Search results for: controlled balanced boolean function
3450 Performance Comparison of Droop Control Methods for Parallel Inverters in Microgrid
Authors: Ahmed Ismail, Mustafa Baysal
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Although the energy source in the world is mainly based on fossil fuels today, there is a need for alternative energy generation systems, which are more economic and environmentally friendly, due to continuously increasing demand of electric energy and lacking power resources and networks. Distributed Energy Resources (DERs) such as fuel cells, wind and solar power have recently become widespread as alternative generation. In order to solve several problems that might be encountered when integrating DERs to power system, the microgrid concept has been proposed. A microgrid can operate both grid connected and island mode to benefit both utility and customers. For most distributed energy resources (DER) which are connected in parallel in LV-grid like micro-turbines, wind plants, fuel cells and PV cells electrical power is generated as a direct current (DC) and converted to an alternative currents (AC) by inverters. So the inverters are assumed to be primary components in a microgrid. There are many control techniques of parallel inverters to manage active and reactive sharing of the loads. Some of them are based on droop method. In literature, the studies are usually focused on improving the transient performance of inverters. In this study, the performance of two different controllers based on droop control method is compared for the inverters operated in parallel without any communication feedback. For this aim, a microgrid in which inverters are controlled by conventional droop controller and modified droop controller is designed. Modified controller is obtained by adding PID into conventional droop control. Active and reactive power sharing performance, voltage and frequency responses of those control methods are measured in several operational cases. Study cases have been simulated by MATLAB-SIMULINK.Keywords: active and reactive power sharing, distributed generation, droop control, microgrid
Procedia PDF Downloads 5943449 The Treatment Effect of Turmeric (Curcuma domestica Val.) Rhizome Extract to Reduce Serum Transaminase Level on Paracetamol Induced Liver Toxicity in Wistar White Male Rats (Rattus norvegicus)
Authors: David Tanujaya Kurniawan
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Background: Liver injury caused by paracetamol is marked by increased serum transaminase levels. Turmeric is a local herb that is available in large quantities and inexpensive in contradiction to its substantial benefits, including its potency to increase glutathione production and regenerate hepatocyte into normal condition. Aim: The aim of this study was to analyze the potencial treatment effect of turmeric rhizome extract to reduce serum transaminase level on paracetamol induced liver toxicity in rats. Methods: This study was a laboratory experimental research with post-test only controlled group design. A group of 24 Wistar white male rats was induced with paracetamol 360 mg/kg body weight for 10 days. The group was then separated into four groups: the first and the second was treated with 100 mg/kg body weight and 150 mg/kg body weight of turmeric rhizome extract, subsequently, the third as positive control was given 27 mg/kg body weight of lesichol, while the fourth as negative control was given CMC-Na 1%. Each of this treatment was given for seven days. At the end of the study, the blood samples were taken to measure SGOT and SGPT levels. The one-way Anova test revealed significant difference in mean of SGPT level (p=0,001). The LSD test showed significant differences of SGPT levels in both treatment groups and negative control group. However, there was no sgnificant difference between positive control and both treatment groups. Conclusion: Curcuma domestica Val. rhizome extract could not reduce SGOT level, but it reduced SGPT level significantly.Keywords: Curcuma domestica val., SGOT, SGPT, paracetamol, liver toxicity
Procedia PDF Downloads 4013448 The Stability Study of Large-Scale Grid-Tied Photovoltaic System Containing Different Types of Inverter
Authors: Chen Zheng, Lin Zhou, Bao Xie, Xiao Du, Nianbin Shao
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Power generated by large-scale photovoltaic plants (LSPVPs) is usually transmitted to the grid through several transformers and long distance overhead lines. Impedance of transformers and transmission lines results in complex interactions between the plant and the grid and among different inverters. In accordance with the topological structure of LSPV in reality, an equivalent model containing different inverters was built and then interactions between the plant and the grid and among different inverters were studied. Based on the vector composition principle of voltage at the point of common coupling (PCC), the mathematic function of PCC voltage in regard to the total power and grid impedance was deduced, from which the uttermost total power to guarantee the system stable is obtained. Taking the influence of different inverters numbers and the length of transmission lines to the system stability into account, the stability criterion of LSPV containing different inverters was derived. The result of simulation validated the theory analysis in the paper.Keywords: LSPVPs, stability analysis, grid impedance, different types of inverter, PCC voltage
Procedia PDF Downloads 3113447 Processing and Characterization of Cereal Bar Containing Cassava Flour
Authors: E. L. Queiroz, S. M. A. Souza, R. T. S. Santos
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The cereal bars have emerged as a healthy alternative in the food sector, by presenting a remarkable functional appeal, being a product of high nutritional value. Cereals have an important function in feeding because they have features that particularize them as their variety, smooth flavour and aroma and easy digestion and absorption in the body. Brazil is the largest producer of cassava in the world, and the flour produced from this raw material is a source of nutrients for much of the low-income population, however it is little explored industrially. The northeast region of Brazil has great potential for honey production, which is a source of vitamins, proteins, minerals and organic acids but it is much used as a medicine. Aiming to combine the production of healthy food with the sustainable utilization and enhancement of family farming products, was created a cereal bar using regional raw materials of desirable nutritional characteristics: honey, umbu pulp and cassava flour. The cereal bar was characterized by physicochemical analyzes quantifying the content of lipids, proteins, moisture and ashes, microbiological and sensory evaluation showed that the cereal bar is a safe, and nutritious food with good sensory properties.Keywords: cassava flour, cereal bar, honey, insoluble fibre
Procedia PDF Downloads 4733446 Development of Automatic Farm Manure Spreading Machine for Orchards
Authors: Barış Ozluoymak, Emin Guzel, Ahmet İnce
