Search results for: cytotoxicity study
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 50469

Search results for: cytotoxicity study

18489 Investigation of Software Integration for Simulations of Buoyancy-Driven Heat Transfer in a Vehicle Underhood during Thermal Soak

Authors: R. Yuan, S. Sivasankaran, N. Dutta, K. Ebrahimi

Abstract:

This paper investigates the software capability and computer-aided engineering (CAE) method of modelling transient heat transfer process occurred in the vehicle underhood region during vehicle thermal soak phase. The heat retention from the soak period will be beneficial to the cold start with reduced friction loss for the second 14°C worldwide harmonized light-duty vehicle test procedure (WLTP) cycle, therefore provides benefits on both CO₂ emission reduction and fuel economy. When vehicle undergoes soak stage, the airflow and the associated convective heat transfer around and inside the engine bay is driven by the buoyancy effect. This effect along with thermal radiation and conduction are the key factors to the thermal simulation of the engine bay to obtain the accurate fluids and metal temperature cool-down trajectories and to predict the temperatures at the end of the soak period. Method development has been investigated in this study on a light-duty passenger vehicle using coupled aerodynamic-heat transfer thermal transient modelling method for the full vehicle under 9 hours of thermal soak. The 3D underhood flow dynamics were solved inherently transient by the Lattice-Boltzmann Method (LBM) method using the PowerFlow software. This was further coupled with heat transfer modelling using the PowerTHERM software provided by Exa Corporation. The particle-based LBM method was capable of accurately handling extremely complicated transient flow behavior on complex surface geometries. The detailed thermal modelling, including heat conduction, radiation, and buoyancy-driven heat convection, were integrated solved by PowerTHERM. The 9 hours cool-down period was simulated and compared with the vehicle testing data of the key fluid (coolant, oil) and metal temperatures. The developed CAE method was able to predict the cool-down behaviour of the key fluids and components in agreement with the experimental data and also visualised the air leakage paths and thermal retention around the engine bay. The cool-down trajectories of the key components obtained for the 9 hours thermal soak period provide vital information and a basis for the further development of reduced-order modelling studies in future work. This allows a fast-running model to be developed and be further imbedded with the holistic study of vehicle energy modelling and thermal management. It is also found that the buoyancy effect plays an important part at the first stage of the 9 hours soak and the flow development during this stage is vital to accurately predict the heat transfer coefficients for the heat retention modelling. The developed method has demonstrated the software integration for simulating buoyancy-driven heat transfer in a vehicle underhood region during thermal soak with satisfying accuracy and efficient computing time. The CAE method developed will allow integration of the design of engine encapsulations for improving fuel consumption and reducing CO₂ emissions in a timely and robust manner, aiding the development of low-carbon transport technologies.

Keywords: ATCT/WLTC driving cycle, buoyancy-driven heat transfer, CAE method, heat retention, underhood modeling, vehicle thermal soak

Procedia PDF Downloads 155
18488 A Methodology of Testing Beam to Column Connection under Lateral Impact Load

Authors: A. Al-Rifaie, Z. W. Guan, S. W. Jones

Abstract:

Beam to column connection can be considered as the most important structural part that affects the response of buildings to progressive collapse. However, many studies were conducted to investigate the beam to column connection under accidental loads such as fire, blast and impact load to investigate the connection response. The study is a part of a PhD plan to investigate different types of connections under lateral impact load. The conventional test setups, such as cruciform setup, were designed to apply shear forces and bending moment on the connection, whilst, in the lateral impact case, the connection is subjected to combined tension and moment. Hence, a review is presented to introduce the previous test setup that is used to investigate the connection behaviour. Then, the design and fabrication of the novel test setup is presented. Finally, some trial test results to investigate the efficiency of the proposed setup are discussed. The final results indicate that the setup was efficient in terms of the simplicity and strength.

Keywords: connections, impact load, drop hammer, testing methods

Procedia PDF Downloads 300
18487 Vascular Targeted Photodynamic Therapy Monitored by Real-Time Laser Speckle Imaging

Authors: Ruth Goldschmidt, Vyacheslav Kalchenko, Lilah Agemy, Rachel Elmoalem, Avigdor Scherz

Abstract:

