Building HVAC equipment installation is vital for indoor comfort,energy efficiency,and environmental quality.Key technologies like vibration control,pipe network alignment,and thermal stress compensation,along with a ...Building HVAC equipment installation is vital for indoor comfort,energy efficiency,and environmental quality.Key technologies like vibration control,pipe network alignment,and thermal stress compensation,along with a multi-faceted quality standards framework,are crucial.Effective process management,practical application analysis,and the integration of robotics,IoT,and AI enhance quality and efficiency.Sustainable development strategies and lifecycle-oriented quality management are also essential for future progress.展开更多
On-site inspection of municipal road subgrade and pavement is of great significance for ensuring the quality,safety,and durability of urban road infrastructure.This paper analyzes its key technologies,introduces non-d...On-site inspection of municipal road subgrade and pavement is of great significance for ensuring the quality,safety,and durability of urban road infrastructure.This paper analyzes its key technologies,introduces non-destructive testing methods such as ground-penetrating radar and ultrasonic testing,elaborates on the multifaceted roles of inspection in engineering construction as well as relevant standards,explores site challenges,key technologies,and corresponding measures,and points out future research directions in intelligent sensing and predictive maintenance.展开更多
Jinping traffic tunnel is one of the deepest traffic tunnels in the world with a maximum overburden of 2 375 m and the overburden over 73% of its total length is larger than 1 500 m. The tunnel is 17.5 km long and des...Jinping traffic tunnel is one of the deepest traffic tunnels in the world with a maximum overburden of 2 375 m and the overburden over 73% of its total length is larger than 1 500 m. The tunnel is 17.5 km long and designed to provide a shortcut road between two hydropower stations： Jinping I and Jinping II of the Jinping Hydropower Project, located on Yalong River, Liangshan State, Sichuan Province, China. The tunnel is so deep that building any shafts is impossible. The construction starts from both ends （east and west ends）, and the construction length from the west end is 10 km with a blind heading. This paper deals with an overview of this project and analysis of the engineering features, as well as key technologies developed and applied during the construction, including geological prediction, rock burst prevention under a super high in-situ stress, sealing of groundwater with a high pressure and big flow rate, ventilation for a blind heading of 10 km, wet spraying of shotcrete at zones of rock burst and rich water, etc. The application of the new technologies to the construction achieved a high quality tunnel within the contract period.展开更多
Hydropower development in China is concentrated in the country's western regions.Among all the rivers in China,the lower course of the Jinsha River contains the richest hydro-energy resource,and therefore,4 mammot...Hydropower development in China is concentrated in the country's western regions.Among all the rivers in China,the lower course of the Jinsha River contains the richest hydro-energy resource,and therefore,4 mammoth hydropower plants are under construction on this particular section of the river at Wudongde,Baihetan,Xiluodu,and Xiangjiaba.The water-blocking structures of the hydropower facilities at Wudongde,Baihetan and Xiluodu are all arch dams of around 300 m high.In view of changes in the geological conditions at the foundation of the Xiluodu dam on the riverbed after excavation started,the designs of expanding foundation surface excavation and dovetailing the dam body and foundation rock on both upstream and downstream sides were introduced,allowing the arch dam and foundation to fit each other and improving the stress conditions of the dam body and foundation.By dividing the dam body into various concrete sections,the dynamic properties of concrete were adequately adjusted to the distribution of stress in the dam body.In addition,the use of the most optimal concrete material and mixture ratio allowed thermodynamics of concrete to satisfy the requirements of the strength,durability,temperature control and crack prevention of the concrete.Moreover,rigorous temperature control measures were introduced to prevent harmful cracking,thus enhancing the integrity of the arch dam.Furthermore,sophisticated construction machinery,scientific testing methods,and sound construction techniques were employed to ensure the uniformity and reliability of concrete placement.The "Digital Dam" for the Xiluodu project,which is based on the theory of total life cycle,has supplied strong support for construction process control and decision-making.展开更多
The microwave photonic technology-based Ultra-Wideband(UWB)Radio over Fiber(RoF)system is an important solution to the future low-cost and high-performance ultra-wideband wireless access network.Much research work has...The microwave photonic technology-based Ultra-Wideband(UWB)Radio over Fiber(RoF)system is an important solution to the future low-cost and high-performance ultra-wideband wireless access network.Much research work has been done in this field with abundant results.This article introduces the RoF system that is based on the all-optical vector modulation technology to further enhance signal’s spectrum efficiency;the full-duplex RoF system that is based on the millimeter wave Phase-Shift Keying(PSK)modulation to greatly simplify base station structure and fiber layout;and the RoF system that is based on multi-service mixed transmission to carry the service with both wired signal and several wireless signals.The article also presents an RoF-based high-definition video transmission platform.展开更多
