Search results for: curing agent
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1834

Search results for: curing agent

1564 Biochar Affects Compressive Strength of Portland Cement Composites: A Meta-Analysis

Authors: Zhihao Zhao, Ali El-Nagger, Johnson Kau, Chris Olson, Douglas Tomlinson, Scott X. Chang

Abstract:

One strategy to reduce CO₂ emissions from cement production is to reduce the amount of Portland cement produced by replacing it with supplementary cementitious materials (SCMs). Biochar is a potential SCM that is an eco-friendly and stable porous pyrolytic material. However, the effects of biochar addition on the performances of Portland cement composites are not fully understood. This meta-analysis investigated the impact of biochar addition on the 7- and 28-day compressive strength of Portland cement composites based on 606 paired observations. Biochar feedstock type, pyrolysis conditions, pre-treatments and modifications, biochar dosage, and curing type all influenced the compressive strength of Portland cement composites. Biochars obtained from plant-based feedstocks (except rice and hardwood) improved the 28-day compressive strength of Portland cement composites by 3-13%. Biochars produced at pyrolysis temperatures higher than 450 °C, with a heating rate of around 10 °C/min, increased the 28-day compressive strength more effectively. Furthermore, the addition of biochars with small particle sizes increased the compressive strength of Portland cement composites by 2-7% compared to those without biochar addition. Biochar dosage of < 2.5% of the binder weight enhanced both compressive strengths and common curing methods maintained the effect of biochar addition. However, when mixing the cement, adding fine and coarse aggregates such as sand and gravel affects the concrete and mortar's compressive strength, diminishing the effect of biochar addition and making the biochar effect nonsignificant. We conclude that appropriate biochar addition could maintain or enhance the mechanical performance of Portland cement composites, and future research should explore the mechanisms of biochar effects on the performance of cement composites.

Keywords: biochar, Portland cement, constructure, compressive strength, meta-analysis

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1563 Phytoremediation Waste Processing of Coffee in Various Concentration of Organic Materials Plant Using Kiambang

Authors: Siti Aminatu Zuhria

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On wet coffee processing can improve the quality of coffee, but the coffee liquid waste that can pollute the environment. Liquid waste a lot of coffee resulting from the stripping and washing the coffee. This research will be carried out the process of handling liquid waste stripping coffee from the coffee skin with media phytoremediation using plants kiambang. The purpose of this study was to determine the characteristics of the coffee liquid waste and plant phytoremediation kiambang as agent in various concentrations of liquid waste coffee as well as determining the most optimal concentration in the improved quality of waste water quality standard approach. This research will be conducted through two stages, namely the preliminary study and the main study. In a preliminary study aims to determine the ability of the plant life kiambang as phytoremediation agent in the media well water, distilled water and liquid waste coffee. The main study will be conducted wastewater dilution and coffee will be obtained COD concentration variations. Results are expected at this research that can determine the ability of plants kiambang as an agent for phytoremediation in wastewater treatment with various concentrations of waste and the most optimal concentration in the improved quality of waste water quality standard approach.

Keywords: wet coffee processing, phytoremediation, Kiambang plant, variation concentration liquid waste

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1562 Assessing the Potential of a Waste Material for Cement Replacement and the Effect of Its Fineness in Soft Soil Stabilisation

Authors: Hassnen M. Jafer, W. Atherton, F. Ruddock

Abstract:

This paper represents the results of experimental work to investigate the suitability of a waste material (WM) for soft soil stabilisation. In addition, the effect of particle size distribution (PSD) of the waste material on its performance as a soil stabiliser was investigated. The WM used in this study is produced from the incineration processes in domestic energy power plant and it is available in two different grades of fineness (coarse waste material (CWM) and fine waste material (FWM)). An intermediate plasticity silty clayey soil with medium organic matter content has been used in this study. The suitability of the CWM and FWM to improve the physical and engineering properties of the selected soil was evaluated dependant on the results obtained from the consistency limits, compaction characteristics (optimum moisture content (OMC) and maximum dry density (MDD)); along with the unconfined compressive strength test (UCS). Different percentages of CWM were added to the soft soil (3, 6, 9, 12 and 15%) to produce various admixtures. Then the UCS test was carried out on specimens under different curing periods (zero, 7, 14, and 28 days) to find the optimum percentage of CWM. The optimum and other two percentages (either side of the optimum content) were used for FWM to evaluate the effect of the fineness of the WM on UCS of the stabilised soil. Results indicated that both types of the WM used in this study improved the physical properties of the soft soil where the index of plasticity (IP) was decreased significantly. IP was decreased from 21 to 13.64 and 13.10 with 12% of CWM and 15% of FWM respectively. The results of the unconfined compressive strength test indicated that 12% of CWM was the optimum and this percentage developed the UCS value from 202kPa to 500kPa for 28 days cured samples, which is equal, approximately 2.5 times the UCS value for untreated soil. Moreover, this percentage provided 1.4 times the value of UCS for stabilized soil-CWA by using FWM which recorded just under 700kPa after 28 days curing.

