in terms of execution time and security performance.

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In knowledge discovery and data mining, clustering is an aggressive concept to explore different attributes with different relations, because each data type has its own and unique challenge to achieve relative data based on partitioning of homogeneous data. In knowledge discovery categorical data clustering is an essential and challenging task because of special characteristics. So to arrange attributes in systematic manner for uncertain categorical data indexing approach is required. In this paper we propose and introduce A Novel Fuzzy based Partitioned Genetic Algorithm (NFPGA) for uncertain categorical data. This novel approach consists two phases to explore and process categorical data. In first stage partition data set with maximum number of clusters then combine all the clusters generated in first phase. This procedure repeated until number of clusters equal to pre-defined clusters present in data set. This proposed approach i.e. NFPGA is implemented on synthetic data sets which are available UCI repository, novel fitness function; cross-over and mutation operations are evaluated on categorical data based on parallel partitioning procedure. Performance of proposed approach has been crossover with different existing clustering related approaches with objective functionalities and similarity index measures, from this proposed approach gives better and excellence performance.

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Abstract:

In the current digital planet, the size of the data centre has been increasing significantly but it comes at the cost of some major issues, especially a huge consumption of power. Cloud computing has been an emerging paradigm which provides services propagating across the digital world as well as it offers advanced virtual computing resources across internet with least management hazards. However, the whole computing resources face the main pitfall which is extremely energy consumption aspect which usually requires tremendously high energy consumption especially in case of unutilized resources. Hence the output comes with a big impact on the entire environment. In this paper, we target on the comprehensively optimized way of arrangements of virtual machines to balance the resource management across the cloud. In the digital age, there are countless techniques and several algorithms are proposed to reduce the consumption issue especially power and energy in the cloud. Few major techniques like dynamic voltage and frequency scaling DVFS, virtual machine migration and virtual machine consolidation are the key solutions to address this issue.

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The aim of this work is to create an experimental-numerical technique for elastic parameters identification of laminated polymer composites using experimental modal analysis. The object of this research is laminated carbon fiber reinforced composite based on an equally strong carbon fabric and epoxy binder. Experimental determination of natural frequencies and corresponding vibration modes was performed using 3D scanning laser vibrometry. The finite element calculation and quasi-random search optimization technique can be effectively used to solve the identification problem. The evaluation by independent experiments showed that the error of the natural frequencies, determined from the obtained elasticity characteristics, lies within 5%. The described technique can be recommended for determining of elasticity parameters necessary for calculating the modal characteristics of structure elements made from laminated carbon fiber.

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The use of steganography as an alternative for cryptography in the field of data security is growing. One of the main issues in steganography is the search for a strong secret key and an efficient embedding algorithm hiding confidential messages into the chosen carrier multimedia. This paper presents a new method for generating the secret embedding key employing the traditional way of representing the dates. Hash tables were generated in three levels using the date components, and are utilized for embedding the secret message into carrier images using Least Significant Bit (LSB) hiding process. The three level hashing tables would result in increased difficulty for attackers providing data security strength. Obtained results of the conducted tests manifested even distribution of the histogram and comparable Peak Signal to Noise Ratio (PSNR) with a traditional LSB scheme.

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Rising medical expenses and increased life expectation impose big issues for proper health care and monitoring. Wireless Body Bio-Sensor Networks (WBBSNs), a set of tiny bio-sensor nodes attached within, on and/or around the patient body, were placed to meet this requirement. Due to patient body postural change, ultra short range radio links and random RF attenuation lead to on-body topology disconnections occur, which results more energy consumption and network lifetime is reduced. To address these issues we proposed, an IMproved Reliable, Energy Aware and Stable Topology (IM-REAST) protocol to maximize network stability period and minimize energy consumed by bio-sensor nodes on-body topology for WBBSNs. This algorithm applies the mixed mode communication between bio-senor nodes and the sink, which employs a new forwarder function for selection of forwarder node. This mixed mode communication reduces the energy consumption of the network and maximizes the network lifetime. This paper provides a comparison of three of the routing protocols, SIMPLE, ATTEMPT and proposed. The comparison is performed at the 2.4 GHz frequency (IEEE 802.15.4) on- body bio-sensor set-up. The proposed protocol performances are compared in terms of stability of network, residual energy, packet received at sink and path loss and simulation results shows that performance of overall network is improved by 25% as compared with SIMPLE and ATTEMPT protocols.

