Search results for: laser systems
7667 Influence of Measurement System on Negative Bias Temperature Instability Characterization: Fast BTI vs Conventional BTI vs Fast Wafer Level Reliability
Authors: Vincent King Soon Wong, Hong Seng Ng, Florinna Sim
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Negative Bias Temperature Instability (NBTI) is one of the critical degradation mechanisms in semiconductor device reliability that causes shift in the threshold voltage (Vth). However, thorough understanding of this reliability failure mechanism is still unachievable due to a recovery characteristic known as NBTI recovery. This paper will demonstrate the severity of NBTI recovery as well as one of the effective methods used to mitigate, which is the minimization of measurement system delays. Comparison was done in between two measurement systems that have significant differences in measurement delays to show how NBTI recovery causes result deviations and how fast measurement systems can mitigate NBTI recovery. Another method to minimize NBTI recovery without the influence of measurement system known as Fast Wafer Level Reliability (FWLR) NBTI was also done to be used as reference.Keywords: fast vs slow BTI, fast wafer level reliability (FWLR), negative bias temperature instability (NBTI), NBTI measurement system, metal-oxide-semiconductor field-effect transistor (MOSFET), NBTI recovery, reliability
Procedia PDF Downloads 4287666 Characterization of Antibiotic Resistance in Cultivable Enterobacteriaceae Isolates from Different Ecological Niches in the Eastern Cape, South Africa
Authors: Martins A. Adefisoye, Mpaka Lindelwa, Fadare Folake, Anthony I. Okoh
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Evolution and rapid dissemination of antibiotic resistance from one ecosystem to another has been responsible for wide-scale epidemic and endemic spreads of multi-drug resistance pathogens. This study assessed the prevalence of Enterobacteriaceae in different environmental samples, including river water, hospital effluents, abattoir wastewater, animal rectal swabs and faecal droppings, soil, and vegetables, using standard microbiological procedure. The identity of the isolates were confirmed using matrix-assisted laser desorption ionization-time of flight mass spectrophotometry (MALDI-TOF) while the isolates were profiled for resistance against a panel of 16 antibiotics using disc diffusion (DD) test, and the occurrence of resistance genes (ARG) was determined by polymerase chain reactions (PCR). Enterobacteriaceae counts in the samples range as follows: river water 4.0 × 101 – 2.0 × 104 cfu/100 ml, hospital effluents 1.5 × 103 – 3.0 × 107 cfu/100 ml, municipal wastewater 2.3 × 103 – 9.2 × 104 cfu/100 ml, faecal droppings 3.0 × 105 – 9.5 × 106 cfu/g, animal rectal swabs 3.0 × 102 – 2.9 × 107 cfu/ml, soil 0 – 1.2 × 105 cfu/g and vegetables 0 – 2.2 × 107 cfu/g. Of the 700 randomly selected presumptive isolates subjected to MALDI-TOF analysis, 129 (18.4%), 68 (9.7%), 67 (9.5%), 41 (5.9%) were E. coli, Klebsiella spp., Enterobacter spp., and Citrobacter spp. respectively while the remaining isolates belong to other genera not targeted in the study. The DD test shows resistance ranging between 91.6% (175/191) for cefuroxime and (15.2%, 29/191) for imipenem The predominant multiple antibiotic resistance phenotypes (MARP), (GM-AUG-AP-CTX-CXM-CIP-NOR-NI-C-NA-TS-T-DXT) occurred in 9 Klebsiella isolates. The multiple antibiotic resistance indices (MARI) the isolates (range 0.17–1.0) generally showed >95% had MARI above the 0.2 thresholds, suggesting that most of the isolates originate from high-risk environments with high antibiotic use and high selective pressure for the emergence of resistance. The associated ARG in the isolates include: bla TEM 61.9 (65), bla SHV 1.9 (2), bla OXA 8.6 (9), CTX-M-2 8.6 (9), CTX-M-9 6.7 (7), sul 2 26.7 (28), tet A 16.2 (17), tet M 17.1 (18), aadA 59.1 (62), strA 34.3 (36), aac(3)A 19.1 (20), (aa2)A 7.6 (8), and aph(3)-1A 10.5 (11). The results underscore the need for preventative measures to curb the proliferation of antibiotic-resistant bacteria including Enterobacteriaceae to protect public health.Keywords: enterobacteriaceae, antibiotic-resistance, MALDI-TOF, resistance genes, MARP, MARI, public health
Procedia PDF Downloads 1537665 Transformative Leadership and Learning Management Systems Implementation: Leadership Practices in Instructional Design for Online Learning
Authors: Felix Brito
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With the growth of online learning, several higher education institutions have attempted to incorporate technology in their curriculum. Successful technology implementation projects really on technology infrastructure and on the acceptance of education professionals towards innovation. This research study is aimed at illustrating the relevance of the human component in technology implementation projects in higher education by describing the Learning Management System implementation project executed by instructional designers working for a higher education institution in the southeast region of the United States. An analysis of the Transformative Leadership Theory, the Technology Acceptance Model, and the Diffusion of Innovation Process provide the support for a solid understanding of this issue and address recommendations for future technology implementation projects in higher education institutions.Keywords: diffusion of innovation process, instructional design, leadership, learning management systems, online learning, technology acceptance model, transformative leadership theory
Procedia PDF Downloads 3337664 Realistic Testing Procedure of Power Swing Blocking Function in Distance Relay
Authors: Farzad Razavi, Behrooz Taheri, Mohammad Parpaei, Mehdi Mohammadi Ghalesefidi, Siamak Zarei
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As one of the major problems in protecting large-dimension power systems, power swing and its effect on distance have caused a lot of damages to energy transfer systems in many parts of the world. Therefore, power swing has gained attentions of many researchers, which has led to invention of different methods for power swing detection. Power swing detection algorithm is highly important in distance relay, but protection relays should have general requirements such as correct fault detection, response rate, and minimization of disturbances in a power system. To ensure meeting the requirements, protection relays need different tests during development, setup, maintenance, configuration, and troubleshooting steps. This paper covers power swing scheme of the modern numerical relay protection, 7sa522 to address the effect of the different fault types on the function of the power swing blocking. In this study, it was shown that the different fault types during power swing cause different time for unblocking distance relay.Keywords: power swing, distance relay, power system protection, relay test, transient in power system
