Search results for: maximum power point tracking (MPPT).
2697 Sensitizing Rules for Fuzzy Control Charts
Authors: N. Pekin Alakoç, A. Apaydın
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Quality control charts indicate out of control conditions if any nonrandom pattern of the points is observed or any point is plotted beyond the control limits. Nonrandom patterns of Shewhart control charts are tested with sensitizing rules. When the processes are defined with fuzzy set theory, traditional sensitizing rules are insufficient for defining all out of control conditions. This is due to the fact that fuzzy numbers increase the number of out of control conditions. The purpose of the study is to develop a set of fuzzy sensitizing rules, which increase the flexibility and sensitivity of fuzzy control charts. Fuzzy sensitizing rules simplify the identification of out of control situations that results in a decrease in the calculation time and number of evaluations in fuzzy control chart approach.Keywords: Fuzzy set theory, Quality control charts, Run Rules, Unnatural patterns.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 35422696 A Pilot Study for the Optimization of Routes for Waste Collection Vehicles for the Göçmenköy District of Lefkoşa
Authors: Nergiz Fırıncı, Aysun Çelik, Ertan Akün, Md. Atif Khan
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A pilot project was carried out in 2007 by the senior students of Cyprus International University, aiming to minimize the total cost of waste collection in Northern Cyprus. Many developed and developing countries have cut their transportation costs – which lies between 30-40% – down at a rate of 40% percent, by implementing network models for their route assignments. Accordingly, a network model was implemented at Göçmenköy district, to optimize and standardize waste collection works. The work environment of the employees were also redesigned to provide maximum ergonomy and to increase productivity, efficiency and safety. Following the collection of the required data including waste densities, lengths of roads and population, a model was constructed to allocate the optimal route assignment for the waste collection trucks at Göçmenköy district.Keywords: Minimization, waste collection, operations cost, transportation, ergonomy, productivity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26682695 Empirical Study on Causes of Project Delays
Authors: Khan Farhan Rafat, Riaz Ahmed
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Renowned offshore organizations are drifting towards collaborative exertion to win and implement international projects for business gains. However, devoid of financial constraints, with the availability of skilled professionals, and despite improved project management practices through state-of-the-art tools and techniques, project delays have become a norm these days. This situation calls for exploring the factor(s) affecting the bonding between project management performance and project success. In the context of the well-known 3M’s of project management (that is, manpower, machinery, and materials), machinery and materials are dependent upon manpower. Because the body of knowledge inveterate on the influence of national culture on men, hence, the realization of the impact on the link between project management performance and project success need to be investigated in detail to arrive at the possible cause(s) of project delays. This research initiative was, therefore, undertaken to fill the research gap. The unit of analysis for the proposed research excretion was the individuals who had worked on skyscraper construction projects. In reverent studies, project management is best described using construction examples. It is due to this reason that the project oriented city of Dubai was chosen to reconnoiter on causes of project delays. A structured questionnaire survey was disseminated online with the courtesy of the Project Management Institute local chapter to carry out the cross-sectional study. The Construction Industry Institute, Austin, of the United States of America along with 23 high-rise builders in Dubai were also contacted by email requesting for their contribution to the study and providing them with the online link to the survey questionnaire. The reliability of the instrument was warranted using Cronbach’s alpha coefficient of 0.70. The appropriateness of sampling adequacy and homogeneity in variance was ensured by keeping Kaiser–Meyer–Olkin (KMO) and Bartlett’s test of sphericity in the range ≥ 0.60 and < 0.05, respectively. Factor analysis was used to verify construct validity. During exploratory factor analysis, all items were loaded using a threshold of 0.4. Four hundred and seventeen respondents, including members from top management, project managers, and project staff, contributed to the study. The link between project management performance and project success was significant at 0.01 level (2-tailed), and 0.05 level (2-tailed) for Pearson’s correlation. Before initiating the moderator analysis test for linearity, multicollinearity, outliers, leverage points and influential cases, test for homoscedasticity and normality were carried out which are prerequisites for conducting moderator review. The moderator analysis, using a macro named PROCESS, was performed to verify the hypothesis that national culture has an influence on the said link. The empirical findings, when compared with Hofstede's results, showed high power distance as the cause of construction project delays in Dubai. The research outcome calls for the project sponsors and top management to reshape their project management strategy and allow for low power distance between management and project personnel for timely completion of projects.Keywords: Causes of construction project delays, construction industry, construction management, power distance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 31202694 Earth Potential Rise (EPR) Computation for a Fault on Transmission Mains Pole
