Search results for: electronic democracy

Authors: Maged Assem Soliman Mossallam

Abstract:

One of the main prospectives on the demand of space exploration is to reduce the costs and efforts for satellite design. Concerning this issue satellite down scaling attracts space scientists and engineers. Picosatellite is the smallest category of satellites. The overall mass is less than 1 kg and dimensions are 10x10x3 cm3. Thermal control target is to keep the Pico-satellite board temperature within the permissible limits of temperature. Thermal design is completely passive which relies mainly on the enhancement of the thermo-optical properties of aluminum using anodization. Transient analysis is given for two different orbits, ISS orbit and 600 km altitude orbit. Results show that board temperature lies within 3 oC to 22 oC using black anodization which is a permissible limit for the satellite internal electronic board.

Keywords: satellite thermal control, small satellites, thermooptical properties , transient orbit analysis

Procedia PDF Downloads 107

Authors: Abdusalam Gsiea, Ramadan Al-habashi, Mohamed Atumi, Khaled Atmimi

Abstract:

We present a theoretical investigation on the structural, electronic properties and vibrational mode of nitrogen impurities in ZnO. The atomic structures, formation and transition energies and vibrational modes of (NO3)i interstitial or NO4 substituting on an oxygen site ZnO were computed using ab initio total energy methods. Based on Local density functional theory, our calculations are in agreement with one interpretation of bound-excition photoluminescence for N-doped ZnO. First-principles calculations show that (NO3)i defects interstitial or NO4 substituting on an Oxygen site in ZnO are important suitable impurity for p-type doping in ZnO. However, many experimental efforts have not resulted in reproducible p-type material with N2 and N2O doping. by means of first-principle pseudo-potential calculation we find that the use of NO or NO2 with O gas might help the experimental research to resolve the challenge of achieving p-type ZnO.

Keywords: DFF, nitrogen, p-type, ZnO

Procedia PDF Downloads 459

Authors: M. Fakhim Lamrani, M. Ouchri, M. Belaiche, El Kenz, M. Loulidi, A. Benyoussef

Abstract:

Electronic and magnetic calculations based on density functional theory within the generalized gradient approximation for II-VI compound semiconductor TiO2 doped with single impurity Os and Mo; these compounds are a half metallic ferromagnet in their ground state with a total magnetic moment of 2 μB for both systems. Then, TiO2 doped with double impurities Os and Mo have been performed. As result, Ti1-2xOsxMoxO2 with x=0.065 is half-metallic antiferromagnets with 100% spin polarization of the conduction electrons crossing the Fermi level, without showing a net magnetization. Moreover, Ti14OsMoO32 compound is stable energetically than Ti1-xMoxO2 and Ti1-xOsxO2. The antiferromagnetic interaction in Ti1-2xOsxMoxO2 system is attributed to the double exchange mechanism, and the latter could also be the origin of their half metallic.

Keywords: diluted magnetic semiconductor, half-metallic antiferromagnetic, augmented spherical wave method

Procedia PDF Downloads 416

Authors: W. Ait Ahmed, M. Aggour, M. Naciri

Abstract:

Extracting energy from biomass is an important alternative to produce different types of energy (heat, electricity, or both) assuring low pollution and better efficiency. It is a new yet reliable approach to reduce green gas emission by extracting methane from industry effluents and use it to power machinery. We focused in our project on using paper and mill effluents, treated in a UASB reactor. The methane produced is used in the factory’s power supply. The aim of this work is to develop an electronic system using Arduino platform connected to a gas sensor, to measure and display the curve of daily methane production on processing. The sensor will send the gas values in ppm to the Arduino board so that the later sends the RS232 hardware protocol. The code developed with processing will transform the values into a curve and display it on the computer screen.

Keywords: biogas, Arduino, processing, code, methane, gas sensor, program

Procedia PDF Downloads 307

Authors: A. Fahim, Mutahira N. Naseem

Abstract:

SPAM is any unwanted electronic message or material in any form posted to many people. As the world is growing as global world, social networking sites play an important role in making world global providing people from different parts of the world a platform to meet and express their views. Among different social networking sites facebook become the leading one. With increase in usage different users start abusive use of facebook by posting or creating ways to post spam. This paper highlights the potential spam types nowadays facebook users faces. This paper also provide the reason how user become victim to spam attack. A methodology is proposed in the end discusses how to handle different types of spam.

