Search results for: web presence.
1085 Online Teaching and Learning Processes: Declarative and Procedural Knowledge
Authors: Eulalia Torras, Andreu Bellot
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To know whether students’ achievements are the result of online interaction and not just a consequence of individual differences themselves, it seems essential to link the teaching presence and social presence to the types of knowledge built. The research aim is to analyze the social presence in relation to two types of knowledge, declarative and procedural. Qualitative methodology has been used. The analysis of the contents was based on an observation protocol that included community of enquiry indicators and procedural and declarative knowledge indicators. The research has been conducted in three phases that focused on an observational protocol and indicators, results and conclusions. Results show that the teaching-learning processes have been characterized by the patterns of presence and types of knowledge. Results also show the importance of social presence support provided by the teacher and the students, not only in regard to the nature of the instructional support but also concerning how it is presented to the student and the importance that is attributed to it in the teaching-learning process, that is, what it is that assistance is offered on. In this study, we find that the presence based on procedural guidelines and declarative reflection, the management of shared meaning on the basis of the skills and the evidence of these skills entail patterns of learning. Nevertheless, the importance that the teacher attributes to each support aspect has a bearing on the extent to which the students reflect more on the given task.Keywords: Education, online, teaching and learning processes, knowledge.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20581084 Pathogen Removal Under the Influence of Iron
Authors: Umapriya.R., S.Shrihari
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Drinking water is one of the most valuable resources available to mankind. The presence of pathogens in drinking water is highly undesirable. Because of the Lateritic soil, the iron concentrations were high in ground water. High concentration of iron and other trace elements could restrict bacterial growth and modify their metabolic pattern as well. The bacterial growth rate reduced in the presence of iron in water. This paper presents the results of a controlled laboratory study conducted to assess the inhibition of micro-organism (pathogen) in well waters in the presence of dissolved iron concentrations. Synthetic samples were studied in the laboratory and the results compared with field samples. Predictive model for microbial inhibition in the presence of iron is presented. It was seen that the bore wells, open wells and the field results varied, probably due to the nature of micro-organism utilizing the iron in well waters.Keywords: Disinfection, Disinfectant, Iron, Laterite.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18831083 Admission Control Approaches in the IMS Presence Service
Authors: Muhammad T. Alam, Zheng Da Wu
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In this research, we propose a weighted class based queuing (WCBQ) mechanism to provide class differentiation and to reduce the load for the IMS (IP Multimedia Subsystem) presence server (PS). The tasks of admission controller for the PS are demonstrated. Analysis and simulation models are developed to quantify the performance of WCBQ scheme. An optimized dropping time frame has been developed based on which some of the preexisting messages are dropped from the PS-buffer. Cost functions are developed and simulation comparison has been performed with FCFS (First Come First Served) scheme. The results show that the PS benefits significantly from the proposed queuing and dropping algorithm (WCBQ) during heavy traffic.Keywords: Admission control, presence, queuing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15621082 S-S Coupling of Thiols to Disulfides Using Ionic Liquid in the Presence of Free Nano-Fe2O3 Catalyst
Authors: Askar Sabet, Abdolrasoul Fakhraee, Motahahre Ramezanpour, Noorallah Alipour
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An efficient and green method for oxidation of thiols to the corresponding disulfides is reported using ionic liquid [HSO3N(C2H4OSO3H)3] in the presence of free nano-Fe2O3 at 60°C. Ionic liquid is selective oxidant for S-S Coupling variety aliphatic and aromatic of thiols to corresponding disulfide in the presence of free nano-Fe2O3 as recoverable catalyst. Reaction has been performed in methanol as an inexpensive solvent. This reaction is clean and easy work-up with no side reaction.
Keywords: Thiol, Disulfide, Ionic liquid, Free Nano-Fe2O3, Oxidation, Coupling.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28011081 Assessing Mobile Robotic Telepresence Based On Measures of Social Telepresence
Authors: A. Bagherzadhalimi, E. Di Maria
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The feedbacks obtained regarding the sense of presence from pilot users operating a Mobile Robotic presence (MRP) system to visit a simulated museum are reported in this paper. The aim is to investigate how much the perception of system’s usefulness and ease of use is affected by operators’ sense of social telepresence (presence) in the remote location. Therefore, scenarios of visiting a museum are simulated and the user operators are supposed to perform some regular tasks inside the remote environment including interaction with local users, navigation and visiting the artworks. Participants were divided into two groups, those who had previous experience of operation and interaction with a MRP system and those who never had experience. Based on the results, both groups provided different feedbacks. Moreover, there was a significant association between user’s sense of presence and their perception of system usefulness and ease of use.
