Search results for: physical properties.
1632 A Method for Modeling Multiple Antenna Channels
Authors: S. Rajabi, M. ArdebiliPoor, M. Shahabadi
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In this paper we propose a method for modeling the correlation between the received signals by two or more antennas operating in a multipath environment. Considering the maximum excess delay in the channel being modeled, an elliptical region surrounding both transmitter and receiver antennas is produced. A number of scatterers are randomly distributed in this region and scatter the incoming waves. The amplitude and phase of incoming waves are computed and used to obtain statistical properties of the received signals. This model has the distinguishable advantage of being applicable for any configuration of antennas. Furthermore the common PDF (Probability Distribution Function) of received wave amplitudes for any pair of antennas can be calculated and used to produce statistical parameters of received signals.Keywords: MIMO (Multiple Input Multiple Output), SIMO (Single Input Multiple Output), GBSBEM (Geometrically Based Single Bounce Elliptical Model).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14271631 Enhanced Weighted Centroid Localization Algorithm for Indoor Environments
Authors: I. Nižetić Kosović, T. Jagušt
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Lately, with the increasing number of location-based applications, demand for highly accurate and reliable indoor localization became urgent. This is a challenging problem, due to the measurement variance which is the consequence of various factors like obstacles, equipment properties and environmental changes in complex nature of indoor environments. In this paper we propose low-cost custom-setup infrastructure solution and localization algorithm based on the Weighted Centroid Localization (WCL) method. Localization accuracy is increased by several enhancements: calibration of RSSI values gained from wireless nodes, repetitive measurements of RSSI to exclude deviating values from the position estimation, and by considering orientation of the device according to the wireless nodes. We conducted several experiments to evaluate the proposed algorithm. High accuracy of ~1m was achieved.
Keywords: Indoor environment, received signal strength indicator, weighted centroid localization, wireless localization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 31081630 The Experience of Iranian Architecture in Direction of Urban Passages and Forming of Urban Structures to Increase Climatic Comfort
Authors: N. Utaberta, N. Sharifi, M. Surat, A. I. Che-Ani, N.M. Tawil
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Iran has diverse climates and each have established distinct properties in their area. The extent and intensity of climatic factors effects on the lives of people living in various regions of Iran is so great that it cannot be simply ignored. In a large part of Iran known as the Central Plateau there is no precipitation for more than half of the year and dry weather and scarcity of fresh water pose an ever present problem for the people of these regions while in north of Iran upon the southern shores of the Caspian Sea the people face 80% humidity caused by the sea and 2 meters of annual precipitation. This article tries to review the past experiences of local architecture of Iran-s various regions so that they can be used to reshape and redirect the urban areas and structure of Iran-s current cities to provide environmental comfort by minimum use of fossil fuels.
Keywords: Urban Passage, Architecture in Iran, Urban Structure, Climatic Comfort
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16301629 Digital Homeostasis: Tangible Computing as a Multi-Sensory Installation
Authors: Andrea Macruz
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This paper explores computation as a process for design by examining how computers can become more than an operative strategy in a designer's toolkit. It documents this, building upon concepts of neuroscience and Antonio Damasio's Homeostasis Theory, which is the control of bodily states through feedback intended to keep conditions favorable for life. To do this, it follows a methodology through algorithmic drawing and discusses the outcomes of three multi-sensory design installations, which culminated from a course in an academic setting. It explains both the studio process that took place to create the installations and the computational process that was developed, related to the fields of algorithmic design and tangible computing. It discusses how designers can use computational range to achieve homeostasis related to sensory data in a multi-sensory installation. The outcomes show clearly how people and computers interact with different sensory modalities and affordances. They propose using computers as meta-physical stabilizers rather than tools.
