Search results for: socio ecological model
5977 Zero Valent Iron Algal Biocomposite for the Removal of Crystal Violet from Aqueous Solution: Box-Behnken Optimization and Fixed Bed Column Studies
Authors: M. Jerold, V. Sivasubramanian
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In this study, nano zero valent iron Sargassum swartzii (nZVI-SS) biocomposite a marine algal based biosorbent was used for the removal of simulated crystal violet (CV) in batch and continuous fixed bed operation. The Box-Behnen design (BBD) experimental results revealed the biosoprtion was maximum at pH 7.5, biosorbent dosage 0.1 g/L and initial CV concentration of 100 mg/L. The effect of various column parameters like bed depth (3, 6 and 9 cm), flow rate (5, 10 and 15 mL/min) and influent CV concentration (5, 10 and 15 mg/L) were investigated. The exhaustion time increased with increase of bed depth, influent CV concentration and decrease of flow rate. Adam-Bohart, Thomas and Yoon-Nelson models were used to predict the breakthrough curve and to evaluate the model parameters. Out of these models, Thomas and Yoon-Nelson models well described the experimental data. Therefore, the result implies that nZVI-SS biocomposite is a cheap and most promising biosorbent for the removal of CV from wastewater.Keywords: algae, biosorption, zero-valent, dye, wastewater
Procedia PDF Downloads 1955976 Multi-Criteria Evaluation of Integrated Renewable Energy Systems for Community-Scale Applications
Authors: Kuanrong Qiu, Sebnem Madrali, Evgueniy Entchev
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To achieve the satisfactory objectives in deploying integrated renewable energy systems, it is crucial to consider all the related parameters affecting the design and decision-making. The multi-criteria evaluation method is a reliable and efficient tool for achieving the most appropriate solution. The approach considers the influential factors and their relative importance in prioritizing the alternatives. In this paper, a multi-criteria decision framework, based on the criteria including technical, economic, environmental and reliability, is developed to evaluate and prioritize renewable energy technologies and configurations of their integrated systems for community applications, identify their viability, and thus support the adoption of the clean energy technologies and the decision-making regarding energy transitions and transition patterns. Case studies for communities in Canada show that resource availability and the configurations of the integrated systems significantly impact the economic performance and environmental performance.Keywords: multi-criteria, renewables, integrated energy systems, decision-making, model
Procedia PDF Downloads 935975 Modeling and Stability Analysis of Viral Propagation in Wireless Mesh Networking
Authors: Haowei Chen, Kaiqi Xiong
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This paper aims to answer how malware will propagate in Wireless Mesh Networks (WMNs) and how communication radius and distributed density of nodes affects the process of spreading. The above analysis is essential for devising network-wide strategies to counter malware. We answer these questions by developing an improved dynamical system that models malware propagation in the area where nodes were uniformly distributed. The proposed model captures both the spatial and temporal dynamics regarding the malware spreading process. Equilibrium and stability are also discussed based on the threshold of the system. If the threshold is less than one, the infected nodes disappear, and if the threshold is greater than one, the infected nodes asymptotically stabilize at the endemic equilibrium. Numerical simulations are investigated about communication radius and distributed density of nodes in WMNs, which allows us to draw various insights that can be used to guide security defense.Keywords: Bluetooth security, malware propagation, wireless mesh networks, stability analysis
Procedia PDF Downloads 985974 Study of Ground Level Electric Field under 800 kV HVDC Unipolar Laboratory level Transmission line
Authors: K. Urukundu, K. A. Aravind, Pradeep M. Nirgude, K. Sandhya
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Transmission of bulk power over a long distance through HVDC transmission lines is gaining importance. This is because the transfer of bulk power through HVDC, from generating stations to load centers over long distances is more economical. However, these HVDC transmission lines create environmental and interference effects under the right of way of the line due to the ionization of the surrounding atmosphere in the vicinity of HVDC lines. The measurement of ground-level electric field and ionic current density is essential for the evaluation of human effects due to electromagnetic interference of the HVDC transmission line. In this paper, experimental laboratory results of the ground-level electric field under the miniature model of 800 kV monopole HVDC line of length 8 meters are presented in lateral configuration with different heights of the conductor from the ground plane. The results are compared with the simulated test results obtained through Finite Element based software.Keywords: bundle, conductor, hexagonal, transmission line, ground-level electric field
Procedia PDF Downloads 2205973 Anti-Inflammatory Studies of Grewia crenata Leaves Extract in Albino Rats
Authors: A. N. Ukwuani, M. G. Abubakar, S. W. Hassan
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Grewia crenata is used locally in the treatment of fractured bones, wound healing and inflammatory conditions. The anti-inflammatory activity of hydromethanolic extract of G. crenata leaves was investigated using egg albumin induced-hind paw oedema model in albino rat. The extract produced a time-dependent inhibition of egg albumin induced-hind paw oedema at 30th minutes up to 150th minutes in all the groups compared to the control. Significant reduction (p<0.05) of hind paw oedema was observed 150 minutes after egg albumin injection. The percentage inhibition produced by the extract at 200 mg/kg (22.1%) was comparable to that produced by 10 mg/kg indomethacin (24.9%) at the 150th minutes of post-egg albumin injection. Preliminary qualitative phytochemical analysis revealed the presence of saponins, steroids, flavonoids, anthraquinones and glycosides. The results obtained in this study suggest that Grewia crenata can be a potential source of anti-inflammatory agent and validates its use in the treatment of inflammatory conditions.Keywords: Grewia crenata, anti-inflammatory, hind paw, oedema
