Search results for: long short-term memory cell
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10104

Search results for: long short-term memory cell

5514 An Experimental Investigation into Fluid Forces on Road Vehicles in Unsteady Flows

Authors: M. Sumida, S. Morita

Abstract:

In this research, the effect of unsteady flows acting on road vehicles was experimentally investigated, using an advanced and recently introduced wind tunnel. The aims of this study were to extract the characteristics of fluid forces acting on road vehicles under unsteady wind conditions and obtain new information on drag forces in a practical on-road test. We applied pulsating wind as a representative example of the atmospheric fluctuations that vehicles encounter on the road. That is, we considered the case where the vehicles are moving at constant speed in the air, with large wind oscillations. The experimental tests were performed on the Ahmed-type test model, which is a simplified vehicle model. This model was chosen because of its simplicity and the data accumulated under steady wind conditions. The experiments were carried out with a time-averaged Reynolds number of Re = 4.16x10⁵ and a pulsation period of T = 1.5 s, with amplitude of η = 0.235. Unsteady fluid forces of drag and lift were obtained utilizing a multi-component load cell. It was observed that the unsteady aerodynamic forces differ significantly from those under steady wind conditions. They exhibit a phase shift and an enhanced response to the wind oscillations. Furthermore, their behavior depends on the slant angle of the rear shape of the model.

Keywords: Ahmed body, automotive aerodynamics, unsteady wind, wind tunnel test

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5513 Study the Effect of Lipoid Acid as a Protective Against Rheumatoid Arthritis Through Diminishing Pro-inflammatory Markers and Chemokine Expression

Authors: Khairy Mohamed Abdalla Zoheir

Abstract:

One of the most severe complications of Rheumatoid arthritis is delayed recovery. lipoic acid possesses antioxidant, hypoglycemic, and anti-inflammatory activity. In the present study, the effects of lipoic acid were investigated on the key mediators of Rheumatoid arthritis, namely, CD4+CD25+ T cell subsets, GITR expressing cells, CD4+CD25+Foxp3+ regulatory T (Treg) cells, T-helper-17 (Th17) cells and pro-inflammatory cytokines Interleukin-1β (IL-1β), Interleukin-6 (IL-6) and Tumor Necrosis Factor- α (TNF-α)] through flow-cytometry and qPCR analyses. Lipoic acid-treated mice showed a significant decrease in Rheumatoid arthritis, the frequency of GITR-expressing cells, and Th1 cytokines (IL-17A, TNF-αand Interferon- γ (IFN-γ) compared with positive and negative controlled mice. Lipoic acid treatment also downregulated the mRNA expression of the inflammatory mediators compared with the Rheumatoid arthritis mouse model and untreated mice. The number of Tregs was also found to be significantly upregulated in lipoic acid-treated mice. Our results were confirmed by the histopathological examination. This study showed the beneficial role of lipoic acid in promoting a well-balanced tool for the therapy of Rheumatoid arthritis.

Keywords: lipoic acid, inflammatory markers, rheumatoid arthritis, qPCR

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5512 Trauma-Informed Leadership: Educational Leadership Practices in a Global Pandemic

Authors: Kyna Elliott

Abstract:

The COVID-19 global pandemic has changed the shape, design, and delivery of education. As communities continue to fight the pandemic, research suggests the coronavirus is leaving an indelible mark on education which will last long after the pandemic has ended. Faculty and students bring more than their textbooks into the classroom. They bring their lived experiences into the classroom, and it is through these lived experiences that interactions and learning filter through. The COVID-19 pandemic has proved to be a traumatic experience for many. Leaders will need to have the tools and skills to mitigate trauma's impact on faculty and students. This presentation will explore research-based trauma-informed leadership practices, pedagogy, and mitigation strategies within secondary school environments.

Keywords: COVID-19, compassion fatigue, educational leadership, the science of trauma, trauma-informed leadership, trauma-informed pedagogy

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5511 Spectral Broadening in an InGaAsP Optical Waveguide with χ(3) Nonlinearity Including Two Photon Absorption

Authors: Keigo Matsuura, Isao Tomita

Abstract:

We have studied a method to widen the spectrum of optical pulses that pass through an InGaAsP waveguide for application to broadband optical communication. In particular, we have investigated the competitive effect between spectral broadening arising from nonlinear refraction (optical Kerr effect) and shrinking due to two photon absorption in the InGaAsP waveguide with chi^(3) nonlinearity. The shrunk spectrum recovers broadening by the enhancement effect of the nonlinear refractive index near the bandgap of InGaAsP with a bandgap wavelength of 1490 nm. The broadened spectral width at around 1525 nm (196.7 THz) becomes 10.7 times wider than that at around 1560 nm (192.3 THz) without the enhancement effect, where amplified optical pulses with a pulse width of 2 ps and a peak power of 10 W propagate through a 1-cm-long InGaAsP waveguide with a cross-section of 4 um^2.

