Search results for: cutting edge technology
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8628

Search results for: cutting edge technology

5478 Classifying Students for E-Learning in Information Technology Course Using ANN

Authors: Sirilak Areerachakul, Nat Ployong, Supayothin Na Songkla

Abstract:

This research’s objective is to select the model with most accurate value by using Neural Network Technique as a way to filter potential students who enroll in IT course by electronic learning at Suan Suanadha Rajabhat University. It is designed to help students selecting the appropriate courses by themselves. The result showed that the most accurate model was 100 Folds Cross-validation which had 73.58% points of accuracy.

Keywords: artificial neural network, classification, students, e-learning

Procedia PDF Downloads 411
5477 The Challenges of Cloud Computing Adoption in Nigeria

Authors: Chapman Eze Nnadozie

Abstract:

Cloud computing, a technology that is made possible through virtualization within networks represents a shift from the traditional ownership of infrastructure and other resources by distinct organization to a more scalable pattern in which computer resources are rented online to organizations on either as a pay-as-you-use basis or by subscription. In other words, cloud computing entails the renting of computing resources (such as storage space, memory, servers, applications, networks, etc.) by a third party to its clients on a pay-as-go basis. It is a new innovative technology that is globally embraced because of its renowned benefits, profound of which is its cost effectiveness on the part of organizations engaged with its services. In Nigeria, the services are provided either directly to companies mostly by the key IT players such as Microsoft, IBM, and Google; or in partnership with some other players such as Infoware, Descasio, and Sunnet. This action enables organizations to rent IT resources on a pay-as-you-go basis thereby salvaging them from wastages accruable on acquisition and maintenance of IT resources such as ownership of a separate data centre. This paper intends to appraise the challenges of cloud computing adoption in Nigeria, bearing in mind the country’s peculiarities’ in terms of infrastructural development. The methodologies used in this paper include the use of research questionnaires, formulated hypothesis, and the testing of the formulated hypothesis. The major findings of this paper include the fact that there are some addressable challenges to the adoption of cloud computing in Nigeria. Furthermore, the country will gain significantly if the challenges especially in the area of infrastructural development are well addressed. This is because the research established the fact that there are significant gains derivable by the adoption of cloud computing by organizations in Nigeria. However, these challenges can be overturned by concerted efforts in the part of government and other stakeholders.

Keywords: cloud computing, data centre, infrastructure, it resources, virtualization

Procedia PDF Downloads 336
5476 Breakthrough Innovation Thinking Technology of a Conglomerate for Next Generation Plan

Authors: Dongkyu Lee, Doan-Quoc Hoan, Soomi Shin

Abstract:

The purpose of this study is to suggest the Value Innovation type Breakthrough Innovation which is a Big Thinking Process that realizes a creative idea for the next generation innovation Master Plan of a company. The BI based on the PVI methodology is believed to contribute to the launching of a new business, the acquisition of new markets, and the development of an innovative management process.

Keywords: value, innovation, breakthrough innovation, Korean firm

Procedia PDF Downloads 579
5475 Next Generation UK Storm Surge Model for the Insurance Market: The London Case

Authors: Iacopo Carnacina, Mohammad Keshtpoor, Richard Yablonsky

Abstract:

Non-structural protection measures against flooding are becoming increasingly popular flood risk mitigation strategies. In particular, coastal flood insurance impacts not only private citizens but also insurance and reinsurance companies, who may require it to retain solvency and better understand the risks they face from a catastrophic coastal flood event. In this context, a framework is presented here to assess the risk for coastal flooding across the UK. The area has a long history of catastrophic flood events, including the Great Flood of 1953 and the 2013 Cyclone Xaver storm, both of which led to significant loss of life and property. The current framework will leverage a technology based on a hydrodynamic model (Delft3D Flexible Mesh). This flexible mesh technology, coupled with a calibration technique, allows for better utilisation of computational resources, leading to higher resolution and more detailed results. The generation of a stochastic set of extra tropical cyclone (ETC) events supports the evaluation of the financial losses for the whole area, also accounting for correlations between different locations in different scenarios. Finally, the solution shows a detailed analysis for the Thames River, leveraging the information available on flood barriers and levees. Two realistic disaster scenarios for the Greater London area are simulated: In the first scenario, the storm surge intensity is not high enough to fail London’s flood defences, but in the second scenario, London’s flood defences fail, highlighting the potential losses from a catastrophic coastal flood event.

Keywords: storm surge, stochastic model, levee failure, Thames River

Procedia PDF Downloads 224
5474 Digital Transformation and Environmental Disclosure in Industrial Firms: The Moderating Role of the Top Management Team

Authors: Yongxin Chen, Min Zhang

Abstract:

As industrial enterprises are the primary source of national pollution, environmental information disclosure is a crucial way to demonstrate to stakeholders the work they have done in fulfilling their environmental responsibilities and accepting social supervision. In the era of the digital economy, many companies, actively embracing the opportunities that come with digital transformation, have begun to apply digital technology to information collection and disclosure within the enterprise. However, less is known about the relationship between digital transformation and environmental disclosure. This study investigates how enterprise digital transformation affects environmental disclosure in 643 Chinese industrial companies, according to information processing theory. What is intriguing is that the depth (size) and breadth (diversity) of environmental disclosure linearly increase with the rise in the collection, processing, and analytical capabilities in the digital transformation process. However, the volume of data will grow exponentially, leading to a marginal increase in the economic and environmental costs of utilizing, storing, and managing data. In our empirical findings, linearly increasing benefits and marginal costs create a unique inverted U-shaped relationship between the degree of digital transformation and environmental disclosure in the Chinese industrial sector. Besides, based on the upper echelons theory, we also propose that the top management team with high stability and managerial capabilities will invest more effort and expense into improving environmental disclosure quality, lowering the carbon footprint caused by digital technology, maintaining data security etc. In both these contexts, the increasing marginal cost curves would become steeper, weakening the inverted U-shaped slope between DT and ED.

