Search results for: renewable energy technology
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 14893

Search results for: renewable energy technology

1513 Copper Phthalocyanine Nanostructures: A Potential Material for Field Emission Display

Authors: Uttam Kumar Ghorai, Madhupriya Samanta, Subhajit Saha, Swati Das, Nilesh Mazumder, Kalyan Kumar Chattopadhyay

Abstract:

Organic semiconductors have gained potential interest in the last few decades for their significant contributions in the various fields such as solar cell, non-volatile memory devices, field effect transistors and light emitting diodes etc. The most important advantages of using organic materials are mechanically flexible, light weight and low temperature depositing techniques. Recently with the advancement of nanoscience and technology, one dimensional organic and inorganic nanostructures such as nanowires, nanorods, nanotubes have gained tremendous interests due to their very high aspect ratio and large surface area for electron transport etc. Among them, self-assembled organic nanostructures like Copper, Zinc Phthalocyanine have shown good transport property and thermal stability due to their π conjugated bonds and π-π stacking respectively. Field emission properties of inorganic and carbon based nanostructures are reported in literatures mostly. But there are few reports in case of cold cathode emission characteristics of organic semiconductor nanostructures. In this work, the authors report the field emission characteristics of chemically and physically synthesized Copper Phthalocyanine (CuPc) nanostructures such as nanowires, nanotubes and nanotips. The as prepared samples were characterized by X-Ray diffraction (XRD), Ultra Violet Visible Spectrometer (UV-Vis), Fourier Transform Infra-red Spectroscopy (FTIR), and Field Emission Scanning Electron Microscope (FESEM) and Transmission Electron Microscope (TEM). The field emission characteristics were measured in our home designed field emission set up. The registered turn-on field and local field enhancement factor are found to be less than 5 V/μm and greater than 1000 respectively. The field emission behaviour is also stable for 200 minute. The experimental results are further verified by theoretically using by a finite displacement method as implemented in ANSYS Maxwell simulation package. The obtained results strongly indicate CuPc nanostructures to be the potential candidate as an electron emitter for field emission based display device applications.

Keywords: organic semiconductor, phthalocyanine, nanowires, nanotubes, field emission

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1512 Post-harvest Handling Practices and Technologies Harnessed by Smallholder Fruit Crop Farmers in Vhembe District, Limpopo Province, South Africa

Authors: Vhahangwele Belemu, Isaac Busayo Oluwatayo

Abstract:

Post-harvest losses pose a serious challenge to smallholder fruit crop farmers, especially in the rural communities of South Africa, affecting their economic livelihoods and food security. This study investigated the post-harvest handling practices and technologies harnessed by smallholder fruit crop farmers in the Vhembe district of Limpopo province, South Africa. Data were collected on a random sample of 224 smallholder fruit crop farmers selected from the four municipalities of the district using a multistage sampling technique. Analytical tools employed include descriptive statistics and the tobit regression model. A descriptive analysis of farmers’ socioeconomic characteristics showed that a sizeable number of these farmers are still in their active working age (mean = 52 years) with more males (63.8%) than their female (36.2%) counterparts. Respondents’ distribution by educational status revealed that only a few of these had no formal education (2.2%), with the majority having secondary education (48.7%). Results of data analysis further revealed that the prominent post-harvest technologies and handling practices harnessed by these farmers include using appropriate harvesting techniques (20.5%), selling at a reduced price (19.6%), transportation consideration (18.3%), cleaning and disinfecting (17.9%), sorting and grading (16.5%), manual cleaning (15.6%) and packaging technique (11.6%) among others. The result of the Tobit regression analysis conducted to examine the determinants of post-harvest technologies and handling practices harnessed showed that age, educational status of respondents, awareness of technology/handling practices, farm size, access to credit, extension contact, and membership of association were the significant factors. The study suggests enhanced awareness creation, access to credit facility and improved access to market as important factors to consider by relevant stakeholders to assist smallholder fruit crop farmers in the study area.

Keywords: fruit crop farmers, handling practices, post harvest losses, smallholder, Vhembe District, South Africa

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1511 Effluent from Royal LERD Wastewater Treatment Systems to Furnish Nutrients for Phytoplankton to Generate the Abundance of Hard Clam (Meretrix spp.) on Muddy Beach

Authors: O. Phewnil, S. Khowhit, W. Inkapatanakul, A. Boutson, K. Chunkao, O. Chueawong, T. Pattamapitoon, N. Chanwong, C. Nimpee

Abstract:

The King’s Royally Initiated Laem Phak Bia Environmental Research and Development Project (“the Royal LERD Project”) is located in Laem Phak Bia Sub-District, Ban Laem District, Phetchaburi Province, Thailand. Phetchaburi municipal wastewater was treated with a simple technology by using aquatic plants, constructed wetland, oxidation ponds through a nature-by-nature process. The effluent from the Royal LERD Project was discharged into Laem Phak Bia muddy beach. The soil sediment samples were collected from two zones (200 and 600 meters from the coast of the beach), and tested for cation-exchange capacity (CEC), pH and organic matter and soil particles content. The marine water samples were also collected from the beach in wet and dry seasons and analyzed for its quality and compositions, including but not limited to, biochemical oxygen demand (BOD), dissolved oxygen (DO), suspended solids (SS), nutrients, heavy metals (As, Cd, Cr, Hg, and Pb), and phytoplankton at high and low tides. The soil texture was sandy loam with high concentration of calcium and magnesium which showed a property of base (pH 8). The marine water was qualified with the standard limits of coastal water quality. A dominant species was Coscinodiscus sp. It was found approximately 70.46% of total phytoplankton species in Meretrix casta gastrointestinal tract. The concentration of the heavy metals (As, Cd, Cr, Hg, Ni and Pb) in the tissues and water content of two species of hard clams indicated that heavy metals in Meretrix casta were higher than those in Meretrix meretrix. However, the heavy metals in both species were under the standard limits and safe for consumption. It can be concluded that nutrients in effluent from the wastewater treatment systems play important role in promoting the growth of phytoplankton and generating abundance of hard clams on muddy beach.

Keywords: wastewater, phytoplankton, hard clam (Meretrix spp.), muddy beach

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1510 Experiential Language Learning as a Tool for Effective Global Leadership

Authors: Christiane Dumont

Abstract:

This paper proposes to revisit foreign-language learning as a tool to increase motivation through advocacy and develop effective natural communication skills, which are critical leadership qualities. To this end, collaborative initiatives undertaken by advanced university students of French with local and international community partners will be reviewed. Close attention will be paid to the acquisition of intercultural skills, the reflective process, as well as the challenges and outcomes. Two international development projects conducted in Haiti will be highlighted, i.e., collaboration with a network of providers in the Haitian cultural heritage preservation and tourism sector (2014-15) and development of investigation and teacher training tools for a primary/secondary school in the Port-au-Prince area (current). The choice of community-service learning as a framework to teach French-as-a-second-language stemmed from the need to raise awareness against stereotypes and prejudice, which hinder the development of effective intercultural skills. This type of experiential education also proved very effective in identifying and preventing miscommunication caused by the lack of face-to-face interaction in our increasingly technology-mediated world. Learners experienced first-hand, the challenges and advantages of face-to-face communication, which, in turn, enhanced their motivation for developing effective intercultural skills. Vygotsky's and Kolb's theories, current research on service learning (Dwight, Eyler), action/project-based pedagogy (Beckett), and reflective learning (TSC Farrell), will provide useful background to analyze the benefits and challenges of community-service learning. The ultimate goal of this paper is to find out what makes experiential learning truly unique and transformative for both the learners and the community they wish to serve. It will demonstrate how enhanced motivation, community engagement, and clear, concise, and respectful communication impact and empower learners. The underlying hope is to help students in high-profile, and leading-edge industries become effective global leaders.

