Search results for: Mohammad Abdallah
1216 The Nubian Ibex’s Distribution, Population, Habitat, and Conservation Status in Sudan’s Red Sea State Over the Past Decade
Authors: Lubna M. A. Hassan, Nasir Brema, Abdallah Mamy, Insaf Yahya, Tanzil A. G., Ahmed M. M. Hasoba, Omer A. Suliman
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The Nubian ibex species has been categorized as vulnerable by the International Union for Conservation of Nature (IUCN) due to a lack of population data in specific regions within their habitat. This species faces numerous challenges, including habitat loss caused by agricultural practices, livestock rearing, mining activity, and infrastructure development. Additionally, competition with non-native species and hunting pose significant threats to their survival. Unfortunately, studies on the distribution, conservation status, ecology, and health of the ibex are limited and primarily descriptive in nature. In order to bridge this knowledge gap, recent surveys were conducted in the Red Sea State of Sudan during specific periods in 2015, 2016, 2019, and 2021. These surveys have provided valuable insights into the distribution, habitats, and conservation status of the Nubian ibex in the Red Sea State. The findings indicate that the Capra nubiana ibex can be found across more than 17 mountains in the Red Sea State. However, the total population estimate from recent years suggests that there are fewer than 250 individuals remaining. The study has also identified the highest altitude at which the Nubian ibex habitats existed in Sudan's Red Sea State, measuring 1675 m. This area harbors a diverse array of Nubian ibex habitats, encompassing a total of 21 wild plant species from 10 distinct families. The region experiences an average annual temperature ranging from 20.64°C in January to 33.30°C in August. Precipitation occurs in November and December, although it is characterized by unreliability and erratic patterns. It is important to note that these population estimates were obtained through surveys conducted in collaboration with rangers and local communities, and adjustments to survey methods are necessary to accommodate the challenging mountainous terrain, such as utilizing aerial surveys. To effectively address these threats, it is imperative to establish comprehensive long-term monitoring programs.Keywords: Nubian ibex, distribution, population, habitats
Procedia PDF Downloads 881215 Effect of Signal Acquisition Procedure on Imagined Speech Classification Accuracy
Authors: M.R Asghari Bejestani, Gh. R. Mohammad Khani, V.R. Nafisi
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Imagined speech recognition is one of the most interesting approaches to BCI development and a lot of works have been done in this area. Many different experiments have been designed and hundreds of combinations of feature extraction methods and classifiers have been examined. Reported classification accuracies range from the chance level to more than 90%. Based on non-stationary nature of brain signals, we have introduced 3 classification modes according to time difference in inter and intra-class samples. The modes can explain the diversity of reported results and predict the range of expected classification accuracies from the brain signal accusation procedure. In this paper, a few samples are illustrated by inspecting results of some previous works.Keywords: brain computer interface, silent talk, imagined speech, classification, signal processing
Procedia PDF Downloads 1531214 Learning Compression Techniques on Smart Phone
Authors: Farouk Lawan Gambo, Hamada Mohammad
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Data compression shrinks files into fewer bits than their original presentation. It has more advantage on the internet because the smaller a file, the faster it can be transferred but learning most of the concepts in data compression are abstract in nature, therefore, making them difficult to digest by some students (engineers in particular). This paper studies the learning preference of engineering students who tend to have strong, active, sensing, visual and sequential learning preferences, the paper also studies the three shift of technology-aided that learning has experienced, which mobile learning has been considered to be the feature of learning that will integrate other form of the education process. Lastly, we propose a design and implementation of mobile learning application using software engineering methodology that will enhance the traditional teaching and learning of data compression techniques.Keywords: data compression, learning preference, mobile learning, multimedia
