Objective:Transurethral resection of bladder tumor is one of the most common everyday urological procedures.This kind of surgery demands a set of skills that need training and experience.In this review,we aimed to inv...Objective:Transurethral resection of bladder tumor is one of the most common everyday urological procedures.This kind of surgery demands a set of skills that need training and experience.In this review,we aimed to investigate the current literature to find out if simulators,phantoms,and other training models could be used as a tool for teaching urologists.Methods:A systematic review was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses statement and the recommendations of the European Association of Urology guidelines for conducting systematic reviews.Fifteen out of 932 studies met our inclusion criteria and are presented in the current review.Results:The UroTrainer(Karl Storz GmbH,Tuttlingen,Germany),a virtual reality training simulator,achieved positive feedback and an excellent face and construct validity by the participants.The inspection of bladder mucosa,blood loss,tumor resection,and procedural time was improved after the training,especially for inexperienced urologists and medical students.The construct validity of UroSim®(VirtaMed,Zurich,Switzerland)was established.SIMBLA simulator(Samed GmbH,Dresden,Germany)was found to be a realistic and useful tool by experts and urologists with intermediate experience.The test objective competency model based on SIMBLA simulator could be used for evaluating urologists.The porcine model of the Asian Urological Surgery Training and Education Group also received positive feedback by the participants that tried it.The Simulation and Technology Enhanced Learning Initiative Project had an extraordinary face and content validity,and 60%of participants would like to use the simulators in the future.The 5-day multimodal training curriculum“Boot Camp”in the United Kingdom achieved an increase of the level of confidence of the participants that lasted months after the project.Conclusion:Simulators and courses or curricula based on a simulator training could be a valuable learning tool for any surgeon,and there is no doubt that they should be a part of every urologist's technical education.展开更多
本文是《时尚学:时尚研究概述》(Fashion-ology:An Introduction to Fashion Studies)一书的前言部分,概括了书中的一些主要观点。作者认为应该将对时尚的研究与对衣着的研究区分开来。时尚无关服饰,它只是一种信仰。她主张应该把时尚...本文是《时尚学:时尚研究概述》(Fashion-ology:An Introduction to Fashion Studies)一书的前言部分,概括了书中的一些主要观点。作者认为应该将对时尚的研究与对衣着的研究区分开来。时尚无关服饰,它只是一种信仰。她主张应该把时尚研究列入社会科学、人文科学的研究范围内,并介绍了人们在心理学、社会心理学、历史学、艺术史、文化人类学和经济学等领域对时尚的研究。她所提倡的时尚理论认为,对时尚的研究应该从时尚系统入手,研究它整个运作过程中的社会属性。展开更多
High strength aluminium alloy AA7075(Al-Zn-Mg-Cu) is a precipitate hardenable alloy widely used in the aerospace,defense,marine and automobile industries.Use of the heat treatable aluminium alloys in all these sectors...High strength aluminium alloy AA7075(Al-Zn-Mg-Cu) is a precipitate hardenable alloy widely used in the aerospace,defense,marine and automobile industries.Use of the heat treatable aluminium alloys in all these sectors is ever-increasing owing to their excellent strength-toweight ratio and reasonably good corrosion resistance.The shortage in corrosion resistance,however,usually poses negative concern about their reliability and lifetime when they service in the variable marine environments.These alloys also exhibit low weldability due to poor solidification microstructure,porosity in fusion zone and lose their mechanical properties when they are welded by fusion welding techniques.Friction stir welding(FSW) is a reliable technique to retain the properties of the alloy as the joining takes place in the solid state.The welds are susceptible to corrosion due to the microstructural changes in the weld nugget during FSW.In this work,the effect of post weld treatments,viz.,peak aging(T6) and retrogression & reaging(RRA),on the microstructure,mechanical properties and pitting corrosion has been studied.Friction stir welding of 8 mm-thick AA7075 alloy was carried out.The microstructural changes of base metal and nugget zone of friction stir welds were studied using optical microscopy,scanning electron microscopy and transmission electron microscopy.Tensile and hardness test of base metal and welds has been carried out.Pitting corrosion resistance was determined through dynamic polarization test.It was observed that the hardness and strength of weld were observed to be comparatively high in peak aged(T6) condition but the welds showed poor corrosion resistance.The resistance to pitting corrosion was improved and the mechanical properties were maintained by RRA treatment.The resistance to pitting corrosion was improved in RRA condition with the minimum loss of weld strength.展开更多
This article introduces a singleton type-1 fuzzy logic system(T1-SFLS) controller and Fuzzy-WDO hybrid for the autonomous mobile robot navigation and collision avoidance in an unknown static and dynamic environment. T...This article introduces a singleton type-1 fuzzy logic system(T1-SFLS) controller and Fuzzy-WDO hybrid for the autonomous mobile robot navigation and collision avoidance in an unknown static and dynamic environment. The WDO(Wind Driven Optimization) algorithm is used to optimize and tune the input/output membership function parameters of the fuzzy controller. The WDO algorithm is working based on the atmospheric motion of infinitesimal small air parcels navigates over an N-dimensional search domain. The performance of this proposed technique has compared through many computer simulations and real-time experiments by using Khepera-Ⅲ mobile robot. As compared to the T1-SFLS controller the Fuzzy-WDO algorithm is found good agreement for mobile robot navigation.展开更多
