Search results for: panel data analysis
15724 Impact of Herbicides on Soil Biology in Rapeseed
Authors: M. Eickermann, M. K. Class, J. Junk
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Winter oilseed rape, Brassica napus L., is characterized by a high number of herbicide applications. Therefore, its cultivation can lead to massive contamination of ground water and soil by herbicide and their metabolites. A multi-side long-term field experiment (EFFO, Efficient crop rotation) was set-up in Luxembourg to quantify these effects. Based on soil sampling and laboratory analysis, preliminary results showed reduced dehydrogenase activities of several soil organisms due to herbicide treatments. This effect is highly depending on the soil type. Relation between the dehydrogenase activity and the amount of microbial carbon showed higher variability on the test side with loamy Brown Earth, based on Bunter than on those with sandy-loamy Brown Earth, based on calciferous Sandstone.Keywords: cropping system, dehydrogenase activity, herbicides, mechanical weed control, oilseed rape
Procedia PDF Downloads 24715723 Application of Statistical Linearized Models for Investigations of Digital Dynamic Pulse-Frequency Control Systems
Authors: B. H. Aitchanov, Sh. K. Aitchanova, O. A. Baimuratov
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This paper is focused on dynamic pulse-frequency modulation (DPFM) control systems. Currently, the control law based on DPFM control signals is widely used in direct digital control subsystems introduced in the automated control systems of technological processes. Statistical analysis of automatic control systems is reduced to its construction of functional relationships between the statistical characteristics of the errors processes and input processes. Structural and dynamic Volterra models of digital pulse-frequency control systems can be used to develop methods for generating the dependencies, differing accuracy, requiring the amount of information about the statistical characteristics of input processes and computing labor intensity of their use.Keywords: digital dynamic pulse-frequency control systems, dynamic pulse-frequency modulation, control object, discrete filter, impulse device, microcontroller
Procedia PDF Downloads 49515722 Wireless Sensor Networks Optimization by Using 2-Stage Algorithm Based on Imperialist Competitive Algorithm
Authors: Hamid R. Lashgarian Azad, Seyed N. Shetab Boushehri
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Wireless sensor networks (WSN) have become progressively popular due to their wide range of applications. Wireless Sensor Network is made of numerous tiny sensor nodes that are battery-powered. It is a very significant problem to maximize the lifetime of wireless sensor networks. In this paper, we propose a two-stage protocol based on an imperialist competitive algorithm (2S-ICA) to solve a sensor network optimization problem. The energy of the sensors can be greatly reduced and the lifetime of the network reduced by long communication distances between the sensors and the sink. We can minimize the overall communication distance considerably, thereby extending the lifetime of the network lifetime through connecting sensors into a series of independent clusters using 2SICA. Comparison results of the proposed protocol and LEACH protocol, which is common to solving WSN problems, show that our protocol has a better performance in terms of improving network life and increasing the number of transmitted data.Keywords: wireless sensor network, imperialist competitive algorithm, LEACH protocol, k-means clustering
Procedia PDF Downloads 10315721 Relationship Demise After Having Children: An Analysis of Abandonment and Nuclear Family Structure vs. Supportive Community Cultures
Authors: John W. Travis
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There is an epidemic of couples separating after a child is born into a family, generally with the father leaving emotionally or physically in the first few years after birth. This separation creates high levels of stress for both parents, especially the primary parent, leaving her (or him) less available to the infant for healthy attachment and nurturing. The deterioration of the couple’s bond leaves parents increasingly under-resourced, and the dependent child in a compromised environment, with an increased likelihood of developing an attachment disorder. Objectives: To understand the dynamics of a couple, once the additional and extensive demands of a newborn are added to a nuclear family structure, and to identify effective ways to support all members of the family to thrive. Qualitative studies interviewed men, women, and couples after pregnancy and the early years as a family, regarding key destructive factors, as well as effective tools for the couple to retain a strong bond. In-depth analysis of a few cases, including the author’s own experience, reveal deeper insights about subtle factors, replicated in wider studies. Using a self-assessment survey, many fathers report feeling abandoned, due to the close bond of the mother-baby unit, and in turn, withdrawing themselves, leaving the mother without support and closeness to resource her for the baby. Fathers report various types of abandonment, from his partner to his mother, with whom he did not experience adequate connection as a child. The study identified a key destructive factor to be unrecognized wounding from childhood that was carried into the relationship. The study culminated in the naming of Male Postpartum Abandonment Syndrome (MPAS), describing the epidemic in industrialized cultures with the nuclear family as the primary configuration. A growing family system often collapses without a minimum number of adult caregivers per infant, approximately four per infant (3.87), which allows for proper healing and caretaking. In cases with no additional family or community beyond one or two parents, the layers of abandonment and trauma result in the deterioration of a couple’s relationship and ultimately the family structure. The solution includes engaging community in support of new families. The study identified (and recommends) specific resources to assist couples in recognizing and healing trauma and disconnection at multiple levels. Recommendations include wider awareness and availability of resources for healing childhood wounds and greater community-building efforts to support couples for the whole family to thrive.Keywords: abandonment, attachment, community building, family and marital functioning, healing childhood wounds, infant wellness, intimacy, marital satisfaction, relationship quality, relationship satisfaction
