Статьи журнала - International Journal of Engineering and Manufacturing
Все статьи: 508
Статья научная
The mechanical properties of a friction material primarily depend on the interfacial adhesion between all the ingredients of a friction material. In this work, a new friction material is developed by combination carbon fiber (CF), polymer matrix and other ingredients. The surface of CF is chemically inert and hydrophobic in nature and does not possess good bonding property with resin. Therefore, an attempt is made to improve the bonding strength between all the ingredients of a friction material. CF surface is modified by three different surface treatment techniques to increase hydroxyl or carboxyl groups on the surface. First, surface oxidation treatment, Second nitric acid treatment and third grafting multi walled carbon nano tubes functionalized (MWCNT-F) on CF surface. CF content after surface modifications is varied in wt % and mixed with remaining ingredients. Friction composite sheets are fabricated by using hand layup method. The resulting materials are characterized by SEM, TGA and FTIR analysis. MWCNTs-F on CF surface is observed. Twelve composite sheets with varying content of CF and surface treatment method is fabricated. Sample specimens are cut from the friction composite sheets to evaluate tensile and flexural properties of friction material. The best surface treatment method and optimum ingredients are selected for the improvement of tensile and flexural properties of friction material.
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Статья научная
To Monascus spp., light is not the required factor for its growth. But Monascus spp. has the capacity to sense and respond to light. This paper investigated the effects of blue light on growth and the changes of citrinin yield in Monascus 15. Our results demonstrated blue light was a stimulating signal for citrinin formation. Under the blue light illumination, the biomass of Monascus 15 was inhibited, but the citrinin yield increased when comparing with no light culture condition. Spores statistical results revealed that the blue light also influences the development of mycelium and spore formation.
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Efficient Design of Compact 8-bit Wallace Tree Multiplier Using Reversible Logic
Статья научная
Reversible logic is now employed in low-power CMOS circuits, optical data processing, DNA calculations, biological studies, quantum circuits, and nanotechnology. When building quantum computers, for example, the use of reversible logic is unavoidable. The structure of a reversible logic circuit is far more complex than that of an irreversible logic circuit. The multiplication operation is regarded as one of the most crucial in the ALU unit. In this study, the Wallace tree method is utilized to minimize the depth of circuits in 8x 8 reversible unsigned multiplier circuits. The proposed design is an attempt to enhance design factors including the number of gates, garbage outputs, constant inputs, and quantum cost for an 8-bit Wallace Tree multiplier using reversible logic. The Proposed design offers 27% less quantum cost compared to the existing 8-bit Wallace tree multiplier design.
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Efficient Parallel Design for Edit distance algorithm in DNA Sequence Alignment
Статья научная
The focus of Bioinformatics research is usually on two aspects—genomics and proteomics, specifically, it’s starting from nucleic acid and protein sequences, analyzing the structural and functional biological information expressed in the sequences. Biological sequence alignment is one of the common problems, the Needleman-Wunsch algorithm based on dynamic programming is the most basic algorithm, and Edit Distance(Levenshtein Distance) algorithm is also widely used in DNA sequence alignment. Nowadays, there are large amount of improvements on the Needleman-Wunsch algorithm, while few on Edit Distance algorithm, so this paper focuses on revealing the effects of parallel design on optimizing the Edit Distance algorithm, and it also compares the two algorithms’ different significances in DNA sequence alignment objectively.
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Electromagnet separator of different particles
Статья научная
In this paper we simulate and realize an electromagnetic separator excited with an alternating current. And, we will to see the factors that influence the separation. This realization is used for the separation of the ferromagnetic and non ferromagnetic particles. The aim of this application is to recover the particles of non ferrous and ferrous from mixture by attractive magnetic force with big rate of separation. Experiments’ results and simulation of this separator, finally the parameters of separation are optimized with prediction method is presented in this paper.
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Статья научная
In this paper, we have introduced the structure of resonance linear motion actuator which applied to coal mine. And we have built two-dimensional analyzing model by using finite element method. On the basis of the analysis, we have calculated the motor’s air-gap field and magnetism, and we also have studied the affection of motor which caused by permanent magnet’s size. We have studied motor’s winding current when it operates at constant amplitude, and the corresponding experiment results have verified the correctness of finite element model. We have studied the numerical value calculation of resonance linear motion actuator and calculation of its magnetism characteristic. What we have analyzed shows that the air-gap field of motor changes continuously and the magnetism is proportional to winding current. And the results can help technologists to design this kind of motor.