Friction stir welding(FSW) of high strength aluminum alloys has been emerged as an alternative joining technique to avoid the problems during fusion welding.In recent times FSW is being used for armor grade AA7075 alu...Friction stir welding(FSW) of high strength aluminum alloys has been emerged as an alternative joining technique to avoid the problems during fusion welding.In recent times FSW is being used for armor grade AA7075 aluminum alloy in defense,aerospace and marine applications where it has to serve in non uniform loading and corrosive environments.Even though friction stir welds of AA7075 alloy possess better mechanical properties but suffer from poor corrosion resistance.The present work involves use of retrogression and reaging(RRA) post weld heat treatment to improve the corrosion resistance of welded joints of aluminum alloys.An attempt also has been made to change the chemical composition of the weld nugget by adding B4C nano particles with the aid of the FSW on a specially prepared base metal plate in butt position.The effects of peak aged condition(T6),RRA and addition of B4C nano particles on microstructure,hardness and pitting corrosion of nugget zone of the friction stir welds of AA7075 alloy have been studied.Even though RRA improved the pitting corrosion resistance,its hardness was slightly lost.Significant improvement in pitting corrosion resistance was achieved with addition of boron carbide powder and post weld heat treatment of RRA.展开更多
The influence of different welding speeds and rotary speeds on the formation and mechanical properties of friction stirweld joints of armor grade aluminum alloy was presented.The developed weld joints were characteriz...The influence of different welding speeds and rotary speeds on the formation and mechanical properties of friction stirweld joints of armor grade aluminum alloy was presented.The developed weld joints were characterized by bend tests,micro-hardness tests,tensile tests,optical and scanning electron microscopies.Mechanical properties(i.e.,micro-hardness,ultimatetensile strength and elongation to fracture)increased with the increase in rotary speed or decrease in welding speed.The effect ofwelding speed on micro-hardness of heat affected zones was more profound than the rotary speeds.The welding speeds and rotaryspeeds influenced the mechanical properties and their effects on various mechanical properties of the friction stir welded joints canbe predicted with the help of regression models.展开更多
Blast pressure measurements of a controlled underwater explosion in the sea were carried out.An explosive of 25-kg trinitro-toluene(TNT)equivalent was detonated,and the blast pressures were recorded by eight diferent ...Blast pressure measurements of a controlled underwater explosion in the sea were carried out.An explosive of 25-kg trinitro-toluene(TNT)equivalent was detonated,and the blast pressures were recorded by eight diferent high-performance pressure sensors that work at the nonresonant high-voltage output in adverse underwater conditions.Recorded peak pressure values are used to establish a relationship in the well-known form of empirical underwater explosion(UNDEX)loading formula.Constants of the formula are redetermined by employing the least-squares method in two diferent forms for best ftting to the measured data.The newly determined constants are found to be only slightly diferent from the generally accepted ones.展开更多
CBM has been recognized as a significant natural gas resource for a long time. Recently, CO_2 sequestration in coalbeds for ECBM has been attracting growing attention because of greater concerns about the effects of g...CBM has been recognized as a significant natural gas resource for a long time. Recently, CO_2 sequestration in coalbeds for ECBM has been attracting growing attention because of greater concerns about the effects of greenhouse gases and the emerging commercial significance of CBM. Reservoir-simulation technology,as a useful tool of reservoir development, has the capability to provide us with an economic means to solve complex reservoir-engineering problems with efficiency. The pore structure of coal is highly heterogeneous, and the heterogeneity of the pores depends on the coal type and rank.展开更多
Ti6Al4V powders with three different particle size distributions(0–20, 20–45, and 45–75 μm) were used to evaluate the effect of the particle size distribution on the solid-state sintering and their mechanical prop...Ti6Al4V powders with three different particle size distributions(0–20, 20–45, and 45–75 μm) were used to evaluate the effect of the particle size distribution on the solid-state sintering and their mechanical properties. The sintering kinetics was determined by dilatometry at temperatures from 900 to 1260°C. The mechanical properties of the sintered samples were evaluated by microhardness and compression tests. The sintering kinetics indicated that the predominant mechanism depends on the relative density irrespective of the particle size used. The mechanical properties of the sintered samples are adversely affected by increasing pore volume fraction. The elastic Young's modulus and yield stress follow a power law function of the relative density. The fracture behavior after compression is linked to the neck size developed during sintering, exhibiting two different mechanisms of failure: interparticle neck breaking and intergranular cracking in samples with relative densities below and above of 90%, respectively. The main conclusion is that relative density is responsible for the kinetics, mechanical properties, and failure behavior of Ti6 Al4 V powders.展开更多
