Search results for: high school gifted pupils

Authors: S. Sadegzadeh, A. Mousavi

Abstract:

Temperature-dependent tunable photonic crystals have attracted widespread interest in recent years. In this research, transmission characteristics of a one-dimensional photonic crystal structure with a single defect have been studied. Here, we assume two different defect layers: InSb as a semiconducting layer and HgBa₂Ca₂Cu₃O₁₀ as a high-temperature superconducting layer. Both the defect layers have temperature-dependent refractive indexes. Two different types of dielectric materials (Si as a high-refractive index dielectric and MgF₂ as a low-refractive index dielectric) are used to construct the asymmetric structures (Si/MgF₂)^NInSb(Si/MgF₂)^N named S.I, and (Si/MgF₂)^NHgBa₂Ca₂Cu₃O₁₀(Si/MgF₂)^N named S.II. It is found that in response to the temperature changes, transmission peaks within the photonic band gap of the S.II structure, in contrast to S.I, show a small wavelength shift. Furthermore, the results show that under the same conditions, S.I structure generates an extra defect mode in the transmission spectra. Besides high efficiency transmission property of S.II structure, it can be concluded that the semiconductor-dielectric photonic crystals are more sensitive to temperature variation than superconductor types.

Keywords: defect modes, photonic crystals, semiconductor, superconductor, transmission

Procedia PDF Downloads 275

Authors: Bhawat Chiamjinnawat

Abstract:

The agri-food market transformation has implied market growth for the fruit industry in Thailand. This article focuses on analysis of farmer competence and farm resources which affect market strategies used by fruit farmers in Chanthaburi province of Thailand. The survey data were collected through the use of face-to-face interviews with structured questionnaires. This study identified 14 drivers related to farmer competence and farm resources of which some had significant effect on the decision to use either high-value markets or traditional markets. The results suggest that farmers who used high-value markets were better educated and they had longer experience and larger sized business. Identifying the important factors that match with the market transformation provides policy with opportunities to support the fruit farmers to increase their market power. Policies that promote business expansion of agricultural cooperatives and knowledge sharing among farmers are recommended to reduce limitations due to limited knowledge, low experience, and small business sizes.

Keywords: farmer competence, farm resources, fruit industry, high-value markets, Thailand

Procedia PDF Downloads 151

Authors: Mathinee Khongsatid, Phusit Phukamchanoad, Sakapas Saengchai

Abstract:

This research aims to study the democratic political socialization of the 5th and 6th Graders under the Authority of Dusit District Office, Bangkok by using stratified sampling for probability sampling and using purposive sampling for non-probability sampling to collect data toward the distribution of questionnaires to 300 respondents. This covers all of the schools under the authority of Dusit District Office. The researcher analyzed the data by using descriptive statistics which include arithmetic mean and standard deviation. The result shows that 5th and 6th graders under the authority of Dusit District Office, Bangkok, have displayed some characteristics following democratic political socialization both inside and outside classroom as well as outside school. However, the democratic political socialization in classroom through grouping and class participation is much more emphasized.

Keywords: democratic, political socialization, students grades 5-6, descriptive statistics

Procedia PDF Downloads 265

Authors: Yael Fisher

Abstract:

Little is known about perceived self-efficacy of public preschool teachers, their perception of preschool excellence, or the relations between the two. There were three purposes for this research: defining the professional self-efficacy of preschool teachers (PTSE); defining preschool teachers' perception of preschool excellence (PTPPE); and investigating the relationship between the two. Scales for PTSE and PTPPE were developed especially for this study. Public preschool teachers (N = 202) participated during the 2013 school year. Structural Equation Modeling was performed to test the fit between the research model and the obtained data. PTPSE scale (α = 0.91) was comprised of three subscales: pedagogy (α=0.84), organization (α = 0.85) and staff (α = 0.72). The PTPPE scale (α = 0.92) is also composed of three subscales: organization and pedagogy (α = 0.88), staff (α = 0.84) and parents (α = 0.83). The goodness of fit measures were RMSEA = 0.045, CFI = 0.97, NFI = 0.89, df = 173, χ²=242.94, p= .000, showing GFI = 1.4 (< 3) as a good fit. Understanding self-efficacy of preschool teachers, preschool could and should lead to better professional development (in-service training) of preschool teachers.

Keywords: self-efficacy, public pre schools, preschool excellence, SEM

Procedia PDF Downloads 111

Authors: Mei-Hui Liu

Abstract:

This paper reports the progression of language teachers’ learning to assess students’ speech act performance via online videos in a cross-tier professional growth community. This yearlong research project collected multiple data sources from several stakeholders, including 12 preservice and 4 inservice English as a foreign language (EFL) teachers, 4 English professionals, and 82 high school students. Data sources included surveys, (focus group) interviews, online reflection journals, online video-based assessment items/scores, and artifacts related to teacher professional learning. The major findings depicted the effectiveness of this proposed learning module on language teacher development in pragmatic assessment as well as its impact on student learning experience. All these teachers appreciated this professional learning experience which enhanced their knowledge in assessing students’ pragmalinguistic and sociopragmatic performance in an English speech act (i.e., making refusals). They learned how to design online video-based assessment items by attending to specific linguistic structures, semantic formula, and sociocultural issues. They further became aware of how to sharpen pragmatic instructional skills in the near future after putting theories into online assessment and related classroom practices. Additionally, data analysis revealed students’ achievement in and satisfaction with the designed online assessment. Yet, during the professional learning process most participating teachers encountered challenges in reaching a consensus on selecting appropriate video clips from available sources to present the sociocultural values in English-speaking refusal contexts. Also included was to construct test items which could testify the influence of interlanguage transfer on students’ pragmatic performance in various conversational scenarios. With pedagogical implications and research suggestions, this study adds to the increasing amount of research into integrating preservice and inservice EFL teacher education in pragmatic assessment and relevant instruction. Acknowledgment: This research project is sponsored by the Ministry of Science and Technology in the Republic of China under the grant number of MOST 106-2410-H-029-038.