Keywords: digital transformation, environmental disclosure, the top management team, information processing theory, upper echelon theory

Procedia PDF Downloads 118
5473 Technology Changing Senior Care

Authors: John Kosmeh

Abstract:

Introduction – For years, senior health care and skilled nursing facilities have been plagued with the dilemma of not having the necessary tools and equipment to adequately care for senior residents in their communities. This has led to high transport rates to emergency departments and high 30-day readmission rates, costing billions of unnecessary dollars each year, as well as quality assurance issues. Our Senior care telemedicine program is designed to solve this issue. Methods – We conducted a 1-year pilot program using our technology coupled with our 24/7 telemedicine program with skilled nursing facilities in different parts of the United States. We then compared transports rates and 30-day readmission rates to previous years before the use of our program, as well as transport rates of other communities of similar size not using our program. This data was able to give us a clear and concise look at the success rate of reducing unnecessary transport and readmissions as well as cost savings. Results – A 94% reduction nationally of unnecessary out-of-facility transports, and to date, complete elimination of 30-day readmissions. Our virtual platform allowed us to instruct facility staff on the utilization of our tools and system as well as deliver treatment by our ER-trained providers. Delay waiting for PCP callbacks was eliminated. We were able to obtain lung, heart, and abdominal ultrasound imaging, 12 lead EKG, blood labs, auscultate lung and heart sounds, and collect other diagnostic tests at the bedside within minutes, providing immediate care and allowing us to treat residents within the SNF. Are virtual capabilities allowed for loved ones, family members, and others who had medical power of attorney to virtually connect with us at the time of visit, to speak directly with the medical provider, providing increased confidence in the decision to treat the resident in-house. The decline in transports and readmissions will greatly reduce governmental cost burdens, as well as fines imposed on SNF for high 30-day readmissions, reduce the cost of Medicare A readmissions, and significantly impact the number of patients visiting overcrowded ERs. Discussion – By utilizing our program, SNF can effectively reduce the number of unnecessary transports of residents, as well as create significant savings from loss of day rates, transportation costs, and high CMS fines. The cost saving is in the thousands monthly, but more importantly, these facilities can create a higher quality of life and medical care for residents by providing definitive care instantly with ER-trained personnel.

Keywords: senior care, long term care, telemedicine, technology, senior care communities

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5472 Automated Parking System

Authors: N. Arunraj, C. P. V. Paul, D. M. D. Jayawardena, W. N. D. Fernando

Abstract:

Traffic congestion with increased numbers of vehicles is already a serious issue for many countries. The absence of sufficient parking spaces adds to the issue. Motorists are forced to wait in long queues to park their vehicles. This adds to the inconvenience faced by a motorist, kept waiting for a slot allocation, manually done along with the parking payment calculation. In Sri Lanka, nowadays, parking systems use barcode technology to identify the vehicles at both the entrance and the exit points. Customer management is handled by the use of man power. A parking space is, generally permanently sub divided according to the vehicle type. Here, again, is an issue. Parking spaces are not utilized to the maximum. The current arrangement leaves room for unutilized parking spaces. Accordingly, there is a need to manage the parking space dynamically. As a vehicle enters the parking area, available space has to be assigned for the vehicle according to the vehicle type. The system, Automated Parking System (APS), provides an automated solution using RFID Technology to identify the vehicles. Simultaneously, an algorithm manages the space allocation dynamically. With this system, there is no permanent parking slot allocation for a vehicle type. A desktop application manages the customer. A Web application is used to manage the external users with their reservations. The system also has an android application to view the nearest parking area from the current location. APS is built using java and php. It uses LED panels to guide the user inside the parking area to find the allocated parking slot accurately. The system ensures efficient performance, saving precious time for a customer. Compared with the current parking systems, APS interacts with users and increases customer satisfaction as well.

Keywords: RFID, android, web based system, barcode, algorithm, LED panels

Procedia PDF Downloads 588
5471 Involvement of Stakeholders in the R&D and Innovation Process in Developing Country Context: An Analysis of the Nigeria Innovation System

Authors: B. O. Oyedoyin, M. O. Ilori, T. O. Oyebisi, B. A. Oluwale, O. O. Jegede

Abstract:

The study was designed to evaluate the business development and transfer of technologies to small manufacturing companies by research institutes in South Western Nigeria. The study covered all the industrial research institutions with headquarters in South Western Nigeria. The study showed that the involvement of scientists in innovation process was rated highest in the idea generation (4.14) and idea screening (4.29) phases; high in R&D (3.86) and fairly high in pilot plant development (2.71) and commercialization (2.43) phase. Their involvement was rated low in business analysis and development (2.14), and test marketing (2.29) phase. The involvement of engineers was rated highest in idea generation (3.28), fairly high in R&D (2.71), pilot plant development (2.57), and idea screening (2.40) phases. However, their involvement was rated low in business analysis and development (2.0), test marketing (2.0), and commercialization (1.28) phases. The involvement of technology marketers in innovation process was generally rated fairly high in R&D (2.7) and business analysis and development (2.6), and low in all the other phases of innovation. However, their involvement at IAR&T, FIIRO, and NIOMR in all the phases was rated very high (3.0-5.0). The involvement of entrepreneurs was generally rated from fairly high to low (2.7-2.3) in all the phases of innovation. The involvement of financial institutions in all the phases of innovation was generally rated low (1.28-1.71). In conclusion, the study showed that the involvement of stakeholders like entrepreneurs and financial institutions in technology packaging for commercialization is very low.

Keywords: research institutes, national innovation system, Nigeria, entrepreneurs, financial institution

Procedia PDF Downloads 414
5470 Designing Agricultural Irrigation Systems Using Drone Technology and Geospatial Analysis

Authors: Yongqin Zhang, John Lett

Abstract:

Geospatial technologies have been increasingly used in agriculture for various applications and purposes in recent years. Unmanned aerial vehicles (drones) fit the needs of farmers in farming operations, from field spraying to grow cycles and crop health. In this research, we conducted a practical research project that used drone technology to design and map optimal locations and layouts of irrigation systems for agriculture farms. We flew a DJI Mavic 2 Pro drone to acquire aerial remote sensing images over two agriculture fields in Forest, Mississippi, in 2022. Flight plans were first designed to capture multiple high-resolution images via a 20-megapixel RGB camera mounted on the drone over the agriculture fields. The Drone Deploy web application was then utilized to develop flight plans and subsequent image processing and measurements. The images were orthorectified and processed to estimate the area of the area and measure the locations of the water line and sprinkle heads. Field measurements were conducted to measure the ground targets and validate the aerial measurements. Geospatial analysis and photogrammetric measurements were performed for the study area to determine optimal layout and quantitative estimates for irrigation systems. We created maps and tabular estimates to demonstrate the locations, spacing, amount, and layout of sprinkler heads and water lines to cover the agricultural fields. This research project provides scientific guidance to Mississippi farmers for a precision agricultural irrigation practice.