Purpose–The intelligent Central Traffic Control(CTC)system plays a vital role in establishing an intelligent high-speed railway(HSR)system.As the core of HSR transportation command,the intelligent CTC system is a new...Purpose–The intelligent Central Traffic Control(CTC)system plays a vital role in establishing an intelligent high-speed railway(HSR)system.As the core of HSR transportation command,the intelligent CTC system is a new HSR dispatching command system that integrates the widely used CTC in China with the practical service requirements of intelligent dispatching.This paper aims to propose key technologies and applications for intelligent dispatching command in HSR in China.Design/methodology/approach–This paper first briefly introduces the functions and configuration of the intelligent CTC system.Some new servers,terminals and interfaces are introduced,which are plan adjustment server/terminal,interface for automatic train operation(ATO),interface for Dynamic Monitoring System of Train Control Equipment(DMS),interface for Power Supervisory Control and Data Acquisition(PSCADA),interface for Disaster Monitoring,etc.Findings–The key technologies applied in the intelligent CTC system include automatic adjustment of train operation plans,safety control of train routes and commands,traffic information data platform,integrated simulation of traffic dispatching and ATO function.These technologies have been applied in the Beijing-Zhangjiakou HSR,which commenced operations at the end of 2019.Implementing these key intelligent functions has improved the train dispatching command capacity,ensured the safe operation of intelligent HSR,reduced the labor intensity of dispatching operators and enhanced the intelligence level of China’s dispatching system.Originality/value–This paper provides further challenges and research directions for the intelligent dispatching command of HSR.To achieve the objectives,new measures need to be conducted,including the development of advanced technologies for intelligent dispatching command,coping with new requirements with the development of China’s railway signaling system,the integration of traffic dispatching and train control and the application of AI and data-driven modeling and methods.展开更多
Shale gas resources in the Lower Silurian Longmaxi,southern Sichuan Basin,are huge,where,the geological setting,unlike that in North America,is quite complicated and ground surface infrastructure is poor.Therefore,ada...Shale gas resources in the Lower Silurian Longmaxi,southern Sichuan Basin,are huge,where,the geological setting,unlike that in North America,is quite complicated and ground surface infrastructure is poor.Therefore,adaptable key technologies will be essential to achieve commercial exploitation of shale gas there.In the case study of the Changning-Weiyuan National Shale Gas Demonstration Zone,six series of key techniques were summarized in comprehensive geological evaluation,development optimization,fast and superior drilling of horizontal wells,horizontal-well volumetric fracturing,cluster-well and factory-like operation in well blocks,and highly-efficient and clean exploitation.The above techniques were applied in this field after three rounds of adjustment and optimization,the resulted production rates of shale gas wells were getting higher and higher and the single-well estimated ultimate recovery(EUR)was also rising.Compared with that in the first round,the average EUR of wells in the third round was increased by 128%.In conclusion,the application practices prove that the above series of key techniques with adaptation and flexibility provide a robust technical support for the rapid output of shale gas production in South Sichuan Basin.展开更多
On December 21,2020,The State Council Information Office issued a white paper titled"China's Energy Development in the New Era,"in which the installed capacity of hydropower,wind power,photovoltaic power...On December 21,2020,The State Council Information Office issued a white paper titled"China's Energy Development in the New Era,"in which the installed capacity of hydropower,wind power,photovoltaic power and biomass power generation in China ranked first in the world[1].Solar photovoltaic power generation is the most important development direction of clean energy in the world.It is an important energy strategy to combine it with the field of construction in China.This paper mainly introduces the characteristics and problems of the key technologies of solar photovoltaic building integration,and explores its future development direction and ways,in order to constantly promote the industrialization of new energy technology in China.展开更多
