Search results for: Tidal Current Energy Resource Assessment
2702 Modeling and Simulation of PSM DC-DC Buck Converter
Authors: Ramamurthy S, Vanaja Ranjan P
Abstract:
A DC-to-DC converter for applications involving a source with widely varying voltage conditions with loads requiring constant voltage from full load down to no load is presented. The switching regulator considered is a Buck converter with Pulse Skipping Modulation control whereby pulses applied to the switch are blocked or released on output voltage crossing a predetermined value. Results of the study on the performance of regulator circuit are presented. The regulator regulates over a wide input voltage range with slightly higher ripple content and good transient response. Input current spectrum indicates a good EMI performance with crowding of components at low frequency range.Keywords: DC/DC Converter, Pulse Skipping Modulation, Buckregulator, Modulation Factor, Electromagnetic Interference
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24192701 Prediction of Natural Gas Viscosity using Artificial Neural Network Approach
Authors: E. Nemati Lay, M. Peymani, E. Sanjari
Abstract:
Prediction of viscosity of natural gas is an important parameter in the energy industries such as natural gas storage and transportation. In this study viscosity of different compositions of natural gas is modeled by using an artificial neural network (ANN) based on back-propagation method. A reliable database including more than 3841 experimental data of viscosity for testing and training of ANN is used. The designed neural network can predict the natural gas viscosity using pseudo-reduced pressure and pseudo-reduced temperature with AARD% of 0.221. The accuracy of designed ANN has been compared to other published empirical models. The comparison indicates that the proposed method can provide accurate results.
Keywords: Artificial neural network, Empirical correlation, Natural gas, Viscosity
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 32462700 Maternal Smoking and Risk of Childhood Overweight and Obesity: A Meta-Analysis
Authors: Martina Kanciruk, Jac W. Andrews, Tyrone Donnon
Abstract:
The purpose of this study was to determine the significance of maternal smoking for the development of childhood overweight and/or obesity. Accordingly, a systematic literature review of English-language studies published from 1980 to 2012 using the following data bases: MEDLINE, PsychINFO, Cochrane Database of Systematic Reviews, and Dissertation Abstracts International was conducted. The following terms were used in the search: pregnancy, overweight, obesity, smoking, parents, childhood, risk factors. Eighteen studies of maternal smoking during pregnancy and obesity conducted in Europe, Asia, North America, and South America met the inclusion criteria. A meta-analysis of these studies indicated that maternal smoking during pregnancy is a significant risk factor for overweight and obesity; mothers who smoke during pregnancy are at a greater risk for developing obesity or overweight; the quantity of cigarettes consumed by the mother during pregnancy influenced the odds of offspring overweight and/or obesity. In addition, the results from moderator analyses suggest that part of the heterogeneity discovered between the studies can be explained by the region of world that the study occurred in and the age of the child at the time of weight assessment.
Keywords: Childhood obesity, overweight, smoking, parents, risk factors.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20332699 A Promising Approach to Supporting Knowledge-Intensive Business Processes: Business Case Management
Authors: Zeljko Panian
Abstract:
Through the course of this paper we define Business Case Management and its characteristics, and highlight its link to knowledge workers. Business Case Management combines knowledge and process effectively, supporting the ad hoc and unpredictable nature of cases, and coordinate a range of other technologies to appropriately support knowledge-intensive processes. We emphasize the growing importance of knowledge workers and the current poor support for knowledge work automation. We also discuss the challenges in supporting this kind of knowledge work and propose a novel approach to overcome these challenges.