Keywords: Antonio Damasio, emotional feedback, algorithmic drawing, homeostasis, multi-sensory installation, neuroscience.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3781628 Testing of Materials for Rapid Prototyping Fused Deposition Modelling Technology
Authors: L. Novakova-Marcincinova, J. Novak-Marcincin
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Paper presents knowledge about types of test in area of materials properties of selected methods of rapid prototyping technologies. In today used rapid prototyping technologies for production of models and final parts are used materials in initial state as solid, liquid or powder material structure. In solid state are used various forms such as pellets, wire or laminates. Basic range materials include paper, nylon, wax, resins, metals and ceramics. In Fused Deposition Modeling (FDM) rapid prototyping technology are mainly used as basic materials ABS (Acrylonitrile Butadiene Styrene), polyamide, polycarbonate, polyethylene and polypropylene. For advanced FDM applications are used special materials as silicon nitrate, PZT (Piezoceramic Material - Lead Zirconate Titanate), aluminium oxide, hydroxypatite and stainless steel.Keywords: Rapid prototyping, materials, testing of materials.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 44471627 Vision-based Network System for Industrial Applications
Authors: Taweepol Suesut, Arjin Numsomran, Vittaya Tipsuwanporn
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This paper presents the communication network for machine vision system to implement to control systems and logistics applications in industrial environment. The real-time distributed over the network is very important for communication among vision node, image processing and control as well as the distributed I/O node. A robust implementation both with respect to camera packaging and data transmission has been accounted. This network consists of a gigabit Ethernet network and a switch with integrated fire-wall is used to distribute the data and provide connection to the imaging control station and IEC-61131 conform signal integration comprising the Modbus TCP protocol. The real-time and delay time properties each part on the network were considered and worked out in this paper.Keywords: Distributed Real-Time Automation, Machine Visionand Ethernet.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16711626 Modified Diffie-Hellman Protocol By Extend The Theory of The Congruence
Authors: Rand Alfaris, Mohamed Rushdan MD Said, Mohamed Othman, Fudziah Ismail
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This paper is introduced a modification to Diffie- Hellman protocol to be applicable on the decimal numbers, which they are the numbers between zero and one. For this purpose we extend the theory of the congruence. The new congruence is over the set of the real numbers and it is called the “real congruence" or the “real modulus". We will refer to the existing congruence by the “integer congruence" or the “integer modulus". This extension will define new terms and redefine the existing terms. As the properties and the theorems of the integer modulus are extended as well. Modified Diffie-Hellman key exchange protocol is produced a sharing, secure and decimal secret key for the the cryptosystems that depend on decimal numbers.Keywords: Extended theory of the congruence, modified Diffie- Hellman protocol.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15901625 Design and Analysis of Piping System with Supports Using CAESAR-II
Authors: M. Jamuna Rani, K. Ramanathan
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A steam power plant is housed with various types of equipments like boiler, turbine, heat exchanger etc. These equipments are mainly connected with piping systems. Such a piping layout design depends mainly on stress analysis and flexibility. It will vary with respect to pipe geometrical properties, pressure, temperature, and supports. The present paper is to analyze the presence and effect of hangers and expansion joints in the piping layout/routing using CAESAR-II software. Main aim of piping stress analysis is to provide adequate flexibility for absorbing thermal expansion, code compliance for stresses and displacement incurred in piping system. The design is said to be safe if all these are in allowable range as per code. In this study, a sample problem is considered for analysis as per power piping ASME B31.1 code and the results thus obtained are compared.
Keywords: ASTM B31.1, hanger, expansion joint, CAESAR-II.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 51421624 A Feature-based Invariant Watermarking Scheme Using Zernike Moments
Authors: Say Wei Foo, Qi Dong
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In this paper, a novel feature-based image watermarking scheme is proposed. Zernike moments which have invariance properties are adopted in the scheme. In the proposed scheme, feature points are first extracted from host image and several circular patches centered on these points are generated. The patches are used as carriers of watermark information because they can be regenerated to locate watermark embedding positions even when watermarked images are severely distorted. Zernike transform is then applied to the patches to calculate local Zernike moments. Dither modulation is adopted to quantize the magnitudes of the Zernike moments followed by false alarm analysis. Experimental results show that quality degradation of watermarked image is visually transparent. The proposed scheme is very robust against image processing operations and geometric attacks.Keywords: Image watermarking, Zernike moments, Featurepoint, Invariance, Robustness.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18521623 WLAN Positioning Based on Joint TOA and RSS Characteristics
Authors: Peerapong Uthansakul, Monthippa Uthansakul