The rapid development of Wireless Local Area Network(WLAN)has not yet broken the bottleneck that the low transmission speed hinders the further development of WLAN.Now,some key technologies for next generation mobile ...The rapid development of Wireless Local Area Network(WLAN)has not yet broken the bottleneck that the low transmission speed hinders the further development of WLAN.Now,some key technologies for next generation mobile communications can solve the problem by supporting high-speed transmission and ensuring reliable performance.IEEE 802.11n has made general amendment to 802.11.Based on IEEE 802.11n,the transmission speed can be doubled by the application of Orthogonal Frequency Division Multiplexing(OFDM)and Multiple Input Multiple Output(MIMO)technologies on the physical layer.In addition,the enhanced Medium Access Control(MAC)system performance,optimized data frame and improved network throughput can all be achieved by the adoption of frame convergence,Transmission Opportunity(TXOP)and block-acknowledge technologies on the MAC layer.A new error correction method,called Low Density Parity Check Code(LDPC),can also be adopted for the receiver to enjoy low Bit Error Ratio(BER)with low S/N,thus improving signal coverage.展开更多
Based on the latest research findings of 3GPP on network sharing,this paper introduces 4 solutions to WCDMA 3G network sharing:site sharing,common network sharing,geographically split network sharing,and radio access ...Based on the latest research findings of 3GPP on network sharing,this paper introduces 4 solutions to WCDMA 3G network sharing:site sharing,common network sharing,geographically split network sharing,and radio access network sharing.It also analyzes the key network sharing technologies,including the lu-Flex function in Release 5,the UTRAN sharing mechanism in the connected mode in Release 5 and the mechanism of network sharing support enhancement in Release 6.展开更多
Ubiquitous sensors, devices, networks, and information are paving the way to smart cities in which computation and intelligence are pervasive. This enables reliable, relevant intormation and services to he accessible ...Ubiquitous sensors, devices, networks, and information are paving the way to smart cities in which computation and intelligence are pervasive. This enables reliable, relevant intormation and services to he accessible to all people. Smart objects, homes, hospitals, manufacturing, and systerns will eventually be present in every city.展开更多
Despite the rapid development in Worldwide Interoperability for Microwave Access(WiMAX)technologies,key technologies for the Physical Layer(PHY)still need to be further improved so as to achieve highly efficient and r...Despite the rapid development in Worldwide Interoperability for Microwave Access(WiMAX)technologies,key technologies for the Physical Layer(PHY)still need to be further improved so as to achieve highly efficient and reliable communication performance,as well as to support a mobile environment with a higher transmisison rate.As an amendment to IEEE 802.16d(for fixed broadband wireless access systems),IEEE 802.16e(for mobile broadband wireless access systems)introduces the Orthogonal Frequency Division Multiplexing(OFDM)and Multiple Input Multiple Output(MIMO)technologies into the PHY,doubling the transmission rate while supporting a certain degree of mobility.In the future,more advanced Air Interface(AI)technology is to be applied in the IEEE 802.16m standard.展开更多
Though the smart city has been one of the hottest fields due to its great potentials to make our world smarter and more efficient with using digital technologies, it is still necessary to clarify what are fundamental ...Though the smart city has been one of the hottest fields due to its great potentials to make our world smarter and more efficient with using digital technologies, it is still necessary to clarify what are fundamental infrastructures and platforms as well as successful practices for truly smart cities. Therefore, the ZTE special issue is focused on key technologies and representative practices in building smart cities. We solicit papers in the topics including but not limited to the following：展开更多
The Yuanba Gasfield is a large gasfield discovered by Sinopec in the Sichuan Basin in recent years,and another main exploration area for natural gas reserves and production increase after the Puguang Gasfield.The ultr...The Yuanba Gasfield is a large gasfield discovered by Sinopec in the Sichuan Basin in recent years,and another main exploration area for natural gas reserves and production increase after the Puguang Gasfield.The ultra-deep sour gas reservoir in the Yuanba Gasfield is characterized by complicated geologic structure,deep reservoirs and complex drilled formation,especially in the continental deep strata which are highly abrasive with low ROP(rate of penetration)and long drilling period.After many years of drilling practice and technical research,the following six key drilling and completion technologies for this type reservoir are established by introducing new tools and technologies,developing specialized drill bits and optimizing drilling design.They are:casing program optimization technology for ROP increasing and safe well completion;gas drilling technology for shallow continental strata and high-efficiency drilling technology for deep high-abrasion continental strata;drillingfluid support technologies of gaseliquid conversion,ultra-deep highly-deviated wells and horizontal-well lubrication and drag reduction,hole stability control and sour gas contamination prevention;well cementing technologies for gas medium,deep-well long cementing intervals and ultra-high pressure small space;horizontal-well trajectory control technologies for measuring instrument,downhole motor opti-mization and bottom hole assembly design;and liner completion modes and completion string optimization technologies suitable for this gas reservoir.Field application shows that these key technologies are contributive to ROP increase and efficiency improvement of 7000 m deep horizontal wells and to significant operational cycle shortening.展开更多
