Search results for: oilfield scales
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 863

Search results for: oilfield scales

473 Solar Wind Turbulence and the Role of Circularly Polarized Dispersive Alfvén Wave

Authors: Swati Sharma, R. P. Sharma

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We intend to study the nonlinear evolution of the parallel propagating finite frequency Alfvén wave (also called Dispersive Alfvén wave/Hall MHD wave) propagating in the solar wind regime of the solar region when a perpendicularly propagating magnetosonic wave is present in the background. The finite frequency Alfvén wave behaves differently from the usual non-dispersive behavior of the Alfvén wave. To study the nonlinear processes (such as filamentation) taking place in the solar regions such as solar wind, the dynamical equation of both the waves are derived. Numerical simulation involving finite difference method for the time domain and pseudo spectral method for the spatial domain is then performed to analyze the transient evolution of these waves. The power spectra of the Dispersive Alfvén wave is also investigated. The power spectra shows the distribution of the magnetic field intensity of the Dispersive Alfvén wave over different wave numbers. For DAW the spectra shows a steepening for scales larger than the proton inertial length. This means that the wave energy gets transferred to the solar wind particles as the wave reaches higher wave numbers. This steepening of the power spectra can be explained on account of the finite frequency of the Alfvén wave. The obtained results are consistent with the observations made by CLUSTER spacecraft.

Keywords: solar wind, turbulence, dispersive alfven wave

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472 Long Waves Inundating through and around an Array of Circular Cylinders

Authors: Christian Klettner, Ian Eames, Tristan Robinson

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Tsunami is characterised by their very long time periods and can have devastating consequences when these inundate through built-up coastal regions as in the 2004 Indian Ocean and 2011 Tohoku Tsunami. This work aims to investigate the effect of these long waves on the flow through and around a group of buildings, which are abstracted to circular cylinders. The research approach used in this study was using experiments and numerical simulations. Large-scale experiments were carried out at HR Wallingford. The novelty of these experiments is (I) the number of bodies present (up to 64), (II) the long wavelength of the input waves (80 seconds) and (III) the width of the tank (4m) which gives the unique opportunity to investigate three length scales, namely the diameter of the building, the diameter of the array and the width of the tank. To complement the experiments, dam break flow past the same arrays is investigated using three-dimensional numerical simulations in OpenFOAM. Dam break flow was chosen as it is often used as a surrogate for the tsunami in previous research and is used here as there are well defined initial conditions and high quality previous experimental data for the case of a single cylinder is available. The focus of this work is to better understand the effect of the solid void fraction on the force and flow through and around the array. New qualitative and quantitative diagnostics are developed and tested to analyse the complex coupled interaction between the cylinders.

Keywords: computational fluid dynamics, tsunami, forces, complex geometry

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471 The Cartometric-Geographical Analysis of Ivane Javakhishvili 1922: The Map of the Republic of Georgia

Authors: Manana Kvetenadze, Dali Nikolaishvili

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The study revealed the territorial changes of Georgia before the Soviet and Post-Soviet periods. This includes the estimation of the country's borders, its administrative-territorial arrangement change as well as the establishment of territorial losses. Georgia’s old and new borders marked on the map are of great interest. The new boundary shows the condition of 1922 year, following the Soviet period. Neither on this map nor in other works Ivane Javakhishvili talks about what he implies in the old borders, though it is evident that this is the Pre-Soviet boundary until 1921 – i.e., before the period when historical Tao, Zaqatala, Lore, Karaia represented the parts of Georgia. According to cartometric-geographical terms, the work presents detailed analysis of Georgia’s borders, along with this the comparison of research results has been carried out: 1) At the boundary line on Soviet topographic maps, the maps of 100,000; 50,000 and 25,000 scales are used; 2) According to Ivane Javakhishvili’s work ('The borders of Georgia in terms of historical and contemporary issues'). During that research, we used multi-disciplined methodology and software. We used Arc GIS for Georeferencing maps, and after that, we compare all post-Soviet Union maps, in order to determine how the borders have changed. During this work, we also use many historical data. The features of the spatial distribution of the territorial administrative units of Georgia, as well as the distribution of administrative-territorial units of the objects depicted on the map, have been established. The results obtained are presented in the forms of thematic maps and diagrams.

Keywords: border, GIS, georgia, historical cartography, old maps

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470 Performance Improvement of SOI-Tri Gate FinFET Transistor Using High-K Dielectric with Metal Gate

Authors: Fatima Zohra Rahou, A.Guen Bouazza, B. Bouazza

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SOI TRI GATE FinFET transistors have emerged as novel devices due to its simple architecture and better performance: better control over short channel effects (SCEs) and reduced power dissipation due to reduced gate leakage currents. As the oxide thickness scales below 2 nm, leakage currents due to tunneling increase drastically, leading to high power consumption and reduced device reliability. Replacing the SiO2 gate oxide with a high-κ material allows increased gate capacitance without the associated leakage effects. In this paper, SOI TRI-GATE FinFET structure with use of high K dielectric materials (HfO2) and SiO2 dielectric are simulated using the 3-D device simulator Devedit and Atlas of TCAD Silvaco. The simulated results exhibits significant improvements in the performances of SOI TRI GATE FinFET with gate oxide HfO2 compared with conventional gate oxide SiO2 for the same structure. SOI TRI-GATE FinFET structure with the use of high K materials (HfO2) in gate oxide results into the increase in saturation current, threshold voltage, on-state current and Ion/Ioff ratio while off-state current, subthreshold slope and DIBL effect are decreased.

