Search results for: performance control

Authors: Arūnas Burinskas

Abstract:

Although Europe is on the threshold of a new industrial revolution called Industry 4.0, many believe that this will increase the flexibility of production, the mass adaptation of products to consumers and the speed of their service; it will also improve product quality and dramatically increase productivity. However, as expected, all the benefits of Industry 4.0 face many of the inevitable changes and challenges they pose. One of them is the inevitable transformation of current competition and business models. This article examines the possible results of competitive conversion from the classic Bertrand and Cournot models to qualitatively new competition based on innovation. Ability to deliver a new product quickly and the possibility to produce the individual design (through flexible and quickly configurable factories) by reducing equipment failures and increasing process automation and control is highly important. This study shows that the ongoing transformation of the competition model is changing the game. This, together with the creation of complex value networks, means huge investments that make it particularly difficult for small and medium-sized enterprises. In addition, the ongoing digitalization of data raises new concerns regarding legal obligations, intellectual property, and security.

Keywords: Bertrand and Cournot Competition, competition model, industry 4.0, industrial organisation, monopolistic competition

Procedia PDF Downloads 129

Authors: Jacquelene Swanepoel, J. C. Visagie, H. M. Linde

Abstract:

Purpose: The aim of this article is to investigate the psychosocial risk environment influencing employee behaviour, and subsequently the trust relationship between employer and employee. Design/methodology/approach: The unique nature and commonness of negative acts, such as unsafe behaviour, human errors, poor performance and negligence, also referred to as unsafe practice, are explored. A literature review is formulated to investigate the nature of negative acts or unsafe behaviour. The findings of this study are used to draw comparisons between unsafe behaviour/misconduct and accidents in the workplace and finally conclude how it should be addressed from a labour relations point of view. Findings: The results indicate comparisons between unsafe practice/misconduct and occupational injuries and accidents, as a result of system flaws, human error or psychosocial risk.

Keywords: occupational risks, unsafe practice, misconduct, organisational safety culture, ergonomics, management commitment and leadership, labour relations

Procedia PDF Downloads 348

Authors: Juhi Kaushik, Abhishek Agarwal, Manoj Sarda, Vatsal Sanjay, Arup Kumar Das

Abstract:

Fire accidents in trains bring huge disaster to human life and property. Evacuation becomes a major challenge in such incidents owing to confined spaces, large passenger density and trains moving at high speeds. The pantry car in Indian Railways trains carry inflammable materials like cooking fuel and LPG and electrical fittings. The pantry car is therefore highly susceptible to fire accidents. Numerical simulations have been done in a pantry car of Indian locomotive train using computational fluid dynamics based software. Different scenarios of a fire outbreak have been explored by varying Heat Release Rate per Unit Area (HRRPUA) of the fire source, introduction of exhaust in the cooking area, and taking a case of an air conditioned pantry car. Temporal statures of flame and soot have been obtained for each scenario and differences have been studied and reported. Inputs from this study can be used to assess casualties in fire accidents in locomotive trains and development of smoke control/detection systems in Indian trains.

Keywords: fire propagation, flame contour, pantry fire, soot flow

Procedia PDF Downloads 329

Authors: Dipak Sonawane, Sudarshan Daga, Somesh Gupta

Abstract:

Quantitative risk assessment (QRA) is a very precise and consistent approach to defining the likelihood, consequence and severity of a major incident/accident. A variety of hazardous cargoes in bulk, such as hydrocarbons and flammable/toxic chemicals, are handled at various ports. It is well known that most of the operations are hazardous, having the potential of damaging property, causing injury/loss of life and, in some cases, the threat of environmental damage. In order to ensure adequate safety towards life, environment and property, the application of scientific methods such as QRA is inevitable. By means of these methods, comprehensive hazard identification, risk assessment and appropriate implementation of Risk Control measures can be carried out. In this paper, the authors, based on their extensive experience in Risk Analysis for ports and harbors, have exhibited how QRA can be used in practice to minimize and contain risk to tolerable levels. A specific case involving the operation for unloading of hydrocarbon at a port is presented. The exercise provides confidence that the method of QRA, as proposed by the authors, can be used appropriately for the identification of hazards and risk assessment of Ports and Terminals.

