Search results for: enhanced valueexperience
563 On Phase Based Stereo Matching and Its Related Issues
Authors: Andr´as R¨ovid, Takeshi Hashimoto
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The paper focuses on the problem of the point correspondence matching in stereo images. The proposed matching algorithm is based on the combination of simpler methods such as normalized sum of squared differences (NSSD) and a more complex phase correlation based approach, by considering the noise and other factors, as well. The speed of NSSD and the preciseness of the phase correlation together yield an efficient approach to find the best candidate point with sub-pixel accuracy in stereo image pairs. The task of the NSSD in this case is to approach the candidate pixel roughly. Afterwards the location of the candidate is refined by an enhanced phase correlation based method which in contrast to the NSSD has to run only once for each selected pixel.
Keywords: Stereo matching, Sub-pixel accuracy, phase correlation, SVD, NSSD.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1851562 Performance Evaluation of TCP Vegas versus Different TCP Variants in Homogeneous and Heterogeneous Wired Networks
Authors: B. S. Yew, B. L. Ong, R. B. Ahmad
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A study on the performance of TCP Vegas versus different TCP variants in homogeneous and heterogeneous wired networks are performed via simulation experiment using network simulator (ns-2). This performance evaluation prepared a comparison medium for the performance evaluation of enhanced-TCP Vegas in wired network and for wireless network. In homogeneous network, the performance of TCP Tahoe, TCP Reno, TCP NewReno, TCP Vegas and TCP SACK are analyzed. In heterogeneous network, the performances of TCP Vegas against TCP variants are analyzed. TCP Vegas outperforms other TCP variants in homogeneous wired network. However, TCP Vegas achieves unfair throughput in heterogeneous wired network.Keywords: TCP Vegas, Homogeneous, Heterogeneous, WiredNetwork.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1705561 A Review on Enhanced Dynamic Clustering in WSN
Authors: M. Sangeetha, A. Sabari, K. Elakkiya
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Recent advancement in wireless internetworking has presented a number of dynamic routing protocols based on sensor networks. At present, a number of revisions are made based on their energy efficiency, lifetime and mobility. However, to the best of our knowledge no extensive survey of this special type has been prepared. At present, review is needed in this area where cluster-based structures for dynamic wireless networks are to be discussed. In this paper, we examine and compare several aspects and characteristics of some extensively explored hierarchical dynamic clustering protocols in wireless sensor networks. This document also presents a discussion on the future research topics and the challenges of dynamic hierarchical clustering in wireless sensor networks.Keywords: Dynamic cluster, Hierarchical clustering, Wireless sensor networks.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1368560 Viability of Bradyrhizobium japanicum on Soybean Seeds Enhanced by Magnetite Nanoparticles during Desiccation
Authors: M. R. Ghalamboran, J. J. Ramsden
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The aim of this study was to investigate whether magnetite nanoparticles affect the viability of Bradyrhizobium japanicum cells residing on the surface of soybean seeds during desiccation. Different concentrations of nanoparticles suspended in liquid medium, mixed with and adhering to Bradyrhizobium japanicum, were investigated at two temperatures, using both soybean seeds and glass beads as surrogates. Statistical design was a complete randomized block (CRB) in a factorial 6×2×2×6 experimental arrangement with four replications. The most important variable was the viability of Bradyrhizobium on the surface of the seeds. The nanoparticles increased Bradyrhizobium viability and inoculated seeds stored at low temperature had greater viability when nanoparticles had been added. At the optimum nanoparticle concentration, 50% bacterium viability on the seeds was retained after 5 days at 4ºC. Possible explanations for the observed effects are proposed.Keywords: Bradyrhizobium japanicum, magnetitenanoparticles, soybean seed, viability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1280559 The Effect of Self-Efficacy on Emotional Intelligence and Well-Being among Tour Guides
Authors: Jennifer Chen-Hua Min
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The concept of self-efficacy refers to people’s beliefs in their ability to perform certain behaviors and cope with environmental demands. As such, self-efficacy plays a key role in linking ability to performance. Therefore, this study examines the relationships of self-efficacy, emotional intelligence (EI), and well-being among tour guides, who act as intermediaries between tourists and an unfamiliar environment and significantly influence tourists’ impressions of a destination. Structural equation modeling (SEM) is used to identify the relationships between these factors. The results found that self-efficacy is positively associated with EI and well-being, and a positive link was seen between EI and well-being. This study has practical implications, as the results can facilitate the development of interventions for enhancing tour guides’ EI and self-efficacy competencies, which will benefit them in terms of both enhanced achievements and improved psychological happiness and well-being.
