Search results for: code blue simulation module

Authors: M. R. Akbari , H. Yousefnia, E. Mirrezaei

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Range uncertainties of protons are currently a topic of interest in proton therapy. Two of the parameters that are often used to specify proton range are water equivalent thickness (WET) and water equivalent ratio (WER). Since WER values for a specific material is nearly constant at different proton energies, it is a more useful parameter to compare. In this study, WER values were calculated for different proton energies in polymethyl methacrylate (PMMA), polystyrene (PS) and aluminum (Al) using FLUKA and TRIM codes. The results were compared with analytical, experimental and simulated SEICS code data obtained from the literature. In FLUKA simulation, a cylindrical phantom, 1000 mm in height and 300 mm in diameter, filled with the studied materials was simulated. A typical mono-energetic proton pencil beam in a wide range of incident energies usually applied in proton therapy (50 MeV to 225 MeV) impinges normally on the phantom. In order to obtain the WER values for the considered materials, cylindrical detectors, 1 mm in height and 20 mm in diameter, were also simulated along the beam trajectory in the phantom. In TRIM calculations, type of projectile, energy and angle of incidence, type of target material and thickness should be defined. The mode of 'detailed calculation with full damage cascades' was selected for proton transport in the target material. The biggest difference in WER values between the codes was 3.19%, 1.9% and 0.67% for Al, PMMA and PS, respectively. In Al and PMMA, the biggest difference between each code and experimental data was 1.08%, 1.26%, 2.55%, 0.94%, 0.77% and 0.95% for SEICS, FLUKA and SRIM, respectively. FLUKA and SEICS had the greatest agreement (≤0.77% difference in PMMA and ≤1.08% difference in Al, respectively) with the available experimental data in this study. It is concluded that, FLUKA and TRIM codes have capability for Bragg curves simulation and WER values calculation in the studied materials. They can also predict Bragg peak location and range of proton beams with acceptable accuracy.

Keywords: water equivalent ratio, dosimetric materials, proton therapy, Monte Carlo simulations

Procedia PDF Downloads 326

Authors: Kamila Mazur-Oleszczuk, Rafal Banasiuk, Dawid Krasnowski, Maciej Pek, Marcin Podgorski, Krzysztof Rykaczewski, Sabina Zoledowska, Dawid Nidzworski

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Workout safety is one of the most significant challenges of recreational sports. Loss of water and electrolytes is a consequence of thermoregulatory sweating during exercise. The rate of sweat loss and its chemical composition can fluctuate within and among individuals. That is why we propose our sportband 'Flow' as a device for monitoring these parameters. 'Flow' consists of two parts: an intelligent module and a mobile application. The application allows verifying the training progress and data archiving. The sportband intelligent module includes temperature, heart rate and pulse measurement (non-invasive, continuous methods of workout monitoring). Apart from the standard components, the device will consist of a sweat composition analyzer situated in sportband intelligent module. Sweat is a water solution of numerous compounds such as ions (sodium up to 1609 µg/ml, potassium up to 274 µg/ml), lactic acid (skin pH is between 4.5 - 6) and a small amount of glucose. Awareness of sweat composition allows personalizing electrolyte intake after training. A comprehensive workout monitoring (sweat composition, heart rate, blood oxygen level) will provide improvement in the training routine and time management, which is our goal for the development of the sweat composition analyzer.

Keywords: flow, sportband, sweat, workout monitoring

Procedia PDF Downloads 153

Authors: Jiří Barta

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The paper deals with simulation programs of spread of harmful substances. Air pollution has a direct impact on the quality of human life and environmental protection is currently a very hot topic. Therefore, the paper focuses on the simulation of release of harmful substances. The first part of article deals with perspectives and possibilities of implementation outputs of simulations programs into the system which is education and of practical training of the management staff during emergency events in the frame of critical infrastructure. The last part shows the practical testing and evaluation of simulation programs. Of the tested simulations software been selected Symos97. The tool offers advanced features for setting leakage. Gradually allows the user to model the terrain, location, and method of escape of harmful substances.

Keywords: Computer Simulation, Symos97, Spread, Simulation Software, Harmful Substances

Procedia PDF Downloads 299

Authors: Tzen-Ying Ling

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Recently, the resilience of dwellings in urban areas has been deliberated, as to accommodate the growing demand for changing the demography and rapid urbanization. The need to incorporate sustainability and cleaner production thinking have intensified to mitigate climate risks and satisfy the demand for housing. The modular thinking satisfies both the pressing call for fast-tracked housing stocks; while meeting the goal of more sustainable production. In the other side, the importance of the dwelling as a podium for well-being and social connectedness are sought to explore the key human/environment design thinking for the modular system in dwelling. We argue the best practice incorporates the concept of systemic components thinking. The fieldwork reported in this paper illustrates the process of the case study in a modular dwelling unit prototype development; focusing on the systemic frame system design process and adjustment recommendation hereafter. Using a case study method, the study identified that: (1) inclusive human dimensional factoring through systemic design thinking results in affordable implementations possibilities. (2) The environmental dimension encourages the place-based solution suited for the locality and the increasing demand for dwelling in the urban system. (3) Prototype design consideration avails module system component as dwelling construction alternative. (4) Building code often acts as an inhibitor for such dwelling units by the restriction in lot sizes and units placement. The demand for fast-track dwelling construction and cleaner production decisively outweighs the code inhibition; we further underscored the sustainability implication of the alternative prototype as the core of this study. The research suggests that modular thinking results in a resilient solution suited for the locality and the increasing demand for dwelling in the urban system.

