STUDY OF ROLLING FORCE DISTRIBUTION ALONG THE ROLLING OF PAIR CROSS MILL

The theory of three-dimensional deformation is used.Based on rigid plastic assumption, the theory of stick friction and the sheet crown curve at the entry and the exit are used. The mathematical analytical formula of the rolling force in lateral distribution is deriven.

A Remark on Pl Type Interpolation on Non-Uniformly Distributed Nodes on the Unit Circle

In this paper we study the problem of explicit representation and convergence of Pal type （0;1） interpolation and its converse, with some additional conditions, on the non-uniformly distributed nodes on the unit circle obtaIned by projecting the interlaced zeros of Pn （x） and Pn′ （x） on the unit circle. The motivation to this problem can be traced to the recent studies on the regularity of Birkhoff interpolation and Pal type interpolations on non-uniformly distributed zeros on the unit circle.

考虑极端灾害下系统韧性约束的气电联合配网分布鲁棒扩展规划

近年来,在未来多能互补、综合能源系统的背景下,气电联合配网得到迅速的发展。然而,当前全球各地极端灾害频发,给能源系统的安全性带来了严峻的挑战。针对极端灾害对系统造成的失负荷影响,为兼顾系统的经济性与安全性,提出了一种考虑极端灾害下系统韧性约束的气电联合配网分布鲁棒扩展规划模型。首先,以规划成本与运行成本最小化为目标,建立考虑电动汽车充电站、分布式燃气机组和储能设备的气电联合配网扩展规划模型;然后,考虑极端灾害的作用,建立考虑韧性约束的气电联合配网分布鲁棒扩展规划模型,该模型包括基础场景与极端灾害最坏场景,其中基础场景考虑系统的经济性,以规划成本与基础场景运行成本最小为目标,极端灾害最坏场景则通过韧性约束保证系统的安全性,所提模型通过主问题–子问题迭代求解。最后,算例仿真发现:通过增加电动汽车充电站、分布式燃气机组和储能设备的规划投建,系统的经济性得到明显提升;而在面对极端灾害的影响下,通过分布式燃气机组的发电和电动汽车、储能设备的放电,系统失负荷情况得到减少,但随着系统韧性的增大所需单位规划成本会大幅增加。本文为在规划层面提升系统韧性提供了一种有效与实用的方法,为未来减小极端灾害对系统造成的影响的方案提供了一定参考。

Local structure of calcium silicate melts from classical molecular dynamics simulation and a newly constructed thermodynamic model

The distributions of local structural units of calcium silicate melts were quantified by means of classical molecular dynamics simulation and a newly constructed structural thermodynamic model. The distribution of five kinds of Si-O tetrahedra Qi from these two methods was compared with each other and also with the experimental Raman spectra, an excellent agreement was achieved. These not only displayed the panorama distribution of microstructural units in the whole composition range, but also proved that the thermodynamic model is suitable for the utilization as the subsequent application model of spectral experiments for the thermodynamic calculation. Meanwhile, the five refined regions mastered by different disproportionating reactions were obtained. Finally, the distributions of two kinds of connections between Qi were obtained, denoted as Qi-Ca-Qj and Qi-[Ob]-Qj, from the thermodynamic model, and a theoretical verification was given that the dominant connections for any composition are equivalent connections.

考虑风电不确定性的分布鲁棒机会约束机组组合模型

风电渗透率的不断提高大大减少了化石燃料的消耗和温室气体的排放,但风电输出功率的不确定性和间歇性,使传统机组组合问题的解决方法不可行。在此背景下,为了描述风力发电的不确定性,首先,引入一个基于矩信息的椭球式模糊集,并将机会约束运用到机组组合模型中,将功率平衡约束变为软约束;其次,运用分布鲁棒优化方法,将机组组合问题通过线性化方法重构为混合整数线性规划(MILP)问题;并提出限定模糊集中的分布具有单峰性及分时段设定置信度的值的2种改进方法,提高模型的经济性,最后,通过案例分析和仿真结果验证模型与方法的实用性和可行性。

Mechanism of Fast Data Retransmission in CU-DU Split Architecture of 5G NRG

The 5G radio access network （RAN） architectm＇e is supposed to be split into the central unit （CU） and the distributed unit （DU） in order to support more flexible transport networks and provide enhanced user experience. However, such functional split may also introduce some new technical issues. In this pa- per, we study the data fast retransmission issue introduced by this functional split in different scenarios and solutions are provided to handle this issue. With the fast data retransmis- sion mechanism proposed in this paper, the retransmitted da- ta packets could be identified and handled with high priority. In this way, the data delivery between the CU and DU in 5G RAN is assured.

基于KL散度的含储能机组组合分布鲁棒优化方法

为应对风电场出力的波动性和随机性给机组组合带来的问题,提出了基于Kullback-Leibler(KL)散度的含储能机组组合的两阶段分布鲁棒优化模型。在电池储能的运行模型的基础,将电池储能模型嵌入到传统的火电机组组合模型中,建立了含储能的机组组合两阶段优化模型;基于KL散度构建了风电场出力的模糊集,形成了含储能机组组合的两阶段分布鲁棒优化模型,通过对偶变换和广义Benders分解将其转化成易于求解的混合整数凸优化模型进行求解。通过IEEE RTS 24节点系统仿真结果表明,所提出的分布鲁棒优化方法保守性优于鲁棒优化方法,经济性接近随机优化方法,且随着KL散度增大,机组组合成本缓慢增加。

Symbol RFID Technology to be Deployed at United States Defense Logistics Agency's Distribution Centers Worldwide

Symbol Technologies, Inc., The Enterprise Mobility Company, today announced that it had been selected by ODIN technologies, the leader in the physics of RFID testing, software and deployment, to support its recent contract win with the United States Defense Logistics Agency (DLA), the United States Department of Defense’s (DoD) logistics combat support agency that provides supplies and services to America’s military forces worldwide.

A review of stabilization methods for DCMG with CPL,the role of bandwidth limits and droop control

DC microgrids(DCMGs)integrate and coordinate various DC distribution generation units including various renew-able energy sources and battery storage systems,and have been used in satellites,the International Space Station,telecom power stations,computer power supplies,electric aircraft,and electric ships.However,the presence of constant power loads(CPLs)can cause instability in DCMGs.Thus,this paper reviews the stabilization techniques that can resolve instability caused by CPLs,as well as various parameters of CPLs,such as bandwidth,and the frequency of the CPLs that can stabilize the DCMGs.It also discusses recent trends and future work in finding stability limits using the parameters of CPLs.It should be useful for directing research towards appropriate mathematical and experimental approaches for the stability of DCMGs with CPLs.