Keywords: Self-efficacy, tour guides, tourism, emotional intelligence.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1453558 Study of Ether Species Effects on Physicochemical Properties of Palm Oil Ether Monoesters as Novel Biodiesels
Authors: Hejun Guo, Shenghua Liu
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Five palm oil ether monoesters utilized as novel biodiesels were synthesized and structurally identified in the paper. The investigation was made on the effect of ether species on physicochemical properties of the palm oil ether monoesters. The results showed that density, kinematic viscosity, smoke point, and solidifying point increase linearly with their –CH2 group number in certain relationships. Cetane number is enhanced whereas heat value decreases linearly with –CH2 group number. In addition, the influencing regularities of the volumetric content of the palm oil ether monoesters on the fuel properties were also studied when the ether monoesters are used as diesel fuel additives.
Keywords: Biodiesel, palm oil ether monoester, ether species, physicochemical property.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1526557 Educational Values of Virtual Reality: The Case of Spatial Ability
Authors: Elinda Ai-Lim Lee, Kok Wai Wong, Chun Che Fung
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The use of Virtual Reality (VR) in schools and higher education is proliferating. Due to its interactive and animated features, it is regarded as a promising technology to increase students- spatial ability. Spatial ability is assumed to have a prominent role in science and engineering domains. However, research concerning individual differences such as spatial ability in the context of VR is still at its infancy. Moreover, empirical studies that focus on the features of VR to improve spatial ability are to date rare. Thus, this paper explores the possible educational values of VR in relation to spatial ability to call for more research concerning spatial ability in the context of VR based on studies in computerbased learning. It is believed that the incorporation of state-of-the-art VR technology for educational purposes should be justified by the enhanced benefits for the target learners.
Keywords: Ability-as-compensator, ability-as-enhancer, spatialability, virtual reality.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2182556 Framework of TAZ_OPT Model for Ambulance Location and Allocation Problem
Authors: Adibah Shuib, Zati Aqmar Zaharudin
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Our study is concerned with the development of an Emergency Medical Services (EMS) ambulance location and allocation model called the Time-based Ambulance Zoning Optimization Model (TAZ_OPT). This paper presents the framework of the study. The model is formulated using the goal programming (GP), where the goals are to determine the satellite locations of ambulances and the number of ambulances to be allocated at these locations. The model aims at maximizing the expected demand coverage based on probability of reaching the emergency location within targetted time, and minimizing the ambulance busyness likelihood value. Among the benefits of the model is the increased accessibility and availability of ambulances, thus, enhanced quality of the EMS ambulance services.
Keywords: Optimization, Ambulance Location, Location facilities.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2158555 LQG Flight Control of VTAV for Enhanced Situational Awareness
Authors: Igor Astrov, Mikhail Pikkov, Rein Paluoja
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This paper focuses on a critical component of the situational awareness (SA), the control of autonomous vertical flight for vectored thrust aerial vehicle (VTAV). With the SA strategy, we proposed a linear-quadratic-Gaussian (LQG) flight control procedure for an unmanned helicopter model with vectored thrust configuration. This LQG control for chosen model of VTAV has been verified by simulation of take-off and landing maneuvers using software package Simulink and demonstrated good performance for fast flight stabilization of model, consequently, fast SA with economy in energy can be asserted during search-and-rescue operations.
Keywords: Linear-Quadratic-Gaussian (LQG) controller, situational awareness, vectored thrust aerial vehicle.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1821554 Doping of Conveyor Belt Materials with Nanostructured Fillers to Adapt Innovative Performance Characteristics
Authors: S. Falkenberg, L. Overmeyer
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The “conveyor belt" as a product represents a complex high performance component with a wide range of different applications. Further development of these highly complex components demands an integration of new technologies and new enhanced materials. In this context nanostructured fillers appear to have a more promising effect on the performance of the conveyor belt composite than conventional micro-scaled fillers. Within the project “DotTrans" nanostructured fillers, for example silicon dioxide, are used to optimize performance parameters of conveyor belt systems. The objective of the project includes operating parameters like energy consumption or friction characteristics as well as adaptive parameters like cut or wear resistance.Keywords: Conveyor belt, nanostructured fillers, wear resistance, friction characteristics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2132553 Improved MARS Ciphering Using a Metamorphic-Enhanced Function
Authors: Moataz M. Naguib, Hatem Khater, A. Baith Mohamed
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MARS is a shared-key (symmetric) block cipher algorithm supporting 128-bit block size and a variable key size of between 128 and 448 bits. MARS has a several rounds of cryptographic core that is designed to take advantage of the powerful results for improving security/performance tradeoff over existing ciphers. In this work, a new function added to improve the ciphering process it is called, Meta-Morphic function. This function use XOR, Rotating, Inverting and No-Operation logical operations before and after encryption process. The aim of these operations is to improve MARS cipher process and makes a high confusion criterion for the Ciphertext.
