Search results for: leisure time activity
17616 Mobility and Effective Regulatory Policies in the 21st Century Transport Sector
Authors: Pedro Paulino
Abstract:
The majority of the world’s population is already living in urban areas and the urban population is expected to keep increasing in the next decades. This exponential increase in urban population carries with it obvious mobility problems. Not only a new paradigm in the transport sector is needed in order to address these problems; effective regulatory policies to ensure the quality of services, passenger rights, competition between operators and consistency of the entire mobile ecosystem are needed as well. The purpose of this paper is to present the problems the world faces in this sector and contribute to their solution. Indeed, our study concludes that only through the active supervision of the markets and the activity of monitoring the various operators will it be possible to develop a sustainable and efficient transport system which meets the needs of a changing world.Keywords: mobility, regulation policies, sanctioning powers, sustainable transport
Procedia PDF Downloads 30017615 Ultra-Wideband Antennas for Ultra-Wideband Communication and Sensing Systems
Authors: Meng Miao, Jeongwoo Han, Cam Nguyen
Abstract:
Ultra-wideband (UWB) time-domain impulse communication and radar systems use ultra-short duration pulses in the sub-nanosecond regime, instead of continuous sinusoidal waves, to transmit information. The pulse directly generates a very wide-band instantaneous signal with various duty cycles depending on specific usages. In UWB systems, the total transmitted power is spread over an extremely wide range of frequencies; the power spectral density is extremely low. This effectively results in extremely small interference to other radio signals while maintains excellent immunity to interference from these signals. UWB devices can therefore work within frequencies already allocated for other radio services, thus helping to maximize this dwindling resource. Therefore, impulse UWB technique is attractive for realizing high-data-rate, short-range communications, ground penetrating radar (GPR), and military radar with relatively low emission power levels. UWB antennas are the key element dictating the transmitted and received pulse shape and amplitude in both time and frequency domain. They should have good impulse response with minimal distortion. To facilitate integration with transmitters and receivers employing microwave integrated circuits, UWB antennas enabling direct integration are preferred. We present the development of two UWB antennas operating from 3.1 to 10.6 GHz and 0.3-6 GHz for UWB systems that provide direct integration with microwave integrated circuits. The operation of these antennas is based on the principle of wave propagation on a non-uniform transmission line. Time-domain EM simulation is conducted to optimize the antenna structures to minimize reflections occurring at the open-end transition. Calculated and measured results of these UWB antennas are presented in both frequency and time domains. The antennas have good time-domain responses. They can transmit and receive pulses effectively with minimum distortion, little ringing, and small reflection, clearly demonstrating the signal fidelity of the antennas in reproducing the waveform of UWB signals which is critical for UWB sensors and communication systems. Good performance together with seamless microwave integrated-circuit integration makes these antennas good candidates not only for UWB applications but also for integration with printed-circuit UWB transmitters and receivers.Keywords: antennas, ultra-wideband, UWB, UWB communication systems, UWB radar systems
Procedia PDF Downloads 23817614 Oxidative Damage to Lipids, Proteins, and DNA during Differentiation of Mesenchymal Stem Cells Derived from Umbilical Cord into Biologically Active Hepatocytes
Authors: Abdolamir Allameh, Shahnaz Esmaeili, Mina Allameh, Safoura Khajeniazi
Abstract:
Stem cells with therapeutic applications can be isolated from human placenta/umblical cord blood (UCB) as well as the cord tissue (UC). Stem cells in culture are vulnerable to oxidative stress, particularly when subjected to differentiation process. The aim of this study was to examine the chnages in the rate of oxidation that occurs to cellular macromolecules during hepatic differentiation of mononuclear cells (MSCs). In addition, the impact of the hepatic differentiation process of MSC on cellular and biological activity of the cells will be undertaken. For this purpose, first mononuclear cells (MNCs) were isolated from human UCB which was obtained from a healthy full-term infant. The cells were cultured at a density of 3×10⁵ cells/cm² in DMEM- low-glucose culture media supplemented with 20% FBS, 2 mM L-glutamine, 100 μg/ml streptomycin and 100 U/ml penicillin. Cell cultures were then incubated at 37°C in a humidified 5% CO₂ incubator. After removing non-adherent cells by replacing culture medium, fibroblast-like adherent cells were resuspended in 0.25% trypsin-EDTA and plated in 25 cm² flasks (1×10⁴/ml). Characterization of the MSCs was routinely done by observing their morphology and growth curve. MSCs were subjected to a 2-step hepatocyte differentiation protocol in presence of hepatocyte growth factor (HGF), dexamethazone (DEX) and oncostatin M (OSM). The hepatocyte-like cells derived from MSCs were checked every week for 3 weeks for changes in lipid peroxidation, protein carbonyl formation and DNA oxidation i.e., 8-hydroxy-2'-deoxyguanosine (8-OH-dG) assay. During the 3-week differentiation process of MSCs to hepatocyte-like cells we found that expression liver-specific markers such as albumin, was associated with increased levels of lipid peroxidation and protein carbonyl formation. Whereas, undifferentiated MSCs has relatively low levels of lipid peroxidation products. There was a significant increase ( p < 0.05) in lipid peroxidation products in hepatocytes on days 7, 14, and 21 of differentiation. Likewise, the level of protein carbonyls in the cells was elevated during the differentiation. The level of protein carbonyls measured in hepatocyte-like cells obtained 3 weeks after differentiation induction was estimated to be ~6 fold higher compared to cells recovered on day 7 of differentiation. On the contrary, there was a small but significant decrease in DNA damage marker (8-OH-dG) in hepatocytes recovered 3 weeks after differentiation onset. The level of 8-OHdG which was in consistent with formation of reactive oxygen species (ROS). In conclusion, this data suggest that despite the elevation in oxidation of lipid and protein molecules during hepatocyte development, the cells were normal in terms of DNA integrity, morphology, and biologically activity.Keywords: adult stem cells, DNA integrity, free radicals, hepatic differentiation
Procedia PDF Downloads 15017613 Automatic Seizure Detection Using Weighted Permutation Entropy and Support Vector Machine
Authors: Noha Seddik, Sherine Youssef, Mohamed Kholeif
Abstract:
The automated epileptic seizure detection research field has emerged in the recent years; this involves analyzing the Electroencephalogram (EEG) signals instead of the traditional visual inspection performed by expert neurologists. In this study, a Support Vector Machine (SVM) that uses Weighted Permutation Entropy (WPE) as the input feature is proposed for classifying normal and seizure EEG records. WPE is a modified statistical parameter of the permutation entropy (PE) that measures the complexity and irregularity of a time series. It incorporates both the mapped ordinal pattern of the time series and the information contained in the amplitude of its sample points. The proposed system utilizes the fact that entropy based measures for the EEG segments during epileptic seizure are lower than in normal EEG.Keywords: electroencephalogram (EEG), epileptic seizure detection, weighted permutation entropy (WPE), support vector machine (SVM)
Procedia PDF Downloads 37217612 Investigation of Astrocyte Physiology on Stiffness-Controlled Cellulose Acetate Nanofiber as a Tissue Scaffold
Authors: Sun Il Yu, Jung Hyun Joo, Hwa Sung Shin
Abstract:
Astrocytes are known as dominant cells in CNS and play a role as a supporter of CNS activity and regeneration. Recently, three-dimensional culture of astrocytes were actively applied to understand in vivo astrocyte works. Electrospun nanofibers are attractive for 3D cell culture system because they have a high surface to volume ratio and porous structure, and have already been used for 3D astrocyte cultures. In this research, the stiffness of cellulose acetate (CA) nanofiber was controlled by heat treatment. As stiffness increased, astrocyte cell viability and adhesion increased. Reactivity of astrocyte was also upregulated in stiffer CA nanofiber in terms of GFAP, an intermediate filament protein. Finally, we demonstrated that stiffness-controllable CA is attractive for astrocyte tissue engineering.Keywords: astrocyte, cellulose acetate, nanofiber, tissue scaffold
Procedia PDF Downloads 35517611 Time Efficient Color Coding for Structured-Light 3D Scanner
Authors: Po-Hao Huang, Pei-Ju Chiang
Abstract:
The structured light 3D scanner is commonly used for measuring the 3D shape of an object. Through projecting designed light patterns on the object, deformed patterns can be obtained and used for the geometric shape reconstruction. At present, Gray code is the most reliable and commonly used light pattern in the structured light 3D scanner. However, the trade-off between scanning efficiency and accuracy is a long-standing and challenging problem. The design of light patterns plays a significant role in the scanning efficiency and accuracy. Thereby, we proposed a novel encoding method integrating color information and Gray-code to improve the scanning efficiency. We will demonstrate that with the proposed method, the scanning time can be reduced to approximate half of the one needed by Gray-code without reduction of precision.Keywords: gray-code, structured light scanner, 3D shape acquisition, 3D reconstruction
Procedia PDF Downloads 45817610 Epoxomicin Affects Proliferating Neural Progenitor Cells of Rat
Authors: Bahaa Eldin A. Fouda, Khaled N. Yossef, Mohamed Elhosseny, Ahmed Lotfy, Mohamed Salama, Mohamed Sobh
Abstract:
Developmental neurotoxicity (DNT) entails the toxic effects imparted by various chemicals on the brain during the early childhood period. As human brains are vulnerable during this period, various chemicals would have their maximum effects on brains during early childhood. Some toxicants have been confirmed to induce developmental toxic effects on CNS e.g. lead, however; most of the agents cannot be identified with certainty due the defective nature of predictive toxicology models used. A novel alternative method that can overcome most of the limitations of conventional techniques is the use of 3D neurospheres system. This in-vitro system can recapitulate most of the changes during the period of brain development making it an ideal model for predicting neurotoxic effects. In the present study, we verified the possible DNT of epoxomicin which is a naturally occurring selective proteasome inhibitor with anti-inflammatory activity. Rat neural progenitor cells were isolated from rat embryos (E14) extracted from placental tissue. The cortices were aseptically dissected out from the brains of the fetuses and the tissues were triturated by repeated passage through a fire-polished constricted Pasteur pipette. The dispersed tissues were allowed to settle for 3 min. The supernatant was, then, transferred to a fresh tube and centrifuged at 1,000 g for 5 min. The pellet was placed in Hank’s balanced salt solution cultured as free-floating neurospheres in proliferation medium. Two doses of epoxomicin (1µM and 10µM) were used in cultured neuropsheres for a period of 14 days. For proliferation analysis, spheres were cultured in proliferation medium. After 0, 4, 5, 11, and 14 days, sphere size was determined by software analyses. The diameter of each neurosphere was measured and exported to excel file further to statistical analysis. For viability analysis, trypsin-EDTA solution were added to neurospheres for 3 min to dissociate them into single cells suspension, then viability evaluated by the Trypan Blue exclusion test. Epoxomicin was found to affect proliferation and viability of neuropsheres, these effects were positively correlated to doses and progress of time. This study confirms the DNT effects of epoxomicin on 3D neurospheres model. The effects on proliferation suggest possible gross morphologic changes while the decrease in viability propose possible focal lesion on exposure to epoxomicin during early childhood.Keywords: neural progentor cells, epoxomicin, neurosphere, medical and health sciences
Procedia PDF Downloads 42717609 Managing High-Performance Virtual Teams
Authors: Mehdi Rezai, Asghar Zamani
Abstract:
Virtual teams are a reality in today’s fast-paced world. With the possibility of commonly using common resources, an increase of inter-organizational projects, cooperation, outsourcing, and the increase in the number of people who work remotely or flexitime, an extensive and active presence of high-performance teams is a must. Virtual teams are a challenge by themselves. Their members remove the barriers of cultures, time regions and organizations, and they often communicate through electronic devices over considerable distances. Firstly, we examine the management of virtual teams by considering different issues such as cultural and personal diversities, communications and arrangement issues. Then we will examine individuals, processes and the existing tools in a team. The main challenge is managing high-performance virtual teams. First of all, we must examine the concept of performance. Then, we must focus on teams and the best methods of managing them. Constant improvement of performance, together with precisely regulating every individual’s method of working, increases the levels of performance in the course of time. High-performance teams exploit every issue as an opportunity for achieving high performance. And we know that doing projects with high performance is among every organization or team’s objectives. Performance could be measured using many criteria, among which carrying out projects in time, the satisfaction of stakeholders, and not exceeding budgets could be named. Elements such as clear objectives, clearly-defined roles and responsibilities, effective communications, and commitment to collaboration are essential to a team’s effectiveness. Finally, we will examine roles, systems, processes and will carry out a cause-and-effect analysis of different criteria in improving a team’s performance.Keywords: virtual teams, performance, management, process, improvement, effectiveness