Keywords: Mobile Robotic Telepresence, Museum, Social Telepresence, Usability test.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17071080 Analysis of Design Structuring and Performance of CPW Fed UWB Antenna in Presence of Human Arm Model
Authors: Narbada Prasad Gupta, Mithilesh Kumar
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A compact Ultra Wide Band (UWB) antenna with coplanar waveguide feed has been designed and results are verified in this paper. The antenna has been designed on FR4 substrate with dielectric constant (εr) of 4.4 and dimensions of 32mm x 26mm x 0.8mm. The presented antenna shows return loss characteristics in the band of 3.1 to 10.6 GHz as prescribed by FCC, USA. Parametric studies have been done and results thus obtained have been presented. Simulated results have been verified on Rohde & Swartz VNA. The measured results are in good agreement with simulated results which make the presented antenna suitable to be used for wearable applications. Performance analysis of antenna has also been shown in the presence of three layered Human Arm model. Results obtained in presence of Human Arm model has been compared with that in free space.Keywords: CPW feed, Human Arm model, UWB, wearable antenna.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15071079 Visualized Flow Patterns around and inside a Two-Sided Wind-Catcher in the Presence of Upstream Structures
Authors: M. Afshin, A. Sohankar, M. Dehghan Manshadi, M. R. Daneshgar, G. R. Dehghan Kamaragi
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In this paper, the influence of upstream structures on the flow patternaround and inside the wind-catcher is experimentally investigated by smoke flow visualization techniques. Wind-catchers are an important part of natural ventilation in residential buildings or public places such as shopping centers, libraries, etc. Wind-catchers might be also used in places of high urban densities; hence their potential to provide natural ventilation is dependent on the presence of upstream structures. In this study, the two-sided wind-catcher model was based on a real wind-catcher observed in the city of Yazd, Iran. The present study focuses on the flow patterns around and inside the isolated two-sided wind-catcher, and on a two-sided wind-catcher in the presence of an upstream structure. The results show that the presence of an upstream structure influences the airflow pattern force and direction. Placing a high upstream structure reverses the airflow direction inside the wind-catcher.
Keywords: Natural Ventilation, Smoke Flow Visualization, Two-Sided Wind-Catcher.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19891078 Recycling of Polymers in the Presence of Nanocatalysts: A Green Approach towards Sustainable Environment
Authors: Beena Sethi
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This work involves the degradation of plastic waste in the presence of three different nanocatalysts. A thin film of LLDPE was formed with all three nanocatalysts separately in the solvent. Thermo Gravimetric Analysis (TGA) and Differential Scanning Calorimetric (DSC) analysis of polymers suggest that the presence of these catalysts lowers the degradation temperature and the change mechanism of degradation. Gas chromatographic analysis was carried out for two films. In gas chromatography (GC) analysis, it was found that degradation of pure polymer produces only 32% C3/C4 hydrocarbons and 67.6% C5/C9 hydrocarbons. In the presence of these catalysts, more than 80% of polymer by weight was converted into either liquid or gaseous hydrocarbons. Change in the mechanism of degradation of polymer was observed therefore more C3/C4 hydrocarbons along with valuable feedstock are produced. Adjustment of dose of nanocatalyst, use of nano-admixtures and recycling of catalyst can make this catalytic feedstock recycling method a good tool to get sustainable environment. The obtained products can be utilized as fuel or can be transformed into other useful products. In accordance with the principles of sustainable development, chemical recycling i.e. tertiary recycling of polymers along with the reuse (zero order recycling) of plastics can be the most appropriate and promising method in this direction. The tertiary recycling is attracting much attention from the viewpoint of the energy resource.