Keywords: cross-tier professional development, inservice EFL teachers, pragmatic assessment, preservice EFL teachers, student learning experience

Procedia PDF Downloads 240

Authors: T. Ahilan, V. Aswin Adityan, S. Kailash

Abstract:

UAV’s are small remote operated or automated aerial surveillance systems without a human pilot aboard. UAV’s generally finds its use in military and special operation application, a recent growing trend in UAV’s finds its application in several civil and non military works such as inspection of power or pipelines. The objective of this paper is the augmentation of a UAV in order to replace the existing expensive sonar (sound navigation and ranging) based equipment amongst small scale fisherman, for whom access to sonar equipment are restricted due to limited economic resources. The surveillance equipment’s present in the UAV will relay data and GPS location onto a receiver on the fishing boat using RF signals, using which the location of the schools of fishes can be found. In addition to this, an emergency beacon system is present for rescue operations and drone recovery.

Keywords: UAV, Surveillance, RF signals, fishing, sonar, GPS, video stream, school of fish

Procedia PDF Downloads 445

Authors: Mark Christian Inductivo Siwa, Jesrelle Ormoc Bontuyan

Abstract:

This study was conducted in selected tertiary schools in selected universities in Asian countries such as Philippines, Thailand, and China, which are the top performing countries in Southeast Asian Games or SEA Games and Asian School Games (ASG), also known as the Youth SEA Games and Asian Games. The respondents of the study are sports administrators/directors and coaches in selected Southeast Asian countries such as Philippines, Thailand, and in Asia which is China. This study has generated a progressive sports operational model of Sports Leadership and Management in Selected Universities in Asia. This study utilized mixed-method research. It is a methodology for conducting research that involves collecting, analyzing and integrating quantitative (e.g., experiments, surveys) and qualitative (e.g., focus groups, interviews) research. This approach to research is used to provide integration for a better understanding of the research problem than either of each alone. This study particularly employed the explanatory sequential design of mixed methods, which involved two phases: the quantitative phase, which involves the collection and analysis of quantitative data, followed by the qualitative phase, which involves the collection and analysis of qualitative data. This study will prioritize the quantitative data and the findings will be followed up during the interpretation phase in the qualitative data of the study. The qualitative data help explain or build upon initial quantitative results. In phase I, the researcher began with the collection and analysis of the quantitative data. His investigation gave greater emphasis on the quantitative methods, particularly employed surveys with the coaches and sports directors of the three selected universities in Asia. In Phase II, the researcher subsequently collected and analyzed the qualitative data obtained through an interview with the sports directors to follow from or connect to the results of the quantitative phase. This study followed the data analysis spiral so that the researcher could follow – up or explain the quantitative results. The researcher engaged in the process of moving in analytic circles. Based on the school's mission and vision, the sports leadership and management consistently followed the key factors to take into account when leading the organization and managing the process in sports leadership and management when formulating objectives/goals, budget, equipment care and maintenance, facilities, training matrix, and consideration. Also, sports management demonstrates the need for development in terms of the upkeep and care of equipment as well as athlete funding. The development of goals or sports management goals, sports facilities and equipment, as well as improvements in demonstrating training and consideration, and incentives, should also include a maintenance plan. The study concluded with a progressive sports operational model that was created based on the result of the study.

Keywords: sports leadership and management, formulating objectives, budget, equipment care and maintenance, training, consideration, incentives, progressive sports operational model

Procedia PDF Downloads 76

Authors: Ruthanne Tobin

Abstract:

As our data-driven, cloud-based, knowledge-centric lives become ever more global, mobile, and digital, educational systems everywhere are struggling to keep pace. Schools need to prepare students to become critical-thinking, tech-savvy, life-long learners who are engaged and adaptable enough to find their unique calling in a post-industrial world of work. Recognizing that no nation can afford poor achievement or high dropout rates without jeopardizing its social and economic future, the thirty-two nations of the OECD are launching initiatives to redesign schools, generally under the banner of Personalized Learning or 21st Century Learning. Their intention is to transform education by situating students as co-enquirers and co-contributors with their teachers of what, when, and how learning happens for each individual. In this focused review of the 2007-2017 literature on personalized learning, the author sought answers to two main questions: “What are the theoretical frameworks that guide personalized learning?” and “What is the conceptual understanding of the model?” Ultimately, the review reveals that, although the research area is overly theorized and under-substantiated, it does provide a significant body of knowledge about this potentially transformative educational restructuring. For example, it addresses the following questions: a) What components comprise a PL model? b) How are teachers facilitating agency (voice & choice) in their students? c) What kinds of systems, processes and procedures are being used to guide the innovation? d) How is learning organized, monitored and assessed? e) What role do inquiry based models play? f) How do teachers integrate the three types of knowledge: Content, pedagogical and technological? g) Which kinds of forces enable, and which impede, personalizing learning? h) What is the nature of the collaboration among teachers? i) How do teachers co-regulate differentiated tasks? One finding of the review shows that while technology can dramatically expand access to information, expectations of its impact on teaching and learning are often disappointing unless the technologies are paired with excellent pedagogies in order to address students’ needs, interests and aspirations. This literature review fills a significant gap in this emerging field of research, as it serves to increase conceptual clarity that has hampered both the theorizing and the classroom implementation of a personalized learning model.

Keywords: curriculum change, educational innovation, personalized learning, school reform

Procedia PDF Downloads 204

Authors: Ruquan You, Haiwang Li, Zhi Tao

Abstract:

A time-resolved particle image velocimetry (PIV) system is developed to investigate the boundary layer flow with the effect of rotating Coriolis and buoyancy force. This time-resolved PIV system consists of a 10 Watts continuous laser diode and a high-speed camera. The laser diode is able to provide a less than 1mm thickness sheet light, and the high-speed camera can capture the 6400 frames per second with 1024×1024 pixels. The whole laser and the camera are fixed on the rotating facility with 1 radius meters and up to 500 revolutions per minute, which can measure the boundary flow velocity in the rotating channel with and without ribs directly at rotating conditions. To investigate the effect of buoyancy force, transparent heater glasses are used to provide the constant thermal heat flux, and then the density differences are generated near the channel wall, and the buoyancy force can be simulated when the channel is rotating. Due to the high temporal and spatial resolution of the system, the proper orthogonal decomposition (POD) can be developed to analyze the characteristic of the turbulent boundary layer flow at rotating conditions. With this rotating facility and PIV system, the velocity profile, Reynolds shear stress, spatial and temporal correlation, and the POD modes of the turbulent boundary layer flow can be discussed.