Keywords: system prototype, urban resilience, human/environment dimension, modular thinking, dwelling alternative

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Authors: Hang Yang, Jichao Li, Kewei Yang, Tianyang Lei

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Multivariate time series anomaly detection is a significant research topic in the field of data mining, encompassing a wide range of applications across various industrial sectors such as traffic roads, financial logistics, and corporate production. The inherent spatial dependencies and temporal characteristics present in multivariate time series introduce challenges to the anomaly detection task. Previous studies have typically been based on the assumption that all variables belong to the same spatial hierarchy, neglecting the multi-level spatial relationships. To address this challenge, this paper proposes a multi-scale spatial and unified temporal feature fusion network, denoted as MSUT-Net, for multivariate time series anomaly detection. The proposed model employs a multi-level modeling approach, incorporating both temporal and spatial modules. The spatial module is designed to capture the spatial characteristics of multivariate time series data, utilizing an adaptive graph structure learning model to identify the multi-level spatial relationships between data variables and their attributes. The temporal module consists of a unified temporal processing module, which is tasked with capturing the temporal features of multivariate time series. This module is capable of simultaneously identifying temporal dependencies among different variables. Extensive testing on multiple publicly available datasets confirms that MSUT-Net achieves superior performance on the majority of datasets. Our method is able to model and accurately detect systems data with multi-level spatial relationships from a spatial-temporal perspective, providing a novel perspective for anomaly detection analysis.

Keywords: data mining, industrial system, multivariate time series, anomaly detection

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Authors: Lixin Tian, Wei Xue

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Many jobs in society go underground, such as mine mining, tunnel construction and subways, which are vital to the development of society. Once accidents occur in these places, the interruption of traditional wired communication is not conducive to the development of rescue work. In order to realize the positioning, early warning and command functions of underground personnel and improve rescue efficiency, it is necessary to develop and design an emergency ground communication system. It is easy to be subjected to narrowband interference when performing conventional underground communication. Spreading communication can be used for this problem. However, general spread spectrum methods such as direct spread communication are inefficient, so it is proposed to use parallel combined spread spectrum (PCSS) communication to improve efficiency. The PCSS communication not only has the anti-interference ability and the good concealment of the traditional spread spectrum system, but also has a relatively high frequency band utilization rate and a strong information transmission capability. So, this technology has been widely used in practice. This paper presents a PCSS communication model-multiple detection parallel combined spread spectrum (MDPCSS) communication system. In this paper, the principle of MDPCSS communication system is described, that is, the sequence at the transmitting end is processed in blocks and cyclically shifted to facilitate multiple detection at the receiving end. The block diagrams of the transmitter and receiver of the MDPCSS communication system are introduced. At the same time, the calculation formula of the system bit error rate (BER) is introduced, and the simulation and analysis of the BER of the system are completed. By comparing with the common parallel PCSS communication, we can draw a conclusion that it is indeed possible to reduce the BER and improve the system performance. Furthermore, the influence of different pseudo-code lengths selected on the system BER is simulated and analyzed, and the conclusion is that the larger the pseudo-code length is, the smaller the system error rate is.

Keywords: cyclic shift, multiple detection, parallel combined spread spectrum, PN code

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Authors: Ziba Khalili, Mohsen Sheikholeslami, Ladan Momayez

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Combining the photovoltaic/thermal (PVT) systems with a thermoelectric (TE) module can raise energy yields since the TE module boosts the system's energy conversion efficiency. In the current study, a PVT system integrated with a TE module was designed and simulated in ANSYS Fluent 19.2. A copper heat transfer tube (HTT) was employed for cooling the photovoltaic (PV) cells. Four different shapes of HTT cross-section, i.e., circular, square, elliptical, and triangular, with equal cross-section areas were investigated. Also, the influence of Cu-Al2O3/water hybrid nanofluid (0.024% volume concentration), fluid inlet velocity (uᵢ ), and amount of solar radiation (G), on the PV temperature (Tₚᵥ) and system performance were investigated. The ambient temperature (Tₐ), wind speed (u𝓌), and fluid inlet temperature (Tᵢ), were considered to be 25°C, 1 m/s, and 27°C, respectively. According to the obtained data, the triangular case had the greatest impact on reducing the compared to other cases. In the triangular case, examination of the effect of hybrid nanofluid showed that the use of hybrid nanofluid at 800 W/m2 led to a reduction of the TPV by 0.6% compared to water, at 0.19 m/s. Moreover, the thermal efficiency ( ) and the overall electrical efficiency (nₜ) of the system improved by 0.93% and 0.22%, respectively, at 0.19 m/s. In a triangular case where G and were 800 W/m2 and 19 m/s, respectively, the highest amount of, thermal power (Eₜ), and, were obtained as 72.76%, 130.84 W and 12.03%, respectively.

