Search results for: continuous dynamic recrystallization
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6050

Search results for: continuous dynamic recrystallization

4040 Comparison between Classical and New Direct Torque Control Strategies of Induction Machine

Authors: Mouna Essaadi, Mohamed Khafallah, Abdallah Saad, Hamid Chaikhy

Abstract:

This paper presents a comparative analysis between conventional direct torque control (C_DTC), Modified direct torque control (M_DTC) and twelve sectors direct torque control (12_DTC).Those different strategies are compared by simulation in term of torque, flux and stator current performances. Finally, a summary of the comparative analysis is presented.

Keywords: C_DTC, M_DTC, 12_DTC, torque dynamic, stator current, flux, performances

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4039 Tectonic Movements and Ecosystems

Authors: Arvind Kumar Trivedi

Abstract:

Our Earth is dynamic in nature and its structure behaves like a puzzle because the interior of the Earth is in both gaseous as well as molten (liquid) form and the crust i.e. the outermost surface is in solid form. This Earth was one landmass known as ‘Pangaea’ in the beginning. With time due to complex phenomena of tectonic movements, it was broken into various landmasses along with water bodies. This Pangaea was in direct contact with the atmosphere playing dominant role in creating various ecosystems on the Earth. Ecosystems mean: Eco (environment body) and systems (interdependent complex of all the organisms interacting with each other). This paper provides an in-depth discussion on tectonic movements as well as ecosystems & how these two affect each other and in the end, we will enlist various methods on how to preserve our ‘Mother Earth’.

Keywords: tectonic movements, ecosystems, plate tectonics, impact

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4038 A Portable Device for Pulse Wave Velocity Measurements

Authors: Chien-Lin Wang, Cha-Ling Ko, Tainsong Chen

Abstract:

Pulse wave velocity (PWV) of blood flow provides important information of vessel property and blood pressure which can be used to assess cardiovascular disease. However, the above measurements need expensive equipment, such as Doppler ultrasound, MRI, angiography etc. The photoplethysmograph (PPG) signals are commonly utilized to detect blood volume changes. In this study, two infrared (IR) probes are designed and placed at a fixed distance from finger base and fingertip. An analog circuit with automatic gain adjustment is implemented to get the stable original PPG signals from above two IR probes. In order to obtain the time delay precisely between two PPG signals, we obtain the pulse transit time from the second derivative of the original PPG signals. To get a portable, wireless and low power consumption PWV measurement device, the low energy Bluetooth 4.0 (BLE) and the microprocessor (Cortex™-M3) are used in this study. The PWV is highly correlated with blood pressure. This portable device has potential to be used for continuous blood pressure monitoring.

Keywords: pulse wave velocity, photoplethysmography, portable device, biomedical engineering

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4037 Restoration of Railway Turnout Frog with FCAW

Authors: D. Sergejevs, A. Tipainis, P. Gavrilovs

Abstract:

Railway turnout frogs restored with MMA often have such defects as infusions, pores, a.o., which under the influence of dynamic forces cause premature destruction of the restored surfaces. To prolong the operational time of turnout frog, i.e. operational time of the restored surface, turnout frog was restored using FCAW and afterwards matallographic examination was performed. Experimental study revealed that railway turnout frog restored with FCAW had better quality than elements restored with MMA, furthermore it provided considerable time economy.

Keywords: elements of railway turnout, FCAW, metallographic examination, quality of build-up welding

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4036 A Comparative Study of School Choice: China and the United States

Authors: Huizi Zeng

Abstract:

This paper delineates the historical retrospective and current status of school choice in China. Focusing on analyzing the similarities and differences in origin, evolution, public dispute, policy dynamics between China and the United States, the article depicts a panorama and explores possible causes. Both China and the United States continue to learn from historical legacy and invent new programs to perfect school choice policy but the outcomes are so different. On the one hand, the percentage of public schools in China remains high all along, while there is a considerably significant reduction in the United States. On the other hand, there is more governmental intervention in the United States with continuous and constant policy updates and adjustment. Finally, this article adopts public-private partnerships (PPP) to seek to provide insights into differences between the two countries and argue that school choice is not only the production of education marketization and corporation but also driven by political mechanism.