The cerium (Ce3+) doped yttrium aluminium borate (YAB) phosphor was synthesized by modified solid state reaction. The phosphor's phase purity and its emission properties were studied using powder X-ray diffracti...The cerium (Ce3+) doped yttrium aluminium borate (YAB) phosphor was synthesized by modified solid state reaction. The phosphor's phase purity and its emission properties were studied using powder X-ray diffraction pattern and photoluminescence spectroscopy. The synthesized YAB had rhomobohedral crystal structure. The phosphor had two different excitation and emission spectra. By 325 nm excitation, the phosphor had emission at 373 nm and with 363 nm excitation; the phosphor gave violet-blue emission at 418 nm. The UV emission of the phosphor originated due to Ce3+ ions at the yttrium site and violet-blue emission owing to Ce3+ ions at non-regular sites viz., A13+ and interstitial sites. The emission intensity of the phosphor was enhanced when monovalent ions (K+, Na+, and F) were added as co-dopants. The crucial role of ionic radii of monovalent co-dopants on the emission enhancement of the YAB:Ce3+ phosphor was reported. Thermogravimetric study showed that the YAB possessed high thermal stability at up to 900 ℃.展开更多
Our main objective is to study properties of a fuzzy ideals(fuzzy dual ideals).A study of special types of fuzzy ideals(fuzzy dual ideals) is also furnished.Some properties of a fuzzy ideals(fuzzy dual ideals) are fur...Our main objective is to study properties of a fuzzy ideals(fuzzy dual ideals).A study of special types of fuzzy ideals(fuzzy dual ideals) is also furnished.Some properties of a fuzzy ideals(fuzzy dual ideals) are furnished.Properties of a fuzzy lattice homomorphism are discussed.Fuzzy ideal lattice of a fuzzy lattice is defined and discussed.Some results in fuzzy distributive lattice are proved.展开更多
p-cycle is one of the most promising technique of span protection in optical transport networks with mesh-like efficiency and ring-like speed.Longer p-cycle provides better efficiency in term of spare capacity,but lon...p-cycle is one of the most promising technique of span protection in optical transport networks with mesh-like efficiency and ring-like speed.Longer p-cycle provides better efficiency in term of spare capacity,but longer restored path increases end-to-end propagation delay,which reduces the reliability of the restored network.Hence,minimization of restoration path is a critical issue in p-cycle based protection network.In this paper,two new dynamic reconfiguration approaches namely inter-cycles switching(ICS) and local restoration paths(LRP) are discussed to reduce the length of restored paths in existing optimal spare capacity design of p-cycle.Both proposed approaches are meant to utilize the idle p-cycles thus significantly reducing the path length.This reduction in restored path length also releases the redundant spare capacity.展开更多
Objective:To investigate the outbreak of unknown fever at Siliguri town,Darjeeling District on request from the State Health Department,Government of West Bengal.Methods: Investigations were made to the affected wards...Objective:To investigate the outbreak of unknown fever at Siliguri town,Darjeeling District on request from the State Health Department,Government of West Bengal.Methods: Investigations were made to the affected wards,Sub Divisional Hospital and the nursing homes of Siliguri Town.Duration of illness was 3-5 days.Interesting observations were made in some cases which had gastrointestinal disorders with high serum glutamate pyruvate transaminase(SGPT) and serum glutamic oxaloacetic transaminase(SCOT) levels.A total of 69 blood samples and 7 throat swabs(in Minimum Essential Media) were collected and brought to the ICMR Virus Unit, Kolkata for analysis.Mosquitoes from different affected areas were collected for the identification of the definite vector.Results:Amongst the 69 blood samples,42(60.86%) were positive to IgM antibody against dengue virus by Mac enzyme-linked immunosorbent assay(ELISA) test.No IgM antibody to Japanese encephalitis virus was detected among the collected blood samples.Based on the clinical symptoms,presence of IgM antibody to dengue virus and identification of Aedes mosquito,it amply proves that,the illness of those cases were due to dengue virus infection. Conclusions:Based on clinical-epidemiological observations of the investigations the possibility of a communicable disease of viral origin,the detection of IgM antibody and the identification of Aedes egypti,and the potential circulation of denge virus in Siliguri town for the first time were all suggested.展开更多