Keywords: technology SOI, short-channel effects (SCEs), multi-gate SOI MOSFET, SOI-TRI Gate FinFET, high-K dielectric, Silvaco software

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469 Defining the Turbulent Coefficients with the Effect of Atmospheric Stability in Wake of a Wind Turbine Wake

Authors: Mohammad A. Sazzad, Md M. Alam

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Wind energy is one of the cleanest form of renewable energy. Despite wind industry is growing faster than ever there are some roadblocks towards the improvement. One of the difficulties the industry facing is insufficient knowledge about wake within the wind farms. As we know energy is generated in the lowest layer of the atmospheric boundary layer (ABL). This interaction between the wind turbine (WT) blades and wind introduces a low speed wind region which is defined as wake. This wake region shows different characteristics under each stability condition of the ABL. So, it is fundamental to know this wake region well which is defined mainly by turbulence transport and wake shear. Defining the wake recovery length and width are very crucial for wind farm to optimize the generation and reduce the waste of power to the grid. Therefore, in order to obtain the turbulent coefficients of velocity and length, this research focused on the large eddy simulation (LES) data for neutral ABL (NABL). According to turbulent theory, if we can present velocity defect and Reynolds stress in the form of local length and velocity scales, they become invariant. In our study velocity and length coefficients are 0.4867 and 0.4794 respectively which is close to the theoretical value of 0.5 for NABL. There are some invariant profiles because of the presence of thermal and wind shear power coefficients varied a little from the ideal condition.

Keywords: atmospheric boundary layer, renewable energy, turbulent coefficient, wind turbine, wake

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468 The Internal Migration in Jiangxi Province, China after the Migrating Decision

Authors: Gourida Siham

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Chinese society has witnessed a continuing trend of nationwide rural to urban migration since the 1970's. Before that age, under restricted hukou systems, peasants were kept still and fixed in the farm land. The year 1978 and later years saw the control of migration in China was relaxed gradually, freeing peasants to start their own businesses and reach out to work also in urban areas. Since then the “floating population” (migrants without local hukou) took great momentum and drew great attention from both the media and academia. The scale of such internal migration is enormous –the floating population has reached to a number of 79 million in 2000, and as of 2010, the number of migrant workers from rural China amounts to over 221 million and according to the annual survey results projections by National Bureau of Statistics; the total migrant workers in china in 2012 amounted to 262.61 million, which refers to an increase of 9.83 million compared with the previous year with increase percentage by 3.9%. Using China’s Jiangxi Province as a case, this paper examines patterns of internal migration as a response of emigrations in the context of high emigration communities. Our findings suggest that emigration of individuals initially deterred both inter-provincial and intra- provincial migration of other family members, and yet, overtime they had an increasing propensity to migrate internally at both scales.

Keywords: internal migration, jiangxi, nanchang, remittances

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467 Numerical Simulation of Fracturing Behaviour of Pre-Cracked Crystalline Rock Using a Cohesive Grain-Based Distinct Element Model

Authors: Mahdi Saadat, Abbas Taheri

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Understanding the cracking response of crystalline rocks at mineralogical scale is of great importance during the design procedure of mining structures. A grain-based distinct element model (GBM) is employed to numerically study the cracking response of Barre granite at micro- and macro-scales. The GBM framework is augmented with a proposed distinct element-based cohesive model to reproduce the micro-cracking response of the inter- and intra-grain contacts. The cohesive GBM framework is implemented in PFC2D distinct element codes. The microstructural properties of Barre granite are imported in PFC2D to generate synthetic specimens. The microproperties of the model is calibrated against the laboratory uniaxial compressive and Brazilian split tensile tests. The calibrated model is then used to simulate the fracturing behaviour of pre-cracked Barre granite with different flaw configurations. The numerical results of the proposed model demonstrate a good agreement with the experimental counterparts. The GBM framework proposed thus appears promising for further investigation of the influence of grain microstructure and mineralogical properties on the cracking behaviour of crystalline rocks.

Keywords: discrete element modelling, cohesive grain-based model, crystalline rock, fracturing behavior

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466 Chemicals to Remove and Prevent Biofilm