Procedia PDF Downloads 4481213 A New Approach for Generalized First Derivative of Nonsmooth Functions Using Optimization
Authors: Mohammad Mehdi Mazarei, Ali Asghar Behroozpoor
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In this paper, we define an optimization problem corresponding to smooth and nonsmooth functions which its optimal solution is the first derivative of these functions in a domain. For this purpose, a linear programming problem corresponding to optimization problem is obtained. The optimal solution of this linear programming problem is the approximate generalized first derivative. In fact, we approximate generalized first derivative of nonsmooth functions as tailor series. We show the efficiency of our approach by some smooth and nonsmooth functions in some examples.Keywords: general derivative, linear programming, optimization problem, smooth and nonsmooth functions
Procedia PDF Downloads 5571212 The Necessity and Methods of Abolishing Discrimination and Religious Violence
Authors: Hossein Boroujerdi, Mohammad R. Sadeghi, Maryam Moazen Zadeh
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During the recent decades, the result of religious prophets has lost its attraction, and theology has become disfigured, so it has been made ugly. Undoubtedly, some of existing non-peaceful and harsh rules and measures within the religious books and contexts have been considered as the reasons and excuses for defamation of religions. Based on library sources and also extensive research in Quran and Islamic narratives, this study has aimed to find some alternative solutions and options to abolish and disregard those religious rules which are in contrary of human right charters and standards. The results have demonstrated that some of inhuman religious punishments such as execution, stoning, whipping as well as religious discriminations and warlike behaviors are in contrary of some other religious contexts and concepts. This finding have proved inadaptability between some religious contexts and religious records.Keywords: adjustment and abolishment, discrimination, religious commands and laws, tolerance, violence
Procedia PDF Downloads 2151211 Groundwater Quality Monitoring in the Shoush Suburbs, Khouzestan Province, Iran
Authors: Mohammad Tahsin Karimi Nezhad, Zaynab Shadbahr, Ali Gholami
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In recent years many attempts have been made to assess groundwater contamination by nitrates worldwide. The assessment of spatial and temporal variations of physico-chemical parameters of water is necessary to mange water quality. The objectives of the study were to evaluate spatial variability and temporal changes of hydrochemical factors by water sampling from 24 wells in the Shoush City suburb. The analysis was conducted for the whole area and for different land use and geological classes. In addition, nitrate concentration variability with descriptive parameters such as sampling depth, dissolved oxygen, and on ground nitrogen loadings was also investigated The results showed that nitrate concentrations did not exceed the standard limit (50 mg/l). EC of water samples, ranged from 900 to 1200 µs/cm, TDS from 775 to 830 mg/l and pH from 5.6 to 9.Keywords: groundwater, GIS, water quality, Iran
Procedia PDF Downloads 4311210 Applying a Noise Reduction Method to Reveal Chaos in the River Flow Time Series
Authors: Mohammad H. Fattahi
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Chaotic analysis has been performed on the river flow time series before and after applying the wavelet based de-noising techniques in order to investigate the noise content effects on chaotic nature of flow series. In this study, 38 years of monthly runoff data of three gauging stations were used. Gauging stations were located in Ghar-e-Aghaj river basin, Fars province, Iran. The noise level of time series was estimated with the aid of Gaussian kernel algorithm. This step was found to be crucial in preventing removal of the vital data such as memory, correlation and trend from the time series in addition to the noise during de-noising process.Keywords: chaotic behavior, wavelet, noise reduction, river flow
Procedia PDF Downloads 4691209 A Type-2 Fuzzy Model for Link Prediction in Social Network
Authors: Mansoureh Naderipour, Susan Bastani, Mohammad Fazel Zarandi