Keywords: drone images, agriculture, irrigation, geospatial analysis, photogrammetric measurements

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5469 The Residential Subdivision under the Influence of the Unfinished Densification, Case Study for Subdivisions in Setif, Algeria

Authors: Lacheheb Dhia Eddine Zakaria, Ballout Amor

Abstract:

Today, it is necessary to be thrifty for its planet, on one hand the space being a rare, nonrenewable resource, and on the other hand the ecological, economic and social cost of the urban sprawl. It is commonly asserted that the promotion of a more compact and dense city has a positive effect in terms of public costs of investment, functioning and costs for the citizens and the users of the city. It is clear that the modes urban development management have to evolve profoundly, in particular towards a densification favourable to the raising of the urban quality through an ideal urban density on the scale of the individual housing estate. The lot as an individual housing estate was adopted as an alternative development model to the collective housing, thought in an anthropocentric perspective to emerge as a quality model where the density plays an important role, by being included in operations of a global coherence, in an optimal organization without forgetting the main importance of the deadlines of construction and the finalization of the works. The image of eternal construction site inflicted to our cities explains the renewed interest for the application of the regulatory framework and the completion of these limited operations without global coherence, which are summed up in our case to a ground cut in plots of land, sold then built independently without being finished, and support the relevance of the essential question of the improvement of the outside aspect bound to the appearance which can be revealed as a so important factor for a better use and a better acceptance of its housing environment, that the ratio of a number of houses on a plot of land or the number of square meters by house. To demonstrate the impact of the completion degree of the subdivision dwellings, roads system and urban public utilities on the density or the densification and therefore on the urban quality, we studied two residential subdivisions, the private subdivision Sellam and the subdivision El Imane with a common situation, and a different land surface, density and cutting, being occupied by various social classes, with different needs and different household average size. The approach of this work is based on the typo morphological analysis to reveal the differences in the degrees of completions of the subdivision’s built environment and on the investigation, by a household’s survey, to demonstrate importance of the degree of completion and to reveal the conditions of qualitative densification favourable and convenient to a better subdivision’s appropriation.

Keywords: subdivision, degree of completion, densification, urban quality

Procedia PDF Downloads 363
5468 The Impact of Work Stress on Professionals' Life and Health: The Usage of Instant Messaging Applications

Authors: Pui-Lai To, Chechen Liao, Ming-Chi Sung

Abstract:

Work and family life are the most important areas for men and women today. Every professional is required to meet and fulfill the responsibilities of work and family roles. Although the development and popularity of communication technology bring a lot of benefits, including effective and efficient communication, may also generate conflicts between work and family life. Since mobile devices and the applications of mobile devices, such as instant messages, are ubiquitous, the boundaries of work and family roles are increasingly blurred. Professionals may be in the risk of work over-loading and work-family conflict. This study examines the impact of work stress on professionals’ life and health in the context of instant messaging application of smart phone. This study uses a web-based questionnaire to collect samples. The questionnaires are sent via virtual community sites, instant messaging applications, and e-mail. The study develops and empirically validates a work-family conflict model by integrating the pressure theory and technostress factors. The causal relationship between variables in the research model is tested. In terms of data analysis, Partial Least Square (PLS) in Structural Equation Modeling (SEM) is used for sample analysis and research model testing. The results of this study are as follows. First, both the variables of work-related stress and technological violations positively affect the work-family conflict. Second, both the variables of work-loading and technology-overloading have no effect on work-family conflict. Third, work-family conflict has negative effect on job satisfaction, family satisfaction, physical health, and mental health.

Keywords: mental health, physical health, technostress, work-family conflict, work-related stress

Procedia PDF Downloads 280
5467 Bacterio-Algal Microbial Fuel Cells for Sustainable Power Production, Wastewater Treatment, and Desalination

Authors: Ann D. Christy, Beenish Saba

Abstract:

The Microbial fuel Cell (MFC) is a successful integrated technology for power production and wastewater treatment. MFCs are recognized for their dual function, but research in this field is still ongoing to increase efficiency and power output. One such effort is successful integration of phototrophic and autotrophic microorganisms to create bacterio-algal MFCs for sustainable electricity production along with wastewater treatment and algal biomass production. An MFC is typically configured with an anaerobic anodic chamber containing exoelectrogenic microorganisms separated by a cation exchange membrane from an adjacent aerobic cathodic chamber. The two electrodes are connected by an external circuit. This conventional MFC can be converted into a phototrophic MFC by introducing photosynthetic microorganisms into the cathode chamber. This study examines adding a third desalination chamber to a two-chamber bacterio-algal MFC. Successful results have been observed from these three-chamber MFCs demonstrating wastewater treatment in the anodic chamber, phototrophic algal growth in the cathodic chamber, and desalination in the middle chamber. The present article will summarize successful results of the bacterio-algal fuel cells and offer insights about the mechanisms involved. Tables summarizing the input substrate along with optimized operational conditions and output performance in terms of power production and efficiencies of water and wastewater treatment will be presented. The negative impacts and challenges will be discussed, along with possible future research directions. Results suggest that the three chamber bacterio-algal desalination cell has potential as a feasible technology for power production, wastewater treatment and desalination, but it needs further investigation under optimized conditions.

Keywords: bacterio-algal MFC, three chamber, microbial fuel cell, wastewater treatment and desalination

Procedia PDF Downloads 350
5466 Anti-Forensic Countermeasure: An Examination and Analysis Extended Procedure for Information Hiding of Android SMS Encryption Applications

Authors: Ariq Bani Hardi

Abstract:

Empowerment of smartphone technology is growing very rapidly in various fields of science. One of the mobile operating systems that dominate the smartphone market today is Android by Google. Unfortunately, the expansion of mobile technology is misused by criminals to hide the information that they store or exchange with each other. It makes law enforcement more difficult to prove crimes committed in the judicial process (anti-forensic). One of technique that used to hide the information is encryption, such as the usages of SMS encryption applications. A Mobile Forensic Examiner or an investigator should prepare a countermeasure technique if he finds such things during the investigation process. This paper will discuss an extension procedure if the investigator found unreadable SMS in android evidence because of encryption. To define the extended procedure, we create and analyzing a dataset of android SMS encryption application. The dataset was grouped by application characteristics related to communication permissions, as well as the availability of source code and the documentation of encryption scheme. Permissions indicate the possibility of how applications exchange the data and keys. Availability of the source code and the encryption scheme documentation can show what the cryptographic algorithm specification is used, how long the key length, how the process of key generation, key exchanges, encryption/decryption is done, and other related information. The output of this paper is an extended or alternative procedure for examination and analysis process of android digital forensic. It can be used to help the investigators while they got a confused cause of SMS encryption during examining and analyzing. What steps should the investigator take, so they still have a chance to discover the encrypted SMS in android evidence?