Keywords: quantitative risk assessment, hazard assessment, consequence analysis, individual risk, societal risk

Procedia PDF Downloads 69

Authors: Sara Heidari, Jafar Mohammadzadeh Milani, Elmira Pouladi Borj

Abstract:

In this research, stability of Ochratoxin A (OTA) during bread making process including fermentation with yeasts (Saccharomyces cerevisiae) and Sourdough (Lactobacillus casei, Lactobacillus rhamnosus, Lactobacillus acidophilus and Lactobacillus fermentum) and baking at 200°C were examined. Bread was prepared on a pilot-plant scale by using wheat flour spiked with standard solution of OTA. During this process, mycotoxin levels were determined after fermentation of the dough with sourdough and three types of yeast including active dry yeast, instant dry yeast and compressed yeast after further baking 200°C by high performance liquid chromatography (HPLC) with fluorescence detector after extraction and clean-up on an immunoaffinity column. According to the results, the highest stability of was observed in the first fermentation (first proof), while the lowest stability was observed in the baking stage in comparison to contaminated flour. In addition, compressed yeast showed the maximum impact on stability of OTA during bread making process.

Keywords: Ochratoxin A, bread, dough, yeast, sourdough

Procedia PDF Downloads 564

Authors: Chungkuk Jin, Moohyun Kim, Woo Chul Chung

Abstract:

This paper presents global performance and dynamic behaviors of a discrete-pontoon-type floating bridge with mooring lines in time domain under wind and wave excitations. The structure is designed for long-distance and deep-water crossing and consists of the girder, columns, pontoons, and mooring lines. Their functionality and behaviors are investigated by using elastic-floater/mooring fully-coupled dynamic simulation computer program. Dynamic wind, first- and second-order wave forces, and current loads are considered as environmental loads. Girder’s dynamic responses and mooring tensions are analyzed under different analysis methods and environmental conditions. Girder’s lateral responses are highly influenced by the second-order wave and wind loads while the first-order wave load mainly influences its vertical responses.

Keywords: floating bridge, mooring line, pontoon, wave excitation

Procedia PDF Downloads 119

Authors: Mekhannene Amine

Abstract:

In this paper, we began in the first step by two-dimensional simulation of a CIGS solar cell, in order to increase the current record efficiency of 20.48% for a single CIGS cell. Was created by utilizing a set of physical and technological parameters a solar cell of reference (such as layer thicknesses, gallium ratio, doping levels and materials properties) documented in bibliography and very known in the experimental field. This was accomplished through modeling and simulation using Atlas SILVACO-TCAD, an tool two and three dimensions very powerful and very adapted. This study has led us to determine the influence of different environmental parameters such as illumination (G) and temperature (T). In the second step, we continued our study by determining the influence of physical parameters (the acceptor of concentration NA) and geometric (thickness t) of the CIGS absorber layer, were varied to produce an optimum efficiency of 24.36%. This approach is promising to produce a CIGS classic solar cell to conduct a maximum performance.

Keywords: solar cell, cigs, photovoltaic generator, illumination, temperature, Atlas SILVACO-TCAD

Procedia PDF Downloads 636

Authors: Jiaying Zhang, Xin Mu, Chang Ni, Jeff L. Zhang

Abstract:

Magnetic resonance elastography (MRE) non-invasively assesses tissue elastic properties, such as shear modulus, by measuring tissue’s displacement in response to mechanical waves. The estimated metrics on tissue elasticity or stiffness have been shown to be valuable for monitoring physiologic or pathophysiologic status of tissue, such as a tumor or fatty liver. To quantify tissue shear modulus from MRE-acquired displacements (essentially an inverse problem), multiple approaches have been proposed, including Local Frequency Estimation (LFE) and Direct Inversion (DI). However, one common problem with these methods is that the estimates are severely noise-sensitive due to either the inverse-problem nature or noise propagation in the pixel-by-pixel process. With the advent of deep learning (DL) and its promise in solving inverse problems, a few groups in the field of MRE have explored the feasibility of using DL methods for quantifying shear modulus from MRE data. Most of the groups chose to use real MRE data for DL model training and to cut training images into smaller patches, which enriches feature characteristics of training data but inevitably increases computation time and results in outcomes with patched patterns. In this study, simulated wave images generated by Finite Differential Time Domain (FDTD) simulation are used for network training, and U-Net is used to extract features from each training image without cutting it into patches. The use of simulated data for model training has the flexibility of customizing training datasets to match specific applications. The proposed method aimed to estimate tissue shear modulus from MRE data with high robustness to noise and high model-training efficiency. Specifically, a set of 3000 maps of shear modulus (with a range of 1 kPa to 15 kPa) containing randomly positioned objects were simulated, and their corresponding wave images were generated. The two types of data were fed into the training of a U-Net model as its output and input, respectively. For an independently simulated set of 1000 images, the performance of the proposed method against DI and LFE was compared by the relative errors (root mean square error or RMSE divided by averaged shear modulus) between the true shear modulus map and the estimated ones. The results showed that the estimated shear modulus by the proposed method achieved a relative error of 4.91%±0.66%, substantially lower than 78.20%±1.11% by LFE. Using simulated data, the proposed method significantly outperformed LFE and DI in resilience to increasing noise levels and in resolving fine changes of shear modulus. The feasibility of the proposed method was also tested on MRE data acquired from phantoms and from human calf muscles, resulting in maps of shear modulus with low noise. In future work, the method’s performance on phantom and its repeatability on human data will be tested in a more quantitative manner. In conclusion, the proposed method showed much promise in quantifying tissue shear modulus from MRE with high robustness and efficiency.

