Search results for: Yield Improvement.
1326 Hardware Stream Cipher Based On LFSR and Modular Division Circuit
Authors: Deepthi P.P., P.S. Sathidevi
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Proposal for a secure stream cipher based on Linear Feedback Shift Registers (LFSR) is presented here. In this method, shift register structure used for polynomial modular division is combined with LFSR keystream generator to yield a new keystream generator with much higher periodicity. Security is brought into this structure by using the Boolean function to combine state bits of the LFSR keystream generator and taking the output through the Boolean function. This introduces non-linearity and security into the structure in a way similar to the Non-linear filter generator. The security and throughput of the suggested stream cipher is found to be much greater than the known LFSR based structures for the same key length.
Keywords: Linear Feedback Shift Register, Stream Cipher, Filter generator, Keystream generator, Modular division circuit
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27271325 A Study of Management Principles Incorporating Corporate Governance and Advocating Ethics to Reduce Fraud at a South African Bank
Authors: Roshan Jelal, Charles Mbohwa
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In today’s world, internal fraud remains one of the most challenging problems within companies worldwide and despite investment in controls and attention given to the problem, the instances of internal fraud has not abated. To the contrary it appears that internal fraud is on the rise especially in the wake of the economic downturn.
Leadership within companies believes that the more sophisticated the controls employed the less likely it would be for employees to pilfer. This is a very antiquated view as investment in controls may not be enough to curtail internal fraud; however, ensuring that a company drives the correct culture and behavior within the organization is likely to yield desired results.
This research aims to understand how creating a strong ethical culture and embedding the principle of good corporate governance impacts on levels of internal fraud with an organization (a South African Bank).
Keywords: Internal Fraud, Corporate Governance, Ethics, South African Reserve Bank, The King Code.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20701324 Carrageenan Properties Extracted From Eucheuma cottonii, Indonesia
Authors: Sperisa Distantina, Wiratni , Moh. Fahrurrozi, Rochmadi
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The effect of extraction solvent upon properties of carrageenan from Eucheuma cottonii was studied. The distilled water and KOH solution (concentration 0.1- 0.5N) were used as the solvent. Extraction process was carried out in water bath equipped by stirrer with constant speed of 275 rpm with a constant ratio of seaweed weight to solvent volume ( 1:50 g/mL) at 86oC for 45 minutes. The extract was then precipitated in 3 volume of 90% ethanol, oven dried at 60oC. Based on experimental data, alkali significantly influenced yield and properties of extracted carrageenan. The extracted carrageenan was found to have essentially identical FTIR spectra to the reference samples of kappa-carrageenan. Increasing the KOH concentration led to carrageenan containing less sulfate content and intrinsic viscosity. The gel strength increased along with the increasing of KOH concentration. The decreasing of intrinsic viscosity value indicates that a polymer degradation occurs during alkali extraction.Keywords: gel strength, sulfate, intrinsic viscosity, Eucheumacottonii
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 60571323 Recent Advances in Energy Materials for Hot Sections of Modern Gas-Turbine Engines
Authors: Zainul Huda
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This presentation reviews recent advances in superalloys and thermal barrier coating (TBC) for application in hot sections of energy-efficient gas-turbine engines. It has been reviewed that in the modern combined-cycle gas turbines (CCGT) applying single-crystal energy materials (SC superalloys) and thermal barrier coatings (TBC), and – in one design – closed-loop steam cooling, thermal efficiency can reach more than 60%. These technological advancements contribute to profitable and clean power generation with reduced emission. Alternatively, the use of advanced superalloys (e.g. GTD-111 superalloy, Allvac 718Plus superalloy) and advanced thermal barrier coatings (TBC) in modern gas-turbines has been shown to yield higher energy-efficiency in power generation.