Keywords: anti-forensic countermeasure, SMS encryption android, examination and analysis, digital forensic

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5465 The Growth Role of Natural Gas Consumption for Developing Countries

Authors: Tae Young Jin, Jin Soo Kim

Abstract:

Carbon emissions have emerged as global concerns. Intergovernmental Panel of Climate Change (IPCC) have published reports about Green House Gases (GHGs) emissions regularly. United Nations Framework Convention on Climate Change (UNFCCC) have held a conference yearly since 1995. Especially, COP21 held at December 2015 made the Paris agreement which have strong binding force differently from former COP. The Paris agreement was ratified as of 4 November 2016, they finally have legal binding. Participating countries set up their own Intended Nationally Determined Contributions (INDC), and will try to achieve this. Thus, carbon emissions must be reduced. The energy sector is one of most responsible for carbon emissions and fossil fuels particularly are. Thus, this paper attempted to examine the relationship between natural gas consumption and economic growth. To achieve this, we adopted the Cobb-Douglas production function that consists of natural gas consumption, economic growth, capital, and labor using dependent panel analysis. Data were preprocessed with Principal Component Analysis (PCA) to remove cross-sectional dependency which can disturb the panel results. After confirming the existence of time-trended component of each variable, we moved to cointegration test considering cross-sectional dependency and structural breaks to describe more realistic behavior of volatile international indicators. The cointegration test result indicates that there is long-run equilibrium relationship between selected variables. Long-run cointegrating vector and Granger causality test results show that while natural gas consumption can contribute economic growth in the short-run, adversely affect in the long-run. From these results, we made following policy implications. Since natural gas has positive economic effect in only short-run, the policy makers in developing countries must consider the gradual switching of major energy source, from natural gas to sustainable energy source. Second, the technology transfer and financing business suggested by COP must be accelerated. Acknowledgement—This work was supported by the Energy Efficiency & Resources Core Technology Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) granted financial resource from the Ministry of Trade, Industry & Energy, Republic of Korea (No. 20152510101880) and by the National Research Foundation of Korea Grant funded by the Korean Government (NRF-205S1A3A2046684).

Keywords: developing countries, economic growth, natural gas consumption, panel data analysis

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5464 Characteristics and Drivers of Greenhouse Gas (GHG) emissions from China’s Manufacturing Industry: A Threshold Analysis

Authors: Rong Yuan, Zhao Tao

Abstract:

Only a handful of literature have used to non-linear model to investigate the influencing factors of greenhouse gas (GHG) emissions in China’s manufacturing sectors. And there is a limit in investigating quantitatively and systematically the mechanism of correlation between economic development and GHG emissions considering inherent differences among manufacturing sub-sectors. Considering the sectorial characteristics, the manufacturing sub-sectors with various impacts of output on GHG emissions may be explained by different development modes in each manufacturing sub-sector, such as investment scale, technology level and the level of international competition. In order to assess the environmental impact associated with any specific level of economic development and explore the factors that affect GHG emissions in China’s manufacturing industry during the process of economic growth, using the threshold Stochastic Impacts by Regression on Population, Affluence and Technology (STIRPAT) model, this paper investigated the influence impacts of GHG emissions for China’s manufacturing sectors of different stages of economic development. A data set from 28 manufacturing sectors covering an 18-year period was used. Results demonstrate that output per capita and investment scale contribute to increasing GHG emissions while energy efficiency, R&D intensity and FDI mitigate GHG emissions. Results also verify the nonlinear effect of output per capita on emissions as: (1) the Environmental Kuznets Curve (EKC) hypothesis is supported when threshold point RMB 31.19 million is surpassed; (2) the driving strength of output per capita on GHG emissions becomes stronger as increasing investment scale; (3) the threshold exists for energy efficiency with the positive coefficient first and negative coefficient later; (4) the coefficient of output per capita on GHG emissions decreases as R&D intensity increases. (5) FDI shows a reduction in elasticity when the threshold is compassed.

Keywords: China, GHG emissions, manufacturing industry, threshold STIRPAT model

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5463 Investigation on Biomass as an Alternate Source for Power Generation

Authors: Narsimhulu Sanke, D. N. Reddy

Abstract:

The purpose of the paper is to discuss the biomass as a renewable source of energy for power generation. The setup is designed and fabricated in the Centre for Energy Technology (CET) and four different fuels are tested in the laboratory, but here the focus is on wood blocks (fuel) combustion with temperature, gas composition percentage by volume and the heating values.

Keywords: biomass, downdraft gasifier, power generation, renewable energy sources

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5462 Performance of the Photovoltaic Module under Different Shading Patterns

Authors: E. T. El Shenawy, O. N. A. Esmail, Adel A. Elbaset, Hesham F. A. Hamed

Abstract:

Generation of the electrical energy based on photovoltaic (PV) technology has been increased over the world due to either the continuous reduction in the traditional energy sources in addition to the pollution problems related to their usage, or the clean nature and safe usage of the PV technology. Also, PV systems can generate clean electricity in the site of use without any transmission, which can be considered cost effective than other generation systems. The performance of the PV system is highly affected by the amount of solar radiation incident on it. Completely or partially shaded PV systems can affect its output. The PV system can be shaded by trees, buildings, dust, incorrect system configuration, or other obstacles. The present paper studies the effect of the partial shading on the performance of a thin film PV module under climatic conditions of Cairo, Egypt. This effect was measured and evaluated according to practical measurement of the characteristic curves such as current-voltage and power-voltage for two identical PV modules (with and without shading) placed at the same time on one mechanical structure for comparison. The measurements have been carried out for the following shading patterns; half cell (bottom, middle, and top of the PV module); complete cell; and two adjacent cells. The results showed that partially shading the PV module changes the shapes of the I-V and P-V curves and produces more than one maximum power point, that can disturb the traditional maximum power point trackers. Also, the output power from the module decreased according to the incomplete solar radiation reaching the PV module due to shadow patterns. The power loss due shading was 7%, 22%, and 41% for shading of half-cell, one cell, and two adjacent cells of the PV module, respectively.