Authors: Cynthia K. Burzell

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Aequor's Founder, a Marine and Medical Microbiologist, discovered novel, non-toxic chemicals in the ocean that uniquely remove biofilm in minutes and prevent its formation for days. These chemicals and over 70 synthesized analogs that Aequor developed can replace thousands of toxic biocides used in consumer and industrial products and, as new drug candidates, kill biofilm-forming bacteria and fungi Superbugs -the antimicrobial-resistant (AMR) pathogens for which there is no cure. Cynthia Burzell, PhD., is a Marine and Medical Microbiologist studying natural mechanisms that inhibit biofilm formation on surfaces in contact with water. In 2002, she discovered a new genus and several new species of marine microbes that produce small molecules that remove biofilm in minutes and prevent its formation for days. The molecules include new antimicrobials that can replace thousands of toxic biocides used in consumer and industrial products and can be developed into new drug candidates to kill the biofilm-forming bacteria and fungi -- including the antimicrobial-resistant (AMR) Superbugs for which there is no cure. Today, Aequor has over 70 chemicals that are divided into categories: (1) Novel natural chemicals. Lonza validated that the primary natural chemical removed biofilm in minutes and stated: "Nothing else known can do this at non-toxic doses." (2) Specialty chemicals. 25 of these structural analogs are already approved under the U.S. Environmental Protection Agency (EPA)'s Toxic Substances Control Act, certified as "green" and available for immediate sale. These have been validated for the following agro-industrial verticals: (a) Surface cleaners: The U.S. Department of Agriculture validated that low concentrations of Aequor's formulations provide deep cleaning of inert, nano and organic surfaces and materials; (b) Water treatments: NASA validated that one dose of Aequor's treatment in the International Space Station's water reuse/recycling system lasted 15 months without replenishment. DOE validated that our treatments lower energy consumption by over 10% in buildings and industrial processes. Future validations include pilot projects with the EPA to test efficacy in hospital plumbing systems. (c) Algae cultivation and yeast fermentation: The U.S. Department of Energy (DOE) validated that Aequor's treatment boosted biomass of renewable feedstocks by 40% in half the time -- increasing the profitability of biofuels and biobased co-products. DOE also validated increased yields and crop protection of algae under cultivation in open ponds. A private oil and gas company validated decontamination of oilfield water. (3) New structural analogs. These kill Gram-negative and Gram-positive bacteria and fungi alone, in combinations with each other, and in combination with low doses of existing, ineffective antibiotics (including Penicillin), "potentiating" them to kill AMR pathogens at doses too low to trigger resistance. Both the U.S. National Institutes for Health (NIH) and Department of Defense (DOD) has executed contracts with Aequor to provide the pre-clinical trials needed for these new drug candidates to enter the regulatory approval pipelines. Aequor seeks partners/licensees to commercialize its specialty chemicals and support to evaluate the optimal methods to scale-up of several new structural analogs via activity-guided fractionation and/or biosynthesis in order to initiate the NIH and DOD pre-clinical trials.

Keywords: biofilm, potentiation, prevention, removal

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465 Use of Cloud-Based Virtual Classroom in Connectivism Learning Process to Enhance Information Literacy and Self-Efficacy for Undergraduate Students

Authors: Kulachai Kultawanich, Prakob Koraneekij, Jaitip Na-Songkhla

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The way of learning has been changed into a new paradigm since the improvement of network and communication technology, so learners have to interact with massive amount of the information. Thus, information literacy has become a critical set of abilities required by every college and university in the world. Connectivism is considered to be an alternative way to design information literacy course in online learning environment, such as Virtual Classroom (VC). With the change of learning pedagogy, VC is employed to improve the social capability by integrating cloud-based technology. This paper aims to study the use of Cloud-based Virtual Classroom (CBVC) in Connectivism learning process to enhance information literacy and self-efficacy of twenty-one undergraduate students who registered in an e-publishing course at Chulalongkorn University. The data were gathered during 6 weeks of the study by using the following instruments: (1) Information literacy test (2) Information literacy rubrics (3) Information Literacy Self-Efficacy (ILSE) Scales and (4) Questionnaire. The result indicated that students have information literacy and self-efficacy posttest mean scores higher than pretest mean scores at .05 level of significant after using CBVC in Connectivism learning process. Additionally, the study identified that the Connectivism learning process proved useful for developing information rich environment and a sense of community, and the CBVC proved useful for developing social connection.

Keywords: cloud-based, virtual classroom, connectivism, information literacy

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464 Electromechanical-Traffic Model of Compression-Based Piezoelectric Energy Harvesting System

Authors: Saleh Gareh, B. C. Kok, H. H. Goh

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Piezoelectric energy harvesting has advantages over other alternative sources due to its large power density, ease of applications, and capability to be fabricated at different scales: macro, micro, and nano. This paper presents an electromechanical-traffic model for roadway compression-based piezoelectric energy harvesting system. A two-degree-of-freedom (2-DOF) electromechanical model has been developed for the piezoelectric energy harvesting unit to define its performance in power generation under a number of external excitations on road surface. Lead Zirconate Titanate (PZT-5H) is selected as the piezoelectric material to be used in this paper due to its high Piezoelectric Charge Constant (d) and Piezoelectric Voltage Constant (g) values. The main source of vibration energy that has been considered in this paper is the moving vehicle on the road. The effect of various frequencies on possible generated power caused by different vibration characteristics of moving vehicle has been studied. A single unit of circle-shape Piezoelectric Cymbal Transducer (PCT) with diameter of 32 mm and thickness of 0.3 mm be able to generate about 0.8 mW and 3 mW of electric power under 4 Hz and 20 Hz of excitation, respectively. The estimated power to be generated for multiple arrays of PCT is approximately 150 kW/ km. Thus, the developed electromechanical-traffic model has enormous potential to be used in estimating the macro scale of roadway power generation system.