Keywords: artificial neural networks, facebook spam, social networking sites, spam filter

Procedia PDF Downloads 369

Authors: Shabir Ahmad Sofi, Shubham Aggarwal, Sanyam Singhal, Roohie Naaz

Abstract:

Biometric recognition refers to an automatic recognition of individuals based on a feature vector(s) derived from their physiological and/or behavioral characteristic. Biometric recognition systems should provide a reliable personal recognition schemes to either confirm or determine the identity of an individual. These features are used to provide an authentication for computer based security systems. Applications of such a system include computer systems security, secure electronic banking, mobile phones, credit cards, secure access to buildings, health and social services. By using biometrics a person could be identified based on 'who she/he is' rather than 'what she/he has' (card, token, key) or 'what she/he knows' (password, PIN). In this paper, a brief overview of biometric methods, both unimodal and multimodal and their advantages and disadvantages, will be presented.

Keywords: biometric, DNA, fingerprint, ear, face, retina scan, gait, iris, voice recognition, unimodal biometric, multimodal biometric

Procedia PDF Downloads 749

Authors: Rajan Ghimire

Abstract:

One of the diseases caused by the coronavirus shook the whole world. This situation challenged the education system across the world and compelled educators to shift to an online mode of teaching. Many academic institutions that were persistent to keep their traditional pedagogical approach were also forced to change their teaching methods. This study aims to assess science education students' experiences and perceptions of this global issue, especially on the science teaching and learning process. The study is based on qualitative research and through in-depth interviews with respondents and data is analyzed. Online distance teaching and learning processes meet the requirements of students who cannot or prefer not to participate in conventional classroom settings. But there are some challenges for the students and teachers in the science teaching learning process. This study recommends some points to all stakeholders.

Keywords: electronic devices, internet, online and distance learning, science education, educational policy

Procedia PDF Downloads 46

Authors: Hussein Shaman

Abstract:

This study introduces an innovative design for an RF phase shifter that can maintain a consistent phase shift across a broad spectrum of frequencies. The proposed design integrates an adaptive control system into a reflective-type phase shifter, typically showing frequency-related variations. Adjusting the DC voltage according to the frequency ensures a more reliable phase shift across the frequency span of operation. In contrast, conventional frequency-dependent reflective-type phase shifters may exhibit significant fluctuations in phase shifts exceeding 60 degrees in the same bandwidth. The proposed phase shifter is configured to deliver a 90-degree operation with an expected deviation of around 15 degrees. The fabrication of the phase shifter and adaptive control circuit has been verified through experimentation, with the measured outcomes aligning with the simulation results.

Keywords: phase shifter, adaptive control, varactors, electronic circuits.

Procedia PDF Downloads 59

Authors: Rujia Chen, Akbar Ghobakhlou, Ajit Narayanan

Abstract:

This study investigates the task of identifying musical instruments in polyphonic compositions using Convolutional Neural Networks (CNNs) from spectrogram inputs, focusing on binary classification. The model showed promising results, with an accuracy of 97% on solo instrument recognition. When applied to polyphonic combinations of 1 to 10 instruments, the overall accuracy was 64%, reflecting the increasing challenge with larger ensembles. These findings contribute to the field of Music Information Retrieval (MIR) by highlighting the potential and limitations of current approaches in handling complex musical arrangements. Future work aims to include a broader range of musical sounds, including electronic and synthetic sounds, to improve the model's robustness and applicability in real-time MIR systems.

Keywords: binary classifier, CNN, spectrogram, instrument

Procedia PDF Downloads 67

Authors: Mohsen Khaledian, Razali Ismail, Mehdi Saeidmanesh, Mahdiar Hosseinghadiry

Abstract:

A semi-analytical model for impact ionization coefficient of graphene nanoribbon (GNR) is presented. The model is derived by calculating probability of electrons reaching ionization threshold energy Et and the distance traveled by electron gaining Et. In addition, ionization threshold energy is semi-analytically modeled for GNR. We justify our assumptions using analytic modeling and comparison with simulation results. Gaussian simulator together with analytical modeling is used in order to calculate ionization threshold energy and Kinetic Monte Carlo is employed to calculate ionization coefficient and verify the analytical results. Finally, the profile of ionization is presented using the proposed models and simulation and the results are compared with that of silicon.

