Search results for: half metallic ferrimagnetism
761 Atomic Layer Deposition of Metal Oxides on Si/C Materials for the Improved Cycling Stability of High-Capacity Lithium-Ion Batteries
Authors: Philipp Stehle, Dragoljub Vrankovic, Montaha Anjass
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Due to its high availability and extremely high specific capacity, silicon (Si) is the most promising anode material for next generation lithium-ion batteries (LIBs). However, Si anodes are suffering from high volume changes during cycling causing unstable solid-electrolyte interface (SEI). One approach for mitigation of these effects is to embed Si particles into a carbon matrix to create silicon/carbon composites (Si/C). These typically show more stable electrochemical performance than bare silicon materials. Nevertheless, the same failure mechanisms mentioned earlier appear in a less pronounced form. In this work, we further improved the cycling performance of two commercially available Si/C materials by coating thin metal oxide films of different thicknesses on the powders via Atomic Layer Deposition (ALD). The coated powders were analyzed via ICP-OES and AFM measurements. Si/C-graphite anodes with automotive-relevant loadings (~3.5 mAh/cm2) were processed out of the materials and tested in half coin cells (HCCs) and full pouch cells (FPCs). During long-term cycling in FPCs, a significant improvement was observed for some of the ALD-coated materials. After 500 cycles, the capacity retention was already up to 10% higher compared to the pristine materials. Cycling of the FPCs continued until they reached a state of health (SOH) of 80%. By this point, up to the triple number of cycles were achieved by ALD-coated compared to pristine anodes. Post-mortem analysis via various methods was carried out to evaluate the differences in SEI formation and thicknesses.Keywords: silicon anodes, li-ion batteries, atomic layer deposition, silicon-carbon composites, surface coatings
Procedia PDF Downloads 114760 A Self Beheld the Eyes of the Other: Reflections on Montesquieu's Persian Letters
Authors: Seyed Majid Alavi Shooshtari
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As a multi-layered prose piece of artistry and craftsmanship Charles de Secondat, baron de Montesquieu’s Persian Letters (1721) is a satirical work which records the experiences of two Persian noblemen, Usbek and Rica, traveling through France in the early eighteenth century. Montesquieu creates Persian Letters as a critique of the French society, a critical explanation of what was considered to be 'the Orient' in the period, and an invaluable historical document which illustrates the ways Europe and the East understood each other in the first half of the eighteenth century. However, Persian Letters is considered today, in part, an Orientalist text because of it presenting the culture of the East using stereotypical images. Although, when Montesquieu published Persian Letters, the term Orientalist was a harmless word for people who studied or took an interest in it, the ways in which this Western intellectual author exerts his critique of French social and political life through the eyes of Persian protagonists by placing the example of the Orient (the Other) at the service of an ongoing Eighteen century discourse does raise some Eastern eyebrows. The fact that Persian side of the novel is considered by some critics as a fanciful decor, and the letters sent home are seen as literary props, yet these Eastern men intelligently question the rationality of religious, state, military and cultural practices and uncover much of the absurdity, irrationality or frivolity of European life. By drawing on the insight that Montesquieu’s text problematizes the assumption that orientalism monolithically constructs the Orient as the Other, the present paper aims to examine how the innocent gaze of two Eastern travelers mirrors the ways Europe’s identity defines its-Self.Keywords: montesquieu, persian letters, ‘the orint’, identity politics, self, the other
Procedia PDF Downloads 106759 Laser Paint Stripping on Large Zones on AA 2024 Based Substrates
Authors: Selen Unaldi, Emmanuel Richaud, Matthieu Gervais, Laurent Berthe
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Aircrafts are painted with several layers to guarantee their protection from external attacks. For aluminum AA 2024-T3 (metallic structural part of the plane), a protective primer is applied to ensure its corrosion protection. On top of this layer, the top coat is applied for aesthetic aspects. During the lifetime of an aircraft, top coat stripping has an essential role which should be operated as an average of every four years. However, since conventional stripping processes create hazardous disposals and need long hours of labor work, alternative methods have been investigated. Amongst them, laser stripping appears as one of the most promising techniques not only because of the reasons mentioned above but also its controllable and monitorable aspects. The application of a laser beam from the coated side provides stripping, but the depth of the process should be well controlled in order to prevent damage to a substrate and the anticorrosion primer. Apart from that, thermal effects should be taken into account on the painted layers. As an alternative, we worked on developing a process that includes the usage of shock wave propagation to create the stripping via mechanical effects with the application of the beam from the substrate side (back face) of the samples. Laser stripping was applied on thickness-specified samples with a thickness deviation of 10-20%. First, the stripping threshold is determined as a function of power density which is the first flight off of the top coats. After obtaining threshold values, the same power densities were applied to specimens to create large stripping zones with a spot overlap of 10-40%. Layer characteristics were determined on specimens in terms of physicochemical properties and thickness range both before and after laser stripping in order to validate the substrate material health and coating properties. The substrate health is monitored by measuring the roughness of the laser-impacted zones and free surface energy tests (both before and after laser stripping). Also, Hugoniot Elastic Limit (HEL) is determined from VISAR diagnostic on AA 2024-T3 substrates (for the back face surface deformations). In addition, the coating properties are investigated as a function of adhesion levels and anticorrosion properties (neutral salt spray test). The influence of polyurethane top-coat thickness is studied in order to verify the laser stripping process window for industrial aircraft applications.Keywords: aircraft coatings, laser stripping, laser adhesion tests, epoxy, polyurethane
Procedia PDF Downloads 73758 Retail Strategy to Reduce Waste Keeping High Profit Utilizing Taylor's Law in Point-of-Sales Data
Authors: Gen Sakoda, Hideki Takayasu, Misako Takayasu
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Waste reduction is a fundamental problem for sustainability. Methods for waste reduction with point-of-sales (POS) data are proposed, utilizing the knowledge of a recent econophysics study on a statistical property of POS data. Concretely, the non-stationary time series analysis method based on the Particle Filter is developed, which considers abnormal fluctuation scaling known as Taylor's law. This method is extended for handling incomplete sales data because of stock-outs by introducing maximum likelihood estimation for censored data. The way for optimal stock determination with pricing the cost of waste reduction is also proposed. This study focuses on the examination of the methods for large sales numbers where Taylor's law is obvious. Numerical analysis using aggregated POS data shows the effectiveness of the methods to reduce food waste maintaining a high profit for large sales numbers. Moreover, the way of pricing the cost of waste reduction reveals that a small profit loss realizes substantial waste reduction, especially in the case that the proportionality constant of Taylor’s law is small. Specifically, around 1% profit loss realizes half disposal at =0.12, which is the actual value of processed food items used in this research. The methods provide practical and effective solutions for waste reduction keeping a high profit, especially with large sales numbers.Keywords: food waste reduction, particle filter, point-of-sales, sustainable development goals, Taylor's law, time series analysis