Keywords: Energy materials, gas turbine engines, superalloy, thermal barrier coating
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27411322 Process Simulation of Ethyl tert-Butyl Ether (ETBE) Production from Naphtha Cracking Wastes
Authors: Pakorn Traiprasertpong, Apichit Svang-Ariyaskul
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The production of ethyl tert-butyl ether (ETBE) was simulated through Aspen Plus. The objective of this work was to use the simulation results to be an alternative platform for ETBE production from naphtha cracking wastes for the industry to develop. ETBE is produced from isobutylene which is one of the wastes in naphtha cracking process. The content of isobutylene in the waste is less than 30% weight. The main part of this work was to propose a process to save the environment and to increase the product value by converting a great majority of the wastes into ETBE. Various processes were considered to determine the optimal production of ETBE. The proposed process increased ETBE production yield by 100% from conventional process with the purity of 96% weight. The results showed a great promise for developing this proposed process in an industrial scale.Keywords: ETBE, process simulation, naphtha cracking, Aspen Plus
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 54331321 SCM Challenges and Opportunitiesin the Timber Construction Sector
Authors: K. Reitner, F. Staberhofer, W. Ortner, M. Gerschberger
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The purpose of this paper is to identify the main challenges faced by companies in the timber construction sector and to provide improvement opportunities that can be implemented on a short-, medium- and long-term basis. To identify the challenges and propose actions for each company a literature review and a multiple case research were conducted using the Quick Scan Audit Methodology. Finally, the findings and outcomes are compared with each other to support companies in the timer construction sector when implementing and restructuring their day-to-day activities.
Keywords: Supply chain management, supply chain challenges and opportunities, timber construction sector.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17771320 Different Approaches for the Design of IFIR Compaction Filter
Authors: Sheeba V.S, Elizabeth Elias
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Optimization of filter banks based on the knowledge of input statistics has been of interest for a long time. Finite impulse response (FIR) Compaction filters are used in the design of optimal signal adapted orthonormal FIR filter banks. In this paper we discuss three different approaches for the design of interpolated finite impulse response (IFIR) compaction filters. In the first method, the magnitude squared response satisfies Nyquist constraint approximately. In the second and third methods Nyquist constraint is exactly satisfied. These methods yield FIR compaction filters whose response is comparable with that of the existing methods. At the same time, IFIR filters enjoy significant saving in the number of multipliers and can be implemented efficiently. Since eigenfilter approach is used here, the method is less complex. Design of IFIR filters in the least square sense is presented.
Keywords: Principal Component Filter Bank, InterpolatedFinite Impulse Response filter, Orthonormal Filter Bank, Eigen Filter.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15781319 Self-Tuning Power System Stabilizer Based on Recursive Least Square Identification and Linear Quadratic Regulator
Authors: J. Ritonja
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Available commercial applications of power system stabilizers assure optimal damping of synchronous generator’s oscillations only in a small part of operating range. Parameters of the power system stabilizer are usually tuned for the selected operating point. Extensive variations of the synchronous generator’s operation result in changed dynamic characteristics. This is the reason that the power system stabilizer tuned for the nominal operating point does not satisfy preferred damping in the overall operation area. The small-signal stability and the transient stability of the synchronous generators have represented an attractive problem for testing different concepts of the modern control theory. Of all the methods, the adaptive control has proved to be the most suitable for the design of the power system stabilizers. The adaptive control has been used in order to assure the optimal damping through the entire synchronous generator’s operating range. The use of the adaptive control is possible because the loading variations and consequently the variations of the synchronous generator’s dynamic characteristics are, in most cases, essentially slower than the adaptation mechanism. The paper shows the development and the application of the self-tuning power system stabilizer based on recursive least square identification method and linear quadratic regulator. Identification method is used to calculate the parameters of the Heffron-Phillips model of the synchronous generator. On the basis of the calculated parameters of the synchronous generator’s mathematical model, the synthesis of the linear quadratic regulator is carried-out. The identification and the synthesis are implemented on-line. In this way, the self-tuning power system stabilizer adapts to the different operating conditions. A purpose of this paper is to contribute to development of the more effective power system stabilizers, which would replace currently used linear stabilizers. The presented self-tuning power system stabilizer makes the tuning of the controller parameters easier and assures damping improvement in the complete operating range. The results of simulations and experiments show essential improvement of the synchronous generator’s damping and power system stability.
Keywords: Adaptive control, linear quadratic regulator, power system stabilizer, recursive least square identification.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11231318 Equality, Friendship, and Violence in Slash or Yaoi Fan Art
Authors: Proud Arunrangsiwed
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Slash or Yaoi fan art is the artwork that contains a homosexual relationship between fictional male characters, who were heterosexual in the original media. Previous belief about Slash or Yaoi fan art is that the fan fiction writers and the fan artists need to see the equality in romantic relationship. They do not prefer the pairing of man and woman, since both genders are not equal. The objectives of the current study are to confirm this belief, and to examine the relationship between equality found in Slash fan art, friendship in original media, and violence contained in fan art. Mean comparisons show that equality could be found in the pairing of hero and hero, but rarely found in the pairing of hero and villain. Regression analysis shows that the level of equality in fan art and friendship in original media are significant predictors of violence contained in fan art. Since villain-related pairings yield a high level of violence in fan art and a low level of equality, researchers of future studies should find the strategies to prevent fans to include villains in their Slash or Yaoi fan art.