Keywords: electrical performance, photovoltaic/thermal, thermoelectric, hybrid nanofluid, thermal efficiency

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Authors: Yang Xiaodong

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This article explores the application and structural characteristics of flexible and programmable systems in electronic systems, with a focus on analyzing their advantages and architectural differences in dealing with complex environments. By introducing mathematical models and simulation experiments, the performance of dynamic module combination in flexible systems and fixed path selection in programmable systems in resource utilization and performance optimization was demonstrated. This article also discusses the mutual transformation between the two in practical applications and proposes a solution to improve system flexibility and performance through dynamic reconfiguration technology. This study provides theoretical reference for the design and optimization of flexible and programmable systems.

Keywords: flexibility, programmable, electronic systems, system architecture

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Authors: Jaimala Ghambir, Tilak Thakur, Puneet Chawla

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As per the statistical data, the Doubly-fed Induction Generator (DFIG) based wind turbine with variable speed and variable pitch control is the most common wind turbine in the growing wind market. This machine is usually used on the grid connected wind energy conversion system to satisfy grid code requirements such as grid stability, fault ride through (FRT), power quality improvement, grid synchronization and power control etc. Though the requirements are not fulfilled directly by the machine, the control strategy is used in both the stator as well as rotor side along with power electronic converters to fulfil the requirements stated above. To satisfy the grid code requirements of wind turbine, usually grid side converter is playing a major role. So in order to improve the operation capacity of wind turbine under critical situation, the intensive study of both machine side converter control and grid side converter control is necessary In this paper DFIG is modeled using power components as variables and the performance of the DFIG system is analysed under grid voltage fluctuations. The voltage fluctuations are made by lowering and raising the voltage values in the utility grid intentionally for the purpose of simulation keeping in view of different grid disturbances.

Keywords: DFIG, dynamic modeling, DPC, sag, swell, voltage fluctuations, FRT

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Authors: Hussein Yousif Aziz

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This paper discussed the design and analysis of bridge foundation subjected to load of train with three codes, namely AASHTO code, British Standard BS Code 8004 (1986), and Chinese code (TB10002.5-2005).The study focused on the design and analysis of bridge’s foundation manually with the three codes and found which code is better for design and controls the problem of high settlement due to the applied loads. The results showed the Chinese codes are costly that the number of reinforcement bars in the pile cap and piles is more than those with AASHTO code and BS code with the same dimensions. Settlement of the bridge was calculated depending on the data collected from the project site. The vertical ultimate bearing capacity of single pile for three codes is also discussed. Other analyses by using the two-dimensional Plaxis program and other programs like SAP2000 14, PROKON many parameters are calculated. The maximum values of the vertical displacement are close to the calculated ones. The results indicate that the AASHTO code is economics and safer in the bearing capacity of single pile. The purpose of this project is to study out the pier on the basis of the design of the pile foundation. There is a 32m simply supported beam of box section on top of the structure. The pier of bridge is round-type. The main component of the design is to calculate pile foundation and the settlement. According to the related data, we choose 1.0m in diameter bored pile of 48m. The pile is laid out in the rectangular pile cap. The dimension of the cap is 12m 9 m. Because of the interaction factors of pile groups, the load-bearing capacity of simple pile must be checked, the punching resistance of pile cap, the shearing strength of pile cap, and the part in bending of pile cap, all of them are very important to the structure stability. Also, checking soft sub-bearing capacity is necessary under the pile foundation. This project provides a deeper analysis and comparison about pile foundation design schemes. Firstly, here are brief instructions of the construction situation about the Bridge. With the actual construction geological features and the upper load on the Bridge, this paper analyzes the bearing capacity and settlement of single pile. In the paper the Equivalent Pier Method is used to calculate and analyze settlements of the piles.

Keywords: pile foundation, settlement, bearing capacity, civil engineering

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Authors: Amir Reza Radmanesh, Sina Farajzadeh Khosroshahi, Hani Sadr

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The transient catalytic converter performance is governed by complex interactions between exhaust gas flow and the monolithic structure of the catalytic converter. Stringent emission regulations around the world necessitate the use of highly-efficient catalytic converters in vehicle exhaust systems. Computational fluid dynamics (CFD) is a powerful tool for calculating the flow field inside the catalytic converter. Radial velocity profiles, obtained by a commercial CFD code, present very good agreement with respective experimental results published in the literature. However the applicability of CFD for transient simulations is limited by the high CPU demands. In the present work, Geometric modeling ceramic monolith substrate is done with square shaped channel type of Catalytic converter and it is coated platinum and palladium. This example illustrates the effect of flow distribution on thermal response of a catalytic converter and different gas flow velocities, during the critical phase of catalytic converter warm up.

