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The main objective of Load Frequency Control (LFC) is to effectively manage the power output of an electric generator at a designated site, in order to maintain system frequency and tie-line loading within desired limits, in reaction to fluctuations. The adaptive neuro-fuzzy inference system (ANFIS) is a controller that integrates the beneficial features of neural networks and fuzzy networks. The comparative analysis of Artificial Neural Network (ANN), Adaptive Neuro-Fuzzy Inference System (ANFIS), and Proportional-Integral-Derivative (PID)-based methodologies demonstrates that the suggested ANFIS controller outperforms both the PID controller and the ANN controller in mitigating power and frequency deviations across many regions of a hybrid power system. Two systems are analysed and represented using mathematical models. The initial system comprises a thermal plant alongside photovoltaic (PV) grid-connected installations equipped with maximum power point trackers (MPPT). The second system comprises hydroelectric systems. The MATLAB/Simulink software is employed to conduct a comparative analysis of the outcomes produced by the controllers.

Photovoltaic (PV) powered water pumping systems utilizing induction motors are becoming increasingly popular in different regions. The lack of storage devices in the system enhances its cost-efficiency. Efficient energy management is crucial for maintaining power balance within the system, and this can be achieved through the implementation of an effective control technique. A small signal analysis is performed to optimize the parameters of the controllers used in order to analyze the system. The dynamic behavior of the PV-based water pumping system, which is powered by an induction motor and regulated by a vector controller, is analyzed by converting its non-linear model into a linear model. The paper discusses the design of parameters for two PI controllers utilized to regulate the PV terminal voltage and motor speed, based on the transfer function derived from the linear model. The study also showcases the small signal function’s reaction through MATLAB, with adjustments made to the reference dc-link voltage. Additionally, a comprehensive stepby-step mathematical analysis is included to enhance the overall understanding and analysis of the system.

This review article delves into the strategic integration of renewable energy sources within smart cities, emphasizing the role of electric vehicles (EVs) in ensuring stability. Smart cities, at the forefront of sustainable urban development, prioritize energy systems that are both clean and renewable. The integration of various renewable energy resources, including solar, wind, geothermal, hydropower, ocean, and biofuels, into the energy systems of smart cities is explored, considering both technical and economic aspects. The rapid adoption of these technologies provides a foundation for a low-carbon economy, ensuring a cleaner and more sustainable urban environment. However, challenges persist, particularly in optimizing energy systems for renewable integration, stability, operational range, and cost-effectiveness. Additionally, the evolution of smart cities has brought forth advanced energy conservation systems, addressing energy management at both building and city levels. Innovative solutions, such as advanced infrastructure and energy trading strategies in distributed systems, are proposed. The role of EVs in the smart grid is also highlighted, addressing challenges posed by renewable energy’s intermittent output. The potential of EVs to counteract these fluctuations, especially under the vehicle-to-grid (V2G) framework, is discussed, offering insights into future research avenues for a harmonious and sustainable energy ecosystem in smart cities.

We provide two proofs that the conjecture of Artin-Tate for a fibered surface is equivalent to the conjecture of Birch-Swinnerton-Dyer for the Jacobian of the generic fibre. As a byproduct, we obtain a new proof of a theorem of Geisser relating the orders of the Brauer group and the Tate-Shafarevich group.

This review provides a thorough analysis of the progress made in smart polymer composite materials, which have recently been seen as potential game-changers in areas such as construction, aerospace, biomedical engineering, and energy. This article emphasizes the distinctive characteristics of these materials, including their responsiveness to stimuli like temperature, light, and pressure, and their potential uses in different industries. This paper also examines the difficulties and restrictions associated with the creation and utilization of smart polymer composite materials. This review seeks to provide a thorough understanding of smart polymer composite materials and their potential to offer innovative solutions for a variety of applications.