Keywords: Equality, fan art, slash, violence, yaoi.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30731317 Composite Relevance Feedback for Image Retrieval
Authors: Pushpa B. Patil, Manesh B. Kokare
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This paper presents content-based image retrieval (CBIR) frameworks with relevance feedback (RF) based on combined learning of support vector machines (SVM) and AdaBoosts. The framework incorporates only most relevant images obtained from both the learning algorithm. To speed up the system, it removes irrelevant images from the database, which are returned from SVM learner. It is the key to achieve the effective retrieval performance in terms of time and accuracy. The experimental results show that this framework had significant improvement in retrieval effectiveness, which can finally improve the retrieval performance.
Keywords: Image retrieval, relevance feedback, wavelet transform.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19931316 Improving Teacher Profesionalism through Certification Program: An Indonesia Case Study
Authors: Triyanto
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Government of Indonesia held a certification program to enhance the professionalism of teachers by using portfolio assessment. This research discusses about the effectiveness of certification programs to enhance the professionalism of teacher in Indonesia. Portfolio assessment method has drawbacks. The certified teachers do not show significant performance improvement. Therefore, the government changes the portfolio assessment method to the education and training for teachers.
Keywords: Profesionalism, Teacher, Certification, Indonesia
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28151315 Forming of Nanodimentional Structure Parts in Carbon Steels
Authors: A. Korchunov, M. Chukin, N. Koptseva, M. Polyakova, A. Gulin
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A way of achieving nanodimentional structural elements in high carbon steel by special kind of heat treatment and cold plastic deformation is being explored. This leads to increasing interlamellar spacing of ferrite-carbide mixture. Decreasing the interlamellar spacing with cooling temperature increasing is determined. Experiments confirm such interlamellar spacing with which high carbon steel demonstrates the highest treatment and hardening capability. Total deformation degree effect on interlamellar spacing value in a ferrite-carbide mixture is obtained. Mechanical experiments results show that high carbon steel after heat treatment and repetitive cold plastic deformation possesses high tensile strength and yield strength keeping good percentage elongation.
Keywords: High-carbon steel, nanodimensional structural element, interlamellar spacing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13401314 Comparative Analysis of Photovoltaic Systems
Authors: Irtaza M. Syed, Kaamran Raahemifar
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This paper presents comparative analysis of photovoltaic systems (PVS) and propose practical techniques to improve operational efficiency of the PVS. The best engineering and construction practices for PVS are identified and field oriented recommendation are made. Comparative analysis of central and string inverter based, as well as 600 and 1000VDC PVS are performed. In addition, direct current (DC) and alternating current (AC) photovoltaic (PV) module based systems are compared. Comparison shows that 1000V DC String Inverters based PVS is the best choice.Keywords: Photovoltaic module, photovoltaic systems, operational efficiency improvement, comparative analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22981313 Internal Loading Distribution in Statically Loaded Ball Bearings, Subjected to a Combined Radial and Thrust Load, Including the Effects of Temperature and Fit
Authors: Mário C. Ricci
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A new, rapidly convergent, numerical procedure for internal loading distribution computation in statically loaded, singlerow, angular-contact ball bearings, subjected to a known combined radial and thrust load, which must be applied so that to avoid tilting between inner and outer rings, is used to find the load distribution differences between a loaded unfitted bearing at room temperature, and the same loaded bearing with interference fits that might experience radial temperature gradients between inner and outer rings. For each step of the procedure it is required the iterative solution of Z + 2 simultaneous nonlinear equations – where Z is the number of the balls – to yield exact solution for axial and radial deflections, and contact angles.Keywords: Ball, Bearing, Static, Load, Iterative, Numerical, Method, Temperature, Fit.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17861312 The Impact Factors of the Environmental Pollution and Workers Health in Printing Industry
Authors: Kiurski J., Marić B., Djaković V., Adamović S., Oros I., Krstić J.