Keywords: rotating facility, PIV, boundary layer flow, spatial and temporal resolution

Procedia PDF Downloads 167

Authors: Muhammad Bilal, Zhongfeng Qiu

Abstract:

Aerosols, suspended particles in the atmosphere, play an important role in the earth energy budget, climate change, degradation of atmospheric visibility, urban air quality, and human health. To fully understand aerosol effects, retrieval of aerosol optical properties such as aerosol optical depth (AOD) at high spatiotemporal resolution is required. Therefore, in the present study, hourly AOD observations at 500 m resolution were retrieved from the geostationary ocean color imager (GOCI) using the simplified aerosol retrieval algorithm (SARA) over the urban area of Beijing for the year 2016. The SARA requires top-of-the-atmosphere (TOA) reflectance, solar and sensor geometry information and surface reflectance observations to retrieve an accurate AOD. For validation of the GOCI retrieved AOD, AOD measurements were obtained from the aerosol robotic network (AERONET) version 3 level 2.0 (cloud-screened and quality assured) data. The errors and uncertainties were reported using the root mean square error (RMSE), relative percent mean error (RPME), and the expected error (EE = ± (0.05 + 0.15AOD). Results showed that the high spatiotemporal GOCI AOD observations were well correlated with the AERONET AOD measurements with a correlation coefficient (R) of 0.92, RMSE of 0.07, and RPME of 5%, and 90% of the observations were within the EE. The results suggested that the SARA is robust and has the ability to retrieve high-resolution spatiotemporal AOD observations over the urban area using the geostationary satellite.

Keywords: AEORNET, AOD, SARA, GOCI, Beijing

Procedia PDF Downloads 153

Authors: H. R. Vosoughifar, Seyedeh Zeinab. Hosseininejad, Nahid Shabazi, Seyed Mohialdin Hosseininejad

Abstract:

In recent years, structure designers advocate further application of energy absorption devices for lateral loads damping. The Un-bonded Braced Frame (UBF) system is one of the efficient damping systems, which is made of a smart combination of steel and concrete or mortar. In this system, steel bears the earthquake-induced axial force as compressive or tension forces without loss of strength. Concrete or mortar around the steel core acts as a constraint for brace and prevents brace buckling during seismic axial load. In this study, the optimal bracing system in the high-rise structures has been evaluated considering the seismic stress distribution in the connections. An actual 18-story structure was modeled using the proper Finite Element (FE) software where braced with UBF, Eccentrically Braced Frames (EBF) and Concentrically Braced Frame (CBF) systems. Nonlinear static pushover and time-history analyses are then performed so that the acquired results demonstrate that the UBF system reduces drift values in the high-rise buildings. Further statistical analyses show that there is a significant difference between the drift values of UBF system compared with those resulted from the EBF and CBF systems. Hence, the seismic stress distribution in the connections of the proposed structure which braced with UBF system was investigated.

Keywords: optimal bracing system, high-rise structure, finite element analysis (FEA), seismic stress

Procedia PDF Downloads 417

Authors: Manuel Salado, Mikel Rincón, Arkaitz Fidalgo, Roberto Fernandez, Senentxu Lanceros-Méndez

Abstract:

Lithium-ion batteries (LIBs) are a promising technology for energy storage, but they suffer from safety concerns due to the use of flammable organic solvents in their liquid electrolytes. Solid-state electrolytes (SSEs) offer a potential solution to this problem, but they have their own limitations, such as poor ionic conductivity and high interfacial resistance. The aim of this research was to develop a new type of SSE based on metal-organic frameworks (MOFs) and ionic liquids (ILs). MOFs are porous materials with high surface area and tunable electronic properties, making them ideal for use in SSEs. ILs are liquid electrolytes that are non-flammable and have high ionic conductivity. A series of MOFs were synthesized, and their electrochemical properties were evaluated. The MOFs were then infiltrated with ILs to form a quasi-solid gel and solid xerogel SSEs. The ionic conductivity, interfacial resistance, and electrochemical performance of the SSEs were characterized. The results showed that the MOF-IL SSEs had significantly higher ionic conductivity and lower interfacial resistance than conventional SSEs. The SSEs also exhibited excellent electrochemical performance, with high discharge capacity and long cycle life. The development of MOF-IL SSEs represents a significant advance in the field of solid-state electrolytes. The high ionic conductivity and low interfacial resistance of the SSEs make them promising candidates for use in next-generation LIBs. The data for this research was collected using a variety of methods, including X-ray diffraction, scanning electron microscopy, and electrochemical impedance spectroscopy. The data was analyzed using a variety of statistical and computational methods, including principal component analysis, density functional theory, and molecular dynamics simulations. The main question addressed by this research was whether MOF-IL SSEs could be developed that have high ionic conductivity, low interfacial resistance, and excellent electrochemical performance. The results of this research demonstrate that MOF-IL SSEs are a promising new type of solid-state electrolyte for use in LIBs. The SSEs have high ionic conductivity, low interfacial resistance, and excellent electrochemical performance. These properties make them promising candidates for use in next-generation LIBs that are safer and have higher energy densities.