Keywords: catalytic converter, computational fluid dynamic, porous media, velocity distribution

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Authors: Hayle Makda Gebru

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Companies are inevitable for society. They are the building blocks of every development in a country aimed at producing continuous goods and services for the people and, in turn, obliged to pay taxes, which enhances the economy of the nation. For the proper functioning of companies, their relationship with their stakeholders must be secure. The major stakeholders are suppliers, consumers, employees, creditors, etc. The law plays an important role in enhancing the relationship between these different stakeholders. If the law fails to keep track of the relationship, both the company and stakeholders remain unprotected. As a result, the potential benefits are prejudiced. This paper makes a comparative analysis of the types and formation of companies under the Transitional Commercial Code of Eritrea and the Company Law of the Peoples Republic of China. In particular, the paper addresses the legal lacuna under the TCrCE on handling the failure of shareholders to pay the promised capital. So, the methodology of the study is entirely analyzing the two countries' laws using practical cases. After analyzing the practical problems on the ground using real cases, this paper calls on Eritrea to update its outdated Commercial Code to give proper protection to the stakeholders.

Keywords: companies, company law of the People's Republic of China, transitional commercial code of Eritrea, protection of stakeholders, failure to pay the promised capital

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Authors: Indranil Chakraborty, Kalyan Mandal

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Herein, we synthesize MnFe₂O₄ nano−hollow spheres (NHSs) of average diameter 100 nm through a facile template free solvothermal process and carry out a time dependent morphological study to investigate their process of core excavation. Further, a surface engineering of as−synthesized MnFe₂O₄ NHSs has been executed with organic disodium tartrate dihydrate ligand and interestingly, the surface modified MnFe₂O₄ NHSs are found to capable of emerging multicolor fluorescence starting from blue, green to red. The magnetic measurements through vibrating sample magnetometer demonstrate that room temperature superparamagnetic nature of MnFe₂O₄ NHSs remains unaltered after surface modification. Moreover, functionalized MnFe₂O₄ NHSs are found to exhibit excellent reusable photocatalytic efficiency in the degradation of cationic dye, methylene blue with rate constant of 2.64×10−2 min.

Keywords: nano hollow sphere, tartrate modification, multiple fluorescence, catalytic property

Procedia PDF Downloads 187

Authors: Haroon Abdelrahman Mohamed Saeed, Hongjun Yang

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This study aims to examine the impact of hyperbranched polyester (AA-Ph) on the dyeability and color fastness of recycled poly (ethylene terephthalate) (RPET) fabric. AA-Ph was synthesized through single-step melt polycondensation of adipic acid (AA) and phloroglucinol (Ph) and then incorporated into RPET before spinning. The addition of AA-Ph significantly improves the dye uptake of recycled PET when dyed with disperse dye blue 56 due to the introduction of polar groups and aromatic rings. The blends RPET-3 and RPET-5 show strong abrasion resistance, dyeability, and washing fastness. Furthermore, these blends exhibit high moisture absorbance owing to the polar groups and aromatic structures, as demonstrated by exhaustion tests, which enhance perspiration absorption for added comfort in apparel. Overall, RPET-3 and RPET-5 blends are well-suited for various textile applications, especially in garment manufacturing.

Keywords: recycled poly (ethylene terephthalate), hyperbranched polyester, dyeability, dye blue

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Authors: Zahra Tolou-Ghamari

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Objective: Health care associated with multiresistant pathogens is rising globally. It is well known that nosocomial infections increase hospital stay, morbidity, mortality, and disability. Therefore, the aim of this study was to define the occurrence of nosocomial infections in a tertiary hospital in Isfahan/Iran. Materials and Methods: The data were extracted from the official database of hospital nosocomial infections records that included 9152 vertical rows. For each patient, the reported infections were coded by number as UTI-SUTI; Code 55, VAE-PVAP; Code 56, BSI-LCBI Code 19, SSI-DIP; Code 14, and so on. For continuous variables, mean ± standard deviation and for categorical variables, the frequency was used. Results: The study population was 5542 patients, comprised of males (n=3282) and females (n=2260). With a minimum of 15 and a maximum of 99, the mean age in 5313 patients was 58.5 ± 19.1 years old. The highest reported nosocomial infections (n= 77%) were associated with the ages 30-80 years old. Sites of nosocomial infections in 87% were as: VAE-PVAP; 27.3%, VAE-IVAC; 7.7, UTI-SUTI; 29.5%, BSI-LCBI; 12.9%, SSI-DIP; 9.5% and other individual infection (13%) with the main pathogens klebsiella pneumonia, acinetobacter baumannii and staphylococcus. Conclusions: For an efficient surveillance system, adopting pharmacotherapy used antibiotics in terms of monotherapy or polypharmacy control policy, in addition to advanced infection control programs at regional and national levels in Iran recommended.

