Search results for: collapse capacity
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4476

Search results for: collapse capacity

4086 Breath Ethanol Imaging System Using Real Time Biochemical Luminescence for Evaluation of Alcohol Metabolic Capacity

Authors: Xin Wang, Munkbayar Munkhjargal, Kumiko Miyajima, Takahiro Arakawa, Kohji Mitsubayashi

Abstract:

The measurement of gaseous ethanol plays an important role of evaluation of alcohol metabolic capacity in clinical and forensic analysis. A 2-dimensional visualization system for gaseous ethanol was constructed and tested in visualization of breath and transdermal alcohol. We demonstrated breath ethanol measurement using developed high-sensitive visualization system. The concentration of breath ethanol calculated with the imaging signal was significantly different between the volunteer subjects of ALDH2 (+) and (-).

Keywords: breath ethanol, ethnaol imaging, biochemical luminescence, alcohol metabolism

Procedia PDF Downloads 351
4085 Experimental Study on Weak Cohesion Less Soil Using Granular Piles with Geogrid Reinforcement

Authors: Sateesh Kumar Pisini, Swetha Priya Pisini

Abstract:

Granular piles are becoming popular as a technique of deep ground improvement not only in soft cohesive soils but also in loose cohesionless deposits. The present experimental study has been carried out on granular piles in sand (loose sand and medium dense sand i.e. relative density at 15% and 30%) with geogrid reinforcement. In this experimental study, a group of five piles installed in sand (at different spacing i.e s = 2d, 3d and 4d) the length and diameter of the pile (L = 0.4 m and d= 50 mm) kept as same for all series of experiments. Geogrid reinforcement is provided on granular piles with a limited number of laboratory tests. It has been conducted in laboratory to study the behavior of a granular pile with reinforced geogrid layers supporting a square footing at different s/d ratios. The influence of geogrid layers providing on granular piles investigated through model tests. In this paper the experimental study carried out results in significant increase in load carrying capacity and decrease in settlement reduction of the weak cohesionless soil. Also, the behavior of load carrying capacity and settlement with changing the s/d ratio has been carried out through a parametric study.

Keywords: granular piles, cohesionless soil, geogrid reinforcement, load carrying capacity

Procedia PDF Downloads 261
4084 Circular Raft Footings Strengthened by Stone Columns under Static Loads

Authors: R. Ziaie Moayed, B. Mohammadi-Haji

Abstract:

Stone columns have been widely employed to improve the load-settlement characteristics of soft soils. The results of two small scale displacement control loading tests on stone columns were used in order to validate numerical finite element simulations. Additionally, a series of numerical calculations of static loading have been performed on strengthened raft footing to investigate the effects of using stone columns on bearing capacity of footings. The bearing capacity of single and group of stone columns under static loading compares with unimproved ground.

Keywords: circular raft footing, numerical analysis, validation, vertically encased stone column

Procedia PDF Downloads 311
4083 Design of Black-Seed Pulp biomass-Derived New Bio-Sorbent by Combining Methods of Mineral Acids and High-Temperature for Arsenic Removal

Authors: Mozhgan Mohammadi, Arezoo Ghadi

Abstract:

Arsenic is known as a potential threat to the environment. Therefore, the aim of this research is to assess the arsenic removal efficiency from an aqueous solution, with a new biosorbent composed of a black seed pulp (BSP). To treat BSP, the combination of two methods (i.e. treating with mineral acids and use at high temperature) was used and designed bio-sorbent called BSP-activated/carbonized. The BSP-activated and BSP-carbonized were also prepared using HCL and 400°C temperature, respectively, to compare the results of each three methods. Followed by, adsorption parameters such as pH, initial ion concentration, biosorbent dosage, contact time, and temperature were assessed. It was found that the combination method has provided higher adsorption capacity so that up to ~99% arsenic removal was observed with BSP-activated/carbonized at pH of 7.0 and 40°C. The adsorption capacity for BSP-carbonized and BSP-activated were 87.92% (pH: 7, 60°C) and 78.50% (pH: 6, 90°C), respectively. Moreover, adsorption kinetics data indicated the best fit with the pseudo-second-order model. The maximum biosorption capacity, by the Langmuir isotherm model, was also recorded for BSP-activated/carbonized (53.47 mg/g). It is notable that arsenic adsorption on studied bio sorbents takes place as spontaneous and through chemisorption along with the endothermic nature of the biosorption process and reduction of random collision in the solid-liquid phase.

Keywords: black seed pulp, bio-sorbents, treatment of sorbents, adsorption isotherms

Procedia PDF Downloads 95
4082 Activated Carbons Prepared from Date Pits for Hydrogen Storage

Authors: M. Belhachemi, M. Monteiro de Castro, M. Casco, A. Sepúlveda-Escribano, F. Rodríguez-Reinoso

Abstract:

In this study, activated carbons were prepared from Algerian date pits using thermal activation with CO2 or steam. The prepared activated carbons were doped by vanadium oxide in order to increase the H2 adsorption capacity. The adsorbents were characterized by N2 and CO2 adsorption at 77 K and 273K, respectively. The hydrogen adsorption experiments were carried at 298K in the 0–100 bar pressure range using a volumetric equipment. The results show that the H2 adsorption capacity is influenced by the size and volume of micropores in the activated carbon adsorbent. Furthermore, vanadium doping of activated carbons has a slight positive effect on H2 storage.

