Search results for: relaxation-mode ferroelectric single crystal

Authors: Kumaresh Selvakumar, Man Young Kim

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In order to elaborate the main idea of investigating the flow physics inside the catalytic combustor, the characteristics of the catalytic surface reactions are analyzed by employing the CHEMKIN methodology with detailed gas and surface chemistries. The presence of a catalyst inside an engine enables complete combustion at lower temperatures which promotes desired chemical reactions. A single channel from the honeycomb monolith catalytic combustor is preferred to analyze the gas and surface reactions in the catalyst bed considering the fact that every channel in the honeycomb monolith behaves in similar fashion. The simplified approach with single catalyst channel using plug flow reactor can be used to predict the flow behavior inside the catalytic combustor. The hydrogen addition to the combustion reactants offers a way to light-off catalytic combustion of methane on platinum catalyst and aids to reduce the surface ignition temperature. Indeed, the hydrogen adsorption is higher on the uncovered Pt(s) surface sites because the sticking coefficient of hydrogen is larger than that of methane. The location of flame position in the catalyst bed is validated by igniting the methane fuel with the presence of hydrogen for corresponding multistep surface reactions.

Keywords: catalytic combustor, hydrogen adsorption, plug flow reactor, surface ignition temperature

Procedia PDF Downloads 353

Authors: Rama Debbarma, Debanjan Das

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The performance of multiple tuned mass dampers to mitigate the seismic vibration of structures considering real time history data is investigated in this paper. Three different real earthquake time history data like Kobe, Imperial Valley and Mammoth Lake are taken in the present study. The multiple tuned mass dampers (MTMD) are distributed at each storey. For comparative study, single tuned mass damper (STMD) is installed at top of the similar structure. This study is conducted for a fixed mass ratio (5%) and fixed damping ratio (5%) of structures. Numerical study is performed to evaluate the effectiveness of MTMDs and overall system performance. The displacement, acceleration, base shear and storey drift are obtained for both combined system (structure with MTMD and structure with STMD) for all earthquakes. The same responses are also obtained for structure without damper system. From obtained results, it is investigated that the MTMD configuration is more effective for controlling the seismic response of the primary system with compare to STMD configuration.

Keywords: Earthquake, multiple tuned mass dampers, single tuned mass damper, Time history.

Procedia PDF Downloads 273

Authors: Pejman Hosseinioun, Abolghasem Ghasempour, Elham Gholami, Hamed Sarbazi

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Considering the development in global semiconductor technology, it is anticipated that gadgets such as diodes and resonant transistor tunnels (RTD/RTT), Single electron transistors (SET) and quantum cellular automata (QCA) will substitute CMOS (Complementary Metallic Oxide Semiconductor) gadgets in many applications. Unfortunately, these new technologies cannot disembark the common Boolean logic efficiently and are only appropriate for liminal logic. Therefor there is no doubt that with the development of these new gadgets it is necessary to find new MacDraw technologies which are compatible with them. Resonant transistor tunnels (RTD/RTT) and circuit MacDraw with enhanced computing abilities are candida for accumulating Nano criterion in the future. Quantum cellular automata (QCA) are also advent Nano technological gadgets for electrical circuits. Advantages of these gadgets such as higher speed, smaller dimensions, and lower consumption loss are of great consideration. QCA are basic gadgets in manufacturing gates, fuses and memories. Regarding the complex Nano criterion physical entity, circuit designers can focus on logical and constructional design to decrease complication in MacDraw. Moreover Single electron technology (SET) is another noteworthy gadget considered in Nano technology. This article is a survey in future of Nano technology in digital MacDraw.

Keywords: nano technology, resonant transistor tunnels, quantum cellular automata, semiconductor

Procedia PDF Downloads 274

Authors: Joshua W. Edefo, Shafiul Azam, Murray D. Smith

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Introduction: In April 2022, the Welsh Government introduced the six goals for urgent and emergency care programs. One of these goals was to provide access to clinically safe alternatives, leading to the establishment of the Same Day Emergency Care (SDEC) program. The SDEC initiative aims to offer viable options that maintain patient safety while avoiding unnecessary hospital stays. The aim of the study is to determine the duration of patient stay in SDEC and compare it with that of Emergency department (ED) stay to ascertain if one of the objectives of SDEC is achieved. Methods: Patient stays and attendance datasets were constructed from Withybush SDEC and ED patient records. These records were provided by Hywel Dda University Health Board Informatics. Some hypothetical pathways were identified, notably SDEC visits involving a single attendance and ED visits then immediately transferred to SDEC. Descriptive statistics were used to summarise the data, and hypothesis tests for mean differences used the student t-test. Propensity scoring was employed to match a set of ED patient stays to SDEC patient stays which were then used to determine the average treatment effect (ATE) to compare durations of stay in SDEC with ED. Regression methods were used to model the natural logarithm of the duration of SDEC attendance, and the level of statistical significance was set to 0.05. Results: SDEC visits involving a single attendance (170 of 384; 44.3%) is the most frequently observed pathway with patient length of stay at 256 minutes (95%CI 237.4 - 275.1). The next most frequently observed pathway of patient stay was SDEC attendance after presenting to ED (80 of 384; 20.8%) and gave the length of stay of 440 minutes (95%CI 351.6 - 529.2). Time spent in this pathway significantly increased by 184 minutes (95%CI 118.0 - 250.2, support for no difference p<0.001) compared to the most seen pathway. When SDEC data were compared with ED, the estimate for the ATE from SDEC single attendance was -272 minutes (95%CI -334.1 - -210.5; p<0.001), while that of ED then SDEC pathway was -50.6 min (95%CI -182.7-81.5; p=0.453). Conclusion: When patients are admitted to SDEC and successfully discharged, their stays are significantly shorter, approximately 4.5 hours, compared to patients who spend their entire stay in the Emergency Department. That difference vanishes when the patient stay includes a period spent previously in ED before transfer to SDEC.