Keywords: InGaAsP waveguide, Chi^(3) nonlinearity, spectral broadening, photon absorption

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5510 How Holton’s Thematic Analysis Can Help to Understand Why Fred Hoyle Never Accepted Big Bang Cosmology

Authors: Joao Barbosa

Abstract:

After an intense dispute between the big bang cosmology and its big rival, the steady-state cosmology, some important experimental observations, such as the determination of helium abundance in the universe and the discovery of the cosmic background radiation in the 1960s were decisive for the progressive and wide acceptance of big bang cosmology and the inevitable abandonment of steady-state cosmology. But, despite solid theoretical support and those solid experimental observations favorable to big bang cosmology, Fred Hoyle, one of the proponents of the steady-state and the main opponent of the idea of the big bang (which, paradoxically, himself he baptized), never gave up and continued to fight for the idea of a stationary (or quasi-stationary) universe until the end of his life, even after decades of widespread consensus around the big bang cosmology. We can try to understand this persistent attitude of Hoyle by applying Holton’s thematic analysis to cosmology. Holton recognizes in the scientific activity a dimension that, even unconscious or not assumed, is nevertheless very important in the work of scientists, in implicit articulation with the experimental and the theoretical dimensions of science. This is the thematic dimension, constituted by themata – concepts, methodologies, and hypotheses with a metaphysical, aesthetic, logical, or epistemological nature, associated both with the cultural context and the individual psychology of scientists. In practice, themata can be expressed through personal preferences and choices that guide the individual and collective work of scientists. Thematic analysis shows that big bang cosmology is mainly based on a set of themata consisting of evolution, finitude, life cycle, and change; the cosmology of the steady-state is based on opposite themata: steady-state, infinity, continuous existence, and constancy. The passionate controversy that these cosmological views carried out is part of an old cosmological opposition: the thematic opposition between an evolutionary view of the world (associated with Heraclitus) and a stationary view (associated with Parmenides). Personal preferences seem to have been important in this (thematic) controversy, and the thematic analysis that was developed shows that Hoyle is a very illustrative example of a life-long personal commitment to some themata, in this case to the opposite themata of the big bang cosmology. His struggle against the big bang idea was strongly based on philosophical and even religious reasons – which, in a certain sense and in a Holtonian perspective, is related to thematic preferences. In this personal and persistent struggle, Hoyle always refused the way how some experimental observations were considered decisive in favor of the big bang idea, arguing that the success of this idea is based on sociological and cultural prejudices. This Hoyle’s attitude is a personal thematic attitude, in which the acceptance or rejection of what is presented as proof or scientific fact is conditioned by themata: what is a proof or a scientific fact for one scientist is something yet to be established for another scientist who defends different or even opposites themata.

Keywords: cosmology, experimental observations, fred hoyle, interpretation, life-long personal commitment, Themata

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5509 Study of Magnetic Properties on the Corrosion Behavior and Influence of Temperature in Permanent Magnet (Nd-Fe-B) Used in PMSM

Authors: N. Yogal, C. Lehrmann

Abstract:

The use of Permanent magnet (PM) is increasing in the Permanent magnet synchronous machines (PMSM) to fulfill the requirement of high efficiency machines in modern industry. PMSM is widely used in industrial application, wind power plant and automotive industry. Since the PMSM are used in different environment condition, the long-term effect of NdFeB-based magnets at high temperatures and corrosion behavior has to be studied due to irreversible loss of magnetic properties. In this paper, the effect of magnetic properties due to corrosion and increasing temperature in the climatic chamber has been presented. The magnetic moment and magnetic field of the magnet were studied experimentally.

Keywords: permanent magnet (PM), NdFeB, corrosion behavior, temperature effect, Permanent magnet synchronous machine (PMSM)

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5508 Underdiagnosis of Supraclavicular Brachial Plexus Metastasis in the Shadow of Cervical Disc Herniation: Insights from a Lung Cancer Case Study

Authors: Eunhwa Jun

Abstract:

This case report describes the misdiagnosis of a patient who presented with right arm pain as cervical disc herniation. The patient had several underlying conditions, including hypertension, diabetes mellitus, liver cirrhosis, a history of lung cancer with left lower lobe lobectomy, and adjuvant chemoradiotherapy. An external cervical spine MRI revealed central protruding discs at the C4-5-6-7 levels. Despite treatment with medication and epidural blocks, the patient's pain persisted. A C-RACZ procedure was planned, but the patient's pain had worsened before admission. Using ultrasound, a brachial plexus block was attempted, but the brachial plexus eluded clear visualization, hinting at underlying neurological complexities. Chest CT revealed a new, large soft tissue mass in the right supraclavicular region with adjacent right axillary lymphadenopathy, leading to the diagnosis of metastatic squamous cell carcinoma. Palliative radiation therapy and chemotherapy were initiated as part of the treatment plan, and the patient's pain score decreased to 3 out of 10 on the Numeric Rating Scale (NRS), revealing the pain was due to metastatic lung cancer.

