In the wireless sensor networks(WSN),the sensor nodes have limited battery life and are deployed in hostile environments.It is very difficult to recharging or replacement of the batteries after deployment for the sens...In the wireless sensor networks(WSN),the sensor nodes have limited battery life and are deployed in hostile environments.It is very difficult to recharging or replacement of the batteries after deployment for the sensor nodes in inaccessible areas.Therefore,how to increase the network lifetime of the WSN is deserved to be studied.In this study,a WSN routing algorithm was proposed based on block clustering and springboard nodes to increase the network lifetime of the WSN.Firstly,by analyzing the influence of communication transmission distance on network energy consumption,block clustering was introduced to control node transmission distance in order to reduce total network energy consumption.In addition,a network transmission model was proposed based on springboard nodes and the advantages of network energy consumption of this model against multi-hop between clusters were analyzed.The simulation results show that,compared with the LEACH algorithm,EECPK-means algorithm and energy centroid clustering algorithm,the proposed routing algorithm effectively prolongs the network lifetime of WSN.展开更多
Long-term planning is one of the most important stages that determines the distribution of cash flows over the mine life and the feasibility of the project. However, it is not feasible in block caving to generate a pr...Long-term planning is one of the most important stages that determines the distribution of cash flows over the mine life and the feasibility of the project. However, it is not feasible in block caving to generate a production schedule that will provide optimal operating strategies without considering geotechnical constraints. This paper develops a mixed-integer linear programming(MILP) model to optimize the extraction sequence of drawpoints over multiple time horizons of block-cave mines with respect to the draw control systems. A multi-similarity index clustering technique to solve the MILP model in a reasonable time is also presented. Application and comparison of production scheduling based on the draw control system and clustering technique are illustrated using 325 drawpoints over 15 periods. The results show a significant reduction in the size of the MILP model, and in the time required to solve it.展开更多
A new no-reference blocking artifact metric for B-DCT compression video is presented in this paper. We first present a new definition of blocking artifact and a new method for measuring perceptive blocking artifact ba...A new no-reference blocking artifact metric for B-DCT compression video is presented in this paper. We first present a new definition of blocking artifact and a new method for measuring perceptive blocking artifact based on HVS taking into account the luminance masking and activity masking characteristic. Then, we propose a new concept of blocking artifact cluster and the algorithm for clustering blocking artifacts. Considering eye movement and fixation, we select several clusters with most serious blocking artifacts and utilize the average of their blocking artifacts to assess the total blocking artifact of B-DCT reconstructed video. Experimental results illustrating the performance of the proposed method are presented and evaluated.展开更多
The syntheses and structures of a novel series of polynuclear coinage metal cluster compounds are discussed. The most fascinating structural characteristic of the Au-Ag alloy clusters with Au_18Ag_19 and Au_18Ag_19 co...The syntheses and structures of a novel series of polynuclear coinage metal cluster compounds are discussed. The most fascinating structural characteristic of the Au-Ag alloy clusters with Au_18Ag_19 and Au_18Ag_19 cores and phosphine ligands, which were prepared by the reduction of mononuclear coinage metal complexes R3PAuX and R3PAgX with NaBH4 in organic solution, is their construction from 13-atom gold-centred icosahedral Au_7Ag_6 building blocks. The structures of the polynuclear coinage metal clusters with R2dtc ligands are variable with either unlimited linear chain or triangular M3 units.展开更多
电动汽车在充电过程中易发生火灾事故,为了提高电动汽车充电站火灾检测实时性,提出一种基于YOLOv4-Tiny-CBAM的电动汽车充电站火焰烟雾多目标实时检测与预警算法:为在低算力平台实现实时检测选用YOLOv4-Tiny轻量级网络模型;引入K-means...电动汽车在充电过程中易发生火灾事故,为了提高电动汽车充电站火灾检测实时性,提出一种基于YOLOv4-Tiny-CBAM的电动汽车充电站火焰烟雾多目标实时检测与预警算法:为在低算力平台实现实时检测选用YOLOv4-Tiny轻量级网络模型;引入K-means-GA算法重新计算锚框值;引入卷积注意力机制模块(convolutional block attention module,CBAM)以加强网络对火焰烟雾特征提取能力以提升检测精度;将电动汽车充电站监控视频作为模型检测输入源,实现就地端实时检测。实验结果表明:该改进算法模型参数量为6.143 M,视频检测每秒传输帧数(frames per second,FPS)值为43,均值平均精度(mean average precision,mAP)值为86.76%,具有较好的目标连续跟踪能力,满足实时检测的需求,对无人化电动汽车充电站安全运行以及火灾应急处置具有重要意义。展开更多
基金National Natural Science Foundation of China(Nos.61661025,61661026)。
文摘In the wireless sensor networks(WSN),the sensor nodes have limited battery life and are deployed in hostile environments.It is very difficult to recharging or replacement of the batteries after deployment for the sensor nodes in inaccessible areas.Therefore,how to increase the network lifetime of the WSN is deserved to be studied.In this study,a WSN routing algorithm was proposed based on block clustering and springboard nodes to increase the network lifetime of the WSN.Firstly,by analyzing the influence of communication transmission distance on network energy consumption,block clustering was introduced to control node transmission distance in order to reduce total network energy consumption.In addition,a network transmission model was proposed based on springboard nodes and the advantages of network energy consumption of this model against multi-hop between clusters were analyzed.The simulation results show that,compared with the LEACH algorithm,EECPK-means algorithm and energy centroid clustering algorithm,the proposed routing algorithm effectively prolongs the network lifetime of WSN.
