Search results for: experimental method
Commenced in January 2007
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Edition: International
Paper Count: 23871

Search results for: experimental method

11541 Design of a Compact Microstrip Patch Antenna for LTE Applications by Applying FDSC Model

Authors: Settapong Malisuwan, Jesada Sivaraks, Peerawat Promkladpanao, Nattakit Suriyakrai, Navneet Madan

Abstract:

In this paper, a compact microstrip patch antenna is designed for mobile LTE applications by applying the frequency-dependent Smith-Chart (FDSC) model. The FDSC model is adopted in this research to reduce the error on the frequency-dependent characteristics. The Ansoft HFSS and various techniques is applied to meet frequency and size requirements. The proposed method within this research is suitable for use in computer-aided microstrip antenna design and RF integrated circuit (RFIC) design.

Keywords: frequency-dependent, smith-chart, microstrip, antenna, LTE, CAD

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11540 Formulation and Characterization of Antimicrobial Herbal Mouthwash from Some Herbal Extracts for Treatment of Periodontal Diseases

Authors: Reenu Yadav, Abhay Asthana, S. K. Yadav

Abstract:

Purpose: The aim of the present work was to develop an oral gel for brushing with an antimicrobial activity which will cure/protect from various periodontal diseases such as periodontitis, gingivitis, and pyorrhea. Methods: Plant materials procured from local suppliers, extracted and standardized. Screening of antimicrobial activity was carried out with the help of disk diffusion method. The gel was formulated by dried extracts of Beautea monosperma and Cordia obliquus. Gels were evaluated on various parameters and standardization of the formulation was performed. The release of drugs was studied in pH 6.8 using a mastication device.Total phenolic and flavonoid contents were estimated by folin-Ciocalteu and aluminium chloride method, and stability studies were performed (40°C and RH 75% ± 5% for 90 days) to assess the effect of temperature and humidity on the concentration of phenolic and flavonoid contents. The results of accelerated stability conditions were compared with that of samples kept at controlled conditions (RT). The control samples were kept at room temperature (25°C, 35% RH for 180 days). Results: Results are encouraging; extracts possess significant antimicrobial activity at very low concentration (15µg/disc, 20µg/disc and 15 µg/ disc) on oral pathogenic bacteria. The formulation has optimal characteristics, as well as has a pleasant appearance, fragrance, texture, and taste, is highly acceptable by the volunteers. The diffusion coefficient values ranged from 0.6655 to 0.9164. Since the R values of korsmayer papas were close to 1, Drug release from formulation follows matrix diffusion kinetics. Hence, diffusion was the mechanism of the drug release. Formulation follows non-Fickian transport mechanism. Most Formulations released 50 % of their contents within 25-30 minutes. Results obtained from the accelerated stability studies are indicative of a slight reduction in flavonoids and phenolic contents with time on long time storage. When measured degradation under ambient conditions, degradation was significantly lower than in accelerated stability study. Conclusion: Plant extracts possess compounds with antimicrobial properties can be used as. Developed formulation will cure/protect from various periodontal diseases. Further development and evaluations oral gel including the isolated compounds on the commercial scale and their clinical and toxicological studies are the future challenges.

Keywords: herbal gel, dental care, ambient conditions, commercial scale

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11539 Evaluating Gallein Dye as a Beryllium Indicator

Authors: Elise M. Shauf

Abstract:

Beryllium can be found naturally in some fruits and vegetables (carrots, garden peas, kidney beans, pears) at very low concentrations, but is typically not clinically significant due to the low-level exposure and limited absorption of beryllium by the stomach and intestines. However, acute or chronic beryllium exposure can result in harmful toxic and carcinogenic biological effects. Beryllium can be both a workplace hazard and an environmental pollutant, therefore determining the presence of beryllium at trace levels can be essential to protect workers as well as the environment. Analysis of gallein, C₂₀H₁₂O₇, to determine if it is usable as a fluorescent dye for beryllium detection. The primary detection method currently in use includes hydroxybenzoquinoline sulfonates (HBQS), for which alternative indicators are desired. Unfortunately, gallein does not have the desired aspects needed as a dye for beryllium detection due to the peak shift properties.

Keywords: beryllium detection, fluorescent, gallein dye, indicator, spectroscopy

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11538 Phishing Attacks Facilitated by Open Source Intelligence

Authors: Urva Maryam

Abstract:

The information has become an important asset to the current cosmos. Globally, various tactics are being observed to confine the spread of information as it makes people vulnerable to security attacks. Open Source Intelligence (OSINT) is a publicly available source that has disseminated information about users or websites, companies, and various organizations. This paper focuses on the quantitative method of exploring various OSINT tools that reveal public information of personals. This information could further facilitate phishing attacks. Phishing attacks can be launched on email addresses, open ports, and unsecure web-surfing. This study allows to analyze the information retrieved from OSINT tools, i.e. theHarvester, and Maltego that can be used to send phishing attacks to individuals.

