The group-contribution (GC) methods suffer from a limitation concerning to the prediction of process-related indexes, e.g., thermal efficiency. Recently developed analytical models for thermal efficiency of organic Ra...The group-contribution (GC) methods suffer from a limitation concerning to the prediction of process-related indexes, e.g., thermal efficiency. Recently developed analytical models for thermal efficiency of organic Rankine cycles (ORCs) provide a possibility of overcoming the limitation of the GC methods because these models formulate thermal efficiency as functions of key thermal properties. Using these analytical relations together with GC methods, more than 60 organic fluids are screened for medium-low temperature ORCs. The results indicate that the GC methods can estimate thermal properties with acceptable accuracy (mean relative errors are 4.45%-11.50%);the precision, however, is low because the relative errors can vary from less than 0.1% to 45.0%. By contrast, the GC-based estimation of thermal efficiency has better accuracy and precision. The relative errors in thermal efficiency have an arithmetic mean of about 2.9% and fall within the range of 0-24.0%. These findings suggest that the analytical equations provide not only a direct way of estimating thermal efficiency but an accurate and precise approach to evaluating working fluids and guiding computer-aided molecular design of new fluids for ORCs using GC methods.展开更多
A new complementary metal oxide semiconductor UV/blue-extended photodiode was presented for light detection in the UV/blue spectral range. Photoelectric characteristics of this presented photodiode were studied by num...A new complementary metal oxide semiconductor UV/blue-extended photodiode was presented for light detection in the UV/blue spectral range. Photoelectric characteristics of this presented photodiode were studied by numerical modeling and device simulation. Technology computer aided design simulation was done first to analyze its photoelectric characteristics. The structure characteristic and depletion situation of space between two adjacent P+ anodes were discussed. The reverse characteristic, spectral response characteristic and DC characteristic were discussed in detail. For the numerical modeling, dead layer effect is considered in the building of analytical mode. Dead layer is a space in which the boron doping profile decreases towards the surface due to high doping effects and boron redistribution, which affects the sensitivity of photodiode in the UV range seriously. Reverse characteristics and spectral response characteristics were modeled and analyzed typically. At last, silicon test results were given and compared with the simulated result, which shows reasonable match for each.展开更多
Today, more people are riding bicycles than ever before--and the numbers keep growing. This is due in part to a greater awareness of environmental issues and growing health consciousness. Another factor driving the in...Today, more people are riding bicycles than ever before--and the numbers keep growing. This is due in part to a greater awareness of environmental issues and growing health consciousness. Another factor driving the increasing number of women bicyclists today is many designer bicycles now available. Still, these bicycles reflect the subjective sensibilities of their designers, and there is no guarantee that they will always match an increasingly diverse array of consumer values. In response to this challenge, our study sets out to build a bicycle design model based on fashion styles popular with young women in their 20s. Fashion analysis and bicycle design analysis used statistical science, such as cluster analysis, principal component analysis, and analytic hierarchy process （AHP）. After that, we designed a new bicycle using computer-aided design （CAD） from the analysis results. Finally, the approach model developed in this study was confirmed to be effective by an interview with the company.展开更多
Subjected to various stochastic factors, surface mining engineering reliability is difficult to solve by using general reliability mathematical method.The concept of reliability measurement is introduced; And the auth...Subjected to various stochastic factors, surface mining engineering reliability is difficult to solve by using general reliability mathematical method.The concept of reliability measurement is introduced; And the authors have combined system simulation method with CAD technique and developed an interactive color character graphic design system for evaluating and solving the mining engineering reliability in surface mines under the given constraints.展开更多
The present article covers briefly state of the art software interoperability technical solutions and the development of the first module of a new single platform D ＆ A （design ＆ analysis） tool for simulation and ...The present article covers briefly state of the art software interoperability technical solutions and the development of the first module of a new single platform D ＆ A （design ＆ analysis） tool for simulation and prediction of stress and burst behavior of turbine rotating disc a preliminary design stage. This platform singularity requires integration of multiple CAD （computer assisted design） ＆ FEA （finite element analysis） tools processing in batch mode and driven from a SPIE （single platform integration environment）. This first module is also to demonstrate, for an axial turbine disc hub axi-symmetric component, feasibility and usefulness of such a platform at preliminary design stage. Expected benefits of the D ＆ A single platform are to improve output accuracy, reduce cycle time, improve process quality and improve resource productivity.展开更多
The boundary scan architecture and its basic principle of board level built in test(BIT) technology are presented. A design for board level built in test and the method to implement test tool are brought forward.