Keywords: soft soil stabilisation, waste materials, fineness, unconfined compressive strength

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1561 Reactive Fabrics for Chemical Warfare Agent Decomposition Using Particle Crystallization

Authors: Myungkyu Park, Minkun Kim, Sunghoon Kim, Samgon Ryu

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Recently, research for reactive fabrics which have the characteristics of CWA (Chemical Warfare Agent) decomposition is being performed actively. The performance level of decomposition for CWA decomposition in various environmental condition is one of the critical factors in applicability as protective materials for NBC (Nuclear, Biological, and Chemical) protective clothing. In this study, results of performance test for CWA decomposition by reactive fabric made of electrospinning web and reactive particle are presented. Currently, the MOF (metal organic framework) type of UiO-66-NH₂ is frequently being studied as material for decomposing CWA especially blister agent HD [Bis(2-chloroethyl) sulfide]. When we test decomposition rate with electrospinning web made of PVB (Polyvinyl Butiral) polymer and UiO-66-NH₂ particle, we can get very high protective performance than the case other particles are applied. Furthermore, if the repellant surface fabric is added on reactive material as the component of protective fabric, the performance of layer by layered reactive fabric could be approached to the level of current NBC protective fabric for HD decomposition rate. Reactive fabric we used in this study is manufactured by electrospinning process of polymer which contains the reactive particle of UiO-66-NH₂, and we performed crystalizing process once again on that polymer fiber web in solvent systems as a second step for manufacturing reactive fabric. Three kinds of polymer materials are used in this process, but PVB was most suitable as an electrospinning fiber polymer considering the shape of product. The density of particle on fiber web and HD decomposition rate is enhanced by secondary crystallization compared with the results which are not processed. The amount of HD penetration by 24hr AVLAG (Aerosol Vapor Liquid Assessment Group) swatch test through the reactive fabrics with secondary crystallization and without crystallization is 24 and 146μg/cm² respectively. Even though all of the reactive fiber webs for this test are combined with repellant surface layer at outer side of swatch, the effects of secondary crystallization of particle for the reactive fiber web are remarkable.

Keywords: CWA, Chemical Warfare Agent, gas decomposition, particle growth, protective clothing, reactive fabric, swatch test

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1560 Therapeutic Potential of Cannabis in Cancer: Advances in Clinical Research and Pharmacogenomic Aspects

Authors: Bouchaïb Gazzaz, Hamid El Amri, Hind Dehbi, Abderraouf Hilali

Abstract:

Medical cannabis has been cultivated and used in many countries around the world. The story of the use of cannabis as a therapeutic agent is difficult to trace, in particular, because the laws regulating its production, distribution, possession, and consumption are relatively recent. Nowadays, in countries where it is authorized, medical cannabis is used in a very wide variety of illnesses and pathologies, particularly in cancer cures. Presently, cannabinoid receptor agonists (like nabilone and dronabinol) are used for reducing chemotherapy induced vomiting. This review aims to discuss a recent finding on the use of therapeutic cannabis in patients with cancer. First, this work addresses the progress made in the use of cannabinoids as therapeutic agent and their application in the treatment of different types of cancer. Secondly, a detailed analysis of the pharmacogenetic aspect of cannabis will be discussed.

Keywords: cannabinoids, endocannabinoids system, cancer treatment, cannabinoid receptors, genetic polymorphism, pharmacogenomics

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1559 Optimization of Traffic Agent Allocation for Minimizing Bus Rapid Transit Cost on Simplified Jakarta Network

Authors: Gloria Patricia Manurung

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Jakarta Bus Rapid Transit (BRT) system which was established in 2009 to reduce private vehicle usage and ease the rush hour gridlock throughout the Jakarta Greater area, has failed to achieve its purpose. With gradually increasing the number of private vehicles ownership and reduced road space by the BRT lane construction, private vehicle users intuitively invade the exclusive lane of BRT, creating local traffic along the BRT network. Invaded BRT lanes costs become the same with the road network, making BRT which is supposed to be the main public transportation in the city becoming unreliable. Efforts to guard critical lanes with preventing the invasion by allocating traffic agents at several intersections have been expended, lead to the improving congestion level along the lane. Given a set of number of traffic agents, this study uses an analytical approach to finding the best deployment strategy of traffic agent on a simplified Jakarta road network in minimizing the BRT link cost which is expected to lead to the improvement of BRT system time reliability. User-equilibrium model of traffic assignment is used to reproduce the origin-destination demand flow on the network and the optimum solution conventionally can be obtained with brute force algorithm. This method’s main constraint is that traffic assignment simulation time escalates exponentially with the increase of set of agent’s number and network size. Our proposed metaheuristic and heuristic algorithms perform linear simulation time increase and result in minimized BRT cost approaching to brute force algorithm optimization. Further analysis of the overall network link cost should be performed to see the impact of traffic agent deployment to the network system.

Keywords: traffic assignment, user equilibrium, greedy algorithm, optimization

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1558 Influence of Pine Wood Ash as Pozzolanic Material on Compressive Strength of a Concrete

Authors: M. I. Nicolas, J. C. Cruz, Ysmael Verde, A.Yeladaqui-Tello

Abstract:

The manufacture of Portland cement has revolutionized the construction industry since the nineteenth century; however, the high cost and large amount of energy required on its manufacturing encouraged, from the seventies, the search of alternative materials to replace it partially or completely. Among the materials studied to replace the cement are the ashes. In the city of Chetumal, south of the Yucatan Peninsula in Mexico, there are no natural sources of pozzolanic ash. In the present study, the cementitious properties of artificial ash resulting from the combustion of waste pine wood were analyzed. The ash obtained was sieved through the screen and No.200 a fraction was analyzed using the technique of X-ray diffraction; with the aim of identifying the crystalline phases and particle sizes of pozzolanic material by the Debye-Scherrer equation. From the characterization of materials, mixtures for a concrete of f'c = 250 kg / cm2 were designed with the method ACI 211.1; for the pattern mixture and for partial replacements of Portland cement by 5%, 10% and 12% pine wood ash mixture. Simple resistance to axial compression of specimens prepared with each concrete mixture, at 3, 14 and 28 days of curing was evaluated. Pozzolanic activity was observed in the ash obtained, checking the presence of crystalline silica (SiO2 of 40.24 nm) and alumina (Al2O3 of 35.08 nm). At 28 days of curing, the specimens prepared with a 5% ash, reached a compression resistance 63% higher than design; for specimens with 10% ash, was 45%; and for specimens with 12% ash, only 36%. Compared to Pattern mixture, which after 28 days showed a f'c = 423.13 kg/cm2, the specimens reached only 97%, 86% and 82% of the compression resistance, for mixtures containing 5%, 10% ash and 12% respectively. The pozzolanic activity of pine wood ash influences the compression resistance, which indicates that it can replace up to 12% of Portland cement by ash without compromising its design strength, however, there is a decrease in strength compared to the pattern concrete.

Keywords: concrete, pine wood ash, pozzolanic activity, X-ray

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1557 Impact of Alkaline Activator Composition and Precursor Types on Properties and Durability of Alkali-Activated Cements Mortars

Authors: Sebastiano Candamano, Antonio Iorfida, Patrizia Frontera, Anastasia Macario, Fortunato Crea

Abstract:

Alkali-activated materials are promising binders obtained by an alkaline attack on fly-ashes, metakaolin, blast slag among others. In order to guarantee the highest ecological and cost efficiency, a proper selection of precursors and alkaline activators has to be carried out. These choices deeply affect the microstructure, chemistry and performances of this class of materials. Even if, in the last years, several researches have been focused on mix designs and curing conditions, the lack of exhaustive activation models, standardized mix design and curing conditions and an insufficient investigation on shrinkage behavior, efflorescence, additives and durability prevent them from being perceived as an effective and reliable alternative to Portland. The aim of this study is to develop alkali-activated cements mortars containing high amounts of industrial by-products and waste, such as ground granulated blast furnace slag (GGBFS) and ashes obtained from the combustion process of forest biomass in thermal power plants. In particular, the experimental campaign was performed in two steps. In the first step, research was focused on elucidating how the workability, mechanical properties and shrinkage behavior of produced mortars are affected by the type and fraction of each precursor as well as by the composition of the activator solutions. In order to investigate the microstructures and reaction products, SEM and diffractometric analyses have been carried out. In the second step, their durability in harsh environments has been evaluated. Mortars obtained using only GGBFS as binder showed mechanical properties development and shrinkage behavior strictly dependent on SiO2/Na2O molar ratio of the activator solutions. Compressive strengths were in the range of 40-60 MPa after 28 days of curing at ambient temperature. Mortars obtained by partial replacement of GGBFS with metakaolin and forest biomass ash showed lower compressive strengths (≈35 MPa) and shrinkage values when higher amount of ashes were used. By varying the activator solutions and binder composition, compressive strength up to 70 MPa associated with shrinkage values of about 4200 microstrains were measured. Durability tests were conducted to assess the acid and thermal resistance of the different mortars. They all showed good resistance in a solution of 5%wt of H2SO4 also after 60 days of immersion, while they showed a decrease of mechanical properties in the range of 60-90% when exposed to thermal cycles up to 700°C.

Keywords: alkali activated cement, biomass ash, durability, shrinkage, slag

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1556 Modern Scotland Yard: Improving Surveillance Policies Using Adversarial Agent-Based Modelling and Reinforcement Learning

Authors: Olaf Visker, Arnout De Vries, Lambert Schomaker

Abstract:

Predictive policing refers to the usage of analytical techniques to identify potential criminal activity. It has been widely implemented by various police departments. Being a relatively new area of research, there are, to the author’s knowledge, no absolute tried, and true methods and they still exhibit a variety of potential problems. One of those problems is closely related to the lack of understanding of how acting on these prediction influence crime itself. The goal of law enforcement is ultimately crime reduction. As such, a policy needs to be established that best facilitates this goal. This research aims to find such a policy by using adversarial agent-based modeling in combination with modern reinforcement learning techniques. It is presented here that a baseline model for both law enforcement and criminal agents and compare their performance to their respective reinforcement models. The experiments show that our smart law enforcement model is capable of reducing crime by making more deliberate choices regarding the locations of potential criminal activity. Furthermore, it is shown that the smart criminal model presents behavior consistent with popular crime theories and outperforms the baseline model in terms of crimes committed and time to capture. It does, however, still suffer from the difficulties of capturing long term rewards and learning how to handle multiple opposing goals.

Keywords: adversarial, agent based modelling, predictive policing, reinforcement learning

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1555 Blindness and Deafness, the Outcomes of Varicella Zoster Virus Encephalitis in HIV Positive Patient

Authors: Hadiseh Hosamirudsari, Farhad Afsarikordehmahin, Pooria Sekhavatfar

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Concomitant cortical blindness and deafness that follow varicella zoster virus (VZV) infection is rare. We describe a case of ophthalmic zoster that caused cortical blindness and deafness after central nervous system (CNS) involvement. A 42-year old, HIV infected woman has developed progressive blurry vision and deafness, 4 weeks after ophthalmic zoster. A physical examination and positive VZV polymerase chain reaction (PCR) of cerebrospinal fluid (CSF) suggested VZV encephalitis. Complication of VZV encephalitis is considered as the cause of blindness and deafness. In neurological deficit patient especially with a history of herpes zoster, VZV infection should be regarded as the responsible agent in inflammatory disorders of nervous system. The immunocompromised state of patient (including HIV) is as important an agent as VZV infection in developing the disease.

