In recent times, lithium-ion batteries have been widely used owing to their high energy density, extended cycle lifespan, and minimal self-discharge rate. The design of high-speed rechargeable lithium-ion batteries fa...In recent times, lithium-ion batteries have been widely used owing to their high energy density, extended cycle lifespan, and minimal self-discharge rate. The design of high-speed rechargeable lithium-ion batteries faces a significant challenge owing to the need to increase average electric power during charging. This challenge results from the direct influence of the power level on the rate of chemical reactions occurring in the battery electrodes. In this study, the Taguchi optimization method was used to enhance the average electric power during the charging process of lithium-ion batteries. The Taguchi technique is a statistical strategy that facilitates the systematic and efficient evaluation of numerous experimental variables. The proposed method involved varying seven input factors, including positive electrode thickness, positive electrode material, positive electrode active material volume fraction, negative electrode active material volume fraction, separator thickness, positive current collector thickness, and negative current collector thickness. Three levels were assigned to each control factor to identify the optimal conditions and maximize the average electric power during charging. Moreover, a variance assessment analysis was conducted to validate the results obtained from the Taguchi analysis. The results revealed that the Taguchi method was an eff ective approach for optimizing the average electric power during the charging of lithium-ion batteries. This indicates that the positive electrode material, followed by the separator thickness and the negative electrode active material volume fraction, was key factors significantly infl uencing the average electric power during the charging of lithium-ion batteries response. The identification of optimal conditions resulted in the improved performance of lithium-ion batteries, extending their potential in various applications. Particularly, lithium-ion batteries with average electric power of 16 W and 17 W during charging were designed and simulated in the range of 0-12000 s using COMSOL Multiphysics software. This study efficiently employs the Taguchi optimization technique to develop lithium-ion batteries capable of storing a predetermined average electric power during the charging phase. Therefore, this method enables the battery to achieve complete charging within a specific timeframe tailored to a specificapplication. The implementation of this method can save costs, time, and materials compared with other alternative methods, such as the trial-and-error approach.展开更多
The developing market of information technologies i s the most dynamical and thriving business in the modern world. The law of supply and demand establishes repeating, steady cause and effect relation between three ec...The developing market of information technologies i s the most dynamical and thriving business in the modern world. The law of supply and demand establishes repeating, steady cause and effect relation between three economic phenomena-price, supply and demand. Demand is an ideal need and a real opportunity of the customer to buy the goods. Supply is an ideal readiness and a real opportunity of the commodity producer to put the goods on the market . A plethora of factors affect the supply and demand. There is inverse dependenc e between the market price of the goods and the quantity which is in the demand. There is direct dependence between the market price of the goods and the qu antity which is offered to the buyer. The following features distinguish the sof tware from the usual goods in the consumer market: high science intensity, simpl icity of replicating, relative simplicity of modification and updating, high req uirements to quality of the software, at sale the buyer gets it, but it does no t disappear in sale, there is no physical deterioration, but there is a fast ob solescence. To protect the programs against the non-authorized access (the copy ings and operation) technical and legal methods are used: the patent protection, status of industrial secret, license agreements.展开更多
The cultivation of innovative and entrepreneurial capability is a quality requirement of the times for the training of college and university talents. However, the regular teaching system universally has such problems...The cultivation of innovative and entrepreneurial capability is a quality requirement of the times for the training of college and university talents. However, the regular teaching system universally has such problems as much more emphasis on theory than on practice, much more emphasis on inheritance than on innovation, and mismatching between talent training and market demand, so that a great number of graduates do not have enough innovative capacity, and it is very difficult for them to engage in related jobs of software engineering steadily and permanently. By investigating and analyzing similar majors of more than 20 schools at home and abroad, this article proposes a teaching system of talent training of the 3 C-cored major of "innovative and entrepreneurial" software engineering(digital media technology) based on regions, oriented to the industry and marked by school-enterprise linkage, and in connection with the characteristics of college and university education.展开更多
In this paper the authors explore the Global Positioning System （GPS） signal acquisition and tracking algorithms used in software GPS receiver. Acquisition time is the most important parameter in evaluating the perf...In this paper the authors explore the Global Positioning System （GPS） signal acquisition and tracking algorithms used in software GPS receiver. Acquisition time is the most important parameter in evaluating the performance of a software GPS receiver in terms of its speed. A trade-off study is done to seek a good balance between the acquisition accuracy and the processing time. The frequency-domain acquisition method by circular correlation, used in a software GPS receiver, has been improved by studying the power spectrum of the Coarse Acquisition （C/A） code alone. The analysis of C/A code reveals that its power spectrum is symmetrical; hence only half the points are required to perform circular correlation. Besides, either half of the spectrum is asymmetrical where a larger amount of power is concentrated in almost one-quarter of the spectrum on its either sides. This further reduces the number of points used to perform correlation. Comparative results of MATLAB simulation of full-size, half-size and quarter-size circular correlation done on actual data stored on hard disk are provided, and they agree with those obtained using GPS receiver. Further reduction in acquisition time has been achieved by investigating the effect of length of the noncoherent pre-integration period. The improved acquisition methods pave way for further development of new algorithms to enhance software GPS receiver performance.展开更多
