Search results for: single cell

Authors: Iqra Noor, Ihtzaz Qamar

Abstract:

Pitot-tube Jet pump, single-stage pump with low flow rate and high head, consists of a radial impeller that feeds water to rotating cavity. Water then enters stationary pitot-tube collector (diffuser), which discharges to the outside. By means of ANSYS Fluent 15.0, the internal flow characteristics for Pitot-tube Jet pump with standard pitot and curved pitot are studied. Under design condition, realizable k-e turbulence model and SIMPLEC algorithm are used to calculate 3D flow field inside both pumps. The simulation results reveal that energy is imparted to the flow by impeller and inside the rotor, forced vortex type flow is observed. Total pressure decreases inside pitot-tube whereas static pressure increases. Changing pitot-tube from standard to curved shape results in minimum flow circulation inside pitot-tube and leads to a higher pump performance.

Keywords: CFD, flow circulation, high pressure pump, impeller, internal flow, pickup tube pump, rectangle channels, rotating casing, turbulence

Procedia PDF Downloads 162

Authors: Mehdi Modabberifar, Sanaz Jabary, Mojtaba Ghodsi

Abstract:

Stiffness sensing is an important issue in medical diagnostic, robotics surgery, safe handling, and safe grasping of objects in production lines. Detecting and obtaining the characteristics in dwelling lumps embedded in a soft tissue and safe removing and handling of detected lumps is needed in surgery. Also in industry, grasping and handling an object without damaging in a place where it is not possible to access a human operator is very important. In this paper, a method for object handling is presented. It is based on the use of an intelligent gripper to detect the object stiffness and then setting a programmable force for grasping the object to move it. The main components of this system includes sensors (sensors for measuring force and displacement), electrical (electrical and electronic circuits, tactile data processing and force control system), mechanical (gripper mechanism and driving system for the gripper) and the display unit. The system uses a rotary potentiometer for measuring gripper displacement. A microcontroller using the feedback received by the load cell, mounted on the finger of the gripper, calculates the amount of stiffness, and then commands the gripper motor to apply a certain force on the object. Results of Experiments on some samples with different stiffness show that the gripper works successfully. The gripper can be used in haptic interfaces or robotic systems used for object handling.

Keywords: gripper, haptic, stiffness, robotic

Procedia PDF Downloads 362

Authors: Ishtiaq A. Chaudhry, Z. R. Tahir, F. A. Siddiqui, Z. Anwar, F. Valenzuelacalva

Abstract:

A series of experiments involving the particle image velocimetry technique are carried out to analyse the quantitative effectiveness of the synthesized vortical structures towards actual flow separation control. The streamwise vortices are synthesized from the synthetic jet actuator and introduced into the attached and separating boundary layer developed on the flat plate surface. Two types of actuators with different geometrical set up are used to analyse the evolution of vortical structures in the near wall region and their impact towards achieving separation delay on the actual aircraft wing. Firstly a single circular jet is synthesized at varying actuator operating parameters and issued into the boundary layer to evaluate the dynamics of the interaction between the vortical structures and the near wall low momentum fluid in the separated region. Secondly, an array of jets has been issued into the artificially separated region to assess the effectiveness of various vortical structures towards achieving the reattachment of the separated flow in the streamwise direction.

Keywords: boundary layer, flow separation, streamwise vortices, synthetic jet actuator

Procedia PDF Downloads 466

Authors: H. Loumi-Fergane, A. Belaidi

Abstract:

The problem of symmetries in field theory has been analyzed using geometric frameworks, such as the multisymplectic models by using in particular the multivector field formalism. In this paper, we expand the vector fields associated to infinitesimal symmetries which give rise to invariant quantities as Noether currents for classical field theories and relativistic mechanic using the multisymplectic geometry where the Poincaré-Cartan form has thus been greatly simplified using the Second Order Partial Differential Equation (SOPDE) for multi-vector fields verifying Euler equations. These symmetries have been classified naturally according to the construction of the fiber bundle used.  In this work, unlike other works using the analytical method, our geometric model has allowed us firstly to distinguish the angular moments of the gauge field obtained during different transformations while these moments are gathered in a single expression and are obtained during a rotation in the Minkowsky space. Secondly, no conditions are imposed on the Lagrangian of the mechanics with respect to its dependence in time and in qⁱ, the currents obtained naturally from the transformations are respectively the energy and the momentum of the system.

