Search results for: deterioration modeling

Authors: John Knight, Fuchun Li, Yan Xu

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Based on a new method of the nonparametric estimator of the drift function, we propose a consistent test for the parametric specification of the drift function in the short rate diffusion process using observations from a panel of yields. The test statistic is shown to follow an asymptotic normal distribution under the null hypothesis that the parametric drift function is correctly specified, and converges to infinity under the alternative. Taking the daily 7-day European rates as a proxy of the short rate, we use our test to examine whether the drift of the short rate diffusion process is linear or nonlinear, which is an unresolved important issue in the short rate modeling literature. The testing results indicate that none of the drift functions in this literature adequately captures the dynamics of the drift, but nonlinear specification performs better than the linear specification.

Keywords: diffusion process, nonparametric estimation, derivative security price, drift function and volatility function

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Authors: Omid Shahmirzadi, Adam Lugowski, Kenneth Younge

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Automatic measurement of semantic text similarity is an important task in natural language processing. In this paper, we evaluate the performance of different vector space models to perform this task. We address the real-world problem of modeling patent-to-patent similarity and compare TFIDF (and related extensions), topic models (e.g., latent semantic indexing), and neural models (e.g., paragraph vectors). Contrary to expectations, the added computational cost of text embedding methods is justified only when: 1) the target text is condensed; and 2) the similarity comparison is trivial. Otherwise, TFIDF performs surprisingly well in other cases: in particular for longer and more technical texts or for making finer-grained distinctions between nearest neighbors. Unexpectedly, extensions to the TFIDF method, such as adding noun phrases or calculating term weights incrementally, were not helpful in our context.

Keywords: big data, patent, text embedding, text similarity, vector space model

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Authors: Daniel Mokatsanyane, Johnny Jansen Van Rensburg

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This paper is a concise introduction of the risk management on the water derivatives market. Water, a new commodity in the market, is one of the most important commodity on earth. As important to life and planet as crops, metals, and energy, none of them matters without water. This paper presents a brief overview of water as a tradable commodity via a new first of its kind futures contract on the Nasdaq Veles California Water Index (NQH2O) derivative instrument, TheGeneralised Autoregressive Conditional Heteroscedasticity (GARCH) statistical model will be the used to measure the water price volatility of the instrument and its performance since it’s been traded. describe the main products and illustrate their usage in risk management and also discuss key challenges with modeling and valuation of water as a traded commodity and finally discuss how water derivatives may be taken as an alternative asset investment class.

Keywords: water derivatives, commodity market, nasdaq veles california water Index (NQH2O, water price, risk management

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Authors: Jamal Takhchi

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The understanding of vibration propagation in complex structures such as automotive body in white remains a challenging issue in car design regarding NVH performances. The current analysis is limited to the low frequency range where modal concepts are dominant. Higher frequencies, between 200 and 1000 Hz, will become critical With the rise of electrification. EVs annoying sounds are mostly whines created by either Gears or e-motors between 300 Hz and 2 kHz. Structural intensity analysis was Experienced a few years ago on finite element models. The application was promising but limited by the fact that the propagating 3D intensity vector field is masked by a rotational Intensity field. This rotational field should be filtered using a differential operator. The expression of this operator in the framework of finite element modeling is not yet known. The aim of the proposed work is to implement this operator in the current dynamic solver (NASTRAN) of Stellantis and develop the Expected methodology for the mid-frequency structural analysis of electrified vehicles.

Keywords: structural intensity, NVH, body in white, irrotatational intensity

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Authors: D. Y. Fong, C. Y. Kuo, Y. T. Chiang, W. C. Lin

