Search results for: loss functions
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5693

Search results for: loss functions

5123 A Study on Behaviour of Normal Strength Concrete and High Strength Concrete Subjected to Elevated Temperatures

Authors: Butchi Kameswara Rao Chittem, Rooban Kumar

Abstract:

Cement concrete is a complex mixture of different materials. Concrete is believed to have a good fire resistance. Behaviour of concrete depends on its mix proportions and its constituent materials when it is subjected to elevated temperatures. Loss in compressive strength, loss in weight or mass, change in colour and spall of concrete are reported in literature as effects of elevated temperature on concrete. In this paper results are reported on the behaviour of normal strength concrete and high strength concrete subjected to temperatures 200°C, 400°C, 600°C, and 800°C and different cooling regimes viz. air cooling, water quenching. Rebound hammer test was also conducted to study the changes in surface hardness of concrete specimens subjected to elevated temperatures.

Keywords: normal strength concrete, high-strength concrete, temperature, NDT

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5122 A Boundary Backstepping Control Design for 2-D, 3-D and N-D Heat Equation

Authors: Aziz Sezgin

Abstract:

We consider the problem of stabilization of an unstable heat equation in a 2-D, 3-D and generally n-D domain by deriving a generalized backstepping boundary control design methodology. To stabilize the systems, we design boundary backstepping controllers inspired by the 1-D unstable heat equation stabilization procedure. We assume that one side of the boundary is hinged and the other side is controlled for each direction of the domain. Thus, controllers act on two boundaries for 2-D domain, three boundaries for 3-D domain and ”n” boundaries for n-D domain. The main idea of the design is to derive ”n” controllers for each of the dimensions by using ”n” kernel functions. Thus, we obtain ”n” controllers for the ”n” dimensional case. We use a transformation to change the system into an exponentially stable ”n” dimensional heat equation. The transformation used in this paper is a generalized Volterra/Fredholm type with ”n” kernel functions for n-D domain instead of the one kernel function of 1-D design.

Keywords: backstepping, boundary control, 2-D, 3-D, n-D heat equation, distributed parameter systems

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5121 Can Illusions of Control Make Us Happy?

Authors: Martina Kaufmann, Thomas Goetz, Anastasiya A. Lipnevich, Reinhard Pekrun

Abstract:

Positive emotions have been shown to benefit from optimistic perceptions, even if these perceptions are illusory. The current research investigated the impact of illusions of control on positive emotions. There is empirical evidence showing that people are more emotionally attentive to losses than to gains. Hence, we expected that, compared to gains, losses in illusory control would have a stronger impact on positive emotions. The results of two experimental studies support this assumption: Participants who experienced gains in illusory control showed no substantial change in positive emotions. However, positive emotions decreased when they perceived a loss in illusory control. These results suggest that a loss of illusory control (but not a gain thereof) mediates the impact of the situation on individuals’ positive emotions. Implications for emotion theory and practice are discussed.

Keywords: cognitive appraisal, control, illusions, optimism, positive emotions

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5120 Immiscible Polymer Blends with Controlled Nanoparticle Location for Excellent Microwave Absorption: A Compartmentalized Approach

Authors: Sourav Biswas, Goutam Prasanna Kar, Suryasarathi Bose

Abstract:

In order to obtain better materials, control in the precise location of nanoparticles is indispensable. It was shown here that ordered arrangement of nanoparticles, possessing different characteristics (electrical/magnetic dipoles), in the blend structure can result in excellent microwave absorption. This is manifested from a high reflection loss of ca. -67 dB for the best blend structure designed here. To attenuate electromagnetic radiations, the key parameters i.e. high electrical conductivity and large dielectric/magnetic loss are targeted here using a conducting inclusion [multiwall carbon nanotubes, MWNTs]; ferroelectric nanostructured material with associated relaxations in the GHz frequency [barium titanate, BT]; and a loss ferromagnetic nanoparticles [nickel ferrite, NF]. In this study, bi-continuous structures were designed using 50/50 (by wt) blends of polycarbonate (PC) and polyvinylidene fluoride (PVDF). The MWNTs was modified using an electron acceptor molecule; a derivative of perylenediimide, which facilitates π-π stacking with the nanotubes and stimulates efficient charge transport in the blends. The nanoscopic materials have specific affinity towards the PVDF phase. Hence, by introducing surface-active groups, ordered arrangement can be tailored. To accomplish this, both BT and NF was first hydroxylated followed by introducing amine-terminal groups on the surface. The latter facilitated in nucleophilic substitution reaction with PC and resulted in their precise location. In this study, we have shown for the first time that by compartmentalized approach, superior EM attenuation can be achieved. For instance, when the nanoparticles were localized exclusively in the PVDF phase or in both the phases, the minimum reflection loss was ca. -18 dB (for MWNT/BT mixture) and -29 dB (for MWNT/NF mixture), and the shielding was primarily through reflection. Interestingly, by adopting the compartmentalized approach where in, the lossy materials were in the PC phase and the conducting inclusion (MWNT) in PVDF, an outstanding reflection loss of ca. -57 dB (for BT and MWNT combination) and -67 dB (for NF and MWNT combination) was noted and the shielding was primarily through absorption. Thus, the approach demonstrates that nanoscopic structuring in the blends can be achieved under macroscopic processing conditions and this strategy can further be explored to design microwave absorbers.

Keywords: barium titanate, EMI shielding, MWNTs, nickel ferrite

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5119 Street Begging: A Loss of Human Resource in Nigeria

Authors: Sulaiman Kassim Ibrahim

Abstract:

Human Resource is one of the most important elements in any country. They are very important in actualizing the potential of every sector in the country, i.e Agric, Education, Finance, Judiciary and all formal and informal sectors. The purpose of this study is to investigate the loss of human resource in Nigeria through street begging. The study used intensive literature review. Finding from the review indicate that a significant number of human resource are into street begging in the country undeveloped and untapped. The paper recommend that policy should be initiated to discourage street begging, develop this resource through education and empowerment, stop rural-urban migration by providing infrastructure in the rural areas and abolish informal (Almajiri or beggars school) and transform it into formal school.

