Search results for: multi variable decision making
2491 TA6V Selective Laser Melting as an Innovative Method Produce Complex Shapes
Authors: Rafał Kamiński, Joel Rech, Philippe Bertrand, Christophe Desrayaud
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Additive manufacturing is a hot topic for industry. Among the additive techniques, Selective Laser Melting (SLM) becomes even more popular, especially for making parts for aerospace applications, thanks to its design freedom (customized and light structures) and its reduced time to market. However, some functional surfaces have to be machined to achieve small tolerances and low surface roughness to fulfill industry specifications. The complex shapes designed for SLM (ex: titanium turbine blades) necessitate the use of ball end milling operations like in the conventional process after forging. However, the metallurgical state of TA6V is very different from the one obtained usually from forging, because of the laser sintering layer by layer. So this paper aims to investigate the influence of new TA6V metallurgies produced by SLM on the machinability in ball end milling. Machinability is considered as the property of a material to obtain easily and by a cheap way a functional surface. This means, for instance, the property to limit cutting tool wear rate and to get smooth surfaces. So as to reach this objective, SLM parts have been produced and heat treated with various conditions leading to various metallurgies that are compared with a standard equiaxed α+β wrought microstructure. The machinability is analyzed by measuring surface roughness, tool wear and cutting forces for a range of cutting conditions (depth of cut 'ap', feed per tooth 'fz', spindle speed 'N') in accordance with industrial practices. This work has revealed that TA6V produced by SLM can lead to a better machinability that standard wrought alloys.Keywords: ball milling, selective laser melting, surface roughness, titanium, wear
Procedia PDF Downloads 2842490 Iris Recognition Based on the Low Order Norms of Gradient Components
Authors: Iman A. Saad, Loay E. George
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Iris pattern is an important biological feature of human body; it becomes very hot topic in both research and practical applications. In this paper, an algorithm is proposed for iris recognition and a simple, efficient and fast method is introduced to extract a set of discriminatory features using first order gradient operator applied on grayscale images. The gradient based features are robust, up to certain extents, against the variations may occur in contrast or brightness of iris image samples; the variations are mostly occur due lightening differences and camera changes. At first, the iris region is located, after that it is remapped to a rectangular area of size 360x60 pixels. Also, a new method is proposed for detecting eyelash and eyelid points; it depends on making image statistical analysis, to mark the eyelash and eyelid as a noise points. In order to cover the features localization (variation), the rectangular iris image is partitioned into N overlapped sub-images (blocks); then from each block a set of different average directional gradient densities values is calculated to be used as texture features vector. The applied gradient operators are taken along the horizontal, vertical and diagonal directions. The low order norms of gradient components were used to establish the feature vector. Euclidean distance based classifier was used as a matching metric for determining the degree of similarity between the features vector extracted from the tested iris image and template features vectors stored in the database. Experimental tests were performed using 2639 iris images from CASIA V4-Interival database, the attained recognition accuracy has reached up to 99.92%.Keywords: iris recognition, contrast stretching, gradient features, texture features, Euclidean metric
Procedia PDF Downloads 3382489 Beliefs about the Use of Extemporaneous Compounding for Paediatric Outpatients among Physicians in Yogyakarta, Indonesia
Authors: Chairun Wiedyaningsih, Sri Suryawati, Yati Soenarto, Muhammad Hakimi
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Background: Many drugs used in paediatrics are not commercially available in suitable dosage forms. Therefore, the drugs often prescribed in extemporaneous compounding dosage form. Compounding can pose health risks include poor quality and unsafe products. Studies of compounding dosage form have primarily focused on prescription profiles, reasons of prescribing never be explored. Objectives: The study was conducted to identify factors influencing physicians’ decision to prescribe extemporaneous compounding dosage form for paediatric outpatients. Setting: Daerah Istimewa Yogyakarta (DIY) province, Indonesia. Method: Qualitative semi-structured interviews were conducted with 15 general physicians and 7 paediatricians to identify the reason of prescribing extemporaneous compounding dosage form. The interviews were transcribed and analysed using thematic analysis. Results: Factors underlying prescribing of compounding could be categorized to therapy, healthcare system, patient and past experience. The primary reasons of therapy factors were limited availability of drug compositions, dosages or formulas specific for children. Beliefs in efficacy of the compounding forms were higher when the drugs used primarily to overcome complex cases. Physicians did not concern about compounding form containing several active substances because manufactured syrups may also contain several active substances. Although medicines were available in manufactured syrups, limited institutional budget was healthcare system factor of compounding prescribing. The prescribing factors related to patients include easy to use, efficient and lower price. The prescribing factors related to past experience were physicians’ beliefs to the progress of patient's health status. Conclusions: Compounding was prescribed based on therapy-related factors, healthcare system factors, patient factors and past experience.Keywords: compounding dosage form, interview, physician, prescription
Procedia PDF Downloads 4342488 Evaluation of the Causes of Exposure to Mobbing of Employees in the Public Sector in Turkey
Authors: Taner Cindik, Ferya Tas Ciftci
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Mobbing in the public sector and specific issues (i.e., the demand for non-pecuniary damages) regarding mobbing have become very important in the light of the precedents constituted by the Turkish Council of State in 2010. The legal scope of mobbing is not able to be determined since the concept of mobbing is not defined in Turkish law system. This study aims to reveal three major problems caused by the lack of laws related to mobbing in the Turkish legal system. First, the absence of an arrangement for disciplinary penalties leads that general provisions in the disciplinary law are implemented. This situation, therefore, causes difficulties in practice. Second, not being drawn of the lines in the topic concerning mobbing in public sector leads confusions in being direction of hostility. Third, the fact that there is a legal gap on seeking non-pecuniary compensation when employees in public sector are exposed to mobbing might make it difficult to obtain non-pecuniary compensation. Within the context of these major problems, civil servants in Turkey do not have enough protection mechanism. However, some possible legal arrangements will help civil servants to protect against mobbing. This study may be considered important because of the fact that mobbing in the public sector is at a significant level and has not been evaluated in this context before. This research is mainly a study of Turkish legal system and evaluates critically law case to determine legal problems. As a result of this study, three main problems might be identified because there is legal gap regarding mobbing in the public sector. In conclusion, the introduction of the major problems related to mobbing in this study might shed light on making the proper regulations of this subject in Turkish law system. In this respect, the plaintiff will be provided convenience in the point of non-pecuniary damages and this study will guide the assessment of legal liability of those who implement mobbing.Keywords: human rights violations, mobbing, public sector, direction of hostility, non-pecuniary compensation, disciplinary law
Procedia PDF Downloads 2472487 River Network Delineation from Sentinel 1 Synthetic Aperture Radar Data
Authors: Christopher B. Obida, George A. Blackburn, James D. Whyatt, Kirk T. Semple
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In many regions of the world, especially in developing countries, river network data are outdated or completely absent, yet such information is critical for supporting important functions such as flood mitigation efforts, land use and transportation planning, and the management of water resources. In this study, a method was developed for delineating river networks using Sentinel 1 imagery. Unsupervised classification was applied to multi-temporal Sentinel 1 data to discriminate water bodies from other land covers then the outputs were combined to generate a single persistent water bodies product. A thinning algorithm was then used to delineate river centre lines, which were converted into vector features and built into a topologically structured geometric network. The complex river system of the Niger Delta was used to compare the performance of the Sentinel-based method against alternative freely available water body products from United States Geological Survey, European Space Agency and OpenStreetMap and a river network derived from a Shuttle Rader Topography Mission Digital Elevation Model. From both raster-based and vector-based accuracy assessments, it was found that the Sentinel-based river network products were superior to the comparator data sets by a substantial margin. The geometric river network that was constructed permitted a flow routing analysis which is important for a variety of environmental management and planning applications. The extracted network will potentially be applied for modelling dispersion of hydrocarbon pollutants in Ogoniland, a part of the Niger Delta. The approach developed in this study holds considerable potential for generating up to date, detailed river network data for the many countries where such data are deficient.Keywords: Sentinel 1, image processing, river delineation, large scale mapping, data comparison, geometric network
Procedia PDF Downloads 1432486 GIS Mapping of Sheep Population and Distribution Pattern in the Derived Savannah of Nigeria
Authors: Sosina Adedayo O., Babyemi Olaniyi J.