Keywords: blindness, deafness, hiv, VZV encephalitis

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1554 A Game-Theory-Based Price-Optimization Algorithm for the Simulation of Markets Using Agent-Based Modelling

Authors: Juan Manuel Sanchez-Cartas, Gonzalo Leon

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A price competition algorithm for ABMs based on game theory principles is proposed to deal with the simulation of theoretical market models. The algorithm is applied to the classical Hotelling’s model and to a two-sided market model to show it leads to the optimal behavior predicted by theoretical models. However, when theoretical models fail to predict the equilibrium, the algorithm is capable of reaching a feasible outcome. Results highlight that the algorithm can be implemented in other simulation models to guarantee rational users and endogenous optimal behaviors. Also, it can be applied as a tool of verification given that is theoretically based.

Keywords: agent-based models, algorithmic game theory, multi-sided markets, price optimization

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1553 An Investigation of Foam Glass Production from Sheet Glass Waste and SiC Foaming Agent

Authors: Aylin Sahin, Recep Artir, Mustafa Kara

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Foam glass is a remarkable material with having incomparable properties like low weight, rigidity, high thermal insulation capacity and porous structure. In this study, foam glass production was investigated with using glass powder from sheet glass waste and SiC powder as foaming agent. Effects of SiC powders and sintering temperatures on foaming process were examined. It was seen that volume expansions (%), cellular structures and pore diameters of obtained foam glass samples were highly depending on composition ratios and sintering temperature. The study showed that various foam glass samples having with homogenous closed porosity, low weight and low thermal conductivity were achieved by optimizing composition ratios and sintering temperatures.

Keywords: foam glass, foaming, waste glass, silicon carbide

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1552 A Distributed Mobile Agent Based on Intrusion Detection System for MANET

Authors: Maad Kamal Al-Anni

Abstract:

This study is about an algorithmic dependence of Artificial Neural Network on Multilayer Perceptron (MPL) pertaining to the classification and clustering presentations for Mobile Adhoc Network vulnerabilities. Moreover, mobile ad hoc network (MANET) is ubiquitous intelligent internetworking devices in which it has the ability to detect their environment using an autonomous system of mobile nodes that are connected via wireless links. Security affairs are the most important subject in MANET due to the easy penetrative scenarios occurred in such an auto configuration network. One of the powerful techniques used for inspecting the network packets is Intrusion Detection System (IDS); in this article, we are going to show the effectiveness of artificial neural networks used as a machine learning along with stochastic approach (information gain) to classify the malicious behaviors in simulated network with respect to different IDS techniques. The monitoring agent is responsible for detection inference engine, the audit data is collected from collecting agent by simulating the node attack and contrasted outputs with normal behaviors of the framework, whenever. In the event that there is any deviation from the ordinary behaviors then the monitoring agent is considered this event as an attack , in this article we are going to demonstrate the  signature-based IDS approach in a MANET by implementing the back propagation algorithm over ensemble-based Traffic Table (TT), thus the signature of malicious behaviors or undesirable activities are often significantly prognosticated and efficiently figured out, by increasing the parametric set-up of Back propagation algorithm during the experimental results which empirically shown its effectiveness  for the ratio of detection index up to 98.6 percentage. Consequently it is proved in empirical results in this article, the performance matrices are also being included in this article with Xgraph screen show by different through puts like Packet Delivery Ratio (PDR), Through Put(TP), and Average Delay(AD).

Keywords: Intrusion Detection System (IDS), Mobile Adhoc Networks (MANET), Back Propagation Algorithm (BPA), Neural Networks (NN)

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1551 Effect of the Hardness of Spacer Agent on Structural Properties of Metallic Scaffolds

Authors: Mohammad Khodaei, Mahmood Meratien, Alireza Valanezhad, Serdar Pazarlioglu, Serdar Salman, Ikuya Watanabe

Abstract:

Pore size and morphology plays a crucial role on mechanical properties of porous scaffolds. In this research, titanium scaffold was prepared using space holder technique. Sodium chloride and ammonium bicarbonate were utilized as spacer agent separately. The effect of the hardness of spacer on the cell morphology was investigated using scanning electron microscopy (SEM) and optical stereo microscopy. Image analyzing software was used to interpret the microscopic images quantitatively. It was shown that sodium chloride, due to its higher hardness, maintain its morphology during cold compaction, and cause better replication in porous scaffolds.

Keywords: Spacer, Titanium Scaffold, Pore Morphology, Space Holder Technique

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1550 Contribution to Energy Management in Hybrid Energy Systems Based on Agents Coordination

Authors: Djamel Saba, Fatima Zohra Laallam, Brahim Berbaoui

Abstract:

This paper presents a contribution to the design of a multi-agent for the energy management system in a hybrid energy system (SEH). The multi-agent-based energy-coordination management system (MA-ECMS) is based mainly on coordination between agents. The agents share the tasks and exchange information through communications protocols to achieve the main goal. This intelligent system can fully manage the consumption and production or simply to make proposals for action he thinks is best. The initial step is to give a presentation for the system that we want to model in order to understand all the details as much as possible. In our case, it is to implement a system for simulating a process control of energy management.

Keywords: communications protocols, control process, energy management, hybrid energy system, modelization, multi-agents system, simulation

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1549 Chelator-assisted Phytoextraction of Nickel from Nickeliferous Lateritic Soil by Phyllanthus sp. nov.

