Search results for: variation detracting property

Authors: Feng-jie Xie, Jian-hong Yan

Abstract:

Based on the complex network theory, we construct the air cargo network of the Belt and Road area, analyze its regional distribution and structural characteristics, measure the robustness of the network. The regional distribution results show that Southeast Asia and China have the most prominent development in the air cargo network of the Belt and Road area, Central Asia is the least developed. The structure characteristics found that the air cargo network has obvious small-world characteristics; the degree distribution has single-scale property; it shows a significant rich-club phenomenon simultaneously. The network robustness is measured by two attack strategies of degree and betweenness, but the betweenness of network nodes has a greater impact on network connectivity. And identified 24 key cities that have a large impact on the robustness of the network under the two attack strategies. Based on these results, recommendations are given to maintain the air cargo network connectivity in the Belt and Road area.

Keywords: air cargo, complex network, robustness, structure properties, The Belt and Road

Procedia PDF Downloads 191

Authors: Saima Nazir, Mustansar Ali Ghazanfar, Sanay Muhammad Umar Saeed, Muhammad Awais Azam, Saad Ali Alahmari

Abstract:

Terrorism is an important and challenging concern. The entire world is threatened by only few sophisticated terrorist groups and especially in Gulf Region and Pakistan, it has become extremely destructive phenomena in recent years. Predicting the pattern of attack type, attack group and target type is an intricate task. This study offers new insight on terrorist group’s attack type and its chosen target. This research paper proposes a framework for prediction of terrorist attacks using the historical data and making an association between terrorist group, their attack type and target. Analysis shows that the number of attacks per year will keep on increasing, and Al-Harmayan in Saudi Arabia, Al-Qai’da in Gulf Region and Tehreek-e-Taliban in Pakistan will remain responsible for many future terrorist attacks. Top main targets of each group will be private citizen & property, police, government and military sector under constant circumstances.

Keywords: data mining, counter terrorism, machine learning, SVM

Procedia PDF Downloads 403

Authors: Seung-Lock Seo

Abstract:

This work presents a data-mining empirical monitoring scheme for industrial processes with partially unbalanced data. Measurement data of good operations are relatively easy to gather, but in unusual special events or faults it is generally difficult to collect process information or almost impossible to analyze some noisy data of industrial processes. At this time some noise filtering techniques can be used to enhance process monitoring performance in a real-time basis. In addition, pre-processing of raw process data is helpful to eliminate unwanted variation of industrial process data. In this work, the performance of various monitoring schemes was tested and demonstrated for discrete batch process data. It showed that the monitoring performance was improved significantly in terms of monitoring success rate of given process faults.

Keywords: data mining, process data, monitoring, safety, industrial processes

Procedia PDF Downloads 394

Authors: Moreno Liso Lourdes

Abstract:

The industrial design protects the appearance of part or all of a product resulting from the features of, in particular, the lines, contours, colors, shape, texture or materials of the product itself or its ornamentation. The industrial property offers a different answer depending on the characteristics of the shape object of protection possible, including the trademark and industrial design. There are certain cases where the trademark right invalidate the exclusive right of the industrial design. This can occur in the following situations: 1st) collected as a sign design and trademarked; and 2nd) you want to trademark and protected as a form design (either registered or unregistered). You can either get a trade mark or design right in the same sign or form, provided it meets the legal definition of brand and design and meets the requirements imposed for the protection of each of them, even able to produce an overlap of protection. However, this double protection does not have many advantages. It is, therefore, necessary to choose the best form of legal protection according to the most adequate ratios. The diversity of rights that can use the creator of an industrial design to protect your job requires you to make a proper selection to prevent others, especially their competitors, taking advantage of the exclusivity that guarantees the law. It is necessary to choose between defending the interests of the parties through a judicial or extrajudicial procedure when the conflict arises. In this paper, we opted for the defense through mediation.