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Since chemical fertilizers are used for meeting the deficiency of plant nutrients, its many harmful effects are not taken into consideration for the structure of the earth. These fertilizers are hampering the work of the organisms in the soil immediately after thrown to the ground. This interference is first started with a change of the soil pH and micro organismic balance is disrupted by reaction in the soil. Since there can be no fragmentation of plant residues, organic matter in the soil will be increasingly impoverished in the absence of micro organismic living. Biological activity reduction brings about a deterioration of the soil structure. If the chemical fertilization continues intensively, soils will get worse every year; plant growth will slow down and stop due to the intensity of chemical fertilizers, yield decline will be experienced and farmer will not receive an adequate return on his investment. In this research, a prototype of automatic farm manure spreading machine for orange orchards that not just manufactured in Turkey was designed, constructed, tested and eliminate the human drudgery involved in spreading of farm manure in the field. The machine comprised several components as a 5 m3 volume hopper, automatic controlled hydraulically driven chain conveyor device and side delivery conveyor belts. To spread the solid farm manure automatically, the machine was equipped with an electronic control system. The hopper and side delivery conveyor designs fitted between orange orchard tree row spacing. Test results showed that the control system has significant effects on reduction in the amount of unnecessary solid farm manure use and avoiding inefficient manual labor.Keywords: automatic control system, conveyor belt application, orchard, solid farm manure
Procedia PDF Downloads 2883445 The Effects on Abomasal Emtying Rate of Erythromycin and Bethanechol in Healthy, Premature and Diarrheic Calves
Authors: Sebnem Canikli Engin, Mutlu Sevinc, Hasan Guzelbektes
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In this study, we aim to define the effects of erythromycin and bethanechol which are prokinetic agents, on the value of abomasal discharge in healthy, diarrhea and premature calves. In the work, 5 healty calves, 12 diarrheaic calves and 12 premature calves, amounting to a total of 29 calves. In healty calves work; the same 5 calves were used for controlled, erythromycin and bethanechol studies (there was a 48-hour waiting period between each work). In diarrheic calves work; 12 diarrheic calves were used during the study (4 of them for control group, 4 of them bethanechol group and last 4 calves erythromycin group). In premature calves works; 12 premature calves were used during the study (4 of them for control group, 4 of them bethanechol group and last 4 calves erythromycin group). 10 mg/kg IM dose of erythromycin were applied to each erythromycin group, 0,07 mg/kg IM dose of bethanechol were applied on bethanechol group. No drugs were applied to the control group and substitution milk was given to all calves. 50 mg/kg acetominophen and 25 gram/L glucose have been added into the substitution milk to evaluate the speed of gastrointestinal motility with the test results of absorptions of acetominophen and glucose. The blood samples have been taken before substitution milk application and 30, 60, 90, 120, 180, 240 and 300 minutes after substitution milk application. Respiratory rates and number of heartbeats were also recorded during the test time. No changes were observed in the number of heartbeats, respiratory rates and general conditions for all groups after drug application. It is observed that, the feces of some calves became slightly watery and viscous and premature calves generaly defecated after 180 minutes. When Cmax, Tmax and AUC values of acetaminophen and glucose are compared with control group’s after applying erythromycin on the calves in the premature group, we obtain higher Cmax (P<0,05), shorter Tmax and greather AUC (P>0,05) values. In conclusion, according to clinical and laboratory findings, it may be stated that the application of 10 mg/kg doze of erythromycin IM has provided faster abomazal emptying in premature calves.Keywords: abomazal emptying, bethanechol, calf, erythromycin
Procedia PDF Downloads 3393444 The Analysis of Changes in Urban Hierarchy of Isfahan Province in the Fifty-Year Period (1956-2006)
Authors: Hamidreza Joudaki, Yousefali Ziari
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The appearance of city and urbanism is one of the important processes which have affected social communities. Being industrialized urbanism developed along with each other in the history. In addition, they have had simple relationship for more than six thousand years, that is, from the appearance of the first cities. In 18th century by coming out of industrial capitalism, progressive development took place in urbanism in the world. In Iran, the city of each region made its decision by itself and the capital of region (downtown) was the only central part and also the regional city without any hierarchy, controlled its realm. However, this method of ruling during these three decays, because of changing in political, social and economic issues that have caused changes in rural and urban relationship. Moreover, it has changed the variety of performance of cities and systematic urban network in Iran. Today, urban system has very vast imbalanced apace and performance. In Isfahan, the trend of urbanism is like the other part of Iran and systematic urban hierarchy is not suitable and normal. This article is a quantitative and analytical. The statistical communities are Isfahan Province cities and the changes in urban network and its hierarchy during the period of fifty years (1956 -2006) has been surveyed. In addition, those data have been analyzed by model of Rank and size and Entropy index. In this article Iran cities and also the factor of entropy of primate city and urban hierarchy of Isfahan Province have been introduced. Urban residents of this Province have been reached from 55 percent to 83% (2006). As we see the analytical data reflects that there is mismatching and imbalance between cities. Because the entropy index was.91 in 1956.And it decreased to.63 in 2006. Isfahan city is the primate city in the whole of these periods. Moreover, the second and the third cities have population gap with regard to the other cities and finally, they do not follow the system of rank-size.Keywords: urban network, urban hierarchy, primate city, Isfahan province, urbanism, first cities
Procedia PDF Downloads 2613443 Deep Learning for SAR Images Restoration
Authors: Hossein Aghababaei, Sergio Vitale, Giampaolo Ferraioli