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Predicting links that may occur in the future and missing links in social networks is an attractive problem in social network analysis. Granular computing can help us to model the relationships between human-based system and social sciences in this field. In this paper, we present a model based on granular computing approach and Type-2 fuzzy logic to predict links regarding nodes’ activity and the relationship between two nodes. Our model is tested on collaboration networks. It is found that the accuracy of prediction is significantly higher than the Type-1 fuzzy and crisp approach.Keywords: social network, link prediction, granular computing, type-2 fuzzy sets
Procedia PDF Downloads 3271208 Comparative Assessment of ABS and Disk Brake Systems
Authors: Saleh Mobasseri, Mohammad Mobasseri
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The article refers to the history of the rise of brake system and described it’s importance in passenger’s lives. The disc brake system performance and ABS are also compared with each other by the kinetic and kinematic analysis of the braking system,and evaluate the impact of each parameters is checked on the vehicle stopping distance. Anti−lock braking system (ABS) is one of the most important features that affect on vehicle safety and for this reason much efforts have been made to improve this system. The objectives of the anti−lock system (ABS) are as follows: Preventing the wheels from locking, achieving maximum technical momentum in terms of braking,stability,reducing stopping distances. In this paper,we study the comparative of ABS brake and disc brake.Keywords: anti−lock braking System (ABS), stopping distances, booster, car stability, force exerted on the brake pedal
Procedia PDF Downloads 3981207 A Future Technology: Solar Winged Autonomous Underwater Vehicle Design
Authors: Mohammad Moonesun
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One of the most important future technologies is related to solar Autonomous Underwater Vehicles (AUVs). In this technical paper, some aspects of solar winged AUV design are mentioned. The case study is for Arya project. The submarine movement cyclograms, weight quotas for internal equipment, hydrodynamic test results are mentioned, and some other technical notes are discussed here. The main body is the SUBOFF type and has two hydroplanes on the both sides of the body with the NACA0015 cross section. On these two hydroplanes, two 50-W photovoltaic panel will be mounted. Four small hydroplanes with the same cross section of the NACA0015 are arranged at the stern of the body at a 90° angle to each other. This test is performed in National Iranian Marine Laboratory with the length of 402 m.Keywords: AUV, solar, model test, hydrodynamic resistance
Procedia PDF Downloads 1311206 Investigation of the Effect of Nickel Electrodes as a Stainless Steel Buffer Layer on the Shielded Metal Arc Welding
Authors: Meisam Akbari, Seyed Hossein Elahi, Mohammad Mashadgarmeh
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In this study, the effect of nickel-electrode as a stainless steel buffer layer is considered. Then, the effect of dilution of the last layer of welding on two samples of steel plate A516 Gr70 (C-Mn-Si) with SMAW welding process was investigated. Then, in a sample, the ENI-cl nickel electrode was welded as the buffer layer and the E316L-16 electrode as the last layer of welding and another sample with an E316L-16 electrode in two layers. The chemical composition of the latter layer was determined by spectrophotometry method. The results indicate that the chemical composition of the latter layer is different and the lowest dilution rate is obtained using the nickel electrode.Keywords: degree of dilution, C-Mn-Si, spectrometry, nickel electrode, stainless steel
Procedia PDF Downloads 2201205 Urban Design via Estimation Model for Traffic Index of Cities Based on an Artificial Intelligence
Authors: Seyed Sobhan Alvani, Mohammad Gohari
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By developing cities and increasing the population, traffic congestion has become a vital problem. Due to this crisis, urban designers try to present solutions to decrease this difficulty. On the other hand, predicting the model with perfect accuracy is essential for solution-providing. The current study presents a model based on artificial intelligence which can predict traffic index based on city population, growth rate, and area. The accuracy of the model was evaluated, which is acceptable and it is around 90%. Thus, urban designers and planners can employ it for predicting traffic index in the future to provide strategies.Keywords: traffic index, population growth rate, cities wideness, artificial neural network
Procedia PDF Downloads 441204 Biological Control of Fusarium Crown and Root and Tomato (Solanum lycopersicum L.) Growth Promotion Using Endophytic Fungi from Withania somnifera L.