Keywords: energy storage, solid-electrolyte, ionic liquid, metal-organic-framework, electrochemistry, organic inorganic plastic crystal

Procedia PDF Downloads 66

Authors: Mikael M. Johansson, Peter Stenvall, Leif Karlsson, Joel Andersson

Abstract:

Sandvik Sanicro 25, UNS S31035, is an advanced high temperature austenitic stainless steel that potentially can be used in super-heaters and reheaters in the next generation of advanced ultra-super critical power plants. The material possesses both high creep strength and good corrosion resistance at temperatures up to 700°C. Its high temperature properties are positioned between other commercially available high temperature austenitic stainless steels and nickel-based alloys. It is, however, well known that an austenitic solidification mode combined with a fully austenitic microstructure exacerbate susceptibility towards hot cracking. The problem increases even more for thick walled material in multipass welding and could compromise the integrity of the welded component. Varestraint weldability testing is commonly used to evaluate susceptibility towards hot cracking of materials. In this paper, Varestraint test results are evaluated for base material of both UNS S31035 steel and are compared to those of the well-known and well-characterized UNS S31008 grade. The more creep resistant alloy, UNS S31035, is metallurgically more complicated than the UNS S31008 grade and has additions of several alloying elements to improve its high temperature properties. It benefits from both solid solution hardening as well as precipitation hardening. This investigation therefore attempts, based on the Varestraint weldability test, to understand if there are any differences in cracking mechanisms between these two grades due to the additional alloying elements used in UNS S31035. Results from Varestraint testing and crack type investigations will be presented and discussed in some detail. It is shown that hot cracking susceptibility of the UNS S31035 steel is only slightly higher than that of UNS S31008 despite the more complicated metallurgy. Weldability of the two alloys is therefore judged to be comparable making the newer alloy well suited also for critical applications.

Keywords: austenitic stainless steel, hot cracking susceptibility, UNS S31035, UNS S31008, varestraint weldability testing

Procedia PDF Downloads 117

Authors: Wandera Stephen Ojumbo

Abstract:

People living with hearing impairment in Uganda are one of the most excluded minority groups in the country. The Uganda National Association of the Deaf estimates that deaf people make up 3.4% of Uganda’s 43 million people. Deaf Children and youth often appear withdrawn because they face social stigma. In 2009, photojournalist Stephen Wandera Ojumbo conducted an exhibition in Kampala titled “Silent Voices with colourful Hearts” showcasing the life of deaf children at Uganda School for the Deaf, Ntinda, in order to create awareness of their plight, raising funds for the construction of a vocational centre for the deaf that didn’t continue their education due to: lack of funds, non-inclusive educational institutions, and for those who cannot read and write. These children, whose lives were exhibited in 2009, are currently youths. In Uganda, there are just five primary schools for the deaf (three of these are located in Kampala, the capital city), and barely five secondary schools for the deaf. At the moment, some deaf children only receive special needs training equivalent to primary seven levels and the majority don’t make it to secondary school education level due to the fact that English is a second language to them. There is a communication gap between speaking parents and deaf children, which leads to the breakage of family bonds. The deaf youth run away from their homes to form a community where they can communicate freely. Likewise, employment opportunities for the deaf are equally very limited. It’s for this reason that a follow-up photo exhibition was conducted to expose more about what the youthful deaf people and their guardians go through in Uganda to get jobs, live and fit in the community, how they communicate and get understood, bonding with families instead of running away to bond with fellow deaf persons. The photo exhibition under the theme “Loud Silence” was significant in showcasing the ability of deaf youths in Uganda and eliciting solutions to make a more inclusive society for the deaf. It is hoped that partners in development will join in for intervention. The methodology used included individual interviews with the deaf youth and their parents and caretakers; photography at household and community levels; document review at organizations working with the deaf; observations; and key informant interviews with relevant personnel working with the deaf. Some of the major findings include: i) Effective sign language communication is key in deaf education, family bonding, and developing a sense of belonging; ii) Love and intimacy can keep the deaf bound together; iii) Education is important; everybody should struggle even if alone; iv) Games and sports are a unifying factor and most loved among the deaf; and v) better communication skills build confidence in deaf youth. In conclusion, concerted efforts are still needed to make Uganda schools more inclusive for deaf persons. This will enable a secure future for deaf youths.

Keywords: deaf, education, excluded, photo exhibition

Procedia PDF Downloads 67

Authors: Hao Chen, Bo Guo, Ping Jiang

Abstract:

Residual life (RL) estimation based on multi-phase nonlinear Wiener process was studied in this paper, which is significant for complicated products with small samples. Firstly, nonlinear Wiener model with random parameter was introduced and multi-phase nonlinear Wiener model was proposed to model degradation process of products that were nonlinear and separated into different phases. Then the multi-phase RL probability density function based on the presented model was derived approximately in a closed form and parameters estimation was achieved with the method of maximum likelihood estimation (MLE). Finally, the method was applied to estimate the RL of high voltage plus capacitor. Compared with the other three different models by log-likelihood function (Log-LF) and Akaike information criterion (AIC), the results show that the proposed degradation model can capture degradation process of high voltage plus capacitors in a better way and provide a more reliable result.

Keywords: multi-phase nonlinear wiener process, residual life estimation, maximum likelihood estimation, high voltage plus capacitor

Procedia PDF Downloads 443

Authors: Esmaeil Zabihi, Seyed Hossein Alavi

Abstract:

The purpose of this study is a comparison of movement and physical fitness in athlete's male students in altitude and sea-level. The samples consist of 450 subjects in altitude and sea-level in Iran in years of 2013 which were selected randomly from the population. We investigated the effect of high altitude on the tests activity profile of youth high altitude and sea level residents. Methods 450 Sea Level (Mahmood Abad) and 450 Altitude-resident (Shahre-Kord) athlete students tests of physical fitness near sea level (-5 m) and in Altitude (2100 m). This study is Descriptive Research (causal-comparative research). The tests of physical fitness include pull-ups test, sit-ups test, agility test(4 9), 45 sprint test, 1600 m running, long jump, and flexibility test. For determining of different between the physical fitness of altitude and sea-level students was used t-test (P ≤ 0.05). The result of this study show that there is no significant difference between the average of pull-ups test, flexibility, 45 sprints, and agility (4 9) test of students in sea-level and altitude. But there is a significant difference between the average of sit-ups, 1600 m running and long jump in altitude. The students of altitude have higher power rather than sea-level. But the students of sea-level have stronger abdominal muscles and cardio-respiratory endurance rather than altitude. High altitude reduces the distance covered by youth athlete students during tests. Neither acclimatisation nor lifelong residence at high altitude protects against detrimental effects of altitude on tests activity profile.

