Search results for: external aerodynamics

Authors: Muteeb Ulhaq, Rizwan Latif, Sayed Adnan Qasim, Imran Shafi

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Diesel engines are most efficient and reliable in terms of efficiency, reliability and adaptability. Most of the research and development up till now have been directed towards High-Speed Diesel Engine, for Commercial use. In these engines objective is to optimize maximum acceleration by reducing exhaust emission to meet international standards. In high torque low-speed engines the requirement is altogether different. These types of Engines are mostly used in Maritime Industry, Agriculture industry, Static Engines Compressors Engines etc. Unfortunately due to lack of research and development, these engines have low efficiency and high soot emissions and one of the most effective way to overcome these issues is by efficient combustion in an engine cylinder, the fuel spray atomization process plays a vital role in defining mixture formation, fuel consumption, combustion efficiency and soot emissions. Therefore, a comprehensive understanding of the fuel spray characteristics and atomization process is of a great importance. In this research, we will examine the effects of primary breakup modeling on the spray characteristics under diesel engine conditions. KH-ACT model is applied to cater the effect of aerodynamics in an engine cylinder and also cavitations and turbulence generated inside the injector. It is a modified form of most commonly used KH model, which considers only the aerodynamically induced breakup based on the Kelvin–Helmholtz instability. Our model is extensively evaluated by performing 3-D time-dependent simulations on Open FOAM, which is an open source flow solver. Spray characteristics like Spray Penetration, Liquid length, Spray cone angle and Souter mean diameter (SMD) were validated by comparing the results of Open Foam and Matlab. Including the effects of cavitation and turbulence enhances primary breakup, leading to smaller droplet sizes, decrease in liquid penetration, and increase in the radial dispersion of spray. All these properties favor early evaporation of fuel which enhances Engine efficiency.

Keywords: Kelvin–Helmholtz instability, open foam, primary breakup, souter mean diameter, turbulence

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Authors: Ayman Haddad, Wafaa Sbeiti, Amr Qasem

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The main aim of this paper is to provide an overview of the most influential economic changes and accounting legislation affecting financial reporting and disclosure practices in Jordan. It also provides an overview of disclosure studies conducted in Jordan covering the year(s) between 1986 and 2014. The economic changes in Jordan required conducting economic reform and revising/issuing new regulations and financial market reforms that led to an improvement in disclosure practices. The issuance of Temporary Securities Law and its Directives of Disclosure in 1997, which came into effect in 1998, is considered as the turning point in the improvement of disclosure practice in Jordan. Based on a review of prior disclosure studies, we conclude that disclosure practices have improved overtime. We also observe that that firm size as a factor has always affected the level of disclosure in Jordan and followed by external auditing while liquidity was found to have the least effect. The paper also addresses the disclosure items required in Corporate Governance Codes that exist for listed shareholding companies, banks, and insurance companies. Finally, the paper discusses the quality of accounting education in Jordan since prior studies noted its impact on accounting practice.

Keywords: accounting legislation, corporate governance, disclosure practice, Jordan

Procedia PDF Downloads 361

Authors: Farzana Sharmin, Mohammad Tipu Sultan, Benqian Li

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Advancement of new media technology and consumption of social media have altered the way of communication in the tourism industry, mostly for consumers’ travel planning, online purchase, and experience sharing activity. There is an accelerating trend among young consumers’ to utilize this new media technology. This paper aims to analyze the attitude of young consumers’ about social media use for travel purposes. The convenience random sample method used to collect data from an urban area of Shanghai (China), consists of 225 young consumers’. This survey identified behavioral determinants of social media consumption by the extended theory of planned behavior (TPB). The instrument developed support on previous research to test hypotheses. The results of structural analyses indicate that attitude towards the use of social media is affected by external factors such as availability and accessibility of technology. In addition, subjective norm and perceived behavioral control have partially influenced the attitude of respondents’. The results of this study could help to improve social media travel marketing and promotional strategies for respective groups.

Keywords: social media, theory of planned behavior, travel behavior, young consumer

Procedia PDF Downloads 196

Authors: Zal U’yun Wan Mahmood, Norfaizal Mohamed, Nita Salina Abu Bakar, Yii Mei Wo, Abdul Kadir Ishak, Mohamad Noh Sawon, Mohd Tarmizi Ishak, Khairul Nizam Razali