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In the context of Synthetic Aperture Radar (SAR) data, polarization is an important source of information for Earth's surface monitoring. SAR Systems are often considered to transmit only one polarization. This constraint leads to either single or dual polarimetric SAR imaging modalities. Single polarimetric systems operate with a fixed single polarization of both transmitted and received electromagnetic (EM) waves, resulting in a single acquisition channel. Dual polarimetric systems, on the other hand, transmit in one fixed polarization and receive in two orthogonal polarizations, resulting in two acquisition channels. Dual polarimetric systems are obviously more informative than single polarimetric systems and are increasingly being used for a variety of remote sensing applications. In dual polarimetric systems, the choice of polarizations for the transmitter and the receiver is open. The choice of circular transmit polarization and coherent dual linear receive polarizations forms a special dual polarimetric system called hybrid polarimetry, which brings the properties of rotational invariance to geometrical orientations of features in the scene and optimizes the design of the radar in terms of reliability, mass, and power constraints. The complete characterization of target scattering, however, requires fully polarimetric data, which can be acquired with systems that transmit two orthogonal polarizations. This adds further complexity to data acquisition and shortens the coverage area or swath of fully polarimetric images compared to the swath of dual or hybrid polarimetric images. The search for solutions to augment dual polarimetric data to full polarimetric data will therefore take advantage of full characterization and exploitation of the backscattered field over a wider coverage with less system complexity. Several methods for reconstructing fully polarimetric images using hybrid polarimetric data can be found in the literature. Although the improvements achieved by the newly investigated and experimented reconstruction techniques are undeniable, the existing methods are, however, mostly based upon model assumptions (especially the assumption of reflectance symmetry), which may limit their reliability and applicability to vegetation and forest scenarios. To overcome the problems of these techniques, this paper proposes a new framework for reconstructing fully polarimetric information from hybrid polarimetric data. The framework uses Deep Learning solutions to augment hybrid polarimetric data without relying on model assumptions. A convolutional neural network (CNN) with a specific architecture and loss function is defined for this augmentation problem by focusing on different scattering properties of the polarimetric data. In particular, the method controls the CNN training process with respect to several characteristic features of polarimetric images defined by the combination of different terms in the cost or loss function. The proposed method is experimentally validated with real data sets and compared with a well-known and standard approach from the literature. From the experiments, the reconstruction performance of the proposed framework is superior to conventional reconstruction methods. The pseudo fully polarimetric data reconstructed by the proposed method also agree well with the actual fully polarimetric images acquired by radar systems, confirming the reliability and efficiency of the proposed method.Keywords: SAR image, polarimetric SAR image, convolutional neural network, deep learnig, deep neural network
Procedia PDF Downloads 743442 Software Engineering Inspired Cost Estimation for Process Modelling
Authors: Felix Baumann, Aleksandar Milutinovic, Dieter Roller
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Up to this point business process management projects in general and business process modelling projects in particular could not rely on a practical and scientifically validated method to estimate cost and effort. Especially the model development phase is not covered by a cost estimation method or model. Further phases of business process modelling starting with implementation are covered by initial solutions which are discussed in the literature. This article proposes a method of filling this gap by deriving a cost estimation method from available methods in similar domains namely software development or software engineering. Software development is regarded as closely similar to process modelling as we show. After the proposition of this method different ideas for further analysis and validation of the method are proposed. We derive this method from COCOMO II and Function Point which are established methods of effort estimation in the domain of software development. For this we lay out similarities of the software development rocess and the process of process modelling which is a phase of the Business Process Management life-cycle.Keywords: COCOMO II, busines process modeling, cost estimation method, BPM COCOMO
Procedia PDF Downloads 4443441 Study of Parameters Influencing Dwell Times for Trains
Authors: Guillaume Craveur
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The work presented here shows a study on several parameters identified as influencing dwell times for trains. Three kinds of rolling stocks are studied for this project and the parameters presented are the number of passengers, the allocation of passengers, their priorities, the platform station height, the door width and the train design. In order to make this study, a lot of records have been done in several stations in Paris (France). Then, in order to study these parameters, numerical simulations are completed. The goal is to quantify the impact of each parameter on the dwelling times. For example, this study highlights the impact of platform height and the presence of steps between the platform and the train. Three types of station platforms are concerned by this study : ‘optimum’ station platform which is 920 mm high, standard station platform which is 550 mm high, and high station platform which is 1150 mm high and different kinds of steps exist in order to fill these gaps. To conclude, this study shows the impact of these parameters on dwell times and their impact in function of the size of population.Keywords: dwell times, numerical tools, rolling stock, platforms
Procedia PDF Downloads 3373440 Development the Potential of Parking Tax and Parking Retribution Revenues: Case Study in Bekasi City
Authors: Ivan Yudianto
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The research objectives are to analyze the factors that impede the Parking Tax and Parking Retribution collection in Bekasi City Government, analyzing the factors that can increase local own revenue from the tax sector of parking tax and parking retribution, analyze monitoring the parking retribution collection by the Bekasi City Government, analyze strategies Bekasi City Government through the preparation of a roadmap and action plan to increase parking tax and parking retribution revenues. The approach used in this research is a qualitative approach. Qualitative research is used because the problem is not yet clear and the object to be studied will be holistic, complex, and dynamic, and the relationship will be interactive symptoms. Methods of data collection and technical analysis of the data was in-depth interviews, participant observation, documentary materials, literature, and triangulation, as well as new methods such as the methods of visual materials and internet browsing. The results showed that there are several factors that become an obstacle such as the parking