Keywords: AES, MARS, Metamorphic, Cryptography, Block Cipher.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2030552 An Effective Hybrid Genetic Algorithm for Job Shop Scheduling Problem
Authors: Bin Cai, Shilong Wang, Haibo Hu
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The job shop scheduling problem (JSSP) is well known as one of the most difficult combinatorial optimization problems. This paper presents a hybrid genetic algorithm for the JSSP with the objective of minimizing makespan. The efficiency of the genetic algorithm is enhanced by integrating it with a local search method. The chromosome representation of the problem is based on operations. Schedules are constructed using a procedure that generates full active schedules. In each generation, a local search heuristic based on Nowicki and Smutnicki-s neighborhood is applied to improve the solutions. The approach is tested on a set of standard instances taken from the literature and compared with other approaches. The computation results validate the effectiveness of the proposed algorithm.
Keywords: Genetic algorithm, Job shop scheduling problem, Local search, Meta-heuristic algorithm
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1644551 Highly Efficient White Light-emitting Diodes Based on Layered Quantum Dot-Phosphor Nanocomposites as Converting Materials
Authors: J. Y. Woo, J. Lee, N. Kim, C.-S. Han
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This paper reports on the enhanced photoluminescence (PL) of nanocomposites through the layered structuring of phosphor and quantum dot (QD). Green phosphor of Sr2SiO4:Eu, red QDs of CdSe/CdS/CdZnS/ZnS core-multishell, and thermo-curable resin were used for this study. Two kinds of composite (layered and mixed) were prepared, and the schemes for optical energy transfer between QD and phosphor were suggested and investigated based on PL decay characteristics. It was found that the layered structure is more effective than the mixed one in the respects of PL intensity, PL decay and thermal loss. When this layered nanocomposite (QDs on phosphor) is used to make white light emitting diode (LED), the brightness is increased by 37 %, and the color rendering index (CRI) value is raised to 88.4 compared to the mixed case of 80.4.Keywords: Quantum Dot, Nanocomposites, Photoluminescence, Light Emitting Diode
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3190550 Detection of Bias in GPS satellites- Measurements for Enhanced Measurement Integrity
Authors: Mamoun F. Abdel-Hafez
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In this paper, the detection of a fault in the Global Positioning System (GPS) measurement is addressed. The class of faults considered is a bias in the GPS pseudorange measurements. This bias is modeled as an unknown constant. The fault could be the result of a receiver fault or signal fault such as multipath error. A bias bank is constructed based on set of possible fault hypotheses. Initially, there is equal probability of occurrence for any of the biases in the bank. Subsequently, as the measurements are processed, the probability of occurrence for each of the biases is sequentially updated. The fault with a probability approaching unity will be declared as the current fault in the GPS measurement. The residual formed from the GPS and Inertial Measurement Unit (IMU) measurements is used to update the probability of each fault. Results will be presented to show the performance of the presented algorithm.
Keywords: Estimation and filtering, Statistical data analysis, Faultdetection and identification.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1956549 A New Algorithm for Enhanced Robustness of Copyright Mark
Authors: Harsh Vikram Singh, S. P. Singh, Anand Mohan
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This paper discusses a new heavy tailed distribution based data hiding into discrete cosine transform (DCT) coefficients of image, which provides statistical security as well as robustness against steganalysis attacks. Unlike other data hiding algorithms, the proposed technique does not introduce much effect in the stegoimage-s DCT coefficient probability plots, thus making the presence of hidden data statistically undetectable. In addition the proposed method does not compromise on hiding capacity. When compared to the generic block DCT based data-hiding scheme, our method found more robust against a variety of image manipulating attacks such as filtering, blurring, JPEG compression etc.