Keywords: piezoelectric energy harvesting, cymbal transducer, PZT (lead zirconate titanate), 2-DOF

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463 The Relationship between General Self-Efficacy, Perfectionism and Trait Anxiety: A Study among Gifted Students

Authors: Marialena Kostouli, Georgia Tsoulfa

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The aim of this study is to investigate the relationship between general self-efficacy, perfectionism, and gifted students’ trait anxiety. One hundred fifty three students, who were all selected and enrolled at the Center for Talented Youth (CTY) - Greece summer program, participated in the study. The sample consisted of 78 males (51%) and 75 females (49%), with a mean age of 14.96 years (SD = 1.16 years). Three self-report questionnaires were used for the purposes of the current study, the Frost Multidimensional Perfectionism scale, the State-Trait anxiety inventory and the General Self-Efficacy scale. The results revealed a significant correlation between trait anxiety, general self-efficacy and the four sub-scales of perfectionism (concern over mistakes and doubts about actions, excessive concern with parents’ expectations and evaluation, excessively high personal standards and concern with precision, order, and organization). It was also found that the female CTY students experience greater levels of trait anxiety compared to the male CTYers. Moreover, a multiple regression analysis was conducted in order to determine the possible predictors of gifted students’ trait anxiety. The analysis showed that general self-efficacy and the concern over mistakes and doubts about actions significantly predicted the trait anxiety of the gifted children that we examined. Avenues of further research and implications for the development of interventions to help gifted students promote their general self-efficacy, reduce their concern over their actions and develop strategies in order to cope with their anxiety are discussed.

Keywords: general self-efficacy, gifted students, perfectionism, trait anxiety

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462 Predictors of Childhood Trauma and Dissociation in University Students

Authors: Erdinc Ozturk, Gizem Akcan

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The aim of this study was to determine some psychosocial variables that predict childhood trauma and dissociation in university students. These psychosocial variables were perceived social support, relationship status, gender and life satisfaction. 250 (125 males, 125 females) university students (bachelor, master and postgraduate degree) were enrolled in this study. They were chosen from universities in Istanbul at the education year of 2016-2017. Dissociative Experiences Scale (DES), Childhood Trauma Questionnaire (CTQ), Multidimensional Perceived Social Support Scale, Life Satisfaction Scale and Relationship Scales Questionnaire were used to assess related variables. Demographic information form was given to students in order to have their demographic information. Frequency distribution, multiple linear regression, and t-test analysis were used for statistical analysis. As together, perceived social support, relationship status and life satisfaction were found to have predictive value on trauma among university students. However, as together, these psychosocial variables did not have predictive value on dissociation. Only, trauma and relationship status had significant predictive value on dissociation. Moreover, there was significant difference between males and females in terms of trauma; however, dissociation scores of participants were not significantly different in terms of gender.

Keywords: childhood trauma, dissociation, perceived social support, relationship status, life satisfaction

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461 Impact of Organizational Culture and Strategic Leadership on Organizational Resilience

Authors: Anyia Nduka, Aslan Bin Amad Senin

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Organizational culture, strategic leadership and organizational resilience have gained significant attention in recent years. This study aims to examine the relationship between these factors and their combined influence on an organization's ability to adapt and thrive in the face of challenges and disruptions. A mixed-methods approach, combining quantitative survey data and qualitative interviews with leaders and employees from cohort organizations within the industry. The quantitative phase involves measuring organizational culture, strategic leadership behaviours, and organizational resilience using standardized scales. This study highlighted the significance of organizational culture and strategic leadership in building and sustaining organizational resilience. Preliminary findings suggest a strong positive relationship between a resilient organizational culture and strategic leadership practices. Secondly, Organizations can enhance their capacity to respond to disruptions, exploit opportunities, and achieve long-term success in a rapidly changing business environment. Furthermore, the qualitative analysis reveals several key themes that elucidate the link between organizational culture, strategic leadership, and resilience. This study contributes to the growing body of knowledge on organizational resilience and strategic leadership, providing insights and practical implications for leaders and practitioners seeking to strengthen their organizations' resilience capabilities. Further research is needed to explore the specific mechanisms and contextual factors that influence the relationship between these variables in different organizational contexts and industries.

Keywords: organizational culture, strategic leadership, organizational resilience, leadership

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460 Analytical and Numerical Investigation of Friction-Restricted Growth and Buckling of Elastic Fibers

Authors: Peter L. Varkonyi, Andras A. Sipos

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The quasi-static growth of elastic fibers is studied in the presence of distributed contact with an immobile surface, subject to isotropic dry or viscous friction. Unlike classical problems of elastic stability modelled by autonomous dynamical systems with multiple time scales (slowly varying bifurcation parameter, and fast system dynamics), this problem can only be formulated as a non-autonomous system without time scale separation. It is found that the fibers initially converge to a trivial, straight configuration, which is later replaced by divergence reminiscent of buckling phenomena. In order to capture the loss of stability, a new definition of exponential stability against infinitesimal perturbations for systems defined over finite time intervals is developed. A semi-analytical method for the determination of the critical length based on eigenvalue analysis is proposed. The post-critical behavior of the fibers is studied numerically by using variational methods. The emerging post-critical shapes and the asymptotic behavior as length goes to infinity are identified for simple spatial distributions of growth. Comparison with physical experiments indicates reasonable accuracy of the theoretical model. Some applications from modeling plant root growth to the design of soft manipulators in robotics are briefly discussed.