Keywords: I-V measurements, PV module characteristics, PV module power loss, PV module shading

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5461 Improving the Crashworthiness Characteristics of Long Steel Circular Tubes Subjected to Axial Compression by Inserting a Helical Spring

Authors: Mehdi Tajdari, Farzad Mokhtarnejad, Fatemeh Moradi, Mehdi Najafizadeh

Abstract:

Nowadays, energy absorbing devices have been widely used in all vehicles and moving parts such as railway couches, aircraft, ships and lifts. The aim is to protect these structures from serious damages while subjected to impact loads, or to minimize human injuries while collision is occurred in transportation systems. These energy-absorbing devices can dissipate kinetic energy in a wide variety of ways like friction, facture, plastic bending, crushing, cyclic plastic deformation and metal cutting. On the other hand, various structures may be used as collapsible energy absorbers. Metallic cylindrical tubes have attracted much more attention due to their high stiffness and strength combined with the low weight and ease of manufacturing process. As a matter of fact, favorable crash worthiness characteristics for energy dissipation purposes can be achieved from axial collapse of tubes while they crush progressively in symmetric modes. However, experimental and theoretical results have shown that depending on various parameters such as tube geometry, material properties of tube, boundary and loading conditions, circular tubes buckle in different modes of deformation, namely, diamond and Euler collapsing modes. It is shown that when the tube length is greater than the critical length, the tube deforms in overall Euler buckling mode, which is an inefficient mode of energy absorption and needs to be avoided in crash worthiness applications. This study develops a new method with the aim of improving energy absorption characteristics of long steel circular tubes. Inserting a helical spring into the tubes is proved experimentally to be an efficient solution. In fact when a long tube is subjected to axial compression load, the spring prevents of undesirable Euler or diamond collapsing modes. This is because the spring reinforces the internal wall of tubes and it causes symmetric deformation in tubes. In this research three specimens were prepared and three tests were performed. The dimensions of tubes were selected so that in axial compression load buckling is occurred. In the second and third tests a spring was inserted into tubes and they were subjected to axial compression load in quasi-static and impact loading, respectively. The results showed that in the second and third tests buckling were not happened and the tubes deformed in symmetric modes which are desirable in energy absorption.

Keywords: energy absorption, circular tubes, collapsing deformation, crashworthiness

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5460 The Development of E-Commerce in Mexico: An Econometric Analysis

Authors: Alma Lucero Ortiz, Mario Gomez

Abstract:

Technological advances contribute to the well-being of humanity by allowing man to perform in a more efficient way. Technology offers tangible advantages to countries with the adoption of information technologies, communication, and the Internet in all social and productive sectors. The Internet is a networking infrastructure that allows the communication of people throughout the world, exceeding the limits of time and space. Nowadays the internet has changed the way of doing business leading to a digital economy. In this way, e-commerce has emerged as a commercial transaction conducted over the Internet. For this inquiry e-commerce is seen as a source of economic growth for the country. Thereby, these research aims to answer the research question, which are the main variables that have affected the development of e-commerce in Mexico. The research includes a period of study from 1990 to 2017. This inquiry aims to get insight on how the independent variables influence the e-commerce development. The independent variables are information infrastructure construction, urbanization level, economic level, technology level, human capital level, educational level, standards of living, and price index. The results suggest that the independent variables have an impact on development of the e-commerce in Mexico. The present study is carried out in five parts. After the introduction, in the second part, a literature review about the main qualitative and quantitative studies to measure the variables subject to the study is presented. After, an empirical study is applied through time series data, and to process the data an econometric model is performed. In the fourth part, the analysis and discussion of results are presented, and finally, some conclusions are included.

Keywords: digital economy, e-commerce, econometric model, economic growth, internet

Procedia PDF Downloads 222
5459 Predictions of Thermo-Hydrodynamic State for Single and Three Pads Gas Foil Bearings Operating at Steady-State Based on Multi-Physics Coupling Computer Aided Engineering Simulations

Authors: Tai Yuan Yu, Pei-Jen Wang

Abstract:

Oil-free turbomachinery is considered one of the critical technologies for future green power generation systems as rotor machinery systems. Oil-free technology allows clean, compact, and maintenance-free working, and gas foil bearings, abbreviated as GFBs, are important for the technology. Since the first applications in the auxiliary power units and air cycle machines in the 1970s, obvious improvement has been created to the computational models for dynamic rotor behavior. However, many technical issues are still poorly understood or remain unsolved, and some of those are thermal management and the pattern of how pressure will be distributed in bearing clearance. This paper presents a three-dimensional, abbreviated as 3D, fluid-structure interaction model of single pad foil bearings and three pad foil bearings to predict bearing working behavior that researchers could compare characteristics of those. The coupling analysis model involves dynamic working characteristics applied to all the gas film and mechanical structures. Therefore, the elastic deformation of foil structure and the hydrodynamic pressure of gas film can both be calculated by a finite element method program. As a result, the temperature distribution pattern could also be iteratively solved by coupling analysis. In conclusion, the working fluid state in a gas film of various pad forms of bearings working characteristic at constant rotational speed for both can be solved for comparisons with the experimental results.

Keywords: fluid-structure interaction, multi-physics simulations, gas foil bearing, oil-free, transient thermo-hydrodynamic

Procedia PDF Downloads 156
5458 Understanding Strategic Engagement on the Conversation Table: Countering Terrorism in Nigeria

Authors: Anisah Ari

Abstract:

Effects of organized crime permeate all facets of life, including public health, socio-economic endeavors, and human security. If any element of this is affected, it impacts large-scale national and global interest. Seeking to address terrorist networks through technical thinking is like trying to kill a weed by just cutting off its branches. It will re-develop and expand in proportions beyond one’s imagination, even in horrific ways that threaten human security. The continent of Africa has been bedeviled by this menace, with little or no solution to the problem. Nigeria is dealing with a protracted insurgency that is perpetrated by a sect against any form of westernization. Reimagining approaches to dealing with pressing issues like terrorism may require engaging the right set of people in the conversation for any sustainable change. These are people who have lived through the daily effects of the violence that ensues from the activities of terrorist activities. Effective leadership is required for an inclusive process, where spaces are created for diverse voices to be heard, and multiple perspectives are listened to, and not just heard, that supports a determination of the realistic outcome. Addressing insurgency in Nigeria has experienced a lot of disinformation and uncertainty. This may be in part due to poor leadership or an iteration of technical solutions to adaptive challenge peacemaking efforts in Nigeria has focused on behaviors, attitudes and practices that contribute to violence. However, it is important to consider the underlying issues that build-up, ignite and fan the flames of violence—looking at conflict as a complex system, issues like climate change, low employment rates, corruption and the impunity of discrimination due to ethnicity and religion. This article will be looking at an option of the more relational way of addressing insurgency through adaptive approaches that embody engagement and solutions with the people rather than for the people. The construction of a local turn in peacebuilding is informed by the need to create a locally driven and sustained peace process that embodies the culture and practices of the people in enacting an everyday peace beyond just a perennial and universalist outlook. A critical analysis that explores the socially identified individuals and situations will be made, considering the more adaptive approach to a complex existential challenge rather than a universalist frame. Case Study and Ethnographic research approach to understand what other scholars have documented on the matter and also a first-hand understanding of the experiences and viewpoints of the participants.