Keywords: China, United States, school choice, comparative analysis, policy, public private partnerships

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4035 Durability Analysis of a Knuckle Arm Using VPG System

Authors: Geun-Yeon Kim, S. P. Praveen Kumar, Kwon-Hee Lee

Abstract:

A steering knuckle arm is the component that connects the steering system and suspension system. The structural performances such as stiffness, strength, and durability are considered in its design process. The former study suggested the lightweight design of a knuckle arm considering the structural performances and using the metamodel-based optimization. The six shape design variables were defined, and the optimum design was calculated by applying the kriging interpolation method. The finite element method was utilized to predict the structural responses. The suggested knuckle was made of the aluminum Al6082, and its weight was reduced about 60% in comparison with the base steel knuckle, satisfying the design requirements. Then, we investigated its manufacturability by performing foraging analysis. The forging was done as hot process, and the product was made through two-step forging. As a final step of its developing process, the durability is investigated by using the flexible dynamic analysis software, LS-DYNA and the pre and post processor, eta/VPG. Generally, a car make does not provide all the information with the part manufacturer. Thus, the part manufacturer has a limit in predicting the durability performance with the unit of full car. The eta/VPG has the libraries of suspension, tire, and road, which are commonly used parts. That makes a full car modeling. First, the full car is modeled by referencing the following information; Overall Length: 3,595mm, Overall Width: 1,595mm, CVW (Curve Vehicle Weight): 910kg, Front Suspension: MacPherson Strut, Rear Suspension: Torsion Beam Axle, Tire: 235/65R17. Second, the road is selected as the cobblestone. The road condition of the cobblestone is almost 10 times more severe than that of usual paved road. Third, the dynamic finite element analysis using the LS-DYNA is performed to predict the durability performance of the suggested knuckle arm. The life of the suggested knuckle arm is calculated as 350,000km, which satisfies the design requirement set up by the part manufacturer. In this study, the overall design process of a knuckle arm is suggested, and it can be seen that the developed knuckle arm satisfies the design requirement of the durability with the unit of full car. The VPG analysis is successfully performed even though it does not an exact prediction since the full car model is very rough one. Thus, this approach can be used effectively when the detail to full car is not given.

Keywords: knuckle arm, structural optimization, Metamodel, forging, durability, VPG (Virtual Proving Ground)

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4034 SPICE Modeling for Evaluation of Distribution System Reliability Indices

Authors: G. N. Srinivas, K. Raju

Abstract:

This paper presents Markov processes for determining the reliability indices of distribution system. The continuous Markov modeling is applied to a complex radial distribution system and electrical equivalent circuits are developed for the modeling. In general PSPICE is being used for electrical and electronic circuits and various applications of power system like fault analysis, transient analysis etc. In this paper, the SPICE modeling equivalent circuits which are developed are applied in a novel way to Distribution System reliability analysis. These circuits are simulated using PSPICE software to obtain the state probabilities, the basic and performance indices. Thus the basic indices and the performance indices obtained by this method are compared with those obtained by FMEA technique. The application of the concepts presented in this paper are illustrated and analyzed for IEEE-Roy Billinton Test System (RBTS).

Keywords: distribution system, Markov Model, reliability indices, spice simulation

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4033 An Object-Oriented Modelica Model of the Water Level Swell during Depressurization of the Reactor Pressure Vessel of the Boiling Water Reactor

Authors: Rafal Bryk, Holger Schmidt, Thomas Mull, Ingo Ganzmann, Oliver Herbst

Abstract:

Prediction of the two-phase water mixture level during fast depressurization of the Reactor Pressure Vessel (RPV) resulting from an accident scenario is an important issue from the view point of the reactor safety. Since the level swell may influence the behavior of some passive safety systems, it has been recognized that an assumption which at the beginning may be considered as a conservative one, not necessary leads to a conservative result. This paper discusses outcomes obtained during simulations of the water dynamics and heat transfer during sudden depressurization of a vessel filled up to a certain level with liquid water under saturation conditions and with the rest of the vessel occupied by saturated steam. In case of the pressure decrease e.g. due to the main steam line break, the liquid water evaporates abruptly, being a reason thereby, of strong transients in the vessel. These transients and the sudden emergence of void in the region occupied at the beginning by liquid, cause elevation of the two-phase mixture. In this work, several models calculating the water collapse and swell levels are presented and validated against experimental data. Each of the models uses different approach to calculate void fraction. The object-oriented models were developed with the Modelica modelling language and the OpenModelica environment. The models represent the RPV of the Integral Test Facility Karlstein (INKA) – a dedicated test rig for simulation of KERENA – a new Boiling Water Reactor design of Framatome. The models are based on dynamic mass and energy equations. They are divided into several dynamic volumes in each of which, the fluid may be single-phase liquid, steam or a two-phase mixture. The heat transfer between the wall of the vessel and the fluid is taken into account. Additional heat flow rate may be applied to the first volume of the vessel in order to simulate the decay heat of the reactor core in a similar manner as it is simulated at INKA. The comparison of the simulations results against the reference data shows a good agreement.