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The study of thorium radiotracer bioaccumulation in the whole body tropical freshwater fish (Anabas testudeneus; climb pearch) was performed. The objective of this study was to evaluate the effect of different Th-232 activity concentration andradiological dose in Anabas testudeneus under the laboratory bioaccumulation condition. Anabas testudeneus adults were exposed to different waterborne Th-232 levels: 0 BqL-1 (control), 50 BqL-1, 100 BqL-1,150 BqL-1and 200 BqL-1for 30 days. Radionuclide concentration ratios between the whole body levels and water levels were calculated and; total dose rates and risk quotients using ERICA Assessment Tool were also estimated. The results showed the increase of waterborne Th-232 concentration corresponded to a progressive decrease of Th concentration ratio. Meanwhile, the total dose rate (internal and external) in the whole body of Anabas testudeneus less than the ERICA dose rate screening value of 10 µGyh-1 and the risk quotient less than one. Thus, the findings can be concluded that the radiological dose of Th-232 to Anabas testudeneus is a very low probability and the situation may be considered to be of negligible radiological concern.

Keywords: Anabas testudeneus, bioaccumulation, radiological dose, Th-232

Procedia PDF Downloads 325

Authors: Ilham Ihoume, Rachid Tadili, Nora Arbaoui

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Recent innovations in economical heating systems have significantly boosted ‎agricultural production by effectively managing temperature drops in greenhouse ‎microclimates. These advancements enhance product profitability in terms of quality, ‎quantity, and growth duration. This study experimentally investigates the impact of a ‎solar heating system on the microclimate of an agricultural greenhouse, focusing on ‎zucchini (Cucurbita pepo). The System comprises a copper tube placed between double ‎roof glazing and a sensible heat storage system, converting solar energy during the day ‎and storing it for night-time release. A second control greenhouse without heating ‎allows for comparative analysis at various growth stages. During the cold season, the ‎experimental greenhouse showed a temperature increase of 3°C compared to the ‎control greenhouse and 5°C above external ambient air. The relative humidity in the ‎experimental greenhouse ranged from 69% to 70%, whereas the control greenhouse recorded 68% to 86%, and ambient air ‎was between 94% to 99%. The heating systems achieved an efficiency of 73%, and ‎zucchini plants in the experimental greenhouse developed fruit 13 days earlier than ‎those in the control greenhouse.‎

Keywords: solar energy, storage, energy managment, heating system

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Authors: Getachew Demeissie Ayalew, Yongtao Sun, Yang Yang

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The spiral welded pipe manufacturing industry requires strict production standards for automated grinders for welding seams. However, traditional grinding machines in this sector are insufficient due to a lack of quality control protocols and inconsistent performance. This research aims to improve the quality of spiral welded pipes by developing intelligent automated abrasive belt grinding equipment. The system has equipped with six degrees of freedom (6 DOF) KUKA KR360 industrial robots, enabling concurrent grinding operations on both internal and external welds. The grinding robot control system is designed with a PLC, and a human-machine interface (HMI) system is employed for operations. The system includes an electric speed controller, data connection card, DC driver, analog amplifier, and HMI for input data. This control system enables the grinding of spiral welded pipe. It ensures consistent production quality and cost-effectiveness by reducing the product life cycle and minimizing risks in the working environment.

Keywords: Intelligent Systems, Spiral Welded Pipe, Grinding, Industrial Robot, End-Effector, PLC Controller System, 3D Laser Sensor, HMI.

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Authors: F. S. Alavi

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In this study, MATLAB engineering software was used in order to model an industrial Ambient Air Vaporizer (AAV), considering combined convection and conduction heat transfers from the fins and the tube. The developed theoretical model was then used to investigate the effects of various design factors such as gas flow rate, ambient air temperature, fin thickness and etc. on total vaporizer ‘s length required. Cryogenic liquid nitrogen was selected as an input fluid, in all cases. According to the results, increasing the inlet fluid flow rate has direct linear effect on the total required length of vaporizer. Vaporizer’s required length decreases by increasing the size of fin radius or size of fin thickness. The dependency of vaporizer’s length on fin thickness’ size reduces at higher values of thickness and gradually converge to zero. For low flow rates, internal convection heat transfer coefficient depends directly on gas flow rate but it becomes constant, independent on flow rate after a specific value. As the ambient air temperature increases, the external heat transfer coefficient also increases and the total required length of vaporizer decreases.

