Search results for: variable step size

Authors: Vladyslav Povoroznyuk, Oksana Ivanyk, Nataliia Dzerovych

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In the diagnostics of osteoporosis, the gold standard is considered to be bone mineral density; however, X-ray densitometry is not an accurate indicator of osteoporotic fracture risk under all circumstances. In this regard, the search for new methods that could determine the indicators not only of the mineral density, but of the bone tissue quality, is a logical step for diagnostic optimization. One of these methods is the evaluation of trabecular bone quality. The aim of this study was to examine the quality and mineral density of spine bone tissue, femoral neck, and body composition of women depending on the duration of the postmenopausal period, to determine the correlation of body fat with indicators of bone mineral density and quality. The study examined 179 women in premenopausal and postmenopausal periods. The patients were divided into the following groups: Women in the premenopausal period and women in the postmenopausal period at various stages (early, middle, late postmenopause). A general examination and study of the above parameters were conducted with General Electric X-ray densitometer. The results show that bone quality and mineral density probably deteriorate with advancing of postmenopausal period. Total fat and lean mass ratio is not likely to change with age. In the middle and late postmenopausal periods, the bone tissue mineral density of the spine and femoral neck increases along with total fat mass.

Keywords: osteoporosis, bone tissue mineral density, bone quality, fat mass, lean mass, postmenopausal osteoporosis

Procedia PDF Downloads 330

Authors: Anas Al-Ali, Mohammed Suleiman, Ayman Hussein

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Sulfur is an important element has many practical applications in present as nanoparticles. Nanosize sulfur particles also have many important applications like in pharmaceuticals, medicine, syn-thesis of nano-composites for lithium batteries, modification of carbon nano tubes. Different methods were used for nano-sized particle synthesis; among those, chemical precipitation, electrochemical method, micro emulsion technique, composing of oil, surfactant, co-surfactant, aqueous phases with the specific compositions and ultrasonic treatment of sulfur-cystine solution. In this work Sulfur nanoparticles (S NPs) were prepared by a quick precipitation method with and without using a surfactant to stabilize the formed S NPs. The synthesized S NPs were characterized by XRD, SEM and TEM in order to confirm their sizes and structures.Application of nanotechnology is suggested for diag-nosis and treatment of cancer. The anticancer activity of the prepared S NPs has been tested on various types of cancer cell clones including leukemia, kidney and colon cancers.

Keywords: sulfur nanoparticles (S-NPs), TEM, SEM, XRD

Procedia PDF Downloads 641

Authors: Weitao Zhou, Qing Wang, Jianxin He, Shizhong Cui

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Mesoporous Tussah silk fibroin (TSF) spheres were fabricated via the self-assembly of TSF molecules in aqueous solutions. The results showed that TSF particles were approximately three-dimensional spheres with the diameter ranging from 500nm to 6μm without adherence. More importantly, the surface morphology is mesoporous structure with nano-pores of 20nm - 200nm in size. Fourier transform infrared (FT-IR) and X-ray diffraction (XRD) studies demonstrated that mesoporous TSF spheres mainly contained beta-sheet conformation (44.1 %) as well as slight amounts of random coil (13.2 %). Drug release test was performed with 5-fluorouracil (5-Fu) as a model drug and the result indicated the mesoporous TSF microspheres had a good capacity of sustained drug release. It is expected that these stable and high-crystallinity mesoporous TSF sphere produced without organic solvents, which have significantly improved drug release properties, is a very promising material for controlled gene medicines delivery.

Keywords: Tussah silk fibroin, porous materials, microsphere, drug release

Procedia PDF Downloads 453

Authors: Preecha Phongpeng

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The objectives of this research are to assess the prevalence of travel businesses websites in Thailand, investigate and evaluate the quality of travel business websites in Thailand. The sample size includes 323 websites from the population of 1,458 websites. The study covers 4 types of travel business websites including: 78 general travel agents, 30 online reservation travel agents, 205 hotels, 7 airlines, and 3 car-rental companies with nation-wide operation. The findings indicated that e-tourism in Thailand is at its growth stage, with only 13% of travel businesses having websites, 28% of them providing e-mail and the quality of travel business websites in Thailand was at the average level. Seven common problems were found in websites: lack of travel essential information, insufficient transportation information, lack of navigation tools, lack of link pages to other organizations, lack of safety features, unclear online booking functions, and lack of special features also as well.