Keywords: supraclavicula brachial plexus metastasis, cervical disc herniation, brachial plexus block, metastatic lung cancer

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5507 Role of Environmental Focus in Legal Protection and Efficient Management of Wetlands in the Republic of Kazakhstan

Authors: K. R. Balabiyev, A. O. Kaipbayeva

Abstract:

The article discusses the legal framework of the government’s environmental function and analyzes the role of the national policy in protection of wetlands. The problem is of interest for it deals with the most important branch of economy–utilization of Kazakhstan’s natural resources, protection of health and environmental well being of the population. Development of a long-term environmental program addressing the protection of wetlands represents the final stage of the government’s environmental policy, and is a relatively new function for the public administration system. It appeared due to the environmental measures that require immediate decisions to be taken. It is an integral part of the effort in the field of management of state-owned natural resource, as well as of the measures aimed at efficient management of natural resources to avoid their early depletion or contamination.

Keywords: environmental focus, government’s environmental function, protection of wetlands, Kazakhstan

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5506 When Change Is the Only Constant: The Impact of Change Frequency and Diversity on Change Appraisal

Authors: Danika Pieters

Abstract:

Due to changing societal and economic demands, organizational change has become increasingly prevalent in work life. While a long time change research has focused on the effects of single discrete change events on different employee outcomes such as job satisfaction and organizational commitment, a nascent research stream has begun to look into the potential cumulative effects of change in the context of continuous intense reforms. This case study of a large Belgian public organization aims to add to this growing literature by examining how the frequency and diversity of past changes impact employees’ appraisals of a newly introduced change. Twelve hundred survey results were analyzed using standard ordinary least squares regression. Results showed a correlation between high past change frequency and diversity and a negative appraisal of the new change. Implications for practitioners and future research are discussed.

Keywords: change frequency, change diversity, organizational changes, change appraisal, change evaluation

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5505 Metastatic Ovarian Tumor Discovered Accidentally during Cesarean Section in a 34 Year Old Woman: A Case Report

Authors: Ghada E. Esheba, Ghufran Kheshaifaty, Kholoud Al-Harbi, Wafa'a Al-Harbi, Ala'a Al-Orabi, Moayad Turkistani

Abstract:

Krukenberg tumor is a rare metastatic ovarian carcinoma that usually occurs in female between 30 - 40 year old and rarely seen after menopause. Stomach is the most common primary site. Histopathological features of krukenberg tumors appear as diffuse stromal proliferation, mucus-production, and numerous signet-cells and these tumors spread mostly by lymphatic route. Treatment and prognostic factors are not well established. This study describes a 34 year old female with a unilateral ovarian mass discovered accidentally during cesarean section delivery and it was misdiagnosed as luteoma of pregnancy, but histopathological examination showed a diffuse infiltration of the ovary and omentum by signet ring cells. These findings were not correlated with luteoma of pregnancy or any other types of primary ovarian tumors like surface epithelial tumor, sex cord stromal tumor or germ cell tumor. However, after the analysis of immunohistochemical results (negative CK7, positive CK20 and CDX-2), the finding was the diagnostic of metastatic krukenberg tumor. Two weeks later, the patient was evaluated and a large gastric tumor was found in her stomach and she underwent gastrectomy.

Keywords: CK7, CK20, CDX-2, Krukenburg tumor, metastatic ovarian tumor

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5504 Study of Functional Relevant Conformational Mobility of β-2 Adrenoreceptor by Means of Molecular Dynamics Simulation

Authors: G. V. Novikov, V. S. Sivozhelezov, S. S. Kolesnikov, K. V. Shaitan

Abstract:

The study reports about the influence of binding of orthosteric ligands as well as point mutations on the conformational dynamics of β-2-adrenoreceptor. Using molecular dynamics simulation we found that there was a little fraction of active states of the receptor in its apo (ligand free) ensemble corresponded to its constitutive activity. Analysis of MD trajectories indicated that such spontaneous activation of the receptor is accompanied by the motion in intracellular part of its alpha-helices. Thus receptor’s constitutive activity directly results from its conformational dynamics. On the other hand the binding of a full agonist resulted in a significant shift of the initial equilibrium towards its active state. Finally, the binding of the inverse agonist stabilized the receptor in its inactive state. It is likely that the binding of inverse agonists might be a universal way of constitutive activity inhibition in vivo. Our results indicate that ligand binding redistribute pre-existing conformational degrees of freedom (in accordance to the Monod-Wyman-Changeux-Model) of the receptor rather than cause induced fit in it. Therefore, the ensemble of biologically relevant receptor conformations is encoded in its spatial structure, and individual conformations from that ensemble might be used by the cell in conformity with the physiological behaviour.

