Search results for: energy performance certificate EPBD
1567 On-Farm Evaluation of Fast and Slow Growing Genotypes for Organic and Pasture Poultry Production Systems
Authors: Komala Arsi, Terrel Spencer, Casey M. Owens, Dan J. Donoghue, Ann M. Donoghue
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Organic poultry production is becoming increasingly popular in the United States with approximately 17% increase in the sales of organic meat and poultry in 2016. As per the National Organic Program (NOP), organic poultry production system should operate according to specific standards, including access to outdoors. In the United States, organic poultry farmers are raising both fast growing and slow growing genotypes for alternative productive systems. Even though heritage breed birds grow much slower compared to commercial breeds, many free range producers believe that they are better suited for outdoor production systems. We conducted an on-farm trial on a working pasture poultry farm to compare the performance and meat quality characteristics of a slow-growing heritage breed (Freedom Rangers, FR), and two commonly used fast growing types of chickens (Cornish cross, CC and Naked Neck, NN), raised on pasture, in side by side pens segregated by breed (n=70/breed). CC and NN group birds were reared for eight weeks whereas FR group birds were reared for 10 weeks and all the birds were commercially processed. By the end of the rearing period, the final body weight of FR group birds was significantly lower than both the fast growing genotypes (CC and NN). Both CC and NN birds showed significantly higher live weight, carcass weight as well as fillet, tender and leg yield (P < 0.05). There was no difference in the wing and rack yield among the different groups. Color of the meat was measured using CEILAB method and expressed as lightness (L), redness (a*) and yellowness (b*). The breast meat from FR birds was much redder (higher a* values) and less yellow (lesser b* values) compared to both the fast growing type of chickens (P < 0.05). Overall, fast growing genotypes produced higher carcass weight and meat yield compared to slow growing genotypes and appear to be an economical option for alternative production systems.Keywords: fast growing chickens, meat quality, pasture, slow growing chickens
Procedia PDF Downloads 3871566 Modeling of Foundation-Soil Interaction Problem by Using Reduced Soil Shear Modulus
Authors: Yesim Tumsek, Erkan Celebi
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In order to simulate the infinite soil medium for soil-foundation interaction problem, the essential geotechnical parameter on which the foundation stiffness depends, is the value of soil shear modulus. This parameter directly affects the site and structural response of the considered model under earthquake ground motions. Strain-dependent shear modulus under cycling loads makes difficult to estimate the accurate value in computation of foundation stiffness for the successful dynamic soil-structure interaction analysis. The aim of this study is to discuss in detail how to use the appropriate value of soil shear modulus in the computational analyses and to evaluate the effect of the variation in shear modulus with strain on the impedance functions used in the sub-structure method for idealizing the soil-foundation interaction problem. Herein, the impedance functions compose of springs and dashpots to represent the frequency-dependent stiffness and damping characteristics at the soil-foundation interface. Earthquake-induced vibration energy is dissipated into soil by both radiation and hysteretic damping. Therefore, flexible-base system damping, as well as the variability in shear strengths, should be considered in the calculation of impedance functions for achievement a more realistic dynamic soil-foundation interaction model. In this study, it has been written a Matlab code for addressing these purposes. The case-study example chosen for the analysis is considered as a 4-story reinforced concrete building structure located in Istanbul consisting of shear walls and moment resisting frames with a total height of 12m from the basement level. The foundation system composes of two different sized strip footings on clayey soil with different plasticity (Herein, PI=13 and 16). In the first stage of this study, the shear modulus reduction factor was not considered in the MATLAB algorithm. The static stiffness, dynamic stiffness modifiers and embedment correction factors of two rigid rectangular foundations measuring 2m wide by 17m long below the moment frames and 7m wide by 17m long below the shear walls are obtained for translation and rocking vibrational modes. Afterwards, the dynamic impedance functions of those have been calculated for reduced shear modulus through the developed Matlab code. The embedment effect of the foundation is also considered in these analyses. It can easy to see from the analysis results that the strain induced in soil will depend on the extent of the earthquake demand. It is clearly observed that when the strain range increases, the dynamic stiffness of the foundation medium decreases dramatically. The overall response of the structure can be affected considerably because of the degradation in soil stiffness even for a moderate earthquake. Therefore, it is very important to arrive at the corrected dynamic shear modulus for earthquake analysis including soil-structure interaction.Keywords: clay soil, impedance functions, soil-foundation interaction, sub-structure approach, reduced shear modulus
Procedia PDF Downloads 2721565 Environmental Degradation and Sustainable Measures: A Case Study in Nepal
Authors: Megha Raj Regmi
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Water Supply and Sanitation coverage in Nepal is not satisfactory in South Asia. Far less than expected achievements have been realized in sanitation following the SDG for Nepal. There are so many queues of buckets to fetch water in the heart of the capital city Kathmandu. In Kathmandu Valley, daily water demand is 400 million litres, but the supply is only 200 million litres daily. Over- exploitation of ground water and traditional water sources causing the water levels to drop to alarming levels while most of the traditional waterspouts are also drying up. While about 40% of the World's population is deprived of drinking water, the urban populace uses excessive quantities of fresh water to flush the excreta. Water Supply and Basic Sanitation coverage in Nepal is 86% and 92%, respectively, of the total population. This research work basically deals with more than one thousand dry toilets constructed in peri-urban areas. The work has used appropriate technology and studied their performances in the context of Nepal based on complete laboratory analyses and regular monitoring. It has been found that dry toilets have a clear advantage in NPK recovery over traditional water-borne sanitation technology. This paper also deals with the effect of temperature in the decomposition process in dry toilets and also focuses on the different distinct technologies employed in Kathmandu Valley. This paper suggests the modifications needed in the implementation and study of the effect of human urine in composting and application on agriculture and the experience of more than one thousand Dry toilets in Kathmandu Valley. It also deals with the practices of bio-gas generation and community-led total sanitation to cope with the challenges of sanitation and hygiene in Nepal. The paper also describes in depth the different types of biomass energy production methods from the human and cattle manure units, including bio-gas generation from the kitchen wastes produced by a student hostel mixed with toilet waste. The uses of decomposed feces as a soil conditioner have been described along with the challenges and prospects of the uses of urine in agriculture as eco-friendly fertilizer in the context of Nepal. Finally, the paper exhibits a comparative study of all types of dry toilet developments in developed and developing countries like Australia, South Korea, Malaysia, China, India, Ukraine and Nepal. The community groups in our financial assistance have made many models of public toilets with biogas which are very successful in the height of 600 m up to 2000 meters from the mean sea level. In conclusion it makes a plea for the acceptance of these toilets for planners and decision makers with a set of pragmatic recommendations.Keywords: bio- gas public toilet, dry toilet, low-cost technology, sustainable sanitation, total sanitation
Procedia PDF Downloads 141564 Investigation of the Technological Demonstrator 14x B in Different Angle of Attack in Hypersonic Velocity
Authors: Victor Alves Barros Galvão, Israel Da Silveira Rego, Antonio Carlos Oliveira, Paulo Gilberto De Paula Toro