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Objectives: Qigong is an ancient Chinese practice in pursuit of a healthier body and a more peaceful mindset. It emphasizes on the restoration of vital energy (Qi) in body, mind, and spirit. The practice is the combination of gentle movements and mild breathing which help the doers reach the condition of tranquility. On account of the features of Qigong, first, we use cross-sectional methodology to compare the differences among the varied levels of Qigong practitioners on cognitive function with event-related potential (ERP) and electroencephalography (EEG). Second, we use the longitudinal methodology to explore the effects on the Qigong trainees for pretest and posttest on ERP and EEG. Current study adopts Attentional Network Test (ANT) task to examine the participants’ cognitive function, and aging-related researches demonstrated a declined tread on the cognition in older adults and exercise might ameliorate the deterioration. Qigong exercise integrates physical posture (muscle strength), breathing technique (aerobic ability) and focused intention (attention) that researchers hypothesize it might improve the cognitive function in aging adults. Method: Sixty participants were involved in this study, including 20 young adults (21.65±2.41 y) with normal physical activity (YA), 20 Qigong experts (60.69 ± 12.42 y) with over 7 years Qigong practice experience (QE), and 20 normal and healthy adults (52.90±12.37 y) with no Qigong practice experience as experimental group (EG). The EG participants took Qigong classes 2 times a week and 2 hours per time for 24 weeks with the purpose of examining the effect of Qigong intervention on cognitive function. ANT tasks (alert network, orient network, and executive control) were adopted to evaluate participants’ cognitive function via ERP’s P300 components and P300 amplitude topography. Results: Behavioral data: 1.The reaction time (RT) of YA is faster than the other two groups, and EG was faster than QE in the cue and flanker conditions of ANT task. 2. The RT of posttest was faster than pretest in EG in the cue and flanker conditions. 3. No difference among the three groups on orient, alert, and execute control networks. ERP data: 1. P300 amplitude detection in QE was larger than EG at Fz electrode in orient, alert, and execute control networks. 2. P300 amplitude in EG was larger at pretest than posttest on the orient network. 3. P300 Latency revealed no difference among the three groups in the three networks. Conclusion: Taken together these findings, they provide neuro-electrical evidence that older adults involved in Qigong practice may develop a more overall compensatory mechanism and also benefit the performance of behavior.

Keywords: Qigong, cognitive function, aging, event-related potential (ERP)

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Authors: Markus Mazzola, Gunther Schaaf

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A vehicle driving with an Adaptive Cruise Control System (ACC) is usually controlled decentrally, based on the information of radar systems and in some publications based on C2X-Communication (CACC) to guarantee stable platoons. In this paper, we present a Model Predictive Control (MPC) design of a centralized, server-based ACC-System, whereby the vehicular platoon is modeled and controlled as a whole. It is then proven that the proposed MPC design guarantees asymptotic stability and hence string stability of the platoon. The Networked MPC design is chosen to be able to integrate system constraints optimally as well as to reduce the effects of communication delay and packet loss. The performance of the proposed controller is then simulated and analyzed in an LTE communication scenario using the LTE/EPC Network Simulator LENA, which is based on the ns-3 network simulator.

Keywords: adaptive cruise control, centralized server, networked model predictive control, string stability

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Authors: Mohamed Haffar, Khalil Al-Hyari, Mohammed Khair Abu Zaid, Ramadane Djbarni, Mohammed Hamdan

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While employee readiness for change (ERFC) is recognised as critical for total quality management (TQM) implementation, there is a lack of systematic and empirical studies regarding the relationship between ERFC dimensions and TQM. Therefore, this study proposes to fill this gap by providing empirical evidence leading to advancement in the understanding of the influences of ERFC components on TQM implementation. The empirical data for this study was drawn from a survey of 400 middle and senior managers of Jordanian firms. The analysis of the collected data, which was conducted using Structural Equation Modeling technique, revealed that three of the ERFC components, namely personally beneficial, change self-efficacy and management support are the most supportive ERFC dimensions for TQM implementation. Therefore, this paper makes a novel contribution by providing a refined and deeper comprehension of the relationships between ERFCs and TQM implementation.

Keywords: total quality management, employee readiness for change, manufacturing organisations, Jordan

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Authors: G. Carrero, C. Contreras, M. J. Hendzel

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Linker histones or histones H1 are highly mobile nuclear proteins that regulate the organization of chromatin and limit DNA accessibility by binding to the chromatin structure (DNA and associated proteins). It is known that this binding process is driven by both slow (strong binding) and rapid (weak binding) interactions. However, the exact binding mechanism has not been fully described. Moreover, the existing models only account for one type of bound population that does not distinguish explicitly between the weakly and strongly bound proteins. Thus, we propose different systems of reaction-diffusion equations to describe explicitly the rapid and slow interactions during a FRAP (Fluorescence Recovery After Photobleaching) experiment. We perform a model comparison analysis to characterize the binding mechanism of histone H1 and provide new meaningful biophysical information on the kinetics of histone H1.