Procedia PDF Downloads 3867663 Conceptualizing IoT Based Framework for Enhancing Environmental Accounting By ERP Systems
Authors: Amin Ebrahimi Ghadi, Morteza Moalagh
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This research is carried out to find how a perfect combination of IoT architecture (Internet of Things) and ERP system can strengthen environmental accounting to incorporate both economic and environmental information. IoT (e.g., sensors, software, and other technologies) can be used in the company’s value chain from raw material extraction through materials processing, manufacturing products, distribution, use, repair, maintenance, and disposal or recycling products (Cradle to Grave model). The desired ERP software then will have the capability to track both midpoint and endpoint environmental impacts on a green supply chain system for the whole life cycle of a product. All these enable environmental accounting to calculate, and real-time analyze the operation environmental impacts, control costs, prepare for environmental legislation and enhance the decision-making process. In this study, we have developed a model on how to use IoT devices in life cycle assessment (LCA) to gather emissions, energy consumption, hazards, and wastes information to be processed in different modules of ERP systems in an integrated way for using in environmental accounting to achieve sustainability.Keywords: ERP, environmental accounting, green supply chain, IOT, life cycle assessment, sustainability
Procedia PDF Downloads 1747662 Securing Healthcare IoT Devices and Enabling SIEM Integration: Addressing
Authors: Mubarak Saadu Nabunkari, Abdullahi Abdu Ibrahim, Muhammad Ilyas
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This study looks at how Internet of Things (IoT) devices are used in healthcare to monitor and treat patients better. However, using these devices in healthcare comes with security problems. The research explores using Security Information and Event Management (SIEM) systems with healthcare IoT devices to solve these security challenges. Reviewing existing literature shows the current state of IoT security and emphasizes the need for better protection. The main worry is that healthcare IoT devices can be easily hacked, putting patient data and device functionality at risk. To address this, the research suggests a detailed security framework designed for these devices. This framework, based on literature and best practices, includes important security measures like authentication, data encryption, access controls, and anomaly detection. Adding SIEM systems to this framework helps detect threats in real time and respond quickly to incidents, making healthcare IoT devices more secure. The study highlights the importance of this integration and offers guidance for implementing healthcare IoT securely, efficiently, and effectively.Keywords: cyber security, threat intelligence, forensics, heath care
Procedia PDF Downloads 687661 Combination between Intrusion Systems and Honeypots
Authors: Majed Sanan, Mohammad Rammal, Wassim Rammal
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Today, security is a major concern. Intrusion Detection, Prevention Systems and Honeypot can be used to moderate attacks. Many researchers have proposed to use many IDSs ((Intrusion Detection System) time to time. Some of these IDS’s combine their features of two or more IDSs which are called Hybrid Intrusion Detection Systems. Most of the researchers combine the features of Signature based detection methodology and Anomaly based detection methodology. For a signature based IDS, if an attacker attacks slowly and in organized way, the attack may go undetected through the IDS, as signatures include factors based on duration of the events but the actions of attacker do not match. Sometimes, for an unknown attack there is no signature updated or an attacker attack in the mean time when the database is updating. Thus, signature-based IDS fail to detect unknown attacks. Anomaly based IDS suffer from many false-positive readings. So there is a need to hybridize those IDS which can overcome the shortcomings of each other. In this paper we propose a new approach to IDS (Intrusion Detection System) which is more efficient than the traditional IDS (Intrusion Detection System). The IDS is based on Honeypot Technology and Anomaly based Detection Methodology. We have designed Architecture for the IDS in a packet tracer and then implemented it in real time. We have discussed experimental results performed: both the Honeypot and Anomaly based IDS have some shortcomings but if we hybridized these two technologies, the newly proposed Hybrid Intrusion Detection System (HIDS) is capable enough to overcome these shortcomings with much enhanced performance. In this paper, we present a modified Hybrid Intrusion Detection System (HIDS) that combines the positive features of two different detection methodologies - Honeypot methodology and anomaly based intrusion detection methodology. In the experiment, we ran both the Intrusion Detection System individually first and then together and recorded the data from time to time. From the data we can conclude that the resulting IDS are much better in detecting intrusions from the existing IDSs.Keywords: security, intrusion detection, intrusion prevention, honeypot, anomaly-based detection, signature-based detection, cloud computing, kfsensor
Procedia PDF Downloads 3857660 An Implementation of a Configurable UART-to-Ethernet Converter
Authors: Jungho Moon, Myunggon Yoon
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This paper presents an implementation of a configurable UART-to-Ethernet converter using an ARM-based 32-bit microcontroller as well as a dedicated configuration program running on a PC for configuring the operating parameters of the converter. The program was written in Python. Various parameters pertaining to the operation of the converter can be modified by the configuration program through the Ethernet interface of the converter. The converter supports 3 representative asynchronous serial communication protocols, RS-232, RS-422, and RS-485 and supports 3 network modes, TCP/IP server, TCP/IP client, and UDP client. The TCP/IP and UDP protocols were implemented on the microcontroller using an open source TCP/IP protocol stack called lwIP (A lightweight TCP/IP) and FreeRTOS, a free real-time operating system for embedded systems. Due to the use of a real-time operating system, the firmware of the converter was implemented as a multi-thread application and as a result becomes more modular and easier to develop. The converter can provide a seamless bridge between a serial port and an Ethernet port, thereby allowing existing legacy apparatuses with no Ethernet connectivity to communicate using the Ethernet protocol.Keywords: converter, embedded systems, ethernet, lwIP, UART
Procedia PDF Downloads 7097659 Human Resource Management Practices, Person-Environment Fit and Financial Performance in Brazilian Publicly Traded Companies