Authors: Nefzi Ahlem, Aydi Ben Abdallah Rania, Jabnoun-Khiareddine Hayfa, Ammar Nawaim, Mejda Daami-Remadi
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Fusarium Crown and Root Rot (FCRR) caused by Fusarium oxysporum f. sp. radicis-lycopersici (FORL) is a serious tomato (Solanum lycopersicum L.) disease in Tunisia. Its management is very difficult due to the long survival of its resting structures and to the luck of genetic resistance. In this work, we explored the wild Solanaceae species Withania somnifera, growing in the Tunisian Centre-East, as a potential source of biocontrol agents effective in FCRR suppression and tomato growth promotion. Seven fungal isolates were shown able to colonize tomato roots, crowns, and stems. Used as conidial suspensions or cell-free culture filtrates, all tested fungal treatments significantly enhanced tomato growth parameters by 21.5-90.3% over FORL-free control and by 27.6-93.5% over pathogen-inoculated control. All treatments significantly decreased the leaf and root damage index by 28.5-92.8 and the vascular browning extent 9.7-86.4% over FORL-inoculated and untreated control. The highest disease suppression ability (decrease by 86.4-92.8% in FCRR severity) over pathogen-inoculated control and by 81.3-88.8 over hymexazol-treated control) was expressed by I6 based treatments. This endophytic fungus was morphologically characterized and identified using rDNA sequencing gene as Fusarium sp. I6 (MG835371). This fungus was shown able to reduce FORL radial growth by 58.5–83.2% using its conidial suspension or cell-free culture filtrate. Fusarium sp. I6 showed chitinolytic, proteolytic and amylase activities. The current study clearly demonstrated that Fusarium sp. (I6) is a promising biocontrol candidate for suppressing FCRR severity and promoting tomato growth. Further investigations are required for elucidating its mechanism of action involved in disease suppression and plant growth promotion.Keywords: antifungal activity, associated fungi, Fusarium oxysporum f. sp. radicis-lycopersici, Withania somnifera, tomato growth
Procedia PDF Downloads 1461203 A Survey on Intelligent Techniques Based Modelling of Size Enlargement Process for Fine Materials
Authors: Mohammad Nadeem, Haider Banka, R. Venugopal
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Granulation or agglomeration is a size enlargement process to transform the fine particulates into larger aggregates since the fine size of available materials and minerals poses difficulty in their utilization. Though a long list of methods is available in the literature for the modeling of granulation process to facilitate the in-depth understanding and interpretation of the system, there is still scope of improvements using novel tools and techniques. Intelligent techniques, such as artificial neural network, fuzzy logic, self-organizing map, support vector machine and others, have emerged as compelling alternatives for dealing with imprecision and complex non-linearity of the systems. The present study tries to review the applications of intelligent techniques in the modeling of size enlargement process for fine materials.Keywords: fine material, granulation, intelligent technique, modelling
Procedia PDF Downloads 3751202 Real Time Adaptive Obstacle Avoidance in Dynamic Environments with Different D-S
Authors: Mohammad Javad Mollakazemi, Farhad Asadi
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In this paper a real-time obstacle avoidance approach for both autonomous and non-autonomous dynamical systems (DS) is presented. In this approach the original dynamics of the controller which allow us to determine safety margin can be modulated. Different common types of DS increase the robot’s reactiveness in the face of uncertainty in the localization of the obstacle especially when robot moves very fast in changeable complex environments. The method is validated by simulation and influence of different autonomous and non-autonomous DS such as important characteristics of limit cycles and unstable DS. Furthermore, the position of different obstacles in complex environment is explained. Finally, the verification of avoidance trajectories is described through different parameters such as safety factor.Keywords: limit cycles, nonlinear dynamical system, real time obstacle avoidance, safety margin
Procedia PDF Downloads 4441201 Developing Fuzzy Logic Model for Reliability Estimation: Case Study
Authors: Soroor K. H. Al-Khafaji, Manal Mohammad Abed
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The research aim of this paper is to evaluate the reliability of a complex engineering system and to design a fuzzy model for the reliability estimation. The designed model has been applied on Vegetable Oil Purification System (neutralization system) to help the specialist user based on the concept of FMEA (Failure Mode and Effect Analysis) to estimate the reliability of the repairable system at the vegetable oil industry. The fuzzy model has been used to predict the system reliability for a future time period, depending on a historical database for the two past years. The model can help to specify the system malfunctions and to predict its reliability during a future period in more accurate and reasonable results compared with the results obtained by the traditional method of reliability estimation.Keywords: fuzzy logic, reliability, repairable systems, FMEA