Keywords: FRAP (Fluorescence Recovery After Photobleaching), histone H1, histone H1 binding kinetics, linker histone, reaction-diffusion equation

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Authors: Said Ettaieb, Kamel Hamrouni, Su Ruan

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This paper presents a new method based both on Active Shape Model and a priori knowledge about the spatio-temporal shape variation for tracking deformable structures in medical imaging. The main idea is to exploit the a priori knowledge of shape that exists in ASM and introduce new knowledge about the shape variation over time. The aim is to define a new more stable method, allowing the reliable detection of structures whose shape changes considerably in time. This method can also be used for the three-dimensional segmentation by replacing the temporal component by the third spatial axis (z). The proposed method is applied for the functional and morphological study of the heart pump. The functional aspect was studied through temporal sequences of scintigraphic images and morphology was studied through MRI volumes. The obtained results are encouraging and show the performance of the proposed method.

Keywords: active shape model, a priori knowledge, spatiotemporal shape variation, deformable structures, medical images

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Authors: Sachin Kamble, Shradha Gawankar

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This paper presents the findings of successful implementation of Business Process Reengineering (BPR) of cement dispatch activities in a cement manufacturing plant located in India. Simulation model was developed for the purpose of identifying and analyzing the areas for improvement. The company was facing a problem of low throughput rate and subsequent forced stoppages of the plant leading to a high production loss of 15000MT per month. It was found from the study that the present systems and procedures related to the in-plant logistics plant required significant changes. The major recommendations included process improvement at the entry gate, reducing the cycle time at the security gate and installation of an additional weigh bridge. This paper demonstrates how BPR can be implemented for improving the in-plant logistics process. Various recommendations helped the plant to increase its throughput by 14%.

Keywords: in-plant logistics, cement logistics, simulation modelling, business process re-engineering, supply chain management

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Authors: M. Brandt, A. Peniak, J. Makarovič, P. Rafajdus

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This paper deals with a novel approach of power transformers diagnostics. This approach identifies the exact location and the range of a fault in the transformer and helps to reduce operation costs related to handling of the faulty transformer, its disassembly and repair. The advantage of the approach is a possibility to simulate healthy transformer and also all faults, which can occur in transformer during its operation without its disassembling, which is very expensive in practice. The approach is based on creating frequency dependent impedance of the transformer by sweep frequency response analysis measurements and by 3D FE parametrical modeling of the fault in the transformer. The parameters of the 3D FE model are the position and the range of the axial short circuit. Then, by comparing the frequency dependent impedances of the parametrical models with the measured ones, the location and the range of the fault is identified. The approach was tested on a real transformer and showed high coincidence between the real fault and the simulated one.

Keywords: transformer, parametrical model of transformer, fault, sweep frequency response analysis, finite element method

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Authors: C. Pislaru, A. Shebani

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This paper uses the radial basis function neural network (RBFNN) for system identification of nonlinear systems. Five nonlinear systems are used to examine the activity of RBFNN in system modeling of nonlinear systems; the five nonlinear systems are dual tank system, single tank system, DC motor system, and two academic models. The feed forward method is considered in this work for modelling the non-linear dynamic models, where the K-Means clustering algorithm used in this paper to select the centers of radial basis function network, because it is reliable, offers fast convergence and can handle large data sets. The least mean square method is used to adjust the weights to the output layer, and Euclidean distance method used to measure the width of the Gaussian function.

Keywords: system identification, nonlinear systems, neural networks, radial basis function, K-means clustering algorithm

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Authors: Aline F. Marcon, Eduardo F. da Silva, Marina Bouzon

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The impact of lean management on environmental sustainability is the research line that receives the most attention from academicians. Therefore, the social dimension of sustainable development has so far received less attention. This paper aims to evaluate the impact of intra-plant lean manufacturing practices on social sustainability indicators extracted from the Global Reporting Initiative (GRI) parameters. The method is two-phased, including MCDM approach to uncover the most relevant practices regarding social performance and Interpretive Structural Modeling (ISM) method to reveal the structural relationship among lean practices. Professionals from the academic and industrial fields answered the questionnaires. From the results of this paper, it is possible to verify that practices such as “Safety Improvement Programs”, “Total Quality Management” and “Cross-functional Workforce” are the ones which have the most positive influence on the set of GRI social indicators.