Procedia PDF Downloads 3105972 Efficient Layout-Aware Pretraining for Multimodal Form Understanding
Authors: Armineh Nourbakhsh, Sameena Shah, Carolyn Rose
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Layout-aware language models have been used to create multimodal representations for documents that are in image form, achieving relatively high accuracy in document understanding tasks. However, the large number of parameters in the resulting models makes building and using them prohibitive without access to high-performing processing units with large memory capacity. We propose an alternative approach that can create efficient representations without the need for a neural visual backbone. This leads to an 80% reduction in the number of parameters compared to the smallest SOTA model, widely expanding applicability. In addition, our layout embeddings are pre-trained on spatial and visual cues alone and only fused with text embeddings in downstream tasks, which can facilitate applicability to low-resource of multi-lingual domains. Despite using 2.5% of training data, we show competitive performance on two form understanding tasks: semantic labeling and link prediction.Keywords: layout understanding, form understanding, multimodal document understanding, bias-augmented attention
Procedia PDF Downloads 1485971 The Research of Culture Heritage Tourism Loyalty in Taiwan
Authors: Chih-Wen Wu
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This study examines the antecedents of heritage tourism loyalty and its relation to destination image, consumer travel experience, and destination satisfaction in the tourism context. In this respect, a number of important questions concerning how destination image, consumer travel experience, and destination satisfaction impact destination loyalty are raised. This study attempts to identify three key antecedents of loyalty in the heritage context. The author empirically tests predicted relationships by using personal interview data from 475 foreign tourists. The conceptual model investigated the relevant relationships among the constructs by using confirmatory factor analysis(CFA) and structural equation modeling (SEM) approach. Findings from the research sample support the argument that destination image, consumer travel experience, destination satisfaction are the key determinants of destination loyalty. Destination image and consumer travel experience influence destination satisfaction. The author also discusses theoretical and managerial implications of research findings for marketing the heritage globally.Keywords: heritage, destination loyalty, destination image, consumer travel experience, destination satisfaction, tourism
Procedia PDF Downloads 4445970 Industrial Hemp Agronomy and Fibre Value Chain in Pakistan: Current Progress, Challenges, and Prospects
Authors: Saddam Hussain, Ghadeer Mohsen Albadrani
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Pakistan is one of the most vulnerable countries to climate change. Being a country where 23% of the country’s GDP relies on agriculture, this is a serious cause of concern. Introducing industrial hemp in Pakistan can help build climate resilience in the agricultural sector of the country, as hemp has recently emerged as a sustainable, eco-friendly, resource-efficient, and climate-resilient crop globally. Hemp has the potential to absorb huge amounts of CO₂, nourish the soil, and be used to create various biodegradable and eco-friendly products. Hemp is twice as effective as trees at absorbing and locking up carbon, with 1 hectare (2.5 acres) of hemp reckoned to absorb 8 to 22 tonnes of CO₂ a year, more than any woodland. Along with its high carbon-sequestration ability, it produces higher biomass and can be successfully grown as a cover crop. Hemp can grow in almost all soil conditions and does not require pesticides. It has fast-growing qualities and needs only 120 days to be ready for harvest. Compared with cotton, hemp requires 50% less water to grow and can produce three times higher fiber yield with a lower ecological footprint. Recently, the Government of Pakistan has allowed the cultivation of industrial hemp for industrial and medicinal purposes, making it possible for hemp to be reinserted into the country’s economy. Pakistan’s agro-climatic and edaphic conditions are well-suitable to produce industrial hemp, and its cultivation can bring economic benefits to the country. Pakistan can enter global markets as a new exporter of hemp products. The production of hemp in Pakistan can be most exciting to the workforce, especially for farmers participating in hemp markets. The minimum production cost of hemp makes it affordable to small holding farmers, especially those who need their cropping system to be as highly sustainable as possible. Dr. Saddam Hussain is leading the first pilot project of Industrial Hemp in Pakistan. In the past three years, he has been able to recruit high-impact research grants on industrial hemp as Principal Investigator. He has already screened the non-toxic hemp genotypes, tested the adaptability of exotic material in various agroecological conditions, formulated the production agronomy, and successfully developed the complete value chain. He has developed prototypes (fabric, denim, knitwear) using hemp fibre in collaboration with industrial partners and has optimized the indigenous fibre processing techniques. In this lecture, Dr. Hussain will talk on hemp agronomy and its complete fibre value chain. He will discuss the current progress, and will highlight the major challenges and future research direction on hemp research.Keywords: industrial hemp, agricultural sustainability, agronomic evaluation, hemp value chain
Procedia PDF Downloads 805969 Enumerating Insect Biodiversity in the Himalayan Mountains of India in Context to Species Richness, Biogeographic Distribution, and Possible Gap Areas in Taxonomic Research