Authors: Bruno Henrique Rocha Fernandes, Amir Rezaee, Jucelia Appio
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The relation between Human Resource Management (HRM) practices and organizational performance remains the subject of substantial literature. Though many studies demonstrated positive relationship, still major influencing variables are not yet clear. This study considers the Person-Environment Fit (PE Fit) and its components, Person-Supervisor (PS), Person-Group (PG), Person-Organization (PO) and Person-Job (PJ) Fit, as possible explanatory variables. We analyzed PE Fit as a moderator between HRM practices and financial performance in the “best companies to work” in Brazil. Data from HRM practices were classified through the High Performance Working Systems (HPWS) construct and data on PE-Fit were obtained through surveys among employees. Financial data, consisting of return on invested capital (ROIC) and price earnings ratio (PER) were collected for publicly traded best companies to work. Findings show that PO Fit and PJ Fit play a significant moderator role for PER but not for ROIC.Keywords: financial performance, human resource management, high performance working systems, person-environment fit
Procedia PDF Downloads 1677658 Heliport Remote Safeguard System Based on Real-Time Stereovision 3D Reconstruction Algorithm
Authors: Ł. Morawiński, C. Jasiński, M. Jurkiewicz, S. Bou Habib, M. Bondyra
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With the development of optics, electronics, and computers, vision systems are increasingly used in various areas of life, science, and industry. Vision systems have a huge number of applications. They can be used in quality control, object detection, data reading, e.g., QR-code, etc. A large part of them is used for measurement purposes. Some of them make it possible to obtain a 3D reconstruction of the tested objects or measurement areas. 3D reconstruction algorithms are mostly based on creating depth maps from data that can be acquired from active or passive methods. Due to the specific appliance in airfield technology, only passive methods are applicable because of other existing systems working on the site, which can be blinded on most spectral levels. Furthermore, reconstruction is required to work long distances ranging from hundreds of meters to tens of kilometers with low loss of accuracy even with harsh conditions such as fog, rain, or snow. In response to those requirements, HRESS (Heliport REmote Safeguard System) was developed; which main part is a rotational head with a two-camera stereovision rig gathering images around the head in 360 degrees along with stereovision 3D reconstruction and point cloud combination. The sub-pixel analysis introduced in the HRESS system makes it possible to obtain an increased distance measurement resolution and accuracy of about 3% for distances over one kilometer. Ultimately, this leads to more accurate and reliable measurement data in the form of a point cloud. Moreover, the program algorithm introduces operations enabling the filtering of erroneously collected data in the point cloud. All activities from the programming, mechanical and optical side are aimed at obtaining the most accurate 3D reconstruction of the environment in the measurement area.Keywords: airfield monitoring, artificial intelligence, stereovision, 3D reconstruction
Procedia PDF Downloads 1277657 User Modeling from the Perspective of Improvement in Search Results: A Survey of the State of the Art
Authors: Samira Karimi-Mansoub, Rahem Abri
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Currently, users expect high quality and personalized information from search results. To satisfy user’s needs, personalized approaches to web search have been proposed. These approaches can provide the most appropriate answer for user’s needs by using user context and incorporating information about query provided by combining search technologies. To carry out personalized web search, there is a need to make different techniques on whole of user search process. There are the number of possible deployment of personalized approaches such as personalized web search, personalized recommendation, personalized summarization and filtering systems and etc. but the common feature of all approaches in various domains is that user modeling is utilized to provide personalized information from the Web. So the most important work in personalized approaches is user model mining. User modeling applications and technologies can be used in various domains depending on how the user collected information may be extracted. In addition to, the used techniques to create user model is also different in each of these applications. Since in the previous studies, there was not a complete survey in this field, our purpose is to present a survey on applications and techniques of user modeling from the viewpoint of improvement in search results by considering the existing literature and researches.Keywords: filtering systems, personalized web search, user modeling, user search behavior
Procedia PDF Downloads 2817656 Accounting Propositions for Sustainability Performance Information Systems Introduction: Environmental Attributes from Croatian Hotels
Authors: Vanja Vejzagic, Jackie Brander Brown, Peter Schmidt
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Purpose: For some time now, the global hotel industry trends are strongly oriented towards sustainable development and environmental management accounting (EMA) should have the supporting role for hotel’s corporate social responsibility (CSR) management. The aim of this paper is thus to analyse and present data on the key steps leading toward the effective incorporation of EMA within hotel performance information systems. Design/Methodology/Approach: The research study is a continuation of the process carried out on the sample of 20 eco-hotels in the UK, a year ago. Research evidence was obtained via in-depth case studies on sample of 180 hotels (4 and 5 stars hotels) located in Croatia. Research was conducted through interviews with key personnel and an online survey which specifically focused on 10 business areas considered vital for successful EMA integration. Findings: The research results indicate a pattern by which hotels can determine the existing level of their sustainable (environmental) business. Furthermore, the management understanding of the sustainability concept was still proven to lead to a relatively subjective appreciation and presentation of sustainable hotel operations and their performance. It was determined that majority of analysed hotel organisations reflect typical short-term, financially oriented performance information systems. Steps for EMA introduction have been offered. Research Limitations/Implications: CSR is still a broad-set concept. Exploring the effects of EMA on such-like a defined management system may be subject to considerable influence of the respondent’s subjective perception of the concept. Originality/Value: This article should be of interest to higher education academics and careers staff who have an interest in CSR introduction and the ways of implementing its informational support for performance measurement.Keywords: environmental management accounting, EMA, corporate social responsibility, CSR, sustainability, hotel