taxpayer does not disclose the actual parking revenue, the parking taxpayer are late or do not pay Parking Tax, many parking locations controlled by illegal organizations, shortage of human resources in charge levy and supervise the parking tax and parking retribution collection in the Bekasi City Government, surveillance parking tax and parking retribution are not scheduled on a regular basis. Several strategic priorities in order to develop the potential of the Parking Tax and Parking Retribution in the Bekasi City Government, namely through increased controling and monitoring of the Parking Taxpayer, forming a team of auditors to audit the Parking Taxpayer, seek law enforcement persuasive and educative to reduce Parking Taxpayer wayward, providing strict sanctions against the Parking Taxpayer disobedient, revised regulations mayors about locations of parking in Bekasi City, rationalize revenues target of Parking Retribution, conducting takeover attempts parking location on the roadside of the individual or specific group, and drafting regional regulations on parking subscribe.Keywords: local own revenue, parking retribution, parking tax, parking taxpayer
Procedia PDF Downloads 3293439 Experimental Research on the Effect of Activating Temperature on Combustion and Nox Emission Characteristics of Pulverized Coal in a Novel Purification-combustion Reaction System
Authors: Ziqu Ouyang, Kun Su
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A novel efficient and clean coal combustion system, namely the purification-combustion system, was designed by the Institute of Engineering Thermal Physics, Chinese Academy of Science, in 2022. Among them, the purification system was composed of a mesothermal activating unit and a hyperthermal reductive unit, and the combustion system was composed of a mild combustion system. In the purification-combustion system, the deep in-situ removal of coal-N could be realized by matching the temperature and atmosphere in each unit, and thus the NOx emission was controlled effectively. To acquire the methods for realizing the efficient and clean coal combustion, this study investigated the effect of the activating temperature (including 822 °C, 858 °C, 933 °C, 991 °C), which was the key factor affecting the system operation, on combustion and NOx emission characteristics of pulverized coal in a 30 kW purification-combustion test bench. The research result turned out that the activating temperature affected the combustion and NOx emission characteristics significantly. As the activating temperature increased, the temperature increased first and then decreased in the mild combustion unit, and the temperature change in the lower part was much higher than that in the upper part. Moreover, the main combustion region was always located at the top of the unit under different activating temperatures, and the combustion intensity along the unit was weakened gradually. Increasing the activating temperature excessively could destroy the reductive atmosphere early in the upper part of the unit, which wasn’t conducive to the full removal of coal-N in the reductive coal char. As the activating temperature increased, the combustion efficiency increased first and then decreased, while the NOx emission decreased first and then increased, illustrating that increasing the activating temperature properly promoted the efficient and clean coal combustion, but there was a limit to its growth. In this study, the optimal activating temperature was 858 °C. Hence, this research illustrated that increasing the activating temperature properly could realize the mutual matching of improving the combustion efficiency and reducing the NOx emission, and thus guaranteed the clean and efficient coal combustion well.Keywords: activating temperature, combustion characteristics, nox emission, purification-combustion system
Procedia PDF Downloads 963438 The Effect of the Combination of Methotrexate Nanoparticles and TiO2 on Breast Cancer
Authors: Nusaiba Al-Nemrawi, Belal Al-Husein
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Methotrexate (MTX) is a stoichiometric inhibitor of dihydrofolate reductase, which is essential for DNA synthesis. MTX is a chemotherapeutic agent used for treating many types of cancer cells. However, cells’ resistant to MTX is very common and its pharmacokinetic behavior is highly problematic. of MTX within tumor cells, we propose encapsulation of antitumor drugs in nanoparticulated systems. Chitosan (CS) is a naturally occurring polymer that is biocompatibe, biodegradable, non-toxic, cationic and bioadhesive. CS nanoparticles (CS-NPs) have been used as drug carrier for targeted delivery. Titanium dioxide (TiO2), a natural mineral oxide, which is used in biomaterials due to its high stability and antimicrobial and anticorrosive properties. TiO2 showed a potential as a tumor suppressor. In this study a new formulation of MTX loaded in CS NPs (CS-MTX NPs) and coated with Titanium oxide (TiO2) was prepared. The mean particle size, zeta potential, polydispersity index were measured. The interaction between CS NPs and TiO2 NPs was confirmed using FTIR and XRD. CS-MTX NPs was studied in vitro using the tumor cell line MCF-7 (human breast cancer). The results showed that CS-MTX has a size around 169 nm and as they were coated with TiO2, the size ranged between and depending on the ratio of CS-MTX to TiO2 ratio used in the preparation. All NPs (uncoated and coated carried positive charges and were monodispersed. The entrapment efficacy was around 65%. Both FTIR and XRD proved that TiO2 interacted with CS-MTX NPs. The drug invitro release was controlled and sustained over days. Finally, the studied in vitro using the tumor cell line MCF-7 suggested that combining nanomaterials with anticancer drugs CS-MTX NPs may be more effective than free MTX for cancer treatment. In conclusion, the combination of CS-MTX NPs and TiO2 NPs showed excellent time-dependent in vitro antitumor behavior, therefore, can be employed as a promising anticancer agent to attain efficient results towards MCF-7 cells.Keywords: Methotrexate, Titanium dioxide, Chitosan nanoparticles, cancer
Procedia PDF Downloads 1013437 Effects of Two Cross Focused Intense Laser Beams On THz Generation in Rippled Plasma
Authors: Sandeep Kumar, Naveen Gupta
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Terahertz (THz) generation has been investigated by beating two cosh-Gaussian laser beams of the same amplitude but different wavenumbers and frequencies through rippled collisionless plasma. The ponderomotive force is operative which is induced due to the intensity gradient of the laser beam over the cross-section area of the wavefront. The electrons evacuate towards a low-intensity regime, which modifies the dielectric function of the medium and results in cross focusing of cosh-Gaussian laser beams. The evolution of spot size of laser beams has been studied by solving nonlinear Schrodinger wave equation (NLSE) with variational technique. The laser beams impart oscillations to electrons which are enhanced with ripple density. The nonlinear oscillatory motion of electrons gives rise to a nonlinear current density driving THz radiation. It has been observed that the periodicity of the ripple density helps to enhance the THz radiation.Keywords: rippled collisionless plasma, cosh-gaussian laser beam, ponderomotive force, variational technique, nonlinear current density