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The Brazilian hypersonic aerospace vehicle 14-X B, VHA 14-X B, is a vehicle integrated with the hypersonic airbreathing propulsion system based on supersonic combustion (scramjet), developing in Aerothermodynamics and hypersonic Prof. Henry T. Nagamatsu Laboratory, to conduct demonstration in atmospheric flight at the speed corresponding to Mach number 7 at an altitude of 30km. In the experimental procedure the hypersonic shock tunnel T3 was used, installed in that laboratory. This device simulates the flow over a model is fixed in the test section and can also simulate different atmospheric conditions. The scramjet technology offers substantial advantages to improve aerospace vehicle performance which flies at a hypersonic speed through the Earth's atmosphere by reducing fuel consumption on board. Basically, the scramjet is an aspirated aircraft engine fully integrated that uses oblique/conic shock waves generated during hypersonic flight, to promote the deceleration and compression of atmospheric air in scramjet inlet. During the hypersonic flight, the vehicle VHA 14-X will suffer atmospheric influences, promoting changes in the vehicle's angles of attack (angle that the mean line of vehicle makes with respect to the direction of the flow). Based on this information, a study is conducted to analyze the influences of changes in the vehicle's angle of attack during the atmospheric flight. Analytical theoretical analysis, simulation computational fluid dynamics and experimental investigation are the methodologies used to design a technological demonstrator prior to the flight in the atmosphere. This paper considers analysis of the thermodynamic properties (pressure, temperature, density, sound velocity) in lower surface of the VHA 14-X B. Also, it considers air as an ideal gas and chemical equilibrium, with and without boundary layer, considering changes in the vehicle's angle of attack (positive and negative in relation to the flow) and bi-dimensional expansion wave theory at the expansion section (Theory of Prandtl-Meyer).Keywords: angle of attack, experimental hypersonic, hypersonic airbreathing propulsion, Scramjet
Procedia PDF Downloads 4101563 Investigation and Comprehensive Benefit Analysis of 11 Typical Polar-Based Agroforestry Models Based on Analytic Hierarchy Process in Anhui Province, Eastern China
Authors: Zhihua Cao, Hongfei Zhao, Zhongneng Wu
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The development of polar-based agroforestry was necessary due to the influence of the timber market environment in China, which can promote the coordinated development of forestry and agriculture, and gain remarkable ecological, economic and social benefits. The main agroforestry models of the main poplar planting area in Huaibei plain and along the Yangtze River plain were carried out. 11 typical management models of poplar were selected to sum up: pure poplar forest, poplar-rape-soybean, poplar-wheat-soybean, poplar-rape-cotton, poplar-wheat, poplar-chicken, poplar-duck, poplar-sheep, poplar-Agaricus blazei, poplar-oil peony, poplar-fish, represented by M0-M10, respectively. 12 indexes related with economic, ecological and social benefits (annual average cost, net income, ratio of output to investment, payback period of investment, land utilization ratio, utilization ratio of light energy, improvement and system stability of ecological and production environment, product richness, labor capacity, cultural quality of labor force, sustainability) were screened out to carry on the comprehensive evaluation and analysis to 11 kinds of typical agroforestry models based on analytic hierarchy process (AHP). The results showed that the economic benefit of each agroforestry model was in the order of: M8 > M6 > M9 > M7 > M5 > M10 > M4 > M1 > M2 > M3 > M0. The economic benefit of poplar-A. blazei model was the highest (332, 800 RMB / hm²), followed by poplar-duck and poplar-oil peony model (109, 820RMB /hm², 5, 7226 RMB /hm²). The order of comprehensive benefit was: M8 > M4 > M9 > M6 > M1 > M2 > M3 > M7 > M5 > M10 > M0. The economic benefit and comprehensive benefit of each agroforestry model were higher than that of pure poplar forest. The comprehensive benefit of poplar-A. blazei model was the highest, and that of poplar-wheat model ranked second, while its economic benefit was not high. Next were poplar-oil peony and poplar-duck models. It was suggested that the model of poplar-wheat should be adopted in the plain along the Yangtze River, and the whole cycle mode of poplar-grain, popalr-A. blazei, or poplar-oil peony should be adopted in Huaibei plain, northern Anhui. Furthermore, wheat, rape, and soybean are the main crops before the stand was closed; the agroforestry model of edible fungus or Chinese herbal medicine can be carried out when the stand was closed in order to maximize the comprehensive benefit. The purpose of this paper is to provide a reference for forest farmers in the selection of poplar agroforestry model in the future and to provide the basic data for the sustainable and efficient study of poplar agroforestry in Anhui province, eastern China.Keywords: agroforestry, analytic hierarchy process (AHP), comprehensive benefit, model, poplar
Procedia PDF Downloads 1661562 Derivation of Fragility Functions of Marine Drilling Risers Under Ocean Environment
Authors: Pranjal Srivastava, Piyali Sengupta
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The performance of marine drilling risers is crucial in the offshore oil and gas industry to ensure safe drilling operation with minimum downtime. Experimental investigations on marine drilling risers are limited in the literature owing to the expensive and exhaustive test setup required to replicate the realistic riser model and ocean environment in the laboratory. Therefore, this study presents an analytical model of marine drilling riser for determining its fragility under ocean environmental loading. In this study, the marine drilling riser is idealized as a continuous beam having a concentric circular cross-section. Hydrodynamic loading acting on the marine drilling riser is determined by Morison’s equations. By considering the equilibrium of forces on the marine drilling riser for the connected and normal drilling conditions, the governing partial differential equations in terms of independent variables z (depth) and t (time) are derived. Subsequently, the Runge Kutta method and Finite Difference Method are employed for solving the partial differential equations arising from the analytical model. The proposed analytical approach is successfully validated with respect to the experimental results from the literature. From the dynamic analysis results of the proposed analytical approach, the critical design parameters peak displacements, upper and lower flex joint rotations and von Mises stresses of marine drilling risers are determined. An extensive parametric study is conducted to explore the effects of top tension, drilling depth, ocean current speed and platform drift on the critical design parameters of the marine drilling riser. Thereafter, incremental dynamic analysis is performed to derive the fragility functions of shallow water and deep-water marine drilling risers under ocean environmental loading. The proposed methodology can also be adopted for downtime estimation of marine drilling risers incorporating the ranges of uncertainties associated with the ocean environment, especially at deep and ultra-deepwater.Keywords: drilling riser, marine, analytical model, fragility
Procedia PDF Downloads 1491561 Impact of Environmental Rule of Law towards Positive Environmental Outcomes in Nigeria
Authors: Kate N. Okeke
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The ever-growing needs of man requiring satisfaction have pushed him strongly towards industrialization which has and is still leaving environmental degradation and its attendant negative impacts in its wake. It is, therefore, not surprising that the enjoyment of fundamental rights like food supply, security of lives and property, freedom of worship, health and education have been drastically affected by such degradation. In recognition of the imperative need to protect the environment and human rights, many global instruments and constitutions have recognized the right to a healthy and sustainable environment. Some environmental advocates and quite a number of literatures on the subject matter call for the recognition of environmental rights via rule of law as a vital means of achieving positive outcomes on the subject matter. However, although there are numerous countries with constitutional environmental provisions, most of them such as Nigeria, have shown poor environmental performance. A notable problem is the fact that the constitution which recognizes environmental rights appears in its other provisions to contradict its provisions by making enforceability of the environmental rights unattainable. While adopting a descriptive, analytical, comparative and explanatory study design in reviewing a successful positive environmental outcome via the rule of law, this article argues that rule of law on a balance of scale, weighs more than just environmental rights recognition and therefore should receive more attention by environmental lawyers and advocates. This is because with rule of law, members of a society are sure of getting the most out of the environmental rights existing in their legal system. Members of Niger-Delta communities of Nigeria will benefit from the environmental rights existing in Nigeria. They are exposed to environmental degradation and pollution with effects such as acidic rainfall, pollution of farmlands and clean water sources. These and many more are consequences of oil and gas exploration. It will also pave way for solving the violence between cattle herdsmen and farmers in the Middle Belt and other regions of Nigeria. Their clashes are over natural resource control. Having seen that environmental rule of law is vital to sustainable development, this paper aims to contribute to discussions on how best the vehicle of rule law can be driven towards achieving positive environmental outcomes. This will be in reliance on other enforceable provisions in the Nigerian Constitution. Other domesticated international instruments will also be considered to attain sustainable environment and development.Keywords: environment, rule of law, constitution, sustainability
Procedia PDF Downloads 1561560 Potential Cross-Protection Roles of Chitooligosaccharide in Alleviating Cd Toxicity in Edible Rape (Brassica rapa L.)