Procedia PDF Downloads 128757 The Impact of Women’s Leadership in Panchayati Raj Institutions: Some of the Insights on Indian Rural Governance
Authors: Avneet Kaur
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India is a nation of villages. Traditionally, women had enjoyed a high social status in India. Our mythology, folklore and history are full of women who were epitomes of virtue, wisdom, power, and position. The important concern about their entry into the politics is of great importance all over the world. Women have performed excellently in social, economic and political sphere. However, the fact remains that despite constituting half of the population their representation among elected post continue to remain negligible in Panchayati Raj Institutions. Women in India suffered from many social economic handicaps such as illiteracy, economically dependent, social customs, traditions and rituals that are the main causes of their inactive participation in local governance. There is still widespread patriarchal outlook in the villages and the lack of experience on the part of women leadership are some of the major issues of debate. The implementation of the 73rd Amendment Act of the Indian Constitution in 1992 reserved 1/3 rd of the seats for women empowerment. It was a major step to encourage them to take part in the village politics. This kind of revolution was the beginning of women leadership in villages. The paper intends to study the role and importance of women leadership in Panchayati Raj Institutions in India. The paper is divided into four sections. First section deals with the introduction by taking into account the available research on this particular subject. Second section talks about the role played by women leadership in these institutions after the passing of 73rd Amendment Act. Third section deals with some of the critical insights of the study by discussing the problems faced by the active women’s leadership at the grassroots. Finally, the paper concludes with policy suggestions.Keywords: women, leadership, grassroots, Panchayati Raj
Procedia PDF Downloads 271756 Feasibility Study of Women’s Participation in the Renovation of the Worn-Out Texture: A Case Study Investigation of the Worn-Out Urban Texture of the Tehran Helal-Ahmar Region
Authors: Bahram Siavashpor, Zeynab Haji Abdolhadi
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The issue of the worn out textures is one of the urban community challenges in which, undoubtedly, the intervention is impossible without the social involvement. Some believe that in the worn out areas the most important intervention challenge is the social issues, and the most important social issue, in the intervention in the worn out areas, is how to attract public participation. Participation by itself has a widespread literature and despite relative acceptance, it should be said that planners, managers and designers are not always successful in attracting public participation. If participation means the intervention of all the residents in the neighborhood, women’s community forms half of these residents, but they are neglected in the participatory planning. It is important to know that to what extent the presence of women’s community in the related participation to the worn out textures affects the success of the projects. The present study hypotheses emphasize the effectiveness of women than men in involvement of the renovation and reforming projects. A case study was selected to investigate this hypothesis in order to test it through doing a questionnaire and visiting the place. Tehran Helal Ahmar region located in district 11 has 2740 households in which 51% are men and 49% women. The statistical population consists of 150 men and women of this area selected randomly. In the present study, interview technique with the executives was used as well as questionnaire along collecting the related research. The hypothesis analysis was carried out through SPSS and Excel software, in which two tests ‘Man-Whitney’ and ‘chi-square’ were used. The results indicate that women are empowered in the participation and renovation of the area, but it is necessary to rectify men’s attitude towards women’s ability in terms of women participation.Keywords: renovation, social involvement, women’s participation, worn out texture
Procedia PDF Downloads 193755 Design of Two-Channel Quadrature Mirror Filter Banks Using a Transformation Approach
Authors: Ju-Hong Lee, Yi-Lin Shieh
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Two-dimensional (2-D) quadrature mirror filter (QMF) banks have been widely considered for high-quality coding of image and video data at low bit rates. Without implementing subband coding, a 2-D QMF bank is required to have an exactly linear-phase response without magnitude distortion, i.e., the perfect reconstruction (PR) characteristics. The design problem of 2-D QMF banks with the PR characteristics has been considered in the literature for many years. This paper presents a transformation approach for designing 2-D two-channel QMF banks. Under a suitable one-dimensional (1-D) to two-dimensional (2-D) transformation with a specified decimation/interpolation matrix, the analysis and synthesis filters of the QMF bank are composed of 1-D causal and stable digital allpass filters (DAFs) and possess the 2-D doubly complementary half-band (DC-HB) property. This facilitates the design problem of the two-channel QMF banks by finding the real coefficients of the 1-D recursive DAFs. The design problem is formulated based on the minimax phase approximation for the 1-D DAFs. A novel objective function is then derived to obtain an optimization for 1-D minimax phase approximation. As a result, the problem of minimizing the objective function can be simply solved by using the well-known weighted least-squares (WLS) algorithm in the minimax (L∞) optimal sense. The novelty of the proposed design method is that the design procedure is very simple and the designed 2-D QMF bank achieves perfect magnitude response and possesses satisfactory phase response. Simulation results show that the proposed design method provides much better design performance and much less design complexity as compared with the existing techniques.Keywords: Quincunx QMF bank, doubly complementary filter, digital allpass filter, WLS algorithm
Procedia PDF Downloads 221754 Estimation Model for Concrete Slump Recovery by Using Superplasticizer
Authors: Chaiyakrit Raoupatham, Ram Hari Dhakal, Chalermchai Wanichlamlert
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This paper is aimed to introduce the solution of concrete slump recovery using chemical admixture type-F (superplasticizer, naphthalene base) to the practice, in order to solve unusable concrete problem due to concrete loss its slump, especially for those tropical countries that have faster slump loss rate. In the other hand, randomly adding superplasticizer into concrete can cause concrete to segregate. Therefore, this paper also develops the estimation model used to calculate amount of second dose of superplasticizer need for concrete slump recovery. Fresh properties of ordinary Portland cement concrete with volumetric ratio of paste to void between aggregate (paste content) of 1.1-1.3 with water-cement ratio zone of 0.30 to 0.67 and initial superplasticizer (naphthalene base) of 0.25%- 1.6% were tested for initial slump and slump loss for every 30 minutes for one and half hour by slump cone test. Those concretes with slump loss range from 10% to 90% were re-dosed and successfully recovered back to its initial slump. Slump after re-dosed was tested by slump cone test. From the result, it has been concluded that, slump loss was slower for those mix with high initial dose of superplasticizer due to addition of superplasticizer will disturb cement hydration. The required second dose of superplasticizer was affected by two major parameter, which were water-cement ratio and paste content, where lower water-cement ratio and paste content cause an increase in require second dose of superplasticizer. The amount of second dose of superplasticizer is higher as the solid content within the system is increase, solid can be either from cement particles or aggregate. The data was analyzed to form an equation use to estimate the amount of second dosage requirement of superplasticizer to recovery slump to its original.Keywords: estimation model, second superplasticizer dosage, slump loss, slump recovery