Keywords: hydrogen storage, activated carbon, vanadium doping, adsorption

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4081 [Keynote Talk]: Unlocking Transformational Resilience in the Aftermath of a Flood Disaster: A Case Study from Cumbria

Authors: Kate Crinion, Martin Haran, Stanley McGreal, David McIlhatton

Abstract:

Past research has demonstrated that disasters are continuing to escalate in frequency and magnitude worldwide, representing a key concern for the global community. Understanding and responding to the increasing risk posed by disaster events has become a key concern for disaster managers. An emerging trend within literature, acknowledges the need to move beyond a state of coping and reinstatement of the status quo, towards incremental adaptive change and transformational actions for long-term sustainable development. As such, a growing interest in research concerns the understanding of the change required to address ever increasing and unpredictable disaster events. Capturing transformational capacity and resilience, however is not without its difficulties and explains the dearth in attempts to capture this capacity. Adopting a case study approach, this research seeks to enhance an awareness of transformational resilience by identifying key components and indicators that determine the resilience of flood-affected communities within Cumbria. Grounding and testing a theoretical resilience framework within the case studies, permits the identification of how perceptions of risk influence community resilience actions. Further, it assesses how levels of social capital and connectedness impacts upon the extent of interplay between resources and capacities that drive transformational resilience. Thus, this research seeks to expand the existing body of knowledge by enhancing the awareness of resilience in post-disaster affected communities, by investigating indicators of community capacity building and resilience actions that facilitate transformational resilience during the recovery and reconstruction phase of a flood disaster.

Keywords: capacity building, community, flooding, transformational resilience

Procedia PDF Downloads 289
4080 Valorization of a Forest Waste, Modified P-Brutia Cones, by Biosorption of Methyl Geen

Authors: Derradji Chebli, Abdallah Bouguettoucha, Abdelbaki Reffas Khalil Guediri, Abdeltif Amrane

Abstract:

The removal of Methyl Green dye (MG) from aqueous solutions using modified P-brutia cones (PBH and PBN), has been investigated work. The physical parameters such as pH, temperature, initial MG concentration, ionic strength are examined in batch experiments on the sorption of the dye. Adsorption removal of MG was conducted at natural pH 4.5 because the dye is only stable in the range of pH 3.8 to 5. It was observed in experiments that the P-brutia cones treated with NaOH (PBN) exhibited high affinity and adsorption capacity compared to the MG P-brutia cones treated with HCl (PBH) and biosorption capacity of modified P-brutia cones (PBN and PBH) was enhanced by increasing the temperature. This is confirmed by the thermodynamic parameters (ΔG° and ΔH°) which show that the adsorption of MG was spontaneous and endothermic in nature. The positive values of ΔS° suggested an irregular increase in the randomness for both adsorbent (PBN and PBH) during the adsorption process. The kinetic model pseudo-first order, pseudo-second order, and intraparticle diffusion coefficient were examined to analyze the sorption process; they showed that the pseudo-second-order model is the one that best describes the adsorption process (MG) on PBN and PBH with a correlation coefficient R²> 0.999. The ionic strength has shown that it has a negative impact on the adsorption of MG on two supports. A reduction of 68.5% of the adsorption capacity for a value Ce=30 mg/L was found for the PBH, while the PBN did not show a significant influence of the ionic strength on adsorption especially in the presence of NaCl. Among the tested isotherm models, the Langmuir isotherm was found to be the most relevant to describe MG sorption onto modified P-brutia cones with a correlation factor R²>0.999. The capacity adsorption of P-brutia cones, was confirmed for the removal of a dye, MG, from aqueous solution. We note also that P-brutia cones is a material very available in the forest and low-cost biomaterial

Keywords: adsorption, p-brutia cones, forest wastes, dyes, isotherm

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4079 Development of Sb/MWCNT Free Standing Anode for Li-Ion Batteries

Authors: Indu Elizabeth

Abstract:

Antimony/Multi Walled Carbon nano tube nanocomposite (Sb/MWCNT) is synthesized using ethylene glycol mediated reduction process. Binder free, self-supporting and flexible Sb/MWCNT nanocomposite paper has been prepared by employing the vacuum filtration technique. The samples are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy (RS), and thermal gravimetric analysis (TGA) to evaluate the structure of anode and tested for its performance in a Lithium rechargeable cell. Electrochemical measurements demonstrate that the Sb/MWCNT composite paper anode delivers a specific discharge capacity of ~400 mAh g-1 up to a current density of 100 mA g-1.

Keywords: antimony, lithium ion battery, multiwalled carbon nanotube, specific capacity

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4078 A Controlled Mathematical Model for Population Dynamics in an Infested Honeybees Colonies

Authors: Chakib Jerry, Mounir Jerry

Abstract:

In this paper, a mathematical model of infested honey bees colonies is formulated in order to investigate Colony Collapse Disorder in a honeybee colony. CCD, as it is known, is a major problem on honeybee farms because of the massive decline in colony numbers. We introduce to the model a control variable which represents forager protection. We study the controlled model to derive conditions under which the bee colony can fight off epidemic. Secondly we study the problem of minimizing prevention cost under model’s dynamics constraints.