Vascular Targeted Photodynamic therapy (VTP) is a new modality for selective cancer treatment that leads to the complete tumor ablation. A photosensitizer, a bacteriochlorophyll derivative in our case, is first administered to the patient and followed by the illumination of the tumor area, by a near-IR laser for its photoactivation. The photoactivated drug releases reactive oxygen species (ROS) in the circulation, which reacts with blood cells and the endothelium leading to the occlusion of the blood vasculature. If the blood vessels are only partially closed, the tumor may recover, and cancer cells could survive. On the other hand, excessive treatment may lead to toxicity of healthy tissues nearby. Simultaneous VTP monitoring and image processing independent of the photoexcitation laser has not yet been reported, to our knowledge. Here we present a method for blood flow monitoring, using a real-time laser speckle imaging (RTLSI) in the tumor during VTP. We have synthesized over the years a library of bacteriochlorophyll derivatives, among them WST11 and STL-6014. Both are water soluble derivatives that are retained in the blood vasculature through their partial binding to HSA. WST11 has been approved in Mexico for VTP treatment of prostate cancer at a certain drug dose, and time/intensity of illumination. Application to other bacteriochlorophyll derivatives or other cancers may require different treatment parameters (such as light/drug administration). VTP parameters for STL-6014 are still under study. This new derivative mainly differs from WST11 by its lack of the central Palladium, and its conjugation to an Arg-Gly-Asp (RGD) sequence. RGD is a tumor-specific ligand that is used for targeting the necrotic tumor domains through its affinity to αVβ3 integrin receptors. This enables the study of cell-targeted VTP. We developed a special RTLSI module, based on Labview software environment for data processing. The new module enables to acquire raw laser speckle images and calculate the values of the laser temporal statistics of time-integrated speckles in real time, without additional off-line processing. Using RTLSI, we could monitor the tumor’s blood flow following VTP in a CT26 colon carcinoma ear model. VTP with WST11 induced an immediate slow down of the blood flow within the tumor and a complete final flow arrest, after some sporadic reperfusions. If the irradiation continued further, the blood flow stopped also in the blood vessels of the surrounding healthy tissue. This emphasizes the significance of light dose control. Using our RTLSI system, we could prevent any additional healthy tissue damage by controlling the illumination time and restrict blood flow arrest within the tumor only. In addition, we found that VTP with STL-6014 was the most effective when the photoactivation was conducted 4h post-injection, in terms of tumor ablation success in-vivo and blood vessel flow arrest. In conclusion, RTSLI application should allow to optimize VTP efficacy vs. toxicity in both the preclinical and clinical arenas.

Keywords: blood vessel occlusion, cancer treatment, photodynamic therapy, real time imaging

Procedia PDF Downloads 227
18486 Financial Portfolio Optimization in Electricity Markets: Evaluation via Sharpe Ratio

Authors: F. Gökgöz, M. E. Atmaca

Abstract:

Electricity plays an indispensable role in human life and the economy. It is a unique product or service that must be balanced instantaneously, as electricity is not stored, generation and consumption should be proportional. Effective and efficient use of electricity is very important not only for society, but also for the environment. A competitive electricity market is one of the best ways to provide a suitable platform for effective and efficient use of electricity. On the other hand, it carries some risks that should be carefully managed by the market players. Risk management is an essential part in market players’ decision making. In this paper, risk management through diversification is applied with the help of Markowitz’s Mean-variance, Down-side and Semi-variance methods for a case study. Performance of optimal electricity sale solutions are measured and evaluated via Sharpe-Ratio, and the optimal portfolio solutions are improved. Two years of historical weekdays’ price data of the Turkish Day Ahead Market are used to demonstrate the approach.

Keywords: electricity market, portfolio optimization, risk management in electricity market, sharpe ratio

Procedia PDF Downloads 367
18485 Engineering Review of Recycled Concrete Production for Structural and Non-Structural Applications (Green Concrete)

Authors: Hadi Rouhi Belvirdi

Abstract:

With the increasing demand for sustainable development, recycled materials are receiving more attention in construction projects. To promote sustainable development, this review article evaluates the feasibility of using recycled concrete in construction projects from an economic and environmental perspective. The results show that making concrete using recycled concrete is a suitable strategy for sustainable development. A complete examination of the physical and chemical properties of these recycled materials also provides important information about their suitability for use in the construction industry. Most of the studies do not show surprising results of the compressive or bending strength of these materials, and only the aspect of sustainable development of these materials is of interest. Their application can be investigated more in masonry and joinery works, but among them, some studies sometimes obtained more compressive and bending strength than the control sample, which can be used in concrete structures. Most of the cases introduced and discussed in this study can be implemented and help the country and the people of Iran preserve the environment and discuss sustainable development.

Keywords: environmental recycling, sustainable development, recycled materials, construction management

Procedia PDF Downloads 33
18484 Synthesis, Characterization, and Properties Study of New Magnetic Materials

Authors: Messai Amel, Badis Zakaria, Benali-Cherif Nourredine, Dominique Luneaub

Abstract:

We are interested in molecular polymetallic species having high spin and nuclearities in relation to the field of so call single-molecule magnets (SMMs). The goal is to find a way to synthesis metal clusters which may have application in magnetism and nano sciences. With this purpose, we decided to investigate the coordination chemistry of the Schiff base. Along this way we were able to create cubane-like complexes and elaborate new Single Molecule-Magnets. The idea was to use Schiff base ligands and different metals to generate high nuclear complexes. Complexation of Shiff base with copper (II) has been investigated. Tetra nuclear complex with a cubane like core have been synthesized with (Sciff base), with the same base and cobalt (II) we obtain an other single magnetic complex completely different. In this presentation, we report the synthesis, crystal structure and magnetic properties of the tetranuclear compound (Cu4 L4), and the tetranuclear compound. (Co4L4)