Introduction to HEC Harbin Electric Machinery Company Limited (HEC) is a pivotal company that produces large electric machinery and accessorial control equipment in China. The hydro units made by HEC have
Green building is a manifestation of the response to the national“dual carbon”strategy.With the large-scale promotion of green buildings,the country has successively issued multiple evaluation standards for green bu...Green building is a manifestation of the response to the national“dual carbon”strategy.With the large-scale promotion of green buildings,the country has successively issued multiple evaluation standards for green buildings.Schools are places for preaching,teaching,and solving doubts,and the campus environment plays an important role in improving students’learning efficiency and promoting their physical and mental health.This article is based on the“Green Building Evaluation Standards”GB/T 50378-2019,analyzing and exploring the integration and application of key technologies in green schools,providing reference for green building designers.展开更多
Tiangong space station is a space station independently designed and developed by China.In order to build and operate the space station,it was necessary to make breakthroughs in many fields and master several key tech...Tiangong space station is a space station independently designed and developed by China.In order to build and operate the space station,it was necessary to make breakthroughs in many fields and master several key technologies,which were characterized over a long technological span and underwent difficult verifications.Therefore,in addition to ground verification,on-orbit flight tests of key technologies for the assembly,construction and operation of the space station were planned to be conducted used by the core module,taking into account the differences in the gravity environment between space and the Earth,in order to lay a foundation for the subsequent comprehensive assembly,construction and long-term on-orbit operation of the space station.In this paper,the mission characteristics of the space station are briefly introduced,along with the key technologies for the assembly and construction of the space station,and then the on-orbit verification tests are comprehensively introduced.展开更多
As the mission needs of the autonomous underwater vehicles(AUV) have become increasingly varied and complex,the AUVs are developing in the direction of systematism, multifunction, and clustering technology, which prom...As the mission needs of the autonomous underwater vehicles(AUV) have become increasingly varied and complex,the AUVs are developing in the direction of systematism, multifunction, and clustering technology, which promotes the progress of key technologies and proposes a series of technical problems. Therefore, it is necessary to make systemic analysis and in-depth study for the progress of AUV's key technologies and innovative applications. The multi-functional mission needs and its key technologies involved in complex sea conditions are pointed out through analyzing the domestic and foreign technical programs, functional characteristics and future development plans. Furthermore, the overall design of a multi-moving state AUV is proposed. Then, technical innovations of the key technologies, such as thrust vector, propeller design, kinematics and dynamics, navigation control, and ambient flow field characteristics, are made, combining with the structural characteristics and motion characteristics of the new multi-moving state AUV. The results verify the good performance of the multi-moving state AUV and provide a theoretical guidance and technical support for the design of new AUV in real complex sea conditions.展开更多
This paper presented a new-type CNC curve grinding machine, in order to conquer the disadvantages of conventional NC curve grinding machine and improve surface quality, dimensional accuracy and machining efficiency. T...This paper presented a new-type CNC curve grinding machine, in order to conquer the disadvantages of conventional NC curve grinding machine and improve surface quality, dimensional accuracy and machining efficiency. The new-type grinder adopts some high and new technologies: ① the normal tracing device could make grinding wheel coincide with the normal direction of the machining points in work piece, and improve surface quality and dimensional accuracy; ② the digital image on-line recognition system could monitor machining process and compensate wheel wear in real time; ③ linear motor drive mechanism could realize the exact adjustment of the grinding head digitally and increase the machining efficiency. The math models of normal tracing and circular tolerance zone were presented. The experimental results show that the new-type CNC curve grinding machine equipped with the three devices mentioned above is easy to realize the precision grinding of any complex curve, and improve surface quality, dimensional accuracy and machining efficiency.展开更多
