While wormholes are just as good a prediction of Einstein’s theory as black holes, they are subject to severe restrictions from quantum field theory. To allow for the possibility of interstellar travel, a macroscopic...While wormholes are just as good a prediction of Einstein’s theory as black holes, they are subject to severe restrictions from quantum field theory. To allow for the possibility of interstellar travel, a macroscopic wormhole would need to maintain sufficiently low radial tidal forces. It is proposed in this paper that the assumption of zero tidal forces, i.e., the limiting case, is sufficient for overcoming the restrictions from quantum field theory. The feasibility of this approach is subsequently discussed by 1) introducing the additional conditions needed to ensure that the radial tidal forces can indeed be sufficiently low and 2) by viewing traversable wormholes as emergent phenomena, thereby increasing the likelihood of their existence.展开更多
Under the assumptions of triangular cross section channel and uniform stable flow, an analytical solution of the minimum ecological in-stream flow requirement （MEIFR） is deduced. Based on the analytical solution, th...Under the assumptions of triangular cross section channel and uniform stable flow, an analytical solution of the minimum ecological in-stream flow requirement （MEIFR） is deduced. Based on the analytical solution, the uncertainty of the wetted perimeter method is analyzed by comparing the two techniques for the determination of the critical point on the relationship curve between wetted perimeter, P and discharge, Q. It is clearly shown that the results of MEIFR based on curvature technique （corresponding to the maximum curvature） and slope technique （slope being 1） are significantly different. On the P-Q curve, the slope of the critical point with the maximum curvature is 0.39 and the MEIFR varied prominently with the change of the slope threshold. This indicates that if a certain value of the slope threshold is not available for slope technique, curvature technique may be a better choice. By applying the analytical solution of MEIFR in the losing rivers of the Western Route South-to-North Water Transfer Project in China, the MEIFR value via curvature technique is 2.5%-23.7% of the multi-year average annual discharge, while that for slope technique is 11%-105.7%. General conclusions would rely on the more detailed research for all kinds of cross-sections.展开更多
In this paper the conception of theoretical determine the relations between material experimental characteristics is presented. On the base of stress-strain relations for nonlinear elastic anisotropic material and geo...In this paper the conception of theoretical determine the relations between material experimental characteristics is presented. On the base of stress-strain relations for nonlinear elastic anisotropic material and geometrical interpretation of deformation state, the general form of strain energy density function was introduced. Using this function and variational methods the relations between material characteristics were achieved. All considerations are illustrated by a short theoretical example.展开更多
Testing the parts of mechanical products and ensuring their accuracy to the design requirements are essential to products’ quality, market competitiveness and manufacturers’ maximum economical benefits from these pr...Testing the parts of mechanical products and ensuring their accuracy to the design requirements are essential to products’ quality, market competitiveness and manufacturers’ maximum economical benefits from these products. One of the latest subjects of study in the area of precision measurement is the testing of parts to follow the relative requirements, viz. design requirements for the size tolerance of size features and related geometrical tolerances of the central feature, including the envelope requirement, maximum material requirement and least material requirement. The article analyzes test methods for parts to follow the envelope requirement or maximum material requirement, as well as further requirements of geometrical tolerances for its central feature. The method is effective in improving product quality and rejecting unqualified parts.展开更多
Customer requirements analysis is the key step for product variety design of mass customiza-tion(MC). Quality function deployment (QFD) is a widely used management technique for understanding the voice of the customer...Customer requirements analysis is the key step for product variety design of mass customiza-tion(MC). Quality function deployment (QFD) is a widely used management technique for understanding the voice of the customer (VOC), however, QFD depends heavily on human subject judgment during extracting customer requirements and determination of the importance weights of customer requirements. QFD pro-cess and related problems are so complicated that it is not easily used. In this paper, based on a general data structure of product family, generic bill of material (GBOM), association rules analysis was introduced to construct the classification mechanism between customer requirements and product architecture. The new method can map customer requirements to the items of product family architecture respectively, accomplish the mapping process from customer domain to physical domain directly, and decrease mutual process between customer and designer, improve the product design quality, and thus furthest satisfy customer needs. Finally, an example of customer requirements mapping of the elevator cabin was used to illustrate the proposed method.展开更多
