A Review of Contact Electrification at Diversified Interfaces and Related Applications on Triboelectric Nanogenerator

The triboelectric nanogenerator(TENG)can effectively collect energy based on contact electrification(CE)at diverse interfaces,including solid–solid,liquid–solid,liquid–liquid,gas–solid,and gas–liquid.This enables energy harvesting from sources such as water,wind,and sound.In this review,we provide an overview of the coexistence of electron and ion transfer in the CE process.We elucidate the diverse dominant mechanisms observed at different interfaces and emphasize the interconnectedness and complementary nature of interface studies.The review also offers a comprehensive summary of the factors influencing charge transfer and the advancements in interfacial modification techniques.Additionally,we highlight the wide range of applications stemming from the distinctive characteristics of charge transfer at various interfaces.Finally,this review elucidates the future opportunities and challenges that interface CE may encounter.We anticipate that this review can offer valuable insights for future research on interface CE and facilitate the continued development and industrialization of TENG.

分布式网络中连续时间周期的全局top-K频繁流测量

在分布式网络中,测量top-K频繁流对资源分配、安全监控等应用至关重要。现有的top-K频繁流测量工作存在不适用于测量分布式网络流量或只考虑单时间周期等局限。为此,提出了分布式网络中连续时间周期的全局top-K频繁流测量方案,在分布节点中布置了紧凑的概率数据结构来记录网络流信息,每个时间周期结束后分布节点向中心节点发送必要信息,中心节点汇聚得到从测量开始至当前时间周期的全局top-K频繁流。考虑到每条流可能出现在一个或多个测量节点,使用了不同的方法来减少传输开销。对于每条流只会出现在单一节点的情况,采用传输分段最小值的方法来获得阈值,实验结果表明这种方法减少了全量传输超过50%的传输开销。对于每条流会出现在多个节点的情况,提出了多阶段无误差处理方法和单阶段快速处理方法,分别应对不能容忍误差的场景和实际高速网络流量,相比每个时间周期都使用已有单周期方法,传输开销的实验表现降低了两个数量级。最后还提出了一种利用历史平均增值信息降低通信延迟的方法,实验结果表明该方法有效降低了限制信息的平均相对误差。

一次性条件下top-k高平均效用序列模式挖掘算法

针对传统序列模式挖掘(SPM)不考虑模式重复性且忽略各项的效用(单价或利润)与模式长度对用户兴趣度影响的问题,提出一次性条件下top-k高平均效用序列模式挖掘(TOUP)算法。TOUP算法主要包括两个核心步骤:平均效用计算和候选模式生成。首先,提出基于各项出现位置与项重复关系数组的CSP(Calculation Support of Pattern)算法计算模式支持度,从而实现模式平均效用的快速计算;其次,采用项集扩展和序列扩展生成候选模式,并提出了最大平均效用上界,基于该上界实现对候选模式的有效剪枝。在5个真实数据集和1个合成数据集上的实验结果表明,相较于TOUP-dfs和HAOP-ms算法,TOUP算法的候选模式数分别降低了38.5%~99.8%和0.9%~77.6%;运行时间分别降低了33.6%~97.1%和57.9%~97.2%。TOUP的算法性能更优,能更高效地挖掘用户感兴趣的模式。

Design of Diversified Intelligent Control System for Energy-saving Optimization of Solar Greenhouse in North China

Intelligent greenhouse can promote the development of modern agriculture, realize the high quality and high yield of crops, and also bring greater economic benefits. In accordance with the climate conditions in northwest China, a set of intelligent control system for diversified environment of solar greenhouse was designed. The system divides the annual greenhouse control into six stages according to the optimal energy saving. It uses modern detection technology to collect the greenhouse environmental temperature, environmental humidity, soil humidity, CO_(2) concentration and illumination parameters under different working modes. It uses programmable logic control technology to realize the data processing of various parameters and the action control of rolling film, wet curtain fan and other actuators. It uses KingView monitoring software to realize the monitoring and manual control of greenhouse environment parameters. The operation results indicate that the control system runs stably and basically meets the control requirements.