1 Introduction Erectile dysfunction （ED） and coronary artery disease （CAD） are closely linked, as both conditions share the same cardiovascular risk factors. Indeed, these risk factors can determine endothelial d...1 Introduction Erectile dysfunction （ED） and coronary artery disease （CAD） are closely linked, as both conditions share the same cardiovascular risk factors. Indeed, these risk factors can determine endothelial dysfunction that represents the common underlying mechanism of both ED and CAD. The prevalence of ED is about three-fold higher among diabetic patients than in the general population and a higher prevalence of CAD has been observed in people with diabetes when compared to non-diabetic subjects.Some studies showed that ED can be a powerful marker of silent CAD and a strong predictor of cardiovascular events in apparently uncomplicated type 2 diabetic patients Therefore ED is now considered as a sentinel symptom of silent CAD, as ED often precedes the onset of myocardial ischemia itself by many years.展开更多
A simple calculator for early stage energy performance assessment in residential buildings was developed and partially validated in this study. The calculator is based on the correlation of heat loss and energy need f...A simple calculator for early stage energy performance assessment in residential buildings was developed and partially validated in this study. The calculator is based on the correlation of heat loss and energy need for heating and has fixed internal heat gains as intended for compliance assessment. With the calculator, the effect of any parameter implemented can be immediately seen on delivered and primary energy. Because of simple equations, it is suitable for implementation into CAD （computer aided design） design tools including basic BIM （building information modeling） data. Results showed that the accuracy of the correlation for the cases with practical relevance was not worse than 14% of the energy need of space heating. This applies for passive house insulation level; for less insulated building envelopes, the deviations were smaller. This 14% equals to only 3 kWh/（m2.a）, i.e., the percentage difference in the total delivered and primary energy was much lower because of other components in the energy balance. The deviations determined were implemented in the calculator as safety margin. Results prove that simple energy performance assessment based on specific heat loss coefficient is well justified for early stage energy analyses as well as for compliance assessment implemented in Estonian regulation.展开更多
基金Project(51778626) supported by the National Natural Science Foundation of China
文摘The group-contribution (GC) methods suffer from a limitation concerning to the prediction of process-related indexes, e.g., thermal efficiency. Recently developed analytical models for thermal efficiency of organic Rankine cycles (ORCs) provide a possibility of overcoming the limitation of the GC methods because these models formulate thermal efficiency as functions of key thermal properties. Using these analytical relations together with GC methods, more than 60 organic fluids are screened for medium-low temperature ORCs. The results indicate that the GC methods can estimate thermal properties with acceptable accuracy (mean relative errors are 4.45%-11.50%);the precision, however, is low because the relative errors can vary from less than 0.1% to 45.0%. By contrast, the GC-based estimation of thermal efficiency has better accuracy and precision. The relative errors in thermal efficiency have an arithmetic mean of about 2.9% and fall within the range of 0-24.0%. These findings suggest that the analytical equations provide not only a direct way of estimating thermal efficiency but an accurate and precise approach to evaluating working fluids and guiding computer-aided molecular design of new fluids for ORCs using GC methods.