Keywords: Degradation, differential scanning calorimetry, feedstock recycling, gas chromatography, thermogravimetric analysis. DSC.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21561077 The Effects of Peristalsis on Dispersion of a Micropolar Fluid in the Presence of Magnetic Field
Authors: Habtu Alemayehu, G. Radhakrishnamacharya
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The paper presents an analytical solution for dispersion of a solute in the peristaltic motion of a micropolar fluid in the presence of magnetic field and both homogeneous and heterogeneous chemical reactions. The average effective dispersion coefficient has been found using Taylor-s limiting condition under long wavelength approximation. The effects of various relevant parameters on the average coefficient of dispersion have been studied. The average effective dispersion coefficient increases with amplitude ratio, cross viscosity coefficient and heterogeneous chemical reaction rate parameter. But it decreases with magnetic field parameter and homogeneous chemical reaction rate parameter. It can be noted that the presence of peristalsis enhances dispersion of a solute.Keywords: Peristalsis, Dispersion, Chemical reaction, Magneticfield, Micropolar fluid
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17181076 The Numerical Study of Low Level Jets Formation in South Eastern of Iran
Authors: Mehdi Salehi Barough, Saviz Sehat Kashani, A.A. Bidokhti, A.Ranjbar
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The presence of cold air with the convergent topography of the Lut valley over the valley-s sloping terrain can generate Low Level Jets (LLJ). Moreover, the valley-parallel pressure gradients and northerly LLJ are produced as a result of the large-scale processes. In the numerical study the regional MM5 model was run leading to achieve an appropriate dynamical analysis of flows in the region for summer and winter. The results of this study show the presence of summer synoptical systems cause the formation of north-south pressure gradients in the valley which could be led to the blowing of winds with the velocity more than 14 ms-1 and vulnerable dust and wind storms lasting more than 120 days. Whereas the presence of cold air masses in the region in winter, cause the average speed of LLJs decrease. In this time downslope flows are noticeable in creating the night LLJs.Keywords: Cold advection, Low Level Jet, MM5 Model, Pressure gradient
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15231075 Virtual Reality Classrooms Strategies for Creating a Social Presence
Authors: Elizabeth M. Hodge, M.H.N. Tabrizi, Mary A. Farwell, Karl L. Wuensch
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Delivering course material via a virtual environment is beneficial to today-s students because it offers the interactivity, real-time interaction and social presence that students of all ages have come to accept in our gaming rich community. It is essential that the Net Generation also known as Generation Why, have exposure to learning communities that encompass interactivity to form social and educational connections. As student and professor become interconnected through collaboration and interaction in a virtual learning space, relationships develop and students begin to take on an individual identity. With this in mind the research project was developed to investigate the use of virtual environments on student satisfaction and the effectiveness of course delivery. Furthermore, the project was designed to integrate both interactive (real-time) classes conducted in the Virtual Reality (VR) environment while also creating archived VR sessions for student use in retaining and reviewing course content.Keywords: Virtual Reality, Social Presence, Virtual Environments, Course Delivery Methods.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19121074 Effect of a Magnetic Field on the Onset of Marangoni Convection in a Micropolar Fluid
Authors: Mohd Nasir Mahmud, Ruwaidiah Idris, Ishak Hashim
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With the presence of a uniform vertical magnetic field and suspended particles, thermocapillary instability in a horizontal liquid layer is investigated. The resulting eigenvalue is solved by the Galerkin technique for various basic temperature gradients. It is found that the presence of magnetic field always has a stability effect of increasing the critical Marangoni number.
Keywords: Marangoni convection, Magnetic field, Micropolar fluid, Non-uniform thermal gradient, Thermocapillary.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16361073 Fibers Presence Effects on Air Flow of Attenuator of Spun-Bond Production System
Authors: Nasser Ghassembaglou, Abdullah Bolek, Oktay Yilmaz, Ertan Oznergiz, Hikmet Kocabas, Safak Yilmaz
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Different designs of attenuator systems have been studied in this research; new analysis have been done on existed designs considering fibers effect on air flow; it was comprehended that, at fibers presence, there is an air flow which agglomerates fibers as a negative effect. So some new representations have been designed and CFD analysis has been done on them. Afterwards, one of these representations selected as the most optimum and effective design which is brought in this paper.Keywords: Attenuator, CFD, nanofiber, spun-bond.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18801072 Comparative Evaluation of Color-Based Video Signatures in the Presence of Various Distortion Types
Authors: Aritz Sánchez de la Fuente, Patrick Ndjiki-Nya, Karsten Sühring, Tobias Hinz, Karsten Müller, Thomas Wiegand
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The robustness of color-based signatures in the presence of a selection of representative distortions is investigated. Considered are five signatures that have been developed and evaluated within a new modular framework. Two signatures presented in this work are directly derived from histograms gathered from video frames. The other three signatures are based on temporal information by computing difference histograms between adjacent frames. In order to obtain objective and reproducible results, the evaluations are conducted based on several randomly assembled test sets. These test sets are extracted from a video repository that contains a wide range of broadcast content including documentaries, sports, news, movies, etc. Overall, the experimental results show the adequacy of color-histogram-based signatures for video fingerprinting applications and indicate which type of signature should be preferred in the presence of certain distortions.