Keywords: terrorism, adaptive, peace, culture

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5457 Effect of Packaging Material and Water-Based Solutions on Performance of Radio Frequency Identification for Food Packaging Applications

Authors: Amelia Frickey, Timothy (TJ) Sheridan, Angelica Rossi, Bahar Aliakbarian

Abstract:

The growth of large food supply chains demanded improved end-to-end traceability of food products, which has led to companies being increasingly interested in using smart technologies such as Radio Frequency Identification (RFID)-enabled packaging to track items. As technology is being widely used, there are several technological or economic issues that should be overcome to facilitate the adoption of this track-and-trace technology. One of the technological challenges of RFID technology is its sensitivity to different environmental form factors, including packaging materials and the content of the packaging. Although researchers have assessed the performance loss due to the proximity of water and aqueous solutions, there is still the need to further investigate the impacts of food products on the reading range of RFID tags. However, to the best of our knowledge, there are not enough studies to determine the correlation between RFID tag performance and food beverages properties. The goal of this project was to investigate the effect of the solution properties (pH and conductivity) and different packaging materials filled with food-like water-based solutions on the performance of an RFID tag. Three commercially available ultra high-frequency RFID tags were placed on three different bottles and filled with different concentrations of water-based solutions, including sodium chloride, citric acid, sucrose, and ethanol. Transparent glass, Polyethylneterephtalate (PET), and Tetrapak® were used as the packaging materials commonly used in the beverage industries. Tag readability (Theoretical Read Range, TRR) and sensitivity (Power on Tag Forward, PoF) were determined using an anechoic chamber. First, the best place to attach the tag for each packaging material was investigated using empty and water-filled bottles. Then, the bottles were filled with the food-like solutions and tested with the three different tags and the PoF and TRR at the fixed frequency of 915MHz. In parallel, the pH and conductivity of solutions were measured. The best-performing tag was then selected to test the bottles filled with wine, orange, and apple juice. Despite various solutions altering the performance of each tag, the change in tag performance had no correlation with the pH or conductivity of the solution. Additionally, packaging material played a significant role in tag performance. Each tag tested performed optimally under different conditions. This study is the first part of comprehensive research to determine the regression model for the prediction of tag performance behavior based on the packaging material and the content. More investigations, including more tags and food products, are needed to be able to develop a robust regression model. The results of this study can be used by RFID tag manufacturers to design suitable tags for specific products with similar properties.

Keywords: smart food packaging, supply chain management, food waste, radio frequency identification

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5456 Improvement of the Mechanical Behavior of an Environmental Concrete Based on Demolished

Authors: Larbi Belagraa

Abstract:

The universal need to conserve resources, protect the environment and use energy efficiently must necessarily be felt in the field of concrete technology. The recycling of construction and demolition waste as a source of aggregates for the production of concrete has attracted growing interest from the construction industry. In Algeria, the depletion of natural deposits of aggregates and the difficulties in setting up new quarries; makes it necessary to seek new sources of supply, to meet the need for aggregates for the major projects launched by the Algerian government in the last decades. In this context, this work is a part of the approach to provide answers to concerns about the lack of aggregates for concrete. It also aims to develop the inert fraction of demolition materials and mainly concrete construction demolition waste(C&D) as a source of aggregates for the manufacture of new hydraulic concretes based on recycled aggregates. This experimental study presents the results of physical and mechanical characterizations of natural and recycled aggregates, as well as their influence on the properties of fresh and hardened concrete. The characterization of the materials used has shown that the recycled aggregates have heterogeneity, a high water absorption capacity, and a medium quality hardness. However, the limits prescribed by the standards in force do not disqualify these materials of use for application as recycled aggregate concrete type (RAC). The results obtained from the present study show that acceptable mechanical, compressive, and flexural strengths of RACs are obtained using Superplasticizer SP 45 and 5% replacement of cement with silica fume based on recycled aggregates, compared to those of natural concretes. These mechanical performances demonstrate a characteristic resistance at 28 days in compression within the limits of 30 to 40 MPa without any particular suitable technology .to be adapted in the case.

Keywords: recycled aggregates, concrete(RAC), superplasticizer, silica fume, compressive strength

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5455 Human Interaction Skills and Employability in Courses with Internships: Report of a Decade of Success in Information Technology

Authors: Filomena Lopes, Miguel Magalhaes, Carla Santos Pereira, Natercia Durao, Cristina Costa-Lobo

Abstract:

The option to implement curricular internships with undergraduate students is a pedagogical option with some good results perceived by academic staff, employers, and among graduates in general and IT (Information Technology) in particular. Knowing that this type of exercise has never been so relevant, as one tries to give meaning to the future in a landscape of rapid and deep changes. We have as an example the potential disruptive impact on the jobs of advances in robotics, artificial intelligence and 3-D printing, which is a focus of fierce debate. It is in this context that more and more students and employers engage in the pursuit of career-promoting responses and business development, making their investment decisions of training and hiring. Three decades of experience and research in computer science degree and in information systems technologies degree at the Portucalense University, Portuguese private university, has provided strong evidence of its advantages. The Human Interaction Skills development as well as the attractiveness of such experiences for students are topics assumed as core in the Ccnception and management of the activities implemented in these study cycles. The objective of this paper is to gather evidence of the Human Interaction Skills explained and valued within the curriculum internship experiences of IT students employability. Data collection was based on the application of questionnaire to intern counselors and to students who have completed internships in these undergraduate courses in the last decade. The trainee supervisor, responsible for monitoring the performance of IT students in the evolution of traineeship activities, evaluates the following Human Interaction Skills: Motivation and interest in the activities developed, interpersonal relationship, cooperation in company activities, assiduity, ease of knowledge apprehension, Compliance with norms, insertion in the work environment, productivity, initiative, ability to take responsibility, creativity in proposing solutions, and self-confidence. The results show that these undergraduate courses promote the development of Human Interaction Skills and that these students, once they finish their degree, are able to initiate remunerated work functions, mainly by invitation of the institutions in which they perform curricular internships. Findings obtained from the present study contribute to widen the analysis of its effectiveness in terms of future research and actions in regard to the transition from Higher Education pathways to the Labour Market.