Authors: M. Nassereddine, J. Rizk, A. Hellany, M. Nagrial
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The prologue of new High Voltage (HV) transmission mains into the community necessitates earthing design to ensure safety compliance of the system. Conductive structures such as steel or concrete poles are widely used in HV transmission mains. The earth potential rise (EPR) generated by a fault on these structures could result to an unsafe condition. This paper discusses information on the input impedance of the over head earth wire (OHEW) system for finite and infinite transmission mains. The definition of finite and infinite system is discussed, maximum EPR due to pole fault. The simplified equations for EPR assessments are introduced and discussed for the finite and infinite conditions. A case study is also shown.Keywords: Coupling Factor, Earth Grid, EPR, Fault Current Distribution, High Voltage, Line Impedance, OHEW, Split Factor, Transmission Mains.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 38312693 Optimizing the Project Delivery Time with Time Cost Trade-offs
Authors: Wei Lo, Ming-En Kuo
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While to minimize the overall project cost is always one of the objectives of construction managers, to obtain the maximum economic return is definitely one the ultimate goals of the project investors. As there is a trade-off relationship between the project time and cost, and the project delivery time directly affects the timing of economic recovery of an investment project, to provide a method that can quantify the relationship between the project delivery time and cost, and identify the optimal delivery time to maximize economic return has always been the focus of researchers and industrial practitioners. Using genetic algorithms, this study introduces an optimization model that can quantify the relationship between the project delivery time and cost and furthermore, determine the optimal delivery time to maximize the economic return of the project. The results provide objective quantification for accurately evaluating the project delivery time and cost, and facilitate the analysis of the economic return of a project.Keywords: Time-Cost Trade-Off, Genetic Algorithms, Resource Integration, Economic return.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17742692 Glutamic Acid Production from Potato by Brevibacterium linens
Authors: Marzieh Moosavi-Nasab, Masoumeh Izadi, Sara Hosseinpour
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In this study, the possibility of using potato as a substrate for glutamic acid production by Brevibacterium linens was investigated. For preparation of fermentation medium, potato was hydrolyzed by hydrochloridric acid. The medium contained potato hydrolysate, tween 80, mineral solution, glucose, and potassium hydrogen phosphate. The initial pH of the medium was adjusted to 7-7.5. For achieving the optimum time with maximum yield, the beakers containing the medium and the inoculums were incubated in a rotary water bath flask shaker for one to five days. Thin layer choromatography was used for quantitative and qualitative assay of the glutamic acid produced. The results revealed that as fermentation time increased, pH of the fermentation medium significantly decreased (P<0.05). Furthermore, glutamic acid concentration in fermentation medium increased significantly (P<0.05). The highest amount of the glutamic acid obtained was 5.6 g/l on the forth day of fermentation.Keywords: Brevibacterium linens, Fermentation, Glutamicacid, Thin layer choromatography
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25652691 Assessment of Procurement-Demand of Milk Plant Using Quality Control Tools: A Case Study
Authors: Jagdeep Singh, Prem Singh
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Milk is considered as an essential and complete food. The present study was conducted at Milk Plant Mohali especially in reference to the procurement section where the cash inflow was maximum, with the objective to achieve higher productivity and reduce wastage of milk. In milk plant it was observed that during the month of Jan-2014 to March-2014 the average procurement of milk was Rs. 4, 19, 361 liter per month and cost of procurement of milk is Rs 35/- per liter. The total cost of procurement thereby equal to Rs. 1crore 46 lakh per month, but there was mismatch in procurementproduction of milk, which leads to an average loss of Rs. 12, 94, 405 per month. To solve the procurement-production problem Quality Control Tools like brainstorming, Flow Chart, Cause effect diagram and Pareto analysis are applied wherever applicable. With the successful implementation of Quality Control tools an average saving of Rs. 4, 59, 445 per month is done.Keywords: Milk, Procurement-demand, quality control tools.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28842690 Lineup Optimization Model of Basketball Players Based on the Prediction of Recursive Neural Networks
Authors: Wang Yichen, Haruka Yamashita
