In this experimental study,magnesium(AZ91D)based boron carbide(B4C)and graphite(Gr)particle reinforced hybrid composite materials were manufactured by stir casting.The tribological and mechanical properties of these c...In this experimental study,magnesium(AZ91D)based boron carbide(B4C)and graphite(Gr)particle reinforced hybrid composite materials were manufactured by stir casting.The tribological and mechanical properties of these composite materials were investigated.The results of the tests revealed that the graphite reinforced hybrid composites exhibited a lower wear loss compared to the unreinforced AZ91D alloy and AZ91D–B4C composites.It was found that with an increase in the B4C content,the wear resistance increased monotonically with hardness and ultimate tensile strength decreased.This study revealed that the addition of both a hard reinforcement(e.g.,B4C)and soft reinforcement(e.g.,graphite)significantly improves the wear resistance of magnesium composites.These entire results designate that the hybrid magnesium composites can be considered as an excellent material where high strength,ultimate tensile strength and wear-resistant components are of major importance,primarily in the aerospace and automotive engineering sectors.展开更多
Operating System(OS)is a critical piece of software that manages a computer’s hardware and resources,acting as the intermediary between the computer and the user.The existing OS is not designed for Big Data and Cloud...Operating System(OS)is a critical piece of software that manages a computer’s hardware and resources,acting as the intermediary between the computer and the user.The existing OS is not designed for Big Data and Cloud Computing,resulting in data processing and management inefficiency.This paper proposes a simplified and improved kernel on an x86 system designed for Big Data and Cloud Computing purposes.The proposed algorithm utilizes the performance benefits from the improved Input/Output(I/O)performance.The performance engineering runs the data-oriented design on traditional data management to improve data processing speed by reducing memory access overheads in conventional data management.The OS incorporates a data-oriented design to“modernize”various Data Science and management aspects.The resulting OS contains a basic input/output system(BIOS)bootloader that boots into Intel 32-bit protected mode,a text display terminal,4 GB paging memory,4096 heap block size,a Hard Disk Drive(HDD)I/O Advanced Technology Attachment(ATA)driver and more.There are also I/O scheduling algorithm prototypes that demonstrate how a simple Sweeping algorithm is superior to more conventionally known I/O scheduling algorithms.A MapReduce prototype is implemented using Message Passing Interface(MPI)for big data purposes.An attempt was made to optimize binary search using modern performance engineering and data-oriented design.展开更多
Recent rapid advancements in communication technology have brought forth the era of Web 3.0,representing a substantial transformation in the Internet landscape.This shift has led to the emergence of various decentrali...Recent rapid advancements in communication technology have brought forth the era of Web 3.0,representing a substantial transformation in the Internet landscape.This shift has led to the emergence of various decentralized metaverse applications that leverage blockchain as their underlying technology to enable users to exchange value directly from point to point.However,blockchains are blind to the real world,and smart contracts cannot directly access data from the external world.To address this limitation,the technology of oracles has been introduced to provide real-world data for smart contracts and other blockchain applications.In this paper,we focus on mitigating the risks associated with oracles providing corrupt or incorrect data.We propose a novel Web 3.0 architecture for the Metaverse based on the multiidentifier network(MIN),and its decentralized blockchain oracle model called Meta Oracle.The experimental results show that the proposed scheme can achieve minor time investment in return for significantly more reliable data and increased throughput.展开更多
The design of an annular combustion chamber in a gas turbine engine is thebackbone of this paper.It is specifically designed for a low bypass turbofan engine in a jettrainer aircraft.The combustion chamber is position...The design of an annular combustion chamber in a gas turbine engine is thebackbone of this paper.It is specifically designed for a low bypass turbofan engine in a jettrainer aircraft.The combustion chamber is positioned in between the compressor and turbine.lt has to be designed based on the constant pressure,enthalpy addition process.The presentmethodology deals with the computation of the initial design parameters from benchmarking ofreal-time industry standards and arriving at optimized values.It is then studied for feasibilityand finalized.Then the various dimensions of the combustor are calculated based on differentempirical formulas.The air mass flow is then distributed across the zones of the combustor.The cooling requirement is met using the cooling holes.Finally the variations of parameters atdifferent points are calculated.The whole combustion chamber is modeled using Siemens NX8.0,a modeling software and presented.The model is then analyzed using various parametersat various stages and levels to determine the optimized design.The aerodynamic flowcharacteristics is simulated numerically by means of ANSYS 14.5 software suite.The air-fuelmixture,combustion-turbulence,thermal and cooling analysis is carried out.The analysis isperformed at various scenarios and compared.The results are then presented in image outputsand graphs.展开更多