Procedia PDF Downloads 22515720 Optical Switching Based On Bragg Solitons in A Nonuniform Fiber Bragg Grating
Authors: Abdulatif Abdusalam, Mohamed Shaban
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In this paper, we consider the nonlinear pulse propagation through a nonuniform birefringent fiber Bragg grating (FBG) whose index modulation depth varies along the propagation direction. Here, the pulse propagation is governed by the nonlinear birefringent coupled mode (NLBCM) equations. To form the Bragg soliton outside the photonic bandgap (PBG), the NLBCM equations are reduced to the well known NLS type equation by multiple scale analysis. As we consider the pulse propagation in a nonuniform FBG, the pulse propagation outside the PBG is governed by inhomogeneous NLS (INLS) rather than NLS. We, then, discuss the formation of soliton in the FBG known as Bragg soliton whose central frequency lies outside but close to the PBG of the grating structure. Further, we discuss Bragg soliton compression due to a delicate balance between the SPM and the varying grating induced dispersion. In addition, Bragg soliton collision, Bragg soliton switching and possible logic gates have also been discussed.Keywords: Bragg grating, non uniform fiber, non linear pulse
Procedia PDF Downloads 31715719 Chemical Stability and Characterization of Ion Exchange Membranes for Vanadium Redox Flow Batteries
Authors: Min-Hwa Lim, Mi-Jeong Park, Ho-Young Jung
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Imidazolium-brominated polyphenylene oxide (Im-bPPO) is based on the functionalization of bromomethylated poly(2,6-dimethyl-1,4-phenylene oxide) (BPPO) using 1-Methylimdazole. For the purpose of long cycle life of vanadium redox battery (VRB), the chemical stability of Im-bPPO, sPPO (sulfonated 2,6-dimethyl-1,4-phenylene oxide) and Fumatech membranes were evaluated firstly in the 0.1M vanadium (V) solution dissolved in 3M sulfuric acid (H2SO4) for 72h, and UV analyses of the degradation products proved that ether bond in PPO backbone was vulnerable to be attacked by vanadium (V) ion. It was found that the membranes had slightly weight loss after soaking in 2 ml distilled water included in STS pressure vessel for 1 day at 200◦C. ATR-FT-IR data indicated before and after the degradation of the membranes. Further evaluation on the degradation mechanism of the menbranes were carried out in Fenton’s reagent solution for 72 h at 50 ◦C and analyses of the membranes before and after degradation confirmed the weight loss of the membranes. The Fumatech membranes exhibited better performance than AEM and CEM, but Nafion 212 still suffers chemical degradation.Keywords: vanadium redox flow battery, ion exchange membrane, permeability, degradation, chemical stability
Procedia PDF Downloads 30015718 Graphene-Based Nanobiosensors and Lab on Chip for Sensitive Pesticide Detection
Authors: Martin Pumera
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Graphene materials are being widely used in electrochemistry due to their versatility and excellent properties as platforms for biosensing. Here we present current trends in the electrochemical biosensing of pesticides and other toxic compounds. We explore two fundamentally different designs, (i) using graphene and other 2-D nanomaterials as an electrochemical platform and (ii) using these nanomaterials in the laboratory on chip design, together with paramagnetic beads. More specifically: (i) We explore graphene as transducer platform with very good conductivity, large surface area, and fast heterogeneous electron transfer for the biosensing. We will present the comparison of these materials and of the immobilization techniques. (ii) We present use of the graphene in the laboratory on chip systems. Laboratory on the chip had a huge advantage due to small footprint, fast analysis times and sample handling. We will show the application of these systems for pesticide detection and detection of other toxic compounds.Keywords: graphene, 2D nanomaterials, biosensing, chip design
Procedia PDF Downloads 55015717 Mechanical Properties of Ancient Timber Structure Based on the Non Destructive Test Method: A Study to Feiyun Building, Shanxi, China
Authors: Annisa Dewanti Putri, Wang Juan, Y. Qing Shan
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The structural assessment is one of a crucial part for ancient timber structure, in which this phase will be the reference for the maintenance and preservation phase. The mechanical properties of a structure are one of an important component of the structural assessment of building. Feiyun as one of the particular preserved building in China will become one of the Pioneer of Timber Structure Building Assessment. The 3-storey building which is located in Shanxi Province consists of complex ancient timber structure. Due to condition and preservation purpose, assessments (visual inspections, Non-Destructive Test and a Semi Non-Destructive test) were conducted. The stress wave measurement, moisture content analyzer, and the micro-drilling resistance meter data will overview the prediction of Mechanical Properties. As a result, the mechanical properties can be used for the next phase as reference for structural damage solutions.Keywords: ancient structure, mechanical properties, non destructive test, stress wave, structural assessment, timber structure
