485 research outputs found
Influence Of Non-Uniform Number Of Turns Per Coils And Stator Geometry On Unbalanced Magnetic Force In Brushless Permanent Magnet Machine
The Three Phase Permanent Magnet Brushless machines in which slot number and pole number combinations are similar such as differ by one have to be configured with asymmetric winding pattern in order to obtained perfect balanced back-emf among phases. However, the asymmetric winding pattern inherently results an unwanted force which is commonly known as an Unbalanced Magnetic Force or Unbalanced Magnetic Pull. An acoustic noise and vibration are the end results of this phenomenon. In some robotic application systems that require an accurate positioning control, this phenomenon is sometimes considerably severe. Investigations of electromagnetic performance in the asymmetric winding permanent magnet machines are carried out by using 2-D Finite-Element Analysis and the developed prototype machines are tested for verification purpose. In principle, the investigations are mainly driven by the efforts of minimizing the Unbalanced Magnetic Force. In this research, a reduction of Unbalanced Magnetic Force is achieved by implementing two approaches, i) non-uniform number of turns per coils in every tooth in a respective phase, and ii) an asymmetric design of stator. The investigation shows that only the first implementation technique is successful as reducing the existing Unbalanced Magnetic Force by 18% without damaging the desired torque performance in the subjected machines. Although the second implementation technique also could reduce the Unbalanced Magnetic Force, severe degradation of the torque performance as well as a bigger cogging torque existed. It is also shown that that the Unbalanced Magnetic Force is mostly influenced by it radial component instead of the tangential component. A reduction of radial force component result in a smaller Unbalanced Magnetic Force globally. Practically, the optimized design of machine is recommended for industrial applications which requires accurate position control such as robotic arm and conveying system
A Literature Review on Study of Silica fume as Partial Replacement of Cement in Concrete
In the recent past, there has been considerable attempts for improving the properties of concrete with respect to strength and durability, especially in aggressive environments. High performance concrete appears to be better choice for a strong and durable structure. A large amount of by-product or wastes such as fly-ash, copper slag, silica fume etc. are generated by industries, which causes environmental as well as health problems due to dumping and disposal.
Proper introduction of silica fume in concrete improves both the mechanical and durability characteristics of the concrete. This paper present literature review on replacement of Cement by Silica Fume which includes current and future trends of research
MPEG-4 video transmission using distributed TDMA MAC protocol over IEEE 802.15.4 wireless technology
The issues of green technology nowadays give an inspiration to the researcher to make all the future design to be energy efficient. Medium Access Control (MAC) layer is the most effective layer to provide energy efficient due to its ability to control the physical radio directly. One of the important applications in the future is a video transmission that can be transmitted with low-cost and low power consumption. MPEG-4 is one of the international standards for moving video. MPEG-4 provide better compression and primarily design at low bit rate communication. In order to achieve good quality for video application, the design at MAC layer must be strong. Therefore, to increase the performance of the MPEG-4 in IEEE 802.15.4, in this paper we propose a cross layer design between MAC layer and Application layer. A priority queue will be implemented at MAC scheduling depends on the level of frame important in MPEG-4 format frame. A distributed Time division Multiple Access (TDMA) will be used for MAC protocol to provide reliable data transmission for high priority frame
The delamination behaviour of Vectran/Epoxy composites having a novel non-crimp fabric architecture
The Mode I and Mode II Interlaminar Fracture Toughness (IFT) of Vectran/Epoxy composite material were investigated using the Double Cantilever Beam (DCB) and 4 End NotchedFlexure (4ENF) methods, respectively. Due to the relatively low compressive strength of Vectran material (<10% of its tensile properties), specimens were hybridised by overwrapping Vectran/Epoxy with T800s/M21 to prevent compressive failure during testing. Experimental results were then simulated using the non-linear Finite Element Method (FEM) package, LS-Dyna. Fractographic studies were also conducted to understand the mechanism of failure and factors influencing it
Key Features of SARS-CoV-2 and Available Therapies for COVID-19
The disease caused by severe acute respiratory syndrome (SARS-CoV2) is highly pathogenic and communicable infection, progressed in Wuhan city of China and then goes viral around the globe. The Genomic investigations exposed that Phylogenetically SARS-CoV2 resembles the other SARS-like bat viruses, therefore bats were also considered as the possible potential reservoir for SARS-CoV2. There are 2 prevalent types of SARS-CoV2, L type (~70%) and S type (~30%).The L strains are considered more infectious and virulent than the ancestral S strain. The positive sense single-stranded RNA genetic material contains 29891 nucleotides which codes for 9860 amino acids. The ORF1a/b is involved in carrying the translation of two (2) polyproteins, pp1a and pp1ab as well as the encoding of 16 NSPs (Non-structural proteins), and the leftover ORFS can bring about the encoding of non-essential and structural proteins. The origination source and transmission to humankinds is still not clear, but the intermediate hosts are supposed to have a significant role in the transfer and emergence of SARS-CoV2 from bats to humans. There is still no approved drug or vaccine available for Covid-19. In the current review, we condense and fairly evaluate the emergence and pathogenicity of SARS-CoV2, SARS-CoV and MERS-CoV. Moreover, we also discuss the treatment and vaccine developments strategies for Covid-19
Yield of esophagogastroduodenoscopy and colonoscopy in cancer of unknown primary
Objectives: Carcinoma of unknown primary origin (CUP) is heterogeneous group of cancers. Role of gastrointestinal (GI) endoscopy in this entity is under investigated. Aim of this study was to evaluate yield of Colonoscopy and Esophagogastroduodenoscopy (EGD) in localizing primary tumor in patients with CUP.