Keywords: buckling, elastica, friction, growth

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459 Multi-Scale Green Infrastructure: An Integrated Literature Review

Authors: Panpan Feng

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The concept of green infrastructure originated in Europe and the United States. It aims to ensure smart growth of urban and rural ecosystems and achieve sustainable urban and rural ecological, social, and economic development by combining it with gray infrastructure in traditional planning. Based on the literature review of the theoretical origin, value connotation, and measurement methods of green infrastructure, this study summarizes the research content of green infrastructure at different scales from the three spatial levels of region, city, and block and divides it into functional dimensions, spatial dimension, and strategic dimension. The results show that in the functional dimension, from region-city-block, the research on green infrastructure gradually shifts from ecological function to social function. In the spatial dimension, from region-city-block, the research on the spatial form of green infrastructure has shifted from two-dimensional to three-dimensional, and the spatial structure of green infrastructure has shifted from single ecological elements to multiple composite elements. From a strategic perspective, green infrastructure research is more of a spatial planning tool based on land management, environmental livability and ecological psychology, providing certain decision-making support.

Keywords: green infrastructure, multi-scale, social and ecological functions, spatial strategic decision-making tools

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458 Experimental Study on the Variation of Young's Modulus of Hollow Clay Brick Obtained from Static and Dynamic Tests

Authors: M. Aboudalle, Le Btth, M. Sari, F. Meftah

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In parallel with the appearance of new materials, brick masonry had and still has an essential part of the construction market today, with new technical challenges in designing bricks to meet additional requirements. Being used in structural applications, predicting the performance of clay brick masonry allows a significant cost reduction, in terms of practical experimentation. The behavior of masonry walls depends on the behavior of their elementary components, such as bricks, joints, and coatings. Therefore, it is necessary to consider it at different scales (from the scale of the intrinsic material to the real scale of the wall) and then to develop appropriate models, using numerical simulations. The work presented in this paper focuses on the mechanical characterization of the terracotta material at ambient temperature. As a result, the static Young’s modulus obtained from the flexural test shows different values in comparison with the compression test, as well as with the dynamic Young’s modulus obtained from the Impulse excitation of vibration test. Moreover, the Young's modulus varies according to the direction in which samples are extracted, where the values in the extrusion direction diverge from the ones in the orthogonal directions. Based on these results, hollow bricks can be considered as transversely isotropic bimodulus material.

Keywords: bimodulus material, hollow clay brick, ımpulse excitation of vibration, transversely isotropic material, young’s modulus

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457 Fault Tolerant Control System Using a Multiple Time Scale SMC Technique and a Geometric Approach

Authors: Ghodbane Azeddine, Saad Maarouf, Boland Jean-Francois, Thibeault Claude

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This paper proposes a new design of an active fault-tolerant flight control system against abrupt actuator faults. This overall system combines a multiple time scale sliding mode controller for fault compensation and a geometric approach for fault detection and diagnosis. The proposed control system is able to accommodate several kinds of partial and total actuator failures, by using available healthy redundancy actuators. The overall system first estimates the correct fault information using the geometric approach. Then, and based on that, a new reconfigurable control law is designed based on the multiple time scale sliding mode technique for on-line compensating the effect of such faults. This approach takes advantages of the fact that there are significant difference between the time scales of aircraft states that have a slow dynamics and those that have a fast dynamics. The closed-loop stability of the overall system is proved using Lyapunov technique. A case study of the non-linear model of the F16 fighter, subject to the rudder total loss of control confirms the effectiveness of the proposed approach.

Keywords: actuator faults, fault detection and diagnosis, fault tolerant flight control, sliding mode control, multiple time scale approximation, geometric approach for fault reconstruction, lyapunov stability

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456 Conceptual Model of a Residential Waste Collection System Using ARENA Software

Authors: Bruce G. Wilson

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The collection of municipal solid waste at the curbside is a complex operation that is repeated daily under varying circumstances around the world. There have been several attempts to develop Monte Carlo simulation models of the waste collection process dating back almost 50 years. Despite this long history, the use of simulation modeling as a planning or optimization tool for waste collection is still extremely limited in practice. Historically, simulation modeling of waste collection systems has been hampered by the limitations of computer hardware and software and by the availability of representative input data. This paper outlines the development of a Monte Carlo simulation model that overcomes many of the limitations contained in previous models. The model uses a general purpose simulation software program that is easily capable of modeling an entire waste collection network. The model treats the stops on a waste collection route as a queue of work to be processed by a collection vehicle (or server). Input data can be collected from a variety of sources including municipal geographic information systems, global positioning system recorders on collection vehicles, and weigh scales at transfer stations or treatment facilities. The result is a flexible model that is sufficiently robust that it can model the collection activities in a large municipality, while providing the flexibility to adapt to changing conditions on the collection route.

Keywords: modeling, queues, residential waste collection, Monte Carlo simulation

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455 Examining the Influence of Question Phrasing in Police Interviews on Suspects’ Inferences Regarding Interviewer’s Prior Knowledge

Authors: Meghana Srivatsav, Timothy J. Luke, Par Anders Granhag, Aldert Vrij

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The aim of this study was to understand how the phrasing of questions influences guilty suspects’ inferences regarding prior information held by the interviewer about the suspect’s crime-related activities. Three phrasing factors were explored namely specificity (crime-related details within questions), stressor (emphasis on the importance of the information in the question) and phase presentation (whether a specific activity was questioned about). 370 participants were recruited and randomly assigned into 6 different question-phrasing groups. Participants assumed the role of a suspect, read a crime narrative and an interview transcript based on the suspect’s activities. Participants responded to scales that measured their perception of interviewer’s knowledge (PIK) based on the questions posed by the interviewer in the interview transcripts. The researchers found that there is an effect of specific details revealed in the questions on the suspect’s perception of interviewer knowledge. Questioning about a specific activity also increased their perception of interviewer’s prior knowledge. However, the individual hypotheses were only partially supported. The study allowed the researchers to explore a psycholinguistic approach to investigate the underlying mechanisms of inferences drawn by suspects from the phrasing of investigative questions.