Keywords: honey bee, disease transmission model, disease control honeybees, optimal control

Procedia PDF Downloads 426
4077 Evaluation of Expected Annual Loss Probabilities of RC Moment Resisting Frames

Authors: Saemee Jun, Dong-Hyeon Shin, Tae-Sang Ahn, Hyung-Joon Kim

Abstract:

Building loss estimation methodologies which have been advanced considerably in recent decades are usually used to estimate socio and economic impacts resulting from seismic structural damage. In accordance with these methods, this paper presents the evaluation of an annual loss probability of a reinforced concrete moment resisting frame designed according to Korean Building Code. The annual loss probability is defined by (1) a fragility curve obtained from a capacity spectrum method which is similar to a method adopted from HAZUS, and (2) a seismic hazard curve derived from annual frequencies of exceedance per peak ground acceleration. Seismic fragilities are computed to calculate the annual loss probability of a certain structure using functions depending on structural capacity, seismic demand, structural response and the probability of exceeding damage state thresholds. This study carried out a nonlinear static analysis to obtain the capacity of a RC moment resisting frame selected as a prototype building. The analysis results show that the probability of being extensive structural damage in the prototype building is expected to 0.004% in a year.

Keywords: expected annual loss, loss estimation, RC structure, fragility analysis

Procedia PDF Downloads 398
4076 Probabilistic Model for Evaluating Seismic Soil Liquefaction Based on Energy Approach

Authors: Hamid Rostami, Ali Fallah Yeznabad, Mohammad H. Baziar

Abstract:

The energy-based method for evaluating seismic soil liquefaction has two main sections. First is the demand energy, which is dissipated energy of earthquake at a site, and second is the capacity energy as a representation of soil resistance against liquefaction hazard. In this study, using a statistical analysis of recorded data by 14 down-hole array sites in California, an empirical equation was developed to estimate the demand energy at sites. Because determination of capacity energy at a site needs to calculate several site calibration factors, which are obtained by experimental tests, in this study the standard penetration test (SPT) N-value was assumed as an alternative to the capacity energy at a site. Based on this assumption, the empirical equation was employed to calculate the demand energy for 193 liquefied and no-liquefied sites and then these amounts were plotted versus the corresponding SPT numbers for all sites. Subsequently, a discrimination analysis was employed to determine the equations of several boundary curves for various liquefaction likelihoods. Finally, a comparison was made between the probabilistic model and the commonly used stress method. As a conclusion, the results clearly showed that energy-based method can be more reliable than conventional stress-based method in evaluation of liquefaction occurrence.

Keywords: energy demand, liquefaction, probabilistic analysis, SPT number

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4075 Investigation the Effect of Nano-Alumina Particles on Physical Adsorption Property of Acrylic Fiber

Authors: Mehdi Ketabchi, Shamsollah Alijanlou

Abstract:

The flue gas from fossil fuels combustion contains harmful pollutants dangerous for human health and the environment. One of the air pollution control methods to restrict the emission of these pollutants is based on using the nanoparticle in the adsorption process. In the present research gamma, Nano-alumina particle is added to Polyacrylonitrile (PAN) polymer through simple loading method and the adsorption capacity of the wet spun fiber is investigated. The results of exposure the fiber to the acid gasses including SO2, CO, NO2, NO and CO2 show the noticeable increase of gas adsorption capacity on fiber contains nanoparticle. The research has been conducted in Acrylic II Plant of Polyacryl Iran Corporation.

Keywords: acrylic fiber, adsorbent, wet spun, nano gamma alumina

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4074 Usage of Cyanobacteria in Battery: Saving Money, Enhancing the Storage Capacity, Making Portable, and Supporting the Ecology

Authors: Saddam Husain Dhobi, Bikrant Karki

Abstract:

The main objective of this paper is save money, balance ecosystem of the terrestrial organism, control global warming, and enhancing the storage capacity of the battery with requiring weight and thinness by using Cyanobacteria in the battery. To fulfill this purpose of paper we can use different methods: Analysis, Biological, Chemistry, theoretical and Physics with some engineering design. Using this different method, we can produce the special type of battery that has the long life, high storage capacity, and clean environment, save money so on and by using the byproduct of Cyanobacteria i.e. glucose. Cyanobacteria are a special type of bacteria that produces different types of extracellular glucoses and oxygen with the help of little sunlight, water, and carbon dioxide and can survive in freshwater, marine and in the land as well. In this process, O₂ is more in the comparison to plant due to rapid growth rate of Cyanobacteria. The required materials are easily available in this process to produce glucose with the help of Cyanobacteria. Since CO₂, is greenhouse gas that causes the global warming? We can utilize this gas and save our ecological balance and the byproduct (glucose) C₆H₁₂O₆ can be utilized for raw material for the battery where as O₂ escape is utilized by living organism. The glucose produce by Cyanobateria goes on Krebs's Cycle or Citric Acid Cycle, in which glucose is complete, oxidizes and all the available energy from glucose molecule has been release in the form of electron and proton as energy. If we use a suitable anodes and cathodes, we can capture these electrons and protons to produce require electricity current with the help of byproduct of Cyanobacteria. According to "Virginia Tech Bio-battery" and "Sony" 13 enzymes and the air is used to produce nearly 24 electrons from a single glucose unit. In this output power of 0.8 mW/cm, current density of 6 mA/cm, and energy storage density of 596 Ah/kg. This last figure is impressive, at roughly 10 times the energy density of the lithium-ion batteries in your mobile devices. When we use Cyanobacteria in battery, we are able to reduce Carbon dioxide, Stop global warming, and enhancing the storage capacity of battery more than 10 times that of lithium battery, saving money, balancing ecology. In this way, we can produce energy from the Cyanobacteria and use it in battery for different benefits. In addition, due to the mass, size and easy cultivation, they are better to maintain the size of battery. Hence, we can use Cyanobacteria for the battery having suitable size, enhancing the storing capacity of battery, helping the environment, portability and so on.

