Search results for: boundary control
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 11936

Search results for: boundary control

8996 Optimal Placement of the Unified Power Controller to Improve the Power System Restoration

Authors: Mohammad Reza Esmaili

Abstract:

One of the most important parts of the restoration process of a power network is the synchronizing of its subsystems. In this situation, the biggest concern of the system operators will be the reduction of the standing phase angle (SPA) between the endpoints of the two islands. In this regard, the system operators perform various actions and maneuvers so that the synchronization operation of the subsystems is successfully carried out and the system finally reaches acceptable stability. The most common of these actions include load control, generation control and, in some cases, changing the network topology. Although these maneuvers are simple and common, due to the weak network and extreme load changes, the restoration will be associated with low speed. One of the best ways to control the SPA is to use FACTS devices. By applying a soft control signal, these tools can reduce the SPA between two subsystems with more speed and accuracy, and the synchronization process can be done in less time. Meanwhile, the unified power controller (UPFC), a series-parallel compensator device with the change of transmission line power and proper adjustment of the phase angle, will be the proposed option in order to realize the subject of this research. Therefore, with the optimal placement of UPFC in a power system, in addition to improving the normal conditions of the system, it is expected to be effective in reducing the SPA during power system restoration. Therefore, the presented paper provides an optimal structure to coordinate the three problems of improving the division of subsystems, reducing the SPA and optimal power flow with the aim of determining the optimal location of UPFC and optimal subsystems. The proposed objective functions in this paper include maximizing the quality of the subsystems, reducing the SPA at the endpoints of the subsystems, and reducing the losses of the power system. Since there will be a possibility of creating contradictions in the simultaneous optimization of the proposed objective functions, the structure of the proposed optimization problem is introduced as a non-linear multi-objective problem, and the Pareto optimization method is used to solve it. The innovative technique proposed to implement the optimization process of the mentioned problem is an optimization algorithm called the water cycle (WCA). To evaluate the proposed method, the IEEE 39 bus power system will be used.

Keywords: UPFC, SPA, water cycle algorithm, multi-objective problem, pareto

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8995 Generalization of Clustering Coefficient on Lattice Networks Applied to Criminal Networks

Authors: Christian H. Sanabria-Montaña, Rodrigo Huerta-Quintanilla

Abstract:

A lattice network is a special type of network in which all nodes have the same number of links, and its boundary conditions are periodic. The most basic lattice network is the ring, a one-dimensional network with periodic border conditions. In contrast, the Cartesian product of d rings forms a d-dimensional lattice network. An analytical expression currently exists for the clustering coefficient in this type of network, but the theoretical value is valid only up to certain connectivity value; in other words, the analytical expression is incomplete. Here we obtain analytically the clustering coefficient expression in d-dimensional lattice networks for any link density. Our analytical results show that the clustering coefficient for a lattice network with density of links that tend to 1, leads to the value of the clustering coefficient of a fully connected network. We developed a model on criminology in which the generalized clustering coefficient expression is applied. The model states that delinquents learn the know-how of crime business by sharing knowledge, directly or indirectly, with their friends of the gang. This generalization shed light on the network properties, which is important to develop new models in different fields where network structure plays an important role in the system dynamic, such as criminology, evolutionary game theory, econophysics, among others.

Keywords: clustering coefficient, criminology, generalized, regular network d-dimensional

Procedia PDF Downloads 411
8994 Authentic Engagement for Institutional Leadership: Implications for Educational Policy and Planning

Authors: Simeon Adebayo Oladipo

Abstract:

Institutional administrators are currently facing pressure and challenges in their daily operations. Reasons for this may include the increasing multiplicity, uncertainty and tension that permeate institutional leadership. Authentic engagement for institutional leadership is premised on the ethical foundation that the leaders in the schools are engaged. The institutional effectiveness is dependent on the relationship that exists between the leaders and employees in the workplace. Leader’s self-awareness, relational transparency, emotional control, strong moral code and accountability have a positive influence on authentic engagement which variably determines leadership effectiveness. This study therefore examined the role of authentic engagement in effective school leadership; explored the interrelationship of authentic engagement indices in school leadership. The study adopted the descriptive research of the survey type using a quantitative method to gather data through a questionnaire among school leaders in Lagos State Tertiary Institutions. The population for the study consisted of all Heads of Departments, Deans and Principal Officers in Lagos State Tertiary Institutions. A sample size of 255 Heads of Departments, Deans and Principal Officers participated in the study. The data gathered were analyzed using descriptive and inferential statistical tools. The findings indicated that authentic engagement plays a crucial role in increasing leadership effectiveness amongst Heads of Departments, Deans and Principal Officers. The study recommended among others that there is a need for effective measures to enhance authentic engagement of institutional leadership practices through relevant educational support systems and effective quality control.

