Search results for: accidents reduction
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5345

Search results for: accidents reduction

2375 NENU2PHAR: PHA-Based Materials from Micro-Algae for High-Volume Consumer Products

Authors: Enrique Moliner, Alba Lafarga, Isaac Herraiz, Evelina Castellana, Mihaela Mirea

Abstract:

NENU2PHAR (GA 887474) is an EU-funded project aimed at the development of polyhydroxyalkanoates (PHAs) from micro-algae. These biobased and biodegradable polymers are being tested and validated in different high-volume market applications including food packaging, cosmetic packaging, 3D printing filaments, agro-textiles and medical devices, counting on the support of key players like Danone, BEL Group, Sofradim or IFG. At the moment the project has achieved to produce PHAs from micro-algae with a cumulated yield around 17%, i.e. 1 kg PHAs produced from 5.8 kg micro-algae biomass, which in turn capture 11 kg CO₂ for growing up. These algae-based plastics can therefore offer the same environmental benefits than current bio-based plastics (reduction of greenhouse gas emissions and fossil resource depletion), using a 3rd generation biomass feedstock that avoids the competition with food and the environmental impacts of agricultural practices. The project is also dealing with other sustainability aspects like the ecodesign and life cycle assessment of the plastic products targeted, considering not only the use of the biobased plastics but also many other ecodesign strategies. This paper will present the main progresses and results achieved to date in the project.

Keywords: NENU2PHAR, Polyhydroxyalkanoates, micro-algae, biopolymer, ecodesign, life cycle assessment

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2374 Mixing Time: Influence on the Compressive Strength

Authors: J. Alvarez Muñoz, Dominguez Lepe J. A.

Abstract:

A suitable mixing time of the concrete, allows form a homogeneous mass, quality that leads to greater compressive strength and durability. Although there are recommendations as ASTM C94 standard these mention the time and the number of minimum and maximum speed for a ready-mix concrete of good quality, the specific behavior that would have a concrete mixed on site to variability of the mixing time is unknown. In this study was evaluated the behavior a design of mixture structural of f´c=250 kg/cm2, elaborate on site with limestone aggregate in warm sub-humid climate, subjected to different mixing times. Based on the recommendation for ready-mixed concrete ASTM C94, different times were set at 70, 90, 100, 110, 120, 140 total revolutions. A field study in which 14 works were observed where structural concrete made on site was used, allowed to set at 24 the number of revolutions to the reference mixture. For the production of concrete was used a hand feed concrete mixer with drum speed 28 RPM, the ratio w/c was 0.36 corrected, with a slump of 5-6 cm, for all mixtures. The compressive strength tests were performed at 3, 7, 14, and 28 days. The most outstanding results show increases in resistance in the mixtures of 24 to 70 revolutions between 8 and 17 percent and 70 to 90 revolutions of 3 to 8 percent. Increasing the number of revolutions at 110, 120 and 140, there was a reduction of the compressive strength of 0.5 to 8 percent. Regarding mixtures consistencies, they had a slump of 5 cm to 24, 70 and 90 rpm and less than 5 cm from 100 revolutions. Clearly, those made with more than 100 revolutions mixtures not only decrease the compressive strength but also the workability.

Keywords: compressive strength, concrete, mixing time, workability

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2373 Modelling Home Appliances for Energy Management System: Comparison of Simulation Results with Measurements

Authors: Aulon Shabani, Denis Panxhi, Orion Zavalani

Abstract:

This paper presents the modelling and development of a simulator for residential electrical appliances. The simulator is developed on MATLAB providing the possibility to analyze and simulate energy consumption of frequently used home appliances in Albania. Modelling of devices considers the impact of different factors, mentioning occupant behavior and climacteric conditions. Most devices are modeled as an electric circuit, and the electric energy consumption is estimated by the solutions of the guiding differential equations. The provided models refer to devices like a dishwasher, oven, water heater, air conditioners, light bulbs, television, refrigerator water, and pump. The proposed model allows us to simulate beforehand the energetic behavior of the largest consumption home devices to estimate peak consumption and improving its reduction. Simulated home prototype results are compared to real measurement of a considered typical home. Obtained results from simulator framework compared to monitored typical household using EmonTxV3 show the effectiveness of the proposed simulation. This conclusion will help for future simulation of a large group of typical household for a better understanding of peak consumption.

Keywords: electrical appliances, energy management, modelling, peak estimation, simulation, smart home

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2372 Radiation Emission from Ultra-Relativistic Plasma Electrons in Short-Pulse Laser Light Interactions

Authors: R. Ondarza-Rovira, T. J. M. Boyd

Abstract:

Intense femtosecond laser light incident on over-critical density plasmas has shown to emit a prolific number of high-order harmonics of the driver frequency, with spectra characterized by power-law decays Pm ~ m-p, where m denotes the harmonic order and p the spectral decay index. When the laser pulse is p-polarized, plasma effects do modify the harmonic spectrum, weakening the so-called universal decay with p=8/3 to p=5/3, or below. In this work, appeal is made to a single particle radiation model in support of the predictions from particle-in-cell (PIC) simulations. Using this numerical technique we further show that the emission radiated by electrons -that are relativistically accelerated by the laser field inside the plasma, after being expelled into vacuum, the so-called Brunel electrons is characterized not only by the plasma line but also by ultraviolet harmonic orders described by the 5/3 decay index. Results obtained from these simulations suggest that for ultra-relativistic light intensities, the spectral decay index is further reduced, with p now in the range 2/3 ≤ p ≤ 4/3. This reduction is indicative of a transition from the regime where Brunel-induced plasma radiation influences the spectrum to one dominated by bremsstrahlung emission from the Brunel electrons.