Keywords: e-mail spoofing, Maltego, OSINT, phishing, spear phishing, theHarvester

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11537 Applicability of Linearized Model of Synchronous Generator for Power System Stability Analysis

Authors: J. Ritonja, B. Grcar

Abstract:

For the synchronous generator simulation and analysis and for the power system stabilizer design and synthesis a mathematical model of synchronous generator is needed. The model has to accurately describe dynamics of oscillations, while at the same time has to be transparent enough for an analysis and sufficiently simplified for design of control system. To study the oscillations of the synchronous generator against to the rest of the power system, the model of the synchronous machine connected to an infinite bus through a transmission line having resistance and inductance is needed. In this paper, the linearized reduced order dynamic model of the synchronous generator connected to the infinite bus is presented and analysed in details. This model accurately describes dynamics of the synchronous generator only in a small vicinity of an equilibrium state. With the digression from the selected equilibrium point the accuracy of this model is decreasing considerably. In this paper, the equations’ descriptions and the parameters’ determinations for the linearized reduced order mathematical model of the synchronous generator are explained and summarized and represent the useful origin for works in the areas of synchronous generators’ dynamic behaviour analysis and synchronous generator’s control systems design and synthesis. The main contribution of this paper represents the detailed analysis of the accuracy of the linearized reduced order dynamic model in the entire synchronous generator’s operating range. Borders of the areas where the linearized reduced order mathematical model represents accurate description of the synchronous generator’s dynamics are determined with the systemic numerical analysis. The thorough eigenvalue analysis of the linearized models in the entire operating range is performed. In the paper, the parameters of the linearized reduced order dynamic model of the laboratory salient poles synchronous generator were determined and used for the analysis. The theoretical conclusions were confirmed with the agreement of experimental and simulation results.

Keywords: eigenvalue analysis, mathematical model, power system stability, synchronous generator

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11536 A Study of Financial Literacy among Undergraduates

Authors: Prasansha Kumari

Abstract:

Financial Literacy is the possession of knowledge and understanding of financial matters. Financial Literacy often entails the knowledge of properly making decisions pertaining to certain personal financial areas like real estate, insurance investing, and savings. This paper intends to identify and analyze the financial knowledge among university undergraduates by using 200 undergraduates in four faculties of University of Kelaniya, Sri Lanka. Collected data will be analyzed by descriptive research method using SPSS package. Expected outcomes are considerable percentage of undergraduates have basic knowledge on financial matters while it has a law percentage for advanced financial literacy among undergraduates. Students from faculty of Commerce and Management and Science have good understanding about financial matters than undergraduates in other two faculties

Keywords: advanced finance, undergraduates, financial literacy, savings

Procedia PDF Downloads 331
11535 Effect of Impact Angle on Erosive Abrasive Wear of Ductile and Brittle Materials

Authors: Ergin Kosa, Ali Göksenli

Abstract:

Erosion and abrasion are wear mechanisms reducing the lifetime of machine elements like valves, pump and pipe systems. Both wear mechanisms are acting at the same time, causing a “Synergy” effect, which leads to a rapid damage of the surface. Different parameters are effective on erosive abrasive wear rate. In this study effect of particle impact angle on wear rate and wear mechanism of ductile and brittle materials was investigated. A new slurry pot was designed for experimental investigation. As abrasive particle, silica sand was used. Particle size was ranking between 200-500 µm. All tests were carried out in a sand-water mixture of 20% concentration for four hours. Impact velocities of the particles were 4,76 m/s. As ductile material steel St 37 with Brinell Hardness Number (BHN) of 245 and quenched St 37 with 510 BHN was used as brittle material. After wear tests, morphology of the eroded surfaces were investigated for better understanding of the wear mechanisms acting at different impact angles by using optical microscopy and Scanning Electron Microscope. The results indicated that wear rate of ductile material was higher than brittle material. Maximum wear was observed by ductile material at a particle impact angle of 300. On the contrary wear rate increased by brittle materials by an increase in impact angle and reached maximum value at 450. High amount of craters were detected after observation on ductile material surface Also plastic deformation zones were detected, which are typical failure modes for ductile materials. Craters formed by particles were deeper according to brittle material worn surface. Amount of craters decreased on brittle material surface. Microcracks around craters were detected which are typical failure modes of brittle materials. Deformation wear was the dominant wear mechanism on brittle material. At the end it is concluded that wear rate could not be directly related to impact angle of the hard particle due to the different responses of ductile and brittle materials.

Keywords: erosive wear, particle impact angle, silica sand, wear rate, ductile-brittle material

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11534 Process of Analysis, Evaluation and Verification of the 'Real' Redevelopment of the Public Open Space at the Neighborhood’s Stairs: Case Study of Serres, Greece

Authors: Ioanna Skoufali

Abstract:

The present study is directed towards adaptation to climate change closely related to the phenomenon of the urban heat island (UHI). This issue is widespread and common to different urban realities, but particularly in Mediterranean cities that are characterized by dense urban. The attention of this work of redevelopment of the open space is focused on mitigation techniques aiming to solve local problems such as microclimatic parameters and the conditions of thermal comfort in summer, related to urban morphology. This quantitative analysis, evaluation, and verification survey involves the methodological elaboration applied in a real study case by Serres, through the experimental support of the ENVImet Pro V4.1 and BioMet software developed: i) in two phases concerning the anteoperam (phase a1 # 2013) and the post-operam (phase a2 # 2016); ii) in scenario A (+ 25% of green # 2017). The first study tends to identify the main intervention strategies, namely: the application of cool pavements, the increase of green surfaces, the creation of water surface and external fans; moreover, it obtains the minimum results achieved by the National Program 'Bioclimatic improvement project for public open space', EPPERAA (ESPA 2007-2013) related to the four environmental parameters illustrated below: the TAir = 1.5 o C, the TSurface = 6.5 o C, CDH = 30% and PET = 20%. In addition, the second study proposes a greater potential for improvement than postoperam intervention by increasing the vegetation within the district towards the SW/SE. The final objective of this in-depth design is to be transferable in homogeneous cases of urban regeneration processes with obvious effects on the efficiency of microclimatic mitigation and thermal comfort.