Casting blast can greatly reduce the stripping cost and improve the production capacity of opencast coal mines. Key technologies including high bench blasting, inclined hole, millisecond blasting, pre-splitting blasti...Casting blast can greatly reduce the stripping cost and improve the production capacity of opencast coal mines. Key technologies including high bench blasting, inclined hole, millisecond blasting, pre-splitting blasting and casting blast parameters determination which have influence on the effect of casting blast have been researched with the combination of the ballistic theory and experience in mines. The integrated digital processing system of casting blast was developed in order to simplify the design process of casting blast, improve working efficiency and veracity of design result and comprehensively adopt the software programming method and the theory of casting blast. This system has achieved five functions, namely, the 3D visualization graphics management, the intelligent management of geological information, the intelligent design of casting blast, the analysis and prediction of the blasting effect and the automatic output of the design results. Long-term application in opencast coal mines has shown that research results can not only reduce the specific explosive consumption and improve the blasting effect, but also have high value of popularization and application.展开更多
文摘Building HVAC equipment installation is vital for indoor comfort,energy efficiency,and environmental quality.Key technologies like vibration control,pipe network alignment,and thermal stress compensation,along with a multi-faceted quality standards framework,are crucial.Effective process management,practical application analysis,and the integration of robotics,IoT,and AI enhance quality and efficiency.Sustainable development strategies and lifecycle-oriented quality management are also essential for future progress.
文摘On-site inspection of municipal road subgrade and pavement is of great significance for ensuring the quality,safety,and durability of urban road infrastructure.This paper analyzes its key technologies,introduces non-destructive testing methods such as ground-penetrating radar and ultrasonic testing,elaborates on the multifaceted roles of inspection in engineering construction as well as relevant standards,explores site challenges,key technologies,and corresponding measures,and points out future research directions in intelligent sensing and predictive maintenance.
文摘Jinping traffic tunnel is one of the deepest traffic tunnels in the world with a maximum overburden of 2 375 m and the overburden over 73% of its total length is larger than 1 500 m. The tunnel is 17.5 km long and designed to provide a shortcut road between two hydropower stations： Jinping I and Jinping II of the Jinping Hydropower Project, located on Yalong River, Liangshan State, Sichuan Province, China. The tunnel is so deep that building any shafts is impossible. The construction starts from both ends （east and west ends）, and the construction length from the west end is 10 km with a blind heading. This paper deals with an overview of this project and analysis of the engineering features, as well as key technologies developed and applied during the construction, including geological prediction, rock burst prevention under a super high in-situ stress, sealing of groundwater with a high pressure and big flow rate, ventilation for a blind heading of 10 km, wet spraying of shotcrete at zones of rock burst and rich water, etc. The application of the new technologies to the construction achieved a high quality tunnel within the contract period.
文摘Hydropower development in China is concentrated in the country's western regions.Among all the rivers in China,the lower course of the Jinsha River contains the richest hydro-energy resource,and therefore,4 mammoth hydropower plants are under construction on this particular section of the river at Wudongde,Baihetan,Xiluodu,and Xiangjiaba.The water-blocking structures of the hydropower facilities at Wudongde,Baihetan and Xiluodu are all arch dams of around 300 m high.In view of changes in the geological conditions at the foundation of the Xiluodu dam on the riverbed after excavation started,the designs of expanding foundation surface excavation and dovetailing the dam body and foundation rock on both upstream and downstream sides were introduced,allowing the arch dam and foundation to fit each other and improving the stress conditions of the dam body and foundation.By dividing the dam body into various concrete sections,the dynamic properties of concrete were adequately adjusted to the distribution of stress in the dam body.In addition,the use of the most optimal concrete material and mixture ratio allowed thermodynamics of concrete to satisfy the requirements of the strength,durability,temperature control and crack prevention of the concrete.Moreover,rigorous temperature control measures were introduced to prevent harmful cracking,thus enhancing the integrity of the arch dam.Furthermore,sophisticated construction machinery,scientific testing methods,and sound construction techniques were employed to ensure the uniformity and reliability of concrete placement.The "Digital Dam" for the Xiluodu project,which is based on the theory of total life cycle,has supplied strong support for construction process control and decision-making.