Procedia PDF Downloads 47415716 Comparison of Tensile Strength and Folding Endurance of (FDM Process) 3D Printed ABS and PLA Materials
Authors: R. Devicharan
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In a short span 3D Printing is expected to play a vital role in our life. The possibility of creativity and speed in manufacturing through various 3D printing processes is infinite. This study is performed on the FDM (Fused Deposition Modelling) method of 3D printing, which is one of the pre-dominant methods of 3D printing technologies. This study focuses on physical properties of the objects produced by 3D printing which determine the applications of the 3D printed objects. This paper specifically aims at the study of the tensile strength and the folding endurance of the 3D printed objects through the FDM (Fused Deposition Modelling) method using the ABS (Acronitirile Butadiene Styrene) and PLA (Poly Lactic Acid) plastic materials. The study is performed on a controlled environment and the specific machine settings. Appropriate tables, graphs are plotted and research analysis techniques will be utilized to analyse, verify and validate the experiment results.Keywords: FDM process, 3D printing, ABS for 3D printing, PLA for 3D printing, rapid prototyping
Procedia PDF Downloads 59915715 Comparison of Different Methods of Evaluating Nozzle Junction Stresses under External Loads
Authors: Vinod Kumar, Arun Kumar, Surjit Angra
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This paper addresses the junction stress analysis of orthogonally intersecting thin walled cylindrical shell and thin walled cylindrical nozzle subjected to external loading on nozzle. Junction stresses have been calculated theoretically by welding research council (WRC) bulletins 107 and 297 for different nozzle loads. WRC bulletins 107 and 297 have been used by design engineers for calculating nozzle-vessel junction stresses since their publication. They give simple empirical relations and easy in application. Also 3D FEA in which material is elastic has been done in ANSYS software with 8 node solid element model and results of FEA have been compared with WRC results. Stress intensities obtained by WRC 297 are generally slightly higher than obtained by WRC 107. Membrane stresses obtained by FEA are much higher than WRC and membrane plus bending stresses obtained by FEA are lower than WRC.Keywords: FEA, junction stress, solid element, WRC 107, WRC 297
Procedia PDF Downloads 58015714 The Molecular Mechanism of Vacuolar Function in Yeast Cell Homeostasis
Authors: Chang-Hui Shen, Paulina Konarzewska
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Cell homeostasis is regulated by vacuolar activity and it has been shown that lipid composition of the vacuole plays an important role in vacuolar function. The major phosphoinositide species present in the vacuolar membrane include phosphatidylinositol 3,5-biphosphate (PI(3,5)P₂) which is generated from PI(3)P controlled by Fab1p. Deletion of FAB1 gene reduce the synthesis of PI(3,5)P₂ and thus result in enlarged or fragmented vacuoles, with neutral vacuolar pH due to reduced vacuolar H⁺-ATPase activity. These mutants also exhibited poor growth at high extracellular pH and in the presence of CaCl₂. Conversely, VPS34 regulates the synthesis of PI(3)P from phosphatidylinositol (PI), and the lack of Vps34p results in the reduction of vacuolar activity. Although the cellular observations are clear, it is still unknown about the molecular mechanism between the phospholipid biosynthesis pathway and vacuolar activity. Since both VPS34 and FAB1 are important in vacuolar activity, we hypothesize that the molecular mechanism of vacuolar function might be regulated by the transcriptional regulators of phospholipid biosynthesis. In this study, we study the role of the major phospholipid biosynthesis transcription factor, INO2, in the regulation of vacuolar activity. We first performed qRT-PCR to examine the effect of Ino2p on the expression of VPS34 and FAB1. Our results showed that VPS34 was upregulated in the presence of inositol for both WT and ino2Δ cells. However, FAB1 was only upregulated significantly in ino2Δ cells. This indicated that Ino2p might be the negative regulator for FAB1 expression. Next, growth sensitivity experiment showed that WT, vma3Δ, and ino2Δ grew well in growth medium buffered to pH 5.5 containing 10 mM CaCl₂. As cells were switched to growth medium buffered to pH 7 containing CaCl₂ WT, ino2Δ and opi1Δ showed growth reduction, whereas vma3Δ was completely nonviable. As the concentration of CaCl₂ was increased to 60 mM, ino2Δ cells showed moderate growth reduction compared to WT. This result suggests that ino2Δ cells have better vacuolar activity. Microscopic analysis and vacuolar acidification were employed to further elucidate the importance of INO2 in vacuolar homeostasis. Analysis of vacuolar morphology indicated that WT and vma3Δ cells displayed vacuoles that occupied a small area of the cell when grown in media buffered to pH 5.5. Whereas, ino2Δ displayed fragmented vacuoles. On the other hand, all strains grown in media buffered to pH 7, exhibited enlarged vacuoles that occupied most of the cell’s surface. This indicated that the presence of INO2 may play negative effect in vacuolar morphology when cells are grown in media buffered to pH 5.5. Furthermore, vacuolar acidification assay showed that only vma3Δ cells displayed notably less acidic vacuoles as cells were grown in media buffered to pH 5.5 and pH 7. Whereas, ino2Δ cells displayed more acidic pH compared to WT at pH7. Taken together, our results demonstrated the molecular mechanism of the vacuolar activity regulated by the phospholipid biosynthesis transcription factors Ino2p. Ino2p negatively regulates vacuolar activity through the expression of FAB1.Keywords: vacuole, phospholipid, homeostasis, Ino2p, FAB1