Keywords: Knowledge management, knowledge workers, business process management, business case management, automation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21742698 Status and Requirements of Counter-Cyberterrorism
Authors: Jeong-Tae Kim, Tchanghee Hyun
Abstract:
The number of intrusions and attacks against critical infrastructures and other information networks is increasing rapidly. While there is no identified evidence that terrorist organizations are currently planning a coordinated attack against the vulnerabilities of computer systems and network connected to critical infrastructure, and origins of the indiscriminate cyber attacks that infect computers on network remain largely unknown. The growing trend toward the use of more automated and menacing attack tools has also overwhelmed some of the current methodologies used for tracking cyber attacks. There is an ample possibility that this kind of cyber attacks can be transform to cyberterrorism caused by illegal purposes. Cyberterrorism is a matter of vital importance to national welfare. Therefore, each countries and organizations have to take a proper measure to meet the situation and consider effective legislation about cyberterrorism.Keywords: Cyberterrorism, cyber attack, information security, legislation
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27942697 Detection of Black Holes in MANET Using Collaborative Watchdog with Fuzzy Logic
Authors: Y. Harold Robinson, M. Rajaram, E. Golden Julie, S. Balaji
Abstract:
Mobile ad hoc network (MANET) is a self-configuring network of mobile node connected without wires. A Fuzzy Logic Based Collaborative watchdog approach is used to reduce the detection time of misbehaved nodes and increase the overall truthfulness. This methodology will increase the secure efficient routing by detecting the Black Holes attacks. The simulation results proved that this method improved the energy, reduced the delay and also improved the overall performance of the detecting black hole attacks in MANET.
Keywords: MANET, collaborative watchdog, fuzzy logic, AODV.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13512696 A Rough-set Based Approach to Design an Expert System for Personnel Selection
Authors: Ehsan Akhlaghi
Abstract:
Effective employee selection is a critical component of a successful organization. Many important criteria for personnel selection such as decision-making ability, adaptability, ambition, and self-organization are naturally vague and imprecise to evaluate. The rough sets theory (RST) as a new mathematical approach to vagueness and uncertainty is a very well suited tool to deal with qualitative data and various decision problems. This paper provides conceptual, descriptive, and simulation results, concentrating chiefly on human resources and personnel selection factors. The current research derives certain decision rules which are able to facilitate personnel selection and identifies several significant features based on an empirical study conducted in an IT company in Iran.Keywords: Decision Making, Expert System, PersonnelSelection, Rough Set Theory
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23582695 Effect of Spatially Correlated Disorder on Electronic Transport Properties of Aperiodic Superlattices (GaAs/AlxGa1-xAs)
Authors: F. Bendahma, S. Bentata, S. Cherid, A. Zitouni, S. Terkhi, T. Lantri, Y. Sefir, Z. F. Meghoufel
Abstract:
We examine the electronic transport properties in AlxGa1-xAs/GaAs superlattices. Using the transfer-matrix technique and the exact Airy function formalism, we investigate theoretically the effect of structural parameters on the electronic energy spectra of trimer thickness barrier (TTB). Our numerical calculations showed that the localization length of the states becomes more extended when the disorder is correlated (trimer case). We have also found that the resonant tunneling time (RTT) is of the order of several femtoseconds.
Keywords: Electronic transport properties, structural parameters, superlattice, transfer-matrix technique.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9522694 Measuring the Cognitive Abilities of Teenage Basketball Players in Singapore
Authors: Stella Y. Ng, John B. Peacock, Kay Chuan Tan
Abstract:
This paper discusses the use of a computerized test to measure the decision-making abilities of teenage basketball players in Singapore. There are five sections in this test – Competitive state anxiety inventory-2 (CSAI-2) questionnaire (measures player’s cognitive anxiety, somatic anxiety and self-confidence), Corsi block-tapping task (measures player’s short-term spatial memory), situation awareness global assessment technique (SAGAT) (measures players’ situation awareness in a basketball game), multiple choice questions on basketball knowledge (measures players’ knowledge of basketball rules and concepts), and lastly, a learning test that requires participants to recall and recognize basketball set plays (measures player’s ability to learn and recognize set plays). A total of 25 basketball players, aged 14 to 16 years old, from three secondary school teams participated in this experiment. The results that these basketball players obtained from this cognitive test were then used to compare with their physical fitness and basketball performance.
Keywords: Basketball, cognitive abilities, computerized test, decision-making.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24022693 Finite Element Analysis of Crack Welding Process
Authors: Thomas Jin-Chee Liu
Abstract:
The numerical simulation of the crack welding process is reported in this paper. The thermo-electro-structural coupled-field finite element analysis is adopted to investigate the welding process of crack surfaces. In the simulation, the pressure-dependent and temperature-dependent electrical contact conditions are considered. From the results, the crack surfaces can melt and weld together under the compressive load and electric current. The contact pressure effect must be considered in the finite element analysis to obtain more practical results.