Authors: Kailash Chandra, Devanshu Gupta
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The Himalayan Mountains of India fall under two biogeographic zones Trans Himalaya (TH) and Himalaya and seven biotic provinces (TH-Ladakh Mountains, TH-Tibetan Plateau, TH-Sikkim, North-West Himalaya, West Himalaya, Central Himalaya, and East Himalaya). Because of the extreme environment and altitudinal variations, unique physiography, varied ecological conditions, and different vegetations, the Himalaya exhibit a rich assemblage of life, both flora, and fauna, further subjected to the impacts of climate change. To the authors’ best knowledge, there is no comprehensive account except for sporadic faunal investigations, to assess or interpret the insect diversity and their biogeographic distribution in Indian Himalaya (IH), one of the biodiversity hotspots. Therefore, in this paper, a compelling review of the extensive knowledge of insect diversity of IH is presented for the first time to the best of our knowledge. The inventory of the known insect species of IH was compiled from the exploration cum faunal-study data ready with the zoological survey of India, Kolkata as well as from the information published in the scientific literature till date. The species were listed with their valid names with their distribution in seven biotic provinces of IH. The insect fauna of IH represents about 38% of the identified insect diversity of India. The interpretation of data provided significant information in detecting possible gap areas in the taxonomic representation of different insect orders. Archaeognatha, Zygentoma, Ephemeroptera, Phasmida, Embioptera, Psocoptera, Phthiraptera, Strepsiptera, Megaloptera, Raphidioptera, Siphonaptera, and Mecoptera need revisions, and it is required to collect more samples from remote areas of the region. Scope for finding new taxa even in the most diverse orders, Coleoptera, Lepidoptera, Hymenoptera, Diptera, and Hemiptera cannot be overlooked. Exploration of cold deserts of Trans Himalaya and East Himalaya (Arunachal Pradesh) may result in a good number of new species from these regions. The most notable data was that many of the species recorded from Himalaya are still known from their type localities only, so there is an urgency to revisit and resurvey those collection localities for the evaluation of the status of those species. It is also required to assess and monitor the impact of climate change on the diversity of insects inhabiting in the fragile Himalayan ecosystem. DNA barcoding especially pests and biological control agents to solve the problems of identification in species complexes is also the need of the hour. In a nutshell, it can be concluded that the inventory of insects of this region is extensive but is far from final as every year hundreds of new species are described.Keywords: catalog, climate change, diversity, DNA barcoding
Procedia PDF Downloads 2155968 An Observation of Patient-Professional Communication in the Cambodian Dental Setting
Authors: Christina Tran, Lu Khoo, Andrea Waylen
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Introduction: The evolution of the dental consultation from paternalism to partnership has been well documented in developed Western countries. Great emphasis is now placed on the importance of empowering patients to make decisions regarding their care, obtaining informed consent, and maintaining patient privacy and confidentiality. With the majority of communication occurring non-verbally, clinicians often adopt behaviours which suggest an approachable and positive attitude. However, evidence indicates that in Asia, a paternalistic model may be favored in medicine. The power imbalance occurring in doctor-patient relationships worldwide may be exacerbated by various factors in Southeast Asia: the strong hierarchical culture, and the large education gap between doctor and patient. Further insight into this matter can be gained by observing patient-dentist communication in Cambodia. The dentist:population ratio in Cambodia is approximately 1:33,000, with rural areas remaining extremely underserviced. We have carried out an observational study of communication in a voluntary dental clinic in Cambodia with the aim of describing whether the patient-dentist relationship follows a paternalistic or patient-centred model. Method: Over a period of two weeks, two clinicians provided dental care as part of a voluntary program in two Cambodian settings: a temporary, rural clinic and a permanent clinic in Phnom Penh. The clinicians independently recorded their experiences in diaries, making observations on the verbal and non-verbal communication between patients and staff. General observations such as the clinic environment were also made. The diaries were then compared and analyzed using a thematic approach. Results: The overall themes that emerged were regarding the clinic environment, verbal communication, and non-verbal communication. Regarding the clinic environment, the rural clinic was arranged in order to easily direct patients from one dentist to another, with little emphasis on continuous patient care. There was also little consideration for patient privacy: patients were often treated in the presence of many observers, including other waiting patients. However, the permanent clinic was structured to allow greater patient privacy, with continuous patient care occurring throughout the appointment. Regarding verbal communication, there was a strongly paternalistic approach to gaining consent and giving instruction. Patients rarely asked questions regarding their treatment, with dentists doing little to encourage patient involvement. Non-verbal communication between patients and dentists was generally paternalistic, with the dentist often addressing the supine patient from above. Patients often avoided making eye-contact, which may have indicated discomfort or lack of engagement. Both adult and paediatric patients rarely raised verbal concerns regarding pain during treatment, despite displaying non-verbal signs of experiencing pain. Anxious paediatric patients were sometimes managed with physical restraint by their mothers to facilitate treatment. Conclusion: Patient-professional communication in the Cambodian dental setting was observed to be generally paternalistic in nature, although more patient-centred aspects were observed in the established, urban setting. However, it should be noted that these observations are subjective in nature, and that the patients’ actual perceptions of their communication experience were unexplored. Further observations in variety of dental settings in Cambodia are needed before any definitive conclusions can be made.Keywords: patient-dentist communication, paternalism, patient-centered, non-verbal communication
