Geographical Information System (GIS) always plays an integral role in LBS systems. But it comes with technology problems, such as less flexible, low efficiency, no redundancy of existing geographic information of app...Geographical Information System (GIS) always plays an integral role in LBS systems. But it comes with technology problems, such as less flexible, low efficiency, no redundancy of existing geographic information of application configuration which has high entry cost. At same time, indoors positioning is attracting more and more attention from research domain where GPS-like systems do not work. By RSSI location fingerprint data that sampling from the actual WSN environment, this article analyzed RF signal propagation characteristics in indoor from the point of view of the indoor positioning, and analyzed some factors that may affect the positioning error, which provided a theoretical basis for the positioning algorithm design and positioning system deployment. The aim of this paper is also to present a lightweight, efficient and scalable microkernel plug-in geospatial information application system and its implementation method for GIS in LBS design and practice. In this paper a software model called Resource loading manager (RLM) is designed. Through the RLM efficient allocation of geographic information resources and security management could be achieved.展开更多
One of the most important features of modem minor satellites is to realize autonomous moving. The perfomance of the satellite autonomous computer operating system acting as the control center is of utrnost importance....One of the most important features of modem minor satellites is to realize autonomous moving. The perfomance of the satellite autonomous computer operating system acting as the control center is of utrnost importance. The recent trend in operating system development is adopting microkernel architecture that holds such advantages as microminiaturization, modularity, portability and extendibility. IPC is the key of microkernel design. Message-based IPC mechanism is generally used in existing microkernel Operating system. It is of consistency, safety and reliability.However, it can not provide efficient support for real-time applications in satellite systems and it only applies to loose coupling multi-processor architecture. In this paper, an improvement solution for existing message-based IPC is proposed at first to obtain real-time performance. Then a new IPC mechanism is designed. It particulary applies to shared memory tight coupling multi-processor architecture.展开更多
This paper presents the development of a microkernel with a device driver controller for embedded systems. The implementation was done in C language aiming low cost microcontrollers. The proposed system allowed to per...This paper presents the development of a microkernel with a device driver controller for embedded systems. The implementation was done in C language aiming low cost microcontrollers. The proposed system allowed to perform soft real-time activities while keeping the drivers and the application isolated by a secure layer. The callback system proved itself extremely simple to use while still maintaining the security of the system regarding the temporal constraints.展开更多
By contrasting the traditional way in which GIS was completed that comes with less flexible, low efficiency, and lack redundancy which cause high entry cost, the fast development of microkernel plug-in technology prov...By contrasting the traditional way in which GIS was completed that comes with less flexible, low efficiency, and lack redundancy which cause high entry cost, the fast development of microkernel plug-in technology provides the lightweight, efficient and scalable solution to Geographical Information System (GIS). This paper is to reveal the potential of microkernel plug-in geospatial information processing technology in GIS design and practice, with the acceptance and usage of function model called Resource loading manager(RLM) for GIS applications, which provides a possible solution to overcome the GIS’s high cost issue. After the short review of microkernel plug-in technology, the possibility of GIS design with microkernel is analyzed. This paper also introduced the composition of the whole system and the design of GIS service platform based on middle-ware in detail.展开更多
Microkernel OSes separate OS functionalities,including file systems and device drivers,into different userlevel services,which mitigates the problem of lacking isolation in monolithic OSes.Nevertheless,from the perspe...Microkernel OSes separate OS functionalities,including file systems and device drivers,into different userlevel services,which mitigates the problem of lacking isolation in monolithic OSes.Nevertheless,from the perspective of applications,compromised services may still threaten applications’security.Specifically,attackers can utilize vulnerabilities in file systems and disk drivers to leak or manipulate applications’file content.The key problem is that de-privileging OS services from the kernel level to the user level does not mean the reduction of applications’trusted computing base(TCB),and applications still need to trust all the required system services.This paper shows a case for providing the file service to applications with minimum TCB on microkernel OSes.Observing that file services actually do not need to access concrete file content,we propose a mechanism named Mirage,which deprives their privilege of accessing file content while preserving their management capability.Mirage efficiently protects the confidentiality and integrity of application files from untrusted services.The evaluation demonstrates that Mirage outperforms an encryption-based mechanism by up to 128%for IO-intensive workloads.展开更多
This paper explores potential for the RAMpage memory hierarchy to use a microkernel with a small memory footprint, in a specialized cache-speed static RAM （tightly-coupled memory, TCM）. Dreamy memory is DRAM kept in...This paper explores potential for the RAMpage memory hierarchy to use a microkernel with a small memory footprint, in a specialized cache-speed static RAM （tightly-coupled memory, TCM）. Dreamy memory is DRAM kept in low-power mode, unless referenced. Simulations show that a small microkernel suits RAMpage well, in that it achieves significantly better speed and energy gains than a standard hierarchy from adding TCM. RAMpage, in its best 128KB L2 case, gained 11% speed using TCM, and reduced energy 14%. Equivalent conventional hierarchy gains were under 1%. While 1MB L2 was significantly faster against lower-energy cases for the smaller L2, the larger SRAM＇s energy does not justify the speed gain. Using a 128KB L2 cache in a conventional architecture resulted in a best-case overall run time of 2.58s, compared with the best dreamy mode run time （RAMpage without context switches on misses） of 3.34s, a speed penalty of 29%. Energy in the fastest 128KB L2 case was 2.18J vs. 1.50J, a reduction of 31%. The same RAMpage configuration without dreamy mode took 2.83s as simulated, and used 2.393, an acceptable trade-off （penalty under 10%） for being able to switch easily to a lower-energy mode.展开更多
文摘Geographical Information System (GIS) always plays an integral role in LBS systems. But it comes with technology problems, such as less flexible, low efficiency, no redundancy of existing geographic information of application configuration which has high entry cost. At same time, indoors positioning is attracting more and more attention from research domain where GPS-like systems do not work. By RSSI location fingerprint data that sampling from the actual WSN environment, this article analyzed RF signal propagation characteristics in indoor from the point of view of the indoor positioning, and analyzed some factors that may affect the positioning error, which provided a theoretical basis for the positioning algorithm design and positioning system deployment. The aim of this paper is also to present a lightweight, efficient and scalable microkernel plug-in geospatial information application system and its implementation method for GIS in LBS design and practice. In this paper a software model called Resource loading manager (RLM) is designed. Through the RLM efficient allocation of geographic information resources and security management could be achieved.