Keywords: indicators, ISM, lean, social, sustainability

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Authors: H. Golchoobian, M. H. Taheri, S. Saedodin, A. Sarafraz

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This paper investigates the possibility of using three systems of organic Rankine auxiliary power generation, ejector refrigeration and absorption to recover energy from a diesel car. The analysis is done for both urban and suburban driving modes that vary from 60 to 120 km/h. Various refrigerants have also been used for organic Rankine and Ejector refrigeration cycles. The capacity was evaluated by Organic Rankine Cycle (ORC) system in both urban and suburban conditions for cyclopentane and ammonia as refrigerants. Also, for these two driving plans, produced cooling by absorption refrigeration system under variable ambient temperature conditions and in ejector refrigeration system for R123, R134a and R141b refrigerants were investigated.

Keywords: absorption system, diesel engine, ejector refrigeration, energy recovery, organic Rankine cycle

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Authors: Jeremiah Mutamba

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Water is a critical resource for sustainable economic growth and social development. It enables societies to thrive and influences every urban center’s future. Thus, water must always be available in the right quantity and quality. However, in South Africa - a known physically water scarce nation – the future of sustainable urban supply of water may be in jeopardy. The country facing a water crisis influenced by insufficient infrastructure investment and maintenance, recurrent droughts and climate variation, human induced water quality deterioration, as well as growing lack of technical capacity in water institutions, particularly local municipalities. Aside of the eight metropolitan municipalities for the country, most municipalities struggle with provision of reliable water to their citizens. These municipalities contend with having now capable engineers, aging infrastructure with concomitant high system water losses (of 30% and upwards), coupled with growing water demand from expanding industries and population growth. Also, a significant portion (44%) of national water treatment plants are in critically poor condition, requiring urgent rehabilitation. Municipalities also struggle to raise funding to instate projects. All these factors militate against sustainable urban water supply in the country. Urgent mitigation measures are required. This paper seeks to review the extent of the current water supply challenges in South Africa’s urban centers, including searching for practical and cost-effective measures. The study followed a qualitative approach, combining desktop literature research, interviews with key sector stakeholders, and a workshop. Phenomenological data analysis technique was used to study and examine interview data and secondary desktop data. Preliminary findings established the building of technical or engineering capacity, reversal of the high physical water losses, rehabilitation of poor condition and dysfunctional water treatment works, diversification of water resource mix, and water scarcity awareness programs as possible practical solutions. Other proposed solutions include the use of performance-based or value-based contracting to fund initiatives to reduce high system water losses. Out-come based arrangements for revenue increasing water loss reduction projects were considered more practical in funding-stressed local municipalities. If proactively implemented in an integrated manner, these proposed solutions are likely to ensure sustainable urban water supply in South African urban centers in the future.

Keywords: sustainable, water scarcity, water supply, South Africa

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Authors: Chawarat Rotejanaprasert, Andrew Lawson

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Early detection of unusual health events depends on the ability to detect rapidly any substantial changes in disease, thus facilitating timely public health interventions. To assist public health practitioners to make decisions, statistical methods are adopted to assess unusual events in real time. We introduce a surveillance Kullback-Leibler (SKL) measure for timely detection of disease outbreaks for small area health data. The detection methods are compared with the surveillance conditional predictive ordinate (SCPO) within the framework of Bayesian hierarchical Poisson modeling and applied to a case study of a group of respiratory system diseases observed weekly in South Carolina counties. Properties of the proposed surveillance techniques including timeliness and detection precision are investigated using a simulation study.