Procedia PDF Downloads 1225967 Co-pyrolysis of Sludge and Kaolin/Zeolite to Stabilize Heavy Metals
Authors: Qian Li, Zhaoping Zhong
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Sewage sludge, a typical solid waste, has inevitably been produced in enormous quantities in China. Still worse, the amount of sewage sludge produced has been increasing due to rapid economic development and urbanization. Compared to the conventional method to treat sewage sludge, pyrolysis has been considered an economic and ecological technology because it can significantly reduce the sludge volume, completely kill pathogens, and produce valuable solid, gas, and liquid products. However, the large-scale utilization of sludge biochar has been limited due to the considerable risk posed by heavy metals in the sludge. Heavy metals enriched in pyrolytic biochar could be divided into exchangeable, reducible, oxidizable, and residual forms. The residual form of heavy metals is the most stable and cannot be used by organisms. Kaolin and zeolite are environmentally friendly inorganic minerals with a high surface area and heat resistance characteristics. So, they exhibit the enormous potential to immobilize heavy metals. In order to reduce the risk of leaching heavy metals in the pyrolysis biochar, this study pyrolyzed sewage sludge mixed with kaolin/zeolite in a small rotary kiln. The influences of additives and pyrolysis temperature on the leaching concentration and morphological transformation of heavy metals in pyrolysis biochar were investigated. The potential mechanism of stabilizing heavy metals in the co-pyrolysis of sludge blended with kaolin/zeolite was explained by scanning electron microscopy, X-ray diffraction, and specific surface area and porosity analysis. The European Community Bureau of Reference sequential extraction procedure has been applied to analyze the forms of heavy metals in sludge and pyrolysis biochar. All the concentrations of heavy metals were examined by flame atomic absorption spectrophotometry. Compared with the proportions of heavy metals associated with the F4 fraction in pyrolytic carbon prepared without additional agents, those in carbon obtained by co-pyrolysis of sludge and kaolin/zeolite increased. Increasing the additive dosage could improve the proportions of the stable fraction of various heavy metals in biochar. Kaolin exhibited a better effect on stabilizing heavy metals than zeolite. Aluminosilicate additives with excellent adsorption performance could capture more released heavy metals during sludge pyrolysis. Then heavy metal ions would react with the oxygen ions of additives to form silicate and aluminate, causing the conversion of heavy metals from unstable fractions (sulfate, chloride, etc.) to stable fractions (silicate, aluminate, etc.). This study reveals that the efficiency of stabilizing heavy metals depends on the formation of stable mineral compounds containing heavy metals in pyrolysis biochar.Keywords: co-pyrolysis, heavy metals, immobilization mechanism, sewage sludge
Procedia PDF Downloads 665966 Confirmatory Analysis of Externalizing Issue Validity from an Adolescent Sample
Authors: Zhidong Zhang, Zhi-Chao Zhang
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This study investigated the structural validity of externalizing issues of Achenbach System of Empirically Based Assessment (ASEBA) via a Chinese sample. The externalizing problems consist of two sub-problems: rule-breaking behavior and aggressive behavior. The rule-breaking behavior consists of 17 items, and aggressive behavior consists of 18 items. The factor analysis model was used to examine the structure validity. For the rule breaking behavior, at the first step, the most items weighted with component 2. After the rotation, there was a clear weight on both component 1 and 2. For the aggressive behavior, at the first step, there was no clear picture about the components. After the rotation, two clusters of items were closer to component 1 and 2 respectively. It seemed that both rule breaking behavior issue and aggressive behavior issue suggested two components. Further studies should be done to examine both samples and structures of externalizing problems.Keywords: confirmatory analysis, externalizing issue, structural validity, varimax rotations
Procedia PDF Downloads 4335965 Phytopathology Prediction in Dry Soil Using Artificial Neural Networks Modeling
Authors: F. Allag, S. Bouharati, M. Belmahdi, R. Zegadi
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The rapid expansion of deserts in recent decades as a result of human actions combined with climatic changes has highlighted the necessity to understand biological processes in arid environments. Whereas physical processes and the biology of flora and fauna have been relatively well studied in marginally used arid areas, knowledge of desert soil micro-organisms remains fragmentary. The objective of this study is to conduct a diversity analysis of bacterial communities in unvegetated arid soils. Several biological phenomena in hot deserts related to microbial populations and the potential use of micro-organisms for restoring hot desert environments. Dry land ecosystems have a highly heterogeneous distribution of resources, with greater nutrient concentrations and microbial densities occurring in vegetated than in bare soils. In this work, we found it useful to use techniques of artificial intelligence in their treatment especially artificial neural networks (ANN). The use of the ANN model, demonstrate his capability for addressing the complex problems of uncertainty data.Keywords: desert soil, climatic changes, bacteria, vegetation, artificial neural networks
