6 research outputs found
Dengue Outbreaks in Khyber Pakhtunkhwa (KPK), Pakistan in 2017: An Integrated Disease Surveillance and Response System (IDSRS)-Based Report
Dengue Outbreaks in Khyber Pakhtunkhwa (KPK), Pakistan in 2017: An Integrated Disease Surveillance and Response System (IDSRS)-Based Report
Snažni boÄni vjetrovi koji puÅ”u na mostovima i vijaduktima mogu dovesti do gubitka dinamiÄke stabilnosti vozila koja prelaze most. Da bi se omoguÄio nesmetan i siguran promet Äak i u sluÄajevima nepovoljnih vremenskih uvjeta uzrokovanih snažnim boÄnim vjetrom, na mostove se postavljaju zaÅ”titni vjetrobrani. Karakteristike strujanja zraka preko mosta su znaÄajno promijenjene u sluÄaju postavljanja vjetrobrana razliÄitih visina i poroznosti. U okviru ovog rada ispitan je utjecaj visine vjetrobrana te utjecaj poroznosti vjetrobrana na karakteristike strujanja zraka oko vozila koje se nalazi na mostu. Vjetrobran je postavljen samo na uzvodni rub mosta, a za vozilo je koriÅ”ten model Ahmedovog tijela koji je u svim simulacijama postavljen na udaljenost 2 m nizvodno od vjetrobrana. Pri raÄunalnim simulacijama koriÅ”ten je model stacionarnog trodimenzijskog turbulentnog strujanja nestlaÄivog fluida te k-Ļ SST model turbulencije sa standardnim zidnim funkcijama.
Dobiveni rezultati ukazuju na znaÄajan utjecaj vjetrobrana na koeficijente tlaka na povrÅ”ini vozila. Manja poroznost vjetrobrana i veÄa visina vjetrobrana uzrokuju smanjenje koeficijenta tlaka na nastrujavanoj povrÅ”ini vozila. Iako su vrijednosti koeficijenta tlaka na povrÅ”ini vozila za male poroznosti vjetrobrana relativno male, raspodjela vrtložnosti struje zraka sugerira da može doÄi do poveÄanih vrijednosti standardnih devijacija aerodinamiÄkih sila koje djeluju na vozilo.
Karakteristike vjetrobrana imaju bitan utjecaj na raspodjelu brzine strujanja zraka uzvodno od vozila, odnosno u prostoru izmeÄu vjetrobrana i vozila. Smanjenjem poroznosti vjetrobrana se brzine strujanja zraka u tom podruÄju znaÄajno smanjuju. Utjecaj poroznosti vjetrobrana na raspodjelu brzine strujanja zraka u ovom podruÄju je znaÄajniji u odnosu na utjecaj visine vjetrobrana.
AerodinamiÄke sile i momenti zabilježeni na vozilu su znaÄajno smanjeni kada je vjetrobran postavljen na most. Rezultati dobiveni u okviru ovog rada sugeriraju da je, s obzirom na aerodinamiÄke sile koje djeluju na vozilo, optimalna visina vjetrobrana 5 m uz njihovu poroznost u iznosu od 30%.Strong cross winds that commonly blow on bridges and viaducts may cause dynamic instabilities of vehicles crossing the bridge. To allow for safe traffic even in the periods of bad weather conditions such as strong cross winds, bridges are equipped with wind barriers. Flow characteristics around the bridge are significantly modified with respect to the wind barrier height and porosity. In the present work, the influence of wind barrier height and porosity on flow characteristics around the vehicle passing the bridge was studied. The wind barrier was placed on the windward bridge-deck edge only, while the Ahmed body was used as a vehicle. It was placed 2 m downwind of the wind barrier. In the computational simulations, the stationary 3D turbulent incompressible flow was modeled together with the k-Ļ SST turbulence model and standard wall functions.
The obtained results generally show a significant influence of the wind barrier on the pressure coefficients observed on the vehicle surface. Smaller porosity and larger height of the wind barrier causes smaller pressure coefficients on the windward side of the vehicle. Even though the pressure coefficients on the vehicle for the low-porous wind barrier are relatively small, the distribution of the flow vorticity suggests larger values of the standard deviation of the aerodynamic forces acting on the vehicle.
Wind-barrier characteristics proved to have a large influence on the distribution of flow velocity in the area upstream of the vehicle and downstream of the wind barrier. For smaller porosities of the wind barrier, flow velocities in this area are significantly smaller. The influence of the porosity on the distribution of flow velocities in this area is relatively larger compared to the height of the wind barrier.