Keywords: ultra-relativistic, laser-plasma interactions, high-order harmonic emission, radiation, spectrum

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2371 Effect of Corrosion on the Shear Buckling Strength

Authors: Myoung-Jin Lee, Sung-Jin Lee, Young-Kon Park, Jin-Wook Kim, Bo-Kyoung Kim, Song-Hun Chong, Sun-Ii Kim

Abstract:

The ability to resist the shear strength arises mainly from the web panel of steel girders and as such, the shear buckling strength of these girders has been extensively investigated. For example, Blaser’s reported that when buckling occurs, the tension field has an effect after the buckling strength of the steel is reached. The findings of these studies have been applied by AASHTO, AISC, and to the European Code that provides guidelines for designs aimed at preventing shear buckling. Steel girders are susceptible to corrosion resulting from exposure to natural elements such as rainfall, humidity, and temperature. This corrosion leads to a reduction in the size of the web panel section, thereby resulting in a decrease in the shear strength. The decrease in the panel section has a significant effect on the maintenance section of the bridge. However, in most conventional designs, the influence of corrosion is overlooked during the calculation of the shear buckling strength and hence over-design is common. Therefore, in this study, a steel girder with an A/D of 1:1, as well as a 6-mm-, 16-mm-, and 12-mm-thick web panel, flange, and intermediate reinforcing material, respectively, were used. The total length was set to that (3200 mm) of the default model. The effect of corrosion shear buckling was investigated by determining the volume amount of corrosion, shape of the erosion patterns, and the angular change in the tensile field of the shear buckling strength. This study provides the basic data that will enable designs that incorporate values closer (than those used in most conventional designs) to the actual shear buckling strength.

Keywords: corrosion, shear buckling strength, steel girder, shear strength

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2370 Using Shape Memory Alloys for Structural Engineering Applications

Authors: Donatello Cardone

Abstract:

Shape memory alloys (SMAs) have great potential for use in the field of civil engineering. The author of this manuscript has been involved, since 1996, in several experimental and theoretical studies on the application of SMAs in structural engineering, within national and international research projects. This paper provides an overview of the main results achieved, including the conceptual design, implementation, and testing of different SMA-based devices, namely: (i) energy-dissipating braces for RC buildings, (ii) seismic isolation devices for buildings and bridges, (iii) smart tie-rods for arches and vaults and (iv) seismic restrainers for bridges. The main advantages of using SMA-based devices in the seismic protection of structures derive from the double-flag shape of their hysteresis loops, which implies three favourable features, i.e., self-centering capability, good energy dissipation capability, and high stiffness for small displacements. The main advantages of SMA-based units for steel tie-rods are associated with the thermal behaviour of superelastic SMAs, which is antagonistic compared to that of steel. This implies a strong reduction of force changes due to air temperature variations. Finally, SMA-based seismic restrainers proved to be effective in preventing bridge deck unseating and pounding.

Keywords: seismic protection of structures, shape memory alloys, structural engineering, steel tie-rods, seismic restrainers for bridges

Procedia PDF Downloads 98
2369 An Innovation and Development System for a New Hybrid Composite Technology in Aerospace Industry

Authors: M. Fette, J. P. Wulfsberg, A. Herrmann, R. H. Ladstaetter

Abstract:

Present and future lightweight design represents an important key to successful implementation of energy-saving, fuel-efficient and environmentally friendly means of transport in the aerospace and automotive industry. In this context the use of carbon fibre reinforced plastics (CFRP) which are distinguished by their outstanding mechanical properties at relatively low weight, promise significant improvements. Due to the reduction of the total mass, with the resulting lowered fuel or energy consumption and CO2 emissions during the operational phase, commercial aircraft and future vehicles will increasingly be made of CFRP. An auspicious technology for the efficient and economic production of high performance thermoset composites and hybrid structures for future lightweight applications is the combination of carbon fibre sheet moulding compound (SMC), tailored continuous carbon fibre reinforcements and metallic components in a one-shot pressing and curing process. This paper deals with a new hybrid composite technology for aerospace industries, which was developed with the help of a universal innovation and development system. This system supports the management of idea generation, the methodical development of innovative technologies and the achievement of the industrial readiness of these technologies.

Keywords: development system, hybrid composite, innovation system, prepreg, sheet moulding compound

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2368 Reduction Behavior of Some Low-Grade Iron Ores for Application in Blast Furnace

Authors: Heba Al-Kelesh

Abstract:

Day after day, high-grade iron ores are consumed. Because of the strong global demand for iron and steel, it has necessitated the utilization of various low-grade iron ores, which are not suitable for direct exploitation in the iron industry. The low-grade ores cannot be dressed using traditional mineral processing methods because of complicated mineral compositions. The present work is aimed to investigate the reducibility of some Egyptian iron ores and concentrates by conditions emulate different blast furnace areas. Representative specimens are collected from El-Gedida–Baharia oasis, Eastern South Aswan, and Eastern desert-wadi Kareem (EDC). Some mineralogical and morphological characterizations are executed. The reactivity arrangement of green samples is Baharia>Aswan>EDC. The presence of magnetite decreased reactivity of EDC. The reducibility of the Aswan sample is lower than Baharia due to the presence of agglomerated metallic grain surrounded by semi-melted phases. Specimens are annealed at 1000ᵒC for 3 hours. After firing, the reducibility of Aswan becomes the lowest due to the formation of fayalite and calcium phosphate phases. The relative attitude for green and fired samples reduced at different conditions are studied. For thermal and top areas, the reactivity of fired samples is greater than green ones, which were confirmed by morphological examinations.