Keywords: human resource, street begging, Nigeria, Almajiri

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5118 Laboratory and Numerical Hydraulic Modelling of Annular Pipe Electrocoagulation Reactors

Authors: Alejandra Martin-Dominguez, Javier Canto-Rios, Velitchko Tzatchkov

Abstract:

Electrocoagulation is a water treatment technology that consists of generating coagulant species in situ by electrolytic oxidation of sacrificial anode materials triggered by electric current. It removes suspended solids, heavy metals, emulsified oils, bacteria, colloidal solids and particles, soluble inorganic pollutants and other contaminants from water, offering an alternative to the use of metal salts or polymers and polyelectrolyte addition for breaking stable emulsions and suspensions. The method essentially consists of passing the water being treated through pairs of consumable conductive metal plates in parallel, which act as monopolar electrodes, commonly known as ‘sacrificial electrodes’. Physicochemical, electrochemical and hydraulic processes are involved in the efficiency of this type of treatment. While the physicochemical and electrochemical aspects of the technology have been extensively studied, little is known about the influence of the hydraulics. However, the hydraulic process is fundamental for the reactions that take place at the electrode boundary layers and for the coagulant mixing. Electrocoagulation reactors can be open (with free water surface) and closed (pressurized). Independently of the type of rector, hydraulic head loss is an important factor for its design. The present work focuses on the study of the total hydraulic head loss and flow velocity and pressure distribution in electrocoagulation reactors with single or multiple concentric annular cross sections. An analysis of the head loss produced by hydraulic wall shear friction and accessories (minor head losses) is presented, and compared to the head loss measured on a semi-pilot scale laboratory model for different flow rates through the reactor. The tests included laminar, transitional and turbulent flow. The observed head loss was compared also to the head loss predicted by several known conceptual theoretical and empirical equations, specific for flow in concentric annular pipes. Four single concentric annular cross section and one multiple concentric annular cross section reactor configuration were studied. The theoretical head loss resulted higher than the observed in the laboratory model in some of the tests, and lower in others of them, depending also on the assumed value for the wall roughness. Most of the theoretical models assume that the fluid elements in all annular sections have the same velocity, and that flow is steady, uniform and one-dimensional, with the same pressure and velocity profiles in all reactor sections. To check the validity of such assumptions, a computational fluid dynamics (CFD) model of the concentric annular pipe reactor was implemented using the ANSYS Fluent software, demonstrating that pressure and flow velocity distribution inside the reactor actually is not uniform. Based on the analysis, the equations that predict better the head loss in single and multiple annular sections were obtained. Other factors that may impact the head loss, such as the generation of coagulants and gases during the electrochemical reaction, the accumulation of hydroxides inside the reactor, and the change of the electrode material with time, are also discussed. The results can be used as tools for design and scale-up of electrocoagulation reactors, to be integrated into new or existing water treatment plants.

Keywords: electrocoagulation reactors, hydraulic head loss, concentric annular pipes, computational fluid dynamics model

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5117 Effects of a 6-Month Caloric Restriction Induced-Weight Loss Program in Obese Postmenopausal Women with and without the Metabolic Syndrome: A MONET Study

Authors: Ahmed Ghachem, Denis Prud’homme, Rémi-Rabasa-Lhoret, M. Brochu

Abstract:

Objective: To compare the effects of a CR on body composition, lipid profile and glucose homeostasis in obese postmenopausal women with and without MetS. Methods: Secondary analyses were performed on seventy-three inactive obese postmenopausal women (age: 57.7 ± 4.8 yrs; body mass index: 32.4 ± 4.6 kg/m2) who participated in the 6-month caloric restriction arm of a study of the Montreal-Ottawa New Emerging Team. The harmonized MetS definition was used to categorized participants with MetS [n = 20, 27.39%] and without MetS [n = 53, 72.61%]. Variables of interest were: body composition (DXA), body fat distribution (CT scan), glucose homeostasis at the fasting state and during a euglycemic/hyperinsulinemic clamp, fasting lipids and resting blood pressure. Results: By design, the MetS group had a worse cardiometabolic profile; while both groups were comparable for age. Fifty-five patients out of seventy-three displayed no change in MetS status after the intervention. Twelve participants out of twenty (or 60.0%) in the MetS group had no more MetS after weight loss (P= NS); while six participants out of fifty three (or 11.3%) in the other group developed the MetS after the intervention (P= NS). Overall, indices of body composition and body fat distribution improved significantly and similarly in both groups (P between 0.03 and 0.0001). Furthermore, with the exception of triglyceride levels and triglycerides/HDL-C ratio, which decrease significantly more in the MetS group (P ≤ 0.05), no difference was observed between groups for the other variables of the cardiometabolic profile. Conclusion: Despite no overall significant effects on MetS, heterogeneous results were obtained in response to weight loss in the present study; with some improving the MetS while other displaying deteriorations. Further studies are needed in order to identify factors and phenotypes associated with positive and negative cardiometabolic responses to CR intervention.