Economic analysis of chronic diseases is required for proper allocation of resources and understanding costeffectiveness studies of new therapies. Studies on health care cost of ulcerative colitis （UC） and Crohn＇s ...Economic analysis of chronic diseases is required for proper allocation of resources and understanding costeffectiveness studies of new therapies. Studies on health care cost of ulcerative colitis （UC） and Crohn＇s disease （CD） are reviewed here. These studies were carried out in various countries with disparate health care systems. In the United States, data were often modeled or retrieved from large insurance schemes. Surgery and in-patient hospitalization accounted for over half the outlay on UC and CD. Fistulous disease in CD and parenteral nutrition were very costly. In Canada, overall charges were lower than in the United States, but there too, surgical costs were relatively high. In European studies, economic data were abstracted directly from patients＇ files. One pan-European study examined the outlay on UC and CD in a community-based prospective inception cohort followed for 10 years. Overall costs in Europe were lower than in the United States. Surgery, hospitalization, year of follow-up, disease phenotype in CD and ASCA-positivity impacted significantly on costs. In all studies, the cost data were right skewed, aminosalicylates were expensive drugs, and biological agents the most expensive; moreover indirect costs were not calculated. Infliximab raised costs considerably in CD, but there were no long-term followup studies, so that the cost-benefit of biological agents remains unknown. In conclusion, costs of managing UC and CD vary by country, surgery, genotype and several other factors. The most important question for further research is whether the biological therapies are cost-effective in the long-term.展开更多
BACKGROUND Appendicitis, the inflammation of the appendix, is the most common abdominal surgical emergency requiring expedient surgical intervention. Extendedspectrum beta-lactamases(ESBLs) are bacterial enzymes that ...BACKGROUND Appendicitis, the inflammation of the appendix, is the most common abdominal surgical emergency requiring expedient surgical intervention. Extendedspectrum beta-lactamases(ESBLs) are bacterial enzymes that catalyse the degradation of the betalactam ring of penicillins and cephalosporins(but without carbapenemase activity), leading to resistance of these bacteria to beta-lactam antibiotics. Recent increases in incidence of ESBL-producing bacteria have caused alarm worldwide. Proportion estimates of ESBLEnterobacteriaceae hover around 46% in China, 42% in East Africa, 12% in Germany, and 8% in the United States.CASE SUMMARY The impact of ESBL-producing bacteria on appendiceal abscesses and consequent pelvic abscesses are yet to be examined in depth. A literature review using the search words "appendiceal abscesses" and "ESBL Escherichia coli(E. coli)" revealed very few cases involving ESBL E. coli in any capacity in the context of appendiceal abscesses. This report describes the clinical aspects of a patient with appendicitis whodeveloped a postoperative pelvic abscess infected with ESBL-producing E. coli. In this report, we discuss the risk factors for contracting ESBL E. coli infection in appendicitis and post-appendectomy pelvis abscesses. We also discuss our management approach for postappendectomy ESBL E. coli pelvic abscesses, including drainage, pathogen identification, and pathogen characterisation. When ESBL E. coli is confirmed, carbapenem antibiotics should be promptly administered, as was done efficaciously with this patient. Our report is the first one in a developed country involving ESBL E. coli related surgical complications in association with a routine laparoscopic appendectomy.CONCLUSION Our report is the first involving ESBL E. coli and appendiceal abscesses, and that too consequent to laparoscopic appendectomy.展开更多
文摘In this experimental study,magnesium(AZ91D)based boron carbide(B4C)and graphite(Gr)particle reinforced hybrid composite materials were manufactured by stir casting.The tribological and mechanical properties of these composite materials were investigated.The results of the tests revealed that the graphite reinforced hybrid composites exhibited a lower wear loss compared to the unreinforced AZ91D alloy and AZ91D–B4C composites.It was found that with an increase in the B4C content,the wear resistance increased monotonically with hardness and ultimate tensile strength decreased.This study revealed that the addition of both a hard reinforcement(e.g.,B4C)and soft reinforcement(e.g.,graphite)significantly improves the wear resistance of magnesium composites.These entire results designate that the hybrid magnesium composites can be considered as an excellent material where high strength,ultimate tensile strength and wear-resistant components are of major importance,primarily in the aerospace and automotive engineering sectors.