Procedia PDF Downloads 6161200 Feasibility of Leukemia Cancer Treatment (K562) by Atmospheric Pressure Plasma Jet
Authors: Mashayekh Amir Shahriar, Akhlaghi Morteza, Rajaee Hajar, Khani Mohammad Reza, Shokri Babak
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A new and novel approach in medicine is the use of cold plasma for various applications such as sterilization blood coagulation and cancer cell treatment. In this paper a pin-to-hole plasma jet suitable for biological applications is investigated, characterized and the possibility and feasibility of cancer cell treatment is evaluated. The characterization includes power consumption via Lissajous method, thermal behavior of plasma using Infra-red camera as a novel method, Optical Emission Spectroscopy (OES) to determine the species that are generated. Treatment of leukemia cancer cells is also implemented and MTT assay is used to evaluate viability.Keywords: Atmospheric Pressure Plasma Jet (APPJ), Plasma Medicine, Cancer cell treatment, leukemia, Optical Emission
Procedia PDF Downloads 6611199 Smart Speed Bump
Authors: Mohammad Rahmani Rezaiyeh, Mojtaba Rahmani Rezaiyeh, Mehrdad Rahmani Rezaiyeh
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Smart speed bump is a new invention and I am invented it. Smart speed bump is a system that can change the position of speed bumps either active or passive in necessary situations. The basic system of smart speed bumps is based on a robotic system which includes mechanic, electronic and artificial intelligence. The smart speed bump is capable of smart decision making and can change its position by anticipating the peak of terrific hours. It can be noted to the advantages of this system such as preventing the waste of petrol while crossing speed bumps, traffic management, accelerating, flowing and securing traffic, reducing accidents and judicial records.Keywords: invention, smart, robotic system, speed bump, traffic, management
Procedia PDF Downloads 4191198 Development of a Performance Measurement Model for Hospitals Using Multi-Criteria Decision Making (MCDM) Techniques: A Case Study of Three South Australian Major Public Hospitals
Authors: Mohammad Safaeipour, Yousef Amer
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This study directs its focus on developing a conceptual model to offer a systematic and integrated method to weigh the related measures and evaluate a competence of hospitals and rank of the selected hospitals that involve and consider the stakeholders’ key performance indicators (KPI’s). The Analytical Hierarchy Process (AHP) approach will use to weigh the dimensions and related sub- components. The weights and performance scores will combine by using the Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) and rank the selected hospitals. The results of this study provide interesting insight into the necessity of process improvement implementation in which hospital that received the lowest ranking score.Keywords: performance measurement system, PMS, hospitals, AHP, TOPSIS
Procedia PDF Downloads 3741197 Non-Destructive Visual-Statistical Approach to Detect Leaks in Water Mains
Authors: Alaa Al Hawari, Mohammad Khader, Tarek Zayed, Osama Moselhi
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In this paper, an effective non-destructive, non-invasive approach for leak detection was proposed. The process relies on analyzing thermal images collected by an IR viewer device that captures thermo-grams. In this study a statistical analysis of the collected thermal images of the ground surface along the expected leak location followed by a visual inspection of the thermo-grams was performed in order to locate the leak. In order to verify the applicability of the proposed approach the predicted leak location from the developed approach was compared with the real leak location. The results showed that the expected leak location was successfully identified with an accuracy of more than 95%.Keywords: thermography, leakage, water pipelines, thermograms
Procedia PDF Downloads 3551196 Effects of Strain-Induced Melt Activation Process on the Structure and Morphology Mg₂Si in Al-15%Mg₂Si Composite
Authors: Reza Eslami-Farsani, Mohammad Alipour
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The effect of deformation on the semisolid microstructure and degree of globularity of Al–15%Mg₂Si composite produced by the strain induced melt activation (SIMA) process was studied. Deformation of 25% was used. After deformation, the samples were heated to a temperature above the solidus and below the liquidus point and maintained in the isothermal conditions at three different temperatures (560, 580 and 595 °C) for varying time (5, 10, 20 and 40 min). The microstructural study was carried out on the alloy by the use of optical microscopy. It was observed that strain induced deformation and subsequently melt activation has caused the globular morphology of Mg₂Si particles. The results showed that for the desired microstructures of the alloy during SIMA process, the optimum temperature and time are 595 °C and 40 min respectively.Keywords: deformation, semisolid, SIMA, Mg₂Si phase, modification