Procedia PDF Downloads 195753 Feeding Practices and Malnutrition among under Five Children in Communities of Kuje Area Council, Federal Capital Territory Abuja, Nigeria
Authors: Clementina Ebere Okoro, Olumuyiwa Adeyemi Owolabi, Doris Bola James, Aloysius Nwabugo Maduforo, Andrew Lingililani Mbewe, Christopher Osaruwanmwen Isokpunwu
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Poor dietary practices and malnutrition, including severe acute malnutrition among under-five children in Nigeria has remained a great public health concern. This study assessed infant and young child feeding practices and nutritional status of under-five children to determine the prevalence of malnutrition of under-five children in Kuje area council, Abuja. The study was a cross-sectional study. Multi-stage sampling techniques was used in selecting the population that was studied. Probability proportion by size was applied in choosing 30 clusters for the survey using ENA for SMART software 2011 version. Questionnaires were used to obtain information from the population, while appropriate equipment was used for measurements of anthropometric parameters. The data was also subjected to statistical analysis. Results were presented in tables and figures. The result showed that 96.7% of the children were breastfed, 30.6% had early initiation to breastfeeding within first hour of birth and 22.4% were breastfed exclusively up to 6 months, 69.8% fed infants’ colostrum, while 30.2% discarded colostrum. About half of the respondents (49.1%) introduced complementary feeding before six months and 23.2% introduced it after six months while 27.7% had age appropriate timely introduction of complementary feeding. The anthropometric result showed that the prevalence of global acute malnutrition (GAM) was 12.8%, severe wasting prevalence was 5.4%, moderate wasting was 7.4%, underweight was 24.4%, stunting was 40.3% and overweight was 7.0%. The result showed that there is a high prevalence of malnutrition among under-five children in KujeKeywords: malnutrition, under five children, breastfeeding, complementary feeding
Procedia PDF Downloads 259752 Teenagers in Conflict with Law: Exploratory Study about Psychic Suffering
Authors: Carolina Alcântara, Ileno Costa
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This study had the objective to systemize the main psycho-social and socioeducational aspects that related with the psychic suffering of adolescents in conflict of law and freedom privation. This research wanted to verify the signals and symptoms identified trough themselves perceptions related to their condition of health/insanity. In a similar way, it was objectified to know the opinions of the ambient conditions of the institution the use of the currently available resources for Health Service and Educational Service. The methodological proposal is based on the quant-qualitative analysis of interviews half-structuralized carried through with 36 teenagers was using psychiatric medication continuously. The data had pointed the experiences of sleeplessness and nightmares, associates or not with experiences of loss of reality (hallucinations) had constituted the illness most frequent. The self-punishment behavior appeared at second place. With regard to the ambient factors, it was verified that institution had, in general way, guaranteed the physical integrity and the maintenance of the health. Amongst the current available resources of Health Service, the administration of anticonvulsivants, in association with other psychotropic drugs has been widely used. The school was viewed as important device of available in the institution. By means of the adolescent’s understanding who do not like to go to the school, they don’t disqualify the knowledge, in contrast, they wanted for knowledge, however, they were frustrated for not having their educational supplies adequately, affirming that the school is weak or they do not learn. Finally, among the possible conclusions guided for the Winnicott’s thought, it was observed that institution in analysis is a representative of the paternal function. However, to begin the self-cure process is necessary that formation of therapeutical bonds. The group of teachers is identified as the main tool of change.Keywords: serious psychic suffering, adolescent in conflict with the law, delinquency, privation of freedom
Procedia PDF Downloads 233751 Assessment of Nurse's Knowledge Toward Infection Control for Wound Care in Governmental Hospital at Amran City-Yemen
Authors: Fares Mahdi
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Background: Infection control is an important concern for all health care professionals, especially nurses. Nurses have a higher risk for both self-acquiring and transmitting infections to other patients. Aim of this study: to assess nurses' knowledge regarding infection control for wound care. Methodology: a descriptive research design was used in the study. The total number studied sample was 200 nurses, were conducting in Amran Public Hospitals in Amran City- Yemen. The study covered sample nurses in the hospital according to the study population; a standard closed-ended questionnaire was used to collect the data. Results: The results showed less than half (37.5 %) of nurses were from 22 May Hospital, also followed by (62.5%) of them were from Maternal and Child Hospital. Also according to the department name. Most (22.5%) of nurses worked in an intensive care unit, followed by (20%) of them were working in the pediatric world, also about (19%) of them were working in the surgical department. While in finally, only about (8.5%) of them worked from another department. According to course training, The results showed about (21%) of nurses had course training in wound care management. At the same time, others (79%) of them have not had course training in wound care management. According to the total nurse's knowledge of infection control for wound care, that find more than two-thirds (68%) of nurses had fair knowledge according to total all of nurse's knowledge of infection control wound care. Conclusion:The results showed that more than two-thirds (68%) of nurses had fair knowledge according to total all of the nurse's knowledge of infection control for wound care. Recommendations: There should be providing training program about infection control masseurs and it's important for new employees of nurses. Providing continuing refreshment training courses about infection control programs and about evidence-based practice in infection control for all health care teams.Keywords: assessment, knowledge, infection control, wound care, nurses, amran hospitals
Procedia PDF Downloads 79750 Geostatistical Simulation of Carcinogenic Industrial Effluent on the Irrigated Soil and Groundwater, District Sheikhupura, Pakistan
Authors: Asma Shaheen, Javed Iqbal