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Статья научная
Cloud computing is a fastest growing technology in the research and industry field.It provides the on demand resources to the customers on the rent basis. These resources are provided through the virtual machines. Resources required by the virtual machines can change dynamically. So load balancing in the cloud is more challenging task as compared to the traditional computing, where the resource requirements are not changed with time. Overall performance of the cloud system can be increased by the efficient load balancing approach. Three steps are involved in the load balancing method i.e., physical machine selection, virtual machine selection and destination physical machine selection. In the past few years a number of load balancing approaches have been proposed to increase the resource utilization and minimize the energy consumption. This paper has proposed a load balancing approach which uses the lower and upper threshold to select the physical machine (PM) for migrating the virtual machine (VM). Then place the selected VM to the PM which consumes minimum power to minimize the energy consumption. To create the cloud environment, CloudSim simulator is used which provides the interface to deal with the physical and virtual machines. To evaluate the performance, the proposed method is compared with already present load balancing approaches. Simulation result shows that proposed approach minimize the energy consumption, migrations and total simulation time.
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Статья научная
Muffler acts as noise reduction element on exhaust system. Noise from an automotive application is the major source of noise pollution. Here the transmission loss of central inlet and central outlet muffler of single expansion chamber has been compared and validated in three methods namely transfer matrix method, finite element analysis and an experimental method for this purpose an experimental setup has been built up which is based on two load method. Several researchers have worked in the area of noise attenuation on central inlet by changing the position of outlet as side outlet but no one emphasizes on offset of the central inlet and central outlet position. Thereafter the finite element analysis tool Ricardo wave 1-D and comsol multiphysics is used to evaluate transmission loss for various offset position of inlet and outlet duct of the muffler. The very purpose to improve the acoustic performance of central inlet with offset outlet pipe by measuring transmission loss of offset inlet with offset outlet with various positions by keeping same space. Finite element analysis shows that higher attenuation can be achieved by increasing offset distance of central inlet & outlet outlet towards radial direction of the expansion chamber with the variation of 0.2r, 0.4r and 0.6r. Here 'r' is radius of single expansion chamber. The result shows that high transmission loss can be achieved by increasing the offset radial distance of the inlet pipe and outlet pipe. Further higher attenuation can also be achieved in case of fixed the distance of offset inlet and outlet at 0.6r by rotating the offset outlet which is also offseted at 0.6r distance by 0o, 45o, 90o, 135o and 180o. On ward rotation from remaining 180o to 360o the behavior of wave propagation will be same what has been reflected between 0o to 180o. Transmission loss maximizes when the offset outlet is loacted at 90o. It clearly reveals that optimization can be achieved by using finite element analysis tool by using virtual protyping.
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Статья научная
The use of virtual keyboards in mobile devices such as smartphones and tablets has become an essential tool for inputting information. The sound of keystrokes has been observed in previous studies to be recorded along with ambient noises, such as those produced by uncontrolled student noise, fans, doors and windows, moving cars, and similar sources. The presence of such noises negatively affects the quality of the keystrokes signal, which in turn affects keystroke analysis. The traditional FFT-based denoising methods are vital but they are often limited by their inability to adapt to the varying characteristics of real-world audio and noises. This paper proposes an enhanced Fast Fourier Transform (FFT) with an adaptive threshold technique that reduces ambient noises. The adaptive threshold technique is developed to identify frequency bins that contain noise and set their sizes to zero or attenuate them to reduce the noise. The paper evaluates the performance of the enhanced FFT with adaptive threshold on keystrokes recorded audio and validates it through extensive experimentation. The results show that the enhanced FFT outperforms the traditional FFT in terms of speed and the amount of noise removed from the recorded audio signal, indicating a significant improvement.
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Epipolar Geometry Estimation for Wide Baseline Stereo
Статья научная
The epipolar geometry is the intrinsic projective geometry between two views, and the fundamental matrix is the algebraic representation of epipolar geometry. Recovery of epipolar geometry is a fundamental problem in computer vision. Its importance is due to the fact that it provides relationships between corresponding point in the two images. In this paper, the problem of automatic robust estimation of the epipolar geometry for wide-baseline image pair is addressed. this problem for wide-baseline image pair is difficult because the putative correspondences include a low percentage of inlier correspondences, and it could become a severe problem when the veridical data are themselves degenerate or near-degenerate. Base on our previous work, a topological clustering(TC) is proposed to apply to fundamental matrix estimating. The TC algorithm has been demonstrated to be able to effectively eliminate the mismatches and reserve the correct matches. This advantage is extremely important to speeds up the performance of the epipolar geometry estimation and avoid the degeneracy. First, a set of match clusters are generated from the initial SIFT matches using topological clustering algorithm. Then, all the valid pairs of clusters are used to generate a series of fundamental matrix estimates and the best estimate is chosen as the solution. Six famous image pairs are used to test the proposed algorithms and the comparison with the related methods has been conducted. The compared experiments emphasize the performance of the proposed CPC algorithms.