Authors: Grecco M. Ante, Princess Rochelle O. Gan

Abstract:

Plants that can absorb greater than 10,000 µg Ni/g dry mass in their stems and leaves are termed as ‘hypernickelophores’. Chelators are chemicals that make the metals in the soil more soluble, making them a potential enhancer for phytoextraction. This study aims to observe the effect of different concentrations of the chelating agent ethylene diamine tetraacetate (EDTA) on the metal uptake (or rate of phytoextraction) of Nickel by Phyllanthus sp. nov. The plant is found to be a hyperickelophore in normal conditions. The addition of EDTA increased the metal uptake of the plant. The increasing amount of the chelating agent causes a decrease in the phytoextraction of the plant but moves the onset of its peak of maximum nickel content in its tissue to an earlier time. The chelator-assisted phytoextraction of nickel by Phyllanthus sp. nov. is proven to be an efficient auxiliary mining operation for nickel laterite mines.

Keywords: phytomining, Phyllanthus sp. nov., EDTA, nickel, laterite

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1548 Early Age Microstructural Analysis of Cement-Polymer Composite Paste Cured at High Temperature

Authors: Bertilia L. Bartley, Ledjane S. Barreto

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As a preliminary investigation on the control of microcracking in composite cement pastes, this study explores and compares the compatibility of Tetraethyl Orthosilicate (TEOS), Ethylene Glycol (EG) and Silicone Resin (SIL) in cement pastes cured at high temperature. Pastes were prepared by incorporating ordinary Portland cement (OPC) into an additive solution, using a solution/cement ratio of 0.45. Specimens were molded for 24h at 21 ± 2°C, then cured in deionized water for another 24h at 74 ± 1°C. TEOS and EG influence on fresh paste properties were similar to the reference OPC paste yet disintegration was observed in EG and SIL specimens after the first 12h of curing. X-Ray Diffraction analysis (XRD) coupled with thermogravimetric analysis (TGA/DTG) verified that SIL addition impedes portlandite formation significantly. Backscatter Scanning Electron Microscopy (SEM) techniques were therefore performed on selected areas of each sample to investigate the morphology of the hydration products detected. Various morphologies of portlandite crystals were observed in pastes with EG and TEOS addition, as well as dense morphologies of calcium silicate hydrate (C-S-H) gel and fibers, and ettringite needles. However, the formation of portlandite aggregate and clusters of C-S-H was highly favored by TEOS addition. Furthermore, the microstructural details of composite pastes were clearly visible at low magnifications i.e. 500x, as compared to the OPC paste. The results demonstrate accelerated hydration within composite pastes, a uniform distribution of hydration products, as well as an adhesive interaction with the products and polymer additive. Overall, TEOS demonstrated the most favorable influence, which indicates the potential of TEOS as a compatible polymer additive within the cement system at high temperature.

Keywords: accelerated curing, cement/polymer composite, hydration, microstructural properties, morphology, portlandite, scanning electron microscopy (sem)

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1547 Effect of Edta in the Phytoextraction of Copper by Terminalia catappa (Talisay) Linnaeus

Authors: Ian Marc G. Cabugsa, Zarine M. Hermita

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Phytoextraction capability of T. catappa in contaminated soils was done in the improvised greenhouse. The plant samples were planted to the soil which contained different concentrations of copper. Chelating agent EDTA was added to observe the uptake and translocation of copper in the plant samples. Results showed a significant increase of copper accumulation with the addition of EDTA at 250 and 1250 mgˑkg-1 concentration of copper in the contaminated soils (p<0.05). While translocation of copper was observed in all treatments, translocation of copper is not significantly enhanced by the addition of EDTA (p>0.05). Uptake and translocation were not directly affected the presence of EDTA. Furthermore, this study suggests that the T. catappa is not a hyperaccumulator of copper, and there is no relationship observed between the length of the plant and the copper uptake in all treatments.

Keywords: chelating agent EDTA, hyperaccumulator, phytoextraction, phytoremediation, terminalia catappa

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1546 Agent-Base Modeling of IoT Applications by Using Software Product Line

Authors: Asad Abbas, Muhammad Fezan Afzal, Muhammad Latif Anjum, Muhammad Azmat

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The Internet of Things (IoT) is used to link up real objects that use the internet to interact. IoT applications allow handling and operating the equipment in accordance with environmental needs, such as transportation and healthcare. IoT devices are linked together via a number of agents that act as a middleman for communications. The operation of a heat sensor differs indoors and outside because agent applications work with environmental variables. In this article, we suggest using Software Product Line (SPL) to model IoT agents and applications' features on an XML-based basis. The contextual diversity within the same domain of application can be handled, and the reusability of features is increased by XML-based feature modelling. For the purpose of managing contextual variability, we have embraced XML for modelling IoT applications, agents, and internet-connected devices.

Keywords: IoT agents, IoT applications, software product line, feature model, XML

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1545 Automatic Calibration of Agent-Based Models Using Deep Neural Networks

Authors: Sima Najafzadehkhoei, George Vega Yon

Abstract:

This paper presents an approach for calibrating Agent-Based Models (ABMs) efficiently, utilizing Convolutional Neural Networks (CNNs) and Long Short-Term Memory (LSTM) networks. These machine learning techniques are applied to Susceptible-Infected-Recovered (SIR) models, which are a core framework in the study of epidemiology. Our method replicates parameter values from observed trajectory curves, enhancing the accuracy of predictions when compared to traditional calibration techniques. Through the use of simulated data, we train the models to predict epidemiological parameters more accurately. Two primary approaches were explored: one where the number of susceptible, infected, and recovered individuals is fully known, and another using only the number of infected individuals. Our method shows promise for application in other ABMs where calibration is computationally intensive and expensive.