Procedia PDF Downloads 12715713 Study of Icons in Enterprise Application Software Context
Authors: Shiva Subhedar, Abhishek Jain, Shivin Mittal
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Icons are not merely decorative elements in enterprise applications but very often used because of their many advantages such as compactness, visual appeal, etc. Despite these potential advantages, icons often cause usability problems when they are designed without consideration for their many potential downsides. The aim of the current study was to examine the effect of articulatory distance – the distance between the physical appearance of an interface element and what it actually means. In other words, will the subject find the association of the function and its appearance on the interface natural or is the icon difficult for them to associate with its function. We have calculated response time and quality of identification by varying icon concreteness, the context of usage and subject experience in the enterprise context. The subjects were asked to associate icons (prepared for study purpose) with given function options in context and out of context mode. Response time and their selection were recorded for analysis.Keywords: HCI, icons, icon concreteness, icon recognition
Procedia PDF Downloads 25815712 Hydrothermal Synthesis of Mesoporous Carbon Nanospheres and Their Electrochemical Properties for Glucose Detection
Authors: Ali Akbar Kazemi Asl, Mansour Rahsepar
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Mesoporous carbon nanospheres (MCNs) with uniform particle size distribution having an average of 290 nm and large specific surface area (274.4 m²/g) were synthesized by a one-step hydrothermal method followed by the calcination process and then utilized as an enzyme-free glucose biosensor. Morphology, crystal structure, and porous nature of the synthesized nanospheres were characterized by scanning electron microscopy (SEM), X-Ray diffraction (XRD), and Brunauer–Emmett–Teller (BET) analysis, respectively. Also, the electrochemical performance of the MCNs@GCE electrode for the measurement of glucose concentration in alkaline media was investigated by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and chronoamperometry (CA). MCNs@GCE electrode shows good sensing performance, including a rapid glucose oxidation response within 3.1 s, a wide linear range of 0.026-12 mM, a sensitivity of 212.34 μA.mM⁻¹.cm⁻², and a detection limit of 25.7 μM with excellent selectivity.Keywords: biosensor, electrochemical, glucose, mesoporous carbon, non-enzymatic
Procedia PDF Downloads 19015711 The Effect of Physical Biorhythm Cycle on Health-Related Fitness Factors
Authors: Leyli Khavari, Javad Yousefian
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The aim of this study was to investigate the effect of physical biorhythm cycle on health-related fitness factors. For this purpose, 120 athlete and non-athlete male and female students were selected randomly and based on the level of physical activity divided into athletic and non-athletic groups. The exact date of birth and also when the subjects were in the positive, negative and critical physical biorhythm cycle was determined by calculation software biorhythm. The physical fitness factors tests, including Queens College Step Test, AAHPERD sit-ups; Wells stretch test and hand dynamometer. Students in three stages in positive, negative and critical physical cycle were tested. Data processing using SPSS software and statistical tests ANOVA with repeated measures and student t test was used for dependent. The results of this study showed that changes in physical fitness and physical biorhythm were not affected by changes in the 23-day physical cycle.Keywords: AAHPERD test, biorhythm, physical cycle, Queens College Step Test
Procedia PDF Downloads 18215710 Reuse of Historic Buildings for Tourism: Policy Gaps
Authors: Joseph Falzon, Margaret Nelson
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Background: Regeneration and re-use of abandoned historic buildings present a continuous challenge for policy makers and stakeholders in the tourism and leisure industry. Obsolete historic buildings provide great potential for tourism and leisure accommodation, presenting unique heritage experiences to travellers and host communities. Contemporary demands in the hospitality industry continuously require higher standards, some of which are in conflict with heritage conservation principles. Objective: The aim of this research paper is to critically discuss regeneration policies with stakeholders of the tourism and leisure industry and to examine current practices in policy development and the resultant impact of policies on the Maltese tourism and leisure industry. Research Design: Six semi-structured interviews with stakeholders involved in the tourism and leisure industry participated in the research. A number of measures were taken to reduce bias and thus improve trustworthiness. Clear statements of the purpose of the research study were provided at the start of each interview to reduce expectancy bias. The interviews were semi-structured to minimise interviewer bias. Interviewees were allowed to expand and elaborate as necessary, with only necessary probing questions, to allow free expression of opinion and practices. Interview guide was submitted to participants at least two weeks before the interview to allow participants to prepare for the interview and prevent recall bias during the interview as much as possible. Interview questions and probes contained both positive