Authors: Haiying Zong, Yi Yuan, Pengcheng Li
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Cadmium (Cd), one of the toxic heavy metals, has high solubility and mobility in agricultural soils and is readily taken up by roots and transported to the vegetative and reproductive organs which can cause deleterious effects on crop yield and quality. Excess Cd in plants can interfere with many metabolic processes, such as photosynthesis, transpiration, respiration or nutrients homeostasis. Generally, the main methods to reduce Cd accumulation in plants are to decrease the concentration of Cd in the soil solution through reduction of Cd influx into the soil system, site selection, and management practices. However, these approaches can be very costly and consume a lot of energy Therefore, it is critical to develop effective approaches to reduce the Cd concentration in plants. It is proved that chitooligosaccharide (COS) can enhance the plant's tolerance to abiotic stress including drought stress, salinity stress, and toxic metal stress. However, so far little information is known about whether foliar application with COS modulates Cd-induced toxicity in plants. The metal detoxification processes of plants treated with COS also remain unclear. In this study, edible rape (Brassica rapa L.), one of the most widely consumed leafy vegetables, was selected as an experimental mode plant. The effect of foliar application with COS on reducing Cd accumulation in edible rape was investigated. Moreover, Cd subcellular distribution pattern in response to Cd stress in the rape plant sprayed with COS was further tested in order to explore the potential detoxification mechanisms in plants. The results demonstrated that spraying COS at different concentrations (25, 50,100 and 200 mg L-1) possess diverse functions including growth-promoting,chlorophyll contents-enhancing, malondialdehyde (MDA) level-decreasing in leaves, Cd2+ concentration-decreasingin shoots and roots of edible rape under Cd stress. In addition, it was found that COS can also dramatically improve superoxide dismutase (SOD) activity, catalase (CAT) activity and peroxidase (POX) activity of edible rape leaves. The relievingeffect of COS was related to theconcentration and COS with 50-100 mg L-1 displayed the best activity. Furtherly, theexperiments results exhibitedthat COS could decrease the proportion of Cd in the organelle fraction of leaves by 40.1% while enhance the proportion of Cd in the soluble fraction by 13.2% at the concentration of 50 mg L-1. The above results showed that COS may have thepotential to improve plant resistance to Cd via promoting antioxidant enzyme activities and altering Cd subcellular distribution. All the results described here open up a new way to study the protection role of COS in alleviating Cd tolerance and lay the foundation for future research about the detoxification mechanism at subcellular level.Keywords: chitooligosaccharide, cadmium, edible rape (Brassica rapa L.), subcellular distribution
Procedia PDF Downloads 2951559 Benefits of Shaping a Balance on Environmental and Economic Sustainability for Population Health
Authors: Edna Negron-Martinez
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Our time's global challenges and trends —like those associated with climate change, demographics displacements, growing health inequalities, and increasing burden of diseases— have complex connections to the determinants of health. Information on the burden of disease causes and prevention is fundamental for public health actions, like preparedness and responses for disasters, and recovery resources after the event. For instance, there is an increasing consensus about key findings of the effects and connections of the global burden of disease, as it generates substantial healthcare costs, consumes essential resources and prevents the attainment of optimal health and well-being. The goal of this research endeavor is to promote a comprehensive understanding of the connections between social, environmental, and economic influences on health. These connections are illustrated by pulling from clearly the core curriculum of multidisciplinary areas —as urban design, energy, housing, and economy— as well as in the health system itself. A systematic review of primary and secondary data included a variety of issues as global health, natural disasters, and critical pollution impacts on people's health and the ecosystems. Environmental health is challenged by the unsustainable consumption patterns and the resulting contaminants that abound in many cities and urban settings around the world. Poverty, inadequate housing, and poor health are usually linked. The house is a primary environmental health context for any individual and especially for more vulnerable groups; such as children, older adults and those who are sick. Nevertheless, very few countries show strong decoupling of environmental degradation from economic growth, as indicated by a recent 2017 Report of the World Bank. Worth noting, the environmental fraction of the global burden of disease in a 2016 World Health Organization (WHO) report estimated that 12.6 million global deaths, accounting for 23% (95% CI: 13-34%) of all deaths were attributable to the environment. Among the environmental contaminants include heavy metals, noise pollution, light pollution, and urban sprawl. Those key findings make a call to the significance to urgently adopt in a global scale the United Nations post-2015 Sustainable Development Goals (SDGs). The SDGs address the social, environmental, and economic factors that influence health and health inequalities, advising how these sectors, in turn, benefit from a healthy population. Consequently, more actions are necessary from an inter-sectoral and systemic paradigm to enforce an integrated sustainability policy implementation aimed at the environmental, social, and economic determinants of health.Keywords: building capacity for workforce development, ecological and environmental health effects of pollution, public health education, sustainability
Procedia PDF Downloads 1091558 Evaluation of Suspended Particles Impact on Condensation in Expanding Flow with Aerodynamics Waves
Authors: Piotr Wisniewski, Sławomir Dykas
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Condensation has a negative impact on turbomachinery efficiency in many energy processes.In technical applications, it is often impossible to dry the working fluid at the nozzle inlet. One of the most popular working fluid is atmospheric air that always contains water in form of steam, liquid, or ice crystals. Moreover, it always contains some amount of suspended particles which influence the phase change process. It is known that the phenomena of evaporation or condensation are connected with release or absorption of latent heat, what influence the fluid physical properties and might affect the machinery efficiency therefore, the phase transition has to be taken under account. This researchpresents an attempt to evaluate the impact of solid and liquid particles suspended in the air on the expansion of moist air in a low expansion rate, i.e., with expansion rate, P≈1000s⁻¹. The numerical study supported by analytical and experimental research is presented in this work. The experimental study was carried out using an in-house experimental test rig, where nozzle was examined for different inlet air relative humidity values included in the range of 25 to 51%. The nozzle was tested for a supersonic flow as well as for flow with shock waves induced by elevated back pressure. The Schlieren photography technique and measurement of static pressure on the nozzle wall were used for qualitative identification of both condensation and shock waves. A numerical model validated against experimental data available in the literature was used for analysis of occurring flow phenomena. The analysis of the suspended particles number, diameter, and character (solid or liquid) revealed their connection with heterogeneous condensation importance. If the expansion of fluid without suspended particlesis considered, the condensation triggers so called condensation wave that appears downstream the nozzle throat. If the solid particles are considered, with increasing number of them, the condensation triggers upwind the nozzle throat, decreasing the condensation wave strength. Due to the release of latent heat during condensation, the fluid temperature and pressure increase, leading to the shift of normal shock upstream the flow. Owing relatively large diameters of the droplets created during heterogeneous condensation, they evaporate partially on the shock and continues to evaporate downstream the nozzle. If the liquid water particles are considered, due to their larger radius, their do not affect the expanding flow significantly, however might be in major importance while considering the compression phenomena as they will tend to evaporate on the shock wave. This research proves the need of further study of phase change phenomena in supersonic flow especially considering the interaction of droplets with the aerodynamic waves in the flow.Keywords: aerodynamics, computational fluid dynamics, condensation, moist air, multi-phase flows
Procedia PDF Downloads 1191557 The Direct Deconvolutional Model in the Large-Eddy Simulation of Turbulence
Authors: Ning Chang, Zelong Yuan, Yunpeng Wang, Jianchun Wang
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The utilization of Large Eddy Simulation (LES) has been extensive in turbulence research. LES concentrates on resolving the significant grid-scale motions while representing smaller scales through subfilter-scale (SFS) models. The deconvolution model, among the available SFS models, has proven successful in LES of engineering and geophysical flows. Nevertheless, the thorough investigation of how sub-filter scale dynamics and filter anisotropy affect SFS modeling accuracy remains lacking. The outcomes of LES are significantly influenced by filter selection and grid anisotropy, factors that have not been adequately addressed in earlier studies. This study examines two crucial aspects of LES: Firstly, the accuracy of direct deconvolution models (DDM) is evaluated concerning sub-filter scale (SFS) dynamics across varying filter-to-grid ratios (FGR) in isotropic turbulence. Various invertible filters are employed, including Gaussian, Helmholtz I and II, Butterworth, Chebyshev I and II, Cauchy, Pao, and rapidly decaying filters. The importance of FGR becomes evident as it plays a critical role in controlling errors for precise SFS stress prediction. When FGR is set to 1, the DDM models struggle to faithfully reconstruct SFS stress due to inadequate resolution of SFS dynamics. Notably, prediction accuracy improves when FGR is set to 2, leading to accurate reconstruction of SFS stress, except for cases involving Helmholtz I and II filters. Remarkably high precision, nearly 100%, is achieved at an FGR of 4 for all DDM models. Furthermore, the study extends to filter anisotropy and its impact on SFS dynamics and LES accuracy. By utilizing the dynamic Smagorinsky model (DSM), dynamic mixed model (DMM), and direct deconvolution model (DDM) with anisotropic filters, aspect ratios (AR) ranging from 1 to 16 are examined in LES filters. The results emphasize the DDM’s proficiency in accurately predicting SFS stresses under highly anisotropic filtering conditions. Notably high correlation coefficients exceeding 90% are observed in the a priori study for the DDM’s reconstructed SFS stresses, surpassing those of the DSM and DMM models. However, these correlations tend to decrease as filter anisotropy increases. In the a posteriori analysis, the DDM model consistently outperforms the DSM and DMM models across various turbulence statistics, including velocity spectra, probability density functions related to vorticity, SFS energy flux, velocity increments, strainrate tensors, and SFS stress. It is evident that as filter anisotropy intensifies, the results of DSM and DMM deteriorate, while the DDM consistently delivers satisfactory outcomes across all filter-anisotropy scenarios. These findings underscore the potential of the DDM framework as a valuable tool for advancing the development of sophisticated SFS models for LES in turbulence research.Keywords: deconvolution model, large eddy simulation, subfilter scale modeling, turbulence
Procedia PDF Downloads 761556 Application of Multilayer Perceptron and Markov Chain Analysis Based Hybrid-Approach for Predicting and Monitoring the Pattern of LULC Using Random Forest Classification in Jhelum District, Punjab, Pakistan
Authors: Basit Aftab, Zhichao Wang, Feng Zhongke
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Land Use and Land Cover Change (LULCC) is a critical environmental issue that has significant effects on biodiversity, ecosystem services, and climate change. This study examines the spatiotemporal dynamics of land use and land cover (LULC) across a three-decade period (1992–2022) in a district area. The goal is to support sustainable land management and urban planning by utilizing the combination of remote sensing, GIS data, and observations from Landsat satellites 5 and 8 to provide precise predictions of the trajectory of urban sprawl. In order to forecast the LULCC patterns, this study suggests a hybrid strategy that combines the Random Forest method with Multilayer Perceptron (MLP) and Markov Chain analysis. To predict the dynamics of LULC change for the year 2035, a hybrid technique based on multilayer Perceptron and Markov Chain Model Analysis (MLP-MCA) was employed. The area of developed land has increased significantly, while the amount of bare land, vegetation, and forest cover have all decreased. This is because the principal land types have changed due to population growth and economic expansion. The study also discovered that between 1998 and 2023, the built-up area increased by 468 km² as a result of the replacement of natural resources. It is estimated that 25.04% of the study area's urbanization will be increased by 2035. The performance of the model was confirmed with an overall accuracy of 90% and a kappa coefficient of around 0.89. It is important to use advanced predictive models to guide sustainable urban development strategies. It provides valuable insights for policymakers, land managers, and researchers to support sustainable land use planning, conservation efforts, and climate change mitigation strategies.Keywords: land use land cover, Markov chain model, multi-layer perceptron, random forest, sustainable land, remote sensing.