Keywords: attendance, emergency-department, patient-stay, same-day-emergency-care

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Authors: Ambuj Srivastava, Narender Singh

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This paper presents the effect of installation of cylindrical external store on the performance, stability, control and handling qualities of light transport category aircraft. A pair of long cylindrical store was installed symmetrically on either side of the fuselage (port and starboard) ahead of the wing and below the fuselage bottom surface running below pilot and co-pilot window. The cylindrical store was installed as hanging from aircraft surface through specially designed brackets. The adjoining structure was sufficiently reinforced for bearing aerodynamic loads. The length to diameter ratio of long cylindrical store was ~20. Based on academic studies and flow simulation analysis, a considerable detrimental effect on single engine second segment climb performance was found which was later validated through extensive flight testing exercise. The methodology of progressive flight envelope opening was adopted. The certification was sought from Regional airworthiness authorities and for according approval.

Keywords: second segment climb, maximum operating speed, cruise performance (single engine and twin engine), minimum control speed, and additional trim required

Procedia PDF Downloads 237

Authors: Gauthier Lefevre, Holger Kohlmann, Sebastien Saitzek, Rachel Desfeux, Adlane Sayede

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Hydrogen is a promising energy carrier, compatible with the sustainable energy concept. In this context, solid-state hydrogen-storage is the key challenge in developing hydrogen economy. The capability of absorption of large quantities of hydrogen makes intermetallic systems of particular interest. In this study, efforts have been devoted to the theoretical investigation of binary systems with constraints consideration. On the one hand, besides considering hydrogen-storage, a reinvestigation of crystal structures of the palladium-arsenic system shows, with experimental validations, that binary systems could still currently present new or unknown relevant structures. On the other hand, various binary Mg-based systems were theoretically scrutinized in order to find new interesting alloys for hydrogen storage. Taking the effect of pressure into account reveals a wide range of alternative structures, changing radically the stable compounds of studied binary systems. Similar constraints, induced by Pulsed Laser Deposition, have been applied to binary systems, and results are presented.

Keywords: binary systems, evolutionary algorithm, first principles study, pulsed laser deposition

Procedia PDF Downloads 275

Authors: E. A. Asabina, V. I. Pet'kov, P. A. Mayorov, A. V. Markin, N. N. Smirnova, A. M. Kovalskii, A. A. Usenko

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The purpose of this work was to synthesize and investigate phase formation, structure and thermophysical properties of the phosphates M_0.5+xM'_xZr_2–x(PO₄)₃ (M – Cd, Sr, Pb; M' – Mg, Co, Mn). The compounds were synthesized by sol-gel method. The results showed formation of limited solid solutions of NZP/NASICON type. The crystal structures of triple phosphates of the compositions MMg_0.5Zr_1.5(PO₄)₃ were refined by the Rietveld method using XRD data. Heat capacity (8–660 K) of the phosphates Pb_0.5+xMg_xZr_2-x(PO₄)₃ (x = 0, 0.5) was measured, and reversible polymorphic transitions were found at temperatures, close to the room temperature. The results of Rietveld structure refinement showed the polymorphism caused by disordering of lead cations in the cavities of NZP/NASICON structure. Thermal expansion (298−1073 K) of the phosphates MMg_0.5Zr_1.5(PO₄)₃ was studied by XRD method, and the compounds were found to belong to middle and low-expanding materials. Thermal diffusivity (298–573 K) of the ceramic samples of phosphates slightly decreased with temperature increasing. As was demonstrated, the studied phosphates are characterized by the better thermophysical characteristics than widespread fire-resistant materials, such as zirconia and etc.

Keywords: NASICON, NZP, phosphate, structure, synthesis, thermophysical properties

Procedia PDF Downloads 143

Authors: Dmitriy Syssoyev, Aslan Seitkamzin, Natalya Lim, Kamilla Mussina, Abduzhappar Gaipov, Dimitri Poddighe, Dinara Galiyeva