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In recent years, in the field of sports, decision making such as member in the game and strategy of the game based on then analysis of the accumulated sports data are widely attempted. In fact, in the NBA basketball league where the world's highest level players gather, to win the games, teams analyze the data using various statistical techniques. However, it is difficult to analyze the game data for each play such as the ball tracking or motion of the players in the game, because the situation of the game changes rapidly, and the structure of the data should be complicated. Therefore, it is considered that the analysis method for real time game play data is proposed. In this research, we propose an analytical model for "determining the optimal lineup composition" using the real time play data, which is considered to be difficult for all coaches. In this study, because replacing the entire lineup is too complicated, and the actual question for the replacement of players is "whether or not the lineup should be changed", and “whether or not Small Ball lineup is adopted”. Therefore, we propose an analytical model for the optimal player selection problem based on Small Ball lineups. In basketball, we can accumulate scoring data for each play, which indicates a player's contribution to the game, and the scoring data can be considered as a time series data. In order to compare the importance of players in different situations and lineups, we combine RNN (Recurrent Neural Network) model, which can analyze time series data, and NN (Neural Network) model, which can analyze the situation on the field, to build the prediction model of score. This model is capable to identify the current optimal lineup for different situations. In this research, we collected all the data of accumulated data of NBA from 2019-2020. Then we apply the method to the actual basketball play data to verify the reliability of the proposed model.Keywords: Recurrent Neural Network, players lineup, basketball data, decision making model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8292689 Open Channel Flow Measurement of Water by Using Width Contraction
Authors: Arun Goel, D. V. S. Verma, Sanjeev Sangwan
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Present study was aimed to develop a discharge measuring device for irrigation and laboratory channels. Experiments were conducted on sharp edged constricted flow meters having four types of width constrictions namely 2:1, 1.5:1, 1:1 and 90o in the direction of flow. These devices were made of MS sheets and installed separately in a rectangular flume. All these four devices were tested under free and submerged flow conditions. Eight different discharges varying from 2 lit/sec to 30 lit/sec were passed through each device. In total around 500 observations of upstream and downstream depths were taken in the present work. For each discharge, free submerged and critical submergence under different flow conditions were noted and plotted. Once the upstream and downstream depths of flow over any of the device are known, the discharge can be easily calculated with the help of the curves developed for free and submerged flow conditions. The device having contraction 2:1 is the most efficient one as it allows maximum critical submergence.Keywords: Flowrate, flowmeter, open channels, submergence.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23222688 Integral Domains and Their Algebras: Topological Aspects
Authors: Shai Sarussi
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Let S be an integral domain with field of fractions F and let A be an F-algebra. An S-subalgebra R of A is called S-nice if R∩F = S and the localization of R with respect to S \{0} is A. Denoting by W the set of all S-nice subalgebras of A, and defining a notion of open sets on W, one can view W as a T0-Alexandroff space. Thus, the algebraic structure of W can be viewed from the point of view of topology. It is shown that every nonempty open subset of W has a maximal element in it, which is also a maximal element of W. Moreover, a supremum of an irreducible subset of W always exists. As a notable connection with valuation theory, one considers the case in which S is a valuation domain and A is an algebraic field extension of F; if S is indecomposed in A, then W is an irreducible topological space, and W contains a greatest element.Keywords: Algebras over integral domains, Alexandroff topology, valuation domains, integral domains.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5072687 Functionalized PU Foam for Water Filtration
Authors: Nidal H. Abu-Zahra, Subhashini Gunashekar
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Polyurethane foam is functionalized with Sulfonic acid groups to remove lead ions (Pb2+) from drinking water through a cation exchange process. The synthesis is based on addition polymerization of the -NCO groups of an isocyanate with the –OH groups of a polyol to form the urethane. Toluene-diisocyanateis reacted with Polypropylene glycol to form a linear pre-polymer, which is further polymerized using a chain extender, N, N-bis(2-hydorxyethyl)-2-aminoethane-sulfonic acid (BES). BES acts as a functional group site to exchange Pb2+ ions. A set of experiments was designed to study the effect of various processing parameters on the performance of the synthesized foam. The maximum Pb2+ ion exchange capacity of the foam was found to be 47ppb/g from a 100ppb Pb2+ solution over a period of 60 minutes. A multistage batch filtration process increased the lead removal to 50-54ppb/3g of foam over a period of 90 minutes.