Procedia PDF Downloads 3945964 The Interaction of Adjacent Defects and the Effect on the Failure Pressure of the Corroded Pipeline
Authors: W. Wang, Y. Zhang, J. Shuai, Z. Lv
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The interaction between defects has an essential influence on the bearing capacity of pipelines. This work developed the finite element model of pipelines containing adjacent defects, which includes longitudinally aligned, circumferentially aligned, and diagonally aligned defects. The relationships between spacing and geometries of defects and the failure pressure of pipelines, and the interaction between defects are investigated. The results show that the orientation of defects is an influential factor in the failure pressure of the pipeline. The influence of defect spacing on the failure pressure of the pipeline is non-linear, and the relationship presents different trends depending on the orientation of defects. The increase of defect geometry will weaken the failure pressure of the pipeline, and for the interaction between defects, the increase of defect depth will enhance it, and the increase of defect length will weaken it. According to the research on the interaction rule between defects with different orientations, the interacting coefficients under different orientations of defects are compared. It is determined that the diagonally aligned defects with the overlap of longitudinal projections are the most obvious arrangement of interaction between defects, and the limited distance of interaction between defects is proposed.Keywords: pipeline, adjacent defects, interaction between defects, failure pressure
Procedia PDF Downloads 2215963 An Investigation on Material Removal Rate of EDM Process: A Response Surface Methodology Approach
Authors: Azhar Equbal, Anoop Kumar Sood, M. Asif Equbal, M. Israr Equbal
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In the present work response surface methodology (RSM) based central composite design (CCD) is used for analyzing the electrical discharge machining (EDM) process. For experimentation, mild steel is selected as work piece and copper is used as electrode. Three machining parameters namely current (I), spark on time (Ton) and spark off time (Toff) are selected as the input variables. The output or response chosen is material removal rate (MRR) which is to be maximized. To reduce the number of runs face centered central composite design (FCCCD) was used. ANOVA was used to determine the significance of parameter and interactions. The suitability of model is tested using Anderson darling (AD) plot. The results conclude that different parameters considered i.e. current, pulse on and pulse off time; all have dominant effect on the MRR. At last, the optimized parameter setting for maximizing MRR is found through main effect plot analysis.Keywords: EDM, electrode, MRR, RSM, ANOVA
Procedia PDF Downloads 3055962 Combining an Optimized Closed Principal Curve-Based Method and Evolutionary Neural Network for Ultrasound Prostate Segmentation
Authors: Tao Peng, Jing Zhao, Yanqing Xu, Jing Cai
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Due to missing/ambiguous boundaries between the prostate and neighboring structures, the presence of shadow artifacts, as well as the large variability in prostate shapes, ultrasound prostate segmentation is challenging. To handle these issues, this paper develops a hybrid method for ultrasound prostate segmentation by combining an optimized closed principal curve-based method and the evolutionary neural network; the former can fit curves with great curvature and generate a contour composed of line segments connected by sorted vertices, and the latter is used to express an appropriate map function (represented by parameters of evolutionary neural network) for generating the smooth prostate contour to match the ground truth contour. Both qualitative and quantitative experimental results showed that our proposed method obtains accurate and robust performances.Keywords: ultrasound prostate segmentation, optimized closed polygonal segment method, evolutionary neural network, smooth mathematical model, principal curve
Procedia PDF Downloads 2005961 Numerical Study of the Influence of the Primary Stream Pressure on the Performance of the Ejector Refrigeration System Based on Heat Exchanger Modeling
Authors: Elhameh Narimani, Mikhail Sorin, Philippe Micheau, Hakim Nesreddine
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Numerical models of the heat exchangers in ejector refrigeration system (ERS) were developed and validated with the experimental data. The models were based on the switched heat exchangers model using the moving boundary method, which were capable of estimating the zones’ lengths, the outlet temperatures of both sides and the heat loads at various experimental points. The developed models were utilized to investigate the influence of the primary flow pressure on the performance of an R245fa ERS based on its coefficient of performance (COP) and exergy efficiency. It was illustrated numerically and proved experimentally that increasing the primary flow pressure slightly reduces the COP while the exergy efficiency goes through a maximum before decreasing.Keywords: Coefficient of Performance, COP, Ejector Refrigeration System, ERS, exergy efficiency (ηII), heat exchangers modeling, moving boundary method
Procedia PDF Downloads 2015960 Estimation of Fouling in a Cross-Flow Heat Exchanger Using Artificial Neural Network Approach
Authors: Rania Jradi, Christophe Marvillet, Mohamed Razak Jeday
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One of the most frequently encountered problems in industrial heat exchangers is fouling, which degrades the thermal and hydraulic performances of these types of equipment, leading thus to failure if undetected. And it occurs due to the accumulation of undesired material on the heat transfer surface. So, it is necessary to know about the heat exchanger fouling dynamics to plan mitigation strategies, ensuring a sustainable and safe operation. This paper proposes an Artificial Neural Network (ANN) approach to estimate the fouling resistance in a cross-flow heat exchanger by the collection of the operating data of the phosphoric acid concentration loop. The operating data of 361 was used to validate the proposed model. The ANN attains AARD= 0.048%, MSE= 1.811x10⁻¹¹, RMSE= 4.256x 10⁻⁶ and r²=99.5 % of accuracy which confirms that it is a credible and valuable approach for industrialists and technologists who are faced with the drawbacks of fouling in heat exchangers.Keywords: cross-flow heat exchanger, fouling, estimation, phosphoric acid concentration loop, artificial neural network approach
