228 research outputs found

    Joint design for shock mitigation

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    Smart projectiles carry various electronic components that can be damaged by severe shock loads. Propagation of shock from the region of initial loading to the locations of critical components can result in their failure. The objective of the research is to mitigate (absorb/reflect/disrupt, etc.) the incident shock loading, including simulating set-back, set-forward and balloting loads on a projectile as it exits the gun muzzle and predicting the structural response of internal electronic components. A detailed finite element analysis of the projectile and internal components is presented. The effect of electronic component mounting location on peak acceleration and RMS acceleration has been studied

    Coal hydrotreatment with coal-derived solvents to produce carbon product precursors

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    It is known that many specialty carbon products can be produced from coal. Direct liquefaction (hydrotreatment) is one of the most promising processes for coal conversion. In this present work, liquefaction of Marfork coal was examined at 350°C, 400°C and 450°C and an initial pressure of 500 psig of Nitrogen or Hydrogen using coal-derived solvents Carbon Black Base (CBB) and Heavy Creosote Oil (HCO) and their hydrogenated forms. Unlike model solvents such as Tetralin, coal-derived solvents are cheaper, readily available and recoverable. The solvents were first hydrogenated using unconverted residue from coal hydrotreatment and NiO/MoO3 on alumina as catalysts. Coal hydrotreatment experiments were conducted to determine the effectiveness of the solvents as hydrogen donors. The products obtained are exhaustively extracted in Tetrahydrofuran (THF), filtered to separate THF insolubles (unconverted coal), and after THF removal, vacuum distilled to separate pitch material (distillation bottom) and recycle solvent (overhead). It was observed that the coal conversion increased when hydrogenated solvent was used. (Abstract shortened by UMI.)

    FPGA Implementation of Low Power Serial to High Speed Data Networks

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    FPGA based solutions become more common in embedded systems these days. These systems need to communicate with external world. Considering high-speed and popularity of Ethernet communication, developing a reliable real-time Ethernet component inside FPGA is of special value. To that end, we present a new solution for FPGA Gigabit Ethernet communications with timing analysis. The solution deals with "Gigabit Media-Independent Interface" in its physical layer. Network protocol is implemented from physical to transport layer which is UDP. In this Project using LAN connection various data will be captured by FPGA and will be sent on a serial line. Read the data from UART Receive and transform the data in it. On FPGA logic is implemented to read data from serial port. Write data in to memory location and transmitted data out put The FPGA module takes data from serial port and sends to PC in Ethernet form. In PC application will be developed to read data from Ethernet

    STUDY OF KNOWLEDGE, ATTITUDE, AND PRACTICE OF GENERAL POPULATION OF GUNTUR TOWARD SILENT KILLER DISEASES: HYPERTENSION AND DIABETES

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    ABSTRACTObjectives: The objective was to study the demographic details of hypertensive and diabetic patients and their knowledge, attitude, and practices(KAP) regarding their illness.Methods: We examined KAP on hypertension and diabetes in a sample of 50 adult hypertensive patients and 50 adult diabetic patients aged above20 years. KAP's were assessed during the period from October 2014 to January 2015.Results: Altogether 50 hypertensive and 50 diabetic patients were enrolled in the study. Most of the respondents in the KAP on hypertension wereaged between 31and 40 years (56%) and 94% of the participants knew that hypertension is the disease state whereas in KAP on diabetes 46% areaged in between 31 and 40 years of age, 88% of participants know that the diabetes is a condition in which the body contains increased levels of bloodglucose. We observed poor score in attitude and practice part of the questionnaire. It concludes that the responders had good knowledge but poorattitude and practice toward the diseases. Repeated reinforcement and motivation along with health education will definitely bring about a positivechange in attitude and practices among the patients.Conclusion: We conclude that the motivation and counseling stressing the importance of lifestyle modifications and self-management is required forthe patients suffering with chronic diseases such as hypertension and diabetes. Patient counseling by the clinical pharmacist can play a vital role inimparting education to the diabetic and hypertensive patients.Keywords: Hypertension, Diabetes, Knowledge, Attitude, Practices

    An Unusual Presentation of Immunoglobulin G4-Related Disease (IgG4-RD) Causing Subglottic Stenosis