Keywords: Adsorption, Functionalized, Ion exchange, Polyurethane, Sulfonic.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30962686 Security Weaknesses of Dynamic ID-based Remote User Authentication Protocol
Authors: Hyoungseob Lee, Donghyun Choi, Yunho Lee, Dongho Won, Seungjoo Kim
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Recently, with the appearance of smart cards, many user authentication protocols using smart card have been proposed to mitigate the vulnerabilities in user authentication process. In 2004, Das et al. proposed a ID-based user authentication protocol that is secure against ID-theft and replay attack using smart card. In 2009, Wang et al. showed that Das et al.-s protocol is not secure to randomly chosen password attack and impersonation attack, and proposed an improved protocol. Their protocol provided mutual authentication and efficient password management. In this paper, we analyze the security weaknesses and point out the vulnerabilities of Wang et al.-s protocol.Keywords: Message Alteration Attack, Impersonation Attack
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17732685 Effect of Silver Nanoparticles Size Prepared by Photoreduction Method on Optical Absorption Spectra of TiO2/Ag/N719 Dye Composite Films
Authors: C. Photiphitak, P. Rakkwamsuk, P. Muthitamongkol, C. Sae-Kung, C. Thanachayanont
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TiO2/Ag composite films were prepared by incorporating Ag in the pores of mesoporous TiO2 films using a photoreduction method. The Ag nanoparticle sizes were in a range of 3.66-38.56 nm. The TiO2/Ag composite films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscropy (TEM). The TiO2 films and TiO2/Ag composite films were immersed in a 0.3 mM N719 dye solution and characterized by UV-Vis spectrophotometer. The TiO2/Ag/N719 composite film showed that an optimal size of Ag nanoparticles was 19.12 nm and, hence, gave the maximum optical absorption spectra. The improved absorption was due to surface plasmon resonance induced by the Ag nanoparticles to enhance the absorption coefficient of the dye.Keywords: Silver nanoparticle, TiO2/Ag composite films, Optical properties, surface plasmon resonance
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26032684 Influence of High Temperature and Humidity on Polymer Composites Used in Relining of Sewage
Authors: Parastou Kharazmi, Folke Björk
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Some of the main causes for degradation of polymeric materials are thermal aging, hydrolysis, oxidation or chemical degradation by acids, alkalis or water. The first part of this paper provides a brief summary of advances in technology, methods and specification of composite materials for relining as a rehabilitation technique for sewage systems. The second part summarizes an investigation on frequently used composite materials for relining in Sweden, the rubber filled epoxy composite and reinforced polyester composite when they were immersed in deionized water or in dry conditions, and elevated temperatures up to 80°C in the laboratory. The tests were conducted by visual inspection, microscopy, Dynamic Mechanical Analysis (DMA), Differential Scanning Calorimetry (DSC) as well as mechanical testing, three point bending and tensile testing.