Keywords: reducibility, low grade, iron industry, blast furnace

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2367 Pathways and Mechanisms of Lymphocytes Emigration from Newborn Thymus

Authors: Olena Grygorieva

Abstract:

Nowadays mechanisms of thymocytes emigration from the thymus to the periphery are investigated actively. We have proposed a hypothesis of thymocytes’ migration from the thymus through lymphatic vessels during periodical short-term local edema. By morphological, hystochemical methods we have examined quantity of lymphocytes, epitelioreticulocytes, mast cells, blood and lymphatic vessels in morpho-functional areas of rats’ thymuses during the first week after birth in 4 hours interval. In newborn and beginning from 8 hour after birth every 12 hours specific density of the thymus, absolute quantity of microcirculatory vessels, especially of lymphatic ones, lymphcyte-epithelial index, quantity of mast cells and their degranulative forms increase. Structure of extracellular matrix, intrathymical microenvironment and lymphocytes’ adhesive properties change. Absolute quantity of small lymphocytes in thymic cortex changes wavy. All these changes are straightly expressed from 0 till 2, from 12 till 16, from 108 till 120 hours of postnatal life. During this periods paravasal lymphatic vessels are stuffed with lymphocytes, i.e. discrete migration of lymphocytes from the thymus occurs. After rapid edema reduction, quantity of lymphatic vessels decrease, they become empty. Therefore, in the thymus of newborn periodical short-term local edema is observed, on its top discrete migration of lymphocytes from the thymus occurs.

Keywords: lymphocytes, lymphatic vessels, mast cells, thymus

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2366 Suicide in Late-Life Major Depressive Disorder: A Review of Structural and Functional Neuroimaging Studies

Authors: Wenqiu Cao

Abstract:

Suicide prevention is a global problem that needs to be taken seriously. Investigating the mechanisms of suicide in major depressive disorder (MDD) separately through neuroimaging technology is essential for effective suicide prevention. And it’s particularly urgent in geriatric depressive patients since older adults are more likely to use rapidly deadly means, and suicidal behavior is more lethal for older adults. The current study reviews five studies related to suicide in geriatric MDD that uses neuroimaging methodology in order to analyze the relevant neurobiological mechanisms. The majority of the studies found significant white matter and grey matter reduction or lesion widespread in multiple brain regions, including the frontal and parietal regions, the midbrain, the external capsule, and the cerebellum. Regarding the cognitive impairment in geriatric MDD, the reward signals were found weakened in the paralimbic cortex. The functional magnetic resonance imaging (fMRI) studies also found hemodynamic changes in the right dorsolateral prefrontal cortex (DLPFC), orbitofrontal cortex (OFC), and right frontopolar cortex (FPC) regions in late-life MDD patients with suicidal ideation. Future studies should consider the age of depression onset, more accurate measurements of suicide, larger sample size, and longitudinal design.

Keywords: brain imaging, geriatric major depressive disorder, suicidality, suicide

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2365 Polyampholytic Resins: Advances in Ion Exchanging Properties

Authors: N. P. G. N. Chandrasekara, R. M. Pashley

Abstract:

Ion exchange (IEX) resins are commonly available as cationic or anionic resins but not as polyampholytic resins. This is probably because sequential acid and base washing cannot produce complete regeneration of polyampholytic resins with chemically attached anionic and cationic groups in close proximity. The ‘Sirotherm’ process, developed by the Commonwealth Scientific and Industrial Research Organization (CSIRO) in Melbourne, Australia was originally based on the use of a physical mixture of weakly basic (WB) and weakly acidic (WA) ion-exchange resin beads. These resins were regenerated thermally and they were capable of removing salts from an aqueous solution at higher temperatures compared to the salt sorbed at ambient temperatures with a significant reduction of the sorption capacity with increasing temperature. A new process for the efficient regeneration of mixed bead resins using ammonium bicarbonate with heat was studied recently and this chemical/thermal regeneration technique has the capability for completely regenerating polyampholytic resins. Even so, the low IEX capacities of polyampholytic resins restrict their commercial applications. Recently, we have established another novel process for increasing the IEX capacity of a typical polyampholytic resin. In this paper we will discuss the chemical/thermal regeneration of a polyampholytic (WA/WB) resin and a novel process for enhancing its ion exchange capacity, by increasing its internal pore area. We also show how effective this method is for completely recycled regeneration, with the potential of substantially reducing chemical waste.