Procedia PDF Downloads 351555 Statistical Characteristics of Code Formula for Design of Concrete Structures
Authors: Inyeol Paik, Ah-Ryang Kim
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In this research, a statistical analysis is carried out to examine the statistical properties of the formula given in the design code for concrete structures. The design formulas of the Korea highway bridge design code - the limit state design method (KHBDC) which is the current national bridge design code and the design code for concrete structures by Korea Concrete Institute (KCI) are applied for the analysis. The safety levels provided by the strength formulas of the design codes are defined based on the probabilistic and statistical theory.KHBDC is a reliability-based design code. The load and resistance factors of this code were calibrated to attain the target reliability index. It is essential to define the statistical properties for the design formulas in this calibration process. In general, the statistical characteristics of a member strength are due to the following three factors. The first is due to the difference between the material strength of the actual construction and that used in the design calculation. The second is the difference between the actual dimensions of the constructed sections and those used in design calculation. The third is the difference between the strength of the actual member and the formula simplified for the design calculation. In this paper, the statistical study is focused on the third difference. The formulas for calculating the shear strength of concrete members are presented in different ways in KHBDC and KCI. In this study, the statistical properties of design formulas were obtained through comparison with the database which comprises the experimental results from the reference publications. The test specimen was either reinforced with the shear stirrup or not. For an applied database, the bias factor was about 1.12 and the coefficient of variation was about 0.18. By applying the statistical properties of the design formula to the reliability analysis, it is shown that the resistance factors of the current design codes satisfy the target reliability indexes of both codes. Also, the minimum resistance factors of the KHBDC which is written in the material resistance factor format and KCE which is in the member resistance format are obtained and the results are presented. A further research is underway to calibrate the resistance factors of the high strength and high-performance concrete design guide.Keywords: concrete design code, reliability analysis, resistance factor, shear strength, statistical property
Procedia PDF Downloads 3211554 Importance of Detecting Malingering Patients in Clinical Setting
Authors: Sakshi Chopra, Harsimarpreet Kaur, Ashima Nehra
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Objectives: Malingering is fabricating or exaggerating the symptoms of mental or physical disorders for a variety of secondary gains or motives, which may include financial compensation; avoiding work; getting lighter criminal sentences; or simply to attract attention or sympathy. Malingering is different from somatization disorder and factitious disorder. The prevalence of malingering is unknown and difficult to determine. In an estimated study in forensic population, it can reach up to 17% cases. But the accuracy of such estimates is questionable as successful malingerers are not detected and thus, not included. Methods: The case study of a 58 years old, right handed, graduate, pre-morbidly working in a national company with reported history of stroke leading to head injury; cerebral infarction/facial palsy and dementia. He was referred for disability certification so that his job position can be transferred to his son as he could not work anymore. A series of Neuropsychological tests were administered. Results: With a mental age of < 2.5 years; social adaptive functioning was overall < 20 showing profound Mental Retardation, less than 1 year social age in abilities of self-help, eating, dressing, locomotion, occupation, communication, self-direction, and socialization; severely impaired verbal and performance ability, 96% impairment in Activities of Daily Living, with an indication of very severe depression. With inconsistent and fluctuating medical findings and problem descriptions to different health professionals forming the board for his disability, it was concluded that this patient was malingering. Conclusions: Even though it can be easily defined, malingering can be very challenging to diagnosis. Cases of malingering impose a substantial economic burden on the health care system and false attribution of malingering imposes a substantial burden of suffering on a significant proportion of the patient population. Timely, tactful diagnosis and management can help ease this patient burden on the healthcare system. Malingering can be detected by only trained mental health professionals in the clinical setting.Keywords: disability, India, malingering, neuropsychological assessment
Procedia PDF Downloads 4201553 Results and Insights from a Developmental Psychology Study on the Presentation of Juvenility in Punk Fanzines
Authors: Marc Dietrich
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Youth cultures like Punk as much as media relevant to the specific scenes associated with them offer ample opportunity for young people or juvenile adults to construct their personal identities. However, developmental psychology has largely neglected such identity construction processes during the last decades. Such was not always the case: Early developmental psychologists intensely studied youth cultures and their meaningful objects and media in the early 20th century but lost interest when cultural studies and the social sciences occupied the field after World War II. Our project Constructions of Juvenility and Generation(ality), funded by the German Federal Ministry for Education and Research, reintegrates the study of youth cultures and their meaningful objects and media in a developmental psychology perspective. We present an empirical study of the ways in which youth, juvenility, and generation (ality) are constructed and negotiated in underground media like punk fanzines (a portmanteau of fan and magazine), including both semantic and aesthetic aspects of these construction processes within punk culture. The fanzine sample was accessed by the theoretical sampling strategy typical for GTM studies. Acknowledging fanzines as artful self-produced media by scene members for scene members, we conceptualize them as authentic documents of scene norms and values. Drawing on an analysis of both text and (cover) images in Punk fanzines published in Germany (and within a sample dating from 1981 until 2015) using a novel Visual Grounded Theory approach, we found that: a) Juvenility is a highly contested concept in punk culture. Its semantic quality and valuation varies with the perspectives present within the culture (e.g. embryo punks versus older punks); b) Juvenility is constructed as having energy and being socio-critical that does not depend on biological age; c) Juvenility is regarded not an ideal per se in German Punk culture; Punk culture constructs old age in a largely positive way (e.g., as marker of being real and a historical innovator); d) Juvenility is constructed as a habit that should be kept for life as it is constantly adapted to individual biographical trajectories like specific job situations or having a family. Consequently, identity negotiation as documented in the zines attempts to balance subculturally driven perspectives on life and society with the pragmatic requirements of a bourgeois life. The proposed paper will present the main results of this large-scale study of punk fanzines and show how developmental psychology perspectives as represented in the novel methodology applied in it can advance the study of youth cultures.Keywords: construction of juvenility, developmental psychology, visual GTM, youth culture, fanzines
Procedia PDF Downloads 2941552 Modification of Magneto-Transport Properties of Ferrimagnetic Mn₄N Thin Films by Ni Substitution and Their Magnetic Compensation
Authors: Taro Komori, Toshiki Gushi, Akihito Anzai, Taku Hirose, Kaoru Toko, Shinji Isogami, Takashi Suemasu