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The water resources are depleting due to an intrusion of industrial pollution. There are clusters of industries including leather tanning, textiles, batteries, and chemical causing contamination. These industries use bulk quantity of water and discharge it with toxic effluents. The penetration of heavy metals through irrigation from industrial effluent has toxic effect on soil and groundwater. There was strong positive significant correlation between all the heavy metals in three media of industrial effluent, soil and groundwater (P < 0.001). The metal to the metal association was supported by dendrograms using cluster analysis. The geospatial variability was assessed by using geographically weighted regression (GWR) and pollution model to identify the simulation of carcinogenic elements in soil and groundwater. The principal component analysis identified the metals source, 48.8% variation in factor 1 have significant loading for sodium (Na), calcium (Ca), magnesium (Mg), iron (Fe), chromium (Cr), nickel (Ni), lead (Pb) and zinc (Zn) of tannery effluent-based process. In soil and groundwater, the metals have significant loading in factor 1 representing more than half of the total variation with 51.3 % and 53.6 % respectively which showed that pollutants in soil and water were driven by industrial effluent. The cumulative eigen values for the three media were also found to be greater than 1 representing significant clustering of related heavy metals. The results showed that heavy metals from industrial processes are seeping up toxic trace metals in the soil and groundwater. The poisonous pollutants from heavy metals turned the fresh resources of groundwater into unusable water. The availability of fresh water for irrigation and domestic use is being alarming.Keywords: groundwater, geostatistical, heavy metals, industrial effluent
Procedia PDF Downloads 225749 The Three-Zone Composite Productivity Model of Multi-Fractured Horizontal Wells under Different Diffusion Coefficients in a Shale Gas Reservoir
Authors: Weiyao Zhu, Qian Qi, Ming Yue, Dongxu Ma
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Due to the nano-micro pore structures and the massive multi-stage multi-cluster hydraulic fracturing in shale gas reservoirs, the multi-scale seepage flows are much more complicated than in most other conventional reservoirs, and are crucial for the economic development of shale gas. In this study, a new multi-scale non-linear flow model was established and simplified, based on different diffusion and slip correction coefficients. Due to the fact that different flow laws existed between the fracture network and matrix zone, a three-zone composite model was proposed. Then, according to the conformal transformation combined with the law of equivalent percolation resistance, the productivity equation of a horizontal fractured well, with consideration given to diffusion, slip, desorption, and absorption, was built. Also, an analytic solution was derived, and the interference of the multi-cluster fractures was analyzed. The results indicated that the diffusion of the shale gas was mainly in the transition and Fick diffusion regions. The matrix permeability was found to be influenced by slippage and diffusion, which was determined by the pore pressure and diameter according to the Knudsen number. It was determined that, with the increased half-lengths of the fracture clusters, flow conductivity of the fractures, and permeability of the fracture network, the productivity of the fractured well also increased. Meanwhile, with the increased number of fractures, the distance between the fractures decreased, and the productivity slowly increased due to the mutual interference of the fractures. In regard to the fractured horizontal wells, the free gas was found to majorly contribute to the productivity, while the contribution of the desorption increased with the increased pressure differences.Keywords: multi-scale, fracture network, composite model, productivity
Procedia PDF Downloads 263748 Knowledge and Attitude towards Helicobacter pylori: Awareness about Health Impacts of H. pylori Gastric Ulcer and Its Carcinogenic Potential among Adults in Sharjah
Authors: Abdullah Malek, Muzn Al Khaldi, Lian Odeh, Atheer Tariq, Mohammad Al Fardan, Hiba Barqawi
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H. pylori bacterium is a known underlying agent for gastritis, peptic ulcer disease, and gastric cancer and is believed to infect half of the world’s population. Even with the ubiquity of H. pylori bacterium, there is lack of knowledge regarding its modes of transmission, associated diseases, carcinogenic effect and means of prevention; especially in the UAE. A cross sectional study of 500 participants, of which 58% (n= 289) of the respondents were female, and 42% (n=210) were male, was conducted in Sharjah to assess the knowledge, and explore the attitudes and practices among UAE residents towards Helicobacter Pylori and its associated PUD as well as its carcinogenic nature. A structured self-administered questionnaire was distributed to the target population to establish their demographic background and selected aspects of their lifestyle. General knowledge about H. Pylori was poor, only 24.6% stated they have heard of H. pylori. Attitudes towards prevention and practices were relatively poor as well. Subjects who suffered from severe symptoms (ALARM symptoms) had significantly lower habit scores than those with mild and moderate symptoms (p=0.0078**). To the authours’ knowledge, no previous studies were conducted in the United Arab Emirates regarding the epidemiology of the infection to detect the extent of H. Pylori’s impact on the public health. The results of this study can be used to draw conclusions about the average knowledge of the UAE population regarding H. pylori. It can also be a starting point to devise new education programs and campaigns that raise awareness of this health issue which could be easily avoided with early diagnosis and antibiotic treatment.Keywords: chronic gastritis, community health, gastric cancer, Helicobacter pylori, peptic ulcers
Procedia PDF Downloads 250747 Fuzzy Logic for Control and Automatic Operation of Natural Ventilation in Buildings
Authors: Ekpeti Bukola Grace, Mahmoudi Sabar Esmail, Chaer Issa
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Global energy consumption has been increasing steadily over the last half - century, and this trend is projected to continue. As energy demand rises in many countries throughout the world due to population growth, natural ventilation in buildings has been identified as a viable option for lowering these demands, saving costs, and also lowering CO2 emissions. However, natural ventilation is driven by forces that are generally unpredictable in nature thus, it is important to manage the resulting airflow in order to maintain pleasant indoor conditions, making it a complex system that necessitates specific control approaches. The effective application of fuzzy logic technique amidst other intelligent systems is one of the best ways to bridge this gap, as its control dynamics relates more to human reasoning and linguistic descriptions. This article reviewed existing literature and presented practical solutions by applying fuzzy logic control with optimized techniques, selected input parameters, and expert rules to design a more effective control system. The control monitors used indoor temperature, outdoor temperature, carbon-dioxide levels, wind velocity, and rain as input variables to the system, while the output variable remains the control of window opening. This is achieved through the use of fuzzy logic control tool box in MATLAB and running simulations on SIMULINK to validate the effectiveness of the proposed system. Comparison analysis model via simulation is carried out, and with the data obtained, an improvement in control actions and energy savings was recorded.Keywords: fuzzy logic, intelligent control systems, natural ventilation, optimization
Procedia PDF Downloads 122746 Review of Capitalization of Construction Industry on Sustainable Risk Management in Nigeria
Authors: Nnadi Ezekiel Ejiofor
