Search results for: frequency and voltage regulation

Authors: Pedro Esteban

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Most installations nowadays are exposed to many power quality problems, and they also face numerous challenges to comply with grid code and energy efficiency requirements. The reason behind this is that they are not designed to support nonlinear, non-balanced, and variable loads and generators that make up a large percentage of modern electric power systems. These problems and challenges become especially critical when designing green buildings and smart cities. These problems and challenges are caused by equipment that can be typically found in these installations like variable speed drives (VSD), transformers, lighting, battery chargers, double-conversion UPS (uninterruptible power supply) systems, highly dynamic loads, single-phase loads, fossil fuel generators and renewable generation sources, to name a few. Moreover, events like capacitor switching (from existing capacitor banks or passive harmonic filters), auto-reclose operations of transmission and distribution lines, or the starting of large motors also contribute to these problems and challenges. Active power filters (APF) are one of the fastest-growing power electronics technologies for solving power quality problems and meeting grid code and energy efficiency requirements for a wide range of segments and applications. They are a high performance, flexible, compact, modular, and cost-effective type of power electronics solutions that provide an instantaneous and effective response in low or high voltage electric power systems. They enable longer equipment lifetime, higher process reliability, improved power system capacity and stability, and reduced energy losses, complying with most demanding power quality and energy efficiency standards and grid codes. There can be found several types of active power filters, including active harmonic filters (AHF), static var generators (SVG), active load balancers (ALB), hybrid var compensators (HVC), and low harmonic drives (LHD) nowadays. All these devices can be used in applications in Smart Cities bringing several technical and economic benefits.

Keywords: power quality improvement, energy efficiency, grid code compliance, green buildings, smart cities

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Authors: I. Stacher, B. Schrank, K. Stiehl, K. A. Woodcock

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Background: The need and desire for connectedness and belonging to a peer group is a major concern in middle childhood. This is particularly true for the period of school transition when making and maintaining friendships is put to the test. Social relations are important for enhancing self-esteem, confidence, and mental health. Conflicts with peers and victimization mark challenges in the complex social environment of early adolescents. Thus, the promotion of supportive peer relationships is an important social goal. The current literature lacks an in-depth analysis of young people’s experiences connected to making and maintaining friendships. Aim: This qualitative study aims to understand the factors that facilitate and hinder friendship and peer relations within the complex context of school transition. Methods: Youth engagement workshops at primary and secondary schools were conducted with 53 classes (N = 906 pupils; M age = 10.44; SD = .912) in 29 different schools across lower Austria. A big poster was created with the entire class, collecting early adolescents’ ideas on ways they can support each other in the school environment. Then, students were divided into smaller groups and encouraged to share their personal experiences of friendship. Verbatim quotes from students were collected on observation sheets and sticky notes during the activities. A thematic analysis was conducted. Results: Early adolescents describe facilitating factors that allow them to connect with peers. These descriptions are mainly on a behavioral level and are relevant for face-to-face and digital contact, e.g., practical and emotional support, spending time together, pleasure and fun. Specific challenges such as offensive actions, betrayal, and lack of emotion regulation exist and need to be addressed if aiming to reduce barriers between peers. Conclusion: Knowing first-hand experiences, desires, and barriers for making and maintaining friends at the time of school transition will help researchers to develop preventive health programs that adequately address the needs and preferences of today’s youth.

Keywords: youth voice, experts by experience, friendship, peer relations, primary-secondary school, transition

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Authors: Mohamed N. Al-Arifi, Hessa Othman Al-Husein, Mostafa Q. Al Shamiri, Ragab Said, Syed Wajid, Salmeen D. Babelghaith

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Polypharmacy was defined as a taking more than 4 medications per single patients (minor polypharmacy), patients who are taking more than 10 medications we considered as a major polypharmacy. This study was aimed to evaluate the prevalence of polypharmacy in elderly Saudi cardiac patient. A retrospective observational study was carried out at the department of CCU and cardiology unit of the King Fahad cardiac centre (KFCC) in King Khalid university hospital from May 2012 to October 2012. All Parameters was analyzed by using Statistical Packages for Social Science (SPSS) to conclude the result; tests of association were performed using the chi-square statistic. The mean age of patients was 70.1 ± 7.75 years, more than half 83 (51.6%) were males. The highest frequency of chronic diseases found were hypertension (91.0%) followed by, dyslipidemia (74.9%), and diabetes mellitus. Results showed that 82% had polypharmacy (>4 drugs) during the study period, and 47.9% had major polypharmacy. The incidence of inappropriate drug use was found to be higher with men than female (p = 0.984). In conclusion, this study revealed that high prevalence of polypharmacy and potentially inappropriate medications in elderly Saudi cardiac inpatients.

Keywords: cardiac inpatients, medications, polypharmacy, prevalence

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Authors: Alcardo Alex Barakabitze, Tan Xiaoheng

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Orthogonal Frequency Division Multiplexing (OFDM) is a special case of Multi-Carrier Modulation (MCM) technique which transmits a stream of data over a number of lower data rate subcarriers. OFDM splits the total transmission bandwidth into a number of orthogonal and non-overlapping subcarriers and transmit the collection of bits called symbols in parallel using these subcarriers. This paper explores the Peak to Average Power Reduction (PAPR) using the Partial Transmit Sequence technique. We provide the distribution analysis and the basics of OFDM signals and then show how the PAPR increases as the number of subcarriers increases. We provide the performance analysis of CCDF and PAPR expressed in decibels through MATLAB simulations. The simulation results show that, in PTS technique, the performance of PAPR reduction in OFDM systems improves significantly as the number of sub-blocks increases. However, by keeping the same number of sub-blocks variation, oversampling factor and the number of OFDM blocks’ iteration for generating the CCDF, the OFDM systems with 128 subcarriers have an improved performance in PAPR reduction compared to OFDM systems with 256, 512 or >512 subcarriers.