and negative aspects to prevent interviewer bias. Policy documents were available during the interview to prevent recall bias. Interview recordings were transcribed ‘intelligent’ verbatim. Analysis was carried out using thematic analysis with the coding frame developed independently by two researchers. All phases of the study were governed by research ethics. Findings: Findings were grouped in main themes: financing of regeneration, governance, legislation and policies. Other key issues included value of historic buildings and approaches for regeneration. Whist regeneration of historic buildings was noted, participants discussed a number of barriers that hindered regeneration. Stakeholders identified gaps in policies and gaps at policy implementation stages. European Union funding policies facilitated regeneration initiatives but funding criteria based on economic deliverables presented the intangible heritage gap. Stakeholders identified niche markets for heritage tourism accommodation. Lack of research-based policies was also identified. Conclusion: Potential of regeneration is hindered by inadequate legal framework that supports contemporary needs of the tourism industry. Policies should be developed by active stakeholder participation. Adequate funding schemes have to support the tangible and intangible components of the built heritage.Keywords: governance, historic buildings, policy, tourism
Procedia PDF Downloads 23615709 Physical Properties of Nine Nigerian Staple Food Flours Related to Bulk Handling and Processing
Authors: Ogunsina Babatunde, Aregbesola Omotayo, Adebayo Adewale, Odunlami Johnson
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The physical properties of nine Nigerian staple food flours related to bulk handling and processing were investigated following standard procedures. The results showed that the moisture content, bulk density, angle of repose, water absorption capacity, swelling index, dispersability, pH and wettability of the flours ranged from 9.95 to 11.98%, 0.44 to 0.66 g/cm3, 31.43 to 39.65o, 198.3 to 291.7 g of water/100 g of sample, 5.53 to 7.63, 60.3 to 73.8%, 4.43 to 6.70, and 11 to 150 s. The particle size analysis of the flour samples indicated significant differences (p<0.05). The least gelation concentration of the flour samples ranged from 6 to 14%. The colour of the flours fell between light and saturated, with the exception of cassava, millet and maize flours which appear dark and dull. The properties of food flours depend largely on the inherent property of the food material and may influence their functional behaviour as food materials.Keywords: properties, flours, staple food, bulk handling
Procedia PDF Downloads 48115708 Encapsulation of Volatile Citronella Essential oil by Coacervation: Efficiency and Release Kinetic Study
Authors: Rafeqah Raslan, Mastura AbdManaf, Junaidah Jai, Istikamah Subuki, Ana Najwa Mustapa
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The volatile citronella essential oil was encapsulated by simple coacervation and complex coacervation using gum Arabic and gelatin as wall material. Glutaraldehyde was used in the methodology as crosslinking agent. The citronella standard calibration graph was developed with R2 equal to 0.9523 for the accurate determination of encapsulation efficiency and release study. The release kinetic was analyzed based on Fick’s law of diffusion for polymeric system and linear graph of log fraction release over log time was constructed to determine the release rate constant, k and diffusion coefficient, n. Both coacervation methods in the present study produce encapsulation efficiency around 94%. The capsules morphology analysis supported the release kinetic mechanisms of produced capsules for both coacervation process.Keywords: simple coacervation, complex coacervation, encapsulation efficiency, release kinetic study
Procedia PDF Downloads 31615707 Enterpreneurship as a Strategic Tool for Higher Productivity in Nigerian Universities System
Authors: Yahaya Salihu Emeje, Amuchie Austine Anthony
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The topic examined the prospects of entrepreneurship as an emerging dynamic and strategic tool in the upliftment of human and non-human resources in the Nigerian university system, with a view of showcasing the abundant positive impact, on the Nigerian University system in particular and Nigerian economy at large. It is end at bringing out the benefits of entrepreneurship in the university system which includes, namely cultivating the culture of enterprise in University system; improvement in the quality and quantity of both human and non-human resources; innovative and creative methods of production; new employment strategies in the University system; improved sources of internal generated revenue; entrepreneurship as the culture of sustainability within and outside the university system. Secondary data was used in analyzing entrepreneurship as a productivity tool in the Nigeria University system. From the findings, the university system could be enriched through innovative ideas and technical revenue and employment generation; sustainable financial and economic base; university autonomy and improved international ranking of Nigerian Universities system; therefore, recommended that entrepreneurship is necessary therapy for reviving the ailing, Nigerian universities system.Keywords: entrepreneurship, strategic, productivity, universities
Procedia PDF Downloads 39515706 Forensic Investigation Into the Variation of Geological Properties of Soils Bintulu, Sarawak
Authors: Jaithish John