Keywords: deep learning, magnetic resonance elastography, magnetic resonance imaging, shear modulus estimation

Procedia PDF Downloads 50

Authors: Omar A. A. Shaebi, Matouk M. Elamari, Salaheddin Allid

Abstract:

The Information Computing System of Monitoring (ICSM) for the Research Reactor of Tajoura Nuclear Research Centre (TNRC) stopped working since early 1991. According to the regulations, the computer is necessary to operate the reactor up to its maximum power (10 MW). The fund is secured via IAEA to develop a modern computer based data acquisition system to replace the old computer. This paper presents the development of the Labview based data acquisition system to allow automated measurements using National Instruments Hardware and its labview software. The developed system consists of SCXI 1001 chassis, the chassis house four SCXI 1100 modules each can maintain 32 variables. The chassis is interfaced with the PC using NI PCI-6023 DAQ Card. Labview, developed by National Instruments, is used to run and operate the DAQ System. Labview is graphical programming environment suited for high level design. It allows integrating different signal processing components or subsystems within a graphical framework. The results showed system capabilities in monitoring variables, acquiring and saving data. Plus the capability of the labview to control the DAQ.

Keywords: data acquisition, labview, signal conditioning, national instruments

Procedia PDF Downloads 484

Authors: Anubhav Thakur, Karam Chand Dhiman

Abstract:

Storage experiment was conducted to study the effect of polymer, fungicides and insecticide on seed quality parameters and storability in wheat. The experimental material consisted of carry over wheat seeds (variety HPW- 155) of rabi 2017 - 18. The observations were recorded bimonthly on parameters viz; germination (%), seedling length (cm), dry weight (g), vigour index - I, vigour - II, speed of germination, field emergence (%), 100 seed weight (g) for 12 months of storage. All parameters declined with the advancement in storage period. The results showed that seeds treated with polymer + vitavax 200 @ 2 g/kg of seed recorded higher germination percentage (95.00 %), seedling length (17.58 cm), seedling dry weight (0.0138 g), vigour index - I (1670) & vigour - II (1.311), speed of germination (19.98), 100 seed weight (5.54 g) and field emergence (87.33 %) which was at par with vitavax 200 @ 2 g/kg of seed, over untreated control (T1). So it can be concluded that for maintain seed quality and enhancing storability, seed of wheat can either be treated with polymer @ 3 ml/kg of seed + vitavax 200 @ 2 g/kg of seed or vitavax 200 @ 2 g/kg of seed.

Keywords: wheat, seed treatment, storability, seed quality

Procedia PDF Downloads 159

Authors: Francesco Morgan Bono, Simone Cinquemani

Abstract:

This research aims to enhance bridge monitoring by employing innovative techniques that incorporate exogenous factors into the modeling of sensor signals, thereby improving long-term predictability beyond traditional static methods. Using real datasets from two different bridges equipped with Linear Variable Displacement Transducer (LVDT) sensors, the study investigates the fundamental principles governing sensor behavior for more precise long-term forecasts. Additionally, the research evaluates performance on noisy and synthetically damaged data, proposing a residual-based alarm system to detect anomalies in the bridge. In summary, this novel approach combines advanced modeling, exogenous factors, and anomaly detection to extend prediction horizons and improve preemptive damage recognition, significantly advancing structural health monitoring practices.