Keywords: nanostructures, electronic transport, semiconductor modeling, systems engineering

Procedia PDF Downloads 469

Authors: Halimat M. Ajose-Adeogun, Zaynab A. Bello

Abstract:

Artificial Intelligence (AI) and Natural Language Processing (NLP) have transformed computer language comprehension, allowing computers to comprehend spoken and written language with human-like cognition. NLP, a multidisciplinary area that combines rule-based linguistics, machine learning, and deep learning, enables computers to analyze and comprehend human language. NLP applications in medicine range from tackling issues in electronic health records (EHR) and psychiatry to improving diagnostic precision in orthopedic surgery and optimizing clinical procedures with novel technologies like chatbots. The technology shows promise in a variety of medical sectors, including quicker access to medical records, faster decision-making for healthcare personnel, diagnosing dysplasia in Barrett's esophagus, boosting radiology report quality, and so on. However, successful adoption requires training for healthcare workers, fostering a deep understanding of NLP components, and highlighting the significance of validation before actual application. Despite prevailing challenges, continuous multidisciplinary research and collaboration are critical for overcoming restrictions and paving the way for the revolutionary integration of NLP into medical practice. This integration has the potential to improve patient care, research outcomes, and administrative efficiency. The research methodology includes using NLP techniques for Sentiment Analysis and Emotion Recognition, such as evaluating text or audio data to determine the sentiment and emotional nuances communicated by users, which is essential for designing a responsive and sympathetic chatbot. Furthermore, the project includes the adoption of a Personalized Intervention strategy, in which chatbots are designed to personalize responses by merging NLP algorithms with specific user profiles, treatment history, and emotional states. The synergy between NLP and personalized medicine principles is critical for tailoring chatbot interactions to each user's demands and conditions, hence increasing the efficacy of mental health care. A detailed survey corroborated this synergy, revealing a remarkable 20% increase in patient satisfaction levels and a 30% reduction in workloads for healthcare practitioners. The poll, which focused on health outcomes and was administered to both patients and healthcare professionals, highlights the improved efficiency and favorable influence on the broader healthcare ecosystem.

Keywords: natural language processing, artificial intelligence, healthcare communication, electronic health records, patient care

Procedia PDF Downloads 70

Authors: D. Majumdar, M. Baskey, S. K. Saha

Abstract:

Graphene has already been identified as a promising material for future carbon based electronics. To develop graphene technology, the fabrication of a high quality P-N junction is a great challenge. In the present work, we have described a simple and general technique to grow single crystalline polyaniline (PANI) films on graphene sheets using in situ polymerization via the oxidation-reduction of aniline monomer and graphene oxide, respectively, to fabricate a high quality P-N junction, which shows diode-like behavior with a remarkably low turn-on voltage (60 mV) and high rectification ratio (1880:1) up to a voltage of 0.2 Volt. The origin of these superior electronic properties is the preferential growth of a highly crystalline PANI film as well as lattice matching between the d-values [~2.48 Å] of graphene and {120} planes of PANI.

Keywords: epitaxial growth, PANI, reduced graphene oxide, rectification ratio

Procedia PDF Downloads 284

Authors: Ming Luo

Abstract:

In this real world, a manufacturer may produce more than one product. The products produced by the same manufacturer may share the same type of parts, similar design, and be produced in the same factory, i.e. some common causes. From the perspective of warranty management, the frequencies of those products’ warranty claims may have statistical dependence caused by the common causes. Warranty policy optimisation in the existing research, majorly, has not considered such dependence, which may increase bias in decision making. In the market, renewing warranty policies are provided to some unrepairable products and consumer electronic products. This paper optimises the renewing warranty policy collectively in a multi-product scenario with a consideration of the dependence among the warranty claims of the products produced by the same manufacturer. The existence of the optimal solution is proved. Numerical examples are used to validate the applicability of the proposed methods.