Diversified Teaching Method in Basic Piano Course Instruction for Higher Education Teachers

Diversified teaching plays an important role in the sustainable development of China’s basic piano course instruction for higher education teachers.A diversified curriculum system should be designed to promote the development of each student,and efforts should be made to cultivate high-quality talents who can adapt to the various needs of the society as well as to promote the reform and development of basic piano course instruction for higher education teachers.The aim of this study was to explore the teaching of basic piano course for higher education teachers based on the diversified teaching method.The teaching methods use for basic piano course were analyzed in this study,and two research methods were used to carry out the present study so as to effectively improve the operation of the diversified teaching method.Through a survey of the current situation of piano instruction in two higher education faculties,we can see that the teaching of basic piano course in higher education is still dominated by the traditional teaching method although the majority of students preferred the diversified teaching method.

PeakSketch:检测网络流中的top-k流的无偏和通用草图

通过对现有Sketch结构的研究,提出一种新的Sketch结构:PeakSketch,本文将其应用于三种任务:检测top-k频繁流,检测top-k重变化流,检测top-k持久流,从理论上证明了PeakSketch可以提供无偏估计,并且给出了算法的误差界。实验结果表明,PeakSketch的各项性能优秀,在检测top-k频繁流任务中,PeakSketch的吞吐量显著提升,特别是在分配内存小于200 kB以下时,吞吐量最高提升可以达到50%,准确率最高提升一倍,PeakSketch也展现突出的性能。

大图中多样化Top-k模式挖掘算法研究

频繁模式挖掘(Frequent Pattern Mining,FPM)是图数据挖掘领域的一项重要任务。该任务的目标是从图数据中找到出现频次大于给定阈值的所有模式。近年来,随着社交网络等大规模图数据的涌现,单一大图上的FPM问题受到广泛关注,并得到了较为充分的研究,取得了一系列研究成果。然而,已有技术大都存在着计算成本高、挖掘结果理解困难以及并行计算难等问题。针对上述问题,文中提出了一种从大规模图数据中挖掘多样化top-k模式的方法。首先设计了一个多样化函数,用于度量模式集合的多样性;随后设计了一种面向分布式图数据,具有提前终止特性的分布式挖掘算法DisTopk,以实现多样化top-k模式高效挖掘。在真实图数据和合成图数据上进行了大量实验,结果表明,与传统分布式挖掘算法相比,DisTopk算法能更高效地挖掘多样化top-k模式。

Top-k空间偏好查询方法研究

随着无线通信技术的发展和智能移动终端的广泛普及,基于位置的服务已经融入了人们生活的方方面面。其中,Top-k空间偏好查询在地理信息系统、城市建设规划、资源调度与分配、旅游规划等领域具有重要的意义。Top-k空间偏好查询是根据空间对象周围的特征对空间对象进行等级评价,并返回具有最高等级评价的k个空间对象。目前,对于Top-k空间偏好查询的研究主要集中在欧式空间和路网环境,本文对欧式空间和路网环境下的Top-k空间偏好查询方法进行分析和比较。

基于本地差分隐私的网络测量Top-k目的地址估计研究

针对网络测量中的Top-k目的地址问题,设计了基于布谷鸟过滤器的ε-本地差分隐私Top-k目的地址估计机制。在保护隐私的前提下,该机制能够提高对Top-k目的地址的估计效果。采用了多轮迭代方法,将布谷鸟过滤器和本地差分隐私模型结合,在服务器端和客户端进行了一轮交互。理论分析部分证明了所提出的机制符合本地差分隐私模型,并在数据集上进行了实验,对比了F1分数、NCR分数以及L1误差,验证了所提机制的有效性。