Keywords: anode, byproduct, cathode, cyanobacteri, glucose, storage capacity

Procedia PDF Downloads 349
4073 A Review on Concrete Structures in Fire

Authors: S. Iffat, B. Bose

Abstract:

Concrete as a construction material is versatile because it displays high degree of fire-resistance. Concrete’s inherent ability to combat one of the most devastating disaster that a structure can endure in its lifetime, can be attributed to its constituent materials which make it inert and have relatively poor thermal conductivity. However, concrete structures must be designed for fire effects. Structural components should be able to withstand dead and live loads without undergoing collapse. The properties of high-strength concrete must be weighed against concerns about its fire resistance and susceptibility to spalling at elevated temperatures. In this paper, the causes, effects and some remedy of deterioration in concrete due to fire hazard will be discussed. Some cost effective solutions to produce a fire resistant concrete will be conversed through this paper.

Keywords: concrete, fire, spalling, temperature, compressive strength, density

Procedia PDF Downloads 443
4072 Evaluation on Heat and Drought Tolerance Capacity of Chickpea

Authors: Derya Yucel, Nigar Angın, Dürdane Mart, Meltem Turkeri, Volkan Catalkaya, Celal Yucel

Abstract:

Chickpea (Cicer arietinum L.) is one of the important legumes widely grown for dietery proteins in semi-arid Mediteranean climatic conditions. To evaluate the genetic diversity with improved heat and drought tolerance capacity in chickpea, thirty-four selected chickpea genotypes were tested under different field-growing conditions (rainfed winter sowing, irrigated-late sowing and rainfed-late sowing) in 2015 growing season. A factorial experiment in randomized complete block design with 3 reps was conducted at the Eastern Mediterranean Research Institute Adana, Turkey. Based on grain yields under different growing conditions, several indices were calculated to identify economically higher-yielding chickpea genotypes with greater heat and drought tolerance capacity. Average across chickpea genotypes, the values of tolerance index, mean productivity, yield index, yield stability index, stress tolerance index, stress susceptibility index, and geometric mean productivity were ranged between 1.1 to 218, 38 to 202, 0.3 to 1.7, 0.2 to 1, 0.1 to 1.2, 0.02 to 1.4, and 36 to 170 for drought stress and 3 to 54, 23 to 118, 0.3 to 1.7, 0.4 to 0.9, 0.2 to 2, 0.2to 2.3, and 23 to 118 for heat stress, respectively. There were highly significant differences observed among the tested chickpea genotypes response to drought and heat stresses. Among the chickpea genotypes, the Aksu, Arda, Çakır, F4 09 (X 05 TH 21-16189), FLIP 03-108 were identified with a higher drought and heat tolerance capacity. Based on our field studies, it is suggested that the drought and heat tolerance indicators of plants can be used by breeders to select stress-resistant economically productive chickpea genotypes suitable to grow under Mediteranean climatic conditions.

Keywords: irrigation, rainfed, stress susceptibility, tolerance indice

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4071 The Influence of Microcapsulated Phase Change Materials on Thermal Performance of Geopolymer Concrete

Authors: Vinh Duy Cao, Shima Pilehvar, Anna M. Szczotok, Anna-Lena Kjøniksen

Abstract:

The total energy consumption is dramatically increasing on over the world, especially for building energy consumption where a significant proportion of energy is used for heating and cooling purposes. One of the solutions to reduce the energy consumption for the building is to improve construction techniques and enhance material technology. Recently, microcapsulated phase change materials (MPCM) with high energy storage capacity within the phase transition temperature of the materials is a potential method to conserve and save energy. A new composite materials with high energy storage capacity by mixing MPCM into concrete for passive building technology is the promising candidate to reduce the energy consumption. One of the most untilized building materials for mixing with MPCM is Portland cement concrete. However, the emission of carbon dioxide (CO2) due to producing cement which plays the important role in the global warming is the main drawback of PCC. Accordingly, an environmentally friendly building material, geopolymer, which is synthesized by the reaction between the industrial waste material (aluminosilicate) and a strong alkali activator, is a potential materials to mixing with MPCM. Especially, the effect of MPCM on the thermal and mechanical properties of geopolymer concrete (GPC) is very limited. In this study, high thermal energy storage capacity materials were fabricated by mixing MPCM into geopolymer concrete. This article would investigate the effect of MPCM concentration on thermal and mechanical properties of GPC. The target is to balance the effect of MPCM on improving the thermal performance and maintaining the compressive strength of the geopolymer concrete at an acceptable level for building application.

Keywords: microencapsulated phase change materials, geopolymer concrete, energy storage capacity, thermal performance

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4070 Study on Bending Characteristics of Square Tube Using Energy Absorption Part

Authors: Shigeyuki Haruyama, Zefry Darmawan, Ken Kaminishi

Abstract:

In the square tube subjected to the bending load, the rigidity of the entire square tube is reduced when a collapse occurs due to local stress concentration. Therefore, in this research, the influence of bending load on the square tube with attached energy absorbing part was examined and reported. The analysis was conducted by using Finite Element Method (FEM) to produced bending deflection and buckling points. Energy absorption was compared from rigidity of attached part and square tube body. Buckling point was influenced by the rigidity of attached part and the thickness rate of square tube.