Keywords: mean-risk framework, modern portfolio theory, renewing warranty policy, warranty policy optimisation

Procedia PDF Downloads 296

Authors: Jon Gunnar Bernburg

Abstract:

The present study addresses a topic that is fundamental to social movement theory, namely, the contingent link between movement support and movement participation. Usually, only a small fraction of those who agree with the cause of a social movement is mobilized into participating in it (a pattern sometimes referred to as 'the collective action problem'). However, historical moments sometimes emerge when many supporters become mobilized to participate in the movement, greatly enhancing the chance of movement success. By studying a case in point, this paper addresses the limited work on how support and participation are related at such critical moments. Specifically, the paper examines the association between supporting and participating in a huge 'pro-democracy' protest in Iceland in April 2016, in the wake of the global Panama Papers scandal. Organized via social media by only a handful of activists, but supported by a majority of Icelanders, the protest attracted about a fourth of the urban population, leading to a snap election and government change. Surveying Iceland’s urban population, this paper tests hypotheses about the processes mobilizing supporters to participate in the protest. The findings reveal how variables derived from the theories of biographical availability (males vs. females, working class vs. professionals), critical mass (expectations, prior protest success), and social embeddedness (close ties with protesters) moderate the association between protest support and participation. The study helps to account for one of the largest protests in Iceland’s history while contributing to the theory about how historical contexts shape the behavior of movement supporters.

Keywords: Iceland, crisis, protest support vs. participation, theories of mass mobilization

Procedia PDF Downloads 230

Authors: K. Hołda, D. Śliwa, K. Daniec, A. Nawrat

Abstract:

This article was created as part of the developed master's thesis. It attempts to present a newly developed device, which will support the work of specialists dealing with broadly understood cybersecurity terms. The device is contrived to automate security tests. In addition, it simulates potential cyberattacks in the most realistic way possible, without causing permanent damage to the network, in order to maximize the quality of the subsequent corrections to the tested network systems. The proposed solution is a fully operational prototype created from commonly available electronic components and a single board computer. The focus of the following article is not only put on the hardware part of the device but also on the theoretical and applicatory way in which implemented cybersecurity tests operate and examples of their results.

Keywords: Raspberry Pi, ethernet, automated cybersecurity tests, ARP, DNS, backdoor, TCP, password sniffing

Procedia PDF Downloads 120

Authors: Tina Beyene

Abstract:

In this paper examines the state of grassroots feminist activism in the backdrop of state feminism in Ethiopia. Specifically, I examine the impact of the Charities and Societies Proclamation (aka CSO law), a 2009 law that banned so-called foreign NGOs—i.e., those receiving more than 10% of its operating budget from non-local sources— from working in the areas of human rights, democracy, governance, and gender equality. Viewed as government retribution for the NGO opposition to the government in the 2005 elections, the law aimed to halt the work groups such as the Ethiopian Women Lawyers Association (EWLA), who were defined as a “foreign” NGO. Based on interviews with prominent Ethiopian women’s rights leaders in Addis Ababa, Ethiopia, I assess how grassroots feminist organizing adapts to state suppression on the one hand, and the aggressive entry of the state into women’s rights work on the other hand. While the 2009 law has slowed down the work of women’s rights activism, displaced feminists view feminist advocacy as cyclical and the state as neither fully adversarial nor an ally but rather as an instable entity that at times provides political openings to push ambitious feminist agendas. Grassroots activists are regrouping and developing new political responses strategies such as coding rights issues to fit state mandate; dissembling rights work in permissible social provision language; rechanneling political work into informal spaces and unregistered social clubs; innovating new funding partnerships, and reassembling as privately held research and advocacy companies. my study reveals how grassroots feminist politics operates in the shadow of a hostile state and within the confines of local politics.

Keywords: grassroots feminism, ethiopian feminism, civil society and gender, state feminism

Procedia PDF Downloads 167

Authors: H. El-Kamchouchi, Heba Gaber, Fatma Ahmed, Dalia H. El-Kamchouchi

Abstract:

A digital signature is an electronic signature form used by an original signer to sign a specific document. When the original signer is not in his office or when he/she travels outside, he/she delegates his signing capability to a proxy signer and then the proxy signer generates a signing message on behalf of the original signer. The two parties must be able to authenticate one another and agree on a secret encryption key, in order to communicate securely over an unreliable public network. Authenticated key agreement protocols have an important role in building a secure communications network between the two parties. In this paper, we present a secure proxy signature scheme over an efficient and secure authenticated key agreement protocol based on factoring and discrete logarithm problem.

