Search results for: field control
4384 CACSC tool for Automatic Design of Robust Controllers for Hydropower Plants
Authors: Jose J.CarreñoZagarra, Rodolfo Villamizar Mejía
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This work describes a CACSD tool for automatic design of robust controllers for hydraulic turbines. The tool calculates the optimal controller using the MATLAB hinfopt function and it serves as a practical and effective solution for the laborious task of designing a different controller for each type of turbine and generator, and different parameters and conditions of the plant. Results of the simulation of a generating unit subject to parameters variation show the accuracy and efficiency of the obtained robust controllers.Keywords: Robust Control, Hydroelectric System Turbine, Control H∞, CACSD
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15694383 The Accuracy of the Flight Derivative Estimates Derived from Flight Data
Authors: Jung-hoon Lee, Eung Tai Kim, Byung-hee Chang, In-hee Hwang, Dae-sung Lee
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The accuracy of estimated stability and control derivatives of a light aircraft from flight test data were evaluated. The light aircraft, named ChangGong-91, is the first certified aircraft from the Korean government. The output error method, which is a maximum likelihood estimation technique and considers measurement noise only, was used to analyze the aircraft responses measures. The multi-step control inputs were applied in order to excite the short period mode for the longitudinal and Dutch-roll mode for the lateral-directional motion. The estimated stability/control derivatives of Chan Gong-91 were analyzed for the assessment of handling qualities comparing them with those of similar aircraft. The accuracy of the flight derivative estimates derived from flight test measurement was examined in engineering judgment, scatter and Cramer-Rao bound, which turned out to be satisfactory with minor defects..Keywords: Light Aircraft, Flight Test, Accuracy, Engineering Judgment, Scatter, Cramer-Rao Bound
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19524382 An Impairment Sensitive and Reliable SR-ARQ Mechanism for Unreliable Feedback in GPRS
Authors: Mansab Ali, Muhammad Khalid Khan
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The advances in wireless communication have opened unlimited horizons but there are some challenges as well. The Nature derived air medium between MS (Mobile Station) and BS (Base Station) is beyond human control and produces channel impairment. The impact of the natural conditions at the air medium is the biggest issue in wireless communication. Natural conditions make reliability more cumbersome; here reliability refers to the efficient recovery of the lost or erroneous data. The SR-ARQ (Selective Repeat-Automatic Repeat Request) protocol is a de facto standard for any wireless technology at the air interface with its standard reliability features. Our focus in this research is on the reliability of the control or feedback signal of the SR-ARQ protocol. The proposed mechanism, RSR-ARQ (Reliable SR-ARQ) is an enhancement of the SR-ARQ protocol that has ensured the reliability of the control signals through channel impairment sensitive mechanism. We have modeled the system under two-state discrete time Markov Channel. The simulation results demonstrate the better recovery of the lost or erroneous data that will increase the overall system performance.
Keywords: ISR-ARQ, MAA, RSR-ARQ, SAA.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12414381 Automat Control of the Aircrafts- Lateral Movement using the Dynamic Inversion
Authors: Mihai Lungu, Romulus Lungu, Lucian Grigorie
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The paper presents a new system for the automat control of the aircrafts- flight in lateral plane using the cinematic model and the dynamic inversion. Starting from the equations of the aircrafts- lateral movement, the authors use two axes systems and obtained a control law that cancels the lateral deviation of the flying objects from the runway line. This system makes the aircrafts- direction angle to follow the direction angle of the runway line. Simulations in Matlab/Simulink have been done for different aircraft-s initial points and direction angles. The inconvenience of this system is the long duration of the “transient regime". That is why this system can be used independently, but the results are not very good; thus, it can be a part (subsystem) of other systems. The main system that cancels the lateral deviation from the runway line is based on dynamic inversion and uses, as subsystem, the control system for the lateral movement using the cinematic model. Using complex Matlab/Simulink models, the authors obtained the time evolution of the direction angle and the time evolution of the aircraft lateral deviation with respect to the runway line, for different values of the initial direction angle and for different wind types. The system has a very good behavior for all initial direction angles and wind types.Keywords: Direction angle, Dynamic inversion, Lateraldeviation, Lateral movement