Procedia PDF Downloads 1757655 Doing Cause-and-Effect Analysis Using an Innovative Chat-Based Focus Group Method
Authors: Timothy Whitehill
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This paper presents an innovative chat-based focus group method for collecting qualitative data to construct a cause-and-effect analysis in business research. This method was developed in response to the research and data collection challenges faced by the Covid-19 outbreak in the United Kingdom during 2020-21. This paper discusses the methodological approaches and builds a contemporary argument for its effectiveness in exploring cause-and-effect relationships in the context of focus group research, systems thinking and problem structuring methods. The pilot for this method was conducted between October 2020 and March 2021 and collected more than 7,000 words of chat-based data which was used to construct a consensus drawn cause-and-effect analysis. This method was developed in support of an ongoing Doctorate in Business Administration (DBA) thesis, which is using Design Science Research methodology to operationalize organisational resilience in UK construction sector firms.Keywords: cause-and-effect analysis, focus group research, problem structuring methods, qualitative research, systems thinking
Procedia PDF Downloads 2247654 Individual Differences in Affective Neuroscience Personality Traits Predict Several Dimensions of Psychological Wellbeing. A Cross-Sectional Study in Healthy Subjects
Authors: Valentina Colonnello, Paolo Maria Russo
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Decades of cross-species affective neuroscience research by Panksepp and others have identified basic evolutionarily preserved subcortical emotional systems that humans share with mammals and many vertebrates. These primary emotional systems encode unconditional affective responses and contribute to the development of personality traits throughout ontogenesis and interactions with the environment. The Affective Neuroscience Personality Scale (ANPS) measures individual differences in affective personality traits associated with the basic emotional systems of CARE, PLAY, SEEKING, SADNESS, FEAR, and ANGER, along with Spirituality, which is a more cognitively and socially refined expression of affectivity. Though the ANPS’s power to predict human psychological distress has been documented, to the best of our knowledge, its predictive power for psychological wellbeing has not been explored. This study therefore investigates the relationship between affective neuroscience traits and psychological wellbeing facets. Because the emotional systems are thought to influence cognitively-mediated mental processes about the self and the world, understanding the relationship between affective traits and psychological wellbeing is particularly relevant to understanding the affective dimensions of health. In a cross-sectional study, healthy participants (n = 402) completed the ANPS and the Psychological Wellbeing scale. Multiple regressions revealed that each facet of wellbeing was explained by two to four affective traits, and each trait was significantly related to at least one aspect of wellbeing. Specifically, SEEKING predicted all the wellbeing facets, except for positive relations; CARE predicted personal growth, positive relations, purpose in life, and self-acceptance; PLAY and, inversely, ANGER predicted positive relations; SADNESS inversely predicted autonomy, while FEAR inversely predicted purpose in life. SADNESS and FEAR inversely predicted environmental mastery and self-acceptance. Finally, Spirituality predicted personal growth, positive relations, and self-acceptance. These findings are the first to show the relationship between affective neuroscience personality traits and psychological wellbeing. They also call attention to the distinctive role of FEAR and PANIC traits in psychological wellbeing facets, thereby complementing or even overcoming the traditional personality approach to neuroticism as a global trait.Keywords: affective neuroscience, individual differences, personality, wellbeing
Procedia PDF Downloads 1207653 Human-Machine Cooperation in Facial Comparison Based on Likelihood Scores
Authors: Lanchi Xie, Zhihui Li, Zhigang Li, Guiqiang Wang, Lei Xu, Yuwen Yan
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Image-based facial features can be classified into category recognition features and individual recognition features. Current automated face recognition systems extract a specific feature vector of different dimensions from a facial image according to their pre-trained neural network. However, to improve the efficiency of parameter calculation, an algorithm generally reduces the image details by pooling. The operation will overlook the details concerned much by forensic experts. In our experiment, we adopted a variety of face recognition algorithms based on deep learning, compared a large number of naturally collected face images with the known data of the same person's frontal ID photos. Downscaling and manual handling were performed on the testing images. The results supported that the facial recognition algorithms based on deep learning detected structural and morphological information and rarely focused on specific markers such as stains and moles. Overall performance, distribution of genuine scores and impostor scores, and likelihood ratios were tested to evaluate the accuracy of biometric systems and forensic experts. Experiments showed that the biometric systems were skilled in distinguishing category features, and forensic experts were better at discovering the individual features of human faces. In the proposed approach, a fusion was performed at the score level. At the specified false accept rate, the framework achieved a lower false reject rate. This paper contributes to improving the interpretability of the objective method of facial comparison and provides a novel method for human-machine collaboration in this field.Keywords: likelihood ratio, automated facial recognition, facial comparison, biometrics
Procedia PDF Downloads 1317652 Performance Analysis of Solar Assisted Air Condition Using Carbon Dioxide as Refrigerant
Authors: Olusola Bamisile, Ferdinard Dika, Mustafa Dagbasi, Serkan Abbasoglu