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The location, population, and distribution pattern of sheep are severe challenges to agribusiness investment and policy formulation in the livestock industry. There is a significant disconnect between farmers' needs and the policy framework towards ameliorating the sheep production constraints. Information on the population, production, and distribution pattern of sheep remains very scanty. A multi-stage sampling technique was used to elicit information from 180 purposively selected respondents from the study area comprised of Oluyole, Ona-ara, Akinyele, Egbeda, Ido and Ibarapa East LGA. The Global Positioning Systems (GPS) of the farmers' location (distribution), and average sheep herd size (Total Livestock Unit, TLU) (population) were recorded, taking the longitude and latitude of the locations in question. The recorded GPS data of the study area were transferred into the ARC-GIS. The ARC-GIS software processed the data using the ARC-GIS model 10.0. Sheep production and distribution (TLU) ranged from 4.1 (Oluyole) to 25.0 (Ibarapa East), with Oluyole, Akinyele, Ona-ara and Egbeda having TLU of 5, 7, 8 and 20, respectively. The herd sizes were classified as less than 8 (smallholders), 9-25 (medium), 26-50 (large), and above 50 (commercial). The majority (45%) of farmers were smallholders. The FR CP (%) ranged from 5.81±0.26 (cassava leaf) to 24.91±0.91 (Amaranthus spinosus), NDF (%) ranged from 22.38±4.43 (Amaranthus spinosus) to 67.96 ± 2.58 (Althemanthe dedentata) while ME ranged from 7.88±0.24 (Althemanthe dedentata) to 10.68±0.18 (cassava leaf). The smallholders’ sheep farmers were the majority, evenly distributed across rural areas due to the availability of abundant feed resources (crop residues, tree crops, shrubs, natural pastures, and feed ingredients) coupled with a large expanse of land in the study area. Most feed resources available were below sheep protein requirement level, hence supplementation is necessary for productivity. Bio-informatics can provide relevant information for sheep production for policy framework and intervention strategies.Keywords: sheep enterprise, agribusiness investment, policy, bio-informatics, ecological zone
Procedia PDF Downloads 902485 Impact of Information Technology Systems on the Recruitment Process in Morocco
Authors: Brahim Bellali, Fatima Bellali
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The integration of information technology systems (ITS) into a company's ‘human resources processes seems to be the appropriate solution to the problem of evolving and adapting its human resources management practices in order to be both more strategic and more efficient in terms of costs and service quality. In this context, the aim of this work is to study the impact of information technology systems (ITS) on the recruitment process. In this study, we targeted candidates who had recruited using IT tools. The target population consists of 34 candidates based in Casablanca, Morocco. In order to collect the data, a questionnaire had to be drawn up. The survey is based on a data sheet and a questionnaire that is divided into several sections to make it more structured and comprehensible. The results show that the majority of respondents say that companies are making greater use of online CV libraries and social networks as digital solutions during the recruitment process. The results also show that 50% of candidates say that the use of digital tools by companies would not slow them down when applying for a job and that these IT tools improve manual recruitment processes, while 44.1% think that they facilitate recruitment without any human intervention. The majority of respondents (52.9%) think that social networks are the digital solutions most often used by recruiters in the sourcing phase. The constraints of digital recruitment encountered are the dehumanization of human resources (44.1%) and the limited interaction during remote interviews (44.1%), which leaves no room for informal exchanges. Digital recruitment can be a highly effective strategy for finding qualified candidates in a variety of fields. Here are a few recommendations for optimizing your digital recruitment process: (1) Use online recruitment platforms: LinkedIn, Twitter, and Facebook ; (2) Use applicant tracking systems (ATS) ; (3) Develop a content marketing strategy.Keywords: IT systems, recruitment, challenges, constraints
Procedia PDF Downloads 172484 Impact of Entrepreneurship Education on Entrepreneurial Intention: A Case Study of Al Akhawayn University
Authors: Sara atibi, Azzeddine Atibi, Salim Ahmed, Khadija El Kababi
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Given the crucial impact of entrepreneurship on socio-economic development, nations are making various efforts to support and encourage it. Entrepreneurship education has proven to be a vital lever in stimulating business creation. This research is part of this dynamic, which is increasingly attracting the attention of educational policymakers. Indeed, entrepreneurship education provides students with the skills, knowledge, and motivation needed to succeed in various entrepreneurial contexts. it objective is to demonstrate the impact of entrepreneurship education on the development of entrepreneurial intention among students at Al Akhawayn University and to determine whether introducing this discipline at the secondary school level can strengthen this intention, with the aim of proposing measures to foster entrepreneurship. To achieve this objective, it conducted a literature review on entrepreneurship, entrepreneurial intention, and entrepreneurship education to draw from existing experiences in the field. it then carried out an exploratory study through a qualitative survey. it collected real data via an online questionnaire hosted on Google Drive. This questionnaire was tested on a sample of 100 students, adjusted, and validated by three university professors who are experts in the field, and then administered to the students of Al Akhawayn University. The results of our survey among students at Al Akhawayn University clearly show that the development of entrepreneurial intention increases among students who have taken entrepreneurship courses or participated in seminars, thus promoting business creation and entrepreneurship. A minority of these students still choose to work in the private or public sector; however, the majority express a strong desire to become entrepreneurs. We also noted that some students believe entrepreneurship depends solely on entrepreneurial training, while others think it relies on a combination of training, resources, and personal will.Keywords: entrepreneurship education, entrepreneurial intention, business creation, al akhawayn university, secondary school curriculum
Procedia PDF Downloads 402483 Enhanced Disk-Based Databases towards Improved Hybrid in-Memory Systems
Authors: Samuel Kaspi, Sitalakshmi Venkatraman