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19384380 Comparative Dynamic Performance of Load Frequency Control of Nonlinear Interconnected Hydro-Thermal System Using Intelligent Techniques
Authors: Banaja Mohanty, Prakash Kumar Hota
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This paper demonstrates dynamic performance evaluation of load frequency control (LFC) with different intelligent techniques. All non-linearities and physical constraints have been considered in simulation studies such as governor dead band (GDB), generation rate constraint (GRC) and boiler dynamics. The conventional integral time absolute error has been considered as objective function. The design problem is formulated as an optimisation problem and particle swarm optimisation (PSO), bacterial foraging optimisation algorithm (BFOA) and differential evolution (DE) are employed to search optimal controller parameters. The superiority of the proposed approach has been shown by comparing the results with published fuzzy logic control (FLC) for the same interconnected power system. The comparison is done using various performance measures like overshoot, undershoot, settling time and standard error criteria of frequency and tie-line power deviation following a step load perturbation (SLP). It is noticed that, the dynamic performance of proposed controller is better than FLC. Further, robustness analysis is carried out by varying the time constants of speed governor, turbine, tie-line power in the range of +40% to -40% to demonstrate the robustness of the proposed DE optimized PID controller.Keywords: Automatic generation control, governor dead band, generation rate constraint, differential evolution.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10604379 Optimizing Performance of Tablet's Direct Compression Process Using Fuzzy Goal Programming
Authors: Abbas Al-Refaie
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This paper aims at improving the performance of the tableting process using statistical quality control and fuzzy goal programming. The tableting process was studied. Statistical control tools were used to characterize the existing process for three critical responses including the averages of a tablet’s weight, hardness, and thickness. At initial process factor settings, the estimated process capability index values for the tablet’s averages of weight, hardness, and thickness were 0.58, 3.36, and 0.88, respectively. The L9 array was utilized to provide experimentation design. Fuzzy goal programming was then employed to find the combination of optimal factor settings. Optimization results showed that the process capability index values for a tablet’s averages of weight, hardness, and thickness were improved to 1.03, 4.42, and 1.42, respectively. Such improvements resulted in significant savings in quality and production costs.
Keywords: Fuzzy goal programming, control charts, process capability, tablet optimization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10044378 Studying the Structural Behaviour of RC Beams with Circular Openings of Different Sizes and Locations Using FE Method
Authors: Ali Shubbar, Hasanain Alwan, Ee Yu Phur, John McLoughlin, Ameer Al-khaykan
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This paper aims to investigate the structural behaviour of RC beams with circular openings of different sizes and locations modelled using ABAQUS FEM software. Seven RC beams with the dimensions of 1200 mm×150 mm×150 mm were tested under three-point loading. Group A consists of three RC beams incorporating circular openings with diameters of 40 mm, 55 mm and 65 mm in the shear zone. However, Group B consists of three RC beams incorporating circular openings with diameters of 40 mm, 55 mm and 65 mm in the flexural zone. The final RC beam did not have any openings, to provide a control beam for comparison. The results show that increasing the diameter of the openings increases the maximum deflection and the ultimate failure load decreases relative to the control beam. In the shear zone, the presence of the openings caused an increase in the maximum deflection ranging between 4% and 22% and a decrease in the ultimate failure load of between 26% and 36% compared to the control beam. However, the presence of the openings in the flexural zone caused an increase in the maximum deflection of between 1.5% and 19.7% and a decrease in the ultimate failure load of between 6% and 13% relative to the control beam. In this study, the optimum location for placing circular openings was found to be in the flexural zone of the beam with a diameter of less than 30% of the depth of the beam.