Keywords: Crack welding, contact pressure, Joule heating, finite element, coupled-field.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23622692 Accurate Optical Flow Based on Spatiotemporal Gradient Constancy Assumption
Authors: Adam Rabcewicz
Abstract:
Variational methods for optical flow estimation are known for their excellent performance. The method proposed by Brox et al. [5] exemplifies the strength of that framework. It combines several concepts into single energy functional that is then minimized according to clear numerical procedure. In this paper we propose a modification of that algorithm starting from the spatiotemporal gradient constancy assumption. The numerical scheme allows to establish the connection between our model and the CLG(H) method introduced in [18]. Experimental evaluation carried out on synthetic sequences shows the significant superiority of the spatial variant of the proposed method. The comparison between methods for the realworld sequence is also enclosed.Keywords: optical flow, variational methods, gradient constancy assumption.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21812691 JREM: An Approach for Formalising Models in the Requirements Phase with JSON and NoSQL Databases
Authors: Aitana Alonso-Nogueira, Helia Estévez-Fernández, Isaías García
Abstract:
This paper presents an approach to reduce some of its current flaws in the requirements phase inside the software development process. It takes the software requirements of an application, makes a conceptual modeling about it and formalizes it within JSON documents. This formal model is lodged in a NoSQL database which is document-oriented, that is, MongoDB, because of its advantages in flexibility and efficiency. In addition, this paper underlines the contributions of the detailed approach and shows some applications and benefits for the future work in the field of automatic code generation using model-driven engineering tools.
Keywords: Conceptual modeling, JSON, NoSQL databases, requirements engineering, software development.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10822690 Entrepreneurship, Innovation, Incubator and Economic Development: A Case Study
Authors: Hanadi Mubarak AL-Mubaraki, Aruna, M., Michael Busler
Abstract:
The objective of this paper is twofold: (1) discuss and analyze the successful case studies worldwide, and (2) identify the similarities and differences of case studies worldwide. Design methodology/approach: The nature of this research is mainly method qualitative (multi-case studies, literature review). This investigation uses ten case studies, and the data was mainly collected and organizational documents from the international countries. Finding: The finding of this research can help incubator manager, policy maker and government parties for successful implementation. Originality/value: This paper contributes to the current literate review on the best practices worldwide. Additionally, it presents future perspective for academicians and practitioners.Keywords: Incubators, Economic Development, Entrepreneurship, Innovation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 40192689 Dynamic Model Conception of Improving Services Quality in Railway Transport
Authors: Eva Nedeliakova, Jaroslav Masek, Juraj Camaj
Abstract:
This article describes the results of research focused on quality of railway freight transport services. Improvement of these services has a crucial importance in customer considering on the future use of railway transport. Processes filling the customer demands and output quality assessment were defined as a part of the research. In this contribution is introduced the map of quality planning and the algorithm of applied methodology. It characterizes a model which takes into account characters of transportation with linking a perception services quality in ordinary and extraordinary operation. Despite the fact that rail freight transport has its solid position in the transport market, lots of carriers worldwide have been experiencing a stagnation for a couple of years. Therefore, specific results of the research have a significant importance and belong to numerous initiatives aimed to develop and support railway transport not only by creating a single railway area or reducing noise but also by promoting railway services. This contribution is focused also on the application of dynamic quality models which represent an innovative method of evaluation quality services. Through this conception, time factor, expected, and perceived quality in each moment of the transportation process can be taken into account.Keywords: Quality, railway, transport, service.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17052688 Behavior of Cu-WC-Ti Metal Composite Afterusing Planetary Ball Milling
Authors: A.T.Z. Mahamat, A.M. A Rani, Patthi Husain
Abstract:
Copper based composites reinforced with WC and Ti particles were prepared using planetary ball-mill. The experiment was designed by using Taguchi technique and milling was carried out in an air for several hours. The powder was characterized before and after milling using the SEM, TEM and X-ray for microstructure and for possible new phases. Microstructures show that milled particles size and reduction in particle size depend on many parameters. The distance d between planes of atoms estimated from X-ray powder diffraction data and TEM image. X-ray diffraction patterns of the milled powder did not show clearly any new peak or energy shift, but the TEM images show a significant change in crystalline structure of corporate on titanium in the composites.Keywords: ball milling, microstructures, titanium, tungstencarbides, X-ray
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15962687 Kinetics of Palm Oil Cracking in Batch Reactor