Keywords: authentic engagement, self-awareness, relational transparency, emotional control

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8993 Functional Mortality of Anopheles stephensi, the Urban Malaria Vector as Induced by the Sublethal Exposure to Deltamethrin

Authors: P. Aarumugam, N. Krishnamoorthy, K. Gunasekaran

Abstract:

The mosquitoes with loss of minimum three legs especially the hind legs have the negative impact on the survival hood of mosquitoes. Three days old unfed adult female laboratory strain was selected in each generation against sublethal dosages (0.004%, 0.005%, 0.007% and 0.01%) of deltamethrin upto 40 generations. Impregnated papers with acetone were used for control. Every fourth generation, survived mosquitoes were observed for functional mortality. Hind legs lost were significantly (P< 0.05) higher in treated than the controls up to generation 24, thereafter no significant lost. In contrary, no significant forelegs lost among exposed mosquitoes. Middle legs lost were also not significant in the exposed mosquitoes except first generation (F1). The field strain (Chennai) did not show any significant loss of legs (fore or mid or hind) compared to the control. The selection pressure on mosquito population influences strong natural selection to develop various adaptive mechanisms.

Keywords: Anopheles stephensi, deltamethrin, functional mortality, synthetic pyrethroids

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8992 FZP Design Considering Spherical Wave Incidence

Authors: Sergio Pérez-López, Daniel Tarrazó-Serrano, José M. Fuster, Pilar Candelas, Constanza Rubio

Abstract:

Fresnel Zone Plates (FZPs) are widely used in many areas, such as optics, microwaves or acoustics. On the design of FZPs, plane wave incidence is typically considered, but that is not usually the case in ultrasounds, especially in applications where a piston emitter is placed at a certain distance from the lens. In these cases, having control of the focal distance is very important, and with the usual Fresnel equation a focal displacement from the theoretical distance is observed due to the plane wave supposition. In this work, a comparison between FZP with plane wave incidence design and FZP with point source design in the case of piston emitter is presented. Influence of the main parameters of the piston in the final focalization profile has been studied. Numerical models and experimental results are shown, and they prove that when spherical wave incidence is considered for the piston case, it is possible to have a fine control of the focal distance in comparison with the classical design method.

Keywords: focusing, Fresnel zone plates, FZP, ultrasound

Procedia PDF Downloads 248
8991 Influence of Salicylic Acid on Submergence Stress Recovery in Selected Rice Cultivars (Oryza sativa L.)

Authors: Ja’afar U., A. M. Gumi, Salisu N., Obadiah C. D.

Abstract:

Rice is susceptible to flooding due to its semi-aquatic characteristics, which enable it to thrive in wet or submerged environments. The development of aerenchyma allows for oxygen transfer, enabling faster lengthening of submerged shoot organs. Rice's germination and early seedling growth phases are highly intolerant of submersion, resulting in survival in low-oxygen environments. The research involved a study on rice plants treated with salicylic acid at different concentrations. Hypo was used for washing, while a reagent was used for submergence treatment. The plants were waterlogged for 11 days and submerged for 7 days, with control plants receiving distilled water. The study found a significant difference between Jirani Zawara's control and treated plants, with plants treated with 2 g/L of S.A. showing a 6.00 node increase per plant and Faro cultivars having more nodes. The study found significant differences between the control and treated plants, with the Jirani Zawara plant showing longer internode lengths and the Faro cultivar having longer internode lengths, while the B.G. cultivar had the longest. The research found that the Jirani Zawara cultivar treated with 3 g/L of S.A. produced tallest plants, with heights increasing from 14.43 cm to 15.50 cm in Faro cultivar S.A., and the highest height was 16.30 cm. The study reveals that salicylic acid significantly enhances the number of nodes, internode length, plant height, and root length in rice cultivars, thereby improving submerged stress recovery and promoting plant development.

Keywords: rice, submergence, stress, salicylic acid

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8990 The Use of Metformin in Treatment of Polycystic Ovary Syndrome (PCOS) and Glucose Control in Pregnant Women with Gestational Diabetes Mellitus (GDM) at Tripoli Medical Center

Authors: Ebtisam A. Benomran, Abdurrauf M. Gusbi, Malak S. Elazarg, M. Sultan, Layla M. Kafu, Arwa M. Matoug, Esra E. Benamara

Abstract:

Normal pregnancy is associated with metabolic changes leading to decreased insulin sensitivity and reduced glucose tolerance, however, 3-5% of pregnant women proceed to develop gestational diabetes mellitus (GDM). Researcher studied the use of metformin in many fields and the benefit to risk balance of using metformin during pregnancy and the risk of fetotoxic. In this study we examined the use of Metformin to control Glucose in pregnant Women with gestational diabetes mellitus (GDM) and evaluate its safety use during the first trimester of pregnancy.A group of pregnant patients with gestational diabetes mellitus from the first trimester of pregnancy, non smoking with no family history of congenital malformation disease, aged between (20-45 years) and have no liver diseases and who had indicating good compliance at more than one visit over several month until delivery put on Metformin were participated in this trial. Our study shown that all the studied group of pregnant women using metformin 500 mg daily delivered a healthy babies. Meta-analysis by mother risk program showed no increase in incidence of malformations by use Metformin during the first trimester of pregnancy. A hundred outpatients were participated in the survey on the general knowledge and awareness of diabetic patients to their illness and medication used their aged between 20-40 years old. In this survey we realize that 90% of the doctors are not giving the patient full information about their illness and the use of metformin during pregnancy, also about 65% of the patients did not know about the nutritionist in the hospital and the right control diet for diabetes. Courses on first aid, rapid diagnosis of poisoning and follow the written procedures to dealing with such cases.