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WLAN Positioning has been presented by many approaches in literatures using the characteristics of Received Signal Strength (RSS), Time of Arrival (TOA) or Time Difference of Arrival (TDOA), Angle of Arrival (AOA) and cell ID. Among these, RSS approach is the simplest method to implement because there is no need of modification on both access points and client devices whereas its accuracy is terrible due to physical environments. For TOA or TDOA approach, the accuracy is quite acceptable but most researches have to modify either software or hardware on existing WLAN infrastructure. The scales of modifications are made on only access card up to the changes in protocol of WLAN. Hence, it is an unattractive approach to use TOA or TDOA for positioning system. In this paper, the new concept of merging both RSS and TOA positioning techniques is proposed. In addition, the method to achieve TOA characteristic for positioning WLAN user without any extra modification necessarily appended in the existing system is presented. The measurement results confirm that the proposed technique using both RSS and TOA characteristics provides better accuracy than using only either RSS or TOA approach.Keywords: Received signal strength, Time of arrival, Positioning system, WLAN, Measurement.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17711622 Synthesis and Evaluation of Photovoltaic Properties of an Organic Dye for Dye-Sensitized Solar Cells
Authors: M. Hosseinnejad, K. Gharanjig
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In the present study, metal free organic dyes were prepared and used as photo-sensitizers in dye-sensitized solar cells. Double rhodanine was utilized as the fundamental electron acceptor group to which electron donor aldehyde with varying substituents was attached to produce new organic dye. This dye was first purified and then characterized by analytical techniques. Spectrophotometric evaluations of the prepared dye in solution and on a nano anatase TiO2 substrate were carried out in order to assess possible changes in the status of the dyes in different environments. The results show that the dye form j-type aggregates on the nano TiO2. Additionally, oxidation potential measurements were also carried out. Finally, dye sensitized solar cell based on synthesized dye was fabricated in order to determine the photovoltaic behavior and conversion efficiency of individual dye.Keywords: Conversion efficiency, dye-sensitized solar cell, photovoltaic behavior, sensitizer.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12921621 Trans-Esterification for Production of Biodiesel from Waste Frying Oil (WFO)
Authors: N. Akhavan Moghaddam, K. Tahvildari, S.Taghvaie
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Biodisel is a type of biofuel having similar properties of diesel fuel but lacks substances (undesirable emissions) such as sulfur, nitrogen and aromatic polycyclic. Upon filtration of waste oil, the biodiesel fuel was produced via carrying out transestrification reaction of triglycerides followed by conducting viscosity, density, flash point, cloud point, pour point and copper strip corrosion tests on the samples and comparing with EN14214 and ASTM 6751 standards and all results were found in the permitted limit. The highest yield of biodiesel production reaction was found 46.6435 g when Sodium Hydroxide catalyst in amount of 0.375g was employed, 44.2347 g when Sodium methoxide catalyst in amount of 0.5g was employed and 56.5124 g when acid sulfuric catalyst in amount of 1g was employed and 47.3290 g when two stage reaction was done.
Keywords: Biodiesel, Transesterification, Basic catalyst, Acidic catalyst.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16191620 Shell Closures in Exotic Nuclei
Authors: G. Saxena, D. Singh, M. Kaushik,
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Inspired by the recent experiments [1]-[3] indicating unusual doubly magic nucleus 24O which lies just at the neutron drip-line and encouraged by the success of our relativistic mean-field (RMF) plus state dependent BCS approach for the description of the ground state properties of the drip-line nuclei [23]-[27], we have further employed this approach, across the entire periodic table, to explore the unusual shell closures in exotic nuclei. In our RMF+BCS approach the single particle continuum corresponding to the RMF is replaced by a set of discrete positive energy states for the calculations of pairing energy. Detailed analysis of the single particle spectrum, pairing energies and densities of the nuclei predict the unusual proton shell closures at Z = 6, 14, 16, 34, and unusual neutron shell closures at N = 6, 14, 16, 34, 40, 70, 112.Keywords: Relativistic Mean Field theory, Magic Nucleus, Si isotopes, Shell Closure.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15101619 Simulation of Die Casting Process in an Industrial Helical Gearbox Flange Die
Authors: Mehdi Modabberifar, Behrouz Raad, Bahman Mirzakhani
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Flanges are widely used for connecting valves, pipes and other industrial devices such as gearboxes. Method of producing a flange has a considerable impact on the manner of their involvement with the industrial engines and gearboxes. By Using die casting instead of sand casting and machining for manufacturing flanges, production speed and dimensional accuracy of the parts increases. Also, in die casting, obtained dimensions are close to final dimensions and hence the need for machining flanges after die casting process decreases which makes a significant savings in raw materials and improves the mechanical properties of flanges. In this paper, a typical die of an industrial helical gearbox flange (size ISO 50) was designed and die casting process for producing this type of flange was simulated using ProCAST software. The results of simulation were used for optimizing die design. Finally, using the results of the analysis, optimized die was built.