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Ferrimagnetic antiperovskite Mn₄₋ₓNiₓN thin film exhibits both small saturation magnetization and rather large perpendicular magnetic anisotropy (PMA) when x is small. Both of them are suitable features for application to current induced domain wall motion devices using spin transfer torque (STT). In this work, we successfully grew antiperovskite 30-nm-thick Mn₄₋ₓNiₓN epitaxial thin films on MgO(001) and STO(001) substrates by MBE in order to investigate their crystalline qualities and magnetic and magneto-transport properties. Crystalline qualities were investigated by X-ray diffraction (XRD). The magnetic properties were measured by vibrating sample magnetometer (VSM) at room temperature. Anomalous Hall effect was measured by physical properties measurement system. Both measurements were performed at room temperature. Temperature dependence of magnetization was measured by VSM-Superconducting quantum interference device. XRD patterns indicate epitaxial growth of Mn₄₋ₓNiₓN thin films on both substrates, ones on STO(001) especially have higher c-axis orientation thanks to greater lattice matching. According to VSM measurement, PMA was observed in Mn₄₋ₓNiₓN on MgO(001) when x ≤ 0.25 and on STO(001) when x ≤ 0.5, and MS decreased drastically with x. For example, MS of Mn₃.₉Ni₀.₁N on STO(001) was 47.4 emu/cm³. From the anomalous Hall resistivity (ρAH) of Mn₄₋ₓNiₓN thin films on STO(001) with the magnetic field perpendicular to the plane, we found out Mr/MS was about 1 when x ≤ 0.25, which suggests large magnetic domains in samples and suitable features for DW motion device application. In contrast, such square curves were not observed for Mn₄₋ₓNiₓN on MgO(001), which we attribute to difference in lattice matching. Furthermore, it’s notable that although the sign of ρAH was negative when x = 0 and 0.1, it reversed positive when x = 0.25 and 0.5. The similar reversal occurred for temperature dependence of magnetization. The magnetization of Mn₄₋ₓNiₓN on STO(001) increases with decreasing temperature when x = 0 and 0.1, while it decreases when x = 0.25. We considered that these reversals were caused by magnetic compensation which occurred in Mn₄₋ₓNiₓN between x = 0.1 and 0.25. We expect Mn atoms of Mn₄₋ₓNiₓN crystal have larger magnetic moments than Ni atoms do. The temperature dependence stated above can be explained if we assume that Ni atoms preferentially occupy the corner sites, and their magnetic moments have different temperature dependence from Mn atoms at the face-centered sites. At the compensation point, Mn₄₋ₓNiₓN is expected to show very efficient STT and ultrafast DW motion with small current density. What’s more, if angular momentum compensation is found, the efficiency will be best optimized. In order to prove the magnetic compensation, X-ray magnetic circular dichroism will be performed. Energy dispersive X-ray spectrometry is a candidate method to analyze the accurate composition ratio of samples.Keywords: compensation, ferrimagnetism, Mn₄N, PMA
Procedia PDF Downloads 1351551 Syntheses of Anionic Poly(urethanes) with Imidazolium, Phosphonium, and Ammonium as Counter-cations and Their Evaluation for CO2 Separation
Authors: Franciele L. Bernard, Felipe Dalla Vecchia, Barbara B. Polesso, Jose A. Donato, Marcus Seferin, Rosane Ligabue, Jailton F. do Nascimento, Sandra Einloft
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The increasing level of carbon dioxide concentration in the atmosphere related to fossil fuels processing and utilization are contributing to global warming phenomena considerably. Carbon capture and storage (CCS) technologies appear as one of the key technologies to reduce CO2 emissions mitigating the effects of climate change. Absorption using amines solutions as solvents have been extensively studied and used in industry for decades. However, solvent degradation and equipment corrosion are two of the main problems in this process. Poly (ionic liquid) (PIL) is considered as a promising material for CCS technology, potentially more environmentally friendly and lesser energy demanding than traditional material. PILs possess a unique combination of ionic liquids (ILs) features, such as affinity for CO2, thermal and chemical stability and adjustable properties, coupled with the intrinsic properties of the polymer. This study investigated new Poly (ionic liquid) (PIL) based on polyurethanes with different ionic liquids cations and its potential for CO2 capture. The PILs were synthesized by the addition of diisocyante to a difunctional polyol, followed by an exchange reaction with the ionic Liquids 1-butyl-3-methylimidazolium chloride (BMIM Cl); tetrabutylammonium bromide (TBAB) and tetrabutylphosphonium bromide (TBPB). These materials were characterized by Fourier transform infrared spectroscopy (FTIR), Proton Nuclear Magnetic Resonance (1H-NMR), Atomic force microscopy (AFM), Tensile strength analysis, Field emission scanning electron microscopy (FESEM), Thermogravimetric analysis (TGA), Differential scanning calorimetry (DSC). The PILs CO2 sorption capacity were gravimetrically assessed in a Magnetic Suspension Balance (MSB). It was found that the ionic liquids cation influences in the compounds properties as well as in the CO2 sorption. The best result for CO2 sorption (123 mgCO2/g at 30 bar) was obtained for the PIL (PUPT-TBA). The higher CO2 sorption in PUPT-TBA is probably linked to the fact that the tetraalkylammonium cation having a higher positive density charge can have a stronger interaction with CO2, while the imidazolium charge is delocalized. The comparative CO2 sorption values of the PUPT-TBA with different ionic liquids showed that this material has greater capacity for capturing CO2 when compared to the ILs even at higher temperature. This behavior highlights the importance of this study, as the poly (urethane) based PILs are cheap and versatile materials.Keywords: capture, CO2, ionic liquids, ionic poly(urethane)
Procedia PDF Downloads 2351550 Phase Optimized Ternary Alloy Material for Gas Turbines
Authors: Mayandi Ramanathan
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Gas turbine blades see the most aggressive thermal stress conditions within the engine, due to Turbine Entry Temperatures in the range of 1500 to 1600°C, but in synchronization with other functional components, they must readily deliver efficient performance, whilst incurring minimal overhaul and repair costs during its service life up to 5 million flying miles. The blades rotate at very high rotation rates and remove significant amount of thermal power from the gas stream. At high temperatures the major component failure mechanism is creep. During its service over time under high temperatures and loads, the blade will deform, lengthen and rupture. High strength and stiffness in the longitudinal direction up to elevated service temperatures are certainly the most needed properties of turbine blades. The proposed advanced Ti alloy material needs a process that provides strategic orientation of metallic ordering, uniformity in composition and high metallic strength. 25% Ta/(Al+Ta) ratio ensures TaAl3 phase formation, where as 51% Al/(Al+Ti) ratio ensures formation of α-Ti3Al and γ-TiAl mixed phases fand the three phase combination ensures minimal Al excess (~1.4% Al excess), unlike Ti-47Al-2Cr-2Nb which has significant excess Al (~5% Al excess) that could affect the service life of turbine blades. This presentation will involve the summary of additive manufacturing and heat treatment process conditions to fabricate turbine blade with Ti-43Al matrix alloyed with optimized amount of refractory Ta metal. Summary of thermo-mechanical test results such as high temperature tensile strength, creep strain rate, thermal expansion coefficient and fracture toughness will be presented. Improvement in service temperature of the turbine blades and corrosion resistance dependence on coercivity of the alloy material will be reported. Phase compositions will be quantified, and a summary of its correlation with creep strain rate will be presented.Keywords: gas turbine, aerospace, specific strength, creep, high temperature materials, alloys, phase optimization
Procedia PDF Downloads 1811549 Water Management of Polish Agriculture and Adaptation to Climate Change
Authors: Dorota M. Michalak
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The agricultural sector, due to the growing demand for food and over-exploitation of the natural environment, contributes to the deepening of climate change, on the one hand, and on the other hand, shrinking freshwater resources, as a negative effect of climate change, threaten the food security of each country. Therefore, adaptation measures to climate change should take into account effective water management and seek solutions ensuring food production at an unchanged or higher level, while not burdening the environment and not contributing to the worsening of the negative consequences of climate change. The problems of Poland's water management result not only from relatively small, natural water resources but to a large extent on the low efficiency of their use. Appropriate agricultural practices and state solutions in this field can contribute to achieving significant benefits in terms of economical water management in agriculture, providing a greater amount of water that could also be used for other purposes, including for purposes related to environmental protection. The aim of the article is to determine the level of use of water resources in Polish agriculture and the advancement of measures aimed at adapting Polish agriculture in the field of water management to climate change. The study provides knowledge about Polish legal regulations and water management tools, the shaping of water policy of Polish agriculture against the background of EU countries and other sources of energy, and measures supporting Polish agricultural holdings in the effective management of water resources run by state budget institutions. In order to achieve the above-mentioned goals, the author used research tools such as the analysis of existing sources and a survey conducted among five groups of entities, i.e. agricultural advisory centers and departments, agricultural, rural and environmental protection departments, regional water management boards, provincial agricultural chambers and restructuring and modernization of agriculture. The main conclusion of the analyses carried out is the low use of water in Polish agriculture in relation to other EU countries, other sources of intake in Poland, as well as irrigation. The analysis allows us to observe another problem, which is the lack of reporting and data collection, which is extremely important from the point of view of the effectiveness of adaptation measures to climate change. The results obtained from the survey indicate a very low level of support for government institutions in the implementation of adaptation measures to climate change and the water management of Polish farms. Some of the basic problems of the adaptation policy to change climate with regard to water management in Polish agriculture include a lack of knowledge regarding climate change, the possibilities of adapting, the available tools or ways to rationalize the use of water resources. It also refers to the lack of ordering procedures and the separation of responsibility with a proper territorial unit, non-functioning channels of information flow and practically low effects.Keywords: water management, adaptation policy, agriculture, climate change
