Search results for: Liquid acquisition device
552 Development of Single Layer of WO3 on Large Spatial Resolution by Atomic Layer Deposition Technique
Authors: S. Zhuiykov, Zh. Hai, H. Xu, C. Xue
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Unique and distinctive properties could be obtained on such two-dimensional (2D) semiconductor as tungsten trioxide (WO3) when the reduction from multi-layer to one fundamental layer thickness takes place. This transition without damaging single-layer on a large spatial resolution remained elusive until the atomic layer deposition (ALD) technique was utilized. Here we report the ALD-enabled atomic-layer-precision development of a single layer WO3 with thickness of 0.77±0.07 nm on a large spatial resolution by using (tBuN)2W(NMe2)2 as tungsten precursor and H2O as oxygen precursor, without affecting the underlying SiO2/Si substrate. Versatility of ALD is in tuning recipe in order to achieve the complete WO3 with desired number of WO3 layers including monolayer. Governed by self-limiting surface reactions, the ALD-enabled approach is versatile, scalable and applicable for a broader range of 2D semiconductors and various device applications.Keywords: Atomic layer deposition, tungsten oxide, WO3, two-dimensional semiconductors, single fundamental layer.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1636551 Computational Fluid Dynamics Study on Water Soot Blower Direction in Tangentially Fired Pulverized-Coal Boiler
Authors: Teewin Plangsrinont, Wasawat Nakkiew
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In this study, Computational Fluid Dynamics (CFD) was utilized to simulate and predict the path of water from water soot blower through an ambient flow field in 300-megawatt tangentially burned pulverized coal boiler that utilizes a water soot blower as a cleaning device. To predict the position of the impact of water on the opposite side of the water soot blower under identical conditions, the nozzle size and water flow rate were fixed in this investigation. The simulation findings demonstrated a high degree of accuracy in predicting the direction of water flow to the boiler's water wall tube, which was validated by comparison to experimental data. Results show maximum deviation value of the water jet trajectory is 10.2%.
Keywords: Computational fluid dynamics, tangentially fired boiler, thermal power plant, water soot blower.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 718550 Subthreshold Circuit Performance Investigation under Temperature Variations
Authors: Mohd. Hasan, Ajmal Kafeel, S. D. Pable
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Ultra-low-power (ULP) circuits have received widespread attention due to the rapid growth of biomedical applications and Battery-less Electronics. Subthreshold region of transistor operation is used in ULP circuits. Major research challenge in the subthreshold operating region is to extract the ULP benefits with minimal degradation in speed and robustness. Process, Voltage and Temperature (PVT) variations significantly affect the performance of subthreshold circuits. Designed performance parameters of ULP circuits may vary largely due to temperature variations. Hence, this paper investigates the effect of temperature variation on device and circuit performance parameters at different biasing voltages in the subthreshold region. Simulation results clearly demonstrate that in deep subthreshold and near threshold voltage regions, performance parameters are significantly affected whereas in moderate subthreshold region, subthreshold circuits are more immune to temperature variations. This establishes that moderate subthreshold region is ideal for temperature immune circuits.Keywords: Subthreshold, temperature variations, ultralow power.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2313549 Effect of COD Loading Rate on Hydrogen Production from Alcohol Wastewater
Authors: Patcharee Intanoo, Jittipan Chavadej, Sumaeth Chavadej
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The objective of this study was to investigate hydrogen production from alcohol wastewater by anaerobic sequencing batch reactor (ASBR) under thermophillic operation. The ASBR unit used in this study had a liquid holding volume of 4 L and was operated at 6 cycles per day. The seed sludge taken from an upflow anaerobic sludge blanket unit treating the same wastewater was boiled at 95 °C for 15 min before being fed to the ASBR unit. The ASBR system was operated at different COD loading rates at a thermophillic temperature (55 °C), and controlled pH of 5.5. When the system was operated under optimum conditions (providing maximum hydrogen production performance) at a feed COD of 60 000 mg/l, and a COD loading rate of 68 kg/m3 d, the produced gas contained 43 % H2 content in the produced gas. Moreover, the hydrogen yield and the specific hydrogen production rate (SHPR) were 130 ml H2/g COD removed and 2100 ml H2/l d, respectively.