AIM To characterize the role of apolipoprotein B100(apoB 100) in hepatitis C viral(HCV) infection. METHODS In this study, we utilize a gene editing tool, transcription activator-like effector nucleases(TALENs), to gen...AIM To characterize the role of apolipoprotein B100(apoB 100) in hepatitis C viral(HCV) infection. METHODS In this study, we utilize a gene editing tool, transcription activator-like effector nucleases(TALENs), to generate human hepatoma cells with a stable genetic deletion of APOB to assess of apoB in HCV. Using infectious cell culture-competent HCV, viral pseudoparticles, replicon models, and lipidomic analysis we determined the contribution of apoB to each step of the viral lifecycle. We further studied the effect of mipomersen, an FDAapproved antisense inhibitor of apoB 100, on HCV using in vitro cell-culture competent HCV and determined itsimpact on viral infectivity with the TCID50 method. RESULTS We found that apo B100 is indispensable for HCV infection. Using the JFH-1 fully infectious cell-culture competent virus in Huh 7 hepatoma cells with TALENmediated gene deletion of apoB(APOB KO), we found a significant reduction in HCV RNA and protein levels following infection. Pseudoparticle and replicon models demonstrated that apo B did not play a role in HCV entry or replication. However, the virus produced by APOB KO cells had significantly diminished infectivity as measured by the TCID-50 method compared to wildtype virus. Lipidomic analysis demonstrated that these virions have a fundamentally altered lipidome, with complete depletion of cholesterol esters. We further demonstrate that inhibition of apoB using mipomersen, an FDA-approved anti-sense oligonucleotide, results in a potent anti-HCV effect and significantly reduces the infectivity of the virus. CONCLUSION Apo B is required for the generation of fully infectious HCV virions, and inhibition of apo B with mipomersen blocks HCV. Targeting lipid metabolic pathways to impair viral infectivity represents a novel host targeted strategy to inhibit HCV.展开更多
The public is increasingly using social media platforms such as Twitter and Facebook to express their views on a variety of topics.As a result,social media has emerged as the most effective and largest open source for...The public is increasingly using social media platforms such as Twitter and Facebook to express their views on a variety of topics.As a result,social media has emerged as the most effective and largest open source for obtaining public opinion.Single node computational methods are inefficient for sentiment analysis on such large datasets.Supercomputers or parallel or distributed proces-sing are two options for dealing with such large amounts of data.Most parallel programming frameworks,such as MPI(Message Processing Interface),are dif-ficult to use and scale in environments where supercomputers are expensive.Using the Apache Spark Parallel Model,this proposed work presents a scalable system for sentiment analysis on Twitter.A Spark-based Naive Bayes training technique is suggested for this purpose;unlike prior research,this algorithm does not need any disk access.Millions of tweets have been classified using the trained model.Experiments with various-sized clusters reveal that the suggested strategy is extremely scalable and cost-effective for larger data sets.It is nearly 12 times quicker than the Map Reduce-based model and nearly 21 times faster than the Naive Bayes Classifier in Apache Mahout.To evaluate the framework’s scalabil-ity,we gathered a large training corpus from Twitter.The accuracy of the classi-fier trained with this new dataset was more than 80%.展开更多
Twitter is a radiant platform with a quick and effective technique to analyze users’perceptions of activities on social media.Many researchers and industry experts show their attention to Twitter sentiment analysis t...Twitter is a radiant platform with a quick and effective technique to analyze users’perceptions of activities on social media.Many researchers and industry experts show their attention to Twitter sentiment analysis to recognize the stakeholder group.The sentiment analysis needs an advanced level of approaches including adoption to encompass data sentiment analysis and various machine learning tools.An assessment of sentiment analysis in multiple fields that affect their elevations among the people in real-time by using Naive Bayes and Support Vector Machine(SVM).This paper focused on analysing the distinguished sentiment techniques in tweets behaviour datasets for various spheres such as healthcare,behaviour estimation,etc.In addition,the results in this work explore and validate the statistical machine learning classifiers that provide the accuracy percentages attained in terms of positive,negative and neutral tweets.In this work,we obligated Twitter Application Programming Interface(API)account and programmed in python for sentiment analysis approach for the computational measure of user’s perceptions that extract a massive number of tweets and provide market value to the Twitter account proprietor.To distinguish the results in terms of the performance evaluation,an error analysis investigates the features of various stakeholders comprising social media analytics researchers,Natural Language Processing(NLP)developers,engineering managers and experts involved to have a decision-making approach.展开更多