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In-memory database systems are becoming popular due to the availability and affordability of sufficiently large RAM and processors in modern high-end servers with the capacity to manage large in-memory database transactions. While fast and reliable in-memory systems are still being developed to overcome cache misses, CPU/IO bottlenecks and distributed transaction costs, disk-based data stores still serve as the primary persistence. In addition, with the recent growth in multi-tenancy cloud applications and associated security concerns, many organisations consider the trade-offs and continue to require fast and reliable transaction processing of disk-based database systems as an available choice. For these organizations, the only way of increasing throughput is by improving the performance of disk-based concurrency control. This warrants a hybrid database system with the ability to selectively apply an enhanced disk-based data management within the context of in-memory systems that would help improve overall throughput. The general view is that in-memory systems substantially outperform disk-based systems. We question this assumption and examine how a modified variation of access invariance that we call enhanced memory access, (EMA) can be used to allow very high levels of concurrency in the pre-fetching of data in disk-based systems. We demonstrate how this prefetching in disk-based systems can yield close to in-memory performance, which paves the way for improved hybrid database systems. This paper proposes a novel EMA technique and presents a comparative study between disk-based EMA systems and in-memory systems running on hardware configurations of equivalent power in terms of the number of processors and their speeds. The results of the experiments conducted clearly substantiate that when used in conjunction with all concurrency control mechanisms, EMA can increase the throughput of disk-based systems to levels quite close to those achieved by in-memory system. The promising results of this work show that enhanced disk-based systems facilitate in improving hybrid data management within the broader context of in-memory systems.Keywords: in-memory database, disk-based system, hybrid database, concurrency control
Procedia PDF Downloads 4222482 Impact of Information Technology Systems on the Recruitment Process in Morocco
Authors: Bellali Brahim, Bellali Fatima
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The integration of information technology systems (ITS) into a company's ‘human resources processes seems to be the appropriate solution to the problem of evolving and adapting its human resources management practices in order to be both more strategic and more efficient in terms of costs and service quality. In this context, the aim of this work is to study the impact of nformation technology systems (ITS) on the recruitment process. In this study, we targeted candidates who had recruited using IT tools. The target population consists of 34 candidates based in Casablanca, Morocco. In order to collect the data, a questionnaire had to be drawn up. The survey is based on a data sheet and a questionnaire that is divided into several sections to make it more structured and comprehensible. The results show that the majority of respondents say that companies are making greater use of online CV libraries and social networks as digital solutions during the recruitment process. The results also show that 50% of candidates say that the use of digital tools by companies would not slow them down when applying for a job and that these IT tools improve manual recruitment processes, while 44.1% think that they facilitate recruitment without any human intervention. The majority of respondents (52.9%) think that social networks are the digital solutions most often used by recruiters in the sourcing phase. The constraints of digital recruitment encountered are the dehumanization of human resources (44.1%) and the limited interaction during remote interviews (44.1%), which leaves no room for informal exchanges. Digital recruitment can be a highly effective strategy for finding qualified candidates in a variety of fields. Here are a few recommendations for optimizing your digital recruitment process: (1) Use online recruitment platforms: LinkedIn, Twitter, and Facebook ; (2) Use applicant tracking systems (ATS) ; (3) Develop a content marketing strategy.Keywords: IT systems, recruitment, challenges, constraints
Procedia PDF Downloads 322481 Community-Based Reference Interval of Selected Clinical Chemistry Parameters Among Apparently Healthy Adolescents in Mekelle City, Tigrai, Northern Ethiopia
Authors: Getachew Belay Kassahun
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Background: Locally established clinical laboratory reference intervals (RIs) are required to interpret laboratory test results for screening, diagnosis, and prognosis. The objective of this study was to establish a reference interval of clinical chemistry parameters among apparently healthy adolescents aged between 12 and 17 years in Mekelle, Tigrai, in the northern part of Ethiopia. Methods: Community-based cross-sectional study was employed from December 2018 to March 2019 in Mekelle City among 172 males and 172 females based on a Multi-stage sampling technique. Blood samples were tested for Fasting blood sugar (FBS), alanine amino transferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), Creatinine, urea, total protein, albumin (ALB), direct and indirect bilirubin (BIL.D and BIL.T) using 25 Bio system clinical chemistry analyzer. Results were analyzed using SPSS version 23 software and based on the Clinical Laboratory Standard Institute (CLSI)/ International Federation of Clinical Chemistry (IFCC) C 28-A3 Guideline which defines the reference interval as the 95% central range of 2.5th and 97.5th percentiles. Mann Whitney U test, descriptive statistics and box and whisker were statistical tools used for analysis. Results: This study observed statistically significant differences between males and females in ALP, ALT, AST, Urea and Creatinine Reference intervals. The established reference intervals for males and females, respectively, were: ALP (U/L) 79.48-492.12 versus 63.56-253.34, ALT (U/L) 4.54-23.69 versus 5.1-20.03, AST 15.7- 39.1 versus 13.3- 28.5, Urea (mg/dL) 9.33-24.99 versus 7.43-23.11, and Creatinine (mg/dL) 0.393-0.957 versus 0.301-0.846. The combined RIs for Total Protein (g/dL) were 6.08-7.85, ALB (g/dL) 4.42-5.46, FBS(mg/dL) 65-110, BIL.D (mg/dL) 0.033-0.532, and BIL.T (mg/dL) 0.106-0.812. Conclusions: The result showed a marked difference between sex and company-derived values for selected clinical chemistry parameters. Thus, the use of age and sex-specific locally established reference intervals for clinical chemistry parameters is recommended.Keywords: reference interval, adolescent, clinical chemistry, Ethiopia
Procedia PDF Downloads 852480 Low-Cost Parking Lot Mapping and Localization for Home Zone Parking Pilot
Authors: Hongbo Zhang, Xinlu Tang, Jiangwei Li, Chi Yan
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Home zone parking pilot (HPP) is a fast-growing segment in low-speed autonomous driving applications. It requires the car automatically cruise around a parking lot and park itself in a range of up to 100 meters inside a recurrent home/office parking lot, which requires precise parking lot mapping and localization solution. Although Lidar is ideal for SLAM, the car OEMs favor a low-cost fish-eye camera based visual SLAM approach. Recent approaches have employed segmentation models to extract semantic features and improve mapping accuracy, but these AI models are memory unfriendly and computationally expensive, making deploying on embedded ADAS systems difficult. To address this issue, we proposed a new method that utilizes object detection models to extract robust and accurate parking lot features. The proposed method could reduce computational costs while maintaining high accuracy. Once combined with vehicles’ wheel-pulse information, the system could construct maps and locate the vehicle in real-time. This article will discuss in detail (1) the fish-eye based Around View Monitoring (AVM) with transparent chassis images as the inputs, (2) an Object Detection (OD) based feature point extraction algorithm to generate point cloud, (3) a low computational parking lot mapping algorithm and (4) the real-time localization algorithm. At last, we will demonstrate the experiment results with an embedded ADAS system installed on a real car in the underground parking lot.Keywords: ADAS, home zone parking pilot, object detection, visual SLAM
Procedia PDF Downloads 722479 Relationship Financing: A Process of Interpretative Phenomenological Analysis
Authors: Y. Fandja, O. Colot, M. Croquet