Keywords: seven-transmembrane receptors, constitutive activity, activation, x-ray crystallography, principal component analysis, molecular dynamics simulation

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5503 Stability Analysis of Tumor-Immune Fractional Order Model

Authors: Sadia Arshad, Yifa Tang, Dumitru Baleanu

Abstract:

A fractional order mathematical model is proposed that incorporate CD8+ cells, natural killer cells, cytokines and tumor cells. The tumor cells growth in the absence of an immune response is modeled by logistic law as it was the simplest form for which predictions also agreed with the experimental data. Natural Killer Cells are our first line of defense. NK cells directly kill tumor cells through several mechanisms, including the release of cytoplasmic granules containing perforin and granzyme, expression of tumor necrosis factor (TNF) family members. The effect of the NK cells on the tumor cell population is expressed with the product term. Rational form is used to describe interaction between CD8+ cells and tumor cells. A number of cytokines are produced by NKs, including tumor necrosis factor TNF, IFN, and interleukin (IL-10). Source term for cytokines is modeled by Michaelis-Menten form to indicate the saturated effects of the immune response. Stability of the equilibrium points is discussed for biologically significant values of bifurcation parameters. We studied the treatment of fractional order system by investigating analytical conditions of tumor eradication. Numerical simulations are presented to illustrate the analytical results.

Keywords: cancer model, fractional calculus, numerical simulations, stability analysis

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5502 Hypolipidemic and Antioxidant Effects of Mycelial Polysaccharides from Calocybe indica in Hyperlipidemic Rats Induced by High-Fat Diet

Authors: Govindan Sudha, Mathumitha Subramaniam, Alamelu Govindasamy, Sasikala Gunasekaran

Abstract:

The aim of this study was to investigate the protective effect of Hypsizygus ulmarius polysaccharides (HUP) on reducing oxidative stress, cognitive impairment and neurotoxicity in D-galactose induced aging mice. Mice were subcutaneously injected with D-galactose (150 mg/kg per day) for 6 weeks and were administered HUP simultaneously. Aged mice receiving vitamin E (100 mg/kg) served as positive control. Chronic administration of D-galactose significantly impaired cognitive performance oxidative defence and mitochondrial enzymes activities as compared to control group. The results showed that HUP (200 and 400 mg/kg) treatment significantly improved the learning and memory ability in Morris water maze test. Biochemical examination revealed that HUP significantly increased the decreased activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), mitochondrial enzymes-NADH dehydrogenase, malate dehydrogenase (MDH), isocitrate dehydrogenase (ICDH), Na+K+, Ca2+, Mg2+ATPase activities, elevated the lowered total anti-oxidation capability (TAOC), glutathione (GSH), vitamin C and decreased the raised acetylcholinesterase (AChE) activities, malondialdehyde (MDA), hydroperoxide (HPO), protein carbonyls (PCO), advanced oxidation protein products (AOPP) levels in brain of aging mice induced by D-gal in a dose-dependent manner. In conclusion, present study highlights the potential role of HUP against D-galactose induced cognitive impairment, biochemical and mitochondrial dysfunction in mice. In vitro studies on the effect of HUP on scavenging DPPH, ABTS, DMPD, OH radicals, reducing power, B-carotene bleaching and lipid peroxidation inhibition confirmed the free radical scavenging and antioxidant activity of HUP. The results suggest that HUP possesses anti-aging efficacy and may have potential in treatment of neurodegenerative diseases.

Keywords: aging, antioxidants, mushroom, neurotoxicity

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5501 The Eloquent Importance of Knowing Fyodor Dostoevsky: An Understanding of The Dilettante

Authors: Ravi Teja Mandapaka

Abstract:

Literary assonance and lexical consonance have always put the readers pondering, shirking away, at times too, and beefing on the baffling question that hardly invited any answer. ‘Why should we read Fyodor Mikhailovich Dostoevsky today?’ Does he, during a surreal life beneath his bruised and broken soul, writhing in pain, toying with the affirmatives of pleasure in an innate way, draw the readers any sheath of support? Alexithymia has ruled the time and space for a quite a long time as many a reader spent more time than required on reading his works of art in literature. Do his swirling theories of deism and laconic gushiness when put in black and white push us towards reading the lost pieces of exuberant dilettantism? With a view of that, and a hallucinated panorama of another, its best to say, thoughts and droughts’ glorious uncertainties in literature have come forward towards putting the pen on the eloquent importance of knowing Fyodor Dostoevsky, the Socrates of Literature.

Keywords: Dostoyevsky, dilettantism, gushiness, hallucinations, puissance

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5500 Effects of β-Glucan on the Release of Nitric Oxide by RAW264.7 Cells Stimulated with Escherichia coli Lipopolysaccharide

Authors: Eun Young Choi, So Hui Choe, Jin Yi Hyeon, Ji Young Jin, Bo Ram Keum, Jong Min Lim, Hyung Rae Cho, Kwang Keun Cho, In Soon Choi

Abstract:

This research analyzed the effect of β-glucan that is expected to alleviate the production of inflammatory mediator in macrophagocyte, which was processed by the lipopolysaccharide (LPS) of Escherichia, a pathogen related to allergy. The incubated layer was used for nitric oxide (NO) analysis. The DNA-binding activation of the small unit of NF-κB was measured using ELISA-based kit. In RAW264.7 cells that were vitalized by E.coli LPS, β-glucan inhibited both the combatant and rendering phases of inducible NO synthase (iNOS)-derived NO. β-glucan increased the expression of heme oxygenase-1 (HO-1) in the cell that was stimulated by E.coli LPS, and HO-1 activation was inhibited by SnPP. This shows that NO production induced by LPS is related to the inhibition effect of β-glucan. The phosphorylation of JNK and p38 induced by LPS were not influenced by β-glucan, and IκB-α decomposition was not influenced either. Instead, β-glucan remarkably inhibited the phosphorylation of STAT1 that was induced by E.coli LPS. Overall, β-glucan inhibited the production of NO in macrophagocyte that was vitalized by E.coli LPS through HO-1 induction and STAT1 pathways inhibition in this research. As the host inflammation reaction control by β-glucan weakens the progress of allergy, β-glucan can be used as an effective treatment method.