Keywords: Biohydrogen, Alcohol wastewater, Anaerobic sequencing batch reactor (ASBR), Thermophillic operation
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2108548 Implementation of a Virtual Testbed for Secure IoT Firmware Update Using Blockchain
Authors: Tarun Chand, Michael Jurczyk
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With the increasing need and popularity of IoT devices and how integrated they are becoming in our daily lives and industries; these devices make for a very lucrative target for malicious actors. And since these devices have such limited resources, the implementation of robust security features is a tradeoff to be made for the actual functionality the device was intended for. This makes them an easy target with high returns. Several frameworks for the secure firmware update of these devices have been recently proposed in the literature. They focus on methods such as blockchains and distributed file systems to secure firmware updates, but do not go into the details of the actual implementation of these frameworks and the lower-level interactions among these methods used. This work integrates some of these security measures into one overall framework and details the actual lower-level implementation of this framework in a virtual dockerized testbed running on AWS.
Keywords: Blockchain, Ethereum, Geth, IPFS, secure IoT-firmware update, virtual testbed development
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 86547 Ultrasound Assisted Method to Increase the Aluminum Dissolve Rate from Acidified Water
Authors: Wen Po Cheng, Chi Hua Fu, Ping Hung Chen, Ruey Fang Yu
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Aluminum salt that is generally presents as a solid phase in the water purification sludge (WPS) can be dissolved, recovering a liquid phase, by adding strong acid to the sludge solution. According to the reaction kinetics, when reactant is in the form of small particles with a large specific surface area, or when the reaction temperature is high, the quantity of dissolved aluminum salt or reaction rate, respectively are high. Therefore, in this investigation, water purification sludge (WPS) solution was treated with ultrasonic waves to break down the sludge, and different acids (1 N HCl and 1 N H2SO4) were used to acidify it. Acid dosages that yielded the solution pH of less than two were used. The results thus obtained indicate that the quantity of dissolved aluminum in H2SO4-acidified solution exceeded that in HCl-acidified solution. Additionally, ultrasonic treatment increased the rate of dissolution of aluminum and the amount dissolved. The quantity of aluminum dissolved at 60℃ was 1.5 to 2.0 times higher than that at 25℃.Keywords: Coagulant, Aluminum, Ultrasonic, Acidification, Temperature, Sludge.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2284546 Life Cycle Assessment of Expressway Passenger Transport Service: A Case Study of Thailand
Authors: Watchara Surawong, Cheema Soralumn
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This research work is concerned with the life cycle assessment (LCA) of an expressway, as well as its infrastructure, in Thailand. The life cycle of an expressway encompasses the raw material acquisition phase, the construction phase, the use or service phase, the rehabilitation phase, and finally the demolition and disposal phase. The LCA in this research was carried out using CML baseline 2000 and in accordance with the ISO 14040 standard. A functional unit refers to transportation of one person over one kilometer of a 3-lane expressway with a 50-year lifetime. This research has revealed that the construction phase produced the largest proportion of the environmental impact (81.46%), followed by the service, rehabilitation, demolition and disposal phases and transportation at 11.97%, 3.72% 0.33% and 2.52%, respectively. For the expressway under study, the total carbon footprint over its lifetime is equivalent to 245,639 tons CO2-eq per 1 kilometer functional unit, with the phases of construction, service, rehabilitation, demolition and disposal and transportation contributing 153,690; 73,773; 3693, 755 and 13,728 tons CO2-eq, respectively. The findings could be adopted as a benchmark against which the environmental impacts of future similar projects can be measured.