Keywords: ABM, calibration, CNN, LSTM, epidemiology

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1544 Fabricating Method for Complex 3D Microfluidic Channel Using Soluble Wax Mold

Authors: Kyunghun Kang, Sangwoo Oh, Yongha Hwang

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PDMS (Polydimethylsiloxane)-based microfluidic device has been recently applied to area of biomedical research, tissue engineering, and diagnostics because PDMS is low cost, nontoxic, optically transparent, gas-permeable, and especially biocompatible. Generally, PDMS microfluidic devices are fabricated by conventional soft lithography. Microfabrication requires expensive cleanroom facilities and a lot of time; however, only two-dimensional or simple three-dimensional structures can be fabricated. In this study, we introduce fabricating method for complex three-dimensional microfluidic channels using soluble wax mold. Using the 3D printing technique, we firstly fabricated three-dimensional mold which consists of soluble wax material. The PDMS pre-polymer is cast around, followed by PDMS casting and curing. The three-dimensional casting mold was removed from PDMS by chemically dissolved with methanol and acetone. In this work, two preliminary experiments were carried out. Firstly, the solubility of several waxes was tested using various solvents, such as acetone, methanol, hexane, and IPA. We found the combination between wax and solvent which dissolves the wax. Next, side effects of the solvent were investigated during the curing process of PDMS pre-polymer. While some solvents let PDMS drastically swell, methanol and acetone let PDMS swell only 2% and 6%, respectively. Thus, methanol and acetone can be used to dissolve wax in PDMS without any serious impact. Based on the preliminary tests, three-dimensional PDMS microfluidic channels was fabricated using the mold which was printed out using 3D printer. With the proposed fabricating technique, PDMS-based microfluidic devices have advantages of fast prototyping, low cost, optically transparence, as well as having complex three-dimensional geometry. Acknowledgements: This research was supported by Supported by a Korea University Grant and Basic Science Research Program through the National Research Foundation of Korea(NRF).

Keywords: microfluidic channel, polydimethylsiloxane, 3D printing, casting

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1543 Mobile Agents-Based Framework for Dynamic Resource Allocation in Cloud Computing

Authors: Safia Rabaaoui, Héla Hachicha, Ezzeddine Zagrouba

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Nowadays, cloud computing is becoming the more popular technology to various companies and consumers, which benefit from its increased efficiency, cost optimization, data security, unlimited storage capacity, etc. One of the biggest challenges of cloud computing is resource allocation. Its efficiency directly influences the performance of the whole cloud environment. Finding an effective method to address these critical issues and increase cloud performance was necessary. This paper proposes a mobile agents-based framework for dynamic resource allocation in cloud computing to minimize both the cost of using virtual machines and the makespan. Furthermore, its impact on the best response time and power consumption has been studied. The simulation showed that our method gave better results than here.

Keywords: cloud computing, multi-agent system, mobile agent, dynamic resource allocation, cost, makespan

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1542 Multi-Agent System Based Distributed Voltage Control in Distribution Systems

Authors: A. Arshad, M. Lehtonen. M. Humayun

Abstract:

With the increasing Distributed Generation (DG) penetration, distribution systems are advancing towards the smart grid technology for least latency in tackling voltage control problem in a distributed manner. This paper proposes a Multi-agent based distributed voltage level control. In this method a flat architecture of agents is used and agents involved in the whole controlling procedure are On Load Tap Changer Agent (OLTCA), Static VAR Compensator Agent (SVCA), and the agents associated with DGs and loads at their locations. The objectives of the proposed voltage control model are to minimize network losses and DG curtailments while maintaining voltage value within statutory limits as close as possible to the nominal. The total loss cost is the sum of network losses cost, DG curtailment costs, and voltage damage cost (which is based on penalty function implementation). The total cost is iteratively calculated for various stricter limits by plotting voltage damage cost and losses cost against varying voltage limit band. The method provides the optimal limits closer to nominal value with minimum total loss cost. In order to achieve the objective of voltage control, the whole network is divided into multiple control regions; downstream from the controlling device. The OLTCA behaves as a supervisory agent and performs all the optimizations. At first, a token is generated by OLTCA on each time step and it transfers from node to node until the node with voltage violation is detected. Upon detection of such a node, the token grants permission to Load Agent (LA) for initiation of possible remedial actions. LA will contact the respective controlling devices dependent on the vicinity of the violated node. If the violated node does not lie in the vicinity of the controller or the controlling capabilities of all the downstream control devices are at their limits then OLTC is considered as a last resort. For a realistic study, simulations are performed for a typical Finnish residential medium-voltage distribution system using Matlab ®. These simulations are executed for two cases; simple Distributed Voltage Control (DVC) and DVC with optimized loss cost (DVC + Penalty Function). A sensitivity analysis is performed based on DG penetration. The results indicate that costs of losses and DG curtailments are directly proportional to the DG penetration, while in case 2 there is a significant reduction in total loss. For lower DG penetration, losses are reduced more or less 50%, while for higher DG penetration, loss reduction is not very significant. Another observation is that the newer stricter limits calculated by cost optimization moves towards the statutory limits of ±10% of the nominal with the increasing DG penetration as for 25, 45 and 65% limits calculated are ±5, ±6.25 and 8.75% respectively. Observed results conclude that the novel voltage control algorithm proposed in case 1 is able to deal with the voltage control problem instantly but with higher losses. In contrast, case 2 make sure to reduce the network losses through proposed iterative method of loss cost optimization by OLTCA, slowly with time.