Keywords: physical fitness, sea level, altitude areas, AAHPERD test

Procedia PDF Downloads 422

Authors: Arvind Mittal, Rajesh Gupta

Abstract:

Influence of heat input on the micro structure and mechanical properties of shield metal arc welded of duplex stainless steel UNSNO.S-31803 has been investigated. Three heat input combinations designated as low heat (0.675 KJ/mm), medium heat (0.860 KJ/mm) and high heat (1.094 KJ/mm) and weld joints made using these combinations were subjected to micro structural evaluations and tensile and impact testing so as to analyze the effect of thermal arc energy on the micro structure and mechanical properties of these joints. The result of this investigation shows that the joints made using low heat input exhibited higher tensile strength than those welded with medium and high heat input. Heat affected zone of welded joint made with medium heat input has austenitic ferritic grain structure with some patchy austenite provide high toughness. Significant grain coarsening was observed in the heat affected zone (HAZ) of medium and high heat input welded joints, whereas low heat input welded joint shows the fine grain structure in the heat affected zone with small amount of dendritic formation and equiaxed grain structure where inner zone indicates slowly cooled grains in the direction of heat dissipation. This is the main reason for the observable changes of tensile properties of weld joints welded with different arc energy inputs.

Keywords: microstructure, mechanical properties, shield metal arc welded, duplex stainless steel

Procedia PDF Downloads 269

Authors: Christian Andrä, Luisa Zimmermann, Christina Müller

Abstract:

Introduction: The positive relation between physical activity and cognition is commonly known. Relevant studies show that in everyday school life active breaks can lead to improvement in certain abilities (e.g. attention and concentration). A beneficial effect is in particular attributed to moderate activity. It is still unclear whether active breaks are beneficial after relatively short phases of cognitive load and whether the postulated effects of activity really have an immediate impact. The objective of this study was to verify whether an active break after 18 minutes of cognitive load leads to enhanced attention/concentration performance, compared to inactive breaks with voluntary mobile phone activity. Methodology: For this quasi-experimental study, 36 students [age: 14.0 (mean value) ± 0.3 (standard deviation); male/female: 21/15] of a secondary school were tested. In week 1, every student’s maximum heart rate (Hfmax) was determined through maximum effort tests conducted during physical education classes. The task was to run 3 laps of 300 m with increasing subjective effort (lap 1: 60%, lap 2: 80%, lap 3: 100% of the maximum performance capacity). Furthermore, first attention/concentration tests (D2-R) took place (pretest). The groups were matched on the basis of the pretest results. During week 2 and 3, crossover testing was conducted, comprising of 18 minutes of cognitive preload (test for concentration performance, KLT-R), a break and an attention/concentration test after a 2-minutes transition. Different 10-minutes breaks (active break: moderate physical activity with 65% Hfmax or inactive break: mobile phone activity) took place between preloading and transition. Major findings: In general, there was no impact of the different break interventions on the concentration test results (symbols processed after physical activity: 185.2 ± 31.3 / after inactive break: 184.4 ± 31.6; errors after physical activity: 5.7 ± 6.3 / after inactive break: 7.0. ± 7.2). There was, however, a noticeable development of the values over the testing periods. Although no difference in the number of processed symbols was detected (active/inactive break: period 1: 49.3 ± 8.8/46.9 ± 9.0; period 2: 47.0 ± 7.7/47.3 ± 8.4; period 3: 45.1 ± 8.3/45.6 ± 8.0; period 4: 43.8 ± 7.8/44.6 ± 8.0), error rates decreased successively after physical activity and increased gradually after an inactive break (active/inactive break: period 1: 1.9 ± 2.4/1.2 ± 1.4; period 2: 1.7 ± 1.8/ 1.5 ± 2.0, period 3: 1.2 ± 1.6/1.8 ± 2.1; period 4: 0.9 ± 1.5/2.5 ± 2.6; p= .012). Conclusion: Taking into consideration only the study’s overall results, the hypothesis must be dismissed. However, more differentiated evaluation shows that the error rates decreased after active breaks and increased after inactive breaks. Obviously, the effects of active intervention occur with a delay. The 2-minutes transition (regeneration time) used for this study seems to be insufficient due to the longer adaptation time of the cardio-vascular system in untrained individuals, which might initially affect the concentration capacity. To use the positive effects of physical activity for teaching and learning processes, physiological characteristics must also be considered. Only this will ensure optimum ability to perform.

Keywords: active breaks, attention/concentration test, cognitive performance capacity, heart rate, physical activity

Procedia PDF Downloads 301

Authors: Lumindu Dilumka, Ranaweera I. D., Sudusinghe S. P., Sanduni Kanchana A. M. K.

Abstract:

This study was motivated by the challenges experienced by parents and guardians in ensuring the safety of children in cyberspace. In the last two or three years, online education has become very popular all over the world due to the Covid 19 pandemic. Therefore, parents, guardians and teachers must ensure the safety of children in cyberspace. Children are more likely to go astray and there are plenty of online programs are waiting to get them on the wrong track and also, children who are engaging in the online education can be distracted at any moment. Therefore, parents should keep a close check on their children's online activity. Apart from that, due to the unawareness of children, they tempt to share their sensitive information, causing a chance of being a victim of phishing attacks from outsiders. These problems can be overcome through the proposed web-based system. We use feature extraction, web tracking and analysis mechanisms, image processing and name entity recognition to implement this web-based system.