Keywords: heat exchanger, modeling, heat transfer, design

Procedia PDF Downloads 115

Authors: Samuel Onyekachi Chidi

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Nigeria today faces more internal threats stemming from ethnic and religious conflicts than external sources. This article seeks to examine the ethno-religious conflicts in Nigeria from 2015 to 2021 and their impact on national security. The research was guided by six objectives. The theoretical framework adopted for this study is Structural Conflict Theory, which provides an adequate explanation, a predictive rationale for the frequent occurrence of ethno-religious conflicts and a tendency to provide the necessary insight for their resolution. The results of the study revealed that there is a strong relationship between ethnicity, religion, conflict and national security and that the ethno-religious conflicts experienced in Nigeria have gross implications for national security. The study recommends that the secularity of the Nigerian state be restored and preserved and that the state of origin be removed and replaced by the state of residence in all our national documents, as this will reduce ethnic identity, which is in opposition to nationalism. Religious leaders, traditional rulers, the media and other stakeholders should support the government in its fight to reduce ethno-religious conflict by sensitizing its youth, preaching unity and peaceful coexistence, and discouraging the use of violence as a means of settling disputes between groups and individuals.

Keywords: ethnicity, religion, conflict, national security

Procedia PDF Downloads 76

Authors: Bartosz Olszanski, Zbigniew Nosal, Jacek Rokicki

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An experimental study of cold-jet (nitrogen) reaction control jet system has been carried out to investigate the flow control efficiency for low to moderate jet pressure ratios (total jet pressure p0jet over free stream static pressure in the wind tunnel p∞) and different angles of attack for infinite Mach number equal to 2. An investigation of jet influence was conducted on a flat plate geometry placed in the test section of intermittent supersonic wind tunnel of Department of Aerodynamics, WUT. Various convergent jet nozzle geometries to obtain different jet momentum ratios were tested on the same test model geometry. Surface static pressure measurements, Schlieren flow visualizations (using continuous and photoflash light source), load cell measurements gave insight into the supersonic crossflow interaction for different jet pressure and jet momentum ratios and their influence on the efficiency of side jet control as described by the amplification factor (actual to theoretical net force generated by the control nozzle). Moreover, the quasi-steady numerical simulations of flow through the same wind tunnel geometry (convergent-divergent nozzle plus test section) were performed using ANSYS Fluent basing on Reynolds-Averaged Navier-Stokes (RANS) solver incorporated with k-ω Shear Stress Transport (SST) turbulence model to assess the possible spurious influence of test section walls over the jet exit near field area of interest. The strong bow shock, barrel shock, and Mach disk as well as lambda separation region in front of nozzle were observed as images taken by high-speed camera examine the interaction of the jet and the free stream. In addition, the development of large-scale vortex structures (counter-rotating vortex pair) was detected. The history of complex static pressure pattern on the plate was recorded and compared to the force measurement data as well as numerical simulation data. The analysis of the obtained results, especially in the wake of the jet showed important features of the interaction mechanisms between the lateral jet and the flow field.

Keywords: flow visualization techniques, pressure measurements, reaction control jet, supersonic cross flow

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Authors: Hilda Kundai Chikwanda, Lawrence Thabo Mokhadi

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The study aimed to review the factors that lead the freight railway suppliers base in South Africa (SA) to apply the Lean and Six Sigma (L&SS) methodologies. A thorough review of the factors that lead organisations, in the different industries, to implement these methodologies was done. L&SS applications were found to be prominent in the automotive industry. In particular, the railway industry in SA and the region were reviewed in terms of challenges in capturing the freight logistics market and growing market share. Qualitative methods have been used to collect primary data and descriptive statistics was used to calculate, describe, and summarize collected research data. The results show that external factors have a greater influence on the implementation of L&SS. The study drew inferences between freight railway supplier base and the application of Lean and Six Sigma (L&SS) methodologies in the SA context. It identified challenges that leads the SA freight railway to lose market share to road freight users. It further observes and recommends that L&SS methodologies are the ideal strategy required to implement a turnaround in the trajectory of freight railways as a competitive freight transport solution.

Keywords: production, methodology, manufacturing, lean, six sigma

Procedia PDF Downloads 45

Authors: Aniruddha Kulkarni

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In very few cases of external hernias we require imaging modalities as on most occasions clinical examination tests are good enough. Ultrasound will help in chronic abdominal or groin pain, equivocal clinical results & complicated hernias. Ultrasound is useful in assessment of cause of raised intrabdominal pressure. In certain cases will comment about etiology, complications and chronicicty of lesion. Screening of rest of abdominal organs too is important advantage being real time modality. Cost effectiveness, no radiation allows modality be used repeatedly in indicated cases. Sonography is better accepted by patients too as it is cost effective. Best advanced tissue harmonic equipment and increasing expertise making it popular. Ultrasound can define surgical anatomy, rent size, contents, etiological /recurrence factors in great detail and with authority hence accidental findings in a planned surgical procedure can be easily avoided. Clinical dynamic valselva and reducibility test can better documented by real time ultrasound study. In case of recurrence, Sonography will help in assessing the hernia details better as being dynamic real time investigation. Ultrasound signs in case of internal hernias are well comparable with CT findings.