Keywords: experiential learning, intercultural communication, reflective learning, effective leadership, learner motivation

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1509 Different Stages for the Creation of Electric Arc Plasma through Slow Rate Current Injection to Single Exploding Wire, by Simulation and Experiment

Authors: Ali Kadivar, Kaveh Niayesh

Abstract:

This work simulates the voltage drop and resistance of the explosion of copper wires of diameters 25, 40, and 100 µm surrounded by 1 bar nitrogen exposed to a 150 A current and before plasma formation. The absorption of electrical energy in an exploding wire is greatly diminished when the plasma is formed. This study shows the importance of considering radiation and heat conductivity in the accuracy of the circuit simulations. The radiation of the dense plasma formed on the wire surface is modeled with the Net Emission Coefficient (NEC) and is mixed with heat conductivity through PLASIMO® software. A time-transient code for analyzing wire explosions driven by a slow current rise rate is developed. It solves a circuit equation coupled with one-dimensional (1D) equations for the copper electrical conductivity as a function of its physical state and Net Emission Coefficient (NEC) radiation. At first, an initial voltage drop over the copper wire, current, and temperature distribution at the time of expansion is derived. The experiments have demonstrated that wires remain rather uniform lengthwise during the explosion and can be simulated utilizing 1D simulations. Data from the first stage are then used as the initial conditions of the second stage, in which a simplified 1D model for high-Mach-number flows is adopted to describe the expansion of the core. The current was carried by the vaporized wire material before it was dispersed in nitrogen by the shock wave. In the third stage, using a three-dimensional model of the test bench, the streamer threshold is estimated. Electrical breakdown voltage is calculated without solving a full-blown plasma model by integrating Townsend growth coefficients (TdGC) along electric field lines. BOLSIG⁺ and LAPLACE databases are used to calculate the TdGC at different mixture ratios of nitrogen/copper vapor. The simulations show both radiation and heat conductivity should be considered for an adequate description of wire resistance, and gaseous discharges start at lower voltages than expected due to ultraviolet radiation and the exploding shocks, which may have ionized the nitrogen.

Keywords: exploding wire, Townsend breakdown mechanism, streamer, metal vapor, shock waves

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1508 Composition Dependence of Ni 2p Core Level Shift in Fe1-xNix Alloys

Authors: Shakti S. Acharya, V. R. R. Medicherla, Rajeev Rawat, Komal Bapna, Deepnarayan Biswas, Khadija Ali, K. Maiti

Abstract:

The discovery of invar effect in 35% Ni concentration Fe1-xNix alloy has stimulated enormous experimental and theoretical research. Elemental Fe and low Ni concentration Fe1-xNix alloys which possess body centred cubic (bcc) crystal structure at ambient temperature and pressure transform to hexagonally close packed (hcp) phase at around 13 GPa. Magnetic order was found to be absent at 11K for Fe92Ni8 alloy when subjected to a high pressure of 26 GPa. The density functional theoretical calculations predicted substantial hyperfine magnetic fields, but were not observed in Mossbaur spectroscopy. The bulk modulus of fcc Fe1-xNix alloys with Ni concentration more than 35%, is found to be independent of pressure. The magnetic moment of Fe is also found be almost same in these alloys from 4 to 10 GPa pressure. Fe1-xNix alloys exhibit a complex microstructure which is formed by a series of complex phase transformations like martensitic transformation, spinodal decomposition, ordering, mono-tectoid reaction, eutectoid reaction at temperatures below 400°C. Despite the existence of several theoretical models the field is still in its infancy lacking full knowledge about the anomalous properties exhibited by these alloys. Fe1-xNix alloys have been prepared by arc melting the high purity constituent metals in argon ambient. These alloys have annealed at around 3000C in vacuum sealed quartz tube for two days to make the samples homogeneous. These alloys have been structurally characterized by x-ray diffraction and were found to exhibit a transition from bcc to fcc for x > 0.3. Ni 2p core levels of the alloys have been measured using high resolution (0.45 eV) x-ray photoelectron spectroscopy. Ni 2p core level shifts to lower binding energy with respect to that of pure Ni metal giving rise to negative core level shifts (CLSs). Measured CLSs exhibit a linear dependence in fcc region (x > 0.3) and were found to deviate slightly in bcc region (x < 0.3). ESCA potential model fails correlate CLSs with site potentials or charges in metallic alloys. CLSs in these alloys occur mainly due to shift in valence bands with composition due to intra atomic charge redistribution.

Keywords: arc melting, core level shift, ESCA potential model, valence band

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1507 Molecular Characterisation and Expression of Glutathione S-Transferase of Fasciola Gigantica

Authors: J. Adeppa, S. Samanta, O. K. Raina

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Fasciolosis is a widespread economically important parasitic infection throughout the world caused by Fasciola hepatica and F. gigantica. In order to identify novel immunogen conferring significant protection against fasciolosis, currently, research has been focused on the defined antigens viz. glutathione S-transferase, fatty acid binding protein, cathepsin-L, fluke hemoglobin, paramyosin, myosin and F. hepatica- Kunitz Type Molecule. Among various antigens, GST which plays a crucial role in detoxification processes, i.e. phase II defense mechanism of this parasite, has a unique position as a novel vaccine candidate and a drug target in the control of this disease. For producing the antigens in large quantities and their purification to complete homogeneity, the recombinant DNA technology has become an important tool to achieve this milestone. RT- PCR was carried out using F. gigantica total RNA as template, and an amplicon of 657 bp GST gene was obtained. TA cloning vector was used for cloning of this gene, and the presence of insert was confirmed by blue-white selection for recombinant colonies. Sequence analysis of the present isolate showed 99.1% sequence homology with the published sequence of the F. gigantica GST gene of cattle origin (accession no. AF112657), with six nucleotide changes at 72, 74, 423, 513, 549 and 627th bp found in the present isolate, causing an overall change of 4 amino acids. The 657 bp GST gene was cloned at BamH1 and HindIII restriction sites of the prokaryotic expression vector pPROEXHTb in frame with six histidine residues and expressed in E. coli DH5α. Recombinant protein was purified from the bacterial lysate under non-denaturing conditions by the process of sonication after lysozyme treatment and subjecting the soluble fraction of the bacterial lysate to Ni-NTA affinity chromatography. Western blotting with rabbit hyper-immune serum showed immuno-reactivity with 25 kDa recombinant GST. Recombinant protein detected F. gigantica experimental as well as field infection in buffaloes by dot-ELISA. However, cross-reactivity studies on Fasciola gigantica GST antigen are needed to evaluate the utility of this protein in the serodiagnosis of fasciolosis.