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Background: Data on the epidemiology of congenital heart defects (CHD) in Kazakhstan is scarce. Therefore, the aim of this study was to describe the incidence, prevalence and all-cause mortality of patients with CHD in Kazakhstan, using national large-scale registry data from the Unified National Electronic Healthcare System (UNEHS) for the period of 2014-2020. Methods: In this retrospective cohort study, the included data pertained to all patients diagnosed with CHD in Kazakhstan and registered in UNEHS between January 2014 and December 2020. CHD was defined based on International Classification of Diseases 10th Revision (ICD-10) codes Q20-Q26. Incidence, prevalence, and all-cause mortality rates were calculated per 100,000 population. Survival analysis was performed using Cox proportional hazards regression modeling and the Kaplan-Meier method. Results: In total, 66,512 patients were identified. Among them, 59,534 (89.5%) were diagnosed with a single CHD, while 6,978 (10.5%) had more than two CHDs. The median age at diagnosis was 0.08 years (interquartile range (IQR) 0.01 – 0.66) for people with multiple CHD types and 0.39 years (IQR 0.04 – 8.38) for those with a single CHD type. The most common CHD types were atrial septal defect (ASD) and ventricular septal defect (VSD), accounting for 25.8% and 21.2% of single CHD cases, respectively. The most common multiple types of CHD were ASD with VSD (23.4%), ASD with patent ductus arteriosus (PDA) (19.5%), and VSD with PDA (17.7%). The incidence rate of CHD decreased from 64.6 to 47.1 cases per 100,000 population among men and from 68.7 to 42.4 among women. The prevalence rose from 66.1 to 334.1 cases per 100,000 population among men and from 70.8 to 328.7 among women. Mortality rates showed a slight increase from 3.5 to 4.7 deaths per 100,000 in men and from 2.9 to 3.7 in women. Median follow-up was 5.21 years (IQR 2.47 – 11.69). Male sex (HR 1.60, 95% CI 1.45 - 1.77), having multiple CHDs (HR 2.45, 95% CI 2.01 - 2.97), and living in a rural area (HR 1.32, 95% CI 1.19 - 1.47) were associated with a higher risk of all-cause mortality. Conclusion: The incidence of CHD in Kazakhstan has shown a moderate decrease between 2014 and 2020, while prevalence and mortality have increased. Male sex, multiple CHD types, and rural residence were significantly associated with a higher risk of all-cause mortality.

Keywords: congenital heart defects (CHD), epidemiology, incidence, Kazakhstan, mortality, prevalence

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Authors: Afrouz Yousefi, Mohtada Sadrzadeh

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The widespread presence of poly- and perfluoroalkyl substances (PFAS) poses a significant concern due to their ability to accumulate in living organisms and their persistence in the environment, thanks to their robust carbon-fluorine (C-F) bonds, which require substantial energy to break (485 kJ/mol). The prevalence of toxic PFAS compounds can be highly detrimental to ecosystems, wildlife, and human health. Ongoing efforts are dedicated to investigating methods for fully breaking down and eliminating PFAS from the environment. Among the various techniques employed, advanced oxidation processes have shown promise in completely breaking down emerging contaminants in wastewater. However, the drawback lies in the relatively slow reaction rates of these processes and the substantial energy input required, which currently impedes their widespread commercial adoption. We developed a hybrid process, comprising electro-Fenton as an advanced oxidation process and membrane distillation, to simultaneously degrade organic PFAS pollutants and extract pure water from the mixture. In this study, environmentally persistent perfluorooctanoic acid (PFOA), as an emerging contaminant, was used to study the effectiveness of the electro-Fenton/membrane distillation hybrid system. The PFOA degradation studies were conducted in two modes: electro-Fenton and electro-Fenton coupled with membrane distillation. High-performance liquid chromatography with ultraviolet detection (HPLC-UV), ion-chromatography (measuring fluoride ion concentration), total organic carbon (TOC) decay, mineralization current efficiency (MCE), and specific energy consumption (SEC) were evaluated for a single EF and hybrid EF-MD processes. In contrast to a single EF reaction, TOC decay improved significantly in the EF-MD process. Overall, the MCE of hybrid processes surpassed 100% while it remained under 50% for a single EF reaction. Calculations of specific energy consumption (SEC) demonstrated a substantial decrease of nearly one-third in energy usage when integrating the EF reaction with the MD process.

Keywords: water treatment, PFAS, membrane distillation, electro-Fenton, advanced oxidation

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Authors: Susanna Asatryan

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The author will introduce a single module related to English teaching methodology for master course students getting specialization “A Foreign Language Teacher of High Schools And Professional Educational Institutions” of Yerevan Brusov State University of Languages and Social Sciences. The overall aim of the presentation is to introduce learning and teaching strategies within EXE Computer program for Mastery student-teachers of the University. The author will display the advantages of the use of this program. The learners interact with the teacher in the classroom as well as they are provided an opportunity for virtual domain to carry out their learning procedures in association with assessment and self-assessment. So they get integrated into blended learning. As this strategy is in its piloting stage, the author has elaborated a single module, embracing 3 main sections: -Teaching English vocabulary at high school, -Teaching English grammar at high school, and -Teaching English pronunciation at high school. The author will present the above mentioned topics with corresponding sections and subsections. The strong point is that preparing this module we have planned to display it on the blended learning landscape. So for this account working with EXE program is highly effective. As it allows the users to operate several tools for self-learning and self-testing/assessment. The author elaborated 3 single EXE files for each topic. Each file starts with the section’s subject-specific description: - Objectives and Pre-knowledge, followed by the theoretical part. The author associated and flavored her observations with appropriate samples of charts, drawings, diagrams, recordings, video-clips, photos, pictures, etc. to make learning process more effective and enjoyable. Before or after the article the author has downloaded a video clip, related to the current topic. EXE offers a wide range of tools to work out or prepare different activities and exercises for the learners: 'Interactive/non-interactive' and 'Textual/non-textual'. So with the use of these tools Multi-Select, Multi-Choice, Cloze, Drop-Down, Case Study, Gap-Filling, Matching and different other types of activities have been elaborated and submitted to the appropriate sections. The learners task is to prepare themselves for the coming module or seminar, related to teaching methodology of English vocabulary, grammar, and pronunciation. The point is that the teacher has an opportunity for face to face communication, as well as to connect with the learners through the Moodle, or as a single EXE file offer it to the learners for their self-study and self-assessment. As for the students’ feedback –EXE environment also makes it available.