Keywords: Information Security, Robust Steganography, Steganalysis, Pareto Probability Distribution function.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1789548 Design Histories for Enhanced Concurrent Structural Design
Authors: Adam Sobey, James Blake, Ajit Shenoi
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The leisure boatbuilding industry has tight profit margins that demand that boats are created to a high quality but with low cost. This requirement means reduced design times combined with increased use of design for production can lead to large benefits. The evolutionary nature of the boatbuilding industry can lead to a large usage of previous vessels in new designs. With the increase in automated tools for concurrent engineering within structural design it is important that these tools can reuse this information while subsequently feeding this to designers. The ability to accurately gather this materials and parts data is also a key component to these tools. This paper therefore aims to develop an architecture made up of neural networks and databases to feed information effectively to the designers based on previous design experience.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1160547 Conjugate Free Convection in a Square Cavity Filled with Nanofluid and Heated from Below by Spatial Wall Temperature
Authors: Ishak Hashim, Ammar Alsabery
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The problem of conjugate free convection in a square cavity filled with nanofluid and heated from below by spatial wall temperature is studied numerically using the finite difference method. Water-based nanofluid with copper nanoparticles are chosen for the investigation. Governing equations are solved over a wide range of nanoparticle volume fraction (0 ≤ φ ≤ 0.2), wave number ((0 ≤ λ ≤ 4) and thermal conductivity ratio (0.44 ≤ Kr ≤ 6). The results presented for values of the governing parameters in terms of streamlines, isotherms and average Nusselt number. It is found that the flow behavior and the heat distribution are clearly enhanced with the increment of the non-uniform heating.Keywords: Conjugate free convection, nanofluid, spatial temperature.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1637546 Comparison of Finite-Element and IEC Methods for Cable Thermal Analysis under Various Operating Environments
Authors: M. S. Baazzim, M. S. Al-Saud, M. A. El-Kady
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In this paper, steady-state ampacity (current carrying capacity) evaluation of underground power cable system by using analytical and numerical methods for different conditions (depth of cable, spacing between phases, soil thermal resistivity, ambient temperature, wind speed), for two system voltage level were used 132 and 380 kV. The analytical method or traditional method that was used is based on the thermal analysis method developed by Neher-McGrath and further enhanced by International Electrotechnical Commission (IEC) and published in standard IEC 60287. The numerical method that was used is finite element method and it was recourse commercial software based on finite element method.
Keywords: Cable ampacity, Finite element method, underground cable, thermal rating.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5845545 Nonlinear Conduction in Pure and Doped ZnO Varistors
Authors: A. Sedky, E. El-Suheel
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We report here structural, mechanical and I-V characteristics of Zn1-xMxO ceramic samples with various x and M. It is found that the considered dopants does not influence the wellknown peaks related to wurtzite structure of ZnO ceramics, while the shape and size of grains are clearly affected. Average crystalline diameters, deduced from XRD are between 42 nm and 54 nm, which are 70 times lower than those obtained from SEM micrographs. Interestingly, the potential barrier could be formed by adding Cu up to 0.20, and it is completely deformed by 0.025 Ni additions. The breakdown field could be enhanced up to 4138 V/cm by 0.025 Cu additions, followed by a decrease with further increase of Cu . On the other hand a gradual decrease in VHN is reported for both dopants and their values are higher in Ni samples as compared to Cu samples. The electrical conductivity is generally improved by Ni, while addition of Cu improved it only in the over doped region (≥ 0.10). These results are discussed in terms of the difference of valency and ferromagnetic ordering for both dopants as compared to undoped sample.Keywords: Semiconductors, Chemical Synthesis, Impurities and Electronic Transport
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2108544 The Influence of Substrate Bias on the Mechanical Properties of a W- and S-containing DLC-based Solid-lubricant Film
Authors: Guojia Ma, Guoqiang Lin, Shuili Gong, Gang Sun, Dawang Wang
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A diamond-like carbon (DLC) based solid-lubricant film was designed and DLC films were successfully prepared using a microwave plasma enhanced magnetron sputtering deposition technology. Post-test characterizations including Raman spectrometry, X-ray diffraction, nano-indentation test, adhesion test, friction coefficient test were performed to study the influence of substrate bias voltage on the mechanical properties of the W- and S-doped DLC films. The results indicated that the W- and S-doped DLC films also had the typical structure of DLC films and a better mechanical performance achieved by the application of a substrate bias of -200V.Keywords: Adhesive Strength, Coefficient of Friction, Substrate Bias, W- and S-doped DLC film
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1947543 An Enhanced Artificial Neural Network for Air Temperature Prediction
Authors: Brian A. Smith, Ronald W. McClendon, Gerrit Hoogenboom
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The mitigation of crop loss due to damaging freezes requires accurate air temperature prediction models. An improved model for temperature prediction in Georgia was developed by including information on seasonality and modifying parameters of an existing artificial neural network model. Alternative models were compared by instantiating and training multiple networks for each model. The inclusion of up to 24 hours of prior weather information and inputs reflecting the day of year were among improvements that reduced average four-hour prediction error by 0.18°C compared to the prior model. Results strongly suggest model developers should instantiate and train multiple networks with different initial weights to establish appropriate model parameters.