Keywords: Composite, epoxy, polyester, relining, sewage.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17022683 Preparation and Characterization of Photocatalyst for the Conversion of Carbon Dioxide to Methanol
Authors: D. M. Reddy Prasad, Nur Sabrina Binti Rahmat, Huei Ruey Ong, Chin Kui Cheng, Maksudur Rahman Khan, D. Sathiyamoorthy
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Carbon dioxide (CO2) emission to the environment is inevitable which is responsible for global warming. Photocatalytic reduction of CO2 to fuel, such as methanol, methane etc. is a promising way to reduce greenhouse gas CO2 emission. In the present work, Bi2S3/CdS was synthesized as an effective visible light responsive photocatalyst for CO2 reduction into methanol. The Bi2S3/CdS photocatalyst was prepared by hydrothermal reaction. The catalyst was characterized by X-ray diffraction (XRD) instrument. The photocatalytic activity of the catalyst has been investigated for methanol production as a function of time. Gas chromatograph flame ionization detector (GC-FID) was employed to analyze the product. The yield of methanol was found to increase with higher CdS concentration in Bi2S3/CdS and the maximum yield was obtained for 45 wt% of Bi2S3/CdS under visible light irradiation was 20 μmole/g. The result establishes that Bi2S3/CdS is favorable catalyst to reduce CO2 to methanol.
Keywords: Photocatalyst, Carbon dioxide reduction, visible light, Irradiation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20322682 An Adaptive ARQ – HARQ Method with Two RS Codes
Authors: Michal Martinovič, Jaroslav Polec, Kvetoslava Kotuliaková
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In this paper we proposed multistage adaptive ARQ/HARQ/HARQ scheme. This method combines pure ARQ (Automatic Repeat reQuest) mode in low channel bit error rate and hybrid ARQ method using two different Reed-Solomon codes in middle and high error rate conditions. It follows, that our scheme has three stages. The main goal is to increase number of states in adaptive HARQ methods and be able to achieve maximum throughput for every channel bit error rate. We will prove the proposal by calculation and then with simulations in land mobile satellite channel environment. Optimization of scheme system parameters is described in order to maximize the throughput in the whole defined Signal-to- Noise Ratio (SNR) range in selected channel environment.Keywords: Signal-to-noise ratio, throughput, forward error correction (FEC), pure and hybrid automatic repeat request (ARQ).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19682681 Haar Wavelet Method for Solving Fitz Hugh-Nagumo Equation
Authors: G.Hariharan, K.Kannan
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In this paper, we develop an accurate and efficient Haar wavelet method for well-known FitzHugh-Nagumo equation. The proposed scheme can be used to a wide class of nonlinear reaction-diffusion equations. The power of this manageable method is confirmed. Moreover the use of Haar wavelets is found to be accurate, simple, fast, flexible, convenient, small computation costs and computationally attractive.
Keywords: FitzHugh-Nagumo equation, Haar wavelet method, adomain decomposition method, computationally attractive.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27812680 Bootstrap and MLS Methods-based Individual Bioequivalence Assessment
Authors: Kongsheng Zhang, Li Ge
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It is a one-sided hypothesis testing process for assessing bioequivalence. Bootstrap and modified large-sample(MLS) methods are considered to study individual bioequivalence(IBE), type I error and power of hypothesis tests are simulated and compared with FDA(2001). The results show that modified large-sample method is equivalent to the method of FDA(2001) .
Keywords: Individual bioequivalence, bootstrap, Bayesian bootstrap, modified large-sample.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15842679 Objective Performance of Compressed Image Quality Assessments
Authors: Ratchakit Sakuldee, Somkait Udomhunsakul
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Measurement of the quality of image compression is important for image processing application. In this paper, we propose an objective image quality assessment to measure the quality of gray scale compressed image, which is correlation well with subjective quality measurement (MOS) and least time taken. The new objective image quality measurement is developed from a few fundamental of objective measurements to evaluate the compressed image quality based on JPEG and JPEG2000. The reliability between each fundamental objective measurement and subjective measurement (MOS) is found. From the experimental results, we found that the Maximum Difference measurement (MD) and a new proposed measurement, Structural Content Laplacian Mean Square Error (SCLMSE), are the suitable measurements that can be used to evaluate the quality of JPEG200 and JPEG compressed image, respectively. In addition, MD and SCLMSE measurements are scaled to make them equivalent to MOS, given the rate of compressed image quality from 1 to 5 (unacceptable to excellent quality).