Keywords: Ultimate failure load, maximum deflection, shear zone, flexural zone.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16114377 Managing Meat Safety at South African Abattoirs
Authors: R. Govender, D. Naidoo, E. M. Buys
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The importance of ensuring safe meat handling and processing practices has been demonstrated in global reports on food safety scares and related illness and deaths. This necessitated stricter meat safety control strategies. Today, many countries have regulated towards preventative and systematic control over safe meat processing at abattoirs utilizing the Hazard Analysis Critical Control Point (HACCP) principles. HACCP systems have been reported as effective in managing food safety risks, if correctly implemented. South Africa has regulated the Hygiene Management System (HMS) based on HACCP principles applicable to abattoirs. Regulators utilise the Hygiene Assessment System (HAS) to audit compliance at abattoirs. These systems were benchmarked from the United Kingdom (UK). Little research has been done them since inception as of 2004. This paper presents a review of the two systems, its implementation and comparison with HACCP. Recommendations are made for future research to demonstrate the utility of the HMS and HAS in assuring safe meat to consumers.Keywords: Abattoir, co-regulation, food safety, HACCP, meat hygiene.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 70014376 Multi Task Scheme to Monitor Multivariate Environments Using Artificial Neural Network
Authors: K. Atashgar
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When an assignable cause(s) manifests itself to a multivariate process and the process shifts to an out-of-control condition, a root-cause analysis should be initiated by quality engineers to identify and eliminate the assignable cause(s) affected the process. A root-cause analysis in a multivariate process is more complex compared to a univariate process. In the case of a process involved several correlated variables an effective root-cause analysis can be only experienced when it is possible to identify the required knowledge including the out-of-control condition, the change point, and the variable(s) responsible to the out-of-control condition, all simultaneously. Although literature addresses different schemes to monitor multivariate processes, one can find few scientific reports focused on all the required knowledge. To the best of the author’s knowledge this is the first time that a multi task model based on artificial neural network (ANN) is reported to monitor all the required knowledge at the same time for a multivariate process with more than two correlated quality characteristics. The performance of the proposed scheme is evaluated numerically when different step shifts affect the mean vector. Average run length is used to investigate the performance of the proposed multi task model. The simulated results indicate the multi task scheme performs all the required knowledge effectively.
Keywords: Artificial neural network, Multivariate process, Statistical process control, Change point.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16814375 In vitro Control of Aedes aegypti Larvae Using Beauveria bassiana
Authors: R. O. B. Bitencourt, F. S. Farias, M. C. Freitas, C. J. R. Balduino, E.S. Mesquita, A. R. C. Corval, P. S. Gôlo, E. G. Pontes, V. R. E. P. Bittencourt, I. C. Angelo
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Aedes aegypti larval survival rate was assessed after exposure to blastopores or conidia (mineral oil-in-water formulation or aqueous suspension) of Beauveria bassiana CG 479 propagules (blastospores or conidia). Here, mineral oil was used in the fungal formulation to control Aedes aegypti larvae. 1%, 0.5% or 0.1% mineral oil-in-water solutions were used to evaluate mineral oil toxicity for mosquito larvae. In the oil toxicity test, 0.1% mineral oil solution reduced only 4.5% larval survival; accordingly, this concentration was chosen for fungal oil-in-water formulations. Aqueous suspensions were prepared using 0.01% Tween 80® in sterile dechlorinated water. A. aegypti larvae (L2) were exposed in aqueous suspensions or mineral oil-in-water fungal formulations at 1×107 propagules mL-1; the survival rate (assessed daily, for 7 days) and the median survival time (S50) were calculated. Seven days after the treatment, mosquito larvae survival rates were 8.56%, 16.22%, 58%, and 42.56% after exposure to oil-in-water blastospores, oil-in-water conidia, blastospores aqueous suspension and conidia aqueous suspension (respectively). Larvae exposed to 0.01% Tween 80® had 100% survival rate and the ones treated with 0.1% mineral oil-in-water had 95.11% survival rate. Larvae treated with conidia (regardless the presence of oil) or treated with blastospores formulation had survival median time (S50) ranging from one to two days. S50 was not determined (ND) when larvae were exposed to blastospores aqueous suspension, 0.01% Tween 80® (aqueous control) or 0.1% mineral oil-in-water formulation (oil control). B. bassiana conidia and blastospores (mineral oil-in-water formulated or suspended in water) had potential to control A. aegypti mosquito larvae, despite mineral oil-in-water formulation yielded better results in comparison to aqueous suspensions. Here, B. bassiana CG 479 isolate is suggested as a potential biocontrol agent of A. aegypti mosquito larvae.