基金supported by the National High Technology Research and Development Program("863"Program)under Grant No.2007AA01Z264 and 2006AA01Z256the National Natural Science Foundation under Grant No.60736002 and 60702006
文摘The microwave photonic technology-based Ultra-Wideband(UWB)Radio over Fiber(RoF)system is an important solution to the future low-cost and high-performance ultra-wideband wireless access network.Much research work has been done in this field with abundant results.This article introduces the RoF system that is based on the all-optical vector modulation technology to further enhance signal’s spectrum efficiency;the full-duplex RoF system that is based on the millimeter wave Phase-Shift Keying(PSK)modulation to greatly simplify base station structure and fiber layout;and the RoF system that is based on multi-service mixed transmission to carry the service with both wired signal and several wireless signals.The article also presents an RoF-based high-definition video transmission platform.
基金This work was supported in part by the National Natural Science Foundation of China under Grant 62203468Young Elite Scientist Sponsorship Program by CAST under Grant 2022QNRC001+1 种基金Foundation of China State Railway Group Co.,Ltd.under Grant K2021X001Foundation of China Academy of Railway Sciences Corporation Limited under Grant 2021YJ315.
文摘Purpose–The intelligent Central Traffic Control(CTC)system plays a vital role in establishing an intelligent high-speed railway(HSR)system.As the core of HSR transportation command,the intelligent CTC system is a new HSR dispatching command system that integrates the widely used CTC in China with the practical service requirements of intelligent dispatching.This paper aims to propose key technologies and applications for intelligent dispatching command in HSR in China.Design/methodology/approach–This paper first briefly introduces the functions and configuration of the intelligent CTC system.Some new servers,terminals and interfaces are introduced,which are plan adjustment server/terminal,interface for automatic train operation(ATO),interface for Dynamic Monitoring System of Train Control Equipment(DMS),interface for Power Supervisory Control and Data Acquisition(PSCADA),interface for Disaster Monitoring,etc.Findings–The key technologies applied in the intelligent CTC system include automatic adjustment of train operation plans,safety control of train routes and commands,traffic information data platform,integrated simulation of traffic dispatching and ATO function.These technologies have been applied in the Beijing-Zhangjiakou HSR,which commenced operations at the end of 2019.Implementing these key intelligent functions has improved the train dispatching command capacity,ensured the safe operation of intelligent HSR,reduced the labor intensity of dispatching operators and enhanced the intelligence level of China’s dispatching system.Originality/value–This paper provides further challenges and research directions for the intelligent dispatching command of HSR.To achieve the objectives,new measures need to be conducted,including the development of advanced technologies for intelligent dispatching command,coping with new requirements with the development of China’s railway signaling system,the integration of traffic dispatching and train control and the application of AI and data-driven modeling and methods.
基金Project supported by the“Changning-Weiyuan Shale Gas Development Demonstration Project”subordinate to the National Major Science and Technology Project“Development of Large Oil/gas Fields and Coalbed Methane”(No.:2016ZX05062)PetroChina Major Science and Technology Project(No.:2016E-0611).
文摘Shale gas resources in the Lower Silurian Longmaxi,southern Sichuan Basin,are huge,where,the geological setting,unlike that in North America,is quite complicated and ground surface infrastructure is poor.Therefore,adaptable key technologies will be essential to achieve commercial exploitation of shale gas there.In the case study of the Changning-Weiyuan National Shale Gas Demonstration Zone,six series of key techniques were summarized in comprehensive geological evaluation,development optimization,fast and superior drilling of horizontal wells,horizontal-well volumetric fracturing,cluster-well and factory-like operation in well blocks,and highly-efficient and clean exploitation.The above techniques were applied in this field after three rounds of adjustment and optimization,the resulted production rates of shale gas wells were getting higher and higher and the single-well estimated ultimate recovery(EUR)was also rising.Compared with that in the first round,the average EUR of wells in the third round was increased by 128%.In conclusion,the application practices prove that the above series of key techniques with adaptation and flexibility provide a robust technical support for the rapid output of shale gas production in South Sichuan Basin.