Keywords: cluster-assembled materials, magnetic compounds, Sciff base, cupper, cobalt

Procedia PDF Downloads 453
18483 Investigation of the Decisive Factors on the Slump Loss: A Case Study of Cement Factors (Portland Cement Type 2)

Authors: M. B. Ahmadi, A. A. Kaffash B., B. Mobaraki

Abstract:

Slump loss, which refers to the gradual reduction of workability and the amount of slump in fresh concrete over time, is one of the significant challenges in the ready-mixed concrete industry. Therefore, having accurate knowledge of the factors affecting slump loss is a crucial solution in this field. In this paper, an attempt was made to investigate the effect of cement produced by different units on the slump of concrete in a laboratory setting. For this purpose, 12 cement samples were prepared from 6 different production units. Physical and chemical tests were performed on the cement samples. Subsequently, a laboratory concrete mix with a slump of 13 ± 1 cm was prepared with each cement sample, and the slump was measured at 0, 15, 30, 45, and 60 minutes. Although the environmental factors, mix design specifications, and execution conditions—factors that significantly influence the slump loss trend—were constant in all 12 laboratory concrete mixes, the slump loss trends differed among them. These trends were categorized based on the results, and the relationship between the slump loss percentage in 60 minutes, the water-cement ratio, and the LOI and K2O values of different cements were introduced.

Keywords: concrete, slump loss, portland cement, efficiency

Procedia PDF Downloads 80
18482 Evaluation of Critical State Behavior of Granular Soil in Confined Compression Tests

Authors: Rabia Chaudhry, Andrew Dawson

Abstract:

Identification of steady/critical state of coarse granular soil is challenging at conventional pressures. This study examines the drained and undrained triaxial tests for large strains on loose to dense, uniformly graded, Leighton Buzzard Fraction A sand. The triaxial tests are conducted under controlled test conditions. The comparison of soil behavior on shear strength characteristics at different effective stresses has been studied at the medium to large strains levels and the uniqueness of the critical state was discussed. The test results showed that there were two steady/critical state lines for drained and undrained conditions at confining pressures less than 1000 kPa. A critical state friction angle is not constant and the overall scatter in the steady/critical state line for the tested sand is ±0.01 in terms of void ratio at stress levels less than 1000 kPa.

Keywords: critical state, stress strain behavior, fabric/structure, triaxial tests

Procedia PDF Downloads 413
18481 Preparation and Characterization of Cellulose Based Antimicrobial Food Packaging Materials

Authors: Memet Vezir Kahraman, Ferhat Sen

Abstract:

This study aimed to develop polyelectrolyte structured antimicrobial food packaging materials that do not contain any antimicrobial agents. Cationic hydroxyethyl cellulose was synthesized and characterized by Fourier Transform Infrared, carbon and proton Nuclear Magnetic Resonance spectroscopy. Its nitrogen content was determined by the Kjeldahl method. Polyelectrolyte structured antimicrobial food packaging materials were prepared using hydroxyethyl cellulose, cationic hydroxyethyl cellulose, and sodium alginate. Antimicrobial activity of materials was defined by inhibition zone method (disc diffusion method). Thermal stability of samples was evaluated by thermal gravimetric analysis and differential scanning calorimetry. Surface morphology of samples was investigated by scanning electron microscope. The obtained results prove that produced food packaging materials have good thermal and antimicrobial properties, and they can be used as food packaging material in many industries.

Keywords: antimicrobial food packaging, cationic hydroxyethyl cellulose, polyelectrolyte, sodium alginate

Procedia PDF Downloads 161
18480 A Large Dataset Imputation Approach Applied to Country Conflict Prediction Data

Authors: Benjamin Leiby, Darryl Ahner

Abstract:

This study demonstrates an alternative stochastic imputation approach for large datasets when preferred commercial packages struggle to iterate due to numerical problems. A large country conflict dataset motivates the search to impute missing values well over a common threshold of 20% missingness. The methodology capitalizes on correlation while using model residuals to provide the uncertainty in estimating unknown values. Examination of the methodology provides insight toward choosing linear or nonlinear modeling terms. Static tolerances common in most packages are replaced with tailorable tolerances that exploit residuals to fit each data element. The methodology evaluation includes observing computation time, model fit, and the comparison of known values to replaced values created through imputation. Overall, the country conflict dataset illustrates promise with modeling first-order interactions while presenting a need for further refinement that mimics predictive mean matching.