Procedia PDF Downloads 2063436 Rotor Dynamic Analysis for a Shaft Train by Using Finite Element Method
Authors: M. Najafi
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In the present paper, a large turbo-generator shaft train including a heavy-duty gas turbine engine, a coupling, and a generator is established. The method of analysis is based on finite element simplified model for lateral and torsional vibration calculation. The basic elements of rotor are the shafts and the disks which are represented as circular cross section flexible beams and rigid body elements, respectively. For more accurate results, the gyroscopic effect and bearing dynamics coefficients and function of rotation are taken into account, and for the influence of shear effect, rotor has been modeled in the form of Timoshenko beam. Lateral critical speeds, critical speed map, damped mode shapes, Campbell diagram, zones of instability, amplitudes, phase angles response due to synchronous forces of excitation and amplification factor are calculated. Also, in the present paper, the effect of imbalanced rotor and effects of changing in internal force and temperature are studied.Keywords: rotor dynamic analysis, finite element method, shaft train, Campbell diagram
Procedia PDF Downloads 1373435 Seismic Assessment of Old Existing RC Buildings with Masonry Infill in Madinah as Per ASCE
Authors: Tarek M. Alguhane, Ayman H. Khalil, Nour M. Fayed, Ayman M. Ismail
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An existing RC building in Madinah is seismically evaluated with and without infill wall. Four model systems have been considered i. e. model I (no infill), model IIA (strut infill-update from field test), model IIB (strut infill- ASCE/SEI 41) and model IIC (strut infill-Soft storey-ASCE/SEI 41). Three dimensional pushover analyses have been carried out using SAP 2000 software incorporating inelastic material behavior for concrete, steel and infill walls. Infill wall has been modeled as equivalent strut according to suggested equation matching field test measurements and to the ASCE/SEI 41 equation. The effect of building modeling on the performance point as well as capacity and demand spectra due to EQ design spectrum function in Madinah area has been investigated. The response modification factor (R) for the 5 story RC building is evaluated from capacity and demand spectra (ATC-40) for the studied models. The results are summarized and discussed.Keywords: infill wall, pushover analysis, response modification factor, seismic assessment
Procedia PDF Downloads 3943434 Damage Mesomodel Based Low-Velocity Impact Damage Analysis of Laminated Composite Structures
Authors: Semayat Fanta, P.M. Mohite, C.S. Upadhyay
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Damage meso-model for laminates is one of the most widely applicable approaches for the analysis of damage induced in laminated fiber-reinforced polymeric composites. Damage meso-model for laminates has been developed over the last three decades by many researchers in experimental, theoretical, and analytical methods that have been carried out in micromechanics as well as meso-mechanics analysis approaches. It has been fundamentally developed based on the micromechanical description that aims to predict the damage initiation and evolution until the failure of structure in various loading conditions. The current damage meso-model for laminates aimed to act as a bridge between micromechanics and macro-mechanics of the laminated composite structure. This model considers two meso-constituents for the analysis of damage in ply and interface that imparted from low-velocity impact. The damages considered in this study include fiber breakage, matrix cracking, and diffused damage of the lamina, and delamination of the interface. The damage initiation and evolution in laminae can be modeled in terms of damaged strain energy density using damage parameters and the thermodynamic irreversible forces. Interface damage can be modeled with a new concept of spherical micro-void in the resin-rich zone of interface material. The damage evolution is controlled by the damage parameter (d) and the radius of micro-void (r) from the point of damage nucleation to its saturation. The constitutive martial model for meso-constituents is defined in a user material subroutine VUMAT and implemented in ABAQUS/Explicit finite element modeling tool. The model predicts the damages in the meso-constituents level very accurately and is considered the most effective technique of modeling low-velocity impact simulation for laminated composite structures.Keywords: mesomodel, laminate, low-energy impact, micromechanics
Procedia PDF Downloads 2273433 Interesting Behavior of Non-Thermal Plasma Photonic Crystals
Authors: A. Mousavi, S. Sadegzadeh
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In this research, the effect of non-thermal micro plasma with non-Maxwellian distribution function on the one dimensional plasma photonic crystals containing alternate plasma-dielectric layers, has been studied. By using Kronig Penny model, the dispersion relation of electromagnetic modes for such a periodic structure is obtained. In this study we take two plasma photonic crystals with different dielectric layers: the first one with Silicon monoxide named PPCI, and the second one with Tellurium dioxide named PPCII. The effects of the plasma layer thickness and the material of the dielectric layer on the plasma photonic crystal band gaps have been illustrated in the dispersion relation and the group velocity figures. Results revealed that in such a system, the non-thermal plasma exerts stronger limit on the wave’s propagation. In another word, for the non-thermal plasma photonic crystals (NPPC), there are two distinct regions in the dispersion plot. The upper region consists of alternate band gaps in such a way that both width and length of the bands decrease gradually as the band gaps order increases. Whereas in the lower region where v_ph > 20 c (for PPCI), waves will not be allowed to propagate.Keywords: band gap, dispersion relation, non-thermal plasma, plasma photonic crystal
Procedia PDF Downloads 5423432 Planning for Enviromental and Social Sustainability in Coastal Areas: A Case of Alappad
Authors: K. Vrinda