Keywords: OFDM, peak to average power reduction (PAPR), bit error rate (BER), subcarriers, wireless communications

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Authors: T. Aldeeb, M. Abduelmula

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This study examines the fatigue life of S275 mild steel at room temperature. Mechanical components can fail under cyclic loading during period of time, known as the fatigue phenomenon. In order to prevent fatigue induced failures, material behavior should be investigated to determine the endurance limit of the material for safe design and infinite life, thus leading to reducing the economic cost and loss in human lives. The fatigue behavior of S275 mild steel was studied and investigated. Specimens were prepared in accordance with ASTM E3-11, and fatigue tests of the specimen were conducted in accordance with ASTM E466-07 on a smooth plate, with a continuous radius between ends (hourglass-shaped plate). The method of fatigue testing was applied with constant load amplitude and constant frequency of 4 Hz with load ratio (Fully Reversal R= -1). Surface fractures of specimens were investigated using Scanning Electron Microscope (SEM). The experimental results were compared with the results of a Finite Element Analysis (FEA), using simulation software. The experiment results indicated that the endurance fatigue limit of S275 mild steel was 195.47 MPa.

Keywords: fatigue strength, fatigue life, finite element analysis(FEA), S275 mild steel, scanning electron microscope (SEM)

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Authors: Emmanuel Ekwueme, Anwar Ali

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As the Internet of Things (IoT) continues to expand, the demand for battery-free devices is increasing, which is crucial for the efficiency of 5G networks and eco-friendly industrial systems. The solution is a device that operates indefinitely, requires no maintenance, and has no negative impact on the ambient environment. One promising approach to achieve this is energy harvesting, which involves capturing energy from the ambient environment and transferring it to power devices. This method can revolutionize industries. Such as manufacturing, agriculture, and healthcare by enabling real-time data collection and analysis, reducing maintenance costs, improving efficiency, and contributing to a future with lower carbon emissions. This research explores various energy harvesting techniques, focusing on radio frequencies (RF) and multiple energy sources. It examines RF-based and solar methods for powering battery-free sensors, low-power circuits, and IoT devices. The study investigates a hybrid RF-solar harvesting circuit designed for remote sensing devices. The proposed system includes distinct RF and solar energy harvester circuits, with the RF harvester operating at 2.45GHz and the solar harvester utilizing a maximum power point tracking (MPPT) algorithm to maximize efficiency.

Keywords: radio frequency, energy harvesting, Internet of Things (IoT), multisource, solar energy

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Authors: Souvik Das, Janak Lal, Arthita Dey, Goutam Mukhopadhyay, Sandip Bhattacharya

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Telescopic Front Fork (TFF) used in two wheelers, mainly motorcycle, is made from high strength steel, and is manufactured by high frequency induction welding process wherein hot rolled and pickled coils are used as input raw material for rolling of hollow tubes followed by heat treatment, surface treatment, cold drawing, tempering, etc. The final application demands superior quality TFF tubes w.r.t. surface finish and dimensional tolerances. This paper presents the investigation of two different types of failure of fork during operation. The investigation consists of visual inspection, chemical analysis, characterization of microstructure, and energy dispersive spectroscopy. In this paper, comprehensive investigations of two failed tube samples were investigated. In case of Sample #1, the result revealed that there was a pre-existing crack, known as hook crack, which leads to the cracking of the tube. Metallographic examination exhibited that during field operation the pre-existing hook crack was surfaced out leading to crack in the pipe. In case of Sample #2, presence of internal oxidation with decarburised grains inside the material indicates origin of the defect from slab stage.

Keywords: telescopic front fork, induction welding, hook crack, internal oxidation

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Authors: Katarzyna Stoklosa

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Introduction: European Public Prosecutor’s Office (EPPO) is an independent office in European Union which was established under the article 86 of the Treaty on the Functioning of the European Union by the Treaty of Lisbon following the method of enhanced cooperation. EPPO is aimed at combating crimes against the EU’s financial interest et fraud against the EU budgets on the one hand, EPPO will give a chance to effective fight with organized criminality, on the other it seems to be a threat for member-states which bound with justice the problem of sovereignty. It is a new institution that will become effective from 2020, which is why it requires prior analysis. Methodology: The author uses statistical and comparative methods by collecting and analyzing the work of current institutions such as Europol, Eurojust, as well as the future impact of EPPO on detection and prosecution of crimes. The author will also conduct questionnaire among students and academic staff involved in the perception of EU institutions and the need to create new entities dealing with inter-agency cooperation in criminal matters. Thanks to these research the author will draw up present ways of cooperation between member-states and changes in fighting with financial crimes which will grow up under new regulation. Major Finding of the Study: Analysis and research show that EPPO is an institution based on the principle of mutual recognition, which often does not work in cooperation between Member States. Distrust and problems with the recognition of judgments of other EU Member States may significantly affect the functioning of EPPO. Poland is not part of the EPPO, because arguments have been raised that the European Public Prosecutor's Office interferes too much with the Member States’ pro-active sovereignty and duplicates competences. The research and analyzes carried out by the author show that EPPO has completely new competences, for example, it may file indictments against perpetrators of financial crimes. However, according to the research carried out by the author, such competences may undermine the sovereignty and the principle of protecting the public order of the EU. Conclusion: After the analysis, it will be possible to set following thesis: EPPO is only possible way to effective fight with organized financial criminality. However in conclusion Polish doubts should not be criticized at all. Institutions as EPPO must properly respect sovereignty of member-states. Even instruments like that cannot provoke political contraventions, because there are no other ways to effective resolving of international criminality problem.