Keywords: laparoscopic repair, Hernia, CT findings, chronic pain

Procedia PDF Downloads 497

Authors: Bishakha Majumdar, Ranjeet Nambudiri

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Considerable dichotomy exists in research regarding the role of optimism and self-efficacy in work and career outcomes. Optimism and self-efficacy are related to performance, commitment and engagement, but also are implicated in seeing opportunities outside the firm and switching jobs. There is absence of research capturing these opposing strands of findings in the same model and providing a holistic understanding of how the expectancy beliefs operate in case of the working professional. We attempt to bridge this gap by proposing that career-decision self-efficacy and career outcome expectations affect intention to quit through the competitive mediation pathways of internal and external marketability. This model provides a holistic picture of the role of career expectancy beliefs on career outcomes, by considering perceived career opportunities both inside and outside one’s present organization. The understanding extends the application of career expectancy beliefs in the context of career decision-making by the employed individual. Further, it is valuable for reconsidering the effectiveness of hiring and retention techniques used by a firm, as selection, rewards and training programs need to be supplemented by interventions that specifically strengthen the stability pathway.

Keywords: career decision self-efficacy, career outcome expectations, marketability, intention to quit, job mobility

Procedia PDF Downloads 634

Authors: Salima Bouadjela, Fatima Zohra Abdoune, Lahcene Mechernene

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PDLCs are currently considered as promising materials for specific applications such as creation of window blinds controlled by electric field, fog simulators, UV protective glasses, high data storage device etc. We know that the electrical field inside the liquid crystal is low compare with the external electric field [1,2]. An addition of high magnetic and electrical, properties containing compounds to the polymer dispersed liquid crystal (PDLC) will enhance the electrical, optical, and magnetic properties of the PDLC [3,4]. Low Concentration of inorganic nanoparticles TiO2 added to nematic liquid crystals (E7) and also combined with monomers (TPGDA) and cured monomer/LC mixture to elaborate polymer-LC-NP dispersion. The presence of liquid crystal and nanoparticles in TPGDA matrix were conformed and the modified properties of PDLC due to doped nanoparticle were studied and explained by the results of FTIR, POM, UV. Incorporation of nanoparticles modifies the structure of PDLC and thus it makes increase the amount of droplets and decrease in droplet size. we found that the presence of TiO2 nanoparticles leads to a shift the nematic-isotropic transition temperature TNI.

Keywords: nanocomposites, PDLC, phases diagram, TiO2

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Authors: Y. Lacroix, J.-F. Malbranque

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We present a chronological evolution for naval telecommunication networks. We distinguish periods: with or without multiplexers, with switch systems, with federative systems, with medium switching, and with medium switching with wireless networks. This highlights the introduction of new layers and technology in the architecture. These architectures are presented using layer models of transmission, in a unified way, which enables us to integrate pre-existing models. A ship of a naval fleet has internal communications (i.e. applications' networks of the edge) and external communications (i.e. the use of the means of transmission between edges). We propose architectures, deduced from the layer model, which are the point of convergence between the networks on board and the HF, UHF radio, and satellite resources. This modelling allows to consider end-to-end naval communications, and in a more global way, that is from the user on board towards the user on shore, including transmission and networks on the shore side. The new architectures need take care of quality of services for end-to-end communications, the more remote control develops a lot and will do so in the future. Naval telecommunications will be more and more complex and will use more and more advanced technologies, it will thus be necessary to establish clear global communication schemes to grant consistency of the architectures. Our latest model has been implemented in a military naval situation, and serves as the basic architecture for the RIFAN2 network.

Keywords: equilibrium beach profile, eastern tombolo of Giens, potential function, erosion

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Authors: Partha P. Gopmandal, S. Bhattacharyya

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We investigate the thermal end effect on the pseudo-steady state behavior of the isotachophoretic transport of ionic species in a 2-D microchannel. Both ends of the channel are kept at a constant temperature which may lead to significant changes in electrophoretic migration speed. A mathematical model based on Nernst-Planck equations for transport of ions coupled with the equation for temperature field is considered. In addition, the charge conservation equations govern the potential field due to the external electric field. We have computed the equations for ion transport, potential and temperature in a coupled manner through the finite volume method. The diffusive terms are discretized via central difference scheme, while QUICK (Quadratic Upwind Interpolation Convection Kinematics) scheme is used to discretize the convective terms. We find that the thermal end effect has significant effect on the isotachophoretic (ITP) migration speed of the analyte. Our result shows that the ITP velocity for temperature dependent case no longer varies linearly with the applied electric field. A detailed analysis has been made to provide a range of the key parameters to minimize the Joule heating effect on ITP transport of analytes.