Procedia PDF Downloads 1975959 Peeling Behavior of Thin Elastic Films Bonded to Rigid Substrate of Random Surface Topology
Authors: Ravinu Garg, Naresh V. Datla
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We study the fracture mechanics of peeling of thin films perfectly bonded to a rigid substrate of any random surface topology using an analytical formulation. A generalized theoretical model has been developed to determine the peel strength of thin elastic films. It is demonstrated that an improvement in the peel strength can be achieved by modifying the surface characteristics of the rigid substrate. Characterization study has been performed to analyze the effect of different parameters on effective peel force from the rigid surface. Different surface profiles such as circular and sinusoidal has been considered to demonstrate the bonding characteristics of film-substrate interface. Condition for the instability in the debonding of the film is analyzed, where the localized self-debonding arises depending upon the film and surface characteristics. This study is towards improved adhesion strength of thin films to rigid substrate using different textured surfaces.Keywords: debonding, fracture mechanics, peel test, thin film adhesion
Procedia PDF Downloads 4485958 The Layered Transition Metal Dichalcogenides as Materials for Storage Clean Energy: Ab initio Investigations
Authors: S. Meziane, H. I. Faraoun, C. Esling
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Transition metal dichalcogenides have potential applications in power generation devices that convert waste heat into electric current by the so-called Seebeck and Hall effects thus providing an alternative energy technology to reduce the dependence on traditional fossil fuels. In this study, the thermoelectric properties of 1T and 2HTaX2 (X= S or Se) dichalcogenide superconductors have been computed using the semi-classical Boltzmann theory. Technologically, the task is to fabricate suitable materials with high efficiency. It is found that 2HTaS2 possesses the largest value of figure of merit ZT= 1.27 at 175 K. From a scientific point of view, we aim to model the underlying materials properties and in particular the transport phenomena as mediated by electrons and lattice vibrations responsible for superconductivity, Charge Density Waves (CDW) and metal/insulator transitions as function of temperature. The goal of the present work is to develop an understanding of the superconductivity of these selected materials using the transport properties at the fundamental level.Keywords: Ab initio, High efficiency, Power generation devices, Transition metal dichalcogenides
Procedia PDF Downloads 1975957 Analysis of Exponential Distribution under Step Stress Partially Accelerated Life Testing Plan Using Adaptive Type-I Hybrid Progressive Censoring Schemes with Competing Risks Data
Authors: Ahmadur Rahman, Showkat Ahmad Lone, Ariful Islam
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In this article, we have estimated the parameters for the failure times of units based on the sampling technique adaptive type-I progressive hybrid censoring under the step-stress partially accelerated life tests for competing risk. The failure times of the units are assumed to follow an exponential distribution. Maximum likelihood estimation technique is used to estimate the unknown parameters of the distribution and tampered coefficient. Confidence interval also obtained for the parameters. A simulation study is performed by using Monte Carlo Simulation method to check the authenticity of the model and its assumptions.Keywords: adaptive type-I hybrid progressive censoring, competing risks, exponential distribution, simulation, step-stress partially accelerated life tests
Procedia PDF Downloads 3435956 Assessment of Memetic and Genetic Algorithm for a Flexible Integrated Logistics Network
Authors: E. Behmanesh, J. Pannek
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The distribution-allocation problem is known as one of the most comprehensive strategic decision. In real-world cases, it is impossible to solve a distribution-allocation problem in traditional ways with acceptable time. Hence researchers develop efficient non-traditional techniques for the large-term operation of the whole supply chain. These techniques provide near-optimal solutions particularly for large scales test problems. This paper, presents an integrated supply chain model which is flexible in the delivery path. As the solution methodology, we apply a memetic algorithm with a novelty in population presentation. To illustrate the performance of the proposed memetic algorithm, LINGO optimization software serves as a comparison basis for small size problems. In large size cases that we are dealing with in the real world, the Genetic algorithm as the second metaheuristic algorithm is considered to compare the results and show the efficiency of the memetic algorithm.Keywords: integrated logistics network, flexible path, memetic algorithm, genetic algorithm
Procedia PDF Downloads 3745955 Simulation Study of the Microwave Heating of the Hematite and Coal Mixture
Authors: Prasenjit Singha, Sunil Yadav, Soumya Ranjan Mohantry, Ajay Kumar Shukla