Keywords: menopause, obesity, physical inactivity, metabolic syndrome, caloric restriction, weight loss

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5116 Welfare Dynamics and Food Prices' Changes: Evidence from Landholding Groups in Rural Pakistan

Authors: Lubna Naz, Munir Ahmad, G. M. Arif

Abstract:

This study analyzes static and dynamic welfare impacts of food price changes for various landholding groups in Pakistan. The study uses three classifications of land ownership, landless, small landowners and large landowners, for analysis. The study uses Panel Survey, Pakistan Rural Household Survey (PRHS) of Pakistan Institute of Development Economics Islamabad, of rural households from two largest provinces (Sindh and Punjab) of Pakistan. The study uses all three waves (2001, 2004 and 2010) of PRHS. This research work makes three important contributions in literature. First, this study uses Quadratic Almost Ideal Demand System (QUAIDS) to estimate demand functions for eight food groups-cereals, meat, milk and milk products, vegetables, cooking oil, pulses and other food. The study estimates food demand functions with Nonlinear Seemingly Unrelated (NLSUR), and employs Lagrange Multiplier and test on the coefficient of squared expenditure term to determine inclusion of squared expenditure term. Test results support the inclusion of squared expenditure term in the food demand model for each of landholding groups (landless, small landowners and large landowners). This study tests for endogeneity and uses control function for its correction. The problem of observed zero expenditure is dealt with a two-step procedure. Second, it creates low price and high price periods, based on literature review. It uses elasticity coefficients from QUAIDS to analyze static and dynamic welfare effects (first and second order Tylor approximation of expenditure function is used) of food price changes across periods. The study estimates compensation variation (CV), money metric loss from food price changes, for landless, small and large landowners. Third, this study compares the findings on welfare implications of food price changes based on QUAIDS with the earlier research in Pakistan, which used other specification of the demand system. The findings indicate that dynamic welfare impacts of food price changes are lower as compared to static welfare impacts for all landholding groups. The static and dynamic welfare impacts of food price changes are highest for landless. The study suggests that government should extend social security nets to landless poor and categorically to vulnerable landless (without livestock) to redress the short-term impact of food price increase. In addition, the government should stabilize food prices and particularly cereal prices in the long- run.

Keywords: QUAIDS, Lagrange multiplier, NLSUR, and Tylor approximation

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5115 DG Allocation to Reduce Production Cost by Reducing Losses in Radial Distribution Systems Using Fuzzy

Authors: G. V. Siva Krishna Rao, B. Srinivasa Rao

Abstract:

Electrical energy is vital in every aspect of day-to-day life. Keen interest is taken on all possible sources of energy from which it can be generated and this led to the encouragement of generating electrical power using renewable energy resources such as solar, tidal waves and wind energy. Due to the increasing interest on renewable sources in recent times, the studies on integration of distributed generation to the power grid have rapidly increased. Distributed Generation (DG) is a promising solution to many power system problems such as voltage regulation, power loss and reduction in operational cost, etc. To reduce production cost, it is important to minimize the losses by determining the location and size of local generators to be placed in the radial distribution systems. In this paper, reduction of production cost by optimal size of DG unit operated at optimal power factor is dealt. The optimal size of the DG unit is calculated analytically using approximate reasoning suitable nodes and DG placement to minimize production cost with minimum loss is determined by fuzzy technique. Total Cost of Power generation is compared with and without DG unit for 1 year duration. The suggested method is programmed under MATLAB software and is tested on IEEE 33 bus system and the results are presented.

Keywords: distributed generation, operational cost, exact loss formula, optimum size, optimum location

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5114 Portfolio Optimization under a Hybrid Stochastic Volatility and Constant Elasticity of Variance Model

Authors: Jai Heui Kim, Sotheara Veng

Abstract:

This paper studies the portfolio optimization problem for a pension fund under a hybrid model of stochastic volatility and constant elasticity of variance (CEV) using asymptotic analysis method. When the volatility component is fast mean-reverting, it is able to derive asymptotic approximations for the value function and the optimal strategy for general utility functions. Explicit solutions are given for the exponential and hyperbolic absolute risk aversion (HARA) utility functions. The study also shows that using the leading order optimal strategy results in the value function, not only up to the leading order, but also up to first order correction term. A practical strategy that does not depend on the unobservable volatility level is suggested. The result is an extension of the Merton's solution when stochastic volatility and elasticity of variance are considered simultaneously.

Keywords: asymptotic analysis, constant elasticity of variance, portfolio optimization, stochastic optimal control, stochastic volatility

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5113 Selective Attention as a Search for the Deceased during the Mourning Process

Authors: Sonia Sirtoli Färber

Abstract:

Objective: This study aims to investigate selective attention in the process of mourning, as a normal reaction to loss. Method: In order to develop this research, we used a systematic bibliographic review, following the process of investigation, cataloging, careful evaluation and synthesis of the documentation, associated with the method of thanatological hemenutics proposed by Elisabeth Kübler-Ross. Conclusion: After a significant loss, especially the death of a loved one or family member, it is normal for the mourner, motivated by absence, to have a false perception of the presence of the deceased. This phenomenon happens whenever the mourner is in the middle of the crowd, because his selective attention causes him to perceive physical characteristics, tone of voice, or feel fragrance of the perfume that the deceased possessed. Details characterizing the dead are perceived by the mourner because he seeks the presence in the absence.

Keywords: Elisabeth Kübler-Ross, mourning, selective attention, thanatology

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5112 Predicting Loss of Containment in Surface Pipeline using Computational Fluid Dynamics and Supervised Machine Learning Model to Improve Process Safety in Oil and Gas Operations

Authors: Muhammmad Riandhy Anindika Yudhy, Harry Patria, Ramadhani Santoso

Abstract:

Loss of containment is the primary hazard that process safety management is concerned within the oil and gas industry. Escalation to more serious consequences all begins with the loss of containment, starting with oil and gas release from leakage or spillage from primary containment resulting in pool fire, jet fire and even explosion when reacted with various ignition sources in the operations. Therefore, the heart of process safety management is avoiding loss of containment and mitigating its impact through the implementation of safeguards. The most effective safeguard for the case is an early detection system to alert Operations to take action prior to a potential case of loss of containment. The detection system value increases when applied to a long surface pipeline that is naturally difficult to monitor at all times and is exposed to multiple causes of loss of containment, from natural corrosion to illegal tapping. Based on prior researches and studies, detecting loss of containment accurately in the surface pipeline is difficult. The trade-off between cost-effectiveness and high accuracy has been the main issue when selecting the traditional detection method. The current best-performing method, Real-Time Transient Model (RTTM), requires analysis of closely positioned pressure, flow and temperature (PVT) points in the pipeline to be accurate. Having multiple adjacent PVT sensors along the pipeline is expensive, hence generally not a viable alternative from an economic standpoint.A conceptual approach to combine mathematical modeling using computational fluid dynamics and a supervised machine learning model has shown promising results to predict leakage in the pipeline. Mathematical modeling is used to generate simulation data where this data is used to train the leak detection and localization models. Mathematical models and simulation software have also been shown to provide comparable results with experimental data with very high levels of accuracy. While the supervised machine learning model requires a large training dataset for the development of accurate models, mathematical modeling has been shown to be able to generate the required datasets to justify the application of data analytics for the development of model-based leak detection systems for petroleum pipelines. This paper presents a review of key leak detection strategies for oil and gas pipelines, with a specific focus on crude oil applications, and presents the opportunities for the use of data analytics tools and mathematical modeling for the development of robust real-time leak detection and localization system for surface pipelines. A case study is also presented.

Keywords: pipeline, leakage, detection, AI

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5111 Optimal Design of Redundant Hybrid Manipulator for Minimum Singularity

Authors: Arash Rahmani, Ahmad Ghanbari, Abbas Baghernezhad, Babak Safaei

Abstract:

In the design of parallel manipulators, usually mean value of a dexterity measure over the workspace volume is considered as the objective function to be used in optimization algorithms. The mentioned indexes in a hybrid parallel manipulator (HPM) are quite complicated to solve thanks to infinite solutions for every point within the workspace of the redundant manipulators. In this paper, spatial isotropic design axioms are extended as a well-known method for optimum design of manipulators. An upper limit for the isotropy measure of HPM is calculated and instead of computing and minimizing isotropy measure, minimizing the obtained limit is considered. To this end, two different objective functions are suggested which are obtained from objective functions of comprising modules. Finally, by using genetic algorithm (GA), the best geometric parameters for a specific hybrid parallel robot which is composed of two modified Gough-Stewart platforms (MGSP) are achieved.

Keywords: hybrid manipulator, spatial isotropy, genetic algorithm, optimum design

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5110 A Corpus-Based Study of Subtitling Religious Words into Arabic

Authors: Yousef Sahari, Eisa Asiri

Abstract:

Hollywood films are produced in an open and liberal context, and when subtitling for a more conservative and closed society such as an Arabic society, religious words can pose a thorny challenge for subtitlers. Using a corpus of 90 Hollywood films released between 2000 and 2018 and applying insights from Descriptive Translation Studies (Toury, 1995, 2012) and the dichotomy of domestication and foreignization, this paper investigates three main research questions: (1) What are the dominant religious terms and functions in the English subtitles? (2) What are the dominant translation strategies used in the translation of religious words? (3) Do these strategies tend to be SL-oriented or TL-oriented (domesticating or foreignising)? To answer the research questions above, a quantitative and qualitative analysis of the corpus is conducted, in which the researcher adopts a self-designed, parallel, aligned corpus of ninety films and their Arabic subtitles. A quantitative analysis is performed to compare the frequencies and distribution of religious words, their functions, and the translation strategies employed by the subtitlers of ninety films, with the aim of identifying similarities or differences in addition to identifying the impact of functions of religious terms on the use of subtitling strategies. Based on the quantitative analysis, a qualitative analysis is performed to identify any translational patterns in Arabic translations of religious words and the possible reasons for subtitlers’ choices. The results show that the function of religious words has a strong influence on the choice of subtitling strategies. Also, it is found that foreignization strategies are applied in about two-thirds of the total occurrences of religious words.

Keywords: religious terms, subtitling, audiovisual translation, modern standard arabic, subtitling strategies, english-arabic subtitling

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5109 Use and Relationship of Shell Nouns as Cohesive Devices in the Quality of Second Language Writing

Authors: Kristine D. de Leon, Junifer A. Abatayo, Jose Cristina M. Pariña

Abstract:

The current study is a comparative analysis of the use of shell nouns as a cohesive device (CD) in an English for Second Language (ESL) setting in order to identify their use and relationship in the quality of second language (L2) writing. As these nouns were established to anticipate the meaning within, across or outside the text, their use has fascinated writing researchers. The corpus of the study included published articles from reputable journals and graduate students’ papers in order to analyze the frequency of shell nouns using “highly prevalent” nouns in the academic community, to identify the different lexicogrammatical patterns where these nouns occur and to the functions connected with these patterns. The result of the study implies that published authors used more shell nouns in their paper than graduate students. However, the functions of the different lexicogrammatical patterns for the frequently occurring shell nouns are somewhat similar. These results could help students in enhancing the cohesion of their text and in comprehending it.

Keywords: anaphoric, cataphoric, lexico-grammatical, shell nouns

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5108 Computational Fluid Dynamics-Coupled Optimisation Strategy for Aerodynamic Design

Authors: Anvar Atayev, Karl Steinborn, Aleksander Lovric, Saif Al-Ibadi, Jorg Fliege

Abstract:

In this paper, we present results obtained from optimising the aerodynamic performance of aerostructures in external ow. The optimisation method used was developed to efficiently handle multi-variable problems with numerous black-box objective functions and constraints. To demonstrate these capabilities, a series of CFD problems were considered; (1) a two-dimensional NACA aerofoil with three variables, (2) a two-dimensional morphing aerofoil with 17 variables, and (3) a three-dimensional morphing aeroplane tail with 33 variables. The objective functions considered were related to combinations of the mean aerodynamic coefficients, as well as their relative variations/oscillations. It was observed that for each CFD problem, an improved objective value was found. Notably, the scale-up in variables for the latter problems did not greatly hinder optimisation performance. This makes the method promising for scaled-up CFD problems, which require considerable computational resources.

