明代漕运总督江一麟在万历初年的任职情况方志记载不一,实由修志者未对其生平仕宦进行核查、未考地名简称及政区沿革等所致.经考可知,江一麟万历二年由浙江左布政使升南赣巡抚,任职期间平定叶楷叛乱,并于万历四年向明廷奏设江西长宁县.万历五年升任漕运总督,万历八年卒于此任.其一生并未任职贵州巡抚,奏设的长宁县亦非四川长宁县.

In space communication environments, most studies in delay tolerant networks (DTNs) adopt experimental approaches and they have shown that the utilization efficiency of link bandwidth can be affected by changing packet sizes at the bundle layer and the convergence layer. However, the lack of theoretical work makes it difficult to find the optimal packet sizes in general scenarios. In this paper, we focus on this important issue by performing a theoretical analysis to solve the packet size optimization problems in both one-hop and multihop DTNs. As our analysis is based on the widely used DTN architecture with Bundle Protocol (BP) and Licklider Transmission Protocol (LTP), the theoretical results can be applied to any DTN scenario using this architecture. We formulate packet size optimization problems in DTNs as nonconvex optimization problems. Furthermore, a goodput enhancement algorithm (GEA) is also proposed to find the optimal packet sizes in order to maximize goodput in DTNs. We conduct numerical analysis as well as simulations to validate our theoretical analysis and study the factors that determine the optimal packet sizes for BP and LTP. Numerical results show that GEA achieves significant performance improvement compared with schemes where packet size optimization on BP and LTP is not jointly considered.

Studies have shown that the size of the transmitted packet has a significant impact on the performance of wireless networks, especially those in challenged environments such as Delay Tolerant Networks (DTNs) where bandwidth is a precious resource. In order to improve the end-to-end goodput in DTNs, segment size at the convergence layer and bundle size at the bundle layer are jointly optimized in this paper. Different from existing work that only performs experimentations to find the optimal packet size in single-hop DTNs, our work focuses on the theoretic analysis and formulates the relationship between packet size at two layers (i.e., the convergence layer and the bundle layer) and the performance metrics (i.e., delay, goodput) of single-hop and multi-hop DTNs. The analysis not only confirms the existence of the optimal packet size, but also quantitatively shows that the optimal packet size is determined by the number of hops, wireless channel conditions in DTNs. Furthermore, a novel Packet Size Optimization Algorithm (PASO) is proposed, in which segment size and bundle size are jointly adjusted to maximize the goodput in multi-hop DTNs. Compared with schemes where joint packet size optimization is not considered, PASO can achieve average 15% more goodput in typical DTN environments where channel conditions are usually assumed to be poor.

Delivery of the application data in delay tolerant network relies on the custody transfer provided by the node storage.Fast release of the occupied node storage is significant for reducing congestion and enhancing network capacity.Studies have shown that the storage efficiency is affected by the size of packet at various network layers.We propose a storage management scheme based on cross-layer packet size optimization,OSUS.OSUS can dynamically adjust Bundle size and the transport layer frame size to maximize the node storage utilization.Simulation results show that,compared with traditional schemes where joint optimization algorithms are not adopted,OSUS can bring 15％ improvement on average in the node storage utilization.