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The aim of this study was to model an air conditioning system that brings about effective cooling and reduce fossil fuel consumption with solar energy as an alternative source of energy. The objective of the study is to design a system with high COP, low usage of electricity and to integrate solar energy into AC systems. A hybrid solar assisted air conditioning system is designed to produce 30kW cooling capacity and R744 (CO₂) is used as a refrigerant. The effect of discharge pressure on the performance of the system is studied. The subcool temperature, evaporating temperature (5°C) and suction gas return temperature (12°C) are kept constant for the four different discharge pressures considered. The cooling gas temperature is set at 25°C, and the discharge pressure includes 80, 85, 90 and 95 bars. Copeland Scroll software is used for the simulation. A pressure-enthalpy graph is also used to deduce each enthalpy point while numerical methods were used in making other calculations. From the result of the study, it is observed that a higher COP is achieved with the use of solar assisted systems. As much as 46% of electricity requirements will be save using solar input at compressor stage.Keywords: air conditioning, solar energy, performance, energy saving
Procedia PDF Downloads 1487651 Liquid-Liquid Plug Flow Characteristics in Microchannel with T-Junction
Authors: Anna Yagodnitsyna, Alexander Kovalev, Artur Bilsky
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The efficiency of certain technological processes in two-phase microfluidics such as emulsion production, nanomaterial synthesis, nitration, extraction processes etc. depends on two-phase flow regimes in microchannels. For practical application in chemistry and biochemistry it is very important to predict the expected flow pattern for a large variety of fluids and channel geometries. In the case of immiscible liquids, the plug flow is a typical and optimal regime for chemical reactions and needs to be predicted by empirical data or correlations. In this work flow patterns of immiscible liquid-liquid flow in a rectangular microchannel with T-junction are investigated. Three liquid-liquid flow systems are considered, viz. kerosene – water, paraffin oil – water and castor oil – paraffin oil. Different flow patterns such as parallel flow, slug flow, plug flow, dispersed (droplet) flow, and rivulet flow are observed for different velocity ratios. New flow pattern of the parallel flow with steady wavy interface (serpentine flow) has been found. It is shown that flow pattern maps based on Weber numbers for different liquid-liquid systems do not match well. Weber number multiplied by Ohnesorge number is proposed as a parameter to generalize flow maps. Flow maps based on this parameter are superposed well for all liquid-liquid systems of this work and other experiments. Plug length and velocity are measured for the plug flow regime. When dispersed liquid wets channel walls plug length cannot be predicted by known empirical correlations. By means of particle tracking velocimetry technique instantaneous velocity fields in a plug flow regime were measured. Flow circulation inside plug was calculated using velocity data that can be useful for mass flux prediction in chemical reactions.Keywords: flow patterns, hydrodynamics, liquid-liquid flow, microchannel
Procedia PDF Downloads 3967650 Micromechanics of Stress Transfer across the Interface Fiber-Matrix Bonding
Authors: Fatiha Teklal, Bachir Kacimi, Arezki Djebbar
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The study and application of composite materials are a truly interdisciplinary endeavor that has been enriched by contributions from chemistry, physics, materials science, mechanics and manufacturing engineering. The understanding of the interface (or interphase) in composites is the central point of this interdisciplinary effort. From the early development of composite materials of various nature, the optimization of the interface has been of major importance. Even more important, the ideas linking the properties of composites to the interface structure are still emerging. In our study, we need a direct characterization of the interface; the micromechanical tests we are addressing seem to meet this objective and we chose to use two complementary tests simultaneously. The microindentation test that can be applied to real composites and the drop test, preferred to the pull-out because of the theoretical possibility of studying systems with high adhesion (which is a priori the case with our systems). These two tests are complementary because of the principle of the model specimen used for both the first "compression indentation" and the second whose fiber is subjected to tensile stress called the drop test. Comparing the results obtained by the two methods can therefore be rewarding.Keywords: Fiber, Interface, Matrix, Micromechanics, Pull-out
Procedia PDF Downloads 1207649 Effect of Arch-Wire Qualities and Bracket Design on the Force Systems during Sliding Mechanics
Authors: Davender Kumar
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Aim: It is important for the orthodontist to be familiar with the sliding resistance (SR) generated by the ligation method used during the space closure phase with sliding mechanics. To determine new, experimental non-conventional (slide) ligature demonstrates less friction in vitro when compared other ligatures on the market. Methods: Experimental in vitro were carried out to test the performance of the low-friction system with regard to assess the forces released by different bracket–ligature systems with bonded in iron plate mounted on an Instron machine. Results: The outcomes of experimental testing showed that the combination of the low-friction ligatures with the super elastic nickel-titanium and SS wires produced a significantly smaller amount of binding at the bracket/arch wire/ligature unit when compared to conventional elastomeric ligatures. Conclusion: The biomechanical consequences of the use of low-friction ligatures were shorter duration of orthodontic treatment during the levelling and aligning phase, concurrent dentoalveolar expansion of the dental arch, and the possibility of using biologically adequate orthodontic forces.Keywords: archwire, bracket, friction, ligation
Procedia PDF Downloads 3247648 3D Microscopy, Image Processing, and Analysis of Lymphangiogenesis in Biological Models
Authors: Thomas Louis, Irina Primac, Florent Morfoisse, Tania Durre, Silvia Blacher, Agnes Noel