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This paper presents the study of parameters affecting the environment protection in the printing industry. The paper has also compared LCA studies performed within the printing industry in order to identify common practices, limitations, areas for improvement, and opportunities for standardization. This comparison is focused on the data sources and methodologies used in the printing pollutants register. The presented concepts, methodology and results represent the contribution to the sustainable development management. Furthermore, the paper analyzes the result of the quantitative identification of hazardous substances emitted in printing industry of Novi Sad.Keywords: LCA, parameters of pollution, printing industry, register
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19121311 Relaxing Convergence Constraints in Local Priority Hysteresis Switching Logic
Authors: Mubarak Alhajri
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This paper addresses certain inherent limitations of local priority hysteresis switching logic. Our main result establishes that under persistent excitation assumption, it is possible to relax constraints requiring strict positivity of local priority and hysteresis switching constants. Relaxing these constraints allows the adaptive system to reach optimality which implies the performance improvement. The unconstrained local priority hysteresis switching logic is examined and conditions for global convergence are derived.Keywords: Adaptive control, convergence, hysteresis constant, hysteresis switching.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8911310 Application of Data Envelopment Analysis to Assess Quality Management Efficiency
Authors: Chuen Tse Kuah, Kuan Yew Wong, Farzad Behrouzi
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This paper is aimed to give an illustration on the application of Data Envelopment Analysis (DEA) as a tool to assess Quality Management (QM) efficiency. A variant of DEA, slack based measure (SBM) is used for this purpose. From this study, it is found that DEA is suitable to measure QM efficiency and give improvement suggestions to the inefficient QM.Keywords: Quality Management, Data Envelopment Analysis, Slack Based Measure, Efficiency Measurement.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20901309 Development of AA2024 Matrix Composites Reinforced with Micro Yttrium through Cold Compaction with Superior Mechanical Properties
Authors: C. H. S. Vidyasagar, D. B. Karunakar
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In this present work, five different composite samples with AA2024 as matrix and varying amounts of yttrium (0.1-0.5 wt.%) as reinforcement are developed through cold compaction. The microstructures of the developed composite samples revealed that the yttrium reinforcement caused grain refinement up to 0.3 wt.% and beyond which the refinement is not effective. The microstructure revealed Al2Cu precipitation which strengthened the composite up to 0.3 wt.% yttrium reinforcement. Upon further increase in yttrium reinforcement, the intermetallics and the precipitation coarsen and their corresponding strengthening effect decreases. The mechanical characterization revealed that the composite sample reinforced with 0.3 wt.% yttrium showed highest mechanical properties like 82 HV of hardness, 276 MPa Ultimate Tensile Strength (UTS), 229 MPa Yield Strength (YS) and an elongation (EL) of 18.9% respectively. However, the relative density of the developed composites decreased with the increase in yttrium reinforcement.
Keywords: Mechanical properties, AA 2024 matrix, yttrium reinforcement, cold compaction, precipitation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6581308 Investigation of Thin Film Cathode Prepared by Synthesized Nano Pyrite
Authors: S. Kowsari, M. Aghaziarati
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Pyrite (FeS2) is a promising candidate for cathode materials in batteries because of it`s high theoretical capacity, low cost and non-toxicity. In this study, nano size iron disulfide thin film was prepared on graphite substrate through a new method as battery cathode. In this way, acetylene black and poly vinylidene fluoride were used as electron conductor and binder, respectively. Fabricated thin films were analyzed by XRD and SEM. These results and electrochemical data confirm improvement of battery discharge capacity in comparison with commercial type of pyrite.Keywords: Nano pyrite, Thin film, Battery cathode, capacity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19341307 Energy Evaluation and Utilization of Cassava Peel for Lactating Dairy Cows
Authors: Pipat Lounglawan, Yutthapong Sornwongkaew, Wassana Lounglawan, Wisitiporn Suksombat
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The experiment was then conducted to investigate the effect of cassava peel addition in the concentrate on the performance of lactating dairy cows. Twenty four Holstein Friesian crossbred (>87.5% Holstein Friesian) lactating dairy cows in mid lactation; averaging 12.2+2.1 kg of milk, 119+45 days in milk, 44.1+6.2 months old and 449+33 kg live weight, were stratified for milk yield, days in milk, age, stage of lactation and body weight, and then randomly allocated to three treatment groups. The first, second and third groups were fed concentrates containing the respective cassava peel, 0, 20 and 40%. All cows were fed ad libitum corn silage and freely access to clean water. Dry matter intake, 4%FCM, milk composition and body weight change were affected (P<0.05) by the third treatments (40%). The present study indicated that 20% cassava peel can be used in the concentrate for lactating dairy cows.Keywords: Cassava peel, Energy evaluation, Milk production, Dairy cattle
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20501306 A Reduced-Bit Multiplication Algorithm for Digital Arithmetic
Authors: Harpreet Singh Dhillon, Abhijit Mitra
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A reduced-bit multiplication algorithm based on the ancient Vedic multiplication formulae is proposed in this paper. Both the Vedic multiplication formulae, Urdhva tiryakbhyam and Nikhilam, are first discussed in detail. Urdhva tiryakbhyam, being a general multiplication formula, is equally applicable to all cases of multiplication. It is applied to the digital arithmetic and is shown to yield a multiplier architecture which is very similar to the popular array multiplier. Due to its structure, it leads to a high carry propagation delay in case of multiplication of large numbers. Nikhilam Sutra, on the other hand, is more efficient in the multiplication of large numbers as it reduces the multiplication of two large numbers to that of two smaller numbers. The framework of the proposed algorithm is taken from this Sutra and is further optimized by use of some general arithmetic operations such as expansion and bit-shifting to take advantage of bit-reduction in multiplication. We illustrate the proposed algorithm by reducing a general 4x4-bit multiplication to a single 2 x 2-bit multiplication operation.