Procedia PDF Downloads 14817608 Pentax Airway Scope Video Laryngoscope for Orotracheal Intubation in Children: A Randomized Controlled Trial
Authors: In Kyong Yi, Yun Jeong Chae, Jihoon Hwang, Sook-Young Lee, Jong-Yeop Kim
Abstract:
Background: Pentax airway scope (AWS) is a recently developed video laryngoscope for use in both normal and difficult airways, providing a good laryngeal view. The purpose of this randomized noninferior study was to evaluate the efficacy of the Pentax-AWS regarding intubation time, laryngeal view and ease of intubation in pediatric patients with normal airway, compared to Macintosh laryngoscope. Method: A total of 136 pediatric patients aged 1 to 10 with American Society of Anesthesiologists physical status I or II undergoing general anesthesia required orotracheal intubation were randomly allocated into two groups: Macintosh laryngoscope (n =68) and Pentax AWS (n=68). Anesthesia was induced with propofol, rocuronium, and sevoflurane. The primary outcome was intubation time. Cormack-Lehane laryngeal view grade, application of optimal laryngeal external manipulation (OELM), intubation difficulty scale (IDS), intubation failure rate and adverse events were also measured. Result: No significant difference was observed between the two groups regarding intubation time (Macintosh; 23[22-26] sec vs. Pentax; 23.5[22-27.75] sec, p=0.713). As for the laryngeal view grade, the Pentax group showed less number of grade 2a or higher grade cases compared to the Macintosh group (1/2a/2b/3; 52.9%/41.2%/4.4%/1.5% vs. 98.5%/1.5%/0%/0%, p=0.000). No optimal laryngeal external manipulation application was required in the Pentax group (38.2% vs. 0%, p=0.000). Intubation difficulty scale resulted in lower values for Pentax group (0 [0-2] vs. 0 [0-0.55], p=0.001). Failure rate was not different between the two groups (1.5% vs. 4.4%, p=0.619). Adverse event-wise, slightly higher incidence of bleeding (1.5% vs. 5.9%, p=0.172) and teeth injury (0% vs. 5.9%, p=0.042) occurred in the Pentax group. Conclusion: In conclusion, Pentax-AWS provided better laryngeal view, similar intubation time and similar success rate compared with Macintosh laryngoscope in children with normal airway. However, the risk of teeth injury might increase and warrant special attention.Keywords: Pentax-AWS, pediatric, video laryngoscope, intubation
Procedia PDF Downloads 20217607 A Laser Instrument Rapid-E+ for Real-Time Measurements of Airborne Bioaerosols Such as Bacteria, Fungi, and Pollen
Authors: Minghui Zhang, Sirine Fkaier, Sabri Fernana, Svetlana Kiseleva, Denis Kiselev
Abstract:
The real-time identification of bacteria and fungi is difficult because they emit much weaker signals than pollen. In 2020, Plair developed Rapid-E+, which extends abilities of Rapid-E to detect smaller bioaerosols such as bacteria and fungal spores with diameters down to 0.3 µm, while keeping the similar or even better capability for measurements of large bioaerosols like pollen. Rapid-E+ enables simultaneous measurements of (1) time-resolved, polarization and angle dependent Mie scattering patterns, (2) fluorescence spectra resolved in 16 channels, and (3) fluorescence lifetime of individual particles. Moreover, (4) it provides 2D Mie scattering images which give the full information on particle morphology. The parameters of every single bioaerosol aspired into the instrument are subsequently analysed by machine learning. Firstly, pure species of microbes, e.g., Bacillus subtilis (a species of bacteria), and Penicillium chrysogenum (a species of fungal spores), were aerosolized in a bioaerosol chamber for Rapid-E+ training. Afterwards, we tested microbes under different concentrations. We used several steps of data analysis to classify and identify microbes. All single particles were analysed by the parameters of light scattering and fluorescence in the following steps. (1) They were treated with a smart filter block to get rid of non-microbes. (2) By classification algorithm, we verified the filtered particles were microbes based on the calibration data. (3) The probability threshold (defined by the user) step provides the probability of being microbes ranging from 0 to 100%. We demonstrate how Rapid-E+ identified simultaneously microbes based on the results of Bacillus subtilis (bacteria) and Penicillium chrysogenum (fungal spores). By using machine learning, Rapid-E+ achieved identification precision of 99% against the background. The further classification suggests the precision of 87% and 89% for Bacillus subtilis and Penicillium chrysogenum, respectively. The developed algorithm was subsequently used to evaluate the performance of microbe classification and quantification in real-time. The bacteria and fungi were aerosolized again in the chamber with different concentrations. Rapid-E+ can classify different types of microbes and then quantify them in real-time. Rapid-E+ enables classifying different types of microbes and quantifying them in real-time. Rapid-E+ can identify pollen down to species with similar or even better performance than the previous version (Rapid-E). Therefore, Rapid-E+ is an all-in-one instrument which classifies and quantifies not only pollen, but also bacteria and fungi. Based on the machine learning platform, the user can further develop proprietary algorithms for specific microbes (e.g., virus aerosols) and other aerosols (e.g., combustion-related particles that contain polycyclic aromatic hydrocarbons).Keywords: bioaerosols, laser-induced fluorescence, Mie-scattering, microorganisms
Procedia PDF Downloads 9117606 Banking Crisis and Economic Effects of the Banking Crisis in Turkey
Authors: Sevilay Konya, Sadife Güngör, Zeynep Karaçor
Abstract:
Turkish economy is occurred depending on different factors from time to time and the banking crises of different magnitudes. Foremost among the factors which hinder the development of countries and societies- crises in the country's economy. Countries' economic growth rates affect inflation, unemployment and external trade. In this study, effect of November 2000, February 2001 and 2008 banking crisis on Turkey's economy and banking crisis will be examined and announced as conceptual. In this context, this study is investigates Turkey's GDP, inflation, unemployment and foreign trade figures. Turkey's economy affected have been identified from 2000 November 2001 February and 2008 banking crisis.Keywords: banking crises, Turkey’s economy, economic effects, Turkey
Procedia PDF Downloads 29517605 Cooperative Coevolution for Neuro-Evolution of Feed Forward Networks for Time Series Prediction Using Hidden Neuron Connections
Authors: Ravneil Nand
Abstract:
Cooperative coevolution uses problem decomposition methods to solve a larger problem. The problem decomposition deals with breaking down the larger problem into a number of smaller sub-problems depending on their method. Different problem decomposition methods have their own strengths and limitations depending on the neural network used and application problem. In this paper we are introducing a new problem decomposition method known as Hidden-Neuron Level Decomposition (HNL). The HNL method is competing with established problem decomposition method in time series prediction. The results show that the proposed approach has improved the results in some benchmark data sets when compared to the standalone method and has competitive results when compared to methods from literature.Keywords: cooperative coevaluation, feed forward network, problem decomposition, neuron, synapse
Procedia PDF Downloads 33617604 Control of Hybrid System Using Fuzzy Logic
Authors: Faiza Mahi, Fatima Debbat, Mohamed Fayçal Khelfi
Abstract:
This paper proposes a control approach using Fuzzy Lo system. More precisely, the study focuses on the improvement of users service in terms of analysis and control of a transportation system their waiting times in the exchange platforms of passengers. Many studies have been developed in the literature for such problematic, and many control tools are proposed. In this paper we focus on the use of fuzzy logic technique to control the system during its evolution in order to minimize the arrival gap of connected transportation means at the exchange points of passengers. An example of illustration is worked out and the obtained results are reported. an important area of research is the modeling and simulation ordering system. We describe an approach to analysis using Fuzzy Logic. The hybrid simulator developed in toolbox Matlab consists calculation of waiting time transportation mode.Keywords: Fuzzy logic, Hybrid system, Waiting Time, Transportation system, Control
Procedia PDF Downloads 55517603 Aloe vera Prevents Injuries Induced by Whole Body X-ray Irradiation in Rodents
Authors: Shashi Bala, Neha A. Chugh, Subhash C. Bansal, Mohal L. Garg, Ashwani Koul
Abstract:
Purpose: The present study was designed to evaluate the radioprotective efficacy of Aloe vera from whole body X-ray exposure in rodents. Materials and Methods: For this purpose, after on week’s acclimatization, male balb/c mice procured from Central Animal House, Panjab University, Chandigarh (India), were divided into four groups: Group I mice served as control. Group II mice were orally administrated Aloe vera pulp extract (50 mg/ kg body weight) on alternate days for 30 days. Group III mice were subjected to whole body X-ray irradiation to cumulative dose of 2Gy (0.258Gy twice a day for four days in the last week). Group IV animals were pretreated with Aloe vera pulp extract on alternate days as in Group II and in the last week of the study, they were exposed to X-ray as in Group III. Results: Spleen of X-ray irradiated mice showed histopathological alterations accompanied with enhanced activity of lactate dehydrogenase (LDH) in serum. Elevated levels of reactive oxygen species (ROS), lipid peroxidation (LPO), enhanced activities in Glutathione based enzymes such as Glutathione peroxidase (GSH-Px), Glutathione reductase (GR), Catalase (CAT), Superoxide dismutase (SOD) associated with depletion in reduced Glutathione (GSH) concentration were observed after X-ray exposure in blood plasma and spleen.. Pro-inflammatory cytokines like tumor necrosis factors (TNF-α) and Inteleukin-6 (IL-6) levels were also found to be enhanced in serum of irradiated mice. Irradiation-induced significant elevation in Total leucocyte counts (TLC), neutrophil counts and decline in platelet counts, associated with unaltered levels of red blood cell counts (RBC’s) and haemoglobin (Hb) in various treatment groups. Clastogenic damage and apoptosis was also found to be increase in splenic tissue of X-ray exposed mice as assessed by micronucleus and TUNEL assay. However, X-ray irradiated animals administered with Aloe vera revealed significant improvement in levels of ROS/ LPO, LDH activity, and antioxidant mechanism. Aloe vera pretreated animals exhibited less severe damage, and early recovery in micronucleated cells, hematological parameters, apoptotic cells and inflammatory markers as compared to X-ray exposed mice. Conclusion: These results indicate that the radioprotective potential of Aloe vera against X-ray induced damage. This may be due to its free radical scavenging, antioxidant, anti-apoptotic and anti-inflammatory properties.Keywords: aloe vera, antioxidant defense system, lactate dehydrogenase (LDH), micronucleus assay, x-ray
Procedia PDF Downloads 19217602 Optimizing Approach for Sifting Process to Solve a Common Type of Empirical Mode Decomposition Mode Mixing
Authors: Saad Al-Baddai, Karema Al-Subari, Elmar Lang, Bernd Ludwig
Abstract:
Empirical mode decomposition (EMD), a new data-driven of time-series decomposition, has the advantage of supposing that a time series is non-linear or non-stationary, as is implicitly achieved in Fourier decomposition. However, the EMD suffers of mode mixing problem in some cases. The aim of this paper is to present a solution for a common type of signals causing of EMD mode mixing problem, in case a signal suffers of an intermittency. By an artificial example, the solution shows superior performance in terms of cope EMD mode mixing problem comparing with the conventional EMD and Ensemble Empirical Mode decomposition (EEMD). Furthermore, the over-sifting problem is also completely avoided; and computation load is reduced roughly six times compared with EEMD, an ensemble number of 50.Keywords: empirical mode decomposition (EMD), mode mixing, sifting process, over-sifting
Procedia PDF Downloads 39517601 Construction of Graph Signal Modulations via Graph Fourier Transform and Its Applications
Authors: Xianwei Zheng, Yuan Yan Tang
Abstract:
Classical window Fourier transform has been widely used in signal processing, image processing, machine learning and pattern recognition. The related Gabor transform is powerful enough to capture the texture information of any given dataset. Recently, in the emerging field of graph signal processing, researchers devoting themselves to develop a graph signal processing theory to handle the so-called graph signals. Among the new developing theory, windowed graph Fourier transform has been constructed to establish a time-frequency analysis framework of graph signals. The windowed graph Fourier transform is defined by using the translation and modulation operators of graph signals, following the similar calculations in classical windowed Fourier transform. Specifically, the translation and modulation operators of graph signals are defined by using the Laplacian eigenvectors as follows. For a given graph signal, its translation is defined by a similar manner as its definition in classical signal processing. Specifically, the translation operator can be defined by using the Fourier atoms; the graph signal translation is defined similarly by using the Laplacian eigenvectors. The modulation of the graph can also be established by using the Laplacian eigenvectors. The windowed graph Fourier transform based on