550 research outputs found

    Influence of single and multiple dry bands on critical flashover voltage of silicone rubber outdoor insulators: simulation and experimental study

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    Dry band formation on the surface of outdoor insulators is one of the main reasons leading to flashover and power outages. In this paper, a dynamic arc model is proposed for single and multiple dry bands configuration to predict the critical flashover voltage for silicone rubber outdoor insulators. An arc is modelled as a time dependent impedance consisting of a Resistor Inductor Capacitor (RLC) circuit. The effect of dry band location and existence of multiple dry bands on critical flashover voltage is investigated. To validate the proposed model, experiments were conducted in a climate chamber under controlled environmental conditions on rectangular silicone rubber sheets polluted using improved solid layer method based on IEC 60,507. Tests were conducted at different dry band configurations and pollution severity levels. A good correlation was found between experimental results and simulation results. This model can provide a good foundation for the development of mathematical models for station post insulators having multiple dry and clean bands and can be used in the design and selection of outdoor insulators for polluted conditions

    Environmental Concerns in Capital Budgeting: Impact on Firms Performance

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    Product manufacturing often has negative effects on the environment. Pollution, waste disposal, recycling, insurance, and public relations associated with these effects have become a focus in the 21st century. Within the last two decades, the concern for these environmental effects has grown. Companies and upper management are held financially responsible for negative environmental impacts. This new financial responsibility must be incorporated into the traditional capital budgeting process. To measure the impact of capital budgeting decisions on firm’s performance while incorporating environmental concerns. The research objective of this study is to measure the impact of capital budgeting decisions on firm’s performance and to observe the capital budgeting decisions which are environmentally friendly taken by firms to increase revenues. The research will be based upon a quantitative design. The researcher will examine the behaviour of different environmental decisions through asking questions with the help of survey and document analysis, and will try to find out the basic idea of authorized professionals regarding the impact of environmental policies effecting firms performance. The research strategy for this research is that the surveys will be conducted and document analysis of the firms in the manufacturing sector of Pakistan will be done which includes cement, fertilizers, chemical, and sports industries. In the rapid industrialization era where life is becoming simple and easier for all human beings on the other hand it is suffocating for the Global Climate. The independent variable Environmental Concerns is found to have a direct impact on the performance of the firms as the pressure from Media, Government policies, Investors and employees is forcing the firms to adopt environmentally friendly business activities which is resulting in increased revenue for the firms. Those firms who have not adopted any environmentally friendly business practices, and plan to make any capital budgeting decisions in the future will surely result positively in the form of increased revenues, more customers and successfully achieving the vision of the company

    How the Students’ Competitive and Collaborative Styles of Learning are Affected by Personality Traits at the University Level

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    Investigating how personality traits affect competitive and collaborative learning is the goal of the current study. When examining the influence of personality traits on learning styles, Big Five Theory was employed. Two hundred students were casually picked using the non-probability selection approach for this descriptive study design. After translation into the native language, a large-scale portfolio and the Grasha-Riechmann Scales of Student Learning Skills were utilized. Cronbach's alpha provided proficient estimation, pilot testing, and consistency, which all confirmed the instrument’s validity (α = 0.94). Five elements correlated with students' learning styles, including their personality traits. Students may benefit from a teaching approach that considers their unique characteristics and learning styles. Social training, academic achievement, and collaborative chances influenced personality traits and learning

    Harmonic Scalpel Hemorrhoidectomy Vs Milligan-Morgan Hemorrhoidectomy

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    Background: To compare Harmonic Scalpel Hemorrhoidectomy (HSH) with classical Milligan Morgan Hemorrhoidectomy (MMH) in terms of operation time and post-operative pain to establish effectiveness of this novel procedure.Methods: A total of 62 patients planned for excision hemorrhoidecotmy were randomly selected into HSH and MMH groups. Mean operation time was calculated during surgery and pain at time of first defecation was recorded on visual analog scale (VAS).Results: Mean VAS after surgery at time of first defecation was 4.32 (SD 0.909) in HSH group and 6.97 (SD 1.426) in MMH group (p value <0.000). Mean Operation time in HSH group was 18.13 (SD 3.956) minutes and that of MMH group was 22.90 (SD 4.901) minutes (P value <0.000).Conclusion: Harmonic Scalpel Hemorrhoidectomy is better than Milligan Morgan hemorrhoidectom

    Avoiding contingent incidents by quadrotors due to one or two propellers failure

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    With the increasing impact of drones in our daily lives, safety issues have become a primary concern. In this study, a novel supervisor-based active fault-tolerant (FT) control system is presented for a rotary-wing quadrotor to maintain its pose in 3D space upon losing one or two propellers. Our approach allows the quadrotor to make controlled movements about a primary axis attached to the body-fixed frame. A multi-loop cascaded control architecture is designed to ensure robustness, stability, reference tracking, and safe landing. The altitude control is performed using a proportional-integral-derivative (PID) controller, whereas linear-quadratic-integral (LQI) and model-predictive-control (MPC) have been investigated for reduced attitude control and their performance is compared based on absolute and mean-squared error. The simulation results affirm that the quadrotor remains in a stable region, successfully performs the reference tracking, and ensures a safe landing while counteracting the effects of propeller(s) failures

    Performance Analysis of Hardware Protection & System Security in Different Operating Systems

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    The intention of article is to protect the hardware, which includes protecting CPU, I/O, and memory. This article portrays and relates the security in different operating systems. Therefore, helping us to choose the best. We can evaluate the security in different operating systems like Windows, UNIX, Linux to secure over all data to access unauthorized users

    Formulation and evaluation of Ketoprofen cream containing natural anti-inflammatory agent curcuma longa in treatment of rheumatoid arthritis

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    Non-Steroidal Anti-Inflammatory drugs have their origin as the derivatives of plants which were observed to have strong analgesic and anti-inflammatory effects in various disease states. Ketoprofen is a better tolerated NSAID because of its limited numbers of adverse effects and topical formulation has excellent permeation and absorption into the skin. The present investigation was to develop novel Ketoprofen cream formulation in combination of most effective and potent anti-inflammatory agent curcuma longa, which is reported to possess strong anti-inflammatory effects in Rheumatoid Arthritis and Osteoarthritis, according to the study by university of Arizona researchers. Combination of Ketoprofen and curcuma longa is good rational, where curcuma longa produces synergistic anti-inflammatory effects with ketoprofen. Formulation containing fixed concentrations (3%) of ketoprofen with curcuma longa was prepared. To access the efficacy of formulation stability studies, spread ability, tube extrudability, viscosity, pH, skin irritation test, in vitro drug diffusion study and anti- inflammatory effects were evaluated. The results obtained were encouraging and formulation containing Ketoprofen (3%) with curcuma longa was found better than alone Ketoprofen cream formulation

    An Efficient & Less Complex Solution to Mitigate Impulsive Noise in Multi-Channel Feed-Forward ANC System with Online Secondary Path Modeling (OSPM)

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    This paper deals with impulsive noise (IN) in multichannel (MC) Active Noise Control (ANC) Systems with Online Secondary Path Modelling (OSPM) employing adaptive algorithms for the first time. It compares performance of various existing techniques belonging to varied computational complexity range and proposes four new methods, namely: FxRLS-VSSLMS, VSSLMS-VSSLMS, FxLMAT-VSSLMS and NSS MFxLMAT-VSSLMS to deal with modest to very high impulsive noise (IN). Simulation results show that these proposed methods demonstrated improved performance in terms of fast convergence speed, lowest steady state error, robustness and stability under impulsive environment in addition to modelling accuracy for stationary as well as non-stationary environment besides reducing computational complexity many folds
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