Keywords: Die casting, finite element, flange.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28381618 Cutting and Breaking Events in Telugu
Authors: Vasanta Duggirala, Y. Viswanatha Naidu
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This paper makes a contribution to the on-going debate on conceptualization and lexicalization of cutting and breaking (C&B) verbs by discussing data from Telugu, a language of India belonging to the Dravidian family. Five Telugu native speakers- verbalizations of agentive actions depicted in 43 short video-clips were analyzed. It was noted that verbalization of C&B events in Telugu requires formal units such as simple lexical verbs, explicator compound verbs, and other complex verb forms. The properties of the objects involved, the kind of instruments used, and the manner of action had differential influence on the lexicalization patterns. Further, it was noted that all the complex verb forms encode 'result' and 'cause' sub-events in that order. Due to the polysemy associated with some of the verb forms, our data does not support the straightforward bipartition of this semantic domain.Keywords: Cluster analysis, Cutting and breaking events, Polysemy, Semantic extension, Telugu.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21511617 Failure Criterion for Mixed Mode Fracture of Cracked Wood Specimens
Authors: Mahdi Fakoor, Seyed Mohammad Navid Ghoreishi
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Investigation of fracture of wood components can prevent from catastrophic failures. Created fracture process zone (FPZ) in crack tip vicinity has important effect on failure of cracked composite materials. In this paper, a failure criterion for fracture investigation of cracked wood specimens under mixed mode I/II loading is presented. This criterion is based on maximum strain energy release rate and material nonlinearity in the vicinity of crack tip due to presence of microcracks. Verification of results with available experimental data proves the coincidence of the proposed criterion with the nature of fracture of wood. To simplify the estimation of nonlinear properties of FPZ, a damage factor is also introduced for engineering and application purposes.
Keywords: Fracture criterion, mixed mode loading, damage zone, microcracks.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15571616 n− Strongly Gorenstein Projective, Injective and Flat Modules
Authors: Jianmin Xing Wei Shao
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Let R be a ring and n a fixed positive integer, we investigate the properties of n-strongly Gorenstein projective, injective and flat modules. Using the homological theory , we prove that the tensor product of an n-strongly Gorenstein projective (flat) right R -module and projective (flat) left R-module is also n-strongly Gorenstein projective (flat). Let R be a coherent ring ,we prove that the character module of an n -strongly Gorenstein flat left R -module is an n-strongly Gorenstein injective right R -module . At last, let R be a commutative ring and S a multiplicatively closed set of R , we establish the relation between n -strongly Gorenstein projective (injective , flat ) R -modules and n-strongly Gorenstein projective (injective , flat ) S−1R-modules. All conclusions in this paper is helpful for the research of Gorenstein dimensions in future.
Keywords: Commutative ring, n-strongly Gorenstein projective, n-Strongly Gorenstein injective, n-strongly Gorenstein flat, S-ring.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15621615 Thermomechanical and Metallurgical Analysis of SMA and GTA Welded Low Carbon Steel Butt Joints
Authors: J. Dutta, P. Pranith Kumar Reddy
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This research paper portrays a comparative analysis of thermomechanical behaviour of Shielded Metal Arc Welding (SMAW) and Gas Tungsten Arc Welding (GTAW) of low carbon steel of AISI 1020 grade butt joints. The thermal history has been obtained by experimental work. We have focused on temperature dependent cooling rate as depicted by Adam’s two-dimensional model. The effect of moving point heat source of SMAW and GTAW on mechanical properties has been judged by optical and scanning electron micrographs of different regions in weld joints. The microhardness study has been carried to visualize the joint strength due to formation of different phases.