Keywords: Blastospores, formulation, mosquitoes, conidia.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9304374 International Service Learning 3.0: Using Technology to Improve Outcomes and Sustainability
Authors: Anthony Vandarakis
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Today’s International Service Learning practices require an update: modern technologies, fresh educational frameworks, and a new operating system to accountably prosper. This paper describes a model of International Service Learning (ISL), which combines current technological hardware, electronic platforms, and asynchronous communications that are grounded in inclusive pedagogy. This model builds on the work around collaborative field trip learning, extending the reach to international partnerships across continents. Mobile technology, 21st century skills and summit-basecamp modeling intersect to support novel forms of learning that tread lightly on fragile natural ecosystems, affirm local reciprocal partnership in projects, and protect traveling participants from common yet avoidable cultural pitfalls.Keywords: International Service Learning, ISL, field experiences, mobile technology, ‘out there in here’, summit basecamp pedagogy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5624373 Value from Environmental and Cultural Perspectives or Two Sides of the Same Coin
Authors: Vilém Pařil, Dominika Tóthová
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This paper discusses the value theory in cultural heritage and the value theory in environmental economics. Two economic views of the value theory are compared, within the field of cultural heritage maintenance and within the field of the environment. The main aims are to find common features in these two differently structured theories under the layer of differently defined terms as well as really differing features of these two approaches; to clear the confusion which stems from different terminology as in fact these terms capture the same aspects of reality; and to show possible inspiration these two perspectives can offer one another. Another aim is to present these two value systems in one value framework. First, important moments of the value theory from the economic perspective are presented, leading to the marginal revolution of (not only) the Austrian School. Then the theory of value within cultural heritage and environmental economics are explored. Finally, individual approaches are compared and their potential mutual inspiration searched for.
Keywords: Cultural heritage, environmental economics, existence value, value theory.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18934372 Personnel Marketing as Perceived by HR Managers in Czech Republic: Results of a Qualitative Research Study
Authors: Lukáš Mazánek, Zdeňka Konečná
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The article is devoted to the area of personnel marketing. A comprehensive review of scientific literature and articles published predominantly in personnel-oriented journals was carried out, followed by a qualitative exploratory research with the aim to explore and explain the perception of personnel marketing. Due to the lack of research in this field in Czech Republic, we have focused on Czech HR managers, more specifically, on how they understand the tasks of personnel marketing, which tools they use and whether the companies they work for try to be a preferred employer. The answers from our respondents were used to help us determine what is important within this field. All of the respondents strive to be a preferred employer and try to achieve it by using an extensive range of marketing tools. The most frequently used tools are advertising, job fairs presentations, employee care and employer brand promotion.
Keywords: Czech Republic, personnel marketing, preferred employer, qualitative research study.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12224371 Modeling and Simulations of Surface Plasmon Waveguide Structures
Authors: Moussa Hamdan, Abdulati Abdullah
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This paper presents an investigation of the fabrication of the optical devices in terms of their characteristics based on the use of the electromagnetic waves. Planar waveguides are used to examine the field modes (bound modes) and the parameters required for this structure. The modifications are conducted on surface plasmons based waveguides. Simple symmetric dielectric slab structure is used and analyzed in terms of transverse electric mode (TE-Mode) and transverse magnetic mode (TM-Mode. The paper presents mathematical and numerical solutions for solving simple symmetric plasmons and provides simulations of surface plasmons for field confinement. Asymmetric TM-mode calculations for dielectric surface plasmons are also provided.Keywords: Surface plasmons, optical waveguides, semiconductor lasers, refractive index, slab dialectical.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16594370 A Field Research for Investigating the Effect of Strategic Management on Institutionalization Levels of Enterprises
Authors: Kemalettin Eryeşil, Aykut Bedük, Mehtap Fındık
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The aim of this study is to determine the effect of strategic management implementations on the institutionalization levels. In this regard a field study has been made over 31 stone quarry enterprises in cement producing sector in Konya by using survey method. In this study, institutionalization levels of the enterprises have been evaluated regarding three dimensions: professionalization, management approach, participation in decisions and delegation of authority. According to the results of the survey, there is a highly positive and statistically significant relationship between the strategic management implementations and institutionalization levels of the enterprises. Additionally,-considering the results of regression analysis made for establishing the relationship between strategic management and institutionalization levels- it has been determined that strategic management implementations of the enterprises can be used as a variable to explain the institutionalization levels of them, and also strategic management implementations of the enterprises increase the institutionalization levels of them.Keywords: Institutionalization, Management, Strategic Management.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20694369 A Study on Fuzzy Adaptive Control of Enteral Feeding Pump
Authors: Seungwoo Kim, Hyojune Chae, Yongrae Jung, Jongwook Kim
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Recent medical studies have investigated the importance of enteral feeding and the use of feeding pumps for recovering patients unable to feed themselves or gain nourishment and nutrients by natural means. The most of enteral feeding system uses a peristaltic tube pump. A peristaltic pump is a form of positive displacement pump in which a flexible tube is progressively squeezed externally to allow the resulting enclosed pillow of fluid to progress along it. The squeezing of the tube requires a precise and robust controller of the geared motor to overcome parametric uncertainty of the pumping system which generates due to a wide variation of friction and slip between tube and roller. So, this paper proposes fuzzy adaptive controller for the robust control of the peristaltic tube pump. This new adaptive controller uses a fuzzy multi-layered architecture which has several independent fuzzy controllers in parallel, each with different robust stability area. Out of several independent fuzzy controllers, the most suited one is selected by a system identifier which observes variations in the controlled system parameter. This paper proposes a design procedure which can be carried out mathematically and systematically from the model of a controlled system. Finally, the good control performance, accurate dose rate and robust system stability, of the developed feeding pump is confirmed through experimental and clinic testing.