Keywords: discrete logarithm, factoring, proxy signature, key agreement

Procedia PDF Downloads 303

Authors: Anthony Vandarakis

Abstract:

Today’s International Service Learning practices require an update: modern technologies, fresh educational frameworks, and a new operating system to accountably prosper. This paper describes a model of International Service Learning (ISL), which combines current technological hardware, electronic platforms, and asynchronous communications that are grounded in inclusive pedagogy. This model builds on the work around collaborative field trip learning, extending the reach to international partnerships across continents. Mobile technology, 21^st century skills and summit-basecamp modeling intersect to support novel forms of learning that tread lightly on fragile natural ecosystems, affirm local reciprocal partnership in projects, and protect traveling participants from common yet avoidable cultural pitfalls.

Keywords: International Service Learning, ISL, field experiences, mobile technology, out there in here, summit basecamp pedagogy

Procedia PDF Downloads 169

Authors: Walter Sebron, Hans Tschürtz, Peter Krebs

Abstract:

The choice of applicable analysis methods in safety or systems engineering depends on the depth of knowledge about a system, and on the respective lifecycle phase. However, the analysis method chain still shows gaps as it should support system analysis during the lifecycle of a system from a rough concept in pre-project phase until end-of-life. This paper’s goal is to discuss an analysis method, the VISSE Shell Model Analysis (VISMA) method, which aims at closing the gap in the early system lifecycle phases, like the conceptual or pre-project phase, or the project start phase. It was originally developed to aid in the definition of the system boundary of electronic system parts, like e.g. a control unit for a pump motor. Furthermore, it can be also applied to non-electronic system parts. The VISMA method is a graphical sketch-like method that stratifies a system and its parts in inner and outer shells, like the layers of an onion. It analyses a system in a two-step approach, from the innermost to the outermost components followed by the reverse direction. To ensure a complete view of a system and its environment, the VISMA should be performed by (multifunctional) development teams. To introduce the method, a set of rules and guidelines has been defined in order to enable a proper shell build-up. In the first step, the innermost system, named system under consideration (SUC), is selected, which is the focus of the subsequent analysis. Then, its directly adjacent components, responsible for providing input to and receiving output from the SUC, are identified. These components are the content of the first shell around the SUC. Next, the input and output components to the components in the first shell are identified and form the second shell around the first one. Continuing this way, shell by shell is added with its respective parts until the border of the complete system (external border) is reached. Last, two external shells are added to complete the system view, the environment and the use case shell. This system view is also stored for future use. In the second step, the shells are examined in the reverse direction (outside to inside) in order to remove superfluous components or subsystems. Input chains to the SUC, as well as output chains from the SUC are described graphically via arrows, to highlight functional chains through the system. As a result, this method offers a clear and graphical description and overview of a system, its main parts and environment; however, the focus still remains on a specific SUC. It helps to identify the interfaces and interfacing components of the SUC, as well as important external interfaces of the overall system. It supports the identification of the first internal and external hazard causes and causal chains. Additionally, the method promotes a holistic picture and cross-functional understanding of a system, its contributing parts, internal relationships and possible dangers within a multidisciplinary development team.

Keywords: analysis methods, functional safety, hazard identification, system and safety engineering, system boundary definition, system safety

Procedia PDF Downloads 223

Authors: M. Taibeche, L. Guerbous, M. Kechouane, R. Nedjar, T. Zergoug

Abstract:

It is known that Y2O3 Material is the most important among the sesquioxides within the general class of refractory ceramics. Indeed, this compound has many applications such as sintering optical windows, components for rare-earth doped lasers as well as inorganic scintillators in the detection scintillation. In particular Eu2+ and Ce3+ are favored dopants in many the scintillators due to its allowed optical 5d-4f transition. In this work, we present new results concerning structural and electronic properties of Ce-doped Y2O3, investigated by density functional theory (DFT), using the Heyd–Scuseria–Ernzerhof (HSE) hybrid functional and DFT+U two approaches. When, we compared the results from the two methods we obtain a good agreement available experimental data. Furthermore, the effect of cerium on the material has also been studied and discussed in the same framework.