Keywords: traveling business, website evaluation, e-commerce, e-tourism

Procedia PDF Downloads 296

Authors: Teng Li, Kamran Mohseni

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This paper presents an inviscid regularization technique for the incompressible two-phase flow simulations. This technique is known as observable method due to the understanding of observability that any feature smaller than the actual resolution (physical or numerical), i.e., the size of wire in hotwire anemometry or the grid size in numerical simulations, is not able to be captured or observed. Differ from most regularization techniques that applies on the numerical discretization, the observable method is employed at PDE level during the derivation of equations. Difficulties in the simulation and analysis of realistic fluid flow often result from discontinuities (or near-discontinuities) in the calculated fluid properties or state. Accurately capturing these discontinuities is especially crucial when simulating flows involving shocks, turbulence or sharp interfaces. Over the past several years, the properties of this new regularization technique have been investigated that show the capability of simultaneously regularizing shocks and turbulence. The observable method has been performed on the direct numerical simulations of shocks and turbulence where the discontinuities are successfully regularized and flow features are well captured. In the current paper, the observable method will be extended to two-phase interfacial flows. Multiphase flows share the similar features with shocks and turbulence that is the nonlinear irregularity caused by the nonlinear terms in the governing equations, namely, Euler equations. In the direct numerical simulation of two-phase flows, the interfaces are usually treated as the smooth transition of the properties from one fluid phase to the other. However, in high Reynolds number or low viscosity flows, the nonlinear terms will generate smaller scales which will sharpen the interface, causing discontinuities. Many numerical methods for two-phase flows fail at high Reynolds number case while some others depend on the numerical diffusion from spatial discretization. The observable method regularizes this nonlinear mechanism by filtering the convective terms and this process is inviscid. The filtering effect is controlled by an observable scale which is usually about a grid length. Single rising bubble and Rayleigh-Taylor instability are studied, in particular, to examine the performance of the observable method. A pseudo-spectral method is used for spatial discretization which will not introduce numerical diffusion, and a Total Variation Diminishing (TVD) Runge Kutta method is applied for time integration. The observable incompressible Euler equations are solved for these two problems. In rising bubble problem, the terminal velocity and shape of the bubble are particularly examined and compared with experiments and other numerical results. In the Rayleigh-Taylor instability, the shape of the interface are studied for different observable scale and the spike and bubble velocities, as well as positions (under a proper observable scale), are compared with other simulation results. The results indicate that this regularization technique can potentially regularize the sharp interface in the two-phase flow simulations

Keywords: Euler equations, incompressible flow simulation, inviscid regularization technique, two-phase flow

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Authors: Maamar Latroch, Mohamed Bourahla

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Forward topology used in switch mode power supply (SMPS) is one of the most famous configuration feeding DC systems such as telecommunication systems and other specific applications where the galvanic isolation is required. This configuration benefits of the high frequency feature of the transformer to provide a small size and light weight of the over all system. However, the stresses existing on the power switch during an ON/OFF commutation limit the transmitted power to the DC load. This paper investigates the main causes of the stresses in voltage existing during a commutation cycle and suggest a low cost solution that eliminates the overvoltage. As a result, this configuration will yield the possibility of the use of this configuration in higher power applications. Simulation results will show the efficiency of the presented method.

Keywords: switch mode power supply, forward topology, resonance topology, high frequency commutation

Procedia PDF Downloads 428

Authors: Rouhallah Bagheri, Morteza Mahmoudi, Hadi Moheb-Alizadeh

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This paper aims at developing a multi-objective model for supplier selection and order allocation problem in stochastic environment, where purchasing cost, percentage of delivered items with delay and percentage of rejected items provided by each supplier are supposed to be stochastic parameters following any arbitrary probability distribution. In this regard, dependent chance programming is used which maximizes probability of the event that total purchasing cost, total delivered items with delay and total rejected items are less than or equal to pre-determined values given by decision maker. The abovementioned stochastic multi-objective programming problem is then transformed into a stochastic single objective programming problem using minimum deviation method. In the next step, the further problem is solved applying a genetic algorithm, which performs a simulation process in order to calculate the stochastic objective function as its fitness function. Finally, the impact of stochastic parameters on the given solution is examined via a sensitivity analysis exploiting coefficient of variation. The results show that whatever stochastic parameters have greater coefficients of variation, the value of the objective function in the stochastic single objective programming problem is deteriorated.

Keywords: supplier selection, order allocation, dependent chance programming, genetic algorithm

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Authors: Muhammad Izzam Bin Mohd Khazar, Ruqayyah Binti Mohamad Ali, Nurul Atiqah Binti Yusri

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Value-based intermediation (VBI) has been introduced by Bank Negara Malaysia (BNM) as the next strategic direction and growth driver for Islamic banking institutions. The aim of VBI is to deliver the intended outcome of Shariah through practices, conducts, and offerings that generate positive and sustainable impact to the economy, community and environment which is aligned to Maqasid Shariah in preserving the common interest of society by preventing harm and maximizing benefit. Hence, upon its implementation, VBI will experiment the current Shariah compliance treatment and revolutionise new policies and systems that can meritoriously entrench and convey the objectives of Shariah. However, discussion revolving VBI in the light of Maqasid analysis is still scarce hence further research needs to be undertaken. The idea of implementation of VBI vision into quantifiable Maqasid Shariah measurement is yet to be explored due to the nature of Maqasid that is variable. The contemporary scholars also have different views on the implementation of VBI. This paper aims to discuss on the importance of Maqasid Shariah in the current Islamic finance transactions by providing Shariah index measurement in the application of VBI. This study also intends to explore basic Shariah guidelines and parameters based on the objectives of Shariah; preservation of the five pillars (religion, life, progeny, intellect and wealth) with further elaboration on preservation of wealth under five headings: rawaj (circulation and marketability); wuduh (transparency); hifz (preservation); thabat (durability and tranquillity); and ‘adl (equity and justice). In alignment with these headings, Islamic finance can be innovated for VBI implementation, particularly in Maybank Islamic being a significant leader in the IFI market.