道路网多用户偏好Top-k天际线查询方法

已有的天际线(Skyline)查询主要聚焦于单用户场景,并基于单用户模型进行Skyline计算,而较少考虑道路网环境下多用户情况.为了弥补已有方法无法解决道路网络环境下多用户偏好和权重Top-k Skyline查询问题的不足,提出了一种基于道路网环境下多用户偏好Top-k Skyline(multi-user preference Top-k Skyline,MUP-TKS)查询方法.在道路网环境下考虑多用户的不同偏好和权重进行Skyline查询,可以快速得到符合查询用户群偏好和权重的结果集,提供用户群更好的决策支持.MUP-TKS首先通过所提的G_DBC算法,利用道路网中数据点与查询点之间的位置关系和新的索引结构Vor-R*-DHash剪枝、过滤数据点,从而得到距离较优集;再利用静态Skyline集不变的性质,预先计算、保存该集合;然后通过所提的新支配关系对距离较优集与静态Skyline集取并集后的集合S进行放松支配;最后利用所提TK_DC算法对经过放松支配后的候选结果集打分,依据数据点得分情况,排序输出Top-k个结果集返回用户群.理论研究与实验表明,所提方法具有较好的效率与可靠性.

卷积神经网络的top-k相似节点搜索方法

针对复杂网络环境下搜索与目标节点文本和结构均相似的top-k节点问题,本文提出了一种基于卷积神经网络的top-k相似节点搜索算法LRE-CNN.对于一个无向带权复杂网络,首先为网络中每个节点构造基于度和权重的最近邻网络模型,利用最近邻网络相对加权熵计算度和权重对节点结构的影响.然后,通过KL散度比较节点对的差异生成节点结构相似度,从而筛选出目标节点的候选相似节点.最后,利用卷积神经网络(CNN)抽取目标节点和候选相似节点的文本特征间的潜在关系,从而预测出与目标节点文本结构均相似的top-k节点.通过在不同规模的复杂网络上进行实验,并与现有主流相似节点搜索方法进行对比,实验结果表明所提方法具有较高的检索准确率,同时具有较高的执行效率,能够有效适用于大规模复杂网络环境下的相似节点top-k搜索.

Species-diversified plant cover enhances orchard ecosystem resistance to climatic stress and soil erosion in subtropical hillside

Naturally occurring plants in agroecosystem evidently play an important role in ecosystem stability. Field studies on the ecological effects of native plants conserved in orchard and their resistance to adverse climatic stress, and soil erosion were conducted from 1998 to 2001 in a newly developed Changshan-huyou (Citrus changshan-huyou Y.B. Chang) orchard. The experimental area covered 150 ha in typical red soil hilly region in southeastern China. The experimental design was a randomized complete block with six combinations of twelve plant species with four replications. All species used were native in the orchard. Plots were 15×8m^2 and separated by 2m buffer strips. Precipitation, soil erosion in rainstorm days and aboveground biomass of plant community when rainstorm days ended, soil temperature and moisture under various plant covers during seasonal megathermal drought period, antiscourability of soil with different root density under various simulated rainfalls were measured. Plant cover significantly decreased the daily highest and mean soil temperature and its daily variation in hot-drought season, but there was no significant difference of the alleviation among various plant covers. Plant covers significantly increased the soil moisture in seasonal megathermal drought period. Better moisture maintenance and soil erosion reduction was found when the plant species numbers in cover plant communities increased from one to eight. Higher root density in plant communities with higher species richness increased significantly the antiscourability of the soil. It was suggested that conserving plant communities with diversified native species could produce the best positive ecological effects on citrus orchard ecosystem stability.

通用可重组安全的多方求解Top-k协议设计

对于一个定点数多重集合S,第k小元素(又称Top-k元素) x∈S是指当集合中元素按照递增顺序排列时,刚好位于第k位置的元素.两方或多方安全求解它们输入的公共集合X的Top-k元素,是安全多方计算应用领域的经典案例.它能够使互不信任的多个数据持有方在不泄露自身数据的前提下,获取更大样本集合上的统计信息,从而实现隐私保护决策.本文提出了一种两方或多方分布式持有定点数数据的场景下,不依赖可信第三方,安全求解它们数据集合X中Top-k元素的协议,证明了其通用可重组(UC)安全性.协议使用了基于秘密分享的比较及加法安全多方计算协议作为构造模块,巧妙地从高到低按位依次确定并公布Top-k元素的p进制定点数表示.协议实现了O(logpM)的通信轮次复杂度,其中M为p进制数的最大取值, p为约定的定点数基数.实验证明,对于常见网络环境(包括局域网和广域网),当p=2^(i)(i=2,···, 8)时,协议的通信时间和总运行时间均显著优于其他现有的Top-k求解协议.