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Small and medium-sized firms (SMEs) face difficulties in accessing bank credit. Bank credit is actually the main source of external financing for SMEs. In general, SMEs are risky businesses because of the potential opacity maintained by the leader in the management of affairs, the agency conflicts between business owners and third-party funders and the potential opportunism of the leader due to the incompleteness of the contracts. These elements accentuate the problems of information asymmetries between SMEs and bankers leading to capital rationing. Moreover, the last economic crisis reinforced this rationing of capital. However, a long-term relationship between SMEs and their bank would enable the latter to accumulate a set of relevant information allowing the reduction of information asymmetry and, consequently, the reduction of credit rationing. The objective of this research is to investigate the lived experience of SMEs loan officers in their relationships with their clients in order to understand how these relationships can affect the financing structure of these SMEs. To carry out this research, an Interpretative Phenomenological Analysis is implemented. This approach is part of the constructivist paradigm and refers to the subjective narratives of the individual rather than to an objective description of the facts. The role of the researcher is to explore the lived experience of the interviewees and to try to understand the meaning they give to this experience. Currently, several sixty-minute semi-structured interviews with loan officers for SMEs have been conducted. The analysis of the content of these interviews brought out three main themes. First, the relationship between the credit officer and the company manager is complex because the credit officer is not aware of establishing a personal relationship with his client. Second; the emotional involvement in the bank financing decision is present and third, the trust in the relationship between the credit officer and his client is very important. The originality of this research is to use the interpretative phenomenological analysis more specific to psychology and sociology in order to approach in a different way the problem of the financing of SMEs through their particular relations with the bankers.Keywords: financing structure, interpretative phenomenological analysis, relationship financing, SME
Procedia PDF Downloads 1612478 E4D-MP: Time-Lapse Multiphysics Simulation and Joint Inversion Toolset for Large-Scale Subsurface Imaging
Authors: Zhuanfang Fred Zhang, Tim C. Johnson, Yilin Fang, Chris E. Strickland
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A variety of geophysical techniques are available to image the opaque subsurface with little or no contact with the soil. It is common to conduct time-lapse surveys of different types for a given site for improved results of subsurface imaging. Regardless of the chosen survey methods, it is often a challenge to process the massive amount of survey data. The currently available software applications are generally based on the one-dimensional assumption for a desktop personal computer. Hence, they are usually incapable of imaging the three-dimensional (3D) processes/variables in the subsurface of reasonable spatial scales; the maximum amount of data that can be inverted simultaneously is often very small due to the capability limitation of personal computers. Presently, high-performance or integrating software that enables real-time integration of multi-process geophysical methods is needed. E4D-MP enables the integration and inversion of time-lapsed large-scale data surveys from geophysical methods. Using the supercomputing capability and parallel computation algorithm, E4D-MP is capable of processing data across vast spatiotemporal scales and in near real time. The main code and the modules of E4D-MP for inverting individual or combined data sets of time-lapse 3D electrical resistivity, spectral induced polarization, and gravity surveys have been developed and demonstrated for sub-surface imaging. E4D-MP provides capability of imaging the processes (e.g., liquid or gas flow, solute transport, cavity development) and subsurface properties (e.g., rock/soil density, conductivity) critical for successful control of environmental engineering related efforts such as environmental remediation, carbon sequestration, geothermal exploration, and mine land reclamation, among others.Keywords: gravity survey, high-performance computing, sub-surface monitoring, electrical resistivity tomography
Procedia PDF Downloads 1612477 Deuterium Effect on the Growth of the Fungus Aspergillus Fumigatus and Candida Albicans
Authors: Farzad Doostishoar, Abdolreza Hasanzadeh, Seyed Amin Ayatolahi Mousavi
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Introduction and Goals: Deuterium has different action from its isotopes hydrogen in chemical reactions and biochemical processes. It is not a significant difference in heavier atoms between the behavior of heavier isotope and the lighter One but for very lighter atoms it is significant . According to that most of the weight of all creatures body is water natural rate can be significant. In this article we want to study the effect of reduced deuterium on the fungus cell. If we saw the dependence of deuterium concentration of environment on the cells growth we can test this in invivo models too. Methods: First we measured deuterium concentration of the distillated water this analyze was operated by Arak’s heavy water company. Then the deuterium was diluted to ½ ¼ 1/8 1/16 by adding water free of deuterium for making media. In tree of samples the deuterium concentration was increased by adding D2O up to 10,50,100 times more concentrated. For candida albicans growth we used sabor medium and for aspergillus fomigatis growth we used sabor medium containing chloramphenicol. After culturing the funguses species we put the mediums for each species in the shaker incubator for 10 days in 25 centigrade. In different days and times the plates were studied morphologically and some microscopic characteristics were studied too. This experiments and cultures were repeated 3 times. Results: Statistical analyzes by paired-sample T test showed that aspergilus fomigatoos growth was decreased in concentration of 72 ppm( half deuterium concentration of negative control) significantly. In deuterium concentration reduction the growth reduce into the negative control significantly. The project results showed that candida albicans was sensitive to reduce and decrease of the deuterium in all concentrations.Keywords: deuterium, cancer cell, growth, candida albicans
Procedia PDF Downloads 4042476 Roll Forming Process and Die Design for a Large Size Square Tube
Authors: Jinn-Jong Sheu, Cang-Fu Liang, Cheng-Hsien Yu
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This paper proposed the cold roll forming process and the die design methods for a 400mm by 400 mm square tube with 16 mm in thickness. The tubular blank made by cold roll forming is 508mm in diameter. The square tube roll forming process was designed considering the layout of rolls and the compression ratio distribution for each stand. The final tube corner radius and the edge straightness in the front end of the tube are to be controlled according to the tube specification. A five-stand forming design using four rolls at each stand was proposed to establish the base reference of square tube roll forming quality. Different numbers of pass and roll designs were proposed and compared to the base design in order to find the feasibility of increase pass number to improve the square tube quality. The proposed roll forming processes were simulated using FEM analysis. The thickness variations of the corner and the edge areas were examined. The maximum loads and the torques of each stand were calculated to study the power consumption of the roll forming machine. The simulation results showed the square tube thickness variations and concavity of the edge are acceptable with the JIS tube specifications for the base design. But the maximum loads and torques are very high. By changing the layout and the number of the rolls were able to obtain better tube geometry and decrease the maximum load and torque of each stand. This paper had shown the feasibility of designing the roll forming process and the layout of dies using FEM simulation. The obtained information is helpful to the roll forming machine design for a large size square tube making.Keywords: cold roll forming, FEM analysis, roll forming die design, tube roll forming