Keywords: Islamic Financial Institutions, Maqasid Index, Maqasid Shariah, sustainability, value-based intermediation

Procedia PDF Downloads 157

Authors: Anas Al-Ali, Mohammed Suleiman, Ayman Hussein

Abstract:

Sulfur is an important element has many practical applications in present as nanoparticles. Nanosize sulfur particles also have many important applications like in pharmaceuticals, medicine, synthesis of nanocomposites for lithium batteries, modification of carbon nanotubes. Different methods were used for nano-sized particle synthesis; among those, chemical precipitation, electrochemical method, micro-emulsion technique, composing of oil, surfactant, co-surfactant, aqueous phases with the specific compositions and ultrasonic treatment of sulfur-cystine solution. In this work, sulfur nanoparticles (S NPs) were prepared by a quick precipitation method with and without using a surfactant to stabilize the formed S NPs. The synthesized S NPs were characterized by XRD, SEM, and TEM in order to confirm their sizes and structures. Application of nanotechnology is suggested for diagnosis and treatment of cancer. The anticancer activity of the prepared S NPs has been tested on various types of cancer cell clones including leukemia, kidney and colon cancers.

Keywords: sulfur nanoparticles (S-NPs), TEM, SEM, anti cancer activity, XRD

Procedia PDF Downloads 507

Authors: Banca Patricia Pena Revuelta, Ramiro Gonzalez Avalos, Juan Leonardo Rocha Valdez, Jose Gonzalez Avalos, Karla Rodriguez Hernandez

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Probiotics are a promising alternative to improve productivity and animals' health. In addition, they can be part of the composition of different types of products, including foods (functional foods), medicines, and dietary supplements. The objective of the present work was to evaluate the effect of the feeding of Holstein calves supplemented with bacillus subtilis PB6 in morbidity and mortality. 60 newborn animals were used, randomly included in 1 of 3 treatments. The treatments were as follows: T1 = control, T2 = 10 g / calf / day. The first takes within 20 min after birth, T3 = 10 g / calf/day. The first takes between 12 and 24 h after birth. In all the treatments, 432 L of pasteurized whole milk divided into two doses/day 07:00 and 15:00, respectively, were given for 60 days. The addition of bacillus subtilis PB6 was carried out in the milk tub at the time of feeding them. The first colostrum intake (2 L • intake) was given within 2 h after birth, after which they were given a second 6 h after the first one. The diseases registered to monitor the morbidity and mortality of the calves were: diarrhea and pneumonia. The registry was carried out from birth to 60 days of life. The parameter evaluated was food consumption. The variable statistical analysis was performed using analysis of variance, and comparison of means was performed using the Tukey test. The value of P < 0.05 was used to consider the statistical difference. The results of the present study in relation to the consumption of food show no statistical difference P < 0.05 between treatments (14,762, 11,698, and 12,403 kg of food average, respectively). Calves group to which they were not provided Bacillus subtilis PB6 obtained higher feed intake. The addition of Bacillus subtilis PB6 in feeding calves does not increase feed intake.

Keywords: feeding, development, milk, probiotic

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Authors: Aydin Teymourifar, Gurkan Ozturk

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In this paper, a distributed hybrid algorithm is proposed for solving the job shop scheduling problem. The suggested method executes different artificial neural networks, heuristics and meta-heuristics simultaneously on more than one machine. The neural networks are used to control the constraints of the problem while the meta-heuristics search the global space and the heuristics are used to prevent the premature convergence. To attain an efficient distributed intelligent method for solving big and distributed job shop scheduling problems, Apache Spark and Hadoop frameworks are used. In the algorithm implementation and design steps, new approaches are applied. Comparison between the proposed algorithm and other efficient algorithms from the literature shows its efficiency, which is able to solve large size problems in short time.

Keywords: distributed algorithms, Apache Spark, Hadoop, job shop scheduling, neural network

Procedia PDF Downloads 377

Authors: C. Elavarasi, T. Shanmuganantham

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A coplanar waveguide (CPW) feed is presented, and comprising a split ring resonator (SRR) loaded fractal with water lily shape is used for multi band applications. The impedance matching of the antenna is determined by the number of Koch curve fractal unit cells. The antenna is designed on a FR4 substrate with a permittivity of ε_{r =} 4.4 and size of 14 x 16 x 1.6 mm³ to generate multi resonant mode at 3.8 GHz covering S band, 8.68 GHz at X band, 13.96 GHz at Ku band, and 19.74 GHz at K band with reflection coefficient better than -10 dB. Simulation results show that the antenna exhibits the desired voltage standing wave ratio (VSWR) level and radiation patterns across the wide frequency range. The fundamental parameters of the antenna such as return loss, VSWR, good radiation pattern with reasonable gain across the operating bands are obtained.

Keywords: fractal, metamaterial, split ring resonator, waterlily shape

Procedia PDF Downloads 267

Authors: Joshefina Bengoechea Fernandez, Alex Bell

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In its 2021 guidance for policy makers, the UNESCO has proposed 4 areas where AI can be applied in educational settings: These are: 1) Education management and delivery; 2) Learning and assessment; 3) Empowering teachers and facilitating teaching, and 4) Providing lifelong learning possibilities (UNESCO, 2021). Like with wblockchain technologies, AI will automate the management of educational institutions. These include, but are not limited to admissions, timetables, attendance, and homework monitoring. Furthermore, AI will be used to select relevant learning content across learning platforms for each student, based on his or her personalized needs. A problem educators face is the “one-size-fits-all” approach that does not work with a diverse student population. The purpose of this paper is to illustrate if the implementation of Technology is the solution to the Problems faced in Higher Education. The paper builds upon a constructivist approach, combining a literature review and research on key publications and academic reports.