Keywords: Shielded metal arc welding, gas tungsten arc welding, low carbon steel, microhardness study, thermal history, microscopic morphology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22061614 Modeling Thermo-Photo-Voltaic Selective Emitter Based on a Semi-Transparent Emitter with Integrated Narrow Band-Pass Pre-Filter
Authors: F. Stake
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This work is a parametric study combining simple and well known optical theories. These simple theories are arranged to form part of one answer to the question: “Can a semi-transparent Thermo-Photo-Voltaic (TPV) emitter have an optical extinction spectrum so much greater than its optical absorption spectrum that it becomes its own band-pass pre-filter, and if so, how well might it be expected to suppress light of undesired wavelengths?” In the report, hypothetical materials and operating temperatures will be used for comparative analyses only. Thermal emission properties of these hypothetical materials were created using two openly available FORTRAN programs. Results indicate that if using highly transparent materials it may be possible to create a thermal emitter that is its own band-pass pre-filter.Keywords: Christensen effect, DISORT, index of refraction, scattering.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6121613 Novel Glycopolymers Containing Carbohydrate Moiety: Copolymerization and Thermal Properties
Authors: Liliana M. Ştefan, Ana M. Pană, Geza Bandur, Marcel Popa, Lucian M. Rusnac
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Polymers are one of the most widely used materials in our every day life. The subject of renewable resources has attracted great attention in the last period of time. New polymeric materials derived from renewable resources, like carbohydrates draw attention to public eye especially because of their biocompatibility and biodegradability. The aim of our paper was to obtain environmentally compatible polymers from monosaccharides. Novel glycopolymers based on D-glucose have been obtained from copolymerization of a new monomer carrying carbohydrate moiety with methyl methacrylate (MMA) via free radical bulk polymerization. Differential scanning calorimetry (DSC) was performed in order to study the copolymerization process of the monomer into the chosen co-monomer; the activation energy of this process was evaluated using Ozawa method. The copolymers obtained were characterized using ATR-FTIR spectroscopy. The thermal stability of the obtained products was studied by thermogravimetry (TG).
Keywords: DSC, glycopolymer, monosaccarides, TG.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17121612 Treatment of Chrome Tannery Wastewater by Biological Process - A Mini Review
Authors: Supriyo Goswami, Debabrata Mazumder
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Chrome tannery wastewater causes serious environmental hazard due to its high pollution potential. As a result, rigorous treatment is necessary for abatement of pollution from this type of wastewater. There are many research studies on chrome tannery wastewater treatment in the field of physical, chemical, and biological methods. In general, biological treatment process is found ineffective for direct application because of adverse effects by toxic chromium, sulphide, chloride etc. However, biological methods were employed mainly for a few sub processes generating significant amount of organic matter and without chromium, chlorides etc. In this context the present paper reviews the characteristics feature and pollution potential of wastewater generated from chrome tannery units and treatment of the same. The different biological processes used earlier and their chronological development for treatment of the chrome tannery wastewater are thoroughly reviewed in this paper. In this regard, the scope of hybrid bioreactor - an advanced technology option has also been explored, as this kind of treatment is well suited for the wastewater having inhibitory substances.
Keywords: Composite tannery wastewater, biological treatment, Hybrid bioreactor, Organic removal
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 42291611 Moving Beyond the Limits of Disability Inclusion: Using the Concept of Belonging Through Friendship to Improve the Outcome of the Social Model of Disability
Authors: Luke S. Carlos A. Thompson
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The medical model of disability, though beneficial for the medical professional, is often exclusionary, restrictive and dehumanizing when applied to the lived experience of disability. As a result, a critique of this model was constructed called the social model of disability. Much of the language used to articulate the purpose behind the social model of disability can be summed up within the word inclusion. However, this essay asserts that inclusiveness is an incomplete aspiration. The social model, as it currently stands, does not aid in creating a society where those with impairments actually belong. Rather, the social model aids in lessening the visibility, or negative consequence of, difference. Therefore, the social model does not invite society to welcome those with physical and intellectual impairments. It simply aids society in ignoring the existence of impairment by removing explicit forms of exclusion. Rather than simple inclusion, then, this essay uses John Swinton’s concept of friendship and Jean Vanier’s understanding of belonging to better articulate the intended outcome of the social model—a society where everyone can belong.Keywords: Belong, community, disability, exclusion, friendship, inclusion.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23041610 Study of the Effects of Ceramic Nano-Pigments in Cement Mortar Corrosion Caused by Chlorine Ions
Authors: R. Moradpour, S.B. Ahmadi, T. Parhizkar, M. Ghodsian, E. Taheri-Nassaj
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Superfine pigments that consist of natural and artificial pigments and are made of mineral soil with special characteristics are used in cementitious materials for various purposes. These pigments can decrease the amount of cement needed without loss of performance and strength and also change the monotonous and turbid colours of concrete into various attractive and light colours. In this study, the mechanical strength and resistance against chloride and halogen attacks of cement mortars containing ceramic nano-pigments in an affected environment are studied. This research suggests utilisation of ceramic nano-pigments between 50 and 1000 nm, obtaining full-depth coloured concrete, preventing chlorine penetration in the concrete up to a certain depth, and controlling corrosion in steel rebar with the Potentiostat (EG&G) apparatus.
