分布式系统上异构拥有源服务质量的优化研究

提出的正交同步解调法(即GQSD算法)是一种可用来减少种群代的最大重复次数的新技术手段。GQSD算法有助于在现有(非旧式的)优化算法上使处理源调度达到最优化。GQSD是一种通过界定新参数和度量数据来降低任务延时以及响应用时的新型算法。GQSD算法还达到服务器的服务水平。模拟实验表明采用GQSD算法后,分布式系统的总任务进程的完成时间得到缩短,性能有所提高,从而使得不同层次分布式处理器的服务质量得到提高,处理延时也大大降低。     

“匹配式”教学方法改革的实践效应

经过多年高职高专教学实践,本人探索出“学导式”与“加分法”相匹配的全新教学方式。本对此进行了比较详细的阐述。     

Mathematical Analysis of Energy Efficiency in IEEE 802.11 DCF

The standardized IEEE ,802. II distributed coordination function （ DCF） provides a contention-based distributed channel access mechanism for mobile stations to share the wireless medium. However, when stations are mobile or portable units, power consumption becomes a primary issue since terminals are usually battery driven. This paper proposes an analytical model that calculates the energy efficiency of both the basic and the RTS/CTS access mechanisms of the IEEE 802. II protocol. The model is validated with simulation results using NS-2 simulation package. The effects of the network size, the average packet length, the initial contention window and maximum backoff stages on the energy efficiency of both access mechanisms are also investigated. Results show that the basic scheme has low energy efficiency at large packet length and large network size, and depends strongly on the number of stations and the backoff procedure parameters. Conversely, the RTS/CTS mechanism provides higher energy efficiency when the network size is large, and is more robust to variations in the backoff procedure parameters.     

B/S模式程序中的分布式计算应用一例

B／S模式的应用程序主要是集中式计算和处理，本简要的以实例无纸化考试系统设计，说明了在B／S模式中采用分布式计算处理的一种思路。     

一种基于聚类与关联规则算法的DDoS攻击检测模型

分布式拒绝服务（Distribute Denial of Service）攻击是当前主要的网络安全威胁之一．本文分析了DDoS攻击的本质特征,提出了一种基于数据挖掘算法的DDoS攻击检测模型．该模型使用聚类算法与关联规则对网络流量与网络数据包连接状态分别建立特征模型,并确定DDoS攻击的检测阈值．实验表明,该检测模型能够实时有效的检测DDoS攻击．     

我国区域人才结构优化与产业结构升级的协调适配度评价研究

基于协同学理论,构建了区域人才结构优化与区域产业结构升级耦合的复合系统,将区域人才结构优化的4个时序环节与区域产业结构升级两个导向维度耦合对接提取复合系统序参量,形成协调适配度评价指标体系,采用功效函数法进行测算。以全国30个省市区域(除西藏外)为样本进行了协调适配度的实际测评,结果表明,各省市的协调适配度共可分为四种类型,且协调适配等级并不高。针对不同协调适配类型,对各省市提出未来改进和发展对策。     

Is academic tracking related to gains in learning competence? Using propensity score matching and differential item change functioning analysis for better understanding of tracking implications

This study analyzes gains in cognitive components of learning competence with respect to cohorts based on ability tracking in a Czech longitudinal study. Propensity score matching is used to form parallelized samples of academic and non-academic track students and to eliminate the effect of selective school intake. We applied regression models on the total scores to test for the overall track effect. Furthermore, we analyze scores and gains on the subscores and check for differential item functioning in Grade 6 and in change to Grade 9. While after 3 years, no significant difference between the two tracks was apparent in the total learning competence score, we did, however, find significant differences in some subscores and in the functioning of some items. We argue that item-level analysis is important for deeper understanding of the tracking implications and may provide the basis for more precise evidence-based decisions regarding the tracking policy.     

The Development and Design of a Framework to Match Mentees and Mentors Through a Systematic Review andThematic Analysis of Mentoring Programs Between 2000 and 2015

ABSTRACT

The need for longitudinal and holistic support of medical students throughout their training has led to the development of formal mentoring programs. Whilst success of formal mentoring programs has been attributed to (a) pairing mentees with trained and experienced mentors (matching), (b) the quality of mentoring interactions and (c) the presence of a nurturing environment, little attention has been attributed to establishing an effective matching process in medical school. We sought, in this review, to redress this gap within the context of matching medical students for mentoring. Modified PRISMA guidelines were followed to guide the review process. PubMed, ERIC, Cochrane Database, OVID and ScienceDirect databases were searched for articles on matching in medical schools and in allied health specialities published between 2000 and 2015.     

Distributed leadership for personalized learning

Abstract

Personalized learning refers to a collection of practices designed to place student interests and needs at the heart of schooling. Schools that implement personalized learning need leaders that support educators and students in redesigning the core practices of teaching and learning in K-12 schools. To answer the question of how leaders support this redesign, we use distributed leadership theory to focus on the macrotasks and microtasks that leaders enact to create the conditions for personalized learning practices. Drawing on a five-year, qualitative study of 11 personalized learning programs in the Midwest, we identify three macrotasks supporting personalized learning: reorganizing learning environments to support student voice and choice, assembling idiosyncratic technology ecosystems to distribute teaching and learning tasks, and redesigning instructional time to prioritize student’s interests, agency, and learning relationships. After we describe a number of microtasks associated with each macrotask, we discuss how a consideration of these kinds of leadership tasks can open the contemporary discussion of personalized learning from a narrow focus on learning technologies to an expansive vision of student-centered school reform.     

高校教师学术创业对科研产出的影响——基于倾向值匹配的反事实估计

高校教师学术创业对科研产出的影响一直是国内外争论的焦点。通过收集我国四所“双一流”大学教师学术创业的数据,运用倾向值匹配法探究高校教师学术创业与科研产出之间的因果关系。研究得出如下结论：高校教师参与学术创业后,科研产出数量不会发生变化,但科研产出质量会有所下降;不同学科教师学术创业对科研产出的影响效应存在异质性,工科类教师学术创业对科研产出数量和质量均无显著影响,而理科类教师学术创业对科研产出质量存在显著的负向影响。基于此,为了减少冲突,实现“研创”共生,建议建立“支撑保障”与“边界限制”并行的学术创业管理体制,并根据不同学科的特点进行分类管理。