Keywords: capacity, ion exchange, polyampholytic resin, regeneration

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2364 Environmental Impact Assessment Methodology of the Tirana–Elbasan Road Project

Authors: Aurora Cerri, Niko Pollojani

Abstract:

The Tirana – Elbasan Road project is the most important highway project in Albania, constructed in the period May 2011 - ongoing. This project included construction of 38 km highway category road including 2.6 km of tunnel. It serves as a corridor connecting the Tirana, Capital of Albania and South-East area, and in the near future it is expected to continue in the direction of Macedonian border. Environmental Impact Assesment procedure for this project is provided by the Albanian Environmental Law No. 10431. This law establishes the regulation of procedures for identifying, assessment and reporting on the effects of certain projects on the environment, and the associated administrative procedures, during the decision-making process by the Ministry of Environment and Tourism for issuing environmental permit, and ensures that all relevant information concerning the environment are provided and considered. Due to the nature and size of the project, during the environmental impact assessment process, the European Union legislation, namely the EIA Directive 85/337 / EEC is considered. Moreover, in some cases, due to the lack of national standards and practical guidelines, when necessary those of EU member countries are considered. This paper presents an analysis of the EIA procedure followed on ‘Tirana – Elbasan’ Road project, with a focus on the application of the main stages of the procedure such as: screening, scoping, review, the EIA report; and consideration of alternatives, measures for impact prevention and reduction, and the public hearing T/discussion.

Keywords: highway, environmental impact assesment, Tirana, prevention

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2363 A Neural Network Classifier for Estimation of the Degree of Infestation by Late Blight on Tomato Leaves

Authors: Gizelle K. Vianna, Gabriel V. Cunha, Gustavo S. Oliveira

Abstract:

Foliage diseases in plants can cause a reduction in both quality and quantity of agricultural production. Intelligent detection of plant diseases is an essential research topic as it may help monitoring large fields of crops by automatically detecting the symptoms of foliage diseases. This work investigates ways to recognize the late blight disease from the analysis of tomato digital images, collected directly from the field. A pair of multilayer perceptron neural network analyzes the digital images, using data from both RGB and HSL color models, and classifies each image pixel. One neural network is responsible for the identification of healthy regions of the tomato leaf, while the other identifies the injured regions. The outputs of both networks are combined to generate the final classification of each pixel from the image and the pixel classes are used to repaint the original tomato images by using a color representation that highlights the injuries on the plant. The new images will have only green, red or black pixels, if they came from healthy or injured portions of the leaf, or from the background of the image, respectively. The system presented an accuracy of 97% in detection and estimation of the level of damage on the tomato leaves caused by late blight.

Keywords: artificial neural networks, digital image processing, pattern recognition, phytosanitary

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2362 The Relationship Between The Two-spatial World And The Decrease In The Area Of Commercial Properties

Authors: Syedhossein Vakili

Abstract:

According to the opinion of some experts, the world's two-spatialization means the establishment of a new virtual space and placing this new space next to the physical space. This dualization of space has left various effects, one of which is reducing the need for buildings and making the area of business premises economical through the use of virtual space instead of a part of physical space. In such a way that before the virtual space was known, a commercial or educational institution had to block a large part of its capital to acquire physical spaces and buildings in order to provide physical space and places needed for daily activities, but today, Thanks to the addition of the virtual space to the physical space, it has been possible to carry out its activities more widely in a limited environment with a minimum of physical space and drastically reduce costs. In order to understand the impact of virtual space on the reduction of physical space, the researcher used the official reports of the countries regarding the average area mentioned in the permits for the construction of commercial and educational units in the period from 2014 to 2023 and compared the average capital required for the absolute physical period with The period of two-spatialization of the world in the mentioned ten-year period, while using the analytical and comparative method, has proven that virtual space has greatly reduced the amount of investment of business owners to provide the required place for their activities by reducing the need for physical space. And economically, it has made commercial activities more profitable.

Keywords: two spatialization, building area, cyberspace, physical space, virtual place

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2361 Arteriosclerosis and Periodontitis: Correlation Expressed in the Amount of Fibrinogen in Blood

Authors: Nevila Alliu, Saimir Heta, Ilma Robo, Vera Ostreni

Abstract:

Periodontitis as an oral pathology caused by specific bacterial flora functions as a focal infection for the onset and aggravation of arteriosclerosis. These two distant pathologies, since they affect organs at a distance from each other, communicate with each other with correlation at the level of markers of inflammation in the blood. Fluctuations in the level of fibrinogen in the blood, depending on the active or passive phase of the existing periodontitis, affect the promotion of arteriosclerosis. The study is of the review type to analyze the effect of non-surgical periodontal treatment on fluctuations in the level of fibrinogen in the blood. The reduction of fibrinogen levels in the blood after non-surgical periodontal treatment of periodontitis in the patient's cavity is visible data and supported by literature sources. Also, the influence of a high amount of fibrinogen in the blood on the occurrence of arteriosclerosis is also another important data that again relies on many sources of literature. Conclusions: Thromboembolism and arteriosclerosis, as risk factors expressed in clinical data, have temporary bacteremia in the blood, which can occur significantly and often between phases of non-surgical periodontal treatment of periodontitis, treatments performed with treatment phases and protocols of predetermined treatment. Arterial thromboembolism has a significant factor, such as high levels of fibrinogen in the blood, which are significantly reduced during the period of non-surgical periodontal treatment.