Keywords: finite volume method, isotachophoresis, QUICK scheme, thermal effect

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Authors: Jennifer Stephens, Nichole Parker, Kristin Petrovic

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To gain a better understanding of how students enrolled in a Bachelor of Nursing (BN) program are educated, faculty members in the BN program at Athabasca University (AU) in Alberta, Canada, developed a 3-phase comprehensive curriculum review project. Phase one of this review centered around hiring an external curriculum expert to examine and analyze the current curriculum and to propose recommendations focused on identifying gaps as well as building on strengths towards meeting changing health care trends. Phase two incorporated extensive institutional document analysis as well as qualitative and quantitative data collection in reciprocated critical reflection and has yielded insights into valuable processes, challenges, and solutions inherent to the complexities of undertaking curriculum review and analysis. Results of our phase one and two analysis generated a quality improvement (QI) template that could benefit other nursing education programs engaged in curriculum review and analysis. The key processes, lessons, and insights, as well as future project phase three plans, will be presented for iterative discussion and role modelling for other institutions undergoing, or planning, content-based curriculum review and evaluation.

Keywords: curriculum, education, nursing, nursing faculty practice, quality improvement

Procedia PDF Downloads 146

Authors: Jia-Jang Wu

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This paper presents the scaling laws that provide the criteria of geometry and dynamic similitude between the full-size rotor-shaft system and its scale model, and can be used to predict the torsional vibration characteristics of the full-size rotor-shaft system by manipulating the corresponding data of its scale model. The scaling factors, which play fundamental roles in predicting the geometry and dynamic relationships between the full-size rotor-shaft system and its scale model, for torsional free vibration problems between scale and full-size rotor-shaft systems are firstly obtained from the equation of motion of torsional free vibration. Then, the scaling factor of external force (i.e., torque) required for the torsional forced vibration problems is determined based on the Newton’s second law. Numerical results show that the torsional free and forced vibration characteristics of a full-size rotor-shaft system can be accurately predicted from those of its scale models by using the foregoing scaling factors. For this reason, it is believed that the presented approach will be significant for investigating the relevant phenomenon in the scale model tests.

Keywords: torsional vibration, full-size model, scale model, scaling laws

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Authors: Mohammed M. Algaradah

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A chelating mercapto- nanoscavenger has been developed exploiting the high surface area of monodisperse nano-sized mesoporous silica. The nanoscavenger acts as a solid phase trace metal extractant whilst suspended as a quasi-stable sol in aqueous samples. This mode of extraction requires no external agitation as the particles move naturally through the sample by Brownian motion, convection and slow sedimentation. Careful size selection enables the nanoscavenger to be easily recovered together with the extracted analyte by conventional filtration or centrifugation. The research describes the successful attachment of chelator mercapto to ca. 136 ± 15 nm high surface area (BET surface area = 1006 m2 g-1) mesoporous silica particles. The resulting material had a copper capacity of ca. 1.34 ± 0.10 mmol g-1 and was successfully applied to the collection of a trace element from water. Essentially complete recovery of Cu (II) has been achieved from freshwater samples giving typical preconcentration factors of 100 from 50 µg/l samples. Data obtained from a nanoscavenger-based extraction of copper from samples were not significantly different from those obtained by using a conventional colorimetric procedure employing complexation/solvent extraction.

Keywords: nano scavenger, mesoporous silica, trace metal, preconcentration

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Authors: Moataz Medhat, Essam Khalil, Hatem Haridy

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The present study investigates the flame structure of turbulent diffusion flame of synthesis fuel in a 300 KW swirl-stabilized burner. The three-dimensional model adopts a realizable k-ε turbulent scheme interacting with two-dimensional PDF combustion scheme by applying flamelet concept. The study reveals more characteristics on turbulent diffusion flame of synthesis fuel when changing the inlet air swirl number and the burner quarl angle. Moreover, it concerns with studying the effect of flue gas recirculation and staging with taking radiation effect into consideration. The comparison with natural gas was investigated. The study showed two zones of recirculation, the primary one is at the center of the furnace, and the location of the secondary one varies by changing the quarl angle of the burner. The results revealed an increase in temperature in the external recirculation zone as a result of increasing the swirl number of the inlet air stream. Also, it was found that recirculating part of the combustion products decreases pollutants formation especially nitrogen monoxide. The predicted results showed a great agreement when compared with the experiments.