Keywords: Enteral Feeding Pump, Peristaltic Tube Pump, Fuzzy Adaptive Control, Fuzzy Multi-layered Controller, Look-up Table..
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16454368 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 15034367 Adaptive Helmholtz Resonator in a Hydraulic System
Authors: Lari Kela
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An adaptive Helmholtz resonator was designed and adapted to hydraulics. The resonator was controlled by open- and closed-loop controls so that 20 dB attenuation of the peak-to-peak value of the pulsating pressure was maintained. The closed-loop control was noted to be better, albeit it was slower because of its low pressure and temperature variation, which caused variation in the effective bulk modulus of the hydraulic system. Low-pressure hydraulics contains air, which affects the stiffness of the hydraulics, and temperature variation changes the viscosity of the oil. Thus, an open-loop control loses its efficiency if a condition such as temperature or the amount of air changes after calibration. The instability of the low-pressure hydraulic system reduced the operational frequency range of the Helmholtz resonator when compared with the results of an analytical model. Different dampers for hydraulics are presented. Then analytical models of a hydraulic pipe and a hydraulic pipe with a Helmholtz resonator are presented. The analytical models are based on the wave equation of sound pressure. Finally, control methods and the results of experiments are presented.Keywords: adaptive, damper, hydraulics, pressure, pulsating
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 43424366 Antiinflammatory and Antinociceptive of Hydro Alcoholic Tanacetum balsamita L. Extract
Authors: S. Nasri, G. H. Amin, A. Azimi
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The use of herbs to treat disease is accompanied with the history of human life. This research is aimed to study the anti-inflammatory and antinociceptive effects of hydroalcoholic extract of aerial parts of "Tanacetum balsamita balsamita". In the experimental studies 144 male mice are used. In the inflammatory test, animals were divided into six groups: Control, positive control (receiving Dexamethason at dose of 15mg/kg), and four experimental groups receiving Tanacetum balsamita balsamita hydroalcoholic extract at doses of 25, 50, 100 and 200mg/kg. Xylene was used to induce inflammation. Formalin was used to study the nociceptive effects. Animals were divided into six groups: control group, positive control group (receiving morphine) and four experimental groups receiving Tanacetum balsamita balsamita (Tb.) hydroalcoholic extract at doses of 25, 50, 100 and 200mg/kg. I.p. injection of drugs or normal saline was performed 30 minutes before test. The data were analyzed by using one way Variance analysis and Tukey post test. Aerial parts of Tanacetum balsamita balsamita hydroalcoholic extract decreased significantly inflammatory at dose of 200mg/kg (P<0/001) and caused a significant decrease and alleviated the nociception in both first and second phases at doses of 200mg/kg (p<0/001) and 100mg/kg (P<0/05). Tanacetum balsamita balsamita extract has the anti-inflammatory and anti-nociceptive effects which seems to be related with flavonoids especially Quercetin.
Keywords: Inflammation, nociception, Hydroalcoholic extract, aerial parts of Tanacetum balsamita balsamita L.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20944365 Centralized Controller for Microgrid
Authors: Adel Hamad Rafa
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This paper, proposes a control system for use with microgrid consiste of multiple small scale embedded generation networks (SSEG networks) connected to the 33kV distribution network. The proposed controller controls power flow in the grid-connected mode of operation, enables voltage and frequency control when the SSEG networks are islanded, and resynchronises the SSEG networks with the utility before reconnecting them. The performance of the proposed controller has been tested in simulations using PSCAD.