Missing, swapping, false insurance claims and reallocation of pet animals (dog) are global problems throughout the world and research done to solve this problem is minimal. Traditional biometrics and non-biometrics me...Missing, swapping, false insurance claims and reallocation of pet animals (dog) are global problems throughout the world and research done to solve this problem is minimal. Traditional biometrics and non-biometrics methods have their own boundaries and they fail to provide competent level of security to pet animal (dog). The work on animal identification based on their phenotype appearance (coat patterns) has been an active research area in recent years and automatic face recognition for dog is not reported in the literature. Dog identification needs innovative research to protect the pet animal. Therefore it is imperative to initiate research, so that future face recognition algorithm will be able to solve this important problem for identification of pet animal (like dog, cat). In this paper an attempt has been made to minimize the above mentioned problems by biometrics face recognition of dog. The contributions of this research are: 1) implementation of an existing biometrics algorithm which mitigates the effects of covariates for dogs;2) proposed fusion based method for recognition of pet animal with 94.86% accuracy. Thus in this paper, we have tried to demonstrate that face recognition of dog can be used to recognize the dog efficiently.展开更多
文摘Objective:Transurethral resection of bladder tumor is one of the most common everyday urological procedures.This kind of surgery demands a set of skills that need training and experience.In this review,we aimed to investigate the current literature to find out if simulators,phantoms,and other training models could be used as a tool for teaching urologists.Methods:A systematic review was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses statement and the recommendations of the European Association of Urology guidelines for conducting systematic reviews.Fifteen out of 932 studies met our inclusion criteria and are presented in the current review.Results:The UroTrainer(Karl Storz GmbH,Tuttlingen,Germany),a virtual reality training simulator,achieved positive feedback and an excellent face and construct validity by the participants.The inspection of bladder mucosa,blood loss,tumor resection,and procedural time was improved after the training,especially for inexperienced urologists and medical students.The construct validity of UroSim®(VirtaMed,Zurich,Switzerland)was established.SIMBLA simulator(Samed GmbH,Dresden,Germany)was found to be a realistic and useful tool by experts and urologists with intermediate experience.The test objective competency model based on SIMBLA simulator could be used for evaluating urologists.The porcine model of the Asian Urological Surgery Training and Education Group also received positive feedback by the participants that tried it.The Simulation and Technology Enhanced Learning Initiative Project had an extraordinary face and content validity,and 60%of participants would like to use the simulators in the future.The 5-day multimodal training curriculum“Boot Camp”in the United Kingdom achieved an increase of the level of confidence of the participants that lasted months after the project.Conclusion:Simulators and courses or curricula based on a simulator training could be a valuable learning tool for any surgeon,and there is no doubt that they should be a part of every urologist's technical education.
文摘本文是《时尚学:时尚研究概述》(Fashion-ology:An Introduction to Fashion Studies)一书的前言部分,概括了书中的一些主要观点。作者认为应该将对时尚的研究与对衣着的研究区分开来。时尚无关服饰,它只是一种信仰。她主张应该把时尚研究列入社会科学、人文科学的研究范围内,并介绍了人们在心理学、社会心理学、历史学、艺术史、文化人类学和经济学等领域对时尚的研究。她所提倡的时尚理论认为,对时尚的研究应该从时尚系统入手,研究它整个运作过程中的社会属性。
文摘High strength aluminium alloy AA7075(Al-Zn-Mg-Cu) is a precipitate hardenable alloy widely used in the aerospace,defense,marine and automobile industries.Use of the heat treatable aluminium alloys in all these sectors is ever-increasing owing to their excellent strength-toweight ratio and reasonably good corrosion resistance.The shortage in corrosion resistance,however,usually poses negative concern about their reliability and lifetime when they service in the variable marine environments.These alloys also exhibit low weldability due to poor solidification microstructure,porosity in fusion zone and lose their mechanical properties when they are welded by fusion welding techniques.Friction stir welding(FSW) is a reliable technique to retain the properties of the alloy as the joining takes place in the solid state.The welds are susceptible to corrosion due to the microstructural changes in the weld nugget during FSW.In this work,the effect of post weld treatments,viz.,peak aging(T6) and retrogression & reaging(RRA),on the microstructure,mechanical properties and pitting corrosion has been studied.Friction stir welding of 8 mm-thick AA7075 alloy was carried out.The microstructural changes of base metal and nugget zone of friction stir welds were studied using optical microscopy,scanning electron microscopy and transmission electron microscopy.Tensile and hardness test of base metal and welds has been carried out.Pitting corrosion resistance was determined through dynamic polarization test.It was observed that the hardness and strength of weld were observed to be comparatively high in peak aged(T6) condition but the welds showed poor corrosion resistance.The resistance to pitting corrosion was improved and the mechanical properties were maintained by RRA treatment.The resistance to pitting corrosion was improved in RRA condition with the minimum loss of weld strength.