Keywords: β-glucan, lipopolysaccharide (LPS), nitric oxide (NO), RAW264.7 cells, STAT1

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5499 An Overview of New Era in Food Science and Technology

Authors: Raana Babadi Fathipour

Abstract:

Strict prerequisites of logical diaries united ought to demonstrate the exploratory information is (in)significant from the statistical point of view and has driven a soak increment within the utilization and advancement of the factual program. It is essential that the utilization of numerical and measurable strategies, counting chemometrics and many other factual methods/algorithms in nourishment science and innovation has expanded steeply within the final 20 a long time. Computational apparatuses accessible can be utilized not as it were to run factual investigations such as univariate and bivariate tests as well as multivariate calibration and improvement of complex models but also to run reenactments of distinctive scenarios considering a set of inputs or essentially making expectations for particular information sets or conditions. Conducting a fast look within the most legitimate logical databases (Pubmed, ScienceDirect, Scopus), it is conceivable to watch that measurable strategies have picked up a colossal space in numerous regions.

Keywords: food science, food technology, food safety, computational tools

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5498 Surface Passivation of Multicrystalline Silicon Solar Cell via Combination of LiBr/Porous Silicon and Grain Boundaies Grooving

Authors: Dimassi Wissem

Abstract:

In this work, we investigate the effect of combination between the porous silicon (PS) layer passivized with Lithium Bromide (LiBr) and grooving of grain boundaries (GB) in multi crystalline silicon. The grain boundaries were grooved in order to reduce the area of these highly recombining regions. Using optimized conditions, grooved GB's enable deep phosphorus diffusion and deep metallic contacts. We have evaluated the effects of LiBr on the surface properties of porous silicon on the performance of silicon solar cells. The results show a significant improvement of the internal quantum efficiency, which is strongly related to the photo-generated current. We have also shown a reduction of the surface recombination velocity and an improvement of the diffusion length after the LiBr process. As a result, the I–V characteristics under the dark and AM1.5 illumination were improved. It was also observed a reduction of the GB recombination velocity, which was deduced from light-beam-induced-current (LBIC) measurements. Such grooving in multi crystalline silicon enables passivization of GB-related defects. These results are discussed and compared to solar cells based on untreated multi crystalline silicon wafers.

Keywords: Multicrystalline silicon, LiBr, porous silicon, passivation

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5497 Modeling of Micro-Grid System Components Using MATLAB/Simulink

Authors: Mahmoud Fouad, Mervat Badr, Marwa Ibrahim

Abstract:

Micro-grid system is presently considered a reliable solution for the expected deficiency in the power required from future power systems. Renewable power sources such as wind, solar and hydro offer high potential of benign power for future micro-grid systems. Micro-Grid (MG) is basically a low voltage (LV) or medium voltage (MV) distribution network which consists of a number of called distributed generators (DG’s); micro-sources such as photovoltaic array, fuel cell, wind turbine etc. energy storage systems and loads; operating as a single controllable system, that could be operated in both grid-connected and islanded mode. The capacity of the DG’s is sufficient to support all; or most, of the load connected to the micro-grid. This paper presents a micro-grid system based on wind and solar power sources and addresses issues related to operation, control, and stability of the system. Using Matlab/Simulink, the system is modeled and simulated to identify the relevant technical issues involved in the operation of a micro-grid system based on renewable power generation units.

Keywords: micro-grid system, photovoltaic, wind turbine, energy storage, distributed generation, modeling

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5496 The Nonlinear Dynamic Response of a Rotor System Supported by Hydrodynamic Journal Bearings

Authors: Amira Amamou, Mnaouar Chouchane

Abstract:

This paper investigates the bifurcation and nonlinear behavior of two degrees of freedom model of a symmetrical balanced rigid rotor supported by two identical journal bearings. The fluid film hydrodynamic reactions are modeled by applying both the short and the long bearing approximation and using half Sommerfeld solution. A numerical integration of equations of the journal centre motion is presented to predict the presence and the size of stable or unstable limit cycles in the neighborhood of the stability critical speed. For their stability margins, a continuation method based on the predictor-corrector mechanism is used. The numerical results of responses show that stability and bifurcation behaviors of periodic motions depend strongly on bearing parameters and its dynamic characteristics.