Diversified Teaching Methods in Nursing:Using Animal Experimentation to Promote Core Professional Competencies in Basic Nursing Training

Objective： The aim of this project was to train highly professional and specialized nursing students from medical colleges to adapt to bedside clinical care by exploring and discussing various methods of injection and IV infusion in animal experimentation to hone the core professional nursing competencies. Methods： Two classes from the 2012 senior graduating nursing class were randomly selected by a computer to conduct the diversified practical teaching methods based on animal experimentation. A hospital environment was simulated by requiring students to perform different types of injections and practical IV infusion techniques. A comprehensive evaluation of the core professional competencies, as well as other integrated competencies, was conducted to determine the effectiveness of the teaching methods. Results： Two-sampled, pairwise u-tests were performed between the scores of the experimental （nursing class 2） and control （nursing class 1） groups. These findings showed that the overall test scores were significantly higher in the experimental group compared to the control group and that the average P-values for the competencies in various categories were 〈0.01, which indicated statistically significant results. Conclusions： Based on the data from this project, diversified teaching methods for basic nursing training founded on animal experimentation can help nursing students perfect their core professional competencies and improve their overall professional standing. The introduction of animal experimentation requires further verification, and an increased acknowledgement of its benefits through the widespread dissemination of this information.

The Formulation of Water System Planning of Jingdezhen Under Diversified Needs

The water system is the basic condition for urban development, and a key resource and environmental carrier in the process of urban formation. It has an important restrictive effect on the survival of the city. Based on the diversified needs of urban water system development, this paper explores the preparation of the urban water system planning of Jingdezhen, strengthens the protection of water system and environmental quality, and explores urban cultural connotation, in order to build a unique urban water environment.

Research on the supervision system of social security fund ——based on the diversified supervision subject

Social security fund is the foundation of the social security to run, so to strengthen the supervision of social security fund, and promote the sustainable development of it is particularly important. However, the supervision of social security fund of China exists many difficulties at present. In this paper ,the author will be based on the angle of the diversity of regulation, and put forward some relevant suggestions to improve the system of supervision of social security fund.

云环境下一种强隐私保护的安全Top-k查询方案

在一个多用户应用场景下,为了防止云勾结一个数据拥有者或一个数据使用者对授权用户的查询隐私进行合谋攻击,构建了云计算环境下针对查询隐私的合谋威胁模型,并实现了一种高效的强隐私保护查询方案.方案采用动态的安全查询索引结构,该结构可以保证外包数据的安全性,且适用于数据文件频繁动态更新的多用户环境,极大地提高了系统的可伸缩性和可用性.为了满足用户的个性化查询需求,依据关键字权重对查询结果进行秘密相关性排序,实现了安全的top-k查询.

Development of Natural Gas in China--Concentrating Resources to Accomplish Major Undertakings, and Expediting Development through Diversified Ownerships

The development of China＇s natural gas industry can be described as the story of an ancient but rising industry. In general, the route for China＇s natural gas development is through concentrating resources to accomplish major undertakings, and expediting development through diversified ownerships.

Public Security Crisis Management Model Based on Diversified Cooperation

Everyone is surrounded by crisis just like the air we breathe at every moment;therefore, all countries, organizations and person are confronted with the risk challenges. Nowadays, the human society has evolved to a relatively advanced stage, and along with society progress, complicated social relationship and environment will result in more dangerous elements, thus bringing in more risks. This paper introduces the public security crisis management model based on diversified cooperation in detail from the concept of public security crisis and puts forward safeguard mechanism construction for enhancing the crisis management under diversified cooperation in a brief manner, thus improving the efficiency of crisis management under diversified cooperation.