Keywords: artificial intelligence, learning platforms, students personalised needs, life- long learning, privacy, ethics

Procedia PDF Downloads 92

Authors: J. G. Batista, L. J. de Bessa Neto, M. A. F. B. Lima, J. R. Leite, J. I. de Andrade Nunes

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The robot manipulator is an equipment that stands out for two reasons: Firstly because of its characteristics of movement and reprogramming, resembling the arm; secondly, by adding several areas of knowledge of science and engineering. The present work shows the development of the prototype of a robotic manipulator driven by a Programmable Logic Controller (PLC), having two degrees of freedom, which allows the movement and displacement of mechanical parts, tools, and objects in general of small size, through an electronic system. The aim is to study direct and inverse kinematics of the robotic manipulator to describe the translation and rotation between two adjacent links of the robot through the Denavit-Hartenberg parameters. Currently, due to the many resources that microcomputer systems offer us, robotics is going through a period of continuous growth that will allow, in a short time, the development of intelligent robots with the capacity to perform operations that require flexibility, speed and precision.

Keywords: Denavit-Hartenberg, direct and inverse kinematics, microcontrollers, robotic manipulator

Procedia PDF Downloads 338

Authors: Ujjal Chattaraj, Pbharat Saikumar, Thinley Dorji

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Earth is going to be a planet where no further life can sustain if people continue to pollute the environment. We need energy and fuels everyday for heating and lighting purposes in our life. It’s high time we know this problem and take measures at-least to reduce pollution and take alternative measures for everyday livelihood. Biogas is one of them. It is very essential to define and control the parameters for optimization of biogas production. Biogas plants can be made of different size, but it is very vital to make a biogas which will be cost effective, with greater efficiency (more production) and biogas plants that will sustain for a longer period of time for usage. In this research, experiments were carried out only on cow dung and Chicken manure depending on the substrates people out there (Bhutan) used. The experiment was done within 25 days and was tested for different temperatures and found out which produce more amount. Moreover, it was also statistically tested for their dependency and non-dependency which gave clear idea more on their production.

Keywords: digester, mesophilic temperature, organic manure, statistical analysis, thermophilic temperature, t-test

Procedia PDF Downloads 191

Authors: Svetlana Ignatjeva, Jelena Slesareva

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The aim of the study is development and adaptation of the method to analyze and quantify the indicators characterizing the relationship between a company and its employees. Diagnostics of such indicators is one of the most complex and actual issues in psychology of labour. The offered method is based on the questionnaire; its indicators reflect cognitive, affective and connotative components of socio-psychological attitude of employees to be as efficient as possible in their professional activities. This approach allows measure not only the selected factors but also such parameters as cognitive and behavioural dissonances. Adaptation of the questionnaire includes factor structure analysis and suitability analysis of phenomena indicators measured in terms of internal consistency of individual factors. Structural validity of the questionnaire was tested by exploratory factor analysis. Extraction Method: Principal Component Analysis. Rotation Method: Varimax with Kaiser Normalization. Factor analysis allows reduce dimension of the phenomena moving from the indicators to aggregative indexes and latent variables. Aggregative indexes are obtained as the sum of relevant indicators followed by standardization. The coefficient Cronbach's Alpha was used to assess the reliability-consistency of the questionnaire items. The two-step cluster analysis in the space of allocated factors allows classify employees according to their attitude to work in the company. The results of psychometric testing indicate possibility of using the developed technique for the analysis of employees’ attitude towards their work in companies and development of recommendations on their optimization.

Keywords: involved in the organization, loyalty, organizations, method

Procedia PDF Downloads 349

Authors: Angelis P. Barlampas

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Learning Objectives: The purpose of this study is to inform briefly the reader about the applications of AI in chest radiology. Background: Currently, there are 190 FDA-approved radiology AI applications, with 42 (22%) pertaining specifically to thoracic radiology. Imaging findings OR Procedure details Aids of AI in chest radiology1: Detects and segments pulmonary nodules. Subtracts bone to provide an unobstructed view of the underlying lung parenchyma and provides further information on nodule characteristics, such as nodule location, nodule two-dimensional size or three dimensional (3D) volume, change in nodule size over time, attenuation data (i.e., mean, minimum, and/or maximum Hounsfield units [HU]), morphological assessments, or combinations of the above. Reclassifies indeterminate pulmonary nodules into low or high risk with higher accuracy than conventional risk models. Detects pleural effusion . Differentiates tension pneumothorax from nontension pneumothorax. Detects cardiomegaly, calcification, consolidation, mediastinal widening, atelectasis, fibrosis and pneumoperitoneum. Localises automatically vertebrae segments, labels ribs and detects rib fractures. Measures the distance from the tube tip to the carina and localizes both endotracheal tubes and central vascular lines. Detects consolidation and progression of parenchymal diseases such as pulmonary fibrosis or chronic obstructive pulmonary disease (COPD).Can evaluate lobar volumes. Identifies and labels pulmonary bronchi and vasculature and quantifies air-trapping. Offers emphysema evaluation. Provides functional respiratory imaging, whereby high-resolution CT images are post-processed to quantify airflow by lung region and may be used to quantify key biomarkers such as airway resistance, air-trapping, ventilation mapping, lung and lobar volume, and blood vessel and airway volume. Assesses the lung parenchyma by way of density evaluation. Provides percentages of tissues within defined attenuation (HU) ranges besides furnishing automated lung segmentation and lung volume information. Improves image quality for noisy images with built-in denoising function. Detects emphysema, a common condition seen in patients with history of smoking and hyperdense or opacified regions, thereby aiding in the diagnosis of certain pathologies, such as COVID-19 pneumonia. It aids in cardiac segmentation and calcium detection, aorta segmentation and diameter measurements, and vertebral body segmentation and density measurements. Conclusion: The future is yet to come, but AI already is a helpful tool for the daily practice in radiology. It is assumed, that the continuing progression of the computerized systems and the improvements in software algorithms , will redder AI into the second hand of the radiologist.

