25 research outputs found

    Tyre-road adherence conditions estimation for intelligent vehicle safety applications

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    It is well recognized in the automotive research community that knowledge of the real-time tyre-road friction conditions can be extremely valuable for intelligent safety applications, including design of braking, traction, and stability control systems. This paper presents a new development of an on-line tyre-road adherence estimation methodology and its implementation using both Burckhardt and LuGre tyre-road friction models. The proposed strategy first employs the recursive least squares to identify the linear parameterization (LP) form of Burckhardt model. The identified parameters provide through a Takagi-Sugeno (T-S) fuzzy system the initial values for the LuGre model. Then, it is presented a new large-scale optimization based estimation algorithm using the steady state solution of the partial differential equation (PDE) form of LuGre to obtain its parameters. Finally, real-time simulations in various conditions are provided to demonstrate the efficacy of the algorithm

    Metabolic Modeling-Based Drug Repurposing in Statin: An Overview of Mechanistic Approaches in the Management of Craniocerebral Trauma

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    Drug repurposing, known as drug repositioning, is considered a method for redeveloping a compound to utilize in a distinctive illness, which is now becoming a progressively critical procedure for industrial researchers and the scholarly community. A large number of repurposed medicines have been discovered by chance in the lab or through the careful monitoring of drug action in the clinic and retrospective analysis of clinical findings. Additionally, statins are broadly used to treat hyperlipidemia and prevent cardiovascular disease although their application as the neuroprotective agents weakening secondary neurological harm is yet limited in traumatic brain injury (TBI). Their other non-cholesterol-mediated (i.e., pleiotropic) mechanisms of action include upregulating endothelial nitric oxide synthase expression, and enhancing neurogenesis and synaptogenesis, as well as anti-apoptotic effects, increased angiogenesis, and various antioxidant and anti-inflammatory mechanisms. Almost all studies have supported the potential role of statins in neuroprotection, and a few have particularly focused on their effects in traumatic brain injury models. The sulfonylurea receptor 1 (SUR1) protein is a regulatory component linked with pore-forming ion channels. Thus, ATP-sensitive potassium (KATP) channels are created, which can be demonstrated in pancreatic islet cells and certain neurons. Further, transient receptor potential melastatin 4 (TRPM4) is the second pore-forming subunit of SUR1. Upregulating SUR1 and opening SUR1-TRPM4 opening have been observed in the different models related to central nervous system (CNS) injuries such as TBI. Sulfonylurea drugs may prevent neuronal degeneration and improve post-TBI cognitive results by inhibiting the SUR1-TRPM4 channel

    Evaluation of the Effects of Melatonin Supplementation on Coagulation in Patients with Haemorrhagic Stroke; A Randomized, Double-Blind, Controlled Trial

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    Introduction: Considering that hemorrhagic stroke patients are at higher risk for bleeding, administration of higher doses of melatonin with a controversial coagulation profile is a serious concern. Objective: This study aimed to investigate the possible effects of high doses of melatonin on bleeding parameters and blood hemostasis in hemorrhagic stroke patients. Methods: This study is a randomized, double-blind, prospective, controlled trial. Confirmed hemorrhagic stroke patients were divided into two groups. Participants were randomly assigned into the melatonin group (30 mg daily via gastric tube gavage for 5 consecutive days) or the control group. Each patient was monitored for 5 days, and 2 blood samples were taken and the effect of the intervention on coagulation factors and blood hemostasis were investigated. Result: In total, 30 patients were randomly assigned to melatonin (n=15) or control groups (n=15). there was no significant difference between the two groups in demographic and clinical characteristics. There was a significant decline in prothrombin time (PT) and fibrinogen levels in the melatonin group (p=0.011 & p<0.001, respectively). P-values for VII and VWB factors showed a significant increment in these two factors in the melatonin group after the intervention (p=0.035 & p=0.002, respectively). No significant changes in serum levels of D-dimer factor, APACHE II, and GCS scores were evident in the two groups after the intervention (p>0.05). Conclusion: Considering the favorable changes in coagulation parameters observed in this study, it could be concluded that melatonin can have both procoagulant and antithrombin properties

    Visible light mediated photocatalytic anionic and cationic dyes degradation using ZnO-Fe2O3 nanocomposite