Keywords: cool pavements, microclimate parameters (TAir, Tsurface, Tmrt, CDH), mitigation strategies, outdoor thermal comfort (PET & UTCI)

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11533 Chemical Compositon and Antimicrobial Activity of Daucus aristidis Coss. Essential Oil in Pre-Flowering Stage from Algeria

Authors: M. Lamamra, H. Laouer, A. Adjaoud, Sahli Farida

Abstract:

Essential oils can have significant antimicrobial activities and can successfully replace antibiotics that show their ineffectiveness against resistant germs. The chemical composition of the essential oil obtained by hydrodistillation from the aerial part of Daucus aristidis (Apiaceae) at the pre-flowering stage was investigated for the first time, by GC and GC-MS and evaluated for in vitro antimicrobial activity by the disk diffusion method. The Main components of D. aristidis oil were α-pinene (20.13%), cedrol (20.11%), and E- asarone (18.53%). The oil exhibited an antibacterial activity against almost strains tested except for Klebsiella pneumoniae ATCC 700603 K6 and Enterococcus faecalis ATCC 49452, the oil of D. aristidis had no activity against all fungi tested.

Keywords: α-pinene, antimicrobial activity, Daucus aridtidis, essential oil

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11532 Against Language Disorder: A Way of Reading Dialects in Yan Lianke’s Novels

Authors: Thuy Hanh Nguyen Thi

Abstract:

By the method of deep reading and text analysis, this article will analyze the use and creation of dialects as a way of demonstrating Yan Lianke's creative stance. This article indicates that this is the writer’s narrative strategy in a fight against aphasia, a language disorder of Chinese people and culture, demonstrating a sense of return to folklore and marks his own linguistic style. In terms of verbal text, the dialect in the Yan Lianke’s novels manifested through the use of words, sentences and dialects. There are two types of dialects that exist in Yan Lianke’s novels: the current dialect system and the particular dialect system of Pa Lau world created by the writer himself in order to enrich the vocabulary of Han Chinese.

Keywords: Yan Lianke , aphasia, dialect, Pa Lou world

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11531 Magnitude of Infection and Associated factor in Open Tibial Fractures Treated Operatively at Addis Ababa Burn Emergency and Trauma Center April, 2023

Authors: Tuji Mohammed Sani

Abstract:

Back ground: An open tibial fracture is an injury where the fractured bone directly communicates with the outside environment. Due to the specific anatomical features of the tibia (limited soft tissue coverage), more than quarter of its fractures are classified as open, representing the most common open long-bone injuries. Open tibial fractures frequently cause significant bone comminution, periosteal stripping, soft tissue loss, contamination and are prone to bacterial entry with biofilm formation, which increases the risk of deep bone infection. Objective: The main objective of the study was to determine Prevalence of infection and its associated factors in surgically treated open tibial fracture in Addis Ababa Burn Emergency and Trauma (AaBET) center. Method: A facility based retrospective cross-sectional study was conducted among patient treated for open tibial fracture at AaBET center from September 2018 to September 2021. The data was collected from patient’s chart using structured data collection form, and Data was entered and analyzed using SPSS version 26. Bivariable and multiple binary logistic regression were fitted. Multicollinearity was checked among candidate variables using variance inflation factor and tolerance, which were less than 5 and greater than 0.2, respectively. Model adequacy were tested using Hosmer-Lemeshow goodness of fitness test (P=0.711). AOR at 95% CI was reported, and P-value < 0.05 was considered statistically significant. Result: This study found that 33.9% of the study participants had an infection. Initial IV antibiotic time (AOR=2.924, 95% CI:1.160- 7.370) and time of wound closure from injury (AOR=3.524, 95% CI: 1.798-6.908), injury to admission time (AOR=2.895, 95% CI: 1.402 – 5.977). and definitive fixation method (AOR=0.244, 95% CI: 0.113 – 0.4508) were the factors found to have a statistically significant association with the occurrence of infection. Conclusion: The rate of infection in open tibial fractures indicates that there is a need to improve the management of open tibial fracture treated at AaBET center. Time from injury to admission, time from injury to first debridement, wound closure time, and initial Intra Venous antibiotic time from the injury are an important factor that can be readily amended to improve the infection rate. Whether wound closed before seven days or not were more important factor associated with occurrences of infection.

