Design and Fabrication of Shock Absorber Compressor Spring

This report contains the design, fabrication and performance analysis of a shock absorber spring compressor. The detailed data of the different parts was presented. The materials selected for each part, the reason for selecting that material and the design of the different parts of the shock absorber compressor spring was carried out. The manufacturing processes involved was presented. From the design it was established that deflection in the spring decreases with reduction in the stresses applied to the spring. The test result of the fabricated shock absorber compressor spring shows that the tool was very efficient in extracting the spring during the repair process with danger of harming the technician working with the tool

Performance Evaluation Engine of Sensors in Automobile System

The number of automobile sensors is increasing continuously because of their proved benefits represented in avoided accidents, higher driving efficiencies, and ubiquitous sensing-based services. These benefits are not limited to only the vehicle’s driver, but also to other vehicles and third parties. Sensors also control vehicle emissions and make vehicles more comfortable and efficient. In this article, we categorized different types of sensors and their function. We also developed a concept that shows how automobile equipped with sensors can be considered as essential mobile resource of sensory data and sensor-related application. In addition, we categorize automobile sensors along the area that support ITS application and communication technologies. The responses of these sensors in an automobile has resulted in high efficacy in the area of safety, movement and environment. Each sensor is activated by the Electronic Control Unit when it receives an electrical signal between 2- 5V and send information to the actuators that performs work. Results obtained have shown increased performance in the response time to activities of the driver while driving

Performance of Fuel Electronic Injection Engine Systems

Electronic Fuel Injection systems are very important components in today’s automotive industry. Its use on modern engines allows manufactures to develop new engine designs while increasing engine efficiency and lowering fuel consumption and exhaust gas emissions. EFI systems also increased engine reliability by providing a smooth start and run under most weather conditions. This paper presents the state-of-the-art of direct fuel injection in spark-ignition (SI) engines, the current technology to make possible its accomplishment, the characteristics of the engines using this system and a comparative experimental study between this system

Cellular responses to modified Plasmodium falciparum MSP119 antigens in individuals previously exposed to natural malaria infection

<p>Abstract</p> <p>Background</p> <p>MSP1 processing-inhibitory antibodies bind to epitopes on the 19 kDa C-terminal region of the <it>Plasmodium falciparum </it>merozoite surface protein 1 (MSP1₁₉), inhibiting erythrocyte invasion. Blocking antibodies also bind to this antigen but prevent inhibitory antibodies binding, allowing invasion to proceed. Recombinant MSP1₁₉had been modified previously to allow inhibitory but not blocking antibodies to continue to bind. Immunization with these modified proteins, therefore, has the potential to induce more effective protective antibodies. However, it was unclear whether the modification of MSP1₁₉would affect critical T-cell responses to epitopes in this antigen.</p> <p>Methods</p> <p>The cellular responses to wild-type MSP1₁₉and a panel of modified MSP1₁₉antigens were measured using an <it>in-vitro </it>assay for two groups of individuals: the first were malaria-naïve and the second had been naturally exposed to <it>Plasmodium falciparum </it>infection. The cellular responses to the modified proteins were examined using cells from malaria-exposed infants and adults.</p> <p>Results</p> <p>Interestingly, stimulation indices (SI) for responses induced by some of the modified proteins were at least two-fold higher than those elicited by the wild-type MSP1₁₉. A protein with four amino acid substitutions (Glu27→Tyr, Leu31→Arg, Tyr34→Ser and Glu43→Leu) had the highest stimulation index (SI up to 360) and induced large responses in 64% of the samples that had significant cellular responses to the modified proteins.</p> <p>Conclusion</p> <p>This study suggests that specific MSP1₁₉variants that have been engineered to improve their antigenicity for inhibitory antibodies, retain T-cell epitopes and the ability to induce cellular responses. These proteins are candidates for the development of MSP1-based malaria vaccines.</p