Keywords: Environmental impact assessment, Life cycle assessment, LCA, Expressway passenger transport service, Carbon footprint, Eco-friendly expressway.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2319545 Effect of Butachlor on the Microbial Population of Direct Sown Rice
Authors: Kalyanasundaram.D., Kavitha. S
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Field experiments were conducted at Annamalai University Experimental Farm, Department of Agronomy; to device suitable weed control measures for direct seeded puddled rice and to study the effect of the weed control measures on the soil microbial population. The treatments comprised of incorporation of pressmud @ 6.25 t ha-1 and application of herbicide butachlor @1.5 kg a. i. ha- 1 with and without safener 4 days after sowing (DAS), 8 DAS alone and also in conjunction with hand weeding at 30 DAS. Hand weeding twice and a weedy check were also maintained. At maximum tillering stage, the population of bacteria was significantly reduced by butachlor application. The injury to microbes caused by herbicide disappeared with the advancement of crop's age and at flowering stage of crop, there was no significant difference among the treatments. The fungal and actinomycetes population remained unaltered by weed control treatments at both the stages of observation.
Keywords: Butachlor, Herbicide, Direct sown rice, Microbial population
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1800544 Inversion of Electrical Resistivity Data: A Review
Authors: Shrey Sharma, Gunjan Kumar Verma
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High density electrical prospecting has been widely used in groundwater investigation, civil engineering and environmental survey. For efficient inversion, the forward modeling routine, sensitivity calculation, and inversion algorithm must be efficient. This paper attempts to provide a brief summary of the past and ongoing developments of the method. It includes reviews of the procedures used for data acquisition, processing and inversion of electrical resistivity data based on compilation of academic literature. In recent times there had been a significant evolution in field survey designs and data inversion techniques for the resistivity method. In general 2-D inversion for resistivity data is carried out using the linearized least-square method with the local optimization technique .Multi-electrode and multi-channel systems have made it possible to conduct large 2-D, 3-D and even 4-D surveys efficiently to resolve complex geological structures that were not possible with traditional 1-D surveys. 3-D surveys play an increasingly important role in very complex areas where 2-D models suffer from artifacts due to off-line structures. Continued developments in computation technology, as well as fast data inversion techniques and software, have made it possible to use optimization techniques to obtain model parameters to a higher accuracy. A brief discussion on the limitations of the electrical resistivity method has also been presented.Keywords: Resistivity, inversion, optimization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6086543 Enhancing Experiential Learning in a Smart Flipped Classroom: A Case Study
Authors: Fahri Benli, Sitalakshmi Venkatraman, Ye Wei, Fiona Wahr
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A flipped classroom which is a form of blended learning shifts the focus from a teacher-centered approach to a learner-centered approach. However, not all learners are ready to take the active role of knowledge and skill acquisition through a flipped classroom and they continue to delve in a passive mode of learning. This challenges educators in designing, scaffolding and facilitating in-class activities for students to have active learning experiences in a flipped classroom environment. Experiential learning theories have been employed by educators in the past in physical classrooms based on the principle that knowledge could be actively developed through direct experience. However, with more of online teaching witnessed recently, there are inherent limitations in designing and simulating an experiential learning activity for an online environment. In this paper, we explore enhancing experiential learning using smart digital tools that could be employed in a flipped classroom within a higher education setting. We present the use of smart collaborative tools online to enhance the experiential learning activity to teach higher-order cognitive concepts of business process modeling as a case study.
Keywords: Experiential learning, flipped classroom, smart software tools, online learning higher-order learning attributes.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 453542 Transient Stability Improvement in Multi-Machine System Using Power System Stabilizer (PSS) and Static Var Compensator (SVC)
Authors: Khoshnaw Khalid Hama Saleh, Ergun Ercelebi
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Increasingly complex modern power systems require stability, especially for transient and small disturbances. Transient stability plays a major role in stability during fault and large disturbance. This paper compares a power system stabilizer (PSS) and static Var compensator (SVC) to improve damping oscillation and enhance transient stability. The effectiveness of a PSS connected to the exciter and/or governor in damping electromechanical oscillations of isolated synchronous generator was tested. The SVC device is a member of the shunt FACTS (flexible alternating current transmission system) family, utilized in power transmission systems. The designed model was tested with a multi-machine system consisting of four machines six bus, using MATLAB/SIMULINK software. The results obtained indicate that SVC solutions are better than PSS.Keywords: FACTS, MATLAB/SIMULINK, multi-machine system, PSS, SVC, transient stability.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3385541 Design and Implementation of Quantum Cellular Automata Based Novel Adder Circuits
Authors: Santanu Santra, Utpal Roy
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The most important mathematical operation for any computing system is addition. An efficient adder can be of greater assistance in designing of any arithmetic circuits. Quantum-dot Cellular Automata (QCA) is a promising nanotechnology to create electronic circuits for computing devices and suitable candidate for next generation of computing systems. The article presents a modest approach to implement a novel XOR gate. The gate is simple in structure and powerful in terms of implementing digital circuits. By applying the XOR gate, the hardware requirement for a QCA circuit can be decrease and circuits can be simpler in level, clock phase and cell count. In order to verify the functionality of the proposed device some implementation of Half Adder (HA) and Full Adder (FA) is checked by means of computer simulations using QCA-Designer tool. Simulation results and physical relations confirm its usefulness in implementing every digital circuit.