Keywords: Microgrid, Small scale embedded generation, island mode, resynchronisation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20314364 The Theory and Practice of the State Model of Corporate Governance
Authors: Asaiel Alohaly
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A theoretical framework for corporate governance is needed to bridge the gap between the corporate governance of private companies and State-Owned Enterprises (SOEs). The two dominant models, being shareholder and stakeholder, do not always address the specific requirements and challenges posed by ‘hybrid’ companies; namely, previously national bodies that have been privatised while the government retains significant control or holds a majority of shares. Thus, an exploratory theoretical study is needed to identify how ‘hybrid’ companies should be defined and why the state model should be acknowledged since it is the less conspicuous model in comparison with the shareholder and stakeholder models. This research focuses on the state model of corporate governance to understand the complex ownership, control pattern, goals, and corporate governance of these hybrid companies. The significance of this research lies in the fact that there is a limited available publication on the state model. This research argues for the state model, which proceeds from an understanding of the institutionally embedded characteristics of hybrid companies, where the government as a shareholder, is either a majority of the total shares, or has been granted power based on the rule of law; the company bylaws.
Keywords: Corporate governance, control, shareholders, state model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13024363 Novel Nanomagnetic Beads Based - Latex Agglutination Assay for Rapid Diagnosis of Human Schistosomiasis Haematobium
Authors: Ibrahim Aly , Rabab Zalat, Bahaa EL Deen W. El Aswad, Ismail M. Moharm , Basam M. Masoud, Tarek Diab
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The objective of the present study was to evaluate the novel nanomagnetic beads based–latex agglutination assay (NMB-LAT) as a simple test for diagnosis of S. haematobium as well as standardize the novel nanomagnetic beads based –ELISA (NMB-ELISA). According to urine examination this study included 85 S. haematobium infected patients, 30 other parasites infected patients and 25 negative control samples. The sensitivity of novel NMB-LAT was 82.4% versus 96.5% and 88.2% for NMB-ELISA and currently used sandwich ELISA respectively. The specificity of NMB-LAT was 83.6% versus 96.3% and 87.3% for NMB-ELISA and currently used sandwich ELISA respectively. In conclusion, the novel NMB-ELISA is a valuable applicable diagnostic technique for diagnosis of human schistosomiasis haematobium. The novel NMB-ELISA assay is a suitable applicable diagnostic method in field survey especially when followed by ELISA as a confirmatory test in query false negative results. Trials are required to increase the sensitivity and specificity of NMB-ELISA assay.
Keywords: Diagnosis, Latex agglutination, Nanomagnetic beads, Sandwich ELISA.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 30994362 A Lossless Watermarking Based Authentication System For Medical Images
Authors: Samia Boucherkha, Mohamed Benmohamed
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In this paper we investigate the watermarking authentication when applied to medical imagery field. We first give an overview of watermarking technology by paying attention to fragile watermarking since it is the usual scheme for authentication.We then analyze the requirements for image authentication and integrity in medical imagery, and we show finally that invertible schemes are the best suited for this particular field. A well known authentication method is studied. This technique is then adapted here for interleaving patient information and message authentication code with medical images in a reversible manner, that is using lossless compression. The resulting scheme enables on a side the exact recovery of the original image that can be unambiguously authenticated, and on the other side, the patient information to be saved or transmitted in a confidential way. To ensure greater security the patient information is encrypted before being embedded into images.Keywords: Medical Imaging, Invertible Watermarking, Authentication, Integrity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26654361 Simulation of Dynamics of a Permanent Magnet Linear Actuator
Authors: Ivan Yatchev, Ewen Ritchie
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Comparison of two approaches for the simulation of the dynamic behaviour of a permanent magnet linear actuator is presented. These are full coupled model, where the electromagnetic field, electric circuit and mechanical motion problems are solved simultaneously, and decoupled model, where first a set of static magnetic filed analysis is carried out and then the electric circuit and mechanical motion equations are solved employing bi-cubic spline approximations of the field analysis results. The results show that the proposed decoupled model is of satisfactory accuracy and gives more flexibility when the actuator response is required to be estimated for different external conditions, e.g. external circuit parameters or mechanical loads.Keywords: Coupled problems, dynamic models, finite elementanalysis, linear actuators, permanent magnets.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27634360 Effect of Organic Matter and Biofertilizers on Chickpea Quality and Biological Nitrogen Fixation
Authors: Khosro Mohammadi, Amir Ghalavand, Majid Aghaalikhani
