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A New Approach in Design of a Pavement Reinforced by A Geosynthetic Layer in Severely Stressed Area of the Airport Pavement to Accommodate Stresses Imposed by Aircraft Landing and Ground Movements

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Journal of Transportation Technologies 2022年第3期12卷 346-356页

作者： devinder kumar yadav School of Aerospace University of Nottingham Ningbo China Ningbo China

Pavements of airport runway and apron are subjected to stern stresses imposed by landing and ground movements of aircraft. The stresses are primarily concentrated in touchdown zone and wheel path areas of the pavement structure. This paper proposes that this area can be designed using geosynthetic layer reinforcement to minimise deflection and deterioration of the structure. The reinforcement can reduce the vertical stresses on the underground fuel pipes in the apron area, if used. The concept of ditch conduit reinforcement is suggested where a geosynthetic layer is used within a soil backfill to redistribute load over a conduit leading to stress redistribution. It is observed that the vertical load is significantly reduced by the arching action of the soil mass overlying the conduit. The load can be reduced further by placing a geosynthetic reinforcement layer within the soil backfill above the conduit. It is suggested that the inclusion of a geosynthetic layer in the granular backfill reduces the vertical load on a ditch conduit and the amount of reduction depends upon the tensile modulus, deflection of the geosynthetic and soil arching action. This leads to believe that a reinforced pavement structure for runway and aerodrome apron area improves the load carrying capacity of the pavement to sustain the operations of heavy transport aircraft, including occasional overloading of the pavement. Hence, this paper explores a possibility of using a geosynthetic layer under the runway pavement to provide reinforcement.

关键词： Aircraft Airport Aeronautical Aviation Apron Engineering Pavement Runway Structure

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A Comparative Study of Managing a Project Using Traditional Management Techniques and a Critical Chain Project Management Methodology in Aircraft Maintenance Field

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Journal of Transportation Technologies 2022年第4期12卷 544-558页

作者： devinder kumar yadav Anand Kulkarni Hui Yao University of Nottingham Ningbo China Ningbo China Department of Management National University of Singapore Queenstown Singapore Ningbo DEKO Information Technology Company Limited Ningbo China

Aircraft on ground or down-time for its maintenance is a clear loss in revenue for an airline operation. With never ending competition and growing operating costs of aircraft, airlines continuously need to explore opportunities to reduce the aircraft down-time in order to remain sustainable. Due to round the clock operation feature of scheduled airlines, aircraft maintenance operations are generally carried out using traditional management methodologies instead of considering it as a project. Though aircraft heavy maintenance checks consist of several major tasks that can last from few weeks to a year, the maintenance organisations do not adopt modern project management methodologies. Therefore, this paper models a heavy maintenance check of an Airbus aircraft as a typical project and adopts contemporary project management methodology to explore the possibility of reducing the downtime. To this end, a case study has been done at an aircraft maintenance company to analyse the potential of this project management method in aircraft maintenance industry.

关键词： Aviation Airline Aircraft Engineering Management Maintenance Operations Planning Project

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Selection and Impact of an Aerofoil Leading Edge on Boundary Layer Transition

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Journal of Transportation Technologies 2022年第4期12卷 778-803页

作者： Dinesh Bhatia devinder kumar yadav Guangjun Yang Jian Wang Henrik Hesse School of Aerospace Engineering University of Glasgow Glasgow Singapore School of Aerospace University of Nottingham Ningbo China Ningbo China School of Aeronautics Northwestern Polytechnical University Xi’an China Faculty of Science Engineering and Computing Kingston University London UK