Keywords: artificial intelligence, chest imaging, nodule detection, automated diagnoses

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Authors: Elham Taghizade Sigarodi, Ani Mirzakhanian

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Journalism atmosphere in present era is highly competitive so that what matters the most is “the speed of news broadcasting”. The first newspaper that lets out the news is therefore of higher validity. The value of the news is in fact in its truthfulness. Expressing the facts and reality is an accepted norm in professional media arena and it is as well considered the acceptable and trustworthy language for journalism. However, different conditions generate self-censorship. The present study seeks to explore the relationship between self-censorship and satisfaction of Iran newspaper’s readers. Thus, the statistical population including journalists of Iran newspaper for Tehran’s readers was estimated 384 persons based on Morgan table. Through cluster sampling, 50 journalists were selected so that totally the sample size was 434 persons and questionnaire was applied for data analysis and based on Alpha Chronbache, it was supported. Through Pierson correlation, the main and all subsidiary hypotheses were supported except the forth one.

Keywords: newspaper, satisfaction of audiences, self-censorship, journalists

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Authors: Dina Kon Mushid, Kabutakapua Kakanda, Dibu Dave Mbako

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The failure of material usually involves elastoplastic deformation and fracturing. Continuum mechanics can effectively deal with plastic deformation by using a yield function and the flow rule. At the same time, it has some limitations in dealing with the fracture problem since it is a theory based on the continuous field hypothesis. The lattice model can simulate the fracture problem very well, but it is inadequate for dealing with plastic deformation. Based on the discretized virtual internal bond model (DVIB), this paper proposes a lattice model that can account for plasticity. DVIB is a lattice method that considers material to comprise bond cells. Each bond cell may have any geometry with a finite number of bonds. The two-body or multi-body potential can characterize the strain energy of a bond cell. The two-body potential leads to the fixed Poisson ratio, while the multi-body potential can overcome the limitation of the fixed Poisson ratio. In the present paper, the modified Stillinger-Weber (SW), a multi-body potential, is employed to characterize the bond cell energy. The SW potential is composed of two parts. One part is the two-body potential that describes the interatomic interactions between particles. Another is the three-body potential that represents the bond angle interactions between particles. Because the SW interaction can represent the bond stretch and bond angle contribution, the SW potential-based DVIB (SW-DVIB) can represent the various Poisson ratios. To embed the plasticity in the SW-DVIB, the plasticity is considered in the two-body part of the SW potential. It is done by reducing the bond stiffness to a lower level once the bond reaches the yielding point. While before the bond reaches the yielding point, the bond is elastic. When the bond deformation exceeds the yielding point, the bond stiffness is softened to a lower value. When unloaded, irreversible deformation occurs. With the bond length increasing to a critical value, termed the failure bond length, the bond fails. The critical failure bond length is related to the cell size and the macro fracture energy. By this means, the fracture energy is conserved so that the cell size sensitivity problem is relieved to a great extent. In addition, the plasticity and the fracture are also unified at the bond level. To make the DVIB able to simulate different Poisson ratios, the three-body part of the SW potential is kept elasto-brittle. The bond angle can bear the moment before the bond angle increment is smaller than a critical value. By this method, the SW-DVIB can simulate the plastic deformation and the fracturing process of material with various Poisson ratios. The elastoplastic SW-DVIB is used to simulate the plastic deformation of a material, the plastic fracturing process, and the tunnel plastic deformation. It has been shown that the current SW-DVIB method is straightforward in simulating both elastoplastic deformation and plastic fracture.

Keywords: lattice model, discretized virtual internal bond, elastoplastic deformation, fracture, modified stillinger-weber potential

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Authors: Fereshteh Chekin, Sepideh Sadeghi

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Nickel nanoparticles have attracted much attention because of applications in catalysis, medical diagnostics and magnetic applications. In this work, we reported a simple and low-cost procedure to synthesize nickel oxide nanoparticles (NiO-NPs) by using sodium dodecyl sulphate (SDS) and gelatin as stabilizer. The synthesized NiO-NPs were characterized by a variety of means such as transmission electron microscope (TEM), powder X-ray diffraction (XRD), scanning electron microscope (SEM) and UV-vis spectroscopy. The results show that the NiO nanoparticles with high crystalline can be obtained using this simple method. The grain size measured by TEM was 16 in presence of SDS, which agrees well with the XRD data. SDS plays an important role in the formation of the NiO nanoparticles. Moreover, the NiO nanoparticles have been used as a solid phase catalyst for the decomposition of hydrazine hydrate at room temperatures. The decomposition process has been monitored by UV–vis analysis. The present study showed that nanoparticles are not poisoned after their repeated use in decomposition of hydrazine.