Keywords: Clock, Computing system, Majority gate, QCA, QCA Designer.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4460540 Designing Transcutaneous Inductive Powering Links for Implanted Micro-System Device
Authors: Saad Mutashar Abbas, M. A. Hannan, S. A. Samad, A. Hussain
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This paper presented a proposed design for transcutaneous inductive powering links. The design used to transfer power and data to the implanted devices such as implanted Microsystems to stimulate and monitoring the nerves and muscles. The system operated with low band frequency 13.56 MHZ according to industrial- scientific – medical (ISM) band to avoid the tissue heating. For external part, the modulation index is 13 % and the modulation rate 7.3% with data rate 1 Mbit/s assuming Tbit=1us. The system has been designed using 0.35-μm fabricated CMOS technology. The mathematical model is given and the design is simulated using OrCAD P Spice 16.2 software tool and for real-time simulation the electronic workbench MULISIM 11 has been used. The novel circular plane (pancake) coils was simulated using ANSOFT- HFss software.Keywords: Implanted devices, ASK techniques, Class-E power amplifier, Inductive powering and low-frequency ISM band.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2606539 Energy Aware Adhoc On-demand Multipath Distance Vector Protocol for QoS Routing
Authors: J. Seetaram, P. Satish Kumar
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Mobile Adhoc Networks (MANETs) are infrastructure-less, dynamic network of collections of wireless mobile nodes communicating with each other without any centralized authority. A MANET is a mobile device of interconnections through wireless links, forming a dynamic topology. Routing protocols have a big role in data transmission across a network. Routing protocols, two major classifications are unipath and multipath. This study evaluates performance of an on-demand multipath routing protocol named Adhoc On-demand Multipath Distance Vector routing (AOMDV). This study proposes Energy Aware AOMDV (EAAOMDV) an extension of AOMDV which decreases energy consumed on a route.Keywords: Mobile Adhoc Network (MANET), unipath, multipath, Adhoc On-demand Multipath Distance Vector routing (AOMDV).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2131538 EMOES: Eye Motion and Ocular Expression Simulator
Authors: Nicoletta Adamo-Villani, Gerardo Beni, Jeremy White
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We introduce, a new interactive 3D simulation system of ocular motion and expressions suitable for: (1) character animation applications to game design, film production, HCI (Human Computer Interface), conversational animated agents, and virtual reality; (2) medical applications (ophthalmic neurological and muscular pathologies: research and education); and (3) real time simulation of unconscious cognitive and emotional responses (for use, e.g., in psychological research). The system is comprised of: (1) a physiologically accurate parameterized 3D model of the eyes, eyelids, and eyebrow regions; and (2) a prototype device for realtime control of eye motions and expressions, including unconsciously produced expressions, for application as in (1), (2), and (3) above. The 3D eye simulation system, created using state-of-the-art computer animation technology and 'optimized' for use with an interactive and web deliverable platform, is, to our knowledge, the most advanced/realistic available so far for applications to character animation and medical pedagogy.