Keywords: infection, open tibia, fracture, magnitude

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11530 Investigation the Effect of Nano-Alumina Particles on Physical Adsorption Property of Acrylic Fiber

Authors: Mehdi Ketabchi, Shamsollah Alijanlou

Abstract:

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

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

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11529 Rapid Plasmonic Colorimetric Glucose Biosensor via Biocatalytic Enlargement of Gold Nanostars

Authors: Masauso Moses Phiri

Abstract:

Frequent glucose monitoring is essential to the management of diabetes. Plasmonic enzyme-based glucose biosensors have the advantages of greater specificity, simplicity and rapidity. The aim of this study was to develop a rapid plasmonic colorimetric glucose biosensor based on biocatalytic enlargement of AuNS guided by GOx. Gold nanoparticles of 18 nm in diameter were synthesized using the citrate method. Using these as seeds, a modified seeded method for the synthesis of monodispersed gold nanostars was followed. Both the spherical and star-shaped nanoparticles were characterized using ultra-violet visible spectroscopy, agarose gel electrophoresis, dynamic light scattering, high-resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy. The feasibility of a plasmonic colorimetric assay through growth of AuNS by silver coating in the presence of hydrogen peroxide was investigated by several control and optimization experiments. Conditions for excellent sensing such as the concentration of the detection solution in the presence of 20 µL AuNS, 10 mM of 2-(N-morpholino) ethanesulfonic acid (MES), ammonia and hydrogen peroxide were optimized. Using the optimized conditions, the glucose assay was developed by adding 5mM of GOx to the solution and varying concentrations of glucose to it. Kinetic readings, as well as color changes, were observed. The results showed that the absorbance values of the AuNS were blue shifting and increasing as the concentration of glucose was elevated. Control experiments indicated no growth of AuNS in the absence of GOx, glucose or molecular O₂. Increased glucose concentration led to an enhanced growth of AuNS. The detection of glucose was also done by naked-eye. The color development was near complete in ± 10 minutes. The kinetic readings which were monitored at 450 and 560 nm showed that the assay could discriminate between different concentrations of glucose by ± 50 seconds and near complete at ± 120 seconds. A calibration curve for the qualitative measurement of glucose was derived. The magnitude of wavelength shifts and absorbance values increased concomitantly with glucose concentrations until 90 µg/mL. Beyond that, it leveled off. The lowest amount of glucose that could produce a blue shift in the localized surface plasmon resonance (LSPR) absorption maxima was found to be 10 – 90 µg/mL. The limit of detection was 0.12 µg/mL. This enabled the construction of a direct sensitivity plasmonic colorimetric detection of glucose using AuNS that was rapid, sensitive and cost-effective with naked-eye detection. It has great potential for transfer of technology for point-of-care devices.

Keywords: colorimetric, gold nanostars, glucose, glucose oxidase, plasmonic

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11528 Response Surface Methodology to Supercritical Carbon Dioxide Extraction of Microalgal Lipids

Authors: Yen-Hui Chen, Terry Walker

Abstract:

As the world experiences an energy crisis, investing in sustainable energy resources is a pressing mission for many countries. Microalgae-derived biodiesel has attracted intensive attention as an important biofuel, and microalgae Chlorella protothecoides lipid is recognized as a renewable source for microalgae-derived biodiesel production. Supercritical carbon dioxide (SC-CO₂) is a promising green solvent that may potentially substitute the use of organic solvents for lipid extraction; however, the efficiency of SC-CO₂ extraction may be affected by many variables, including temperature, pressure and extraction time individually or in combination. In this study, response surface methodology (RSM) was used to optimize the process parameters, including temperature, pressure and extraction time, on C. protothecoides lipid yield by SC-CO₂ extraction. A second order polynomial model provided a good fit (R-square value of 0.94) for the C. protothecoides lipid yield. The linear and quadratic terms of temperature, pressure and extraction time—as well as the interaction between temperature and pressure—showed significant effects on lipid yield during extraction. The optimal lipid yield from the model was predicted as the temperature of 59 °C, the pressure of 350.7 bar and the extraction time 2.8 hours. Under these conditions, the experimental lipid yield (25%) was close to the predicted value. The principal fatty acid methyl esters (FAME) of C. protothecoides lipid-derived biodiesel were oleic acid methyl ester (60.1%), linoleic acid methyl ester (18.6%) and palmitic acid methyl ester (11.4%), which made up more than 90% of the total FAMEs. In summary, this study indicated that RSM was useful to characterize the optimization the SC-CO₂ extraction process of C. protothecoides lipid yield, and the second-order polynomial model could be used for predicting and describing the lipid yield very well. In addition, C. protothecoides lipid, extracted by SC-CO₂, was suggested as a potential candidate for microalgae-derived biodiesel production.

Keywords: Chlorella protothecoides, microalgal lipids, response surface methodology, supercritical carbon dioxide extraction

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11527 Determination of the Economic Planning Depth for Assembly Process Planning

Authors: A. Kampker, P. Burggräf, Y. Bäumers

Abstract:

In order to be competitive, companies have to reduce their production costs while meeting increasing quality requirements. Therefore, companies try to plan their assembly processes as detailed as possible. However, increasing product individualization leading to a higher number of variants, smaller batch sizes and shorter product life cycles raise the question to what extent the effort of detailed planning is still justified. An important approach in this field of research is the concept of determining the economic planning depth for assembly process planning based on production specific influencing factors. In this paper, first solution hypotheses as well as a first draft of the resulting method will be presented.