Keywords: fasciola gigantic, fasciola hepatica, GST, RT- PCR

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1506 Safe Disposal of Pyrite Rich Waste Rock Using Alkali Phosphate Treatment

Authors: Jae Gon Kim, Yongchan Cho, Jungwha Lee

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Acid rock drainage (ARD) is generated by the oxidation of pyrite (FeS₂) contained in the excavated rocks upon its exposure to atmosphere and is an environmental concern at construction site due to its high acidity and high concentration of toxic elements. We developed the safe disposal method with the reduction of ARD generation by an alkali phosphate treatment. A pyrite rich andesite was collected from a railway construction site. The collected rock sample was crushed to be less than 3/8 inches in diameter using a jaw crusher. The crushed rock was filled in an acryl tube with 20 cm in diameter and 40 cm in height. Two treatments for the ARD reduction were conducted with duplicates: 1) the addition of 10mM KH₂PO₄_3% NaHCO₃ and 2) the addition of 10mM KH₂PO₄_3% NaHCO₃ and ordinary portland cement (OPC) on the top of the column. After the treatments, 500 ml of distilled water added to each column for every week for 3 weeks and then the column was flushed with 1,500 ml of distilled water in the 4th week. The pH, electrical conductivity (EC), concentrations of anions and cations of the leachates were monitored for 10 months. The pH of the leachates from the untreated column showed 2.1-3.7, but the leachates from the columns treated with the alkali phosphate solution with or without the OPC addition showed pH 6.7–8.9. The leachates from the treated columns had much lower concentrations of SO₄²⁻ and toxic elements such as Al, Mn, Fe and heavy metals than those from the untreated columns. However, the leachates from the treated columns had a higher As concentration than those from the untreated columns. There was no significant difference in chemical property between the leachates from the treated columns with and without the OPC addition. The chemistry of leachates indicates that the alkali phosphate treatment decreased the oxidation of sulfide and neutralized the acidic pore water. No significant effect of the OPC addition on the leachate chemistry has shown during 10-month experiment. However, we expect a positive effect of the OPC addition on the reduction of ARD generation in terms of long period. According to the results of this experiment, the alkali phosphate treatment of sulfide rich rock can be a promising technology for the safe disposal method with the ARD reduction.

Keywords: acid rock drainage, alkali phosphate treatment, pyrite rich rock, safe disposal

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1505 Dynamic Ambulance Deployment to Reduce Ambulance Response Times Using Geographic Information Systems

Authors: Masoud Swalehe, Semra Günay

Abstract:

Developed countries are losing many lives to non-communicable diseases as compared to their developing counterparts. The effects of these diseases are mostly sudden and manifest at a very short time prior to death or a dangerous attack and this has consolidated the significance of emergency medical system (EMS) as one of the vital areas of healthcare service delivery. The primary objective of this research is to reduce ambulance response times (RT) of Eskişehir province EMS since a number of studies have established a relationship between ambulance response times and survival chances of patients especially out of hospital cardiac arrest (OHCA) victims. It has been found out that patients who receive out of hospital medical attention in few (4) minutes after cardiac arrest because of low ambulance response times stand higher chances of survival than their counterparts who take longer times (more than 12 minutes) to receive out of hospital medical care because of higher ambulance response times. The study will make use of geographic information systems (GIS) technology to dynamically reallocate ambulance resources according to demand and time so as to reduce ambulance response times. Geospatial-time distribution of ambulance calls (demand) will be used as a basis for optimal ambulance deployment using system status management (SSM) strategy to achieve much demand coverage with the same number of ambulance resources to cause response time reduction. Drive-time polygons will be used to come up with time specific facility coverage areas and suggesting additional facility candidate sites where ambulance resources can be moved to serve higher demands making use of network analysis techniques. Emergency Ambulance calls’ data from 1st January 2014 to 31st December 2014 obtained from Eskişehir province health directorate will be used in this study. This study will focus on the reduction of ambulance response times which is a key Emergency Medical Services performance indicator.

Keywords: emergency medical services, system status management, ambulance response times, geographic information system, geospatial-time distribution, out of hospital cardiac arrest

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1504 The Incidence of Obesity among Adult Women in Pekanbaru City, Indonesia, Related to High Fat Consumption, Stress Level, and Physical Activity

Authors: Yudia Mailani Putri, Martalena Purba, B. J. Istiti Kandarina

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Background: Obesity has been recognized as a global health problem. Individuals classified as overweight and obese are increasing at an alarming rate. This condition is associated with psychological and physiological problems. as a person reaches adulthood, somatic growth ceases. At this stage, the human body has developed fully, to a stable state. As the capital of Riau Province in Indonesia, Pekanbaru is dominated by Malay ethnic population habitually consuming cholesterol-rich fatty foods as a daily menu, a trigger to the onset of obesity resulting in high prevalence of degenerative diseases. Research objectives: The aim of this study is elaborating the relationship between high-fat consumption pattern, stress level, physical activity and the incidence of obesity in adult women in Pekanbaru city. Research Methods: Among the combined research methods applied in this study, the first stage is quantitative observational, analytical cross-sectional research design with adult women aged 20-40 living in Pekanbaru city. The sample consists of 200 women with BMI≥25. Sample data is processed with univariate, bivariate (correlation and simple linear regression) and multivariate (multiple linear regression) analysis. The second phase is qualitative descriptive study purposive sampling by in-depth interviews. six participants withdrew from the study. Results: According to the results of the bivariate analysis, there are relationships between the incidence of obesity and the pattern of high fat foods consumption (energy intake (p≤0.000; r = 0.536), protein intake (p≤0.000; r=0.307), fat intake (p≤0.000; r=0.416), carbohydrate intake (p≤0.000; r=0.430), frequency of fatty food consumption (p≤0.000; r=0.506) and frequency of viscera foods consumption (p≤0.000; r=0.535). There is a relationship between physical activity and incidence of obesity (p≤0.000; r=-0.631). However, there is no relationship between the level of stress (p=0.741; r=0.019-) and the incidence of obesity. Physical activity is a predominant factor in the incidence of obesity in adult women in Pekanbaru city. Conclusion: There are relationships between high-fat food consumption pattern, physical activity and the incidence of obesity in Pekanbaru city whereas physical activity is a predominant factor in the occurrence of obesity, supported by the unchangeable pattern of high-fat foods consumption.

Keywords: obesity, adult, high in fat, stress, physical activity, consumption pattern

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1503 Recovery of Physical Performance in Postpartum Women: An Effective Physical Education Program

Authors: Julia A. Ermakova

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This study aimed to investigate the efficacy of a physical rehabilitation program for postpartum women. The program was developed with the purpose of restoring physical performance in women during the postpartum period. The research employed a variety of methods, including an analysis of scientific literature, pedagogical testing and experimentation, mathematical processing of study results, and physical performance assessment using a range of tests. The program recommends refraining from abdominal exercises during the first 6-8 months following a cesarean section and avoiding exercises with weights. Instead, a feasible training regimen that gradually increases in intensity several times a week is recommended, along with moderate cardio exercises such as walking, bodyweight training, and a separate workout component that targets posture improvement. Stretching after strength training is also encouraged. The necessary equipment includes comfortable sports attire with a chest support top, mat, push-ups, resistance band, timer, and clock. The motivational aspect of the program is paramount, and the mentee's positive experience with the workout regimen includes feelings of lightness in the body, increased energy, and positive emotions. The gradual reduction of body size and weight loss due to an improved metabolism also serves as positive reinforcement. The mentee's progress can be measured through various means, including an external assessment of her form, body measurements, weight, BMI, and the presence or absence of slouching in everyday life. The findings of this study reveal that the program is effective in restoring physical performance in postpartum women. The mentee achieved weight loss and almost regained her pre-pregnancy shape while her self-esteem improved. Her waist, shoulder, and hip measurements decreased, and she displayed less slouching in her daily life. In conclusion, the developed physical rehabilitation program for postpartum women is an effective means of restoring physical performance. It is crucial to follow the recommended training regimen and equipment to avoid limitations and ensure safety during the postpartum period. The motivational component of the program is also fundamental in encouraging positive reinforcement and improving self-esteem.

