A novel adaptive joint power control algorithm with channel estimation in a CDMA cellular system

Joint power control has advantages of multi-user detection and power control; and it can combat the multi-access interference and the near-far problem. A novel adaptive joint power control algorithm with channel estimation in a CDMA cellular system was designed. Simulation results show that the algorithm can control the power not only quickly but also precisely with a time change. The method is useful for increasing system capacity.

An Anisotropic Geomechanical Model for Jointed Rock Masses at Taishan Nuclear Power Station, Southern China

An anisotropic geomechanical model for jointed rock mass is presented. Simultaneously with deriving the orthotropic anisotropy elastic parameters along the positive axis, the equivalent compliance matrix for the deflection axis orthotropic anisotropy was derived through a three- dimensional coordinate transformation. In addition, Singh＇s analysis of the stress concentration effects of intermittent joints was adopted, based on two groups of intermittent joints and a set of cross- cutting joints in the jointed rock mass. The stress concentration effects caused by intermittent joints and the coupling effect of cross-cutting joints along the deflection-axis are also considered. The proposed anisotropic mechanics parameters method is applied to determine the deformation parameters of jointed granite at the Taishan Nuclear Power Station. Combined with the deterministic mechanical parameters of rock blocks and joints, the deformation parameters and their variability in jointed rock masses are estimated quantitatively. The computed results show that jointed granite at the Taishan Nuclear Power Station exhibits typical anisotropic mechanical characteristics; the elastic moduli in the two horizontal directions were similar, but the elastic modulus in the vertical direction was much greater. Jointed rock elastic moduli in the two horizontal and vertical directions were respectively about 24% and 37% of the core of rock, showing weakly orthotropic anisotropy; the ratio of elastic moduli in the vertical and horizontal directions was 1.53, clearly indicating the transversely isotropic rock mass mechanical characteristics. The method can be popularized to solve other rock mechanics problems in nuclear power engineering.

An Approach of Distributed Joint Optimization for Cluster-based Wireless Sensor Networks

Wireless sensor networks (WSNs) are energyconstrained, so energy saving is one of the most important issues in typical applications. The clustered WSN topology is considered in this paper. To achieve the balance of energy consumption and utility of network resources, we explicitly model and factor the effect of power and rate. A novel joint optimization model is proposed with the protection for cluster head. By the mean of a choice of two appropriate sub-utility functions, the distributed iterative algorithm is obtained. The convergence of the proposed iterative algorithm is proved analytically. We consider general dual decomposition method to realize variable separation and distributed computation, which is practical in large-scale sensor networks. Numerical results show that the proposed joint optimal algorithm converges to the optimal power allocation and rate transmission, and validate the performance in terms of prolonging of network lifetime and improvement of throughput. © 2014 Chinese Association of Automation.

iPAS:A deep Monte Carlo Tree Search-based intelligent pilot-power allocation scheme for massive MIMO system

Massive Multiple-Input-Multiple-Output(MIMO)is a promising technology to meet the demand for the connection of massive devices and high data capacity for mobile networks in the next generation communication system.However,due to the massive connectivity of mobile devices,the pilot contamination problem will severely degrade the communication quality and spectrum efficiency of the massive MIMO system.We propose a deep Monte Carlo Tree Search(MCTS)-based intelligent Pilot-power Allocation Scheme(iPAS)to address this issue.The core of iPAS is a multi-task deep reinforcement learning algorithm that can automatically learn the radio environment and make decisions on the pilot sequence and power allocation to maximize the spectrum efficiency with self-play training.To accelerate the searching convergence,we introduce a Deep Neural Network(DNN)to predict the pilot sequence and power allocation actions.The DNN is trained in a self-supervised learning manner,where the training data is generated from the searching process of the MCTS algorithm.Numerical results show that our proposed iPAS achieves a better Cumulative Distribution Function(CDF)of the ergodic spectral efficiency compared with the previous suboptimal algorithms.