Keywords: human interaction skills, employability, internships, information technology, higher education

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5454 Conservation of Sea Turtle in Cox’s Bazar- Teknaf Peninsula and Sonadia Island Ecologically Critical Area (ECA) of Bangladesh

Authors: Pronob Kumar Mozumder M. Nazrul Islam, M. Abdur Rob Mollah

Abstract:

This study was conducted in Cox’s Bazar-Teknaf Peninsula and Sonadia Island Ecologically Critical Areas during the period of October, 2011 to June, 2013. Six species of marine turtle are found in the Indian Ocean. Among them, olive ridley (Lepidochelys olivacea) listed as endangered in the IUCN Red List of Threatened Species. Marine turtle populations in the Indian Ocean have been depleted through long-term exploitation of eggs and adults, incidental capture (fisheries bycatch) and many other sources of mortality. The specific objective of the study was to conserve the sea turtles specially the olive ridley (Lepidochelys olivacea) with a view to contribute towards protection of the turtle species from extinction and to facilitate hatching of eggs through providing protection to turtle eggs or nest through ex-situ conservation efforts. In order to achieve the desired outputs and success, a total of five turtle hatcheries were established at Pechardwip, Khurermukh, Hazompara, Bodormokam, and Sonadia Eastpara sites. In total, 31,853 eggs were collected from 260 nests and were transferred to five hatcheries. The number of eggs/nest varied from 38 to 190 with an average clutch size of 122 eggs/ nest. Hatching of eggs took place during January to June with a peak in April. Sea turtle eggs were incubated by metabolic heat and the heat of the sun. The incubation period of turtle eggs in Cox’s Bazar-Teknaf Peninsula and Sonadia Island ECAs extended from 54 to 75 days depending on the month with an average of 66 days. During study period the temperature in the ECAs varied between 10.5-34.5°C. A total of 27,937 hatchlings of turtle were produced from the five hatcheries and all the hatchlings produced were released into the sea. Hatching rates varied from 74-98 % depending on the location and months with an average of 88 %. Sea turtles spend the majority of their lives in the sea, only emerging on beaches to nest. Despite the intense conservation efforts on the beaches, some populations have still declined to the edge of extinction. So proper conservation and awareness measure should be taken for prevention of turtle extinction.

Keywords: conservation of sea turtle, Bangladesh, ecologically critical area, ECA, Lepidochelys olivacea

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5453 Integration of Technology through Instructional Systems Design

Authors: C. Salis, D. Zedda, M. F. Wilson

Abstract:

The IDEA project was conceived for teachers who are interested in enhancing their capacity to effectively implement the use of specific technologies in their teaching practice. Participating teachers are coached and supported as they explore technologies applied to the educational context. They access tools such as the technological platform developed by our team. Among the platform functionalities, teachers access an instructional systems design (ISD) tool (learning designer) that was adapted to the needs of our project. The tool is accessible from computers or mobile devices and used in association with other technologies to create new, meaningful learning environments. The objective of an instructional systems design is to guarantee the quality and effectiveness of education and to enhance learning. This goal involves both teachers who want to become more efficient in transferring knowledge or skills and students as the final recipient of their teaching. The use of Blooms’s taxonomy enables teachers to classify the learning objectives into levels of complexity and specificity, thus making it possible to highlight the kind of knowledge teachers would like their students to reach. The fact that the instructional design features can be visualized through the IDEA platform is a guarantee for those who are looking for specific educational materials to be used in their lessons. Despite the benefits offered, a number of teachers are reluctant to use ISD because the preparatory work of having to thoroughly analyze the teaching/learning objectives, the planning of learning material, assessment activities, etc., is long and felt to be time-consuming. This drawback is minimized using a learning designer, as the tool facilitates to reuse of the didactic contents having a clear view of the processes of analysis, planning, and production of educational or testing materials uploaded on our platform. In this paper, we shall present the feedback of the teachers who used our tool in their didactic.

Keywords: educational benefits, educational quality, educational technology, ISD tool

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5452 Evaluation of NoSQL in the Energy Marketplace with GraphQL Optimization

Authors: Michael Howard

Abstract:

The growing popularity of electric vehicles in the United States requires an ever-expanding infrastructure of commercial DC fast charging stations. The U.S. Department of Energy estimates 33,355 publicly available DC fast charging stations as of September 2023. In 2017, 115,370 gasoline stations were operating in the United States, much more ubiquitous than DC fast chargers. Range anxiety is an important impediment to the adoption of electric vehicles and is even more relevant in underserved regions in the country. The peer-to-peer energy marketplace helps fill the demand by allowing private home and small business owners to rent their 240 Volt, level-2 charging facilities. The existing, publicly accessible outlets are wrapped with a Cloud-connected microcontroller managing security and charging sessions. These microcontrollers act as Edge devices communicating with a Cloud message broker, while both buyer and seller users interact with the framework via a web-based user interface. The database storage used by the marketplace framework is a key component in both the cost of development and the performance that contributes to the user experience. A traditional storage solution is the SQL database. The architecture and query language have been in existence since the 1970s and are well understood and documented. The Structured Query Language supported by the query engine provides fine granularity with user query conditions. However, difficulty in scaling across multiple nodes and cost of its server-based compute have resulted in a trend in the last 20 years towards other NoSQL, serverless approaches. In this study, we evaluate the NoSQL vs. SQL solutions through a comparison of Google Cloud Firestore and Cloud SQL MySQL offerings. The comparison pits Google's serverless, document-model, non-relational, NoSQL against the server-base, table-model, relational, SQL service. The evaluation is based on query latency, flexibility/scalability, and cost criteria. Through benchmarking and analysis of the architecture, we determine whether Firestore can support the energy marketplace storage needs and if the introduction of a GraphQL middleware layer can overcome its deficiencies.