Keywords: boiling water reactor, level swell, Modelica, RPV depressurization, thermal-hydraulics

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4032 Spatial Econometric Approaches for Count Data: An Overview and New Directions

Authors: Paula Simões, Isabel Natário

Abstract:

This paper reviews a number of theoretical aspects for implementing an explicit spatial perspective in econometrics for modelling non-continuous data, in general, and count data, in particular. It provides an overview of the several spatial econometric approaches that are available to model data that are collected with reference to location in space, from the classical spatial econometrics approaches to the recent developments on spatial econometrics to model count data, in a Bayesian hierarchical setting. Considerable attention is paid to the inferential framework, necessary for structural consistent spatial econometric count models, incorporating spatial lag autocorrelation, to the corresponding estimation and testing procedures for different assumptions, to the constrains and implications embedded in the various specifications in the literature. This review combines insights from the classical spatial econometrics literature as well as from hierarchical modeling and analysis of spatial data, in order to look for new possible directions on the processing of count data, in a spatial hierarchical Bayesian econometric context.

Keywords: spatial data analysis, spatial econometrics, Bayesian hierarchical models, count data

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4031 Performance Evaluation of Various Displaced Left Turn Intersection Designs

Authors: Hatem Abou-Senna, Essam Radwan

Abstract:

With increasing traffic and limited resources, accommodating left-turning traffic has been a challenge for traffic engineers as they seek balance between intersection capacity and safety; these are two conflicting goals in the operation of a signalized intersection that are mitigated through signal phasing techniques. Hence, to increase the left-turn capacity and reduce the delay at the intersections, the Florida Department of Transportation (FDOT) moves forward with a vision of optimizing intersection control using innovative intersection designs through the Transportation Systems Management & Operations (TSM&O) program. These alternative designs successfully eliminate the left-turn phase, which otherwise reduces the conventional intersection’s (CI) efficiency considerably, and divide the intersection into smaller networks that would operate in a one-way fashion. This study focused on the Crossover Displaced Left-turn intersections (XDL), also known as Continuous Flow Intersections (CFI). The XDL concept is best suited for intersections with moderate to high overall traffic volumes, especially those with very high or unbalanced left turn volumes. There is little guidance on determining whether partial XDL intersections are adequate to mitigate the overall intersection condition or full XDL is always required. The primary objective of this paper was to evaluate the overall intersection performance in the case of different partial XDL designs compared to a full XDL. The XDL alternative was investigated for 4 different scenarios; partial XDL on the east-west approaches, partial XDL on the north-south approaches, partial XDL on the north and east approaches and full XDL on all 4 approaches. Also, the impact of increasing volume on the intersection performance was considered by modeling the unbalanced volumes with 10% increment resulting in 5 different traffic scenarios. The study intersection, located in Orlando Florida, is experiencing recurring congestion in the PM peak hour and is operating near capacity with volume to a capacity ratio closer to 1.00 due to the presence of two heavy conflicting movements; southbound and westbound. The results showed that a partial EN XDL alternative proved to be effective and compared favorably to a full XDL alternative followed by the partial EW XDL alternative. The analysis also showed that Full, EW and EN XDL alternatives outperformed the NS XDL and the CI alternatives with respect to the throughput, delay and queue lengths. Significant throughput improvements were remarkable at the higher volume level with percent increase in capacity of 25%. The percent reduction in delay for the critical movements in the XDL scenarios compared to the CI scenario ranged from 30-45%. Similarly, queue lengths showed percent reduction in the XDL scenarios ranging from 25-40%. The analysis revealed how partial XDL design can improve the overall intersection performance at various demands, reduce the costs associated with full XDL and proved to outperform the conventional intersection. However, partial XDL serving low volumes or only one of the critical movements while other critical movements are operating near or above capacity do not provide significant benefits when compared to the conventional intersection.

Keywords: continuous flow intersections, crossover displaced left-turn, microscopic traffic simulation, transportation system management and operations, VISSIM simulation model

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4030 Development of a New Device for Bending Fatigue Testing

Authors: B. Mokhtarnia, M. Layeghi

Abstract:

This work presented an original bending fatigue-testing setup for fatigue characterization of composite materials. A three-point quasi-static setup was introduced that was capable of applying stress control load in different loading waveforms, frequencies, and stress ratios. This setup was equipped with computerized measuring instruments to evaluate fatigue damage mechanisms. A detailed description of its different parts and working features was given, and dynamic analysis was done to verify the functional accuracy of the device. Feasibility was validated successfully by conducting experimental fatigue tests.