Keywords: 3D animation, HCI, medical simulation, ocularmotion and expression.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1985537 Water Vapor Plasma Torch: Design, Characteristics and Applications
Authors: A. Tamošiūnas, P. Valatkevičius, V. Grigaitiene, V. Valinčius
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The atmospheric pressure plasma torch with a direct current arc discharge stabilized by water vapor vortex was experimentally investigated. Overheated up to 450K water vapor was used as plasma forming gas. Plasma torch design is one of the most important factors leading to a stable operation of the device. The electrical and thermal characteristics of the plasma torch were determined during the experimental investigations. The design and the basic characteristics of the water vapor plasma torch are presented in the paper. Plasma torches with the electric arc stabilized by water vapor vortex provide special performance characteristics in some plasma processing applications such as thermal plasma neutralization and destruction of organic wastes enabling to extract high caloric value synthesis gas as by-product of the process. Syngas could be used as a surrogate fuel partly replacing the dependence on the fossil fuels or used as a feedstock for hydrogen, methanol production.Keywords: Arc discharge, atmospheric pressure thermal plasma, plasma torch, water vapor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4498536 Simulations of Laminar Liquid Flows through Superhydrophobic Micro-Pipes
Authors: Mohamed E. Eleshaky
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This paper investigates the dynamic behavior of laminar water flows inside superhydrophobic micro-pipes patterned with square micro-posts features under different operating conditions. It also investigates the effects of air fraction and Reynolds number on the frictional performance of these pipes. Rather than modeling the air-water interfaces of superhydrophobic as a flat inflexible surface, a transient, incompressible, three-dimensional, volume-of-fluid (VOF) methodology has been employed to continuously track the air–water interface shape inside micro-pipes. Also, the entrance effects on the flow field have been taken into consideration. The results revealed the strong dependency of the frictional performance on the air fractions and Reynolds number. The frictional resistance reduction becomes increasingly more significant at large air fractions and low Reynolds numbers. Increasing Reynolds number has an adverse effect on the frictional resistance reduction.
Keywords: Drag reduction, laminar flow in micropipes, numerical simulation, superhyrophobic surfaces, microposts.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1955535 A Novel 14 nm Extended Body FinFET for Reduced Corner Effect, Self-Heating Effect, and Increased Drain Current
Authors: Cheng-Hsien Chang, Jyi-Tsong Lin, Po-Hsieh Lin, Hung-Pei Hsu, Chan-Hsiang Chang, Ming-Tsung Shih, Shih-Chuan Tseng, Min-Yan Lin
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In this paper, we have proposed a novel FinFET with extended body under the poly gate, which is called EB-FinFET, and its characteristic is demonstrated by using three-dimensional (3-D) numerical simulation. We have analyzed and compared it with conventional FinFET. The extended body height dependence on the drain induced barrier lowering (DIBL) and subthreshold swing (S.S) have been also investigated. According to the 3-D numerical simulation, the proposed structure has a firm structure, an acceptable short channel effect (SCE), a reduced series resistance, an increased on state drain current (I on) and a large normalized I DS. Furthermore, the structure can also improve corner effect and reduce self-heating effect due to the extended body. Our results show that the EBFinFET is excellent for nanoscale device.Keywords: SOI, FinFET, tri-gate, self-heating effect.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2808534 Numerical Investigation of Thermally Triggered Release Kinetics of Double Emulsion for Drug Delivery Using Phase Change Material
Authors: Yong Ren, Yaping Zhang
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A numerical model has been developed to investigate the thermally triggered release kinetics for drug delivery using phase change material as shell of microcapsules. Biocompatible material n-Eicosane is used as demonstration. PCM shell of microcapsule will remain in solid form after the drug is taken, so the drug will be encapsulated by the shell, and will not be released until the target body part of lesion is exposed to external heat source, which will thermally trigger the release kinetics, leading to solid-to-liquid phase change. The findings can lead to better understanding on the key effects influencing the phase change process for drug delivery applications. The facile approach to release drug from core/shell structure of microcapsule can be well integrated with organic solvent free fabrication of microcapsules, using double emulsion as template in microfluidic aqueous two phase system.