Keywords: DFT, vienne ab initio simulation packages, scintillators, Heyd–Scuseria–Ernzerhof (HSE) hybrid functional

Procedia PDF Downloads 510

Authors: Miraç Savaş Turhan, Ali Danişman

Abstract:

Recently scholars of new institutional theory have used institutional logics perspective to explain the contradictory practices in modern western societies. Accordingly, distinct institutional logics are embedded in central institutions such as the market, state, democracy, family, and religion. They guide individual and organizational actors and constraint their behaviors in a particular organizational field. Through this perspective, actors are assumed to have a situated, embedded, boundedly intentional, and adaptive role against the structure in social, cultural and political context. On the other hand, over a decade, there is an emerging attempt focusing on the role of actors on creating, maintaining, and changing the institutions. Such attempts brought out the concept of institutional entrepreneurs to explain the role of individual actors in relation to institutions. Institutional entrepreneurs are individuals, groups of individuals, organizations or groups of organizations that are able to initiate some actions to build, maintain or change institutions. While recent studies on institutional logics perspective have attempted to explain roles of entrepreneurial actors who have resources and skills, little is known about the effects of multiple institutional logics on the ability of institutional entrepreneurs. In this study, we aim to find out that how multiple institutional logics affect the ability of institutional entrepreneurs during the process of institutional change. We examine this issue in the Turkish Education Field. While institutional logics were identified based on the previous studies in the education field, the actions taken by Turkish National Education Ministry from 2003 to 2013 was examined through content analysis The early results indicate that there are remarkable shift and contradictions in the ability of institutional entrepreneur in taking actions to change the field in relationship to balance of power shift among the carriers of institutional logics.

Keywords: institutional theory, institutional logics, institutional entrepreneurs, Turkish national education

Procedia PDF Downloads 348

Authors: Mani Gupta

Abstract:

This study deals with question: i) Whether ICT plays a positive role in improvement of efficiency of LIPs in terms of providing efficient services to the Users in LICs? and ii) Role of finance in terms of required technological logistics and infrastructure for usage of ICT based services to comfort in accessing databases by Users in LICs. This is based on primary data which are collected from various libraries and Information Centers of NCR Delhi. The survey conducted during December 15 and 31, 2010 on 496 respondents across 96 libraries and information centers in NCR Delhi through electronic data collection method. There is positive and emphatic relationship between ICT and its effect on improving the level of efficient services providing by LIPs in LICs in NCR Delhi. This is divided into 6 sub-headings and finally the outcomes.

Keywords: modern globalization, linear correlation, efficient service, internet revolution, logistics

Procedia PDF Downloads 354

Authors: Hilal Köse, Şeyma Dombaycıoğlu, Ali Osman Aydın, Hatem Akbulut

Abstract:

Rechargeable lithium-ion batteries (LIBs) have become promising power sources for a wide range of applications, such as mobile communication devices, portable electronic devices and electrical/hybrid vehicles due to their long cycle life, high voltage and high energy density. Graphite, as anode material, has been widely used owing to its extraordinary electronic transport properties, large surface area, and high electrocatalytic activities although its limited specific capacity (372 mAh g-1) cannot fulfil the increasing demand for lithium-ion batteries with higher energy density. To settle this problem, many studies have been taken into consideration to investigate new electrode materials and metal oxide/graphene composites are selected as a kind of promising material for lithium ion batteries as their specific capacities are much higher than graphene. Among them, SnO₂, an n-type and wide band gap semiconductor, has attracted much attention as an anode material for the new-generation lithium-ion batteries with its high theoretical capacity (790 mAh g-1). However, it suffers from large volume changes and agglomeration associated with the Li-ion insertion and extraction processes, which brings about failure and loss of electrical contact of the anode. In addition, there is also a huge irreversible capacity during the first cycle due to the formation of amorphous Li₂O matrix. To obtain high capacity anode materials, we studied on the synthesis and characterization of SnO₂-Graphene nanocomposites and investigated the capacity of this free-standing anode material in this work. For this aim, firstly, graphite oxide was obtained from graphite powder using the method described by Hummers method. To prepare the nanocomposites as free-standing anode, graphite oxide particles were ultrasonicated in distilled water with SnO2 nanoparticles (1:1, w/w). After vacuum filtration, the GO-SnO₂ paper was peeled off from the PVDF membrane to obtain a flexible, free-standing GO paper. Then, GO structure was reduced in hydrazine solution. Produced SnO2- graphene nanocomposites were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectrometer (EDS), and X-ray diffraction (XRD) analyses. CR2016 cells were assembled in a glove box (MBraun-Labstar). The cells were charged and discharged at 25°C between fixed voltage limits (2.5 V to 0.2 V) at a constant current density on a BST8-MA MTI model battery tester with 0.2C charge-discharge rate. Cyclic voltammetry (CV) was performed at the scan rate of 0.1 mVs-1 and electrochemical impedance spectroscopy (EIS) measurements were carried out using Gamry Instrument applying a sine wave of 10 mV amplitude over a frequency range of 1000 kHz-0.01 Hz.