Keywords: nickel oxide nanoparticles, sodium dodecyl sulphate, synthesis, stabilizer

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Authors: Dandi Bachtiar, Mohammed Ausama Abbas, Januar Parlaungan Siregar, Mohd Ruzaimi Bin Mat Rejab

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Short sugar palm fibre and thermoplastic polyurethane were combined to produce new composites by using the extrude method. Two techniques used to prepare a new composite material, firstly, extrusion of the base material with short fibre, secondly hot pressing them. The size of sugar palm fibre was fixed at 250µm. Different weight percent (10 wt%, 20 wt% and 30 wt%) were used in order to optimise preparation process. The optimization of process depended on the characterization mechanical properties such as impact, tensile, and flexural of the new (TPU/SPF) composite material. The results proved that best tensile and impact properties of weight additive fibre applied 10 wt%. There was an increasing trend recorded of flexural properties during increased the fibre loading. Meanwhile, the maximum tensile strength was 14.0 MPa at 10 wt% of the fibre. Moreover, there was no significant effect for additions more than 30 wt% of the fibre.

Keywords: composites, natural fibre, polyurethane, sugar palm

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Authors: Ayush Shrivastava, Arpit Chaudhary, Devang Kulshreshtha, Vibhav Prakash Singh, Rajeev Srivastava

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Early diagnosis of breast cancer can improve the survival rate by detecting cancer at an early stage. Breast region segmentation is an essential step in the analysis of digital mammograms. Accurate image segmentation leads to better detection of cancer. It aims at separating out Region of Interest (ROI) from rest of the image. The procedure begins with removal of labels, annotations and tags from the mammographic image using morphological opening method. Pectoral Muscle Sliding Window Algorithm (PMSWA) is used for removal of pectoral muscle from mammograms which is necessary as the intensity values of pectoral muscles are similar to that of ROI which makes it difficult to separate out. After removing the pectoral muscle, Dispersed Region Growing Algorithm (DRGA) is used for segmentation of mammogram which disperses seeds in different regions instead of a single bright region. To demonstrate the validity of our segmentation method, 322 mammographic images from Mammographic Image Analysis Society (MIAS) database are used. The dataset contains medio-lateral oblique (MLO) view of mammograms. Experimental results on MIAS dataset show the effectiveness of our proposed method.

Keywords: CAD, dispersed region growing algorithm (DRGA), image segmentation, mammography, pectoral muscle sliding window algorithm (PMSWA)

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Authors: Htet Khaing Lin

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This study explores the relationship between a diverse set of variables, encompassing both environmental and socio-economic factors, and poverty levels in the Philippines for the years 2012, 2015, and 2018. Employing Ordinary Least Squares (OLS), Spatial Lag Models (SLM), and Spatial Error Models (SEM), this study delves into the dynamics of key indicators, including daytime and nighttime land surface temperature, cropland surface, urban land surface, rainfall, population size, normalized difference water, vegetation, and drought indices. The findings reveal consistent patterns and unexpected correlations, highlighting the need for nuanced policies that address the multifaceted challenges arising from the interplay of environmental and socio-economic factors.

Keywords: poverty analysis, OLS, spatial lag models, spatial error models, Philippines, google earth engine, satellite data, environmental dynamics, socio-economic factors

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Authors: Yogish Huchaiah, Chandrashekara Krishnappa

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This study considers the optimization and validation of experimental results using Multi-Functional Criteria Technique (MFCT). MFCT is concerned with structuring and solving decision and planning problems involving multiple variables. Production of biodiesel from Composite Oil Methyl Esters (COME) of Jatropha and Pongamia oils, mixed in various proportions and Biodiesel thus obtained from two step transesterification process were tested for various Physico-Chemical properties and it has been ascertained that they were within limits proposed by ASTME. They were blended with Petrodiesel in various proportions. These Methyl Esters were blended with Petrodiesel in various proportions and coded. These blends were used as fuels in a computerized CI DI engine to investigate Performance and Emission characteristics. From the analysis of results, it was found that 180MEM4B20 blend had the maximum Performance and minimum Emissions. To validate the experimental results, MFCT was used. Characteristics such as Fuel Consumption (FC), Brake Power (BP), Brake Specific Fuel Consumption (BSFC), Brake Thermal Efficiency (BTE), Carbon dioxide (CO2), Carbon Monoxide (CO), Hydro Carbon (HC) and Nitrogen oxide (NOx) were considered as dependent variables. It was found from the application of this method that the optimized combination of Injection Pressure (IP), Mix and Blend is 178MEM4.2B24. Overall corresponding variation between optimization and experimental results was found to be 7.45%.