Keywords: color histograms, robust hashing, video retrieval, video signature
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14461071 The Study of the Interaction between Catanionic Surface Micelle SDS-CTAB and Insulin at Air/Water Interface
Authors: B. Tah, P. Pal, M. Mahato, R. Sarkar, G. B. Talapatra
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Herein, we report the different types of surface morphology due to the interaction between the pure protein Insulin (INS) and catanionic surfactant mixture of Sodium Dodecyl Sulfate (SDS) and Cetyl Trimethyl Ammonium Bromide (CTAB) at air/water interface obtained by the Langmuir-Blodgett (LB) technique. We characterized the aggregations by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR) in LB films. We found that the INS adsorption increased in presence of catanionic surfactant at air/water interface. The presence of small amount of surfactant induces two-stage growth kinetics due to the pure protein absorption and protein-catanionic surface micelle interaction. The protein remains in native state in presence of small amount of surfactant mixture. Smaller amount of surfactant mixture with INS is producing surface micelle type structure. This may be considered for drug delivery system. On the other hand, INS becomes unfolded and fibrillated in presence of higher amount of surfactant mixture. In both the cases, the protein was successfully immobilized on a glass substrate by the LB technique. These results may find applications in the fundamental science of the physical chemistry of surfactant systems, as well as in the preparation of drug-delivery system.
Keywords: Air/water interface, Catanionic micelle, Insulin, Langmuir-Blodgett film
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24881070 Synthesis, Characterization and Antibacterial Screening of 3-Hydroxy-2-[3-(2/3/4-Methoxybenzoyl)Thioureido]Butyric Acid
Authors: M. S. M. Yusof, R. Ramli, S. K. C. Soh, N. Ismail, N. Ngah
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This study presents the synthesis of a series of methoxybenzoylthiourea amino acid derivatives. The compounds were obtained from the reactions between 2/3/4-methoxybenzoyl isothiocyanate with threonine. All of the compounds were characterized via mass spectrometry, 1H and 13C NMR spectrometry, UV-Vis spectrophotometer and FT-IR spectroscopy. Mass spectra for all of the compounds showed the presence of molecular ion [M]+ peaks at m/z 312, which are in agreement to the calculated molecular weight. For 1H NMR spectra, the presence of OCH3, C=S-NH and C=O-NH protons were observed within range of δH 3.8-4.0 ppm, 11.1-11.5 ppm and 10.0-11.5 ppm, respectively. 13C NMR spectra in all compounds displayed the presence of OCH3, C=O-NH, C=O-OH and C=S carbon resonances within range of δC 55.0-57.0 ppm, 165.0-168.0 ppm, 170.0-171.0 ppm and 180.0-182.0 ppm, respectively. In UV spectra, two absorption bands have been observed and both were assigned to the n-π* and π-π* transitions. Six vibrational modes of v(N-H), v(O-H), v(C=O-OH), v(C=O-NH), v(C=C) aromatic and v(C=S) appeared in the FT-IR spectra within the range of 3241-3467 cm-1, 2976-3302 cm-1, 1720-1768 cm-1, 1655-1672 cm-1, 1519-1525 cm-1 and 754-763 cm-1, respectively. The antibacterial activity for all of the compounds was screened against Staphylococcus aureus, Staphylococcus epidermidis, Salmonella typhimurium and Escherichia coli. However, no activity was observed.