AIM To investigate the role of bloodtransfusion in TT viral infection(TTV).METHODS We retrospectively studied serumsamples from 192 transfusion recipients whounderwent cardiovascular surgery and bloodtransfusion betwe...AIM To investigate the role of bloodtransfusion in TT viral infection(TTV).METHODS We retrospectively studied serumsamples from 192 transfusion recipients whounderwent cardiovascular surgery and bloodtransfusion between July 1991 and June 1992.Allpatients had a follow-up every other week for atleast 6 months after transfusion.Eightyrecipients received blood before screeningdonors for hepatitis C antibody(anti-HCV),and112 recipients received screened blood.Recipients with alanine aminotransferase level】2.5 times the upper normal limit were testedfor serological markers for viral hepatitis A,B,C,G,Epstein-Barr virus and cytomegalovirus.TTV infection was defined by the positivity forserum TTV DNA using the polymerase chainreaction method.RESULTS Eleven and three patients,whoreceived anti-HCV unscreened and screened'blood,respectively,had serum ALT levels】90 IU/L.Five patients(HCV and TTV:1;HCV,HGV,and TTV:1;TTV:2;and CMV and TTV:1)were positive for TTV DNA,and four of them hadsero-conversion of TTV DNA.CONCLUSION TTV can be transmitted viablood transfusion.Two recipients infected byTTV alone may be associated with the hepatitis.However,whether TTV was the causal agentremains unsettled,and further studies arenecessary to define the role of TTV infection inchronic hepatitis.展开更多
The tracking, telemetry and command （TT＆C） mission is extremely reliable for its characters of small time horizon and high redundancy. The combined forcing and failure biasing （CFFB） method that is usually used f...The tracking, telemetry and command （TT＆C） mission is extremely reliable for its characters of small time horizon and high redundancy. The combined forcing and failure biasing （CFFB） method that is usually used for simulating the unreliability of the highly dependable mission system seems not so efficient for the TT＆C mission. The concept about the importance of failure transition is proposed based on the logical relationship between TT＆C mission and its involved resources. Then, the importance is used for readjusting the transition rate of the failure transition when using the forcing and failure biasing during the simulation. Examples show that the improved CFFB method can evidently increase the occurrence of the TT＆C mission failure event and decrease the sample variance. More redundancy of the TT＆C mission leads to the improved CFFB method more efficient.展开更多
The whole airspace phased array telemetry,track and command(TT&C)system is regarded as the development tendency of next generation TT&C system,and the distribution of the antenna units and the beamforming tech...The whole airspace phased array telemetry,track and command(TT&C)system is regarded as the development tendency of next generation TT&C system,and the distribution of the antenna units and the beamforming technology have sparked wide interest in this field.A method for antenna distribution is proposed based on the linear subarrays technology.A symmetrical truncated cone conformal array is composed of the linear subarrays placed on the generatrix.The impact of truncated cone bottom radius and elevation angle on beamforming are studied and simulated.Simulation results verify the system design.展开更多
文摘In recent times, lithium-ion batteries have been widely used owing to their high energy density, extended cycle lifespan, and minimal self-discharge rate. The design of high-speed rechargeable lithium-ion batteries faces a significant challenge owing to the need to increase average electric power during charging. This challenge results from the direct influence of the power level on the rate of chemical reactions occurring in the battery electrodes. In this study, the Taguchi optimization method was used to enhance the average electric power during the charging process of lithium-ion batteries. The Taguchi technique is a statistical strategy that facilitates the systematic and efficient evaluation of numerous experimental variables. The proposed method involved varying seven input factors, including positive electrode thickness, positive electrode material, positive electrode active material volume fraction, negative electrode active material volume fraction, separator thickness, positive current collector thickness, and negative current collector thickness. Three levels were assigned to each control factor to identify the optimal conditions and maximize the average electric power during charging. Moreover, a variance assessment analysis was conducted to validate the results obtained from the Taguchi analysis. The results revealed that the Taguchi method was an eff ective approach for optimizing the average electric power during the charging of lithium-ion batteries. This indicates that the positive electrode material, followed by the separator thickness and the negative electrode active material volume fraction, was key factors significantly infl uencing the average electric power during the charging of lithium-ion batteries response. The identification of optimal conditions resulted in the improved performance of lithium-ion batteries, extending their potential in various applications. Particularly, lithium-ion batteries with average electric power of 16 W and 17 W during charging were designed and simulated in the range of 0-12000 s using COMSOL Multiphysics software. This study efficiently employs the Taguchi optimization technique to develop lithium-ion batteries capable of storing a predetermined average electric power during the charging phase. Therefore, this method enables the battery to achieve complete charging within a specific timeframe tailored to a specificapplication. The implementation of this method can save costs, time, and materials compared with other alternative methods, such as the trial-and-error approach.