文摘This article introduces a singleton type-1 fuzzy logic system(T1-SFLS) controller and Fuzzy-WDO hybrid for the autonomous mobile robot navigation and collision avoidance in an unknown static and dynamic environment. The WDO(Wind Driven Optimization) algorithm is used to optimize and tune the input/output membership function parameters of the fuzzy controller. The WDO algorithm is working based on the atmospheric motion of infinitesimal small air parcels navigates over an N-dimensional search domain. The performance of this proposed technique has compared through many computer simulations and real-time experiments by using Khepera-Ⅲ mobile robot. As compared to the T1-SFLS controller the Fuzzy-WDO algorithm is found good agreement for mobile robot navigation.
文摘Friction stir welding(FSW) of high strength aluminum alloys has been emerged as an alternative joining technique to avoid the problems during fusion welding.In recent times FSW is being used for armor grade AA7075 aluminum alloy in defense,aerospace and marine applications where it has to serve in non uniform loading and corrosive environments.Even though friction stir welds of AA7075 alloy possess better mechanical properties but suffer from poor corrosion resistance.The present work involves use of retrogression and reaging(RRA) post weld heat treatment to improve the corrosion resistance of welded joints of aluminum alloys.An attempt also has been made to change the chemical composition of the weld nugget by adding B4C nano particles with the aid of the FSW on a specially prepared base metal plate in butt position.The effects of peak aged condition(T6),RRA and addition of B4C nano particles on microstructure,hardness and pitting corrosion of nugget zone of the friction stir welds of AA7075 alloy have been studied.Even though RRA improved the pitting corrosion resistance,its hardness was slightly lost.Significant improvement in pitting corrosion resistance was achieved with addition of boron carbide powder and post weld heat treatment of RRA.
基金DST Govt.of India for providing financial support through grant No.SR3/S3/MERC/005/2009 to carry out this work
文摘The influence of different welding speeds and rotary speeds on the formation and mechanical properties of friction stirweld joints of armor grade aluminum alloy was presented.The developed weld joints were characterized by bend tests,micro-hardness tests,tensile tests,optical and scanning electron microscopies.Mechanical properties(i.e.,micro-hardness,ultimatetensile strength and elongation to fracture)increased with the increase in rotary speed or decrease in welding speed.The effect ofwelding speed on micro-hardness of heat affected zones was more profound than the rotary speeds.The welding speeds and rotaryspeeds influenced the mechanical properties and their effects on various mechanical properties of the friction stir welded joints canbe predicted with the help of regression models.
文摘Blast pressure measurements of a controlled underwater explosion in the sea were carried out.An explosive of 25-kg trinitro-toluene(TNT)equivalent was detonated,and the blast pressures were recorded by eight diferent high-performance pressure sensors that work at the nonresonant high-voltage output in adverse underwater conditions.Recorded peak pressure values are used to establish a relationship in the well-known form of empirical underwater explosion(UNDEX)loading formula.Constants of the formula are redetermined by employing the least-squares method in two diferent forms for best ftting to the measured data.The newly determined constants are found to be only slightly diferent from the generally accepted ones.
文摘CBM has been recognized as a significant natural gas resource for a long time. Recently, CO_2 sequestration in coalbeds for ECBM has been attracting growing attention because of greater concerns about the effects of greenhouse gases and the emerging commercial significance of CBM. Reservoir-simulation technology,as a useful tool of reservoir development, has the capability to provide us with an economic means to solve complex reservoir-engineering problems with efficiency. The pore structure of coal is highly heterogeneous, and the heterogeneity of the pores depends on the coal type and rank.
基金the National Laboratory SEDEAM-National Council for Science and Technology (CONACYT)ECOS M15P01 for the financial support and the facilities to develop this study
文摘Ti6Al4V powders with three different particle size distributions(0–20, 20–45, and 45–75 μm) were used to evaluate the effect of the particle size distribution on the solid-state sintering and their mechanical properties. The sintering kinetics was determined by dilatometry at temperatures from 900 to 1260°C. The mechanical properties of the sintered samples were evaluated by microhardness and compression tests. The sintering kinetics indicated that the predominant mechanism depends on the relative density irrespective of the particle size used. The mechanical properties of the sintered samples are adversely affected by increasing pore volume fraction. The elastic Young's modulus and yield stress follow a power law function of the relative density. The fracture behavior after compression is linked to the neck size developed during sintering, exhibiting two different mechanisms of failure: interparticle neck breaking and intergranular cracking in samples with relative densities below and above of 90%, respectively. The main conclusion is that relative density is responsible for the kinetics, mechanical properties, and failure behavior of Ti6 Al4 V powders.