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In vitro and in vivo lymphangiogenesis assays are essential for the identification of potential lymphangiogenic agents and the screening of pharmacological inhibitors. In the present study, we analyse three biological models: in vitro lymphatic endothelial cell spheroids, in vivo ear sponge assay, and in vivo lymph node colonisation by tumour cells. These assays provide suitable 3D models to test pro- and anti-lymphangiogenic factors or drugs. 3D images were acquired by confocal laser scanning and light sheet fluorescence microscopy. Virtual scan microscopy followed by 3D reconstruction by image aligning methods was also used to obtain 3D images of whole large sponge and ganglion samples. 3D reconstruction, image segmentation, skeletonisation, and other image processing algorithms are described. Fixed and time-lapse imaging techniques are used to analyse lymphatic endothelial cell spheroids behaviour. The study of cell spatial distribution in spheroid models enables to detect interactions between cells and to identify invasion hierarchy and guidance patterns. Global measurements such as volume, length, and density of lymphatic vessels are measured in both in vivo models. Branching density and tortuosity evaluation are also proposed to determine structure complexity. Those properties combined with vessel spatial distribution are evaluated in order to determine lymphangiogenesis extent. Lymphatic endothelial cell invasion and lymphangiogenesis were evaluated under various experimental conditions. The comparison of these conditions enables to identify lymphangiogenic agents and to better comprehend their roles in the lymphangiogenesis process. The proposed methodology is validated by its application on the three presented models.Keywords: 3D image segmentation, 3D image skeletonisation, cell invasion, confocal microscopy, ear sponges, light sheet microscopy, lymph nodes, lymphangiogenesis, spheroids
Procedia PDF Downloads 3817647 An Integrated Web-Based Workflow System for Design of Computational Pipelines in the Cloud
Authors: Shuen-Tai Wang, Yu-Ching Lin
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With more and more workflow systems adopting cloud as their execution environment, it presents various challenges that need to be addressed in order to be utilized efficiently. This paper introduces a method for resource provisioning based on our previous research of dynamic allocation and its pipeline processes. We present an abstraction for workload scheduling in which independent tasks get scheduled among various available processors of distributed computing for optimization. We also propose an integrated web-based workflow designer by taking advantage of the HTML5 technology and chaining together multiple tools. In order to make the combination of multiple pipelines executing on the cloud in parallel, we develop a script translator and an execution engine for workflow management in the cloud. All information is known in advance by the workflow engine and tasks are allocated according to the prior knowledge in the repository. This proposed effort has the potential to provide support for process definition, workflow enactment and monitoring of workflow processes. Users would benefit from the web-based system that allows creation and execution of pipelines without scripting knowledge.Keywords: workflow systems, resources provisioning, workload scheduling, web-based, workflow engine
Procedia PDF Downloads 1617646 Piezoelectric Actuator for Controlling Robotics Organs
Authors: Lemoussi Somia, Ouali Mohammed, Zemirline Adel
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In precision engineering, including precision positioning, micro-manipulation, robotic systems... a majority of these applications actuated by piezo stack used the compliant amplifier mechanism to amplifying motion and guiding it as needed utilize the flexibility of their components, in this paper, we present a novel approach introducing a symmetric structure comprising three stages, featuring rectangular flexure hinges with a compact size of 77mm×42mm×10mm. This design provides the capability for rotation, translation or a combination of both movements in both directions. The system allows for a displacement of 2107.5 μm when the input displacement of PZT is 50 μm while considering the material constraints of the aluminum alloy (7075 T6) which has a maximum admissible stress of 500 MPa However, our proposed design imposes additional constraints to ensure the stress remains below 361 MPa for optimal performance. These findings were obtained through finite element simulations conducted using ANSYS Workbench. Furthermore, our module facilitates precise control of various components within robotic systems, allowing for adjustable speeds based on specific requirements or desired outcomes.Keywords: robotic, piezoelectric, compliant mechanism, flexure hinge
Procedia PDF Downloads 817645 Impacts of Tillage on Biodiversity of Microarthropod Communities in Two Different Crop Systems
Authors: Leila Ramezani, Mohammad Saeid Mossadegh
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Different uses of land by humans alter the physico chemical characteristics of the soil and affect the soil microhabitat. The objective of this study was to evaluate the influence of tillage in three different human land uses on microarthropods biodiversity in Khuzestan province, southwest of Iran. Three microhabitats including a permanent grassland with old Date-Palms around and no till system, and two wheat fields, one with conservative agricultural practices and low till system and the other with conventional agricultural practices (deep tillage), were compared for the biodiversity of the two main groups of soil microarthropods (Oribatida and Collembola). Soil samples were collected from the top to a depth of 15 cm bimonthly during a period of two years. Significant differences in the biodiversity index of microarthropods were observed between the different tillage systems (F = 36.748, P =0.000). Indeed, analysis of species diversity showed that the diversity index at the conservative field with low till (2.58 ± 0.01) was higher (p < 0.05) than the conventional tilled field (2.45 ± 0.08) and the diversity of natural grassland was the highest (2.79 ± 0.19, p < 0.05). Indeed, the index of biodiversity and population abundance differed significantly in different seasons (p < 0.00).Keywords: biodiversity, Collembola, microarthropods, Oribatida
Procedia PDF Downloads 1767644 Development of the Ontology of Engineering Design Complexity
Authors: Victor E. Lopez, L. Dale Thomas
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As engineered systems become more complex, the difficulty associated with predicting, developing, and operating engineered systems also increases, resulting in increased costs, failure rates, and unexpected consequences. Successfully managing the complexity of the system should reduce these negative consequences. The study of complexity in the context of engineering development has suffered due to the ambiguity of the nature of complexity, what makes a system complex and how complexity translates to real world engineering attributes and consequences. This paper argues that the use of an ontology of engineering design complexity would i) improve the clarity of the research being performed by allowing researchers to use a common conceptualization of complexity, with more precise terminology, and ii) elucidate the connections between certain types of complexity and their consequences for system development. The ontology comprises concepts of complexity found in the literature and the different relations that exists between them. The ontology maps different complexity concepts such as structural complexity, creation complexity, and information entropy, and then relates the to system aspects such as interfaces, development effort, and modularity. The ontology is represented using the Web Ontology Language (OWL). This paper presents the current status of the ontology of engineering design complexity, the main challenges encountered, and the future plans for the ontology.Keywords: design complexity, ontology, design effort, complexity ontology