基金Projects(61233010,61274043)supported by the National Natural Science Foundation of ChinaProject(NCET-11-0975)supported by the Program for New Century Excellent Talents in University,China
文摘A new complementary metal oxide semiconductor UV/blue-extended photodiode was presented for light detection in the UV/blue spectral range. Photoelectric characteristics of this presented photodiode were studied by numerical modeling and device simulation. Technology computer aided design simulation was done first to analyze its photoelectric characteristics. The structure characteristic and depletion situation of space between two adjacent P+ anodes were discussed. The reverse characteristic, spectral response characteristic and DC characteristic were discussed in detail. For the numerical modeling, dead layer effect is considered in the building of analytical mode. Dead layer is a space in which the boron doping profile decreases towards the surface due to high doping effects and boron redistribution, which affects the sensitivity of photodiode in the UV range seriously. Reverse characteristics and spectral response characteristics were modeled and analyzed typically. At last, silicon test results were given and compared with the simulated result, which shows reasonable match for each.
文摘Today, more people are riding bicycles than ever before--and the numbers keep growing. This is due in part to a greater awareness of environmental issues and growing health consciousness. Another factor driving the increasing number of women bicyclists today is many designer bicycles now available. Still, these bicycles reflect the subjective sensibilities of their designers, and there is no guarantee that they will always match an increasingly diverse array of consumer values. In response to this challenge, our study sets out to build a bicycle design model based on fashion styles popular with young women in their 20s. Fashion analysis and bicycle design analysis used statistical science, such as cluster analysis, principal component analysis, and analytic hierarchy process （AHP）. After that, we designed a new bicycle using computer-aided design （CAD） from the analysis results. Finally, the approach model developed in this study was confirmed to be effective by an interview with the company.
文摘Subjected to various stochastic factors, surface mining engineering reliability is difficult to solve by using general reliability mathematical method.The concept of reliability measurement is introduced; And the authors have combined system simulation method with CAD technique and developed an interactive color character graphic design system for evaluating and solving the mining engineering reliability in surface mines under the given constraints.
文摘The present article covers briefly state of the art software interoperability technical solutions and the development of the first module of a new single platform D ＆ A （design ＆ analysis） tool for simulation and prediction of stress and burst behavior of turbine rotating disc a preliminary design stage. This platform singularity requires integration of multiple CAD （computer assisted design） ＆ FEA （finite element analysis） tools processing in batch mode and driven from a SPIE （single platform integration environment）. This first module is also to demonstrate, for an axial turbine disc hub axi-symmetric component, feasibility and usefulness of such a platform at preliminary design stage. Expected benefits of the D ＆ A single platform are to improve output accuracy, reduce cycle time, improve process quality and improve resource productivity.
文摘The boundary scan architecture and its basic principle of board level built in test(BIT) technology are presented. A design for board level built in test and the method to implement test tool are brought forward.
文摘1 Introduction Erectile dysfunction （ED） and coronary artery disease （CAD） are closely linked, as both conditions share the same cardiovascular risk factors. Indeed, these risk factors can determine endothelial dysfunction that represents the common underlying mechanism of both ED and CAD. The prevalence of ED is about three-fold higher among diabetic patients than in the general population and a higher prevalence of CAD has been observed in people with diabetes when compared to non-diabetic subjects.Some studies showed that ED can be a powerful marker of silent CAD and a strong predictor of cardiovascular events in apparently uncomplicated type 2 diabetic patients Therefore ED is now considered as a sentinel symptom of silent CAD, as ED often precedes the onset of myocardial ischemia itself by many years.
文摘A simple calculator for early stage energy performance assessment in residential buildings was developed and partially validated in this study. The calculator is based on the correlation of heat loss and energy need for heating and has fixed internal heat gains as intended for compliance assessment. With the calculator, the effect of any parameter implemented can be immediately seen on delivered and primary energy. Because of simple equations, it is suitable for implementation into CAD （computer aided design） design tools including basic BIM （building information modeling） data. Results showed that the accuracy of the correlation for the cases with practical relevance was not worse than 14% of the energy need of space heating. This applies for passive house insulation level; for less insulated building envelopes, the deviations were smaller. This 14% equals to only 3 kWh/（m2.a）, i.e., the percentage difference in the total delivered and primary energy was much lower because of other components in the energy balance. The deviations determined were implemented in the calculator as safety margin. Results prove that simple energy performance assessment based on specific heat loss coefficient is well justified for early stage energy analyses as well as for compliance assessment implemented in Estonian regulation.