Keywords: gestational diabetes, malformations, metformin, pregnancy

Procedia PDF Downloads 489
8989 Remote Electroacupuncture Analgesia at Contralateral LI4 Acupoint in Complete Freund's Adjuvant-Induced Inflammatory Hindpaw Pain

Authors: Tong-Chien Wu, Ching-Liang Hsieh, Yi-Wen Lin

Abstract:

There are accumulating evidences surrounding the therapeutic effect of electroacupuncture (EA). Local EA can reliably attenuate inflammatory pain in mouse with unclear mechanisms. However, the effect of EA on distal and contralateral acupoint for pain control has been rarely studied and the result was controversial. Here in our study, we found that inflammatory hindpaw pain in mouth, which was induced by injecting the complete Freund’s adjuvant (CFA) 2 days ago can be alleviated immediately after 2Hz 15mins EA treatment at contralateral forefoot acupoint LI4 through both mechanic and thermal behavior test, while sham acupoint group is not. The efficacy was observed to be more obvious after the second round of EA treatment on the following day. This analgesic effect is produced by applying EA to a site remote from the painful area. The present study provides a powerful experimental animal model that can be used for investigating the unique physiological mechanisms involved in acupuncture analgesia.

Keywords: remote electroacupuncture, distal EA, pain control, anti-inflammation

Procedia PDF Downloads 184
8988 The Rayleigh Quotient for Structural Element Vibration Analysis with Finite Element Method

Authors: Falek Kamel

Abstract:

Various approaches are usually used in the dynamic analysis of beams vibrating transversally. For this, numerical methods allowing the solving of the general eigenvalue problem are utilized. The equilibrium equations describe the movement resulting from the solution of a fourth-order differential equation. Our investigation is based on the finite element method. The findings of these investigations are the vibration frequencies obtained by the Jacobi method. Two types of the elementary mass matrix are considered, representing a uniform distribution of the mass along with the element and concentrated ones located at fixed points whose number is increased progressively separated by equal distances at each evaluation stage. The studied beams have different boundary constraints representing several classical situations. Comparisons are made for beams where the distributed mass is replaced by n concentrated masses. As expected, the first calculus stage is to obtain the lowest number of beam parts that gives a frequency comparable to that issued from the Rayleigh formula. The obtained values are then compared to theoretical results based on the assumptions of the Bernoulli-Euler theory. These steps are used for the second type of mass representation in the same manner.

Keywords: structural elements, beams vibrating, dynamic analysis, finite element method, Jacobi method

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8987 A Technique for Image Segmentation Using K-Means Clustering Classification

Authors: Sadia Basar, Naila Habib, Awais Adnan

Abstract:

The paper presents the Technique for Image Segmentation Using K-Means Clustering Classification. The presented algorithms were specific, however, missed the neighboring information and required high-speed computerized machines to run the segmentation algorithms. Clustering is the process of partitioning a group of data points into a small number of clusters. The proposed method is content-aware and feature extraction method which is able to run on low-end computerized machines, simple algorithm, required low-quality streaming, efficient and used for security purpose. It has the capability to highlight the boundary and the object. At first, the user enters the data in the representation of the input. Then in the next step, the digital image is converted into groups clusters. Clusters are divided into many regions. The same categories with same features of clusters are assembled within a group and different clusters are placed in other groups. Finally, the clusters are combined with respect to similar features and then represented in the form of segments. The clustered image depicts the clear representation of the digital image in order to highlight the regions and boundaries of the image. At last, the final image is presented in the form of segments. All colors of the image are separated in clusters.

Keywords: clustering, image segmentation, K-means function, local and global minimum, region

Procedia PDF Downloads 371
8986 Surface Sterilization of Aquatic Plant, Cryptopcoryne affinis by Using Clorox and Mercury Chloride

Authors: Sridevi Devadas

Abstract:

This study was aimed to examine the combination efficiency of Clorox (5.25% Sodium Hypochlorite) and mercury chloride (HgCl2) as reagent for surface sterilization process of aquatic plant, Cryptocoryne affinis (C. affinis). The treatment applied 10% of the Clorox and 0.1 ppm of mercury chloride. The maximum exposure time for Clorox and mercury chloride was 10 min and 60 sec respectively. After exposed to the treatments protocols (T1-T15) the explants were transferred to culture room under control temperature at 25°C ± 2°C and subjected to 16 hours fluorescence light (2000 lumens) for 30 days. The both sterilizing agents were not applied on control specimens. Upon analysis, the result indicates all of the treatments protocols produced sterile explants at range of minimum 1.5 ± 0.7 (30%) to maximum 5.0 ± 0.0 (100%). Meanwhile, maximum 1.0 ± 0.7 numbers of leaves and 1.4 ± 0.6 numbers of roots have been produced. The optimized exposure time was 0 to 15 min for Clorox and 30 sec for HgCl2 whereby 90% to 100% sterilization was archived at this condition.

Keywords: Cryptocoryne affinis, surface sterilization, tissue culture, clorox, mercury chloride

Procedia PDF Downloads 599
8985 Preparation and Size Control of Sub-100 Nm Pure Nanodrugs

Authors: Jinfeng Zhang, Chun-Sing Lee

Abstract:

Pure nanodrugs (PNDs) – nanoparticles consisting entirely of drug molecules, have been considered as promising candidates for the next-generation nanodrugs. However, the traditional preparation method via reprecipitation faces critical challenges including low production rates, relatively large particle sizes and batch-to-batch variations. Here, for the first time, we successfully developed a novel, versatile and controllable strategy for preparing PNDs via an anodized aluminium oxide (AAO) template-assisted method. With this approach, we prepared PNDs of an anti-cancer drug (VM-26) with precisely controlled sizes reaching the sub-20 nm range. This template-assisted approach has much higher feasibility for mass production comparing to the conventional reprecipitation method and is beneficial for future clinical translation. The present method is further demonstrated to be easily applicable for a wide range of hydrophobic biomolecules without the need of custom molecular modifications and can be extended for preparing all-in-one nanostructures with different functional agents.