Keywords: Nano-structures, Corrosion, Mechanical properties, Nano-pigments.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28121609 Study and Analysis of Optical Intersatellite Links
Authors: Boudene Maamar, Xu Mai
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Optical Intersatellite Links (OISLs) are wireless communications using optical signals to interconnect satellites. It is expected to be the next generation wireless communication technology according to its inherent characteristics like: an increased bandwidth, a high data rate, a data transmission security, an immunity to interference, and an unregulated spectrum etc. Optical space links are the best choice for the classical communication schemes due to its distinctive properties; high frequency, small antenna diameter and lowest transmitted power, which are critical factors to define a space communication. This paper discusses the development of free space technology and analyses the parameters and factors to establish a reliable intersatellite links using an optical signal to exchange data between satellites.Keywords: Optical intersatellite links, optical wireless communications, free space optical communications, next generation wireless communication.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30501608 Effects of the Stock Market Dynamic Linkages on the Central and Eastern European Capital Markets
Authors: Ioan Popa, Cristiana Tudor, Radu Lupu
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The interdependences among stock market indices were studied for a long while by academics in the entire world. The current financial crisis opened the door to a wide range of opinions concerning the understanding and measurement of the connections considered to provide the controversial phenomenon of market integration. Using data on the log-returns of 17 stock market indices that include most of the CEE markets, from 2005 until 2009, our paper studies the problem of these dependences using a new methodological tool that takes into account both the volatility clustering effect and the stochastic properties of these linkages through a Dynamic Conditional System of Simultaneous Equations. We find that the crisis is well captured by our model as it provides evidence for the high volatility – high dependence effect.Keywords: Stock market interdependences, Dynamic System ofSimultaneous Equations, financial crisis
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17851607 Difference of Properties on Surface Leakage and Discharge Currents of Porcelain Insulator Material
Authors: Waluyo, Ngapuli I. Sinisuka, Suwarno, Maman A. Djauhari
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This paper presents the experimental results of comparison between leakage currents and discharge currents. The leakage currents were obtained on polluted porcelain insulator. Whereas, the discharge currents were obtained on lightly artificial polluted porcelain specimen. The conducted measurements were leakage current or discharge current and applied voltage. The insulator or specimen was in a hermetically sealed chamber, and the current waveforms were analyzed using FFT. The result indicated that the leakage current (LC) on low RH condition the fifth harmonic would be visible, and followed by the seventh harmonic. The insulator had capacitive property. Otherwise, on 99% relative humidity, the fifth harmonic would also be visible, and the phase angle reached up to 12.2 degree. Whereas, on discharge current, the third harmonic would be visible, and followed by fifth harmonic. The third harmonic would increase as pressure reduced. On this condition, the specimen had a non-linear characteristicsKeywords: leakage current, discharge current, third harmonic, fifth harmonic, porcelain.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16551606 Effect of S-Girdling on Fruit Growth and Fruit Quality of Wax Apple
Authors: Minh Tuan, Nguyen, Chung –Ruey, Yen
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The study was performed to evaluate the effect of Sgirdling, fruit thinning plus bagging with 2,4-D application, fruit thinning plus bagging on growth and quality of wax apple fruit. Girdling was applied three week before flowering. The 2,4-D was sprayed at the small bud and petal fall stage. The effect of all treatments on fruit growth was measured weekly. The physical and biochemical quality characteristics of the fruits were recorded. The results showed that no significant effect on number of bud among treatments. S-girdling, 2,4-D application produced the lowest bud drop, fruit drop compared to untreated control. Moreover, S-girdling enhanced faster fruit growth producing the best final fruit length and diameter than the control treatment. It was also observed that Sgirdling greatly increased fruit set, fruit weight as well as total soluble solid, reduced fruit crack, and titratable acidity. In conclusion, S-girdling had a distinctive and significant effect on most of the fruit quality characteristics assessed. Application 2,4-D was also recommended as the industry norm to increase fruit set, and fruit quality in wax apple.Keywords: Wax apple, S-girdling, 2, 4-D, fruit bagging, fruit thinning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30171605 A Practical Construction Technique to Enhance the Performance of Rock Bolts in Tunnels