改善实时Joint变换相关输出效果的研究

利用Joint变换的相关性质,可实现实时图象识别。本文提出一种功率谱处理方法,可对实时相关输出中的直流分量和噪声进行抑制,以增强相关信号,提高信噪比。计算机模拟实验的结果表明,这种方法很有效。

Joint Transceiver Designs for Full-Duplex MIMO SWIPT Systems Based on MSE Criterion

For the simultaneous wireless information and power transfer(SWIPT), the full-duplex MIMO system can achieve simultaneous transmission of information and energy more efficiently than the half-duplex. Based on the mean-square-error(MSE) criterion, the optimization problem of joint transceiver design with transmitting power constraint and energy harvesting constraint is formulated. Next, by semidefinite relaxation(SDR) and randomization method, the SDRbased scheme is proposed. In order to reduce the complexity, the closed-form scheme is presented with some simplified measures. Robust beamforming is then studied considering the practical condition. The simulation results such as MSE versus signal-noise-ratio(SNR), MSE versus the iteration number, well prove the performance of the proposed schemes for the system model.

Effects of salinity on the nail-holding power of dimension lumber used in light-frame wood building

We studied the effect of salinity on nail-hold- ing power in wood construction. In saline solution, the holding power of nails was less than in purified water. With the increase of salt concentration, the surface and side nail- holding power of the wood specimens both declined, but the differences between salinity treatments were not sig- nificant. However, compared to the surface and side nail- holding power, the power on the edge was generally less and the difference was not obvious in different salt con- centrations. In the same salt concentration, with the extension of the processing cycle, the performance of holding power of nails showed a downward trend, expect the temporary rise in the middle.

含分布式电源和电动汽车的配电网可靠性评估

针对目前大规模分布式电源和电动汽车接入配电网后,给配电网可靠性带来一定影响的问题,提出了一种含有分布式电源和电动汽车的新型配电网的可靠性评估方法。首先,考虑到风光出力的不确定性和相关性,选择拟合性最优的Frank-Copula函数,建立了风光联合出力概率模型。其次,分析了电动汽车用户行为特征,提出了基于动态分时电价的电动汽车有序充放电控制策略。最后,基于改进IEEE-RBTS Bus6测试系统的主馈线F4,对系统的可靠性指标进行计算分析,结果表明所提的风光联合出力模型和有序充放电控制策略可以有效降低对配电网可靠性的影响。

基于TOPSIS-Shapley值法的梯级水电站补偿效益分摊研究

针对流域内联合电站数目众多但利益分配存在纠纷的情况,旨在提出一种更为合理的梯级电站利益分配方法。基于Shapley值法和TOPSIS法,综合考虑电站贡献及电站对不同客观分摊方法的相对满意程度,建立TOPSIS-Shapley值法梯级电站补偿效益分摊模型,同时为解决Shapley值法在求解多利益主体梯级电站联合调度增益分配问题中的局限性,引入聚合降维思想。模型思路如下:将上游电站联合调度前后梯级发电效益的增量作为补偿效益,首先采取四种不同的客观分摊方法对电站特性参数指标进行计算,构成TOPSIS的基础决策矩阵,利用TOPSIS原理得出电站对各个分摊方法的相对满意度,同时采用联盟博弈理论,计算电站所有可能联盟方式下的发电效益,得到基于Shapley值的补偿效益分摊结果,最后将TOPSIS原理得出的分摊系数与由Shapley值法所得的分摊系数结合形成综合分摊权重,应用于黑河上游的八级电站补偿效益分摊中。工程应用实例表明:该方法不仅考虑了联盟电站对整体的边际贡献和各电站的分摊满意程度,且兼顾了电站的特性指标差异,合理量化和分配了各电站间的发电补偿效益,分摊结果公平合理、易被各方接受,可促进流域各级电站参与联合调度从而达到整体效益最大的目标,对于数量较多的梯级水电站补偿效益分配问题具有重要参考意义。

基于多任务渐进式学习模型的风-光-荷功率短期预测

同一地区的风电、光伏和负荷功率与风速、辐照度和温度等气象因素密切相关,在电力系统不同运行场景下存在一定的互动耦合关系。为了捕获多源荷间的差异性和相关性,挖掘高维数据中蕴含的潜在规律,提出一种基于深度时空融合网络的多任务渐进式学习模型,实现风-光-荷联合功率预测。首先,基于深度时空融合网络设计共享信息与特有信息子网;然后,构建计及时空相关性的多任务渐进式学习模型,分别对风、光、荷功率的共享和特有时空信息进行由浅至深渐进式提取;最后,将共享信息与特有信息子网所得特征向量进行融合映射,实现对未来风-光-荷功率的联合预测。实际日前风-光-荷联合预测算例结果表明,所提模型可弥补现有多任务模型出现“负迁移”和“跷跷板”现象的不足,提高预测精度和稳健性。

