借助网间协议变换器,实现了Profibus-DP与Device Net两种异构现场总线协议网络的通信,建成由西门子PCS7作为上位主控系统,由欧姆龙PLC作为下位现场控制子系统的双层监控系统。通过西门子PCS7系统配置,上位级监控程序连续功能图(continuo...借助网间协议变换器,实现了Profibus-DP与Device Net两种异构现场总线协议网络的通信,建成由西门子PCS7作为上位主控系统,由欧姆龙PLC作为下位现场控制子系统的双层监控系统。通过西门子PCS7系统配置,上位级监控程序连续功能图(continuous function chart,CFC)组态,远程监控画面组态,网关PD-100S设置和下位欧姆龙PLC系统配置,将除尘系统纳入电厂主控DCS管控范围。该一体化改造方案所需购置的新设备少,相关软硬件组态及参数设置量小,在现有除尘系统数据更新量下能可靠地实现远程监控。该方案可为异构现场总线系统集成提供参考。展开更多
Soybean is one of the world's most important oil and protein crops. Efficient transformation is a key factor for the improvement of soybean by genetic modification. We describe an optimized protocol for the Agroba...Soybean is one of the world's most important oil and protein crops. Efficient transformation is a key factor for the improvement of soybean by genetic modification. We describe an optimized protocol for the Agrobacterium rhizogenes-mediated transformation of soybean and the induction of hairy root development in vitro. Cotyledons with 0.5-cm hypocotyls were cut from 5-day-old seedlings and used as explants. After infection and co-cultivation,hairy roots were produced in induction culture medium after 10–12 days. Using this method, 90%–99% of the infected explants of five different cultivars produced hairy roots within one month. Observations using reporter constructs showed that 30%–60% of the hairy roots induced were transformed. Based on high transformation efficiency and short transformation period, this method represents an efficient and rapid platform for study of soybean gene function.展开更多
We introduce in this paper cryptographic protocols which use combinatorial group theory. Based on a combinatorial distribution of shares we present secret sharing schemes and cryptosystems using Nielsen transformation...We introduce in this paper cryptographic protocols which use combinatorial group theory. Based on a combinatorial distribution of shares we present secret sharing schemes and cryptosystems using Nielsen transformations. Nielsen transformations are a linear technique to study free groups and general infinite groups. In addition the group of all automorphisms of a free group F, denoted by AUT (F), is generated by a regular Nielsen transformation between two basis of F, and each regular Nielsen transformation between two basis of F defines an automorphism of F.展开更多
Collaborative text editing systems allow multiple users to concurrently edit the same document, which can be modeled by a replicated list object. In the literature, there is a family of operational transformation (OT)...Collaborative text editing systems allow multiple users to concurrently edit the same document, which can be modeled by a replicated list object. In the literature, there is a family of operational transformation (OT)-based Jupiter protocols for replicated lists, including AJupiter, XJupiter, and CJupiter. They are hard to understand due to the subtle OT technique, and little work has been done on formal verification of complete Jupiter protocols. Worse still, they use quite different data structures. It is unclear about how they are related to each other, and it would be laborious to verify each Jupiter protocol separately. In this work, we make contributions towards a better understanding of Jupiter protocols and the relation among them. We first identify the key OT issue in Jupiter and present a generic solution. We summarize several techniques for carrying out the solution, including the data structures to maintain OT results and to guide OTs. Then, we propose an implementation-independent AbsJupiter protocol. Finally, we establish the (data) refinement relation among these Jupiter protocols (AbsJupiter included). We also formally specify and verify the family of Jupiter protocols and the refinement relation among them using TLA+ (TLA stands for"Temporal Logic of Actions") and the TLC model checker. To our knowledge, this is the first work to formally specify and verify a family of OT-based Jupiter protocols and the refinement relation among them. It would be helpful to promote a rigorous study of OT-based protocols.展开更多
文摘借助网间协议变换器,实现了Profibus-DP与Device Net两种异构现场总线协议网络的通信,建成由西门子PCS7作为上位主控系统,由欧姆龙PLC作为下位现场控制子系统的双层监控系统。通过西门子PCS7系统配置,上位级监控程序连续功能图(continuous function chart,CFC)组态,远程监控画面组态,网关PD-100S设置和下位欧姆龙PLC系统配置,将除尘系统纳入电厂主控DCS管控范围。该一体化改造方案所需购置的新设备少,相关软硬件组态及参数设置量小,在现有除尘系统数据更新量下能可靠地实现远程监控。该方案可为异构现场总线系统集成提供参考。
基金supported by the Major Science and Technology Projects of China (2016ZX08010-004)the Ministry of Science and Technology of China (2016YFD0100504)the CAAS (Chinese Academy of Agriculture Sciences) Innovation Project
文摘Soybean is one of the world's most important oil and protein crops. Efficient transformation is a key factor for the improvement of soybean by genetic modification. We describe an optimized protocol for the Agrobacterium rhizogenes-mediated transformation of soybean and the induction of hairy root development in vitro. Cotyledons with 0.5-cm hypocotyls were cut from 5-day-old seedlings and used as explants. After infection and co-cultivation,hairy roots were produced in induction culture medium after 10–12 days. Using this method, 90%–99% of the infected explants of five different cultivars produced hairy roots within one month. Observations using reporter constructs showed that 30%–60% of the hairy roots induced were transformed. Based on high transformation efficiency and short transformation period, this method represents an efficient and rapid platform for study of soybean gene function.
文摘We introduce in this paper cryptographic protocols which use combinatorial group theory. Based on a combinatorial distribution of shares we present secret sharing schemes and cryptosystems using Nielsen transformations. Nielsen transformations are a linear technique to study free groups and general infinite groups. In addition the group of all automorphisms of a free group F, denoted by AUT (F), is generated by a regular Nielsen transformation between two basis of F, and each regular Nielsen transformation between two basis of F defines an automorphism of F.
基金This work was(partially)supported by the National Natural Science Foundation of China under Grant Nos.61690204,61932021,61702253,and 61772258.
文摘Collaborative text editing systems allow multiple users to concurrently edit the same document, which can be modeled by a replicated list object. In the literature, there is a family of operational transformation (OT)-based Jupiter protocols for replicated lists, including AJupiter, XJupiter, and CJupiter. They are hard to understand due to the subtle OT technique, and little work has been done on formal verification of complete Jupiter protocols. Worse still, they use quite different data structures. It is unclear about how they are related to each other, and it would be laborious to verify each Jupiter protocol separately. In this work, we make contributions towards a better understanding of Jupiter protocols and the relation among them. We first identify the key OT issue in Jupiter and present a generic solution. We summarize several techniques for carrying out the solution, including the data structures to maintain OT results and to guide OTs. Then, we propose an implementation-independent AbsJupiter protocol. Finally, we establish the (data) refinement relation among these Jupiter protocols (AbsJupiter included). We also formally specify and verify the family of Jupiter protocols and the refinement relation among them using TLA+ (TLA stands for"Temporal Logic of Actions") and the TLC model checker. To our knowledge, this is the first work to formally specify and verify a family of OT-based Jupiter protocols and the refinement relation among them. It would be helpful to promote a rigorous study of OT-based protocols.