Keywords: distributed voltage control, distribution system, multi-agent systems, smart grids

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1541 Market Value of Ethno-Medicinally Important Plants of the Dughalgay Valley District Swat, Pakistan

Authors: Akbar Zeb, Shujaul Mulk Khan, Habib Ahmad, Manzoor Hussain, Mujtaba Shah

Abstract:

An ethnobotanical project was carried out in the Dughalgay valley District Swat in Hindu Kush region. The Local population not only use indigenous knowledge to use medicinal plants for curing various diseases but also earn their live hood by selling some of them in the local markets. An ethnobotanical project was carried out in the Doghalgay valley of upper Swat. The Local population not only use indigenous medicinal plants for curing various diseases but also earn their live hood by selling some of them in the local market. 102 of these medicinal plants were reported to be used in the region during questionnaire survey in spring 2007. Out of them 10 species are used as diuretic, 9 in stomachic and laxative each. Similarly 6, 5, 5, 4, 4, and 4 species of them are used as antiseptic, Anthelmintic, Carminative, Expectorant, Astringent and purgative respectively, while the remaining species have one or more than one medicinal use in the local community. 30 of these species are collected for marketing purposes, in which these medicinal plants such as Berberis lycium, Origanum vulgare, Bergenia ciliata, Aesculus indica, Podophyllum emodi, Pteredium aquilinum, Bergenia himalyca, Viola spp., Ajuga bracteosa, Morchella esculenta, Paeonia emodi, Atropa acuminate, Aconitum violaceum, Polygonum amplexicaulis, Bupleurum longicaule, Juglans regia, Diospyrus lotus, and Mentha longifolia are important. Study concluded that availability of medicinal plants is decreasing day by day due to human population pressure, marketing pressure, grazing and unwise collection. Therefore it is recommended that Governmental organizations and non Governmental organization should pay possible attention to make aware the local people about the future threats.

Keywords: indigenous knowledge, ethnomedicinal uses, marketing, Hindu Kush

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1540 Estimated Human Absorbed Dose of 111 In-BPAMD as a New Bone-Seeking Spect-Imaging Agent

Authors: H. Yousefnia, S. Zolghadri

Abstract:

An early diagnosis of bone metastases is very important for providing a profound decision on a subsequent therapy. A prerequisite for the clinical application of new diagnostic radiopharmaceutical is the measurement of organ radiation exposure dose from biodistribution data in animals. In this study, the dosimetric studies of a novel agent for SPECT-imaging of bone methastases, 111In-(4-{[(bis(phosphonomethyl))carbamoyl]methyl}-7,10-bis(carboxymethyl)-1,4,7,10-tetraazacyclododec-1-yl) acetic acid (111In-BPAMD) complex, have been estimated in human organs based on mice data. The radiolabeled complex was prepared with high radiochemical purity at the optimal conditions. Biodistribution studies of the complex were investigated in male Syrian mice at selected times after injection (2, 4, 24 and 48 h). The human absorbed dose estimation of the complex was performed based on mice data by the radiation absorbed dose assessment resource (RADAR) method. 111In-BPAMD complex was prepared with high radiochemical purity >95% (ITLC) and specific activities of 2.85 TBq/mmol. Total body effective absorbed dose for 111In-BPAMD was 0.205 mSv/MBq. This value is comparable to the other 111In clinically used complexes. The results show that the dose to critical organs the complex is well within the acceptable considered range for diagnostic nuclear medicine procedures. Generally, 111In-BPAMD has interesting characteristics and can be considered as a viable agent for SPECT-imaging of the bone metastases in the near future.

Keywords: In-111, BPAMD, absorbed dose, RADAR

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1539 Mineral Thermal Insulation Materials Based on Sodium Liquid Glass

Authors: Zin Min Htet, Tikhomirova Irina Nikolaevna, Karpenko Marina A.

Abstract:

In this paper, thermal insulation materials based on sodium liquid glass with light fillers as foam glass granules with different sizes and wollastonite - M325 (U.S.A production) were studied. Effective mineral thermal insulation materials are in demand in many industries because of their incombustibility and durability. A method for the preparation of such materials based on mechanically foamed sodium liquid glass and light mineral fillers is proposed. The thermal insulation properties depend on the type, amount of filler and on the foaming factor, which is determined by the concentration of the foaming agent. The water resistance of the material is provided by using an additive to neutralize the glass and transfer it to the silica gel.

Keywords: thermal insulation material, sodium liquid glass, foam glass granules, foaming agent, hardener, thermal conductivity, apparent density, compressive strength

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1538 Aqueous Extract of Picrorrhiza kurroa Royle ex Benth: A Potent Inhibitor of Human Topoisomerases

Authors: Syed Asif Hassan, Ritu Barthwal

Abstract:

Topoisomerase I and II α plays a crucial role in the DNA-maintenance in all living cells, and for this reason, inhibitors of this enzyme have been much studied. In this paper, we have described the inhibitory effect of the aqueous extract of Picrorrhiza kurroa on human topoisomerases by measuring the relaxation of superhelical plasmid pBR322 DNA. The aqueous extract inhibited topoisomerase I and II α in a concentration-dependent manner (Inhibitory concentration (IC) ≈ 25 and 50 µg, respectively). By stabilization studies of topoisomerase I-DNA complex and preincubation studies of topoisomerase I and II α with the extract; we conclude that the possible mechanism of inhibition is both; 1) stabilization of covalent complex of topo I-DNA complex and 2) direct inhibition of the enzyme topoisomerases. These findings might explain the antineoplastic activity of Picrorrhiza kurroa and encourage new studies to elucidate the usefulness of the extract as a potent antineoplastic agent.