Keywords: blended learning, EXE program, learning/teaching strategies, self-study/assessment, virtual domain,

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Authors: C. C. Chen, C. W. Hun, C. J. Wang, C. Y. Chen, J. S. Lin, K. J. Huang

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Cesium iodide (CsI) melt was injected into anodic aluminum oxide (AAO) template and was solidified to CsI column. The controllable AAO channel size (10~500 nm) can makes CsI column size from 10 to500 nm in diameter. In order to have a shorter light irradiate from each singe CsI column top to bottom the AAO template was coated a TiO2 nano-film. The TiO2 film acts a refraction film and makes X-ray has a shorter irradiation path in the CsI crystal making a stronger the photo-electron signal. When the incidence light irradiate from air (R=1.0) to CsI’s first surface (R=1.84) the first refraction happen, the first refraction continue into TiO2 film (R=2.88) and produces the low angle of the second refraction. Then the second refraction continue into AAO wall (R=1.78) and produces the third refraction after refractions between CsI and AAO wall (R=1.78) produce the fourth refraction. The incidence light after through CsI and TiO2 film refractions arrive to the CsI second surface. Therefore, the TiO2 film can has shorter refraction path of incidence light and increase the photo-electron conversion efficiency.

Keywords: cesium iodide, anodic aluminum oxide (AAO), TiO2, refraction, X-ray

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Authors: Yu Chen

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This paper investigates the influence of flaw on failure process of rock-like material under uniaxial compression. In laboratory, the uniaxial compression tests of intact specimens and a series of specimens within single flaw were conducted. The inclination angle of flaws includes 0°, 15°, 30°, 45°, 60°, 75° and 90°. Based on the laboratory tests, the corresponding models of numerical simulation were built and loaded in PFC2D. After analysing the crack initiation and failure modes, deformation field, and energy mechanism for both laboratory tests and numerical simulation, it can be concluded that the influence of flaws on the failure process is determined by its inclination. The characteristic stresses increase as flaw angle rising basically. The tensile cracks develop from gentle flaws (α ≤ 30°) and the shear cracks develop from other flaws. The propagation of cracks changes during failure process and the failure mode of a specimen corresponds to the orientation of the flaw. A flaw has significant influence on the transverse deformation field at the middle of the specimen, except the 75° and 90° flaw sample. The input energy, strain energy and dissipation energy of specimens show approximate increase trends with flaw angle rising and it presents large difference on the energy distribution.

Keywords: failure pattern, particle deformation field, energy mechanism, PFC

Procedia PDF Downloads 215

Authors: Taylor Kolody, Farkhund Iqbal, Rabia Batool, Benjamin Fung, Mohammed Hussaeni, Saiqa Aleem

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The rising threat of climate change has led to an increase in public awareness and care about our collective and individual environmental impact. A key component of this impact is our use of cars and other polluting forms of transportation, but it is often difficult for an individual to know how severe this impact is. While there are applications that offer this feedback, they require manual entry of what transportation mode was used for a given trip, which can be burdensome. In order to alleviate this shortcoming, a data from the 2016 TRIPlab datasets has been used to train a variety of machine learning models to automatically recognize the mode of transportation. The accuracy of 89.6% is achieved using single deep neural network model with Gated Recurrent Unit (GRU) architecture applied directly to trip data points over 4 primary classes, namely walking, public transit, car, and bike. These results are comparable in accuracy to results achieved by others using ensemble methods and require far less computation when classifying new trips. The lack of trip context data, e.g., bus routes, bike paths, etc., and the need for only a single set of weights make this an appropriate methodology for applications hoping to reach a broad demographic and have responsive feedback.

Keywords: classification, gated recurrent unit, recurrent neural network, transportation

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Authors: Jay P. Sipani, Riki H. Patel, Trushit Upadhyaya

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Today there is a demand to monitor environmental factors almost in all research institutes and industries and even for domestic uses. The analog data measurement requires manual effort to note readings, and there may be a possibility of human error. Such type of systems fails to provide and store precise values of parameters with high accuracy. Analog systems are having drawback of storage/memory. Therefore, there is a requirement of a smart system which is fully automated, accurate and capable enough to monitor all the environmental parameters with utmost possible accuracy. Besides, it should be cost-effective as well as portable too. This paper represents the Wireless Sensor (WS) data communication using DHT11, Arduino, SIM900A GSM module, a mobile device and Liquid Crystal Display (LCD). Experimental setup includes the heating arrangement of DHT11 and transmission of its data using Arduino and SIM900A GSM shield. The mobile device receives the data using Arduino, GSM shield and displays it on LCD too. Heating arrangement is used to heat and cool the temperature sensor to study its characteristics.