Keywords: police interviewing, question framing effects on suspects, suspect inferences from questions, suspect interviews

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454 Quantitative Analysis of the Functional Characteristics of Urban Complexes Based on Station-City Integration: Fifteen Case Studies of European, North American, and East Asian Railway Stations

Authors: Dai Yizheng, Chen-Yang Zhang

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As station-city integration has been widely accepted as a strategy for mixed-use development, a quantitative analysis of the functional characteristics of urban complexes based on station-city integration is urgently needed. Taking 15 railway stations in European, North American, and East Asian cities as the research objects, this study analyzes their functional proportion, functional positioning, and functional correlation with respect to four categories of functional facilities for both railway passenger flow and subway passenger flow. We found that (1) the functional proportion of urban complexes was mainly concentrated in three models: complementary, dominant, and equilibrium. (2) The mathematical model affected by the functional proportion was created to evaluate the functional positioning of an urban complex at three scales: station area, city, and region. (3) The strength of the correlation between the functional area and passenger flow was revealed via data analysis using Pearson’s correlation coefficient. Finally, the findings of this study provide a valuable reference for research on similar topics in other countries that are developing station-city integration.

Keywords: urban complex, station-city integration, mixed-use, function, quantitative analysis

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453 Patient Reported Outcome Measures Post Implant Based Reconstruction Basildon Hospital

Authors: Danny Fraser, James Zhang

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Aim of the study: Our study aims to identify any statistically significant evidence as it relates to PROMs for mastectomy and implant-based reconstruction to guide future surgical management. Method: The demographic, pre and post-operative treatment and implant characteristics were collected of all patients at Basildon hospital who underwent breast reconstruction from 2017-2023. We used the Breast-Q psychosocial well-being, physical well-being, and satisfaction with breasts scales. An Independent t-test was conducted for each group, and linear regression of age and implant size. Results: 69 patients were contacted, and 39 PROMs returned. The mean age of patients was 57.6. 40% had smoked before, and 40.8% had BMI>30. 29 had pre-pectoral placement, and 40 had subpectoral placement. 17 had smooth implants, and 52 textured. Sub pectoral placement was associated with higher (75.7 vs. 61.9 p=0.046) psychosocial scores than pre pectoral, and textured implants were associated with a lower physical score than the smooth surface (34.7 VS 50.2 P=0.046). On linear regression, age was positively associated (p=0.007) with psychosocial score. Conclusion: We present a large cohort of patients who underwent breast reconstruction. Understanding the PROMs of these procedures can guide clinicians, patients and policy makers to be more informed of the course of rehabilitation of these operations. Significance: We have found that from a patient perspective subpectoral implant placement was associated with a statistically significant improvement in psychosocial scores.

Keywords: breast surgery, mastectomy, breast implants, oncology

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452 Climate Adaptability of Vernacular Courtyards in Jiangnan Area, Southeast China

Authors: Yu Bingqing

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Courtyards with suitable scale can effectively modify the microclimate and improve thermal comfort. To comprehend the thermal environment of courtyards with different scales in various areas of Jiangnan, this study conducts field research in three traditional villages: (1) Chunman-ting House in Guanlu Village, Huangshan City, Anhui Province, (2) Heqin-tang House in Lizhai Village, Xianju County, Taizhou City, Zhejiang Province, and (3) Langai-Qirui House in Baima-zhai Village, Fengcheng City, Jiangxi Province. First, based on the collected data, the article analyzes the relationship between the thermal environment and the depth-to-height ratio of the courtyard. Second, it employs the Envi-met software to perform numerical simulations, analyzing thermal comfort in various courtyards with different depth-to-height ratios. Finally, it uses the simulation results to deduce the courtyard models suitable for hot summers and cold winters in the Jiangnan area. The result of this study can improve the thermal comfort of vernacular courtyards in the Jiangnan area by adopting a suitable scale for future protection and regeneration. The transformation and utilization of the climate-responsive courtyard model can also become a reference for modern architectural design.

Keywords: vernacular courtyards, thermal environment, depth-to-height ratio, climate adaptability,Southeast China

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451 Gender Differences in Adolescent Avatars: Gender Consistency and Masculinity-Femininity of Nicknames and Characters

Authors: Monika Paleczna, Małgorzata Holda

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Choosing an avatar's gender in a computer game is one of the key elements in the process of creating an online identity. The selection of a male or female avatar can define the entirety of subsequent decisions regarding both appearance and behavior. However, when the most popular games available for the Nintendo console in 1998 were analyzed, it turned out that 41% of computer games did not have female characters. Nowadays, players create their avatars based mainly on binary gender classification, with male and female characters to choose from. The main aim of the poster is to explore gender differences in adolescent avatars. 130 adolescents aged 15-17 participated in the study. They created their avatars and then played a computer game. The creation of the avatar was based on the choice of gender, then physical and mental characteristics. Data on gender consistency (consistency between participant’s sex and gender selected for the avatar) and masculinity-femininity of avatar nicknames and appearance will be presented. The masculinity-femininity of avatar nicknames and appearance was assessed by expert raters on a very masculine to very feminine scale. Additionally, data on the relationships of the perceived levels of masculinity-femininity with hostility-friendliness and the intelligence of avatars will be shown. The dimensions of hostility-friendliness and intelligence were also assessed by expert raters on scales ranging from very hostile to very friendly and from very low intelligence to very high intelligence.