Keywords: assembly process planning, economic planning depth, planning benefit, planning effort

Procedia PDF Downloads 492
11526 Improving Engagement: Dental Veneers, a Qualitative Analysis of Posts on Instagram

Authors: Matthew Sedgwick

Abstract:

Introduction: Social media continues to grow in popularity and Instagram is one of the largest platforms available. It provides an invaluable method of communication between health care professionals and patients. Both patients and dentists can benefit from seeing clinical cases posted by other members of the profession. It can prompt discussion about how the outcome was achieved and showcases what is possible with the right techniques and planning. This study aimed to identify what people were posting about the topic ‘veneers’ and inform health care professionals as to what content had the most engagement and make recommendations as to how to improve the quality of social media posts. Design: 150 consecutive posts for the search term ‘veneers’ were analyzed retrospectively between 21st October 2021 to 31st October 2021. Non-English language posts duplicated posts, and posts not about dental veneers were excluded. After exclusions were applied, 80 posts were included in the study for analysis. The content of the posts was analyzed and coded and the main themes were identified. The number of comments, likes and views were also recorded for each post. Results: The themes were: before and after treatment, cost, dental training courses, treatment process and trial smiles. Dentists were the most common posters of content (82.5%) and it was interesting to note that there were no patients who posted about treatment in this sample. The main type of media was photographs (93.75%) compared to video (6.25%). Videos had an average of 45,541 views and more comments and likes than the average for photographs. The average number of comments and likes per post were 20.88 and 761.58, respectively. Conclusion: Before and after photographs were the most common finding as this is how dentists showcase their work. The study showed that videos showing the treatment process had more engagement than photographs. Dentists should consider making video posts showing the patient journey, including before and after veneer treatment, as this can result in more potential patients and colleagues viewing the content. Video content could help dentists distinguish their posts from others as it can also be used across other platforms such as TikTok or Facebook reaching a wider audience. More informative posts about how the result has shown are achieved required, including potential costs. This will help increase transparency regarding this treatment method, including the financial and potential biological cost to teeth. As a result, this will improve patient understanding and become an invaluable adjunct in informed consent.

Keywords: content analysis, dental veneers, Instagram, social media

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11525 Speed Control of Hybrid Stepper Motor by Using Adaptive Neuro-Fuzzy Controller

Authors: Talha Ali Khan

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This paper presents an adaptive neuro-fuzzy interference system (ANFIS), which is applied to a hybrid stepper motor (HSM) to regulate its speed. The dynamic response of the HSM with the ANFIS controller is studied during the starting process and under different load disturbance. The effectiveness of the proposed controller is compared with that of the conventional PI controller. The proposed method solves the problem of nonlinearities and load changes of the HSM drives. The proposed controller ensures fast and precise dynamic response with an excellent steady state performance. Matlab/Simulink program is used for this dynamic simulation study.

Keywords: stepper motor, hybrid, ANFIS, speed control

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11524 Hypoglycemic and Hypolipidemic Effects of Aqueous Flower Extract from Nyctanthes arbor-tristis L.

Authors: Brahmanage S. Rangika, Dinithi C. Peiris

Abstract:

Boiled Aqueous Flower Extract (AFE) of Nyctanthes arbor-tristis L. (Family: Oleaceae) is used in traditional Sri Lankan medicinal system to treat diabetes. However, this is not scientifically proven and the mechanisms by which the flowers reduce diabetes have not been investigated. The present study was carried out to examine the hypoglycemic potential and toxicity effects of aqueous flower extract of N. arbor-tristis. AFE was prepared and mice were treated orally either with 250, 500, and 750 mg/kg of AFE or distilled water (Control). Fasting and random blood glucose levels were determined. In addition, the toxicity of AFE was determined using chronic oral administration. In normoglycemic mice, mid dose (500mg/kg) of AFE significantly (p < 0.01) reduced fasting blood glucose levels by 49% at 4h post treatment. Further, 500mg/kg of AFE significantly (p < 0.01) lowered random blood glucose level of non-fasted normoglycemic mice. AFE significantly lowered total cholesterol and triglyceride levels while increasing the HDL levels in the serum. Further, AFE significantly inhibited the glucose absorption from the lumen of the intestine and it increases the diaphragm uptake of glucose. Alpha-amylase inhibitory activity was also evident. However, AFE did not induce any overt signs of toxicity or hepatotoxicity. There were no adverse effects on food and water intake and body weight of mice during the experimental period. It can be concluded that AFE of N. arbor-tristis posses safe oral anti diabetic potentials mediated via multiple mechanisms. Results of the present study scientifically proved the claims made about the uses of N. arbor-tristis in the treatment of diabetes mellitus in traditional Sri Lankan medicinal system. Further, flowers can also be used for as a remedy to improve blood lipid profile.