Keywords: Bayesian, spatial, temporal, surveillance, prospective

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Authors: Laidi Maamar, Hanini Salah

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The present work investigates the potential of artificial neural network (ANN) model to predict the horizontal global solar radiation (HGSR). The ANN is developed and optimized using three years meteorological database from 2011 to 2013 available at the meteorological station of Blida (Blida 1 university, Algeria, Latitude 36.5°, Longitude 2.81° and 163 m above mean sea level). Optimal configuration of the ANN model has been determined by minimizing the Root Means Square Error (RMSE) and maximizing the correlation coefficient (R2) between observed and predicted data with the ANN model. To select the best ANN architecture, we have conducted several tests by using different combinations of parameters. A two-layer ANN model with six hidden neurons has been found as an optimal topology with (RMSE=4.036 W/m²) and (R²=0.999). A graphical user interface (GUI), was designed based on the best network structure and training algorithm, to enhance the users’ friendliness application of the model.

Keywords: artificial neural network, global solar radiation, solar energy, prediction, Algeria

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Authors: Liyew Yizengaw Yitayih

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This nanotechnology study focuses on how potassium ions (K+) affect lithium-ion (Li-ion) battery performance. By adding potassium ions (K+) to the lithium tin oxide (LiSnO) anode and employing styrene-butadiene rubber (SBR) as a binder, the doping of K+ was specifically studied. The methods employed in this study include computer modeling and simulation, material fabrication, and electrochemical characterization. The potassium ions (Li+) were successfully doped into the LiSnO lattice during charge/discharge cycles, which increased the lithium-ion diffusivity and electrical conductivity within the anode. However, it was found that internal doping of potassium ions (K+) into the LiSnO lattice occurred at high potassium ion concentrations (>16.6%), which hampered lithium ion transfer because of repulsion and physical blockage. The electrochemical efficiency of lithium-ion batteries was improved by this comprehensive study's presentation of potassium ions' (K+) potential advantages when present in the appropriate concentrations in electrode materials.

Keywords: lithium-ion battery, LiSnO anode, potassium doping, lithium-ion diffusivity, electronic conductivity

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Authors: O. Ahmed Apampa, Yinusa, A. Jimoh

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The aim of this study was to develop an appropriate model for predicting the compaction behavior of lateritic soils and corn cob ash (CCA) stabilized lateritic soils. This was done by first adopting an equation earlier developed for fine-grained soils and subsequent adaptation by others and extending it to modified lateritic soil through the introduction of alpha and beta parameters which are polynomial functions of the CCA binder input. The polynomial equations were determined with MATLAB R2011 curve fitting tool, while the alpha and beta parameters were determined by standard linear programming techniques using the Solver function of Microsoft Excel 2010. The model so developed was a good fit with a correlation coefficient R2 value of 0.86. The paper concludes that it is possible to determine the optimum moisture content and the maximum dry density of CCA stabilized soils from the compaction test of the unmodified soil, and recommends that this procedure is extended to other binder stabilized lateritic soils to facilitate quick decision making in roadworks.

Keywords: compaction, corn cob ash, lateritic soil, stabilization

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Authors: Gokul Prasad, Pennan Chinnasamy

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The degradation of groundwater resources, attributed to factors such as excessive abstraction and contamination, has emerged as a global concern. This study delves into the stable isotopes of water) in a hard-rock aquifer situated in the Upper Godavari watershed, an agriculturally rich region in India underlain by Basalt. The higher groundwater draft (> 90%) poses significant risks; comprehending groundwater sources, flow patterns, and their environmental impacts is pivotal for researchers and water managers. The region has faced five droughts in the past 20 years; four are categorized as medium. The recharge rates are variable and show a very minimum contribution to groundwater. The rainfall pattern shows vast variability, with the region receiving seasonal monsoon rainfall for just four months and the rest of the year experiencing minimal rainfall. This research closely monitored monsoon precipitation inputs and examined spatial and temporal fluctuations in δ18O and δ2H in both groundwater and precipitation. By discerning individual recharge events during monsoons, it became possible to identify periods when evaporation led to groundwater quality deterioration, characterized by elevated salinity and stable isotope values in the return flow. The locally derived meteoric water line (LMWL) (δ2H = 6.72 * δ18O + 1.53, r² = 0.6) provided valuable insights into the groundwater system. The leftward shift of the Nashik LMWL in relation to the GMWL and LMWL indicated groundwater evaporation (-33 ‰), supported by spatial variations in electrical conductivity (EC) data. Groundwater in the eastern and northern watershed areas exhibited higher salinity > 3000uS/cm, expanding > 40% of the area compared to the western and southern regions due to geological disparities (alluvium vs basalt). The findings emphasize meteoric precipitation as the primary groundwater source in the watershed. However, spatial variations in isotope values and chemical constituents indicate other contributing factors, including evaporation, groundwater source type, and natural or anthropogenic (specifically agricultural and industrial) contaminants. Therefore, the study recommends focused hydro geochemistry and isotope analysis in areas with strong agricultural and industrial influence for the development of holistic groundwater management plans for protecting the groundwater aquifers' quantity and quality.