Keywords: criminal trial, economic crimes, European Public Prosecutor's Office, European Union

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Authors: Urvee B. Trivedi, U. D. Dalal

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As wireless communication services grow quickly; the seriousness of spectrum utilization has been on the rise gradually. An emerging technology, cognitive radio has come out to solve today’s spectrum scarcity problem. To support the spectrum reuse functionality, secondary users are required to sense the radio frequency environment, and once the primary users are found to be active, the secondary users are required to vacate the channel within a certain amount of time. Therefore, spectrum sensing is of significant importance. Once sensing is done, different prediction rules apply to classify the traffic pattern of primary user. Primary user follows two types of traffic patterns: periodic and stochastic ON-OFF patterns. A cognitive radio can learn the patterns in different channels over time. Two types of classification methods are discussed in this paper, by considering edge detection and by using autocorrelation function. Edge detection method has a high accuracy but it cannot tolerate sensing errors. Autocorrelation-based classification is applicable in the real environment as it can tolerate some amount of sensing errors.

Keywords: cognitive radio (CR), probability of detection (PD), probability of false alarm (PF), primary user (PU), secondary user (SU), fast Fourier transform (FFT), signal to noise ratio (SNR)

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Authors: Julinda Keçi

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In many countries, governments have been promoting the involvement of private sector entities to enter into long-term agreements for the development and delivery of large infrastructure projects, with a focus on overcoming the limitations upon public fund of the traditional approach. The involvement of private sector through public-private partnerships (PPP) brings in new capital investments, value for money and additional risks to handle. Worldwide research studies have shown that an objective, systematic, reliable and user-oriented risk assessment process and an optimal allocation mechanism among different stakeholders is crucial to the successful completion. In this framework this paper, which is the first stage of a research study, aims to identify the main risks for the delivery of PPP projects. A review of cross-countries research projects and case studies was performed to map the key risks affecting PPP infrastructure delivery. The matrix of mapping offers a summary of the frequency of factors, clustered in eleven categories: Construction, Design, Economic, Legal, Market, Natural, Operation, Political, Project finance, Project selection and Relationship. Results will highlight the most critical risk factors, and will hopefully assist the project managers in directing the managerial attention in the further stages of risk allocation.

Keywords: construction, infrastructure, public private partnerships, risks

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Authors: Moftah BinHasan

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Induction motors (IM) are vital components in industrial processes whose failure may yield to an unexpected interruption at the industrial plant, with highly incurred consequences in costs, product quality, and safety. Among different detection approaches proposed in the literature, that based on stator current monitoring termed as Motor Current Signature Analysis (MCSA) is the most preferred. MCSA is advantageous due to its non-invasive properties. The popularity of motor current signature analysis comes from being that the current consists of motor harmonics, around the supply frequency, which show some properties related to different situations of healthy and faulty conditions. One of the techniques used with machine line current resorts to spectrum analysis. Besides discussing the fundamentals of MCSA and its applications in the condition monitoring arena, this paper shows a summary of the most frequent faults and their consequence signatures on the stator current spectrum of an induction motor. In addition, this article presents different case studies of induction motor fault diagnosis. These faults were seeded in the machine which was run for more than an hour for each test before the results were recorded for the faulty situations. These results are then compared with those for the healthy cases that were recorded earlier.

Keywords: induction motor, condition monitoring, fault diagnosis, MCSA, rotor, stator, bearing, eccentricity

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Authors: N. Boutaghane, F. Z. Tounsi

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Many physical and technological factors degrade the SPECT images, both qualitatively and quantitatively. For this, it is not always put into leading technological advances to improve the performance of tomographic gamma camera in terms of detection, collimation, reconstruction and correction of tomographic images methods. We have to master firstly the choice of various acquisition and reconstruction parameters, accessible to clinical cases and using the attenuation and scatter correction methods to always optimize quality image and minimized to the maximum dose received by the patient. In this work, an evaluation of qualitative and quantitative tomographic images is performed based on the acquisition parameters (counts per projection) and reconstruction parameters (filter type, associated cutoff frequency). In addition, methods for correcting physical effects such as attenuation and scatter degrading the image quality and preventing precise quantitative of the reconstructed slices are also presented. Two approaches of attenuation and scatter correction are implemented: the attenuation correction by CHANG method with a filtered back projection reconstruction algorithm and scatter correction by the subtraction JASZCZAK method. Our results are considered as such recommandation, which permits to determine the origin of the different artifacts observed both in quality control tests and in clinical images.