The aerodynamic forces and moment are generally smaller when the wind barrier is in place. The obtained results suggest that the 5 m high and 30% porous wind barrier is optimal with respect to the aerodynamic forces and moment acting on the vehicle on the bridge
The expected second wave of COVID-19
The pandemic of Coronavirus Disease (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) continues to rise around the globe. As per 15th July 2020, the World Health Organization (WHO) reported 13,119,239 confirmed COVID-19 cases along with 573,752 confirmed deaths globally
Prediction of the optimal hybrid train trajectory by using artificial neural network models
AbstractThis paper presents the development and validation of two artificial neural networks (ANN) models, utilising time and powerābased architectures, to accurately predict key parameters of a hydrogen hybrid train profile and its optimal trajectory. The research employs a hybrid train simulator (HTS) to authenticate the ANN models, which were trained using simulated trajectories from five unique hybrid trains on a designated route. The modelsā performance was evaluated by computing the mean square normalisation error and mean absolute performance error, while the output's reliability was confirmed through the HTS. The results indicate that both ANN models proficiently predict a hybrid train's critical parameters and trajectory, with mean errors ranging from 0.19% to 0.21%. However, the cascadeāforward neural network (CFNN) topology in the timeābased architecture surpasses the feedāforward neural network (FFNN) topology concerning mean squared error (MSE) and maximum error in the powerābased architecture. Specifically, the CFNN topology within the timeābased structure exhibits a slightly lower MSE and maximum error than its powerābased counterpart. Additionally, the study reveals the average percentage difference between the benchmark and FFNN/CNFN trajectories, highlighting that the timeābased architecture exhibits lower differences (0.18% and 0.85%) compared to the powerābased architecture (0.46% and 0.92%).</jats:p
Production of nitrogen fixing Azotobacter (SR-4) and phosphorus solubilizing Aspergillus niger and their evaluation on Lagenaria siceraria and Abelmoschus esculentus
Aims: Current study was aimed to produce nitrogen fixing Azotobacter sp. (SR-4) and phosphorus solubilizers Aspergillus niger (A. niger) and to evaluate their efficiency as biofertilizers for agricultural practices. Methods: Two biofertilizer including nitrogen fixing and phosphorus solubilizing were grown. The nitrogen fixing efficiency of Azotobacter (SR-4) was determined by Kjeldahl method. Similarly, Vanadomoybdate method was used to measure the soluble phosphorus while Heinonen method was used to analyze concentration of phytase and phosphatase in the cultures. Furthermore, both biofertilizers were tested in a field trail on Lagenaria siceraria (bottle gourd) and Abelmoschus esculentus (okra). Results: The Azotobacter (SR-4) strain was found efficient nitrogen fixer as 35.08āmg of nitrogen per gram of carbon was produced after 72āh of fermentation. Similarly, A. niger strain excrete extracellular phosphate solubilizing enzymes such as phytase (133UI in 48āh of fermentation) and phosphatase (170UI in 48āh of fermentation) which can solubilize the rock phosphate and make it available to plants. In field trials on selected plants (L. siceraria and A. esculentus), both biofertilizers showed significant increase in plant height, leaf length/width, fruit size and number of fruits per plant when compared with controls/untreated plants. Furthermore, plants co-inoculated with both the N fixing Azotobacter and phosphorus solubilizing A. niger have enhanced performance than those treated with each biofertilizer alone. Conclusion: The inoculation of seeds with A. niger and Azotobacter may replace costly and environment toxic chemical fertilizers with environment friendly and cost effective biofertilizers. Keywords: Biofertilizers, Azotobacter, A. niger, Bottle gourd and okr
Insights into Acute Myeloid Leukemia: Critical Analysis on its Wide Aspects
Acute myeloid leukaemia (AML) is a heterogeneous, most common type of acute leukaemia that involves mutation in haematopoietic and progenitors stem cells (HPSCs) leading to uncontrolled division, self-renewal and differentiation. Though it was untreatable about a half century ago, AML is now considered to be treatable in up to 40% of adults and those who are at or under 60 years of age. For the post-induction treatment, the mutation testing and cytogenetics are still an important prognostic tool. The AML treatment remains unchanged for almost three decades, although the field is advanced with the discovery of new drugs and deep understanding of the disease biology. Still, many people are relapsing and are dying eventually from the disease. This review discusses the broader aspects of AML, reflecting some of the most important and productive areas of research on the subject and was conducted using thoroughly searching databases, including Health Research and Development Information network Plus (HERDIN Plus), google scholar and PubMed to critically analyses the recent advances, available treatments and future prospectives of AML