Keywords: Phase change material, drug release kinetics, double emulsion, microfluidics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2423533 3D Simulator of Ocular Motion and Expression
Authors: Nicoletta Adamo-Villani, Gerardo Beni, Jeremy White
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We introduce a new interactive 3D simulator of ocular motion and expressions suitable for: (1) character animation applications to game design, film production, HCI (Human Computer Interface), conversational animated agents, and virtual reality; (2) medical applications (ophthalmic neurological and muscular pathologies: research and education); and (3) real time simulation of unconscious cognitive and emotional responses (for use, e.g., in psychological research). Using state-of-the-art computer animation technology we have modeled and rigged a physiologically accurate 3D model of the eyes, eyelids, and eyebrow regions and we have 'optimized' it for use with an interactive and web deliverable platform. In addition, we have realized a prototype device for realtime control of eye motions and expressions, including unconsciously produced expressions, for application as in (1), (2), and (3) above. The 3D simulator of eye motion and ocular expression is, to our knowledge, the most advanced/realistic available so far for applications in character animation and medical pedagogy.
Keywords: 3D animation, HCI, medical simulation, ocularmotion and expression.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2233532 Voices and Pictures from an Online Course and a Face to Face Course
Authors: Eti Gilad, Shosh Millet
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In light of the technological development and its introduction into the field of education, an online course was designed in parallel to the 'conventional' course for teaching the ''Qualitative Research Methods''. This course aimed to characterize learning-teaching processes in a 'Qualitative Research Methods' course studied in two different frameworks. Moreover, its objective was to explore the difference between the culture of a physical learning environment and that of online learning. The research monitored four learner groups, a total of 72 students, for two years, two groups from the two course frameworks each year. The courses were obligatory for M.Ed. students at an academic college of education and were given by one female-lecturer. The research was conducted in the qualitative method as a case study in order to attain insights about occurrences in the actual contexts and sites in which they transpire. The research tools were open-ended questionnaire and reflections in the form of vignettes (meaningful short pictures) to all students as well as an interview with the lecturer. The tools facilitated not only triangulation but also collecting data consisting of voices and pictures of teaching and learning. The most prominent findings are: differences between the two courses in the change features of the learning environment culture for the acquisition of contents and qualitative research tools. They were manifested by teaching methods, illustration aids, lecturer's profile and students' profile.Keywords: Face to face course, online course, qualitative research, vignettes.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1713531 Remarks on Energy Based Control of a Nonlinear, Underactuated, MIMO and Unstable Benchmark
Authors: Guangyu Liu
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In the last decade, energy based control theory has undergone a significant breakthrough in dealing with underactated mechanical systems with two successful and similar tools, controlled Lagrangians and controlled Hamiltanians (IDA-PBC). However, because of the complexity of these tools, successful case studies are lacking, in particular, MIMO cases. The seminal theoretical paper of controlled Lagrangians proposed by Bloch and his colleagues presented a benchmark example–a 4 d.o.f underactuated pendulum on a cart but a detailed and completed design is neglected. To compensate this ignorance, the note revisit their design idea by addressing explicit control functions for a similar device motivated by a vector thrust body hovering in the air. To the best of our knowledge, this system is the first MIMO, underactuated example that is stabilized by using energy based tools at the courtesy of the original design idea. Some observations are given based on computer simulation.
Keywords: Controlled Lagrangian, Energy Shaping, Spherical Inverted Pendulum, Controlled Hamiltonian.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1385530 Impact of Height of Silicon Pillar on Vertical DG-MOSFET Device
Authors: K. E. Kaharudin, A. H. Hamidon, F. Salehuddin
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Vertical Double Gate (DG) Metal Oxide Semiconductor Field Effect Transistor (MOSFET) is believed to suppress various short channel effect problems. The gate to channel coupling in vertical DG-MOSFET are doubled, thus resulting in higher current density. By having two gates, both gates are able to control the channel from both sides and possess better electrostatic control over the channel. In order to ensure that the transistor possess a superb turn-off characteristic, the subs-threshold swing (SS) must be kept at minimum value (60-90mV/dec). By utilizing SILVACO TCAD software, an n-channel vertical DG-MOSFET was successfully designed while keeping the sub-threshold swing (SS) value as minimum as possible. From the observation made, the value of sub-threshold swing (SS) was able to be varied by adjusting the height of the silicon pillar. The minimum value of sub-threshold swing (SS) was found to be 64.7mV/dec with threshold voltage (VTH) of 0.895V. The ideal height of the vertical DG-MOSFET pillar was found to be at 0.265 µm.