文摘Operating System(OS)is a critical piece of software that manages a computer’s hardware and resources,acting as the intermediary between the computer and the user.The existing OS is not designed for Big Data and Cloud Computing,resulting in data processing and management inefficiency.This paper proposes a simplified and improved kernel on an x86 system designed for Big Data and Cloud Computing purposes.The proposed algorithm utilizes the performance benefits from the improved Input/Output(I/O)performance.The performance engineering runs the data-oriented design on traditional data management to improve data processing speed by reducing memory access overheads in conventional data management.The OS incorporates a data-oriented design to“modernize”various Data Science and management aspects.The resulting OS contains a basic input/output system(BIOS)bootloader that boots into Intel 32-bit protected mode,a text display terminal,4 GB paging memory,4096 heap block size,a Hard Disk Drive(HDD)I/O Advanced Technology Attachment(ATA)driver and more.There are also I/O scheduling algorithm prototypes that demonstrate how a simple Sweeping algorithm is superior to more conventionally known I/O scheduling algorithms.A MapReduce prototype is implemented using Message Passing Interface(MPI)for big data purposes.An attempt was made to optimize binary search using modern performance engineering and data-oriented design.
基金supported by Shenzhen Fundamental Research Programs under Grant Nos.JCYJ20220531093206015,GXWD20201231165807007-20200807164903001,JCYJ20210324122013036,and JCYJ20190808155607340Guang Dong Prov.R&D Key Programs under Grant Nos.2019B010137001 and 2018B010124001+4 种基金Basic Research Enhancement Program of China under Grant No.2021-JCJQ-JJ-0483National Keystone R&D Program of China under Grant No.2017YFB0803204Natural Science Foundation of China under Grant No.61671001ZTE Industry-University-Institute Fund Project under Grant No.2019ZTE03-01HuaWei Funding under Grant No.TC20201222002。
文摘Recent rapid advancements in communication technology have brought forth the era of Web 3.0,representing a substantial transformation in the Internet landscape.This shift has led to the emergence of various decentralized metaverse applications that leverage blockchain as their underlying technology to enable users to exchange value directly from point to point.However,blockchains are blind to the real world,and smart contracts cannot directly access data from the external world.To address this limitation,the technology of oracles has been introduced to provide real-world data for smart contracts and other blockchain applications.In this paper,we focus on mitigating the risks associated with oracles providing corrupt or incorrect data.We propose a novel Web 3.0 architecture for the Metaverse based on the multiidentifier network(MIN),and its decentralized blockchain oracle model called Meta Oracle.The experimental results show that the proposed scheme can achieve minor time investment in return for significantly more reliable data and increased throughput.