Authors: O. Chaudhari, A. N. Ghafar, G. Zirgulis, M. Mousavi, T. Ellison, S. Pousette, P. Fontana
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In Swedish tunnel construction, a critical issue that has been repeatedly acknowledged is corrosion and, consequently, failure of the rock bolts in rock support systems. The defective installation of rock bolts results in the formation of cavities in the cement mortar that is regularly used to fill the area under the dome plates. These voids allow for water-ingress to the rock bolt assembly, which results in corrosion of rock bolt components and eventually failure. In addition, the current installation technique consists of several manual steps with intense labor works that are usually done in uncomfortable and exhausting conditions, e.g., under the roof of the tunnels. Such intense tasks also lead to a considerable waste of materials and execution errors. Moreover, adequate quality control of the execution is hardly possible with the current technique. To overcome these issues, a non-shrinking/expansive cement-based mortar filled in the paper packaging has been developed in this study which properly fills the area under the dome plates without or with the least remaining cavities, ultimately that diminishes the potential of corrosion. This article summarizes the development process and the experimental evaluation of this technique for the installation of rock bolts. In the development process, the cementitious mortar was first developed using specific cement and shrinkage reducing/expansive additives. The mechanical and flow properties of the mortar were then evaluated using compressive strength, density, and slump flow measurement methods. In addition, isothermal calorimetry and shrinkage/expansion measurements were used to elucidate the hydration and durability attributes of the mortar. After obtaining the desired properties in both fresh and hardened conditions, the developed dry mortar was filled in specific permeable paper packaging and then submerged in water bath for specific intervals before the installation. The tests were enhanced progressively by optimizing different parameters such as shape and size of the packaging, characteristics of the paper used, immersion time in water and even some minor characteristics of the mortar. Finally, the developed prototype was tested in a lab-scale rock bolt assembly with various angles to analyze the efficiency of the method in real life scenario. The results showed that the new technique improves the performance of the rock bolts by reducing the material wastage, improving environmental performance, facilitating and accelerating the labor works, and finally enhancing the durability of the whole system. Accordingly, this approach provides an efficient alternative for the traditional way of tunnel bolt installation with considerable advantages for the Swedish tunneling industry.
Keywords: corrosion, durability, mortar, rock bolt
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4281604 Consistent Modeling of Functional Dependencies along with World Knowledge
Authors: Sven Rebhan, Nils Einecke, Julian Eggert
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In this paper we propose a method for vision systems to consistently represent functional dependencies between different visual routines along with relational short- and long-term knowledge about the world. Here the visual routines are bound to visual properties of objects stored in the memory of the system. Furthermore, the functional dependencies between the visual routines are seen as a graph also belonging to the object-s structure. This graph is parsed in the course of acquiring a visual property of an object to automatically resolve the dependencies of the bound visual routines. Using this representation, the system is able to dynamically rearrange the processing order while keeping its functionality. Additionally, the system is able to estimate the overall computational costs of a certain action. We will also show that the system can efficiently use that structure to incorporate already acquired knowledge and thus reduce the computational demand.Keywords: Adaptive systems, Knowledge representation, Machinevision, Systems engineering
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17031603 Degradability Studies of Photodegradable Plastic Film
Authors: Nurul, A.M.Y., Rahmah, M., Muhammad, A.
Abstract:
Polypropylene blended with natural oil and pigment additives has been studied. Different formulations for each compound were made into polybag used for cultivation of oil palm seedlings for strength and mechanical properties studies. One group of sample was exposed under normal sunlight to initiate degradation and another group of sample was placed under shaded area for five months. All samples were tested for tensile strength to determine the degradation effects. The tensile strength of directly exposed sunlight samples and shaded area showed up to 50% and 25% degradation respectively. However, similar reduction of Young’s modulus for all samples was found for both exposures. Structural investigations were done using FTIR to detect deformation. The natural additives that were used in the studies were all natural and environmental friendly
Keywords: Agriculture, mechanical strength, photodegradable polymer.
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