these two operators has been applied to obtain time-frequency representations of graph signals. Fundamentally, the modulation operator is defined similarly to the classical modulation by multiplying a graph signal with the entries in each Fourier atom. However, a single Laplacian eigenvector entry cannot play a similar role as the Fourier atom. This definition ignored the relationship between the translation and modulation operators. In this paper, a new definition of the modulation operator is proposed and thus another time-frequency framework for graph signal is constructed. Specifically, the relationship between the translation and modulation operations can be established by the Fourier transform. Specifically, for any signal, the Fourier transform of its translation is the modulation of its Fourier transform. Thus, the modulation of any signal can be defined as the inverse Fourier transform of the translation of its Fourier transform. Therefore, similarly, the graph modulation of any graph signal can be defined as the inverse graph Fourier transform of the translation of its graph Fourier. The novel definition of the graph modulation operator established a relationship of the translation and modulation operations. The new modulation operation and the original translation operation are applied to construct a new framework of graph signal time-frequency analysis. Furthermore, a windowed graph Fourier frame theory is developed. Necessary and sufficient conditions for constructing windowed graph Fourier frames, tight frames and dual frames are presented in this paper. The novel graph signal time-frequency analysis framework is applied to signals defined on well-known graphs, e.g. Minnesota road graph and random graphs. Experimental results show that the novel framework captures new features of graph signals.Keywords: graph signals, windowed graph Fourier transform, windowed graph Fourier frames, vertex frequency analysis
Procedia PDF Downloads 34217600 Study of Biofuel Produced by Babassu Oil Fatty Acids Esterification
Authors: F. A. F. da Ponte, J. Q. Malveira, I. A. Maciel, M. C. G. Albuquerque
Abstract:
In this work aviation, biofuel production was studied by fatty acids (C6 to C16) esterification. The process variables in heterogeneous catalysis were evaluated using an experimental design. Temperature and reaction time were the studied parameters, and the methyl esters content was the response of the experimental design. An ion exchange resin was used as a heterogeneous catalyst. The process optimization was carried out using response surface methodology (RSM) and polynomial model of second order. Results show that the most influential variables on the linear coefficient of each effect studied were temperature and reaction time. The best result of methyl esters conversion in the experimental design was under the conditions: 10% wt of catalyst; 100 °C and 4 hours of reaction. The best-achieved conversion was 96.5% wt of biofuel.Keywords: esterification, ion-exchange resins, response surface methodology, biofuel
Procedia PDF Downloads 49617599 Institutional Transformation in a Finnish University of Applied Sciences
Authors: Perttu Heino
Abstract:
Universities of applied sciences (UASs) were introduced as part of the Finnish higher education system in the early 1990’s. Research, development and innovation (RDI) were mentioned in the legislation on UASs from the very beginning, but very little attention was paid to it in the early years of UASs due to reasons that are easy to understand. Required changes in the organization of the UAS and its educational offering were a big challenge, and it took several years to get things in order. There were RDI projects already then, but their number was low and there was no systematical coordination or management of those activities. In this paper, the institutional transformation of UASs is discussed based on how Tampere University of Applied Sciences has transformed during the years from a traditional tertiary level school to a modern higher education institution with a strong RDI activity, characterized by lively university-industry interaction and tight integration to education.Keywords: research, development, management, practices
Procedia PDF Downloads 3617598 The Effect of a Multidisciplinary Spine Clinic on Treatment Rates and Lead Times to Care
Authors: Ishan Naidu, Jessica Ryvlin, Devin Videlefsky
Abstract:
Introduction: Back pain is a leading cause of years lived with disability and economic burden, exceeding over $20 billion in healthcare costs not including indirect costs such as absence from work and caregiving. The multifactorial nature of back pain leads to treatment modalities administered by a variety of specialists, which are often disjointed. Multiple studies have found that patients receiving delayed physical therapy for lower back pain had higher medical-related costs from increased health service utilization as well as a reduced improvement in pain severity compared to early management. Uncoordinated health care delivery can exacerbate the physical and economic toll of the chronic condition, thus improvements in interdisciplinary, shared decision-making may improve outcomes. Objective: To assess whether a multidisciplinary spine clinic (MSC), consisting of orthopedic surgery, neurosurgery, pain medicine, and physiatry, alters interventional and non-interventional planning and treatment compared to a traditional unidisciplinary spine clinic (USC) including only orthopedic surgery. Methods: We conducted a retrospective cohort study with patients initially presenting for spine care to orthopedic surgeons between July 1, 2018 to June 30, 2019. Time to treatment recommendation, time to treatment and rates of treatment recommendations were assessed, including physical therapy, injections and surgery. Treatment rates were compared between MSC and USC using Pearson’s chi-square test logistic regression. Time to treatment recommendation and time to treatment were compared using log-rank test and Cox proportional hazard regression. All analyses were repeated for the propensity score (PS) matched subsample. Results: This study included 1,764 patients, with 692 at MSC and 1,072 at USC. Patients in MSC were more likely to be recommended injection when compared to USC (8.5% vs. 5.4%, p=0.01). When adjusted for confounders, the likelihood of injection recommendation remained greater in MSC than USC (Odds ratio [OR]=2.22, 95% CI: (1.39, 3.53), p=0.001). MSC was also associated with a shorter time to receiving injection recommendation versus USC (median: 21 vs. 32 days, log-rank: p<0.001; hazard ratio [HR]=1.90, 95% CI: (1.25, 2.90), p=0.003). MSC was associated with a higher likelihood of injection treatment (OR=2.27, 95% CI: (1.39, 3.73), p=0.001) and shorter lead time (HR=1.98, 95% CI: (1.27, 3.09), p=0.003). PS-matched analyses yielded similar conclusions. Conclusions: Care delivered at a multidisciplinary spine clinic was associated with a higher likelihood of recommending injection and a shorter lead time to injection administration when compared to a traditional unidisciplinary spine surgery clinic. Multidisciplinary clinics may facilitate coordinated care amongst different specialties resulting in increased utilization of less invasive treatment modalities while also improving care efficiency. The multidisciplinary clinic model is an important advancement in care delivery and communication, which can be used as a powerful method of improving patient outcomes as treatment guidelines evolve.Keywords: coordinated care, epidural steroid injection, multi-disciplinary, non-invasive