Keywords: fibrinogen, refractory periodontitis, atherosclerosis, non-surgical, periodontal treatment

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2360 Flexural Fatigue Performance of Self-Compacting Fibre Reinforced Concrete

Authors: Surinder Pal Singh, Sanjay Goel

Abstract:

The paper presents results of an investigation conducted to study the flexural fatigue characteristics of Self Compacting Concrete (SCC) and Self Compacting Fibre Reinforced Concrete (SCFRC). In total 360 flexural fatigue tests and 270 static flexural strength tests were conducted on SCC and SCFRC specimens to obtain the fatigue test data. The variability in the distribution of fatigue life of SCC and SCFRC have been analyzed and compared with that of NVC and NVFRC containing steel fibres of comparable size and shape. The experimental coefficients of fatigue equations have been estimated to represent relationship between stress level (S) and fatigue life (N) for SCC and SCFRC containing different fibre volume fractions. The probability of failure (Pf) has been incorporated in S-N relationships to obtain families of S-N-Pf relationships. A good agreement between the predicted curves and those obtained from the test data has been observed. The fatigue performance of SCC and SCFRC has been evaluated in terms of two-million cycles fatigue strength/endurance limit. The theoretic fatigue lives were also estimated using single-log fatigue equation for 10% probability of failure to estimate the enhanced extent of theoretic fatigue lives of SCFRC with reference to SCC and NVC. The reduction in variability in the fatigue life, increased endurance limit and increased theoretiac fatigue lives demonstrates an overall better fatigue performance for SCC and SCFRC.

Keywords: fatigue life, fibre, probability of failure, self-compacting concrete

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2359 Promoting Psychosocial Intervention in Social Work to Manage Intersectional Stigma among Sexual Minorities during COVID-19 Pandemic in Uganda: Implications for Social Work Practice

Authors: Simon Mwima, Kasule Solomon Kibirige, Evans Jennifer Mann, Bosco Mukuba, Edson Chipalo, Agnes Nzomene, Eusebius Small, Moses Okumu

Abstract:

Introduction: Social workers must create, implement, and evaluate client-centered psychosocial interventions (CCPI) to reduce the impact of intersectional stigma on HIV service utilization among sexual minorities. We contribute to the scarcity of evidence about sexual minorities in Uganda by using social support theory to explore clients' perceptions that shape CCPI. Based on Focused Group Discussion (FGD) with 31 adolescents recruited from Kampala's HIV clinics in 2021, our findings reveal the positive influence of instrumental, informational, esteem, emotional, and social network support as intersectional stigma reduction interventions. Men who have sex with men, lesbians, and bisexual women used such strategies to navigate a heavily criminalized and stigmatizing setting during the COVID-19 pandemic in Uganda. Conclusion: This study provides evidence for the social work profession to develop and implement psychosocial interventions that reduce HIV stigma and discrimination among MSM, lesbians, and bisexual young people living with HIV in Uganda.

Keywords: pyschosocial interventions, social work, intersectional stigma, HIV/AIDS, adolescents, sexual minorities, Uganda

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2358 Models to Calculate Lattice Spacing, Melting Point and Lattice Thermal Expansion of Ga₂Se₃ Nanoparticles

Authors: Mustafa Saeed Omar

Abstract:

The formula which contains the maximum increase of mean bond length, melting entropy and critical particle radius is used to calculate lattice volume in nanoscale size crystals of Ga₂Se₃. This compound belongs to the binary group of III₂VI₃. The critical radius is calculated from the values of the first surface atomic layer height which is equal to 0.336nm. The size-dependent mean bond length is calculated by using an equation-free from fitting parameters. The size-dependent lattice parameter then is accordingly used to calculate the size-dependent lattice volume. The lattice size in the nanoscale region increases to about 77.6 A³, which is up to four times of its bulk state value 19.97 A³. From the values of the nanosize scale dependence of lattice volume, the nanoscale size dependence of melting temperatures is calculated. The melting temperature decreases with the nanoparticles size reduction, it becomes zero when the radius reaches to its critical value. Bulk melting temperature for Ga₂Se₃, for example, has values of 1293 K. From the size-dependent melting temperature and mean bond length, the size-dependent lattice thermal expansion is calculated. Lattice thermal expansion decreases with the decrease of nanoparticles size and reaches to its minimum value as the radius drops down to about 5nm.

Keywords: Ga₂Se₃, lattice volume, lattice thermal expansion, melting point, nanoparticles

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2357 Coupled Analysis for Hazard Modelling of Debris Flow Due to Extreme Rainfall

Authors: N. V. Nikhil, S. R. Lee, Do Won Park

Abstract:

Korean peninsula receives about two third of the annual rainfall during summer season. The extreme rainfall pattern due to typhoon and heavy rainfall results in severe mountain disasters among which 55% of them are debris flows, a major natural hazard especially when occurring around major settlement areas. The basic mechanism underlined for this kind of failure is the unsaturated shallow slope failure by reduction of matric suction due to infiltration of water and liquefaction of the failed mass due to generation of positive pore water pressure leading to abrupt loss of strength and commencement of flow. However only an empirical model cannot simulate this complex mechanism. Hence, we have employed an empirical-physical based approach for hazard analysis of debris flow using TRIGRS, a debris flow initiation criteria and DAN3D in mountain Woonmyun, South Korea. Debris flow initiation criteria is required to discern the potential landslides which can transform into debris flow. DAN-3D, being a new model, does not have the calibrated values of rheology parameters for Korean conditions. Thus, in our analysis we have used the recent 2011 debris flow event in mountain Woonmyun san for calibration of both TRIGRS model and DAN-3D, thereafter identifying and predicting the debris flow initiation points, path, run out velocity, and area of spreading for future extreme rainfall based scenarios.