Keywords: hydrodynamic journal bearing, nonlinear stability, continuation method, bifurcations

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5495 Performance Evaluation and Cost Analysis of Standby Systems

Authors: Mohammed A. Hajeeh

Abstract:

Pumping systems are an integral part of water desalination plants, their effective functioning is vital for the operation of a plant. In this research work, the reliability and availability of pressurized pumps in a reverse osmosis desalination plant are studied with the objective of finding configurations that provides optimal performance. Six configurations of a series system with different number of warm and cold standby components were examined. Closed form expressions for the mean time to failure (MTTF) and the long run availability are derived and compared under the assumption that the time between failures and repair times of the primary and standby components are exponentially distributed. Moreover, a cost/ benefit analysis is conducted in order to identify a configuration with the best performance and least cost. It is concluded that configurations with cold standby components are preferable especially when the pumps are of the size.

Keywords: availability, cost/benefit, mean time to failure, pumps

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5494 Simulation Model of Induction Heating in COMSOL Multiphysics

Authors: K. Djellabi, M. E. H. Latreche

Abstract:

The induction heating phenomenon depends on various factors, making the problem highly nonlinear. The mathematical analysis of this problem in most cases is very difficult and it is reduced to simple cases. Another knowledge of induction heating systems is generated in production environments, but these trial-error procedures are long and expensive. The numerical models of induction heating problem are another approach to reduce abovementioned drawbacks. This paper deals with the simulation model of induction heating problem. The simulation model of induction heating system in COMSOL Multiphysics is created. In this work we present results of numerical simulations of induction heating process in pieces of cylindrical shapes, in an inductor with four coils. The modeling of the inducting heating process was made with the software COMSOL Multiphysics Version 4.2a, for the study we present the temperature charts.

Keywords: induction heating, electromagnetic field, inductor, numerical simulation, finite element

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5493 Comparison between Simulation and Experimentally Observed Interactions between Two Different Sized Magnetic Beads in a Fluidic System

Authors: Olayinka Oduwole, Steve Sheard

Abstract:

The magnetic separation of biological cells using super-magnetic beads has been used widely for various bioassays. These bioassays can further be integrated with other laboratory components to form a biosensor which can be used for cell sorting, mixing, purification, transport, manipulation etc. These bio-sensing applications have also been facilitated by the wide availability of magnetic beads which range in size and magnetic properties produced by different manufacturers. In order to improve the efficiency and separation capabilities of these biosensors, it is important to determine the magnetic force induced velocities and interaction of beads within the magnetic field; this will help biosensor users choose the desired magnetic bead for their specific application. This study presents for the first time the interaction between a pair of different sized super-paramagnetic beads suspended in a static fluid moving within a uniform magnetic field using a modified finite-time-finite-difference scheme. A captured video was used to record the trajectory pattern and a good agreement was obtained between the simulated trajectories and the video data. The model is, therefore, a good approximation for predicting the velocities as well as the interaction between various magnetic particles which differ in size and magnetic properties for bio-sensing applications requiring a low concentration of magnetic beads.

Keywords: biosensor, magnetic field, magnetic separation, super-paramagnetic bead

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5492 The Impact of Bitcoin on Stock Market Performance

Authors: Oliver Takawira, Thembi Hope

Abstract:

This study will analyse the relationship between Bitcoin price movements and the Johannesburg stock exchange (JSE). The aim is to determine whether Bitcoin price movements affect the stock market performance. As crypto currencies continue to gain prominence as a safe asset during periods of economic distress, this raises the question of whether Bitcoin’s prosperity could affect investment in the stock market. To identify the existence of a short run and long run linear relationship, the study will apply the Autoregressive Distributed Lag Model (ARDL) bounds test and a Vector Error Correction Model (VECM) after testing the data for unit roots and cointegration using the Augmented Dicker Fuller (ADF) and Phillips-Perron (PP). The Non-Linear Auto Regressive Distributed Lag (NARDL) will then be used to check if there is a non-linear relationship between bitcoin prices and stock market prices.

Keywords: bitcoin, stock market, interest rates, ARDL

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5491 The Influence of C Element on the Phase Transformation in Weldment of Complex Stainless Steels 2507/316/316L

Authors: Lin Dong-Yih, Yang S. M., Huang B. W., Lian J. A.

Abstract:

Super duplex stainless steel has excellent mechanical properties and corrosion resistance. It becomes important structural material as its application has been extended to the fields such as renewable energy and the chemical industry because of its excellent properties. As examples are offshore wind power, solar cell machinery, and pipes in the chemical industry. The mechanical properties and corrosion resistance of super duplex stainless steel can be eliminated by welding due to the precipitation of the hard and brittle σ phase, which is rich of chromium, and molybdenum elements. This paper studies the influence of carbon element on the phase transformation of -ferrite and σ phase in 2507 super duplex stainless steel. The 2507 will be under argon gas protection welded with 316 and 316L extra low carbon stainless steel separately. The microstructural phases of stainless steels before and after welding, in fusion, heat affected zones, and base material will be studied via X-ray, OM, SEM, EPMA i.e. their quantity, size, distribution, and morphology. The influences of diffusion by carbon element will be compared according to the microstructures, hardness, and corrosion tests.