Keywords: attenuation, scatter, reconstruction filter, image quality, acquisition and reconstruction parameters, SPECT

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Authors: Patti Kastanias, Wei Wang, Karyn Mackenzie, Sandra Robinson, Susan Wnuk

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Obesity is a worldwide epidemic and is recognized as a chronic disease. Pain in the obese individual is a multidimensional issue. An increase in BMI is positively correlated with pain incidence and severity, especially in central obesity where individuals are twice as likely to have chronic pain. Both obesity and chronic pain are also associated with mood disorders. Pain is worse among obese individuals with depression and anxiety. Bariatric surgery provides patients with an effective solution for long-term weight loss and associated health problems. However, not much is known about acute and chronic pain after bariatric surgery and its contributing factors, including mood disorders. Nurse practitioners (NPs) at one large multidisciplinary bariatric surgery centre led two studies to examine acute and chronic pain and pain management over time after bariatric surgery. The purpose of the initial study was to examine the incidence and severity of acute and chronic pain after bariatric surgery. The aim of the secondary study was to further examine chronic pain, specifically looking at psychological factors that influence severity or incidence of both neuropathic and somatic pain as well as changes in opioid use. The initial study was a prospective, longitudinal study where patients having bariatric surgery at one surgical center were followed up to 6 months postop. Data was collected at 7 time points using validated instruments for pain severity, pain interference, and patient satisfaction. In the second study, subjects were followed longitudinally starting preoperatively and then at 6 months and 1 year postoperatively to capture changes in chronic pain and influencing variables over time. Valid and reliable instruments were utilized for all major study outcomes. In the first study, there was a trend towards decreased acute post-operative pain over time. The incidence and severity of chronic pain was found to be significantly reduced at 6 months post bariatric surgery. Interestingly, interference of chronic pain in daily life such as normal work, mood, and walking ability was significantly improved at 6 months postop however; this was not the case with sleep. Preliminary results of the secondary study indicate that pain severity, pain interference, anxiety and depression are significantly improved at 6 months postoperatively. In addition, preoperative anxiety, depression and emotional regulation were predictive of pain interference, but not pain severity. The results of our regression analyses provide evidence for the impact of pre-existing psychological factors on pain, particularly anxiety in obese populations.

Keywords: bariatric surgery, mood disorders, obesity, pain

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Authors: Kanae Suzuki

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Handheld video games are popular communication tools among Japanese elementary school students today. This study aims to examine the effects of the use of handheld video games on interpersonal relationships of the students in real and virtual worlds. A two-wave panel survey was conducted for students of ten elementary schools at an interval of approximately six months. The survey questionnaire included questions about the average amount of time spent playing a handheld video game during the past one month, the frequency of communication with players during game play, and the interpersonal relationships, such as the number of real and virtual friends the students have. A multiple regression model was constructed for 324 students to examine causal relationships. The results indicated that the more frequently the students communicated with other players while playing games, the number of the real friends tended to increase. In contrast, no significant effect of the total time spent playing games was found on interpersonal relationships. The findings suggested that communication during game play is an important factor for improving interpersonal relationships of this age group.

Keywords: communication, real friend, social adjustment, virtual friend

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Authors: Ahmed Krobba, Meriem Touzene, Mohamed Debeyche

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The wireless communications system (5G) will provide more diverse applications and higher quality services for users compared to the long-term evolution 4G (LTE). 5G uses a higher carrier frequency, which suffers from information loss in 5G coverage. Most 5G users often cannot obtain high-quality communications due to transmission channel noise and channel complexity. Physical Uplink Control Channel (PUCCH-NR: Physical Uplink Control Channel New Radio) plays a crucial role in 5G NR telecommunication technology, which is mainly used to transmit link control information uplink (UCI: Uplink Control Information. This study based of evaluating the performance of channel physical uplink control PUCCH-NR under low Signal-to-Noise Ratios with various antenna numbers reception. We propose the artificial intelligence approach based on deep neural networks (Deep Learning) to estimate the PUCCH-NR channel in comparison with this approach with different conventional methods such as least-square (LS) and minimum-mean-square-error (MMSE). To evaluate the channel performance we use the block error rate (BLER) as an evaluation criterion of the communication system. The results show that the deep neural networks method gives best performance compared with MMSE and LS

Keywords: 5G network, uplink (Uplink), PUCCH channel, NR-PUCCH channel, deep learning

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Authors: Abrar Abuzaid, Maha Alaaeddine, Haya Alesayi

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This project is centered around understanding the usage and impact of Alexa, Amazon's popular virtual assistant, in everyday life. Alexa, known for its integration into devices like Amazon Echo, offers functionalities such as voice interaction, media control, providing real-time information, and managing smart home devices. Our primary focus is to conduct a straightforward survey aimed at uncovering how people use Alexa in their daily routines. We plan to reach out to a wide range of individuals to get a diverse perspective on how Alexa is being utilized for various tasks, the frequency and context of its use, and the overall user experience. The survey will explore the most common uses of Alexa, its impact on daily life, features that users find most beneficial, and improvements they are looking for. This project is not just about collecting data but also about understanding the real-world applications of a technology like Alexa and how it fits into different lifestyles. By examining the responses, we aim to gain a practical understanding of Alexa's role in homes and possibly in workplaces. This project will provide insights into user satisfaction and areas where Alexa could be enhanced to meet the evolving needs of its users. It’s a step towards connecting technology with everyday life, making it more accessible and user-friendly

Keywords: Amazon Alexa, artificial intelligence, smart speaker, natural language processing

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Authors: Sherif Refaat, Hassan Aref