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In this paper a brief overview is provided of the developments in interdisciplinary knowledge exchange with use of soil and geological (earth) materials in the search for evidence. The aim is to provide background information on the role and value of understanding ‘earth materials’ from the crime scene through to microscopic scale investigations to support law enforcement agencies in solving criminal and environmental concerns and investigations. This involves the sampling, analysis, interpretation and explanation presentation of all these evidences. In this context, field and laboratory methods are highlighted for the controlled / referenced sample, alibi sample and questioned sample. The aim of forensic analyses of earth materials is to associate these samples taken from a questioned source to determine if there are similar and outstanding characteristics features of earth materials crucial to support the investigation to the questioned earth materials and compare it to the controlled / referenced sample and alibi samples.Keywords: soil, texture, grain, microscopy
Procedia PDF Downloads 8415705 A Study of the Weld Properties of Inconel 625 Based on Nb Content
Authors: JongWon Han, NoHoon Kim, HyoIk Ahn, HaeWoo Lee
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In this study, shielded metal arc welding was performed as a function of Nb content at 2.24 wt%, 3.25 wt%, and 4.26 wt%. The microstructure was observed using scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS) and showed the development of a columnar dendrite structure in the specimen having the least Nb content. From the hardness test, the hardness value was confirmed to reduce with decreasing Nb content. From electron backscatter diffraction (EBSD) analysis, the largest grain size was found in the specimen with Nb content of 2.24 wt%. The potentiodynamic polarization test was carried out to determine the pitting corrosion resistance; there was no significant difference in the pitting corrosion resistance with increasing Nb content. To evaluate the degree of sensitization to intergranular corrosion, the Double Loop Electrochemical Potentiodynamic Reactivation(DL-EPR test) was conducted. A similar degree of sensitization was found in two specimens except with a Nb content of 2.24 wt%, while a relatively high degree of sensitization was found in the specimen with a Nb content of 2.24 wt%.Keywords: inconel 625, Nb content, potentiodynamic test, DL-EPR test
Procedia PDF Downloads 30815704 Effective Communication with the Czech Customers 50+ in the Financial Market
Authors: K. Matušínská, H. Starzyczná, M. Stoklasa
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The paper deals with finding and describing of the effective marketing communication forms relating to the segment 50+ in the financial market in the Czech Republic. The segment 50+ can be seen as a great marketing potential in the future but unfortunately the Czech financial institutions haven´t still reacted enough to this fact and they haven´t prepared appropriate marketing programs for this customers´ segment. Demographic aging is a fundamental characteristic of the current European population evolution but the perspective of further population aging is more noticeable in the Czech Republic. This paper is based on data from one part of primary marketing research. Paper determinates the basic problem areas as well as definition of marketing communication in the financial market, defining the primary research problem, hypothesis and primary research methodology. Finally suitable marketing communication approach to selected sub-segment at age of 50-60 years is proposed according to marketing research findings.Keywords: population aging in the Czech Republic, segment 50+, financial services, marketing communication, marketing research, marketing communication approach
Procedia PDF Downloads 43715703 Analysis of Some Produced Inhibitors for Corrosion of J55 Steel in NaCl Solution Saturated with CO₂
Authors: Ambrish Singh
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The corrosion inhibition performance of pyran (AP) and benzimidazole (BI) derivatives on J55 steel in 3.5% NaCl solution saturated with CO₂ was investigated by electrochemical, weight loss, surface characterization, and theoretical studies. The electrochemical studies included electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), electrochemical frequency modulation (EFM), and electrochemical frequency modulation trend (EFMT). Surface characterization was done using contact angle, scanning electron microscopy (SEM), and atomic force microscopy (AFM) techniques. DFT and molecular dynamics (MD) studies were done using Gaussian and Materials Studio softwares. All the studies suggested the good inhibition by the synthesized inhibitors on J55 steel in 3.5% NaCl solution saturated with CO₂ due to the formation of a protective film on the surface. Molecular dynamic simulation was applied to search for the most stable configuration and adsorption energies for the interaction of the inhibitors with Fe (110) surface.Keywords: corrosion, inhibitor, EFM, AFM, DFT, MD
Procedia PDF Downloads 10515702 Challenges of Cryogenic Fluid Metering by Coriolis Flowmeter
Authors: Evgeniia Shavrina, Yan Zeng, Boo Cheong Khoo, Vinh-Tan Nguyen
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The present paper is aimed at providing a review of error sources in cryogenic metering by Coriolis flowmeters (CFMs). Whereas these flowmeters allow accurate water metering, high uncertainty and low repeatability are commonly observed at cryogenic fluid metering, which is often necessary for effective renewable energy production and storage. The sources of these issues might be classified as general and cryogenic specific challenges. A conducted analysis of experimental and theoretical studies shows that material behaviour at cryogenic temperatures, composition variety, and multiphase presence are the most significant cryogenic challenges. At the same time, pipeline diameter limitation, ambient vibration impact, and drawbacks of the installation may be highlighted as the most important general challenges of cryogenic metering by CFM. Finally, the techniques, which mitigate the impact of these challenges are reviewed, and future development direction is indicated.Keywords: Coriolis flowmeter, cryogenic, multicomponent flow, multiphase flow