METHODOLOGY: Patients with histopathologically proven CUP who underwent colonoscopy / EGD to find the primary tumor from December 2009 to December 2011 were included in the study. Abdominal symptoms and cytokeratin (CK) 7 and 20 markers were correlated with presence of primary in GI tract.
Results: After giving informed consent 86 patients were included in final analysis. All patients underwent colonoscopy while 60(70%) got EGD along with colonoscopy. Mean age was 55.10 +/-11.94 years with 52(60%) male. Abdominal symptoms were present in 50%. CK7+/CK20- in 34(40%); CK7-/CK20+ in 2(2%) while CK7+/20+ in 7(8%) of metastatic tumor samples. Liver was metastatic site in 47(55%), Lymph node 12(14%) and Ascites in 8(9%). Endoscopy detected primary in 6 (7%) patients with 3 each in stomach and colon. No association of abdominal symptoms and cytokeratin markers was found with presence of GI primary site.
CONCLUSION: Yield of localizing primary lesion in the GI tract by pan-endoscopy was limited. Abdominal symptoms and cytokeratin markers do not predict presence of gastrointestinal malignancies
Effect of Monophasic Pulsed Current on Heel Pain and Functional Activities Caused by Plantar Fasciitis
Background: Plantar fasciitis (PF) is a soft tissue disorder considered to be one of the most common causes of inferior heel pain. The aim of this study was to investigate the effect of monophasic pulsed current (MPC) and MPC coupled with plantar fascia-specific stretching exercises (SE) on the treatment of PF.
Material and Methods: Forty-four participants (22 women and 22 men, with a mean age of 49 years) diagnosed with PF were randomly assigned to receive MPC (n=22) or MPC coupled with plantar fascia-specific SE (n=22). Prior to and after 4 weeks of treatment, participants underwent baseline evaluation; heel pain was evaluated using a visual analogue scale (VAS), heel tenderness threshold was quantified using a handheld pressure algometer (PA), and functional activities level was assessed using the Activities of Daily Living subscale of the Foot and Ankle Ability Measure (ADL/FAAM).
Results: Heel pain scores showed a significant reduction in both groups compared to baseline VAS scores (P
Conclusions: This trial showed that MPC is useful in treating inferior heel symptoms caused by PF
Towards prevention of sportsmen burnout : Formal analysis of sub-optimal tournament scheduling
Funding Statement: The authors are grateful to the Deanship of Scientific Research at King Saud University, Saudi Arabia for funding this work through the Vice Deanship of Scientific Research Chairs: Chair of Pervasive and Mobile Computing.Peer reviewedPublisher PD
Leveraging Large Language Models to Build and Execute Computational Workflows
The recent development of large language models (LLMs) with multi-billion
parameters, coupled with the creation of user-friendly application programming
interfaces (APIs), has paved the way for automatically generating and executing
code in response to straightforward human queries. This paper explores how
these emerging capabilities can be harnessed to facilitate complex scientific
workflows, eliminating the need for traditional coding methods. We present
initial findings from our attempt to integrate Phyloflow with OpenAI's
function-calling API, and outline a strategy for developing a comprehensive
workflow management system based on these concepts
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