Keywords: structural health monitoring, dynamic models, sindy, railway bridges

Procedia PDF Downloads 20

Authors: Fauzi Jarushi, Sinan Mohsin AlKaabi

Abstract:

The Standard Penetration Test (SPT) is the most common insitu test for soil investigations. On the other hand, the Cone Penetration Test (CPT) is considered one of the best investigation tools. Due to the fast and accurate results that can be obtained it complaints the SPT in many applications like field explorations, design parameters, and quality control assessments. Many soil index and engineering properties have been correlated to both of SPT and CPT. Various foundation design methods were developed based on the outcome of these tests. Therefore it is vital to correlate these tests to each other so that either one of the tests can be used in the absence of the other, especially for preliminary evaluation and design purposes. The primary purpose of this study was to investigate the relationships between the SPT and CPT for different types of soil in Florida. Data for this research were collected from number of projects sponsored by the Florida Department of Transportation (FDOT), six sites served as the subject of SPT-CPT correlations. The correlations were established between the cone resistance (qc) and the SPT blows (i.e., N) for various soils. A positive linear relationship was found between fs and N for various soils. In general, qc versus N showed higher correlation coefficients than fs versus N. qc/N ratios were developed for different soil types and compared to literature values, the results of this research revealed higher ratios than literature values.

Keywords: in situ tests, correlation, SPT, CPT

Procedia PDF Downloads 387

Authors: Abdulaziz Alageel, Martino Luis, Shuya Zhong

Abstract:

The main focus of this research study is on the challenges faced in decision-making in a supply chain network regarding the facility location while considering carbon emissions. The study aims (i) to locate facilities (i.e., distribution centeres) in a continuous space considering limitations of capacity and the costs associated with opening and (ii) to reduce the cost of carbon emissions by selecting the mode of transportation. The problem is formulated as mixed-integer linear programming. This study hybridised a greedy randomised adaptive search (GRASP) and variable neighborhood search (VNS) to deal with the problem. Well-known datasets from the literature (Brimberg et al. 2001) are used and adapted in order to assess the performance of the proposed method. The proposed hybrid method produces encouraging results based on computational analysis. The study also highlights some research avenues for future recommendations.

Keywords: supply chain, facility location, weber problem, sustainability

Procedia PDF Downloads 90

Authors: N. Bouhamou, F. Mostefa, A. Mebrouki, N. Belas

Abstract:

Every year, millions of cube meters are dredged from dams and restraints as an entertaining and prevention procedure all over the world. These dredged sediments are considered as natural waste leading to an environmental, ecological and even an economical problem in their processing and deposing. Nevertheless, in the context of the sustainable development policy, a way of management is opened aiming to the valorization of sediments as a building material and particularly as a new binder that can be industrially exploited and that improve the physical, chemical and mechanical characteristics of the concrete. This study is a part of the research works realized in the civil engineering department at the university of Mostaganem (Algeria), on the impact of the dredged mud of Fergoug dam on the behaviour of self-consolidating concrete in fresh and hardened state, such as the mechanical performance of SCC and its impact on the differed deformations (shrinkage). The work aims to valorize this mud in SCC and to show eventual interactions between constituents. The results obtained presents a good perspectives in order to perform SCC based in calcined mud.

Keywords: sediment, calcination, reuse, self-consolidating concrete, fresh state, hard state, shrinkage

Procedia PDF Downloads 375

Authors: S. Benessam, T. H. Debieche, S. Amiour, A. Chine, S. Khelili

Abstract:

The metallic trace elements (MTE) are present in water and sediments of the rivers with weak concentrations. Several physicochemical parameters (Eh, pH and oxygen dissolved) and chemical processes (adsorption, absorption, complexation and precipitation) as well as nature of the sediments control their mobility. In order to determine the effect of these factors on the mobility of some MTE (Cd, Cr, Cu, Fe, Pb and Zn) in water of the rivers, a two-monthly monitoring of the physicochemical parameters and chemistry of water and sediments of the Nil wadi (Algeria) was carried out during the period from November 2013 to January 2015. The results show that each MTE has its own conditions of mobility and generally are very influence by the variations of the pH and Eh. Under the natural conditions, neutral pH with basic and medium oxidizing, only the lead presented in water with raised values, indicating its solubility in water and its salting out of the sediments. The other MTE present raised concentrations in the sediments, indicating their trapping by adsorption and/or chemical precipitation. The chemical form of each ETM was given by Eh-pH diagrams. The spatio-temporal monitoring of these ETM shows the effect of the rains, the dry periods and the rejects in the variation of their concentrations.