文摘The cerium (Ce3+) doped yttrium aluminium borate (YAB) phosphor was synthesized by modified solid state reaction. The phosphor's phase purity and its emission properties were studied using powder X-ray diffraction pattern and photoluminescence spectroscopy. The synthesized YAB had rhomobohedral crystal structure. The phosphor had two different excitation and emission spectra. By 325 nm excitation, the phosphor had emission at 373 nm and with 363 nm excitation; the phosphor gave violet-blue emission at 418 nm. The UV emission of the phosphor originated due to Ce3+ ions at the yttrium site and violet-blue emission owing to Ce3+ ions at non-regular sites viz., A13+ and interstitial sites. The emission intensity of the phosphor was enhanced when monovalent ions (K+, Na+, and F) were added as co-dopants. The crucial role of ionic radii of monovalent co-dopants on the emission enhancement of the YAB:Ce3+ phosphor was reported. Thermogravimetric study showed that the YAB possessed high thermal stability at up to 900 ℃.
基金UGC,New Delhi for financial support through scheme F.No 33-109/2007(SR)
文摘Our main objective is to study properties of a fuzzy ideals(fuzzy dual ideals).A study of special types of fuzzy ideals(fuzzy dual ideals) is also furnished.Some properties of a fuzzy ideals(fuzzy dual ideals) are furnished.Properties of a fuzzy lattice homomorphism are discussed.Fuzzy ideal lattice of a fuzzy lattice is defined and discussed.Some results in fuzzy distributive lattice are proved.
文摘p-cycle is one of the most promising technique of span protection in optical transport networks with mesh-like efficiency and ring-like speed.Longer p-cycle provides better efficiency in term of spare capacity,but longer restored path increases end-to-end propagation delay,which reduces the reliability of the restored network.Hence,minimization of restoration path is a critical issue in p-cycle based protection network.In this paper,two new dynamic reconfiguration approaches namely inter-cycles switching(ICS) and local restoration paths(LRP) are discussed to reduce the length of restored paths in existing optimal spare capacity design of p-cycle.Both proposed approaches are meant to utilize the idle p-cycles thus significantly reducing the path length.This reduction in restored path length also releases the redundant spare capacity.
文摘Objective:To investigate the outbreak of unknown fever at Siliguri town,Darjeeling District on request from the State Health Department,Government of West Bengal.Methods: Investigations were made to the affected wards,Sub Divisional Hospital and the nursing homes of Siliguri Town.Duration of illness was 3-5 days.Interesting observations were made in some cases which had gastrointestinal disorders with high serum glutamate pyruvate transaminase(SGPT) and serum glutamic oxaloacetic transaminase(SCOT) levels.A total of 69 blood samples and 7 throat swabs(in Minimum Essential Media) were collected and brought to the ICMR Virus Unit, Kolkata for analysis.Mosquitoes from different affected areas were collected for the identification of the definite vector.Results:Amongst the 69 blood samples,42(60.86%) were positive to IgM antibody against dengue virus by Mac enzyme-linked immunosorbent assay(ELISA) test.No IgM antibody to Japanese encephalitis virus was detected among the collected blood samples.Based on the clinical symptoms,presence of IgM antibody to dengue virus and identification of Aedes mosquito,it amply proves that,the illness of those cases were due to dengue virus infection. Conclusions:Based on clinical-epidemiological observations of the investigations the possibility of a communicable disease of viral origin,the detection of IgM antibody and the identification of Aedes egypti,and the potential circulation of denge virus in Siliguri town for the first time were all suggested.