基金University-level Scientific Research Project of East University of Heilongjiang(Project No.HDFKY210106)。
文摘On December 21,2020,The State Council Information Office issued a white paper titled"China's Energy Development in the New Era,"in which the installed capacity of hydropower,wind power,photovoltaic power and biomass power generation in China ranked first in the world[1].Solar photovoltaic power generation is the most important development direction of clean energy in the world.It is an important energy strategy to combine it with the field of construction in China.This paper mainly introduces the characteristics and problems of the key technologies of solar photovoltaic building integration,and explores its future development direction and ways,in order to constantly promote the industrialization of new energy technology in China.
基金Programs ofNational Natural Science Foundation of China(No.60372048,No.60496316)
文摘The rapid development of Wireless Local Area Network(WLAN)has not yet broken the bottleneck that the low transmission speed hinders the further development of WLAN.Now,some key technologies for next generation mobile communications can solve the problem by supporting high-speed transmission and ensuring reliable performance.IEEE 802.11n has made general amendment to 802.11.Based on IEEE 802.11n,the transmission speed can be doubled by the application of Orthogonal Frequency Division Multiplexing(OFDM)and Multiple Input Multiple Output(MIMO)technologies on the physical layer.In addition,the enhanced Medium Access Control(MAC)system performance,optimized data frame and improved network throughput can all be achieved by the adoption of frame convergence,Transmission Opportunity(TXOP)and block-acknowledge technologies on the MAC layer.A new error correction method,called Low Density Parity Check Code(LDPC),can also be adopted for the receiver to enjoy low Bit Error Ratio(BER)with low S/N,thus improving signal coverage.
文摘Based on the latest research findings of 3GPP on network sharing,this paper introduces 4 solutions to WCDMA 3G network sharing:site sharing,common network sharing,geographically split network sharing,and radio access network sharing.It also analyzes the key network sharing technologies,including the lu-Flex function in Release 5,the UTRAN sharing mechanism in the connected mode in Release 5 and the mechanism of network sharing support enhancement in Release 6.
文摘Ubiquitous sensors, devices, networks, and information are paving the way to smart cities in which computation and intelligence are pervasive. This enables reliable, relevant intormation and services to he accessible to all people. Smart objects, homes, hospitals, manufacturing, and systerns will eventually be present in every city.
文摘Despite the rapid development in Worldwide Interoperability for Microwave Access(WiMAX)technologies,key technologies for the Physical Layer(PHY)still need to be further improved so as to achieve highly efficient and reliable communication performance,as well as to support a mobile environment with a higher transmisison rate.As an amendment to IEEE 802.16d(for fixed broadband wireless access systems),IEEE 802.16e(for mobile broadband wireless access systems)introduces the Orthogonal Frequency Division Multiplexing(OFDM)and Multiple Input Multiple Output(MIMO)technologies into the PHY,doubling the transmission rate while supporting a certain degree of mobility.In the future,more advanced Air Interface(AI)technology is to be applied in the IEEE 802.16m standard.
文摘Though the smart city has been one of the hottest fields due to its great potentials to make our world smarter and more efficient with using digital technologies, it is still necessary to clarify what are fundamental infrastructures and platforms as well as successful practices for truly smart cities. Therefore, the ZTE special issue is focused on key technologies and representative practices in building smart cities. We solicit papers in the topics including but not limited to the following：
文摘The Yuanba Gasfield is a large gasfield discovered by Sinopec in the Sichuan Basin in recent years,and another main exploration area for natural gas reserves and production increase after the Puguang Gasfield.The ultra-deep sour gas reservoir in the Yuanba Gasfield is characterized by complicated geologic structure,deep reservoirs and complex drilled formation,especially in the continental deep strata which are highly abrasive with low ROP(rate of penetration)and long drilling period.After many years of drilling practice and technical research,the following six key drilling and completion technologies for this type reservoir are established by introducing new tools and technologies,developing specialized drill bits and optimizing drilling design.They are:casing program optimization technology for ROP increasing and safe well completion;gas drilling technology for shallow continental strata and high-efficiency drilling technology for deep high-abrasion continental strata;drillingfluid support technologies of gaseliquid conversion,ultra-deep highly-deviated wells and horizontal-well lubrication and drag reduction,hole stability control and sour gas contamination prevention;well cementing technologies for gas medium,deep-well long cementing intervals and ultra-high pressure small space;horizontal-well trajectory control technologies for measuring instrument,downhole motor opti-mization and bottom hole assembly design;and liner completion modes and completion string optimization technologies suitable for this gas reservoir.Field application shows that these key technologies are contributive to ROP increase and efficiency improvement of 7000 m deep horizontal wells and to significant operational cycle shortening.