Keywords: correlation, country conflict, imputation, stochastic regression

Procedia PDF Downloads 121
18479 The Influence of Smart Tourism Applications on Memorable Tourism Experience in Bangkok, Thailand

Authors: Wikanda Boonma, Jang Hyunmi

Abstract:

Smart tourism applications (STAs) play an important role in tourism to enhance the quality tourism experience and add value to tourists with accurate information, better decision support, greater time-saving, and providing more personalized information to meet tourists’ expectations. This paper intends to develop and investigate the effect of smart tourism applications on memorable tourism experiences in enhancing tourist satisfaction and destination loyalty. Questionnaires were distributed to tourists who are traveling in Bangkok, Thailand. A structural equation method was used to find the relationship among smart tourism technology attributes, the perceived value of the STAs, memorable tourism experience, tourist satisfaction, and destination loyalty. The findings of this study provide insight into the critical role of smart tourism applications, which create chances for smart tourism development. Additionally, some theoretical and managerial implications were derived from the findings.

Keywords: smart tourism applications, memorable tourism experience, tourist satisfaction, destination loyalty

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18478 People’s Perception towards the ASEAN Economic Community (AEC)

Authors: Nopadol Burananuth

Abstract:

The purposes of this research paper were to study the relationship between the economic factor and political factor, the relationship between political and economic factor and social factor, and the effects of economic factor, political factor, and social factor to the people’s perception about ASEAN Economic Community (AEC). A total of 400 samples were selected from four sub-districts from Arunyaprathet District, Srakaow Province. Data analysis method included multiple regression analysis. The findings revealed that political factor depended on trade cooperation, transportation cooperation, and communication cooperation. Social factor was depended on disaster protection, terrorism protection, and international relations. In addition, the people’s perception of the AEC depended on disaster perception, terrorism protection, international relations, transportation cooperation, communication cooperation, interdependence, and labor movement.

Keywords: economic factors, perception, political factors, social factors

Procedia PDF Downloads 592
18477 Officinal Quality Assurance: Investigation near the Pharmacists Dispensary at Oran- Algeria

Authors: S. Boulenouar, A. Boukli Hacene, S. Brahmi

Abstract:

Quality is an old concept but which recently became omnipresent in the society. It is a pledge of the well done job and therefore the satisfaction of the customer. Now, dispensing pharmacies seem to be held away from this approach. Officinal staff is called to dispense drugs. However this essential function is rarely studied and taken into account. To contribute to the good use of medicines and to reduce the dangers, it is important to consider the dispensation of drugs practised in the pharmacies. It is a both descriptive and retrospective study .The descriptive part is to conduct a survey near to the dispensary pharmacists. The retrospective section concentrates on the analysis of medicine prescriptions dispensed to patients. Following the survey that we carried out near the pharmacists of dispensary of the town of Oran, it appears that in majority, they are not inclined, by themselves, to take up the challenge of quality at the dispensary. The approach requires time and a motivation that pharmacists do not have for the moment. Efforts are still needed on the part of pharmacists, but also of authorities and organizations in charge of quality in the dispensary. At the end of this work, it seems to us that the implementation of a quality approach is part of our reflection on the added value of the pharmacist of dispensary in the drug chain.

Keywords: customer satisfaction, dispensary, dispensing of the drug, quality approach

Procedia PDF Downloads 321
18476 Sustainability Adoption Barriers in Small and Mid-size Enterprises (SEMs)

Authors: L.Vaz, L. Ferreira, R. Aparício, J. Pedro, M. Franco

Abstract:

This article concerns a qualitative analysis, through an interview, regarding “Sustainability Adoption Barriers in SMEs.” To begin with, the article provides a state-of-the-art overview through fifty-seven articles initially extracted from the Scopus database. The articles were analyzed, and four main clusters emerged in the literature: 1) sustainability and small and medium-sized companies; 2) sustainable business models; 3) sustainability practices adoption procedures, and 4) adoption difficulties on sustainability practices. Utilizing interviews as a methodology, the article seeks to strengthen knowledge regarding sustainability practices, their barriers and the sustainable procedures adopted by SMEs in a Portuguese context. The results demonstrate that the literature agrees with this case study, where there are numerous sustainable practices, yet, due to financial, political, cultural, and technological factors, barriers emerge in the adoption process. By comparing the literature findings with the conducted interviews of interior Portuguese SMEs, this article develops a contribution to the scientific community through a captivating, intuitive and motivating way.

Keywords: barriers, practices, business model, green

Procedia PDF Downloads 186
18475 Investigation of Thermal Comfort Conditions of Vernacular Buildings Taking into Consideration Various Use Patterns: A Case Study

Authors: Christina Kalogirou

Abstract:

The main goal of this paper is to explore the thermal comfort conditions in traditional buildings during all seasons of the year taking into consideration various use patterns. For this purpose a dwelling of vernacular architecture is selected and data regarding the indoor and outdoor air and surface temperature as well as the relative humidity are collected. These measurements are conducted in situ during the period of a year. Also, this building is occupied periodically and a calendar of occupancy was kept (duration of residence, hours of heating system operation, hours of natural ventilation, etc.) in order to correlate the indoor conditions recorded with the use patterns via statistical analysis. Furthermore, the effect of the high thermal inertia of the stone masonry walls and the different orientation of the rooms is addressed. Thus, this paper concludes in some interesting results on the effect of the users in the indoor climate conditions in the case of buildings with high thermal inertia envelops.