Keywords: online education, cyber bullying, social media, face recognition, web tracker, privacy data

Procedia PDF Downloads 70

Authors: Jayati Bhattacharjee

Abstract:

Teaching is a very dynamic profession. Teaching Science is as much challenging as Learning the subject if not more. For instance teaching of Chemistry. From the introductory concepts of subatomic particles to atoms of elements and their symbols and further presenting the chemical equation and so forth is a challenge on both side of the equation Teaching Learning. This paper combines the Neuroscience of Learning and memory with the knowledge of Learning style (VAK) and presents an effective tool for the teacher to authenticate Learning. The model of ‘Working Memory’, the Visio-spatial sketchpad, the central executive and the phonological loop that transforms short-term memory to long term memory actually supports the psychological theory of Learning style i.e. Visual –Auditory-Kinesthetic. A closer examination of David Kolbe’s learning model suggests that learning requires abilities that are polar opposites, and that the learner must continually choose which set of learning abilities he or she will use in a specific learning situation. In grasping experience some of us perceive new information through experiencing the concrete, tangible, felt qualities of the world, relying on our senses and immersing ourselves in concrete reality. Others tend to perceive, grasp, or take hold of new information through symbolic representation or abstract conceptualization – thinking about, analyzing, or systematically planning, rather than using sensation as a guide. Similarly, in transforming or processing experience some of us tend to carefully watch others who are involved in the experience and reflect on what happens, while others choose to jump right in and start doing things. The watchers favor reflective observation, while the doers favor active experimentation. Any lesson plan based on the model of Prescriptive design: C+O=M (C: Instructional condition; O: Instructional Outcome; M: Instructional method). The desired outcome and conditions are independent variables whereas the instructional method is dependent hence can be planned and suited to maximize the learning outcome. The assessment for learning rather than of learning can encourage, build confidence and hope amongst the learners and go a long way to replace the anxiety and hopelessness that a student experiences while learning Science with a human touch in it. Application of this model has been tried in teaching chemistry to high school students as well as in workshops with teachers. The response received has proven the desirable results.

Keywords: working memory model, learning style, prescriptive design, assessment for learning

Procedia PDF Downloads 334

Authors: G. S. Sumanasekara, W. M. P. B. Weerasingheg

Abstract:

The major problem associated with concentrate feeds used for feeding cattle is declining quality by contamination with Aflatoxins. Objective: The aim of the study was to detect levels of Aflatoxin M1(AFM1) in cow milk , AFM1 levels present in milk related to different feed types and to identify the relationship between feed type and Aflatoxin M1 in milk. Design: cross sectional study design. Milk samples from each farm assessed for presence of AFM1 using High Performance Liquid Chromatographic method. Setting: Ten dairy farms located in Nuwara-Eliya district were randomly selected.AFM1 analysis was done using High Performance Liquid Chromatography(HPLC). Results: The results indicated that AFM1 was present in 50% of samples. Coconut poonac shown the most significant relationship among individual feeds having a correlation of 0.65 and P value of 0.042 . Among feed combinations, coconut poonac and beer pulp combination showed the highest correlation of 0.77 and P value of 0.05. Grasses had shown a very poor relationship with the AFM1 occurrence in milk (r=0.053, P=0.885). Relationship between overall concentrate feeds in the study and AFM1 in milk, it was clear that they had a significant relationship having correlation of 0.65 and P value of 0.042. Majority of samples lied between 0-10 ng L-1 of AFM1 and one sample exceeded above 30 ng L-1. Two samples had AFM1 concentrations between 22-32 ng L-1. One sample lied between 32-42ng L-1, did not exceed the EU recommended level of 50 ng L-1. The presence of AFM1 in milk under various management and feeding conditions is yet to be investigated in Sri Lanka.

Keywords: aflatoxin M1, aspergillus, cattle feed, concentrates, cow milk, high perforamance liquid chromatography

Procedia PDF Downloads 281

Authors: Rafika Bibi, Khaled Khaladi, Hind Mokran, Mohamed Salah Boukhechem

Abstract:

A high performance liquid chromatographic method with ultraviolet detection at 264nm was developed and validate for quantitative determination and separation of cefazolin and cefotaxime in urine, the mobile phase consisted of acetonitrile and phosphate buffer pH4,2(15 :85) (v/v) pumped through ODB 250× 4,6 mm, 5um column at a flow rate of 1ml/min, loop of 20ul. In this condition, the validation of this technique showed that it is linear in a range of 0,01 to 10ug/ml with a good correlation coefficient ( R>0,9997), retention time of cefotaxime, cefazolin was 9.0, 10.1 respectively, the statistical evaluation of the method was examined by means of within day (n=6) and day to day (n=5) and was found to be satisfactory with high accuracy and precision.

Keywords: cefazolin, cefotaxime, HPLC, bioscience, biochemistry, pharmaceutical

Procedia PDF Downloads 346

Authors: Sreevalli Bokka

Abstract:

Various technologies are emerging to capture or reduce carbon intensity from a gas stream, such as industrial effluent air and atmosphere. Of these technologies, filter membranes are emerging as a key player in carbon sequestering. The key advantages of these membranes are their high surface area and porosity. Fabricating a filter membrane that has high selectivity for carbon sequestration is challenging as material properties and processing parameters affect the membrane properties. In this study, the growth of the filter membranes and the critical material properties that impact carbon sequestration are presented.

Keywords: membranes, filtration, separations, polymers, carbon capture

Procedia PDF Downloads 56

Authors: Yoonsuh Jung

Abstract:

As DNA microarray data contain relatively small sample size compared to the number of genes, high dimensional models are often employed. In high dimensional models, the selection of tuning parameter (or, penalty parameter) is often one of the crucial parts of the modeling. Cross-validation is one of the most common methods for the tuning parameter selection, which selects a parameter value with the smallest cross-validated score. However, selecting a single value as an "optimal" value for the parameter can be very unstable due to the sampling variation since the sample sizes of microarray data are often small. Our approach is to choose multiple candidates of tuning parameter first, then average the candidates with different weights depending on their performance. The additional step of estimating the weights and averaging the candidates rarely increase the computational cost, while it can considerably improve the traditional cross-validation. We show that the selected value from the suggested methods often lead to stable parameter selection as well as improved detection of significant genetic variables compared to the tradition cross-validation via real data and simulated data sets.