Keywords: industrial design, ADR, Law, EUIPO

Procedia PDF Downloads 237

Authors: Arjun Dakuri, J. Hayavadana

Abstract:

The study includes selection of 100 % bamboo fabric and cotton fabric for the study. The 100% bamboo fabrics were of 127 g/m², and 112 g/m² and 100% cotton grey fabric were of 104 g/m². The cotton fabric was desized, scoured, bleached and then treated with ZnO (as antimicrobial agent) with 1%, 2% and 3% using pad-dry cure method, whereas the bamboo fabrics were only desized. The antimicrobial activity of bamboo and ZnO treated cotton fabrics were evaluated and compared against E. coli and S. aureus as per the standard AATCC - 147. Moisture management properties of selected fabrics were also analyzed. Further, the selected fabric samples were tested for comfort properties like bending length, tearing strength, drape-ability, and specific handle force and air permeability. It was observed that bamboo fabrics show significant antibacterial activity and the same was shown by 3% ZnO treated cotton fabric. Both cotton and bamboo fabrics show improved moisture management properties than the cotton fabric. The comfort properties of bamboo fabrics are found to be superior to cotton fabrics making it more suitable for applications in place of cotton.

Keywords: antimicrobial activity, bamboo, cotton, comfort properties, moisture management, zinc oxide

Procedia PDF Downloads 349

Authors: Richard E. Miller

Abstract:

12.7-mm thick plates of 6061-T6511 aluminum alloy and high hardness steel (528 HV) were successfully joined by a friction stir bonding process using a tungsten-rhenium stir tool. Process parameter variation experiments, which included tool design geometry, plunge and traverse rates, tool offset, spindle tilt, and rotation speed, were conducted to develop a parameter set which yielded a defect free joint. Laboratory tensile tests exhibited yield stresses which exceed the strengths of comparable AA6061-to-AA6061 fusion and friction stir weld joints. Scanning electron microscopy and energy dispersive X-ray spectroscopy analysis also show atomic diffusion at the material interface region.

Keywords: dissimilar materials, friction stir, welding, materials science

Procedia PDF Downloads 263

Authors: R. Ziaie Moayed, H. Keshavarz Hedayati

Abstract:

Over recent years, due to increased population and increased waste production, groundwater protection has become more important, therefore, designing engineered barrier systems such as landfill liners to prevent the entry of leachate into groundwater should be done with greater accuracy. These measures generally involve the application of low permeability soils such as clays. Bentonite is a natural clay with low permeability which makes it a suitable soil for using in liners. Also zeolite with high cation exchange capacity can help to reduce of hazardous materials risk. Bentonite expands when wet, absorbing as much as several times its dry mass in water. This property may effect on some structural properties of soil such as shear strength. In present study, shear strength parameters are determined by both leachates polluted and not polluted bentonite-amended zeolite soil with mixing rates (B/Z) of 5%-10% and 20% with unconfined compression test to obtain the differences. It is shown that leachate presence causes reduction in resistance in general.

Keywords: bentonite, leachate, shear strength parameters, unconfined compression test

Procedia PDF Downloads 101

Authors: Bright Msukwa

Abstract:

Background: Malawi suffered economic instability, bad weather and massive flooding in the year 2015. A massive flood in the country, mainly in the southern region lead to damage of agriculture products. As a result, one of the heavily affected was Zingwangwa, Blantyre. Methods: We interviewed a selected number of houses residing in donor constructed temporal shelters and those still residing close to the floods prone areas in Zingwangwa, Blantyre. Results: About 67% of the population insisted that they resided on the land, which was prone to the floods as it belonged to their ancestors and their staying was part of preserving ancestral values. The remaining 23% of the population demonstrated economic challenges due to floods that contributed to the damage of their food crops, property and houses. Conclusion: Beliefs can negatively affect economic life improvement if mindsets are not changed among people in the rural area. Recommendation: Improving natural resource management, climate and disaster resilience.

Keywords: economic, belief, walfare, poverty

Procedia PDF Downloads 197

Authors: Omran Alharbi

Abstract:

It is difficult to find an aspect of our modern lives that has been untouched by mobile technology. Indeed, the use of mobile learning in Saudi Arabia may enhance students’ learning and increase overall educational standards. However, within tertiary education, the success of e-learning implementation depends on the degree to which students and educators accept mobile learning and are willing to utilise it. Therefore, this research targeted the factors that influence Hail University instructors’ intentions to use mobile learning. An online survey was completed by eighty instructors and it was found that their use of mobile learning was heavily predicted by performance experience, effort expectancy, social influence, and facilitating conditions; the multiple regression analysis revealed that 67% of the variation was accounted for by these variables. From these variables, effort expectancy was shown to be the strongest predictor of intention to use e-learning for instructors.