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Background: Although asthma is a well-identified presentation to the emergency department, little is known about the frequency and percentage of respiratory and non-respiratory symptoms in patients with acute asthma in the emergency department (ED). Objective: The aim of this study is to identify the relationship between acute asthma exacerbation and different respiratory and non-respiratory symptoms including chest pain encountered by patients visiting the emergency department. Subjects and methods: Prospective study included 169 (97 females and 72 males) asthmatic patients who were admitted to emergency department of two tertiary care facility hospitals for asthma exacerbation from the period of September 2010 to August 2013, an anonyms questionnaire was used to collect symptoms and analysis of symptoms. Results: Females were 97 (57%) of the patients, mean age was 35.6 years; dyspnea on exertion was the commonest symptom accounting for 161 (95.2%) of patients, followed by dyspnea at rest 155 (91.7%), wheezing in 152 (89.9%), chest pain was present in 82 patients (48.5%), the pain was burning in 36 (43.9%) of the total patients with chest pain. Non-respiratory symptoms were seen frequently in acute asthma in ED. Conclusions: Dyspnea was the commonest chest symptoms encountered in patients with acute asthma followed by wheezing. Chest pain in acute asthma is a common symptom and should be fully studied to exclude misdiagnosis as of cardiac origin; there is a need for a better dissemination of knowledge about this disease association with chest pain. It was also noted that other non-respiratory symptoms are frequently encountered with acute asthma in emergency department.

Keywords: asthma, emergency department, respiratory symptoms, non respiratory system

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Authors: R. Vidyasagar, G. L. S. Vilela, B. M. Guiraldelli, A. B. Henriques, J. Moodera

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Nano-scaled magnetic systems that can have both magnetic and optical transitions controlled and manipulated by external means have received enormous research attention for their potential applications in magneto-optics and spintronic devices. Among several ferrimagnetic insulators, the Tm₃Fe₅O₁₂ (TmIG) has become a prototype material displaying huge perpendicular magnetic anisotropy. Nevertheless, the optical properties of nano-scale TnIG films have not yet been investigated. We report the observation of giant splitting in the optical transitions of high-quality thin films of Tm₃Fe₅O₁₂ (TmIG) grown by rf sputtering on gadolinium gallium garnet substrates (GGG-111) substrate. The optical absorbance profiles measured with optical absorption spectroscopy show a dual optical transition in visible frequency regimes attributed to the transitions of electrons from the O-2p valence band to the Fe-3d conduction band and from the O-2p valence band to the Fe-2p⁵3d⁶ excitonic states at the Γ-symmetric point of the TmIG Brillouin zone. When the thickness of the film is reduced from 120 nm to 7.5 nm, the 1st optical transition energy shifted from 2.98 to 3.11 eV ( ~130 meV), and the 2nd transition energy shifted from 2.62 to 2.56 eV (~ 60 meV). The giant band splitting of both transitions can be attributed to the population of excited states associated with the atomic modification pertaining to the compressive or tensile strains.

Keywords: optical transitions, thin films, ferrimagnetic insulator, strains

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Authors: Shakir H. Mohammed Al-Alwany, Saad Hasan M. Ali, Ibrahim Mohammed S. Shnawa

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The study was aimed to define the percentage of detection of high-oncogenic risk types of HPV and their genotyping in archival tissue specimens that ranged from apparently healthy tissue to invasive breast cancer by using one of the recent versions of In Situ Hybridization(ISH) 0.2. To find out rational significance of such genotypes as well as over expressed products of mutants P53 and RB genes on the severity of underlying breast cancers. The DNA of HPV was detected in 46.5 % of tissues from breast cancers while HPV DNA in the tissues from benign breast tumours was detected in 12.5%. No HPV positive–ISH reaction was detected in healthy breast tissues of the control group. HPV DNA of genotypes (16, 18, 31 and 33) was detected in malignant group in frequency of 25.6%, 27.1%, 30.2% and 12.4%, respectively. Over expression of p53 was detected by IHC in 51.2% breast cancer cases and in 50% benign breast tumour group, while none of control group showed P53- over expression. Retinoblastoma protein was detected by IHC test in 49.7% of malignant breast tumours, 54.2% of benign breast tumours but no signal was reported in the tissues of control group. The significance prevalence of expression of mutated p53 & Rb genes as well as detection of high-oncogenic HPV genotypes in patients with breast cancer supports the hypothesis of an etiologic role for the virus in breast cancer development.

Keywords: human papilloma virus, P53, RB, breast cancer

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Authors: Houari Boumediene University of Science, Technology.

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"Various methods are typically used in the dynamic analysis of transversely vibrating beams. To achieve this, numerical methods are used to solve the general eigenvalue problem. The equations of equilibrium, which describe the motion, are derived from a fourth-order differential equation. Our study is based on the finite element method, and the results of the investigation are the vibration frequencies obtained using the Jacobi method. Two types of elementary mass matrices are considered: one representing a uniform distribution of mass along the element and the other consisting of concentrated masses located at fixed points whose number increases progressively with equal distances at each evaluation stage. The beams studied have different boundary constraints, representing several classical situations. Comparisons are made for beams where the distributed mass is replaced by n concentrated masses. As expected, the first calculation stage involves determining the lowest number of beam parts that gives a frequency comparable to that obtained from the Rayleigh formula. The obtained values are then compared to theoretical results based on the assumptions of the Bernoulli-Euler theory. These steps are repeated for the second type of mass representation in the same manner."