Keywords: complex stainless steel, welding, phase formation, carbon element, sigma phase, delta ferrite

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5490 Three Issues for Integrating Artificial Intelligence into Legal Reasoning

Authors: Fausto Morais

Abstract:

Artificial intelligence has been widely used in law. Programs are able to classify suits, to identify decision-making patterns, to predict outcomes, and to formalize legal arguments as well. In Brazil, the artificial intelligence victor has been classifying cases to supreme court’s standards. When those programs act doing those tasks, they simulate some kind of legal decision and legal arguments, raising doubts about how artificial intelligence can be integrated into legal reasoning. Taking this into account, the following three issues are identified; the problem of hypernormatization, the argument of legal anthropocentrism, and the artificial legal principles. Hypernormatization can be seen in the Brazilian legal context in the Supreme Court’s usage of the Victor program. This program generated efficiency and consistency. On the other hand, there is a feasible risk of over standardizing factual and normative legal features. Then legal clerks and programmers should work together to develop an adequate way to model legal language into computational code. If this is possible, intelligent programs may enact legal decisions in easy cases automatically cases, and, in this picture, the legal anthropocentrism argument takes place. Such an argument argues that just humans beings should enact legal decisions. This is so because human beings have a conscience, free will, and self unity. In spite of that, it is possible to argue against the anthropocentrism argument and to show how intelligent programs may work overcoming human beings' problems like misleading cognition, emotions, and lack of memory. In this way, intelligent machines could be able to pass legal decisions automatically by classification, as Victor in Brazil does, because they are binding by legal patterns and should not deviate from them. Notwithstanding, artificial intelligent programs can be helpful beyond easy cases. In hard cases, they are able to identify legal standards and legal arguments by using machine learning. For that, a dataset of legal decisions regarding a particular matter must be available, which is a reality in Brazilian Judiciary. Doing such procedure, artificial intelligent programs can support a human decision in hard cases, providing legal standards and arguments based on empirical evidence. Those legal features claim an argumentative weight in legal reasoning and should serve as references for judges when they must decide to maintain or overcome a legal standard.

Keywords: artificial intelligence, artificial legal principles, hypernormatization, legal anthropocentrism argument, legal reasoning

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5489 Quality by Design in the Optimization of a Fast HPLC Method for Quantification of Hydroxychloroquine Sulfate

Authors: Pedro J. Rolim-Neto, Leslie R. M. Ferraz, Fabiana L. A. Santos, Pablo A. Ferreira, Ricardo T. L. Maia-Jr., Magaly A. M. Lyra, Danilo A F. Fonte, Salvana P. M. Costa, Amanda C. Q. M. Vieira, Larissa A. Rolim

Abstract:

Initially developed as an antimalarial agent, hydroxychloroquine (HCQ) sulfate is often used as a slow-acting antirheumatic drug in the treatment of disorders of connective tissue. The United States Pharmacopeia (USP) 37 provides a reversed-phase HPLC method for quantification of HCQ. However, this method was not reproducible, producing asymmetric peaks in a long analysis time. The asymmetry of the peak may cause an incorrect calculation of the concentration of the sample. Furthermore, the analysis time is unacceptable, especially regarding the routine of a pharmaceutical industry. The aiming of this study was to develop a fast, easy and efficient method for quantification of HCQ sulfate by High Performance Liquid Chromatography (HPLC) based on the Quality by Design (QbD) methodology. This method was optimized in terms of peak symmetry using the surface area graphic as the Design of Experiments (DoE) and the tailing factor (TF) as an indicator to the Design Space (DS). The reference method used was that described at USP 37 to the quantification of the drug. For the optimized method, was proposed a 33 factorial design, based on the QbD concepts. The DS was created with the TF (in a range between 0.98 and 1.2) in order to demonstrate the ideal analytical conditions. Changes were made in the composition of the USP mobile-phase (USP-MP): USP-MP: Methanol (90:10 v/v, 80:20 v/v and 70:30 v/v), in the flow (0.8, 1.0 and 1.2 mL) and in the oven temperature (30, 35, and 40ºC). The USP method allowed the quantification of drug in a long time (40-50 minutes). In addition, the method uses a high flow rate (1,5 mL.min-1) which increases the consumption of expensive solvents HPLC grade. The main problem observed was the TF value (1,8) that would be accepted if the drug was not a racemic mixture, since the co-elution of the isomers can become an unreliable peak integration. Therefore, the optimization was suggested in order to reduce the analysis time, aiming a better peak resolution and TF. For the optimization method, by the analysis of the surface-response plot it was possible to confirm the ideal setting analytical condition: 45 °C, 0,8 mL.min-1 and 80:20 USP-MP: Methanol. The optimized HPLC method enabled the quantification of HCQ sulfate, with a peak of high resolution, showing a TF value of 1,17. This promotes good co-elution of isomers of the HCQ, ensuring an accurate quantification of the raw material as racemic mixture. This method also proved to be 18 times faster, approximately, compared to the reference method, using a lower flow rate, reducing even more the consumption of the solvents and, consequently, the analysis cost. Thus, an analytical method for the quantification of HCQ sulfate was optimized using QbD methodology. This method proved to be faster and more efficient than the USP method, regarding the retention time and, especially, the peak resolution. The higher resolution in the chromatogram peaks supports the implementation of the method for quantification of the drug as racemic mixture, not requiring the separation of isomers.