Procedia PDF Downloads 2831195 Nematodes, Rotifers, Tardigrades and Diatoms as Vehicles for the Panspermic Transfer of Microbes
Authors: Sulamain Alharbi, Mohammad Khiyami, Reda Amasha, Bassam Al-Johny, Hesham Khalil, Milton Wainwrigh
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Nematodes, Rotifers and Tardigrades (NRT) are extreme-tolerant invertebrates which can survive long periods of stasis brought about by extreme drying and cold. They can also resist the effects of UV radiation, and as a result could act as vehicles for the panspermic transfer of microorganisms. Here we show that NRT contain a variety of bacteria and fungi within their bodies in which environment they could be protected from the extremes of the space and released into new cosmic environments. Diatoms were also shown to contain viable alga and Escherichia coli and so could also act as panspermic vehicles for the transfer of these and perhaps other microbes through space. Although not studied here, NRT, and possibly diatoms, also carry protozoa and viruses within their bodies and could act as vehicles for the panspermic transfer of an even wider range of microbes than shown here.Keywords: extromophiles, diatoms, panspermia, survival in space
Procedia PDF Downloads 5601194 The Appropriate Patent System to Promote Economic Growth in Afghanistan
Authors: Mohammad Reza Fooladi
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The patent system which fits with industrial and economic situation in the country, by strengthening research and development, technology transfer and increasing foreign investment can provide economic and industrial growth of the countries. However, the extent and manner of support should be commensurate with the country's conditions and comply with significant rules to have a positive effect on research and development, technology transfer and the amount of foreign investment. The present article tries to while reviewing the state of effectiveness of the patent system on economic growth, to illustrate the characteristics of the patent system fits Afghanistan and according to this matter provide the necessary recommendations about the improvement of laws and regulations related to the patent in Afghanistan.Keywords: patent, economic growth, technology transfer, Afghanistan
Procedia PDF Downloads 4121193 DNA Multiplier: A Design Architecture of a Multiplier Circuit Using DNA Molecules
Authors: Hafiz Md. Hasan Babu, Khandaker Mohammad Mohi Uddin, Nitish Biswas, Sarreha Tasmin Rikta, Nuzmul Hossain Nahid
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Nanomedicine and bioengineering use biological systems that can perform computing operations. In a biocomputational circuit, different types of biomolecules and DNA (Deoxyribose Nucleic Acid) are used as active components. DNA computing has the capability of performing parallel processing and a large storage capacity that makes it diverse from other computing systems. In most processors, the multiplier is treated as a core hardware block, and multiplication is one of the time-consuming and lengthy tasks. In this paper, cost-effective DNA multipliers are designed using algorithms of molecular DNA operations with respect to conventional ones. The speed and storage capacity of a DNA multiplier are also much higher than a traditional silicon-based multiplier.Keywords: biological systems, DNA multiplier, large storage, parallel processing
Procedia PDF Downloads 2181192 The Relationship between Organizational Culture and the Establishment of Knowledge Management in the Central Insurance of Iran
Authors: Alireza Assareh, Fatemeh Havas Beigi, Mohammad Vafaee Yeganeh
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The present study is conducted to investigate the relationship between organizational culture and the establishment of knowledge management in the Central Insurance of Iran. The research results revealed that there is a significant positive relationship between organizational culture and its elements that include management support, organizational belonging, individual innovation, and leadership style and the establishment of knowledge management in the central insurance of Iran and that there isn’t any significant relationship between conflict resolution and the establishment of knowledge management in the central insurance of Iran.Keywords: organizational culture, knowledge management, central insurance of Iran, individual innovation
Procedia PDF Downloads 4921191 Prediction of a Nanostructure Called Porphyrin-Like Buckyball, Using Density Functional Theory and Investigating Electro Catalytic Reduction of Co₂ to Co by Cobalt– Porphyrin-Like Buckyball
Authors: Mohammad Asadpour, Maryam Sadeghi, Mahmoud Jafari