Procedia PDF Downloads 14017597 Oxalate Method for Assessing the Electrochemical Surface Area for Ni-Based Nanoelectrodes Used in Formaldehyde Sensing Applications
Authors: S. Trafela, X. Xua, K. Zuzek Rozmana
Abstract:
In this study, we used an accurate and precise method to measure the electrochemically active surface areas (Aecsa) of nickel electrodes. Calculated Aecsa is really important for the evaluation of an electro-catalyst’s activity in electrochemical reaction of different organic compounds. The method involves the electrochemical formation of Ni(OH)₂ and NiOOH in the presence of adsorbed oxalate in alkaline media. The studies were carried out using cyclic voltammetry with polycrystalline nickel as a reference material and electrodeposited nickel nanowires, homogeneous and heterogeneous nickel films. From cyclic voltammograms, the charge (Q) values for the formation of Ni(OH)₂ and NiOOH surface oxides were calculated under various conditions. At sufficiently fast potential scan rates (200 mV s⁻¹), the adsorbed oxalate limits the growth of the surface hydroxides to a monolayer. Although the Ni(OH)₂/NiOOH oxidation peak overlaps with the oxygen evolution reaction, in the reverse scan, the NiOOH/ Ni(OH)₂ reduction peak is well-separated from other electrochemical processes and can be easily integrated. The values of these integrals were used to correlate experimentally measured charge density with an electrochemically active surface layer. The Aecsa of the nickel nanowires, homogeneous and heterogeneous nickel films were calculated to be Aecsa-NiNWs = 4.2066 ± 0.0472 cm², Aecsa-homNi = 1.7175 ± 0.0503 cm² and Aecsa-hetNi = 2.1862 ± 0.0154 cm². These valuable results were expanded and used in electrochemical studies of formaldehyde oxidation. As mentioned nickel nanowires, heterogeneous and homogeneous nickel films were used as simple and efficient sensor for formaldehyde detection. For this purpose, electrodeposited nickel electrodes were modified in 0.1 mol L⁻¹ solution of KOH in order to expect electrochemical activity towards formaldehyde. The investigation of the electrochemical behavior of formaldehyde oxidation in 0.1 mol L⁻¹ NaOH solution at the surface of modified nickel nanowires, homogeneous and heterogeneous nickel films were carried out by means of electrochemical techniques such as cyclic voltammetric and chronoamperometric methods. From investigations of effect of different formaldehyde concentrations (from 0.001 to 0.1 mol L⁻¹) on electrochemical signal - current we provided catalysis mechanism of formaldehyde oxidation, detection limit and sensitivity of nickel electrodes. The results indicated that nickel electrodes participate directly in the electrocatalytic oxidation of formaldehyde. In the overall reaction, formaldehyde in alkaline aqueous solution exists predominantly in form of CH₂(OH)O⁻, which is oxidized to CH₂(O)O⁻. Taking into account the determined (Aecsa) values we have been able to calculate the sensitivities: 7 mA mol L⁻¹ cm⁻² for nickel nanowires, 3.5 mA mol L⁻¹ cm⁻² for heterogeneous nickel film and 2 mA mol L⁻¹ cm⁻² for heterogeneous nickel film. The detection limit was 0.2 mM for nickel nanowires, 0.5 mM for porous Ni film and 0.8 mM for homogeneous Ni film. All of these results make nickel electrodes capable for further applications.Keywords: electrochemically active surface areas, nickel electrodes, formaldehyde, electrocatalytic oxidation
Procedia PDF Downloads 16117596 Light-Weight Network for Real-Time Pose Estimation
Authors: Jianghao Hu, Hongyu Wang
Abstract:
The effective and efficient human pose estimation algorithm is an important task for real-time human pose estimation on mobile devices. This paper proposes a light-weight human key points detection algorithm, Light-Weight Network for Real-Time Pose Estimation (LWPE). LWPE uses light-weight backbone network and depthwise separable convolutions to reduce parameters and lower latency. LWPE uses the feature pyramid network (FPN) to fuse the high-resolution, semantically weak features with the low-resolution, semantically strong features. In the meantime, with multi-scale prediction, the predicted result by the low-resolution feature map is stacked to the adjacent higher-resolution feature map to intermediately monitor the network and continuously refine the results. At the last step, the key point coordinates predicted in the highest-resolution are used as the final output of the network. For the key-points that are difficult to predict, LWPE adopts the online hard key points mining strategy to focus on the key points that hard predicting. The proposed algorithm achieves excellent performance in the single-person dataset selected in the AI (artificial intelligence) challenge dataset. The algorithm maintains high-precision performance even though the model only contains 3.9M parameters, and it can run at 225 frames per second (FPS) on the generic graphics processing unit (GPU).Keywords: depthwise separable convolutions, feature pyramid network, human pose estimation, light-weight backbone
Procedia PDF Downloads 15417595 The Optimal Irrigation in the Mitidja Plain
Authors: Gherbi Khadidja
Abstract:
In the Mediterranean region, water resources are limited and very unevenly distributed in space and time. The main objective of this project is the development of a wireless network for the management of water resources in northern Algeria, the Mitidja plain, which helps farmers to irrigate in the most optimized way and solve the problem of water shortage in the region. Therefore, we will develop an aid tool that can modernize and replace some traditional techniques, according to the real needs of the crops and according to the soil conditions as well as the climatic conditions (soil moisture, precipitation, characteristics of the unsaturated zone), These data are collected in real-time by sensors and analyzed by an algorithm and displayed on a mobile application and the website. The results are essential information and alerts with recommendations for action to farmers to ensure the sustainability of the agricultural sector under water shortage conditions. In the first part: We want to set up a wireless sensor network, for precise management of water resources, by presenting another type of equipment that allows us to measure the water content of the soil, such as the Watermark probe connected to the sensor via the acquisition card and an Arduino Uno, which allows collecting the captured data and then program them transmitted via a GSM module that will send these data to a web site and store them in a database for a later study. In a second part: We want to display the results on a website or a mobile application using the database to remotely manage our smart irrigation system, which allows the farmer to use this technology and offers the possibility to the growers to access remotely via wireless communication to see the field conditions and the irrigation operation, at home or at the office. The tool to be developed will be based on satellite imagery as regards land use and soil moisture. These tools will make it possible to follow the evolution of the needs of the cultures in time, but also to time, and also to predict the impact on water resources. According to the references consulted, if such a tool is used, it can reduce irrigation volumes by up to up to 40%, which represents more than 100 million m3 of savings per year for the Mitidja. This volume is equivalent to a medium-size dam.Keywords: optimal irrigation, soil moisture, smart irrigation, water management