Keywords: acceptance, faculty member, mobile learning, KSA

Procedia PDF Downloads 149

Authors: Vadim E. Levit, Eugen Mandrescu

Abstract:

A graph is well-covered if all its maximal independent sets are of the same size. A well-covered graph is 1-well-covered if deletion of every vertex of the graph leaves it well-covered. It is known that a graph without isolated vertices is 1-well-covered if and only if every two disjoint independent sets are included in two disjoint maximum independent sets. Well-covered graphs are related to combinatorial commutative algebra (e.g., every Cohen-Macaulay graph is well-covered, while each Gorenstein graph without isolated vertices is 1-well-covered). Our intent is to construct several infinite families of 1-well-covered graphs using the following known graph operations: corona, join, and rooted product of graphs. Adopting some known techniques used to advantage for well-covered graphs, one can prove that: if the graph G has no isolated vertices, then the corona of G and H is 1-well-covered if and only if H is a complete graph of order two at least; the join of the graphs G and H is 1-well-covered if and only if G and H have the same independence number and both are 1-well-covered; if H satisfies the property that every three pairwise disjoint independent sets are included in three pairwise disjoint maximum independent sets, then the rooted product of G and H is 1-well-covered, for every graph G. These findings show not only how to generate some more families of 1-well-covered graphs, but also that, to this aim, sometimes, one may use graphs that are not necessarily 1-well-covered.

Keywords: maximum independent set, corona, concatenation, join, well-covered graph

Procedia PDF Downloads 205

Authors: Hilary Rutto, Linda Sibali

Abstract:

In these modern times, we constantly search for new and innovative technologies to lift the burden of our extreme energy demand. The overall purpose of biofuel production research is to source an alternative energy source to replace the normal use of fossil fuel as liquid petroleum products. This experiment looks at the basis of biodiesel production with regards to alternative catalysts that can be used to produce biodiesel. The key factors that will be addressed during the experiments will focus on temperature variation, catalyst additions to the overall reaction, methanol to oil ratio, and the impact of agitation on the reaction. Brine samples sources from nearby plants will be evaluated and tested thoroughly and the key characteristics of these brine samples analysed for the verification of its use as a possible catalyst in biodiesel production. The one factor at a time experimental approach was used in this experiment, and the recycle and reuse characteristics of the heterogeneous catalyst was evaluated.

Keywords: brine sludge, heterogenous catalyst, biodiesel, one factor

Procedia PDF Downloads 164

Authors: Chun-Chung Chen, Bo-Han Lee, Yu-Chi Sung

Abstract:

Monitoring the status of tensioning force of stay cables is a significant issue for the assessment of structural safety of extradosed bridges. Moreover, it is known that there is a high correlation between the existing tension force and the vibration frequencies of cables. This paper presents the characteristic of frequencies of stay cables of a field extradosed bridge by using vibration-based monitoring methods. The vibration frequencies of each stay cables were measured in stages from the beginning to the completion of bridge construction. The result shows that the vibration frequency variation trend of different lengths of cables at each measured stage is different. The observed feature can help the application of the bridge long-term monitoring system and contribute to the assessment of bridge safety.

Keywords: vibration-based method, extradosed bridges, bridge health monitoring, bridge stay cables

Procedia PDF Downloads 144

Authors: L. Mouzai, M. Bouhadef

Abstract:

Rills begin to be generated once overland flow shear capacity overcomes the soil surface resistance. This resistance depends on soil texture, the arrangement of soil particles and on chemical and physical properties. The rill density could affect soil erosion, especially when the distance between the rills (interrill) contributes to the variation of the rill characteristics, and consequently on sediment concentration. To investigate this point, agricultural sandy soil, a soil tray of 0.2x1x3m³ and a piece of hardwood rectangular in shape to build up rills were the base of this work. The results have shown that small lines have been developed between the rills and the flow acceleration increased in comparison to the flow on the flat surface (interrill). Sediment concentration increased with increasing rill number (density).