Procedia PDF Downloads 15315701 PM10 Prediction and Forecasting Using CART: A Case Study for Pleven, Bulgaria
Authors: Snezhana G. Gocheva-Ilieva, Maya P. Stoimenova
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Ambient air pollution with fine particulate matter (PM10) is a systematic permanent problem in many countries around the world. The accumulation of a large number of measurements of both the PM10 concentrations and the accompanying atmospheric factors allow for their statistical modeling to detect dependencies and forecast future pollution. This study applies the classification and regression trees (CART) method for building and analyzing PM10 models. In the empirical study, average daily air data for the city of Pleven, Bulgaria for a period of 5 years are used. Predictors in the models are seven meteorological variables, time variables, as well as lagged PM10 variables and some lagged meteorological variables, delayed by 1 or 2 days with respect to the initial time series, respectively. The degree of influence of the predictors in the models is determined. The selected best CART models are used to forecast future PM10 concentrations for two days ahead after the last date in the modeling procedure and show very accurate results.Keywords: cross-validation, decision tree, lagged variables, short-term forecasting
Procedia PDF Downloads 19415700 A Systematic Review of Ethical Leadership in Tourism and Hospitality Settings
Authors: Majd Megheirkouni
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The aim of this study is to identify empirical studies that explore and investigate ethical leadership in order to assess and synthesize its impacts and outcomes. This study seeks to provide an evidence-informed answer to a set of questions on ethical leadership definition in the field of tourism and hospitality, its investigation, and examination, and its outcome. A systematic literature review, using medical science-based methodology, was conducted to synthesize research by reliable means. Four themes were identified from the analysis. These themes are: Ethical leaders’ characteristics, healthy work environment, ethical leadership effectiveness, and the application of ethical leadership across cultures. This study provides the potential to move hospitality and tourism leadership forward and encourage researchers to investigate new research topics. To the best of the author’s knowledge, this is the first systematic review focusing on ethical leadership in tourism and hospitality settings.Keywords: ethical leadership, approach, outcome, tourism, hospitality, systematic review
Procedia PDF Downloads 10015699 Selenium Content in Agricultural Soils and Wheat from the Balkan Peninsula
Authors: S. Krustev, V. Angelova, P. Zaprjanova
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Selenium (Se) is an essential micro-nutrient for human and animals but it is highly toxic. Its organic compounds play an important role in biochemistry and nutrition of the cells. Concentration levels of this element in the different regions of the world vary considerably. This study aimed to compare the availability and levels of the Se in some rural areas of the Balkan Peninsula and relationship with the concentrations of other trace elements. For this purpose soil samples and wheat grains from different regions of Bulgaria, Serbia, Nord Macedonia, Romania, and Greece situated far from large industrial centers have been analyzed. The main methods for their determination were the atomic spectral techniques – atomic absorption and plasma atomic emission. As a result of this study, data on microelements levels from the main grain-producing regions of the Balkan Peninsula were determined and systematized. The presented results confirm the low levels of Se in this region: 0.222– 0.962 mg.kg-1 in soils and 0.001 - 0.005 mg.kg-1 in wheat grains and require measures to offset the effect of this deficiency.Keywords: agricultural soils, balkan peninsula, rural areas, selenium
Procedia PDF Downloads 13215698 A Community Solution to Address Extensive Nitrate Contamination in the Lower Yakima Valley Aquifer
Authors: Melanie Redding
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Historic widespread nitrate contamination of the Lower Yakima Valley aquifer in Washington State initiated a community-based effort to reduce nitrate concentrations to below-drinking water standards. This group commissioned studies on characterizing local nitrogen sources, deep soil assessments, drinking water, and assessing nitrate concentrations at the water table. Nitrate is the most prevalent groundwater contaminant with common sources from animal and human waste, fertilizers, plants and precipitation. It is challenging to address groundwater contamination when common sources, such as agriculture, on-site sewage systems, and animal production, are widespread. Remediation is not possible, so mitigation is essential. The Lower Yakima Valley is located over 175,000 acres, with a population of 56,000 residents. Approximately 25% of the population do not have access to safe, clean drinking water, and 20% of the population is at or below the poverty level. Agriculture is the primary economic land-use activity. Irrigated agriculture and livestock production make up the largest percentage of acreage and nitrogen load. Commodities include apples, grapes, hops, dairy, silage corn, triticale, alfalfa and cherries. These commodities are important to the economic viability of the residents of the Lower Yakima Valley, as well as Washington State. Mitigation of nitrate in groundwater is