Procedia PDF Downloads 1897643 Geographic Information Systems as a Tool to Support the Sustainable Development Goals
Authors: Gulnara N. Nabiyeva, Stephen M. Wheeler
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Geographic Information Systems (GIS) is a multipurpose computer-based tool that provides a sophisticated ability to map and analyze data on different spatial layers. However, GIS is far more easily applied in some policy areas than others. This paper seeks to determine the areas of sustainable development, including environmental, economic, and social dimensions, where GIS has been used to date to support efforts to implement the United Nations Sustainable Development Goals (SDGs), and to discuss potential areas where it might be used more. Based on an extensive analysis of published literature, we ranked the SDGs according to how frequently GIS has been used to study related policy. We found that SDG#15 “Life on Land” is most often addressed with GIS, following by SDG#11 “Sustainable Cities and Communities”, and SDG#13 “Climate Action”. On the other hand, we determined that SDG#2 “Zero Hunger”, SDG#8 “Decent Work and Economic Growth”, and SDG#16 “Peace, Justice, and Strong Institutions” are least addressed with GIS. The paper outlines some specific ways that GIS might be applied to the SDGs least linked to this tool currently.Keywords: GIS, GIS application, sustainable community development, sustainable development goals
Procedia PDF Downloads 1357642 A Critical Evaluation of Occupational Safety and Health Management Systems' Implementation: Case of Mutare Urban Timber Processing Factories, Zimbabwe
Authors: Johanes Mandowa
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The study evaluated the status of Occupational Safety and Health Management Systems’ (OSHMSs) implementation by Mutare urban timber processing factories. A descriptive cross sectional survey method was utilized in the study. Questionnaires, interviews and direct observations were the techniques employed to extract primary data from the respondents. Secondary data was acquired from OSH encyclopedia, OSH journals, newspaper articles, internet, past research papers, African Newsletter on OSH and NSSA On-guard magazines among others. Analysis of data collected was conducted using statistical and descriptive methods. Results revealed an unpleasant low uptake rate (16%) of OSH Management Systems by Mutare urban timber processing factories. On a comparative basis, low implementation levels were more pronounced in small timber processing factories than in large factories. The low uptake rate of OSH Management Systems revealed by the study validates the Government of Zimbabwe and its social partners’ observation that the dismal Zimbabwe OSH performance was largely due to non implementation of safety systems at most workplaces. The results exhibited a relationship between availability of a SHE practitioner in Mutare urban timber processing factories and OSHMS implementation. All respondents and interviewees’ agreed that OSH Management Systems are handy in curbing occupational injuries and diseases. It emerged from the study that the top barriers to implementation of safety systems are lack of adequate financial resources, lack of top management commitment and lack of OSHMS implementation expertise. Key motivators for OSHMSs establishment were cited as provision of adequate resources (76%), strong employee involvement (64%) and strong senior management commitment and involvement (60%). Study results demonstrated that both OSHMSs implementation barriers and motivators affect all Mutare urban timber processing factories irrespective of size. The study recommends enactment of a law by Ministry of Public Service, Labour and Social Welfare in consultation with NSSA to make availability of an OSHMS and qualified SHE practitioner mandatory at every workplace. More so, the enacted law should prescribe minimum educational qualification required for one to practice as a SHE practitioner. Ministry of Public Service, Labour and Social Welfare and NSSA should also devise incentives such as reduced WCIF premiums for good OSH performance to cushion Mutare urban timber processing factories from OSHMS implementation costs. The study recommends the incorporation of an OSH module in the academic curriculums of all programmes offered at tertiary institutions so as to ensure that graduates who later end up assuming influential management positions in Mutare urban timber processing factories are abreast with the necessity of OSHMSs in preventing occupational injuries and diseases. In the quest to further boost management’s awareness on the importance of OSHMSs, NSSA and SAZ are urged by the study to conduct OSHMSs awareness breakfast meetings targeting executive management on a periodic basis. The Government of Zimbabwe through the Ministry of Public Service, Labour and Social Welfare should also engage ILO Country Office for Zimbabwe to solicit for ILO’s technical assistance so as to enhance the effectiveness of NSSA’s and SAZ’s OSHMSs promotional programmes.Keywords: occupational safety health management system, national social security authority, standard association of Zimbabwe, Mutare urban timber processing factories, ministry of public service, labour and social welfare
Procedia PDF Downloads 3407641 Exergy Analysis of a Vapor Absorption Refrigeration System Using Carbon Dioxide as Refrigerant
Authors: Samsher Gautam, Apoorva Roy, Bhuvan Aggarwal
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Vapor absorption refrigeration systems can replace vapor compression systems in many applications as they can operate on a low-grade heat source and are environment-friendly. Widely used refrigerants such as CFCs and HFCs cause significant global warming. Natural refrigerants can be an alternative to them, among which carbon dioxide is promising for use in automotive air conditioning systems. Its inherent safety, ability to withstand high pressure and high heat transfer coefficient coupled with easy availability make it a likely choice for refrigerant. Various properties of the ionic liquid [bmim][PF₆], such as non-toxicity, stability over a wide temperature range and ability to dissolve gases like carbon dioxide, make it a suitable absorbent for a vapor absorption refrigeration system. In this paper, an absorption chiller consisting of a generator, condenser, evaporator and absorber was studied at an operating temperature of 70⁰C. A thermodynamic model was set up using the Peng-Robinson equations of state to predict the behavior of the refrigerant and absorbent pair at different points in the system. A MATLAB code was used to obtain the values of enthalpy and entropy at selected points in the system. The exergy destruction in each component and exergetic coefficient of performance (ECOP) of the system were calculated by performing an exergy analysis based on the second law of thermodynamics. Graphs were plotted between varying operating conditions and the ECOP obtained in each case. The effect of every component on the ECOP was examined. The exergetic coefficient of performance was found to be lesser than the coefficient of performance based on the first law of thermodynamics.Keywords: [bmim][PF₆] as absorbent, carbon dioxide as refrigerant, exergy analysis, Peng-Robinson equations of state, vapor absorption refrigeration