Keywords: gas turbine, syngas, analysis, recirculation

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Authors: H. Vargova, J. Strecka, N. Tomasovicova

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A rigorous analytical treatment, with the help of a concept of negativity, is used to study the quantum and thermal entanglement in an isotropic mixed spin-(1/2,S) Heisenberg dimer. The effect of the spin-S magnitude, as well as the effect of diversity between Landé g-factors of magnetic constituents on system entanglement, is exhaustively analyzed upon the variation of the external magnetic and electric field, respectively. It was identified that the increasing magnitude of the spin-S species in a mixed spin-(1/2,S) Heisenberg dimer with comparative Landé g-factors have always a reduction effect on a degree of the quantum entanglement, but it strikingly shifts the thermal entanglement to the higher temperatures. Surprisingly, out of the limit of identical Landé g-factors, the increasing magnitude of spin-S entities can enhance the system entanglement in both low and high magnetic fields. Besides this, we identify that the analyzed dimer with a high-enough magnitude of the spin-S entities at a sufficiently high magnetic field can exhibit unconventional thermally driven re-entrance between the entangled and unentangled mixed state. The importance of the electric-field stimuli is also discussed in detail.

Keywords: quantum and thermal entantanglement, mixed spin Heisenberg model, negativity, reentrant phase transition

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Authors: A. Yamaoka, S. Yukawa

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Mind wandering is a mental phenomenon of drifting away from a current task or external environment toward inner thought. This research examines the feature of mind wandering which people who have high creativity and high mental health engage in because it is expected that mind wandering which such kind of people engage in may not induce negative affect, although it can improve creativity. Sixty-seven participants were required to complete questionnaires which measured their creativity and mental health. After that, researchers conducted experience sampling method and measured the details of their mind wandering and the situation when mind wandering was generated in daily life for three days. The result showed that high creative people and high mental health people more think about positive things during mind wandering and less think about negative things. In further research, researchers will examine how to induce positive thought during mind wandering and how to inhibit negative thought during mind wandering. Doing so will contribute to improve creative problem solving without generation of negative affect.

Keywords: creativity, experience sampling method, mental health, mind wandering

Procedia PDF Downloads 173

Authors: Nelson Nenuwe

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The behavior of interacting electrons in one dimension was studied by calculating correlation functions and critical exponents at zero and external magnetic fields for arbitrary band filling. The technique employed in this study is based on the conformal field theory (CFT). The charge and spin degrees of freedom are separated, and described by two independent conformal theories. A detailed comparison of the t-J model with the repulsive Hubbard model was then undertaken with emphasis on their Tomonaga-Luttinger (TL) liquid properties. Near half-filling the exponents of the t-J model take the values of the strong-correlation limit of the Hubbard model, and in the low-density limit the exponents are those of a non-interacting system. The critical exponents obtained in this study belong to the repulsive TL liquid (conducting phase) and attractive TL liquid (superconducting phase). The theoretical results from this study find applications in one-dimensional organic conductors (TTF-TCNQ), organic superconductors (Bechgaard salts) and carbon nanotubes (SWCNTs, DWCNTs and MWCNTs). For instance, the critical exponent at from this study is consistent with the experimental result from optical and photoemission evidence of TL liquid in one-dimensional metallic Bechgaard salt- (TMTSF)2PF6.

Keywords: critical exponents, conformal field theory, Hubbard model, t-J model

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Authors: Amina Oukennou, Zitouni Beidouri, Otmane Bouksour

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Small to Medium-sized enterprises are a very important component of the economy. They are present in the whole industries all over the world. They are considered as the engine for future growth in the economy. Project management is an economical international factor impacting all types of enterprises including the SMEs. This paper has the aim of measuring the weight of using projects and project management in Moroccan SMEs in comparison with the large companies. The study is based on interviews with experts: project managers, managers, directors, and consultants. They were asked questions measuring the weight of using projects, the level of using project management, and the resources employed. Eighteen Moroccan companies from a range of industries and sizes were consulted. All the companies consider projects as a key element in their strategy. Most of them affirm the great usefulness of the approach 'project', especially for the external activities. The main differences lie in the duration and the size of used projects. Despite the commonly shared idea about the importance of the project management, the interviewed persons believe that the project management knowledge has the same importance or less than the technical knowledge. All the companies affirm the need for a simpler version of project management. The content varies from one company to another.

