"教育评估中介机构"概念质疑

本文从语词含义和造词宗旨入手,剖析了中介机构与评估机构、中间机构、缓冲组织的区别,以论证“教育评估中介机构”概念不当而应予废弃。     

机会网络中基于能量消耗的缓存管理策略

为了减少机会网络中节点的能量消耗,均衡各节点之间能量使用情况,延长网络寿命,提出基于能耗的缓存管理策略。在节点缓存空间有限的情况下,所提出的算法根据周围邻居节点能量的使用情况,动态调整节点用于缓存转发消息空间的大小,从而减少节点在存储-转发过程中的能量消耗。同时,为了避免传统休眠机制的能耗路由算法中由于目的节点休眠而导致消息投递失败的情况,引入了新的Inactive节点状态。实验仿真表明,与定时休眠机制的能耗算法比较,采用基于能量消耗的缓存管理策略能够使得机会网络中所有节点的整体能耗降低50%左右,并且节点之间能耗的标准差降低80%以上。     

Reducing cache and TLB power by exploiting memory region and privilege level semantics

The L1 cache in today’s high-performance processors accesses all ways of a selected set in parallel. This constitutes a major source of energy inefficiency: at most one of the N fetched blocks can be useful in an N-way set-associative cache. The other N-1 cachelines will all be tag mismatches and subsequently discarded.We propose to eliminate unnecessary associative fetches by exploiting certain software semantics in cache design, thus reducing dynamic power consumption. Specifically, we use memory region information to eliminate unnecessary fetches in the data cache, and ring level information to optimize fetches in the instruction cache. We present a design that is performance-neutral, transparent to applications, and incurs a space overhead of mere 0.41% of the L1 cache.We show significantly reduced cache lookups with benchmarks including SPEC CPU, SPECjbb, SPECjAppServer, PARSEC, and Apache. For example, for SPEC CPU 2006, the proposed mechanism helps to reduce cache block fetches from the data and instruction caches by an average of 29% and 53% respectively, resulting in power savings of 17% and 35% in the caches, compared to the aggressively clock-gated baselines.     

ORACLE数据库SQL优化原则

Oracle数据库是当前应用最广泛的大型数据库之一,其系统结构复杂,性能受多方面因素影响,其中SQL语句的执行效率是影响其性能的关键因素。以一个省级通信运营商的ORACLE ERP系统为例,从ORACLE数据库的SQL共享原理和SQL执行过程入手,指出合理配置数据库参数,提高SQL语句共享、提高数据缓存命中率是SQL语句性能提高的前提;并在此基础提出了SQL语句优化的四个原则。     

体检系统中尿液检查接口的设计与实现

在尿常规检查中,将检查结果自动上传到体检数据库,这不仅可以提高工作效率、服务质量还可以提升医院体检工作的信息化管理水平。在接口设计的时候,通过对传统串口数据接收方法进行分析,结合数据缓存思想,提出一种基于缓冲区的实时串口数据接收方法,同时采用多线程技术实现FA-200型尿液分析仪数据的批量接收。本设计在我校医院一年多的体检中得到了有效的验证,实现了预期的目标。     

Performance enhancement of TCP in high-speed networks

GridFTP is a secure and reliable high-performance parallel data transfer protocol used for transferring massive amounts of widely distributed data. Currently it allows users to configure the number of parallel streams and socket buffer size. However, its tuning procedure for optimal combination is a time consuming task. The socket handlers and buffers are important system resources and must therefore be carefully managed. In this paper, we propose a scheme to achieve high throughput even with a smaller buffer size, and also derive a regression equation to predict the optimal combination of resources for a connection. To improve the performance, the TCP based on our scheme obtains higher throughput and spends less memory for the same throughput than the original TCP scheme. In addition, the regression equation is verified by comparing measured and predicted values, and we apply the equation to an actual experiment on the KOrea advanced REsearch Network (KOREN). The result demonstrates that the equation provides excellent predictions with only an 8% error boundary.     

Determination of optimal size of the de-jitter buffer of a receiving router

The influence of the size of the de-jitter buffer of a receiving router and of the network load on the transmission quality of voice traffic is investigated by means of simulation modeling. The optimal size of the de-jitter buffer that supports an acceptable level of loss of voice packets and a propagation time of the voice signal that corresponds to accepted standards is determined.     

Drug self-assembly: A phenomenon at the nanometer scale with major impact in the structure–biological properties relationship and the treatment of disease

Under water-rich conditions, small amphiphilic and hydrophobic drug molecules self-assemble into supramolecular nanostructures. Thus, substantial modifications in their interaction with cellular structures and the ability to reach intracellular targets could happen. Additionally, drug aggregates could be more toxic than the non-aggregated counterparts, or vice versa. Moreover, since self-aggregation reduces the number of effective “monomeric” molecules that interact with the target, the drug potency could be underestimated. In other cases, the activity could be ascribed to the non-aggregated molecule while it stems from its aggregates. Thus, drug self-assembly could mislead from drug throughput screening assays to advanced preclinical and clinical trials. Finally, aggregates could serve as crystallization nuclei. The impact that this phenomenon has on the biological performance of active compounds, the inconsistent and often controversial nature of the published data and the need for recommendations/guidelines as preamble of more harmonized research protocols to characterize drug self-aggregation were main motivations for this review. First, the key molecular and environmental parameters governing drug self-aggregation, the main drug families for which this phenomenon and the methods used for its characterization are described. Then, promising nanotechnology platforms investigated to prevent/control it towards a more efficient drug development process are briefly discussed.     

强酸强碱溶液“缓冲容量”的讨论

本文从缓冲微分方程式说明强酸、强碱溶液具有缓冲能力,并且比同总浓度的由共轭酸碱对组成的缓冲溶液的缓冲容量大。     

用于缓冲区生成的随机算法

缓冲区分析是GIS中重要的空间分析方法之一。针对现有方法处理大数据量矢量地图时的低效率问题,提出一种易于并行处理和编程实现的缓冲区生成的随机算法,并设计适用于多种形式的应用模式,以适应缓冲区分析普适性应用。采用舍伍德随机算法优化计算效率,利用可伸缩矢量图形遮罩对象解决可视化问题。测试结果证明,该算法可以提高大数据集的处理效率。