Keywords: physical rehabilitation, postpartum, methodology, postpartum recovery, rehabilitation

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1502 Seismic Retrofit of Tall Building Structure with Viscous, Visco-Elastic, Visco-Plastic Damper

Authors: Nicolas Bae, Theodore L. Karavasilis

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Increasingly, a large number of new and existing tall buildings are required to improve their resilient performance against strong winds and earthquakes to minimize direct, as well as indirect damages to society. Those advent stationary functions of tall building structures in metropolitan regions can be severely hazardous, in socio-economic terms, which also increase the requirement of advanced seismic performance. To achieve these progressive requirements, the seismic reinforcement for some old, conventional buildings have become enormously costly. The methods of increasing the buildings’ resilience against wind or earthquake loads have also become more advanced. Up to now, vibration control devices, such as the passive damper system, is still regarded as an effective and an easy-to-install option, in improving the seismic resilience of buildings at affordable prices. The main purpose of this paper is to examine 1) the optimization of the shape of visco plastic brace damper (VPBD) system which is one of hybrid damper system so that it can maximize its energy dissipation capacity in tall buildings against wind and earthquake. 2) the verification of the seismic performance of the visco plastic brace damper system in tall buildings; up to forty-storey high steel frame buildings, by comparing the results of Non-Linear Response History Analysis (NLRHA), with and without a damper system. The most significant contribution of this research is to introduce the optimized hybrid damper system that is adequate for high rise buildings. The efficiency of this visco plastic brace damper system and the advantages of its use in tall buildings can be verified since tall buildings tend to be affected by wind load at its normal state and also by earthquake load after yielding of steel plates. The modeling of the prototype tall building will be conducted using the Opensees software. Three types of modeling were used to verify the performance of the damper (MRF, MRF with visco-elastic, MRF with visco-plastic model) 22-set seismic records used and the scaling procedure was followed according to the FEMA code. It is shown that MRF with viscous, visco-elastic damper, it is superior effective to reduce inelastic deformation such as roof displacement, maximum story drift, roof velocity compared to the MRF only.

Keywords: tall steel building, seismic retrofit, viscous, viscoelastic damper, performance based design, resilience based design

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1501 Effect of Damper Combinations in Series or Parallel on Structural Response

Authors: Ajay Kumar Sinha, Sharad Singh, Anukriti Sinha

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Passive energy dissipation method for earthquake protection of structures is undergoing developments for improved performance. Combined use of different types of damping mechanisms has shown positive results in the near past. Different supplemental damping methods like viscous damping, frictional damping and metallic damping are being combined together for optimum performance. The conventional method of connecting passive dampers to structures is a parallel connection between the damper unit and structural member. Researchers are investigating coupling effect of different types of dampers. The most popular choice among the research community is coupling of viscous dampers and frictional dampers. The series and parallel coupling of these damping units are being studied for relative performance of the coupled system on response control of structures against earthquake. In this paper an attempt has been made to couple Fluid Viscous Dampers and Frictional Dampers in series and parallel to form a single unit of damping system. The relative performance of the coupled units has been studied on three dimensional reinforced concrete framed structure. The current theories of structural dynamics in practice for viscous damping and frictional damping have been incorporated in this study. The time history analysis of the structural system with coupled damper units, uncoupled damper units as well as of structural system without any supplemental damping has been performed in this study. The investigations reported in this study show significant improved performance of coupled system. A higher natural frequency of the system outside the forcing frequency has been obtained for structural systems with coupled damper units as against the other cases. The structural response of the structure in terms of storey displacement and storey drift show significant improvement for the case with coupled damper units as against the cases with uncoupled units or without any supplemental damping. The results are promising in terms of improved response of the structure with coupled damper units. Further investigations in this regard for a comparative performance of the series and parallel coupled systems will be carried out to study the optimum behavior of these coupled systems for enhanced response control of structural systems.

Keywords: frictional damping, parallel coupling, response control, series coupling, supplemental damping, viscous damping

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1500 The Psychometric Properties of an Instrument to Estimate Performance in Ball Tasks Objectively

Authors: Kougioumtzis Konstantin, Rylander Pär, Karlsteen Magnus

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Ball skills as a subset of fundamental motor skills are predictors for performance in sports. Currently, most tools evaluate ball skills utilizing subjective ratings. The aim of this study was to examine the psychometric properties of a newly developed instrument to objectively measure ball handling skills (BHS-test) utilizing digital instrument. Participants were a convenience sample of 213 adolescents (age M = 17.1 years, SD =3.6; 55% females, 45% males) recruited from upper secondary schools and invited to a sports hall for the assessment. The 8-item instrument incorporated both accuracy-based ball skill tests and repetitive-performance tests with a ball. Testers counted performance manually in the four tests (one throwing and three juggling tasks). Furthermore, assessment was technologically enhanced in the other four tests utilizing a ball machine, a Kinect camera and balls with motion sensors (one balancing and three rolling tasks). 3D printing technology was used to construct equipment, while all results were administered digitally with smart phones/tablets, computers and a specially constructed application to send data to a server. The instrument was deemed reliable (α = .77) and principal component analysis was used in a random subset (53 of the participants). Furthermore, latent variable modeling was employed to confirm the structure with the remaining subset (160 of the participants). The analysis showed good factorial-related validity with one factor explaining 57.90 % of the total variance. Four loadings were larger than .80, two more exceeded .76 and the other two were .65 and .49. The one factor solution was confirmed by a first order model with one general factor and an excellent fit between model and data (χ² = 16.12, DF = 20; RMSEA = .00, CI90 .00–.05; CFI = 1.00; SRMR = .02). The loadings on the general factor ranged between .65 and .83. Our findings indicate good reliability and construct validity for the BHS-test. To develop the instrument further, more studies are needed with various age-groups, e.g. children. We suggest using the BHS-test for diagnostic or assessment purpose for talent development and sports participation interventions that focus on ball games.

Keywords: ball-handling skills, ball-handling ability, technologically-enhanced measurements, assessment

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1499 Economics of Sugandhakokila (Cinnamomum Glaucescens (Nees) Dury) in Dang District of Nepal: A Value Chain Perspective

Authors: Keshav Raj Acharya, Prabina Sharma

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Sugandhakokila (Cinnamomum glaucescens Nees. Dury) is a large evergreen native tree species; mostly confined naturally in mid-hills of Rapti Zone of Nepal. The species is identified as prioritized for agro-technology development as well as for research and development by a department of plant resources. This species is band for export outside the country without processing by the government of Nepal to encourage the value addition within the country. The present study was carried out in Chillikot village of Dang district to find out the economic contribution of C. glaucescens in the local economy and to document the major conservation threats for this species. Participatory Rural Appraisal (PRA) tools such as Household survey, key informants interviews and focus group discussions were carried out to collect the data. The present study reveals that about 1.7 million Nepalese rupees (NPR) have been contributed annually in the local economy of 29 households from the collection of C. glaucescens berries in the study area. The average annual income of each family was around NPR 67,165.38 (US$ 569.19) from the sale of the berries which contributes about 53% of the total household income. Six different value chain actors are involved in C. glaucescens business. Maximum profit margin was taken by collector followed by producer, exporter and processor. The profit margin was found minimum to regional and village traders. The total profit margin for producers was NPR 138.86/kg, and regional traders have gained NPR 17/kg. However, there is a possibility to increase the profit of producers by NPR 8.00 more for each kg of berries through the initiation of community forest user group and village cooperatives in the area. Open access resource, infestation by an insect to over matured trees and browsing by goats were identified as major conservation threats for this species. Handing over the national forest as a community forest, linking the producers with the processor through organized market channel and replacing the old tree through new plantation has been recommended for future.