Keywords: energy absorber, square tube, bending, rigidity

Procedia PDF Downloads 244
4069 Spatial Analysis in the Impact of Aquifer Capacity Reduction on Land Subsidence Rate in Semarang City between 2014-2017

Authors: Yudo Prasetyo, Hana Sugiastu Firdaus, Diyanah Diyanah

Abstract:

The phenomenon of the lack of clean water supply in several big cities in Indonesia is a major problem in the development of urban areas. Moreover, in the city of Semarang, the population density and growth of physical development is very high. Continuous and large amounts of underground water (aquifer) exposure can result in a drastically aquifer supply declining in year by year. Especially, the intensity of aquifer use in the fulfilment of household needs and industrial activities. This is worsening by the land subsidence phenomenon in some areas in the Semarang city. Therefore, special research is needed to know the spatial correlation of the impact of decreasing aquifer capacity on the land subsidence phenomenon. This is necessary to give approve that the occurrence of land subsidence can be caused by loss of balance of pressure on below the land surface. One method to observe the correlation pattern between the two phenomena is the application of remote sensing technology based on radar and optical satellites. Implementation of Differential Interferometric Synthetic Aperture Radar (DINSAR) or Small Baseline Area Subset (SBAS) method in SENTINEL-1A satellite image acquisition in 2014-2017 period will give a proper pattern of land subsidence. These results will be spatially correlated with the aquifer-declining pattern in the same time period. Utilization of survey results to 8 monitoring wells with depth in above 100 m to observe the multi-temporal pattern of aquifer change capacity. In addition, the pattern of aquifer capacity will be validated with 2 underground water cavity maps from observation of ministries of energy and natural resources (ESDM) in Semarang city. Spatial correlation studies will be conducted on the pattern of land subsidence and aquifer capacity using overlapping and statistical methods. The results of this correlation will show how big the correlation of decrease in underground water capacity in influencing the distribution and intensity of land subsidence in Semarang city. In addition, the results of this study will also be analyzed based on geological aspects related to hydrogeological parameters, soil types, aquifer species and geological structures. The results of this study will be a correlation map of the aquifer capacity on the decrease in the face of the land in the city of Semarang within the period 2014-2017. So hopefully the results can help the authorities in spatial planning and the city of Semarang in the future.

Keywords: aquifer, differential interferometric synthetic aperture radar (DINSAR), land subsidence, small baseline area subset (SBAS)

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4068 Pedagogical Agency: A Basic Capacity to Carry out a Humanizing and Democratic Pedagog

Authors: Priscilla Echeverria

Abstract:

For us grown up in neoliberal societies, it is not always clear that we have not only incorporated an economic logic into our subjectivities, but a technical reason, an instrumental way of relationship with the environment inspired in a control interest that constantly dehumanizes us as takes away our capacity of action, becoming mere objects or bureaucrats, stripped of our citizen dimension to participate in social and political issues responsibly and creatively. To restore the capacity of action -agency- is urgent in our societies to strengthen better democracies. On this, the formal educational system plays a crucial role, which in turn needs teachers prepared to understand their role as integral educators instead of mere curriculum managers. For this reason, initial teacher formation (ITF) programs must assume the responsibility of helping them to develop an ethical/political/epistemic pedagogical agency to deal with a technical school culture and, in turn, able to relate to their students in democratic ways to help them to develop their agency capacities. By highlighting a perspective of education as the opposite of technocracy and bureaucracy, this talk precisely addresses ITF as a crucial and formative space to restore a perspective of what a critical education can look like, enabling pedagogy students with pedagogical agency capacities to, in turn, allow their future students to develop it. This discussion is part of my doctoral research, "The importance of developing the capacity for ethical-political-epistemic agency in novice teachers during initial teacher formation to contribute to social justice", which I currently develop in the Educational Research program of the University of Lancaster, United Kingdom, as a Conicyt fellow for the 2019 cohort. This presentation specifically offers preliminary results of the analysis of critical incidents as a research methodological tool to analyse the capacity of pedagogical agency deployed by novice teachers in their first pedagogical experiences in the Chilean context.

Keywords: initial teacher formation, pedagogical agency, pedagogical interaction, hidden curriculum, critical pedagogy, social justice

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4067 Enhancement of Capacity in a MC-CDMA based Cognitive Radio Network Using Non-Cooperative Game Model

Authors: Kalyani Kulkarni, Bharat Chaudhari

Abstract:

This paper addresses the issue of resource allocation in the emerging cognitive technology. Focusing the quality of service (QoS) of primary users (PU), a novel method is proposed for the resource allocation of secondary users (SU). In this paper, we propose the unique utility function in the game theoretic model of Cognitive Radio which can be maximized to increase the capacity of the cognitive radio network (CRN) and to minimize the interference scenario. The utility function is formulated to cater the need of PUs by observing Signal to Noise ratio. The existence of Nash equilibrium is for the postulated game is established.