Keywords: infection, nosocomial, ventilator, blood stream, Isfahan, Iran

Procedia PDF Downloads 79

Authors: S. Thomet, S. De-Paoli, F. Ghaffari, J. M. Daveau, P. Roche, O. Romain

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In this paper, we present a hardware module dedicated to understanding the fail reason of a System on Chip (SoC) exposed to a particle beam. Impact of Single-Event Effects (SEE) on processor-based SoCs is a concern that has increased in the past decade, particularly for terrestrial applications with automotive safety increasing requirements, as well as consumer and industrial domains. The SEE created by the impact of a particle on an SoC may have consequences that can end to instability or crashes. Specific hardening techniques for hardware and software have been developed to make such systems more reliable. SoC is then qualified using cosmic ray Accelerated Soft-Error Rate (ASER) to ensure the Soft-Error Rate (SER) remains in mission profiles. Understanding where errors are occurring is another challenge because of the complexity of operations performed in an SoC. Common techniques to monitor an SoC running under a beam are based on non-intrusive debug, consisting of recording the program counter and doing some consistency checking on the fly. To detect and understand SEE, we have developed a module embedded within the SoC that provide support for recording probes, hardware watchpoints, and a memory mapped register bank dedicated to software usage. To identify CPU failure modes and the most important resources to probe, we have carried out a fault injection campaign on the RTL model of the SoC. Probes are placed on generic CPU registers and bus accesses. They highlight the propagation of errors and allow identifying the failure modes. Typical resulting errors are bit-flips in resources creating bad addresses, illegal instructions, longer than expected loops, or incorrect bus accesses. Although our module is processor agnostic, it has been interfaced to a RISC-V by probing some of the processor registers. Probes are then recorded in a ring buffer. Associated hardware watchpoints are allowing to do some control, such as start or stop event recording or halt the processor. Finally, the module is also providing a bank of registers where the firmware running on the SoC can log information. Typical usage is for operating system context switch recording. The module is connected to a dedicated debug bus and is interfaced to a remote controller via a debugger link. Thus, a remote controller can interact with the monitoring module without any intrusiveness on the SoC. Moreover, in case of CPU unresponsiveness, or system-bus stall, the recorded information can still be recovered, providing the fail reason. A preliminary version of the module has been integrated into a test chip currently being manufactured at ST in 28-nm FDSOI technology. The module has been triplicated to provide reliable information on the SoC behavior. As the primary application domain is automotive and safety, the efficiency of the module will be evaluated by exposing the test chip under a fast-neutron beam by the end of the year. In the meantime, it will be tested with alpha particles and electromagnetic fault injection (EMFI). We will report in the paper on fault-injection results as well as irradiation results.

Keywords: fault injection, SoC fail reason, SoC soft error rate, terrestrial application

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Authors: Mohamed Ramdani, Hassen Abdellaoui, Abdenour Boudrassen

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Mobile platform’s attitude estimation approaches mainly based on combined positioning techniques and developed algorithms; which aim to reach a fast and accurate solution. In this work, we describe the design and the implementation of an attitude determination (AD) process, using only measurements from GPS sensors. The major issue is based on smoothed GPS code data using Hatch filter and raw carrier-phase measurements integrated into attitude algorithm based on vectors measurement using least squares (LSQ) estimation method. GPS dataset from a static experiment is used to investigate the effectiveness of the presented approach and consequently to check the accuracy of the attitude estimation algorithm. Attitude results from GPS multi-antenna over short baselines are introduced and analyzed. The 3D accuracy of estimated attitude parameters using smoothed measurements is over 0.27°.

Keywords: attitude determination, GPS code data smoothing, hatch filter, carrier-phase measurements, least-squares attitude estimation

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Authors: Cosmas Maphosa, Ndileleni P. Mudzielwana, Lufuno Netshifhefhe

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Core business in a university centers on a curriculum. Teaching, learning, assessment and university products all have a bearing on the curriculum. In this discussion paper, the researchers engage in theoretical underpinnings of curriculum development in universities in South Africa. The paper is hinged on the realization that meaningful curriculum development is only possible if academic staff member has a thorough understanding of curriculum, curriculum design principles, and processes. Such understanding should be informed by theory. In this paper, the researchers consider curriculum, curriculum orientations, and the role of learning outcomes in curriculum development. Important and key considerations in module/course design are discussed and relevant examples given. The issue of alignment, as an important aspect of module/course design, is also explained and exemplified. Conclusions and recommendations are made.

Keywords: curriculum, curriculum development, knowledge, graduate attributes, competencies, teaching and learning

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Authors: Kai Jin, Hua Li, Qing Song

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Homeland security and border safety is an issue for any country. This paper takes the border security of US as an example to discuss the usage and efficiency of simulation tools in the homeland security application. In this study, available resources and different illegal infiltration parameters are defined, including their individual behavior and objective, in order to develop a model that describes border patrol system. A simulation model is created in Arena. This simulation model is used to study the dynamic activities in the border security. Possible factors that may affect the effectiveness of the border patrol system are proposed. Individual and factorial analysis of these factors is conducted and some suggestions are made.

