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31.
Multipath transport protocols like Stream Control Transmission Protocol (SCTP) and Multipath TCP (MPTCP) have been introduced in the past as alternatives to traditional single path transport protocols like TCP and UDP. Various approaches to divide the flow on multiple paths have also been proposed in the literature. In this work, we show that the bandwidth estimation based resource pooling (BERP) congestion control algorithm is a practical implementation of the Min–Max optimization approach for flow division and verify this through ns-2 based simulations.  相似文献   
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The dynamic behavior of hydraulic gates needs to be determined for design purposes. This is a difficult task because the interaction between fluid and gate can significantly affect the response of the structure and hence has to be properly taken into account in the analysis. The goal of the present work is to use a velocity potential-based finite element formulation and a hydraulic model test for dynamic analysis of a radial gate–fluid system. The problem is solved using the displacement and velocity potential as the variables in the solid and fluid domain, respectively.  相似文献   
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Wireless Personal Communications - The potential of polylactic acid (PLA) material as an ultra-wide band (UWB)-dielectric resonator antenna (DRA) created by 3D-printing technique are described in...  相似文献   
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Information technology companies have grown in size and recognized the need to protect their valuable assets. As a result, each IT application has its authentication mechanism, and an employee needs a username and password. As the number of applications increased, as a result, it became increasingly complex to manage all identities like the number of usernames and passwords of an employee. All identities had to be retrieved by users. Both the identities and the access rights associated with those identities had to be protected by an administrator. Management couldn’t even capture such access rights because they couldn’t verify things like privacy and security. Identity management can help solve this problem. The concept behind identity management is to centralize identity management and manage access identity centrally rather than multiple applications with their authentication and authorization mechanisms. In this research work, we develop governance and an identity management framework for information and technology infrastructures with privileged access management, consisting of cybersecurity policies and strategies. The results show the efficiency of the framework compared to the existing information security components. The integrated identity and access management and privileged access management enable organizations to respond to incidents and facilitate compliance. It can automate use cases that manage privileged accounts in the real world.  相似文献   
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The global energy consumption is increasing day by day. This increased energy demand can only be fulfilled through large-scale renewable energy integration. This article presents the mathematical modeling, control, and integration of a bio-fuel prime mover fed self-excited induction generator (SEIG) for medium voltage direct current (MVDC) ship power system. A three-phase current controlled voltage source inverter (VSI) working as a static synchronous compensator (STATCOM) injects compensating currents at the point of common coupling (PCC) for harmonic elimination and regulation of the generated voltage under varying load. The VSI is connected at the PCC through a three-phase zig-zag/star transformer which reduces the voltage stress at the DC link. An indirect current technique based controller is used to generate gating pulses for the STATCOM. The MVDC load zone is modeled as an integral sliding mode controlled DC-DC converter feeding ship service loads in shipboard system. Hardware realization of the proposed system has been implemented with 3.7kW induction generator.  相似文献   
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Iron oxide (Fe2O3) nanoparticles are widely used in different fields of nanotechnology. However, studies on its toxicological effects in humans and the environment are scarce. Therefore in this investigation 28 days repeated dose oral toxicity studies were conducted on Fe2O3-30 nanoparticles and its counterpart Fe2O3-Bulk with special reference to target biochemical enzymes and histopathological changes in different tissues of female albino Wistar rats. The alterations observed after Fe2O3-30 treatment in various tissues of exposed rats were dose dependent. Low dose was less effective than medium and high doses with low dose demonstrating "no observed adverse effect" (NOAEL). Further, high dose treated rats showed toxic sign and symptoms but no mortality. Due to the repeated doses of Fe2O3-30 nanoparticles, significant inhibition was observed in total, Na(+)-K+, Mg2+ and Ca(2+)-ATPases in brain of exposed rats. Similarly, significant inhibition was recorded in RBC and brain acetylcholinesterase indicating that both synaptic transmission and nerve conduction were affected by this compound. Fe2O3-30 significantly increased aspartate amino transferase, alanine amino transferase and lactate dehydrogenase in serum and liver, whereas, these enzymes were significantly decreased in kidney indicating tissue necrosis and possible leakage of these enzymes into the blood stream. Increased levels of these enzymes in liver as well as in serum might be an adaptive mechanism due to the stress of iron nanoparticles. High dose treated rats of Fe2O3-30 showed dilated central vein, perivascular round cell collections in liver along with focal areas of necrosis, whereas kidney showed focal tubular damage and red pulp congestion, whereas prominent white pulp indices were observed in spleen. However, histopathological analysis of heart and brain tissues failed to show any adverse changes in their architecture exposed to repeated doses of Fe2O3-30 when compared with controls. Fe2O3-Bulk did not induce any adverse effects in either biochemical parameters or histopathology in the treated rats and the changes observed were near to controls and mostly insignificant, indicating that the counter part of nanoparticles i.e., bulk material is less potent than the nanoparticles in causing toxicity in the exposed animals. These results suggested that as particle size decreases, this iron nanoparticle showed increased toxicity, even though the same material is relatively inert in bulk form. The changes observed in these target enzyme activities could be useful as biomarkers of exposure to nanoparticles.  相似文献   
38.
Singh  Jeetendra  Singh  Shailendra  Paras  Neha 《SILICON》2023,15(2):783-792
Silicon - This paper deals the hybridization of tunnel FET with the memristor for better execution of combinational and sequential circuits. Here, device structure of vertical tunnel FET and...  相似文献   
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We report on the use and stability of solution‐processed molybdenum oxide (sMoOx) thin films as anode‐modifying layers to replace conventionally used poly(3,4‐ethyldioxythiophene)/poly(styrenesulfonate) (PEDOT/PSS) layers in poly(3‐hexylthiophene):[6,6]‐phenyl C61 butyric acid methyl ester (P3HT/PC61BM) bulk heterojunction organic solar cells. Our results show that while as prepared devices using the two anode‐modifying layers possess similar performances, the sMoOx devices exhibit a staggering 20‐fold stability improvement in its performance half‐life compared with PEDOT/PSS devices, ~3400 h versus ~150 h, respectively. A further comparison of the stability between encapsulated and unencapsulated devices demonstrates the necessity for protection from atmospheric moisture and oxygen but again highlights the lucrative nature of sMoOx as a protective anode‐modifying layer compared with PEDOT/PSS even under ambient conditions. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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