文摘Long-term planning is one of the most important stages that determines the distribution of cash flows over the mine life and the feasibility of the project. However, it is not feasible in block caving to generate a production schedule that will provide optimal operating strategies without considering geotechnical constraints. This paper develops a mixed-integer linear programming(MILP) model to optimize the extraction sequence of drawpoints over multiple time horizons of block-cave mines with respect to the draw control systems. A multi-similarity index clustering technique to solve the MILP model in a reasonable time is also presented. Application and comparison of production scheduling based on the draw control system and clustering technique are illustrated using 325 drawpoints over 15 periods. The results show a significant reduction in the size of the MILP model, and in the time required to solve it.
文摘针对超密集网络(ultra dense network,UDN)中基站密集部署导致的严重层间干扰问题,构建了考虑频谱复用和共信道干扰条件下最大化系统总吞吐量问题模型,提出了一种基于块坐标下降(block coordinate descent,BCD)法的联合频谱资源优化(joint resource optimization based on BCD,JROBB)方法。该方法将原问题分解为分簇、子信道分配和功率分配三个子问题,通过BCD法迭代优化子信道分配和功率分配,逼近原问题的最优解。仿真分析表明,在复杂度提升有限的情况下,系统总吞吐量比现有典型算法平均至少提升22%,可以有效提升频谱利用率。
基金Project (No. YJCB2003017MU) supported by Huawei Technology Fund, China
文摘A new no-reference blocking artifact metric for B-DCT compression video is presented in this paper. We first present a new definition of blocking artifact and a new method for measuring perceptive blocking artifact based on HVS taking into account the luminance masking and activity masking characteristic. Then, we propose a new concept of blocking artifact cluster and the algorithm for clustering blocking artifacts. Considering eye movement and fixation, we select several clusters with most serious blocking artifacts and utilize the average of their blocking artifacts to assess the total blocking artifact of B-DCT reconstructed video. Experimental results illustrating the performance of the proposed method are presented and evaluated.
文摘The syntheses and structures of a novel series of polynuclear coinage metal cluster compounds are discussed. The most fascinating structural characteristic of the Au-Ag alloy clusters with Au_18Ag_19 and Au_18Ag_19 cores and phosphine ligands, which were prepared by the reduction of mononuclear coinage metal complexes R3PAuX and R3PAgX with NaBH4 in organic solution, is their construction from 13-atom gold-centred icosahedral Au_7Ag_6 building blocks. The structures of the polynuclear coinage metal clusters with R2dtc ligands are variable with either unlimited linear chain or triangular M3 units.
文摘电动汽车在充电过程中易发生火灾事故,为了提高电动汽车充电站火灾检测实时性,提出一种基于YOLOv4-Tiny-CBAM的电动汽车充电站火焰烟雾多目标实时检测与预警算法:为在低算力平台实现实时检测选用YOLOv4-Tiny轻量级网络模型;引入K-means-GA算法重新计算锚框值;引入卷积注意力机制模块(convolutional block attention module,CBAM)以加强网络对火焰烟雾特征提取能力以提升检测精度;将电动汽车充电站监控视频作为模型检测输入源,实现就地端实时检测。实验结果表明:该改进算法模型参数量为6.143 M,视频检测每秒传输帧数(frames per second,FPS)值为43,均值平均精度(mean average precision,mAP)值为86.76%,具有较好的目标连续跟踪能力,满足实时检测的需求,对无人化电动汽车充电站安全运行以及火灾应急处置具有重要意义。