Authors: Farouq Twaiq, Ishaq Al-Anbari, Mustafa Nasser
Abstract:
The kinetics of palm oil catalytic cracking over aluminum containing mesoporous silica Al-MCM-41 (5% Al) was investigated in a batch autoclave reactor at the temperatures range of 573 – 673 K. The catalyst was prepared by using sol-gel technique and has been characterized by nitrogen adsorption and x-ray diffraction methods. Surface area of 1276 m2/g with average pore diameter of 2.54 nm and pore volume of 0.811 cm3/g was obtained. The experimental catalytic cracking runs were conducted using 50 g of oil and 1 g of catalyst. The reaction pressure was recorded at different time intervals and the data were analyzed using Levenberg- Marquardt (LM) algorithm using polymath software. The results show that the reaction order was found to be -1.5 and activation energy of 3200 J/gmol.Keywords: Batch Reactor, Catalytic Cracking, Kinetics, Palm Oil.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 29982686 Combustion Analysis of Suspended Sodium Droplet
Authors: T. Watanabe
Abstract:
Combustion analysis of suspended sodium droplet is performed by solving numerically the Navier-Stokes equations and the energy conservation equations. The combustion model consists of the pre-ignition and post-ignition models. The reaction rate for the pre-ignition model is based on the chemical kinetics, while that for the post-ignition model is based on the mass transfer rate of oxygen. The calculated droplet temperature is shown to be in good agreement with the existing experimental data. The temperature field in and around the droplet is obtained as well as the droplet shape variation, and the present numerical model is confirmed to be effective for the combustion analysis.
Keywords: Combustion, analysis, sodium, droplet.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6982685 Spatial Disparity in Education and Medical Facilities: A Case Study of Barddhaman District, West Bengal, India
Authors: Amit Bhattacharyya
Abstract:
The economic scenario of any region does not show the real picture for the measurement of overall development. Therefore, economic development must be accompanied by social development to be able to make an assessment to measure the level of development. The spatial variation with respect to social development has been discussed taking into account the quality of functioning of a social system in a specific area. In this paper, an attempt has been made to study the spatial distribution of social infrastructural facilities and analyze the magnitude of regional disparities at inter- block level in Barddhman district. It starts with the detailed account of the selection process of social infrastructure indicators and describes the methodology employed in the empirical analysis. Analyzing the block level data, this paper tries to identify the disparity among the blocks in the levels of social development. The results have been subsequently explained using both statistical analysis and geo spatial technique. The paper reveals that the social development is not going on at the same rate in every part of the district. Health facilities and educational facilities are concentrated at some selected point. So overall development activities come to be concentrated in a few centres and the disparity is seen over the blocks.
Keywords: Disparity, inter-block, social development, spatial variation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6452684 Assessment of the Administration and Services of Public Access Computers in Academic Libraries in Kaduna State, Nigeria
Authors: Usman Ahmed Adam, Umar Ibrahim, Ezra S. Gbaje
Abstract:
This study is posed to explore the practice of Public Access Computers (PACs) in academic libraries in Kaduna State, Nigeria. The study aimed to determine the computers and other tools available, their services and challenges of the practices. Three questions were framed to identify number of public computers and tools available, their services and problems faced during the practice. The study used qualitative research design along with semi-constructed interview and observation as tools for data collection. Descriptive analysis was employed to analyze the data. The sample size of the study comprises 52 librarian and IT staff from the seven academic institutions in Kaduna State. The findings revealed that, PACs were provided for access to the Internet, digital resources, library catalogue and training services. The study further explored that, despite the limit number of the computers, users were not allowed to enjoy many services. The study recommends that libraries in Kaduna state should provide more public computers to be able to cover the population of their users; libraries should allow users to use the computers without limitations and restrictions.
Keywords: Academic libraries, computers in the library, digital libraries, public computers.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6152683 Modeling and Simulation of Dynamic Voltage Restorer for Mitigation of Voltage Sags
Authors: S. Ganesh, L. Raguraman, E. Anushya, J. krishnasree
Abstract:
Voltage sags are the most common power quality disturbance in the distribution system. It occurs due to the fault in the electrical network or by the starting of a large induction motor and this can be solved by using the custom power devices such as Dynamic Voltage Restorer (DVR). In this paper DVR is proposed to compensate voltage sags on critical loads dynamically. The DVR consists of VSC, injection transformers, passive filters and energy storage (lead acid battery). By injecting an appropriate voltage, the DVR restores a voltage waveform and ensures constant load voltage. The simulation and experimental results of a DVR using MATLAB software shows clearly the performance of the DVR in mitigating voltage sags.