尺骨茎突修复与否对桡骨远端骨折合并尺骨茎突骨折的疗效评价

目的评价尺骨茎突修复与否对桡骨远端骨折合并尺骨茎突骨折患者术后功能的影响。方法回顾性随访2020年10月-2021年10月入院的48例桡骨远端骨折合并尺骨茎突骨折患者,分为固定组和非固定组各24例,固定组在桡骨远端骨折固定基础上进行尺骨茎突修复手术,非固定组进行桡骨远端骨折固定。对比固定组和非固定组术后8周掌倾角、尺偏角、桡骨高度、腕关节背伸和屈曲及前臂旋转活动范围,术后12个月Gartland-Werley腕关节评估结果和愈合率。结果尺骨茎突骨折固定组和非固定组对患者腕部功能、前臂活动范围、愈合率的影响差异无统计学意义(P>0.05),但两组Gartland-Werley评分中残余畸形和客观评分项差异具有统计学意义(P<0.05),推测可能是三角纤维软骨撕裂与否对尺骨茎突骨折有影响。结论尺骨茎突骨折修复与否对桡骨远端骨折合并尺骨茎突骨折术后愈合能力不具有统计学意义,对于腕关节和前臂功能均无明显影响。

Structural Characteristics and Mechanical Properties of Rock Mass in the Field of Tianwan Nuclear Power Plant, China

The structural characteristics and mechanical properties of the rock mass are important parts of the feasibility study on the nuclear power engineering field. In this study, by means of in situ investigation and statistics, the structural plane and joint fissure features of the rock mass were analyzed and discussed at different plots and different depth scopes in the Tianwan Nuclear Power engineering field, the rock mass integrality and its weathered degree were evaluated respectively, and especially, the unfavorable geological phenomena of strongly-weathered cystid existing in the field were studied. According to the results of indoor rock mechanical tests, in combination with drilling, the shallow seismic prospecting, sonic logging and point load tests, the statistical results of physical and mechanical indices of rocks at key plots of the field were analyzed, and the design parameters of the field were calculated. It provided scientific basis for the foundation design of the nuclear power plant.

基于二维动态减载和双层MPC的风储联合调频与功率优化分配

风机可以通过减载控制提供调频备用功率,但存在弃风量大的问题。为此,结合储能装置,设计了考虑风速分区与储能荷电状态(SOC)的二维动态减载策略,在提供充足调频备用功率的同时减小了弃风功率。在此基础上,结合双层模型预测控制(MPC)架构,提出了计及机组转矩波动的风储联合调频控制策略,上层MPC将风电场视作整体,通过协调风储出力提升调频效果;下层MPC通过风电场内的功率优化分配以抑制机组的转矩波动,保证调频性能的同时提高了机组运行稳定性。通过仿真分析验证了所提策略的有效性,结果表明该减载策略具有更高的风能利用率,且在调频过程中通过机组的功率优化分配减小了机组的转矩波动,提高了机组运行稳定性。

Unequal decoding power allocation for efficient video transmission

We present an unequal decoding power allocation （UDPA） approach for minimization of the receiver power consumption subject to a given quality of service （QoS）, by exploiting data partitioning and turbo decoding. We assign unequal decoding power of forward error correction （FEC） to data partitions with different priority by jointly considering the source coding, channel coding and receiver power consumption. The proposed scheme is applied to H.264 video over additive white Gaussion noise （AWGN） channel, and achieves excellent tradeoff between video delivery quality and power consumption, and yields significant power saving compared with the conventional equal decoding power allocation （EDPA） approach in wireless video transmission.

基于FL的无蜂窝网络用户调度与功率分配策略

为解决无蜂窝网络系统中用户链路质量差异和通信、计算资源占用不平衡导致的联邦学习(FL)训练性能受限问题,设计了一个联合用户调度和功率分配的优化方案。首先,提出了一种低复杂度的基于资源优先的二次抽样用户调度(RPSS-US)算法,根据用户计算资源的可用性和链路质量选择用户,优先调度对系统容量和全局模型更新贡献较大的用户参与FL任务,提高整体训练性能。随后,提出了一种基于二分法的功率分配(BM-PA)算法,通过优化功率分配改善用户链路质量差异,以提高数据传输速率,减少FL任务的总体时延。通过交替迭代优化这2个子问题,实现系统性能的联合优化。仿真结果表明,相较于其他对比算法,所提出的算法下行吞吐量提升了47.19%,上行吞吐量提升了22.60%,FL任务时间消耗减少了57.33%,并在达到相同模型精度时的时间开销最小。

