Delay/Disruption-Tolerant Networking(DTN) originated from research on Interplanetary Internet and still today space applications are the most important application field and research stimulus. This paper investigates ...Delay/Disruption-Tolerant Networking(DTN) originated from research on Interplanetary Internet and still today space applications are the most important application field and research stimulus. This paper investigates DTN communications between the Earth and the far side of the Moon, by means of a lunar orbiter acting as relay. After an introductory part, the paper presents a comprehensive analysis of the DTN performance that can be achieved on the identified communication scenario. The focus is on the evaluation of the stateof-the-art ability of Interplanetary Overlay Network(ION), the NASA DTN implementation of Bundle Protocol(BP) and Contact Graph Routing(CGR), to meet the many challenges of the space communication scenario investigated(and more generally of a future interplaynetary Internet): intermittent links, network partitioning, scarce bandwidth, long delays, dynamic routing, handling of high priority and emergency traffic, interoperability issues. A study of security threats and Bundle Security Protocol(BSP) countermeasures complete the work.The many results provided, confirm the essential role of DTN in future space communications.展开更多
This article describes the application of the PIMS software in formulating monthly refining production plan. Application of the PIMS software can help to solve a series of problems related with monthly plan of refinin...This article describes the application of the PIMS software in formulating monthly refining production plan. Application of the PIMS software can help to solve a series of problems related with monthly plan of refining production such as optimized selection of crude and feedstocks, optimized selection of production scale and processing scheme, identification of bottlenecks and their mitigation,optimized selection of turnaround time and optimized selection of operating regime, which have increased the economic benefits of refining enterprises. With the further development and improvement of models the PIMS software will play an increasingly important role in formulating monthly plans of refining operations and production management at refineries. This article also explores the problems existing in refinery monthly planning, and has made recommendations on developing and improving models and reporting system, enhancement of basic data acquisition, model maintenance personnel and staff training.展开更多
文摘Delay/Disruption-Tolerant Networking(DTN) originated from research on Interplanetary Internet and still today space applications are the most important application field and research stimulus. This paper investigates DTN communications between the Earth and the far side of the Moon, by means of a lunar orbiter acting as relay. After an introductory part, the paper presents a comprehensive analysis of the DTN performance that can be achieved on the identified communication scenario. The focus is on the evaluation of the stateof-the-art ability of Interplanetary Overlay Network(ION), the NASA DTN implementation of Bundle Protocol(BP) and Contact Graph Routing(CGR), to meet the many challenges of the space communication scenario investigated(and more generally of a future interplaynetary Internet): intermittent links, network partitioning, scarce bandwidth, long delays, dynamic routing, handling of high priority and emergency traffic, interoperability issues. A study of security threats and Bundle Security Protocol(BSP) countermeasures complete the work.The many results provided, confirm the essential role of DTN in future space communications.
文摘This article describes the application of the PIMS software in formulating monthly refining production plan. Application of the PIMS software can help to solve a series of problems related with monthly plan of refining production such as optimized selection of crude and feedstocks, optimized selection of production scale and processing scheme, identification of bottlenecks and their mitigation,optimized selection of turnaround time and optimized selection of operating regime, which have increased the economic benefits of refining enterprises. With the further development and improvement of models the PIMS software will play an increasingly important role in formulating monthly plans of refining operations and production management at refineries. This article also explores the problems existing in refinery monthly planning, and has made recommendations on developing and improving models and reporting system, enhancement of basic data acquisition, model maintenance personnel and staff training.