Keywords: debris flow, DAN-3D, extreme rainfall, hazard analysis

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2356 Oral Biofilm and Stomatitis Denture: Local Implications and Cardiovascular Risks

Authors: Adriana B. Ribeiro, Camila B. Araujo, Frank L. Bueno, Luiz Eduardo V. Silva, Caroline V. Fortes, Helio C. Salgado, Rubens Fazan Jr., Claudia H. L. da Silva

Abstract:

Denture-related stomatitis (DRS) has recently been associated with deleterious cardiovascular effects, including hypertension. This study evaluated salivary parameters, blood pressure (BP) and heart rate variability (HRV), before and after DRS treatment in edentulous patients (n=14). Collection of unstimulated and stimulated saliva, as well as blood pressure (BP) measurements and electrocardiogram recordings were performed before and after 10 days of DRS treatment. The salivary flow (mL/min) was found similar at both times while pH was smaller (more neutral) after treatment (7.3 ± 2.2 vs. 7.1 ± 0.24). Systolic BP (mmHg) showed a trend, but not a significant reduction after DRS treatment (158 ± 25.68 vs. 148 ± 16,72, p=0,062) while diastolic BP was found similar in both times (86 ± 13.93 and 84 ± 9.38). Overall HRV, measured by standard deviation of RR intervals was not affected by DRS treatment (24 ± 4 vs 18 ± 2 ms), but differences of successive RR intervals (an index of parasympathetic cardiac modulation) increased after the treatment (26 ± 4 vs 19 ± 2 ms). Moreover, another index of vagal modulation of the heart, the power of RR interval spectra at high-frequency, was also markedly higher after DRS treatment (236 ± 63 vs 135 ± 32 ms²). Such findings strongly suggest that DRS is linked to an autonomic imbalance with sympathetic overactivity, which is markedly deleterious, increasing cardiovascular risk and the incidence of diseases such as hypertension. Acknowledgment: This study is supported by FAPESP, CNPq.

Keywords: biofilm, denture stomatitis, HRV, blood pressure

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2355 An Assessment of Entrepreneurial Landscape in Sub-Saharan Africa

Authors: Abubakar Salisu Garba

Abstract:

The objective of the paper is to highlight the nature of entrepreneurial activities in the Sub Sahara Africa. Five countries in the Sub Sahara African that are participating in Global Entrepreneurship Monitor (GEM) research have been studied to understand the types of entrepreneurial activities and their socio-economic implications in the region. The importance of entrepreneurial activities in boosting socio-economic development has been recognized not only in developing countries, but across the entire global economies. Some people believe that the wealth and poverty of developing countries is associated with nature and type of entrepreneurial activity. Policy makers are not only concern about the rate of business start up, but the growth and development of those starts up is of paramount importance to the development of the country’s economy. Although, the supply of entrepreneurs is essential, sometimes it does not really matters in boosting economic performance. What is more important is having high impact entrepreneurs who could make meaningful contribution to the economy. High growth oriented entrepreneurs are more stable and contribute greatly in enhancing the economic performance. When entrepreneurs are facing difficulties in sustaining and growing their businesses, it may be unlikely for entrepreneurship to reduce unemployment and poverty. Inadequate financial supports, insufficient infrastructure, lack of enforcing laws protecting the right of entrepreneurs are some of the problems making business environment difficult in Sub-Saharan Africa.

Keywords: entrepreneurship, entrepreneurial activity, job creation, poverty reduction, Sub-Saharan Africa

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2354 Energy Conservation Strategies of Buildings in Hot, Arid Region: Al-Khobar, Saudi Arabia

Authors: M. H. Shwehdi, S. Raja Mohammad

Abstract:

Recently energy savings have become more pronounced as a result of the world financial crises as well the unstable oil prices. Certainly all entities needs to adapt Energy Conservation and Management Strategies due to high monthly consumption of their spread locations and advancements of its telecom systems. These system improvements necessitate the establishment of more exchange centers as well provide energy savings. This paper investigates the impact of HVAC System Characteristics, Operational Strategies, the impact of Envelope Thermal Characteristics, and energy conservation measures. These are classified under three types of measures i.e. Zero-Investment; Low-Investment and High-Investment Energy Conservation Measures. The study shows that the Energy Conservation Measures (ECMs) pertaining to the HVAC system characteristics and operation represent the highest potential for energy reduction, attention should be given to window thermal and solar radiation characteristics when large window areas are used. The type of glazing system needs to be carefully considered in the early design phase of future buildings. Paper will present the thermal optimization of different size centers in the two hot-dry and hot-humid Saudi Arabian city of Al Khobar, East province.

Keywords: energy conservation, optimization, thermal design, intermittent operation, exchange centers, hot-humid climate, Saudi Arabia

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2353 Applying the Extreme-Based Teaching Model in Post-Secondary Online Classroom Setting: A Field Experiment

Authors: Leon Pan

Abstract:

The first programming course within post-secondary education has long been recognized as a challenging endeavor for both educators and students alike. Historically, these courses have exhibited high failure rates and a notable number of dropouts. Instructors often lament students' lack of effort in their coursework, and students often express frustration that the teaching methods employed are not effective. Drawing inspiration from the successful principles of Extreme Programming, this study introduces an approach—the Extremes-based teaching model — aimed at enhancing the teaching of introductory programming courses. To empirically determine the effectiveness of the model, a comparison was made between a section taught using the extreme-based model and another utilizing traditional teaching methods. Notably, the extreme-based teaching class required students to work collaboratively on projects while also demanding continuous assessment and performance enhancement within groups. This paper details the application of the extreme-based model within the post-secondary online classroom context and presents the compelling results that emphasize its effectiveness in advancing the teaching and learning experiences. The extreme-based model led to a significant increase of 13.46 points in the weighted total average and a commendable 10% reduction in the failure rate.