Keywords: COME, IP, MFCT, optimization, PI, PN, PV

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Authors: Xuechun Kan, Dongdong Li, Fan Li, Peidang Liu

Abstract:

Triple-negative breast cancer (TNBC) is the most malignant subtype of breast cancer with a poor prognosis, and radiotherapy is one of the main treatment methods. However, due to the obvious resistance of tumor cells to radiotherapy, high dose of ionizing radiation is required during radiotherapy, which causes serious damage to normal tissues near the tumor. Therefore, how to improve radiotherapy resistance and enhance the specific killing of tumor cells by radiation is a hot issue that needs to be solved in clinic. Recent studies have shown that silver-based nanoparticles have strong radiosensitization, and silver nanoclusters (AgNCs) also provide a broad prospect for tumor targeted radiosensitization therapy due to their ultra-small size, low toxicity or non-toxicity, self-fluorescence and strong photostability. Aptamer 5TR1 is a 25-base oligonucleotide aptamer that can specifically bind to mucin-1 highly expressed on the membrane surface of TNBC 4T1 cells, and can be used as a highly efficient tumor targeting molecule. In this study, AgNCs were synthesized by DNA template based on 5TR1 aptamer (NC-T5-5TR1), and its role as a targeted radiosensitizer in TNBC radiotherapy was investigated. The optimal DNA template was first screened by fluorescence emission spectroscopy, and NC-T5-5TR1 was prepared. NC-T5-5TR1 was characterized by transmission electron microscopy, ultraviolet-visible spectroscopy and dynamic light scattering. The inhibitory effect of NC-T5-5TR1 on cell activity was evaluated using the MTT method. Laser confocal microscopy was employed to observe NC-T5-5TR1 targeting 4T1 cells and verify its self-fluorescence characteristics. The uptake of NC-T5-5TR1 by 4T1 cells was observed by dark-field imaging, and the uptake peak was evaluated by inductively coupled plasma mass spectrometry. The radiation sensitization effect of NC-T5-5TR1 was evaluated through cell cloning and in vivo anti-tumor experiments. Annexin V-FITC/PI double staining flow cytometry was utilized to detect the impact of nanomaterials combined with radiotherapy on apoptosis. The results demonstrated that the particle size of NC-T5-5TR1 is about 2 nm, and the UV-visible absorption spectrum detection verifies the successful construction of NC-T5-5TR1, and it shows good dispersion. NC-T5-5TR1 significantly inhibited the activity of 4T1 cells and effectively targeted and fluoresced within 4T1 cells. The uptake of NC-T5-5TR1 reached its peak at 3 h in the tumor area. Compared with AgNCs without aptamer modification, NC-T5-5TR1 exhibited superior radiation sensitization, and combined radiotherapy significantly inhibited the activity of 4T1 cells and tumor growth in 4T1-bearing mice. The apoptosis level of NC-T5-5TR1 combined with radiation was significantly increased. These findings provide important theoretical and experimental support for NC-T5-5TR1 as a radiation sensitizer for TNBC.

Keywords: 5TR1 aptamer, silver nanoclusters, radio sensitization, triple-negative breast cancer

Procedia PDF Downloads 41

Authors: Rafael Zhindon Almeida

Abstract:

Surface water quality is an important concern for the evaluation and prediction of water quality conditions. The objective of this study is to develop a statistical model that can accurately predict the water quality of the El Macho estuary in the city of Machala, El Oro province. The methodology employed in this study is of a basic type that involves a thorough search for theoretical foundations to improve the understanding of statistical modeling for water quality analysis. The research design is correlational, using a multivariate statistical model involving multiple linear regression and principal component analysis. The results indicate that water quality parameters such as fecal coliforms, biochemical oxygen demand, chemical oxygen demand, iron and dissolved oxygen exceed the allowable limits. The water of the El Macho estuary is determined to be below the required water quality criteria. The multiple linear regression model, based on chemical oxygen demand and total dissolved solids, explains 99.9% of the variance of the dependent variable. In addition, principal component analysis shows that the model has an explanatory power of 86.242%. The study successfully developed a statistical model to evaluate the water quality of the El Macho estuary. The estuary did not meet the water quality criteria, with several parameters exceeding the allowable limits. The multiple linear regression model and principal component analysis provide valuable information on the relationship between the various water quality parameters. The findings of the study emphasize the need for immediate action to improve the water quality of the El Macho estuary to ensure the preservation and protection of this valuable natural resource.

Keywords: statistical modeling, water quality, multiple linear regression, principal components, statistical models

Procedia PDF Downloads 81

Authors: Mei Hong, Wei Liu, Xuemin Dai, Yanxiong Pan, Xiangling Ji

Abstract:

Polyamic acid (PAA) is the precursor of polyimide (PI) prepared by a two-step method, its molecular weight and molecular weight distribution not only play an important role during the preparation and processing, but also influence the final performance of PI. However, precise characterization on molecular weight of PAA is still a challenge because of the existence of very complicated interactions in the solution system, including the electrostatic interaction, hydrogen bond interaction, dipole-dipole interaction, etc. Thus, it is necessary to establisha suitable strategy which can completely suppress these complex effects and get reasonable data on molecular weight. Herein, the gel permeation chromatography (GPC) coupled with differential refractive index (RI) and multi-angle laser light scattering (MALLS) detectors were applied to measure the molecular weight of (6FDA-DMB) PAA using different mobile phases, LiBr/DMF, LiBr/H3PO4/THF/DMF, LiBr/HAc/THF/DMF, and LiBr/HAc/DMF, respectively. It was found that combination of LiBr with HAc can shield the above-mentioned complex interactions and is more conducive to the separation of PAA than only addition of LiBr in DMF. LiBr/HAc/DMF was employed for the first time as a mild mobile phase to effectively separate PAA and determine its molecular weight. After a series of conditional experiments, 0.02M LiBr/0.2M HAc/DMF was fixed as an optimized mobile phase to measure the relative and absolute molecular weights of (6FDA-DMB) PAA prepared, and the obtained Mw from GPC-MALLS and GPC-RI were 35,300 g/mol and 125,000 g/mol, respectively. Particularly, such a mobile phase is also applicable to other PAA samples with different structures, and the final results on molecular weight are also reproducible.

Keywords: Polyamic acids, Polyelectrolyte effects, Gel permeation chromatography, Mobile phase, Molecular weight

Procedia PDF Downloads 44

Authors: K. W. Nam, B. J. Kim, S. J. Lee

Abstract:

Along with the development of network infrastructures, such as high-speed Internet and mobile environment, the explosion of multimedia data is expanding the range of multimedia services beyond voice and data services. Amid this flow, research is actively being done on the creation, management, and transmission of metadata on digital content to provide different services to users. This paper proposes a system for the insertion, storage, and retrieval of metadata about digital content. The metadata server with Binary XML was implemented for efficient storage space and retrieval speeds, and the transport data size required for metadata retrieval was simplified. With the proposed system, the metadata could be inserted into the moving objects in the video, and the unnecessary overlap could be minimized by improving the storage structure of the metadata. The proposed system can assemble metadata into one relevant topic, even if it is expressed in different media or in different forms. It is expected that the proposed system will handle complex network types of data.

Keywords: video, multimedia, metadata, editing tool, XML

Procedia PDF Downloads 159

Authors: J. Castaño, S. Rodriguez, C. M. L. Franco

Abstract:

Starch isolated from non-edible A. hippocastanum seeds was characterized and used for preparing starch-based materials. The apparent amylose content of the isolated starch was 33.1%. The size of starch granules ranged from 0.7 to 35µm, and correlated with the shape of granules (spherical, oval and irregular). The chain length distribution profile of amylopectin showed two peaks, at polymerization degree (DP) of 12 and 41-43. Around 53% of branch unit chains had DP in the range of 11-20. A. hippocastanum starch displayed a typical C-type pattern and the maximum decomposition temperature was 317°C. Thermoplastic starch (TPS) prepared from A. hippocastanum with glycerol and processed by melt blending exhibited adequate mechanical and thermal properties. In contrast, plasticized TPS with glycerol:malic acid (1:1) showed lower thermal stability and a pasty and sticky behavior, indicating that malic acid accelerates degradation of starch during processing.

Keywords: Aesculus hippocastanum L., amylopectin structure, thermoplastic starch, non-edible source

Procedia PDF Downloads 362

Authors: Naod Mekonnen Anega

Abstract:

The very objective of this paper was to empirically identify technology tailored determinants to the adoption and adoption intensity (extent of use) of agricultural water management technologies in Meda Welabu Woreda, Oromia regional state, Ethiopia. Meda Welabu Woreda which is one of the administrative Woredas of the Oromia regional state was selected purposively as this Woreda is one of the Woredas in the region where small scale irrigation practices and the use of agricultural water management technologies can be found among smallholders. Using the existence water management practices (use of water management technologies) and land use pattern as a criterion Genale Mekchira Kebele is selected to undergo the study. A total of 200 smallholders were selected from the Kebele using the technique developed by Krejeie and Morgan. The study employed the Logit and Tobit models to estimate and identify the economic, social, geographical, household, institutional, psychological, technological factors that determine adoption and adoption intensity of water management technologies. The study revealed that while 55 of the sampled households are adopters of agricultural water management technology the rest 140 were non adopters of the technologies. Among the adopters included in the sample 97% are using river diversion technology (traditional) with traditional canal while the rest 7% percent are using pond with treadle pump technology. The Logit estimation reveled that while adoption of river diversion is positively and significantly affected by membership to local institutions, active labor force, income, access to credit and land ownership, adoption of treadle pump technology is positively and significantly affected by family size, education level, access to credit, extension contact, income, access to market, and slope. The Logit estimation also revealed that whereas, group action requirement, distance to farm, and size of active labor force negative and significantly influenced adoption of river diversion, age and perception has negatively and significantly influenced adoption decision of treadle pump technology. On the other hand, the Tobit estimation reveled that while adoption intensity (extent of use) of agricultural water management is positively and significantly affected by education, credit, and extension contact, access to credit, access to market and income. This study revealed that technology tailored study on adoption of Agricultural water management technologies (AWMTs) should be considered to indentify and scale up best agricultural water management practices. In fact, in countries like Ethiopia, where there is difference in social, economic, cultural, environmental and agro ecological conditions even within the same Kebele technology tailored study that fit the condition of each Kebele would help to identify and scale up best practices in agricultural water management.

Keywords: water management technology, adoption, adoption intensity, smallholders, technology tailored approach

Procedia PDF Downloads 439