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Статья научная
The removal of hexavalent chromium [Cr(VI)] is a challenging task due to its acute toxicity even at low concentration. In the present study, a low-cost activated carbon (LAC) was prepared from desert date seed shell by chemical activation with H3PO4 and utilized for the removal of hexavalent chromium from aqueous solution. Batch experiments were conducted to investigate the influence of operating variables such as pH, contact time, adsorbent dosage, initial concentration, co-existing ions and temperature. The amount of Cr(VI) adsorbed was found to vary with solution pH and maximum adsorption was observed at a pH value of 2.0. The extent of chromium uptake (mg g-1) was found to increase with increase in initial concentration and contact time. The applicability of the four isotherm models for the present equilibrium data follows the sequence: Freundlich > Temkin > Langmuir > Dubinin-Radushkevich. The mean free energy from the Duninin-Radushkevic isotherm model hinted that the adsorption of Cr(VI) onto the adsorbent surface follows physisorption mechanism. Thermodynamic parameters related to adsorption, Gibbs free energy change (∆G°), enthalpy change (∆H°), entropy change (∆S°), were also calculated and the negative value of ∆H° indicates the exothermic nature of the adsorption process. The considerable adsorption capacity of 99.09 mg g-1 is a signifier of the suitability of the prepared adsorbent for commercial application. The findings implicated that the adsorbent can be employed in the treatment of Cr-bearing water and wastewater.
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Estimating Missing Security Vectors in NVD Database Security Reports
Статья научная
Detection and analysis of software vulnerabilities is a very important consideration. For this reason, software security vulnerabilities that have been identified for many years are listed and tried to be classified. Today, this process, performed manually by experts, takes time and is costly. Many methods have been proposed for the reporting and classification of software security vulnerabilities. Today, for this purpose, the Common Vulnerability Scoring System is officially used. The scoring system is constantly updated to cover the different security vulnerabilities included in the system, along with the changing security perception and newly developed technologies. Different versions of the scoring system are used with vulnerability reports. In order to add new versions of the published scoring system to the old vulnerability reports, all analyzes must be done manually backwards in accordance with the new security framework. This is a situation that requires a lot of resources, time and expert skill. For this reason, there are large deficiencies in the values of vulnerability scoring systems in the database. The aim of this study is to estimate missing security metrics of vulnerability reports using natural language processing and machine learning algorithms. For this purpose, a model using term frequency inverse document frequency and K-Nearest Neighbors algorithms is proposed. In addition, the obtained data was presented to the use of researchers as a new database. The results obtained are quite promising. A publicly available database was chosen as the data set that all researchers accepted as a reference. This approach facilitates the evaluation and analysis of our model. This study was performed with the largest dataset size available from this database to the best of our knowledge and is one of the limited studies on the latest version of the official scoring system published for classification of software security vulnerabilities. Due to the mentioned issues, our study is a comprehensive and original study in the field.
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Статья научная
In this paper, we consider one-parameter exponential family and obtain the Bayes and. empirical Bayes estimators of the unknown parameter based on record values under a precaution asymmetry entropy loss function. The admissibility and inadmissibility of a class of inverse linear estimators of are studied based on upper records.
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Estimation of One-parameter Exponential Family Under Entropy Loss Function Based on Record Values
Статья научная
In this paper, we consider one-parameter exponential family and obtain the minimum variance unbiased estimator , Bayes and empirical Bayes estimators of the unknown parameter based on record values under entropy loss function. The admissibility and inadmissibility of a class of inverse linear estimators are also discussed based on upper records.
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Experimental Study of Airlift Pump Performance with S-Shaped Riser Tube Bend
Статья научная
Airlift pump is a type of deep well pumps. Sometimes, it is used for removing water from mines or pumping slurry of sand and water or other solutions. The performance of airlift pump is affected by two sets of parameters; the geometrical and operational parameters. The geometrical parameters include pipe diameter, pump height, design of air injection system, and entrance geometry of the lifting pipe; while the operational parameters involve submergence ratio, conditions of injected air, and nature of lifted phase. Conventionally, airlift pump with bent riser tube is less efficient than that with vertically straight riser tube. However, in real life situations, the use of local riser tube bend or flexible riser tubes is considerably unavoidable. This work investigates experimentally the effects of local bends of the riser tube on the airlift pump performance. A series of experiments on a model airlift pump with three different riser tube configurations, based on the vertical position of local bends, were carried out. The local bends are in the form of an S-shaped like duct. The results showed that setting local bends of the riser tube near the air injection zone improves the airlift pump performance. However, improvement obtained in airlift pump performance is being negligible and, thus, the position of local bend of riser tube does not contribute to improvements in the performance of airlift pump.