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    In this work, hydrothermal technique and precursor materials obtained from the wastes of filtration unit of gas pressure reduction station were used to create ZnO-Fe2O3 nanocomposite. FT-IR, FE-SEM, XRD and TEM analyzes were used to investigate the properties of the produced nanocomposite. XRD analysis showed the structure of ZnO and Fe2O3 without impurities. The crystal size of ZnO-Fe2O3 nanocomposite was determined to be about 53 nm. FE-SEM images showed a nanocomposite pattern with an approximate diameter of 50 nm. Finally, visual decomposition of anionic and cationic dyes under visible light was used to study the photocatalytic activity of ZnO-Fe2O3 nanocomposite. By exposing a metal halide lamp to light and darkness for 60 minutes and 150 minutes, respectively, it was possible to study the photocatalytic activity of the synthesized nanocomposite in removing anionic and cationic dyes from aqueous medium. In the photocatalytic degradation of anionic and cationic dyes, the following factors were considered as essential variables: pH, initial dye concentration, nanocomposite content and exposure time. In this study, the degradation percentage of anionic and cationic dyes of ZnO-Fe2O3 nanocomposite with a ratio of 0.75:1 was 99.89 and 99.9%, respectively. The amount of band gap was calculated by Tack plot method and electrical conductivity was calculated using electrochemical impedance spectroscopy, which reduced the band gap. And the resistance increases. Due to the acceleration of charge transfer at the heterogeneous junction surface and the suppression of electron/hole pairs from recombination, the ZnO-Fe2O3 nanocomposite significantly increased the visible light current response

    The role of magnesium sulfate in the intensive care unit

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    Magnesium (Mg) has been developed as a drug with various clinical uses. Mg is a key cation in physiological processes, and the homeostasis of this cation is crucial for the normal function of body organs. Magnesium sulfate (MgSO4) is a mineral pharmaceutical preparation of magnesium that is used as a neuroprotective agent. One rationale for the frequent use of MgSO4 in critical care is the high incidence of hypomagnesaemia in intensive care unit (ICU) patients. Correction of hypomagnesaemia along with the neuroprotective properties of MgSO4 has generated a wide application for MgSO4 in ICU

    Recent Silicon Valley SSCS Chapter Activities: Talks, Seminars, Workshops, and DLs [Chapters]

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    REAL TIME IDENTIFICATION OF AUTOMOTIVE DRY CLUTCH FRICTIONAL CHARACTERISTICS USING TRUST REGION METHODS

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    Real-time knowledge of the variable characteristics in dry-clutch subsystems is crucial for understanding the dynamic behaviour of an automotive dry-clutch system. The automotive dry-clutch system plays a key role in passenger car gearboxes based on automated manual transmissions as well as in broader class of vehicle driveline systems. Thus, in order to have a good performance of vehicle longitudinal dynamics, whose response is strongly related to the effectiveness of the control strategy, real-time estimation of the dry-clutch torque transmission characteristics is required.This paper presents an original development of an on-line torque transmission model characteristics estimation methodology along with ability of vehicle powertrain dynamics consideration. The method focused to provide the direct capability to observe the kiss-point value by using measurable signals in real-time. Real-time simulations in various conditions demonstrate the effectiveness of the algorithm. Very promising results are expected in different scenarios

    Vehicle Tyre/Road Interaction Modeling and Identification of its Parameters Using Real-Time Trust-Region Methods

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    Driving safety can be achieved by better understanding critical situations which may require the knowledge of interaction between vehicle tyres and the road surfaces. It is thus essential to have a good estimation of the tyre/road friction parameters in real-time. The paper deals with the trust-region based method for on-line estimation of tyre/road friction parameters. This method provides an appropriate modeling (of a vehicle and the tyre/road contact) to observe the tyre/road friction coefficients directly using measurable signals in real-time. In this work, we present a new LuGre model-based nonlinear least squares (NLLS) parameter estimation algorithm using vehicle dynamic to obtain the parameters of LuGre model based on recursive nonlinear optimization of the curve fitting errors. The proposed estimation method can also be utilized in large-scale problems with similar conditions. Very promising. results have been obtained in real-time simulations for most of the driving and road situations

    Joint structure for the real-time estimation and control of automotive dry clutch engagement

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    In this paper, real-time identification of the dry-clutch torque characteristics model in automotive systems is investigated. The proposed algorithm focused to provide the direct capability to update the clutch torque characteristics model by using engine speed and torque as measurable signals in real-time, within a multiple model predictive control loop. First, the clutch torque is estimated with some uncertainty. Then, it is proposed a new trust-region based identification approach which is robust enough to cover this uncertainty. The aim of the MPC controller is to ensure a comfortable lockup by avoiding engine stall and reasonable engagement time. The effectiveness and performance of the approach are demonstrated through the real-time model simulations in various conditions
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