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The construction industry plays a decisive role in the healthy development of any nation. Not only large but even small construction projects contribute to a country’s economic growth. There is a need for good management to ensure successful delivery and sustainability because of the plethora of risks that have resulted in low-profit margins for contractors, cost and schedule overruns, poor quality delivery, and abandoned projects. This research reviewed Capitalization on Sustainable Risk Management. Questionnaires and oral interviews conducted were utilized as means of data collection. One hundred and ninety-eight (198) large construction firms in Nigeria form the population of this study. 15 (fifteen) companies that emanated from merger and acquisition were used for the study. The instruments used for data collection were a researcher-developed structured questionnaire based on a five-point rating scale, interviews, focus group discussion, and secondary sources (bill of quantities and stock and exchange commission). The instrument was validated by two experts in the field. The reliability of the instrument was established by applying the split-half method. Kendall’s coefficient of concordance was used to test the data, and a degree of agreement was obtained. Data were subjected to descriptive statistics and analyzed using analysis of variance, t-test, and SPSS. The identified impacts of capitalization were an increase in turnover (24.5%), improvement in the image (24.5%), risk reduction (20%), business expansion (17.3%), and geographical spread (13.6%). The study strongly advocates the inclusion of risk management evaluation as part of the construction procurement process.Keywords: capitalization, project delivery, risks, risk management, sustainability
Procedia PDF Downloads 50745 An Efficient Automated Radiation Measuring System for Plasma Monopole Antenna
Authors: Gurkirandeep Kaur, Rana Pratap Yadav
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This experimental study is aimed to examine the radiation characteristics of different plasma structures of a surface wave-driven plasma antenna by an automated measuring system. In this study, a 30 cm long plasma column of argon gas with a diameter of 3 cm is excited by surface wave discharge mechanism operating at 13.56 MHz with RF power level up to 100 Watts and gas pressure between 0.01 to 0.05 mb. The study reveals that a single structured plasma monopole can be modified into an array of plasma antenna elements by forming multiple striations or plasma blobs inside the discharge tube by altering the values of plasma properties such as working pressure, operating frequency, input RF power, discharge tube dimensions, i.e., length, radius, and thickness. It is also reported that plasma length, electron density, and conductivity are functions of operating plasma parameters and controlled by changing working pressure and input power. To investigate the antenna radiation efficiency for the far-field region, an automation-based radiation measuring system has been fabricated and presented in detail. This developed automated system involves a combined setup of controller, dc servo motors, vector network analyzer, and computing device to evaluate the radiation intensity, directivity, gain and efficiency of plasma antenna. In this system, the controller is connected to multiple motors for moving aluminum shafts in both elevation and azimuthal plane whereas radiation from plasma monopole antenna is measured by a Vector Network Analyser (VNA) which is further wired up with the computing device to display radiations in polar plot forms. Here, the radiation characteristics of both continuous and array plasma monopole antenna have been studied for various working plasma parameters. The experimental results clearly indicate that the plasma antenna is as efficient as a metallic antenna. The radiation from plasma monopole antenna is significantly influenced by plasma properties which provides a wider range in radiation pattern where desired radiation parameters like beam-width, the direction of radiation, radiation intensity, antenna efficiency, etc. can be achieved in a single monopole. Due to its wide range of selectivity in radiation pattern; this can meet the demands of wider bandwidth to get high data speed in communication systems. Moreover, this developed system provides an efficient and cost-effective solution for measuring the radiation pattern in far-field zone for any kind of antenna system.Keywords: antenna radiation characteristics, dynamically reconfigurable, plasma antenna, plasma column, plasma striations, surface wave
Procedia PDF Downloads 112744 Nutritional Status of People Living with Human Immuno Virus/Acquired Immune Deficiency Syndrome Attending Anti-Retro Viral Treatment Clinic of BP Koirala Institute of Health Sciences, Nepal
Authors: Ghimire K., Mehta R. S., Parajuli P., Chettri R.
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Background: Malnutrition is a common hallmark of Human Immuno Virus (HIV) disease. It plays a synergistic role in immunosuppression which is initiated by Human Immuno Virus itself, and malnutrition forms an independent risk factor for disease progression. Objectives: The objective of the study is to assess the nutritional status of the people living with Human Immuno Virus/Acquired Immune Deficiency Syndrome attending the Anti-Retro viral Treatment Clinic and find the association of nutritional status with different socio-demographic variables. Methods: A total of 101 people living with HIV/AIDS (PLWHA) were selected by convenient sampling technique. The study was conducted at the ART clinic of BPKIHS. A subjective global assessment tool was used for data collection. Descriptive and inferential statistics were used for data analysis. Results: The study demonstrated that the mean age of the respondents was 40.97+8.650 years. 65.3% were well-nourished, and 34.7% of the participants were mildly/moderately malnourished, whereas none of them were severely malnourished. BMI was statistically significant with education status, family income, and duration of illness of the participants, and nutritional status was statistically significant with gender, marital status, education status, and family history of HIV. Conclusion: On the basis of the result, it can be concluded that more than half of the respondents were well nourished. Gender, marital status, and education are associated with nutritional status.Keywords: nutritional status, people living with HIV/AIDS, ART treatment, Nepal
Procedia PDF Downloads 82743 Quantification and Identification of the Main Components of the Biomass of the Microalgae Scenedesmus SP. – Prospection of Molecules of Commercial Interest
Authors: Carolina V. Viegas, Monique Gonçalves, Gisel Chenard Diaz, Yordanka Reyes Cruz, Donato Alexandre Gomes Aranda
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To develop the massive cultivation of microalgae, it is necessary to isolate and characterize the species, improving genetic tools in search of specific characteristics. Therefore, the detection, identification and quantification of the compounds that compose the Scenedesmus sp. were prerequisites to verify the potential of these microalgae. The main objective of this work was to carry out the characterization of Scenedesmus sp. as to the content of ash, carbohydrates, proteins and lipids as well as the determination of the composition of their lipid classes and main fatty acids. The biomass of Scenedesmus sp, showed 15,29 ± 0,23 % of ash and CaO (36,17 %) was the main component of this fraction, The total protein and carbohydrate content of the biomass was 40,74 ± 1,01 % and 23,37 ± 0,95 %, respectively, proving to be a potential source of proteins as well as carbohydrates for the production of ethanol via fermentation, The lipid contents extracted via Bligh & Dyer and in situ saponification were 8,18 ± 0,13 % and 4,11 ± 0,11 %, respectively. In the lipid extracts obtained via Bligh & Dyer, approximately 50 % of the composition of this fraction consists of fatty compounds, while the other half is composed of an unsaponifiable fraction composed mainly of chlorophylls, phytosterols and carotenes. From the lowest yield, it was possible to obtain a selectivity of 92,14 % for fatty components (fatty acids and fatty esters) confirmed through the infrared spectroscopy technique. The presence of polyunsaturated acids (~45 %) in the lipid extracts indicated the potential of this fraction as a source of nutraceuticals. The results indicate that the biomass of Scenedesmus sp, can become a promising potential source for obtaining polyunsaturated fatty acids, carotenoids and proteins as well as the simultaneous obtainment of different compounds of high commercial value.Keywords: microalgae, Desmodesmus, lipid classes, fatty acid profile, proteins, carbohydrates