Keywords: thermal comfort, in situ measurements, occupant behaviour, vernacular architecture

Procedia PDF Downloads 443
18474 Passenger Flow Characteristics of Seoul Metropolitan Subway Network

Authors: Kang Won Lee, Jung Won Lee

Abstract:

Characterizing the network flow is of fundamental importance to understand the complex dynamics of networks. And passenger flow characteristics of the subway network are very relevant for an effective transportation management in urban cities. In this study, passenger flow of Seoul metropolitan subway network is investigated and characterized through statistical analysis. Traditional betweenness centrality measure considers only topological structure of the network and ignores the transportation factors. This paper proposes a weighted betweenness centrality measure that incorporates monthly passenger flow volume. We apply the proposed measure on the Seoul metropolitan subway network involving 493 stations and 16 lines. Several interesting insights about the network are derived from the new measures. Using Kolmogorov-Smirnov test, we also find out that monthly passenger flow between any two stations follows a power-law distribution and other traffic characteristics such as congestion level and throughflow traffic follow exponential distribution.

Keywords: betweenness centrality, correlation coefficient, power-law distribution, Korea traffic DB

Procedia PDF Downloads 292
18473 A Survey on the Blockchain Smart Contract System: Security Strengths and Weaknesses

Authors: Malaw Ndiaye, Karim Konate

Abstract:

Smart contracts are computer protocols that facilitate, verify, and execute the negotiation or execution of a contract, or that render a contractual term unnecessary. Blockchain and smart contracts can be used to facilitate almost any financial transaction. Thanks to these smart contracts, the settlement of dividends and coupons could be automated. Smart contracts have become lucrative and profitable targets for attackers because they can hold a great amount of money. Smart contracts, although widely used in blockchain technology, are far from perfect due to security concerns. Since there are recent studies on smart contract security, none of them systematically study the strengths and weaknesses of smart contract security. Some have focused on an analysis of program-related vulnerabilities by providing a taxonomy of vulnerabilities. Other studies are responsible for listing the series of attacks linked to smart contracts. Although a series of attacks are listed, there is a lack of discussions and proposals on improving security. This survey takes stock of smart contract security from a more comprehensive perspective by correlating the level of vulnerability and systematic review of security levels in smart contracts.

Keywords: blockchain, Bitcoin, smart contract, criminal smart contract, security

Procedia PDF Downloads 169
18472 The Link between Money Market and Economic Growth in Nigeria: Vector Error Correction Model Approach

Authors: Uyi Kizito Ehigiamusoe

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The paper examines the impact of money market on economic growth in Nigeria using data for the period 1980-2012. Econometrics techniques such as Ordinary Least Squares Method, Johanson’s Co-integration Test and Vector Error Correction Model were used to examine both the long-run and short-run relationship. Evidence from the study suggest that though a long-run relationship exists between money market and economic growth, but the present state of the Nigerian money market is significantly and negatively related to economic growth. The link between the money market and the real sector of the economy remains very weak. This implies that the market is not yet developed enough to produce the needed growth that will propel the Nigerian economy because of several challenges. It was therefore recommended that government should create the appropriate macroeconomic policies, legal framework and sustain the present reforms with a view to developing the market so as to promote productive activities, investments, and ultimately economic growth.

Keywords: economic growth, investments, money market, money market challenges, money market instruments

Procedia PDF Downloads 347
18471 Development of an Improved Paradigm for the Tourism Sector in the Department of Huila, Colombia: A Theoretical and Empirical Approach

Authors: Laura N. Bolivar T.

Abstract:

The tourism importance for regional development is mainly highlighted by the collaborative, cooperating and competitive relationships of the involved agents. The fostering of associativity processes, in particular, the cluster approach emphasizes the beneficial outcomes from the concentration of enterprises, where innovation and entrepreneurship flourish and shape the dynamics for tourism empowerment. Considering the department of Huila, it is located in the south-west of Colombia and holds the biggest coffee production in the country, although it barely contributes to the national GDP. Hence, its economic development strategy is looking for more dynamism and Huila could be consolidated as a leading destination for cultural, ecological and heritage tourism, if at least the public policy making processes for the tourism management of La Tatacoa Desert, San Agustin Park and Bambuco’s National Festival, were implemented in a more efficient manner. In this order of ideas, this study attempts to address the potential restrictions and beneficial factors for the consolidation of the tourism sector of Huila-Colombia as a cluster and how could it impact its regional development. Therefore, a set of theoretical frameworks such as the Tourism Routes Approach, the Tourism Breeding Environment, the Community-based Tourism Method, among others, but also a collection of international experiences describing tourism clustering processes and most outstanding problematics, is analyzed to draw up learning points, structure of proceedings and success-driven factors to be contrasted with the local characteristics in Huila, as the region under study. This characterization involves primary and secondary information collection methods and comprises the South American and Colombian context together with the identification of involved actors and their roles, main interactions among them, major tourism products and their infrastructure, the visitors’ perspective on the situation and a recap of the related needs and benefits regarding the host community. Considering the umbrella concepts, the theoretical and the empirical approaches, and their comparison with the local specificities of the tourism sector in Huila, an array of shortcomings is analytically constructed and a series of guidelines are proposed as a way to overcome them and simultaneously, raise economic development and positively impact Huila’s well-being. This non-exhaustive bundle of guidelines is focused on fostering cooperating linkages in the actors’ network, dealing with Information and Communication Technologies’ innovations, reinforcing the supporting infrastructure, promoting the destinations considering the less known places as well, designing an information system enabling the tourism network to assess the situation based on reliable data, increasing competitiveness, developing participative public policy-making processes and empowering the host community about the touristic richness. According to this, cluster dynamics would drive the tourism sector to meet articulation and joint effort, then involved agents and local particularities would be adequately assisted to cope with the current changing environment of globalization and competition.