Keywords: resource optimization, simulation, modeling, border security

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Authors: D. Ramajo, S. Corzo, M. Nigro

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A Multi-dimensional computational fluid dynamics (CFD) two-phase model was developed with the aim to simulate the in-core coolant circuit of a pressurized heavy water reactor (PHWR) of a commercial nuclear power plant (NPP). Due to the fact that this PHWR is a Reactor Pressure Vessel type (RPV), three-dimensional (3D) detailed modelling of the large reservoirs of the RPV (the upper and lower plenums and the downcomer) were coupled with an in-house finite volume one-dimensional (1D) code in order to model the 451 coolant channels housing the nuclear fuel. Regarding the 1D code, suitable empirical correlations for taking into account the in-channel distributed (friction losses) and concentrated (spacer grids, inlet and outlet throttles) pressure losses were used. A local power distribution at each one of the coolant channels was also taken into account. The heat transfer between the coolant and the surrounding moderator was accurately calculated using a two-dimensional theoretical model. The implementation of subcooled boiling and condensation models in the 1D code along with the use of functions for representing the thermal and dynamic properties of the coolant and moderator (heavy water) allow to have estimations of the in-core steam generation under nominal flow conditions for a generic fission power distribution. The in-core mass flow distribution results for steady state nominal conditions are in agreement with the expected from design, thus getting a first assessment of the coupled 1/3D model. Results for nominal condition were compared with those obtained with a previous 1/3D single-phase model getting more realistic temperature patterns, also allowing visualize low values of void fraction inside the upper plenum. It must be mentioned that the current results were obtained by imposing prescribed fission power functions from literature. Therefore, results are showed with the aim of point out the potentiality of the developed model.

Keywords: PHWR, CFD, thermo-hydraulic, two-phase flow

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Authors: Young S. Bang, Dong H. Yoon, Seung H. Yoo

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Emergency Core Coolant Bypass (ECC Bypass) has been regarded as an important phenomenon to peak cladding temperature of large-break loss-of-coolant-accidents (LBLOCA) in nuclear power plants (NPP). A modeling scheme to address the ECC Bypass phenomena and the calculation of LBLOCA using that scheme are discussed in the present paper. A hydraulic form loss coefficient (HFLC) from the reactor vessel downcomer to the broken cold leg is predicted by the computational fluid dynamics (CFD) code with a variation of the void fraction incoming from the downcomer. The maximum, mean, and minimum values of FLC are derived from the CFD results and are incorporated into the LBLOCA calculation using a system thermal-hydraulic code, MARS-KS. As a relevant parameter addressing the ECC Bypass phenomena, the FLC to the break and its range are proposed.

Keywords: CFD analysis, ECC bypass, hydraulic form loss coefficient, system thermal-hydraulic code

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Authors: Mucahit Unal, Ibrahim Arslan

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The New Turkish Commercial Code (TCC) No. 6102 was published in the Official Gazette on February 14, 2011. As stated in the New Turkish Commercial Code No. 6102 and Law No. 6103 on Validity and Application of the Turkish Commercial Code, TCC came into effect on July 1, 2012. The basic purpose of the TCC is to form corporate governance coherent with the international standards; to provide transparency in company management; to adjust the Turkish Commercial Code rules with European Union legislations and to simplify establishing a company for foreigner investors to move investments to Turkish market. In this context according to TCC, joint stock companies and limited liability companies can establish with only one single shareholder; the one single shareholder can be foreigner; all board of director members can be foreigner, also all shareholders and board of director members can be non-resident foreigners. Additionally, TCC does not require physical participation to the general shareholders and board members meetings. TCC allows that the general shareholders and board members meetings can hold in an electronic form and resolution of these meetings may also be approved via electronic signatures. Through this amendment, foreign investors no longer have to deal with red tapes. This amendment also means the TCC prevents foreign companies from incurring unnecessary travel expenses. In accordance with all this amendments about TCC, to invest in Turkish market is easy, simple and transparent for foreigner investors and also investors can establish a company in Turkey, irrespective of nationality or place of residence. This article aims to analyze ‘Establish a Company in Turkey for Foreigners’ and inform investors about investing (especially establishing a company) in the Turkish market.