Keywords: Methoxybenzoyl isothiocyanate, amino acid, threonine, antibacterial.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9251069 Preparation and Characterization of Chitosan / Polyacrylic Acid / Ag-Nanoparticles Composite Membranes
Authors: Abdel-Mohdy, A. Abou-Okeil, S. El-Sabagh, S. M. El-Sawy
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Chitosan polyacrylic acid composite membranes were prepared by a bulk polymerization method in presence of N, N'- methylene bisacrylamide (crosslinker) and ammonium persulphate as initiator. Membranes prepared from this copolymer in presence and absence of Ag nanoparticles were characterized by measuring mechanical and physical properties, water up-take and antibacterial properties. The results obtained indicated that the prepared membranes have antibacterial properties which increase with adding Ag nanoparticles.Keywords: Ag nanoparticles, antimicrobial, composites, Membrane, physical properties.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27511068 Effect of TCSR on Measured Impedance by Distance Protection in Presence Single Phase to Earth Fault
Authors: Mohamed Zellagui, Abdelaziz Chaghi
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This paper presents the impact study of apparent reactance injected by series Flexible AC Transmission System (FACTS) i.e. Thyristor Controlled Series Reactor (TCSR) on the measured impedance of a 400 kV single electrical transmission line in the presence of phase to earth fault with fault resistance. The study deals with an electrical transmission line of Eastern Algerian transmission networks at Group Sonelgaz (Algerian Company of Electrical and Gas) compensated by TCSR connected at midpoint of the line. This compensator used to inject active and reactive powers is controlled by three TCSR-s. The simulations results investigate the impacts of the TCSR on the parameters of short circuit calculation and parameters of measured impedance by distance relay in the presence of earth fault for three cases study.Keywords: TCSR, Transmission line, Apparent reactance, Earth fault, Symmetrical components, Distance protection, Measured impedance.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25501067 Coexistence of Two Different Types of Intermittency near the Boundary of Phase Synchronization in the Presence of Noise
Authors: Olga I. Moskalenko, Maksim O. Zhuravlev, Alexey A. Koronovskii, Alexander E. Hramov
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Intermittent behavior near the boundary of phase synchronization in the presence of noise is studied. In certain range of the coupling parameter and noise intensity the intermittency of eyelet and ring intermittencies is shown to take place. Main results are illustrated using the example of two unidirectional coupled Rössler systems. Similar behavior is shown to take place in two hydrodynamical models of Pierce diode coupled unidirectional.Keywords: Chaotic oscillators, phase synchronization, noise, intermittency of intermittencies, control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19521066 Stereoselective Reduction of Amino Ketone with Sodium Borohydride in the Presence of Metal Chloride. A Simple Pathway to S-Propranolol
Authors: R. Inkum, A. Teerawutgulrag, P. Puangsombat, N. Rakariyatham
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Propranolol is worldwide hypertension drug that is active in S-isomer. Patients must use this drug throughout their lives, and this action employsa significant level of expenditure. A simpler synthesis and lower cost can reduce the price for the patient. A sis pathway of S-propranolol starting from protection of (R,S)-propranolol with di-t-butyldicarbonate and then the product is oxidized with pyridiniumchlorochromate. The selective reduction of ketone occurrs with sodiumborohydride in the presence of metal chloride provided S-propranolol.
Keywords: S-propranolol, selective reduction, sodium borohydride, metal chloride
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21591065 Mathematical modeling of Bi-Substrate Enzymatic Reactions with Ping-Pong Mechanism in the Presence of Competitive Inhibitors
Authors: Rafayel A. Azizyan, Aram E. Gevogyan, Valeri B. Arakelyan, Emil S. Gevorgyan
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The mathematical modeling of different biological processes is usually used to predict or assess behavior of systems in which these processes take place. This study deals with mathematical and computer modeling of bi-substrate enzymatic reactions with ping-pong mechanism, which play an important role in different biochemical pathways. Besides that, three models of competitive inhibition were designed using different software packages. The main objective of this study is to represent the results from in silico investigation of bi-substrate enzymatic reactions with ordered pingpong mechanism in the presence of competitive inhibitors, as well as to describe in details the inhibition effects. The simulation of the models with certain kinetic parameters allowed investigating the behavior of reactions as well as determined some interesting aspects concerning influence of different cases of competitive inhibition. Simultaneous presence of two inhibitors, competitive to the S1 and S2 substrates have been studied. Moreover, we have found the pattern of simultaneous influence of both inhibitors.Keywords: Mathematical modeling, bi-substrate enzymatic reactions, ping-pong mechanism, competitive inhibition.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 35921064 Bit Error Rate Analysis of Mobile Communication Network in Nakagami Fading Channel: Interference Considerations
Authors: Manoranjan Das, Benudhar Sahu, Urmila Bhanja
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Co-channel interference is one of the major problems in wireless systems. The effects of co-channel interference in a Nakagami fading channel on the ABER (Average Bit Error Rate) with static nodes are well analyzed. In this paper, we derive the ABER with the presence of mobile nodes. ABER is also derived for mobile systems in the presence of co-channel interference.