Keywords: community forest, conservation threats, C. glaucescens, value chain analysis

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1498 Safety-critical Alarming Strategy Based on Statistically Defined Slope Deformation Behaviour Model Case Study: Upright-dipping Highwall in a Coal Mining Area

Authors: Lintang Putra Sadewa, Ilham Prasetya Budhi

Abstract:

Slope monitoring program has now become a mandatory campaign for any open pit mines around the world to operate safely. Utilizing various slope monitoring instruments and strategies, miners are now able to deliver precise decisions in mitigating the risk of slope failures which can be catastrophic. Currently, the most sophisticated slope monitoring technology available is the Slope Stability Radar (SSR), whichcan measure wall deformation in submillimeter accuracy. One of its eminent features is that SSRcan provide a timely warning by automatically raise an alarm when a predetermined rate-of-movement threshold is reached. However, establishing proper alarm thresholds is arguably one of the onerous challenges faced in any slope monitoring program. The difficulty mainly lies in the number of considerations that must be taken when generating a threshold becausean alarm must be effectivethat it should limit the occurrences of false alarms while alsobeing able to capture any real wall deformations. In this sense, experience shows that a site-specific alarm thresholdtendsto produce more reliable results because it considers site distinctive variables. This study will attempt to determinealarming thresholds for safety-critical monitoring based on an empirical model of slope deformation behaviour that is defined statistically fromdeformation data captured by the Slope Stability Radar (SSR). The study area comprises of upright-dipping highwall setting in a coal mining area with intense mining activities, andthe deformation data used for the study were recorded by the SSR throughout the year 2022. The model is site-specific in nature thus, valuable information extracted from the model (e.g., time-to-failure, onset-of-acceleration, and velocity) will be applicable in setting up site-specific alarm thresholds and will give a clear understanding of how deformation trends evolve over the area.

Keywords: safety-critical monitoring, alarming strategy, slope deformation behaviour model, coal mining

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1497 A Novel Application of CORDYCEPIN (Cordycepssinensis Extract): Maintaining Stem Cell Pluripotency and Improving iPS Generation Efficiency

Authors: Shih-Ping Liu, Cheng-Hsuan Chang, Yu-Chuen Huang, Shih-Yin Chen, Woei-Cherng Shyu

Abstract:

Embryonic stem cells (ES) and induced pluripotnet stem cells (iPS) are both pluripotent stem cells. For mouse stem cells culture technology, leukemia inhibitory factor (LIF) was used to maintain the pluripotency of stem cells in vitro. However, LIF is an expensive reagent. The goal of this study was to find out a pure compound extracted from Chinese herbal medicine that could maintain stem cells pluripotency to replace LIF and improve the iPS generation efficiency. From 20 candidates traditional Chinese medicine we found that Cordycepsmilitaris triggered the up-regulation of stem cells activating genes (Oct4 and Sox2) expression levels in MEF cells. Cordycepin, a major active component of Cordycepsmilitaris, also could up-regulate Oct4 and Sox2 gene expression. Furthermore, we used ES and iPS cells and treated them with different concentrations of Cordycepin (replaced LIF in the culture medium) to test whether it was useful to maintain the pluripotency. The results showed higher expression levels of several stem cells markers in 10 μM Cordycepin-treated ES and iPS cells compared to controls that did not contain LIF, including alkaline phosphatase, SSEA1, and Nanog. Embryonic body formation and differentiation confirmed that 10 μM Cordycepin-containing medium was capable to maintain stem cells pluripotency after four times passages. For mechanism analysis, microarray analysis indicated extracellular matrix and Jak/Stat signaling pathway as the top two deregulated pathways. In ECM pathway, we determined that the integrin αVβ5 expression levels and phosphorylated Src levels increased after Cordycepin treatment. In addition, the phosphorylated Jak2 and phosphorylated Sat3 protein levels were increased after Cordycepin treatment and suppressed with the Jak2 inhibitor, AG490. The expression of cytokines associated with Jak2/Stat3 signaling pathway were also up-regulated by Q-PCR and ELISA assay. Lastly, we used Oct4-GFP MEF cells to test iPS generation efficiency following Cordycepin treatment. We observed that 10 Μm Cordycepin significantly increased the iPS generation efficiency in day 21. In conclusion, we demonstrated Cordycepin could maintain the pluripotency of stem cells through both of ECM and Jak2/Stat3 signaling pathway and improved iPS generation efficiency.

Keywords: cordycepin, iPS cells, Jak2/Stat3 signaling pathway, molecular biology

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1496 Performance of Different Spray Nozzles in the Application of Defoliant on Cotton Plants (Gossypium hirsutum L.)

Authors: Mohamud Ali Ibrahim, Ali Bayat, Ali Bolat

Abstract:

Defoliant spraying is an important link in the mechanized cotton harvest because adequate and uniform spraying can improve defoliation quality and reduce cotton trash content. In defoliant application, application volume and spraying technology are extremely important. In this study, the effectiveness of defoliant application to cotton plant that has come to harvest with two different application volumes and three different types of nozzles with a standard field crop sprayer was determined. Experiments were carried in two phases as field area trials and laboratory analysis. Application rates were 250 l/ha and 400 L/ha, and spraying nozzles were (1) Standard flat fan nozzle (TP8006), (2) Air induction nozzle (AI 11002-VS), and (3) Dual Pattern nozzle (AI307003VP). A tracer (BSF) and defoliant were applied to mature cotton with approximately 60% open bolls and samplings for BSF deposition and spray coverage on the cotton plant were done at two plant height (upper layer, lower layer) of plant. Before and after spraying, bolls open and leaves rate on cotton plants were calculated, and filter papers were used to detect BSF deposition, and water sensitive papers (WSP) were used to measure the coverage rate of spraying methods used. Spectrofluorophotometer was used to detect the amount of tracer deposition on targets, and an image process computer programme was used to measure coverage rate on WSP. In analysis, conclusions showed that air induction nozzle (AI 11002-VS) achieved better results than the dual pattern and standard flat fan nozzles in terms of higher depositions, coverages, and leaf defoliations, and boll opening rates. AI nozzles operating at 250 L/ha application rate provide the highest deposition and coverage rate on applications of the defoliant; in addition, BSF as an indicator of the defoliant used reached on leaf beneath in merely this spray nozzle. After defoliation boll opening rate was 85% on the 7th and 12th days after spraying and falling rate of leaves was 76% at application rate of 250 L/ha with air induction (AI1102) nozzle.

Keywords: cotton defoliant, air induction nozzle, dual pattern nozzle, standard flat fan nozzle, coverage rate, spray deposition, boll opening rate, leaves falling rate

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1495 Different Approaches to Teaching a Database Course to Undergraduate and Graduate Students

Authors: Samah Senbel

Abstract:

Database Design is a fundamental part of the Computer Science and Information technology curricula in any school, as well as in the study of management, business administration, and data analytics. In this study, we compare the performance of two groups of students studying the same database design and implementation course at Sacred Heart University in the fall of 2018. Both courses used the same textbook and were taught by the same professor, one for seven graduate students and one for 26 undergraduate students (juniors). The undergraduate students were aged around 20 years old with little work experience, while the graduate students averaged 35 years old and all were employed in computer-related or management-related jobs. The textbook used was 'Database Systems, Design, Implementation, and Management' by Coronel and Morris, and the course was designed to follow the textbook roughly a chapter per week. The first 6 weeks covered the design aspect of a database, followed by a paper exam. The next 6 weeks covered the implementation aspect of the database using SQL followed by a lab exam. Since the undergraduate students are on a 16 week semester, we spend the last three weeks of the course covering NoSQL. This part of the course was not included in this study. After the course was over, we analyze the results of the two groups of students. An interesting discrepancy was observed: In the database design part of the course, the average grade of the graduate students was 92%, while that of the undergraduate students was 77% for the same exam. In the implementation part of the course, we observe the opposite: the average grade of the graduate students was 65% while that of the undergraduate students was 73%. The overall grades were quite similar: the graduate average was 78% and that of the undergraduates was 75%. Based on these results, we concluded that having both classes follow the same time schedule was not beneficial, and an adjustment is needed. The graduates could spend less time on design and the undergraduates would benefit from more design time. In the fall of 2019, 30 students registered for the undergraduate course and 15 students registered for the graduate course. To test our conclusion, the undergraduates spend about 67% of time (eight classes) on the design part of the course and 33% (four classes) on the implementation part, using the exact exams as the previous year. This resulted in an improvement in their average grades on the design part from 77% to 83% and also their implementation average grade from 73% to 79%. In conclusion, we recommend using two separate schedules for teaching the database design course. For undergraduate students, it is important to spend more time on the design part rather than the implementation part of the course. While for the older graduate students, we recommend spending more time on the implementation part, as it seems that is the part they struggle with, even though they have a higher understanding of the design component of databases.