Procedia PDF Downloads 1421548 Remediation of Dye Contaminated Wastewater Using N, Pd Co-Doped TiO₂ Photocatalyst Derived from Polyamidoamine Dendrimer G1 as Template
Authors: Sarre Nzaba, Bulelwa Ntsendwana, Bekkie Mamba, Alex Kuvarega
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The discharge of azo dyes such as Brilliant black (BB) into the water bodies has carcinogenic and mutagenic effects on humankind and the ecosystem. Conventional water treatment techniques fail to degrade these dyes completely thereby posing more problems. Advanced oxidation processes (AOPs) are promising technologies in solving the problem. Anatase type nitrogen-platinum (N, Pt) co-doped TiO₂ photocatalysts were prepared by a modified sol-gel method using amine terminated polyamidoamine generation 1 (PG1) as a template and source of nitrogen. The resultant photocatalysts were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X‐ray photoelectron spectroscopy (XPS), UV‐Vis diffuse reflectance spectroscopy, photoluminescence spectroscopy (PL), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy (RS), thermal gravimetric analysis (TGA). The results showed that the calcination atmosphere played an important role in the morphology, crystal structure, spectral absorption, oxygen vacancy concentration, and visible light photocatalytic performance of the catalysts. Anatase phase particles ranging between 9- 20 nm were also confirmed by TEM, SEM, and analysis. The origin of the visible light photocatalytic activity was attributed to both the elemental N and Pd dopants and the existence of oxygen vacancies. Co-doping imparted a shift in the visible region of the solar spectrum. The visible light photocatalytic activity of the samples was investigated by monitoring the photocatalytic degradation of brilliant black dye. Co-doped TiO₂ showed greater photocatalytic brilliant black degradation efficiency compared to singly doped N-TiO₂ or Pd-TiO₂ under visible light irradiation. The highest reaction rate constant of 3.132 x 10-2 min⁻¹ was observed for N, Pd co-doped TiO₂ (2% Pd). The results demonstrated that the N, Pd co-doped TiO₂ (2% Pd) sample could completely degrade the dye in 3 h, while the commercial TiO₂ showed the lowest dye degradation efficiency (52.66%).Keywords: brilliant black, Co-doped TiO₂, polyamidoamine generation 1 (PAMAM G1), photodegradation
Procedia PDF Downloads 1791547 Chemical Technology Approach for Obtaining Carbon Structures Containing Reinforced Ceramic Materials Based on Alumina
Authors: T. Kuchukhidze, N. Jalagonia, T. Archuadze, G. Bokuchava
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The growing scientific-technological progress in modern civilization causes actuality of producing construction materials which can successfully work in conditions of high temperature, radiation, pressure, speed, and chemically aggressive environment. Such extreme conditions can withstand very few types of materials and among them, ceramic materials are in the first place. Corundum ceramics is the most useful material for creation of constructive nodes and products of various purposes for its low cost, easy accessibility to raw materials and good combination of physical-chemical properties. However, ceramic composite materials have one disadvantage; they are less plastics and have lower toughness. In order to increase the plasticity, the ceramics are reinforced by various dopants, that reduces the growth of the cracks. It is shown, that adding of even small amount of carbon fibers and carbon nanotubes (CNT) as reinforcing material significantly improves mechanical properties of the products, keeping at the same time advantages of alundum ceramics. Graphene in composite material acts in the same way as inorganic dopants (MgO, ZrO2, SiC and others) and performs the role of aluminum oxide inhibitor, as it creates shell, that gives possibility to reduce sintering temperature and at the same time it acts as damper, because scattering of a shock wave takes place on carbon structures. Application of different structural modification of carbon (graphene, nanotube and others) as reinforced material, gives possibility to create multi-purpose highly requested composite materials based on alundum ceramics. In the present work offers simplified technology for obtaining of aluminum oxide ceramics, reinforced with carbon nanostructures, during which chemical modification with doping carbon nanostructures will be implemented in the process of synthesis of final powdery composite – Alumina. In charge doping carbon nanostructures connected to matrix substance with C-O-Al bonds, that provide their homogeneous spatial distribution. In ceramic obtained as a result of consolidation of such powders carbon fragments equally distributed in the entire matrix of aluminum oxide, that cause increase of bending strength and crack-resistance. The proposed way to prepare the charge simplifies the technological process, decreases energy consumption, synthesis duration and therefore requires less financial expenses. In the implementation of this work, modern instrumental methods were used: electronic and optical microscopy, X-ray structural and granulometric analysis, UV, IR, and Raman spectroscopy.Keywords: ceramic materials, α-Al₂O₃, carbon nanostructures, composites, characterization, hot-pressing
Procedia PDF Downloads 1211546 Cultural Orientation as a Moderator between Social Support Needs and Psychological Well-Being among Canadian University Students
Authors: Allison Streutker, Josephine Tan
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Universities across Canada have experienced unprecedented growth in international student enrollment from across the world. As cultural diversity in Canada and other countries increases, understanding the social support needs of all students is important for providing them with the assistance they need to thrive psychologically and academically. Those from individualistic cultural orientations tend to seek explicit social support, which involves expressly asking for assistance in times of stress. However, those from collectivistic cultural orientations are more likely to seek implicit social support, where encouragement is obtained from spending time among valued social groups without explicitly talking about problems. This study explored whether the relationship between the type of social support needs (implicit or explicit) and psychological and academic functioning might be moderated by cultural orientations (individualistic, collectivistic) among university students. Participants were 110 university students (70 women, 40 men; mean age = 24.8 years, SD = 6.6). They completed the Individualism and Collectivism Scale (ICS), Perceived Stress Scale (PSS), Interpersonal Support Evaluation List (ISEL) which assesses implicit and explicit social support, Satisfaction with Life Scale (SWLS), Scale of Positive and Negative Experience (SPANE) which yields positive and negative experience scores, Flourishing Scale (FS), and reported their grade point average (GPA) as a measure of academic performance. Moderated regression analysis demonstrated that, for those scoring lower on individualism, reporting lower level of implicit support predicted higher levels of perceived stress. For those scoring higher on individualism, lower levels of explicit social support predicted higher levels of perceived stress and a greater number of negative experiences. Generally, higher levels of implicit support were associated with greater satisfaction with life for all students, with the association becoming stronger among students with higher collectivism scores. No other significant findings were found. The results point to the value of considering the cultural orientations of students when designing programs to maintain and improve their sense of well-being.Keywords: cultural orientation, social support, university students, well-being
Procedia PDF Downloads 2371545 Processing and Characterization of Oxide Dispersion Strengthened (ODS) Fe-14Cr-3W-0.5Ti-0.3Y₂O₃ (14YWT) Ferritic Steel
Authors: Farha Mizana Shamsudin, Shahidan Radiman, Yusof Abdullah, Nasri Abdul Hamid
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Oxide dispersion strengthened (ODS) ferritic steels are amongst the most promising candidates for large scale structural materials to be applied in next generation fission and fusion nuclear power reactors. This kind of material is relatively stable at high temperature, possess remarkable mechanical properties and comparatively good resistance from neutron radiation damage. The superior performance of ODS ferritic steels over their conventional properties is attributed to the high number density of nano-sized dispersoids that act as nucleation sites and stable sinks for many small helium bubbles resulting from irradiation, and also as pinning points to dislocation movement and grain growth. ODS ferritic steels are usually produced by powder metallurgical routes involving mechanical alloying (MA) process of Y2O3 and pre-alloyed or elemental metallic powders, and then consolidated by hot isostatic pressing (HIP) or hot extrusion (HE) techniques. In this study, Fe-14Cr-3W-0.5Ti-0.3Y₂O₃ (designated as 14YWT) was produced by mechanical alloying process and followed by hot isostatic pressing (HIP) technique. Crystal structure and morphology of this sample were identified and characterized by using X-ray Diffraction (XRD) and field emission scanning electron microscope (FESEM) respectively. The magnetic measurement of this sample at room temperature was carried out by using a vibrating sample magnetometer (VSM). FESEM micrograph revealed a homogeneous microstructure constituted by fine grains of less than 650 nm in size. The ultra-fine dispersoids of size between 5 nm to 19 nm were observed homogeneously distributed within the BCC matrix. The EDS mapping reveals that the dispersoids contain Y-Ti-O nanoclusters and from the magnetization curve plotted by VSM, this sample approaches the behavior of soft ferromagnetic materials. In conclusion, ODS Fe-14Cr-3W-0.5Ti-0.3Y₂O₃ (14YWT) ferritic steel was successfully produced by HIP technique in this present study.Keywords: hot isostatic pressing, magnetization, microstructure, ODS ferritic steel