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Temperature distribution in the hematite ore mixed with 7.5% coal was predicted by solving a 1-D heat conduction equation using an implicit finite difference approach. In this work, it was considered a square slab of 20 cm x 20 cm, which assumed the coal to be uniformly mixed with hematite ore. It was solved the equations with the use of MATLAB 2018a software. Heat transfer effects in this 1D dimensional slab convective and the radiative boundary conditions are also considered. Temperature distribution obtained inside hematite slab by considering microwave heating time, thermal conductivity, heat capacity, carbon percentage, sample dimensions, and many other factors such as penetration depth, permittivity, and permeability of coal and hematite ore mixtures. The resulting temperature profile can be used as a guiding tool for optimizing the microwave-assisted carbothermal reduction process of hematite slab was extended to other dimensions as well, viz., 1 cm x 1 cm, 5 cm x 5 cm, 10 cm x 10 cm, 20 cm x 20 cm. The model predictions are in good agreement with experimental results.Keywords: hematite ore, coal, microwave processing, heat transfer, implicit method, temperature distribution
Procedia PDF Downloads 1685954 Economic and Environmental Benefits of the Indium Recycling from the Waste Liquid Crystal Displays in China
Authors: Wu Yufeng, Gu Yifan, Wang Hengguang, Gongyu, Zuo Tieyong
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Indium is one the scarce resources which can be only used less than 30 years, and more than 70% of the indium is used for the production of the LCD. The benefit of recycling Indium from waste LCD is large. Take the LCD-TV for example, the yield of which was close to 90 million units in 2010. If it was available to recycle the indium effectively, the yield of the secondary-indium could reach up to 110 metric ton, which accounted for one third of the primary indium production in China. And compared with the dispersion and long process extraction of the primary indium resources, secondary indium concentrates in the waste LCD, the exploitation has great economic and environmental benefits. However, the potential benefits were indefinite, resulting in China’s government did not pay enough attention to the indium recycling industry. In our study, an estimation model was constructed to analyze the potential of the indium in the waste LCD. The different types of LCD were detected to find out the content of indium. Then, the potential of the indium in the waste LCD was estimated in China. Furthermore, the pollution emissions of the product process of the primary and secondary indium was analyzed respectively to calculate the economic and environmental benefits of the indium recycling from the waste LCD in China.Keywords: indium recycling, waste liquid crystal displays, benefits, China
Procedia PDF Downloads 4255953 Water Balance Components under Climate Change in Croatia
Authors: Jelena Bašić, Višnjica Vučetić, Mislav Anić, Tomislav Bašić
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Lack of precipitation combined with high temperatures causes great damage to the agriculture and economy in Croatia. Therefore, it is important to understand water circulation and balance. We decided to gain a better insight into the spatial distribution of water balance components (WBC) and their long-term changes in Croatia. WBC are precipitation (P), potential evapotranspiration (PET), actual evapotranspiration (ET), soil moisture content (S), runoff (RO), recharge (R), and soil moisture loss (L). Since measurements of the mentioned components in Croatia are very rare, the Palmer model has been applied to estimate them. We refined method by setting into the account the corrective factor to include influence effects of the wind as well as a maximum soil capacity for specific soil types. We will present one hundred years’ time series of PET and ET showing the trends at few meteorological stations and a comparison of components of two climatological periods. The meteorological data from 109 stations have been used for the spatial distribution map of the WBC of Croatia.Keywords: croatia, long-term trends, the palmer method, water balance components
Procedia PDF Downloads 1415952 PWM Based Control of Dstatcom for Voltage Sag, Swell Mitigation in Distribution Systems
Authors: A. Assif
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This paper presents the modeling of a prototype distribution static compensator (D-STATCOM) for voltage sag and swell mitigation in an unbalanced distribution system. Here the concept that an inverter can be used as generalized impedance converter to realize either inductive or capacitive reactance has been used to mitigate power quality issues of distribution networks. The D-STATCOM is here supposed to replace the widely used StaticVar Compensator (SVC). The scheme is based on the Voltage Source Converter (VSC) principle. In this model PWM based control scheme has been implemented to control the electronic valves of VSC. Phase shift control Algorithm method is used for converter control. The D-STATCOM injects a current into the system to mitigate the voltage sags. In this paper the modeling of D¬STATCOM has been designed using MATLAB SIMULINIC. Accordingly, simulations are first carried out to illustrate the use of D-STATCOM in mitigating voltage sag in a distribution system. Simulation results prove that the D-STATCOM is capable of mitigating voltage sag as well as improving power quality of a system.Keywords: D-STATCOM, voltage sag, voltage source converter (VSC), phase shift control
Procedia PDF Downloads 3435951 Early Detection of Lymphedema in Post-Surgery Oncology Patients
Authors: Sneha Noble, Rahul Krishnan, Uma G., D. K. Vijaykumar
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Breast-Cancer related Lymphedema is a major problem that affects many women. Lymphedema is the swelling that generally occurs in the arms or legs caused by the removal of or damage to lymph nodes as a part of cancer treatment. Treating it at the earliest possible stage is the best way to manage the condition and prevent it from leading to pain, recurrent infection, reduced mobility, and impaired function. So, this project aims to focus on the multi-modal approaches to identify the risks of Lymphedema in post-surgical oncology patients and prevent it at the earliest. The Kinect IR Sensor is utilized to capture the images of the body and after image processing techniques, the region of interest is obtained. Then, performing the voxelization method will provide volume measurements in pre-operative and post-operative periods in patients. The formation of a mathematical model will help in the comparison of values. Clinical pathological data of patients will be investigated to assess the factors responsible for the development of lymphedema and its risks.Keywords: Kinect IR sensor, Lymphedema, voxelization, lymph nodes