Keywords: project dimension, project management, small to medium-sized entreprise, Morocco

Procedia PDF Downloads 316

Authors: Bo Wang

Abstract:

As the first high-resolution civil optical satellite, ZY-3 satellite is able to obtain high-resolution multi-view images with three linear array sensors. The images can be used to generate Digital Elevation Models (DEM) through dense matching of stereo images. However, due to the clouds, forest, water and buildings covered on the images, there are some problems in the dense matching results such as outliers and areas failed to be matched (matching holes). This paper introduced an algorithm to verify the accuracy of DEM that generated by ZY-3 satellite with Shuttle Radar Topography Mission (SRTM). Since the accuracy of SRTM (Internal accuracy: 5 m; External accuracy: 15 m) is relatively uniform in the worldwide, it may be used to improve the accuracy of ZY-3 DEM. Based on the analysis of mass DEM and SRTM data, the processing can be divided into two aspects. The registration of ZY-3 DEM and SRTM can be firstly performed using the conjugate line features and area features matched between these two datasets. Then the ZY-3 DEM can be refined by eliminating the matching outliers and filling the matching holes. The matching outliers can be eliminated based on the statistics on Local Vector Binning (LVB). The matching holes can be filled by the elevation interpolated from SRTM. Some works are also conducted for the accuracy statistics of the ZY-3 DEM.

Keywords: ZY-3 satellite imagery, DEM, SRTM, refinement

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Authors: Yuanhao Gao, Pin Lin, Kees Weijer

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In this paper, we will determine the external body force distribution with analysis of stokes fluid motion using mathematical modelling and numerical approaching. The body force distribution is regarded as the unknown variable and could be determined by the idea of optimal control theory. The Stokes flow motion and its velocity are generated by given forces in a unit square domain. A regularized objective functional is built to match the numerical result of flow velocity with the generated velocity data. So that the force distribution could be determined by minimizing the value of objective functional, which is also the difference between the numerical and experimental velocity. Then after utilizing the Lagrange multiplier method, some partial differential equations are formulated consisting the optimal control system to solve. Finite element method and conjugate gradient method are used to discretize equations and deduce the iterative expression of target body force to compute the velocity numerically and body force distribution. Programming environment FreeFEM++ supports the implementation of this model.

Keywords: optimal control model, Stokes equation, finite element method, conjugate gradient method

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Authors: B. C. Biermann

Abstract:

This in-depth exploration investigates the transformative integration of urban vibrancy into contemporary interior design through the strategic incorporation of vivid wall pieces. Bridging the gap between public dynamism and private tranquility, this study delves into the nuanced methodologies, creative processes, and profound impacts of this innovative approach. Drawing inspiration from street art's dynamic language and the timeless allure of natural beauty, these artworks serve as conduits, orchestrating a dialogue that challenges traditional boundaries and redefines the relationship between external chaos and internal sanctuaries. The fusion of urban vibrancy with contemporary interior design represents a paradigm shift, where the inherent dynamism of public spaces harmoniously converges with the curated tranquility of private environments. This paper aims to explore the underlying principles, creative processes, and transformative impacts of integrating vivid wall pieces as instruments for bringing the "outside in." Employing an innovative and meticulous methodology, street art elements are synthesized with the refined aesthetics of contemporary design. This delicate balance necessitates a nuanced understanding of both artistic realms, ensuring a synthesis that captures the essence of urban energy while seamlessly blending with the sophistication of modern interior design. The creative process involves a strategic selection of street art motifs, colors, and textures that resonate with the organic beauty found in natural landscapes, creating a symbiotic relationship between the grittiness of the streets and the elegance of interior spaces. This groundbreaking approach defies traditional boundaries by integrating dynamic street art into interior spaces, blurring the demarcation between external chaos and internal tranquility. Vivid wall pieces serve as dynamic focal points, transforming physical spaces and challenging conventional perceptions of where art belongs. This redefinition asserts that boundaries are fluid and meant to be transcended. Case studies illustrate the profound impact of integrating vivid wall pieces on the aesthetic appeal of interior spaces. Urban vibrancy revitalizes the atmosphere, infusing it with palpable energy that resonates with the vivacity of public spaces. The curated tranquility of private interiors coexists harmoniously with the dynamic visual language of street art, fostering a unique and evolving relationship between inhabitants and their living spaces. Emphasizing harmonious coexistence, the paper underscores the potential for a seamless dialogue between public urban spaces and private interiors. The integration of vivid wall pieces acts as a bridge rather than a dichotomy, merging the dynamism of street art with the curated elegance of contemporary design. This unique visual tapestry transcends traditional categorizations, fostering a symbiotic relationship between contrasting worlds. In conclusion, this paper posits that the integration of vivid wall pieces represents a transformative tool for contemporary interior design, challenging and redefining conventional boundaries. By strategically bringing the "outside in," this approach transforms interior spaces and heralds a paradigm shift in the relationship between urban aesthetics and contemporary living. The ongoing narrative between urban vibrancy and interior design creates spaces that reflect the dynamic and ever-evolving nature of the surrounding environment.