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The transformation of carbon dioxide into fuels and commodity chemicals is considered one of the most attractive methods to meet energy demands and reduce atmospheric CO₂ levels. Cobalt complexes have previously shown high faradaic efficiency in the reduction of CO₂ to CO. In this study, a nanostructure, referred to as a porphyrin-like buckyball, is simulated and analyzed for its electrical properties. The investigation aims to understand the unique characteristics of this material and its potential applications in electronic devices. Through computational simulations and analysis, the electrocatalytic reduction of CO₂ to CO by Cobalt-porphyrin-like buckyball is explored. The findings of this study offer valuable insights into the electrocatalytic properties of this predicted structure, paving the way for further research and development in the field of nanotechnology.Keywords: porphyrin-like buckyball, DFT, nanomaterials, CO₂ to CO
Procedia PDF Downloads 541190 Opto-Electronic Properties of Novel Structures: Sila-Fulleranes
Authors: Farah Marsusi, Mohammad Qasemnazhand
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Density-functional theory (DFT) was applied to investigate the geometry and electronic properties H-terminated Si-fullerene (Si-fullerane). Natural bond orbital (NBO) analysis confirms sp3 hybridization nature of Si-Si bonds in Si-fulleranes. Quantum confinement effect (QCE) does not affect band gap (BG) so strongly in the size between 1 to 1.7 nm. In contrast, the geometry and symmetry of the cage have significant influence on BG. In contrast to their carbon analogues, pentagon rings increase the stability of the cages. Functionalized Si-cages are stable and can be chemically very active. The electronic properties are highly sensitive to the surface chemistry via functionalization with different chemical groups. As a result, BGs and chemical activities of these cages can be drastically tuned through the chemistry of the surface.Keywords: density functional theory, sila-fullerens, NBO analysis, opto-electronic properties
Procedia PDF Downloads 2991189 Forster Energy Transfer and Optoelectronic Properties of (PFO/TiO2)/Fluorol 7GA Hybrid Thin Films
Authors: Bandar Ali Al-Asbahi, Mohammad Hafizuddin Haji Jumali
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Forster energy transfer between poly (9,9'-di-n-octylfluorenyl-2,7-diyl) (PFO)/TiO2 nanoparticles (NPs) as a donor and Fluorol 7GA as an acceptor has been studied. The energy transfer parameters were calculated by using mathematical models. The dominant mechanism responsible for the energy transfer between the donor and acceptor molecules was Forster-type, as evidenced by large values of quenching rate constant, energy transfer rate constant and critical distance of energy transfer. Moreover, these composites which were used as an emissive layer in organic light emitting diodes, were investigated in terms of current density–voltage and electroluminescence spectra.Keywords: energy transfer parameters, forster-type, electroluminescence, organic light emitting diodes
Procedia PDF Downloads 4281188 Fabricating Anti-Counterfeiting Films by Grafting Cationic Dye on Cellulose Nanofiber
Authors: Mohammadreza Biabani, Mohammad Azadfallah
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A facile and robust strategy is required to fabricate films with high special optical properties for application in the field of anti-counterfeit marking. Nanocellulose, derived from bioresources, is a renewable material with broad application prospects. In this paper, a method for grafting the eco-friendly Berberine cationic dye on cellulose nanofiber is proposed. A functional modification was carried out by in-situ polymerization along with a grafting approach with acrylic acid(AA) in order to develop cationic dyeability of the cellulose nanofiber (CNF). The Berberine grafting on nanocellulose was significantly influenced by the reaction time and temperature during the dyeing process. The dyed CNF-films exhibited appropriate characteristics like appearance, color strength, and fastness for anti-counterfeiting application.Keywords: Cellulose nanofiber, Berberine, Grafting, anti-counterfeiting, film
Procedia PDF Downloads 1321187 Self-Reliant and Auto-Directed Learning: Modes, Elements, Fields and Scopes
Authors: Habibollah Mashhady, Behruz Lotfi, Mohammad Doosti, Moslem Fatollahi
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An exploration of the related literature reveals that all instruction methods aim at training autonomous learners. After the turn of second language pedagogy toward learner-oriented strategies, learners’ needs were more focused. Yet; the historical, social and political aspects of learning were still neglected. The present study investigates the notion of autonomous learning and explains its various facets from a pedagogical point of view. Furthermore; different elements, fields and scopes of autonomous learning will be explored. After exploring different aspects of autonomy, it is postulated that liberatory autonomy is highlighted since it not only covers social autonomy but also reveals learners’ capabilities and human potentials. It is also recommended that learners consider different elements of autonomy such as motivation, knowledge, confidence, and skills.Keywords: critical pedagogy, social autonomy, academic learning, cultural notions
Procedia PDF Downloads 461