Keywords: innovative strategy, local development, network of tourism actors, tourism cluster

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18470 Development of Eco-friendly Materials Based on Micro-filled Resin: Process Study and Mixture Optimization

Authors: Chenine Halima, Ouinas Djamel, Bekki Hamed Essiddik

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The matrix is made up of resin mixed with fillers. However, with the growing demand to reduce CO2 emissions, the market is increasingly leaning toward eco-friendly materials. In this context, this research focuses on developing an environmentally friendly material, with or without sand, by following various stages using micro-filled resin. Three manufacturing techniques will be explored: infusion, RTM-Eco, and molding. The process begins with incorporating sand directly into the resin matrix, a critical step in creating this type of composite. To achieve this, two mixing methods will be tested: one by hand and the other using a mechanical mixer. The best method will be selected based on key criteria, such as achieving a uniform sand distribution and determining the optimal sand-to-resin ratio. The final material must meet specific requirements, including strong mechanical performance, high-temperature resistance, cost-efficiency, and outstanding durability against corrosion.

Keywords: micro-charging of sand particles, laminated composites, polymer, resin, corrosion

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18469 Hydrodynamic Behavior Study of Fast Mono Hull and Catamaran Vessels in Calm Waters Using Free Surface Flow Analysis

Authors: Mohammad Ali Badri, Pouya Molana, Amin Rezvanpour

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In this paper, planning catamaran and mono-hull vessels resistance and trim in calm waters were considered. Hydrodynamic analysis of fast mono-hull planning vessel was also investigated. In order to hull form geometry optimization, numerical methods of different parameters were used for this type of vessels. Hull material was selected in carbon fiber composite. Exact architectural aspects were specified and stability calculations were performed as well. Hydrodynamic calculations to extract the resistance force using semi-analytical methods and numerical modeling were carried out. Free surface numerical analysis of vessel in designed draft using finite volume method and double phase were evaluated and verified by experimental tests.

Keywords: fast vessel, hydrostatic and hydrodynamic optimization, free surface flow, computational fluid dynamics

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18468 Introduction of a Medicinal Plants Garden to Revitalize a Botany Curriculum for Non-Science Majors

Authors: Rosa M. Gambier, Jennifer L. Carlson

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In order to revitalize the science curriculum for botany courses for non-science majors, we have introduced the use of the medicinal plants into a first-year botany course. We have connected the use of scientific method, scientific inquiry and active learning in the classroom with the study of Western Traditional Medical Botany. The students have researched models of Botanical medicine and have designed a sustainable medicinal plants garden using native medicinal plants from the northeast. Through the semester, the students have researched their chosen species, planted seeds in the college greenhouse, collected germination ratios, growth ratios and have successfully produced a beginners medicinal plant garden. Phase II of the project will be to tie in SCCCs community outreach goals by involving the public in the expanded development of the garden as a way of sharing learning about medicinal plants and traditional medicine outside the classroom.

Keywords: medicinal plant garden, botany curriculum, active learning, community outreach

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18467 A Genetic Identification of Candida Species Causing Intravenous Catheter-Associated Candidemia in Heart Failure Patients

Authors: Seyed Reza Aghili, Tahereh Shokohi, Shirin Sadat Hashemi Fesharaki, Mohammad Ali Boroumand, Bahar Salmanian

Abstract:

Introduction: Intravenous catheter-associated fungal infection as nosocomial infection continue to be a deep problem among hospitalized patients, decreasing quality of life and adding healthcare costs. The capacity of catheters in the spread of candidemia in heart failure patients is obvious. The aim of this study was to evaluate the prevalence and genetic identification of Candida species in heart disorder patients. Material and Methods: This study was conducted in Tehran Hospital of Cardiology Center (Tehran, Iran, 2014) during 1.5 years on the patients hospitalized for at least 7 days and who had central or peripheral vein catheter. Culture of catheters, blood and skin of the location of catheter insertion were applied for detecting Candida colonies in 223 patients. Identification of Candida species was made on the basis of a combination of various phenotypic methods and confirmed by sequencing the ITS1-5.8S-ITS2 region amplified from the genomic DNA using PCR and the NCBI BLAST. Results: Of the 223 patients samples tested, we identified totally 15 Candida isolates obtained from 9 (4.04%) catheter cultures, 3 (1.35%) blood cultures and 2 (0.90%) skin cultures of the catheter insertion areas. On the base of ITS region sequencing, out of nine Candida isolates from catheter, 5(55.6%) C. albicans, 2(22.2%) C. glabrata, 1(11.1%) C. membranifiaciens and 1 (11.1%) C. tropicalis were identified. Among three Candida isolates from blood culture, C. tropicalis, C. carpophila and C. membranifiaciens were identified. Non-candida yeast isolated from one blood culture was Cryptococcus albidus. One case of C. glabrata and one case of Candida albicans were isolated from skin culture of the catheter insertion areas in patients with positive catheter culture. In these patients, ITS region of rDNA sequence showed a similarity between Candida isolated from the skin and catheter. However, the blood samples of these patients were negative for fungal growth. We report two cases of catheter-related candidemia caused by C. membranifiaciens and C. tropicalis on the base of genetic similarity of species isolated from blood and catheter which were treated successfully with intravenous fluconazole and catheter removal. In phenotypic identification methods, we could only identify C. albicans and C. tropicalis and other yeast isolates were diagnosed as Candida sp. Discussion: Although more than 200 species of Candida have been identified, only a few cause diseases in humans. There is some evidence that non-albicans infections are increasing. Many risk factors, including prior antibiotic therapy, use of a central venous catheter, surgery, and parenteral nutrition are considered to be associated with candidemia in hospitalized heart failure patients. Identifying the route of infection in candidemia is difficult. Non-albicans candida as the cause of candidemia is increasing dramatically. By using conventional method, many non-albicans isolates remain unidentified. So, using more sensitive and specific molecular genetic sequencing to clarify the aspects of epidemiology of the unknown candida species infections is essential. The positive blood and catheter cultures for candida isolates and high percentage of similarity of their ITS region of rDNA sequence in these two patients confirmed the diagnosis of intravenous catheter-associated candidemia.

Keywords: catheter-associated infections, heart failure patient, molecular genetic sequencing, ITS region of rDNA, Candidemia

Procedia PDF Downloads 333
18466 Cost Implications of Natural Resources Conflicts on Livelihoods of Farmers and Pastoralists in the North East Arid Zone of Nigeria

Authors: Ibrahim Ahmed Jajere

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Resource use conflicts capable of undermining of pastoralists’ livelihoods are on the increase in the North East Arid Zone of Nigeria. In order to expose socio - economic effects of conflicts and benefits of peace, this study assessed cost implications of farmers/pastoralists conflicts over natural resources. Interviews were conducted with 94 farmers, 90 agro-pastoralists and 91 pastoralists’ household heads. The farmers and agro-pastoralists were systematically sampled while pastoralists were located using snowballing. Both farmers and pastoralists suffered losses in the form of injuries to, and even death of household members, and loss of shelter. Farmers sustained losses of facilities and farm produce while pastoralists suffered loss and seizure of livestock, arrest of household members and forced migrations. The material losses in monetary terms amounted to 14,242,200.00 nairas for farmers, a figure higher than the 10,915,500.00 nairas incurred by pastoralists.

Keywords: cost, conflicts, farmers, pastoralists

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18465 Unsteady Simulation of Burning Off Carbon Deposition in a Coke Oven

Authors: Uzu-Kuei Hsu, Keh-Chin Chang, Joo-Guan Hang, Chang-Hsien Tai

Abstract:

Carbon Deposits are often occurred inside the industrial coke oven during the coking process. Accumulation of carbon deposits may cause a big issue, which seriously influences the coking operation. The carbon is burning off by injecting fresh air through pipes into coke oven which is an efficient way practically operated in industries. The burning off carbon deposition in coke oven performed by Computational Fluid Dynamics (CFD) method has provided an evaluation of the feasibility study. A three-dimensional, transient, turbulent reacting flow simulation has performed with three different injecting air flow rate and another kind of injecting configuration. The result shows that injection higher air flow rate would effectively reduce the carbon deposits. In the meantime, the opened charging holes would suck extra oxygen from the atmosphere to participate in reactions. In term of coke oven operating limits, the wall temperatures are monitored to prevent over-heating of the adiabatic walls during the burn-off process.