Keywords: Picrorrhiza kurroa, topoisomerase I and II α, inhibition, antineoplastic agent

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1537 Decoding the Structure of Multi-Agent System Communication: A Comparative Analysis of Protocols and Paradigms

Authors: Gulshad Azatova, Aleksandr Kapitonov, Natig Aminov

Abstract:

Multiagent systems have gained significant attention in various fields, such as robotics, autonomous vehicles, and distributed computing, where multiple agents cooperate and communicate to achieve complex tasks. Efficient communication among agents is a crucial aspect of these systems, as it directly impacts their overall performance and scalability. This scholarly work provides an exploration of essential communication elements and conducts a comparative assessment of diverse protocols utilized in multiagent systems. The emphasis lies in scrutinizing the strengths, weaknesses, and applicability of these protocols across various scenarios. The research also sheds light on emerging trends within communication protocols for multiagent systems, including the incorporation of machine learning methods and the adoption of blockchain-based solutions to ensure secure communication. These trends provide valuable insights into the evolving landscape of multiagent systems and their communication protocols.

Keywords: communication, multi-agent systems, protocols, consensus

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1536 Designing ZIF67 Derivatives Using Ammonia-Based Fluorine Complex as Structure-Directing Agent for Energy Storage Applications

Authors: Lu-Yin Lin

Abstract:

The morphology of electroactive material is highly related to energy storage ability. Structure-directing agent (SDA) can design electroactive materials with favorable surface properties. Zeolitic imidazolate framework 67 (ZIF67) is one of the potential electroactive materials for energy storage devices. The SDA concept is less applied to designing ZIF67 derivatives in previous studies. An in-situ technique with ammonium fluoride (NH₄F) as SDA is proposed to produce a ZIF67 derivative with highly improved energy storage ability. Attracted by the effective in-situ technique, the NH₄F, ammonium bifluoride (NH₄HF₂), and ammonium tetrafluoroborate (NH₄BF₄) are first used as SDA to synthesize ZIF67 derivatives in one-step solution process as electroactive material of energy storage devices. The mechanisms of forming ZIF67 derivatives synthesized with different SDAs are discussed to explain the SDA effects on physical and electrochemical properties. The largest specific capacitance (CF) of 1527.0 Fg-¹ and the capacity of 296.9 mAhg-¹ are obtained for the ZIF67 derivative prepared using NH₄BF₄ as SDA. The energy storage device composed of the optimal ZIF67 derivative and carbon electrodes presents a maximum energy density of 15.1 Whkg-¹ at the power density of 857 Wkg-¹. The CF retention of 90% and Coulombic efficiency larger than 98% are also obtained after 5000 cycles.

Keywords: ammonium bifluoride, ammonium tetrafluoroborate, energy storage device, one-step solution process, structure-directing agent, zeolitic imidazolate framework 67

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1535 UV-Cured Thiol-ene Based Polymeric Phase Change Materials for Thermal Energy Storage

Authors: M. Vezir Kahraman, Emre Basturk

Abstract:

Energy storage technology offers new ways to meet the demand to obtain efficient and reliable energy storage materials. Thermal energy storage systems provide the potential to acquire energy savings, which in return decrease the environmental impact related to energy usage. For this purpose, phase change materials (PCMs) that work as 'latent heat storage units' which can store or release large amounts of energy are preferred. Phase change materials (PCMs) are being utilized to absorb, collect and discharge thermal energy during the cycle of melting and freezing, converting from one phase to another. Phase Change Materials (PCMs) can generally be arranged into three classes: organic materials, salt hydrates and eutectics. Many kinds of organic and inorganic PCMs and their blends have been examined as latent heat storage materials. PCMs have found different application areas such as solar energy storage and transfer, HVAC (Heating, Ventilating and Air Conditioning) systems, thermal comfort in vehicles, passive cooling, temperature controlled distributions, industrial waste heat recovery, under floor heating systems and modified fabrics in textiles. Ultraviolet (UV)-curing technology has many advantages, which made it applicable in many different fields. Low energy consumption, high speed, room-temperature operation, low processing costs, high chemical stability, and being environmental friendly are some of its main benefits. UV-curing technique has many applications. One of the many advantages of UV-cured PCMs is that they prevent the interior PCMs from leaking. Shape-stabilized PCM is prepared by blending the PCM with a supporting material, usually polymers. In our study, this problem is minimized by coating the fatty alcohols with a photo-cross-linked thiol-ene based polymeric system. Leakage is minimized because photo-cross-linked polymer acts a matrix. The aim of this study is to introduce a novel thiol-ene based shape-stabilized PCM. Photo-crosslinked thiol-ene based polymers containing fatty alcohols were prepared and characterized for the purpose of phase change materials (PCMs). Different types of fatty alcohols were used in order to investigate their properties as shape-stable PCMs. The structure of the PCMs was confirmed by ATR-FTIR techniques. The phase transition behaviors, thermal stability of the prepared photo-crosslinked PCMs were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). This work was supported by Marmara University, Commission of Scientific Research Project.

Keywords: differential scanning calorimetry (DSC), Polymeric phase change material, thermal energy storage, UV-curing

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