Keywords: conservation laws, field theories, multisymplectic geometry, relativistic mechanics

Procedia PDF Downloads 211

Authors: Dalia Jomehpour, Sara Sheikhlary, Esmaeil Heydari, Mohammad Hossien Majles Ara

Abstract:

In this study, we report fulvic acid-coated iron oxide nanoparticles of 10.7 ± 2.7 nm size, which serve to inhibit amyloid fibrillation formation. Although the effect of fulvic acid on tau fibrils was investigated, to our best knowledge, its inhibitory impacts on amyloid aggregation formation have been assessed neither in-vitro nor in-vivo. On the other hand, iron oxide nanoparticles exhibit anti-amyloid activity on their own. This study investigates the inhibitory effect of fulvic acid coated iron oxide nanoparticles on amyloid aggregations formed from the commonly used in-vitro model, lysozyme from chicken egg white. FESEM, XRD, and FTIR characterization confirmed that fulvic acid was coated onto the surface of the nanoparticles. The inhibitory effects of the fulvic acid coated iron oxide nanoparticles were verified by Thioflavin T assay, circular dichroism (CD), and FESEM analysis. Furthermore, the toxicity of the nanoparticles on the neuroblastoma SH-SY5Y human cell line was assessed through an MTT assay. Our results indicate that fulvic acid coated iron oxide nanoparticles can efficiently inhibit the formation of amyloid aggregations while exhibiting negligible in-vitro toxicity; thus, they can be used as anti-amyloid agents in the development of the potential drug for neurodegenerative diseases.

Keywords: Alzheimer’s disease, fulvic acid coated iron oxide nanoparticles, fulvic acid, amyloid inhibitor, polyphenols

Procedia PDF Downloads 119

Authors: Xiaojing Gao, James Njuguna

Abstract:

This paper emphasizes the importance of integrating project management and systems engineering for innovative system design and production development. The research highlights the need for a flexible approach that unifies these disciplines, as their isolation often leads to communication challenges and complexity within multidisciplinary teams. The paper aims to elucidate the intricate relationship between project management and systems engineering, recommending the consolidation of engineering disciplines into a single lifecycle for improved support of the design and development process. The research identifies a synergy between these disciplines, focusing on streamlining information communication during product design and development. The insights gained from this process can lead to product design optimization. Additionally, the paper introduces a proposed Project Management-Based Systems Engineering (PMBSE) framework, emphasizing effective communication, efficient processes, and advanced tools to enhance product development outcomes within the product lifecycle.

Keywords: system engineering, product design and development, project management, cross-disciplinary

Procedia PDF Downloads 83

Authors: Junichiro Kawaguchi

Abstract:

Space debris problems have emerged and threatened the use of low earth orbit around the Earth owing to a large number of spacecraft. In debris removal, a number of research and patents have been proposed and published so far. They assume servicing spacecraft, robots to be built for accessing the target debris objects. The robots should be sophisticated enough automatically to access the debris articulating the attitude and the translation motion with respect to the debris. This paper presents the idea of using the torpedo-like third unsophisticated and disposable body, in addition to the first body of the servicing robot and the second body of the target debris. The third body is launched from the first body from a distance farer than the size of the second body. This paper presents the method and the system, so that the third body is launched from the first body. The third body carries both a net and an inflatable or extendible drag deceleration device and is built small and light. This method enables even a micro to nano satellite to perform contactless and multiple debris removal even via a single flight.

Keywords: ballute, debris removal, echo satellite, gossamer, gun-net, inflatable space structure, small satellite, un-cooperated target

Procedia PDF Downloads 129

Authors: Felyppe Blum Goncalves, Juliana Sebastiany

Abstract:

In line with Brazilian legislation on the inclusion of persons with disabilities in the world of work, known as the 'quota law' (Law 8213/91) and in accordance with the prerogatives of the United Nations Convention on Human Rights of people with disabilities, which was ratified by Brazil through Federal Decree No. 6.949 of August 25, 2009, the SESI National Department, through Working Groups, structured the product Affordable Industry. This methodology aims to prepare the industries for the adequate process of inclusion of people with disabilities, as well as the development of an organizational culture that values and respects human diversity. All industries in Brazil with 100 or more employees must comply with current legislation, but due to the lack of information and guidance on the subject, they end up having difficulties in this process. The methodology brings solutions for companies through the professional qualification of the disabled person, preparation of managers, training of human resources teams and employees. It also advocates the survey of the architectural accessibility of the factory and the identification of the possibilities of inclusion of people with disabilities, through the compatibility between work and job requirements, preserving safety, health, and quality of life.