Keywords: DG-MOSFET, pillar, SCE, vertical
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1931529 A Simulation Study of Bullwhip Effect in a Closed-Loop Supply Chain with Fuzzy Demand and Fuzzy Collection Rate under Possibility Constraints
Authors: Debabrata Das, Pankaj Dutta
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Along with forward supply chain organization needs to consider the impact of reverse logistics due to its economic advantage, social awareness and strict legislations. In this paper, we develop a system dynamics framework for a closed-loop supply chain with fuzzy demand and fuzzy collection rate by incorporating product exchange policy in forward channel and various recovery options in reverse channel. The uncertainty issues associated with acquisition and collection of used product have been quantified using possibility measures. In the simulation study, we analyze order variation at both retailer and distributor level and compare bullwhip effects of different logistics participants over time between the traditional forward supply chain and the closed-loop supply chain. Our results suggest that the integration of reverse logistics can reduce order variation and bullwhip effect of a closed-loop system. Finally, sensitivity analysis is performed to examine the impact of various parameters on recovery process and bullwhip effect.Keywords: Bullwhip Effect, Fuzzy Possibility Measures, Reverse Supply Chain, System Dynamics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2702528 Re-Examination of Louis Pasteur’s S-Shaped Flask Experiment
Authors: Ming-Hua Fu
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No negative control nor control to prevent microbes from escaping was set when the S-shaped flask experiments were performed by Pasteur. Microscope was not used to observe the media in the flasks. Louis Pasteur’s S-shaped flask experiment was re-examined by using U-shaped flasks, modified S-shaped flasks and microscope. A mixture of microbes was isolated from the room air, from which one rod-shaped Bacillus species with proposed name Bacillus gaso-mobilis sp nov and one grape-shaped Staphylococcus species with proposed name of Staphylococcus gaso-mobilis sp nov were identified. Their penicillin and ampicillin resistant strains containing plasmids were isolated. These bacteria could change color, produce odor and automatically move in the air. They did not form colonies on solid media. They had a high suspension capacity in liquid media. Their light absorbance peaked at the wave length of 320 nm. It was concluded that there were flaws with Louis Pasteur’s S-shaped flask experiments.
Keywords: Bacteria, gaso-mobile, re-examine, S-shaped flasks.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2837527 Modeling of Gas Turbine Cooled Blades
Authors: A. Pashayev, D. Askerov, R. Sadiqov, A. Samedov, C. Ardil
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In contrast to existing methods which do not take into account multiconnectivity in a broad sense of this term, we develop mathematical models and highly effective combination (BIEM and FDM) numerical methods of calculation of stationary and quasi-stationary temperature field of a profile part of a blade with convective cooling (from the point of view of realization on PC). The theoretical substantiation of these methods is proved by appropriate theorems. For it, converging quadrature processes have been developed and the estimations of errors in the terms of A.Ziqmound continuity modules have been received. For visualization of profiles are used: the method of the least squares with automatic conjecture, device spline, smooth replenishment and neural nets. Boundary conditions of heat exchange are determined from the solution of the corresponding integral equations and empirical relationships. The reliability of designed methods is proved by calculation and experimental investigations heat and hydraulic characteristics of the gas turbine first stage nozzle blade.Keywords: Gas turbine, cooled blade, nozzle blade, temperature field.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 621526 Metal(loids) Speciation Using HPLC-ICP-MS Technique in Klodnica River, Upper Silesia, Poland
Authors: Magdalena Jabłońska-Czapla
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The work allowed gaining knowledge about redox and speciation changes of As, Cr and Sb ionic forms in Klodnica River water. This kind of studies never has been conducted in this region of Poland. In study optimized and validated previously HPLC-ICP-MS methods for determination of As, Sb and Cr was used. Separation step was done using high-performance liquid chromatograph equipped with ion-exchange column followed by ICP-MS spectrometer detector. Preliminary studies included determination of the total concentration of As, Sb and Cr, pH, Eh, temperature and conductivity of the water samples. The study was conducted monthly from March to August 2014, at six points on the Klodnica River. The results indicate that exceeded at acceptable concentration of total Cr and Sb was observed in Klodnica River and we should qualify Klodnica River waters below the second purity class. In Klodnica River waters dominates oxidized antimony and arsenic forms, as well as the two forms of chromium Cr(VI) and Cr(III). Studies have also shown the methyl derivative of arsenic's presence.