Procedia PDF Downloads 10917594 Tensile Behaviours of Sansevieria Ehrenbergii Fiber Reinforced Polyester Composites with Water Absorption Time
Authors: T. P. Sathishkumar, P. Navaneethakrishnan
Abstract:
The research work investigates the variation of tensile properties for the sansevieria ehrenbergii fiber (SEF) and SEF reinforced polyester composites respect to various water absorption time. The experiments were conducted according to ATSM D3379-75 and ASTM D570 standards. The percentage of water absorption for composite specimens was measured according to ASTM D570 standard. The fiber of SE was cut in to 30 mm length for preparation of the composites. The simple hand lay-up method followed by compression moulding process adopted to prepare the randomly oriented SEF reinforced polyester composites at constant fiber weight fraction of 40%. The surface treatment was done on the SEFs with various chemicals such as NaOH, KMnO4, Benzoyl Peroxide, Benzoyl Chloride and Stearic Acid before preparing the composites. NaOH was used for pre-treatment of all other chemical treatments. The morphology of the tensile fractured specimens studied using the Scanning Electron Microscopic. The tensile strength of the SEF and SEF reinforced polymer composites were carried out with various water absorption time such as 4, 8, 12, 16, 20 and 24 hours respectively. The result shows that the tensile strength was drop off with increase in water absorption time for all composites. The highest tensile property of raw fiber was found due to lowest moistures content. Also the chemical bond between the cellulose and cementic materials such as lignin and wax was highest due to lowest moisture content. Tensile load was lowest and elongation was highest for the water absorbed fibers at various water absorption time ranges. During this process, the fiber cellulose inhales the water and expands the primary and secondary fibers walls. This increases the moisture content in the fibers. Ultimately this increases the hydrogen cation and the hydroxide anion from the water. In tensile testing, the water absorbed fibers shows highest elongation by stretching of expanded cellulose walls and the bonding strength between the fiber cellulose is low. The load carrying capability was stable at 20 hours of water absorption time. This could be directly affecting the interfacial bonding between the fiber/matrix and composite strength. The chemically treated fibers carry higher load and lower elongation which is due to removal of lignin, hemicellulose and wax content. The water time absorption decreases the tensile strength of the composites. The chemically SEF reinforced composites shows highest tensile strength compared to untreated SEF reinforced composites. This was due to highest bonding area between the fiber/matrix. This was proven in the morphology at the fracture zone of the composites. The intra-fiber debonding was occurred by water capsulation in the fiber cellulose. Among all, the tensile strength was found to be highest for KMnO4 treated SEF reinforced composite compared to other composites. This was due to better interfacial bonding between the fiber-matrix compared to other treated fiber composites. The percentage of water absorption of composites increased with time of water absorption. The percentage weight gain of chemically treated SEF composites at 4 hours to zero water absorption are 9, 9, 10, 10.8 and 9.5 for NaOH, BP, BC, KMnO4 and SA respectively. The percentage weight gain of chemically treated SEF composites at 24 hours to zero water absorption 5.2, 7.3, 12.5, 16.7 and 13.5 for NaOH, BP, BC, KMnO4 and SA respectively. Hence the lowest weight gain was found for KMnO4 treated SEF composites by highest percentage with lowest water uptake. However the chemically treated SEF reinforced composites is possible materials for automotive application like body panels, bumpers and interior parts, and household application like tables and racks etc.Keywords: fibres, polymer-matrix composites (PMCs), mechanical properties, scanning electron microscopy (SEM)
Procedia PDF Downloads 41017593 Business Continuity Risk Review for a Large Petrochemical Complex
Authors: Michel A. Thomet
Abstract:
A discrete-event simulation model was used to perform a Reliability-Availability-Maintainability (RAM) study of a large petrochemical complex which included sixteen process units, and seven feeds and intermediate streams. All the feeds and intermediate streams have associated storage tanks, so that if a processing unit fails and shuts down, the downstream units can keep producing their outputs. This also helps the upstream units which do not have to reduce their outputs, but can store their excess production until the failed unit restart. Each process unit and each pipe section carrying the feeds and intermediate streams has a probability of failure with an associated distribution and a Mean Time Between Failure (MTBF), as well as a distribution of the time to restore and a Mean Time To Restore (MTTR). The utilities supporting the process units can also fail and have their own distributions with specific MTBF and MTTR. The model runs are for ten years or more and the runs are repeated several times to obtain statistically relevant results. One of the main results is the On-Stream factor (OSF) of each process unit (percent of hours in a year when the unit is running in nominal conditions). One of the objectives of the study was to investigate if the storage capacity of each of the feeds and the intermediate stream was adequate. This was done by increasing the storage capacities in several steps and through running the simulation to see if the OSF were improved and by how much. Other objectives were to see if the failure of the utilities were an important factor in the overall OSF, and what could be done to reduce their failure rates through redundant equipment.Keywords: business continuity, on-stream factor, petrochemical, RAM study, simulation, MTBF
Procedia PDF Downloads 21917592 The Impact of Online Games, Massively Multiplayer Online Game towards Undergraduate Students in Malaysia
Authors: Rubijesmin Abdul Latif, Norshakirah Abdul Aziz, Mohd Taufik Abdul Jalil
Abstract:
This paper focuses on the impact of online games among Malaysian undergraduate students. The purpose of this study is to investigate whether online games (especially MMOGs) impacted students positively or vice versa; focusing on three elements (time management, social life, and emotion). A total of 83 respondents comprised from 14 Malaysia universities, randomly selected undergraduate students who play MMOGs (casual and hardcore gamers i.e. addiction to MMOGs) were involved in this study. The results showed that MMOGs have only negative impact on students capabilities in time management, meanwhile as for the elements social life and emotion, MMOGs do not affect them negatively.Keywords: internet game addiction, online games, MMOGs, impact, undergraduate students
Procedia PDF Downloads 58317591 Space Time Adaptive Algorithm in Bi-Static Passive Radar Systems for Clutter Mitigation
Authors: D. Venu, N. V. Koteswara Rao
Abstract:
Space – time adaptive processing (STAP) is an effective tool for detecting a moving target in spaceborne or airborne radar systems. Since airborne passive radar systems utilize broadcast, navigation and excellent communication signals to perform various surveillance tasks and also has attracted significant interest from the distinct past, therefore the need of the hour is to have cost effective systems as compared to conventional active radar systems. Moreover, requirements of small number of secondary samples for effective clutter suppression in bi-static passive radar offer abundant illuminator resources for passive surveillance radar systems. This paper presents a framework for incorporating knowledge sources directly in the space-time beam former of airborne adaptive radars. STAP algorithm for clutter mitigation for passive bi-static radar has better quantitation of the reduction in sample size thereby amalgamating the earlier data bank with existing radar data sets. Also, we proposed a novel method to estimate the clutter matrix and perform STAP for efficient clutter suppression based on small sample size. Furthermore, the effectiveness of the proposed algorithm is verified using MATLAB simulations in order to validate STAP algorithm for passive bi-static radar. In conclusion, this study highlights the importance for various applications which augments traditional active radars using cost-effective measures.Keywords: bistatic radar, clutter, covariance matrix passive radar, STAP
Procedia PDF Downloads 29617590 Radical Web Text Classification Using a Composite-Based Approach
Authors: Kolade Olawande Owoeye, George R. S. Weir
Abstract:
The widespread of terrorism and extremism activities on the internet has become a major threat to the government and national securities due to their potential dangers which have necessitated the need for intelligence gathering via web and real-time monitoring of potential websites for extremist activities. However, the manual classification for such contents is practically difficult or time-consuming. In response to this challenge, an automated classification system called composite technique was developed. This is a computational framework that explores the combination of both semantics and syntactic features of textual contents of a web. We implemented the framework on a set of extremist webpages dataset that has been subjected to the manual classification process. Therein, we developed a classification model on the data using J48 decision algorithm, this is to generate a measure of how well each page can be classified into their appropriate classes. The classification result obtained from our method when compared with other states of arts, indicated a 96% success rate in classifying overall webpages when matched against the manual classification.Keywords: extremist, web pages, classification, semantics, posit
Procedia PDF Downloads 14517589 A Case Study: Beginning Teacher's Experiences of Mentoring in Secondary Education
Authors: Abdul Rofiq Badril Rizal M. Z.
Abstract:
This case study examines the experiences of four beginning teachers currently working in New South Wales secondary schools. Data were collected from semi-structured interviews conducted one on one over the period of one month. The data were coded with findings reported through key areas of discovery, which linked to the research presented in the literature review. The participants involved in the case study all reported positive experiences with mentoring, though none were given the opportunity to take part in a formal mentoring program, and all the mentors offered their time voluntarily. The mentoring took different forms, but the support most valued by the participants was the emotional and curriculum related supported received. All participants wished they had greater access to mentoring and felt it would have benefits for most beginning teachers. The study highlights ongoing issues around the lack of access to mentoring, which could be due to factors such as funding, time and training.Keywords: mentor, mentee, pre-service teacher, beginning teacher
Procedia PDF Downloads 10817588 The Use of Degradation Measures to Design Reliability Test Plans
Authors: Stephen V. Crowder, Jonathan W. Lane
Abstract:
With short production development times, there is an increased need to demonstrate product reliability relatively quickly with minimal testing. In such cases there may be few if any observed failures. Thus it may be difficult to assess reliability using the traditional reliability test plans that measure only time (or cycles) to failure. For many components, degradation measures will contain important information about performance and reliability. These measures can be used to design a minimal test plan, in terms of number of units placed on test and duration of the test, necessary to demonstrate a reliability goal. In this work we present a case study involving an electronic component subject to degradation. The data, consisting of 42 degradation paths of cycles to failure, are first used to estimate a reliability function. Bootstrapping techniques are then used to perform power studies and develop a minimal reliability test plan for future production of this component.Keywords: degradation measure, time to failure distribution, bootstrap, computational science
Procedia PDF Downloads 53217587 Electrophilic Halogen-Induced Spirocyclization of 2-Alkynolylaryloate Esters
Authors: Krittapast Dara-Opast, Sureeporn Ruengsangtongkul, Jumreang Tummatorn, Kittipong Chainok, Onrapak Reamtong, Somsak Ruchirawat, Charnsak Thongsornkleeb
Abstract:
Selective synthesis of gem-dihalo spiroisobenzofuran and spiroisocoumarin can be performed via halogenative double cyclization of methyl 2-(hydroxyalk-1-yn-1-yl) benzoates in the presence of either N-chlorosuccinimide (NCS) or N-bromosuccinimide (NBS) and chlorotrimethylsilane (TMSCl). The combination of NCS and TMSCl led to the generation of electrophilic chlorine in situ, which activated the alkyne functional group of the substrate leading to the cyclization via either 5-exo-dig or 6-endo-dig mode of cyclization to produce the target compounds in moderate yields. The protocol could be carried on a broad scope of substrates under mild conditions (0 °C to rt). The parent compounds showed good antiparasitic activity compared to standard drug albendazole. Further investigation of the scope of the reaction and their antiparasitic activities is underway.Keywords: antiparasitic activities, halogenative annulation, spirocycles, spirocyclization
Procedia PDF Downloads 190