Keywords: gender, avatar, adolescence, computer games

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450 Socioeconomic Status and Use of Web-Based Information Resources by Public Polytechnic Students in Southwestern Nigeria

Authors: John Adeboye Oyeboade, Pius Olatunji Olaojo, Kuburay Folashade Yusuf, John Oluwaseye Adebayo

Abstract:

Web-based Information Resources (WBIR) are increasingly becoming essential tools for students to accomplish academic tasks. Preliminary observation revealed that many polytechnic libraries in Southwestern Nigeria do not subscribe or renew subscriptions to WBIR academic databases, and students use free-based electronic resources. Hence, this study was carried out to investigate socioeconomic status and use of WBIR by public polytechnic students in Southwestern Nigeria. Six public polytechnics out of the 16 offerings of Higher National Diploma (HND) programs were selected by stratified random sampling to reflect federal and state polytechnics. A proportionate size sampling technique was used to select 1,463 HND students. The instruments used were Socioeconomic status (SeS) (α=0.81) and WBIR used for Academic Tasks (α=0.98) scales. Data were analyzed using descriptive statistics and Pearson’s product-moment correlation at a 0.05 level of significance. Students’ SeS ( =79.10) was moderate. Online reference sources ( =3.97), Web 2.0 ( =3.50), and social media ( =3.00) were regularly used WBIR. WBIR use ( =53.34) was moderate. The students used WBIR for project writing ( =3.46) and class assignments ( =3.42). The Students’ SeS (r=0.59) had significant relationships with WBIR use. Socioeconomic status directly influenced the use of WBIR for academic tasks. Management of polytechnics should provide WBIR subscriptions for students’ use in the polytechnic e-libraries.

Keywords: public polytechnic students, polytechnic libraries, socioeconomic status, Web-based information resources

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449 Making New Theoretical Insights into Violence: The Temporal and Spatial Relevance of Blood Spatter Crime Scene Investigations

Authors: Simone Jane Dennis

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This paper leverages the spatial and temporal investigative strategy utilized by crime scene investigators – blood spatter work– to engage with the real and metaphorical memorialization of blood-soaked places. It uses this key trope with phenomenological sensibility, to trace the physical and temporal movement of blood outbound from the human body to sites beyond. Working backward, as crime scene investigators do, this paper traces the importance of both space and time and their confluence, to developing a comprehensive theory of violence. To do this work, the paper engages a range of geo-violent scales, from murder scenes to genocides, to both engage an extraordinarily replete literature of bloodshed across history and to move beyond analyses of how significance is assigned to the sites in which blood comes to rest to instead consider the importance of space and time to the structure of violence itself. It is in this regard that the kind of investigative work upon which blood spatter analysis depends is crucial: it engages time and space in reverse to understand the microscopic relations between bodies, places, and numerous (biological, clock, and seasonal) temporalities. Considering the circumstances under which blood escaped a body, the details of its destination in place, and the temporal circumstances of corporal departure, is crucial to making new knowledge about the peculiar temporality and spatiality of violence itself.

Keywords: blood, crime scenes, temporality, violence

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448 Mixotrophic Cultivation of Microalgae as a Feasible Strategy for Carotenoid Production

Authors: Jian Li

Abstract:

Carotenoids area group of metabolites in mostly photosynthetic organisms such as plants and microalgae and have wide applications in cosmetics, food, feed, and health industries. Although phototrophic cultivation of microalgae has been developed to produce some carotenoids for decades, most carotenoids are currently synthesized chemically at industrial scales because of affordable production costs. Chemical carotenoids are regarded not as safe for human beings as natural carotenoids and are restricted only for animal feed markets, and the industries call for inexpensive sources of natural products. Microalgae grow much quicker in mixotrophy than in phototrophy, and thus mixotrophic cultivation processes have great potential to reduce the production cost of carotenoids from microalgae. However, much more expensive photobioreactor systems and more strictly controlled sterile processes are needed to avoid contamination by heterotrophic organisms during mixotrophic cultivation processes, which makes mixotrophy, in fact, much more expensive than phototrophic cultivation. Recently technical breakthroughs have been reported to overcome contamination problems in photobioreactor systems traditionally used for phototrophic cultivation, and a much lower process cost of mixotrophic cultivation than that of phototrophic cultivation might be achieved for carotenoid production. These reviews intend to summarize recent technical advancements in mixotrophic cultivation of microalgae, to evaluate the economic viability of carotenoid production from mixotrophically cultivated microalgae, and to prospect mixotrophy as a strategy to produce a variety of carotenoids for industrial applications.