Procedia PDF Downloads 3172475 Enhancing Embedded System Efficiency with Digital Signal Processing Cores
Authors: Anil Dhanawade, Akshay S., Harshal Lakesar
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This paper presents a comprehensive analysis of the performance advantages offered by DSP (Digital Signal Processing) cores compared to traditional MCU (Microcontroller Unit) cores in the execution of various functions critical to real-time applications. The focus is on the integration of DSP functionalities, specifically in the context of motor control applications such as Field-Oriented Control (FOC), trigonometric calculations, back-EMF estimation, digital filtering, and high-resolution PWM generation. Through comparative analysis, it is demonstrated that DSP cores significantly enhance processing efficiency, achieving faster execution times for complex mathematical operations essential for precise torque and speed control. The study highlights the capabilities of DSP cores, including single-cycle Multiply-Accumulate (MAC) operations and optimized hardware for trigonometric functions, which collectively reduce latency and improve real-time performance. In contrast, MCU cores, while capable of performing similar tasks, typically exhibit longer execution times due to reliance on software-based solutions and lack of dedicated hardware acceleration. The findings underscore the critical role of DSP cores in applications requiring high-speed processing and low-latency response, making them indispensable in automotive, industrial, and robotics sectors. This work serves as a reference for future developments in embedded systems, emphasizing the importance of architecture choice in achieving optimal performance in demanding computational tasks.Keywords: assembly code, DSP core, instruction set, MCU core
Procedia PDF Downloads 252474 Correlates of Modes of Transportation to Work among Working Adults in Ernakulam District, Kerala
Authors: Anjaly Joseph, Elezebeth Mathews
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Transportation and urban planning is the least recognised area for physical activity promotion in India, unlike developed regions. Identifying the preferred transportation modalities and factors associated with it is essential to address these lacunae. The objective of the study was to assess the prevalence of modes of transportation to work, and its correlates among working adults in Ernakulam District, Kerala. A cross sectional study was conducted among 350 working individuals in the age group of 18-60 years, selected through multi-staged stratified random sampling in Ernakulam district of Kerala. The inclusion criteria were working individuals 18-60 years, workplace at a distance of more than 1 km from the home and who worked five or more days a week. Pregnant women/women on maternity leave and drivers (taxi drivers, autorickshaw drivers, and lorry drivers) were excluded. An interview schedule was used to capture the modes of transportation namely, public, private and active transportation, socio demographic details, travel behaviour, anthropometric measurements and health status. Nearly two-thirds (64 percent) of them used private transportation to work, while active commuters were only 6.6 percent. The correlates identified for active commuting compared to other modes were low socio-economic status (OR=0.22, CI=0.5-0.85) and presence of a driving license (OR=4.95, CI= 1.59-15.45). The correlates identified for public transportation compared to private transportation were female gender (OR= 17.79, CI= 6.26-50.31), low income (OR=0.33, CI= 0.11-0.93), being unmarried (OR=5.19, CI=1.46-8.37), presence of no or only one private vehicle in the house (OR=4.23, CI=1.24-20.54) and presence of convenient public transportation facility to workplace (OR=3.97, CI= 1.66-9.47). The association between body mass index (BMI) and public transportation were explored and found that public transport users had lesser BMI than private commuters (OR=2.30, CI=1.23-4.29). Policies that encourage active and public transportation needs to be introduced such as discouraging private vehicle through taxes, introduction of convenient and safe public transportation facility, walking/cycling paths, and paid parking facility.Keywords: active transportation, correlates, India, public transportation, transportation modes
Procedia PDF Downloads 1702473 Development of Liquefaction-Induced Ground Damage Maps for the Wairau Plains, New Zealand
Authors: Omer Altaf, Liam Wotherspoon, Rolando Orense
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The Wairau Plains are located in the north-east of the South Island of New Zealand in the region of Marlborough. The region is cut by many active crustal faults such as the Wairau, Awatere, and Clarence faults, which give rise to frequent seismic events. This paper presents the preliminary results of the overall project in which liquefaction-induced ground damage maps are developed in the Wairau Plains based on the Ministry of Business, Innovation and Employment NZ guidance. A suite of maps has been developed in relation to the level of details that was available to inform the liquefaction hazard mapping. Maps at the coarsest level of detail make use of regional geologic information, applying semi-quantitative criteria based on geological age, design peak ground accelerations and depth to the water table. The next level of detail incorporates higher resolution surface geomorphologic characteristics to better delineate potentially liquefiable and non-liquefiable deposits across the region. The most detailed assessment utilised CPT sounding data to develop ground damage response curves for areas across the region and provide a finer level of categorisation of liquefaction vulnerability. Linking these with design level earthquakes defined through NZGS guidelines will enable detailed classification to be carried out at CPT investigation locations, from very low through to high liquefaction vulnerability. To update classifications to these detailed levels, CPT investigations in geomorphic regions are grouped together to provide an indication of the representative performance of the soils in these areas making use of the geomorphic mapping outlined above.Keywords: hazard, liquefaction, mapping, seismicity
Procedia PDF Downloads 1422472 Mnemotopic Perspectives: Communication Design as Stabilizer for the Memory of Places
Authors: C. Galasso
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The ancestral relationship between humans and geographical environment has long been at the center of an interdisciplinary dialogue, which sees one of its main research nodes in the relationship between memory and places. Given its deep complexity, this symbiotic connection continues to look for a proper definition that appears increasingly negotiated by different disciplines. Numerous fields of knowledge are involved, from anthropology to semiotics of space, from photography to architecture, up to subjects traditionally far from these reasonings. This is the case of Design of Communication, a young discipline, now confident in itself and its objectives, aimed at finding and investigating original forms of visualization and representation, between sedimented knowledge and new technologies. In particular, Design of Communication for the Territory offers an alternative perspective to the debate, encouraging the reactivation and reconstruction of the memory of places. Recognizing mnemotopes as a cultural object of vertical interpretation of the memory-place relationship, design can become a real mediator of the territorial fixation of memories, making them increasingly accessible and perceptible, contributing to build a topography of memory. According to a mnemotopic vision, Communication Design can support the passage from a memory in which the observer participates only as an individual to a collective form of memory. A mnemotopic form of Communication Design can, through geolocation and content map-based systems, make chronology a topography rooted in the territory and practicable; it can be useful to understand how the perception of the memory of places changes over time, considering how to insert them in the contemporary world. Mnemotopes can be materialized in different format of translation, editing and narration and then involved in complex systems of communication. The memory of places, therefore, if stabilized by the tools offered by Communication Design, can make visible ruins and territorial stratifications, illuminating them with new communicative interests that can be shared and participated.Keywords: memory of places, design of communication, territory, mnemotope, topography of memory