Keywords: artificial rainfall, experiments, rills, soil erosion, transport capacity

Procedia PDF Downloads 157

Authors: Ti-Jun Xiao, Zhe Xu

Abstract:

Controllability is one of the fundamental issues in control systems. In this paper, we study the controllability of second order evolutional control systems in Hilbert spaces with memory and boundary controls, which model dynamic behaviors of some viscoelastic materials. Transferring the control problem into a moment problem and showing the Riesz property of a family of functions related to Cauchy problems for some integrodifferential equations, we obtain a general boundary controllability theorem for these second order evolutional control systems. This controllability theorem is applicable to various concrete 1D viscoelastic systems and recovers some previous related results. It is worth noting that Riesz sequences can be used for numerical computations of the control functions and the identification of new Riesz sequence is of independent interest for the basis-function theory. Moreover, using the Riesz sequences, we obtain the existence and uniqueness of (weak) solutions to these second order evolutional control systems in Hilbert spaces. Finally, we derive the exact boundary controllability of a viscoelastic beam equation, as an application of our abstract theorem.

Keywords: evolutional control system, controllability, boundary control, existence and uniqueness

Procedia PDF Downloads 217

Authors: Allagui Mohamed

Abstract:

The study of the temporal variation of the PM10 and the SO₂ in the area of Sfax during the year of 2008, showed very significant fluctuations of the contents. They depend on the transmitting sources and the weather conditions. The study of the evolutionary behavior of the PM10 and the SO₂ in a situation of the Sirocco revealed the determining influence of the Sahara which was confirmed by its strong enrichment of the atmosphere with particulate matter. The analysis of a situation of breeze of sea highlighted the increase in the contents of the PM10 of agreement with the increase the speed of the marine wind, in particular for the diurnal period, possibly testifying to the enrichment of the aerosol in a considerable maritime component. A situation of anticyclonic winter examined when with it the accumulation of the contents of the PM10 at a rate of 70 μg/m³ showed such concentrations remained weak by comparison with other studies which show contents of about 300 μg/m³.

Keywords: PM10, sea breeze, SO₂, sirocco, anticyclone

Procedia PDF Downloads 123

Authors: Chien Chon Chen, Chun Mei Chu, Chuan Ju Wang, Chih Yuan Chen, Ker Jer Huang

Abstract:

Cesiumiodide with Na doping (CsI(Na)) solution or melt is easily forming three- dimension dendrites on the free surface. The defects or bobbles form inside the CsI(Na) during the solution or melt solidification. The defects or bobbles can further effect the x-ray path in the CsI(Na) crystal and decrease the scintillation characteristics of CsI(Na). In order to enhance the CsI(Na) scintillated property we made single crystal of CsI(Na) column in the anodic aluminum oxide (AAO) template by hydraulic pressure injection method. It is interesting that when CsI(Na) melt is confined in the small AAO channels, the column grow as stable single column without any dendrites. The high aspect ratio (100~10000) of AAO and nano to sub-micron channel structure which is a suitable template for single of crystal CsI(Na) formation. In this work, a new low-cost approach to fabricate scintillator crystals using anodic aluminum oxide (AAO) rather than Si is reported, which can produce scintillator crystals with a wide range of controllable size to optimize their performance in X-ray detection.

Keywords: cesiumiodide, AAO, scintillator, crystal, X-ray

Procedia PDF Downloads 457

Authors: Rajesh Bera, Durbadal Mandal, Rajib Kar, Sakti P. Ghoshal

Abstract:

This paper describes optimal thinning of an Elliptical Cylindrical Array (ECA) of uniformly excited isotropic antennas which can generate directive beam with minimum relative Side Lobe Level (SLL). The Particle Swarm Optimization (PSO) method, which represents a new approach for optimization problems in electromagnetic, is used in the optimization process. The PSO is used to determine the optimal set of ‘ON-OFF’ elements that provides a radiation pattern with maximum SLL reduction. Optimization is done without prefixing the value of First Null Beam Width (FNBW). The variation of SLL with element spacing of thinned array is also reported. Simulation results show that the number of array elements can be reduced by more than 50% of the total number of elements in the array with a simultaneous reduction in SLL to less than -27dB.

Keywords: thinned array, Particle Swarm Optimization, Elliptical Cylindrical Array, Side Lobe Label.