Despite the higher efficiency advantage, the cost reduction of PV technology has been more successful compared to the dish Stirling engine (DSE) due to the large market volume and sturdy competition. Irrespective of the types of source, there exists a potential of waste heat recovery from Stirling engines operating at higher temperature regime. Accordingly, to make DSE commercially viable and efficient, innovative ways such as hybridization (combing a bottoming cycle), Co-generation, Tri-generation etc. need to be explored. In this paper, the techno-economic feasibility of hybridization of a typical solar DSE with a bottoming organic Rankine cycle (ORC) via. a heat recovery vapour generator (HRVG) is explored. The overall energetic and exergetic efficiency of the DSE has been improved by 5.79% and 5.64% while recovering the waste heat through a bottoming ORC. The design and effective incorporation of the HRVG with cooler side of the Stirling engine is identified to be crucial for the overall exergetic performance of solar Stirling-ORC. Further, the economic feasibility of a solar String-ORC combination is evaluated in terms of levelized cost of electricity (LCOE) and payback period. Both LCOE and payback period are found to be in comparable range with the PV technology.

Job placement is becoming an uphill task for new graduates when they do not have the relevant knowledge to start up on their own. This happens when their education is either sub-standard, rendered obsolete upon graduation or cannot be translated into practice at their respective workplaces. Such a shortcoming in the broadcasting industry is not with the provision of training or the supply of skilled manpower. It is rather the continuous disruption of technology when graduates require more than operational knowledge. In the absence of ‘job-fit graduates’ the broadcasting industry looks out for the best talents outside of their traditional marketplace. To address this fallout, the industry is looking to recruit new talents with emerging computing knowledge instead of the traditional Mass Communication discipline. This empirical study explores the skills shortage in the broadcasting industry from the perspective of “Challenges of Industrial Revolution 4.0 in higher education (MyHE 4.0). Qualitative data was gathered from stakeholders, training providers and vendors. Two major findings: 1) The need for talents transformation to a modern converged setting in broadcasting; and 2) The establishment of pathways to ‘Job-Fit’ training in the broadcasting industry, have emerged from the study. The study proposes six recommendations in support of the transformation in the broadcasting industry.

A 48 year old female presented to causality with high grade fever with rigors and chills, right upper abdominal pain and jaundice of one day duration. She had a past history of similar episode one month back for which she had undergone endoscopic biliary drainage. Hemogram revealed leucocytosis with polymorphonuclear cell predominance. Liver function tests; total bilirubin 8.4mg/dl, direct bilirubin 4.9mg/dl, alanine aminotransferase 96 U/L, aspartate aminotransferase 84 U/L, alkaline phosphatase 438 U/L and normal albumin 4.1gm/dl. Serum electrolytes and renal function tests were within normal limits. Plain x-ray abdomen revealed a radio-opaque foreign body in the left side of abdomen. Ultrasound abdomen revealed a mildly enlarged liver with dilated intrahepatic biliary tree, multiple gall stones and a dilated common bile duct. A provisional diagnosis of distally migrated double pigtailed biliary stent and cholangitis was made. Patient was managed with urgent endoscopic retrograde cholangio-pancreatography with stenting and started on parenteral antibiotics as well as other supportive measures. On the second day of admission stent passed off with fecal matter and repeat abdominal x-ray revealed no foreign body in the colon. Patient improved with treatment and is being planned for cholecystectomy. Stent migration is one of the complications of biliary stenting. Distal migration is more common than proximal migration. Risk of migration is more for plastic (5-10%) and covered metallic stents (3-12%) compared to uncovered metallic stents (1%). Complications of stent migration include recurrence of cholangitis, pancreatitis and rarely intestinal obstruction or perforation. Stent modifications like creation of pig tails (single or double) or side flaps have been tried to reduce the risk of stent migration but with limited success. With the improvements in endoscopic techniques and expertise biliary stenting is more frequently done in the setting of acute cholangitis. Distally migrated stents may be identified as an intra-abdominal foreign body before it passes off in the stool. We hope this clinical image will introduce the primary care physicians to the radiological appearance in a case of distally migrated double pig tailed biliary stent.

This study examines social network diversity in urban areas relative to residents’ usage of information and communication technologies (ICTs). Individual-level variation in social network diversity was measured using position generator data collected as part of a survey conducted in Malaysia’s Klang Valley (N = 808). Regression analyses were performed to assess the extent to which network diversity is related to ICTs. We find that most ICTs have a negative effect on diversity. Only frequent use of the Internet at work, mobile access to the Internet, and reading online news or blogs contribute positively to diversity. Findings support both a tendency toward ‘networked individualism’ and the more recent ‘glocalization’ thesis that some ICTs may also afford participation within local space rather than only across distant space.