Keywords: extreme-based teaching model, innovative pedagogical methods, project-based learning, team-based learning

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2352 Effects of Aerobic Training on MicroRNA Let-7a Expression and Levels of Tumor Tissue IL-6 in Mice With Breast Cancer

Authors: Leila Anoosheh

Abstract:

Aim: The aim of this study was to assess The effects of aerobic training on microRNA let-7a expression and levels of tumor tissue IL-6 in mice with breast cancer. Method: Twenty BALB/c c mice (4-5 weeks,17 gr mass) were cancerous by injection of estrogen-dependent receptor breast cancer cells MC4-L2 and divided into two groups: tumor-training(TT) and tumor-control(TC) group. Then TT group completed aerobic training for 6 weeks, 5 days per week (14-18 m/min). After tumor emersion, tumor width and length were measured by digital caliper every week. 48 hours after the last exercise subjects were killed. Tissue sampling were collected and stored in -70ᵒ. Tumor tissue was homogenized and let-7a expression and IL-6 levels were accounted with Real time-PCR and ELISA Kit respectively. Statistical analysis of let-7a was conducted by the REST software. Repeated measures and independent tests were used to assess tumor size and IL-6, respectively. Results: Tumor size and IL-6 levels were significantly decreased in TT group compare with TC group (p<0.05). microRNA let-7a was increased significantly in TT against control group respectively (p=0/000). Conclusion: Reduction in tumor size, followed by aerobic exercise can be attributed to the loss of inflammatory factors such as IL-6; It seems that regarding to up regulation effects of aerobic exercise training on let-7a and down regulation effects of that on IL-6 in mice with breast cancer, This type of training can be used as adjuvant therapy in conjunction with other therapies for breast cancer.

Keywords: breast cancer, aerobic training, microRNA let-7a, IL-6

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2351 The Effect of Proper Drainage on the Cost of Building and Repairing Roads

Authors: Seyed Abbas Tabatabaei, Saeid Amini, Hamid Reza Ghafouri

Abstract:

One of the most important factors in flexible pavement failure is the lack of proper drainage along the roads. Water on the Paving Systems is one of the main parameters of pavement failure. Though, if water is discharged without delay and prior to discharge in order to prevent damaging the pavement the lifetime of the pavement will be considerably increased. In this study, duration of water stay and materials properties in pavement systems and the effects of aggregate gradation, and hydraulic conductivity of the drainage rate and Effects of subsurface drainage systems, drainage and reduction in the lifetime of the pavement have been studied. The study conducted in accordance with the terms offered can be concluded as under. The more hydraulic conductivity the less drainage time and the use of sub-surface drainage system causes two to three times of the pavement lifetime. In this research it has been tried by study and calculate the drained and undrained pavements lifetime by considering the effectiveness of water and drainage coefficient on flexible materials modulus and by using KENLAYER software to compare the present value cost of these pavements has been paid for a 20 year lifetime design. In this study, 14 pavement sections have been considered, of which 7 sections have been drained and 7 other not. Results show that drained pavements have more initial costs but the failure severity is so little in them and have longer lifetime for a 20 year lifetime design, the drained pavements seem so economic.

Keywords: drainage, base and sub-base, elasticity modulus, aggregation

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2350 Evaluation of the Effectiveness of the Argon Plasma Jet on Healing Process of the Wagner Grade 2 Diabetic Foot Ulcer

Authors: M. Khaledi Pour, P. Akbartehrani, M. Amini, M. Khani, M. Mohajeri Tehrani, R. Radi, B. Shokri

Abstract:

Diabetic Foot Ulcer (DFU) is one of the costly severe complications of diabetes. Neuropathy and Peripheral Arterial Disease (PAD) due to diabetes are significant causes of this complication. In 10 years the patients with DFUs are twice as likely to die as patients without DFUs. Cold Atmospheric Plasma (CAP) is a promising tool for medical purposes. CAP generate reactive species at room temperature and are effective in killing bacteria and fibroblast proliferation. These CAP-based tools produce NO, which has bactericidal and angiogenesis properties. It also showed promising effects in the DFUs surface reduction and the time to wound closure. In this paper, we evaluated the effect of the Argon Plasma Jet (APJ) on the healing process of the Wagner Grade 2 DFUs in a randomized clinical trial. The 20 kHz sinusoidal voltage frequency derives the APJ. Patients (n=20) were randomly double-blinded assigned into two groups. These groups receive the standard care (SC, n=10) and the standard care with APJ treatment (SC+APJ, n=10) for five sessions in four weeks. The results showed that the APJ treatment along standard care could reduce the wound surface by 20 percent more than the standard care. Also, It showed a more influential role in controlling wound infection.

Keywords: argon plasma jet, cold atmospheric plasma, diabetes, diabetic foot ulcer

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2349 In vivo Anti-inflammatory, Analgesic, and Antipyretic Activities of Aqueous Extract of Leaves of Brocchia cinerea (Vis.)