Procedia PDF Downloads 440

Authors: M. Szechynska-Hebda, M. Sobczak, E. Rozanska, J. Troczynska, Z. Banaszak, N. Hordyńska, M. Dyda, M. Wedzony

Abstract:

Chloroplasts, as essential organelles for photosynthesis, play a critical role in plant development. However, disturbances in the proper functioning of chloroplasts, in the extreme case manifesting as albinism of tissues and whole plants, are a phenomenon often occurring in conditions deviating from natural (e.g., in vitro cultures applied in breeding programs). Using whole-transcriptome analysis (RNA-Seq) together with light, fluorescent and electron microscopy, it was shown, that development of chloroplasts and formation of green or albino plants in the androgenesis process are genotype-dependent; however, they could be modulated by sub-optimal temperature treatment. The reprogramming of the microspore development from gametophytic to sporophytic, and then regeneration of green plant can be positively regulated by cold stress (4 ⁰C). A high temperature stress (32 ⁰C) can induce androgenesis, but it is a factor negatively influencing green plant regeneration (promoting albinism). A similar effect on microspores, androgenesis, and subsequent chloroplast formation, is elicited as a result of postponing the date of spike collection from spring to summer in field conditions (natural temperature rise). It is determined in both environmental or genotypic manner. The delay of the sowing date (environmental effect) or growing of late genotypes (genotypic effect) result in spike maturation at higher temperatures and significantly enhance albino plant formation in androgenesis process. Such a temperature system (4 ⁰C vs. 32 ⁰C) was used to study the chloroplast biogenesis process in wheat and triticale. It was shown, that efficiency of physiological processes differentiates microspore development during cold reprograming in genotypes susceptible and resistant to androgenesis. Moreover, a great variation in developmental stages of the microspores in one anther is observed for susceptible genotypes. Microspores that are more physiologically active under cold conditions can activate signaling pathways and processes, which provide an appropriate supply of metabolites to cell compartments. This, in turn, fully correlates with the genotype-dependent efficiency of chloroplast formation (or different types of plastid) at particular steps of androgenesis. The effect obtained after applying a high temperature stress is different. High temperature causes a significant acceleration of microspore development and less variation in developmental stages at the end of the treatment. Therefore, the developmental diversity of the microspores in one anther seems to be a critical factor for subsequent cell and chloroplast differentiation. The work was financed by Ministry of Agriculture and Rural Development within Program: 'Biological Progress in Plant Production', project no HOR.hn.802.15.2018

Keywords: androgenesis, chloroplast biogenesis, temperature stress, wheat

Procedia PDF Downloads 143

Authors: Mohamed Boualem Salah

Abstract:

The size and shape of soil particles reflect the formation history of the grains. In turn, the macro scale behavior of the soil mass results from particle level interactions which are affected by particle shape. Sphericity, roundness and smoothness characterize different scales associated to particle shape. New experimental data and data from previously published studies are gathered into two databases to explore the effects of particle shape on packing as well as small and large-strain properties of sandy soils. Data analysis shows that increased particle irregularity (angularity and/or eccentricity) leads to: an increase in emax and emin, a decrease in stiffness yet with increased sensitivity to the state of stress, an increase in compressibility under zero-lateral strain loading, and an increase in critical state friction angle φcs and intercept Γ with a weak effect on slope λ. Therefore, particle shape emerges as a significant soil index property that needs to be properly characterized and documented, particularly in clean sands and gravels. The systematic assessment of particle shape will lead to a better understanding of sand behavior.

Keywords: angularity, eccentricity, shape particle, behavior of soil

Procedia PDF Downloads 408

Authors: Richa Bhardwaj

Abstract:

Tecomella undulata (Sm.) Seem is a monotypic genus belonging to family Bignoniaceae. The plant holds tremendous potential of medicinal value and has been traditionally used in various ailments like syphilis, leukoderma, blood disorders to name a few. The plant has gained prominence due to the presence of some prominent secondary metabolites. The present study focuses on the GC-MS analysis of leaf extracts of T. undulata which revealed the presence of certain bioactive compounds like stigmasterol, sitosterol, thiazoline, phytol, pthalic acid, methyl alpha ketopalmitate and so forth. A total of about 20 bioactive compounds were identified from the leaf extract spectra. Antimicrobial activity of the leaf extract was assayed against pathogenic bacteria and fungi. The alkaloids from leaf extracts showed antimicrobial activity against E.coli and B.subtilis. The flavonoids from leaves showed positive activity against Penicillium species and Candida albicans. The study thus infers that the presence of bioactive components may be the principle behind the antimicrobial property of different plant parts and therefore Tecomella forms a potential plant for herbal drug formulation.