Keywords: drug delivery, pure nanodrugs, size control, template

Procedia PDF Downloads 305
8984 Domestic and Foreign Terrorism: Evaluation of the Breeding Ground

Authors: T. K. Hung

Abstract:

Terrorism acts have occurred across both developed and developing states, with well-identified motivation and causes. For many years, terrorism eradication has become a major topic yet only passive actions were taken in response to acts. The linkage between the location of terrorism occurrence and breeding ground is not well-documented, resulting in the passive approach used in counter-terrorism nowadays. The evaluation investigates all post-9/11 terrorism affairs considering their state capacity, safety, ease of border access control, religion diversity, and technology access, to measure the level of breeding ground of the states. Those "weak" states with poor border access control, resources capacity and domestic safety are the best breeding ground for terrorists. Although many attacks were caused by religious motivation, religion diversity does not predict the breeding ground. States with censored technology access, particular computer-mediated communication, predict on the terrorism breeding ground, moderated by the level of breeding ground of neighboring states.

Keywords: counter-terrorism, lethality, security, terrorism

Procedia PDF Downloads 337
8983 A Review of HVDC Modular Multilevel Converters Subjected to DC and AC Faults

Authors: Jude Inwumoh, Adam P. R. Taylor, Kosala Gunawardane

Abstract:

Modular multilevel converters (MMC) exhibit a highly scalable and modular characteristic with good voltage/power expansion, fault tolerance capability, low output harmonic content, good redundancy, and a flexible front-end configuration. Fault detection, location, and isolation, as well as maintaining fault ride-through (FRT), are major challenges to MMC reliability and power supply sustainability. Different papers have been reviewed to seek the best MMC configuration with fault capability. DC faults are the most common fault, while the probability that AC fault occurs in a modular multilevel converter (MCC) is low; though, AC faults consequence are severe. This paper reviews several MMC topologies and modulation techniques in tackling faults. These fault control strategies are compared based on cost, complexity, controllability, and power loss. A meshed network of half-bridge (HB) MMC topology was optimal in rendering fault ride through than any other MMC topologies but only when combined with DC circuit breakers (CBS), AC CBS, and fault current limiters (FCL).

Keywords: MMC-HVDC, DC faults, fault current limiters, control scheme

Procedia PDF Downloads 137
8982 The Influence of Aerobic Physical Exercise with Different Frequency to Concentration of Vascular Endothelial Growth Factor in Brain Tissue of Wistar Rat

Authors: Rostika Flora, Muhammad Zulkarnain, Syokumawena

Abstract:

Background: Aerobic physical exercises are recommended to keep body fit and healthy although physical exercises themselves can increase body metabolism and oxygen and can lead into tissue hypoxia. Oxygen pressure can serve as Vascular Endhothelial Growth Factor (VEGF) regulator. Hypoxia increases gene expression of VEGF through ascendant regulation of HIF-1. VEGF is involved in regulating angiogenesis process. Aerobic physical exercises can increase the concentration of VEGF in brain and enables angiogenesis process. We have investigated the influence of aerobic physical exercise to the VGEF concentration of wistar rat’s brain. Methods: This was experimental study using post test only control group design. Independent t-test was used as statistical test. The samples were twenty four wistar rat (Rattus Norvegicus) which were divided into four groups: group P1 (control group), group P2 (treatment group with once-a-week exercise), group P3 (treatment group with three time-a-week exercise), and group P4 (treatment group with seven time-a-week exercise). Group P2, P3, and P4 were treated with treadmil with speed of 20 m/minute for 30 minutes. The concentration of VEGF was determined by ELISA. Results: There was a significant increase of VEGF in treatment group compared with control one (<0.05). The maximum increase was found in group P2 (129.02±64.49) and the minimum increase was in group P4 (96.98±11.20). Conclusion: The frequency of aerobic physical exercises influenced the concentration of Vascular Endhothelial Growth Factor (VEGF) of brain tissue of Rattus Norvegicus.

Keywords: brain tissue, hypoxia, physical exercises, vascular endhothelial growth factor

Procedia PDF Downloads 490
8981 The Preventive Effect of Metformin on Paclitaxel-Induced Peripheral Neuropathy

Authors: AliAkbar Hafezi, Jamshid Abedi, Jalal Taherian, Behnam Kadkhodaei, Mahsa Elahi

Abstract:

Background. Peripheral neuropathy is a common side effect of the administration of neurotoxic chemotherapy agents. This adverse effect is a major dose-limiting factor of many commonly used chemotherapy drugs. Currently, there are no Food and Drug Administration (FDA) approved medications for the prevention or treatment of chemotherapy-induced peripheral neuropathy. Therefore, this study was performed to investigate the efficacy and safety of metformin on paclitaxel-induced peripheral neuropathy (PIPN). Methods. In this randomized clinical trial, cancer patients who were candidates for chemotherapy with paclitaxel referred to the radiation oncology departments in Iran from 2022 to 2023 were studied. Patients were randomly divided into two groups; 1- Case group (n = 30) received metformin 500 mg orally twice a day after meals during chemotherapy with paclitaxel, and 2- Control group (30 people) received chemotherapy without metformin or any additional medication. Patients were visited in terms of numbness or other neurological symptoms two weeks before chemotherapy, 1-2 days before and weekly during chemotherapy, and at the end of the study. They were assessed by nerve conduction study (NCS) before intervention and one week after the end of chemotherapy. The primary outcome was the efficacy in reducing PIPN and the secondary outcome was adverse effects. Eventually, the outcomes were compared between the two groups of patients. Results. A total of 60 female cancer patients receiving chemotherapy with paclitaxel were evaluated in two groups. The groups were matched in terms of age, body mass index, fasting blood sugar, smoking, pathologic stage, and creatinine levels. The results showed that 18 patients (60.0 %) in the case group and 23 patients (76.6 %) in the control group had PIPN clinically (P = 0.267), and NCS showed 11 patients (36.6 %) in the case group and 15 patients (50.0 %) in the control group suffered from PIPN which no significant difference was observed between the two groups (P = 0.435). Diarrhea (n = 3; 10.0 %) and nausea (n = 3; 10.0 %) were the most common side effects of metformin in the case group and no serious side effects (lactic acidosis and anemia) were found in these patients. Conclusion. This study indicated that metformin did not significantly prevent PIPN in cancer patients receiving chemotherapy, although the frequency of peripheral neuropathy in the case group was lower than in the control group. The use of metformin in the patients had acceptable safety and no serious side effects were reported.

Keywords: peripheral neuropathy, chemotherapy, paclitaxel, metformin

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8980 Systolic Blood Pressure Responses to Aerobic Exercise among HIV Positive Patients

Authors: Ka'abu Mu'azu

Abstract:

The study examines the effect of varied intensities of aerobic exercise on Systolic Blood Pressure (SBP) among HIV/AIDS positive patients. Participants of mean age of 20.4 years were randomized into four groups. High Intensity Group (HIG), Moderate Intensity Group (MIG), Low Intensity Group (LIG) and Control Group (COG). SBP was measured at baseline (pre-exercise) and post-exercise (8 weeks). Analysis of variance (ANOVA) indicates a significant training effect on resting values of SBP (F [3, 15] = 8.9, P < 0.05). Sheffe post hoc analysis indicated that both HIG and MIG significantly differ from control (P < 0.05). Dependent t- test indicates difference in HIG (t [7] = 6.5, P < 0.05) and slightly in MIG (t [7] = 5.4, P < 0.05). The study concluded that aerobic exercise is effective in reducing resting values of SBP particularly the activities that are high intensity in nature. The study recommends that high and moderate intensity aerobic exercise should be used for improving health condition of HIV/AIDS patients as regard to decrease in resting value of SBP.

Keywords: systolic blood pressure, aerobic exercise, HIV patients, health sciences

Procedia PDF Downloads 378
8979 Quality Assurance as an Educational Development Tool: Case from the European Higher Education

Authors: Maha Mourad

Abstract:

Higher education in any competitive European economy should serve the new information society by increasing the supply of good quality education services and by creating good international brands in the international higher education market. Hence, continuous risk management techniques through higher educational reforms programs became one of the top priorities within the European Union to control the quality of higher education. Risk is higher education is studies by several researchers who agreed that the risk in higher education has a direct influence on continuity of quality education and research contribution. The focus of this research is to highlights the Internal Quality Assurance (IQA) activities in the Polish higher education system as a risk management tool used to control the quality of education. This paper presents a qualitative empirical analysis in 5 different universities in Poland. In addition, it aims to help in finding global practical and create benchmark for policy makers concerning the risk management techniques based on the Polish experience.

Keywords: education development, quality assurance, sustainability, european higher education

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8978 Optimal Design of Composite Cylindrical Shell Based on Nonlinear Finite Element Analysis

Authors: Haider M. Alsaeq

Abstract:

The present research is an attempt to figure out the best configuration of composite cylindrical shells of the sandwich type, i.e. the lightest design of such shells required to sustain a certain load over a certain area. The optimization is based on elastic-plastic geometrically nonlinear incremental-iterative finite element analysis. The nine-node degenerated curved shell element is used in which five degrees of freedom are specified at each nodal point, with a layered model. The formulation of the geometrical nonlinearity problem is carried out using the well-known total Lagrangian principle. For the structural optimization problem, which is dealt with as a constrained nonlinear optimization, the so-called Modified Hooke and Jeeves method is employed by considering the weight of the shell as the objective function with stress and geometrical constraints. It was concluded that the optimum design of composite sandwich cylindrical shell that have a rigid polyurethane foam core and steel facing occurs when the area covered by the shell becomes almost square with a ratio of core thickness to facing thickness lies between 45 and 49, while the optimum height to length ration varies from 0.03 to 0.08 depending on the aspect ratio of the shell and its boundary conditions.