Keywords: bending fatigue, quasi-static testing setup, experimental fatigue testing, composites

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4029 On Regional Climate Singularity: On Example of the Territory of Georgia

Authors: T. Davitashvili

Abstract:

In this paper, some results of numerical simulation of the air flow dynamics in the troposphere over the Caucasus Mountains taking place in conditions of nonstationarity of large-scale undisturbed background flow are presented. Main features of the atmospheric currents changeability while air masses are transferred from the Black Sea to the land’s surface had been investigated. In addition, the effects of thermal and advective-dynamic factors of atmosphere on the changes of the West Georgian climate have been studied. It was shown that non-proportional warming of the Black Sea and Colkhi lowland provokes the intensive strengthening of circulation and effect of climate cooling in the western Georgia.

Keywords: regional climate, numerical simulation, local circulation, orographic effect

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4028 Study on Pedestrian Street Reconstruction under Comfortable Continuous View: Take the Walking Streets of Zhengzhou City as an Example

Authors: Liu Mingxin

Abstract:

Streets act as the organizers of each image element on the urban spatial route, and the spatial continuity of urban streets is the basis for people to perceive the overall image of the city. This paper takes the walking space of Zhengzhou city as the research object, conducts investigation and analysis through questionnaire interviews, and selects typical walking space for in-depth study. Through the analysis of questionnaire data, the investigation and analysis of the current situation of walking space, and the analysis of pedestrian psychological behavior activities, the paper summarizes the construction suggestions of urban walking space continuity from the three aspects of the composition of walking street, the bottom interface and side interface, and the service facilities of walking space. The walking space is not only the traffic space but also the comfortable experience and the continuity of the space.

Keywords: walking space, spatial continuity, walking psychology, space reconstruction

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4027 Dynamics Pattern of Land Use and Land Cover Change and Its Driving Factors Based on a Cellular Automata Markov Model: A Case Study at Ibb Governorate, Yemen

Authors: Abdulkarem Qasem Dammag, Basema Qasim Dammag, Jian Dai

Abstract:

Change in Land use and Land cover (LU/LC) has a profound impact on the area's natural, economic, and ecological development, and the search for drivers of land cover change is one of the fundamental issues of LU/LC change. The study aimed to assess the temporal and Spatio-temporal dynamics of LU/LC in the past and to predict the future using Landsat images by exploring the characteristics of different LU/LC types. Spatio-temporal patterns of LU/LC change in Ibb Governorate, Yemen, were analyzed based on RS and GIS from 1990, 2005, and 2020. A socioeconomic survey and key informant interviews were used to assess potential drivers of LU/LC. The results showed that from 1990 to 2020, the total area of vegetation land decreased by 5.3%, while the area of barren land, grassland, built-up area, and waterbody increased by 2.7%, 1.6%, 1.04%, and 0.06%, respectively. Based on socio-economic surveys and key informant interviews, natural factors had a significant and long-term impact on land change. In contrast, site construction and socio-economic factors were the main driving forces affecting land change in a short time scale. The analysis results have been linked to the CA-Markov Land Use simulation and forecasting model for the years 2035 and 2050. The simulation results revealed from the period 2020 to 2050, the trend of dynamic changes in land use, where the total area of barren land decreased by 7.0% and grassland by 0.2%, while the vegetation land, built-up area, and waterbody increased by 4.6%, 2.6%, and 0.1 %, respectively. Overall, these findings provide LULC's past and future trends and identify drivers, which can play an important role in sustainable land use planning and management by balancing and coordinating urban growth and land use and can also be used at the regional level in different levels to provide as a reference. In addition, the results provide scientific guidance to government departments and local decision-makers in future land-use planning through dynamic monitoring of LU/LC change.

Keywords: LU/LC change, CA-Markov model, driving forces, change detection, LU/LC change simulation

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4026 Specialized Building Terminology of the 19th Century

Authors: Klara Kroftova, Martin Ebel

Abstract:

Human history is characterized by continuous evolution. As mankind developed, so did crafts, doctrine, and, of course, language. Each field of human activity, science, and art or architecture has its own vocabulary, terms with its specific, well-defined meaning. These are words or phrases that may have a general meaning in a certain context, but which, when used in specific contexts, are characterized by their expertise. The development of architecture in this area is, therefore, closely related to the development of architecture. People discovered new building materials, building constructions, decorating, furnishings, etc. and with each new knowledge came a new name. Architecture and construction were specific to individual nations, but throughout human history, they were also copied differently from other nations. Thus, the terminology of the Czech language was established, but also adopted from foreign languages. In this paper, we will focus on the linguistic analysis of terms that we most often encounter in the study of 19th-century architecture in the Austro-Hungarian Monarchy. The article is supplemented by a small picture dictionary.