Keywords: computer science education, database design, graduate and undergraduate students, pedagogy

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1494 Potential Contribution of Blue Oceans for Growth of Universities: Case of Faculties of Agriculture in Public Universities in Zimbabwe

Authors: Wonder Ngezimana, Benjamin Alex Madzivire

Abstract:

As new public universities are being applauded for being promulgated in Zimbabwe, there is need for comprehensive plan for ensuring sustainable competitive advantages in their niche mandated areas. Unhealthy competition between university faculties for enrolment hinders growth of the newly established universities faculties, especially in the agricultural sciences related disciplines. Blue ocean metaphor is based on creation of competitor-free market unlike 'red oceans', which are well explored and crowded with competitors. This study seeks to explore the potential contribution of blue oceans strategy (BOS) for growth of universities with bias towards faculties of agriculture in public universities in Zimbabwe. Case studies with agricultural sciences related disciplines were selected across three universities for interviewing. Data was collected through 10 open ended questions on academics in different management positions within university faculties of agriculture. Summative analysis was thereafter used during coding and interpretation of the data. Study findings show that there are several important elements for making offerings more comprehendible towards fostering faculty growth and performance with bias towards student enrolment. The results points towards BOS form of value innovations with various elements to consider in faculty offerings. To create valued innovation beyond the red oceans, the cases in this study have to be modelled to foster changes in enrolment, modes of delivery, certification, being research oriented with excellence in teaching, ethics, service to the community and entrepreneurship. There is, therefore, need to rethink strategy towards reshaping inclusive enrolment, industry relevance, affiliations, lifelong learning, sustainable student welfare, ubuntu, exchange programmes, research excellence, alumni support and entrepreneurship. Innovative strategic collaborations and partnerships, anchored on technology boost the strategic offerings henceforth leveraging on various offerings in this study. Areas of further study include the amplitude of blue oceans shown in the university faculty offerings and implementation strategies of BOS.

Keywords: blue oceans strategy, collaborations, faculty offerings, value innovations

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1493 Crime Prevention with Artificial Intelligence

Authors: Mehrnoosh Abouzari, Shahrokh Sahraei

Abstract:

Today, with the increase in quantity and quality and variety of crimes, the discussion of crime prevention has faced a serious challenge that human resources alone and with traditional methods will not be effective. One of the developments in the modern world is the presence of artificial intelligence in various fields, including criminal law. In fact, the use of artificial intelligence in criminal investigations and fighting crime is a necessity in today's world. The use of artificial intelligence is far beyond and even separate from other technologies in the struggle against crime. Second, its application in criminal science is different from the discussion of prevention and it comes to the prediction of crime. Crime prevention in terms of the three factors of the offender, the offender and the victim, following a change in the conditions of the three factors, based on the perception of the criminal being wise, and therefore increasing the cost and risk of crime for him in order to desist from delinquency or to make the victim aware of self-care and possibility of exposing him to danger or making it difficult to commit crimes. While the presence of artificial intelligence in the field of combating crime and social damage and dangers, like an all-seeing eye, regardless of time and place, it sees the future and predicts the occurrence of a possible crime, thus prevent the occurrence of crimes. The purpose of this article is to collect and analyze the studies conducted on the use of artificial intelligence in predicting and preventing crime. How capable is this technology in predicting crime and preventing it? The results have shown that the artificial intelligence technologies in use are capable of predicting and preventing crime and can find patterns in the data set. find large ones in a much more efficient way than humans. In crime prediction and prevention, the term artificial intelligence can be used to refer to the increasing use of technologies that apply algorithms to large sets of data to assist or replace police. The use of artificial intelligence in our debate is in predicting and preventing crime, including predicting the time and place of future criminal activities, effective identification of patterns and accurate prediction of future behavior through data mining, machine learning and deep learning, and data analysis, and also the use of neural networks. Because the knowledge of criminologists can provide insight into risk factors for criminal behavior, among other issues, computer scientists can match this knowledge with the datasets that artificial intelligence uses to inform them.

Keywords: artificial intelligence, criminology, crime, prevention, prediction

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1492 In Search of Commonalities in the Determinants of Child Sex Ratios in India and People's of Republic of China

Authors: Suddhasil Siddhanta, Debasish Nandy

Abstract:

Child sex ratios pattern in the Asian Population is highly masculine mainly due to birth masculinity and gender bias in child mortality. The vast and the growing literature of female deficit in world population points out the diffusion of child sex ratio pattern in many Asian as well as neighboring European countries. However, little attention has been given to understand the common factors in different demographics in explaining child sex ratio pattern. Such a scholarship is extremely important as level of gender inequity is different in different country set up. Our paper tries to explain the major structural commonalities in the child masculinity pattern in two demographic billionaires - India and China. The analysis reveals that apart from geographical diffusion of sex selection technology, patrilocal social structure, as proxied by households with more than one generation in China and proportion of population aged 65 years and above in India, can explain significant variation of missing girl child in these two countries. Even after controlling for individual capacity building factors like educational attainment, or work force participation, the measure of social stratification is coming out to be the major determinant of child sex ratio variation. Other socio economic factors that perform much well are the agency building factors of the females, like changing pattern of marriage customs which is proxied by divorce and remarriage ratio for china and percentage of female marrying at or after the age of 20 years in India and the female workforce participation. Proportion of minorities in socio-religious composition of the population and gender bias in scholastic attainment in both these counties are also found to be significant in modeling child sex ratio variations. All these significant common factors associated with child sex ratio point toward the one single most important factor: the historical evolution of patriarchy and its contemporary perpetuation in both the countries. It seems that prohibition of sex selection might not be sufficient to combat the peculiar skewness of excessive maleness in child population in both these countries. Demand sided policies is therefore utmost important to root out the gender bias in child sex ratios.

Keywords: child sex ratios, gender bias, structural factors, prosperity, patrilocality

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1491 IoT Based Soil Moisture Monitoring System for Indoor Plants

Authors: Gul Rahim Rahimi

Abstract:

The IoT-based soil moisture monitoring system for indoor plants is designed to address the challenges of maintaining optimal moisture levels in soil for plant growth and health. The system utilizes sensor technology to collect real-time data on soil moisture levels, which is then processed and analyzed using machine learning algorithms. This allows for accurate and timely monitoring of soil moisture levels, ensuring plants receive the appropriate amount of water to thrive. The main objectives of the system are twofold: to keep plants fresh and healthy by preventing water deficiency and to provide users with comprehensive insights into the water content of the soil on a daily and hourly basis. By monitoring soil moisture levels, users can identify patterns and trends in water consumption, allowing for more informed decision-making regarding watering schedules and plant care. The scope of the system extends to the agriculture industry, where it can be utilized to minimize the efforts required by farmers to monitor soil moisture levels manually. By automating the process of soil moisture monitoring, farmers can optimize water usage, improve crop yields, and reduce the risk of plant diseases associated with over or under-watering. Key technologies employed in the system include the Capacitive Soil Moisture Sensor V1.2 for accurate soil moisture measurement, the Node MCU ESP8266-12E Board for data transmission and communication, and the Arduino framework for programming and development. Additionally, machine learning algorithms are utilized to analyze the collected data and provide actionable insights. Cloud storage is utilized to store and manage the data collected from multiple sensors, allowing for easy access and retrieval of information. Overall, the IoT-based soil moisture monitoring system offers a scalable and efficient solution for indoor plant care, with potential applications in agriculture and beyond. By harnessing the power of IoT and machine learning, the system empowers users to make informed decisions about plant watering, leading to healthier and more vibrant indoor environments.