Keywords: Dynamic voltage restorer, Voltage sags, Power quality, Injection methods.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 42862682 Investigation of the Effect of Milling Time on the Mechanochemical Synthesis of Fe3Al/ Al2O3 Nanocomposite
Authors: B. Ghasemi, A. A. Najafzadeh Khoee
Abstract:
In this study, the effect of mechanical activation on the synthesis of Fe3Al/Al2O3 nanocomposite has been investigated by using mechanochemical method. For this purpose, Aluminum powder and hematite as precursors, with stoichiometric ratio, have been utilized and other effective parameters in milling process were kept constant. Phase formation analysis, crystallite size measurement and lattice strain were studied by X-ray diffraction (XRD) by using Williamson-Hall method as well as microstructure and morphology were explored by Scanning electron microscopy (SEM). Also, Energy-dispersive X-ray spectroscopy (EDX) analysis was used in order to probe the particle distribution. The results showed that after 30-hour milling, the reaction was started, combustibly done and completed.
Keywords: hematite, mechanochemical, milling, nanocomposite
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19052681 Analyzing Disclosure Practice of Religious Nonprofit Organizations using Partial Disclosure Index
Authors: Ruhaya Atan, Saunah Zainon, Roland Yeow Theng Nam, Sharifah Aliman
Abstract:
This study examines the relevance of disclosure practices in improving the accountability and transparency of religious nonprofit organizations (RNPOs). The assessment of disclosure is based on the annual returns of RNPOs for the financial year 2010. In order to quantify the information disclosed in the annual returns, partial disclosure indexes of basic information (BI) disclosure index, financial information (FI) disclosure index and governance information (GI) disclosure index have been built which takes into account the content of information items in the annual returns. The empirical evidence obtained revealed low disclosure practices among RNPOs in the sample. The multiple regression results showed that the organizational attribute of the board size appeared to be the most significant predictor for both partial index on the extent of BI disclosure index, and FI disclosure index. On the other hand, the extent of financial information disclosure is related to the amount of donation received by RNPOs. On GI disclosure index, the existence of an external audit appeared to be significant variable. This study has contributed to the academic literature in providing empirical evidence of the disclosure practices among RNPOs.Keywords: disclosure, index, partial, NPOs, religious
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18812680 Effect of Prandtl Number on Natural Convection Heat Transfer from a Heated Semi-Circular Cylinder
Authors: Avinash Chandra, R. P. Chhabra
Abstract:
Natural convection heat transfer from a heated horizontal semi-circular cylinder (flat surface upward) has been investigated for the following ranges of conditions; Grashof number, and Prandtl number. The governing partial differential equations (continuity, Navier-Stokes and energy equations) have been solved numerically using a finite volume formulation. In addition, the role of the type of the thermal boundary condition imposed at cylinder surface, namely, constant wall temperature (CWT) and constant heat flux (CHF) are explored. Natural convection heat transfer from a heated horizontal semi-circular cylinder (flat surface upward) has been investigated for the following ranges of conditions; Grashof number, and Prandtl number, . The governing partial differential equations (continuity, Navier-Stokes and energy equations) have been solved numerically using a finite volume formulation. In addition, the role of the type of the thermal boundary condition imposed at cylinder surface, namely, constant wall temperature (CWT) and constant heat flux (CHF) are explored. The resulting flow and temperature fields are visualized in terms of the streamline and isotherm patterns in the proximity of the cylinder. The flow remains attached to the cylinder surface over the range of conditions spanned here except that for and ; at these conditions, a separated flow region is observed when the condition of the constant wall temperature is prescribed on the surface of the cylinder. The