Evaluation of Time-Critical Communications for IEC 61850-Substation Network Architecture

Present-day developments, in electrical power transmission and distribution, require considerations of the status quo. In other meaning, international regulations enforce increasing of reliability and reducing of environment impact, correspondingly they motivate developing of dependable systems. Power grids especially intelligent (smart grids) ones become industrial solutions that follow standardized development. The International standardization, in the field of power transmission and distribution, improve technology influences. The rise of dedicated standards for SAS (Substation Automation Systems) communications, such as the leading International Electro-technical Commission standard IEC 61850, enforces modern technological trends in this field. Within this standard, a constraint of low ETE (End-to-End) latency should be respected, and time-critical status transmission must be achieved. This experimental study emphasis on IEC 61850 SAS communication standard, e.g. IEC 61850 GOOSE (Generic Object Oriented Substation Events), to implement an investigational method to determine the protection communication delay. This method observes GOOSE behaviour by adopting monitoring and analysis capabilities. It is observed by using network test equipment, i.e. SPAN (Switch Port Analyser) and TAP (Test Access Point) devices, with on-the-shelf available hardware and software solutions

Dependability Optimization of Process-level Protection in an IEC-61850-Based Substation

International audiencePower substations are intensively renovated toward using information and communication technologies such as object oriented modeling and Ethernet networks. In the last two decades, Substation automation systems used capabilities of network communication services adopted from sophisticated international standardization such as IEC 61850. Distributed safety related functions take advantage of these technologies to protect the process-level equipment. Substation devices such as intelligent electronic devices, measurement units and circuit breaker controllers, with new capabilities, i.e. enabling IEC 61850, are integrated to build the protection and control functions that form the safety-related system. The objective of this research is to evaluate quantitatively the dependability for transformer protection architectures in the bay level.Safety integrity levels model, described in both IEC 62061 and IEC 61508, gives measurements for safety integrity levels according to the probability of failure. The determination of these levels is an approach to estimate system dependability

Experimental Evaluation of an IEC 61850-Station Bus Communication Reliability

National audienceRecent improvements, in electrical power transmission and distribution, require considerations of existing regulations that enforce increasing of reliability and reducing of environment impact. Smart grids become industrial solutions that follow standardized development. These technologies are affected by international standardization in the field of power transmission and distribution. This study emphasis on modern SAS (Substation Automation System) communication standards, e.g. IEC 61850 GOOSE (Generic Object Oriented Substation Events), to present an experimental method to calculate End-To-End delay by utilizing monitoring capabilities and using network equipment such as SPAN and TAP devices

Performance Evaluation of IEC 61850 safety-related communication architecture

International audienceRecent improvements, in electrical power transmission and distribution, require considerations of existing regulations that enforce increasing of reliability and reducing of environment impact. Smart grids become industrial solutions that follow standardized development. It is used to satisfy both the electrical energy supply from producers to consumers and the need for consumers' data transmission to electrical utility and providers. This technology is affected by international standardization in the field of power transmission and distribution. Modern electrical substations, i.e. electrical transmission and distribution stations, are part of smart grids. These substations follow new technological trends [1]. The IEC 61850 standard consists of 10 parts to enforce interoperability between different manufactured devices, e.g. intelligent electronic device (IED), in the substation communication systems [2]. The standard uses high speed time-critical communication to exchange events and states between substation devices. This standard sets a latency constraint to achieve a response time of less than four milliseconds for critical event communications, especially in the protection and automation fields [3]. One of the objectives of the current research is to evaluate latency of Ethernet based GOOSE (General Object Oriented Substation Events), i.e. time-critical messages , transmission for both message priority and time delay. In particular, to evaluate theses parameters, especially when network redundancy is existed, a simulation model scenario is developed

Oral health in Libya: addressing the future challenges

Libya is a vast country situated in North Africa, having a relatively better functioning economy with a scanty population. This article is the first known attempt to review the current state of oral health care in Libya and to explore the present trends and future challenges. Libyan health system, oral health care, and human resources with the present status of dental education are reviewed comprehensively. A bibliographic study of oral health research and publications has been carried out. The results point toward a common indicator that oral healthrelated research is low. Strategies have to be developed to educate the medical and dental professionals, to update the current curriculum and enable the system to be competent in all aspects of oral health care management.Keywords: oral health; oral health research; oral health care; dental research; dental education; Liby

Prevalence of Plasmodium vivax species in Elhajyosife area in Shergalnile locality in Khartoum State

Background: Plasmodium vivax malaria has been recognized as an important cause of morbidity in several African countries. The prevalence was previously estimated as 12.5% in Khartoum. These estimates are observed to be rising and spreading continuously. Aim: The present study was undertaken to investigate the situation of distribution of P. vivax malaria in Elhajyousiff area in Khartoum State-Sudan. Methods: Cross-sectional malaria surveys carried out in Elhajyousiff area (Khartoum State) during the period of August 2021 to September 2021 .Atotal number of 250 blood samples were examined by microscopical examination. The samples were collected from different centers in Elhajyousiff area (Albanjadeed Hospital, Almaygoma Health Center and Alsheeda Nada Health Center). All samples were examined by direct microscopy for plasmodium species using blood film (Thick and thin). Results: From 250 samples there were 241(96.4%) samples negative, 5(2.0%) samples were positive for P.falciparum and 4(1.6%) samples were positive for P.vivax. The P. falciparum showed as more common species in area. Conclusions: Even though malaria in Shergalnile locality is still largely recognized to Plasmodium falciparum, P. vivax has been growing with worrying proportions and spreading to new areas. The emergence and marked increase of P. vivax poses new challenges to malaria treatment and control in Elhajyousiff area