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In order to evaluation the effects of soil organic matter and biofertilizer on chickpea quality and biological nitrogen fixation, field experiments were carried out in 2007 and 2008 growing seasons. In this research the effects of different strategies for soil fertilization were investigated on grain yield and yield component, minerals, organic compounds and cooking time of chickpea. Experimental units were arranged in split-split plots based on randomized complete blocks with three replications. Main plots consisted of (G1): establishing a mixed vegetation of Vicia panunica and Hordeum vulgare and (G2): control, as green manure levels. Also, five strategies for obtaining the base fertilizer requirement including (N1): 20 t.ha-1 farmyard manure; (N2): 10 t.ha-1 compost; (N3): 75 kg.ha-1 triple super phosphate; (N4): 10 t.ha-1 farmyard manure + 5 t.ha-1 compost and (N5): 10 t.ha-1 farmyard manure + 5 t.ha-1 compost + 50 kg.ha-1 triple super phosphate were considered in sub plots. Furthermoree four levels of biofertilizers consisted of (B1): Bacillus lentus + Pseudomonas putida; (B2): Trichoderma harzianum; (B3): Bacillus lentus + Pseudomonas putida + Trichoderma harzianum; and (B4): control (without biofertilizers) were arranged in sub-sub plots. Results showed that integrating biofertilizers (B3) and green manure (G1) produced the highest grain yield. The highest amounts of yield were obtained in G1×N5 interaction. Comparison of all 2-way and 3-way interactions showed that G1N5B3 was determined as the superior treatment. Significant increasing of N, P2O5, K2O, Fe and Mg content in leaves and grains emphasized on superiority of mentioned treatment because each one of these nutrients has an approved role in chlorophyll synthesis and photosynthesis abilities of the crops. The combined application of compost, farmyard manure and chemical phosphorus (N5) in addition to having the highest yield, had the best grain quality due to high protein, starch and total sugar contents, low crude fiber and reduced cooking time.Keywords: chickpea, biofertilizer, nitrogen fixation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 33744359 Effect of Bio-Nitrogen as a Partial Alternative to Mineral-Nitrogen Fertiliser on Growth, Nitrate and Nitrite Contents, and Yield Quality in Brassica oleracea L.
Authors: Saad M. Howladar, Mostafa M. Rady, Ashraf Sh. Osman
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Effects of bio-nitrogen fertilizer (bio-N), as a partial alternative to mineral-nitrogen fertilizer (mineral-N), on growth, yield and yield quality of broccoli plants were investigated. Bio-N was applied at 1, 2 or 3 doses in combination with 65% of the recommended dose of mineral-N (bio-N1, bio-N2 or bio-N3 + ⅔mineral-N). However, 100% of the recommended dose of mineral- N was applied as a control. Significant positive influences of the bio- N3 + ⅔mineral-N treatment were observed on growth traits, leaf contents of nitrogen, phosphorus, potassium, nitrate and nitrite, and yield quality when compared to the other two combined treatments. In contrast, there were no significant differences in these parameters between the bio-N3 + ⅔mineral-N and the control treatments, except for leaf contents of nitrate and nitrite. They showed lower contents in the bio-N3 + ⅔mineral-N treatment than the control. Therefore, we recommend using bio-N as a partial alternative to mineral-N for healthy nutrition.
Keywords: Bio-fertilization, broccoli, growth, nitrate, nitrite, yield quality.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24844358 Electromagnetic Assessment of Submarine Power Cable Degradation Using Finite Element Method and Sensitivity Analysis
Authors: N. Boutra, N. Ravot, J. Benoit, O. Picon
Abstract:
Submarine power cables used for offshore wind farms electric energy distribution and transmission are subject to numerous threats. Some of the risks are associated with transport, installation and operating in harsh marine environment. This paper describes the feasibility of an electromagnetic low frequency sensing technique for submarine power cable failure prediction. The impact of a structural damage shape and material variability on the induced electric field is evaluated. The analysis is performed by modeling the cable using the finite element method, we use sensitivity analysis in order to identify the main damage characteristics affecting electric field variation. Lastly, we discuss the results obtained.Keywords: Electromagnetism, defect, finite element method, sensitivity analysis, submarine power cables.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10924357 Finite Element Prediction of Multi-Size Particulate Flow through Two-Dimensional Pump Casing
Authors: K. V. Pagalthivarthi, R. J. Visintainer
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Two-dimensional Eulerian (volume-averaged) continuity and momentum equations governing multi-size slurry flow through pump casings are solved by applying a penalty finite element formulation. The computational strategy validated for multi-phase flow through rectangular channels is adapted to the present study. The flow fields of the carrier, mixture and each solids species, and the concentration field of each species are determined sequentially in an iterative manner. The eddy viscosity field computed using Spalart-Allmaras model for the pure carrier phase is modified for the presence of particles. Streamline upwind Petrov-Galerkin formulation is used for all the momentum equations for the carrier, mixture and each solids species and the concentration field for each species. After ensuring mesh-independence of solutions, results of multi-size particulate flow simulation are presented to bring out the effect of bulk flow rate, average inlet concentration, and inlet particle size distribution. Mono-size computations using (1) the concentration-weighted mean diameter of the slurry and (2) the D50 size of the slurry are also presented for comparison with multi-size results.