heat transfer characteristics are analyzed in terms of the local and average Nusselt numbers. The maximum value of the local Nusselt number always occurs at the corner points whereas it is found to be minimum at the rear stagnation point on the flat surface. Overall, the average Nusselt number increases with Grashof number and/ or Prandtl number in accordance with the scaling considerations. The numerical results are used to develop simple correlations as functions of Grashof and Prandtl number thereby enabling the interpolation of the present numerical results for the intermediate values of the Prandtl or Grashof numbers for both thermal boundary conditions.Keywords: Constant heat flux, Constant surface temperature, Grashof number, natural convection, Prandtl number, Semi-circular cylinder
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 34162679 Salicylhydroxamic Acid Inhibits the Growth of Candida albicans
Authors: Shu-Ying Marissa Pang, Stephen Tristram, Simon Brown
Abstract:
Candida spp. are common and aggressive pathogens. Because of the growing resistance of Candida spp. to current antifungals, novel targets, found in Candida spp. but not in humans or other flora, have to be identified. The alternative oxidase (AOX) is one such possibility. This enzyme is insensitive to cyanide, but is sensitive to compounds such as salicylhydroxamic acid (SHAM), disulfiram and n-alkyl gallates. The growth Candida albicans was inhibited by SHAM (Ki = 9-15 mM) and cyanide (Ki = 2-4 mM), albeit to differing extents. The rate of O2 uptake was inhibited by less than 10% by 25 mM SHAM and by about 90% by 250 μM KCN. Although SHAM substantially inhibited the growth of C. albicans, it is unlikely that the inhibition of AOX was the cause. Salicylhydroxamic acid is used therapeutically in the treatment of urinary tract infections and urolithiasis, but it also has some potential in the treatment of C. albicans infection.Keywords: alternative oxidase, Candida albicans, growth, respiration, salicylhydroxamic acid.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25942678 Impact of Modeling Different Fading Channels on Wireless MAN Fixed IEEE802.16d OFDM System with Diversity Transmission Technique
Authors: Shanar Askar, Shahzad Memon, LachhmanDas, MSKalhoro
Abstract:
Wimax (Worldwide Interoperability for Microwave Access) is a promising technology which can offer high speed data, voice and video service to the customer end, which is presently, dominated by the cable and digital subscriber line (DSL) technologies. The performance assessment of Wimax systems is dealt with. The biggest advantage of Broadband wireless application (BWA) over its wired competitors is its increased capacity and ease of deployment. The aims of this paper are to model and simulate the fixed OFDM IEEE 802.16d physical layer under variant combinations of digital modulation (BPSK, QPSK, and 16-QAM) over diverse combination of fading channels (AWGN, SUIs). Stanford University Interim (SUI) Channel serial was proposed to simulate the fixed broadband wireless access channel environments where IEEE 802.16d is to be deployed. It has six channel models that are grouped into three categories according to three typical different outdoor Terrains, in order to give a comprehensive effect of fading channels on the overall performance of the system.Keywords: WIMAX, OFDM, Additive White Gaussian Noise, Fading Channel, SUI, Doppler Effect.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21382677 Evolution, Tendencies and Impact of Standardization of Input/Output Platforms in Full Scale Simulators for Training Power Plant Operators
Authors: Zabre Eric, Román Rafael
Abstract:
This article presents the evolution and technological changes implemented on the full scale simulators developed by the Simulation Department of the Instituto de Investigaciones Eléctricas1 (Mexican Electric Research Institute) and located at different training centers around the Mexican territory, and allows US to know the last updates, basically from the input/output view point, of the current simulators at some facilities of the electrical sector as well as the compatible industry of the electrical manufactures and industries such as Comision Federal de Electricidad (CFE*, The utility Mexican company). Tendencies of these developments and impact within the operators- scope are also presented.