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Coastal ecosystems across the world are facing a lot of challenges due to natural phenomena as well as from uncontrolled human interventions. Here, Alappad, a coastal island situated in Kerala, India is undergoing significant damage and is gradually losing its environmental and social sustainability. The area is blessed with very rare and precious black mineral sand deposits. Sand mining for these minerals started in 1911 and is still continuing. But, unfortunately all the problems that Alappad faces now, have its root on mining of this mineral sand. The land area is continuously diminishing due to sea erosion. The mining has also caused displacement of people and environmental degradation. Marine life also is getting affected by mining on beach and pollution. The inhabitants are fishermen who are largely dependent on the eco-system for a living. So loss of environmental sustainability subsequently affects social sustainability too. Now the damage has reached a point beyond which our actions may not be able to make any impact. This was one of the most affected areas of the 2004 tsunami and the environmental degradation has further increased the vulnerability. So this study focuses on understanding the concerns related to the resource utilization, environment and the indigenous community staying there, and on formulating suitable strategies to restore the sustainability of the area. An extensive study was conducted on site, to find out the physical, social, and economical characteristics of the area. A focus group discussion with the inhabitants shed light on different issues they face in their day-to-day life. The analysis of all these data, led to the formation of a new development vision for the area which focuses on environmental restoration and socio-economic development while allowing controlled exploitation of resources. A participatory approach is formulated which enables these three aspects through community based programs.Keywords: Community development, Disaster resilience, Ecological restoration, Environmental sustainability, Social-environmental planning, Social Sustainability
Procedia PDF Downloads 1133431 Brain Stem Posterior Reversible Encephalopathy Syndrome in Nephrotic Syndrome
Authors: S. H. Jang
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Posterior reversible encephalopathy syndrome (PRES) is characterized by acute neurologic symptoms (visual loss, headache, altered mentality and seizures) and by typical imaging findings (bilateral subcortical and cortical edema with predominatly posterior distribution). Nephrotic syndrome is a syndrome comprising signs of proteinuria, hypoalbuminemia, and edema. It is well known that hypertension predispose patient with nephrotic syndrome to PRES. A 45-year old male was referred for suddenly developed vertigo, disequilibrium. He had previous history of nephrotic syndrome. His medical history included diabetes controlled with medication. He was hospitalized because of generalized edema a few days ago. His vital signs were stable. On neurologic examination, his mental state was alert. Horizontal nystagmus to right side on return to primary position was observed. He showed good grade motor weakness and ataxia in right upper and lower limbs without other sensory abnormality. Brain MRI showed increased signal intensity in FLAIR image, decreased signal intensity in T1 image and focal enhanced lesion in T1 contrast image at whole midbrain, pons and cerebellar peduncle symmetrically, which was compatible with vasogenic edema. Laboratory findings showed severe proteinuria and hypoalbuminemia. He was given intravenous dexamethasone and diuretics to reduce vasogenic edema and raise the intra-vascular osmotic pressure. Nystagmus, motor weakness and limb ataxia improved gradually over 2 weeks; He recovered without any neurologic symptom and sign. Follow-up MRI showed decreased vasogenic edema fairly. We report a case of brain stem PRES in normotensive, nephrotic syndrome patient.Keywords: posterior reversible encephalopathy syndrome, MRI, nephrotic syndrome, vasogenic brain edema
Procedia PDF Downloads 2783430 Effect of vr Based Wii Fit Training on Muscle Strength, Sensory Integration Ability and Walking Abilities in Patients with Parkinson's Disease: A Randomized Control Trial
Authors: Ying-Yi Laio, Yea-Ru Yang, Yih-Ru Wu, Ray-Yau Wang
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Background: Virtual reality (VR) systems are proved to increase motor performance in stroke and elderly. However, the effects have not been established in patients with Parkinson’s disease (PD). Purpose: To examine the effects of VR based training in improving muscle strength, sensory integration ability and walking abilities in patients with PD by a randomized controlled trial. Method: Thirty six participants with diagnosis of PD were randomly assigned to one of the three groups (n=12 for each group). Participants received VR-based Wii Fit exercise (VRWii group) or traditional exercise (TE group) for 45 minutes, followed by treadmill training for another 15 minutes for 12 sessions in 6 weeks. Participants in the control group received no structured exercise program but fall-prevention education. Outcomes included lower extremity muscle strength, sensory integration ability, walking velocity, stride length, and functional gait assessment (FGA). All outcomes were assessed at baseline, after training and at 1-month follow-up. Results: Both VRWii and TE groups showed more improvement in level walking velocity, stride length, FGA, muscle strength and vestibular system integration than control group after training and at 1-month follow-up. The VRWii training, but not the TE training, resulted in more improvement in visual system integration than the control. Conclusions: VRWii training is as beneficial as traditional exercise in improving walking abilities, sensory integration ability and muscle strength in patients with PD, and such improvements persisted at least for 1 month. The VRWii training is then suggested to be implemented in patients with PD.Keywords: virtual reality, walking, sensory integration, muscle strength, Parkinson’s disease
Procedia PDF Downloads 3333429 A Near-Optimal Domain Independent Approach for Detecting Approximate Duplicates
Authors: Abdelaziz Fellah, Allaoua Maamir
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We propose a domain-independent merging-cluster filter approach complemented with a set of algorithms for identifying approximate duplicate entities efficiently and accurately within a single and across multiple data sources. The near-optimal merging-cluster filter (MCF) approach is based on the Monge-Elkan well-tuned algorithm and extended with an affine variant of the Smith-Waterman similarity measure. Then we present constant, variable, and function threshold algorithms that work conceptually in a divide-merge filtering fashion for detecting near duplicates as hierarchical clusters along with their corresponding representatives. The algorithms take recursive refinement approaches in the spirit of filtering, merging, and updating, cluster representatives to detect approximate duplicates at each level of the cluster tree. Experiments show a high effectiveness and accuracy of the MCF approach in detecting approximate duplicates by outperforming the seminal Monge-Elkan’s algorithm on several real-world benchmarks and generated datasets.Keywords: data mining, data cleaning, approximate duplicates, near-duplicates detection, data mining applications and discovery
Procedia PDF Downloads 3903428 Experimental Modal Analysis of Reinforced Concrete Square Slabs
Authors: M. S. Ahmed, F. A. Mohammad