Keywords: ABER, co-channel interference, Nakagami fading.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12311063 Nonlinearity and Spectrum Analysis of Drill Strings with Component Mass Unbalance
Authors: F. Abdul Majeed, H. Karki, Y. Abdel Magid, M. Karkoub
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This paper analyses the non linear properties exhibited by a drill string system under various un balanced mass conditions. The drill string is affected by continuous friction in the form of drill bit and well bore hole interactions. This paper proves the origin of limit cycling and increase of non linearity with increase in speed of the drilling in the presence of friction. The spectrum of the frequency response is also studied to detect the presence of vibration abnormalities arising during the drilling process.Keywords: Drill strings, Nonlinear, Spectrum analysis, Unbalanced mass
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17231062 Esterification of Free Fatty Acids in Crude Palm Oil Using Alumina-Doped Sulfated Tin Oxide as a Catalyst
Authors: Worawoot Prasitturattanachai, Kamchai Nuithitikul
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The conventional production of biodiesel from crude palm oil which contains large amounts of free fatty acids in the presence of a homogeneous base catalyst confronts the problems of soap formation and very low yield of biodiesel. To overcome these problems, free fatty acids must be esterified to their esters in the presence of an acid catalyst prior to alkaline-catalyzed transesterification. Sulfated metal oxides are a promising group of catalysts due to their very high acidity. In this research, aluminadoped sulfated tin oxide (SO4 2-/Al2O3-SnO2) catalysts were prepared and used for esterification of free fatty acids in crude palm oil in a batch reactor. The SO4 2-/Al2O3-SnO2 catalysts were prepared from different Al precursors. The results showed that different Al precursors gave different activities of the SO4 2-/Al2O3-SnO2 catalysts. The esterification of free fatty acids in crude palm oil with methanol in the presence of SO4 2-/Al2O3-SnO2 catalysts followed first-order kinetics.
Keywords: Methyl ester, Biodiesel, Esterification, Sulfated tin oxide, Fatty acid.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30601061 The Role of the Accused’s Attorney in the Criminal Justice System of Iran, Mashhad 2014
Authors: Mahdi Karimi
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One of the most basic standards of fair trial is the right to defense, hire an attorney and its presence in the hearing stages. On the one hand, based on the reason and justice, as the legal issues, particularly criminal affairs, become complicated, the accused must benefit from an attorney in the court in order to defend itself which requires legal knowledge. On the other hand, as the judicial system has jurists such as investigation judges at its disposal, the accused must enjoy the same right to defend itself and reject allegations so that the balance is maintained between the litigating parties based on the principle of "equality of arms". The right to adequate time and facilities for defense is cited among the principles and rights relevant to the proceedings in international regulations such as the International Covenant on Civil and Political Rights. The innovations made in the Code of Criminal Procedure in 2013 guaranteed the presence of the accused’s attorney in the proceedings. The present study aims at assessing the result of the aforementioned guarantee in practice and made attempts to investigate the effect of the presence of accused’s attorney on reducing the punishment by asking the question and addressing the statistical population of this study including 48 judges of lower courts and courts of appeal. It seems that in despite of guarantees provided in the new Code of Criminal Procedure, Iran's penal system, does not tolerate the presence of an attorney in practice.Keywords: Defense attorney, equality of arms, fair trial, reducing the penalty, right to defense.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14011060 Extracellular Protein Secreted by Bacillus subtilis ATCC21332 in the Presence of Streptomycin Sulfate
Authors: Hanina M. N., Hairul Shahril M., Ismatul Nurul Asyikin I., Abdul Jalil A. K., Salina M. R., Maryam M. R., Rosfarizan M.