Keywords: finite element method, bernouilli eulertheory, structural analysis, vibration analysis, rayleigh quotient

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Authors: Minho Kwon, Jeonghee Lim, Yeongseok Jeong, Donghoon Shin, Kiyoung Kim

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Recently, global warming phenomenon has led to natural disasters caused by global environmental changes, and due to abnormal weather events, the frequency and intensity of heavy rain storm typhoons are increasing. Therefore, it is imperative to prepare for future heavy rain storms and typhoons. This study selects arbitrary target bridges and performs numerical analysis to evaluate the safety of bridge piers in the event that the water level changes. The numerical model is based on two-dimensional surface elements. Actual reinforced concrete was simulated by modeling concrete to include reinforcements, and a contact boundary model was applied between the ground and the concrete. The water level applied to the piers was considered at 18 levels between 7.5 m and 16.1 m. The elastic modulus, compressive strength, tensile strength, and yield strength of the reinforced concrete were calculated using 250 random combinations and numerical analysis was carried out for each water level. In the results of analysis, the bridge exceeded the stated limit at 15.0 m. At the maximum water level of 16.1m, the concrete’s failure rate was 35.2%, but the probability that the reinforcement would fail was 61.2%.

Keywords: Monte-Carlo method, pier, water level change, limit state

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Authors: Sophie Lemoussu, Jean-Charles Chaudemar, Robertus A. Vingerhoeds

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Many innovative projects exist in the field of aeronautics, each addressing specific areas so to reduce weight, increase autonomy, reduction of CO2, etc. In many cases, such innovative developments are being carried out by very small enterprises (VSE’s) or small and medium sized-enterprises (SME’s). A good example concerns airships that are being studied as a real alternative to passenger and cargo transportation. Today, no international regulations propose a precise and sufficiently detailed framework for the development and certification of airships. The absence of such a regulatory framework requires a very close contact with regulatory instances. However, VSE’s/SME’s do not always have sufficient resources and internal knowledge to handle this complexity and to discuss these issues. This poses an additional challenge for those VSE’s/SME’s, in particular those that have system integration responsibilities and that must provide all the necessary evidence to demonstrate their ability to design, produce, and operate airships with the expected level of safety and reliability. The main objective of this research is to provide a methodological framework enabling VSE’s/SME’s with limited resources to organize the development of airships while taking into account the constraints of safety, cost, time and performance. This paper proposes to provide a contribution to this problematic by proposing a Model-Based Systems Engineering approach. Through a comprehensive process modeling approach applied to the development processes, the regulatory constraints, existing best practices, etc., a good image can be obtained as to the process landscape that may influence the development of airships. To this effect, not only the necessary regulatory information is taken on board, also other international standards and norms on systems engineering and project management are being modeled and taken into account. In a next step, the model can be used for analysis of the specific situation for given developments, derive critical paths for the development, identify eventual conflicting aspects between the norms, standards, and regulatory expectations, or also identify those areas where not enough information is available. Once critical paths are known, optimization approaches can be used and decision support techniques can be applied so to better support VSE’s/SME’s in their innovative developments. This paper reports on the adopted modeling approach, the retained modeling languages, and how they all fit together.

Keywords: aeronautics, certification, process modeling, project management, regulation, SME, systems engineering, VSE

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Authors: Mohammad Tahir Yousafzai, Amna Rehana Siddiqui, Naveed Zafar Janjua

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We assessed the frequency and predictors of sharp injuries (SIs) among health care workers (HCWs) at first level care facilities (FLCF) in rural Pakistan. HCWs working at public clinic (PC), privately owned licensed practitioners’ clinic (LPC) and non-licensed practitioners’ clinic (NLC) were interviewed on universal precautions (UPs) and constructs of health belief model (HBM) to assess their association with SIs through negative-binomial regression. From 365 clinics, 485 HCWs were interviewed. Overall annual rate of Sis was 192/100 HCWs/year; 78/100 HCWs among licensed prescribers, 191/100 HCWs among non-licensed prescribers, 248/100 HCWs among qualified assistants, and 321/100 HCWs among non-qualified assistants. Increasing knowledge score about bloodborne pathogens (BBPs) transmission (rate-ratio (RR): 0.93; 95%CI: 0.89–0.96), fewer years of work experience, being a non-licensed prescriber (RR: 2.02; 95%CI: 1.36–2.98) licensed (RR: 2.86; 9%CI: 1.81–4.51) or non-licensed assistant (RR: 2.78; 95%CI: 1.72–4.47) compared to a licensed prescriber, perceived barriers (RR: 1.06;95%CI: 1.03–1.08), and compliance with UPs scores (RR: 0.93; 95%CI: 0.87–0.97) were significant predictors of SIs. Improved knowledge about BBPs, compliance with UPs and reduced barriers to follow UPs could reduce SIs to HCWs.

Keywords: health belief model, sharp injuries, needle stick injuries, healthcare workers

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Authors: Nishita Jaiswal, Apoorv Mohan Satpute

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The increasing demand for efficient, cost-effective motor control systems in the automotive industry has driven the need for advanced, highly optimized control algorithms. Field-Oriented Control (FOC) has established itself as the leading approach for motor control, offering precise and dynamic regulation of torque, speed, and position. However, as energy efficiency becomes more critical in modern applications, implementing FOC on low-power, cost-sensitive microcontrollers pose significant challenges due to the limited availability of computational and hardware resources. Currently, most solutions rely on high-performance 32-bit microcontrollers or Application-Specific Integrated Circuits (ASICs) equipped with Floating Point Units (FPUs) and Hardware Accelerated Units (HAUs). These advanced platforms enable rapid computation and simplify the execution of complex control algorithms like FOC. However, these benefits come at the expense of higher costs, increased power consumption, and added system complexity. These drawbacks limit their suitability for embedded systems with strict power and budget constraints, where achieving energy and execution efficiency without compromising performance is essential. In this paper, we present an alternative approach that utilizes optimized data representation and computation techniques on a 16-bit microcontroller without FPUs or HAUs. By carefully optimizing data point formats and employing fixed-point arithmetic, we demonstrate how the precision and computational efficiency required for FOC can be maintained in resource-constrained environments. This approach eliminates the overhead performance associated with floating-point operations and hardware acceleration, providing a more practical solution in terms of cost, scalability and improved execution time efficiency, allowing faster response in motor control applications. Furthermore, it enhances system design flexibility, making it particularly well-suited for applications that demand stringent control over power consumption and costs.