Keywords: aqueous extract, hypoglycemic hypolipidemic, Nyctanthes arbor-tristis flowers, hepatotoxicity

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11523 Surface Modified Core–Shell Type Lipid–Polymer Hybrid Nanoparticles of Trans-Resveratrol, an Anticancer Agent, for Long Circulation and Improved Efficacy against MCF-7 Cells

Authors: M. R. Vijayakumar, K. Priyanka, Ramoji Kosuru, Lakshmi, Sanjay Singh

Abstract:

Trans resveratrol (RES) is a non-flavonoid poly-phenolic compound proved for its therapeutic and preventive effect against various types of cancer. However, the practical application of RES in cancer treatment is limited because of its higher dose (up to 7.5 g/day in humans), low biological half life, rapid metabolism and faster elimination in mammals. PEGylated core-shell type lipid polymer hybrid nanoparticles are the novel drug delivery systems for long circulation and improved anti cancer effect of its therapeutic payloads. Therefore, the main objective of this study is to extend the biological half life (long circulation) and improve the therapeutic efficacy of RES through core shell type of nanoparticles. D-α-tocopheryl polyethylene glycol 1000 succinate (vitamin E TPGS), a novel surfactant is applied for the preparation of PEGylated lipid polymer hybrid nanoparticles. The prepared nanoparticles were evaluated by various state of the art techniques such as dynamic light scattering (DLS) technique for particle size and zeta potential, TEM for shape, differential scanning calorimetry (DSC) for interaction analysis and XRD for crystalline changes of drug. Entrapment efficiency and invitro drug release were determined by ultracentrifugation method and dialysis bag method, respectively. Cancer cell viability studies were performed by MTT assay, respectively. Pharmacokinetic studies after i.v administration were performed in sprague dawley rats. The prepared NPs were found to be spherical in shape with smooth surfaces. Particle size and zeta potential of prepared NPs were found to be in the range of 179.2±7.45 to 266.8±9.61 nm and -0.63 to -48.35 mV, respectively. DSC revealed absence of potential interaction. XRD study revealed presence of amorphous form in nanoparticles. Entrapment efficiency was found to be 83.7 % and drug release was found to be in controlled manner. MTT assay showed low MEC and pharmacokinetic studies showed higher AUC of nanoformulaition than its pristine drug. All these studies revealed that the RES loaded PEG modified core-shell type lipid polymer hybrid nanoparticles can be an alternative tool for chemopreventive and therapeutic application of RES in cancer.

Keywords: trans resveratrol, cancer nanotechnology, long circulating nanoparticles, bioavailability enhancement, core shell nanoparticles, lipid polymer hybrid nanoparticles

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11522 Bowen Ratio in Western São Paulo State, Brazil

Authors: Elaine Cristina Barboza, Antonio Jaschke Machado

Abstract:

This paper discusses micrometeorological aspects of the urban climate in three cities in Western São Paulo State: Presidente Prudente, Assis, and Iepê. Particular attention is paid to the method used to estimate the components of the energy balance at the surface. Estimates of convective fluxes showed that the Bowen ratio was an indicator of the local climate and that its magnitude varied between 0.3 and 0.7. Maximum values for the Bowen ratio occurred earlier in Iepê (11:00 am) than in Presidente Prudente (4:00 pm). The results indicate that the Bowen ratio is modulated by the radiation balance at the surface and by different clusters of vegetation.

Keywords: Bowen ratio, medium-sized cities, surface energy balance, urban climate

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11521 Downtime Estimation of Building Structures Using Fuzzy Logic

Authors: M. De Iuliis, O. Kammouh, G. P. Cimellaro, S. Tesfamariam

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Community Resilience has gained a significant attention due to the recent unexpected natural and man-made disasters. Resilience is the process of maintaining livable conditions in the event of interruptions in normally available services. Estimating the resilience of systems, ranging from individuals to communities, is a formidable task due to the complexity involved in the process. The most challenging parameter involved in the resilience assessment is the 'downtime'. Downtime is the time needed for a system to recover its services following a disaster event. Estimating the exact downtime of a system requires a lot of inputs and resources that are not always obtainable. The uncertainties in the downtime estimation are usually handled using probabilistic methods, which necessitates acquiring large historical data. The estimation process also involves ignorance, imprecision, vagueness, and subjective judgment. In this paper, a fuzzy-based approach to estimate the downtime of building structures following earthquake events is proposed. Fuzzy logic can integrate descriptive (linguistic) knowledge and numerical data into the fuzzy system. This ability allows the use of walk down surveys, which collect data in a linguistic or a numerical form. The use of fuzzy logic permits a fast and economical estimation of parameters that involve uncertainties. The first step of the method is to determine the building’s vulnerability. A rapid visual screening is designed to acquire information about the analyzed building (e.g. year of construction, structural system, site seismicity, etc.). Then, a fuzzy logic is implemented using a hierarchical scheme to determine the building damageability, which is the main ingredient to estimate the downtime. Generally, the downtime can be divided into three main components: downtime due to the actual damage (DT1); downtime caused by rational and irrational delays (DT2); and downtime due to utilities disruption (DT3). In this work, DT1 is computed by relating the building damageability results obtained from the visual screening to some already-defined components repair times available in the literature. DT2 and DT3 are estimated using the REDITM Guidelines. The Downtime of the building is finally obtained by combining the three components. The proposed method also allows identifying the downtime corresponding to each of the three recovery states: re-occupancy; functional recovery; and full recovery. Future work is aimed at improving the current methodology to pass from the downtime to the resilience of buildings. This will provide a simple tool that can be used by the authorities for decision making.