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The extracellular proteins secreted by bacteria may be increased in stressful surroundings, such as in the presence of antibiotics. It appears that many antibiotics, when used at low concentrations, have in common the ability to activate or repress gene transcription, which is distinct from their inhibitory effect. There have been comparatively few studies on the potential of antibiotics as a specific chemical signal that can trigger a variety of biological functions. Therefore, this study was carried out to determine the effect of Streptomycin Sulfate in regulating extracellular proteins secreted by Bacillus subtilis ATCC21332. Results of Microdilution assay showed that the Minimum Inhibition Concentration (MIC) of Streptomycin Sulfate on B. subtilis ATCC21332 was 2.5 mg/ml. The bacteria cells were then exposed to Streptomycin Sulfate at concentration of 0.01 MIC before being further incubated for 48h to 72 h. The extracellular proteins secreted were then isolated and analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Proteins profile revealed that three additional bands with approximate sizes of 30 kDa, 22 kDa and 23 kDa were appeared for the treated bacteria with Streptomycin Sulfate. Thus, B. subtilis ATCC21332 in stressful condition with the presence of Streptomycin Sulfate at low concentration could induce the extracellular proteins secretion.
Keywords: Bacillus subtilis ATCC21332, Streptomycin Sulfate, extracellular proteins.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 31671059 Approximation for Average Error Probability of BPSK in the Presence of Phase Error
Authors: Yeonsoo Jang, Dongweon Yoon, Ki Ho Kwon, Jaeyoon Lee, Wooju Lee
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Phase error in communications systems degrades error performance. In this paper, we present a simple approximation for the average error probability of the binary phase shift keying (BPSK) in the presence of phase error having a uniform distribution on arbitrary intervals. For the simple approximation, we use symmetry and periodicity of a sinusoidal function. Approximate result for the average error probability is derived, and the performance is verified through comparison with simulation result.Keywords: Average error probability, Phase shift keying, Phase error
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20491058 Durability of Mortar in Presence of Rice Husk Ash
Authors: Md. Harunur Rashid, Md. Keramat Ali Molla, Tarif Uddin Ahmed
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The purpose of this paper is to investigate the durability of cement mortar in presence of Rice Husk Ash (RHA). The strength and durability of mortar with different replacement level (0%, 10%, 15%, 20%, 25% and 30%) of Ordinary Portland Cement (OPC) by RHA is investigated here. RHA was manufactured from an uncontrolled burning process. Test samples were prepared with river sand of FM 2.73. Samples were kept in controlled environment up to test time. The results show that addition of RHA was shown better results for 20% replacement level than OPC at 90 days. In durability test all samples passed for 20 cycles except 25% and 30% replacement level.Keywords: Rice Husk Ash; durability; mortar, graded sand.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20011057 An Improved Switching Median filter for Uniformly Distributed Impulse Noise Removal
Authors: Rajoo Pandey
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The performance of an image filtering system depends on its ability to detect the presence of noisy pixels in the image. Most of the impulse detection schemes assume the presence of salt and pepper noise in the images and do not work satisfactorily in case of uniformly distributed impulse noise. In this paper, a new algorithm is presented to improve the performance of switching median filter in detection of uniformly distributed impulse noise. The performance of the proposed scheme is demonstrated by the results obtained from computer simulations on various images.Keywords: Switching median filter, Impulse noise, Imagefiltering, Impulse detection.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19551056 Frequency Modulation in Vibro-Acoustic Modulation Method
Authors: D. Liu, D. M. Donskoy
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The vibroacoustic modulation method is based on the modulation effect of high-frequency ultrasonic wave (carrier) by low-frequency vibration in the presence of various defects, primarily contact-type such as cracks, delamination, etc. The presence and severity of the defect are measured by the ratio of the spectral sidebands and the carrier in the spectrum of the modulated signal. This approach, however, does not differentiate between amplitude and frequency modulations, AM and FM, respectfully. This paper is an attempt to explain the generation mechanisms of FM and its correlation with the flaw properties. Here we proposed two possible mechanisms leading to FM modulation based on nonlinear local defect resonance and dynamic acoustoelastic models.
Keywords: Non-destructive testing, nonlinear acoustics, structural health monitoring, acoustoelasticity, local defect resonance.
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