Keywords: cognitive networks, game theory, Nash equilibrium, resource allocation

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4066 GC-MS Identification of Two Major Essential Oils and their Anti-Oxidative Effect Using DPPH Assay

Authors: Mohammed Falalu Hamza

Abstract:

A phytochemical investigation conducted on the leaves extract of Cryptocarya latifolia (Lauraceae) revealed the presence of two major essential oils; Nerolidol (1) and Copaene (2) with the aid of gas chromatography-mass spectrometry (GC-MS). The compounds exhibited good anti-oxidant capacity using 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging assay. The result shows that the anti-oxidant capacity of the compounds is dependent on concentration similar to the standard (ascorbic acid). This study shows that the leaves extract of C. latifolia is a good source of important natural antioxidants.

Keywords: broad-leaved quince, phytochemical, anti-oxidant, essential oils

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4065 A Study of Anthraquinone Dye Removal by Using Chitosan Nanoparticles

Authors: Pyar S. Jassal, Sonal Gupta, Neema Chand, Rajni Johar

Abstract:

In present study, Low molecular weight chitosan naoparticles (LMWCNP) were synthesized by using low molecular weight chitosan (LMWC) and sodium tripolyphosphate for the adsorption of anthraquinone dyes from waste water. The ionic-gel technique was used for this purpose. Size of nanoparticles was determined by “Scherrer equation”. The absorbance was carried out with UV-visible spectrophotometer for Acid Green 25 (AG25) and Reactive Blue 4 (RB4) dyes solutions at λmax 644 and λmax 598 nm respectively. The removal of dyes was dependent on the pH and the optimum adsorption was between pH 2 to 9. The extraction of dyes was linearly dependent on temperature. The equilibrium parameters, RL was calculated by using the Langmuir isotherm and shows that adsorption of dyes is favorable on the LMWCNP. The XRD images of LMWC show a crystalline nature whereas LMWCNP is amorphous one. The thermo gravimetric analysis (TGA) shows that LMWCNP thermally more stable than LMWC. As the contact time increases, percentage removal of Acid Green 25 and Reactive Blue 4 dyes also increases. TEM images reveal the size of the LMWCNP were in the range of 45-50 nm. The capacity of AG25 dye on LMWC was 5.23 mg/g, it compared with LMWCNP capacity which was 6.83 mg/g respectively. The capacity of RB4 dye on LMWC was 2.30 mg/g and 2.34 mg/g was on LMWCNP.

Keywords: low molecular weight chitosan nanoparticles, anthraquinone dye, removal efficiency, adsorption isotherm

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4064 Thermodynamic Analysis of Surface Seawater under Ocean Warming: An Integrated Approach Combining Experimental Measurements, Theoretical Modeling, Machine Learning Techniques, and Molecular Dynamics Simulation for Climate Change Assessment

Authors: Nishaben Desai Dholakiya, Anirban Roy, Ranjan Dey

Abstract:

Understanding ocean thermodynamics has become increasingly critical as Earth's oceans serve as the primary planetary heat regulator, absorbing approximately 93% of excess heat energy from anthropogenic greenhouse gas emissions. This investigation presents a comprehensive analysis of Arabian Sea surface seawater thermodynamics, focusing specifically on heat capacity (Cp) and thermal expansion coefficient (α) - parameters fundamental to global heat distribution patterns. Through high-precision experimental measurements of ultrasonic velocity and density across varying temperature (293.15-318.15K) and salinity (0.5-35 ppt) conditions, it characterize critical thermophysical parameters including specific heat capacity, thermal expansion, and isobaric and isothermal compressibility coefficients in natural seawater systems. The study employs advanced machine learning frameworks - Random Forest, Gradient Booster, Stacked Ensemble Machine Learning (SEML), and AdaBoost - with SEML achieving exceptional accuracy (R² > 0.99) in heat capacity predictions. the findings reveal significant temperature-dependent molecular restructuring: enhanced thermal energy disrupts hydrogen-bonded networks and ion-water interactions, manifesting as decreased heat capacity with increasing temperature (negative ∂Cp/∂T). This mechanism creates a positive feedback loop where reduced heat absorption capacity potentially accelerates oceanic warming cycles. These quantitative insights into seawater thermodynamics provide crucial parametric inputs for climate models and evidence-based environmental policy formulation, particularly addressing the critical knowledge gap in thermal expansion behavior of seawater under varying temperature-salinity conditions.

Keywords: climate change, arabian sea, thermodynamics, machine learning

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4063 Human Insecurity and Migration in the Horn of Africa: Causes and Decision Processes

Authors: Belachew Gebrewold

Abstract:

The Horn of Africa is marred by complex and systematic internal and external political, economic and social-cultural causes of conflict that result in internal displacement and migration. This paper engages with them and shows how such a study can help us to understand migration, both in this region and more generally. The conflict has occurred within states, between states, among proxies, between armies. Human insecurities as a result of the state collapse of Somalia, the rise of Islamic fundamentalism in the whole region, recurrent drought affecting the livelihoods of subsistence farmers as well as nomads, exposure to hunger, environmental degradation, youth unemployment, rapid growth of slums around big cities, and political repression (especially in Eritrea) have been driving various segments of the regional population into regional and international migration. Eritrea has been going through a brutal dictatorship which pushes many Eritreans to flee their country and be exposed to human trafficking, torture, detention, and agony on their way to Europe mainly through Egypt, Libya and Israel. Similarly, Somalia has been devastated since 1991 by unending civil war, state collapse, and radical Islamists. There are some important aspects to highlight in the conflict-migration nexus in the Horn of Africa: first, the main push factor for the Somalis and Eritreans to leave their countries and risk their lives is the physical insecurity they have been facing in their countries. Secondly, as a result of the conflict the economic infrastructure is massively destroyed. Investment is rare; job opportunities are out of sight. Thirdly, in such a grim situation the politically and economically induced decision to migrate is a household decision, not only an individual decision. Based on this third point this research study took place in the Horn of Africa between 2014 and 2016 during different occasions. The main objective of the research was to understanding how the increasing migration is affecting the socio-economic and socio-political environment, and conversely how the socio-economic and socio-political environments are increasing migration decisions; and whether and how these decisions are individual or family decisions. The main finding is the higher the human insecurity, the higher the family decision; the lower the human insecurity, the higher the individual decision. These findings apply not only to the Eritrean, Somali migrants but also to Ethiopian migrants. But the general impacts of migration on sending countries’ human security is quite mixed and complex.