Keywords: groundwater quality, stable isotopes, salinity, groundwater management, hard-rock aquifer

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Authors: Ch. Sridevi, S. P. Shailender Kumar, B. Gurudayal, A. Chalapathi Rao, K. Koteswara Rao, P. Srinivasulu

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System reliability and system availability evaluation plays a crucial role in ensuring the seamless operation of complex satellite data reception system with consistent performance for longer periods. This paper presents a novel approach for the same using a case study on one of the antenna systems at satellite data reception ground station in India. The methodology involves analyzing system's components, their failure rates, system's architecture, generation of logical reliability block diagram model and estimating the reliability of the system using the component level mean time between failures considering exponential distribution to derive a baseline estimate of the system's reliability. The model is then validated with collected system level field failure data from the operational satellite data reception systems that includes failure occurred, failure time, criticality of the failure and repair times by using statistical techniques like median rank, regression and Weibull analysis to extract meaningful insights regarding failure patterns and practical reliability of the system and to assess the accuracy of the developed reliability model. The study mainly focused on identification of critical units within the system, which are prone to failures and have a significant impact on overall performance and brought out a reliability model of the identified critical unit. This model takes into account the interdependencies among system components and their impact on overall system reliability and provides valuable insights into the performance of the system to understand the Improvement or degradation of the system over a period of time and will be the vital input to arrive at the optimized design for future development. It also provides a plug and play framework to understand the effect on performance of the system in case of any up gradations or new designs of the unit. It helps in effective planning and formulating contingency plans to address potential system failures, ensuring the continuity of operations. Furthermore, to instill confidence in system users, the duration for which the system can operate continuously with the desired level of 3 sigma reliability was estimated that turned out to be a vital input to maintenance plan. System availability and station availability was also assessed by considering scenarios of clash and non-clash to determine the overall system performance and potential bottlenecks. Overall, this paper establishes a comprehensive methodology for reliability and availability analysis of complex satellite data reception systems. The results derived from this approach facilitate effective planning contingency measures, and provide users with confidence in system performance and enables decision-makers to make informed choices about system maintenance, upgrades and replacements. It also aids in identifying critical units and assessing system availability in various scenarios and helps in minimizing downtime and optimizing resource allocation.

Keywords: exponential distribution, reliability modeling, reliability block diagram, satellite data reception system, system availability, weibull analysis

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Authors: Maria Valeria De Bonis, Gianpaolo Ruocco

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Nowadays, computational modeling is paving new design and verification ways in a number of industrial sectors. The technology is ripe to challenge some case in the Bioengineering and Medicine frameworks: for example, looking at the strategical and ethical importance of oncology research, efforts should be made to yield new and powerful resources to tumor knowledge and understanding. With these driving motivations, we approach this gigantic problem by using some standard engineering tools such as the mathematics behind the biomass transfer. We present here some bacterial colonization studies in complex structures. As strong analogies hold with some tumor proliferation, we extend our study to a benchmark case of solid tumor. By means of a commercial software, we model biomass and energy evolution in arbitrary media. The approach will be useful to cast virtualization cases of cancer growth in human organs, while augmented reality tools will be used to yield for a realistic aid to informed decision in treatment and surgery.

Keywords: bacteria, simulation, tumor, precision medicine

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Authors: V. D. Thi, M. Li, M. Khelifa, M. El Ganaoui, Y. Rogaume

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This paper presents a two-dimensional model to study the heat and moisture transfer through porous building materials. Dynamic and static coupled models of heat and moisture transfer in porous material under low temperature are presented and the coupled models together with variable initial and boundary conditions have been considered in an analytical way and using the finite element method. The resulting coupled model is converted to two nonlinear partial differential equations, which is then numerically solved by an implicit iterative scheme. The numerical results of temperature and moisture potential changes are compared with the experimental measurements available in the literature. Predicted results demonstrate validation of the theoretical model and effectiveness of the developed numerical algorithms. It is expected to provide useful information for the porous building material design based on heat and moisture transfer model.