Keywords: cross validation, parameter averaging, parameter selection, regularization parameter search

Procedia PDF Downloads 405

Authors: Yuliya Markava

Abstract:

The laser in situ keratomileusis (LASIK) is widely common surgical procedure, which has become an alternative for patients who are not satisfied with the performance of other correction methods. A high level of patient satisfaction functional outcomes after refractive surgery confirms the high reliability and safety of LASIK and provides a significant improvement in the quality of life and social adaptation. Purpose: To perform clinical analysis of the results of correction made to the excimer laser system SCHWIND AMARIS 500E in patients with different types of refractive anomalies. Materials and Methods: This was a retrospective analysis of 1581 operations (812 patients): 413 males (50.86%) and 399 females (49.14%) at the age from 18 to 47 years with different types of ametropia. All operations were performed on excimer laser SCHWIND AMARIS 500E in the LASIK procedure. Formation of the corneal flap was made by mechanical microkeratome SCHWIND. Results: Analyzing the structure of refractive anomalies: The largest number of interventions accounted for myopia: 1505 eyes (95.2%), of which about a low myopia: 706 eyes (44.7%), moderate myopia: 562 eyes (35.5 %), high myopia: eyes 217 (13.7%) and supermyopia: 20 eyes (1.3%). Hyperopia was 0.7% (11 eyes), mixed astigmatism: 4.1% (65 eyes). The efficiency was 80% (in patients with supermyopia) to 91.6% and 95.4% (in groups with myopia low and moderate, respectively). Uncorrected visual acuity average values before and after laser operation was in groups: a low myopia 0.18 (up 0.05 to 0.31) and 0.80 (up 0.60 to 1.0); moderate myopia 0.08 (up 0.03 to 0.13) and 0.87 ( up 0.74 to 1.0); high myopia 0.05 (up 0.02 to 0.08) and 0.83 (up 0.66 to 1.0); supermyopia 0.03 (up 0.02 to 0.04) and 0.59 ( up 0.34 to 0.84); hyperopia 0.27 (up 0.16 to 0.38) and 0.57 (up 0.27 to 0.87); mixed astigmatism of 0.35 (up 0.19 to 0.51) and 0.69 (up 0.44 to 0.94). In all cases, after LASIK indicators uncorrected visual acuity significantly increased. Reoperation was 4.43%. Significance: Clinical results of refractive surgery at the excimer laser system SCHWIND AMARIS 500E in different ametropia correction is characterized by high efficiency.

Keywords: effectiveness of laser correction, LASIK, refractive anomalies, surgical treatment

Procedia PDF Downloads 241

Authors: Prince Vivek, Vijay Kumar Bharti, Deepak Kumar, Rohit Kumar, Kapil Nehra, Dhananjay Singh, Om Prakash Chaurasia, Bhuvnesh Kumar

Abstract:

High altitude native people still rely heavily on animal transport for logistic support at eastern and northern Himalayas regions. The prevalent mountainous terrains and rugged region are not suitable for the motorized vehicle to use in logistic transport. Therefore, people required high endurance pack animals for load carrying and riding. So far to the best of our knowledge, no studies have been taken to evaluate the effect of loads on the physiology of ponies in high altitude region. So, in this view, we evaluated variation in physiological, hematological, biochemical, and cytokines indices of Zanskar ponies during load carrying at high altitude. Total twelve (12) of Zanskar ponies, mare, age 4-6 years selected for this study, Feed was offered at 2% of body weight, and water ad libitum. Ponies were divided into three groups; group-A (without load), group-B (60 kg), and group-C (80 kg) of backpack loads. The track was very narrow and slippery with gravel, uneven with a rocky surface and has a steep gradient of 4 km uphill at altitude 3291 to 3500m. When we evaluate these parameters, it is understood that the heart rate, pulse rate, and respiration rate was significantly increased in 80 kg group among the three groups. The hematology parameters viz. hemoglobin significantly increased in 80 kg group on 1st day after load carrying among the three groups which was followed by control and 60 kg whereas, PCV, lymphocytes, monocytes percentage significantly increased however, ESR and eosinophil % significantly decreased in 80 kg group after load carrying on 7th day after load carrying among the three groups which were followed by control and 60 kg group. In biochemical parameters viz. LA, LDH, TP, hexokinase (HK), cortisol (CORT), T3, GPx, FRAP and IL-6 significantly increased in 80 kg group on the 7th day after load carrying among the three groups which were followed by control and 60 kg group. The ALT, ALB, GLB, UR, and UA significantly increased in 80 kg group on the 7th day before and after load carrying among the three groups which were followed by control and 60 kg group. The CRT, AST, and CK-MB were significantly increased in 80 kg group on the 1st and 7th day after load carrying among the three groups which were followed by control and 60 kg group. It has been concluded that, heart rate, respiration rate, hematological indices like PCV, lymphocytes, monocytes, Hb and ESR, biochemical indices like lactic acid, LDH, TP, HK, CORT, T3, ALT, AST and CRT, ALB, GLB, UR, UA, GPx, FRAP and IL-6 are important biomarkers to assess effect of load on animal physiology and endurance. Further, this result has revealed the strong correlation of change in biomarkers level with performance in ponies during load carry. Hence, these parameters might be used for the performance of endurance of Zanskar ponies in the high mountain region.

Keywords: biochemical, endurance, high altitude, load, ponies

Procedia PDF Downloads 265

Authors: Nadezhda Nikolaeva, Tatyana Alexandrova, Alexandr Alexandrov

Abstract:

Processing of high-silicon bauxite on the base of the traditional clinkering method is related to high power consumption and capital investments, which makes production of alumina from those ores non-competitive in terms of basic economic showings. For these reasons, development of technological solutions enabling to process bauxites with various chemical and mineralogical structures efficiently with low level of thermal power consumption is important. Flow sheet of the studies on washability of ores from the Timanskoe and the Severo-Onezhskoe deposits is on the base of the flotation method.