Procedia PDF Downloads 86742 Selection Criteria in the Spanish Secondary Education Content and Language Integrated Learning (CLIL) Programmes and Their Effect on Code-Switching in CLIL Methodology
Authors: Dembele Dembele, Philippe
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Several Second Language Acquisition (SLA) studies have stressed the benefits of Content and Language Integrated Learning (CLIL) and shown how CLIL students outperformed their non-CLIL counterparts in many L2 skills. However, numerous experimental CLIL programs seem to have mainly targeted above-average and rather highly motivated language learners. The need to understand the impact of the student’s language proficiency on code-switching in CLIL instruction motivated this study. Therefore, determining the implications of the students’ low-language proficiency for CLIL methodology, as well as the frequency with which CLIL teachers use the main pedagogical functions of code-switching, seemed crucial for a Spanish CLIL instruction on a large scale. In the mixed-method approach adopted, ten face-to-face interviews were conducted in nine Valencian public secondary education schools, while over 30 CLIL teachers also contributed with their experience in two online survey questionnaires. The results showed the crucial role language proficiency plays in the Valencian CLIL/Plurilingual selection criteria. The presence of a substantial number of low-language proficient students in CLIL groups, which in turn implied important methodological consequences, was another finding of the study. Indeed, though the pedagogical use of L1 was confirmed as an extended practice among CLIL teachers, more than half of the participants perceived that code-switching impaired attaining their CLIL lesson objectives. Therein, the dissertation highlights the need for more extensive empirical research on how code-switching could prove beneficial in CLIL instruction involving low-language proficient students while maintaining the maximum possible exposure to the target language.Keywords: CLIL methodology, low language proficiency, code switching, selection criteria, code-switching functions
Procedia PDF Downloads 72741 Reproductive Health Knowledge, Attitude and Health Services Utilization among Adolescents in Kaski District of Nepal
Authors: Dipendra Kumar Yadav, Rajani Ghimire, Saroj Yadav
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Background: The concern about adolescent on reproductive health has grown due to unprecedented increasing rates of early pregnancies and sexually transmitted Infections and they do not have adequate awareness and knowledge about it. Access to these services as well as information about them is, therefore, crucial for adolescents to utilize and benefit from sexual and reproductive health services. The objective of the study was to assess the reproductive health knowledge, attitude and health services utilization among adolescents in rural and urban areas of Kaski district. Materials and Methods: A community-based descriptive cross-sectional study was conducted among adolescents (10-19 years of age) in rural and urban areas of Kaski district, Nepal. The period of data collection was October to November, 2014. Altogether 419 participants were taken for the study. Results: The mean age of the respondents was 15.86 and standard deviation was ±2.305. More than half (58.7 %) of the respondents were females and 41.3 % were males. Out of 419, majority (78.8%) of the respondents were known about family planning, among them only 70 % of respondents were aware about family planning methods. Fifty-one percentages of the respondents were aware about the sexually transmitted diseases. Before giving a birth there is need to consult with partner with this fact 68.7 % of the respondents were agree, 23.6 % of them were neutral and very few (7.6%) of them were disagree. Nearly twenty six percentage of the respondents were faced the reproductive health problems within one month. Out of 107 respondents, 57.9 % did not utilize reproductive health services because of different reasons. Conclusions: The overall level of knowledge towards reproductive health among adolescents was found low. However, levels of attitude towards different reproductive health components were found favorable. Only 42.1% of the respondents were utilized reproductive health services among those who was faced the reproductive health problems within one month which was low coverage of reproductive health services utilization.Keywords: reproductive health knowledge, reproductive health attitudes, adolescent, service utilization
Procedia PDF Downloads 397740 Neuroprotective Effects of Dehydroepiandrosterone (DHEA) in Rat Model of Alzheimer’s Disease
Authors: Hanan F. Aly, Fateheya M. Metwally, Hanaa H. Ahmed
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The current study is undertaken to elucidate a possible neuroprotective role of dehydroepiandrosterone (DHEA) against the development of Alzheimer’s disease in experimental rat model. Alzheimer’s disease was produced in young female ovariectomized rats by intraperitoneal administration of AlCl3 (4.2 mg/kg body weight) daily for 12 weeks. Half of these animals also received orally DHEA (250 mg/kg body weight, three times weekly) for 18 weeks. Control groups of animals received either DHAE alone, or no DHEA, or were not ovariectomized. After such treatment the animals were analyzed for oxidative stress biomarkers such as hydrogen peroxide, nitric oxide and malondialdehyde, total antioxidant capacity, reduced glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase and catalase activities, antiapoptotic marker Bcl-2 and brain derived neurotrophic factor. Also, brain cholinergic markers (acetylcholinesterase and acetylcholine) were determined. The results revealed significant increase in oxidative stress parameters associated with significant decrease in the antioxidant enzyme activities in Al-intoxicated ovariectomized rats. Significant depletion in brain Bcl-2 and brain-derived neurotrophic factor levels were also detected. Moreover, significant elevations in brain acetylcholinesterase activity accompanied with significant reduction in acetylcholine level were recorded. Significant amelioration in all investigated parameters was detected as a result of treatment of Al-intoxicated ovariectomized rats with DHEA. These results were confirmed by histological examination of brain sections. These results clearly indicate a neuroprotective effect of DHEA against Alzheimer’s disease.Keywords: Alzheimer’s disease, oxidative stress, apoptosis, dehydroepiandrosterone
Procedia PDF Downloads 317739 Predictors of Ante-Natal Care and Health Facility Delivery Services Utilization in a Rural Area in Plateau State
Authors: Lilian A. Okeke, I. Okeke, N. Waziri, S. Balogun, P. Nguku, O. Fawole