文摘The developing market of information technologies i s the most dynamical and thriving business in the modern world. The law of supply and demand establishes repeating, steady cause and effect relation between three economic phenomena-price, supply and demand. Demand is an ideal need and a real opportunity of the customer to buy the goods. Supply is an ideal readiness and a real opportunity of the commodity producer to put the goods on the market . A plethora of factors affect the supply and demand. There is inverse dependenc e between the market price of the goods and the quantity which is in the demand. There is direct dependence between the market price of the goods and the qu antity which is offered to the buyer. The following features distinguish the sof tware from the usual goods in the consumer market: high science intensity, simpl icity of replicating, relative simplicity of modification and updating, high req uirements to quality of the software, at sale the buyer gets it, but it does no t disappear in sale, there is no physical deterioration, but there is a fast ob solescence. To protect the programs against the non-authorized access (the copy ings and operation) technical and legal methods are used: the patent protection, status of industrial secret, license agreements.
基金supported by Research and Practice on the reform of graduate education and teaching in Jiangsu Province in 2016(JGZZ16_065)
文摘The cultivation of innovative and entrepreneurial capability is a quality requirement of the times for the training of college and university talents. However, the regular teaching system universally has such problems as much more emphasis on theory than on practice, much more emphasis on inheritance than on innovation, and mismatching between talent training and market demand, so that a great number of graduates do not have enough innovative capacity, and it is very difficult for them to engage in related jobs of software engineering steadily and permanently. By investigating and analyzing similar majors of more than 20 schools at home and abroad, this article proposes a teaching system of talent training of the 3 C-cored major of "innovative and entrepreneurial" software engineering(digital media technology) based on regions, oriented to the industry and marked by school-enterprise linkage, and in connection with the characteristics of college and university education.
文摘In this paper the authors explore the Global Positioning System （GPS） signal acquisition and tracking algorithms used in software GPS receiver. Acquisition time is the most important parameter in evaluating the performance of a software GPS receiver in terms of its speed. A trade-off study is done to seek a good balance between the acquisition accuracy and the processing time. The frequency-domain acquisition method by circular correlation, used in a software GPS receiver, has been improved by studying the power spectrum of the Coarse Acquisition （C/A） code alone. The analysis of C/A code reveals that its power spectrum is symmetrical; hence only half the points are required to perform circular correlation. Besides, either half of the spectrum is asymmetrical where a larger amount of power is concentrated in almost one-quarter of the spectrum on its either sides. This further reduces the number of points used to perform correlation. Comparative results of MATLAB simulation of full-size, half-size and quarter-size circular correlation done on actual data stored on hard disk are provided, and they agree with those obtained using GPS receiver. Further reduction in acquisition time has been achieved by investigating the effect of length of the noncoherent pre-integration period. The improved acquisition methods pave way for further development of new algorithms to enhance software GPS receiver performance.
文摘AIM To investigate the role of bloodtransfusion in TT viral infection(TTV).METHODS We retrospectively studied serumsamples from 192 transfusion recipients whounderwent cardiovascular surgery and bloodtransfusion between July 1991 and June 1992.Allpatients had a follow-up every other week for atleast 6 months after transfusion.Eightyrecipients received blood before screeningdonors for hepatitis C antibody(anti-HCV),and112 recipients received screened blood.Recipients with alanine aminotransferase level】2.5 times the upper normal limit were testedfor serological markers for viral hepatitis A,B,C,G,Epstein-Barr virus and cytomegalovirus.TTV infection was defined by the positivity forserum TTV DNA using the polymerase chainreaction method.RESULTS Eleven and three patients,whoreceived anti-HCV unscreened and screened'blood,respectively,had serum ALT levels】90 IU/L.Five patients(HCV and TTV:1;HCV,HGV,and TTV:1;TTV:2;and CMV and TTV:1)were positive for TTV DNA,and four of them hadsero-conversion of TTV DNA.CONCLUSION TTV can be transmitted viablood transfusion.Two recipients infected byTTV alone may be associated with the hepatitis.However,whether TTV was the causal agentremains unsettled,and further studies arenecessary to define the role of TTV infection inchronic hepatitis.
基金supported by the National Natural Science Foundation of China (71071159)
文摘The tracking, telemetry and command （TT＆C） mission is extremely reliable for its characters of small time horizon and high redundancy. The combined forcing and failure biasing （CFFB） method that is usually used for simulating the unreliability of the highly dependable mission system seems not so efficient for the TT＆C mission. The concept about the importance of failure transition is proposed based on the logical relationship between TT＆C mission and its involved resources. Then, the importance is used for readjusting the transition rate of the failure transition when using the forcing and failure biasing during the simulation. Examples show that the improved CFFB method can evidently increase the occurrence of the TT＆C mission failure event and decrease the sample variance. More redundancy of the TT＆C mission leads to the improved CFFB method more efficient.
文摘The whole airspace phased array telemetry,track and command(TT&C)system is regarded as the development tendency of next generation TT&C system,and the distribution of the antenna units and the beamforming technology have sparked wide interest in this field.A method for antenna distribution is proposed based on the linear subarrays technology.A symmetrical truncated cone conformal array is composed of the linear subarrays placed on the generatrix.The impact of truncated cone bottom radius and elevation angle on beamforming are studied and simulated.Simulation results verify the system design.
