Yolk–Shell MnO@ZnMn2O4/N–C Nanorods Derived from α‐MnO2/ZIF‐8 as Anode Materials for Lithium Ion Batteries

Manganese oxides (MnO_x) are promising anode materials for lithium ion batteries, but they generally exhibit mediocre performances due to intrinsic low ionic conductivity, high polarization, and poor stability. Herein, yolk–shell nanorods comprising of nitrogen‐doped carbon (N–C) coating on manganese monoxide (MnO) coupled with zinc manganate (ZnMn₂O₄) nanoparticles are manufactured via one‐step carbonization of α‐MnO₂/ZIF‐8 precursors. When evaluated as anodes for lithium ion batteries, MnO@ZnMn₂O₄/N–C exhibits an reversible capacity of 803 mAh g^?1 at 50 mA g^?1 after 100 cycles, excellent cyclability with a capacity of 595 mAh g^?1 at 1000 mAg^?1 after 200 cycles, as well as better rate capability compared with those non‐N–C shelled manganese oxides (MnO_x). The outstanding electrochemical performance is attributed to the unique yolk–shell nanorod structure, the coating effect of N–C and nanoscale size.     

TD-LTE系统中基于FPGA的解调与解扰的仿真和实现

基于FPGA实现TD-LTE系统中的解调与解扰。包括解调与解扰的介绍、max-log-map算法的介绍、方案的构成、FPGA实现流程以及实现结果分析。在Virtex-6芯片上进行了仿真、综合、板级验证。实现结果表明,该解调与解扰算法应用到TD-LTE射频一致性测试仪表中具有良好的高效性和可靠性。     

Auto-tuning Similarity Search Algorithms on Multi-core Architectures

In recent times, large high-dimensional datasets have become ubiquitous. Video and image repositories, financial, and sensor data are just a few examples of such datasets in practice. Many applications that use such datasets require the retrieval of data items similar to a given query item, or the nearest neighbors (NN or $k$ -NN) of a given item. Another common query is the retrieval of multiple sets of nearest neighbors, i.e., multi $k$ -NN, for different query items on the same data. With commodity multi-core CPUs becoming more and more widespread at lower costs, developing parallel algorithms for these search problems has become increasingly important. While the core nearest neighbor search problem is relatively easy to parallelize, it is challenging to tune it for optimality. This is due to the fact that the various performance-specific algorithmic parameters, or “tuning knobs”, are inter-related and also depend on the data and query workloads. In this paper, we present (1) a detailed study of the various tuning knobs and their contributions on increasing the query throughput for parallelized versions of the two most common classes of high-dimensional multi-NN search algorithms: linear scan and tree traversal, and (2) an offline auto-tuner for setting these knobs by iteratively measuring actual query execution times for a given workload and dataset. We show experimentally that our auto-tuner reaches near-optimal performance and significantly outperforms un-tuned versions of parallel multi-NN algorithms for real video repository data on a variety of multi-core platforms.     

A localization method for the Internet of Things

Many localization algorithms and systems have been developed by means of wireless sensor networks for both indoor and outdoor environments. To achieve higher localization accuracy, extra hardware equipments are utilized by most of the existing localization solutions, which increase the cost and considerably limit the location-based applications. The Internet of Things (IOT) integrates many technologies, such as Internet, Zigbee, Bluetooth, infrared, WiFi, GPRS, 3G, etc., which can enable different ways to obtain the location information of various objects. Location-based service is a primary service of the IOT, while localization accuracy is a key issue. In this paper, a higher accuracy localization scheme is proposed which can effectively satisfy diverse requirements for many indoor and outdoor location services. The proposed scheme composes of two phases: (1) the partition phase, in which the target region is split into small grids; (2) the localization refinement phase, in which a higher accuracy of localization can be obtained by applying an algorithm designed in the paper. A trial system is set up to verify correctness of the proposed scheme and furthermore to illustrate its feasibility and availability. The experimental results show that the proposed scheme can improve the localization accuracy.     

Online scheduling on batching machines to minimise the total weighted completion time of jobs with precedence constraints and identical processing times

This article studies online scheduling of equal length jobs with precedence constraints on m parallel batching machines. The jobs arrive over time. The objective is to minimise the total weighted completion time of jobs. Denote the size of each batch by b with b?=?∞ in the unbounded batching and b? m , where ρ _m is the positive solution of ρ ^m+1???ρ?=?1. The algorithm is also best possible when the jobs have identical weights. For the bounded batching version with identical weights of jobs, we provide an online algorithm with a competitive ratio of 2.     

关于全省粮食经济结构体系创新问题的思考

本文旨在从主销区加快粮食购销市场化改革进程,放开粮食收购,粮食价格由市场供求形成,粮食主产区继续坚持“三项政策、一项改革”的大形势出发,对如何在进一步深化粮食流通体制改革过程中实现我省粮食经济结构战略性调整发表一些粗浅的认识。     

量子绝热近似条件与量子几何势

阐述了传统量子绝热定理，给出了传统的量子绝热近似条件.基于传统的量子绝热近似条件存在不足，采用微扰论思想，通过 绝热变换不变，给出并讨论了新的绝热理论以及新的绝热近似条件.最后对新的绝热条件中所包含量子几何势的几何性进行了较为深入的分析和讨论.     

住宅电气设计探讨

根据住宅电气设计的实践,对住户用电量、配电系统、插座布置、电视、电话、安全防范、防雷接地等几方面问题作间接探讨。     

Bio-hydrogen production from cornstalk wastes by orthogonal design method

One-factor-at-a-time design and orthogonal design were used in the experimental design methods to optimize bio-hydrogen (bio-H₂) production from cornstalk wastes by anaerobic fermentation. Three series of experiments were designed to investigate the effects of substrate concentration, initial pH and orthogonal design on the bio-H₂ production by using the natural sludge as inoculant. Experimental results indicate that substrate concentration was the most significant condition for optimal hydrogen production. The optimum orthogonal design method was proposed to be at an enzymatic temperature of 50 °C, an enzymatic time of 72 h, an initial pH of 7.0 and a substrate concentration of 10 g/L. The proposed method facilitated the optimization of optimum design parameters, only with a few well-defined experimental sets. Under the proposed condition, the maximum cumulative H₂ yield was 141.29 ml g^?1-CS (cornstalk, or 164.48 ml g^?1-TS, total solid, TS = 0.859 W_{dried cornstalk}), with an average H₂ production rate of 12.31 ml g^?1-CS h^?1. The hydrogen content reached 57.85% and methane was not detected in the biogas.     

三网融合下PON网络维护管理方法探讨

目前三网融合在我国已经进入了实施启动阶段。本文介绍了在三网融合进程中电信运营商PON网络的状况,分析了电信运营商PON网络维护管理工作的现状和问题,提出了基于网络资源管理系统的PON网络维护管理模式。