It is well known that there is abundant water resources in basin of the Yangtze River, the first largest river in China, which is mainly located in Southern China. However, water resources is very scarce in the basin ...It is well known that there is abundant water resources in basin of the Yangtze River, the first largest river in China, which is mainly located in Southern China. However, water resources is very scarce in the basin of the Yellow River, which is mainly located in Northern China. So the western route project of south-north water transfer scheme （WRP-SNWTS） aims to transfer water from the Yangtze River to the Yellow River. The area of WRP-SNWT, located in the upper reaches of the Yangtze River and the main areas of Sichuan and the marginal areas of the Qinghai-Tibet Plateau, has sufficient water resources but fragile ecology and environment. Therefore, it is necessary for WRP-SNWT to analyze the ecology water required. Based on the planning principles of from low elevation to high elevation, from small to large, from short to long and from easy to difficulty, the WRP-SNWT will be constructed through three stage projects. The western route first stage project of the south-north water transfer scheme （WRFST-SNWTS） is planned to transfer 4×10^9m^3/a from six tributaries of the Yalong river and from Dadu river to Jiaqu of Yellow River.. Daqu river and Niqu river are the branches of Xianshui river. Sequ river, Duke river, Make river and Ake river are the branches of Dadu river, which account for 65-70% of the total river run-off. It need more research and the rest run-off can satisfy channel ecology water required. According to analysis ecological water required which mainly satisfy for aquicolous biology in water-exporting region, such as low air temperature. Fish and aquicolous biology main living from May to August, and rivers are iced up from December to March of next year, ecology water required mainly for fish and aquicolous biology. The flow criterion of Tennant method is modified. The ecology water required of WRFSP-SNWTS is estimated by the flow data of Zhuwo gauging station, Zhuba gauging station, Chuosijia gauging station and Zumuzu gauging station. The result show that the ecology water required calculated by modified Tennant less 1 l percent than that of Tennant. This estimating result can supply more water resources for transferring to Yellow River. Meanwhile, this can supply gist for research transferring water of WRFSP-SNWTS.展开更多
From the author, there are not less than a dozen of rather significant recent publications in scientific editions anticipating some aspects of importance to innovation such as “bigger data”, AI, IP, and frontier tec...From the author, there are not less than a dozen of rather significant recent publications in scientific editions anticipating some aspects of importance to innovation such as “bigger data”, AI, IP, and frontier technology with a central massive contribution in 2020 on AI, IP, and EI. Nonetheless, the IP associated with AI remains still barely covered in scientific publications. Especially patent discussion tends to be rather a legal matter. Another trilogy, 2013, “Business Strategy-IP Strategy-R&D Strategy: An All-in-One Business Model” proposed by the author, marked the advent, and customized implementation of a new strategy level. After the two trilogies’ volumes, the AI-IP “accessibility” chapter was a logical step brought to the attention of a larger public by the author. The time now to bring to light another chapter, namely the IP eligibility of AI innovation steps in ad hoc inventions. The main objectives of this short, principally illustrated communication, are to: 1) Revise the best mode requirement status, i.e. the best way to enable the reproducibility of claimed matter, reviewing its need for improvement when AI is involved. And proposing a unique sequence of evolution inspired by IP’s current and evolving practices. 2) Give a new dimension to visual aids to help the Best Mode description, demystify AI complexity, and underline frontier traits that may hinder a confident adoption or well-argued rejection. 3) Further illustrations take into account the fact that IoT, AI, and 3D can be simpler than perceived. 4) Finally ATA©, Adjacent Technology Analysis, is timely refreshed in a unique challenging, indeed tumultuous, environment. 5) Bias, such as semantic ones is consistently monitored. 6) Overall leaving space for innovative pleasurable interpretation. The emphasis is on educational, illustrative and demonstrative value.展开更多