Keywords: finite element method, heat transfer, moisture transfer, porous materials, wood

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Authors: B. Razmi, F. Rafiee, M. Baziar, A. Saeedi Azizkandi

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In the present research, a series of 3-D finite element numerical modeling was performed to study the effect of system frequency and excitation specifications on the internal forces of the piled raft (PR) system in a dry sand layer. The results of numerical simulations were first compared with those associated with centrifuge tests. The natural frequency of superstructure, modeled on the piled raft foundation, was smaller than the natural frequency of the fixed-base super-structure. This difference was greater for super-structures with higher frequencies. In PR systems, the excitation with a frequency close to the system frequency produced the largest responses. Furthermore, based on the results of presented numerical analyses, ignoring the interactions and characteristics of all components of a pile-raft-structure, may lead to highly uneconomical design.

Keywords: centrifuge test, excitation frequency, natural frequency of super-structure, piled raft foundation, 3-D finite element model

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Authors: Shailaja Grover, Purvi Tiwari, Vigneshwaran S. R., U. Dinesh Kumar

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In India, grapes are one of the most important horticulture crops. Grapes are most vulnerable to downy mildew, which is one of the most devasting diseases. In the absence of a precise weather-based advisory system, farmers spray pesticides on their crops extensively. There are two main challenges associated with using these pesticides. Firstly, most of these sprays were panic sprays, which could have been avoided. Second, farmers use more expensive "Preventive and Eradicate" chemicals than "Systemic, Curative and Anti-sporulate" chemicals. When these chemicals are used indiscriminately, they can enter the fruit and cause health problems such as cancer. This paper utilizes decision trees and predictive modeling techniques to provide grape farmers with customized advice on grape disease management. This model is expected to reduce the overall use of chemicals by approximately 50% and the cost by around 70%. Most of the grapes produced will have relatively low residue levels of pesticides, i.e., below the permissible level.

Keywords: analytics in agriculture, downy mildew, weather based advisory, decision tree, predictive modelling

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Authors: N. P. Yadav, Deepti Verma

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This paper focuses on the mathematical modeling for solidification of Al alloy in a cube mould cavity to study the solidification behavior of casting process. The parametric investigation of solidification process inside the cavity was performed by using computational solidification/melting model coupled with Volume of fluid (VOF) model. The implicit filling algorithm is used in this study to understand the overall process from the filling stage to solidification in a model metal casting process. The model is validated with past studied at same conditions. The solidification process are analyzed by including the effect of pouring velocity and temperature of liquid metal, effect of wall temperature as well natural convection from the wall and geometry of the cavity. These studies show the possibility of various defects during solidification process.

Keywords: buoyancy driven flow, natural convection driven flow, residual flow, secondary flow, volume of fluid

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Authors: Soheil Mohtaram, Wu Weidong, Yashar Aryanfar

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This research investigates the points with heat recovery potential in a triple-pressure cogeneration combined cycle power plant and determines the amount of waste heat that can be recovered. A modified cycle arrangement is then adopted for accessing thermal potentials. Modeling the energy system is followed by thermodynamic and energetic evaluation, and then the price of the manufactured products is also determined using the Total Revenue Requirement (TRR) method and term economic analysis. The results of optimization are then presented in a Pareto chart diagram by implementing a new model with dual objective functions, which include power cost and produce heat. This model can be utilized to identify the optimal operating point for such power plants based on electricity and heat prices in different regions.

Keywords: heat loss, recycling, unused energy, efficient production, optimization, triple-pressure cogeneration

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Authors: Ihsane Modhaffar, Kamal Gueraoui, Abouelkacem Qais, Abderrahmane Maaouni, Samir Men-La-Yakhaf, Hamid Eltourroug

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The main objective of this paper is to develop a Computational Fluid Dynamics (CFD) model to simulate and characterize the fiber suspension in flow in rectangular cavities. The model is intended to describe the velocity profile and to predict the fiber orientation. The flow was considered to be incompressible, and behave as Newtonian fluid containing suspensions of short-fibers. The numerical model for determination of velocity profile and fiber orientation during mold-filling stage of injection molding process was solved using finite volume method. The governing equations of this problem are: the continuity, the momentum and the energy. The obtained results were compared to available experimental findings. A good agreement between the numerical results and the experimental data was achieved.