Keywords: inclusion, app, disability, management

Procedia PDF Downloads 166

Authors: Bo Hyun Kim, Sarng Woo Karng

Abstract:

In constructing a hydrogen refueling station, minimizing the volume and reducing the number of banks enable lessening the construction cost. This study aims at performing the dynamic simulation on 250 kg/day of a refueling station for light-duty vehicles. The primary compressor boosts hydrogen from a tube trailer of 250 to 480 bar and stores it in a medium-pressure bank. Then, additional compression of hydrogen from 480 to 900 bar is carried out and stored in a high-pressure bank. Economic analysis was conducted considering the amount of electricity consumed by compression corresponding to the volume and the number of banks (cascade system) in charging mode. NIST REFPROP was selected as the equation of state on the ASPEN HYSYS for thermodynamic analysis of the tube-trailer, the compressors, the chillers, and the banks. Compared to a single high-pressure bank system of 3000 L, the volume of the cascade high-pressure banks (bank1: 250 L and bank 2: 1850 L) was reduced by 30%, and the power consumption of the chiller for precooling was also decreased by 16%.

Keywords: light-duty vehicles, economic analysis, cascade system, hydrogen refueling station

Procedia PDF Downloads 97

Authors: Havish Nalapareddy, Mark V. Albert, Ranak Bansal, Avi Udash, Lin Lin

Abstract:

Students engage in many course projects during their degree programs. However, impactful projects often need a time frame longer than a single semester. Ideally, projects are documented and structured to be readily accessible to future students who may choose to continue the project, with features that emphasize the local community, university, or course structure. The Research and Project Portal (RAPP) is a place where students can post both their completed and ongoing projects with all the resources and tools used. This portal allows students to see what other students have done in the past, in the same university environment, related to their domain of interest. Computer science instructors or students selecting projects can use this portal to assign or choose an incomplete project. Additionally, this portal allows non-computer science faculty and industry collaborators to document their project ideas for students in courses to prototype directly, rather than directly soliciting the help of instructors in engaging students. RAPP serves as a platform linking students across classes and faculty both in and out of computer science courses on joint projects to encourage long-term project efforts across semesters or years.

Keywords: education, technology, research, academic portal

Procedia PDF Downloads 141

Authors: Xin Shi, Wei Tan, Guorui Zhu

Abstract:

The contraction-expansion array (CEA) microfluidic device is widely used for particle focusing and particle separation. Without the introduction of external fields, it can manipulate particles using hydrodynamic forces, including inertial lift forces and Dean drag forces. The focusing pattern of the particles in a CEA channel can be affected by the structural parameter, block ratio, and flow streamlines. Here, two typical focusing patterns with five different structural parameters were investigated, and the force mechanism was analyzed. We present nine CEA channels with different aspect ratios based on the process of changing the particle equilibrium positions. The results show that 10-15 μm particles have the potential to generate a side focusing line as the structural parameter (¬R𝓌) increases. For a determined channel structure and target particles, when the Reynolds number (Rₑ) exceeds the critical value, the focusing pattern will transform from a single pattern to a double pattern. The parameter α/R𝓌 can be used to calculate the critical Reynolds number for the focusing pattern transformation. The results can provide guidance for microchannel design and biomedical analysis.

Keywords: microfluidic, inertial focusing, particle separation, Dean flow

Procedia PDF Downloads 83

Authors: Yantao Li, Jun Zheng

Abstract:

Food poison caused by consumption of contaminated food, especially seafood, is one of most serious public health threats worldwide. Vibrio parahaemolyticus is emerging bacterial pathogen and the leading cause of human gastroenteritis associated with food poison, especially in the southern coastal region of China. To successfully cause disease in host, bacterial pathogens need to overcome the host-derived stresses encountered during infection. One of the toxic chemical species elaborated by the host is nitric oxide (NO). NO is generated by acidified nitrite in the stomach and by enzymes of the inducible NO synthase (iNOS) in the host cell, and is toxic to bacteria. Bacterial pathogens have evolved some mechanisms to battle with this toxic stress. Such mechanisms include genes to sense NO produced from immune system and activate others to detoxify NO toxicity, and genes to repair the damage caused by toxic reactive nitrogen species (RNS) generated during NO toxic stress. However, little is known about the NO resistance in V. parahaemolyticus. In this study, a transposon coupled with next generation sequencing (Tn-seq) technology will be utilized to identify genes for NO resistance in V. parahaemolyticus. Our strategy will include construction the saturating transposon insertion library, transposon library challenging with NO, next generation sequencing (NGS), bioinformatics analysis and verification of the identified genes in vitro and in vivo.