燃料电池增程式动力系统能量管理策略研究

以某款纯电动客车为研究对象,以增加车辆续驶里程为目的,提出燃料电池增程式混合动力系统结构,根据性能指标对动力系统各部件进行匹配计算和选型.提出了开关/功率跟随式能量管理策略,基于Cruise和Simulink分别搭建了整车动力系统模型和燃料电池及能量管理策略模型并进行联合仿真.结果表明,采用文中提出的能量管理策略车辆经济性相对于开关式和能量跟随式两种控制策略分别提高62%和31%,续驶里程相对于该两种控制策略分别提高41%和18%.

前景理论视角下废旧动力电池回收监管演化博弈分析

废旧动力电池具有较强的负外部性,违背了新能源汽车设计的初衷。为促进废旧动力电池有效回收,将前景理论与演化博弈论耦合,综合考虑政府、企业(汽车生产)和公众之间的利益,促使政府和公众对企业进行共同监督,构建三方博弈模型。针对初始意愿、罚款组成、风险态度系数和损失规避系数的不同情况,进行模拟数值仿真,并结合现实中废旧动力电池的认识度、奖惩机制和盈利信心进行分析。研究表明:提高公众或政府的初始监督意愿,可以促进企业回收废旧动力电池;当企业的回收策略为亏损时,提高企业对公众的补偿金额、降低企业的风险态度系数和损失规避系数,可以促进企业积极回收;在废旧动力电池回收过程中,共同监督的效果优于单独监督。

土工膜与沥青混凝土结构新型接头模型试验研究

为研究土工膜与沥青混凝土结构之间的接头连接方式,基于室内模型试验,从土工膜与沥青混凝土之间的粘结强度、接头适应变形能力、接头防渗性能3个方面论证土工膜与沥青混凝土面板接头的可靠性,提出了土工膜与沥青混凝土结构新型接头连接方式。结果表明:采用SK手刮聚脲将土工膜粘贴至沥青混凝土上,粘结的强度随环境温度降低而升高,5℃时,粘结强度可达到1.0 MPa;通过在接头部位设置鼓包,可以吸收接头变形;HDPE膜与沥青混凝土连接板的接头可以适应上下错动7.8 cm+张开5 cm+剪切7.2 cm的位移;施加变形后对接头进行抗渗试验,接头在0.45 MPa的水压力下可以保持防渗性能。采用SK手刮聚脲将土工膜与沥青混凝土直接粘结,采取合理的施工工艺可保证接头连接的可靠性和适应性,对推广土工膜防渗具有积极意义。

风光火储联合供应火电厂厂用电系统优化调度

随着风电和光伏发电量逐年增长,其消纳问题日益凸显。同时,大容量火电机组厂用电负荷也相对较高,造成额外的运行成本。对此,基于多能互补思想,建立了一种风光火储联合供应火电厂厂用电优化调度模型。首先,提出了风光火储联合供应火电厂厂用电的组成结构,将风电、光伏发电优先供应厂用电负荷;其次构建了风光火储联合供应火电厂厂用电优化调度模型,考虑了火电机组不同负荷率下的运行成本和风光储成本,采用层次分析法建立了基于总成本、弃风弃光成本和环境成本的多目标函数,设置相应约束条件;最后,设置不同的场景对比分析联合供应厂用电系统的优化结果,试验结果表明:所提出的联合供应厂用电系统模型可以减少机组运行成本和环境成本,并促进风光消纳。

山东半岛附近海域风、浪能资源联合评估

采用ERA5风场驱动第三代浅海海浪数值模式(SWAN),构建山东半岛附近海域波浪模型,得到30 a同步风浪数据,对海上风能和波浪能进行联合评估。评估分析海上风能和波浪能的能源潜力、稳定性及两种资源的相关性、互补性,可为未来风浪资源联合开发提供依据。研究结果表明,该海域风能和波浪能资源丰富,有明显的季节变化特征,冬季资源最为丰富且稳定性较高。两种资源在近岸海域的互补性更强,在渤海西部和黄海北部的近岸海域相关性相对较低,具有更高的联合开发潜力。