Authors: Nisrine Chlif, Mohammed Diouri, Amar Bentayeb

Abstract:

Background: The Leaves of Brocchia cinerea (Vis.) (Asteraceae) is used traditionally and ethnomedicinally to alleviate pain, fever, and inflammation conditions. Objective: The current study investigates the anti-inflammatory, analgesic, and antipyretic activities of aqueous extract of the leaves of Brocchia cinerea (LBC). Material and methods: The extract was screened for anti-inflammatory (carrageenan-induced paw edema) and analgesic (acetic acid-induced writhing) activities in Wistar rats. Before acetic acid or carrageenan injection, rats were orally fed LBC (200 and 400 mg/ kg), Indomethacin (10 mg/kg), or Aspirin (100 mg/kg). The antipyretic effect was studied in brewer’s yeast-induced pyrexia model in rats using Paracetamol (100 mg/kg) as a standard drug. Results: The crude extract tested significantly prevented the increase in paw volume as compared to the control at 200 mg/kg and 400 mg/kg. The LBC treatment significantly inhibited pain at 400 mg/kg with a percent inhibition of 55.82%, as well as showing a significant reduction in hyperpyrexia in rats at 400 mg/kg. LBC extract produced a comparable activity to paracetamol at 100 mg/kg (p <0.01). Conclusion: The results of the present study that the leaves of B. cinerea extract exhibited strongly anti-inflammatory, analgesic, and antipyretic properties and justify the traditional use of this plant in inflammation, pain, and fever.

Keywords: analgesic, anti-inflammation, antipyretic, brocchia cinerea

Procedia PDF Downloads 159
2348 Experimental Analysis of Structure Borne Noise in an Enclosure

Authors: Waziralilah N. Fathiah, A. Aminudin, U. Alyaa Hashim, T. Vikneshvaran D. Shakirah Shukor

Abstract:

This paper presents the experimental analysis conducted on a structure borne noise in a rectangular enclosure prototype made by joining of sheet aluminum metal and plywood. The study is significant as many did not realized the annoyance caused by structural borne-noise. In this study, modal analysis is carried out to seek the structure’s behaviour in order to identify the characteristics of enclosure in frequency domain ranging from 0 Hz to 200 Hz. Here, numbers of modes are identified and the characteristic of mode shape is categorized. Modal experiment is used to diagnose the structural behaviour while microphone is used to diagnose the sound. Spectral testing is performed on the enclosure. It is acoustically excited using shaker and as it vibrates, the vibrational and noise responses sensed by tri-axis accelerometer and microphone sensors are recorded respectively. Experimental works is performed on each node lies on the gridded surface of the enclosure. Both experimental measurement is carried out simultaneously. The modal experimental results of the modal modes are validated by simulation performed using MSC Nastran software. In pursuance of reducing the structure borne-noise, mitigation method is used whereby the stiffener plates are perpendicularly placed on the sheet aluminum metal. By using this method, reduction in structure borne-noise is successfully made at the end of the study.

Keywords: enclosure, modal analysis, sound analysis, structure borne-noise

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2347 Problems of Water Resources : Vulnerability to Climate Change, Modeling with Software WEAP 21 (Upper and Middle Cheliff)

Authors: Mehaiguene Madjid, Meddi Mohamed

Abstract:

The results of applying the model WEAP 21 or 'Water Evaluation and Planning System' in Upper and Middle Cheliff are presented in cartographic and graphic forms by considering two scenarios: -Reference scenario 1961-1990, -Climate change scenarios (low and high) for 2020 and 2050. These scenarios are presented together in the results and compared them to know the impact on aquatic systems and water resources. For the low scenario for 2050, a decrease in the rate of runoff / infiltration will be 81.4 to 3.7 Hm3 between 2010 and 2050. While for the high scenario for 2050, the reduction will be 87.2 to 78.9 Hm3 between 2010 and 2050. Comparing the two scenarios, shows that the water supplied will increase by 216.7 Hm3 to 596 Hm3 up to 2050 if we do not take account of climate change. Whereas, if climate change will decrease step by step: from 2010 to 2026: for the climate change scenario (high scenario) by 2050, water supplied from 346 Hm3 to 361 Hm3. That of the reference scenario (1961-1990) will increase to 379.7 Hm3 in 2050. This is caused by the increased demand (increased population, irrigated area, etc ). The balance water management basin is positive for the different Horizons and different situations. If we do not take account of climate change will be the outflow of 5881.4 Hm3. This excess at the basin can be used as part of a transfer for example.

Keywords: balance water, management basin, climate change scenario, Upper and Middle Cheliff

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2346 Thermodynamics of Random Copolymers in Solution

Authors: Maria Bercea, Bernhard A. Wolf

Abstract:

The thermodynamic behavior for solutions of poly (methyl methacrylate-ran-t-butyl methacrylate) of variable composition as compared with the corresponding homopolymers was investigated by light scattering measurements carried out for dilute solutions and vapor pressure measurements of concentrated solutions. The complex dependencies of the Flory Huggins interaction parameter on concentration and copolymer composition in solvents of different polarity (toluene and chloroform) can be understood by taking into account the ability of the polymers to rearrange in a response to changes in their molecular surrounding. A recent unified thermodynamic approach was used for modeling the experimental data, being able to describe the behavior of the different solutions by means of two adjustable parameters, one representing the effective number of solvent segments and another one accounting for the interactions between the components. Thus, it was investigated how the solvent quality changes with the composition of the copolymers through the Gibbs energy of mixing as a function of polymer concentration. The largest reduction of the Gibbs energy at a given composition of the system was observed for the best solvent. The present investigation proves that the new unified thermodynamic approach is a general concept applicable to homo- and copolymers, independent of the chain conformation or shape, molecular and chemical architecture of the components and of other dissimilarities, such as electrical charges.

Keywords: random copolymers, Flory Huggins interaction parameter, Gibbs energy of mixing, chemical architecture

Procedia PDF Downloads 281