文摘Introduction to HEC Harbin Electric Machinery Company Limited (HEC) is a pivotal company that produces large electric machinery and accessorial control equipment in China. The hydro units made by HEC have
文摘Green building is a manifestation of the response to the national“dual carbon”strategy.With the large-scale promotion of green buildings,the country has successively issued multiple evaluation standards for green buildings.Schools are places for preaching,teaching,and solving doubts,and the campus environment plays an important role in improving students’learning efficiency and promoting their physical and mental health.This article is based on the“Green Building Evaluation Standards”GB/T 50378-2019,analyzing and exploring the integration and application of key technologies in green schools,providing reference for green building designers.
文摘Tiangong space station is a space station independently designed and developed by China.In order to build and operate the space station,it was necessary to make breakthroughs in many fields and master several key technologies,which were characterized over a long technological span and underwent difficult verifications.Therefore,in addition to ground verification,on-orbit flight tests of key technologies for the assembly,construction and operation of the space station were planned to be conducted used by the core module,taking into account the differences in the gravity environment between space and the Earth,in order to lay a foundation for the subsequent comprehensive assembly,construction and long-term on-orbit operation of the space station.In this paper,the mission characteristics of the space station are briefly introduced,along with the key technologies for the assembly and construction of the space station,and then the on-orbit verification tests are comprehensively introduced.
基金Project(ZR2014EEP019) supported by the Natural Science Foundation of Shandong Province,ChinaProject(51505491) supported by the National Natural Science Foundation of China
文摘As the mission needs of the autonomous underwater vehicles(AUV) have become increasingly varied and complex,the AUVs are developing in the direction of systematism, multifunction, and clustering technology, which promotes the progress of key technologies and proposes a series of technical problems. Therefore, it is necessary to make systemic analysis and in-depth study for the progress of AUV's key technologies and innovative applications. The multi-functional mission needs and its key technologies involved in complex sea conditions are pointed out through analyzing the domestic and foreign technical programs, functional characteristics and future development plans. Furthermore, the overall design of a multi-moving state AUV is proposed. Then, technical innovations of the key technologies, such as thrust vector, propeller design, kinematics and dynamics, navigation control, and ambient flow field characteristics, are made, combining with the structural characteristics and motion characteristics of the new multi-moving state AUV. The results verify the good performance of the multi-moving state AUV and provide a theoretical guidance and technical support for the design of new AUV in real complex sea conditions.
基金Shanghai Science and Technology Foundation of China (No.021111125)
文摘This paper presented a new-type CNC curve grinding machine, in order to conquer the disadvantages of conventional NC curve grinding machine and improve surface quality, dimensional accuracy and machining efficiency. The new-type grinder adopts some high and new technologies: ① the normal tracing device could make grinding wheel coincide with the normal direction of the machining points in work piece, and improve surface quality and dimensional accuracy; ② the digital image on-line recognition system could monitor machining process and compensate wheel wear in real time; ③ linear motor drive mechanism could realize the exact adjustment of the grinding head digitally and increase the machining efficiency. The math models of normal tracing and circular tolerance zone were presented. The experimental results show that the new-type CNC curve grinding machine equipped with the three devices mentioned above is easy to realize the precision grinding of any complex curve, and improve surface quality, dimensional accuracy and machining efficiency.
基金Project supported by the Fundamental Research Funds for the Central Universities,China
文摘Casting blast can greatly reduce the stripping cost and improve the production capacity of opencast coal mines. Key technologies including high bench blasting, inclined hole, millisecond blasting, pre-splitting blasting and casting blast parameters determination which have influence on the effect of casting blast have been researched with the combination of the ballistic theory and experience in mines. The integrated digital processing system of casting blast was developed in order to simplify the design process of casting blast, improve working efficiency and veracity of design result and comprehensively adopt the software programming method and the theory of casting blast. This system has achieved five functions, namely, the 3D visualization graphics management, the intelligent management of geological information, the intelligent design of casting blast, the analysis and prediction of the blasting effect and the automatic output of the design results. Long-term application in opencast coal mines has shown that research results can not only reduce the specific explosive consumption and improve the blasting effect, but also have high value of popularization and application.