Keywords: chemistry, metallic trace elements, sediment, water

Procedia PDF Downloads 276

Authors: Luca Vascelli, Silvia Iacomini, Giada Gueli, Francesca Cavallini, Carlo Cavallini, Federica Berardo

Abstract:

The study was conducted to evaluate the effect of training on Big 6 + 6 motor skills to promote daily living skills. Precision teaching (PT) suggests that improved speed of the component behaviors can lead to better performance of composite skills. This study assessed the effects of the repeated timed practice of component motor skills on speed and accuracy of composite skills related to daily living skills. An 18 years old adolescent with intellectual disability participated. A pre post probe single-subject design was used. The results suggest that the participant was able to perform the component skills at his individual aims (endurance was assessed). The speed and accuracy of composite skills were increased; stability and retention were also measured for the composite skill after the training.

Keywords: big 6+6, daily living skills, intellectual disability, precision teaching

Procedia PDF Downloads 145

Authors: Fuyan Sun, Guang Wang, Xueyuan Nie

Abstract:

In this study, a plasma electrolytic oxidation (PEO) process was used to form titanium-aluminium oxide coating on aluminized steel. The present work was mainly to study the effects of treatment time of PEO process on properties of the titanium coating. A potentiodynamic polarization corrosion test was employed to investigate the corrosion resistance of the coating. The friction coefficient and wear resistance of the coating were studied by using pin-on-disc test. The thermal transfer behaviours of uncoated and PEO-coated aluminized steels were also studied. It could be seen that treatment time of PEO process significantly influenced the properties of the titanium oxide coating. Samples with a longer treatment time had a better performance for corrosion and wear protection. This paper demonstrated different treatment time could alter the surface behaviour of the coating material.

Keywords: titanium-aluminum oxide, plasma electrolytic oxidation, corrosion, wear, thermal property

Procedia PDF Downloads 346

Authors: Huda Algharib, Amal Algharib, Hanan Algharib, Ali Mohammad Alqudah

Abstract:

Image registration is an important topic for many imaging systems and computer vision applications. The standard image registration techniques such as Mutual information/ Normalized mutual information -based methods have a limited performance because they do not consider the spatial information or the relationships between the neighbouring pixels or voxels. In addition, the amount of image noise may significantly affect the registration accuracy. Therefore, this paper proposes an efficient method that explicitly considers the relationships between the adjacent pixels, where the gradient information of the reference and scene images is extracted first, and then the cosine similarity of the extracted gradient information is computed and used to improve the accuracy of the standard normalized mutual information measure. Our experimental results on different data types (i.e. CT, MRI and thermal images) show that the proposed method outperforms a number of image registration techniques in terms of the accuracy.

Keywords: image registration, mutual information, image gradients, image transformations

Procedia PDF Downloads 237

Authors: Senesh Wijayarathne

Abstract:

This study focuses on how someone could develop a Buffer Overflow and could use that to exploit the SLMail Server. This study uses a Kali Linux V2018.4 Virtual Machine and Windows 7 - Internet Explorer V8 Virtual Machine (IPv4 Address - 192.168.56.107). This study starts by sending continued bytes to the SLMail Server to find the crashing point range and creating a unique pattern of the length of the crashing point range to control the Extended Instruction Pointer (EIP). Then by sending all characters to SLMail Server, we could observe and find which characters are not rendered properly by the software, also known as Bad Characters. By finding the ‘Jump to the ESP register (JMP ESP) and with the help of ‘Mona Modules’, we could use msfvenom to create a non-stage windows reverse shell payload. By including all the details gathered previously on one script, we could get a system-level reverse shell of the Windows 7 PC. The end of this paper will discuss how to mitigate this vulnerability.