Optimizing the Thermal Resistance of Concrete Using The Palm Tree Fronds Fibers

In the past few years, the issue of global warming has become increasingly visible. Record high as well as record low temperatures are being broken worldwide. Snow is melting in the poles and less sunrays are being reflected causing more temperature to be absorbed by Earth. One of the main reasons of global warming is burning the fossil fuels for producing electrical energy. One of the household items that consumes a lot of electricity is the air conditioner. In the U.S. alone, it is estimated that every airconditioned house produces two tons of carbon dioxide every year. It is believed that if better insulation systems are used in our houses, especially in the GCC area, the use of air conditioners can be optimized to consume less electricity. The main aim of this project is to come up with an environmentally friendly building insulation system that reduces the electrical consumption used in air conditioners in our houses. PTF was prepared and used as a natural free resource that is available locally in the GCC. Several mixes with different PTF ratios have been prepared and tested for thermal insulation and structural integrity. The results indicate a significant improvement in the R value of concrete. This additive also affected the compressive strength of concrete. It was found that replacing of fine aggregate with less than 1% of PTF will increase the R value of concrete without affecting the strength capacity significantly

Cortico-hippocampal computational modeling using quantum-inspired neural networks

Many current computational models that aim to simulate cortical and hippocampal modules of the brain depend on artificial neural networks. However, such classical or even deep neural networks are very slow, sometimes taking thousands of trials to obtain the final response with a considerable amount of error. The need for a large number of trials at learning and the inaccurate output responses are due to the complexity of the input cue and the biological processes being simulated. This article proposes a computational model for an intact and a lesioned cortico-hippocampal system using quantum-inspired neural networks. This cortico-hippocampal computational quantum-inspired (CHCQI) model simulates cortical and hippocampal modules by using adaptively updated neural networks entangled with quantum circuits. The proposed model is used to simulate various classical conditioning tasks related to biological processes. The output of the simulated tasks yielded the desired responses quickly and efficiently compared with other computational models, including the recently published Green model

Association of TNF-α, IFN-γ, IL-6, and IL-10 with different clinical manifestations of hepatitis B infection

Cytokines have a crucial part in the pathogenesis, persistence of infection, and prognosis of hepatitis B virus (HBV) infection as HBV does not cause direct liver destruction; rather, disease-related complications and prognosis are more associated with immune system action, specifically cytokines such as TNF-α, IFN-γ, IL-6, IL-10, and other cytokines. This study sought to link TNF-, IFN-, IL-6, and IL-10 to various clinical manifestations of HBV infection. Ninety sera were taken from HBV-infected patients, 30 (33.3%) of whom had liver cirrhosis, 30 (33.3%) were HBV carriers, 19 (21.2%) were acute HBV patients, and 11 (12.2%) were recently HBV infected. ELISA was used to determine the serum levels of TNF-α, IFN-γ, IL-6, and IL-10. HBV-infected patients with liver cirrhosis had considerably higher mean serum levels of IFN-γ (P=0.005) and IL-10 (P=0.003), but TNF-α and IL-6 were significantly higher in recent HBV-infected patients (P values 0.034 and 0.004, respectively). There were substantial changes in mean serum levels of TNF-α, IFN-γ, IL-6, and IL-10 at different phases of HBV infection, implying a role for cytokines in HBV etiology, chronicity, and consequences

Association of respiratory symptoms and lung function with occupation in the multinational Burden of Obstructive Lung Disease (BOLD) study

Background Chronic obstructive pulmonary disease has been associated with exposures in the workplace. We aimed to assess the association of respiratory symptoms and lung function with occupation in the Burden of Obstructive Lung Disease study. Methods We analysed cross-sectional data from 28 823 adults (≥40 years) in 34 countries. We considered 11 occupations and grouped them by likelihood of exposure to organic dusts, inorganic dusts and fumes. The association of chronic cough, chronic phlegm, wheeze, dyspnoea, forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1)/FVC with occupation was assessed, per study site, using multivariable regression. These estimates were then meta-analysed. Sensitivity analyses explored differences between sexes and gross national income. Results Overall, working in settings with potentially high exposure to dusts or fumes was associated with respiratory symptoms but not lung function differences. The most common occupation was farming. Compared to people not working in any of the 11 considered occupations, those who were farmers for ≥20 years were more likely to have chronic cough (OR 1.52, 95% CI 1.19–1.94), wheeze (OR 1.37, 95% CI 1.16–1.63) and dyspnoea (OR 1.83, 95% CI 1.53–2.20), but not lower FVC (β=0.02 L, 95% CI −0.02–0.06 L) or lower FEV1/FVC (β=0.04%, 95% CI −0.49–0.58%). Some findings differed by sex and gross national income. Conclusion At a population level, the occupational exposures considered in this study do not appear to be major determinants of differences in lung function, although they are associated with more respiratory symptoms. Because not all work settings were included in this study, respiratory surveillance should still be encouraged among high-risk dusty and fume job workers, especially in low- and middle-income countries.publishedVersio