Keywords: computational fluid dynamics, optimisation algorithms, aerodynamic design, engineering design

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5107 A New Microstrip Diplexer Using Coupled Stepped Impedance Resonators

Authors: A. Chinig, J. Zbitou, A. Errkik, L. Elabdellaoui, A. Tajmouati, A. Tribak, M. Latrach

Abstract:

This paper presents a new structure of microstrip band pass filter (BPF) based on coupled stepped impedance resonators. Each filter consists of two coupled stepped impedance resonators connected to microstrip feed lines. The coupled junction is utilized to connect the two BPFs to the antenna. This two band pass filters are designed and simulated to operate for the digital communication system (DCS) and Industrial Scientific and Medical (ISM) bands at 1.8 GHz and 2.45 GHz respectively. The proposed circuit presents good performances with an insertion loss lower than 2.3 dB and isolation between the two channels greater than 21 dB. The prototype of the optimized diplexer have been investigated numerically by using ADS Agilent and verified with CST microwave software.

Keywords: band pass filter, coupled junction, coupled stepped impedance resonators, diplexer, insertion loss, isolation

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5106 Investigation of the Evolutionary Equations of the Two-Planetary Problem of Three Bodies with Variable Masses

Authors: Zhanar Imanova

Abstract:

Masses of real celestial bodies change anisotropically and reactive forces appear, and they need to be taken into account in the study of these bodies' dynamics. We studied the two-planet problem of three bodies with variable masses in the presence of reactive forces and obtained the equations of perturbed motion in Newton’s form equations. The motion equations in the orbital coordinate system, unlike the Lagrange equation, are convenient for taking into account the reactive forces. The perturbing force is expanded in terms of osculating elements. The expansion of perturbing functions is a time-consuming analytical calculation and results in very cumber some analytical expressions. In the considered problem, we obtained expansions of perturbing functions by small parameters up to and including the second degree. In the non resonant case, we obtained evolution equations in the Newton equation form. All symbolic calculations were done in Wolfram Mathematica.

Keywords: two-planet, three-body problem, variable mass, evolutionary equations

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5105 Environmental and Economic Impact of Mangrove Deforestation: Case Study of Vadamaradchy East, Sri Lanka

Authors: Kumaraamy Sasikumar

Abstract:

The study was conducted in Vadamarachchi-East in Sri Lanka. Data collection was done for a period of two months from June to July 2011. The main focus of this study was to examine factors contributing to mangrove deforestation within the study area, and resultant impacts from deforestation. The study found that, the main factors that have contributed to deforestation include: Long civil wars in the region, poverty which pushed people to clear the forest to earn income through the sale of firewood and timber among others, industrial development, increasing demand for farm and settlement land, limited knowledge within the local community, weak government polices and implementation strategies, and natural disasters especially the 2004 Tsunami destruction. The impacts presented are those that impact both on the environment and the economy including; loss of income sources, loss of biodiversity, climate change, desertification, conflicts in the use of forest products and loss of land productivity due to reduced fertility caused by soil erosion. However, a few strategies have been put in place by the government to ensure the sustainable use of mangrove forest products, though these have not proved successful in reducing deforestation. The recommendations make suggestions to the government and other stakeholders to work together in ensuring sustainable use of natural resources, for example implementing laws and regulations aimed at controlling deforestation among others.

Keywords: deforestation, impacts, actors, environment, economic, sustainable development

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5104 Survey of Prevalence of Noise Induced Hearing Loss in Hawkers and Shopkeepers in Noisy Areas of Mumbai City

Authors: Hitesh Kshayap, Shantanu Arya, Ajay Basod, Sachin Sakhuja

Abstract:

This study was undertaken to measure the overall noise levels in different locations/zones and to estimate the prevalence of Noise induced hearing loss in Hawkers & Shopkeepers in Mumbai, India. The Hearing Test developed by American Academy Of Otolaryngology, translated from English to Hindi, and validated is used as a screening tool for hearing sensitivity was employed. The tool is having 14 items. Each item is scored on a scale 0, 1, 2 and 3. The score 6 and above indicated some difficulty or definite difficulty in hearing in daily activities and low score indicated lesser difficulty or normal hearing. The subjects who scored 6 or above or having tinnitus were made to undergo hearing evaluation by Pure tone audiometer. Further, the environmental noise levels were measured from Morning to Evening at road side at different Location/Hawking zones in Mumbai city using SLM9 Agronic 8928B & K type Digital Sound Level Meter) in dB (A). The maximum noise level of 100.0 dB (A) was recorded during evening hours from Chattrapati Shivaji Terminal to Colaba with overall noise level of 79.0 dB (A). However, the minimum noise level in this area was 72.6 dB (A) at any given point of time. Further, 54.6 dB (A) was recorded as minimum noise level during 8-9 am at Sion Circle. Further, commencement of flyovers with 2-tier traffic, sky walks, increasing number of vehicular traffic at road, high rise buildings and other commercial & urbanization activities in the Mumbai city most probably have resulted in increasing the overall environmental noise levels. Trees which acted as noise absorbers have been cut owing to rapid construction. The study involved 100 participants in the age range of 18 to 40 years of age, with the mean age of 29 years (S.D. =6.49). 46 participants having tinnitus or have obtained the score of 6 were made to undergo Pure Tone Audiometry and it was found that the prevalence rate of hearing loss in hawkers & shopkeepers is 19% (10% Hawkers and 9 % Shopkeepers). The results found indicates that 29 (42.6%) out of 64 Hawkers and 17 (47.2%) out of 36 Shopkeepers who underwent PTA had no significant difference in percentage of Noise Induced Hearing loss. The study results also reveal that participants who exhibited tinnitus 19 (41.30%) out of 46 were having mild to moderate sensorineural hearing loss between 3000Hz to 6000Hz. The Pure tone Audiogram pattern revealed Hearing loss at 4000 Hz and 6000 Hz while hearing at adjacent frequencies were nearly normal. 7 hawkers and 8 shopkeepers had mild notch while 3 hawkers and 1 shopkeeper had a moderate degree of notch. It is thus inferred that tinnitus is a strong indicator for presence of hearing loss and 4/6 KHz notch is a strong marker for road/traffic/ environmental noise as an occupational hazard for hawkers and shopkeepers. Mass awareness about these occupational hazards, regular hearing check up, early intervention along with sustainable development juxtaposed with social and urban forestry can help in this regard.