Procedia PDF Downloads 3201544 Eco-Design of Construction Industrial Park in China with Selection of Candidate Tenants
Authors: Yang Zhou, Kaijian Li, Guiwen Liu
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Offsite construction is an innovative alternative to conventional site-based construction, with wide-ranging benefits. It requires building components, elements or modules were prefabricated and pre-assembly before installed into their final locations. To improve efficiency and achieve synergies, in recent years, construction companies were clustered into construction industrial parks (CIPs) in China. A CIP is a community of construction manufacturing and service businesses located together on a common property. Companies involved in industrial clusters can obtain environment and economic benefits by sharing resources and information in a given region. Therefore, the concept of industrial symbiosis (IS) can be applied to the traditional CIP to achieve sustainable industrial development or redevelopment through the implementation of eco-industrial parks (EIP). However, before designing a symbiosis network between companies in a CIP, candidate support tenants need to be selected to complement the existing construction companies. In this study, an access indicator system and a linear programming model are established to select candidate tenants in a CIP while satisfying the degree of connectivity among the enterprises in the CIP, minimizing the environmental impact, and maximizing the annualized profit of the CIP. The access indicator system comprises three primary indicators and fifteen secondary indicators, is proposed from the perspective of park-based level. The fifteen indicators are classified as three primary indicators including industrial symbiosis, environment performance and economic benefit, according to the three dimensions of sustainability (environment, economic and social dimensions) and the three R's of the environment (reduce, reuse and recycle). The linear programming model is a method to assess the satisfactoriness of all the indicators and to make an optimal multi-objective selection among candidate tenants. This method provides a practical tool for planners of a CIP in evaluating which among the candidate tenants would best complement existing anchor construction tenants. The reasonability and validity of the indicator system and the method is worth further study in the future.Keywords: construction industrial park, China, industrial symbiosis, offsite construction, selection of support tenants
Procedia PDF Downloads 2751543 CO₂ Recovery from Biogas and Successful Upgrading to Food-Grade Quality: A Case Study
Authors: Elisa Esposito, Johannes C. Jansen, Loredana Dellamuzia, Ugo Moretti, Lidietta Giorno
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The reduction of CO₂ emission into the atmosphere as a result of human activity is one of the most important environmental challenges to face in the next decennia. Emission of CO₂, related to the use of fossil fuels, is believed to be one of the main causes of global warming and climate change. In this scenario, the production of biomethane from organic waste, as a renewable energy source, is one of the most promising strategies to reduce fossil fuel consumption and greenhouse gas emission. Unfortunately, biogas upgrading still produces the greenhouse gas CO₂ as a waste product. Therefore, this work presents a case study on biogas upgrading, aimed at the simultaneous purification of methane and CO₂ via different steps, including CO₂/methane separation by polymeric membranes. The original objective of the project was the biogas upgrading to distribution grid quality methane, but the innovative aspect of this case study is the further purification of the captured CO₂, transforming it from a useless by-product to a pure gas with food-grade quality, suitable for commercial application in the food and beverage industry. The study was performed on a pilot plant constructed by Tecno Project Industriale Srl (TPI) Italy. This is a model of one of the largest biogas production and purification plants. The full-scale anaerobic digestion plant (Montello Spa, North Italy), has a digestive capacity of 400.000 ton of biomass/year and can treat 6.250 m3/hour of biogas from FORSU (organic fraction of solid urban waste). The entire upgrading process consists of a number of purifications steps: 1. Dehydration of the raw biogas by condensation. 2. Removal of trace impurities such as H₂S via absorption. 3.Separation of CO₂ and methane via a membrane separation process. 4. Removal of trace impurities from CO₂. The gas separation with polymeric membranes guarantees complete simultaneous removal of microorganisms. The chemical purity of the different process streams was analysed by a certified laboratory and was compared with the guidelines of the European Industrial Gases Association and the International Society of Beverage Technologists (EIGA/ISBT) for CO₂ used in the food industry. The microbiological purity was compared with the limit values defined in the European Collaborative Action. With a purity of 96-99 vol%, the purified methane respects the legal requirements for the household network. At the same time, the CO₂ reaches a purity of > 98.1% before, and 99.9% after the final distillation process. According to the EIGA/ISBT guidelines, the CO₂ proves to be chemically and microbiologically sufficiently pure to be suitable for food-grade applications.Keywords: biogas, CO₂ separation, CO2 utilization, CO₂ food grade
Procedia PDF Downloads 2121542 Spray Drying and Physico-Chemical Microbiological Evaluation of Ethanolic Extracts of Propolis
Authors: David Guillermo Piedrahita Marquez, Hector Suarez Mahecha, Jairo Humberto Lopez
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The propolis are substances obtained from the beehive have an action against pathogens, prooxidant substances and free radicals because of its polyphenols content, this has motivated the use of these compounds in the food and pharmaceutical industries. However, due to their organoleptic properties and their ability to react with other compounds, their application has been limited; therefore, the objective of this research was to propose a mechanism to protect propolis and mitigate side effects granted by its components. To achieve the stated purpose ethanolic extracts of propolis (EEP) from three samples from Santander were obtained and their antioxidant and antimicrobial activity were evaluated in order to choose the extract with the biggest potential. Subsequently mixtures of the extract with maltodextrin were prepared by spray drying varying concentration and temperature, finally the yield, the physicochemical, and antioxidant properties of the products were measured. It was concluded that Socorro propolis was the best for the production of microencapsulated due to their activity against pathogenic strains, for its large percentage of DPPH radical inactivation and for its high phenolic content. In spray drying, the concentration of bioactive had a greater impact than temperature and the conditions set allowed a good performance and the production of particles with high antioxidant potential and little chance of proliferation of microorganisms. Also, it was concluded that the best conditions that allowed us to obtain the best particles were obtained after drying a mixture 1:2 ( EEP: Maltodextrin), besides the concentration is the most important variable in the spray drying process, at the end we obtained particles of different sizes and shape and the uniformity of the surface depend on the temperature. After watching the previously mentioned microparticles by scanning electron microscopy (SEM) it was concluded that most of the particles produced during the spray dry process had a spherical shape and presented agglomerations due to the moisture content of the ethanolic extracts of propolis (EEP), the morphology of the microparticles contributed to the stability of the final product and reduce the loss of total phenolic content.Keywords: spray drying, propolis, maltodextrin, encapsulation, scanning electron microscopy
Procedia PDF Downloads 2881541 Automatic Processing of Trauma-Related Visual Stimuli in Female Patients Suffering From Post-Traumatic Stress Disorder after Interpersonal Traumatization
Authors: Theresa Slump, Paula Neumeister, Katharina Feldker, Carina Y. Heitmann, Thomas Straube