Procedia PDF Downloads 2897640 Evaluation and Analysis of ZigBee-Based Wireless Sensor Network: Home Monitoring as Case Study
Authors: Omojokun G. Aju, Adedayo O. Sule
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ZigBee wireless sensor and control network is one of the most popularly deployed wireless technologies in recent years. This is because ZigBee is an open standard lightweight, low-cost, low-speed, low-power protocol that allows true operability between systems. It is built on existing IEEE 802.15.4 protocol and therefore combines the IEEE 802.15.4 features and newly added features to meet required functionalities thereby finding applications in wide variety of wireless networked systems. ZigBee‘s current focus is on embedded applications of general-purpose, inexpensive, self-organising networks which requires low to medium data rates, high number of nodes and very low power consumption such as home/industrial automation, embedded sensing, medical data collection, smart lighting, safety and security sensor networks, and monitoring systems. Although the ZigBee design specification includes security features to protect data communication confidentiality and integrity, however, when simplicity and low-cost are the goals, security is normally traded-off. A lot of researches have been carried out on ZigBee technology in which emphasis has mainly been placed on ZigBee network performance characteristics such as energy efficiency, throughput, robustness, packet delay and delivery ratio in different scenarios and applications. This paper investigate and analyse the data accuracy, network implementation difficulties and security challenges of ZigBee network applications in star-based and mesh-based topologies with emphases on its home monitoring application using the ZigBee ProBee ZE-10 development boards for the network setup. The paper also expose some factors that need to be considered when designing ZigBee network applications and suggest ways in which ZigBee network can be designed to provide more resilient to network attacks.Keywords: home monitoring, IEEE 802.14.5, topology, wireless security, wireless sensor network (WSN), ZigBee
Procedia PDF Downloads 3857639 Development of Pothole Management Method Using Automated Equipment with Multi-Beam Sensor
Authors: Sungho Kim, Jaechoul Shin, Yujin Baek, Nakseok Kim, Kyungnam Kim, Shinhaeng Jo
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The climate change and increase in heavy traffic have been accelerating damages that cause the problems such as pothole on asphalt pavement. Pothole causes traffic accidents, vehicle damages, road casualties and traffic congestion. A quick and efficient maintenance method is needed because pothole is caused by stripping and accelerates pavement distress. In this study, we propose a rapid and systematic pothole management by developing a pothole automated repairing equipment including a volume measurement system of pothole. Three kinds of cold mix asphalt mixture were investigated to select repair materials. The materials were evaluated for satisfaction with quality standard and applicability to automated equipment. The volume measurement system of potholes was composed of multi-sensor that are combined with laser sensor and ultrasonic sensor and installed in front and side of the automated repair equipment. An algorithm was proposed to calculate the amount of repair material according to the measured pothole volume, and the system for releasing the correct amount of material was developed. Field test results showed that the loss of repair material amount could be reduced from approximately 20% to 6% per one point of pothole. Pothole rapid automated repair equipment will contribute to improvement on quality and efficient and economical maintenance by not only reducing materials and resources but also calculating appropriate materials. Through field application, it is possible to improve the accuracy of pothole volume measurement, to correct the calculation of material amount, and to manage the pothole data of roads, thereby enabling more efficient pavement maintenance management. Acknowledgment: The author would like to thank the MOLIT(Ministry of Land, Infrastructure, and Transport). This work was carried out through the project funded by the MOLIT. The project name is 'development of 20mm grade for road surface detecting roadway condition and rapid detection automation system for removal of pothole'.Keywords: automated equipment, management, multi-beam sensor, pothole
Procedia PDF Downloads 2247638 Pulsatile Drug Delivery System for Chronopharmacological Disorders
Authors: S. S. Patil, B. U. Janugade, S. V. Patil
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Pulsatile systems are gaining a lot of interest as they deliver the drug at the right site of action at the right time and in the right amount, thus providing spatial and temporal delivery thus increasing patient compliance. These systems are designed according to the circadian rhythm of the body. Chronotherapeutics is the discipline concerned with the delivery of drugs according to inherent activities of a disease over a certain period of time. It is becoming increasingly more evident that the specific time that patients take their medication may be even more significant than was recognized in the past. The tradition of prescribing medication at evenly spaced time intervals throughout the day, in an attempt to maintain constant drug levels throughout a 24-hour period, may be changing as researcher’s report that some medications may work better if their administration is coordinated with day-night patterns and biological rhythms. The potential benefits of chronotherapeutics have been demonstrated in the management of a number of diseases. In particular, there is a great deal of interest in how chronotherapy can particularly benefit patients suffering from allergic rhinitis, rheumatoid arthritis and related disorders, asthma, cancer, cardiovascular diseases, and peptic ulcer disease.Keywords: pulsatile drug delivery, chronotherapeutics, circadian rhythm, asthma, chronobiology
Procedia PDF Downloads 366