Keywords: analytical method, hydroxychloroquine sulfate, quality by design, surface area graphic

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5488 Development of Plantar Insoles Reinforcement Using Biocomposites

Authors: A. C. Vidal, D. R. Mulinari, C. F. Bandeira, S. R. Montoro

Abstract:

Due to the great effort suffered by foot during movement, is of great importance to count on a shoe that has a proper structure and excellent support tread to prevent the immediate and long-term consequences in all parts of the body. In this sense, new reinforcements of insoles with high impact absorption were developed in this work, from a polyurethane (PU) biocomposite derived from castor oil reinforced or not with palm fibers. These insoles have been obtained from the mixture with polyol prepolymer (diisocyanate) and subsequently were evaluated morphologically, mechanically and by thermal analysis. The results revealed that the biocomposites showed lower flexural strength, higher impact strength and open interconnected pores in their microstructure, but with smaller cells and degradation temperature slightly higher compared to the marketed material, showing interesting properties for a possible application as reinforcement of insoles.

Keywords: composite, polyurethane insole, palm fibers, plantar insoles reinforcement

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5487 The Keys to Innovation: Defining and Evaluating Attributes that Measure Innovation Capabilities

Authors: Mohammad Samarah, Benjamin Stark, Jennifer Kindle, Langley Payton

Abstract:

Innovation is a key driver for companies, society, and economic growth. However, assessing and measuring innovation for individuals as well as organizations remains difficult. Our i5-Score presented in this study will help to overcome this difficulty and facilitate measuring the innovation potential. The score is based on a framework we call the 5Gs of innovation which defines specific innovation attributes. Those are 1) the drive for long-term goals 2) the audacity to generate new ideas, 3) the openness to share ideas with others, 4) the ability to grow, and 5) the ability to maintain high levels of optimism. To validate the i5-Score, we conducted a study at Florida Polytechnic University. The results show that the i5-Score is a good measure reflecting the innovative mindset of an individual or a group. Thus, the score can be utilized for evaluating, refining and enhancing innovation capabilities.

Keywords: Change Management, Innovation Attributes, Organizational Development, STEM and Venture Creation

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5486 Iron Doped Biomaterial Calcium Borate: Synthesis and Characterization

Authors: G. Çelik Gül, F. Kurtuluş

Abstract:

Colemanite is the most common borate mineral, and the main source of the boron required by plants, human, and earth. Transition metals exhibit optical and physical properties such as; non-linear optical character, structural diversity, thermal stability, long cycle life and luminescent radiation. The doping of colemanite with a transition metal, bring it very interesting and attractive properties which make them applicable in industry. Iron doped calcium borate was synthesized by conventional solid state method at 1200 °C for 12 h with a systematic pathway. X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy/energy dispersive analyze (SEM/EDS) were used to characterize structural and morphological properties. Also, thermal properties were recorded by thermogravimetric-differential thermal analysis (TG/DTA). 

Keywords: colemanite, conventional synthesis, powder x-ray diffraction, borates

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5485 An Investigation of Anticancer Fluorinated Aza-Heterocycles

Authors: Darya O. Prima, Elena V. Vorontsova, Yuri G. Slizhov, Andrey V. Zibarev

Abstract:

A broad family of carbocycle-fluorinated aza-heterocycles including 1,3-benzodiazoles (benzimidazoles), 1,2,3-benzotriazoles, 2,1,3-benzothia/selenadiazoles and 1,4-benzodiazines (quinoxalines) was synthesized in the unified way and assessed for cytotoxicity towards the Hep2 (laryngeal epidermoid carcinoma, a kind of oral cancer) cells. The diazoles, triazoles and selenadiazoles revealed low medium inhibitory concentrations IC50 = 2.2-26.4 µМ and induced the cells’ apoptosis at low concentrations C = 1-25 µМ. For selenadiazoles, cell death dynamics was observed already in the first hours after the treatment. Replacement of one atom F by group Me2N in some cases enlarged apoptotic activity of the compounds towards the Hep2 cells. In contrast, the archetypal (i.e. non-fluorinated) 1,3-benzodiazole, 1,2,3-benzotriazole and 2,1,3-benzoselenadiazole were low toxic (IC50 > 100 µM) and induced apoptosis only at high concentrations. The chlorinated congeners of the heterocycles under discussion were highly toxic towards the Hep2 cells but revealed insignificant ability to induce their apoptosis. Overall, the findings above suggest that fluorinated 1,3-benzodiazole, 1,2,3-benzotriazole and 2,1,3-benzoselenadiazole derivatives can be considered as potential anticancer drugs. For the laryngeal epidermoid carcinoma (for which, according to available statistics, the five-year survival rate remained ~50% during the past 30 years), it is especially important since surgical treatment is seriously complicated here thus encouraging medicament one.

Keywords: Apoptosis, aza-heterocycles, cytotoxicity, fluorinated, Hep2 cells, synthesis

Procedia PDF Downloads 329