Keywords: vibrio parahaemolyticus, nitric oxide, tn-seq, virulence

Procedia PDF Downloads 268

Authors: Sedat Yayla, Azhin Abdullah

Abstract:

In the process of constructing hydroelectric power plants, the Pelton turbine, which is characterized by its simple manufacturing and construction, is performed in high head and low water flow. Parameters of the turbine have to be comprised in the designing process for obtaining hydraulic turbine with the highest efficiency during different operating conditions. The present investigation applied three-dimensional computational fluid dynamics (CFD). In addition, the bucket of Pelton turbine models with different splitter angle and inlet velocity values were examined for determining the force and visualizing the flow pattern on the bucket. The study utilized two diverse bucket models at various inlet velocities (20, 25, 30,35and 40m/s) and four different splitter angles (55, 75,90and 115 degree) for finding out the impacts of every single parameter on the effective force on the bucket. The acquired outcomes revealed that there is a linear relationship between force and inlet velocity on the bucket. Furthermore, the results also uncovered that the relationship between splitter angle and force on the bucket is linear until 90 degree.

Keywords: bucket design, computational fluid dynamics (CFD), free surface flow, two-phase flow, volume of fluid (VOF)

Procedia PDF Downloads 272

Authors: Yunwei Zhang, Na Li, Yuhong Niu

Abstract:

Bone tissue engineering scaffold was regarded as an important clinical technology of curing bony defect. The patent protection of bone tissue engineering scaffold had been paid more attention and strengthened all over the world. This study analyzed the future development trends of international technologies in the field of bone tissue engineering scaffold and its patent protection. This study used the methods of data classification and classification indexing to analyze 2718 patents retrieved in the patent database. Results showed that the patents coming from United States had a competitive advantage over other countiries in the field of bone tissue engineering scaffold. The number of patent applications by a single company in U.S. was a quarter of that of the world. However, the capability of R&D in China was obviously weaker than global level, patents mainly coming from universities and scientific research institutions. Moreover, it would be predicted that synthetic organic materials as new materials would be gradually replaced by composite materials. The patent technology protections of composite materials would be more strengthened in the future.

Keywords: bone tissue engineering, patent analysis, Scaffold material, patent protection

Procedia PDF Downloads 138

Authors: Guillaume Bélanger, Jean-Philippe Fontaine, Clémence Hauduc

Abstract:

There is an undeniable thirst from organic chemists and from the pharmaceutical industry to access complex alkaloids with short syntheses. While medicinal chemists are interested in the fascinating wide range of biological properties of alkaloids, synthetic chemists are rather interested in finding new routes to access these challenging natural products of often low availability from nature. To synthesize complex polycyclic cores of natural products, reaction cascades or sequences performed one-pot offer a neat advantage over classical methods for their rapid increase in molecular complexity in a single operation. In counterpart, reaction cascades need to be run on substrates bearing all the required functional groups necessary for the key cyclizations. Chemoselectivity is thus a major issue associated with such a strategy, in addition to diastereocontrol and regiocontrol for the overall transformation. In the pursuit of synthetic efficiency, our research group developed an innovative one-pot transformation of linear substrates into bi- and tricyclic adducts applied to the construction of Aspidospermatan-type alkaloids. The latter is a rich class of indole alkaloids bearing a unique bridged azatricyclic core. Despite many efforts toward the synthesis of members of this family, efficient and versatile synthetic routes are still coveted. Indeed, very short, non-racemic approaches are rather scarce: for example, in the cases of aspidospermidine and aspidospermine, syntheses are all fifteen steps and over. We envisaged a unified approach to access several members of the Aspidospermatan alkaloids family. The key sequence features a highly chemoselective formamide activation that triggers a Vilsmeier-Haack cyclization, followed by an azomethine ylide generation and intramolecular cycloaddition. Despite the high density and variety of functional groups on the substrates (electron-rich and electron-poor alkenes, nitrile, amide, ester, enol ether), the sequence generated three new carbon-carbon bonds and three rings in a single operation with good yield and high chemoselectivity. A detailed study of amide, nucleophile, and dipolarophile variations to finally get to the successful combination required for the key transformation will be presented. To complete the indoline fragment of the natural products, we developed an original approach. Indeed, all reported routes to Aspidospermatan alkaloids introduce the indoline or indole early in the synthesis. In our work, the indoline needs to be installed on the azatricyclic core after the key cyclization sequence. As a result, typical Fischer indolization is not suited since this reaction is known to fail on such substrates. We thus envisaged a unique photocatalyzed decarboxylative radical cyclization. The development of this reaction as well as the scope and limitations of the methodology, will also be presented. The original Vilsmeier-Haack and azomethine ylide cyclization sequence as well as the new photocatalyzed decarboxylative radical cyclization will undoubtedly open access to new routes toward polycyclic indole alkaloids and derivatives of pharmaceutical interest in general.