Keywords: JPEG, JPEG2000, objective image quality measurement, subjective image quality measurement, correlation coefficients.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21882678 Reducing Sugar Production from Durian Peel by Hydrochloric Acid Hydrolysis
Authors: Matura Unhasirikul, Nuanphan Naranong, Woatthichai Narkrugsa
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Agricultural waste is mainly composed of cellulose and hemicelluloses which can be converted to sugars. The inexpensive reducing sugar from durian peel was obtained by hydrolysis with HCl concentration at 0.5-2.0% (v/v). The hydrolysis range of time was for 15-60 min when the mixture was autoclaved at 121 °C. The result showed that acid hydrolysis efficiency (AHE) highest to 80.99% at condition is 2.0%concentration for 15 min. Reducing sugar highest to 56.07 g/litre at condition is 2.0% concentration for 45min. Total sugar highest to 59.83 g/litre at condition is 2.0%concentration for 45min, which was not significant (p < 0.05) with condition 2.0% concentration for 30 min and 1.5 % concentration for 45 and 60 min. The increase in concentration increased AHE, reducing sugar and total sugar. The hydrolysis time had no effect on AHE, reducing sugar and total sugar. The maximum reducing sugars of each concentration were at hydrolysis time 45 min .The hydrolysated were analysis by HPLC, the results revealed that the principle of sugar were glucose, fructose and xylose.Keywords: acid hydrolysis efficiency (AHE), reducing sugar, total sugar
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32602677 Milling Simulations with a 3-DOF Flexible Planar Robot
Authors: Hoai Nam Huynh, Edouard Rivière-Lorphèvre, Olivier Verlinden
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Manufacturing technologies are becoming continuously more diversified over the years. The increasing use of robots for various applications such as assembling, painting, welding has also affected the field of machining. Machining robots can deal with larger workspaces than conventional machine-tools at a lower cost and thus represent a very promising alternative for machining applications. Furthermore, their inherent structure ensures them a great flexibility of motion to reach any location on the workpiece with the desired orientation. Nevertheless, machining robots suffer from a lack of stiffness at their joints restricting their use to applications involving low cutting forces especially finishing operations. Vibratory instabilities may also happen while machining and deteriorate the precision leading to scrap parts. Some researchers are therefore concerned with the identification of optimal parameters in robotic machining. This paper continues the development of a virtual robotic machining simulator in order to find optimized cutting parameters in terms of depth of cut or feed per tooth for example. The simulation environment combines an in-house milling routine (DyStaMill) achieving the computation of cutting forces and material removal with an in-house multibody library (EasyDyn) which is used to build a dynamic model of a 3-DOF planar robot with flexible links. The position of the robot end-effector submitted to milling forces is controlled through an inverse kinematics scheme while controlling the position of its joints separately. Each joint is actuated through a servomotor for which the transfer function has been computed in order to tune the corresponding controller. The output results feature the evolution of the cutting forces when the robot structure is deformable or not and the tracking errors of the end-effector. Illustrations of the resulting machined surfaces are also presented. The consideration of the links flexibility has highlighted an increase of the cutting forces magnitude. This proof of concept will aim to enrich the database of results in robotic machining for potential improvements in production.Keywords: Control, machining, multibody, robotic, simulation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13672676 Preparation of Metallic Copper Nanoparticles by Reduction of Copper Ions in Aqueous Solution and Their Metal-Metal Bonding Properties
Authors: Y. Kobayashi, T. Shirochi, Y. Yasuda, T. Morita
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This paper describes a method for preparing metallic Cu nanoparticles in aqueous solution, and a metal-metal bonding technique using the Cu particles.Preparation of the Cu particle colloid solution was performed in water at room temperature in air using a copper source (0.01 M Cu(NO3)2), a reducing reagent (0.2 - 1.0 M hydrazine), and stabilizers (0.5×10-3 M citric acid and 5.0×10-3 M cetyltrimethylammonium bromide). The metallic Cu nanoparticles with sizes of ca. 60nm were prepared at all the hydrazine concentrations examined. A stage and a plate of metallic Cu were successfully bonded under annealing at 400oC and pressurizing at 1.2 MPa for 5min in H2 gas with help of the metallic Cu particles. A shear strength required for separating the bonded Cu substrates reached the maximum value at a hydrazine concentration of 0.8M, and it decreased beyond the concentration. Consequently, the largest shear strength of 22.9 MPa was achieved at the 0.8 M hydrazine concentration.