Keywords: SnO₂-graphene, nanocomposite, anode, Li-ion battery

Procedia PDF Downloads 225

Authors: Hadi Kafil, Ali Ecder

Abstract:

Heat transfer by natural convection in two-dimensional and three-dimensional axisymmetric enclosure fitted with partially heated vertical walls is investigated numerically. The range of Rayleigh number is varied from 10³ until convective flow becomes unstable. This research focuses on multiplicity and transition phenomena in natural convection and is based on a parametric analysis to study the onset of bifurcations. It is found that, even at low Rayleigh numbers, the flow undergoes a series of turning-point bifurcations which increase the rate of natural convention. On the other hand, by partially heating or cooling the walls, more effective results can be achieved for both heating and cooling applications, such as cooling of electronic devices and heating processes in solidification and crystal growth.

Keywords: natural convection, partial heated, onset of bifurcation, Rayleigh number

Procedia PDF Downloads 365

Authors: Amin Amini

Abstract:

A Kinect sensor has been utilized as a cheap and accurate alternative to 3D laser scanners and electronic distance measurement (EDM) systems. This research presents an inexpensive and easy-to-setup system that utilizes the Microsoft Kinect v2 sensor as a surveying and measurement tool and investigates the possibility of using such a device as a replacement for conventional theodolite systems. The system was tested in an indoor environment where its accuracy in distance and angle measurements was tested using virtual markers in a 3D Cartesian environment. The system has shown an average accuracy of 97.94 % in measuring distances and 99.11 % and 98.84 % accuracy for area and perimeter, respectively, within the Kinect’s surveying range of 1.5 to 6 meters. The research also tested the system competency for relative angle determination between two objects.

Keywords: kinect v2, 3D measurement, depth map, ToF

Procedia PDF Downloads 63

Authors: Gautier Girard, Marion Martiny, Sebastien Mercier, Mohamad Jrad, Mohamed-Slim Bahi, Laurent Bodin, Francois Lechleiter, David Nevo, Sophie Dareys

Abstract:

Reliability of electronic devices has always been of highest interest for Aero-MIL and space applications. In any electronic device, Printed Circuit Board (PCB), providing interconnection between components, is a key for reliability. During the last decades, PCB technologies evolved to sustain and/or fulfill increased original equipment manufacturers requirements and specifications, higher densities and better performances, faster time to market and longer lifetime, newer material and mixed buildups. From the very beginning of the PCB industry up to recently, qualification, experiments and trials, and errors were the most popular methods to assess system (PCB) reliability. Nowadays OEM, PCB manufacturers and scientists are working together in a close relationship in order to develop predictive models for PCB reliability and lifetime. To achieve that goal, it is fundamental to characterize precisely base materials (laminates, electrolytic copper, …), in order to understand failure mechanisms and simulate PCB aging under environmental constraints by means of finite element method for example. The laminates are woven composites and have thus an orthotropic behaviour. The in-plane properties can be measured by combining classical uniaxial testing and digital image correlation. Nevertheless, the out-of-plane properties cannot be evaluated due to the thickness of the laminate (a few hundred of microns). It has to be noted that the knowledge of the out-of-plane properties is fundamental to investigate the lifetime of high density printed circuit boards. A homogenization method combining analytical and numerical approaches has been developed in order to obtain the complete elastic orthotropic behaviour of a woven composite from its precise 3D internal structure and its experimentally measured in-plane elastic properties. Since the mechanical properties of the resin surrounding the fibres are unknown, an inverse method is proposed to estimate it. The methodology has been applied to one laminate used in hyperfrequency spatial applications in order to get its elastic orthotropic behaviour at different temperatures in the range [-55°C; +125°C]. Next; numerical simulations of a plated through hole in a double sided PCB are performed. Results show the major importance of the out-of-plane properties and the temperature dependency of these properties on the lifetime of a printed circuit board. Acknowledgements—The support of the French ANR agency through the Labcom program ANR-14-LAB7-0003-01, support of CNES, Thales Alenia Space and Cimulec is acknowledged.