Keywords: Tecomella undulata, bioactive compounds, GC-MS, antimicrobial activity

Procedia PDF Downloads 143

Authors: Chahrazed Bendenia, Souhila Bendenia, Samia Moulebhar, Hanaa Merad-Dib, Sarra Merabet, Sid Ahmed Khantar, Baghdad Hadri

Abstract:

In recent years, organic solar cells (OSCs) have become the fundamental concern of researchers thanks to their advantages in terms of flexibility, manufacturing processes and low cost. The performance of these devices is influenced by various factors, such as the layers introduced in the stacking of the solar cell realized. In our work, the modeling of a reverse OSC under AM1.5G illumination will be determined. The photo-active polymer/fullerene layer will be analyzed from the polymer variation of this layer using the SCAPS simulator to extract the J-V characteristics: open circuit voltage (Voc), short circuit current (Jsc), filling factor (FF) and power conversion efficiency (η). The results obtained indicated that the materials used have a significant impact on improving the photovoltaic parameters of the devices studied.

Keywords: solar, polymer, simulator, characteristics

Procedia PDF Downloads 72

Authors: Parcha Sreenivasa Rao, P. Lakshmi

Abstract:

Diabetes Mellitus is metabolic disorder, characterized by high glucose levels in the blood due to one of the reason i.e., the death of β cells. The lack of β cells leads to the reduced insulin levels. The β cell death generally occurs due to apoptosis induced by the several cytokines. IL-1β, IFN- ϒ and TNF –α cytokines that are generally cause apoptosis to the β cell. The nutrient based apoptosis is generally seen with high glucose and free fatty acids. It is also noted that the β cell death triggered by Fas ligand and its receptor Fas at the surface of the activated CD8+ T- lymphocytes. Reports also reveal that the β cell apoptosis is under control of the transcription factors NF-kB and STAT- 1. The arresting or opposing of the β cell apoptosis can be overcome by the different growth factors like GLP-1, growth hormone, prolactin, VEGF, Dipeptidyl peptidase-4, Vildagliptin, suberoylanilidehydroxamic acid, trichistatin-A, XIAP, Bcl-2, FGF-21. Present investigation explains antiapoptotic property of the β cells derived from the mesenchymal stem cells of umbilical cord.

Keywords: stem cells, umblical cord, diabetes, apoptosis

Procedia PDF Downloads 376

Authors: Sanjay Narayan Deo, Badam Singh Kushvah

Abstract:

Bennu(101955) is a half kilometer potentially hazardous near-Earth asteroid. We analyze the influence of Yarkovsky effect and relativistic effect of the Sun on the motion of the asteroid Bennu. The transverse model is used to compute Yarkovsky force on asteroid Bennu. Our dynamical model includes Newtonian perturbations of eight planets, the Moon, the Sun and three massive asteroid (1Ceres, 2Palas and 4Vesta). We showed the variation in orbital elements of nominal orbit of the asteroid. In the presence of Yarkovsky effect, the Semi-major axis of the orbit of the asteroid is decreases by 350 m over one period of orbital motion. The magnitude of Yarkovsky force is computed. We find that maximum magnitude of Yarkovsky force is 0.09 N at the perihelion . We also found that the magnitude of the Sun relativity effect is greater than the Yarkovsky effect on the motion the asteroid Bennu.

Keywords: Bennu, orbital elements, relativistic effect, Yarkovsky effect

Procedia PDF Downloads 290

Authors: Fabian J. Manoppo, Dody M. J. Sumayouw

Abstract:

The bending moment of a single free head model flexible batter piles in sand under horizontal loads is investigated. The theoretical estimate of the magnitude maximum bending moment for the piles was considering a vertical rigid pile under an inclined load and using semi-empirical relations. The length of the equivalent rigid pile was based on the relative stiffness factor of the pile. Model tests were carried out using instrumented piles of wide-ranging flexibilities. The piles were buried in loose sand at batter angles of β=±150, β=±300 and were applied to incrementally increasing lateral loads. The pile capacities and the variation of bending moment along the pile shaft were measured. The new coefficient of 0.5 was proposed to estimate the bending moment of a flexible batter pile in the sand under horizontal.