Pulverized coal injection（PCI） is a key technology in modern ironmaking by blast furnace（BF） and the life of injection lance has a great influence on PCI operation and on normal running of blast furnace.It is foun...Pulverized coal injection（PCI） is a key technology in modern ironmaking by blast furnace（BF） and the life of injection lance has a great influence on PCI operation and on normal running of blast furnace.It is found that the main reasons for the failure of the lances are their outer surface oxidation and the inner surface erosion through monitoring some lances used in BF.The outer surface oxidation of the lances made of lCr18Ni9Ti is inevitable under high hot blast temperature condition through thermodynamics analysis.A mathematical model for calculating the temperature of common monocular coal lance had been developed according to the principles of mass and energy balance.Increasing temperature and flow velocity of the hot blast would cause a rise in the lance temperature.The influence of hot blast temperature is more obvious.The lance temperature would decline when compressed air flux increases.Conveying technology of dense phase pulverized coal is beneficial to extending lance’s life because decreasing solid-gas ratio would intensify erosion and burning loss.The anti-oxidation temperature of lance materials needs to be over 1000 ℃ for BF intensified smelting.In order to increase the resistance to oxidation of the coal lance’s outer surface,oxidation-resistant steel or Al coating stainless steel is the appropriate material for BF use.Employing the metal surface treatment technology to enhance the hardness of the coal lance’s internal surface could prolong the service life of coal lance展开更多
It is an inevitable trend of sustainable manufacturing to replace flood and dry machining with minimum quantity lubrication(MQL)technology.Nevertheless,for aeronautical difficult-tomachine materials,MQL couldn’t meet...It is an inevitable trend of sustainable manufacturing to replace flood and dry machining with minimum quantity lubrication(MQL)technology.Nevertheless,for aeronautical difficult-tomachine materials,MQL couldn’t meet the high demand of cooling and lubrication due to high heat generation during machining.Nano-biolubricants,especially non-toxic carbon group nano-enhancers(CGNs)are used,can solve this technical bottleneck.However,the machining mechanisms under lubrication of CGNs are unclear at complex interface between tool and workpiece,which characterized by high temperature,pressure,and speed,limited its application in factories and necessitates in-depth understanding.To fill this gap,this study concentrates on the comprehensive quantitative assessment of tribological characteristics based on force,tool wear,chip,and surface integrity in titanium alloy and nickel alloy machining and attempts to answer mechanisms systematically.First,to establish evaluation standard,the cutting mechanisms and performance improvement behavior covering antifriction,antiwear,tool failure,material removal,and surface formation of MQL were revealed.Second,the unique film formation and lubrication behaviors of CGNs in MQL turning,milling,and grinding are concluded.The influence law of molecular structure and micromorphology of CGNs was also answered and optimized options were recommended by considering diverse boundary conditions.Finally,in view of CGNs limitations in MQL,the future development direction is proposed,which needs to be improved in thermal stability of lubricant,activity of CGNs,controllable atomization and transportation methods,and intelligent formation of processing technology solutions.展开更多
文摘While wormholes are just as good a prediction of Einstein’s theory as black holes, they are subject to severe restrictions from quantum field theory. To allow for the possibility of interstellar travel, a macroscopic wormhole would need to maintain sufficiently low radial tidal forces. It is proposed in this paper that the assumption of zero tidal forces, i.e., the limiting case, is sufficient for overcoming the restrictions from quantum field theory. The feasibility of this approach is subsequently discussed by 1) introducing the additional conditions needed to ensure that the radial tidal forces can indeed be sufficiently low and 2) by viewing traversable wormholes as emergent phenomena, thereby increasing the likelihood of their existence.
基金National Natural Science Foundation of China, No. 90211007 No.50279049+1 种基金 Knowledge Innovation Project of IGSNRR, CAS, No.CXIOG-A04-12 No.CX10G-E01-08
文摘Under the assumptions of triangular cross section channel and uniform stable flow, an analytical solution of the minimum ecological in-stream flow requirement （MEIFR） is deduced. Based on the analytical solution, the uncertainty of the wetted perimeter method is analyzed by comparing the two techniques for the determination of the critical point on the relationship curve between wetted perimeter, P and discharge, Q. It is clearly shown that the results of MEIFR based on curvature technique （corresponding to the maximum curvature） and slope technique （slope being 1） are significantly different. On the P-Q curve, the slope of the critical point with the maximum curvature is 0.39 and the MEIFR varied prominently with the change of the slope threshold. This indicates that if a certain value of the slope threshold is not available for slope technique, curvature technique may be a better choice. By applying the analytical solution of MEIFR in the losing rivers of the Western Route South-to-North Water Transfer Project in China, the MEIFR value via curvature technique is 2.5%-23.7% of the multi-year average annual discharge, while that for slope technique is 11%-105.7%. General conclusions would rely on the more detailed research for all kinds of cross-sections.