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    Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory condition that is known to involve multiple organs and was first described as an entity in 2003. It is characterized by lesions with a dense lymphoplasmacytic infiltrate, IgG4-positive plasma cells, storiform fibrosis, and frequently elevated serum IgG4 levels. Organs that are commonly involved include the pancreas, biliary tree, salivary glands, periorbital tissues, kidneys, retroperitoneum, lungs, pleura, thyroid, aorta, and lymph nodes. Rarer manifestations of IgG4-RD include central nervous system (CNS) involvement, prostatitis, mastitis, midline destructive disease, and nasopharyngeal disease. In this report, we discuss an atypical case of a young woman with laryngeal subglottic involvement leading to stenosis and airway obstruction, which was ultimately successfully managed with systemic immunosuppression

    Neural Networks for Constitutive Modeling -- From Universal Function Approximators to Advanced Models and the Integration of Physics

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    Analyzing and modeling the constitutive behavior of materials is a core area in materials sciences and a prerequisite for conducting numerical simulations in which the material behavior plays a central role. Constitutive models have been developed since the beginning of the 19th century and are still under constant development. Besides physics-motivated and phenomenological models, during the last decades, the field of constitutive modeling was enriched by the development of machine learning-based constitutive models, especially by using neural networks. The latter is the focus of the present review, which aims to give an overview of neural networks-based constitutive models from a methodical perspective. The review summarizes and compares numerous conceptually different neural networks-based approaches for constitutive modeling including neural networks used as universal function approximators, advanced neural network models and neural network approaches with integrated physical knowledge. The upcoming of these methods is in-turn closely related to advances in the area of computer sciences, what further adds a chronological aspect to this review. We conclude this review paper with important challenges in the field of learning constitutive relations that need to be tackled in the near future

    ANTI-INFLAMMATORY, CYTOTOXIC AND ANTIOXIDANT EFFECTS OF METHANOLIC EXTRACTS OF DRYPETES SEPIARIA (EUPHORBIACEAE)

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    Abstract The aim of this study was to investigate in vitro antioxidant, anti-inflammatory and cytotoxic activities of the petroleum ether, ethyl acetate, methanol and aqueous extracts obtained from leaves of Drypetes sepiaria (Euphorbiaceae). Total phenolic and flavonoid contents of these crude extracts were determined as gallic acid and quercetin equivalents, respectively. In in vitro antioxidant method, methanol extract exhibited higher free radical scavenging activity compared to standard compound, ascorbic acid with IC 50 of 95.43µg/ml (DPPH) and 67.05µg/ml (ABTS). Methanol extract was able to inhibit inflammation by in vitro about 85-90% (HRBC stabilization method) and in vivo about 40-45% (Paw oedema method) anti-inflammatory assays compared to standard produced 50.04% at 6h period. In cytotoxicity assay (MTT assay) methanolic extract exhibited IC 50 of 10µg/ml. In apoptosis (flow cytometric assay), the control group showed normal caspase 3 activity in the SiHa cells which was 0.24%, and increased up to 40% after treatment

    ANTI-INFLAMMATORY, CYTOTOXIC AND ANTIOXIDANT EFFECTS OF METHANOLIC EXTRACTS OF DRYPETES SEPIARIA (EUPHORBIACEAE)

    Get PDF
    The aim of this study was to investigate in vitro anti-oxidant, anti-inflammatory and cytotoxic activities of the petroleum ether, ethyl acetate, methanol and aqueous extracts obtained from leaves of Drypetes sepiaria (Euphorbiaceae). Total phenolic and flavonoid contents of these crude extracts were determined as gallic acid and quercetin equivalents, respectively. In in vitro antioxidant method methanol extract exhibited higher free radical scavenging activity compared to standard compound, ascorbic acid with IC50 of 95.43µg/ml (DPPH) and 67.05µg/ml (ABTS). Methanol extract was able to inhibit inflammation by in vitro about 85-90% (HRBC stabilization method) and in vivo about 40-45% (Paw edema method) anti-inflammatory assays compared to standard produced 50.04% at 6h period. In cytotoxicity assay (MTT assay) methanolic extract exhibited IC50 of 10µg/ml. In apoptosis (flow cytometric assay), the control group showed normal caspase 3 activity in the SiHa cells which was 0.24% and increased up to 40% after treatment
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