Keywords: non-relational, relational, MySQL, mitigate, Firestore, SQL, NoSQL, serverless, database, GraphQL

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5451 Hydrogeophysical Investigations And Mapping of Ingress Channels Along The Blesbokspruit Stream In The East Rand Basin Of The Witwatersrand, South Africa

Authors: Melvin Sethobya, Sithule Xanga, Sechaba Lenong, Lunga Nolakana, Gbenga Adesola

Abstract:

Mining has been the cornerstone of the South African economy for the last century. Most of the gold mining in South Africa was conducted within the Witwatersrand basin, which contributed to the rapid growth of the city of Johannesburg and capitulated the city to becoming the business and wealth capital of the country. But with gradual depletion of resources, a stoppage in the extraction of underground water from mines and other factors relating to survival of the mining operations over a lengthy period, most of the mines were abandoned and left to pollute the local waterways and groundwater with toxins, heavy metal residue and increased acid mine drainage ensued. The Department of Mineral Resources and Energy commissioned a project whose aim is to monitor, maintain, and mitigate the adverse environmental impacts of polluted water mine water flowing into local streams affecting local ecosystems and livelihoods downstream. As part of mitigation efforts, the diagnosis and monitoring of groundwater or surface water polluted sites has become important. Geophysical surveys, in particular, Resistivity and Magnetics surveys, were selected as some of most suitable techniques for investigation of local ingress points along of one the major streams cutting through the Witwatersrand basin, namely the Blesbokspruit, which is found in the eastern part of the basin. The aim of the surveys was to provide information that could be used to assist in determining possible water loss/ ingress from the Blesbokspriut stream. Modelling of geophysical surveys results offered an in-depth insight into the interaction and pathways of polluted water through mapping of possible ingress channels near the Blesbokspruit. The resistivity - depth profile of the surveyed site exhibit a three(3) layered model with low resistivity values (10 to 200 Ω.m) overburden, which is underlain by a moderate resistivity weathered layer (>300 Ω.m), which sits on a more resistive crystalline bedrock (>500 Ω.m). Two locations of potential ingress channels were mapped across the two traverses at the site. The magnetic survey conducted at the site mapped a major NE-SW trending regional linearment with a strong magnetic signature, which was modeled to depth beyond 100m, with the potential to act as a conduit for dispersion of stream water away from the stream, as it shared a similar orientation with the potential ingress channels as mapped using the resistivity method.

Keywords: eletrictrical resistivity, magnetics survey, blesbokspruit, ingress

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5450 Understanding Magnetic Properties of Cd1-xSnxCr2Se4 Using Local Structure Probes

Authors: P. Suchismita Behera, V. G. Sathe, A. K. Nigam, P. A. Bhobe

Abstract:

Co-existence of long-range ferromagnetism and semi-conductivity with correlated behavior of structural, magnetic, optical and electrical properties in various sites doping at CdCr2Se4 makes it a most promising candidate for spin-based electronic applications and magnetic devices. It orders ferromagnetically below TC = 130 K with a direct band gap of ~ 1.5 eV. The magnetic ordering is believed to result from strong competition between the direct antiferromagnetic Cr-Cr spin couplings and the ferromagnetic Cr-Se-Cr exchange interactions. With an aim of understanding the influence of crystal structure on its magnetic properties without disturbing the magnetic site, we investigated four compositions with 3%, 5%, 7% and 10% of Sn-substitution at Cd-site. Partial substitution of Cd2+ (0.78Å) by small sized nonmagnetic ion, Sn4+ (0.55Å), is expected to bring about local lattice distortion as well as a change in electronic charge distribution. The structural disorder would affect the Cd/Sn – Se bonds thus affecting the Cr-Cr and Cr-Se-Cr bonds. Whereas, the charge imbalance created due to Sn4+ substitution at Cd2+ leads to the possibility of Cr mixed valence state. Our investigation of the local crystal structure using the EXAFS, Raman spectroscopy and magnetic properties using SQUID magnetometry of the Cd1-xSnxCr2Se4 series reflects this premise. All compositions maintain the Fd3m cubic symmetry with tetrahedral distribution of Sn at Cd-site, as confirmed by XRD analysis. Lattice parameters were determined from the Rietveld refinement technique of the XRD data and further confirmed from the EXAFS spectra recorded at Cr K-edge. Presence of five Raman-active phonon vibrational modes viz. (T2g (1), T2g (2), T2g (3), Eg, A1g) in the Raman spectra further confirms the crystal symmetry. Temperature dependence of the Raman data provides interesting insight to the spin– phonon coupling, known to dominate the magneto-capacitive properties in the parent compound. Below the magnetic ordering temperature, the longitudinal damping of Eg mode associated with Se-Cd/Sn-Se bending and T2g (2) mode associated to Cr-Se-Cr interaction, show interesting deviations with respect to increase in Sn substitution. Besides providing the estimate of TC, the magnetic measurements recorded as a function of field provide the values of total magnetic moment for all the studied compositions indicative of formation of multiple Cr valences.

Keywords: exchange interactions, EXAFS, ferromagnetism, Raman spectroscopy, spinel chalcogenides

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5449 Free-Standing Pd-Based Metallic Glass Membranes for MEMS Applications

Authors: Wei-Shan Wang, Klaus Vogel, Felix Gabler, Maik Wiemer, Thomas Gessner

Abstract:

Metallic glasses, which are free of grain boundaries, have superior properties including large elastic limits, high strength, and excellent wear and corrosion resistance. Therefore, bulk metallic glasses (BMG) and thin film metallic glasses (TFMG) have been widely developed and investigated. Among various kinds of metallic glasses, Pd-Cu-Si TFMG, which has lower elastic modulus and better resistance of oxidation and corrosions compared to Zr- and Fe-based TFMGs, can be a promising candidate for MEMS applications. However, the study of Pd-TFMG membrane is still limited. This paper presents free-standing Pd-based metallic glass membranes with large area fabricated on wafer level for the first time. Properties of Pd-Cu-Si thin film metallic glass (TFMG) with various deposition parameters are investigated first. When deposited at 25°C, compressive stress occurs in the Pd76Cu6Si18 thin film regardless of Ar pressure. When substrate temperature is increased to 275°C, the stress state changes from compressive to tensile. Thin film stresses are slightly decreased when Ar pressure is higher. To show the influence of temperature on Pd-TFMGs, thin films without and with post annealing below (275°C) and within (370°C) supercooled liquid region are investigated. Results of XRD and TEM analysis indicate that Pd-TFMGs remain amorphous structure with well-controlled parameters. After verification of amorphous structure of the Pd-TFMGs, free-standing Pd-Cu-Si membranes were fabricated by depositing Pd-Cu-Si thin films directly on 200nm-thick silicon nitride membranes, followed by post annealing and dry etching of silicon nitride layer. Post annealing before SiNx removal is used to further release internal stress of Pd-TFMGs. The edge length of the square membrane ranges from 5 to 8mm. The effect of post annealing on Pd-Cu-Si membranes are discussed as well. With annealing at 370°C for 5 min, Pd-MG membranes are fully distortion-free after removal of SiNx layer. Results show that, by introducing annealing process, the stress-relief, distortion-free Pd-TFMG membranes with large area can be a promising candidate for sensing applications such as pressure and gas sensors.

Keywords: amorphous alloy, annealing, metallic glasses, TFMG membrane

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