Keywords: Time-series forecasting, weather modeling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1853542 Thermoplastic Composites with Reduced Discoloration and Enhanced Fire-Retardant Property
Authors: Peng Cheng, Liqing Wei, Hongyu Chen, Ruomiao Wang
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This paper discusses a light-weight reinforced thermoplastic (LWRT) composite with superior fire retardancy. This porous LWRT composite is manufactured using polyolefin, fiberglass, and fire retardant additives via a wet-lay process. However, discoloration of the LWRT can be induced by various mechanisms, which may be a concern in the building and construction industry. It is commonly understood that discoloration is strongly associated with the presence of phenolic antioxidant(s) and NOx. The over-oxidation of phenolic antioxidant(s) is probably the root-cause of the discoloration (pinking/yellowing). Hanwha Azdel, Inc. developed a LWRT with fire-retardant property of ASTM E84-Class A specification, as well as negligible discoloration even under harsh conditions. In addition, this thermoplastic material is suitable for secondary processing (e.g. compression molding) if necessary.Keywords: Discoloration, fire-retardant, thermoplastic composites, wet-lay process.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 774541 Numerical Investigation of the Effect of Flow and Heat Transfer of a Semi-Cylindrical Obstacle Located in a Channel
Authors: Omer F. Can, Nevin Celik
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In this study, a semi-cylinder obstacle placed in a channel is handled to determine the effect of flow and heat transfer around the obstacle. Both faces of the semi-cylinder are used in the numerical analysis. First, the front face of the semi-cylinder is stated perpendicular to flow, than the rear face is placed. The study is carried out numerically, by using commercial software ANSYS 11.0. The well-known κ-ε model is applied as the turbulence model. Reynolds number is in the range of 104 to 105 and air is assumed as the flowing fluid. The results showed that, heat transfer increased approximately 15 % in the front faze case, while it enhanced up to 28 % in the rear face case.Keywords: External flow, semi-cylinder obstacle, heat transfer, friction.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3171540 An Efficient Gaussian Noise Removal Image Enhancement Technique for Gray Scale Images
Authors: V. Murugan, R. Balasubramanian
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Image enhancement is a challenging issue in many applications. In the last two decades, there are various filters developed. This paper proposes a novel method which removes Gaussian noise from the gray scale images. The proposed technique is compared with Enhanced Fuzzy Peer Group Filter (EFPGF) for various noise levels. Experimental results proved that the proposed filter achieves better Peak-Signal-to-Noise-Ratio PSNR than the existing techniques. The proposed technique achieves 1.736dB gain in PSNR than the EFPGF technique.