Procedia PDF Downloads 1372471 Third Eye: A Hybrid Portrayal of Visuospatial Attention through Eye Tracking Research and Modular Arithmetic
Authors: Shareefa Abdullah Al-Maqtari, Ruzaika Omar Basaree, Rafeah Legino
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A pictorial representation of hybrid forms in science-art collaboration has become a crucial issue in the course of exploring a new painting technique development. This is straight related to the reception of an invisible-recognition phenomenology. In hybrid pictorial representation of invisible-recognition phenomenology, the challenging issue is how to depict the pictorial features of indescribable objects from its mental source, modality and transparency. This paper proposes the hybrid technique of painting Demonstrate, Resemble, and Synthesize (DRS) through a combination of the hybrid aspect-recognition representation of understanding picture, demonstrative mod, the number theory, pattern in the modular arithmetic system, and the coherence theory of visual attention in the dynamic scenes representation. Multi-methods digital gaze data analyses, pattern-modular table operation design, and rotation parameter were used for the visualization. In the scientific processes, Eye-trackingvideo-sections based was conducted using Tobii T60 remote eye tracking hardware and TobiiStudioTM analysis software to collect and analyze the eye movements of ten participants when watching the video clip, Alexander Paulikevitch’s performance’s ‘Tajwal’. Results: we found that correlation of fixation count in section one was positively and moderately correlated with section two Person’s (r=.10, p < .05, 2-tailed) as well as in fixation duration Person’s (r=.10, p < .05, 2-tailed). However, a paired-samples t-test indicates that scores were significantly higher for the section one (M = 2.2, SD = .6) than for the section two (M = 1.93, SD = .6) t(9) = 2.44, p < .05, d = 0.87. In the visual process, the exported data of gaze number N was resembled the hybrid forms of visuospatial attention using the table-mod-analyses operation. The explored hybrid guideline was simply applicable, and it could be as alternative approach to the sustainability of contemporary visual arts.Keywords: science-art collaboration, hybrid forms, pictorial representation, visuospatial attention, modular arithmetic
Procedia PDF Downloads 3682470 Multiscale Hub: An Open-Source Framework for Practical Atomistic-To-Continuum Coupling
Authors: Masoud Safdari, Jacob Fish
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Despite vast amount of existing theoretical knowledge, the implementation of a universal multiscale modeling, analysis, and simulation software framework remains challenging. Existing multiscale software and solutions are often domain-specific, closed-source and mandate a high-level of experience and skills in both multiscale analysis and programming. Furthermore, tools currently existing for Atomistic-to-Continuum (AtC) multiscaling are developed with the assumptions such as accessibility of high-performance computing facilities to the users. These issues mentioned plus many other challenges have reduced the adoption of multiscale in academia and especially industry. In the current work, we introduce Multiscale Hub (MsHub), an effort towards making AtC more accessible through cloud services. As a joint effort between academia and industry, MsHub provides a universal web-enabled framework for practical multiscaling. Developed on top of universally acclaimed scientific programming language Python, the package currently provides an open-source, comprehensive, easy-to-use framework for AtC coupling. MsHub offers an easy to use interface to prominent molecular dynamics and multiphysics continuum mechanics packages such as LAMMPS and MFEM (a free, lightweight, scalable C++ library for finite element methods). In this work, we first report on the design philosophy of MsHub, challenges identified and issues faced regarding its implementation. MsHub takes the advantage of a comprehensive set of tools and algorithms developed for AtC that can be used for a variety of governing physics. We then briefly report key AtC algorithms implemented in MsHub. Finally, we conclude with a few examples illustrating the capabilities of the package and its future directions.Keywords: atomistic, continuum, coupling, multiscale
Procedia PDF Downloads 1792469 Integration of Technology through Instructional Systems Design
Authors: C. Salis, D. Zedda, M. F. Wilson
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The IDEA project was conceived for teachers who are interested in enhancing their capacity to effectively implement the use of specific technologies in their teaching practice. Participating teachers are coached and supported as they explore technologies applied to the educational context. They access tools such as the technological platform developed by our team. Among the platform functionalities, teachers access an instructional systems design (ISD) tool (learning designer) that was adapted to the needs of our project. The tool is accessible from computers or mobile devices and used in association with other technologies to create new, meaningful learning environments. The objective of an instructional systems design is to guarantee the quality and effectiveness of education and to enhance learning. This goal involves both teachers who want to become more efficient in transferring knowledge or skills and students as the final recipient of their teaching. The use of Blooms’s taxonomy enables teachers to classify the learning objectives into levels of complexity and specificity, thus making it possible to highlight the kind of knowledge teachers would like their students to reach. The fact that the instructional design features can be visualized through the IDEA platform is a guarantee for those who are looking for specific educational materials to be used in their lessons. Despite the benefits offered, a number of teachers are reluctant to use ISD because the preparatory work of having to thoroughly analyze the teaching/learning objectives, the planning of learning material, assessment activities, etc., is long and felt to be time-consuming. This drawback is minimized using a learning designer, as the tool facilitates to reuse of the didactic contents having a clear view of the processes of analysis, planning, and production of educational or testing materials uploaded on our platform. In this paper, we shall present the feedback of the teachers who used our tool in their didactic.Keywords: educational benefits, educational quality, educational technology, ISD tool
Procedia PDF Downloads 1922468 Woodfuels as Alternative Source of Energy in Rural and Urban Areas in the Philippines
Authors: R. T. Aggangan