Keywords: Aspidospermatan alkaloids, azomethine ylide cycloaddition, decarboxylative radical cyclization, indole and indoline synthesis, one-pot sequential cyclizations, photocatalysis, Vilsmeier-Haack Cyclization

Procedia PDF Downloads 86

Authors: Ricardo Mestre

Abstract:

The soundscape stands out as an agglomeration of sounds available in the world, associated with different contexts and origins, being a theme studied by various areas of knowledge, seeking to guide their benefits and their consequences, contributing to the welfare of society and other ecosystems. Murray Schafer, the author who originally developed this concept, highlights the need for a greater recognition of sound reality, through the selection and differentiation of sounds, contributing to a tuning of the world and to the balance and well-being of humanity. According to some authors sound environment, produced and created in various ways, provides various sources of information, contributing to the orientation of the human being, alerting and manipulating him during his daily journey, like small notifications received on a cell phone or other device with these features. In this way, it becomes possible to give sound its due importance in relation to the processes of individual representation, in manners of social, professional and emotional life. Ensuring an individual representation means providing the human being with new tools for the long process of reflection by recognizing his environment, the sounds that represent him, and his perspective on his respective function in it. In order to provide more information about the importance of the sound environment inherent to the individual reality, one introduces the term sound instance, in order to refer to the whole sound field existing in the individual's life, which is divided into four distinct subfields, but essential to the process of individual representation, called sound matrix, sound cycles, sound traces and sound interference.

Keywords: sound instance, soundscape, sound art, perception, composition

Procedia PDF Downloads 151

Authors: Omolola Soji-Omoniwa, Babasoji Omoniwa

Abstract:

The hypolipidemic effect of leaf essential oil of Citrus sinensis in alloxan–induced diabetic rats was evaluated. Forty albino rats (150–200 g) were randomly selected into 4 groups of 10 rats each, representing Normal Control, Diabetic Control, Diabetic treated with 14.2 mg/kg body weight Metformin and Diabetic treated with 110 mg/kg body weight leaf essential oil of Citrus sinensis. Diabetes was induced in the animals by intraperitoneal administration of single dose alloxan monohydrate (150 mg/kg body weight). The leaf essential oil of Citrus sinensis was administered every other day to the Diabetic rats for a period of 15 days. The effects of leaf essential oil on High Density Lipoprotein (HDL), Low Density Lipoprotein (LDL), Trigylcerides and Cholesterol were evaluated. A significant reduction (p <0.05) in LDL, Triglycerides and cholesterol levels and a significant increase (p<0 .05) in HDL was observed. Leaf essential oil of Citrus sinensis possesses hypolipidemic properties.

Keywords: Citrus sinensis, Diabetes mellitus, hypolipidemic, leaf essential oil

Procedia PDF Downloads 452

Authors: Khalid Achaat

Abstract:

It is difficult to speak about freedom of the press in Algeria without first talking to fifty-seven journalists killed in the country between 1993 and 1997 and the five missing journalists. No serious investigation was conducted to find the culprits. When a State is not able to guarantee law, there is no justice and violations of the law become "systematic". How to claim the freedom of press in Algeria, when death becomes "banal"? In these circumstances, can we talk of rights of the Algerian press? It is impossible to understand the problems of the press in Algeria, focusing solely legal issues. Take into account technical, financial and political. Their respective roles varies depending on whether one focuses on the collection of information, the regime of the newspaper company or publication and dissemination. Can we say that the Algerian press is "the freest in the Arab world", while the latter reflects only partially the real problems facing the country? While any newspaper company is subject, de facto, to an authorization scheme, permanently subjected to the constant threat of withdrawal of the authorization, suspension, prohibition or closure without it has the right to a remedy? Can it be free when the majority of "media owners", head of the largest daily newspapers are derived from the single party in power since independence? Some of this release does not it serves the interests of the Algerian power?

Keywords: freedom, press, power, closure, suspension

Procedia PDF Downloads 353

Authors: Devina Jain

Abstract:

The choice between single-use drinking glasses and reusable glasses is of major concern to our lifestyles, and hence, the environment. This study is aimed at comparing three systems - a disposable paper cup, a disposable cup and a reusable stainless steel cup or glass - with respect to their effect on the environment to find out which one is more advantageous for reducing the impact on the environment. Life Cycle Assessment was conducted using modeling software, Umberto NXT Universal (Version 7.1). For the purpose of this study, the cradle to grave approach was considered. Results showed that cleaning is of a very strong influence on the environmental burden by these drinking systems, with a contribution of up to 90 to 100%. Thus, the burden is determined by the way in which the utensils are washed, and how much water is consumed. It maybe seems like a small, insignificant daily practice. In the short term, it would seem that paper and plastic cups are a better idea, since they are easy to acquire and do not need to be stored, but in the long run, we can say that steel cups will have less of an environmental impact. However, if the frequency of use and the number of glasses employed per use are of significance to decide the appropriateness of the usage, it is better to use disposable cups and glasses.