Keywords: resilience, restoration, downtime, community resilience, fuzzy logic, recovery, damage, built environment

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11520 Improvement of Fatigue and Fatigue Corrosion Resistances of Turbine Blades Using Laser Cladding

Authors: Sami I. Jafar, Sami A. Ajeel, Zaman A. Abdulwahab

Abstract:

The turbine blades used in electric power plants are made of low alloy steel type 52. These blades will be subjected to fatigue and also at other times to fatigue corrosion with aging time. Due to their continuous exposure to cyclic rotational stresses in corrosive steam environments, The current research aims to deal with this problem using the laser cladding method for low alloy steel type 52, which works to re-compose the metallurgical structure and improve the mechanical properties by strengthening the resulting structure, which leads to an increase in fatigue and wears resistance, therefore, an increase in the life of these blades is observed.

Keywords: fatigue, fatigue corrosion, turbine blades, laser cladding

Procedia PDF Downloads 184
11519 Teaching Academic Vocabulary: A Recent and Old Approach

Authors: Sara Fine-Meltzer

Abstract:

An obvious, but ill-addressed hindrance to reading comprehension in academic English is poor vocabulary. Unfortunately, dealing with the problem is usually delayed until university entrance. It is the contention of this paper that the chore should be confronted much earlier and by using a very old-fashioned method. This presentation is accompanied by vocabulary lists for advanced level university students with explanations concerning the content and justification for the 500-word lists: how they change over time in accordance with evolving styles of academic writing. There are also sample quizzes and methods to ensure that the words are “absorbed” over time. There is a discussion of other vocabulary acquisition methods and conclusions drawn from the drawbacks of such methods. The paper concludes with the rationale for beginning the study of “academic” vocabulary earlier than is generally acceptable.

Keywords: academic vocabulary, old-fashioned methods, quizzes, vocabulary lists

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11518 Ta-doped Nb2O5: Synthesis and Photocatalytic Activity

Authors: Mahendrasingh J. Pawar, M. D. Gaoner

Abstract:

Ta-doped Nb2O5 (Ta content 0.5-2% mole fraction) nanoparticles in the range of 20-40 nm were synthesized by combustion technique. The crystalline phase, morphology and size of the nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and UV-vis spectroscopy. The specific surface area of the nanoparticles was measured by nitrogen adsorption (BET analysis). The undoped Nb2O5 nanoparticles were found to have the particles size in the range of 50−80 nm. The photocatalytic performance of the samples was characterized by degrading 20 mg/L toluene under UV−Vis irradiation. The results show that the Ta-doped Nb2O5 nanoparticles exhibit a significant increase in photocatalytic performance over the undoped Nb2O5 nanoparticles, and the Nb2O5 nanoparticles doped with 1.5% Ta and calcined at 450°C show the best photocatalytic performance.

Keywords: Nb2O5, Ta-doped Nb2O5, photodegradation of Toluene, combustion method

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11517 Patient Satisfaction Measurement Using Face-Q for Non-Incisional Double-Eyelid Blepharoplasty with Modified Single-Knot Continuous Buried Suture Technique

Authors: Kwei Huan Liw, Sashi B. Darshan

Abstract:

Background: Double eyelid surgery has become one of the most sought-after aesthetic procedures among Asians. Many surgeons perform surgical blepharoplasty and various other methods of non-incisional blepharoplasty. Face-Q is a validated method of measuring patient satisfaction for facial aesthetic procedures. Here we have analyzed the overall eye satisfaction score, the upper eyelid appraisal score and the adverse effect on eyes score Methods: 274 patients (548 eyes), aged between 18 to 40 years old, were recruited from 2015-2018. Each patient underwent a non-incisional double-eyelid blepharoplasty using a single-knotted continuous buried suture. 3 – 5 stab incisions were made depending on the upper eyelid size. A needle loaded with 7-0 nylon is passed from the lateral most wound through the dermis and the conjunctiva in an alternate fashion into the remaining stab wounds. The suture is then tunneled back laterally in the deeper dermis and knotted securely with the suture end. The knot is then buried within the orbicularis oculi muscle. Each patient was required to fill the Face-Q questionnaire before the procedure and 2 weeks post procedure. The results are described based on the percentage of the maximum achievable score. Patients were reviewed after 12 to 18 months to assess the long-term outcome. Results: The overall eye satisfaction score demonstrated a high level of post-operative satisfaction (97.85%), compared to 27.32% pre-operatively. The appraisal of upper eyelid scores showed drastic improvement in perception post-operatively (95.31%) compared to 21.44% pre-operatively. Adverse effect on eyes score showed a very low post-operative complication rate (0.4%) The long-term follow-up showed 6 cases that had developed asymmetrical folds. Only 1 patient agreed for revision surgery. The other 5 patients were still satisfied with the outcome and were not keen for revision surgery. None of the cases had loosening of knots. Conclusion: Modified single-knot continuous buried suture technique is a simple and non-invasive method to create aesthetically pleasing non-surgical double-eyelids, which has long-term effects. Proper patient selection is crucial and good surgical technique is required to achieve a desirable outcome.