Keywords: IoT-based, soil moisture monitoring, indoor plants, water management

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1490 Fabrication and Characterisation of Additive Manufactured Ti-6Al-4V Parts by Laser Powder Bed Fusion Technique

Authors: Norica Godja, Andreas Schindel, Luka Payrits, Zsolt Pasztor, Bálint Hegedüs, Petr Homola, Jan Horňas, Jiří Běhal, Roman Ruzek, Martin Holzleitner, Sascha Senck

Abstract:

In order to reduce fuel consumption and CO₂ emissions in the aviation sector, innovative solutions are being sought to reduce the weight of aircraft, including additive manufacturing (AM). Of particular importance are the excellent mechanical properties that are required for aircraft structures. Ti6Al4V alloys, with their high mechanical properties in relation to weight, can reduce the weight of aircraft structures compared to structures made of steel and aluminium. Currently, conventional processes such as casting and CNC machining are used to obtain the desired structures, resulting in high raw material removal, which in turn leads to higher costs and impacts the environment. Additive manufacturing (AM) offers advantages in terms of weight, lead time, design, and functionality and enables the realisation of alternative geometric shapes with high mechanical properties. However, there are currently technological shortcomings that have led to AM not being approved for structural components with high safety requirements. An assessment of damage tolerance for AM parts is required, and quality control needs to be improved. Pores and other defects cannot be completely avoided at present, but they should be kept to a minimum during manufacture. The mechanical properties of the manufactured parts can be further improved by various treatments. The influence of different treatment methods (heat treatment, CNC milling, electropolishing, chemical polishing) and operating parameters were investigated by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX), X-ray diffraction (XRD), electron backscatter diffraction (EBSD) and measurements with a focused ion beam (FIB), taking into account surface roughness, possible anomalies in the chemical composition of the surface and possible cracks. The results of the characterisation of the constructed and treated samples are discussed and presented in this paper. These results were generated within the framework of the 3TANIUM project, which is financed by EU with the contract number 101007830.

Keywords: Ti6Al4V alloys, laser powder bed fusion, damage tolerance, heat treatment, electropolishing, potential cracking

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1489 On a Determination of Residual Stresses and Wear Resistance of Thermally Sprayed Stainless Steel Coating

Authors: Merzak Laribi, Abdelmadjid Kasser

Abstract:

Thermal spraying processes are widely used to produce coatings on original constructions as well as in repair and maintenance of long standing structures. A lot of efforts forwarding to develop thermal spray coatings technology have been focused on improving mechanical characteristics, minimizing residual stress level and reducing porosity of the coatings. The specific aim of this paper is to determine either residual stresses distribution or wear resistance of stainless steel coating thermally sprayed on a carbon steel substrate. Internal stresses determination was performed using an extensometric method in combination with a simultaneous progressive electrolytic polishing. The procedure consists of measuring micro-deformations using a bi-directional extensometric gauges glued on the substrate side of the materials. Very thin layers of the deposits are removed by electrochemical polishing across the sample surface. Micro-deformations are instantaneously measured, leading to residual stresses calculation after each removal. Wear resistance of the coating has been determined using a ball-on-plate tribometer. Friction coefficient is instantaneously measured during the tribological test. Attention was particularly focused on the influence of a post-annealing at 850 °C for one hour in vacuum either on the residual stresses distribution or on the wear resistance behavior under specific wear and lubrication conditions. The obtained results showed that the microstructure of the obtained arc sprayed stainless steel coating is classical. It is homogeneous and contains un-melted particles, metallic oxides and also pores and micro-cracks. The internal stresses are in compression in the coating. They are more or less scattered between -50 and -270 MPa on the surface and decreased more at the interface. The value at the surface of the substrate is about –700 MPa, partially due to the molten particles impact with the substrate. The post annealing has reduced the residual stresses in both coating and surface of the steel substrate so that the hole material becomes more relaxed. Friction coefficient has an average value of 0.3 and 0.4 respectively for non annealed and annealed specimen. It is rather oil lubrication which is really benefit so that friction coefficient is decreased to about 0.06.

Keywords: residual stresses, wear resistance, stainless steel, coating, thermal spraying, annealing, lubrication

Procedia PDF Downloads 114
1488 The Role of Autophagy Modulation in Angiotensin-II Induced Hypertrophy

Authors: Kitti Szoke, Laszlo Szoke, Attila Czompa, Arpad Tosaki, Istvan Lekli

Abstract:

Autophagy plays an important role in cardiac hypertrophy, which is one of the most common causes of heart failure in the world. This self-degradative catabolic process, responsible for protein quality control, balancing sources of energy at critical times, and elimination of damaged organelles. The autophagic activity can be triggered by starvation, oxidative stress, or pharmacological agents, like rapamycin. This induced autophagy can promote cell survival during starvation or pathological stress. In this study, it is investigated the effect of the induced autophagic process on angiotensin induced hypertrophic H9c2 cells. In our study, it is used H9c2 cells as an in vitro model. To induce hypertrophy, cells were treated with 10000 nM angiotensin-II, and to activate autophagy, 100 nM rapamycin treatment was used. The following groups were formed: 1: control, 2: 10000 nM AT-II, 3: 100 nM rapamycin, 4: 100 nM rapamycin pretreatment then 10000 nM AT-II. The cell viability was examined via MTT (cell proliferation assay) assay. The cells were stained with rhodamine-conjugated phalloidin and DAPI to visualize F-actin filaments and cell nuclei then the cell size alteration was examined in a fluorescence microscope. Furthermore, the expression levels of autophagic and apoptotic proteins such as Beclin-1, p62, LC3B-II, Cleaved Caspase-3 were evaluated by Western blot. MTT assay result suggests that the used pharmaceutical agents in the tested concentrations did not have a toxic effect; however, at group 3, a slight decrement was detected in cell viability. In response to AT-II treatment, a significant increase was detected in the cell size; cells became hypertrophic. However, rapamycin pretreatment slightly reduced the cell size compared to group 2. Western blot results showed that AT-II treatment-induced autophagy, because the increased expression of Beclin-1, p62, LC3B-II were observed. However, due to the incomplete autophagy, the apoptotic Cleaved Caspase-3 expression also increased. Rapamycin pretreatment up-regulated Beclin-1 and LC3B-II, down-regulated p62 and Cleaved Caspase-3, indicating that rapamycin-induced autophagy can restore the normal autophagic flux. Taken together, our results suggest that rapamycin activated autophagy reduces angiotensin-II induced hypertrophy.