文摘In this paper the conception of theoretical determine the relations between material experimental characteristics is presented. On the base of stress-strain relations for nonlinear elastic anisotropic material and geometrical interpretation of deformation state, the general form of strain energy density function was introduced. Using this function and variational methods the relations between material characteristics were achieved. All considerations are illustrated by a short theoretical example.
文摘Testing the parts of mechanical products and ensuring their accuracy to the design requirements are essential to products’ quality, market competitiveness and manufacturers’ maximum economical benefits from these products. One of the latest subjects of study in the area of precision measurement is the testing of parts to follow the relative requirements, viz. design requirements for the size tolerance of size features and related geometrical tolerances of the central feature, including the envelope requirement, maximum material requirement and least material requirement. The article analyzes test methods for parts to follow the envelope requirement or maximum material requirement, as well as further requirements of geometrical tolerances for its central feature. The method is effective in improving product quality and rejecting unqualified parts.
基金the National Natural Science Founda-tion of China (No. 70471022)the NSFC / Hong KongResearch Grant Council (No. 70418013)
文摘Customer requirements analysis is the key step for product variety design of mass customiza-tion(MC). Quality function deployment (QFD) is a widely used management technique for understanding the voice of the customer (VOC), however, QFD depends heavily on human subject judgment during extracting customer requirements and determination of the importance weights of customer requirements. QFD pro-cess and related problems are so complicated that it is not easily used. In this paper, based on a general data structure of product family, generic bill of material (GBOM), association rules analysis was introduced to construct the classification mechanism between customer requirements and product architecture. The new method can map customer requirements to the items of product family architecture respectively, accomplish the mapping process from customer domain to physical domain directly, and decrease mutual process between customer and designer, improve the product design quality, and thus furthest satisfy customer needs. Finally, an example of customer requirements mapping of the elevator cabin was used to illustrate the proposed method.
文摘It is well known that there is abundant water resources in basin of the Yangtze River, the first largest river in China, which is mainly located in Southern China. However, water resources is very scarce in the basin of the Yellow River, which is mainly located in Northern China. So the western route project of south-north water transfer scheme （WRP-SNWTS） aims to transfer water from the Yangtze River to the Yellow River. The area of WRP-SNWT, located in the upper reaches of the Yangtze River and the main areas of Sichuan and the marginal areas of the Qinghai-Tibet Plateau, has sufficient water resources but fragile ecology and environment. Therefore, it is necessary for WRP-SNWT to analyze the ecology water required. Based on the planning principles of from low elevation to high elevation, from small to large, from short to long and from easy to difficulty, the WRP-SNWT will be constructed through three stage projects. The western route first stage project of the south-north water transfer scheme （WRFST-SNWTS） is planned to transfer 4×10^9m^3/a from six tributaries of the Yalong river and from Dadu river to Jiaqu of Yellow River.. Daqu river and Niqu river are the branches of Xianshui river. Sequ river, Duke river, Make river and Ake river are the branches of Dadu river, which account for 65-70% of the total river run-off. It need more research and the rest run-off can satisfy channel ecology water required. According to analysis ecological water required which mainly satisfy for aquicolous biology in water-exporting region, such as low air temperature. Fish and aquicolous biology main living from May to August, and rivers are iced up from December to March of next year, ecology water required mainly for fish and aquicolous biology. The flow criterion of Tennant method is modified. The ecology water required of WRFSP-SNWTS is estimated by the flow data of Zhuwo gauging station, Zhuba gauging station, Chuosijia gauging station and Zumuzu gauging station. The result show that the ecology water required calculated by modified Tennant less 1 l percent than that of Tennant. This estimating result can supply more water resources for transferring to Yellow River. Meanwhile, this can supply gist for research transferring water of WRFSP-SNWTS.