Keywords: Antimony, arsenic, chromium, HPLC-ICP-MS, river water, speciation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2139525 Investigation of Shear Thickening Liquid Protection Fibrous Material
Authors: Po-Yun Chen, Jui-Liang Yen, Chang-Ping Chang, Wen-Hua Hu, Yu-Liang Chen, Yih-Ming Liu, Chin-Yi Chou, Ming-Der Ger
Abstract:
The stab resistance performance of newly developed fabric composites composed of hexagonal paper honeycombs, filled with shear thickening fluid (STF), and woven Kevlar® fabric or UHMPE was investigated in this study. The STF was prepared by dispersing submicron SiO2 particles into polyethylene glycol (PEG). Our results indicate that the STF-Kevlar composite possessed lower penetration depth than that of neat Kevlar. In other words, the STF-Kevlar composite can attain the same energy level in stab-resistance test with fewer layers of Kevlar fabrics than that of the neat Kevlar fabrics. It also indicates that STF can be used for the fabrication of flexible body armors and can provide improved protection against stab threats. We found that the stab resistance of the STF-Kevlar composite increases with the increase of SiO2 concentration in STF. Moreover, the silica particles functionalized with silane coupling agent can further improve the stab resistance.Keywords: shear thickening fluid, SiO2, Kevlar, stab
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3303524 Improvement in Silicon on Insulator Devices using Strained Si/SiGe Technology for High Performance in RF Integrated Circuits
Authors: Morteza Fathipour, Samira Omidbakhsh, Kimia Khodayari
Abstract:
RF performance of SOI CMOS device has attracted significant amount of interest recently. In order to improve RF parameters, Strained Si/Relaxed Si0.8Ge0.2 investigated as a replacement for Si technology .Enhancement of carrier mobility associated with strain engineering makes Strained Si a promising candidate for improving RF performance of CMOS technology. From the simulation, the cut-off frequency is estimated to be 224 GHZ, whereas in SOI at similar bias is about 188 GHZ. Therefore, Strained Si exhibits 19% improvement in cut-off frequency over similar Si counterpart. In this paper, Ion/Ioff ratio is studied as one of the key parameters in logic and digital application. Strained Si/SiGe demonstrates better Ion/Ioff characteristic than SOI, in similar channel length of 100 nm.Another important key analog figures of merit such as Early Voltage (VEA) ,transconductance vs drain current (gm /Ids) are studied. They introduce the efficiency of the devices to convert dc power into ac frequency.Keywords: cut-off frequency, RF application, Silicon oninsulator, Strained Si/SiGe on insulator.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1745523 Hydrogen Permeability of BSCY Proton-Conducting Perovskite Membrane
Authors: M. Heidari, A. Safekordi, A. Zamaniyan, E. Ganji Babakhani, M. Amanipour
Abstract:
Perovskite-type membrane Ba0.5Sr0.5Ce0.9Y0.1O3-δ (BSCY) was successfully synthesized by liquid citrate method. The hydrogen permeation and stability of BSCY perovskite-type membranes were studied at high temperatures. The phase structure of the powder was characterized by X-ray diffraction (XRD). Scanning electron microscopy (SEM) was used to characterize microstructures of the membrane sintered under various conditions. SEM results showed that increasing in sintering temperature, formed dense membrane with clear grains. XRD results for BSCY membrane that sintered in 1150 °C indicated single phase perovskite structure with orthorhombic configuration, and SEM results showed dense structure with clear grain size which is suitable for permeation tests. Partial substitution of Sr with Ba in SCY structure improved the hydrogen permeation flux through the membrane due to the larger ionic radius of Ba2+. BSCY membrane shows high hydrogen permeation flux of 1.6 ml/min.cm2 at 900 °C and partial pressure of 0.6.
Keywords: Hydrogen separation, perovskite, proton conducting membrane.
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