Keywords: establish a company, foreigner investors, invest in Turkish market, Turkish commercial code

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Authors: Jerzy Merkisz, Pawel Fuc, Piotr Lijewski, Andrzej Ziolkowski, Pawel Czarkowski

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The paper presents preliminary results of the development of an automotive exhaust gas energy recovery module. The aim of the performed analyses was to select the geometry of the heat exchanger that would ensure the highest possible transfer of heat at minimum heat flow losses. The starting point for the analyses was a straight portion of a pipe, from which the exhaust system of the tested vehicle was made. The design of the heat exchanger had a cylindrical cross-section, was 300 mm long and was fitted with a diffuser and a confusor. The model works were performed for the mentioned geometry utilizing the finite volume method based on the Ansys CFX v12.1 and v14 software. This method consisted in dividing of the system into small control volumes for which the exhaust gas velocity and pressure calculations were performed using the Navier-Stockes equations. The heat exchange in the system was modeled based on the enthalpy balance. The temperature growth resulting from the acting viscosity was not taken into account. The heat transfer on the fluid/solid boundary in the wall layer with the turbulent flow was done based on an arbitrarily adopted dimensionless temperature. The boundary conditions adopted in the analyses included the convective condition of heat transfer on the outer surface of the heat exchanger and the mass flow and temperature of the exhaust gas at the inlet. The mass flow and temperature of the exhaust gas were assumed based on the measurements performed in actual traffic using portable PEMS analyzers. The research object was a passenger vehicle fitted with a 1.9 dm3 85 kW diesel engine. The tests were performed in city traffic conditions.

Keywords: waste heat recovery, heat exchanger, CFD simulation, pems

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Authors: Edward Guillén, Jhordany Rodriguez, Rafael Páez

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Anomaly detection techniques have been focused on two main components: data extraction and selection and the second one is the analysis performed over the obtained data. The goal of this paper is to analyze the influence that each of these components has over the system performance by evaluating detection over network scenarios with different setups. The independent variables are as follows: the number of system inputs, the way the inputs are codified and the complexity of the analysis techniques. For the analysis, some approaches of artificial neural networks are implemented with different number of layers. The obtained results show the influence that each of these variables has in the system performance.

Keywords: network intrusion detection, machine learning, artificial neural network, anomaly detection module

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Authors: Fadila Hadjeris

Abstract:

The study aims at investigating the functions of English-Arabic code switching in English as a foreign language classroom oral discourse and the extent to which they can contribute to the flow of classroom interaction. It also seeks to understand the views, beliefs, and perceptions of teachers and learners towards this practice. We hypothesized that code switching is a communicative strategy which facilitates classroom interaction. Due to this fact, both teachers and learners support its use. The study draws on a key body of literature in bilingualism, second language acquisition, and classroom discourse in an attempt to provide a framework for considering the research questions. It employs a combination of qualitative and quantitative research methods which include classroom observations and questionnaires. The analysis of the recordings shows that teachers’ code switching to Arabic is not only used for academic and classroom management reasons. Rather, the data display instances in which code switching is used for social reasons. The analysis of the questionnaires indicates that teachers and pupils have different attitudes towards this phenomenon. Teachers reported their deliberate switching during EFL teaching, yet the majority was against this practice. According to them, the use of the mother has detrimental effects on the acquisition and the practice of the target language. In contrast, pupils showed their preference to their teachers’ code switching because it enhances and facilitates their understanding. These findings support the fact that the shift to pupils’ mother tongue is a strategy which aids and facilitates the teaching and the learning of the target language. This, in turn, necessitates recommendations which are suggested to teachers and course designers.

Keywords: bilingualism, codeswitching, classroom interaction, classroom discourse, EFL learning/ teaching, SLA

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Authors: Zhuohan Li, Jing Yang, Yaoyuan Cui

Abstract:

The gut-brain axis (GBA), a communication network between gut microbiota and the brain, benefits for investigation of brain diseases. Currently, organ chips are considered one of the potential tools for GBA research. However, most of the available GBA chips have limitations in replicating the three-dimensional (3D) growth environment of cells and lack the required cell types for barrier function. In the present study, a microfluidic chip was developed for GBA interaction. Blood-brain barrier (BBB) module was prepared with HBMEC, HBVP, U87 cells and decellularized matrix (dECM). Intestinal epithelial barrier (IEB) was prepared with Caco-2 and vascular endothelial cells and dECM. GBA microfluidic device was integrated with IEB and BBB modules using 3D printing interconnecting microchannel scaffolds. BBB and IEB interaction on this GBA chip were evaluated with lipopolysaccharide (LPS) exposure. The present GBA chip achieved multicellular three-dimensional cultivation. Compared with the co-culture cell model in the transwell, fluorescein was absorbed more slowly by 5.16-fold (IEB module) and 4.69-fold (BBB module) on the GBA chip. Accumulation of Rhodamine 123 and Hoechst33342 was dramatically decreased. The efflux function of transporters on IEB and BBB was significantly increased on the GBA chip. After lipopolysaccharide (LPS) disrupted the IEB, and then BBB dysfunction was further observed, which confirmed the interaction between IEB and BBB modules. These results demonstrated that this GBA chip may offer a promising tool for gut-brain interaction study.

Keywords: decellularized matrix, gut-brain axis, organ-on-chip, three-dimensional printing.