文摘From the author, there are not less than a dozen of rather significant recent publications in scientific editions anticipating some aspects of importance to innovation such as “bigger data”, AI, IP, and frontier technology with a central massive contribution in 2020 on AI, IP, and EI. Nonetheless, the IP associated with AI remains still barely covered in scientific publications. Especially patent discussion tends to be rather a legal matter. Another trilogy, 2013, “Business Strategy-IP Strategy-R&D Strategy: An All-in-One Business Model” proposed by the author, marked the advent, and customized implementation of a new strategy level. After the two trilogies’ volumes, the AI-IP “accessibility” chapter was a logical step brought to the attention of a larger public by the author. The time now to bring to light another chapter, namely the IP eligibility of AI innovation steps in ad hoc inventions. The main objectives of this short, principally illustrated communication, are to: 1) Revise the best mode requirement status, i.e. the best way to enable the reproducibility of claimed matter, reviewing its need for improvement when AI is involved. And proposing a unique sequence of evolution inspired by IP’s current and evolving practices. 2) Give a new dimension to visual aids to help the Best Mode description, demystify AI complexity, and underline frontier traits that may hinder a confident adoption or well-argued rejection. 3) Further illustrations take into account the fact that IoT, AI, and 3D can be simpler than perceived. 4) Finally ATA©, Adjacent Technology Analysis, is timely refreshed in a unique challenging, indeed tumultuous, environment. 5) Bias, such as semantic ones is consistently monitored. 6) Overall leaving space for innovative pleasurable interpretation. The emphasis is on educational, illustrative and demonstrative value.
基金Sponsored by National Natural Science Foundation of China(50901054)Hubei Provincial Natural Science Foundation of China(2009CDB401)
文摘Pulverized coal injection（PCI） is a key technology in modern ironmaking by blast furnace（BF） and the life of injection lance has a great influence on PCI operation and on normal running of blast furnace.It is found that the main reasons for the failure of the lances are their outer surface oxidation and the inner surface erosion through monitoring some lances used in BF.The outer surface oxidation of the lances made of lCr18Ni9Ti is inevitable under high hot blast temperature condition through thermodynamics analysis.A mathematical model for calculating the temperature of common monocular coal lance had been developed according to the principles of mass and energy balance.Increasing temperature and flow velocity of the hot blast would cause a rise in the lance temperature.The influence of hot blast temperature is more obvious.The lance temperature would decline when compressed air flux increases.Conveying technology of dense phase pulverized coal is beneficial to extending lance’s life because decreasing solid-gas ratio would intensify erosion and burning loss.The anti-oxidation temperature of lance materials needs to be over 1000 ℃ for BF intensified smelting.In order to increase the resistance to oxidation of the coal lance’s outer surface,oxidation-resistant steel or Al coating stainless steel is the appropriate material for BF use.Employing the metal surface treatment technology to enhance the hardness of the coal lance’s internal surface could prolong the service life of coal lance
基金supported by the National Natural Science Foundation of China(Nos.51975305 and 51905289)the Major Research Project of Shandong Province(No.2019GGX104040)+2 种基金the Major Science and Technology Innovation Engineering Projects of Shandong Province(No.2019JZZY020111)the Natural Science Foundation of Shandong Province(Nos.ZR2020KE027 and ZR2020ME158)the Applied Basic Research Youth Project of Qingdao science and technology plan(No.19-6-2-63-cg)。
文摘It is an inevitable trend of sustainable manufacturing to replace flood and dry machining with minimum quantity lubrication(MQL)technology.Nevertheless,for aeronautical difficult-tomachine materials,MQL couldn’t meet the high demand of cooling and lubrication due to high heat generation during machining.Nano-biolubricants,especially non-toxic carbon group nano-enhancers(CGNs)are used,can solve this technical bottleneck.However,the machining mechanisms under lubrication of CGNs are unclear at complex interface between tool and workpiece,which characterized by high temperature,pressure,and speed,limited its application in factories and necessitates in-depth understanding.To fill this gap,this study concentrates on the comprehensive quantitative assessment of tribological characteristics based on force,tool wear,chip,and surface integrity in titanium alloy and nickel alloy machining and attempts to answer mechanisms systematically.First,to establish evaluation standard,the cutting mechanisms and performance improvement behavior covering antifriction,antiwear,tool failure,material removal,and surface formation of MQL were revealed.Second,the unique film formation and lubrication behaviors of CGNs in MQL turning,milling,and grinding are concluded.The influence law of molecular structure and micromorphology of CGNs was also answered and optimized options were recommended by considering diverse boundary conditions.Finally,in view of CGNs limitations in MQL,the future development direction is proposed,which needs to be improved in thermal stability of lubricant,activity of CGNs,controllable atomization and transportation methods,and intelligent formation of processing technology solutions.