Keywords: tenement houses, 19th century, terminology, Austro-Hungarian monarchy

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4025 Greek Teachers' Understandings of Typical Language Development and of Language Difficulties in Primary School Children and Their Approaches to Language Teaching

Authors: Konstantina Georgali

Abstract:

The present study explores Greek teachers’ understandings of typical language development and of language difficulties. Its core aim was to highlight that teachers need to have a thorough understanding of educational linguistics, that is of how language figures in education. They should also be aware of how language should be taught so as to promote language development for all students while at the same time support the needs of children with language difficulties in an inclusive ethos. The study, thus argued that language can be a dynamic learning mechanism in the minds of all children and a powerful teaching tool in the hands of teachers and provided current research evidence to show that structural and morphological particularities of native languages- in this case, of the Greek language- can be used by teachers to enhance children’s understanding of language and simultaneously improve oral language skills for children with typical language development and for those with language difficulties. The research was based on a Sequential Exploratory Mixed Methods Design deployed in three consecutive and integrative phases. The first phase involved 18 exploratory interviews with teachers. Its findings informed the second phase involving a questionnaire survey with 119 respondents. Contradictory questionnaire results were further investigated in a third phase employing a formal testing procedure with 60 children attending Y1, Y2 and Y3 of primary school (a research group of 30 language impaired children and a comparison group of 30 children with typical language development, both identified by their class teachers). Results showed both strengths and weaknesses in teachers’ awareness of educational linguistics and of language difficulties. They also provided a different perspective of children’s language needs and of language teaching approaches that reflected current advances and conceptualizations of language problems and opened a new window on how best they can be met in an inclusive ethos. However, teachers barely used teaching approaches that could capitalize on the particularities of the Greek language to improve language skills for all students in class. Although they seemed to realize the importance of oral language skills and their knowledge base on language related issues was adequate, their practices indicated that they did not see language as a dynamic teaching and learning mechanism that can promote children’s language development and in tandem, improve academic attainment. Important educational implications arose and clear indications of the generalization of findings beyond the Greek educational context.

Keywords: educational linguistics, inclusive ethos, language difficulties, typical language development

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4024 Implementation of 4-Bit Direct Charge Transfer Switched Capacitor DAC with Mismatch Shaping Technique

Authors: Anuja Askhedkar, G. H. Agrawal, Madhu Gudgunti

Abstract:

Direct Charge Transfer Switched Capacitor (DCT-SC) DAC is the internal DAC used in Delta-Sigma (∆∑) DAC which works on Over-Sampling concept. The Switched Capacitor DAC mainly suffers from mismatch among capacitors. Mismatch among capacitors in DAC, causes non linearity between output and input. Dynamic Element Matching (DEM) technique is used to match the capacitors. According to element selection logic there are many types. In this paper, Data Weighted Averaging (DWA) technique is used for mismatch shaping. In this paper, the 4 bit DCT-SC-DAC with DWA-DEM technique is implemented using WINSPICE simulation software in 180nm CMOS technology. DNL for DAC with DWA is ±0.03 LSB and INL is ± 0.02LSB.

Keywords: ∑-Δ DAC, DCT-SC-DAC, mismatch shaping, DWA, DEM

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4023 Stochastic Repair and Replacement with a Single Repair Channel

Authors: Mohammed A. Hajeeh

Abstract:

This paper examines the behavior of a system, which upon failure is either replaced with certain probability p or imperfectly repaired with probability q. The system is analyzed using Kolmogorov's forward equations method; the analytical expression for the steady state availability is derived as an indicator of the system’s performance. It is found that the analysis becomes more complex as the number of imperfect repairs increases. It is also observed that the availability increases as the number of states and replacement probability increases. Using such an approach in more complex configurations and in dynamic systems is cumbersome; therefore, it is advisable to resort to simulation or heuristics. In this paper, an example is provided for demonstration.

Keywords: repairable models, imperfect, availability, exponential distribution

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4022 Comics as Third Space: An Analysis of the Continuous Negotiation of Identities in Postcolonial Philippines

Authors: Anna Camille V. Flores

Abstract:

Comics in the Philippines has taken on many uses for the Filipino people. They have been sources of entertainment, education, and political and social commentaries. History has been witnessed to the rise and fall of Philippine comics but the 21st century is seeing a revival of the medium and the industry. It is within this context that an inquiry about Filipino identity is situated. Employing the analytical framework of postcolonialism, particularly Homi K. Bhabha’s concepts of Hybridity and the Third Space, this study analyzes three contemporary Philippine comics, Trese, Filipino Heroes League, and Dead Balagtas. The study was able to draw three themes that represent how Filipinos inhabit hybrid worlds and hybridized identities. First, the third space emerged through the use of hybrid worlds in the comics. Second, (re)imagined communities are established through the use of intertextual signifiers. Third, (re)negotiated identities are expressed through visual and narrative devices such as the use of Philippine mythology, historical and contemporary contexts, and language. In conclusion, comics can be considered as Third Space where these identities have the agency and opportunity to be expressed and represented.