Keywords: disposable glass, life cycle assessment, paper, plastic, reusable glass, stainless steel

Procedia PDF Downloads 343

Authors: N. Rassoul-ibrahim, E. Siahmed, L. Tadrist

Abstract:

Water management plays a crucial role in the performance and durability of PEM fuel cells. Whereas the membrane must be hydrated enough, liquid droplets formed by water in excess can block the flow in the gas distribution channels and hinder the fuel cell performance. The main purpose of this work is to increase the understanding of liquid transport and mixing through mini- or micro-channels for various engineering or medical process applications including cool-ing of equipment according to the operations considered. For that purpose and as a first step, a technique was devel-oped to automatically detect and characterize two-phase flow patterns that may appear in such. The investigation, mainly experimental, was conducted on transparent channel with a 1mm x 1mm square cross section and a 0.3mm x 0.3 mm water injection normal to the gas channel. Three main flow patterns were identified liquid slug, bubble flow and annular flow. A flow map has been built accord-ing to the flow rate of both phases. As a sample the follow-ing figures show representative images of the flow struc-tures observed. An analysis and discussion of the flow pattern, in mini-channel, will be provided and compared to the case old micro-channel. . Keywords: Two phase flow, Clean Energy, Minichannels, Fuel Cells. Flow patterns, Maps.

Keywords: two phase flox, T-juncion, Micro and minichannels, clean energy, flow patterns, maps

Procedia PDF Downloads 80

Authors: Pushpendra S. Bharti

Abstract:

Process yield of electric discharge machining (EDM) is directly related to optimal combination(s) of process parameters. Optimization of process parameters of EDM is a multi-objective optimization problem owing to the contradictory behavior of performance measures. This paper employs Grey Relation Analysis (GRA) method as a multi-objective optimization technique for the optimal selection of process parameters combination. In GRA, multi-response optimization is converted into optimization of a single response grey relation grade which ultimately gives the optimal combination of process parameters. Experiments were carried out on die-sinking EDM by taking D2 steel as work piece and copper as electrode material. Taguchi's orthogonal array L36 was used for the design of experiments. On the experimental values, GRA was employed for the parametric optimization. A significant improvement has been observed and reported in the process yield by taking the parametric combination(s) obtained through GRA.

Keywords: electric discharge machining, grey relation analysis, material removal rate, optimization

Procedia PDF Downloads 413

Authors: Abdelghani Choucha, Lakhdar Chaib, Salem Arif

Abstract:

This paper treated the problem of power system stability with the aid of Static Synchronous Series Compensator (SSSC) installed in the transmission line of single machine infinite bus (SMIB) power system. A fractional order PID (FOPID) controller has been applied as a robust controller for optimal SSSC design to control the power system characteristics. Additionally, the SSSC based FOPID parameters are smoothly tuned using Invasive Weed Optimization algorithm (IWO). To verify the strength of the proposed controller, SSSC based FOPID controller is validated in a wide range of operating condition and compared with the conventional scheme SSSC-POD controller. The main purpose of the proposed process is greatly enhanced the dynamic states of the tested system. Simulation results clearly prove the superiority and performance of the proposed controller design.

Keywords: SSSC-FOPID, SSSC-POD, SMIB power system, invasive weed optimization algorithm

Procedia PDF Downloads 189

Authors: Nicole Nazario Bayon, Prathima Prabhu Tumkur, Nithin Krisshna Gunasekaran, Krishnan Prabhakaran, Joseph C. Hall, Govindarajan T. Ramesh

Abstract:

Titanium nitride (TiN) nanoparticles have sparked interest over the past decade due to their characteristics such as thermal stability, extreme hardness, low production cost, and similar optical properties to gold. In this study, TiN nanoparticles were synthesized via a thermal benzene route to obtain a black powder of nanoparticles. The final product was drop cast onto conductive carbon tape and sputter coated with gold/palladium at a thickness of 4 nm for characterization by field emission scanning electron microscopy (FE-SEM) with energy dispersive X-Ray spectroscopy (EDX) that revealed they were spherical. ImageJ software determined the average size of the TiN nanoparticles was 79 nm in diameter. EDX revealed the elements present in the sample and showed no impurities. Further characterization by X-ray diffraction (XRD) revealed characteristic peaks of cubic phase titanium nitride, and crystallite size was calculated to be 14 nm using the Debye-Scherrer method. Dynamic light scattering (DLS) analysis revealed the size and size distribution of the TiN nanoparticles, with average size being 154 nm. Zeta potential concluded the surface of the TiN nanoparticles is negatively charged. Biocompatibility studies using MTT(3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay showed TiN nanoparticles are not cytotoxic at low concentrations (2, 5, 10, 25, 50, 75 mcg/well), and cell viability began to decrease at a concentration of 100 mcg/well.