Keywords: wireless communication, Arduino, DHT11, LCD, SIM900A GSM module, mobile phone SMS

Procedia PDF Downloads 285

Authors: Faisal O. Al-Otaibi, Arthur T. Tucker, Richard M. Langford, Stuart Ratcliffe, Atholl Johnston, Terry D. Lee, Kenneth B. Kirby, Chandan A. Alam

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The Transdermal Delivery System (TDS®) is a proprietary liquid formulation that can be applied to intact skin via a metered pump spray to facilitate drug delivery to the circulation. The aim of this study was to assess the ability of the TDS preparation to deliver diazepam systemically, and to characterize the pharmacokinetic profile of the drug in healthy adult subjects. We conducted a randomized, single-dose, two-period, crossover phase I (pharmacokinetic) comparative study in twelve healthy volunteers. All volunteers received both 10 mg TDS-diazepam topically to the upper chest and 10 mg of the rectal diazepam preparation (Diastat®, 10 mg diazepam gel), with a minimum washout of 14 days between dosing episodes. Both formulations were well tolerated in all volunteers. Following topical application of TDS-diazepam, the mean AUC0-72h was 1241 ng/mL.h and the Cmax 34 ng/mL. The values for rectal Diastat were 4109 ng/mL.h and 300 ng/mL respectively. This proof of concept study demonstrates that the TDS preparation successfully delivered diazepam systemically to adults. As expected, the concentration of diazepam following the TDS application was lower and not bioequivalent to rectal gel. Future development of this unique system is required.

Keywords: transdermal delivery system, diazepam, seizure, bioequivalence, pharmacokinetic

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Authors: Christine S. Veviani

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By observing the Brazilian labor reality, considered as degrading and oppressive, as well as responsible for creating obstacles to rights, this paper is aimed at demonstrating the obligatoriness of complying with the Constitution, as an effective instrument of the Democratic and Social State of Law established in the country since 1988, which identifies and determines the recognition of a single type of citizenship, as representation of equality, social inclusion and human dignity. To achieve this purpose, that is, to awake to a new culture focused on human respect / fundamental rights engraved in the Brazilian Constitution, doctrinal works, case law and labor courts (how they work) will be used as methodology. Thus, by concluding that there is a need for a change in behavior, by employers, intended to respect the Constitution, especially with regard to the concept and citizenship content if an attempt is made to achieve as a result few steps effectiveness of fundamental social rights protective of the Brazilian working class. Thus, by analyzing the Brazilian labor reality, the result is the employers' denial of full and single citizenship of workers, whose effects are directly related to the violation of rights, which leads to the conclusion that there is a need for a change in the behavior regarding the respect for the Constitution, especially concerning the effectiveness of fundamental social rights, which protect the working class in Brazil.

Keywords: employment relationships, opposing citizenships, constitutionalism, capitalism

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Authors: Abass Braimah, Maha Hussein Abdallah

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The global ascendancy of terrorist attacks on building infrastructure with economic and heritage significance has increased awareness of the possibility of terrorism in Canada. Many structures in Canada that are at risk of terrorist attacks include government buildings, built many years ago of historic stone masonry construction. Although many researchers are investigating ways to retrofit masonry stone buildings to mitigate the effect of blast loadings, lack of knowledge on the dynamic behavior of historic stone masonry structures under blast loads makes it difficult to ascertain the effectiveness of the retrofitting techniques. This paper presents a review of open-source literature for the experimental and numerical stone masonry structures under blast loads. This review yielded very little information of the response of the historic stone masonry structures under blast loads. Thus, a comprehensive study is needed to understand the blast load effects on historic stone masonry buildings. The out-of-plane response of historic masonry structures to blast loads is investigated by using single-degree-of-freedom analysis. This approach presents equations that can be used effectively in the analysis of historic masonry walls to out-of-plane blast loading.

Keywords: blast loads, historical buildings, masonry structure, single-degree-of-freedom analysis

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Authors: Raka Aldy Nugraha, Kiwah Andanni, Aditya Indra Pratama, Aswin Guntara

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Background: Torus palatinus is a bony protuberance in the hard palate. Sex and race are considered as influencing factors for the development of torus palatinus. Hence, the objective of this study was to determine the prevalence and characteristics of torus palatinus and its correlation with sex and ethnicity among Western Indonesian Population. Methods: We conducted a descriptive and analytical study employing cross-sectional design in 274 new students of Universitas Indonesia. Data were collected by using consecutive sampling method through questionnaire-filling and direct oral examination. Subject with racial background other than indigenous Indonesian Mongol were excluded from this study. Data were statistically analyzed using chi square test for categorical variables whereas logistic regression model was employed to assess the correlation between variables of interest with prevalence of torus palatinus. Results: Torus palatinus were found in 212 subjects (77.4%), mostly small in size (< 3 mm) and single in number, with percentage of 50.5% and 90.6%, respectively. The prevalence of torus palatinus were significantly higher in women (OR 2.88; 95% CI: 1.53-5.39; p = 0.001), dominated by medium-sized and single tori. There was no significant correlation between ethnicity and the occurrence of torus palatinus among Western Indonesian population. Conclusion: Torus palatinus was prevalent among Western Indonesian population. It showed significant positive correlation with sex, but not with ethnicity.

Keywords: characteristic, ethnicity, Indonesia, mongoloid, prevalence, sex, Torus palatinus

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Authors: Nouri Sabrina, Benzeghiba Mohamed, Ghezal Abderrahmane

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Numerical parametric study is conducted to study the effects of ampoule rotation on the flows and the dopant segregation in vertical Bridgman (VB) crystal growth. Calculations were performed in unsteady state. The extended Darcy model, which includes the time derivative and Coriolis terms, has been employed in the momentum equation. It was found that the convection, and dopant segregation can be affected significantly by ampoule rotation, and the effect is similar to that by an axial magnetic field. Ampoule rotation decreases the intensity of convection and stretches the flow cell axially. When the convection is weak, the flow can be suppressed almost completely by moderate ampoule rotation and the dopant segregation becomes diffusion-controlled. For stronger convection, the elongated flow cell by ampoule rotation may bring dopant mixing into the bulk melt reducing axial segregation at the early stage of the growth. However, if the cellular flow cannot be suppressed completely, ampoule rotation may induce larger radial segregation due to poor mixing.