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The aim of this paper is to perform experimental modal analysis (EMA) of reinforced concrete (RC) square slabs. EMA is the process of determining the modal parameters (Natural Frequencies, damping factors, modal vectors) of a structure from a set of frequency response functions FRFs (curve fitting). Although experimental modal analysis (or modal testing) has grown steadily in popularity since the advent of the digital FFT spectrum analyzer in the early 1970’s, studying all members and materials using such method have not yet been well documented. Therefore, in this work, experimental tests were conducted on RC square specimens (0.6m x 0.6m with 40 mm). Experimental analysis is based on freely supported boundary condition. Moreover, impact testing as a fast and economical means of finding the modes of vibration of a structure was used during the experiments. In addition, Pico Scope 6 device and MATLAB software were used to acquire data, analyze and plot Frequency Response Function (FRF). The experimental natural frequencies which were extracted from measurements exhibit good agreement with analytical predictions. It is showed that EMA method can be usefully employed to perform the dynamic behavior of RC slabs.Keywords: natural frequencies, mode shapes, modal analysis, RC slabs
Procedia PDF Downloads 4123427 Polymersomes in Drug Delivery: A Comparative Review with Liposomes and Micelles
Authors: Salma E. Ahmed
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Since the mid 50’s, enormous attention has been paid towards nanocarriers and their applications in drug and gene delivery. Among these vesicles, liposomes and micelles have been heavily investigated due to their many advantages over other types. Liposomes, for instance, are mostly distinguished by their ability to encapsulate hydrophobic, hydrophilic and amphiphilic drugs. Micelles, on the other hand, are self-assembled shells of lipids, amphiphilic or oppositely charged block copolymers that, once exposed to aqueous media, can entrap hydrophobic agents, and possess prolonged circulation in the bloodstream. Both carriers are considered compatible and biodegradable. Nevertheless, they have limited stabilities, chemical versatilities, and drug encapsulation efficiencies. In order to overcome these downsides, strategies for optimizing a novel drug delivery system that has the architecture of liposomes and polymeric characteristics of micelles have been evolved. Polymersomes are vehicles with fluidic cores and hydrophobic shells that are protected and isolated from the aqueous media by the hydrated hydrophilic brushes which give the carrier its distinctive polymeric bilayer shape. Similar to liposomes, this merit enables the carrier to encapsulate a wide range of agents, despite their affinities and solubilities in water. Adding to this, the high molecular weight of the amphiphiles that build the body of the polymersomes increases their colloidal and chemical stabilities and reduces the permeability of the polymeric membranes, which makes the vesicles more protective to the encapsulated drug. These carriers can also be modified in ways that make them responsive when targeted or triggered, by manipulating their composition and attaching moieties and conjugates to the body of the carriers. These appealing characteristics, in addition to the ease of synthesis, gave the polymersomes greater potentials in the area of drug delivery. Thus, their design and characterization, in comparison with liposomes and micelles, are briefly reviewed in this work.Keywords: controlled release, liposomes, micelles, polymersomes, targeting
Procedia PDF Downloads 1993426 Classification of Echo Signals Based on Deep Learning
Authors: Aisulu Tileukulova, Zhexebay Dauren
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Radar plays an important role because it is widely used in civil and military fields. Target detection is one of the most important radar applications. The accuracy of detecting inconspicuous aerial objects in radar facilities is lower against the background of noise. Convolutional neural networks can be used to improve the recognition of this type of aerial object. The purpose of this work is to develop an algorithm for recognizing aerial objects using convolutional neural networks, as well as training a neural network. In this paper, the structure of a convolutional neural network (CNN) consists of different types of layers: 8 convolutional layers and 3 layers of a fully connected perceptron. ReLU is used as an activation function in convolutional layers, while the last layer uses softmax. It is necessary to form a data set for training a neural network in order to detect a target. We built a Confusion Matrix of the CNN model to measure the effectiveness of our model. The results showed that the accuracy when testing the model was 95.7%. Classification of echo signals using CNN shows high accuracy and significantly speeds up the process of predicting the target.Keywords: radar, neural network, convolutional neural network, echo signals
Procedia PDF Downloads 3573425 Circadian-Clock Controlled Drug Transport Across Blood-Cerebrospinal Fluid Barrier
Authors: André Furtado, Rafael Mineiro, Isabel Gonçalves, Cecília Santos, Telma Quintela
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The development of therapies for central nervous system (CNS) disorders is one of the biggest challenges of current pharmacology, given the unique features of brain barriers, which limit drug delivery. Efflux transporters (ABC transporters) expressed at the blood-cerebrospinal fluid barrier (BCSFB), are the main obstacles for the delivery of therapeutic compounds into the CNS, compromising the effective treatment of brain cancer, brain metastasis from peripheral cancers, or even neurodegenerative disorders. It is thus extremely important to understand the regulation of these transporters for reducing their expression while treating a brain disorder or choosing the most appropriate conditions for drug administration. Based on the fact that the BCSFB have fine-tuned biological rhythms, studying the circadian variation of drug transport processes is critical for choosing the most appropriate time of the day for drug administration. In our study, using an in vitro model of the BCSFB, we characterized the circadian transport profile of methotrexate (MTX) and donepezil (DNPZ), two drugs involved in the treatment of cancer and Alzheimer’s Disease symptoms, respectively. We found that MTX is transported across the basal and apical membranes of the BCSFB in a circadian way. The circadian pattern of an ABC transporter, Abcc4, might be partially responsible for MTX circadian transport. Furthermore, regarding the DNPZ transport study, we observed that the regulation of Abcg2 expression by the circadian rhythm will impact the circadian-dependent transport of DNPZ across the BCSFB. Overall, our results will contribute to the current knowledge on brain pharmacoresistance at the BCSFB by disclosing how circadian rhythms control drug delivery to the brain, setting the grounds for a potential application of chronotherapy to brain diseases to enhance the efficacy of medications and minimize their side effects.Keywords: blood-cerebrospinal fluid barrier, ABC transporters, drug transport, chronotherapy
Procedia PDF Downloads 213424 Adjustments of Mechanical and Hydraulic Properties of Wood Formed under Environmental Stresses