Keywords: biocompatibility, characterization, cytotoxicity, nanoparticles, synthesis, titanium nitride

Procedia PDF Downloads 187

Authors: Alex Elentukh

Abstract:

The paper is based on data collected from final exams administered during five years of teaching the graduate course in software engineering. The visualization instrument with four distinct personas has been used to improve the effectiveness of each class. The study offers a plethora of clues toward students' behavioral preferences. Diversity among students (professional background, physical proximity) is too significant to assume a single face of a learner. This is particularly true for a body of online graduate students in computer science. Conclusions of the study (each learner is unique, and each class is unique) are extrapolated to demystify the notion of an 'average software engineer.' An immediate direction for an educator is to ensure a course applies to a wide audience of very different individuals. On the other hand, a student should be clear about his/her abilities and preferences - to follow the most effective learning path.

Keywords: K.3.2 computer and information science education, learner profiling, adaptive learning, software engineering

Procedia PDF Downloads 107

Authors: A. Alyami, S. Christmas, K. Neeltje, G. Pollakis, B. Paxton, Z. Al-Bayati

Abstract:

The Human leukocyte antigen-G (HLA-G) molecule plays an important role in immunomodulation. To date, 16 untranslated regions (UTR) HLA-G haplotypes have been previously defined by sequenced SNPs in the coding region. From these, UTR-1, UTR-2, UTR-3, UTR-4, UTR-5, UTR-6 and UTR-7 are the most frequent 3’UTR haplotypes at the global level. UTR-1 is associated with higher levels of soluble HLA-G and HLA-G expression, whereas UTR-5 and UTR-7 are linked with low levels of soluble HLA-G and HLA-G expression. Human immunodeficiency virus type 1 (HIV-1) infection results in the progressive loss of immune function in infected individuals. The virus escape mechanism typically includes T lymphocytes and NK cell recognition and lyses by classical HLA-A and B down-regulation, which has been associated with non-classical HLA-G molecule up-regulation, respectively. We evaluated the haplotypes of the HLA-G 3′ untranslated region frequencies observed in three HIV-1 groups from the Netherlands and their susceptibility to develop infection. The three groups are made up of mainly men who have sex with men (MSM), injection drug users (IDU) and a high-risk-seronegative (HRSN) group. DNA samples were amplified with published primers prior sequencing. According to our results, the low expresser frequencies show higher in HRSN compared to other groups. This is indicating that 3’UTR polymorphisms may be identified as potential prognostic biomarkers to determine susceptibility to HIV.

Keywords: Human leukocyte antigen-G (HLA-G) , men who have sex with men (MSM), injection drug users (IDU), high-risk-seronegative (HRSN) group, high-untranslated region (UTR)

Procedia PDF Downloads 155

Authors: Fethi Soltani, Adel Almarashi, Idir Mechai

Abstract:

Tikhonov regularization and reproducing kernels are the most popular approaches to solve ill-posed problems in computational mathematics and applications. And the Fourier multiplier operators are an essential tool to extend some known linear transforms in Euclidean Fourier analysis, as: Weierstrass transform, Poisson integral, Hilbert transform, Riesz transforms, Bochner-Riesz mean operators, partial Fourier integral, Riesz potential, Bessel potential, etc. Using the theory of reproducing kernels, we construct a simple and efficient representations for some class of Fourier multiplier operators Tm on the Paley-Wiener space Hh. In addition, we give an error estimate formula for the approximation and obtain some convergence results as the parameters and the independent variables approaches zero. Furthermore, using numerical quadrature integration rules to compute single and multiple integrals, we give numerical examples and we write explicitly the extremal function and the corresponding Fourier multiplier operators.