Keywords: numerical simulation, heat and mass transfer, vertical solidification, chemical segregation

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Authors: Muhammad Maqsood, Yasir Nawab, Syed Talha Ali Hamdani

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Stretchable fabrics have diverse applications ranging from casual apparel to performance sportswear and compression therapy. Compression therapy is the universally accepted treatment for the management of hypertrophic scarring after severe burns. Mostly stretchable knitted fabrics are used in compression therapy but in the recent past, some studies have also been found on bi-stretch woven fabrics being used as compression garments as they also have been found quite effective in the treatment of oedema. Therefore, the objective of the present study is to compare the compression properties of stretchable knitted and bi-stretch woven fabrics for compression garments. For this purpose four woven structures and four knitted structures were produced having the same areal density and their compression, comfort and mechanical properties were compared before and after 5, 10 and 15 washes. Four knitted structures used were single jersey, single locaste, plain pique and the honeycomb, whereas four woven structures produced were 1/1 plain, 2/1 twill, 3/1 twill and 4/1 twill. The compression properties of the produced samples were tested by using kikuhime pressure sensor and it was found that bi-stretch woven fabrics possessed better compression properties before and after washes and retain their durability after repeated use, whereas knitted stretchable fabrics lost their compression ability after repeated use and the required sub garment pressure of the knitted structures after 15 washes was almost half to that of woven bi-stretch fabrics.

Keywords: compression garments, knitted structures, medical textiles, woven bi-stretch

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Authors: Gulcan Sahal, Isil Seyis Bilkay

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Candida species which often exist as commensal microorganisms in healthy individuals are major causes of important infections, especially in AIDS and immunocompromised patients, by means of their biofilm formation abilities. Therefore, in this study, determination of biofilm formation in different clinical strains of Candida species, investigation of strong biofilm forming Candida strains, examination of clinical information of each strong and weak biofilm forming Candida strains and investigation of some plant substances’ effects on biofilm formation of strong biofilm forming strains were aimed. In this respect, biofilm formation of Candida strains was analyzed via crystal violet binding assay. According to our results, biofilm levels of strains belong to different Candida species were different from each other. Additionally, it is also found that some plant substances effect biofilm formation. All these results indicate that, as well as C. albicans strains, other non-albicans Candida species also emerge as causative agents of infections and have biofilm formation abilities. In addition, usage of some plant substances in different concentrations may provide a new treatment against biofilm related Candida infections.

Keywords: anti-biofilm, biofilm formation, Candida species, biosystems engineering

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Authors: K. Arroudj, M. Lanez, M. N. Oudjit

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The introduction of siliceous mineral additions in cement production allows, in addition to the ecological and economic gain, improvement of concrete performance. This improvement is mainly due to the fixing of Portlandite, released during the hydration of cement, by fine siliceous, forming denser calcium silicate hydrates and therefore a more compact cementitious matrix. This research is part of the valuation of the Dune Sand (DS) in the cement industry in Algeria. The high silica content of DS motivated us to study its effect, at ground state, on the properties of mortars in fresh and hardened state. For this purpose, cement pastes and mortars based on ground dune sand (fine quartz) has been analyzed with a replacement to cement of 15%, 20% and 25%. This substitution has reduced the amount of heat of hydration and avoids any risk of initial cracking. In addition, the grinding of the dune sand provides amorphous thin populations adsorbed at the surface of the crystal particles of quartz. Which gives to ground quartz pozzolanic character. This character results an improvement of mechanical strength of mortar (66 MPa in the presence of 25% of ground quartz).

Keywords: mineralogical structure, pozzolanic reactivity, Quartz, mechanical strength

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Authors: Aftab Khan, Ashfaq Khan

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The research paper focuses on an interesting challenge faced in Blind Image Deblurring (BID). It relates to the estimation of arbitrarily shaped or non-parametric Point Spread Functions (PSFs) of motion blur caused by camera handshake. These PSFs exhibit much more complex shapes than their parametric counterparts and deblurring in this case requires intricate ways to estimate the blur and effectively remove it. This research work introduces a novel blind deblurring scheme visualized for deblurring images corrupted by arbitrarily shaped PSFs. It is based on Genetic Algorithm (GA) and utilises the Blind/Reference-less Image Spatial QUality Evaluator (BRISQUE) measure as the fitness function for arbitrarily shaped PSF estimation. The proposed BID scheme has been compared with other single image motion deblurring schemes as benchmark. Validation has been carried out on various blurred images. Results of both benchmark and real images are presented. Non-reference image quality measures were used to quantify the deblurring results. For benchmark images, the proposed BID scheme using BRISQUE converges in close vicinity of the original blurring functions.