文摘The design of an annular combustion chamber in a gas turbine engine is thebackbone of this paper.It is specifically designed for a low bypass turbofan engine in a jettrainer aircraft.The combustion chamber is positioned in between the compressor and turbine.lt has to be designed based on the constant pressure,enthalpy addition process.The presentmethodology deals with the computation of the initial design parameters from benchmarking ofreal-time industry standards and arriving at optimized values.It is then studied for feasibilityand finalized.Then the various dimensions of the combustor are calculated based on differentempirical formulas.The air mass flow is then distributed across the zones of the combustor.The cooling requirement is met using the cooling holes.Finally the variations of parameters atdifferent points are calculated.The whole combustion chamber is modeled using Siemens NX8.0,a modeling software and presented.The model is then analyzed using various parametersat various stages and levels to determine the optimized design.The aerodynamic flowcharacteristics is simulated numerically by means of ANSYS 14.5 software suite.The air-fuelmixture,combustion-turbulence,thermal and cooling analysis is carried out.The analysis isperformed at various scenarios and compared.The results are then presented in image outputsand graphs.
文摘Economic analysis of chronic diseases is required for proper allocation of resources and understanding costeffectiveness studies of new therapies. Studies on health care cost of ulcerative colitis （UC） and Crohn＇s disease （CD） are reviewed here. These studies were carried out in various countries with disparate health care systems. In the United States, data were often modeled or retrieved from large insurance schemes. Surgery and in-patient hospitalization accounted for over half the outlay on UC and CD. Fistulous disease in CD and parenteral nutrition were very costly. In Canada, overall charges were lower than in the United States, but there too, surgical costs were relatively high. In European studies, economic data were abstracted directly from patients＇ files. One pan-European study examined the outlay on UC and CD in a community-based prospective inception cohort followed for 10 years. Overall costs in Europe were lower than in the United States. Surgery, hospitalization, year of follow-up, disease phenotype in CD and ASCA-positivity impacted significantly on costs. In all studies, the cost data were right skewed, aminosalicylates were expensive drugs, and biological agents the most expensive; moreover indirect costs were not calculated. Infliximab raised costs considerably in CD, but there were no long-term followup studies, so that the cost-benefit of biological agents remains unknown. In conclusion, costs of managing UC and CD vary by country, surgery, genotype and several other factors. The most important question for further research is whether the biological therapies are cost-effective in the long-term.
文摘BACKGROUND Appendicitis, the inflammation of the appendix, is the most common abdominal surgical emergency requiring expedient surgical intervention. Extendedspectrum beta-lactamases(ESBLs) are bacterial enzymes that catalyse the degradation of the betalactam ring of penicillins and cephalosporins(but without carbapenemase activity), leading to resistance of these bacteria to beta-lactam antibiotics. Recent increases in incidence of ESBL-producing bacteria have caused alarm worldwide. Proportion estimates of ESBLEnterobacteriaceae hover around 46% in China, 42% in East Africa, 12% in Germany, and 8% in the United States.CASE SUMMARY The impact of ESBL-producing bacteria on appendiceal abscesses and consequent pelvic abscesses are yet to be examined in depth. A literature review using the search words "appendiceal abscesses" and "ESBL Escherichia coli(E. coli)" revealed very few cases involving ESBL E. coli in any capacity in the context of appendiceal abscesses. This report describes the clinical aspects of a patient with appendicitis whodeveloped a postoperative pelvic abscess infected with ESBL-producing E. coli. In this report, we discuss the risk factors for contracting ESBL E. coli infection in appendicitis and post-appendectomy pelvis abscesses. We also discuss our management approach for postappendectomy ESBL E. coli pelvic abscesses, including drainage, pathogen identification, and pathogen characterisation. When ESBL E. coli is confirmed, carbapenem antibiotics should be promptly administered, as was done efficaciously with this patient. Our report is the first one in a developed country involving ESBL E. coli related surgical complications in association with a routine laparoscopic appendectomy.CONCLUSION Our report is the first involving ESBL E. coli and appendiceal abscesses, and that too consequent to laparoscopic appendectomy.