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Authors: Morsy Ahmed Morsy Ismail

Abstract:

In this paper, the structure of a coherent homodyne receiver for the Binary Phase Shift Keying (BPSK) Optical Code Division Multiple Access (OCDMA) network is introduced based on the Multi-Length Weighted Modified Prime Code (ML-WMPC) for multimedia applications. The Bit Error Rate (BER) of this homodyne detection is evaluated as a function of the number of active users and the signal to noise ratio for different code lengths according to the multimedia application such as audio, voice, and video. Besides, the Mach-Zehnder interferometer is used as an external phase modulator in homodyne detection. Furthermore, the Multiple Access Interference (MAI) and the receiver noise in a shot-noise limited regime are taken into consideration in the BER calculations.

Keywords: OCDMA networks, bit error rate, multiple access interference, binary phase-shift keying, multimedia

Procedia PDF Downloads 176

Authors: Hoa Pham

Abstract:

Code switching, which can be described as the use of students’ first language in second language classrooms, has long been a controversial topic in the area of language teaching and second language acquisition. While this has been widely investigated across different contexts, little empirical research has been undertaken in Vietnam. The findings of this study contribute to our understanding of bilingual discourse and code switching practices in content and language integrated classrooms, which has significant implications for language teaching and learning in general and in particular for language pedagogy at tertiary level in Vietnam. This study examines the accounts the teachers articulated for their code switching practices in content-based Business English in Vietnam. Data were collected from five teachers through the use of stimulated recall interviews facilitated by the video data to garner the teachers' cognitive reflection, and allowed them to vocalise the motivations behind their code switching behaviour in particular contexts. The literature has recommended that when participants are provided with a large amount of stimuli or cues, they will experience an original situation again in their imagination with great accuracy. This technique can also provide a valuable "insider" perspective on the phenomenon under investigation which complements the researcher’s "outsider" observation. This can create a relaxed atmosphere during the interview process, which in turn promotes the collection of rich and diverse data. Also, participants can be empowered by this technique as they can raise their own concerns and discuss instances which they find important or interesting. The data generated through this study were analysed using a constant comparative approach. The study found that the teachers indicated their support for the use of code switching in their pedagogical practices. Particularly, as a pedagogical resource, the teachers saw code switching to the L1 playing a key role in facilitating the students' comprehension of both content knowledge and the target language. They believed the use of the L1 accommodates the students' current language competence and content knowledge. They also expressed positive opinions about the role that code switching plays in stimulating students' schematic language and content knowledge, encouraging retention and interest in learning and promoting a positive affective environment in the classroom. The teachers perceived that their use of code switching to the L1 helps them meet the students' language needs and prepares them for their study in subsequent courses and addresses functional needs so that students can cope with English language use outside the classroom. Several factors shaped the teachers' perceptions of their code switching practices, including their accumulated teaching experience, their previous experience as language learners, their theoretical understanding of language teaching and learning, and their knowledge of the teaching context. Code switching was a typical phenomenon in the observed classes and was supported by the teachers in certain contexts. This study reinforces the call in the literature to recognise this practice as a useful instructional resource.

Keywords: codeswitching, language teaching, teacher beliefs, tertiary level

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Authors: Ziraguen O. Williams, Shield B. Lin, Fouad N. Matari, Leslie J. Quiocho

Abstract:

In a task to assist NASA in analyzing the dynamic forces caused by operational countermeasures of an astronaut’s exercise platform impacting the spacecraft, feedback delay, and signal noise were added to a simulation model of an active-controlled vibration isolation system to regulate the movement of the exercise platform. Previous simulation work was conducted primarily via MATLAB/Simulink. Two additional simulation tools used in this study were Trick and MBDyn, NASA co-developed software simulation environments. Simulation results obtained from these three tools were very similar. All simulation results support the hypothesis that an active-controlled vibration isolation system outperforms a passive-controlled system even with the addition of feedback delay and signal noise to the active-controlled system. In this paper, squat exercise was used in creating excited force to the simulation model. The exciter force from a squat exercise was calculated from the motion capture of an exerciser. The simulation results demonstrate much greater transmitted force reduction in the active-controlled system than the passive-controlled system.

Keywords: control, counterweight, isolation, vibration

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Authors: Chunye Gong, Ming Tie, Jie Liu, Weimin Bao, Xinbiao Gan, Shengguo Li, Bo Yang, Xuguang Chen, Tiaojie Xiao, Yang Sun

Abstract:

Large-scale CFD simulation relies on high-performance parallel computing, and the load balance is the key role which affects the parallel efficiency. This paper focuses on the load-balancing problem of parallel CFD simulation with structured mesh. A mathematical model for this load-balancing problem is presented. The genetic algorithm, fitness computing, two-level code are designed. Optimal selector, robust operator, and local optimization operator are designed. The properties of the presented genetic algorithm are discussed in-depth. The effects of optimal selector, robust operator, and local optimization operator are proved by experiments. The experimental results of different test sets, DLR-F4, and aircraft design applications show the presented load-balancing algorithm is robust, quickly converged, and is useful in real engineering problems.

Keywords: genetic algorithm, load-balancing algorithm, optimal variation, local optimization

Procedia PDF Downloads 185