Keywords: angiotensin-II, autophagy, H9c2 cell line, hypertrophy, rapamycin

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1487 Gadolinium-Based Polymer Nanostructures as Magnetic Resonance Imaging Contrast Agents

Authors: Franca De Sarno, Alfonso Maria Ponsiglione, Enza Torino

Abstract:

Recent advances in diagnostic imaging technology have significantly contributed to a better understanding of specific changes associated with diseases progression. Among different imaging modalities, Magnetic Resonance Imaging (MRI) represents a noninvasive medical diagnostic technique, which shows low sensitivity and long acquisition time and it can discriminate between healthy and diseased tissues by providing 3D data. In order to improve the enhancement of MRI signals, some imaging exams require intravenous administration of contrast agents (CAs). Recently, emerging research reports a progressive deposition of these drugs, in particular, gadolinium-based contrast agents (GBCAs), in the body many years after multiple MRI scans. These discoveries confirm the need to have a biocompatible system able to boost a clinical relevant Gd-chelate. To this aim, several approaches based on engineered nanostructures have been proposed to overcome the common limitations of conventional CAs, such as the insufficient signal-to-noise ratios due to relaxivity and poor safety profile. In particular, nanocarriers, labeling or loading with CAs, capable of carrying high payloads of CAs have been developed. Currently, there’s no a comprehensive understanding of the thermodynamic contributions enable of boosting the efficacy of conventional CAs by using biopolymers matrix. Thus, considering the importance of MRI in diagnosing diseases, here it is reported a successful example of the next generation of these drugs where the commercial gadolinium chelate is incorporate into a biopolymer nanostructure, formed by cross-linked hyaluronic acid (HA), with improved relaxation properties. In addition, they are highlighted the basic principles ruling biopolymer-CA interactions in the perspective of their influence on the relaxometric properties of the CA by adopting a multidisciplinary experimental approach. On the basis of these discoveries, it is clear that the main point consists in increasing the rigidification of readily-available Gd-CAs within the biopolymer matrix by controlling the water dynamics, the physicochemical interactions, and the polymer conformations. In the end, the acquired knowledge about polymer-CA systems has been applied to develop of Gd-based HA nanoparticles with enhanced relaxometric properties.

Keywords: biopolymers, MRI, nanoparticles, contrast agent

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1486 Suitable Site Selection of Small Dams Using Geo-Spatial Technique: A Case Study of Dadu Tehsil, Sindh

Authors: Zahid Khalil, Saad Ul Haque, Asif Khan

Abstract:

Decision making about identifying suitable sites for any project by considering different parameters is difficult. Using GIS and Multi-Criteria Analysis (MCA) can make it easy for those projects. This technology has proved to be an efficient and adequate in acquiring the desired information. In this study, GIS and MCA were employed to identify the suitable sites for small dams in Dadu Tehsil, Sindh. The GIS software is used to create all the spatial parameters for the analysis. The parameters that derived are slope, drainage density, rainfall, land use / land cover, soil groups, Curve Number (CN) and runoff index with a spatial resolution of 30m. The data used for deriving above layers include 30-meter resolution SRTM DEM, Landsat 8 imagery, and rainfall from National Centre of Environment Prediction (NCEP) and soil data from World Harmonized Soil Data (WHSD). Land use/Land cover map is derived from Landsat 8 using supervised classification. Slope, drainage network and watershed are delineated by terrain processing of DEM. The Soil Conservation Services (SCS) method is implemented to estimate the surface runoff from the rainfall. Prior to this, SCS-CN grid is developed by integrating the soil and land use/land cover raster. These layers with some technical and ecological constraints are assigned weights on the basis of suitability criteria. The pairwise comparison method, also known as Analytical Hierarchy Process (AHP) is taken into account as MCA for assigning weights on each decision element. All the parameters and group of parameters are integrated using weighted overlay in GIS environment to produce suitable sites for the Dams. The resultant layer is then classified into four classes namely, best suitable, suitable, moderate and less suitable. This study reveals a contribution to decision-making about suitable sites analysis for small dams using geospatial data with minimal amount of ground data. This suitability maps can be helpful for water resource management organizations in determination of feasible rainwater harvesting structures (RWH).

Keywords: Remote sensing, GIS, AHP, RWH

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1485 Oral Supplementation of Sweet Orange Extract “Citrus Sinensis” as Substitute for Synthetic Vitamin C on Transported Pullets in Humid Tropics

Authors: Mathew O. Ayoola, Foluke Aderemi, Tunde E. Lawal, Opeyemi Oladejo, Micheal A. Abiola

Abstract:

Food animals reared for meat require transportation during their life cycle. The transportation procedures could initiate stressors capable of disrupting the physiological homeostasis. Such stressors associated with transportation may include; loading and unloading, crowding, environmental temperature, fear, vehicle motion/vibration, feed / water deprivation, and length of travel. This may cause oxidative stress and damage to excess free radicals or reactive oxygen species (ROS). In recent years, the application of natural products as a substitute for synthetic electrolytes and tranquilizers as anti-stress agents during the transportation is yet under investigation. Sweet orange, a predominant fruit in humid tropics, has been reported to have a good content of vitamin C (Ascorbic acid). Vitamin C, which is an active ingredient in orange juice, plays a major role in the biosynthesis of Corticosterone, a hormone that enhances energy supply during transportation and heat stress. Ninety-six, 15weeks, Isa brown pullets were allotted to four (4) oral treatments; sterile water (T1), synthetic vit C (T2), 30ml orange/liter of water (T3), 50ml orange/1 liter (T4). Physiological parameters; body temperature (BTC), rectal temperature (RTC), respiratory rate (RR), and panting rate (PR) were measured pre and post-transportation. The birds were transported with a specialized vehicle for a distance of 50km at a speed of 60 km/hr. The average environmental THI and within the vehicle was 81.8 and 74.6, respectively, and the average wind speed was 11km/hr. Treatments and periods had a significant (p>0.05) effect on all the physiological parameters investigated. Birds on T1 are significantly (p<0.05) different as compared to T2, T3, and T4. Values recorded post-transportation are significantly (p<0.05) higher as compared to pre-transportation for all parameters. In conclusion, this study showed that transportation as a stressor can affect the physiological homeostasis of pullets. Oral supplementation of electrolytes or tranquilizers is essential as an anti-stress during transportation. The application of the organic product in form of sweet orange could serve as a suitable alternative for the synthetic vitamin C.

Keywords: physiological, pullets, sweet orange, transportation stress, and vitamin C

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1484 A Traditional Settlement in a Modernized City: Yanbu, Saudi Arabia

Authors: Hisham Mortada

Abstract:

Transition in the urban configuration of Arab cities has never been as radical and visible as it has been since the turn of the last century. The emergence of new cities near historical settlements of Arabia has spawned a series of developments in and around the old city precincts. New developments are based on advanced technology and conform to globally prevalent standards of city planning, superseding the vernacular arrangements based on traditional norms that guided so-called ‘city planning’. Evidence to this fact are the extant Arab buildings present at the urban core of modern cities, which inform us about intricate spatial organization. Organization that subscribed to multiple norms such as, satisfying gender segregation and socialization, economic sustainability, and ensuring security and environmental coherence etc., within settlement compounds. Several participating factors achieved harmony in such an inclusive city—an organization that was challenged and apparently replaced by the new planning order in the face of growing needs of globalized, economy-centric and high-tech models of development. Communities found it difficult to acclimatize with the new western planning models that were implemented at a very large scale throughout the Kingdom, which later experienced spatial re-structuring to suit users’ needs. A closer look the ancient city of Yanbu, now flanked with such new developments, allows us to differentiate and track the beginnings of this unprecedented transition in settlement formations. This paper aims to elaborate the Arabian context offered to both the ‘traditional’ and ‘modern’ planning approaches, in order to understand challenges and solutions offered by both at different times. In the process it will also establish the inconsistencies and conflicts that arose with the shift in planning paradigm, from traditional-'cultural norms’, to modern-'physical planning', in the Arabian context. Thus, by distinguishing the two divergent planning philosophies, their impact of the Arabian morphology, relevance to lifestyle and suitability to the biophysical environment, it concludes with a perspective on sustainability particularly for in case of Yanbu.

Keywords: Yanbu, traditional architecture, Hijaz, coral building, Saudi Arabia

Procedia PDF Downloads 298