文摘One of the most important features of modem minor satellites is to realize autonomous moving. The perfomance of the satellite autonomous computer operating system acting as the control center is of utrnost importance. The recent trend in operating system development is adopting microkernel architecture that holds such advantages as microminiaturization, modularity, portability and extendibility. IPC is the key of microkernel design. Message-based IPC mechanism is generally used in existing microkernel Operating system. It is of consistency, safety and reliability.However, it can not provide efficient support for real-time applications in satellite systems and it only applies to loose coupling multi-processor architecture. In this paper, an improvement solution for existing message-based IPC is proposed at first to obtain real-time performance. Then a new IPC mechanism is designed. It particulary applies to shared memory tight coupling multi-processor architecture.
文摘This paper presents the development of a microkernel with a device driver controller for embedded systems. The implementation was done in C language aiming low cost microcontrollers. The proposed system allowed to perform soft real-time activities while keeping the drivers and the application isolated by a secure layer. The callback system proved itself extremely simple to use while still maintaining the security of the system regarding the temporal constraints.
文摘By contrasting the traditional way in which GIS was completed that comes with less flexible, low efficiency, and lack redundancy which cause high entry cost, the fast development of microkernel plug-in technology provides the lightweight, efficient and scalable solution to Geographical Information System (GIS). This paper is to reveal the potential of microkernel plug-in geospatial information processing technology in GIS design and practice, with the acceptance and usage of function model called Resource loading manager(RLM) for GIS applications, which provides a possible solution to overcome the GIS’s high cost issue. After the short review of microkernel plug-in technology, the possibility of GIS design with microkernel is analyzed. This paper also introduced the composition of the whole system and the design of GIS service platform based on middle-ware in detail.
基金supported by the National Natural Science Foundation of China under Grant No.62202292 and research grants from Intel.
文摘Microkernel OSes separate OS functionalities,including file systems and device drivers,into different userlevel services,which mitigates the problem of lacking isolation in monolithic OSes.Nevertheless,from the perspective of applications,compromised services may still threaten applications’security.Specifically,attackers can utilize vulnerabilities in file systems and disk drivers to leak or manipulate applications’file content.The key problem is that de-privileging OS services from the kernel level to the user level does not mean the reduction of applications’trusted computing base(TCB),and applications still need to trust all the required system services.This paper shows a case for providing the file service to applications with minimum TCB on microkernel OSes.Observing that file services actually do not need to access concrete file content,we propose a mechanism named Mirage,which deprives their privilege of accessing file content while preserving their management capability.Mirage efficiently protects the confidentiality and integrity of application files from untrusted services.The evaluation demonstrates that Mirage outperforms an encryption-based mechanism by up to 128%for IO-intensive workloads.
文摘This paper explores potential for the RAMpage memory hierarchy to use a microkernel with a small memory footprint, in a specialized cache-speed static RAM （tightly-coupled memory, TCM）. Dreamy memory is DRAM kept in low-power mode, unless referenced. Simulations show that a small microkernel suits RAMpage well, in that it achieves significantly better speed and energy gains than a standard hierarchy from adding TCM. RAMpage, in its best 128KB L2 case, gained 11% speed using TCM, and reduced energy 14%. Equivalent conventional hierarchy gains were under 1%. While 1MB L2 was significantly faster against lower-energy cases for the smaller L2, the larger SRAM＇s energy does not justify the speed gain. Using a 128KB L2 cache in a conventional architecture resulted in a best-case overall run time of 2.58s, compared with the best dreamy mode run time （RAMpage without context switches on misses） of 3.34s, a speed penalty of 29%. Energy in the fastest 128KB L2 case was 2.18J vs. 1.50J, a reduction of 31%. The same RAMpage configuration without dreamy mode took 2.83s as simulated, and used 2.393, an acceptable trade-off （penalty under 10%） for being able to switch easily to a lower-energy mode.