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Background: Access to ante-natal care services promotes safe motherhood and delivery with improved maternal and neonatal outcome. We conducted this study to identify factors influencing the utilization of antenatal care (ANC) and health delivery services. Methods: We conducted a cross sectional study. Households were numbered and a one in three sample was selected using a systematic sampling method. One hundred and ninety eight women who were either pregnant or had previous deliveries were interviewed using pretested structured questionnaires to obtain information on their socio-demographic characteristics, and reasons for non-utilization of ANC and health delivery services. We performed univariate and bivariate analysis using Epi info version 3.5.3. Results: The age of respondents ranged from (17-55 years) with a median age of 29 years. One hundred and ninety two (97%) utilized antenatal care services. Ninety three (47.9%) attended ANC at second trimester. More than half (58.6%) had ≥ 4 visits to ANC. One hundred and thirty one (66.2%) had their last delivery at home by a traditional birth attendant. Factors associated with ANC and health facility delivery services utilization were: age group 45-55 (OR 0.01; 95% CI: 0.00-0.16) and > 55 years (OR 0.03; 95% CI: 0.00-0.60), wife’s educational status (OR 3.17; 95% CI: 1.66-8.30), husband’s permission (OR 11.8; 95% CI 2.19-63.62), and distance ≥ 5km (OR 0.33; 95% CI: 0.16-0.60). Conclusion: ANC services were well utilized. Most women did not book early and had their last delivery at home. Predictors of ANC use and health facility delivery were age, wife’s educational status, husband's permission and long distance from health facility. A one-day health sensitization of the benefits of ANC utilization and the dangers of delivering at home was implemented.Keywords: ante natal care, health facility, delivery services, rural area, Plateau state
Procedia PDF Downloads 366738 Optimal Approach for Siewert Type Ⅱ Adenocarcinoma of the Esophagogastric Junction: A Systematic Review and Metanalysis
Authors: Maatouk Mohamed, Nouira Mariem
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Background and aims: Healthcare-associated infections (HAI) represent a major public health problem worldwide. They represent one of the most serious adverse events in health care. The objectives of our study were to estimate the prevalence of HAI at the Charles Nicolle Hospital (CNH) and to identify the main associated factors as well as to estimate the frequency of antibiotic use. Methods: It was a cross sectional study at the CNH with a unique passage per department (OctoberDecember 2018). All patients present at the wards for more than 48 hours were included. All patients from outpatient consultations, emergency and dialysis departments were not included. The site definitions of infections proposed by the Centers for Disease Control and Prevention (CDC) were used. Only clinically and/or microbiologically confirmed active HAIs were included. Results: A total of 318 patients were included with a mean age of 52 years and a sex ratio (Female/Male) of 1.05. A total of 41 patients had one or more active HAIs, corresponding to a prevalence of 13.1% (95% CI: 9.3%-16.9%). The most frequent sites infections were urinary tract infections and pneumonia. Multivariate analysis among adult patients (>=18 years) (n=261), revealed that infection on admission (p=0.01), alcoholism (p=0.01), high blood pressure (p=0.008), having at least one invasive device inserted (p=0.004), and history of recent surgery (p=0.03), increased significantly the risk of HAIs. More than 1 of 3 patients (35.4%) were under antibiotics on the day of the survey, of which more than half (57.4%) were under 2 or more types of antibiotics. Conclusion: The prevalence of HAIs and antibiotic prescriptions at the CNH were considerably high. An infection prevention and control committee, as well as the development of an Antibiotic stewardship program with continuous monitoring using repeated prevalence surveys must be implemented to limit the frequency of these infections effectively.Keywords: tumors, oesophagectomy, esophagogastric junction, systematic review
Procedia PDF Downloads 76737 Physicochemical Properties and Thermal Inactivation of Polyphenol Oxidase of African Bush Mango (Irvingia Gabonensis) Fruit
Authors: Catherine Joke Adeseko
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Enzymatic browning is an economically important disorder that degrades organoleptic properties and prevent the consumer from purchasing fresh fruit and vegetables. Prevention and control of enzymatic browning in fruit and its product is imperative. Therefore, this study sought to investigate the catalytic effect of polyphenol oxidase (PPO) in the adverse browning of African bush mango (Irvingia gabonensis) fruit peel and pulp. PPO was isolated and purified, and its physicochemical properties, such as the effect of pH with SDS, temperature, and thermodynamic studies, which invariably led to thermal inactivation of purified PPO at 80 °C, were evaluated. The pH and temperature optima of PPO were found at 7.0 and 50, respectively. There was a gradual increase in the activity of PPO as the pH increases. However, the enzyme exhibited a higher activity at neutral pH 7.0, while enzymatic inhibition was observed at acidic region, pH 2.0. The presence of SDS at pH 5.0 downward was found to inhibit the activity of PPO from the peel and pulp of I. gabonensis. The average value of enthalpy (ΔH), entropy (ΔS), and Gibbs free energy (ΔG) obtained at 20 min of incubation and temperature 30 – 80 °C were respectively 39.93 kJ.mol-1, 431.57 J.mol-1 .K-1 and -107.99 kJ.mol-1 for peel PPO, and 37.92 kJ.mol-1, -442.51J.mol-1.K-1, and -107.22 kJ.mol-1 for pulp PPO. Thermal inactivation of PPO from I. gabonensis exhibited a reduction in catalytic activity as the temperature and duration of heat inactivation increases using catechol, reflected by an increment in k value. The half-life of PPO (t1/2) decreases as the incubation temperature increases due to the instability of the enzyme at high temperatures and was higher in pulp than peel. Both D and Z values decrease with increase in temperature. The information from this study suggests processing parameters for controlling PPO in the potential industrial application of I. gabonensis fruit in order to prolong the shelf-life of this fruit for maximum utilization.Keywords: enzymatic, browning, characterization, activity
Procedia PDF Downloads 79736 Knowledge and Utilization of Partograph among Obstetric Care Givers in Public Health Institutions of Addis Ababa, Ethiopia
Authors: Engida Yisma, Berhanu Dessalegn, Ayalew Astatkie, Nebreed Fesseha
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Background: The use of the partograph is a well-known best practice for quality monitoring of labour and subsequent prevention of obstructed and prolonged labour. However, a number of cases of obstructed labour do happen in health facilities due to poor quality of intrapartum care. Methods: A cross-sectional quantitative study assessed knowledge and utilization of partograph among obstetric care givers in public health institutions of Addis Ababa, Ethiopia using a structured interviewer administered questionnaire. The collected data was analyzed using SPSS version 16.0. Logistic regression analysis was used to identify factors associated with knowledge and use of partograph among obstetric care givers. Results: Knowledge about the partograph was fair: 189 (96.6%) of all the respondents correctly mentioned at least one component of the partograph, 104 (53.3%) correctly explained the function of alert line and 161 (82.6%) correctly explained the function of action line. The study showed that 112 (57.3%) of the obstetric care givers at public health institutions reportedly utilized partograph to monitor mothers in labour. The utilization of the partograph was significantly higher among obstetric care givers working in health centres (67.9%) compared to those working in hospitals (34.4%) [Adjusted OR = 3.63(95%CI: 1.81, 7.28)]. Conclusions: A significant percentage of obstetric care givers had fair knowledge of the partograph and why it is necessary to use it in the management of labour and over half of obstetric care givers reported use of the partograph to monitor mothers in labour. Pre-service and on-job training of obstetric care givers on the use of the partograph should be given emphasis. Mandatory health facility policy is also recommended to ensure safety of women in labour in public health facilities in Addis Ababa, Ethiopia.Keywords: partograph, knowledge, utilization, obstetric care givers, public health institutions
Procedia PDF Downloads 512735 The Effect of Technology and Artifical Intelligence on Legal Securities and Privacy Issues