Keywords: microalgae, carotenoid, mixotrophy, biotechnology

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447 Nurses' Knowledge and Attitudes toward the Use of Physical Restraints

Authors: Fatema Salman, Ridha Hammam, Fatima Khairallah, Fatima Aradi, Nafeesa Abdulla, Mohammed Alsafar

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Purpose: This study aims at measuring the extent of nurses’ knowledge and attitudes toward the use of physical restraints in different hospital wards at Salmaniya Medical Complex (SMC). Background: The habitual use of physical restraint is a widespread practice among nurses working in the clinical settings. Restraints inflict many deleterious consequences on patients physically and psychologically which in turn increases their morbidity and mortality risk and jeopardizes care quality. Nurses’ knowledge and attitudes toward physical restraints are crucial determinants of the persistence of this practice. Literature review: the evidence of lack of knowledge among nurses regarding the use of physical restraints is overwhelming in various clinical settings, especially in two main areas which are the negative consequences and the available alternatives to physical restraints. Studies explored nurses’ attitudes toward physical restraints yielded inconsistent findings. Equally comparable, some studies found that nurses hold positive attitudes toward the use of physical restraints while some others reported just the opposite. Methods: Self-administered knowledge and attitudes scales to 106 nurses working in the SMC. Findings: nurses hold the moderate level of knowledge about restraints (M=58%) with weak negative attitudes (M = -20%) toward using it. Significant moderately-strong negative correlation (r= -0.57, r2= 0.32, p= 0.000) was uncovered between nurses knowledge and their attitudes which provided an empirical explanation of this phenomenon (use of physical restraints). Recommendations: Induction of awareness program that especially focuses on the negative consequences and encourages the use of alternatives is an evident need. This effort necessarily should be adjoined with policy and procedure adjustments.

Keywords: attitudes, knowledge, nurses, restraints

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446 Mechanical Characterization of Porcine Skin with the Finite Element Method Based Inverse Optimization Approach

Authors: Djamel Remache, Serge Dos Santos, Michael Cliez, Michel Gratton, Patrick Chabrand, Jean-Marie Rossi, Jean-Louis Milan

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Skin tissue is an inhomogeneous and anisotropic material. Uniaxial tensile testing is one of the primary testing techniques for the mechanical characterization of skin at large scales. In order to predict the mechanical behavior of materials, the direct or inverse analytical approaches are often used. However, in case of an inhomogeneous and anisotropic material as skin tissue, analytical approaches are not able to provide solutions. The numerical simulation is thus necessary. In this work, the uniaxial tensile test and the FEM (finite element method) based inverse method were used to identify the anisotropic mechanical properties of porcine skin tissue. The uniaxial tensile experiments were performed using Instron 8800 tensile machine®. The uniaxial tensile test was simulated with FEM, and then the inverse optimization approach (or the inverse calibration) was used for the identification of mechanical properties of the samples. Experimentally results were compared to finite element solutions. The results showed that the finite element model predictions of the mechanical behavior of the tested skin samples were well correlated with experimental results.

Keywords: mechanical skin tissue behavior, uniaxial tensile test, finite element analysis, inverse optimization approach

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445 Stressful Events and Serious Mood Disorders

Authors: Horesh Reinman Netta

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Objectives: To examine the relationship between stressful life events and recurrent major depressive disorders Methods: Three groups of 50 subjects were assessed. One group had a recurrent major depressive disorder with melancholic features; the second group met the criteria for borderline personality disorder, and the third consisted of healthy controls. The Structured Clinical Interview for AXIS I DSM-IV Disorders sand the Structured Clinical Interview for AXIS II DSM-IV Disorders were used for diagnosis. The Israel Psychiatric Epidemiology Research Interview (IPERI) Life Event Scale and the Coddington Life Events Schedule (CLES) were used to measure life events which were confirmed with a confirmatory semi-structured interview. The Beck Depression Inventory and the Satisfaction from Life scales were also administered. Results : The total number of loss-related events in childhood and in the year preceding the first episode was significantly higher in the affective disorder group than in the two control groups. Total number of LE, uncontrolled and independent events were also more common in the depressed patients in the year preceding the first episode. No category of SLE was differentiated among any of the three groups during any period of time following the first depressive episode. Conclusions: SLE play an important role in the onset of affective disorders. There appear to be specific kinds of SLE occurring in childhood and in the year preceding a first episode that have particular significance. SLE may have a lesser role in the maintenance of this illness.

Keywords: modd dosorders, recurrent depression, stress, life events

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444 Comprehensive Evaluation of COVID-19 Through Chest Images

Authors: Parisa Mansour

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The coronavirus disease 2019 (COVID-19) was discovered and rapidly spread to various countries around the world since the end of 2019. Computed tomography (CT) images have been used as an important alternative to the time-consuming RT. PCR test. However, manual segmentation of CT images alone is a major challenge as the number of suspected cases increases. Thus, accurate and automatic segmentation of COVID-19 infections is urgently needed. Because the imaging features of the COVID-19 infection are different and similar to the background, existing medical image segmentation methods cannot achieve satisfactory performance. In this work, we try to build a deep convolutional neural network adapted for the segmentation of chest CT images with COVID-19 infections. First, we maintain a large and novel chest CT image database containing 165,667 annotated chest CT images from 861 patients with confirmed COVID-19. Inspired by the observation that the boundary of an infected lung can be improved by global intensity adjustment, we introduce a feature variable block into the proposed deep CNN, which adjusts the global features of features to segment the COVID-19 infection. The proposed PV array can effectively and adaptively improve the performance of functions in different cases. We combine features of different scales by proposing a progressive atrocious space pyramid fusion scheme to deal with advanced infection regions with various aspects and shapes. We conducted experiments on data collected in China and Germany and showed that the proposed deep CNN can effectively produce impressive performance.

Keywords: chest, COVID-19, chest Image, coronavirus, CT image, chest CT

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