Keywords: field-oriented control, fixed-point arithmetic, floating point unit, hardware accelerator unit, motor control systems

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Authors: Kairat Uteulin, Serik Mukhambetzhanov, Izbasar Rakhimbaiev

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The effects of varying concentrations of growth regulators including 2, 4-D (2,4-Dichlorophenoxyacetic acid), BAP (6-benzylaminopurine), IAA (indole-3-acetic acid) and Kin (kinetin) was investigated for primary callus induction, embryogenic callus formation and regeneration of two elite Taraxacum kok-saghyz (TKS) lines, TKS1 and TKS2. Mature seeds were used as explants for primary callus induction. Different concentrations of 2, 4-D were investigated to study its effect on callus induction and callus growth frequency (CGF). Compact, whitish, healthy and fluffy calli were induced in TKS1 and TKS2 in MS medium supplemented with 5 mg/l and 4 mg/l 2, 4-D respectively. The calli produced were subjected to somatic embryogenesis and regeneration studies. For this purpose, MS Medium was supplemented with different concentrations and combinations of plant growth regulators like IAA and BAP. Maximum embryogenic callus formation was observed in MS medium supplemented with 0.1 mg/l IAA in combination with 1.5 mg/l BAP and it resulted in 73.51% and 62.33% embryogenic callus formation in TKS1 and TKS2 respectively. These optimum concentrations of IAA and BAP were further experimented with different concentrations of Kin for efficient regeneration and it was observed that 1 mg/l Kin was optimum for this purpose. Such studies help in understanding the response of TKS to tissue culture conditions and ultimately promise in improving yield by employing various biotechnological techniques.

Keywords: taraxacum kok-saghyz Rodin, callus, somatic embryogenesis

Procedia PDF Downloads 324

Authors: Mulata Haile Nega, Derebew Fikadu Berhe, Vera Ribeiro Marques

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There is no epidemiologic data on this gene polymorphism in several countries. Therefore, this study aimed to assess the genotype and allele frequencies of the gene variant in three countries. This study involved healthy individuals from Colombia, Mozambique, and Portugal. Genomic DNA was isolated from blood samples using the Qiamp DNA Extraction Kit (Qiagen). The isolated DNA was genotyped using Polymerase Chain Reaction (PCR) - Restriction Fragment Length Polymorphism. Microstat and GraphPad quick cal software were used for the Chi-square test and evaluation of Hardy-Weinberg equilibrium, respectively. A total of 181 individuals’ blood sample was analyzed. Overall, TT (74.0%) genotype was the highest, and CC (7.8%) was the lowest. Country wise genotypic frequencies were Colombia 47(70.2%) TT, 12(17.9%) TC and 8(11.9%) CC; Mozambique 47(88.7%) TT, 5(9.4%) TC, and 1(1.9%) CC; and Portugal 40(65.6%) TT, 16(26.2%) TC, and 5(8.2%) CC. The reference (T) allele was highest among Mozambicans (93.4%) compared to Colombians (79.1%) and Portuguese (78.7%). Mozambicans showed statistically significant genotypic and allelic frequency differences compared to Colombians (p<0.01) and Portuguese (p <0.01). Overall and country-wise, the CC genotype was less frequent and relatively high for Colombians and Portuguese populations. This finding may imply statins risk-benefit variability associated with CC genotype among these populations that needs further understanding.

Keywords: c.521T>C, polymorphism, SLCO1B1, SNP, statins

Procedia PDF Downloads 131

Authors: B. Soni, S. Biswas

Abstract:

Metal foams of Al find diverse applications in several industrial sectors such as in automotive and sports equipment industry as impact, acoustic and vibration absorbers, the aerospace industry as structural components in turbines and spatial cones, in the naval industry as low frequency vibration absorbers, and in construction industry as sound barriers inside tunnels, as fire proof materials and structure protection systems against explosions and even in heat exchangers, orthopedic components, and decorative items. Here, we report on the development of Al foams by a low cost and convenient technique of salt replication method with efficient control over size, geometry and distribution of the pores. Sodium bicarbonate was used as the foaming agent to form the porous refractory salt pattern. The mixed refractory salt slurry was microwave dried followed by sintering for selected time periods. Molten Al was infiltrated into the salt pattern in an inert atmosphere at a pressure of 2 bars. The final products were obtained by leaching out the refractory salt pattern. Mechanical properties of the derived samples were studied with a universal testing machine. The results were analyzed in correlation with their microstructural features evaluated with a scanning electron microscope (SEM).