Keywords: blind deconvolution, blind image deblurring, genetic algorithm, image restoration, image quality measures

Procedia PDF Downloads 447

Authors: Nurul Huda Baharuddin, Nik Meriam Nik Sulaiman, Mohammed Kheireddine Aroua

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The effects of pH, polymer concentration, and metal ions feed concentration for four selected heavy metals Zn (II), Pb (II), Cr (III) and Cr (VI) were tested by using Polymer Enhanced Ultrafiltration (PEUF). An alternative biopolymer namely unmodified starch is proposed as a binding reagent in consequences, as compared to commonly used water-soluble polymers namely polyethylene glycol (PEG) and polyethyleneimine (PEI) in the removal of selected four heavy metal ions. The speciation species profiles of four selected complexes ions namely Zn (II), Pb (II), Cr (III) and Cr (VI) and the present of hydroxides ions (OH-) in variously charged ions were investigated by available software at certain pH range. In corresponds to identify the potential of complexation behavior between metal ion-polymers, potentiometric titration studies were obtained at first before carried out experimental works. Experimental works were done using ultrafiltration systems obtained by laboratory ultrafiltration bench scale equipped with 10 kDa polysulfone hollow fiber membrane. Throughout the laboratory works, the rejection coefficient and permeate flux were found to be significantly affected by the main operating parameter, namely the effects of pH, polymer composition and metal ions concentrations. The interaction of complexation between two binding polymers namely unmodified starch and PEG were occurred due to physical attraction of metal ions to the polymer on the molecular surface with high possibility of chemical occurrence. However, these selected metal ions are mainly complexes by polymer functional groups whenever there is interaction with PEI polymer. For study of single metal ions solutions, Zn (II) ions' rejections approaching over 90% were obtained at pH 7 for each tested polymer. This behavior was similar to Pb (II), Cr (III) and Cr (VI); where the rejections were obtained at lower acidic pH and increased at neutral pH of 7. Different behavior was found by Cr (VI) ions where a high rejection was only achieved at acidic pH region with PEI. Polymer concentration and metal ions concentration are found to have a significant effect on rejections. For mixed metal ion solutions, the behavior of metal ion rejections was similar to single metal ion solutions for investigation on the effects of pH. Rejection values were high at pH 7 for Zn (II) pH 7 for Zn (II) and Cr (III) ions, corresponding to higher rejections with unmodified starch. Pb (II) ions obtained high rejections when tested with PEG whenever carried out in mixed metal ion solutions. High Cr (VI) ions' rejection was found with PEI in single and mixed metal ions solutions at neutral pH range. The influence of starch’s granule structure towards the rejections of these four selected metal ions is found to be attracted in a non-ionic manner. No significant effects on permeate flux were obtained when tested at different pH ranges, polymer concentrations and metal ions feed either by single or mixtures metal ions solutions. Canizares Model was employed as the theoretical model to predict permeate flux and metal ions retention on the study of heavy metal ions removal.

Keywords: polyethyleneimine, polyethylene glycol, polymer-enhanced ultrafiltration, unmodified starch

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Authors: Yu-Kuei Hsu, Ying-Chu Chen, Yan-Gu Lin

Abstract:

The hierarchical Cu2S nano structural film is successfully fabricated via an electroplated ZnO nanorod array as a template and subsequently chemical solution process for the growth of Cu2S in the application of surface-enhanced Raman scattering (SERS) detection. The as-grown Cu2S nano structures were thermally treated at temperature of 150-300 oC under nitrogen atmosphere to improve the crystal quality and unexpectedly induce the Cu nano particles on surface of Cu2S. The structure and composition of thermally treated Cu2S nano structures were carefully analyzed by SEM, XRD, XPS, and XAS. Using 4-aminothiophenol (4-ATP) as probing molecules, the SERS experiments showed that the thermally treated Cu2S nano structures exhibit excellent detecting performance, which could be used as active and cost-effective SERS substrate for ultra sensitive detecting. Additionally, this novel hierarchical SERS substrates show good reproducibility and a linear dependence between analyte concentrations and intensities, revealing the advantage of this method for easily scale-up production.

Keywords: cuprous sulfide, copper, nanostructures, surface-enhanced raman scattering

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Authors: Rahmathulla Noufal E.

Abstract:

Investigating the dynamic responses of high rise structures under the effect of siesmic ground motion is extremely important for the proper analysis and design of multitoried structures. Since the presence of infilled walls strongly influences the behaviour of frame systems in multistoried buildings, there is an increased need for developing guidelines for the analysis and design of infilled frames under the effect of dynamic loads for safe and proper design of buildings. In this manuscript, we evaluate the natural frequencies and natural periods of single bay single storey frames considering the effect of infill walls by using the Eigen value analysis and validating with SAP 2000 (free vibration analysis). Various parameters obtained from the diagonal strut model followed for the free vibration analysis is then compared with the Finite Element model, where infill is modeled as shell elements (four noded). We also evaluated the effect of various parameters on the natural periods of vibration obtained by free vibration analysis in SAP 2000 comparing them with those obtained by the empirical expressions presented in I.S. 1893(Part I)-2002.