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Woodfuels continue to be a major component of the energy supply mix of the Philippines due to increasing demand for energy that are not adequately met by decreasing supply and increasing prices of fuel oil such as liquefied petroleum gas (LPG) and kerosene. The Development Academy of the Philippines projects the demand of woodfuels in 2016 as 28.3 million metric tons in the household sector and about 105.4 million metric tons combined supply potentials of both forest and non-forest lands. However, the Revised Master Plan for Forestry Development projects a demand of about 50 million cu meters of fuelwood in 2016 but the capability to supply from local sources is only about 28 million cu meters indicating a 44 % deficiency. Household demand constitutes 82% while industries demand is 18%. Domestic household demand for energy is for cooking needs while the industrial demand is for steam power generation, curing barns of tobacco: brick, ceramics and pot making; bakery; lime production; and small scale food processing. Factors that favour increased use of wood-based energy include the relatively low prices (increasing oil-based fuel prices), availability of efficient wood-based energy utilization technology, increasing supply, and increasing population that cannot afford conventional fuels. Moreover, innovations in combustion technology and cogeneration of heat and power from biomass for modern applications favour biomass energy development. This paper recommends policies and strategic directions for the development of the woodfuel industry with the twin goals of sustainably supplying the energy requirements of households and industry.Keywords: biomass energy development, fuelwood, households and industry, innovations in combustion technology, supply and demand
Procedia PDF Downloads 3382467 Entrepreneurial Leadership in a Startup Context: A Comparative Study on Two Egyptian Startup Businesses
Authors: Nada Basset
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Problem Statement: The study examines the important role of leading change inside start-ups and highlights the challenges faced by an entrepreneur during the startup phase of the business. Research Methods/Procedures/Approaches: A qualitative research approach is taken, using the case study analysis method. A comparative study was made between two day care nurseries in Greater Cairo. Non-probability purposive sampling was used and a triangulation of semi-structured interviews, document analysis and participant-observation were applied simultaneously. The in-depth case study analysis took place over a longitudinal study of four calendar months. Results/Findings: Findings demonstrated that leading change in an entrepreneurial setup must be initiated by the entrepreneur, who must also be the owner of the change process. Another important finding showed that the culture of change, although created by the entrepreneur, needs the support and engagement of followers, who should be sharing the same value system and vision of the entrepreneur. Conclusions and Implications: An important implication suggests that during the first year of a start-up lifecycle, special emphasis must be made to the recruitment and selection of personnel, who should play a role into setting the new start-up culture and help it grow or shrink. Another drawn conclusion is that the success of the change must be measured in both quantitative and qualitative terms. Increasing revenues and customer attrition rates -as quantitative KPIs- must be aligned with other qualitative KPIs like customer satisfaction, employee satisfaction, and organizational commitment and business reputation. Originality of Paper: The paper addresses change management in an entrepreneurial concept, with an empirical application on an Egyptian start-up model providing a service to both adults and children. This privileges the research as the constructs measured merged together the level of satisfaction of employees, decision-makers (parents of children), and the users (children).Keywords: leadership, change management, entrepreneurship, startup business
Procedia PDF Downloads 1882466 Integrating Heritage Conservation and Sustainable Development: The Role of Buffer Zones in Safeguarding the Tentative World Heritage Sites and Empowering Local Communities in India
Authors: Shweta Vardia
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The 2021 decision by the World Heritage Center to align buffer zones with the 2015 Strategy for Sustainable Development marks a significant advancement in the protection of cultural and natural heritage sites. Buffer zones play a critical role in preserving the outstanding universal value, authenticity, and integrity of heritage sites, shielding them from threats such as urbanization, industrialization, and tourism. The 2015 Strategy emphasizes the integration of culture and heritage into sustainable development policies, highlighting the importance of community participation, traditional knowledge, and effective management in the conservation of heritage sites. This paper examines the implications of this strategic alignment for tentative World Heritage Sites in India. It explores how buffer zones can serve as tools for sustainable tourism, economic growth, and environmental protection while also addressing the socio-economic needs of local communities. By adopting a people-centered approach, the study underscores the need for active community involvement in heritage conservation, recognizing local residents as long-term custodians of cultural heritage. The role of buffer zones in promoting sustainable livelihoods, enhancing resilience to environmental changes, and fostering a sense of belonging among communities is also discussed. The challenges associated with buffer zones, including restrictive boundaries, unclear legislative frameworks, and potential disconnection from sociocultural contexts, are critically analyzed. The paper advocates for a holistic and integrated approach to buffer zone management, ensuring that policies are not only theoretically sound but also practically feasible. It concludes by emphasizing the need for collaborative efforts among conservation professionals, local communities, and policymakers to achieve sustainable development goals that respect both the heritage site's integrity and the well-being of surrounding populations.Keywords: buffer zones, India, local communities, urbanization, world heritage sites
Procedia PDF Downloads 372465 Effect of Antimony on Microorganisms in Aerobic and Anaerobic Environments
Authors: Barrera C. Monserrat, Sierra-Alvarez Reyes, Pat-Espadas Aurora, Moreno Andrade Ivan
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Antimony is a toxic and carcinogenic metalloid considered a pollutant of priority interest by the United States Environmental Protection Agency. It is present in the environment in two oxidation states: antimonite (Sb (III)) and antimony (Sb (V)). Sb (III) is toxic to several aquatic organisms, but the potential inhibitory effect of Sb species for microorganisms has not been extensively evaluated. The fate and possible toxic impact of antimony on aerobic and anaerobic wastewater treatment systems are unknown. For this reason, the objective of this study was to evaluate the microbial toxicity of Sb (V) and Sb (III) in aerobic and anaerobic environments. Sb(V) and Sb(III) were used as potassium hexahydroxoantimonate (V) and potassium antimony tartrate, respectively (Sigma-Aldrich). The toxic effect of both Sb species in anaerobic environments was evaluated on methanogenic activity and the inhibition of hydrogen production of microorganisms from a wastewater treatment bioreactor. For the methanogenic activity, batch experiments were carried out in 160 mL serological bottles; each bottle contained basal mineral medium (100 mL), inoculum (1.5 g of VSS/L), acetate (2.56 g/L) as substrate, and variable concentrations of Sb (V) or Sb (III). Duplicate bioassays were incubated at 30 ± 2°C on an orbital shaker (105 rpm) in the dark. Methane production was monitored by gas chromatography. The hydrogen production inhibition tests were carried out in glass bottles with a working volume of 0.36 L. Glucose (50 g/L) was used as a substrate, pretreated inoculum (5 g VSS/L), mineral medium and varying concentrations of the two species of antimony. The bottles were kept under stirring and at a temperature of 35°C in an AMPTSII device that recorded hydrogen