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Exploratory Study on Hyperledger Fabric Framework: Food Supply Chain as a Case Study
Статья научная
The wide use of supply chain management systems in various business sectors encouraged researchers and those who were concerned to explore and employ efficient technologies to improve such systems. The integration of blockchain into supply chains has proved its effectiveness at increasing the customer’s trust level, as well as many other features, such as traceability, immutability, provenance awareness, etc. Moreover, the use of private permissioned blockchain networks, for instance Hyperledger Fabric (HLF), not only leverages the level of confidence, but also increases the speed of transaction execution. In this paper, an exploratory detailed study on Hyperledger Fabric framework is conducted. The study focused on the HLF network design, the consensus algorithms used in HLF, the HLF smart contracts and the transaction flow stages. Moreover, a number of illustrative case studies that used HLF into their networks designed for food supply chain management systems have been introduced. The basic design components in each of the applications are reviewed as well as the main goals and desired outcomes.
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Extraction of facial features for detection of human emotions under noisy condition
Статья научная
Affirmation of human faces out of still pictures or picture progressions is an as of now making research field. There are an extensive variety of engagements for structures adjusting to the issue of face limitation and affirmation e.g. exhibit based video coding, face conspicuous confirmation for security structures, look area, and human-PC connection. The acknowledgment and region of the face, and furthermore the extraction of facial features from the photos, are fundamental. In view of assortments in illumination, establishment, visual point and outward appearances, the issue becomes complicated. This paper presents a novel method to extract human facial features for the detection of human emotions (such as “sad”, “happy”, “sorrow” etc.) under noisy conditions. This whole work constitutes better working of a video surveillance system. For detection and extraction of facial features simple formulae are used to represent skin color models depending on the range of HSV (Hue, Saturation, Value) values used for the detection of human skin. Here HSV color model is used because it is fast as well as compatible with human color perception. Additionally, implementation of Probability Neural Network (PNN) enhances the working of the surveillance system. Utilization of PNN expands the ability of surveillance framework as it can give the yield image regardless of whether the information image contains noise in it. The proposed algorithm for the entire task is developed using MATLAB software along with suitable Image Processing Toolbox (IPT).
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Статья научная
As of late, Automatic speech recognition has advanced on account of instruments, for example, natural language processing, and deep learning, among others. It is a framework or put in another way, a gadget that changes a raw signal into computer comprehensible text. The genuine creation of speech is comprised of changes in air pressure that outcomes in pressure wave that our ear and cerebrum comprehend. The vocal tract is utilized to deliver a human speech, which is adjusted by teeth, tongue, and lips. Speech recognition alludes to a machine's ability to perceive human speech and transform it into a computer comprehensible text. Speech recognition is a magnificent illustration of good interaction between humans and computers. In this paper, we introduce the process to extricate the feature from the signal utilizing Mel-frequency cepstral coefficients. Mel-frequency cepstral coefficients are a genuinely far wide and proficient methodology for feature extraction from a sound file. This technique improved the speech recognition process and removes the distortion in the voice. In this manuscript we applied the Mel-frequency filtration process to improve speech and remove the background noise. the Therefore, the proposed methodology gives better performance in the automated speech recognition system.
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Fabrication of a Porous Ceramic Material Suitable for Cost-effective Thermal Insulation of Buildings
Статья научная
The domestication of cost-effective, green, and sustainable building materials is significant towards its massive adoption in the developing countries. The feasibility of developing porous ceramics for cost-effective thermal insulation of buildings was explored in this study using waste materials including granite shifting and sawdust as well as chemical reagents including water glass and sodium hydroxide. Granite shifting and sawdust were dried, processed into powdered form, milled and sieved. Samples of porous ceramics were formulated using varying percentages by weight of granite shifting and sawdust mixed with a constant percentage by weight of water glass and sodium hydroxide in three different cases. The homogenized powder of the formulated composition was uniaxially pressed at 10Mpa. The samples were dried and then sintered in a gas kiln at 8500C for 3 hours. The result revealed water absorption (21.1−56.5%), compressive strength (1.2−7.9Mpa), bulk density (1.44−1.81g/cm3), apparent porosity (38.1−81.3%), and thermal conductivity (0.13−0.54W/m.K). These results indicated that the obtained porous ceramics is a potential material for cost-effective thermal insulation of buildings where a suitable combination of thermal conductivity, porosity, and mechanical strength is required.
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Статья научная
The key of fast identification algorithm of time-varying modal parameter based on subspace tracking is to find efficient and fast subspace-tracking algorithm. This paper presents a new version of NIC(Novel Information Criterion) using two-layer linear neural network learning for subspace tracking. Comparing with the original algorithm, there is no need to set a key control parameter in advance. Simulation experiments show that new algorithm has a faster convergence in the initial period.
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