Keywords: composite structure, cylindrical shell, optimization, non-linear analysis, finite element

Procedia PDF Downloads 390
8977 Sympathetic Skin Response and Reaction Times in Chronic Autoimmune Thyroiditis; An Overlooked Electrodiagnostic Study

Authors: Oya Umit Yemisci, Nur Saracgil Cosar, Tubanur Ozturk Sisman, Selin Ozen

Abstract:

Chronic autoimmune thyroiditis (AIT) may result in a wide spectrum of reversible abnormalities in the neuromuscular function. Usually, proximal muscle-related symptoms and neuropathic findings such as mild axonal peripheral neuropathy have been reported. Sympathetic skin responses are useful in evaluating sudomotor activity of the unmyelinated sympathetic fibers of the autonomic nervous system. Neurocognitive impairment may also be a prominent feature of hypothyroidism, particularly in elderly patients. Electromyographic reaction times as a highly sensitive parameter provides. Objective data concerning cognitive and motor functions. The aim of this study was to evaluate peripheral nerve functions, sympathetic skin response and electroneuromyographic (ENMG) reaction times in euthyroid and subclinically hypothyroid patients with a diagnosis of AIT and compare to those of a control group. Thirty-five euthyroid, 19 patients with subclinical hypothyroidism and 35 age and sex-matched healthy subjects were included in the study. Motor and sensory nerve conduction studies, sympathetic skin responses recorded from hand and foot by stimulating contralateral median nerve and simple reaction times by stimulating tibial nerve and recording from extensor indicis proprius muscle were performed to all patients and control group. Only median nerve sensory conduction velocities of the forearm were slower in patients with AIT compared to the control group (p=0.019). Otherwise, nerve conduction studies and sympathetic skin responses showed no significant difference between the patients and the control group. However, reaction times were shorter in the healthy subjects compared to AIT patients. Prolongation in the reaction times may be considered as a parameter reflecting the alterations in the cognitive functions related to the primary disease process in AIT. Combining sympathetic skin responses with more quantitative tests such as cardiovascular tests and sudomotor axon reflex testing may allow us to determine higher rates of involvement of the autonomic nervous system in AIT.

Keywords: sympathetic skin response, simple reaction time, chronic autoimmune thyroiditis

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8976 Unsteady Natural Convection in a Square Cavity Partially Filled with Porous Media Using a Thermal Non-Equilibrium Model

Authors: Ammar Alsabery, Habibis Saleh, Norazam Arbin, Ishak Hashim

Abstract:

Unsteady natural convection and heat transfer in a square cavity partially filled with porous media using a thermal non-equilibrium model is studied in this paper. The left vertical wall is maintained at a constant hot temperature and the right vertical wall is maintained at a constant cold temperature, while the horizontal walls are adiabatic. The governing equations are obtained by applying the Darcy model and Boussinesq approximation. COMSOL's finite element method is used to solve the non-dimensional governing equations together with specified boundary conditions. The governing parameters of this study are the Rayleigh number, the modified thermal conductivity ratio, the inter-phase heat transfer coefficien and the time independent. The results presented for values of the governing parameters in terms of streamlines in both fluid/porous layer, isotherms of fluid and solid porous layer, isotherms of fluid layer, and average Nusselt number.

Keywords: unsteady natural convection, thermal non-equilibrium model, Darcy model

Procedia PDF Downloads 375
8975 Biosensors as Analytical Tools in Legume Processing

Authors: S. V. Ncube, A. I. O. Jideani, E. T. Gwata

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The plight of food insecurity in developing countries has led to renewed interest in underutilized legumes. Their nutritional versatility, desirable functionality, pharmaceutical value and inherent bioactive compounds have drawn the attention of researchers. This has provoked the development of value added products with the aim of commercially exploiting their full potential. However processing of these legumes leads to changes in nutritional composition as affected by processing variables like pH, temperature and pressure. There is therefore a need for process control and quality assurance during production of the value added products. However, conventional methods for microbiological and biochemical identification are labour intensive and time-consuming. Biosensors offer rapid and affordable methods to assure the quality of the products. They may be used to quantify nutrients and anti-nutrients in the products while manipulating and monitoring variables such as pH, temperature, pressure and oxygen that affect the quality of the final product. This review gives an overview of the types of biosensors used in the food industry, their advantages and disadvantages and their possible application in processing of legumes.

Keywords: legume processing, biosensors, quality control, nutritional versatility

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8974 Examining the Role of Tree Species in Absorption of Heavy Metals; Case Study: Abidar Forest Park

Authors: Jahede Tekeykhah, Seyed Mohsen Hossini, Gholamali Jalali

Abstract:

Industrial and traffic activities cause large amounts of heavy metals enter into the atmosphere and the use of plant species can be effective in assessing and reducing air pollution by metals. This study aimed to investigate the adsorption level of heavy metals in leaves of Fraxinus rotundifolia, Robinia, Platanus orientalis, Platycladus orientalis and Pinus eldarica trees in Abidar forest park. For this purpose, samples leaves of the trees were prepared from the contaminated and control areas in each region in 3 stations with 3 replicates in mid-August and finally 90 samples were sent to the laboratory. Then, the concentrations of heavy metals were measured by graphite furnace. To do this, factorial experiment based on a completely randomized design with two factors of location on two levels (contaminated area and control area) and the factor of species on five levels (Fraxinus rotundifolia, Robinia, Platanus orientalis, Platycladus orientalis and Pinus eldarica) with three replications was used. The analysis of collected data was performed by SPSS software and Duncan's multiple range test was used to compare the means. The results showed that the accumulation of all metals in the leaves of most species in the infected area with a significant difference at 95% level was higher than the control area. In the contaminated area, with a significant difference at 5% level, the highest accumulations of metals were observed as the following: lead, cadmium, zinc and manganese in Platanus orientalis, nickel in Fraxinus rotundifolia and copper in Platycladus orientalis.