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A characteristic feature of post-traumatic stress disorder (PTSD) is the automatic processing of disorder-specific stimuli that expresses itself in intrusive symptoms such as intense physical and psychological reactions to trauma-associated stimuli. That automatic processing plays an essential role in the development and maintenance of symptoms. The aim of our study was, therefore, to investigate the behavioral and neural correlates of automatic processing of trauma-related stimuli in PTSD. Although interpersonal traumatization is a form of traumatization that often occurs, it has not yet been sufficiently studied. That is why, in our study, we focused on patients suffering from interpersonal traumatization. While previous imaging studies on PTSD mainly used faces, words, or generally negative visual stimuli, our study presented complex trauma-related and neutral visual scenes. We examined 19 female subjects suffering from PTSD and examined 19 healthy women as a control group. All subjects did a geometric comparison task while lying in a functional-magnetic-resonance-imaging (fMRI) scanner. Trauma-related scenes and neutral visual scenes that were not relevant to the task were presented while the subjects were doing the task. Regarding the behavioral level, there were not any significant differences between the task performance of the two groups. Regarding the neural level, the PTSD patients showed significant hyperactivation of the hippocampus for task-irrelevant trauma-related stimuli versus neutral stimuli when compared with healthy control subjects. Connectivity analyses revealed altered connectivity between the hippocampus and other anxiety-related areas in PTSD patients, too. Overall, those findings suggest that fear-related areas are involved in PTSD patients' processing of trauma-related stimuli even if the stimuli that were used in the study were task-irrelevant.Keywords: post-traumatic stress disorder, automatic processing, hippocampus, functional magnetic resonance imaging
Procedia PDF Downloads 2001540 Chemical Aging of High-Density Polyethylene (HDPE-100) in Interaction with Aggressive Environment
Authors: Berkas Khaoula, Chaoui Kamel
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Polyethylene (PE) pipes are one of the best options for water and gas transmission networks. The main reason for such a choice is its high-quality performance in service conditions over long periods of time. PE pipes are installed in contact with different soils having various chemical compositions with confirmed aggressiveness. As a result, PE pipe surfaces undergo unwanted oxidation reactions. Usually, the polymer mixture is designed to include some additives, such as anti-oxidants, to inhibit or reduce the degradation effects. Some other additives are intended to increase resistance to the ESC phenomenon associated with polymers (ESC: Environmental Stress Cracking). This situation occurs in contact with aggressive external environments following different contaminations of soil, groundwater and transported fluids. In addition, bacterial activity and other physical or chemical media, such as temperature and humidity, can play an enhancing role. These conditions contribute to modifying the PE pipe structure and degrade its properties during exposure. In this work, the effect of distilled water, sodium hypochlorite (bleach), diluted sulfuric acid (H2SO4) and toluene-methanol (TM) mixture are studied when extruded PE samples are exposed to those environments for given periods. The chosen exposure periods are 7, 14 and 28 days at room temperature and in sealed glass containers. Post-exposure observations and ISO impact tests are presented as a function of time and chemical medium. Water effects are observed to be limited in explaining such use in real applications, whereas the changes in TM and acidic media are very significant. For the TM medium, the polymer toughness increased drastically (from 15.95 kJ/m² up to 32.01 kJ/m²), while sulfuric acid showed a steady augmentation over time. This situation may correspond to a hardening phenomenon of PE increasing its brittleness and its ability for structural degradation because of localized oxidation reactions and changes in crystallinity.Keywords: polyethylene, toluene-methanol mixture, environmental stress cracking, degradation, impact resistance
Procedia PDF Downloads 761539 Effectiveness of Metacognitive Skills in Comprehension Instruction for Elementary Students
Authors: Mahdi Taheri Asl
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Using a variety of strategies to read text plays an important role to make students strategic independent, strategic, and metacognitive readers. Given the importance of comprehension instruction (CI), it is essential to support the fostering comprehension skills at elementary age students, particularly those who struggle with or dislike reading. One of the main components of CI is activating metacognitive skills, which double function of elementary students. Thus, it’s important to evaluate the implemented comprehension interventions to inform reading specialist and teachers. There has been limited review research in the area of CI, so the conduction review research is required. The purpose of this review is to examine the effectiveness of metacognitive reading strategies in a regular classroom environment with elementary aged students. We develop five inclusion criteria to identify researches relevant to our research. First, the article had to be published in a peer-reviewed journal from 2000 to 2023. second, the study had to include participants in elementary school it could include of special education students. Third, the intervention needed to be involved with metacognitive strategies. Fourth, the articles had to use experimental or quasi experimental design. The last one needed to include measurement of reading performance in pre and post intervention. We used computer data-based site like Eric, PsychoINFO, and google scholar to search for articles that met these criteria. we used the following search terms: comprehension instruction, meta cognitive strategies, and elementary school. The next step was to do an ancestral search that get in reviewing the relevant studies cited in the articles that were found in the database search. We identified 30studies in the initial searches. After coding agreement, we synthesized 13 with respect to the participant, setting, research design, dependent variables, measures, the intervention used by instructors, and general outcomes. The finding show metacognitive strategies were effective to empower student’s comprehension skills. It also showed that linguistic instruction will be effective if got mixed with metacognitive strategies. The research provides a useful view into reading intervention. Despite the positive effect of metacognitive instruction on students’ comprehension skills, it is not widely used in classroom.Keywords: comprehension instruction, metacogntion, metacognitive skills, reading intervention
Procedia PDF Downloads 731538 Natural Monopolies and Their Regulation in Georgia
Authors: Marina Chavleishvili
Abstract:
Introduction: Today, the study of monopolies, including natural monopolies, is topical. In real life, pure monopolies are natural monopolies. Natural monopolies are used widely and are regulated by the state. In particular, the prices and rates are regulated. The paper considers the problems associated with the operation of natural monopolies in Georgia, in particular, their microeconomic analysis, pricing mechanisms, and legal mechanisms of their operation. The analysis was carried out on the example of the power industry. The rates of natural monopolies in Georgia are controlled by the Georgian National Energy and Water Supply Regulation Commission. The paper analyzes the positive role and importance of the regulatory body and the issues of improving the legislative base that will support the efficient operation of the branch. Methodology: In order to highlight natural monopolies market tendencies, the domestic and international markets are studied. An analysis of monopolies is carried out based on the endogenous and exogenous factors that determine the condition of companies, as well as the strategies chosen by firms to increase the market share. According to the productivity-based competitiveness assessment scheme, the segmentation opportunities, business environment, resources, and geographical location of monopolist companies are revealed. Main Findings: As a result of the analysis, certain assessments and conclusions were made. Natural monopolies are quite a complex and versatile economic element, and it is important to specify and duly control their frame conditions. It is important to determine the pricing policy of natural monopolies. The rates should be transparent, should show the level of life in the country, and should correspond to the incomes. The analysis confirmed the significance of the role of the Antimonopoly Service in the efficient management of natural monopolies. The law should adapt to reality and should be applied only to regulate the market. The present-day differential electricity tariffs varying depending on the consumed electrical power need revision. The effects of the electricity price discrimination are important, segmentation in different seasons in particular. Consumers use more electricity in winter than in summer, which is associated with extra capacities and maintenance costs. If the price of electricity in winter is higher than in summer, the electricity consumption will decrease in winter. The consumers will start to consume the electricity more economically, what will allow reducing extra capacities. Conclusion: Thus, the practical realization of the views given in the paper will contribute to the efficient operation of natural monopolies. Consequently, their activity will be oriented not on the reduction but on the increase of increments of the consumers or producers. Overall, the optimal management of the given fields will allow for improving the well-being throughout the country. In the article, conclusions are made, and the recommendations are developed to deliver effective policies and regulations toward the natural monopolies in Georgia.Keywords: monopolies, natural monopolies, regulation, antimonopoly service
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