An field programmable gate array implementation of an image encryption algorithm based on a discrete chaotic map

Software encryption cannot satisfy real time requirements for multimedia applications which usually involve large volumes of data. To address this problem, an field programmable gate array(FPGA) implementation of the Cyclone EP1C6 for a Kolmogorov chaotic map based image encryption algorithm MASK was proposed. The algorithm was composed of four basic parts: Mixture, key Add, S box and Kolmogorov chaotic map transforms. These parts specifically act on the image as follows: diffusion, applying secret keys, nonlinearity, and permutation. The correlation of adjacent pixels, UACI and the key space of the system subsequently were studied. The source occupation proportion of the hardware was calculated statistically and showed low occupation. Among the advantages of the proposed system are high security, fast encryption speed, and low hardware resources consumption. The proposed system is suitable for implementation in inexpensive FPGA.     

Fast Algorithm of Loads Equalization for Distribution Networks Based on Partition-hierarchical Model

Along with enlargement of scope of distribution, algorithms of reconfiguration for distribution networks become difficult to satisfy real-time require of engineering applications. This paper provides a new algorithm a fast algorithm based on partition-hierarchical model. It is found that partition of loads is relation of the smallest load of vertex that is bigger than average and the biggest load of vertex that is smaller than average. The method reduces the numbers of switches combination by searching smallest load of vertex that is bigger than average and the biggest load of vertex that is smaller than average and realize a fast algorithm of the loads global optimal equalization for distribution networks by transferring the loads. Results of test show that the method presented is applicable and efficient.     

麦秸还田和氮肥运筹对超级杂交稻茎鞘物质运转与籽粒灌浆特性的影响

为探究不同栽培条件和耕作方式对大穗型超级稻籽粒灌浆结实的影响及不同粒位籽粒间差异,寻求超级稻高产优质栽培调控途径。以超级杂交籼稻扬两优6号和II优084为材料,设置麦秸还田和氮肥运筹两因素试验,研究其对茎鞘光合同化物生产、运转及强、弱势粒灌浆特性影响。结果表明,抽穗前麦秸不还田处理(A1)的叶片SPAD值和茎鞘干物质积累量大于麦秸还田处理(A2),抽穗期以后则相反;抽穗前,基蘖肥∶穗肥=7∶3 (B2)的处理叶片SPAD值高于基蘖肥∶穗肥=5∶5 (B1)处理,生育各期茎鞘物质积累量与运转率均为B2大于B1,但干物质积累量抽穗期前差异不大,抽穗与成熟期呈显著与极显著差异;A2与B2互作显著提高生育中后期茎鞘干物质积累量、茎鞘物质输出率与运转率及非结构性碳水化合物(NSC)运转率;强、弱势粒粒重与抽穗至成熟期干物质积累量、抽穗期茎鞘NSC积累量、成熟期干物质量均呈显著正相关,与成熟期NSC积累量呈显著负相关;强、弱势粒的起始灌浆势与抽穗期NSC含量均呈极显著正相关,平均灌浆速率与抽穗期NSC含量及运转率呈显著正相关,强势粒的最大灌浆速率与抽穗期NSC含量及NSC运转率呈显著正相关,弱势粒的最大灌浆速率与NSC运转率呈显著正相关。