Keywords: coke oven, burning off, carbon deposits, carbon combustion, CFD

Procedia PDF Downloads 694
18464 A Systematic Review of the Transportability of Cognitive Therapy for the Treatment of PTSD among South African Survivors of Rape

Authors: Anita Padmanabhanunni

Abstract:

Trauma-focused cognitive-treatment (CT) models are among the most efficacious in treating PTSD arising from exposure to rape. However, these treatment approaches are severely under-utilised by South African mental health care practitioners owing to concerns around whether treatments developed in Western clinical contexts are transportable and applicable in routine clinical settings. One way of promoting the use of these efficacious treatments in local contexts is by identifying and appraising the evidence from local outcome studies. This paper presents the findings of a systematic review of research evidence from local outcome studies on the effectiveness of CT in the treatment of rape-related PTSD in South Africa. The study found that whilst limited research has been published in South Africa on the outcome of CT in the treatment of rape survivors, the studies that are available afford insights into the effectiveness of CT.

Keywords: cognitive treatment, PTSD, South Africa, transportability

Procedia PDF Downloads 340
18463 Machinability Study of A201-T7 Alloy

Authors: Onan Kilicaslan, Anil Kabaklarli, Levent Subasi, Erdem Bektas, Rifat Yilmaz

Abstract:

The Aluminum-Copper casting alloys are well known for their high mechanical strength, especially when compared to more commonly used Aluminum-Silicon alloys. A201 is one of the best in terms of strength vs. weight ratio among other aluminum alloys, which makes it suitable for premium quality casting applications in aerospace and automotive industries. It is reported that A201 has low castability, but it is easy to machine. However, there is a need to specifically determine the process window for feasible machining. This research investigates the machinability of A201 alloy after T7 heat treatment in terms of chip/burr formation, surface roughness, hardness, and microstructure. The samples are cast with low-pressure sand casting method and milling experiments are performed with uncoated carbide tools using different cutting speeds and feeds. Statistical analysis is used to correlate the machining parameters to surface integrity. It is found that there is a strong dependence of the cutting conditions on machinability and a process window is determined.

Keywords: A201-T7, machinability, milling, surface integrity

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18462 Leadership Dynamics and Teacher Engagement in Greek Education

Authors: Vasileios Floros

Abstract:

This article delves into the intricate interplay between leadership styles and teacher satisfaction within the Greek educational framework, underscoring the pivotal role of school leadership in shaping educational success and fostering a conducive school culture. Through a comprehensive analysis, the study explores various leadership theories, the psychological contract between teachers and leaders, and the impact of leadership on teacher job satisfaction and group dynamics within educational institutions. It highlights how leadership efficacy can significantly influence the organizational climate, teacher motivation, and, ultimately, educational outcomes. The findings suggest that effective leadership, characterized by a deep understanding of teacher psychology, thoughtful engagement with the school culture, and strategic application of leadership styles, can lead to heightened teacher satisfaction and enhanced educational performance. This research offers valuable insights for educational policymakers, school leaders, and the broader academic community interested in optimizing leadership practices to foster an enriching educational environment in Greece.

Keywords: educational leadership, teacher satisfaction, school culture, leadership styles, Greek education

Procedia PDF Downloads 53
18461 Low Term Aerobic Training Is Not Associated with Anti-Inflammatory in Obese Women

Authors: Zohreh Afsharmand, Sokhanguei Yahya

Abstract:

A growing body of literature suggests that that low-grade systemic inflammation associated to obesity plays a key role in the pathogenic mechanism of several disorders. In this study, the effect of 6 weeks aerobic training on IL-6 and IL-1B as inflammatory cytokine were investigated in adult obese women. For this purpose, 26 sedentary adult obese women were divided into exercise and control groups (n=12). Pre and post training of mentioned cytokines were measured in two groups. Student’s t-tests for paired samples were performed to determine whether there were significant within-group changes in the outcomes. A p value less than 0.05 was considered statistically significant. There were no statistically significant differences between the exercise and control groups with regard to anthropometrical markers or inflammatory cytokines. Despite the significant decrease in all anthropometrical markers, no significant differences were found in serum IL-6 and IL-1B by aerobic training with compared to baseline. Our findings indicate that aerobic training intervention for a short time is not associated with the anti-inflammatory property in obese women.

Keywords: aerobic training, cytokine, inflammation, obesity

Procedia PDF Downloads 351
18460 Topology Optimization of Structures with Web-Openings

Authors: D. K. Lee, S. M. Shin, J. H. Lee

Abstract:

Topology optimization technique utilizes constant element densities as design parameters. Finally, optimal distribution contours of the material densities between voids (0) and solids (1) in design domain represent the determination of topology. It means that regions with element density values become occupied by solids in design domain, while there are only void phases in regions where no density values exist. Therefore the void regions of topology optimization results provide design information to decide appropriate depositions of web-opening in structure. Contrary to the basic objective of the topology optimization technique which is to obtain optimal topology of structures, this present study proposes a new idea that topology optimization results can be also utilized for decision of proper web-opening’s position. Numerical examples of linear elastostatic structures demonstrate efficiency of methodological design processes using topology optimization in order to determinate the proper deposition of web-openings.

Keywords: topology optimization, web-opening, structure, element density, material

Procedia PDF Downloads 476