Keywords: NIHL, noise, sound level meter, tinnitus

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5103 Serum Levels of Plasminogen Activator Inhibitor-1 (PAI-1) Are Increased in Alzheimer’s Disease and MCI Patients and Correlate With Cognitive Deficits

Authors: Francesco Angelucci, Katerina Veverova, Alžbeta Katonová, Lydia Piendel, Martin Vyhnalek, Jakub Hort

Abstract:

Alzheimer's disease (AD) is a central nervous system (CNS) disease characterized by loss of memory, cognitive functions and neurodegeneration. Plasmin is an enzyme degrading many plasma proteins. In the CNS, plasmin may reduce the accumulation of A, and have other actions relevant to AD pathophysiology. Brain plasmin synthesis is regulated by two enzymes: one activating, the tissue plasminogen activator (tPA), and the other inhibiting, the plasminogen activator inhibitor-1 (PAI-1). We investigated whether tPA and PAI-1 serum levels in AD and amnestic mild cognitive impairment (aMCI) patients are altered compared to cognitively healthy controls. Moreover, we examined the PAI-1/tPA ratio in these patient groups. 40 AD, 40 aMCI and 10 healthy controls were recruited. Venous blood was collected and PAI-1 and tPA serum concentrations were quantified by sandwich ELISAs. The results showed that PAI-1 levels increased in AD and aMCI patients. This increase negatively correlated with cognitive deficit measured by MMSE. Similarly, the ratio between tPA and PAI-1 gradually increases in aMCI and AD patients. This study demonstrates that AD and aMCI patients have altered PAI-1 serum levels and PAI-1/tPA ratio. Since these enzymes are CNS regulators of plasmin, PAI-1 serum levels could be a marker reflecting a cognitive decline in AD.

Keywords: Alzheimer disease, amnestic mild cognitive impairment, plasmin, tissue-type plasminogen activator

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5102 Eye Diagram for a System of Highly Mode Coupled PMD/PDL Fiber

Authors: Suad M. Abuzariba, Liang Chen, Saeed Hadjifaradji

Abstract:

To evaluate the optical eye diagram due to polarization-mode dispersion (PMD), polarization-dependent loss (PDL), and chromatic dispersion (CD) for a system of highly mode coupled fiber with lumped section at any given optical pulse sequence we present an analytical modle. We found that with considering PDL and the polarization direction correlation between PMD and PDL, a system with highly mode coupled fiber with lumped section can have either higher or lower Q-factor than a highly mode coupled system with same root mean square PDL/PMD values. Also we noticed that a system of two highly mode coupled fibers connected together is not equivalent to a system of highly mode coupled fiber when fluctuation is considered

Keywords: polarization mode dispersion, polarization dependent loss, chromatic dispersion, optical eye diagram

Procedia PDF Downloads 855
5101 Numerical Simulation of the Kurtosis Effect on the EHL Problem

Authors: S. Gao, S. Srirattayawong

Abstract:

In this study, a computational fluid dynamics (CFD) model has been developed for studying the effect of surface roughness profile on the EHL problem. The cylinders contact geometry, meshing and calculation of the conservation of mass and momentum equations are carried out by using the commercial software packages ICEMCFD and ANSYS Fluent. The user defined functions (UDFs) for density, viscosity and elastic deformation of the cylinders as the functions of pressure and temperature have been defined for the CFD model. Three different surface roughness profiles are created and incorporated into the CFD model. It is found that the developed CFD model can predict the characteristics of fluid flow and heat transfer in the EHL problem, including the leading parameters such as the pressure distribution, minimal film thickness, viscosity, and density changes. The obtained results show that the pressure profile at the center of the contact area directly relates to the roughness amplitude. The rough surface with kurtosis value over 3 influences the fluctuated shape of pressure distribution higher than other cases.

Keywords: CFD, EHL, kurtosis, surface roughness

Procedia PDF Downloads 311
5100 Diffusion Mechanism of Aroma Compound (2-Acetyl-1-Pyrroline) in Rice During Storage

Authors: Mary Ann U. Baradi, Arnold R. Elepaño, Manuel Jose C. Regalado

Abstract:

Aromatic rice has become popular and continues to command higher price than ordinary rice because of its distinctive scent that makes it special. Freshly harvested aromatic rice exhibits strong aromatic scent but decreases with time and conditions during storage. Of the many volatile compounds in aromatic rice, 2-acetyl-1-pyrroline (2AP) is a major compound that gives rice its popcorn-like aroma. The diffusion mechanism of 2AP in rice was investigated. Semi-empirical models explaining 2AP diffusion as affected by temperature and duration were developed. Storage time and temperature affected 2AP loss via diffusion. The amount of 2AP in rice decreased with time. Free 2AP, being volatile, is lost due to diffusion. Storage experiment indicated rapid 2AP loss during the first five weeks and subsequently leveled off afterwards; attaining level of starch bound 2AP. Decline of 2AP during storage followed exponential equation and exhibited four stages; i.e. the initial, second, third and final stage. Free 2AP is easily lost while bound 2AP is left, only to be released upon exposure to high temperature such as cooking. Both free and bound 2AP is found in endosperm while free 2AP is in the bran. Around 63–67% of total 2AP was lost in brown and milled rice of MS 6 paddy kept at ambient. Samples stored at higher temperature (27°C) recorded higher 2AP loss than those kept at lower temperature (15°C). The study should be able to guide processors in understanding and controlling parameters in storage to produce high quality rice.