Keywords: batter pile, bending moment, sand, horizontal loads

Procedia PDF Downloads 13

Authors: B. Benalioua, I. Benyamina, A. Bentouami, B. Boury

Abstract:

The objective of this study is based on the synthesis of a new photocatalyst based on TiO2 and its application in the photo-degradation of an acid dye under the visible light. The material obtained was characterized by different techniques like diffuse reflectance UV–Vis spectroscopy (DRS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The photocatalytic efficiency of the Bi, N co-doped TiO2 treated at 600°C for 1 h was tested on the Indigo Carmine under the irradiation of visible light and compared with that of the commercial titanium oxide TiO2-P25 (Degussa). The XRD characterization of the material Bi -N- TiO2 (600°C) revealed the presence of the anatase phase and the absence of the rutile phase in comparison of the TiO2 P25 diffractogram. Characterization by UV- visible diffuse reflection (DRS) material showed that the Bi-N-TiO2 exhibits redshift (move visible) relative to commercial titanium oxide TiO2-P25, this property promises a photocatalytic activity of Bi-N-TiO2 under visible light. Indeed, the efficiency of photocatalytic Bi-N-TiO2 as a visible light is shown by a complete discoloration of indigo carmine solution of 16 mg/L after 40 minutes, whereas with the P25-TiO2 discoloration is achieved after 90 minutes.

Keywords: POA, heterogeneous photocatalysis, TiO2, co-doping

Procedia PDF Downloads 376

Authors: Abderrahmane Hamdi, Julie Chalon, Benoit Dodin, Philippe Champagne

Abstract:

This research work concerns the synthesis of hydrophobic and self-cleaning coatings as an alternative to fluorine-based coatings used on glass. The developed, highly transparent coatings are produced by a chemical route (sol-gel method) using two silica-based precursors, hexamethyldisilazane and tetraethoxysilane (HMDS/TEOS). The addition of zinc oxide nanoparticles (ZnO NPs) within the gel provides a photocatalytic property to the final coating. The prepared gels were deposited on glass slides using different methods. The properties of the coatings were characterized by optical microscopy, scanning electron microscopy, UV-VIS-NIR spectrophotometer, and water contact angle method. The results show that the obtained coatings are homogeneous and have a hydrophobic character. In particular, after thermal treatment, the HMDS/TEOS@ZnO charged gel deposited on glass constitutes a coating capable of degrading methylene blue (MB) under UV irradiation. Optical transmission reaches more than 90% in most of the visible light spectrum. Synthetized coatings have also demonstrated their mechanical durability and self-cleaning ability.

Keywords: coating, durability, hydrophobicity, sol-gel, self-cleaning, transparence

Procedia PDF Downloads 158

Authors: Piyapat Chitpirom, Teerakiat Jareonsettasin, Chintida Vichitsophaphan

Abstract:

The Foundation of Virtuous Youth was established and supported by the Crown Property Bureau, with the intention to instill goodness in Thai youth. The Centre for Educational Psychology is one of the three units under the foundation. We aim to develop programmes that can be used to improve the quality of education in schools. Translation of the King’s message in keeping with the modern research from various sources, our team create 6 programmes: (1) Teacher-Student Relationship (2) Growth Mindset (3) Socratic Teaching (4) Peer Tutoring (5) Parental Involvement (6) Inclusion. After nine months of implementing the programmes in the schools, we found that there were more cooperation between student-student, teacher-student, teacher-parent, and student-parent and the school regained trust from the community. Our ideas were accepted well by the government as our director was promoted to be the Vice Minister of Education in order to implement our programmes into national education system. We consider that the key of our success is that we do practical things. We are still continuing, improving, and learning from our work with hope that the quality of Thai education will improve in near future.