Keywords: airborne, tree species, heavy metals, absorption, Abidar Forest Park

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8973 Motivating Factors to Use Electric Vehicles Based on Behavioral Intention Model in South Korea

Authors: Seyedsamad Tahani, Samira Ghorbanpour

Abstract:

The global warming crisis forced humans to consider their place in the world and the earth's future. In this regard, Electric Vehicles (EVs) are a significant step toward protecting the environment. By identifying factors that influence people's behavior intentions toward using Electric Vehicles (EV), we proposed a theoretical model by extending the Technology Acceptance Model (TAM), including three more concepts, Subjective Norm (SN), Self-Efficacy (SE), and Perceived Behavior Control (PBC). The study was conducted in South Korea, and a random sample was taken at a specific time. In order to collect data, a questionnaire was created in a Google Form and sent via Kakao Talk, a popular social media application used in Korea. There were about 220 participants in this survey. However, 201 surveys were completely done. The findings revealed that all factors in the TAM model and the other added concepts such as subjective norms, self-efficacy and perceived behavior control significantly affect the behavioral intention of using EVs.

Keywords: electric vehicles, behavioral intention, perceived trust, perceived enjoyment, self-efficacy

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8972 Determinants of Multidrug-Resistant Tuberculosis in Patients Who Underwent First-Line Treatment in Addis Ababa: A Case Control Study

Authors: Selamawit Hirpa, Girmay Medhin, Belaineh Girma, Muluken Melese, Alemayehu Mekonen, Pedro Suarez, Gobena Ameni

Abstract:

Worldwide, there were 650,000 multi-drug resistant tuberculosis (MDR-TB) cases in 2010. Ethiopia is 15th among the 27 MDR-TB high-burden countries. A case control study was conducted at St. Peter Hospital and five health centers in Addis Ababa. Cases were MDR-TB patients who were in treatment at St. Peter Hospital during the study period. Controls were patients who were on first-line anti-TB treatment and were registered as cured or having completed treatment in the period 9 April 2009– 28 February 2010, in five health centers. A structured interview questionnaire was used to assess factors that could potentially be associated with the occurrence of MDR-TB. Factors that were significantly associated with MDR-TB: drug side effects during first-line treatment (adjusted odds ratio (AOR): 4.5, 95% CI; 1.9 - 10.5); treatment not directly observed by a health worker (AOR = 11.7, 95% CI; 4–34.3); and retreatment with the Category II regimen (P = 0.000).

Keywords: adherence to TB treatment, MDR-TB, TB treatment, TB treatment regimens

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8971 In vitro Control of Mycosphaerella arachidis Deighton the Early Leaf Spot Disease Pathogen of Groundnut by the Extracts from Six Medicinal Plants

Authors: Matthew Omoniyi Adebola, Jude E Amadi

Abstract:

Ground nut (Arachis hypogaea) is one of the most popular commercial crops in Nigeria. Its suc-cessful production has been drastically affected by early leaf spot disease caused by Mycosphae-rella arachidis Deighton. In vitro control of the pathogen by six medicinal plants (Entada afri-cana, Vitex doniana, Lawsonia inermis, Azadirachta indica, Acalypha hispida and Nuaclea lati-folia) was assessed in this study. The extracts of the plants were prepared using cold and hot wa-ter and alcohol. The pathogen was isolated from ground nut infected with early leaf spot disease. The results revealed a great significant difference (P<0.05) in yield of extracts between cold water, hot water, and alcohol extracts. A significant difference (P<0.05) was observed in percentage concentrations of the various phytochemical constituents present in the extracts. Flavonoids per-centage concentration was the highest (0.68 - 1.95%) followed by saponnin(0.09-1.53%) in N. latifolia extracts. Steroiods had the least percentage concentrations (0.00- 0.09%)followed by terpenoids(0.02–0.71%) and proanthocyannin (0.05 – 0.86%). N. latifolia extracts produced the highest percentage concentrations (0.07–1.95%) of all the phytochemicals followed by A. indi-ca(0.05–1.64%)and least concentrations were obtained in A. hispidia(0.09 – 0.87%)and V. do-niana (0.00–0.88%). The extracts inhibited spore germination and growth of M. arachidis. The inhibition by alcohol extracts was high and significantly different (P>0.05) from cold and hot water extracts. Alcohol extract of L. inermis gave 100% spore germination inhibition followed by N. latifolia and A.indica with 97.75% and 85.60% inhibition respectively. Therefore, field trials of these six medicinal plants on the control of early leaf spot disease of ground nut are rec-ommended.