Keywords: Gaussian noise, adaptive bilateral filter, fuzzy peer group filter, switching bilateral filter, PSNR
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2473539 Effects of Skim Milk Powder Supplementation to Soy Yogurts on Biotransformation of Isoflavone Glycosides to Biologically Active Forms during Storage
Authors: T. T. Pham, N. P. Shah
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Three batches of yogurts were made with soy protein isolate (SPI) supplemented with 2% (S2), 4% (S4) or 6% (S6) of skim milk powder (SMP). The fourth batch (control; S0) was prepared from SPI without SMP supplementation. Lactobacillus delbrueckii ssp. bulgaricus ATCC 11842 (Lb 11842) and Streptococcus thermophilus ST 1342 (ST 1342) were used as the starter culture. Biotransformation of the inactive forms, isoflavone glycosides (IG) to biologically active forms, isoflavone aglycones (IA), was determined during 28 d storage. The viability of both microorganisms was significantly higher (P < 0.05) in S2, S4, and S6 than that in S0. The ratio of lactic acid/acetic acid in S0 was in the range of 15.53 – 22.31 compared to 7.24 – 12.81 in S2, S4 and S6. The biotransformation of IG to IA in S2, S4 and S6 was also enhanced by 9.9 -13.3% compared to S0.Keywords: Isoflavone aglycones, isoflavone glycosides, skim milk powder and soy yogurt.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1933538 Performance of Power System Stabilizer (UNITROL D) in Benghazi North Power Plant
Authors: T. Hussein
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The use of power system stabilizers (PSSs) to damp power system swing mode of oscillations is practical important. Our purpose is to retune the power system stabilizer (PSS1A) parameters in Unitrol D produced by ABB– was installed in 1995in Benghazi North Power Plants (BNPPs) at General Electricity Company of Libya (GECOL). The optimal values of the power system stabilizer (PSS1A) parameters are determined off-line by a particle swarm optimization technique (PSO). The objective is to damp the local and inter-area modes of oscillations that occur following power system disturbances. The retuned power system stabilizer (PSS1A) can cope with large disturbance at different operating points and has enhanced power system stability.Keywords: Static excitation system, particle swarm optimization (PSO), power system stabilizer (PSS).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2418537 A Double PWM Source Inverter Technique with Reduced Leakage Current for Application on Standalone Systems
Authors: Md. Noman Habib Khan, S. Khan, T. S. Gunawan, R. I. Boby
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The photovoltaic (PV) panel with no galvanic isolation system is well known technique in the world which is effective and delivers power with enhanced efficiency. The PV generation presented here is for stand-alone system installed in remote areas when as the resulting power gets connected to electronic load installation instead of being tied to the grid. Though very small, even then transformer-less topology is shown to be with leakage in pico-ampere range. By using PWM technique PWM, leakage current in different situations is shown. The results shown in this paper show how the pico-ampere current is reduced to femto-ampere through use of inductors and capacitors of suitable values of inductor and capacitors with the load.Keywords: Photovoltaic (PV) panel, Duty cycle, Pulse Duration Modulation (PDM), Leakage current.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1451536 The Effect of Type of Nanoparticles on the Quenching Process
Authors: Dogan Ciloglu, Abdurrahim Bolukbasi, Harun Cifci
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In this study, the experiments were carried out to determine the best coolant for the quenching process among waterbased silica, alumina, titania and copper oxide nanofluids (0.1 vol%). A sphere made up off brass material was used in the experiments. When the spherical test specimen was heated at high temperatures, it was suddenly immersed into the nanofluids. All experiments were carried out at saturated conditions and under atmospheric pressure. After the experiments, the cooling curves were obtained by using the temperature-time data of the specimen. The experimental results showed that the cooling performance of test specimen depended on the type of nanofluids. The silica nanoparticles enhanced the performance of boiling heat transfer and it is the best coolant for the quenching among other nanoparticles.Keywords: Heat transfer, nanofluid, pool boiling, quenching.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2596535 Simulation Study of Lateral Trench Gate Power MOSFET on 4H-SiC
Authors: Yashvir Singh, Mayank Joshi
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A lateral trench-gate power metal-oxide-semiconductor on 4H-SiC is proposed. The device consists of two separate trenches in which two gates are placed on both sides of P-body region resulting two parallel channels. Enhanced current conduction and reduced-surface-field effect in the structure provide substantial improvement in the device performance. Using two dimensional simulations, the performance of proposed device is evaluated and compare of with that of the conventional device for same cell pitch. It is demonstrated that the proposed structure provides two times higher output current, 11% decrease in threshold voltage, 70% improvement in transconductance, 70% reduction in specific ON-resistance, 52% increase in breakdown voltage, and nearly eight time improvement in figure-of-merit over the conventional device.
Keywords: 4H-SiC, lateral, trench-gate, power MOSFET.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2130534 Object Alignment for Military Optical Surveillance
Authors: Oscar J.G. Somsen, Fok Bolderheij
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Electro-optical devices are increasingly used for military sea-, land- and air applications to detect, recognize and track objects. Typically, these devices produce video information that is presented to an operator. However, with increasing availability of electro-optical devices the data volume is becoming very large, creating a rising need for automated analysis. In a military setting, this typically involves detecting and recognizing objects at a large distance, i.e. when they are difficult to distinguish from background and noise. One may consider combining multiple images from a video stream into a single enhanced image that provides more information for the operator. In this paper we investigate a simple algorithm to enhance simulated images from a military context and investigate how the enhancement is affected by various types of disturbance.Keywords: Electro-Optics, Automated Image alignment
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1603