Using bidirectional links to improve peer-to-peer lookup performance

INTRODUCTION Peer-to-peer computing has become a populardistributed computing paradigm. Efficient resourcelookup is essential for such systems. As we know, most of the deployed peer-to-peersystems are unstructured. Napster is based on a cen-tral directory and was in popular use during early daysSoon after, Gnutella and KaZaA were deployedwidely. However, all these popular unstructuredpeer-to-peer systems suffer from unscalability. Fortunately, there are new kinds of peer-to-peernetwor…     

Patterns in how pre-service elementary teachers formulate evidence-based claims about student cognition

Large-scale, robust implementation of teacher data-driven decision making (DDDM) is a challenging endeavor, impeded by numerous organizational, and teacher, factors. One well-documented barrier to teacher DDDM is underdevelopment of teacher data literacy. This study examines common errors made by pre-service elementary teachers in the formulation of evidence-based claims about student cognition (e.g. student strengths and weaknesses relative to content mastery) in a United States of America context. Teachers in the sample commonly made several errors in the articulation of evidence-based claims based on classroom assessments, including providing nonspecific, irrelevant evidence for claims, and misinterpreting statistical evidence. Specific implications for pre-service teacher education and future research are discussed.     

What Satisfies Students? Mining Student-Opinion Data with Regression and Decision Tree Analysis

To investigate how students' characteristics and experiences affect satisfaction, this study uses regression and decision tree analysis with the CHAID algorithm to analyze student-opinion data. A data mining approach identifies the specific aspects of students' university experience that most influence three measures of general satisfaction. The three measures have different predictors and cannot be used interchangeably. Academic experiences are influential. In particular, faculty preparedness, which has a well-known relationship to student achievement, emerges as a principal determinant of satisfaction. Social integration and pre-enrollment opinions are also important. Campus services and facilities have limited effects, and students' demographic characteristics are not significant predictors. Decision tree analysis reveals that social integration has more effect on the satisfaction of students who are less academically engaged.     

电流自适应调节器在双闭环直流调速系统的应用

在双闭环直流调速系统中,当电枢回路的电流断续时,由于系统参数的变化,使系统的调速性能变坏,严重时导致系统不稳定.在系统中使用电流自适应调节器可以使调节器的结构和参数自动随系统参数的变化而变化,来改善系统的性能.     

硬盘软故障的修复和保护

本文对硬盘硬盘软故障现象进行分析,找出解决方法.并提供了一种保护方法.     

决策支持系统控制程序的自动生成方式

分析了框架专家系统特点的基础上,提出了一种基于框架专家系统的决策支持系统控制程序的自动生成方式,从而提高了决策支持系统能够针对具体问题及时做出正确决策的能力,并使其自身具有动态重组能力来适应变化的决策环境.     

卡诺图在并联型ADC编码电路设计中的应用

根据组合逻辑电路的设计方法，突出用卡诺图化简逻辑表达式在并联比较型A／D转换器编码电路设计中的应用。     

施工企业投标决策的综合分析

工程投标是一项消耗人力、物力、财力和时间的工作，施工企业若不加选择地对多个工程进行投标，一旦不能中标，势必造成企业人、财、物的浪费。本探论了工程投标的多参数决策问题，在主成份分析的基础上，通过选择投标的评价指标和确定各指标的权重，建立投标决策模型与评价标准，以指导施工企业科学投标，并给出了应用实例。     

文化对决策主体的作用与影响

文化是影响主体活动的基本因素。传统文化铸就了传统观念，对主体活动产生了深重影响，科学文化使决策主体的决策程序，技术，方法及价值观产生飞跃，以全新的观念，科学决策，推动社会进步。     

刍议档案工作人员的档案意识

本文论述了档案与档案工作者在两个文明建设中及社会实践决策过程中作用,同时也阐述了档案部门必须挖掘内部潜力,拓宽档案信息内容,适应市场经济的需要,不断强化档案的管理,使之适应社会信息化的需要。