Keywords: education reform, educational psychology, effective teaching, teacher-student relationship

Procedia PDF Downloads 425

Authors: Evans V. Mauda, Stefan H. Foord, Thinandavha C. Munyai

Abstract:

The greatest threat to biodiversity is a loss of habitat through landscape fragmentation and attrition. Land use changes are therefore among the most immediate drivers of species diversity. Urbanization and agriculture are the main drivers of habitat loss and transformation in the Savanna biomes of South Africa. Agricultural expansion and the intensification in particular, take place at the expense of biodiversity and will probably be the primary driver of biodiversity loss in this century. Arthropods show measurable behavioural responses to changing land mosaics at the smallest scale and heterogeneous environments are therefore predicted to support more complex and diverse biological assemblages. Ants are premier soil turners, channelers of energy and dominate insect fauna, while spiders are a mega-diverse group that can regulate other invertebrate populations. This study aims to quantify the response of these two taxa in a rural-urban mosaic of a rapidly developing communal area. The study took place in and around two villages in the north-eastern corner of South Africa. Two replicates for each of the dominant land use categories, viz. urban settlements, dryland cultivation and cattle rangelands, were set out in each of the villages and sampled during the dry and wet seasons for a total of 2 villages × 3 land use categories × 2 seasons = 24 assemblages. Local scale variables measured included vertical and horizontal habitat structure as well as structural and chemical composition of the soil. Ant richness was not affected by land use but local scale variables such as vertical vegetation structure (+) and leaf litter cover (+), although vegetation complexity at lower levels was negatively associated with ant richness. However, ant richness was largely shaped by regional and temporal processes invoking the importance of dispersal and historical processes. Spider species richness was mostly affected by land use and local conditions highlighting their landscape elements. Spider richness did not vary much between villages and across seasons and seems to be less dependent on context or history. There was a considerable amount of variation in spider richness that was not explained and this could be related to factors which were not measured in this study such as temperature and competition. For both ant and spider assemblages the constrained ordination explained 18 % of variation in these taxa. Three environmental variables (leaf litter cover, active carbon and rock cover) were important in explaining ant assemblage structure, while two (sand and leaf litter cover) were important for spider assemblage structure. This study highlights the importance of disturbance (land use activities) and leaf litter with the associated effects on ant and spider assemblages across the study area.

Keywords: ants, assemblages, biosphere, diversity, land use, spiders, urbanization

Procedia PDF Downloads 266

Authors: Khaing Yadana Swe, Lillie Dewan

Abstract:

At present, the cascade PID control is widely used to control the super-heating temperature (main steam temperature). As the main steam temperature has the characteristics of large inertia, large time-delay, and time varying, etc., conventional PID control strategy can not achieve good control performance. In order to overcome the bad performance and deficiencies of main steam temperature control system, Model Free Adaptive Control (MFAC) P cascade control system is proposed in this paper. By substituting MFAC in PID of the main control loop of the main steam temperature control, it can overcome time delays, non-linearity, disturbance and time variation.

Keywords: model-free adaptive control, cascade control, adaptive control, PID

Procedia PDF Downloads 599

Authors: Pauline Ribert, Gaelle Roudaut, Sebastien Dupont, Laurent Beney

Abstract:

Yeasts, anhydrobiotic organisms, can survive extreme water disturbances, thanks to the prolonged and reversible suspension of their cellular activity as well as the establishment of a defense arsenal. This property is exploited by many industrialists. One of the protection systems implemented by yeast is the vitrification of its cytoplasm by trehalose. The thermal resistance of dry yeasts is a crucial parameter for their use. However, studies on the thermal resistance of dry yeasts are often based on yeasts produced in laboratory conditions with non-optimal drying processes. We, therefore, propose a study on the thermal resistance of industrial dry yeasts in relation to their thermophysical properties. Heat stress was applied at three temperatures (50, 75, and 100°C) for 10, 30, or 60-minute treatments. The survival of yeasts to these treatments was estimated, and their thermophysical properties were studied by differential scanning calorimetry. The industrial dry yeasts resisted 60 minutes at 50°C and 75°C and 10 minutes at a temperature close to 100°C. At 100°C, yeast was above their glass transition temperature. Industrial dry yeasts are therefore capable of withstanding high thermal stress if maintained in a specific thermophysical state.

Keywords: dry yeast, glass transition, thermal resistance, vitrification

Procedia PDF Downloads 147