Keywords: Aqueous solution, Bonding, Colloid, Copper, Nanoparticle.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 56572675 A Dynamically Reconfigurable Arithmetic Circuit for Complex Number and Double Precision Number
Authors: Haruo Shimada, Akinori Kanasugi
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This paper proposes an architecture of dynamically reconfigurable arithmetic circuit. Dynamic reconfiguration is a technique to realize required functions by changing hardware construction during operations. The proposed circuit is based on a complex number multiply-accumulation circuit which is used frequently in the field of digital signal processing. In addition, the proposed circuit performs real number double precision arithmetic operations. The data formats are single and double precision floating point number based on IEEE754. The proposed circuit is designed using VHDL, and verified the correct operation by simulations and experiments.Keywords: arithmetic circuit, complex number, double precision, dynamic reconfiguration
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15622674 Ruin Probability for a Markovian Risk Model with Two-type Claims
Authors: Dongdong Zhang, Deran Zhang
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In this paper, a Markovian risk model with two-type claims is considered. In such a risk model, the occurrences of the two type claims are described by two point processes {Ni(t), t ¸ 0}, i = 1, 2, where {Ni(t), t ¸ 0} is the number of jumps during the interval (0, t] for the Markov jump process {Xi(t), t ¸ 0} . The ruin probability ª(u) of a company facing such a risk model is mainly discussed. An integral equation satisfied by the ruin probability ª(u) is obtained and the bounds for the convergence rate of the ruin probability ª(u) are given by using key-renewal theorem.
Keywords: Risk model, ruin probability, Markov jump process, integral equation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13662673 Recognition of Grocery Products in Images Captured by Cellular Phones
Authors: Farshideh Einsele, Hassan Foroosh
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In this paper, we present a robust algorithm to recognize extracted text from grocery product images captured by mobile phone cameras. Recognition of such text is challenging since text in grocery product images varies in its size, orientation, style, illumination, and can suffer from perspective distortion. Pre-processing is performed to make the characters scale and rotation invariant. Since text degradations can not be appropriately defined using well-known geometric transformations such as translation, rotation, affine transformation and shearing, we use the whole character black pixels as our feature vector. Classification is performed with minimum distance classifier using the maximum likelihood criterion, which delivers very promising Character Recognition Rate (CRR) of 89%. We achieve considerably higher Word Recognition Rate (WRR) of 99% when using lower level linguistic knowledge about product words during the recognition process.