Authors: Kerolis Samoul Zaghloul Noaman
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area law is the brand new access in the basket of worldwide law in the latter half of the 20 th Century. inside the last hundred and fifty years, courts and pupils advanced a consensus that, the custom is an vital supply of global law. Article 38(1) (b) of the statute of the international court of Justice identified global custom as a supply of global law. country practices and usages have a more role to play in formulating commonplace international regulation. This paper examines those country practices which may be certified to emerge as global standard law. due to the fact that, 1979 (after Moon Treaty) no hard law had been developed within the vicinity of space exploration. It attempts to link among country practices and custom in area exploration and development of standard global regulation in area activities. The paper makes use of doctrinal approach of felony research for inspecting the current questions of worldwide regulation. The paper explores exceptional worldwide prison files which include general meeting Resolutions, Treaty standards, working papers of UN, cases relating to commonplace global law and writing of jurists regarding area law and standard international law. it's far argued that, ideas such as common background of mankind, non-navy region, sovereign equality, nuclear weapon unfastened area and protection of outer area environment, etc. evolved nation practices a number of the worldwide community which can be certified to turn out to be international customary regulation.Keywords: social networks privacy issues, social networks security issues, social networks privacy precautions measures, social networks security precautions measures
Procedia PDF Downloads 9734 Numerical Investigation of Solid Subcooling on a Low Melting Point Metal in Latent Thermal Energy Storage Systems Based on Flat Slab Configuration
Authors: Cleyton S. Stampa
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This paper addresses the perspectives of using low melting point metals (LMPMs) as phase change materials (PCMs) in latent thermal energy storage (LTES) units, through a numerical approach. This is a new class of PCMs that has been one of the most prospective alternatives to be considered in LTES, due to these materials present high thermal conductivity and elevated heat of fusion, per unit volume. The chosen type of LTES consists of several horizontal parallel slabs filled with PCM. The heat transfer fluid (HTF) circulates through the channel formed between each two consecutive slabs on a laminar regime through forced convection. The study deals with the LTES charging process (heat-storing) by using pure gallium as PCM, and it considers heat conduction in the solid phase during melting driven by natural convection in the melt. The transient heat transfer problem is analyzed in one arbitrary slab under the influence of the HTF. The mathematical model to simulate the isothermal phase change is based on a volume-averaged enthalpy method, which is successfully verified by comparing its predictions with experimental data from works available in the pertinent literature. Regarding the convective heat transfer problem in the HTF, it is assumed that the flow is thermally developing, whereas the velocity profile is already fully developed. The study aims to learn about the effect of the solid subcooling in the melting rate through comparisons with the melting process of the solid in which it starts to melt from its fusion temperature. In order to best understand this effect in a metallic compound, as it is the case of pure gallium, the study also evaluates under the same conditions established for the gallium, the melting process of commercial paraffin wax (organic compound) and of the calcium chloride hexahydrate (CaCl₂ 6H₂O-inorganic compound). In the present work, it is adopted the best options that have been established by several researchers in their parametric studies with respect to this type of LTES, which lead to high values of thermal efficiency. To do so, concerning with the geometric aspects, one considers a gap of the channel formed by two consecutive slabs, thickness and length of the slab. About the HTF, one considers the type of fluid, the mass flow rate, and inlet temperature.Keywords: flat slab, heat storing, pure metal, solid subcooling
Procedia PDF Downloads 136733 Overview of the 2017 Fire Season in Amazon
Authors: Ana C. V. Freitas, Luciana B. M. Pires, Joao P. Martins
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In recent years, fire dynamics in deforestation areas of tropical forests have received considerable attention because of their relationship to climate change. Climate models project great increases in the frequency and area of drought in the Amazon region, which may increase the occurrence of fires. This study analyzes the historical record number of fire outbreaks in 2017 using satellite-derived data sets of active fire detections, burned area, precipitation, and data of the Fire Program from the Center for Weather Forecasting and Climate Studies (CPTEC/INPE). A downward trend in the number of fire outbreaks occurred in the first half of 2017, in relation to the previous year. This decrease can be related to the fact that 2017 was not an El Niño year and, therefore, the observed rainfall and temperature in the Amazon region was close to normal conditions. Meanwhile, the worst period in history for fire outbreaks began with the subsequent arrival of the dry season. September of 2017 exceeded all monthly records for number of fire outbreaks per month in the entire series. This increase was mainly concentrated in Bolivia and in the states of Amazonas, northeastern Pará, northern Rondônia and Acre, regions with high densities of rural settlements, which strongly suggests that human action is the predominant factor, aggravated by the lack of precipitation during the dry season allowing the fires to spread and reach larger areas. Thus, deforestation in the Amazon is primarily a human-driven process: climate trends may be providing additional influences.Keywords: Amazon forest, climate change, deforestation, human-driven process, fire outbreaks
Procedia PDF Downloads 122732 Lipid-Chitosan Hybrid Nanoparticles for Controlled Delivery of Cisplatin
Authors: Muhammad Muzamil Khan, Asadullah Madni, Nina Filipczek, Jiayi Pan, Nayab Tahir, Hassan Shah, Vladimir Torchilin
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Lipid-polymer hybrid nanoparticles (LPHNP) are delivery systems for controlled drug delivery at tumor sites. The superior biocompatible properties of lipid and structural advantages of polymer can be obtained via this system for controlled drug delivery. In the present study, cisplatin-loaded lipid-chitosan hybrid nanoparticles were formulated by the single step ionic gelation method based on ionic interaction of positively charged chitosan and negatively charged lipid. Formulations with various chitosan to lipid ratio were investigated to obtain the optimal particle size, encapsulation efficiency, and controlled release pattern. Transmission electron microscope and dynamic light scattering analysis demonstrated a size range of 181-245 nm and a zeta potential range of 20-30 mV. Compatibility among the components and the stability of formulation were demonstrated with FTIR analysis and thermal studies, respectively. The therapeutic efficacy and cellular interaction of cisplatin-loaded LPHNP were investigated using in vitro cell-based assays in A2780/ADR ovarian carcinoma cell line. Additionally, the cisplatin loaded LPHNP exhibited a low toxicity profile in rats. The in-vivo pharmacokinetics study also proved a controlled delivery of cisplatin with enhanced mean residual time and half-life. Our studies suggested that the cisplatin-loaded LPHNP being a promising platform for controlled delivery of cisplatin in cancer therapy.Keywords: cisplatin, lipid-polymer hybrid nanoparticle, chitosan, in vitro cell line study
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