Authors: B. Niez, B. Moulia, J. Dlouha, E. Badel
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Trees adjust their development to the environmental conditions they experience. Storms events of last decades showed that acclimation of trees to mechanical stresses due to wind is a very important process that allows the trees to sustain for long years. In the future, trees will experience new wind patterns, namely, more often strong winds and fewer daily moderate winds. Moreover, these patterns will go along with drought periods that may interact with the capacity of trees to adjust their growth to mechanical stresses due to wind. It is necessary to understand the mechanisms of wood functional acclimations to environmental conditions in order to predict their behaviour and in order to give foresters and breeders the relevant tools to adapt their forest management. This work aims to study how trees adjust the mechanical and hydraulic functions of their wood to environmental stresses and how this acclimation may be beneficial for the tree to resist to future stresses. In this work, young poplars were grown under controlled climatic conditions that include permanent environmental stress (daily mechanical stress of the stem by bending and/or hydric stress). Then, the properties of wood formed under these stressed conditions were characterized. First, hydraulic conductivity and sensibility to cavitation were measured at the tissue level in order to evaluate the changes in water transport capacity. Secondly, bending tests and Charpy impact tests were carried out at the millimetric scale to locally measure mechanical parameters such as elastic modulus, elastic limit or rupture energy. These experimental data allow evaluating the impacts of mechanical and water stress on the wood material. At the stem level, they will be merged in an integrative model in order to evaluate the beneficial aspect of wood acclimation for trees.Keywords: acclimation, environmental stresses, hydraulics, mechanics, wood
Procedia PDF Downloads 2063423 Flexural Response of Glass Fiber Reinforced Polymer Sandwich Panels with 3D Woven Honeycomb Core
Authors: Elif Kalkanli, Constantinos Soutis
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The use of textile preform in the advanced fields including aerospace, automotive and marine has exponentially grown in recent years. These preforms offer excellent advantages such as being lightweight and low-cost, and also, their suitability for creating different fiber architectures with different materials whilst improved mechanical properties in certain aspects. In this study, a novel honeycomb core is developed by a 3Dweaving process. The assembly of the layers is achieved thanks to innovative weaving design. Polyester yarn is selected for the 3D woven honeycomb core (3DWHC). The core is used to manufacture a sandwich panel with 2x2 twill glass fiber composite face sheets. These 3DWHC sandwich panels will be tested in three-point bending. The in-plane and out-of-plane (through-the-thickness) mechanical response of the core will be examined as a function of cell size in addition to the flexural response of the sandwich panel. The failure mechanisms of the core and the sandwich skins will be reported in addition to flexural strength and stiffness. Possible engineering applications will be identified.Keywords: 3D woven, assembly, failure modes, honeycomb sandwich panel
Procedia PDF Downloads 2113422 Proposing an Index for Determining Key Knowledge Management Processes in Decision Making Units Using Fuzzy Quality Function Deployment (QFD), Data Envelopment Analysis (DEA) Method
Authors: Sadegh Abedi, Ali Yaghoubi, Hamidreza Mashatzadegan
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This paper proposes an approach to identify key processes required by an organization in the field of knowledge management and aligning them with organizational objectives. For this purpose, first, organization’s most important non-financial objectives which are impacted by knowledge management processes are identified and then, using a quality house, are linked with knowledge management processes which are regarded as technical elements. Using this method, processes that are in need of improvement and more attention are prioritized based on their significance. This means that if a process has more influence on organization’s objectives and is in a dire situation comparing to others, is prioritized for choice and improvement. In this research process dominance is considered to be an influential element in process ranking (in addition to communication matrix). This is the reason for utilizing DEA techniques for prioritizing processes in quality house. Results of implementing the method in Khuzestan steel company represents this method’s capability of identifying key processes that require improvements in organization’s knowledge management system.Keywords: knowledge management, organizational performance, fuzzy data, envelopment analysis
Procedia PDF Downloads 4223421 Incorporation of Growth Factors onto Hydrogels via Peptide Mediated Binding for Development of Vascular Networks
Authors: Katie Kilgour, Brendan Turner, Carly Catella, Michael Daniele, Stefano Menegatti
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In vivo, the extracellular matrix (ECM) provides biochemical and mechanical properties that are instructional to resident cells to form complex tissues with characteristics to develop and support vascular networks. In vitro, the development of vascular networks can be guided by biochemical patterning of substrates via spatial distribution and display of peptides and growth factors to prompt cell adhesion, differentiation, and proliferation. We have developed a technique utilizing peptide ligands that specifically bind vascular endothelial growth factor (VEGF), erythropoietin (EPO), or angiopoietin-1 (ANG1) to spatiotemporally distribute growth factors to cells. This allows for the controlled release of each growth factor, ultimately enhancing the formation of a vascular network. Our engineered tissue constructs (ETCs) are fabricated out of gelatin methacryloyl (GelMA), which is an ideal substrate for tailored stiffness and bio-functionality, and covalently patterned with growth factor specific peptides. These peptides mimic growth factor receptors, facilitating the non-covalent binding of the growth factors to the ETC, allowing for facile uptake by the cells. We have demonstrated in the absence of cells the binding affinity of VEGF, EPO, and ANG1 to their respective peptides and the ability for each to be patterned onto a GelMA substrate. The ability to organize growth factors on an ETC provides different functionality to develop organized vascular networks. Our results demonstrated a method to incorporate biochemical cues into ETCs that enable spatial and temporal control of growth factors. Future efforts will investigate the cellular response by evaluating gene expression, quantifying angiogenic activity, and measuring the speed of growth factor consumption.Keywords: growth factor, hydrogel, peptide, angiogenesis, vascular, patterning
Procedia PDF Downloads 167