基金Supported by the United States National Institutes of Health(NIH),No.F32-DK097855(to Schaefer EAK),No.T32-DK008191(to Motola DL),No.K08-DK088951(to Peng LF),and No.K24-DK078772(to Chung RT)
文摘AIM To characterize the role of apolipoprotein B100(apoB 100) in hepatitis C viral(HCV) infection. METHODS In this study, we utilize a gene editing tool, transcription activator-like effector nucleases(TALENs), to generate human hepatoma cells with a stable genetic deletion of APOB to assess of apoB in HCV. Using infectious cell culture-competent HCV, viral pseudoparticles, replicon models, and lipidomic analysis we determined the contribution of apoB to each step of the viral lifecycle. We further studied the effect of mipomersen, an FDAapproved antisense inhibitor of apoB 100, on HCV using in vitro cell-culture competent HCV and determined itsimpact on viral infectivity with the TCID50 method. RESULTS We found that apo B100 is indispensable for HCV infection. Using the JFH-1 fully infectious cell-culture competent virus in Huh 7 hepatoma cells with TALENmediated gene deletion of apoB(APOB KO), we found a significant reduction in HCV RNA and protein levels following infection. Pseudoparticle and replicon models demonstrated that apo B did not play a role in HCV entry or replication. However, the virus produced by APOB KO cells had significantly diminished infectivity as measured by the TCID-50 method compared to wildtype virus. Lipidomic analysis demonstrated that these virions have a fundamentally altered lipidome, with complete depletion of cholesterol esters. We further demonstrate that inhibition of apoB using mipomersen, an FDA-approved anti-sense oligonucleotide, results in a potent anti-HCV effect and significantly reduces the infectivity of the virus. CONCLUSION Apo B is required for the generation of fully infectious HCV virions, and inhibition of apo B with mipomersen blocks HCV. Targeting lipid metabolic pathways to impair viral infectivity represents a novel host targeted strategy to inhibit HCV.
文摘The public is increasingly using social media platforms such as Twitter and Facebook to express their views on a variety of topics.As a result,social media has emerged as the most effective and largest open source for obtaining public opinion.Single node computational methods are inefficient for sentiment analysis on such large datasets.Supercomputers or parallel or distributed proces-sing are two options for dealing with such large amounts of data.Most parallel programming frameworks,such as MPI(Message Processing Interface),are dif-ficult to use and scale in environments where supercomputers are expensive.Using the Apache Spark Parallel Model,this proposed work presents a scalable system for sentiment analysis on Twitter.A Spark-based Naive Bayes training technique is suggested for this purpose;unlike prior research,this algorithm does not need any disk access.Millions of tweets have been classified using the trained model.Experiments with various-sized clusters reveal that the suggested strategy is extremely scalable and cost-effective for larger data sets.It is nearly 12 times quicker than the Map Reduce-based model and nearly 21 times faster than the Naive Bayes Classifier in Apache Mahout.To evaluate the framework’s scalabil-ity,we gathered a large training corpus from Twitter.The accuracy of the classi-fier trained with this new dataset was more than 80%.
基金This work was supported by Taif University Researchers Supporting Project(TURSP)under number(TURSP-2020/73),Taif University,Taif,Saudi Arabia.
文摘Twitter is a radiant platform with a quick and effective technique to analyze users’perceptions of activities on social media.Many researchers and industry experts show their attention to Twitter sentiment analysis to recognize the stakeholder group.The sentiment analysis needs an advanced level of approaches including adoption to encompass data sentiment analysis and various machine learning tools.An assessment of sentiment analysis in multiple fields that affect their elevations among the people in real-time by using Naive Bayes and Support Vector Machine(SVM).This paper focused on analysing the distinguished sentiment techniques in tweets behaviour datasets for various spheres such as healthcare,behaviour estimation,etc.In addition,the results in this work explore and validate the statistical machine learning classifiers that provide the accuracy percentages attained in terms of positive,negative and neutral tweets.In this work,we obligated Twitter Application Programming Interface(API)account and programmed in python for sentiment analysis approach for the computational measure of user’s perceptions that extract a massive number of tweets and provide market value to the Twitter account proprietor.To distinguish the results in terms of the performance evaluation,an error analysis investigates the features of various stakeholders comprising social media analytics researchers,Natural Language Processing(NLP)developers,engineering managers and experts involved to have a decision-making approach.
文摘Missing, swapping, false insurance claims and reallocation of pet animals (dog) are global problems throughout the world and research done to solve this problem is minimal. Traditional biometrics and non-biometrics methods have their own boundaries and they fail to provide competent level of security to pet animal (dog). The work on animal identification based on their phenotype appearance (coat patterns) has been an active research area in recent years and automatic face recognition for dog is not reported in the literature. Dog identification needs innovative research to protect the pet animal. Therefore it is imperative to initiate research, so that future face recognition algorithm will be able to solve this important problem for identification of pet animal (like dog, cat). In this paper an attempt has been made to minimize the above mentioned problems by biometrics face recognition of dog. The contributions of this research are: 1) implementation of an existing biometrics algorithm which mitigates the effects of covariates for dogs;2) proposed fusion based method for recognition of pet animal with 94.86% accuracy. Thus in this paper, we have tried to demonstrate that face recognition of dog can be used to recognize the dog efficiently.