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

Structural Damage Detection in Beams by Wavelet Transforms

The use of a laser-based optical system and wavelet transforms is explored for the detection of changes in the properties of cantilevered aluminum beams as a result of damage. The beams were modeled using the ANSYS 5.3 finite-element method and the first six mode shapes for the damaged and the undamaged cases obtained. Damage was simulated by a reduction in the stiffness of one element. Gaussian white noise was added externally to simulate field conditions. The results show that a spatially-localized abnormality in the mode shape could be represented uniquely by a small set of wavelet coefficients while the white noise was uniformly spread throughout the wavelet space. It was observed that the damage clearly manifested in the sixth-order detail of certain modes only. A different finite-element model was used as a test beam to validate the proposed method. An actual aluminum beam, fabricated with dimensions similar to the test beam, was excited and the mode shapes recorded with the scanning laser vibrometer. Damage was created by machining a notch in the beam of the same dimensions as the finite-element test beam. An image of the damage location was obtained from the continuous wavelet transform coefficients. The magnitude of the wavelet coefficients at the damage location showed a close correlation to the severity of damage. It was observed to increase with increasing damage. The finite-element test beam results showed a close correlation to the corresponding experimental beam results. The method benefits from the fact that the undamaged mode shapes were not used to evaluate the condition of the beam, which in most field conditions is not feasible

Enhancement of Viscosity and Thermal Conductivity of Soybean Vegetable Oil using Nanoparticles to Form Nanofluids for Minimum Quantity Lubrication Machining of Difficult-To-Cut Metals

Sustainable use of vegetable oil as a base fluid in minimum quantity lubrication (MQL) strategy for machining advanced materials is promising but limited due to their low thermal conductivity and viscosity. This paper presents the results of experimental investigation for enhancing viscosity and thermal conductivity of high oleic soybean vegetable oil (HOSO) using Al2O3, MoS2, and TiO2 nanoparticles (30 nm particle size and 0.5-4.0% wt. concentration) inclusion to form nanofluids at temperature ranging from 25 to 70 °C for use in vegetable oil-based nanofluids-MQL machining of difficult-to-cut metals. The result shows that viscosity and thermal conductivity of HOSO increase with increase in nanoparticle weight concentration, but there is a decrease in suspension stability of the nanofluid. Also, viscosity of HOSO nanofluids decreases with increase in temperature, but thermal conductivity increases with increase in temperature, while for the base HOSO, it decreases with increase in temperature. This is a very significant positive observation especially for difficult-to-cut materials that generate high heat that need to be conducted away from the cutting zone. Thermal conductivity and viscosity were enhanced up to 55% (using MoS2 at 70 °C and 4% wt. concentration) and 11.5% (using TiO2 at 50 °C and 3.5% wt. concentration), respectively. The Brownian motion of the nanoparticles and liquid-solid interlayer interfaces are responsible for this behavior of the nanofluid thermal conductivity, while nanoparticle thickening and entangle mechanism were responsible for the behavior of the nanofluid viscosity. This implies that lower oil flow rate can be applied during machining of Inconel-718 due to increased viscosity and thermal conductivity to obtain optimal machining performance, lower power consumption, and reduce negative impact on the environment

Machinability Characterization in Drilling Graphite Fiber-Composites

Due to the inhomogeneous nature of the composite materials, the machinability of fiber reinforced composites is different from that of metals. In this paper, a method for characterization of the machinability of composite materials is presented. This method is based on parametric analysis of the drilling process using the Design of Experiments Approach. The project goal includes quantifying the effects of cutting speed, feed rate, tool material, and tool geometry on delamination, surface roughness, and thrust force during the drilling of carbon fiber-reinforced composites. Utilizing the aforementioned method, the optimum machinability characteristics of graphite fiber reinforced composites were predicted with 97% accuracy

Machinability Characterization in Drilling Graphite Fiber-Reinforced Composites

Due to the inhomogeneous nature of the composite materials, the machinability of fiber reinforced composites is different from that of metals. In this paper, a method for characterization of the machinability of composite materials is presented. This method is based on parametric analysis of the drilling process using the Design of Experiments Approach. The project goal includes quantifying the effects of cutting speed, feed rate, tool material, and tool geometry on delamination, surface roughness, and thrust force during the drilling of carbon fiber-reinforced composites. Utilizing the aforementioned method, the optimum machinability characteristics of graphite fiber reinforced composites were predicted with 97% accuracy