Keywords: Multiplication, algorithm, Vedic mathematics, digital arithmetic, reduced-bit.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 34571305 Graft Copolymerization of Methyl Methacrylate onto Cellulose in Homogeneous Medium – Effect of Solvent and Initiator
Authors: B. Tosh, C. R. Routray
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Homogeneous graft copolymerization of methyl methacrylate (MMA) onto cellulose was carried out in N, N – dimethyl acetamide/LiCl (DMAc/LiCl) and dimethyl sulfoxide/ paraformaldehyde (DMSO/PF) solvent system taking ceric ammonium nitrate (CAN), benzoyl peroxide (BPO) and tin (II)-2-ethyl hexanoate [Sn(Oct)2] as initiators. Different grafting parameters like graft yield (GY), grafting efficiency (GE) and total conversion of monomer to polymer (TC) were evaluated at different reaction conditions of temperature, time, and variation of the amount of monomer and initiator. The viscosity average molecular weight of grafted PMMA and number of grafts per cellulose chain were also calculated. The products were characterized by FT-IR and 1H-NMR analyses and possible reaction mechanisms were deduced. Thermal degradation of the grafted products was also studied by thermo-gravimetric analysis (TG) and differential thermo-gravimetry (DTG).
Keywords: Grafting, grafting efficiency, homogeneous medium, methyl methacrylate.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 31841304 Method to Improve Channel Coding Using Cryptography
Authors: Ayyaz Mahmood
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A new approach for the improvement of coding gain in channel coding using Advanced Encryption Standard (AES) and Maximum A Posteriori (MAP) algorithm is proposed. This new approach uses the avalanche effect of block cipher algorithm AES and soft output values of MAP decoding algorithm. The performance of proposed approach is evaluated in the presence of Additive White Gaussian Noise (AWGN). For the verification of proposed approach, computer simulation results are included.Keywords: Advanced Encryption Standard (AES), Avalanche Effect, Maximum A Posteriori (MAP), Soft Input Decryption (SID).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19471303 Deployment of Service Quality Characteristics
Authors: Shuki Dror
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This work discusses an innovative methodology for deployment of service quality characteristics. Four groups of organizational features that may influence the quality of services are identified: human resource, technology, planning, and organizational relationships. A House of Service Quality (HOSQ) matrix is built to extract the desired improvement in the service quality characteristics and to translate them into a hierarchy of important organizational features. The Mean Square Error (MSE) criterion enables the pinpointing of the few essential service quality characteristics to be improved as well as selection of the vital organizational features. The method was implemented in an engineering supply enterprise and provides useful information on its vital service dimensions.Keywords: HOQ, organizational features, service quality.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18661302 A Meta-Heuristic Algorithm for Set Covering Problem Based on Gravity
Authors: S. Raja Balachandar, K. Kannan
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A new Meta heuristic approach called "Randomized gravitational emulation search algorithm (RGES)" for solving large size set covering problems has been designed. This algorithm is found upon introducing randomization concept along with the two of the four primary parameters -velocity- and -gravity- in physics. A new heuristic operator is introduced in the domain of RGES to maintain feasibility specifically for the set covering problem to yield best solutions. The performance of this algorithm has been evaluated on a large set of benchmark problems from OR-library. Computational results showed that the randomized gravitational emulation search algorithm - based heuristic is capable of producing high quality solutions. The performance of this heuristic when compared with other existing heuristic algorithms is found to be excellent in terms of solution quality.