Keywords: slmail server, extended instruction pointer, jump to the esp register, bad characters, virtual machine, windows 7, kali Linux, buffer overflow, Seattle lab, vulnerability

Procedia PDF Downloads 148

Authors: Pitimanus Bunlue

Abstract:

This research aim (1) to determine the content of communication, social capital and cultural capital to promote tourism in the province to create awareness, motivation and desire to tourists visiting Thailand (2) to evaluate the performance of innovation communication social capital and cultural capital to promote tourism southern of Thailand. This research is a qualitative research. A research synthesis projects on social capital and cultural capital by use focus group discussions with media professionals and academics to communicate using a random sample specific. The result show that (1) Innovative communication, social capital and cultural capital and effective communication innovations after everyone wants to travel to Ranong province is the very highest level. (2) Information and experience about Ranong at a high level. (3) The data shows the strengths of each of the attractions at a high level. (4) The data shows a lifestyle that is unique to the province is moderate.

Keywords: innovative communication, promoting tourism, southern of Thailand, social capital

Procedia PDF Downloads 266

Authors: Afshin Akhondzadeh Basti, Zohreh Mashak, Ali Khanjari, Mohammad Adel Rezaei, Fatemeh Mohammadkhan

Abstract:

Vibrio parahaemolyticus is a halophilic bacterium and often causes gastroenteritis because of consumption of raw or inadequately cooked seafood. Studies showed a strong association of thermostable direct hemolysin (TDH) produced by members of this species with its pathogenicity. The effects of garlic (Allium sativum) essential oil at concentrations of 0, 0.005, 0.015, 0.03 and 0.045% on the minimum inhibitiotory concentration (MIC), minimum bactericidal concentration (MBC), growth curve and production of TDH toxin of vibrio parahaemolyticus were studied in BHI model. MIC and MBC of Allium sativum essential oil was estimated 0.03%. The results of this study revealed that the TDH production was significantly affected by Allium sativum EO and titers of TDH production in 0 and 0.005 % were 1/256 whereas this titer in 0.015 % concentration of EO. Concentrations of 0.005 and 0/015 % of garlic essential oil reduced the bacterial growth rate significantly (P < 0.05) compared to the control group. According to the results Allium sativum essential oil showed to be effective against bacterial growth and production of TDH toxin. Its potential application in food systems may be suggested.

Keywords: allium sativum essential oil, vibrio parahaemolyticus, TDH, consumption

Procedia PDF Downloads 416

Authors: Samira Naghdi, Kyong Yop Rhee

Abstract:

Transfer-free synthesis of graphene on dielectric substrates is highly desirable but remains challenging. Here, by using a thin sacrificial platinum layer as a catalyst, graphene was deposited on a silicon substrate through a simple and transfer-free synthesis method. During graphene growth, the platinum layer evaporated, resulting in direct deposition of graphene on the silicon substrate. In this work, different growth conditions of graphene were optimized. Raman spectra of the produced graphene indicated that the obtained graphene was bilayer. The sheet resistance obtained from four-point probe measurements demonstrated that the deposited graphene had high conductivity. Reflectance spectroscopy of graphene-coated silicon showed a decrease in reflectance across the wavelength range of 200-800 nm, indicating that the graphene coating on the silicon surface had antireflection capabilities.

Keywords: antireflection coating, chemical vapor deposition, graphene, the sheet resistance

Procedia PDF Downloads 170

Authors: Gülçin Tekin, Fethi Kadıoğlu

Abstract:

In this study, the dynamic analysis of viscoelastic plates with variable thickness is examined. The solutions of dynamic response of viscoelastic thin plates with variable thickness have been obtained by using the functional analysis method in the conjunction with the Gâteaux differential. The four-node serendipity element with four degrees of freedom such as deflection, bending, and twisting moments at each node is used. Additionally, boundary condition terms are included in the functional by using a systematic way. In viscoelastic modeling, Three-parameter Kelvin solid model is employed. The solutions obtained in the Laplace-Carson domain are transformed to the real time domain by using MDOP, Dubner & Abate, and Durbin inverse transform techniques. To test the performance of the proposed mixed finite element formulation, numerical examples are treated.

Keywords: dynamic analysis, inverse laplace transform techniques, mixed finite element formulation, viscoelastic plate with variable thickness

Procedia PDF Downloads 318

Authors: M. A. Akhavan-Behabadi, M. Najafi, A. Abbasi

Abstract:

An empirical investigation was performed in order to study the heat transfer characteristics of R600a flow boiling inside horizontal flattened tubes and the simultaneous effect of nanoparticles on boiling heat transfer in flattened channel. Round copper tubes of 8.7 mm I.D. were deformed into flattened shapes with different inside heights of 6.9, 5.5, and 3.4 mm as test areas. The effect of different parameters such as mass flux, vapor quality and inside height on heat transfer coefficient was studied. Flattening the tube caused significant enhancement in heat transfer performance so that the maximum augmentation ratio of 163% was obtained in flattened channel with lowest internal height. A new correlation was developed based on the present experimental data to predict the heat transfer coefficient in flattened tubes. This correlation estimated 90% of the entire database within ±20%.