production. The toxicity of Sb on aerobic microorganisms (from a wastewater activated sludge treatment plant) was tested with a Microtox standardized toxicity test and respirometry. Results showed that Sb (III) is more toxic than Sb (V) for methanogenic microorganisms. Sb (V) caused a 50% decrease in methanogenic activity at 250 mg/L. In contrast, exposure to Sb (III) resulted in a 50% inhibition at a concentration of only 11 mg/L, and an almost complete inhibition (95%) at 25 mg/L. For hydrogen-producing microorganisms, Sb (III) and Sb (V) inhibited 50% of this production with 12.6 mg/L and 87.7 mg/L, respectively. The results for aerobic environments showed that 500 mg/L of Sb (V) do not inhibit the Allivibrio fischeri (Microtox) activity or specific oxygen uptake rate of activated sludge. In the case of Sb (III), this caused a loss of 50% of the respiration of the microorganisms at concentrations below 40 mg/L. The results obtained indicate that the toxicity of the antimony will depend on the speciation of this metalloid and that Sb (III) has a significantly higher inhibitory potential compared to Sb (V). It was shown that anaerobic microorganisms can reduce Sb (V) to Sb (III). Acknowledgments: This work was funded in part by grants from the UA-CONACYT Binational Consortium for the Regional Scientific Development and Innovation (CAZMEX), the National Institute of Health (NIH ES- 04940), and PAPIIT-DGAPA-UNAM (IN105220).Keywords: aerobic inhibition, antimony reduction, hydrogen inhibition, methanogenic toxicity
Procedia PDF Downloads 1762464 Enhancing Inservice Education Training Effectiveness Using a Mobile Based E-Learning Model
Authors: Richard Patrick Kabuye
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This study focuses on the addressing the enhancement of in-service training programs as a tool of transforming the existing traditional approaches of formal lectures/contact hours. This will be supported with a more versatile, robust, and remotely accessible means of mobile based e-learning, as a support tool for the traditional means. A combination of various factors in education and incorporation of the eLearning strategy proves to be a key factor in effective in-service education. Key factor needs to be factored in so as to maintain a credible co-existence of the programs, with the prevailing social, economic and political environments. Effective in-service education focuses on having immediate transformation of knowledge into practice for a good time period, active participation of attendees, enable before training planning, in training assessment and post training feedback training analysis which will yield knowledge to the trainers of the applicability of knowledge given out. All the above require a more robust approach to attain success in implementation. Incorporating mobile technology in eLearning will enable the above to be factored together in a more coherent manner, as it is evident that participants have to take time off their duties and attend to these training programs. Making it mobile, will save a lot of time since participants would be in position to follow certain modules while away from lecture rooms, get continuous program updates after completing the program, send feedback to instructors on knowledge gaps, and a wholly conclusive evaluation of the entire program on a learn as you work platform. This study will follow both qualitative and quantitative approaches in data collection, and this will be compounded incorporating a mobile eLearning application using Android.Keywords: in service, training, mobile, e- learning, model
Procedia PDF Downloads 2232463 Modification of Hexagonal Boron Nitride Induced by Focused Laser Beam
Authors: I. Wlasny, Z. Klusek, A. Wysmolek
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Hexagonal boron nitride is a representative of a widely popular class of two-dimensional Van Der Waals materials. It finds its uses, among others, in construction of complexly layered heterostructures. Hexagonal boron nitride attracts great interest because of its properties characteristic for wide-gap semiconductors as well as an ultra-flat surface.Van Der Waals heterostructures composed of two-dimensional layered materials, such as transition metal dichalcogenides or graphene give hope for miniaturization of various electronic and optoelectronic elements. In our presentation, we will show the results of our investigations of the not previously reported modification of the hexagonal boron nitride layers with focused laser beam. The electrostatic force microscopy (EFM) images reveal that the irradiation leads to changes of the local electric fields for a wide range of laser wavelengths (from 442 to 785 nm). These changes are also accompanied by alterations of crystallographic structure of the material, as reflected by Raman spectra. They exhibit high stability and remain visible after at least five months. This behavior can be explained in terms of photoionization of the defect centers in h-BN which influence non-uniform electrostatic field screening by the photo-excited charge carriers. Analyzed changes influence local defect structure, and thus the interatomic distances within the lattice. These effects can be amplified by the piezoelectric character of hexagonal boron nitride, similar to that found in nitrides (e.g., GaN, AlN). Our results shed new light on the optical properties of the hexagonal boron nitride, in particular, those associated with electron-phonon coupling. Our study also opens new possibilities for h-BN applications in layered heterostructures where electrostatic fields can be used in tailoring of the local properties of the structures for use in micro- and nanoelectronics or field-controlled memory storage. This work is supported by National Science Centre project granted on the basis of the decision number DEC-2015/16/S/ST3/00451.Keywords: atomic force microscopy, hexagonal boron nitride, optical properties, raman spectroscopy
Procedia PDF Downloads 1772462 Trade Liberalization and Domestic Private Investment in Nigeria
Authors: George-Anokwuru Chioma Chidinma Bernadette
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This paper investigated the effect of trade liberalization on domestic private investment in Nigeria from 1981 to 2020. To achieve this objective, secondary data on domestic private investment, trade openness, exchange rate and interest rate were sourced from the statistical bulletin of Nigeria’s apex bank. The Autoregressive Distributed Lag (ARDL) technique was used as the main analytical tool. The ARDL Bounds test revealed the existence of long run association among the variables. The results revealed that trade openness and exchange rate have positive and insignificant relationship with domestic private investment both in the long and short runs. At the same time, interest rate has negative relationship with domestic private investment both in the long and short runs. Therefore, it was concluded that there is no significant relationship between trade openness, exchange rate, interest rate and domestic private investment in Nigeria during the period of study. Based on the findings, the study recommended that government should formulate trade policies that will encourage the growth of domestic private investment in Nigeria. To achieve this, government should ensure consistency in trade policies and at the same time strengthen the existing policies to build investors’ confidence. Also, government should make available an investment-friendly environment, as well as monitor real sector operators to ensure that foreign exchange allocations are not diverted. Government should increase capital investment in education, housing, transportation, agriculture, health, power, road construction, national defense, among others that will help the various sectors of the economy to function very well thereby making the business environment friendly thereby enhancing the growth and development of the country.Keywords: trade openness, domestic private investment, ARDL, exchange rate
Procedia PDF Downloads 74