Keywords: comics, hybridity and third space, Philippine comics, postcolonialism

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4021 The SEMONT Monitoring and Risk Assessment of Environmental EMF Pollution

Authors: Dragan Kljajic, Nikola Djuric, Karolina Kasas-Lazetic, Danka Antic

Abstract:

Wireless communications have been expanded very fast in recent decades. This technology relies on an extensive network of base stations and antennas, using radio frequency signals to transmit information. Devices that use wireless communication, while offering various services, basically act as sources of non-ionizing electromagnetic fields (EMF). Such devices are permanently present in the human vicinity and almost constantly radiate, causing EMF pollution of the environment. This fact has initiated development of modern systems for observation of the EMF pollution, as well as for risk assessment. This paper presents the Serbian electromagnetic field monitoring network – SEMONT, designed for automated, remote and continuous broadband monitoring of EMF in the environment. Measurement results of the SEMONT monitoring at one of the test locations, within the main campus of the University of Novi Sad, are presented and discussed, along with corresponding exposure assessment of the general population, regarding the Serbian legislation.

Keywords: EMF monitoring, exposure assessment, sensor nodes, wireless network

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4020 Optimizing Microgrid Operations: A Framework of Adaptive Model Predictive Control

Authors: Ruben Lopez-Rodriguez

Abstract:

In a microgrid, diverse energy sources (both renewable and non-renewable) are combined with energy storage units to form a localized power system. Microgrids function as independent entities, capable of meeting the energy needs of specific areas or communities. This paper introduces a Model Predictive Control (MPC) approach tailored for grid-connected microgrids, aiming to optimize their operation. The formulation employs Mixed-Integer Programming (MIP) to find optimal trajectories. This entails the fulfillment of continuous and binary constraints, all while accounting for commutations between various operating conditions such as storage unit charge/discharge, import/export from/towards the main grid, as well as asset connection/disconnection. To validate the proposed approach, a microgrid case study is conducted, and the simulation results are compared with those obtained using a rule-based strategy.

Keywords: microgrids, mixed logical dynamical systems, mixed-integer optimization, model predictive control

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4019 Issues in Travel Demand Forecasting

Authors: Huey-Kuo Chen

Abstract:

Travel demand forecasting including four travel choices, i.e., trip generation, trip distribution, modal split and traffic assignment constructs the core of transportation planning. In its current application, travel demand forecasting has associated with three important issues, i.e., interface inconsistencies among four travel choices, inefficiency of commonly used solution algorithms, and undesirable multiple path solutions. In this paper, each of the three issues is extensively elaborated. An ideal unified framework for the combined model consisting of the four travel choices and variable demand functions is also suggested. Then, a few remarks are provided in the end of the paper.

Keywords: travel choices, B algorithm, entropy maximization, dynamic traffic assignment

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4018 Design of Collaborative Web System: Based on Case Study of PBL Support Systems

Authors: Kawai Nobuaki

Abstract:

This paper describes the design and implementation of web system for continuable and viable collaboration. This study proposes the improvement of the system based on a result of a certain practice. As contemporary higher education information environments transform, this study highlights the significance of university identity and college identity that are formed continuously through independent activities of the students. Based on these discussions, the present study proposes a practical media environment design which facilitates the processes of organizational identity formation based on a continuous and cyclical model. Even if users change by this system, the communication system continues operation and cooperation. The activity becomes the archive and produces new activity. Based on the result, this study elaborates a plan with a re-design by a system from the viewpoint of second-order cybernetics. Systems theory is a theoretical foundation for our study.

Keywords: collaborative work, learning management system, second-order cybernetics, systems theory, user generated contents, viable system model

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4017 Effect of Motor Imagery of Truncal Exercises on Trunk Function and Balance in Early Stroke: A Randomized Controlled Trial

Authors: Elsa Reethu, S. Karthik Babu, N. Syed

Abstract:

Background: Studies in the past focused on the additional benefits of action observation in improving upper and lower limb functions and improving activities of daily living when administered along with conventional therapy. Nevertheless, there is a paucity of literature proving the effects of motor imagery of truncal exercise in improving trunk control in patients with stroke. Aims/purpose: To study the effect of motor imagery of truncal exercises on trunk function and balance in early stroke. Methods: A total of 24 patients were included in the study. 12 were included in the experimental group and 12 were included in control group Trunk function was measured using Trunk Control Test (TCT), Trunk Impairment Scale Verheyden (TIS Verheyden) and Trunk Impairment Scale Fujiwara (TIS Fujiwara). The balance was assessed using Brunel Balance Assessment (BBA) and Tinetti POMA. For the experimental group, each session was for 30 minutes of physical exercises and 15 minutes of motor imagery, once a day, six times a week for 3 weeks and prior to the exercise session, patients viewed a video tape of all the trunk exercises to be performed for 15minutes. The control group practiced the trunk exercises alone for the same duration. Measurements were taken before, after and 4 weeks after intervention. Results: The effect of treatment in motor imagery group showed better improvement when compared with control group when measured after 3 weeks on values of static sitting balance, dynamic balance, total TIS (Verheyden) score, BBA, Tinetti balance and gait with a large effect size of 0.86, 1.99, 1.69, 1.06, 1.63 and 0.97 respectively. The moderate effect size was seen in values of TIS Fujiwara (0.58) and small effect size was seen on TCT (0.12) and TIS coordination component (0.13).at the end of 4 weeks after intervention, the large effect size was identified on values of dynamic balance (2.06), total TIS score (1.59) and Tinetti balance (1.24). The moderate effect size was observed on BBA (0.62) and Tinetti gait (0.72). Conclusion: Trunk motor imagery is effective in improving trunk function and balance in patients with stroke and has a carryover effect in the aspects of mobility. The therapy gain that was observed during the time of discharge was seen to be maintained at the follow-up levels.

Keywords: stroke, trunk rehabilitation, trunk function, balance, motor imagery

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4016 Mechanisms of Cultural Change Resistance through Cultures

Authors: Horaya Mostafa Ahmed

Abstract:

All cultures are inherently predisposed to change and, at the same time, to resisting change. There are dynamic processes operating that encourage the acceptance of new ideas and things, while there are others that encourage changeless stability. Despite the dramatic changes that have taken place in all human cultures, there are cultures still steadfast and resist change. These cultures resist through some culture mechanisms like, cultural boundaries, ethnocentrism, religion, and cultural relativity. So this paper is an attempt to discover these mechanisms of cultural change resistance and to ask is cultural change always required.

Keywords: cultural change, cultural boundaries, cultural relativity, ethnocentrism, religion, resistance

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4015 Explosion Mechanics of Aluminum Plates Subjected to the Combined Effect of Blast Wave and Fragment Impact Loading: A Multicase Computational Modeling Study

Authors: Atoui Oussama, Maazoun Azer, Belkassem Bachir, Pyl Lincy, Lecompte David

Abstract:

For many decades, researchers have been focused on understanding the dynamic behavior of different structures and materials subjected to fragment impact or blast loads separately. The explosion mechanics, as well as the impact physics studies dealing with the numerical modeling of the response of protective structures under the synergistic effect of a blast wave and the impact of fragments, are quite limited in the literature. This article numerically evaluates the nonlinear dynamic behavior and damage mechanisms of Aluminum plates EN AW-1050A- H24 under different combined loading scenarios varied by the sequence of the applied loads using the commercial software LS-DYNA. For one hand, with respect to the terminal ballistic field investigations, a Lagrangian (LAG) formulation is used to evaluate the different failure modes of the target material in case of a fragment impact. On the other hand, with respect to the blast field analysis, an Arbitrary Lagrangian-Eulerian (ALE) formulation is considered to study the fluid-structure interaction (FSI) of the shock wave and the plate in case of a blast loading. Four different loading scenarios are considered: (1) only blast loading, (2) only fragment impact, (3) blast loading followed by a fragment impact and (4) a fragment impact followed by blast loading. From the numerical results, it was observed that when the impact load is applied to the plate prior to the blast load, it suffers more severe damage due to the hole enlargement phenomenon and the effects of crack propagation on the circumference of the damaged zone. Moreover, it was found that the hole from the fragment impact loading was enlarged to about three times in diameter as compared to the diameter of the projectile. The validation of the proposed computational model is based in part on previous experimental data obtained by the authors and in the other part on experimental data obtained from the literature. A good correspondence between the numerical and experimental results is found.

Keywords: computational analysis, combined loading, explosion mechanics, hole enlargement phenomenon, impact physics, synergistic effect, terminal ballistic

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4014 PSS and SVC Controller Design by BFA to Enhance the Power System Stability

Authors: Saeid Jalilzadeh

Abstract:

Designing of PSS and SVC controller based on Bacterial Foraging Algorithm (BFA) to improve the stability of power system is proposed in this paper. Same controllers for PSS and SVC has been considered and Single machine infinite bus (SMIB) system with SVC located at the terminal of generator is used to evaluate the proposed controllers. BFA is used to optimize the coefficients of the controllers. Finally simulation for a special disturbance as an input power of generator with the proposed controllers in order to investigate the dynamic behavior of generator is done. The simulation results demonstrate that the system composed with optimized controllers has an outstanding operation in fast damping of oscillations of power system.