Keywords: nano particles, flattend tube, R600a, CuO

Procedia PDF Downloads 313

Authors: Temesgen Yaekob Ergano, Sure Pulla Rao

Abstract:

The study on financial development and economic growth in Sub-Saharan Africa utilizes System GMM analysis to investigate the relationship between financial development indicators and economic performance in the region. The research findings reveal significant impacts of various financial indicators on economic growth, such as the positive influence of bank liquid reserves to bank assets ratio (R/A), trade openness, and the broad money to total reserves ratio (M/R) on the economic growth of Sub-Saharan Africa. Additionally, the study highlights the negative impact of domestic credit provided to the private sector by banks (D_bank) on economic growth, emphasizing the importance of prudent credit allocation to avoid over-indebtedness and financial crises. These results provide valuable insights for policymakers aiming to foster sustainable economic growth in the region by leveraging financial development effectively.

Keywords: financial development, economic growth, Sub-Saharan Africa, system GMM analysis, financial indicators.

Procedia PDF Downloads 36

Authors: Dany Ng Cheong Vee, Preethee Nunkoo Gonpot, Noor Sookia

Abstract:

In this paper, we consider the application of Extreme Value Theory as a risk measurement tool. The Value at Risk, for a set of indices, from six Stock Exchanges of Frontier markets is calculated using the Peaks over Threshold method and the performance of the model index-wise is evaluated using coverage tests and loss functions. Our results show that 'fat-tailedness' alone of the data is not enough to justify the use of EVT as a VaR approach. The structure of the returns dynamics is also a determining factor. This approach works fine in markets which have had extremes occurring in the past thus making the model capable of coping with extremes coming up (Colombo, Tunisia and Zagreb Stock Exchanges). On the other hand, we find that indices with lower past than present volatility fail to adequately deal with future extremes (Mauritius and Kazakhstan). We also conclude that using EVT alone produces quite static VaR figures not reflecting the actual dynamics of the data.

Keywords: extreme value theory, financial crisis 2008, value at risk, frontier markets

Procedia PDF Downloads 266

Authors: Marie-Josée Morneau

Abstract:

A literacy-based approach, centred on the use of the language of instruction as a cognitive tool, can increase the L2 communication skills of French immersion students. Academic subject areas such as science and mathematics offer an authentic language learning context where students can become more proficient speakers while using specific vocabulary and language structures to learn, interact and communicate their reasoning, when provided the opportunities and guidance to do so. In this Canadian quasi-experimental study, the effects of teaching specific language elements during mathematic classes through literacy-based activities in Early French Immersion programming were compared between two Grade 7/8 groups: the experimental group, which received literacy-based teaching for a 6-week period, and the control group, which received regular teaching instruction. The results showed that the participants from the experimental group made more progress in their mathematical communication skills, which suggests that targeting L2 language as a cognitive tool can be beneficial to immersion learners who learn mathematic concepts and remind us that all L2 teachers are language teachers.

Keywords: mathematics, French immersion, literacy-based, oral communication, L2

Procedia PDF Downloads 65

Authors: B. Siva Kumar Reddy, B. Lakshmi

Abstract:

WiMAX has adopted an Adaptive Modulation and Coding (AMC) in OFDM to endure higher data rates and error free transmission. AMC schemes employ the Channel State Information (CSI) to efficiently utilize the channel and maximize the throughput and for better spectral efficiency. This CSI has given to the transmitter by the channel estimators. In this paper, LSE (Least Square Error) and MMSE (Minimum Mean square Error) estimators are suggested and BER (Bit Error Rate) performance has been analyzed. Channel equalization is also integrated with with AMC-OFDM system and presented with Constant Modulus Algorithm (CMA) and Least Mean Square (LMS) algorithms with convergence rates analysis. Simulation results proved that increment in modulation scheme size causes to improvement in throughput along with BER value. There is a trade-off among modulation size, throughput, BER value and spectral efficiency. Results also reported the requirement of channel estimation and equalization in high data rate systems.