Keywords: Eritrea, Ethiopia, Horn of Africa, insecurity, migration, Somalia

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4062 Solar Power Monitoring and Control System using Internet of Things

Authors: Oladapo Tolulope Ibitoye

Abstract:

It has become imperative to harmonize energy poverty alleviation and carbon footprint reduction. This is geared towards embracing independent power generation at local levels to reduce the popular ambiguity in the transmission of generated power. Also, it will contribute towards the total adoption of electric vehicles and direct current (DC) appliances that are currently flooding the global market. Solar power system is gaining momentum as it is now an affordable and less complex alternative to fossil fuel-based power generation. Although, there are many issues associated with solar power system, which resulted in deprivation of optimum working capacity. One of the key problems is inadequate monitoring of the energy pool from solar irradiance, which can then serve as a foundation for informed energy usage decisions and appropriate solar system control for effective energy pooling. The proposed technique utilized Internet of Things (IoT) in developing a system to automate solar irradiance pooling by controlling solar photovoltaic panels autonomously for optimal usage. The technique is potent with better solar irradiance exposure which results into 30% voltage pooling capacity than a system with static solar panels. The evaluation of the system show that the developed system possesses higher voltage pooling capacity than a system of static positioning of solar panel.

Keywords: solar system, internet of things, renewable energy, power monitoring

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4061 The Capacity of Bolted and Screw Connections in Cold-Formed Steel Truss Structure through Analytical and Experimental Method

Authors: Slamet Setioboro, Rahutami Kusumaningsih, Prabowo Setiyawan, Danna Darmayadi

Abstract:

Designing of cold-formed steel capacity connections often based on the formula used for hot rolled steel. It makes the result of the actual capacity connection doesn’t accurate anymore. When the hot rolled steel receives the axial load pull, it will have different characteristics. As the result, there will be failure result when designing Truss structure made of hot rolled steel. This research aims to determine the capacity of actual cold-formed steel connections section which is loaded by the axial tensile force. It will test the appeal of the connection using bolt grafting tool and screw grafting tool. The variations of the test will be on the type of connection (single and double slap), the number of the connection tools and connection configuration. Bold and screw connections failure mode observed in this research are different each other. Failure mode of bolted connections includes sliding pivot plate, tearing at the plate and cutting of the bolt head. While the failure mode of screw connections includes tilting, hole-bearing, pull over and cutting the screw body out. This research was conducted using a laboratory test of HW2-600S Universal Testing Machine model with ASTM E8. It has done in the materials testing laboratory of Mechanical Engineering Department, Faculty of Engineering UNNES. The results obtained through the laboratory diversification towards theoretical calculations using the standards specified in ISO 7971-2013 Cold-Rolled Steel Structures. Based on the research, it can be concluded that the effective connection in receiving force strength is bolted connections neither single nor double plate. The method used is by applying 4 bolts through 2 parallel lines configuration. Furthermore, this connection deals with the consequences of holding the highest Pmaks, lowest failure risk and getting a little kind of mode of failure.

Keywords: axial load, cold-formed steel, capacity connections, bolted connections, screw connections

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4060 Experimental Study on the Heating Characteristics of Transcritical CO₂ Heat Pumps

Authors: Lingxiao Yang, Xin Wang, Bo Xu, Zhenqian Chen

Abstract:

Due to its outstanding environmental performance, higher heating temperature and excellent low-temperature performance, transcritical carbon dioxide (CO₂) heat pumps are receiving more and more attention. However, improperly set operating parameters have a serious negative impact on the performance of the transcritical CO₂ heat pump due to the properties of CO₂. In this study, the heat transfer characteristics of the gas cooler are studied based on the modified “three-stage” gas cooler, then the effect of three operating parameters, compressor speed, gas cooler water-inlet flowrate and gas cooler water-inlet temperature, on the heating process of the system are investigated from the perspective of thermal quality and heat capacity. The results shows that: In the heat transfer process of gas cooler, the temperature distribution of CO₂ and water shows a typical “two region” and “three zone” pattern; The rise in the cooling pressure of CO₂ serves to increase the thermal quality on the CO₂ side of the gas cooler, which in turn improves the heating temperature of the system; Nevertheless, the elevated thermal quality on the CO₂ side can exacerbate the mismatch of heat capacity on both sides of the gas cooler, thereby adversely affecting the system coefficient of performance (COP); Furthermore, increasing compressor speed mitigates the mismatch in heat capacity caused by elevated thermal quality, which is exacerbated by decreasing gas cooler water-inlet flowrate and rising gas cooler water-inlet temperature; As a delegate, the varying compressor speed results in a 7.1°C increase in heating temperature within the experimental range, accompanied by a 10.01% decrease in COP and an 11.36% increase in heating capacity. This study can not only provide an important reference for the theoretical analysis and control strategy of the transcritical CO₂ heat pump, but also guide the related simulation and the design of the gas cooler. However, the range of experimental parameters in the current study is small and the conclusions drawn are not further analysed quantitatively. Therefore, expanding the range of parameters studied and proposing corresponding quantitative conclusions and indicators with universal applicability could greatly increase the practical applicability of this study. This is also the goal of our next research.