Keywords: Set covering problem, velocity, gravitational force, Newton's law, meta heuristic, combinatorial optimization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22331301 Rheological Behaviors of Crude Oil in the Presence of Water
Authors: Madjid Meriem-Benziane, Hamou Zahloul
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The rheological properties of light crude oil and its mixture with water were investigated experimentally. These rheological properties include steady flow behavior, yield stress, transient flow behavior, and viscoelastic behavior. A RheoStress RS600 rheometer was employed in all of the rheological examination tests. The light crude oil exhibits a Newtonian and for emulsion exhibits a non-Newtonian shear thinning behavior over the examined shear rate range of 0.1–120 s-1. In first time, a series of samples of crude oil from the Algerian Sahara has been tested and the results expressed in terms of τ=f(γ) have demonstrated their Newtonian character for the temperature included in [20°C, 70°C]. In second time and at T=20°C, the oil-water emulsions (30%, 50% and 70%) by volume of water), thermodynamically stable, have demonstrated a non-Newtonian rheological behavior that is to say, Herschel-Bulkley and Bingham types. For each type of crude oil-water emulsion, the rheological parameters are calculated by numerical treatment of results.
Keywords: Crude oil Algerian, Emulsion, Newtonian, Non- Newtonian, viscosity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 34181300 A Time-Reducible Approach to Compute Determinant |I-X|
Authors: Wang Xingbo
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Computation of determinant in the form |I-X| is primary and fundamental because it can help to compute many other determinants. This article puts forward a time-reducible approach to compute determinant |I-X|. The approach is derived from the Newton’s identity and its time complexity is no more than that to compute the eigenvalues of the square matrix X. Mathematical deductions and numerical example are presented in detail for the approach. By comparison with classical approaches the new approach is proved to be superior to the classical ones and it can naturally reduce the computational time with the improvement of efficiency to compute eigenvalues of the square matrix.Keywords: Algorithm, determinant, computation, eigenvalue, time complexity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11561299 Throughput Optimization on Wireless Networks by Increasing the Maximum Transmission Unit
Authors: Edward Guillén, Stephanne Rodríguez, Jhordany Rodríguez
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Throughput enhancement can be achieved with two main approaches. The first one is by the increase of transmission rate and the second one is reducing the control traffic. This paper focuses on how the throughput can be enhanced by increasing Maximum Transmission Unit -MTU. Transmission of larger packets can cause a throughput improvement by reducing IP overhead. Analysis results are obtained by a mathematical model and simulation tools with a main focus on wireless channels.
Keywords: 802.11, Maximum Transfer Unit, throughput enhancement, wireless networks.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 35761298 Hot-Spot Blob Merging for Real-Time Image Segmentation
Authors: K. Kraus, M. Uiberacker, O. Martikainen, R. Reda
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One of the major, difficult tasks in automated video surveillance is the segmentation of relevant objects in the scene. Current implementations often yield inconsistent results on average from frame to frame when trying to differentiate partly occluding objects. This paper presents an efficient block-based segmentation algorithm which is capable of separating partly occluding objects and detecting shadows. It has been proven to perform in real time with a maximum duration of 47.48 ms per frame (for 8x8 blocks on a 720x576 image) with a true positive rate of 89.2%. The flexible structure of the algorithm enables adaptations and improvements with little effort. Most of the parameters correspond to relative differences between quantities extracted from the image and should therefore not depend on scene and lighting conditions. Thus presenting a performance oriented segmentation algorithm which is applicable in all critical real time scenarios.Keywords: Image segmentation, Model-based, Region growing, Blob Analysis, Occlusion, Shadow detection, Intelligent videosurveillance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15061297 Linear Cryptanalysis for a Chaos-Based Stream Cipher
Authors: Ruming Yin, Jian Yuan, Qiuhua Yang, Xiuming Shan, Xiqin Wang
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Linear cryptanalysis methods are rarely used to improve the security of chaotic stream ciphers. In this paper, we apply linear cryptanalysis to a chaotic stream cipher which was designed by strictly using the basic design criterion of cryptosystem – confusion and diffusion. We show that this well-designed chaos-based stream cipher is still insecure against distinguishing attack. This distinguishing attack promotes the further improvement of the cipher.
Keywords: Stream cipher, chaos, linear cryptanalysis, distinguishing attack.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1752