Keywords: fourier multiplier operators, Gauss-Kronrod method of integration, Paley-Wiener space, Tikhonov regularization

Procedia PDF Downloads 323

Authors: Ashish Kumar Pathak, Ritika Sharma, Vishal Nath, Sudhir Pratap Singh, Rakesh Tuli

Abstract:

Litchi is a sub-tropical fruit crop with genotypes bearing delicious juicy fruits with variable seed size (bold to rudimentary size). Small seed size is a desirable trait in litchi, as it increases consumer acceptance and fruit processing. The biochemical activities in mid- stage ovules (e.g. 16, 20, 24 and 28 days after anthesis) determine the fate of seed and fruit development in litchi. Comprehensive ovule-specific transcriptome analysis was performed in two litchi genotypes with contrasting seed size to gain molecular insight on determinants of seed fates in litchi fruits. The transcriptomic data was de-novo assembled in 1,39,608 trinity transcripts, out of which 6,325 trinity transcripts were differentially expressed between the two contrasting genotypes. Differential transcriptional pattern was found among ovule development stages in contrasting litchi genotypes. The putative genes for salicylic acid, jasmonic acid and brassinosteroid pathway were down-regulated in ovules of small-seeded litchi. Embryogenesis, cell expansion, seed size and stress related trinity transcripts exhibited altered expression in small-seeded genotype. The putative regulators of seed maturation and seed storage were down-regulated in small-seed genotype.

Keywords: Litchi, seed, transcriptome, defence

Procedia PDF Downloads 248

Authors: Seid Yimer Abate, Ding-Chi Huang, Yu-Tai Tao

Abstract:

In this study, charge extraction characteristics at the perovskite/TiO2 interface in the conventional perovskite solar cell is studied by interface engineering. Self-assembled monolayers of phosphonic acids with different chain length and terminal functional group were used to modify mesoporous TiO2 surface to modulate the surface property and interfacial energy barrier to investigate their effect on charge extraction and transport from the perovskite to the mp-TiO2 and then the electrode. The chain length introduces a tunnelling distance and the end group modulate the energy level alignment at the mp-TiO2 and perovskite interface. The work function of these SAM-modified mp-TiO2 varied from −3.89 eV to −4.61 eV, with that of the pristine mp-TiO2 at −4.19 eV. A correlation of charge extraction and transport with respect to the modification was attempted. The study serves as a guide to engineer ETL interfaces with simple SAMs to improve the charge extraction, carrier balance and device long term stability. In this study, a maximum PCE of ~16.09% with insignificant hysteresis was obtained, which is 17% higher than the standard device.

Keywords: Energy level alignment, Interface engineering, Perovskite solar cells, Phosphonic acid monolayer, Tunnelling distance

Procedia PDF Downloads 141

Authors: Shijie Liu, Jehnming Lin

Abstract:

This study mainly discussed the mechanical properties of selective laser sintered 304L stainless steel powder specimen. According to a single layer specimen sintering, the microstructure and porosity were observed to find out the proper sintering parameters. A multi-layer sintering experiment was conducted. Based on the microstructure and the integration between layers, the suitable parameters were found out. Finally, the sintered specimens were examined by metallographical inspection, hardness test, tensile test, and surface morphology measurement. The structure of the molten powder coated with unmelted powder was found in metallographic test. The hardness of the sintered stainless steel powder is greater than the raw material. The tensile strength is less than the raw material, and it is corresponding to different scanning paths. The specimen will have different patterns of cracking. It was found that the helical scanning path specimen will have a warpage deformation at the edge of the specimen. The S-scan path specimen surface is relatively flat.

Keywords: laser sintering, sintering path, microstructure, mechanical properties

Procedia PDF Downloads 165

Authors: Bhavini Pandya

Abstract:

This paper considers Hη: T2 → T2 the Perturbed Cerbelli-Giona map. That is a family of 2-dimensional nonlinear area-preserving transformations on the torus T2=[0,1]×[0,1]= ℝ2/ ℤ2. A single parameter η varies between 0 and 1, taking the transformation from a hyperbolic toral automorphism to the “Cerbelli-Giona” map, a system known to exhibit multifractal properties. Here we study the multifractal properties of the family of maps. We apply a box-counting method by defining a grid of boxes Bi(δ), where i is the index and δ is the size of the boxes, to quantify the distribution of stable and unstable manifolds of the map. When the parameter is in the range 0.51< η <0.58 and 0.68< η <1 the map is ergodic; i.e., the unstable and stable manifolds eventually cover the whole torus, although not in a uniform distribution. For accurate numerical results we require correspondingly accurate construction of the stable and unstable manifolds. Here we use the piecewise linearity of the map to achieve this, by computing the endpoints of line segments which define the global stable and unstable manifolds. This allows the generalized fractal dimension Dq, and spectrum of dimensions f(α), to be computed with accuracy. Finally, the intersection of the unstable and stable manifold of the map will be investigated, and compared with the distribution of periodic points of the system.

Keywords: feed forward, gradient descent, neural network, integral equation

Procedia PDF Downloads 191