Keywords: transcritical CO₂ heat pump, gas cooler, heat capacity, thermal quality

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4059 Investigation of the Effect of Nano-Alumina Particles on Adsorption Property of Acrylic Fiber

Authors: Mehdi Ketabchi, Shallah Alijanlo

Abstract:

The flue gas from fossil fuels combustion contains harmful pollutants dangerous for human health and environment. One of the air pollution control methods to restrict the emission of these pollutants is based on using the nanoparticle in adsorption process. In the present research, gamma nano-alumina particle is added to polyacrylonitrile (PAN) polymer through simple loading method, and the adsorption capacity of the wet spun fiber is investigated. The results of exposure the fiber to the acid gases including SO2, CO, NO2, NO, and CO2 show the noticeable increase of gas adsorption capacity on fiber contains nanoparticle. The research has been conducted in Acrylic II Plant of Polyacryl Iran Corporation.

Keywords: acrylic fiber, adsorbent, wet spun, polyacryl company, nano gamma alumina

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4058 Chipless RFID Capacity Enhancement Using the E-pulse Technique

Authors: Haythem H. Abdullah, Hesham Elkady

Abstract:

With the fast increase in radio frequency identification (RFID) applications such as medical recording, library management, etc., the limitation of active tags stems from its need to external batteries as well as passive or active chips. The chipless RFID tag reduces the cost to a large extent but at the expense of utilizing the spectrum. The reduction of the cost of chipless RFID is due to the absence of the chip itself. The identification is done by utilizing the spectrum in such a way that the frequency response of the tags consists of some resonance frequencies that represent the bits. The system capacity is decided by the number of resonators within the pre-specified band. It is important to find a solution to enhance the spectrum utilization when using chipless RFID. Target identification is a process that results in a decision that a specific target is present or not. Several target identification schemes are present, but one of the most successful techniques in radar target identification in the oscillatory region is the extinction pulse technique (E-Pulse). The E-Pulse technique is used to identify targets via its characteristics (natural) modes. By introducing an innovative solution for chipless RFID reader and tag designs, the spectrum utilization goes to the optimum case. In this paper, a novel capacity enhancement scheme based on the E-pulse technique is introduced to improve the performance of the chipless RFID system.

Keywords: chipless RFID, E-pulse, natural modes, resonators

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4057 An Approach for the Capture of Carbon Dioxide via Polymerized Ionic Liquids

Authors: Ghassan Mohammad Alalawi, Abobakr Khidir Ziyada, Abdulmajeed Khan

Abstract:

A potential alternative or next-generation CO₂-selective separation medium that has lately been suggested is ionic liquids (ILs). It is more facile to "tune" the solubility and selectivity of CO₂ in ILs compared to organic solvents via modification of the cation and/or anion structures. Compared to ionic liquids at ambient temperature, polymerized ionic liquids exhibited increased CO₂ sorption capacities and accelerated sorption/desorption rates. This research aims to investigate the correlation between the CO₂ sorption rate and capacity of poly ionic liquids (pILs) and the chemical structure of these substances. The dependency of sorption on the ion conductivity of the pILs' cations and anions is one of the theories we offered to explain the attraction between CO₂ and pILs. This assumption was supported by the Monte Carlo molecular dynamics simulations results, which demonstrated that CO₂ molecules are localized around both cations and anions and that their sorption depends on the cations' and anions' ion conductivities. Polymerized ionic liquids are synthesized to investigate the impact of substituent alkyl chain length, cation, and anion on CO₂ sorption rate and capacity. Three stages are involved in synthesizing the pILs under study: first, trialkyl amine and vinyl benzyl chloride are directly quaternized to obtain the required cation. Next, anion exchange is performed, and finally, the obtained IL is polymerized to form the desired product (pILs). The synthesized pILs' structures were confirmed using elemental analysis and NMR. The synthesized pILs are characterized by examining their structure topology, chloride content, density, and thermal stability using SEM, ion chromatography (using a Metrohm Model 761 Compact IC apparatus), ultrapycnometer, and TGA. As determined by the CO₂ sorption results using a magnetic suspension balance (MSB) apparatus, the sorption capacity of pILs is dependent on the cation and anion ion conductivities. The anion's size also influences the CO₂ sorption rate and capacity. It was discovered that adding water to pILs caused a dramatic, systematic enlargement of pILs resulting in a significant increase in their capacity to absorb CO₂ under identical conditions, contingent on the type of gas, gas flow, applied gas pressure, and water content of the pILs. Along with its capacity to increase surface area through expansion, water also possesses highly high ion conductivity for cations and anions, enhancing its ability to absorb CO₂.

Keywords: polymerized ionic liquids, carbon dioxide, swelling, characterization

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