challenging. The goal is to ensure everyone has safe drinking water. There are no easy remedies due to the extensive and pervasiveness of the contamination. Monitoring at the water table indicates that 45% of the 30 spatially distributed monitoring wells exceeded the drinking water standard. This indicates that there are multiple sources that are impacting water quality. Washington State has several areas which have extensive groundwater nitrate contamination. The groundwater in these areas continues to degrade over time. However, the Lower Yakima Valley is being successful in addressing this health issue because of the following reasons: the community is engaged and committed; there is one common goal; there has been extensive public education and outreach to citizens; and generating credible data using sound scientific methods. Work in this area is continuing as an ambient groundwater monitoring network is established to assess the condition of the aquifer over time. Nitrate samples are being collected from 170 wells, spatially distributed across the aquifer. This research entails quarterly sampling for two years to characterize seasonal variability and then continue annually afterward. This assessment will provide the data to statistically determine trends in nitrate concentrations across the aquifer, over time. Thirty-three of these wells are monitoring wells that are screened across the aquifer. The water quality from these wells are indicative of activities at the land surface. Additional work is being conducted to identify land use management practices that are effective in limiting nitrate migration through the soil column. Tracking nitrate in the soil column every season is an important component of bridging land-use practices with the fate and transport of nitrate through the subsurface. Patience, tenacity, and the ability to think outside the box are essential for dealing with widespread nitrate contamination of groundwater.Keywords: community, groundwater, monitoring, nitrate
Procedia PDF Downloads 17715697 Polymer in Electronic Waste: An Analysis
Authors: Anis A. Ansari, Aftab A. Ansari
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Electronic waste is inundating the traditional solid-waste-disposal facilities, which are inadequately designed to handle and manage such type of new wastes. Since electronic waste contains mostly hazardous and even toxic materials, the seriousness of its effects on human health and the environment cannot be ignored in present scenario. Waste from the electronic industry is increasing exponentially day by day. From the last 20 years, we are continuously generating huge quantities of e-waste such as obsolete computers and other discarded electronic components, mainly due to evolution of newer technologies as a result of constant efforts in research and development in this sector. Polymers, one of the major constituents in almost every electronic waste, such as computers, printers, electronic equipment, entertainment devices, mobile phones, television sets etc., are if properly recycled can create a new business opportunity. This would not only create potential market for polymers to improve economy but also the priceless land used as dumping sites of electronic waste, can be utilized for other productive purposes.Keywords: polymer recycling, electronic waste, hazardous materials, electronic components
Procedia PDF Downloads 47515696 Evaluation of Esters Production by Oleic Acid Epoxidation Reaction
Authors: Flavio A. F. Da Ponte, Jackson Q. Malveira, Monica C. G. Albuquerque
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In recent years a worldwide interest in renewable resources from the biomass has spurred the industry. In this work the chemical structure of oleic acid chains was modified by homogeneous and heterogeneous catalysis in order to produce esters. The homogeneous epoxidation was carried out at H2O2 to oleic acid unsaturation molar ratio of 20:1. The reaction temperature was 338 K and reaction time 16 h. Formic acid was used as catalyst. For heterogeneous catalysis reaction temperature was 343 K and reaction time 24 h. The esters production was carried out by heterogeneous catalysis of the epoxidized oleic acid and butanol using Mg/SBA-15 as catalyst. The resulting products were confirmed by NMR (1H and 13C) and FTIR spectroscopy. The products were characterized before and after each reaction. The catalysts were characterized by X-ray diffraction, X-ray fluorescence, thermogravimetric analysis (TGA) and BET surface areas. The results were satisfactory for the bioproducts formed.Keywords: acid oleic, bioproduct, esters, epoxidation
Procedia PDF Downloads 35615695 Learning Algorithms for Fuzzy Inference Systems Composed of Double- and Single-Input Rule Modules
Authors: Hirofumi Miyajima, Kazuya Kishida, Noritaka Shigei, Hiromi Miyajima
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Most of self-tuning fuzzy systems, which are automatically constructed from learning data, are based on the steepest descent method (SDM). However, this approach often requires a large convergence time and gets stuck into a shallow local minimum. One of its solutions is to use fuzzy rule modules with a small number of inputs such as DIRMs (Double-Input Rule Modules) and SIRMs (Single-Input Rule Modules). In this paper, we consider a (generalized) DIRMs model composed of double and single-input rule modules. Further, in order to reduce the redundant modules for the (generalized) DIRMs model, pruning and generative learning algorithms for the model are suggested. In order to show the effectiveness of them, numerical simulations for function approximation, Box-Jenkins and obstacle avoidance problems are performed.Keywords: Box-Jenkins's problem, double-input rule module, fuzzy inference model, obstacle avoidance, single-input rule module
Procedia PDF Downloads 352