Keywords: injection, composites, short-fiber reinforced thermoplastics, fiber orientation, incompressible fluid, numerical simulation

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Authors: N. G. Thangan, A. B. Deoghare, P. M. Padole

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Computational Fluid Dynamics (CFD) aids in modeling the prototype of a real world processes. CFD approach is useful in predicting the fluid flow, heat transfer mass transfer and other flow related phenomenon. In present study, hydrodynamic characteristics of gas-solid cylindrical fluidized bed is compared with conical fluidized beds. A 2D fluidized bed consists of different configurations of particle size of iron oxide, bed height and superficial velocities of nitrogen. Simulations are performed to capture the complex physics associated with it. The Eulerian multiphase model is prepared in ANSYS FLUENT v.14 which is used to simulate fluidization process. It is analyzed with nitrogen as primary phase and iron oxide as secondary phase. The bed hydrodynamics is assessed prominently to examine effect on fluidization time, pressure drop, minimum fluidization velocity, and gas holdup in the system.

Keywords: fluidized bed, bed hydrodynamics, Eulerian multiphase approach, computational fluid dynamics

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Authors: Sameerah A. Al-Hariri Al-Zahrani

Abstract:

The current study aims at getting acquainted with the impact of the use of some multiple intelligence-based teaching strategies on developing moral intelligence and inferential jurisprudential thinking among secondary school female students. The study has endeavored to answer the following questions: What is the impact of the use of some multiple intelligence-based teaching strategies on developing inferential jurisprudential thinking and moral intelligence among first-year secondary school female students? In the frame of this main research question, the study seeks to answer the following sub-questions: (i) What are the inferential jurisprudential thinking skills among first-year secondary school female students? (ii) What are the components of moral intelligence among first year secondary school female students? (iii) What is the impact of the use of some multiple intelligence‐based teaching strategies (such as the strategies of analyzing values, modeling, Socratic discussion, collaborative learning, peer collaboration, collective stories, building emotional moments, role play, one-minute observation) on moral intelligence among first-year secondary school female students? (iv) What is the impact of the use of some multiple intelligence‐based teaching strategies (such as the strategies of analyzing values, modeling, Socratic discussion, collaborative learning, peer collaboration, collective stories, building emotional moments, role play, one-minute observation) on developing the capacity for inferential jurisprudential thinking of juristic rules among first-year secondary school female students? The study has used the descriptive-analytical methodology in surveying, analyzing, and reviewing the literature on previous studies in order to benefit from them in building the tools of the study and the materials of experimental treatment. The study has also used the experimental method to study the impact of the independent variable (multiple intelligence strategies) on the two dependent variables (moral intelligence and inferential jurisprudential thinking) in first-year secondary school female students’ learning. The sample of the study is made up of 70 female students that have been divided into two groups: an experimental group consisting of 35 students who have been taught through multiple intelligence strategies, and a control group consisting of the other 35 students who have been taught normally. The two tools of the study (inferential jurisprudential thinking test and moral intelligence scale) have been implemented on the two groups as a pre-test. The female researcher taught the experimental group and implemented the two tools of the study. After the experiment, which lasted eight weeks, was over, the study showed the following results: (i) The existence of significant statistical differences (0.05) between the mean average of the control group and that of the experimental group in the inferential jurisprudential thinking test (recognition of the evidence of jurisprudential rule, recognition of the motive for the jurisprudential rule, jurisprudential inferencing, analogical jurisprudence) in favor of the experimental group. (ii) The existence of significant statistical differences (0.05) between the mean average of the control group and that of the experimental group in the components of the moral intelligence scale (sympathy, conscience, moral wisdom, tolerance, justice, respect) in favor of the experimental group. The study has, thus, demonstrated the impact of the use of some multiple intelligence-based teaching strategies on developing moral intelligence and inferential jurisprudential thinking.

Keywords: moral intelligence, teaching, inferential jurisprudential thinking, secondary school

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