The choice of leading-edge aspect ratio (AR) plays a crucial role when planning boundary layer wind tunnel tests on a flat plate. Poor selection of the leading-edge profile hampers effectiveness of the experiment and increases testing costs associated with interchanging of leading edges to attain accurate results. Thus, the appropriate selection of the leading edge is a very crucial part of the wind tunnel experiment process. It is argued that the curvature of the leading edge and thus the AR is of paramount importance to achieve accurate results from the wind tunnel testing. In this project, seven different elliptical leading edges were tested, and their performance was compared with an ideal leading edge with zero thickness. Experiments and computation have been done for leading edges ranging from AR6 to AR20. Results were evaluated for boundary layer transition onset location, and it was found that AR20 has the least influence on the flow structure when compared to the ideal leading edge. A study of the flow structure at the stagnation point indicates an increase in adverse pressure gradient with an increase in the AR but also shows a decrease in the size of the stagnation region. The presence of a higher AR leading edge reduces the turbulent spot production rate, which is one of the primary causes of boundary layer transition. This paper presents a correlation that enables aerodynamicists to quantify the impact of the leading-edge AR on transition. A typical case is also presented to compare the relative performance of a wedge and the higher AR leading edge, which provides a choice between an elliptical or a wedge-shaped leading edge.

关键词： Boundary Layer Transition Leading Edge Aspect Ratio Curvature Flow Structure Adverse Pressure Gradient

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Contrastive Analysis of Distractions to Pilot Caused by Various Flight Instrument Displays

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Journal of Transportation Technologies 2022年第2期12卷 209-227页

作者： devinder kumar yadav Yingxue Zhao Chunyi Gao Yufei Wang Tianzuo Dong Dinesh Bhatia University of Nottingham Ningbo Ningbo China University of Glasgow Singapore Singapore

Automation of aircraft instrument displays enhances flight safety, but it also increases complexity and pilot workload. Executing changes in flight plan, navigation or communication during flight using flight instrument switches often increases pilots’ workload and this may also cause distraction that adds potential risks to flight safety. This study compares the conventional avionics panel and touchscreen avionic panel to find out the least distractive panel for the pilots. Thirty simulated flights using four different pilots were carried out;and aircraft speed, altitude and heading parameters using both avionics systems were observed to study the operational efficiency and pilot distraction resulted from each of the avionic systems. The distraction was examined by a parameter analysis based on the Mean Squared Error (MSE) mathematical model and visually by recording videos of each simulated flight. The results indicate that the touchscreen system is more efficient and less erroneous for the aircraft in maintaining the parameters as compared with the conventional system. There is also a clear relationship between task completion time and disruption level on the parameters control.

关键词： Aviation Touchscreen Safety Conventional Cockpit Simulate Flight

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Role of diet in the management of inflammatory bowel disease

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World Journal of Gastroenterology 2010年第12期16卷 1442-1448页

作者： Nirooshun Rajendran devinder kumar Department of General Surgery 3rd FloorSt James WingSt George's Hospital

Many studies have looked at connections between diet,etiology,signs and symptoms associated with inflammatory bowel disease(IBD).Although these connections are apparent to clinicians,they are difficult to prove qualitatively or *** feeding and polymeric diets are equally effective at bringing about remission in Crohn's disease(CD).Parenteral feeding is also effective,although none of these methods is as effective as corticosteroid ***,enteral feeding is preferred in the pediatric population because linear growth is more adequately maintained via this *** diets in patients brought into remission using an elemental diet have been shown to maintain remission for longer *** that aim to isolate culpable food groups have shown that individuals react differently on exposure to or exclusion of various *** commonly identifi ed food sensitivities are cereals,milk,eggs,vegetables and citrus *** that have looked at gut mucosal antigen behavior have shown higher rectal blood flow,in response to specifi c food antigens,in those with CD over healthy *** of sugar shows little evidence of amelioration in *** 3 fatty acids show promise in the treatment of IBD but await larger randomized controlled *** frequently notice that specifi c foods cause aggravation of their *** it has been diffi cult to pinpoint specifi c foods,with advances in the laboratory tests and food supplements available,the aim is to prolong remission in these patients using dietary measures,and reduce the need for pharmacotherapy and surgical intervention.