High efficiency in power converters means less power wasted, which implies reduction in heat sink requirement, thereby small in size and less in weight. This power loss reductions in space application leads to smaller solar panels and less fuel on-board, hence reduces the spacecraft size, weight and launch cost. One of the major challenges for power converters in space application is to boost their efficiency, to reduce thermal dissipation problems. In this paper, design and implementation of an ultra-high efficiency isolated bi-directional dc-dc converter utilizing GaN devices is presented. Loss modelling of the GaN converter is also included in this paper. The converter has achieved a maximum measured efficiency of 98.8% in both directions of power flow, using the same power components. Hardware prototype of the converter along with the measured efficiency curve is also presented in this paper.

The usage of cutting fluid in the machining operations will not only poses health risk to the workers but also creates environmental challenges associated with fluid treatment and disposal. The objective of this review paper is to identify present cooling method in dry machining and novel feature than can be included in the cooling system for a better heat removal which tend to increase machining performance. From the review study, it shows that cooling method by internal manner is most widely been researched because researcher believes that it has a promising future in adaptive machining to produce a contamination free products which supports the green manufacturing concept. The suggested novel feature is ecologically desirable and it will become as a necessity for improving the performance of dry machining in the near future.

Symptomatic gastric malignancy usually presents with symptoms which mimic peptic ulcer disease.Usual presenting features include weight loss and abdominal pain. Other symptoms include nausea, vomiting, dysphagia, melena and early satiety. Gastric malignancy presenting with hemetemesis, macular skin lesions of DIC and low backache due to bone metastasis from the primary is rare. Also bone metastasis in gastric cancer in the absence of hepatic metastasis is also rare.

This work presents a review of recent literature in intelligent school transportation frameworks, particularly focusing on route planning, real time vehicle and children tracking. The focus on route planning and tracking is to identify the hidden practical problems and threats present in school transportation, bearing in mind safety. Different methods and technologies used for route planning and vehicle as well as children tracking are reviewed. A discussion is provided on the current frameworks along with the challenges and future research direction.

This article examines the role of culture in the ethnic conflict and strife in Sri Lanka. The general aim is to achieve an understanding of the nationalist process, the force of nationalist ideas and traditions in motivating action-action that is often violent and intolerant-and to demonstrate the value of a cultural approach to the understanding of modern societies. Culture has been examined in two ways here, namely, the dramaturgic approach to culture which emphasizes the expressive dimensions of culture, and the politics of culture or the political culture approach, whereby cultural manifestations are utilized effectively to maintain power between groups. The article concludes that the SinhaleseTamil conflict is a product of modem politics, and culture has been used effectively to legitimate rival nationalisms in Sri Lanka.

Irradiation and use of preservatives are routine procedures to control bio-burden in solid herbal dosage forms. Use of steam or pasteurization is even though reported in the literature, not many studies are available with respect to its application in reducing the bio-burden in herbal drug formulations. Hence, we undertook a series of studies to explore the suitability of pasteurization as a method to reduce bio-burden during formulation and development of herbal dosage forms, which will pave the way for preparing preservative-free formulations. Optimized Ashoka (Saraca indica) tablets were formulated and developed. The optimized formula was then subjected to pasteurization during formulation, with an aim to keep the microbial count well within the limits of pharmacopoeial standards. Then, three variants of the optimized Ashoka formulation - with preservative, without preservative and formulation without preservative and subjected to pasteurization, were compared by routine in-process parameters and stability studies. The results obtained indicate that Ashoka tablets manufactured by inclusion of t he pasteurization technique not only showed the bio-burden to be within the limits of pharmacopoeial standards, but also exhibited the compliance with other parameters, such as stability and quality. The outcome of this pilot study shows that pasteurization can be employed as a distinctive method for reducing bio-burden during the formulation and development of herbal dosage forms, such as tablets. [ABSTRACT FROM AUTHOR]