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In wireless communications, accessing the world wide information by the end user is being a challenge due to seamless mobility among different networks. In order to provide wireless access for the end user moving from one network to another network handover between the networks is very much essential. Bandwidth is the one of most important metric used for analyzing the handover. In this paper, the bandwidth based probability of handover (PHO) algorithm has been implemented for Beyond Fourth Generation (B4G) heterogeneous wireless networks. The probability of handover relies on the traffic load, bandwidth and threshold. Probability of handover analysis has been done for different configurations such as the variation of probability of handover with respect to traffic load, threshold and bandwidth. It is noticed from the results that with increase in threshold, the probability of handover is reduced for constant traffic load. It is also observed that even though network traffic load increases, the probability of handover does not vary much for the equal bandwidth network configuration.

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In the article, from the standpoint of an integrated systems approach, a theoretical rationale is presented for the choice of an efficient method for the removal of fluorine from wastewater from industrial enterprises engaged in the processing of limestone.

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According to the World Health Organization (WHO), road accidents are regarded as one of the leading causes of death. The trend of a road accident can change in future as it is hard to predict the rate at which road accidents are taking place. The road accident leads to an unacceptable loss in terms of property, health and other economic factors. There are instances where road accidents occurred more frequently at a specific location. Some of the road accident features influence road accident to occur frequently. So, it is essential to identify the correlation in various attributes of road accident for predicting road accident. Data mining techniques are widely used to find the correlation in various attributes of the large database. A data mining approach was proposed to characterize road accident locations. In this approach, the Apriori algorithm was applied to characterize locations by generating rules. The Apriori algorithm has high space and time complexity problem and it is also costlier process owing to a large database. In this paper, Frequent Pattern-growth (FP-growth) is introduced for road accident prediction. In FP-growth, the larger feature space is condensed into smaller sub-spaces so that the costly repeated scans are avoided. Then the attributes with high confident values are trained by a decision tree classifier called as J48. It trains and classifies the data as critical and non-critical accident type. Hence by using FP-growth space and time complexity of association rule mining based road accident prediction is reduced and its accuracy is improved by using J48 classifier.

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Water-jet cutting machine is commonly used in industry. This kind of machine can be operated in many types of design and material of the product. Generally, there are two types of water-jet machining which is Water-jet Machining (WJM) and Abrasive Water-jet Machining (AWJM). However, several problems occurs to manage the workpiece during the cutting process and the movement of the nozzle. Moreover, the misalignment of the workpiece during the cutting process also one of the issues. The objective of this study is to develop and optimize water-jet clamping. As a conclusion, an improved clamping design for water-jet is proposed to fulfill industry requirements.

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The purpose of the study is to increase the use of the resource of brake pads of motor vehicles through the development of new science-based technical solutions. Research methods - experimental studies based on the brake pads of a production car with the introduction of a conductive layer into the friction lining with the output of the light and sound alarm to the driver. The article presents the results of experimental studies on the process of limiting wear of the friction linings of brake pads. During the development of practical recommendations for the technical diagnosis of vehicles, it was confirmed that for monitoring the technical condition of vehicles, it was proposed to use a device to inform the driver about the wear of the brake lining, the use of which increases the utilization of the brake lining resource by up to 98%. The use of this device in the future will allow to track the dynamics of changes in the thickness of the brake lining, which will facilitate the control of wear and ensure timely repair of the brake system with low costs of materials and tools.

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This research work is designed to estimate the temperature variations in selected districts of Punjab, Pakistan. The estimation is performed using estimation semi-log model and secondary data based on time series data (1981-2013) of maximum and minimum temperature of selected districts of Punjab is used as input data for semi-log model. The secondary data has been collected from district wise Punjab development statistics. Keeping in view the availability of data district Bahawalpur, Bahawalnagar, Faisalabad, Multan, and Rawalpindi/Islamabad have been selected for estimation of maximum and minimum temperature.

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The developed mathematical model takes into account the hydrodynamics of the fluidized bed, the contact of droplets with particles and their adhesion to the surface, as well as the kinetics of drying the solution on the surface of the particles. When creating a model, the process of dewatering and granulation in a fluidized bed is considered as a heterogeneous three-phase process, during which interact with three separate phases: particles - granulation centers, the starting material - ammonium sulfate in the form of droplets and heat carrier - air. To get the dynamic characteristics of the developed system, the Simulink library of the Matlab application package is used. With the help of built-in library elements, a scheme of differential equations describing the model of the control object is obtained.

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