Keywords: low-quality bauxite, resource-saving technology, optimization, aluminum, conditioning of composition, separation characteristics

Procedia PDF Downloads 271

Authors: Rafael Santos, Clara Pimenta Do Vale, Barbara Bogoni, Poul Henning Kirkegaard

Abstract:

In the last decades, the relevance of hand drawing has decreased in the scope of architectural education. However, some schools continue to recognize its decisive role, not only in the architectural design teaching, but in the whole of architectural training. With this paper it is intended to present the results of a research developed on the following problem: the practise of hand drawing as a premier form of representation in architectural design teaching. The research had as its object the educational model of the Faculty of Architecture of the University of Porto (FAUP) and was led by three main objectives: to identify the circumstance that promoted hand drawing as a form of representation in FAUP's model; to characterize the types of hand drawing and their role in that model; to determine the particularities of hand drawing as a premier form of representation in architectural design teaching. Methodologically, the research was conducted according to a qualitative embedded single-case study design. The object – i.e., the educational model – was approached in FAUP case considering its Context and three embedded unities of analysis: the educational Purposes, Principles and Practices. In order to guide the procedures of data collection and analysis, a Matrix for the Characterization (MCC) was developed. As a methodological tool, the MCC allowed to relate the three embedded unities of analysis with the three main sources of evidence where the object manifests itself: the professors, expressing how the model is Assumed; the architectural design classes, expressing how the model is Achieved; and the students, expressing how the model is Acquired. The main research methods used were the naturalistic and participatory observation, in-person-interview and documentary and bibliographic review. The results reveal that the educational model of FAUP – following the model of the former Porto School – was largely due to the methodological foundations created with the hand drawing teaching-learning processes. In the absence of a culture of explicit theoretical elaboration or systematic research, hand drawing was the support for the continuity of the school, an expression of a unified thought about what should be the reflection and practice of architecture. As a form of representation, hand drawing plays a transversal role in the entire educational model, since its purposes are not limited to the conception of architectural design – it is also a means for perception, analysis and synthesis. Regarding the architectural design teaching, there seems to be an understanding of three complementary dimensions of didactics: the instrumental, methodological and propositional dimension. At FAUP, hand drawing is recognized as the common denominator among these dimensions, according to the idea of "globality of drawing". It is expected that the knowledge base developed in this research may have three main contributions: to contribute to the maintenance and valorisation of FAUP’s model; through the precise description of the methodological procedures, to contribute by transferability to similar studies; through the critical and objective framework of the problem underlying the hand drawing in architectural design teaching, to contribute to the broader discussion concerning the contemporary challenges on architectural education.

Keywords: architectural design teaching, architectural education, forms of representation, hand drawing

Procedia PDF Downloads 115

Authors: Nader Pourmahmoud, Amir Hassanzadeh

Abstract:

This article investigates the effects of inlet pressure in a newly introduced vortex tube which has been equipped with an additional vortex chamber. A 3-D compressible turbulent flow computation has been carried out toward analysis of complex flow field in this apparatus. Numerical results of flows are derived by utilizing the standard k-ε turbulence model for analyzing high rotating complex flow field. The present research has focused on cooling effect and given a characteristics curve for minimum cool temperature. In addition, the effect of inlet pressure for both chambers has been studied in details. To be presented numerical results show that the effect of inlet pressure in second chamber has more important role in improving the performance of the vortex tube than first one. By increasing the pressure in the second chamber, cold outlet temperature reaches a higher decrease. When both chambers are fed with high pressure fluid, best operation condition of vortex tube occurs. However, it is not possible to feed both chambers with high pressure due to the conditions of working environment.

Keywords: energy separation, inlet pressure, numerical simulation, vortex chamber, vortex tube

Procedia PDF Downloads 357

Authors: Michalina Aniola, Andrzej Katrusiak

Abstract:

4,4-Bipyridine is an important compound often used in chemical practice and more recently frequently applied for designing new metal organic framework (MoFs). Here we present a systematic high-pressure study of its hydrobromide salt. 4,4-Bipyridine hydrobromide monohydrate, 44biPyHBrH₂O, at ambient-pressure is orthorhombic, space group P212121 (phase a). Its hydrostatic compression shows that it is stable to 1.32 GPa at least. However, the recrystallization above 0.55 GPa reveals a new hidden b-phase (monoclinic, P21/c). Moreover, when the 44biPyHBrH2O is heated to high temperature the chemical reactions of this compound in methanol solution can be observed. High-pressure experiments were performed using a Merrill-Bassett diamond-anvil cell (DAC), modified by mounting the anvils directly on the steel supports, and X-ray diffraction measurements were carried out on a KUMA and Excalibur diffractometer equipped with an EOS CCD detector. At elevated pressure, the crystal of 44biPyHBrH₂O exhibits several striking and unexpected features. No signs of instability of phase a were detected to 1.32 GPa, while phase b becomes stable at above 0.55 GPa, as evidenced by its recrystallizations. Phases a and b of 44biPyHBrH2O are partly isostructural: their unit-cell dimensions and the arrangement of ions and water molecules are similar. In phase b the HOH-Br- chains double the frequency of their zigzag motifs, compared to phase a, and the 44biPyH+ cations change their conformation. Like in all monosalts of 44biPy determined so far, in phase a the pyridine rings are twisted by about 30 degrees about bond C4-C4 and in phase b they assume energy-unfavorable planar conformation. Another unusual feature of 44biPyHBrH2O is that all unit-cell parameters become longer on the transition from phase a to phase b. Thus the volume drop on the transition to high-pressure phase b totally depends on the shear strain of the lattice. Higher temperature triggers chemical reactions of 44biPyHBrH2O with methanol. When the saturated methanol solution compound precipitated at 0.1 GPa and temperature of 423 K was required to dissolve all the sample, the subsequent slow recrystallization at isochoric conditions resulted in disalt 4,4-bipyridinium dibromide. For the 44biPyHBrH2O sample sealed in the DAC at 0.35 GPa, then dissolved at isochoric conditions at 473 K and recrystallized by slow controlled cooling, a reaction of N,N-dimethylation took place. It is characteristic that in both high-pressure reactions of 44biPyHBrH₂O the unsolvated disalt products were formed and that free base 44biPy and H₂O remained in the solution. The observed reactions indicate that high pressure destabilized ambient-pressure salts and favors new products. Further studies on pressure-induced reactions are carried out in order to better understand the structural preferences induced by pressure.

Keywords: conformation, high-pressure, negative area compressibility, polymorphism

Procedia PDF Downloads 234