Keywords: infilled frame, eigen value analysis, free vibration analysis, diagonal strut model, finite element model, SAP 2000, natural period

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Authors: Irnie Zakaria, W. A. N. W. Mohamed, W. H. Azmi

Abstract:

Thermal enhancement of a single mini channel in Proton Exchange Membrane Fuel Cell (PEMFC) cooling plate is numerically investigated. In this study, low concentration of Al2O3 in Water - Ethylene Glycol mixtures is used as coolant in mini channel of carbon graphite plate to mimic the PEMFC cooling plate. A steady and incompressible flow with constant heat flux is assumed in the channel of 1mm x 5mm x 100mm. Nano particle of Al2O3 used ranges from 0.1, 0.3 and 0.5 vol % concentration and then dispersed in 60:40 (water: Ethylene Glycol) mixture. The effect of different flow rates to fluid flow and heat transfer enhancement in Re number range of 20 to 140 was observed. The result showed that heat transfer coefficient was improved by 18.11%, 9.86% and 5.37% for 0.5, 0.3 and 0.1 vol % Al2O3 in 60:40 (water: EG) as compared to base fluid of 60:40 (water: EG). It is also showed that the higher vol % concentration of Al2O3 performed better in term of thermal enhancement but at the expense of higher pumping power required due to increase in pressure drop experienced. Maximum additional pumping power of 0.0012W was required for 0.5 vol % Al2O3 in 60:40 (water: EG) at Re number 140.

Keywords: heat transfer, mini channel, nanofluid, PEMFC

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Authors: Matthew Brady

Abstract:

Lack of affordable housing for individuals has the potential to create gaps in society, which result in thousands of people facing homelessness every year in some of the worlds most affluent cities. This paper examines strategies for providing a more economic living environment for single occupants. Focusing on comparisons of successful examples reducing homeless populations around the world, with an emphasis on social inclusion and community living. Practically exploring the architectural considerations of ensuring a suitable living environment for multiple single occupancy residents, as well as selecting the appropriate materials to ensure costs are kept to manageable level for investment from local governments. The aim of this paper is to make some practical recommendations for low cost communal living space, with particular reference to recycled shipping container homes on a potential unused site on the River Clyde in Glasgow. Ideally, the suggestions and recommendations put forward in this paper can be replicable or used for reference in other similar situations. The proposal explored in this paper is sensitive towards addressing people's standard of living and adapting homes to match may be one solution to reducing the number of people being evicted from unaffordable homes as the generally upward global trend for urbanization continues.

Keywords: affordable housing, community living, shipping container, urban regeneration

Procedia PDF Downloads 186

Authors: Anuj Pathare, Aleksandra Birn-Jeffery

Abstract:

Background: The Anterior Cruciate Ligament(ACL) helps stabilize the knee joint minimizing tibial anterior translation. Anterior Cruciate Ligament (ACL) injury is common in racquet sports and often occurs due to sudden acceleration, deceleration or changes of direction. This mechanism in badminton most commonly occurs during landing after an overhead stroke. Knee biomechanics during dynamic movements such as walking, running and stair negotiation, do not return to normal for more than a year after an ACL reconstruction. This change in the biomechanics may lead to re-injury whilst performing non-steady movements during sports, where these injuries are most prevalent. Aims: To compare if the knee kinetics and kinematics in ACL injury recovered athletes return to the same level as those from an uninjured cohort during standard movements used for clinical assessment and badminton shots. Objectives: The objectives of the study were to determine: Knee valgus during the single leg squat, vertical drop jump, net shot and drop shot; Degree of internal or external rotation during the single leg squat, vertical drop jump, net shot and drop shot; Maximum knee flexion during the single leg squat, vertical drop jump and net shot. Methods: This case-control study included 14 participants with three ACL injury recovered athletes and 11 uninjured participants. The participants performed various functional tasks including vertical drop jump, single leg squat; the forehand net shot and the forehand drop shot. The data was analysed using the two-way ANOVA test, and the reliability of the data was evaluated using the Intra Class Coefficient. Results: The data showed a significant decrease in the range of knee rotation in ACL injured participants as compared to the uninjured cohort (F₇,₅₅₆=2.37; p=0.021). There was also a decrease in the maximum knee flexion angles and an increase in knee valgus angles in ACL injured participants although they were not statistically significant. Conclusion: There was a significant decrease in the knee rotation angles in the ACL injured participants which could be a potential cause for re-injury in these athletes in the future. Although the results for decrease in maximum knee flexion angles and increase in knee valgus angles were not significant, this may be due to a limited sample of ACL injured participants; there is potential for it to be identified as a variable of interest in the rehabilitation of ACL injuries. These changes in the knee biomechanics could be vital in the rehabilitation of ACL injured athletes in the future, and an inclusion of sports based tasks, e.g., Net shot along with standard protocol movements for ACL assessment would provide a better measure of the rehabilitation of the athlete.

Keywords: ACL, biomechanics, knee injury, racquet sport

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Authors: Nouri Sabrina

Abstract:

Numerical parametric study is conducted to study the effects of ampoule rotation on the flows and the dopant segregation in Vertical Bridgman (VB) crystal growth. Calculations were performed in unsteady state. The extended darcy model, whıch includes the time derivative and coriolis terms, has been employed in the momentum equation. It is found that the convection, and dopant segregation can be affected significantly by ampoule rotation, and the effect is similar to that by an axial magnetıc field. Ampoule rotation decreases the intensity of convection and stretches the flow cell axıally. When the convectıon is weak, the flow can be suppressed almost completely by moderate ampoule rotation and the dopant segregation becomes diffusion-controlled. For stronger convection, the elongated flow cell by ampoule rotation may bring dopant mixing into the bulk melt reducing axial segregation at the early stage of the growth. However, if the cellular flow cannot be suppressed completely, ampoule rotation may induce larger radial segregation due to poor mixing.

Keywords: rotating vertical solidification, Finite Volume Method, heat and mass transfer, porous medium, phase change

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