Keywords: Control room, communication protocol, instructor console, modeling, controller, training simulator
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13732676 Leatherback Turtle (Dermochelys coriacea) after Incubation Eggshell in Andaman Sea, Thailand Study: Microanalysis on Ultrastructure and Elemental Composition
Authors: M. Areekijseree, M. Pumipaiboon, S. Nuamsukon, K. Kittiwattanawong, C. Thongchai, S. Sikiwat, T. Chuen-Im
Abstract:
There are few studies on eggshell of leatherback turtle which is endangered species in Thailand. This study was focusing on the ultrastructure and elemental composition of leatherback turtle eggshells collected from Andaman Sea Shore, Thailand during the nesting season using scanning electron microscope (SEM). Three eggshell layers of leatherback turtle; the outer cuticle layer or calcareous layer, the middle layer or middle multistrata layer and the inner fibrous layer were recognized. The outer calcareous layer was thick and porosity which consisted of loose nodular units of various crystal shapes and sizes. The loose attachment between these units resulted in numerous spaces and openings. The middle layer was compact thick with several multistrata and contained numerous openings connecting to both outer cuticle layer and inner fibrous layer. The inner fibrous layer was compact and thin, and composed of numerous reticular fibers. Energy dispersive X-ray microanalysis detector revealed energy spectrum of X-rays character emitted from all elements on each layer. The percentages of all elements were found in the following order: carbon (C) > oxygen (O) > calcium (Ca) > sulfur (S) > potassium (K) > aluminum (Al) > iodine (I) > silicon (Si) > chlorine (Cl) > sodium (Na) > fluorine (F) > phosphorus (P) > magnesium (Mg). Each layer consisted of high percentage of CaCO3 (approximately 98%) implying that it was essential for turtle embryonic development. A significant difference was found in the percentages of Ca and Mo in the 3layers. Moreover, transition metal, metal and toxic non-metal contaminations were found in leatherback turtle eggshell samples. These were palladium (Pd), molybdenum (Mo), copper (Cu), aluminum (Al), lead (Pb), and bromine (Br). The contamination elements were seen in the outer layers except for Mo. All elements were readily observed and mapped using Smiling program. X-ray images which mapped the location of all elements were showed. Calcium containing in the eggshell appeared in high contents and was widely distributing in clusters of the outer cuticle layer to form CaCO3 structure. Moreover, the accumulation of Na and Cl was observed to form NaCl which was widely distributing in 3 eggshell layers. The results from this study would be valuable on assessing the emergent success in this endangered species.
Keywords: Leatherback turtle (Dermochelys coriacea), SEM (SEI/EDX), turtle eggshell.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19942675 Use of Life Cycle Data for Condition-Oriented Maintenance
Authors: M. Winkens, M. Goerke, P. Nyhuis
Abstract:
This technical contribution treats of a novel approach to condition-oriented maintenance as elaborated by Collaborative Research Centre 653 at the Leibniz University in Hanover. The objective resides in the targeted analysis of information about a component's lifecycle for maintenance purposes. The information in question is collected by means of the Collaborative Research Centre's innovative technologies. This enables preventive maintenance of components on the basis of their condition. This contribution initially explains condition-oriented maintenance, before introducing the Collaborative Research Centre and finally presenting the methodology for analyzing the information. The current state of development is described and an outlook provided for expanding the methodology.
Keywords: Gentelligent Components, Preventive Maintenance, life cycle data.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17742674 Simulation Games in Business Process Management Education
Authors: Vesna Bosilj Vuksic, Mirjana Pejic Bach
Abstract:
Business process management (BPM) has become widely accepted within business community as a means for improving business performance. However, it is of the highest importance to incorporate BPM as part of the curriculum at the university level education in order to achieve the appropriate acceptance of the method. Goal of the paper is to determine the current state of education in business process management (BPM) at the Croatian universities and abroad. It investigates the applied forms of instruction and teaching methods and gives several proposals for BPM courses improvement. Since majority of undergraduate and postgraduate students have limited understanding of business processes and lack of any practical experience, there is a need for introducing new teaching approaches. Therefore, we offer some suggestions for further improvement, among which the introduction of simulation games environment in BPM education is strongly recommended.Keywords: business process management, simulation games, education
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 40462673 The Investigations of Water-ethanol Mixture by Monte Carlo Method
Authors: Atamas N. A., Atamas A. A.
Abstract:
Energetic and structural results for ethanol-water mixtures as a function of the mole fraction were calculated using Monte Carlo methodology. Energy partitioning results obtained for equimolar water-ethanol mixture and ether organic liquids are compared. It has been shown that at xet=0.22 the RDFs for waterethanol and ethanol-ethanol interactions indicated strong hydrophobic interactions between ethanol molecules and the local structure of solution is less structured at this concentration as at ether ones. Results obtained for ethanol-water mixture as a function of concentration are in good agreement with the experimental data.
Keywords: Ethanol, molecular liquids, Monte Carlo, water, thermodynamics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2243