Keywords: metal foam, Al, salt replication method, mechanical properties, SEM

Procedia PDF Downloads 351

Authors: Marco F. Benaglia, Mei H. Chen, Kune M. Tsai, Chia H. Hung

Abstract:

As societal and family structures, consumer dietary habits, and awareness about food safety and quality continue to evolve in most developed countries, the demand for refrigerated and frozen foods has been growing, and the issues related to their preservation have gained increasing attention. A well-established cold chain logistics system is essential to avoid any temperature abuse; therefore, assessing potential disruptions in the operational processes of cold chain logistics centers becomes pivotal. This study preliminarily employs HACCP to find disruption factors in cold chain logistics centers that may cause temperature abuse. Then, concept mapping is applied: selected experts engage in brainstorming sessions to identify any further factors. The panel consists of ten experts, including four from logistics and home delivery, two from retail distribution, one from the food industry, two from low-temperature logistics centers, and one from the freight industry. Disruptions include equipment-related aspects, human factors, management aspects, and process-related considerations. The areas of observation encompass freezer rooms, refrigerated storage areas, loading docks, sorting areas, and vehicle parking zones. The experts also categorize the disruption factors based on perceived similarities and build a similarity matrix. Each factor is evaluated for its impact, frequency, and investment importance. Next, multiple scale analysis, cluster analysis, and other methods are used to analyze these factors. Simultaneously, key disruption factors are identified based on their impact and frequency, and, subsequently, the factors that companies prioritize and are willing to invest in are determined by assessing investors’ risk aversion behavior. Finally, Cumulative Prospect Theory (CPT) is applied to verify the risk patterns. 66 disruption factors are found and categorized into six clusters: (1) "Inappropriate Use and Maintenance of Hardware and Software Facilities", (2) "Inadequate Management and Operational Negligence", (3) "Product Characteristics Affecting Quality and Inappropriate Packaging", (4) "Poor Control of Operation Timing and Missing Distribution Processing", (5) "Inadequate Planning for Peak Periods and Poor Process Planning", and (6) "Insufficient Cold Chain Awareness and Inadequate Training of Personnel". This study also identifies five critical factors in the operational processes of cold chain logistics centers: "Lack of Personnel’s Awareness Regarding Cold Chain Quality", "Personnel Not Following Standard Operating Procedures", "Personnel’s Operational Negligence", "Management’s Inadequacy", and "Lack of Personnel’s Knowledge About Cold Chain". The findings show that cold chain operators prioritize prevention and improvement efforts in the "Inappropriate Use and Maintenance of Hardware and Software Facilities" cluster, particularly focusing on the factors of "Temperature Setting Errors" and "Management’s Inadequacy". However, through the application of CPT theory, this study reveals that companies are not usually willing to invest in the improvement of factors related to the "Inappropriate Use and Maintenance of Hardware and Software Facilities" cluster due to its low occurrence likelihood, but they acknowledge the severity of the consequences if it does occur. Hence, the main implication is that the key disruption factors in cold chain logistics centers’ processes are associated with personnel issues; therefore, comprehensive training, periodic audits, and the establishment of reasonable incentives and penalties for both new employees and managers may significantly reduce disruption issues.

Keywords: concept mapping, cold chain, HACCP, cumulative prospect theory

Procedia PDF Downloads 66

Authors: Raleigh Blasdell, Amanda M. Sharp Parker, Lauren Waldrop, Brigid Toney

Abstract:

It has been demonstrated that fictional media sources have persuasive effects on public beliefs; this study contributes to the social constructionist literature by conducting a content analysis of U.S. major motion pictures involving terrorism. Using the Unified Film Population Sampling Methodology, the top-grossing films were identified to examine the frequency and context of several constructs of terrorism, including terrorist demographics, type of terrorism, country of origin, organizational affiliation, crime typology, and victim demographics. Comparisons of these constructs, as depicted in the films, were then made with the extant academic literature on terrorism. The data provide notable information regarding the representation of terrorism by the film industry, as well the discrepancies between the scholarly literature and depictions in popular films. The results indicate vast differences between fiction and reality, emphasizing a 'Middle Eastern Islamic male' terrorist stereotype. Using the theoretical foundation of social constructionism, the findings provide insight into how inaccurate depictions in film can influence society’s beliefs about terrorism and terrorists, which subsequently can translate into public support for legislation and policies that are often fueled by misinformation.

Keywords: film, media, social constructionism, terrorism

Procedia PDF Downloads 168

Authors: Jinhyun Ryu, Chengliang Xie, Nal Ae Yoon, Dong Hoon Lee, Gu Seob Roh, Hyun Joon Kim, Gyeong Jae Cho, Wan Sung Choi, Sang Soo Kang

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Type 2 diabetes is a heterogeneous group of metabolic disorders featured by a deficit in or loss of insulin activity to maintain normal glucose homeostasis. Mainly, it results from the compromised insulin secretion and/or reduced insulin activity. The frequency of type 2 diabetes (T2D) has been increased rapidly in recent decades with the increase in the trend of obesity due to life style and food habit. Obesity is considered to be the primary risk factor for the development of insulin resistance and thereby developing T2D. Traditionally naturally occurring fruits, vegetables etc. are being used to treat many pathogenic conditions. In this study, we tried to find out the effect of a popularly used vegetable in Bangladesh and several other Asian countries, ‘bitter melon’ on high fat diet induced T2D. To investigate the effect, we used 70% ethanol extract of bitter melon (BME) as dietary supplement with chow. BME was found to attenuate the high fat diet (HFD) induced body weight and total fat mass significantly. We also observed that BME reduced the insulin resistance induced by HFD effectively. Furthermore, dietary supplementation of BME was highly effective in increasing insulin sensitivity, and reducing the hepatic fat and obesity. These results indicate that BME could be effective to attenuate T2D and could be a preventive measure against T2D.

Keywords: bitter melon, obesity, type 2 diabetes, high fat diet

Procedia PDF Downloads 356