Keywords: Camera-based OCR, Feature extraction, Document and image processing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24702672 Dynamic Analysis of Offshore 2-HUS/U Parallel Platform
Authors: Xie Kefeng, Zhang He
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For the stability and control demand of offshore small floating platform, a 2-HUS/U parallel mechanism was presented as offshore platform. Inverse kinematics was obtained by institutional constraint equation, and the dynamic model of offshore 2-HUS/U parallel platform was derived based on rigid body’s Lagrangian method. The equivalent moment of inertia, damping and driving force/torque variation of offshore 2-HUS/U parallel platform were analyzed. A numerical example shows that, for parallel platform of given motion, system’s equivalent inertia changes 1.25 times maximally. During the movement of platform, they change dramatically with the system configuration and have coupling characteristics. The maximum equivalent drive torque is 800 N. At the same time, the curve of platform’s driving force/torque is smooth and has good sine features. The control system needs to be adjusted according to kinetic equation during stability and control and it provides a basis for the optimization of control system.Keywords: 2-HUS/U platform, Dynamics, Lagrange, Parallel platform.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9722671 Thermal and Flammability Properties of Paraffin/Nanoclay Composite Phase Change Materials Incorporated in Building Materials for Thermal Energy Storage
Authors: Awni H. Alkhazaleh, Baljinder K. Kandola
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In this study, a form-stable composite Paraffin/Nanoclay (PA-NC) has been prepared by absorbing PA into porous particles of NC to be used for low-temperature latent heat thermal energy storage. The leakage test shows that the maximum mass fraction of PA that can be incorporated in NC without leakage is 60 wt.%. Differential scanning calorimetry (DSC) has been used to measure the thermal properties of the PA and PA-NC both before and after incorporation in plasterboard (PL). The mechanical performance of the samples has been evaluated in flexural mode. The thermal energy storage performance has been studied using a small test chamber (100 mm × 100 mm × 100 mm) made from 10 mm thick PL and measuring the temperatures using thermocouples. The flammability of the PL+PL-NC has been discussed using a cone calorimeter. The results indicate that the form composite PA has good potential for use as thermal energy storage materials in building applications.
Keywords: Flammability, paraffin, plasterboard, thermal energy storage.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10382670 Limit State of Heterogeneous Smart Structures under Unknown Cyclic Loading
Authors: M. Chen, S-Q. Zhang, X. Wang, D. Tate
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This paper presents a numerical solution, namely limit and shakedown analysis, to predict the safety state of smart structures made of heterogeneous materials under unknown cyclic loadings, for instance, the flexure hinge in the micro-positioning stage driven by piezoelectric actuator. In combination of homogenization theory and finite-element method (FEM), the safety evaluation problem is converted to a large-scale nonlinear optimization programming for an acceptable bounded loading as the design reference. Furthermore, a general numerical scheme integrated with the FEM and interior-point-algorithm based optimization tool is developed, which makes the practical application possible.
Keywords: Limit state, shakedown analysis, homogenization, heterogeneous structure.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8502669 Adsorption of Ferrous and Ferric Ions in Aqueous and Industrial Effluent onto Pongamia pinnata Tree Bark
Authors: M. Mamatha, H. B. Aravinda, E. T. Puttaiah, S. Manjappa
Abstract:
One of the causes of water pollution is the presence of heavy metals in water. In the present study, an adsorbent prepared from the raw bark of the Pongamia pinnata tree is used for the removal of ferrous or ferric ions from aqueous and waste water containing heavy metals. Adsorption studies were conducted at different pH, concentration of metal ion, amount of adsorbent, contact time, agitation and temperature. The Langmuir and Freundlich adsorption isotherm models were applied for the results. The Langmuir isotherms were best fitted by the equilibrium data. The maximum adsorption was found to 146mg/g in waste water at a temperature of 30°C which is in agreement as comparable to the adsorption capacity of different adsorbents reported in literature. Pseudo second order model best fitted the adsorption of both ferrous and ferric ions.
Keywords: Adsorption, Adsorption isotherms, Heavy metals, Industrial effluents.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32512668 Compact Er3+-Doped ZBLAN Green Upconversion Fibre Laser
Authors: Syed Sohail Abbas, Sergei Popov
Abstract:
In this paper, a fibre laser at 546 nm has been studied for a signal power of -30 dB. Er3+-doped ZBLAN fibre has been used by upconversion pumping of a 980 nm laser diode. Gain saturation effect has been investigated in detail. Laser performance has also been discussed. An efficiency of 35% has been calculated with a length of 5 mm fibre laser. Results show that Er3+-doped ZBLAN is a promising candidate for optical amplification at 546 nm.Keywords: Compact visible lasers, Erbium doped, Gainsaturation, Green laser, Optical fibre lasers
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