Procedia PDF Downloads 1385950 Defective Autophagy Disturbs Neural Migration and Network Activity in hiPSC-Derived Cockayne Syndrome B Disease Models
Authors: Julia Kapr, Andrea Rossi, Haribaskar Ramachandran, Marius Pollet, Ilka Egger, Selina Dangeleit, Katharina Koch, Jean Krutmann, Ellen Fritsche
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It is widely acknowledged that animal models do not always represent human disease. Especially human brain development is difficult to model in animals due to a variety of structural and functional species-specificities. This causes significant discrepancies between predicted and apparent drug efficacies in clinical trials and their subsequent failure. Emerging alternatives based on 3D in vitro approaches, such as human brain spheres or organoids, may in the future reduce and ultimately replace animal models. Here, we present a human induced pluripotent stem cell (hiPSC)-based 3D neural in a vitro disease model for the Cockayne Syndrome B (CSB). CSB is a rare hereditary disease and is accompanied by severe neurologic defects, such as microcephaly, ataxia and intellectual disability, with currently no treatment options. Therefore, the aim of this study is to investigate the molecular and cellular defects found in neural hiPSC-derived CSB models. Understanding the underlying pathology of CSB enables the development of treatment options. The two CSB models used in this study comprise a patient-derived hiPSC line and its isogenic control as well as a CSB-deficient cell line based on a healthy hiPSC line (IMR90-4) background thereby excluding genetic background-related effects. Neurally induced and differentiated brain sphere cultures were characterized via RNA Sequencing, western blot (WB), immunocytochemistry (ICC) and multielectrode arrays (MEAs). CSB-deficiency leads to an altered gene expression of markers for autophagy, focal adhesion and neural network formation. Cell migration was significantly reduced and electrical activity was significantly increased in the disease cell lines. These data hint that the cellular pathologies is possibly underlying CSB. By induction of autophagy, the migration phenotype could be partially rescued, suggesting a crucial role of disturbed autophagy in defective neural migration of the disease lines. Altered autophagy may also lead to inefficient mitophagy. Accordingly, disease cell lines were shown to have a lower mitochondrial base activity and a higher susceptibility to mitochondrial stress induced by rotenone. Since mitochondria play an important role in neurotransmitter cycling, we suggest that defective mitochondria may lead to altered electrical activity in the disease cell lines. Failure to clear the defective mitochondria by mitophagy and thus missing initiation cues for new mitochondrial production could potentiate this problem. With our data, we aim at establishing a disease adverse outcome pathway (AOP), thereby adding to the in-depth understanding of this multi-faced disorder and subsequently contributing to alternative drug development.Keywords: autophagy, disease modeling, in vitro, pluripotent stem cells
Procedia PDF Downloads 1205949 United against Drugs: Divergent Counternarcotic Strategies of US Government Agencies in Afghanistan
Authors: Anthony George Armiger II
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This paper focuses on the counternarcotic strategies of US government agencies in Afghanistan from 2001-2014. Despite a heavy US presence in the country, Afghanistan currently accounts for 80% of opium production worldwide and remains a key contributor to the global drug market. This paper argues that the divergent counternarcotic strategies of various US government agencies on the ground in Afghanistan are a product of the organizational differences amongst those agencies and that those differences can challenge the implementation of counternarcotics policies in Afghanistan. To gain a more in-depth perspective, this paper analyzes the counternarcotic strategies of two US government agencies in Afghanistan; the United States Department of Defense (DoD) and the Drug Enforcement Administration (DEA). Utilizing the framework of the organizational behavior model of organizational theory, this paper will highlight the varying organizational interests, opinions, standard operating procedures, and routines of both of the government agencies. The paper concludes with implications on counternarcotics, as well as the counterinsurgency in Afghanistan and provides recommendations for future research on foreign policy and counternarcotics.Keywords: Afghanistan, drug policy, organizational theory, United States foreign policy
Procedia PDF Downloads 3765948 Microstructure and Excess Conductivity of Bulk, Ag-Added FeSe Superconductors
Authors: Michael Koblischka, Yassine Slimani, Thomas Karwoth, Anjela Koblischka-Veneva, Essia Hannachi
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On bulk FeSe superconductors containing different additions of Ag, a thorough investigation of the microstructures was performed using optical microscopy, SEM and TEM. The electrical resistivity was measured using four-point measurements in the temperature range 2 K ≤ T ≤ 150 K. The data obtained are analyzed in the framework of the excess conductivity approach using the Aslamazov-Larkin (AL) model. The investigated samples comprised of five distinct fluctuation regimes, namely short-wave (SWF), onedimensional (1D), two-dimensional (2D), three-dimensional (3D), and critical (CR) fluctuation regimes. The coherence length along the c-axis at zero-temperature (ξc(0)), the lower and upper critical magnetic fields (Bc1 and Bc2), the critical current density (Jc) and numerous other superconducting parameters were estimated with respect to the Ag content in the samples. The data reveal a reduction of the resistivity and a strong decrease of ξc(0) when doping the 11-samples with silver. The optimum content of the Ag-addition is found at 4 wt.-% Ag, yielding the highest critical current density.Keywords: iron-based superconductors, FeSe, Ag-addition, excess conductivity, microstructure
Procedia PDF Downloads 145