Keywords: groundnut, phytochemicals, medicinal plants, extracts, inhibition

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8970 Designing a Method to Control and Determine the Financial Performance of the Real Cost Sub-System in the Information Management System of Construction Projects

Authors: Alireza Ghaffari, Hassan Saghi

Abstract:

Project management is more complex than managing the day-to-day affairs of an organization. When the project dimensions are broad and multiple projects have to be monitored in different locations, the integrated management becomes even more complicated. One of the main concerns of project managers is the integrated project management, which is mainly rooted in the lack of accurate and accessible information from different projects in various locations. The collection of dispersed information from various parts of the network, their integration and finally the selective reporting of this information is among the goals of integrated information systems. It can help resolve the main problem, which is bridging the information gap between executives and senior managers in the organization. Therefore, the main objective of this study is to design and implement an important subset of a project management information system in order to successfully control the cost of construction projects so that its results can be used to design raw software forms and proposed relationships between different project units for the collection of necessary information.

Keywords: financial performance, cost subsystem, PMIS, project management

Procedia PDF Downloads 107
8969 Analysis of Flow Dynamics of Heated and Cooled Pylon Upstream to the Cavity past Supersonic Flow with Wall Heating and Cooling

Authors: Vishnu Asokan, Zaid M. Paloba

Abstract:

Flow over cavities is an important area of research due to the significant change in flow physics caused by cavity aspect ratio, free stream Mach number and the nature of upstream boundary layer approaching the cavity leading edge. Cavity flow finds application in aircraft wheel well, weapons bay, combustion chamber of scramjet engines, etc. These flows are highly unsteady, compressible and turbulent and it involves mass entrainment coupled with acoustics phenomenon. Variation of flow dynamics in an angled cavity with a heated and cooled pylon upstream to the cavity with spatial combinations of heat flux addition and removal to the wall studied numerically. The goal of study is to investigate the effect of energy addition, removal to the cavity walls and pylon cavity flow dynamics. Preliminary steady state numerical simulations on inclined cavities with heat addition have shown that wall pressure profiles, as well as the recirculation, are influenced by heat transfer to the compressible fluid medium. Such a hybrid control of cavity flow dynamics in the form of heat transfer and pylon geometry can open out greater opportunities in enhancement of mixing and flame holding requirements of supersonic combustors. Addition of pylon upstream to the cavity reduces the acoustic oscillations emanating from the geometry. A numerical unsteady analysis of supersonic flow past cavities exposed to cavity wall heating and cooling with heated and cooled pylon helps to get a clear idea about the oscillation suppression in the cavity. A Cavity of L/D 4 and aft wall angle 22 degree with an upstream pylon of h/D=1.5 mm with a wall angle 29 degree exposed to supersonic flow of Mach number 2 and heat flux of 40 W/cm² and -40 W/cm² modeled for the above study. In the preliminary study, the domain is modeled and validated numerically with a turbulence model of SST k-ω using an HLLC implicit scheme. Both qualitative and quantitative flow data extracted and analyzed using advanced CFD tools. Flow visualization is done using numerical Schlieren method as the fluid medium gives the density variation. The heat flux addition to the wall increases the secondary vortex size of the cavity and removal of energy leads to the reduction in vortex size. The flow field turbulence seems to be increasing at higher heat flux. The shear layer thickness increases as heat flux increases. The steady state analysis of wall pressure shows that there is variation on wall pressure as heat flux increases. Shift in frequency of unsteady wall pressure analysis is an interesting observation for the above study. The time averaged skin friction seems to be reducing at higher heat flux due to the variation in viscosity of fluid inside the cavity.

Keywords: energy addition, frequency shift, Numerical Schlieren, shear layer, vortex evolution

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8968 Assessment of Water Resources and Inculcation of Controlled Water Consumption System

Authors: Vakhtang Geladze, Nana Bolashvili, Tamazi Karalashvili, Nino Machavariani, Vajha Neidze, Nana Kvirkvelia, Tamar Chichinadze

Abstract:

Deficiency of fresh water is a vital global problem today. It must be taken into consideration that in the nearest future fresh water crisis will become even more acute owing to the global climate warming and fast desertification processes in the world. Georgia has signed the association agreement with Euro Union last year where the priority spheres of cooperation are the management of water resources, development of trans-boundary approach to the problem and active participation in the “Euro Union water initiative” component of “the East Europe, Caucasus and the Central Asia”. Fresh water resources are the main natural wealth of Georgia. According to the average water layer height, Georgia is behind such European countries only as Norway, Switzerland and Austria. The annual average water provision of Georgia is 4-8 times higher than in its neighbor countries Armenia and Azerbaijan. Despite abundant water resources in Georgia, there is considerable discrepancy between their volume and use in some regions because of the uneven territorial distribution. In the East Georgia, water supply of the territory and population is four times less than in the West Georgia.

Keywords: GIS, water consumption, water management, water resources

Procedia PDF Downloads 418
8967 Finite Element Method for Calculating Temperature Field of Main Cable of Suspension Bridge

Authors: Heng Han, Zhilei Liang, Xiangong Zhou

Abstract:

In this paper, the finite element method is used to study the temperature field of the main cable of the suspension bridge, and the calculation method of the average temperature of the cross-section of the main cable suitable for the construction control of the cable system is proposed; By comparing and analyzing the temperature field of the main cable with five diameters, a reasonable diameter limit for calculating the average temperature of the cross section of the main cable by finite element method is proposed. The results show that the maximum error of this method is less than 1℃, which meets the requirements of construction control accuracy; For the main cable with a diameter greater than 400mm, the surface temperature measuring points combined with the finite element method shall be used to calculate the average cross-section temperature.

Keywords: suspension bridge, main cable, temperature field, finite element

Procedia PDF Downloads 156