Keywords: Art Integration, Contemporary Interior Design, Interior Space Transformation, Vivid Wall Pieces

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Authors: Niyati Sharma, Om Anand, Sanjeev Kumar Prasad

Abstract:

Assuming future sale value for any of the organizations is one of the major essential characteristics of tactical development. Walmart Sales Forecasting is the finest illustration to work with as a beginner; subsequently, it has the major retail data set. Walmart uses this sales estimate problem for hiring purposes also. We would like to analyzing how the internal and external effects of one of the largest companies in the US can walk out their Weekly Sales in the future. Demand forecasting is the planned prerequisite of products or services in the imminent on the basis of present and previous data and different stages of the market. Since all associations is facing the anonymous future and we do not distinguish in the future good demand. Hence, through exploring former statistics and recent market statistics, we envisage the forthcoming claim and building of individual goods, which are extra challenging in the near future. As a result of this, we are producing the required products in pursuance of the petition of the souk in advance. We will be using several machine learning models to test the exactness and then lastly, train the whole data by Using linear regression and fitting the training data into it. Accuracy is 8.88%. The extra trees regression model gives the best accuracy of 97.15%.

Keywords: random forest algorithm, linear regression algorithm, extra trees classifier, mean absolute error

Procedia PDF Downloads 149

Authors: Shimony Agrawal

Abstract:

In this continually evolving world, change is the most imperative component of our identity. The term alteration alludes to degree by which an individual adapts to inward strains, needs, clashes and can bring coordination between his internal requests and those forced by the external world. Adjustment is a way of managing various demands of life. . Entering school is a defining moment for school first year recruits in their adulthood. The progress from school to school can be rationally and in addition physically troubling. Students deal with a unique amount of stressors when they enter college. Introductory months of school are loaded with apprehension and attempting to fit in the new condition. Colleges and schools should ensure their understudies are balanced in the new condition by giving help at whatever point vital.. The main objective of the study was a comparative analysis of adjustment level with respect to overall adjustment level, gender and living environment. This research has been conducted using Adjustment Inventory for College Students (AICS). The total population is comprised of 240 college-going students. The data majority of the population scored poorly on Emotional Adjustment. Also, female students faced more adjustment problems as compared to male students. However, no significant change was noticed in living environment of the students.

Keywords: adjustment, college students, freshmen year, senior year

Procedia PDF Downloads 260

Authors: Nancy Sakr, Mohamed Abou-Zeid

Abstract:

World energy consumption has increased rapidly in the past few years. Due to population growth, total energy consumption is increasing; a large amount of energy is wasted on the cooling and heating processes in buildings. However, using thermal heating management can minimize costs, heat consumption and create a management system for the heat insulation for buildings. This concept is being implemented through different approaches. Based on analysis and research, there is evidence in the energy consumption before and after testing and applying construction approaches for thermal heating management in building units. This investigation addresses the evaluation of the influence of external coatings on energy consumption. Coatings are considered one of the smart effective available approaches for energy efficiency. Unfortunately, this approach is not widely applied in the construction industry. It needs more data to prove effectiveness and credibility between people to use it as a smart thermal insulation approach. Two precedents have been analyzed in order to monitor buildings’ heat exposure, and how the buildings will be affected by thermal insulation materials. Data sheets from chemical companies which produce similar coatings are compared with the usual products and the protective thermal products.

Keywords: energy consumption, building envelope, thermal insulation, protective coatings

Procedia PDF Downloads 144

Authors: Maria Ahmadnezhad, Seyedgharani Ghoreishi ‎

Abstract:

Electrohydraulic servo system have been used in industry in a wide ‎number of applications. Its ‎dynamics are highly nonlinear and also ‎have large extent of model uncertainties and external ‎disturbances. ‎In this thesis, a robust back-stepping control (RBSC) scheme is ‎proposed to overcome ‎the problem of disturbances and system ‎uncertainties effectively and to improve the set-point ‎performance ‎of EHS systems. In order to implement the proposed control ‎scheme, the system ‎uncertainties in EHS systems are considered as ‎total leakage coefficient and effective oil volume. In ‎addition, in ‎order to obtain the virtual controls for stabilizing system, the ‎update rule for the ‎system uncertainty term is induced by the ‎Lyapunov control function (LCF). To verify the ‎performance and ‎robustness of the proposed control system, computer simulation of ‎the ‎proposed control system using Matlab/Simulink Software is ‎executed. From the computer ‎simulation, it was found that the ‎RBSC system produces the desired set-point performance and ‎has ‎robustness to the disturbances and system uncertainties of ‎EHS systems.‎

Keywords: electro hydraulic servo system, back-stepping control, robust back-‎stepping control, Lyapunov redesign‎

Procedia PDF Downloads 1004