关键词： Crohn’s disease Ulcerative colitis Exclusion diet Elimination diet

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Selenium as a chemopreventive agent in experimentally induced colon carcinogenesis

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World Journal of Gastrointestinal Oncology 2009年第1期1卷 74-81页

作者： Fereshteh Ezzati Ghadi Abdollah Ramzani Ghara Shalmoli Bhattacharyya devinder kumar Dhawan Department of Biophysics Basic Medical Sciences BlockPanjab University Department of Biophysics Post graduate Institute of Medical Education and Research

AIM:To elucidate the chemopreventive efficacy of selenium during experimentally induced colon ***:Thirty-two male wistar rats were divided into four groups:group □(normal control);group □[1,2-dimethylhydrazine(DMH) treated];group □ (selenium treated);and group □ (DMH + selenium treated).Groups □ and □ were given subcutaneous injections of DMH(30 mg/kg body weight) every week for 20 ***,in the form of sodium selenite,was given to groups □ and at 1 ppm in drinking water ad libitum for 20 *** the end of the study,rats were sacrificed and their colons were analyzed for the development of tumors,antioxidant enzyme levels and histological ***:100 of the DMH treated rats developed tumors,which was reduced to 60 upon simultaneous selenium ***,tumor multiplicity decreased to 1.1 following selenium supplementation to DMH treated *** of lipid peroxidation,glutathione-S-transferase,superoxide dismutase(SOD),catalase,and glutathione peroxidase(GPx) decreased following DMH treatment,whereas levels of glutathione(GSH) and glutathione reductase(GR) significantly increased in DMH treated *** administration to DMH treated rats led to an increase in the levels of lipid peroxidation,SOD,catalase,glutathione-S-transferase and GPx,but decreased the levels of GSH and *** studies on DMH treated rats revealed dysplasia of the colonic histoarchitecture,which showed signs of improvement following selenium ***:The study suggests the antioxidative potential of selenium is a major factor in providing protection from development of experimentally induced colon carcinogenesis.

关键词： Colon cancer Selenium Antioxidant enzyme Histopathology Dimethylhydrazine

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True Cultural Ambassadors

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中印对话（英文版） 2023年第3期 60-61页

作者： staff reporter devinder kumar 不详

Jackie Chan and Bruce Lee's popularity have transcended age,gender,and geographic boundaries to culturally connect China and *** Bruce Leeare world-famous and especially popularin *** movies have been dubbed in Hindia... 详细信息

关键词： Bruce True popularity

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An OMR Based Automatic Music Player

An OMR Based Automatic Music Player

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2011 3rd International Conference on Computer Research and Development(ICCRD 2011)

作者： Amarjot Singh Ketan Bacchuwar Akash Choubey Srikrishna Karanam devinder kumar Dept.of Electrical Engineering NIT Warangal Warangal India Dept.of ECE NIT Warangal Warangal India.

Automated learning systems used to extract useful information from musical scripts, play a major role in optical music recognition. Optical music recognition or OMR has been widely used to extract the musical notations and knowledge from old scripts and thus enclose lot of importance in retrieving historical data. The field of pattern recognition and knowledge representation has to be symmetrically used for music notation recognition making it a challenging problem. Most of the methods used for OMR recognition and extraction like HMM’s, Neural etc mentioned in literature have errors which require human operators to be rectified. The paper proposes a novel automatic music recognition system which can be effectively used to recognize sheet or printed scores into a playable platform under the different conditions of blur, illumination variations, noise etc. The paper uses an enhancement supported threshold GA based pre-processing methodology for bimodal images further compares with the Sobel filtered and standard GA outputs for the same. The methodology makes use of an enhanced image obtained by histogram equalization followed by image segmentation using a specific threshold. The threshold can be obtained using genetic algorithms. GA based segmentation technique is codified as an optimization problem used efficiently to search maxima and minima from the histogram of the image to obtain the threshold for segmentation. The system described is capable of extracting normal images as well as images with noise, images from old scripts.

关键词： Genetic Algorithm Optical Character Recogntion Histogram Sobel Filter

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