Keywords: PSS, SVC, SMIB, optimize controller

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4013 SUSTAINEXT–Validating a Zero-Waste: Dynamic, Multivalorization Route Biorefinery for Plant Extracts

Authors: Adriana Diaz Triana, Wolfgang Wimmer, Sebastian Glaser, Rainer Pamminger

Abstract:

SUSTAINEXT is a pioneer initiative in Extremadura, Spain under the EU Biobased industries. SUSTANEXT will scale-up and validate an industrial facility to produce botanical extracts, based on three key pillars. First, the whole valorization of bio-based feedstocks with a zero-waste and zero-emissions ambition. SUSTAINEXT will be deployed with six feedstocks. Three medicinal and aromatic plants (Rosemary, Chamomile, and Lemon verbena) will be locally sourced from disused tobacco fields with installed agri-voltaics; and three underexploited agro-industrial side streams will be further valorized (Olive, artichoke-cardoon, and pomegranate). Second, a dynamic, analytical biorefinery (DYANA) will isolate polyphenol and tri-terpenes from feedstocks in a disruptive and circular way. SUSTAINEXT explores 12 valorization routes (VRs) to extract and purify 46 functional ingredients, of which 13 are new in the market and 12 are newly produced in Europe. Third, the integrated and versatile value chain engages all actors, from feedstocks suppliers to extract users in the industries of food, animal feed, nutraceuticals, cosmetics, chemical performance, soil enhancers and fertilizers. This paper addresses SUTAINEXT activities towards zero impacts and full regulatory compliance. A comprehensive Life Cycle Thinking approach is proposed, with four complementary assessments running iteratively along the project duration (4,5 years). These are the Life Cycle Cost (LCCA), Life Cycle (LCA), Social Life Cycle (S-LCA) and Circularity (CA) assessments. The LCA will help evaluate the feedstock suitability parameters and intrinsic characteristics that quantify the feedstock´s grade for a determined use, and the feedstock´s suitability index for a specific VR. The LCA will also study the emissions, land use change, energy generation and consumption, and other environmental aspects and impacts of the VRs, to identify the most resource efficient and less impactful distribution of products from the circular biorefinery model used in SUSTAINEXT. Challenges to complete the LCA include the definition of the system boundaries, carrying out a robust inventory, and the proper allocation of impacts to the different VRs.

Keywords: biorefinery, botanical extracts, life cycle assessment, valorization routes.

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4012 Governance Structure of Islamic Philanthropic Institution: Analysis of Corporate WAQF in Malaysia

Authors: Nathasa Mazna Ramli, Nurul Husna Mohd Salleh, Nurul Aini Muhamed

Abstract:

This study focuses on the governance of an Islamic philanthropic institution in Malaysia. Specifically, the internal governance structure of corporate Islamic endowment, or waqf, is being analysed. The purposes of waqf are to provide continuous charity that could generate perpetual income flow for the needy. This study is based on the principle of MCCG 2012, Shariah Governance Framework and charity governance. This study utilises publicly available data to examine the internal governance structure of a corporate waqf. This study finds that the Islamic philanthropic Institution practices, to some extent, have a sound governance structure to discharge their transparency and accountability. Furthermore, findings also showed that though governance structure is in place, most of the structures are not disclosed in the annual reports of the company. Findings from the study could extend the knowledge in these areas and stimulate further research on the governance of Islamic philanthropic institutions, particularly for corporate waqf.

Keywords: accountability, governance, Islamic philanthropic, corporate waqf

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4011 A Case Study of Meningoencephalitis following Le Fort I Osteotomy

Authors: Ryan Goh, Nicholas Beech

Abstract:

Introduction: Le Fort I Osteotomies, although are common procedures in Oral and Maxillofacial Surgery, carry a degree of risk of unfavourable propagation of the down-fracture of the maxilla. This may be the first reported case in the literature for meningoencephalitis to occur following a Le Fort I Osteotomy. Case: A 32-year-old female was brought into the Emergency Department four days after a Le Fort I Osteotomy, with a Glasgow Coma Scale (GCS) of 8 (E3V1M4). A Computed Tomography (CT) Head showed a skull base fracture at the right sphenoid sinus. Lumbar puncture was completed, and Klebsiella oxytoca was found in the Cerebrospinal Fluid (CSF). She was treated with Meropenem, and rapidly improved thereafter. CSF rhinorrhoea was identified when she was extubated, which was successfully managed via a continuous lumbar drain. She was discharged on day 14 without any neurological deficits. Conclusion: The most likely aspect of the Le Fort I Osteotomy to obtain a skull base fracture is during the pterygomaxillary disjunction. Care should always be taken to avoid significant risks of skull base fractures, CSF rhinorrhoea, meningitis and encephalitis.

Keywords: meningitis, orthognathic surgery, post-operative complication, skull base, rhinorrhea

Procedia PDF Downloads 125