Keywords: Eulerian-Eulerian model, Multi-size particulate flow, Penalty finite elements, Pump casing, Spalart-Allmaras.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14304356 Comparison of Statins Dose Intensity on HbA1c Control in Outpatients with Type 2 Diabetes: A Prospective Cohort Study
Authors: Mohamed A. Hammad, Dzul Azri Mohamed Noor, Syed Azhar Syed Sulaiman, Ahmed A. Khamis, Abeer Kharshid, Nor Azizah Aziz
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The effect of statins dose intensity (SDI) on glycemic control in patients with existing diabetes is unclear. Also, there are many contradictory findings were reported in the literature; thus, it is limiting the possibility to draw conclusions. This project was designed to compare the effect of SDI on glycated hemoglobin (HbA1c%) control in outpatients with Type 2 diabetes in the endocrine clinic at Hospital Pulau Pinang, Malaysia, between July 2015 and August 2016. A prospective cohort study was conducted, where records of 345 patients with Type 2 diabetes (Moderate-SDI group 289 patients and high-SDI cohort 56 patients) were reviewed to identify demographics and laboratory tests. The target of glycemic control (HbA1c < 7% for patient < 65 years, and < 8% for patient ≥ 65 years) was estimated, and the results were presented as descriptive statistics. From 289 moderate-SDI cohorts with a mean age of 57.3 ± 12.4 years, only 86 (29.8%) cases were shown to have controlled glycemia, while there were 203 (70.2%) cases with uncontrolled glycemia with confidence interval (CI) of 95% (6.2–10.8). On the other hand, the high-SDI group of 56 patients with Type 2 diabetes with a mean age 57.7±12.4 years is distributed among 11 (19.6%) patients with controlled diabetes, and 45 (80.4%) of them had uncontrolled glycemia, CI: 95% (7.1–11.9). The study has demonstrated that the relative risk (RR) of uncontrolled glycemia in patients with Type 2 diabetes that used high-SDI is 1.15, and the excessive relative risk (ERR) is 15%. The absolute risk (AR) is 10.2%, and the number needed to harm (NNH) is 10. Outpatients with Type 2 diabetes who use high-SDI of statin have a higher risk of uncontrolled glycemia than outpatients who had been treated with a moderate-SDI.
Keywords: Cohort study, diabetes control, dose intensity, HbA1c, Malaysia, statin, Type 2 diabetes mellitus, uncontrolled glycemia.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14634355 Possible Exposure of Persons with Cardiac Pacemakers to Extremely Low Frequency (ELF) Electric and Magnetic Fields
Authors: Leena Korpinen, Rauno Pääkkönen, Fabriziomaria Gobba, Vesa Virtanen
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The number of persons with implanted cardiac pacemakers (PM) has increased in Western countries. The aim of this paper is to investigate the possible situations where persons with a PM may be exposed to extremely low frequency (ELF) electric (EF) and magnetic fields (MF) that may disturb their PM. Based on our earlier studies, it is possible to find such high public exposure to EFs only in some places near 400 kV power lines, where an EF may disturb a PM in unipolar mode. Such EFs cannot be found near 110 kV power lines. Disturbing MFs can be found near welding machines. However, we do not have measurement data from welding. Based on literature and earlier studies at Tampere University of Technology, it is difficult to find public EF or MF exposure that is high enough to interfere with PMs.
Keywords: Cardiac Pacemaker, Electric Field, Magnetic Field.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2538