Keywords: homogenization, orthotropic behaviour, printed circuit board, woven composites

Procedia PDF Downloads 196

Authors: Djemai Bara, Mohamed Faouzi Mahboub, Djamila Bennaceur-Doumaz

Abstract:

In this work, the role of the preformed plasma created on the front face of a target, irradiated by a high intensity short pulse laser, in the framework of ion acceleration process, modeled by Target Normal Sheath Acceleration (TNSA) mechanism, is studied. This plasma is composed of cold ions governed by fluid equations and non-thermal & trapped with densities represented by a "Cairns-Gurevich" equation. The self-similar solution of the equations shows that electronic trapping and the presence of non-thermal electrons in the pre-plasma are both responsible in ion acceleration as long as the proportion of energetic electrons is not too high. In the case where the majority of electrons are energetic, the electrons are accelerated directly by the ponderomotive force of the laser without the intermediate of an accelerating plasma wave.

Keywords: Cairns-Gurevich Equation, ion acceleration, plasma expansion, pre-plasma

Procedia PDF Downloads 125

Authors: G. Sivakumar, T. Pratyusha, D. Gupta, W. Shen

Abstract:

To get ohmic contact between the cathode and organic semiconductor, transport layers are introduced between the active layer and the electrodes. Generally zinc oxide or titanium dioxide are used as electron transport layer. When electron transport layer is doped with lithium, the resultant film exhibited superior electronic properties, which enables faster electron transport. Doping is accomplished by heat treatment of films with Lithium salts. Li-doped films. We fabricated organic solar cell using PTB7(poly(3-hexylthiopene-2,5- diyl):PCBM(phenyl-C61-butyric acid methyl ester) and found that the solar cells prepared using Li doped films had better performance in terms of efficiency when compared to the undoped transport layers.

Keywords: electron transport layer, higher efficiency, lithium doping, ohmic contact

Procedia PDF Downloads 498

Authors: Zoaib Mirza

Abstract:

Half of the Muslim countries in the world have declared Islam the state religion in their constitutions. Yet, none of these countries have implemented authentic Islamic laws in line with the Quran (Holy Book), practices of Prophet Mohammad (P.B.U.H) called the Sunnah, and his four successors known as the Rightly Guided - Khalifa. Since their independence, these countries have adopted different government systems like Democracy, Dictatorship, Republic, Communism, and Monarchy. Instead of benefiting the people, these government systems have put these countries into political, social, and economic crises. These Islamic countries do not have equal representation and membership in worldwide political forums. Western countries lead these forums. Therefore, it is now imperative for the Muslim leaders of all these countries to collaborate, reset, and implement the original Islamic form of government, which led to the prosperity and success of people, including non-Muslims, 1400 years ago. They should unite as one nation under Khalifat, which means establishing the authority of Allah (SWT) and following the divine commandments related to the social, political, and economic systems. As they have declared Islam in their constitution, they should work together to apply the divine framework of the governance revealed by Allah (SWT) and implemented by Prophet Mohammad (P.B.U.H) and his four successors called Khalifas. This paper provides an overview of the downfall and the end of the Khalifat system by 1924, the ways in which the West caused political, social, and economic crises in the Muslim countries, and finally, a summary of the social, political, and economic systems implemented by the Prophet Mohammad (P.B.U.H) and his successors, Khalifas, called the Rightly Guided – Hazrat Abu Bakr (RA), Hazrat Omar (RA), Hazrat Usman (RA), and Hazrat Ali (RA).

Keywords: khalifat, khilafat-e-Rashida, the rightly guided, colonization, capitalism, neocolonization, government systems

Procedia PDF Downloads 113

Authors: Kazeem Oluwakemi Oseni, Kate Dingley

Abstract:

E-Service has moved from the usual manual and traditional way of rendering services to electronic service provision for the public and there are several reasons for implementing these services, Airline ticketing have gone from its manual traditional way to an intelligent web-driven service of purchasing. Many companies have seen their profits doubled through the use of online services in their operation and a typical example is Hewlett Packard (HP) which is rapidly transforming their after sales business into a profit generating e-service business unit. This paper will examine the various challenges confronting e-Service adoption and implementation in Nigeria and also analyse lessons learnt from e-Service adoption and implementation in Asia to see how it could be useful in Nigeria which is a lower middle income country. Based on the analysis of the online survey data. It has been identified that the public in Nigeria are much aware of e-Services but successful adoption and implementation have been the problems faced.

Keywords: e-government service, adoption, implementation, Nigeria, Asia

Procedia PDF Downloads 449