Keywords: blepharoplasty, double-eyelid, face-Q, non-incisional

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11516 Numerical Model Validation Using Durbin Method

Authors: H. Al-Hajeri

Abstract:

The computation of the effectiveness of turbulence enhancement surface features, such as ribs as means of promoting mixing and hence heat transfer, has attracted the continued attention of the engineering community. In this study, the simulation of a three-dimensional cooling passage is carried out employing a number of turbulence models including Durbin model. The cooling passage consists of a square section duct whose upper and lower surfaces feature staggered cuboid ribs. The main objective of this paper is to provide comparisons of the performance of the v2-f model against other established turbulence models as implemented in the commercial CFD code Ansys Fluent. The present study demonstrates that the v2-f model can successfully capture the isothermal air flow phenomena in flow over obstacles.

Keywords: CFD, cooling passage, Durbin model, turbulence model

Procedia PDF Downloads 494
11515 Formation Mechanism of Macroporous Cu/CuSe and Its Application as Electrocatalyst for Methanol Oxidation Reaction

Authors: Nabi Ullah

Abstract:

The single-step solvothermal method is used to prepare Cu/CuSe as an electrocatalyst for methanol electro-oxidation reaction (MOR). 1,3-butane-diol is selected as a reaction medium, whose viscosity and complex formation with Cu(II) ions dictate the catalyst morphology. The catalyst has a macroporous structure, which is composed of nanoballs with a high purity, crystallinity, and uniform morphology. The electrocatalyst is excellent for MOR, as it delivers a current density of 37.28 mA/mg at a potential of 0.6 V (vs Ag/AgCl) in the electrolyte of 1 M KOH and 0.75 M methanol at a 50 mV/s scan rate under conditions of cyclic voltammetry. The catalyst also shows good stability for 3600 s with negligible charge transfer resistance and a high electrochemical active surface area (ECSA) value of 0.100 mF/cm².

Keywords: MOR, copper selenide, electocatalyst, energy application

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11514 Split Monotone Inclusion and Fixed Point Problems in Real Hilbert Spaces

Authors: Francis O. Nwawuru

Abstract:

The convergence analysis of split monotone inclusion problems and fixed point problems of certain nonlinear mappings are investigated in the setting of real Hilbert spaces. Inertial extrapolation term in the spirit of Polyak is incorporated to speed up the rate of convergence. Under standard assumptions, a strong convergence of the proposed algorithm is established without computing the resolvent operator or involving Yosida approximation method. The stepsize involved in the algorithm does not depend on the spectral radius of the linear operator. Furthermore, applications of the proposed algorithm in solving some related optimization problems are also considered. Our result complements and extends numerous results in the literature.

Keywords: fixedpoint, hilbertspace, monotonemapping, resolventoperators

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11513 A Sliding Mesh Technique and Compressibility Correction Effects of Two-Equation Turbulence Models for a Pintle-Perturbed Flow Analysis

Authors: J. Y. Heo, H. G. Sung

Abstract:

Numerical simulations have been performed for assessment of compressibility correction of two-equation turbulence models suitable for large scale separation flows perturbed by pintle strokes. In order to take into account pintle movement, a sliding mesh method was applied. The chamber pressure, mass flow rate, and thrust have been analyzed, and the response lag and sensitivity at the chamber and nozzle were estimated for a movable pintle. The nozzle performance for pintle reciprocating as its insertion and extraction processes, were analyzed to better understand the dynamic performance of the pintle nozzle.

Keywords: pintle, sliding mesh, turbulent model, compressibility correction

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11512 Broccoli Sprouts Powder Could Improve Metabolic and Liver Disorder-Induced by High-Fructose Corn Syrup

Authors: Zahra Bahadoran, Parvin Mirmiran, Hanieh-Sadat Ejtahed, Maryam Tohidi, Fereidoun Azizi

Abstract:

Background and Aim: Broccoli sprouts, rich source of bioactive compounds specially sulforaphane (SFN), have unique functional properties. This study was conducted to investigate the possible treatment effects of high-SFN broccoli sprouts powder on metabolic and liver disorders in rats fed with high-fructose corn syrup. Methods: Thirty-two male wistar rats, pretreated with an eight-week high-fructose diet (water containing 30% fructose), were randomly allocated into three groups: Baseline control (BC), control (C) (normal diet), and BSP-diet (normal diet+5% BSP). The duration of the study was 6 weeks. Biochemical measurements, liver weight and triglyceride content were evaluated and histopathological examination of liver was performed. Results: After 6-weeks, the liver weight was significantly lower in BSP group compared to controls (13.4 g vs. 11.4 g, P<0.05). After 6 weeks, a significant decrease was observed in fasting serum glucose, total cholesterol and triglyceride levels in both experimental groups (P<0.05). Compared to controls, serum levels of HDL-C were significantly higher in BSP group. The liver TG content in BSP compared to control group was lower (14.6 vs. 16.4 mg/mg tissue). The hepatic levels of alanine aminotransferase, aspartate aminotransferase and γ-glutamyl transferase had not considerable changes in the groups after the intervention period but the level of alkaline phosphatase significantly decreased in BSP group (P<0.05). The histopathological examination of liver confirmed a decrease lobular and portal inflammation and ballooning in BSP group compared to control. Conclusion: High-SFN broccoli sprouts powder has beneficials effect on metabolic and liver changes-induced by high fructose corn syrup.

Keywords: broccoli sprouts, metabolic disorders, fatty liver, food science

Procedia PDF Downloads 410