Keywords: 2-acetyl-1-pyrroline, aromatic rice, diffusion mechanism, storage

Procedia PDF Downloads 328
5099 Polyphosphate Kinase 1 Active Site Characterization for the Identification of Novel Antimicrobial Targets

Authors: Sanaa Bardaweel

Abstract:

Inorganic polyphosphate (poly P) is present in all living forms tested to date, from each of the three kingdoms of life. Studied mainly in prokaryotes, poly P and its associated enzymes are vital in diverse basic metabolism, in at least some structural functions and, notably, in stress responses. These plentiful and unrelated roles for poly P are probably the consequence of its presence in life-forms early in evolution. The genomes of many bacterial species, including pathogens, encode a homologue of a major poly P synthetic enzyme, poly P kinase 1 (PPK1). Genetic deletion of ppk1 results in reduced poly P levels and loss of pathogens virulence towards protozoa and animals. Thus far, no PPK1 homologue has been identified in higher-order eukaryotes and, therefore, PPK1 represents a novel target for chemotherapy. The idea of the current study is to purify the PPK1 from Escherichia coli to homogeneity in order to study the effect of active site point mutations on PPK1 catalysis via the application of site-directed mutagenesis strategy. The knowledge obtained about the active site of PPK1 will be utilized to characterize the catalytic and kinetic mechanism of PPK1 with model substrates. Comprehensive understanding of the enzyme kinetic mechanism and catalysis will be used to design and screen a library of synthetic compounds for potential discovery of selective PPK1-inhibitors.

Keywords: antimicobial, Escherichia coli, inorganic polyphosphate, PPK1-inhibitors

Procedia PDF Downloads 273
5098 Weight Loss and Symptom Improvement in Women with Secondary Lymphedema Using Semaglutide

Authors: Shivani Thakur, Jasmin Dominguez Cervantes, Ahmed Zabiba, Fatima Zabiba, Sandhini Agarwal, Kamalpreet Kaur, Hussein Maatouk, Shae Chand, Omar Madriz, Tiffany Huang, Saloni Bansal

Abstract:

The prevalence of lymphedema in women in rural communities highlights the importance of developing effective treatment and prevention methods. Subjects with secondary lymphedema in California’s Central Valley were surveyed at 6 surgical clinics to assess demographics and symptoms of lymphedema. Additionally, subjects on semaglutide treatment for obesity and/or T2DM were monitored for their diabetes management, weight loss progress, and lymphedema symptoms compared to subjects who were not treated with semaglutide. The subjects were followed for 12 months. Subjects who were treated with semaglutide completed pre-treatment questionnaires and follow-up post-treatment questionnaires at 3, 6, 9, 12 months, along with medical assessment. The untreated subjects completed similar questionnaires. The questionnaires investigated subjective feelings regarding lymphedema symptoms and management using a Likert-scale; quantitative leg measurements were collected, and blood work reviewed at these appointments. Paired difference t-tests, chi-squared tests, and independent sample t-tests were performed. 50 subjects, aged 18-75 years, completed the surveys evaluating secondary lymphedema: 90% female, 69% Hispanic, 45% Spanish speaking, 42% disabled, 57 % employed, 54% income range below 30 thousand dollars, and average BMI of 40. Both treatment and non-treatment groups noted the most common symptoms were leg swelling (x̄=3.2, ▁d= 1.3), leg pain (x̄=3.2, ▁d=1.6 ), loss of daily function (x̄=3, ▁d=1.4 ), and negative body image (x̄=4.4, ▁d=0.54). Subjects in the semaglutide treatment group >3 months of treatment compared to the untreated group demonstrated: 55% subject in the treated group had a 10% weight loss vs 3% in the untreated group (average BMI reduction by 11% vs untreated by 2.5%, p<0.05) and improved subjective feelings about their lymphedema symptoms: leg swelling (x̄=2.4, ▁d=0.45 vs x̄=3.2, ▁d=1.3, p<0.05), leg pain (x̄=2.2, ▁d=0.45 vs x̄= 3.2, ▁d= 1.6, p<0.05), and heaviness (x̄=2.2, ▁d=0.45 vs x̄=3, ▁d=1.56, p<0.05). Improvement in diabetes management was demonstrated by an average of 0.9 % decrease in A1C values compared to untreated 0.1 %, p<0.05. In comparison to untreated subjects, treatment subjects on semaglutide noted 6 cm decrease in the circumference of the leg, knee, calf, and ankle compared to 2 cm in untreated subjects, p<0.05. Semaglutide was shown to significantly improve weight loss, T2DM management, leg circumference, and secondary lymphedema functional, physical and psychosocial symptoms.

Keywords: diabetes, secondary lymphedema, semaglutide, obesity

Procedia PDF Downloads 50
5097 Tranexamic Acid in Orthopedic Surgery in Children

Authors: K. Amanzoui, A. Erragh, M. Elharit, A. Afif, K. Elfakhr, S. Kalouch, A. Chlilek

Abstract:

Orthopedic surgery is a provider of pre and postoperative bleeding; patients are exposed to several risks, and different measures are proposed to reduce bleeding during surgery, called the transfusion-sparing method, including tranexamic acid, which has shown its effectiveness in numerous studies. A prospective analytical study in 50 children was carried out in the orthopedic traumatology operating room of the EL HAROUCHI hospital of the CHU IBN ROCHD in Casablanca over a period of six months (April to October 2022). Two groups were randomized: one receiving tranexamic acid (Group A) and a non-receiving control group (Group B). The average age was 10.3 years, of which 58.8% were female. The first type of surgery was thoracolumbar scoliosis (52%). The average preoperative hemoglobin was 12.28 g/dl in group A, against 12.67 g/dl in the control group. There was no significant difference between the two groups (p=0.148). Mean intraoperative bleeding was 396.29 ml in group A versus 412 ml in the control group. No significant difference was observed for this parameter (p=0.632). The average hemoglobin level in the immediate postoperative period in our patients is 10.2 g/dl. In group A, it was 10.95 g/dl versus 10.93 g/dl in group B. At H24 postoperative, the mean hemoglobin value was 10.29 g/dl in group A against 9.5 g/dl in group B. For group A, the blood loss recorded during the first 24 hours was 209.43 ml, against 372 ml in group B, with a significant difference between the two groups (p=0.001). There is no statistically significant difference between the 2 groups in terms of the use of fillers, ephedrine or intraoperative transfusion. While for postoperative transfusion, we note the existence of a statistically significant difference between group A and group B. It is suggested that the use of tranexamic acid is an effective, simple, and low-cost way to limit postoperative blood loss and the need for transfusion.

Keywords: tranexamic acid, blood loss, orthopedic surgery, children

Procedia PDF Downloads 60
5096 Adopting Collaborative Business Processes to Prevent the Loss of Information in Public Administration Organisations

Authors: A. Capodieci, G. Del Fiore, L. Mainetti

Abstract:

Recently, the use of web 2.0 tools has increased in companies and public administration organizations. This phenomenon, known as "Enterprise 2.0", has, de facto, modified common organizational and operative practices. This has led “knowledge workers” to change their working practices through the use of Web 2.0 communication tools. Unfortunately, these tools have not been integrated with existing enterprise information systems, a situation that could potentially lead to a loss of information. This is an important problem in an organizational context, because knowledge of information exchanged within the organization is needed to increase the efficiency and competitiveness of the organization. In this article we demonstrate that it is possible to capture this knowledge using collaboration processes, which are processes of abstraction created in accordance with design patterns and applied to new organizational operative practices.

Keywords: business practices, business process patterns, collaboration tools, enterprise 2.0, knowledge workers

Procedia PDF Downloads 349
5095 Interoception and Its Role in Connecting Empathy, Bodily Perception and Conceptual Representations: A Cross-Cultural Online Study

Authors: Fabio Marson, Revital Naor-Ziv, Patrizio Paoletti, Joseph Glicksohn, Filippo Carducci, Tal Dotan Ben-Soussan

Abstract:

According to embodied cognition theories, higher-order cognitive functions and complex behaviors seems to be affected by bodily states. For example, the polyvagal theory suggests that the human autonomic nervous system evolved to support social interactions. Accordingly, integration and perception of information related to the physiological state arising from the peripherical nervous system (i.e., interoception) play a role in the regulation of social interaction by modulating emotional responses and prosocial behaviors. Moreover, recent studies showed that interoception is involved in the representations of conceptual knowledge, suggesting that the bodily information carried by the interoceptive system provides a perceptual basis for the embodiment of abstract concepts, especially those related to social and emotional domains. However, to the best of our knowledge, no studies explored the relationship between interoception, prosocial behaviors, and conceptual representations. Considering the privileged position of interoception in mediating higher-order cognition and social interaction, we designed a cross-cultural study to explore the relationship between interoception, the sensitivity of bodily functions, and empathy. We recruited Italian, English, and Hebrew participants, and we asked them to fill in a questionnaire about empathy (Empathy Quotient), a questionnaire about bodily perception (Body Perception Questionnaire), and to rate different concrete and abstract concepts for the extent such concepts can be experienced through vision, hearing, taste, smell, touch, and interoception. We observed that in all languages, interoception ratings for abstract concepts were greater than for concrete concepts. Importantly, interoception ratings for abstract concepts were positively correlated with empathy and sensitivity of bodily functions. Our results suggest that participants with higher empathy and sensitivity of bodily functions show also a greater embodiment of abstract concepts in interoception, providing further evidence for the importance of the interoceptive system in regulating prosocial behaviors and integrating conceptual representations.

Keywords: conceptual representations, embodiment, empathy, empathy quotient, interoception, prosocial behaviors

Procedia PDF Downloads 140
5094 The MTHFR C677T Polymorphism Screening: A Challenge in Recurrent Pregnancy Loss

Authors: Rim Frikha, Nouha Bouayed, Afifa Sellami, Nozha Chakroun, Salima Daoud, Leila Keskes, Tarek Rebai

Abstract:

Introduction: Recurrent pregnancy loss (RPL) defined as two or more pregnancy losses, is a serious clinical problem. Methylene-tetrahydro-folate-reductase (MTHFR) polymorphisms, commonly the variant C677T is recognized as an inherited thrombophilia which might affect embryonic development and pregnancy success and cause pregnancy complications as RPL. Material and Methods DNA was extracted from peripheral blood samples and PCR-RFLP was performed for the molecular diagnosis of the C677T MTHFR polymorphism among 70 patients (35 couples) with more than 2 fetal losses. Aims and Objective: The aim of this study is to determine the frequency of MTHFR C677T among Tunisian couples with RPL and to critically analyze the available literature on the importance of MTHFR polymorphism testing in the management of RPL. Result and comments: No C677T mutation was detected in the carriers of RPL. This result would be related to sample size and to different criteria (number of abortion), - The association between MTHFR polymorphisms and pregnancy complications has been reported but with controversial results. - A lack of evidence for MTHFR polymorphism testing previously recommended by ACMG (American College of Medical medicine). Our study highlights the importance of screening of MTHFR polymorphism since the real impact of such thrombotic molecular defect on the pregnancy outcome is evident. - Folic supplementation of these patients during pregnancy can prevent such complications and lead to a successful pregnancy outcome.

Keywords: methylenetetrahydrofolate reductase, C677T, recurrent pregnancy loss, genetic testing

Procedia PDF Downloads 297