Keywords: AMC, CSI, CMA, OFDM, OFDMA, WiMAX

Procedia PDF Downloads 384

Authors: Giti Sabri, Sohrab Imani, Ali Ahadiyat, Aref Maroof, Yahya Ostadi

Abstract:

Recently, there has been a growing interest in research concerning the possible use of plant extracts as alternatives to synthetic insecticides. In this research, the insecticidal effects of Carum copticum essential oils against rice weevil adults were investigated in laboratory condition. Essential oils was extracted through distillation with water using Clevenger apparatus. Tests of randomized complete block included six concentrations and three replications for essential oils (fumigant toxicity) along with control treatment in condition of 27±1ºC degrees Celsius temperature, relative humidity of 65 ± 5 percent and darkness. LC50 values were calculated by SPSS.21.0 software which presented the value of LC50 of Carum copticum essential oils after 48 hurs, 187.35± 0.40 µl/l air on rice weevil adults. Results showed that increasing the concentration of essential oils increased the mortality rate cases. The results also showed that essential oils of Carum copticum are effective biological sources which can effectively protect stored grain from infestation by the rice weevil; although for application of these combinations further research may be needed.

Keywords: insecticidial effects, essential oil, Carum copticum, Sitophilus oryzae

Procedia PDF Downloads 404

Authors: Robert Miller, Fred Soltero, Sandra Allan, Denise Bonilla

Abstract:

The Tropical Bont Tick (TBT), Amblyomma variegatum, was introduced to the Caribbean in the mid-1700s. Since it has spread throughout the Caribbean dispersed by cattle egrets (Bubulcus ibis). Tropical Bont Ticks vector many pathogens to livestock and humans. However, only the livestock diseases heartwater, Ehrlichia (Cowdria) ruminantium, and dermatophilosis, Dermatophilus congolensis, are associated with TBT in the Caribbean. African tick bite fever (Rickettsia africae) is widespread in Caribbean TBT but human cases are rare. The Caribbean Amblyomma Programme (CAP) was an effort led by the Food and Agricultural Organization to eradicate TBTs from participating islands. This 10-year effort successfully eradicated TBT from many islands. However, most are reinfested since its termination. Pheromone technology has been developed to aid in TBT control. Although not part of the CAP treatment scheme, this research established that pheromones in combination with pesticide greatly improves treatment efficiencies. Additionally, pheromone combined with CO₂ traps greatly improves active surveillance success. St. Croix has a history of TBT outbreaks. Passive surveillance detected outbreaks in 2016 and in May of 2021. Surveillance efforts are underway to determine the extent of TBT on St Croix. Puerto Rico is the next island in the archipelago and is at a greater risk of re-infestation due to active outbreaks in St Croix. Tropical Bont Ticks were last detected in Puerto Rico in the 1980s. The infestation started on the small Puerto Rican island of Vieques, the closest landmass to St Croix, and spread to the main island through cattle movements. This infestation was eradicated with the help of the Tropical Cattle Tick (TCT), Rhipicephalus (Boophilus) microplus, eradication program. At the time, large percentages of Puerto Rican cattle were treated for ticks along with the necessary material and manpower mobilized for the effort. Therefore, a shift of focus from the TCT to TBT prevented its establishment in Puerto Rico. Currently, no large-scale treatment of TCTs occurs in Puerto Rico. Therefore, the risk of TBT establishment is now greater than it was in the 1980s. From Puerto Rico, the risk of TBT movement to the American continent increases significantly. The establishment of TBTs in the Americas would cause $1.2 billion USD in losses to the livestock industry per year. The USDA Agricultural Research Service recently worked with the USDA Animal Health Inspection Service and the Puerto Rican Department of Agriculture to modernize the management of the TCT. This modernized program uses safer pesticides and has successfully been used to eradicate pesticide-susceptible and -resistant ticks throughout the island. The objective of this work is to prevent the infestation of Puerto Rico by TBTs by combining the current TCT management efforts with TBT surveillance in Vieques. The combined effort is designed to eradicate TCT from Vieques while using the treated cattle as trap animals for TBT using pheromone impregnated tail tags attached to treated animals. Additionally, active surveillance using CO₂-baited traps combined with pheromone will be used to actively survey the environment for free-living TBT. Knowledge gained will inform TBT control efforts in St. Croix.

Keywords: Amblyomma variegatum, caribbean, eradication, Rhipicephalus (boophilus) microplus, pheromone

Procedia PDF Downloads 160