提高学生知识存储率的探索

物理教学活动的最终目标是学生在知识、能力以及思想意识品质等方面得到发展。因此,采用适当的手段,强化物理知识的记忆,提高知识的储存率,是提高中学物理教学质量的一个重要课题。

星载存储器吞吐率瓶颈与高速并行缓存机制

为解决目前星载存储器无法有效支持多路高速数据并行存储的问题,针对载荷数据高速输入需求,对基于NAND Flash的固态存储器的吞吐率瓶颈进行分析,根据固态存储器的固有写操作特性对有效吞吐率的影响,提出了四级流水线操作和总线并行扩展方案;针对多通道数据并行存储、流水线加载连续性等需求,对使用现场可编程门阵列FPGA(Field-Programmable Gate Array)内部双端口随机存取存储器RAM(Random access memory)、外置静态随机存取存储器SRAM(Static Random Acess Memory)等已有缓存方案的不足进行分析,完成了基于同步动态随机存储器SDRAM(Synchronous Dynamic Random Access Memory)的方案可行性分析与新型存储单元架构设计,最终提出了基于SDRAM的高速多通道缓存与存储协同调度方案.模型仿真与原型功能验证结果表明,方案在极限工况下可将4路高速文件数据连续并行接收缓存至SDRAM中,并可根据各分区缓存状态将文件数据按优先级自主动态写入Flash中,期间缓存无溢出,并最终进入常规动态平衡调度状态,实现了对多路高速载荷数据的并行接收缓存和自主调度存储,且存储器的数据吞吐率可达1.2Gbps,能够满足未来星载存储器对多路高速载荷数据存储的需求.

白细胞悬浮红细胞与悬浮红细胞储存期内溶血率的比较

目的探讨白细胞悬浮红细胞与悬浮红细胞储存期内溶血率的比较。方法选取我中心200m L的血浆61袋;61袋血液均抽取100 m L设为甲组,其余设为乙组。其中甲组不过滤白细胞,制成悬浮红细胞血浆;乙组过滤白细胞,制成去白细胞悬浮红细胞血浆。两组血浆均在冷藏柜中进行储存1个月。对比两组血浆中储存期内溶血率和游离血红蛋白浓度。结果乙组的游离血红细胞的浓度和溶血率显著高于甲组,具有统计学差异(P<0.05)。结论滤去白细胞的过程可能对红细胞造成损伤,但尚处于成分血液达标范围之内。

基于相对心率建立体力劳动强度评价模型

为掌握劳动者合理的劳动强度,本文以西宁某建筑工地的16名建筑工人作为研究对象,利用腕带式心率测量仪器测量建筑工人工作时的心率情况,并计算出相对心率、氧耗量和心率存储百分比,并建立线性回归模型,通过案例检验模型的正确性(模型的误差为10%左右)。结果表明:(1)较重劳动强度等级内相对心率(x)≥2.17,持续30 min会造成身体危害。(2)重度劳动强度等级内相对心率(x)≥1.78,持续60 min会造成身体危害。(3)中度劳动强度等级内相对心率(x)≥1.62,持续8 h会造成身体危害。综上所述,基于相对心率建立的评价指标模型,能够比较准确地计算出劳动者的劳动强度。

不同倾角单裂隙对非均质岩石失稳演化研究

岩体中的裂隙对岩石的力学行为、能量演化和失稳破坏有显著影响。为阐明不同倾角单裂隙对岩石能量演化和失稳破坏机理,基于颗粒流PFC2D方法,建立了不同倾角单裂隙砂质泥岩数值模型,模拟了不同倾角单裂隙下砂质泥岩的单轴压缩试验。研究表明,随着单裂隙倾角变大,砂质泥岩的强度与弹性模量先降低后增大,预制裂纹会影响断裂面的裂纹起始位置,并加速断裂面的形成;声发射事件在岩样破坏前存在小范围沉寂期,该特征可作为岩石破坏的前兆判据;随着裂隙倾角的增大,总能量持续增大,弹性能和耗散能呈现先增加后减小的趋势,倾角30°时,岩石试样冲击倾向性最弱,有利于降低冲击地压危险,倾角为90°时,岩石试样冲击倾向性相对最强,不利于冲击地压的防治。

基于选择性加载策略的电能质量数据处理

根据电能质量系统中监测数据海量化的趋势,提出了一种基于部分存储和选择性加载的数据处理算法,彻底解决了现有数据处理算法中重复排序和多余处理的问题。在计算日指标时,根据存储率存储部分日排序数据;在计算周(月、季、年)指标时,利用多路归并算法将存储的部分日排序数据合并,计算出临时95概率大值(CP95);根据临时CP95确定需要重载的日数据,对部分存储的日数据和重载数据重新排序以计算稳态指标。部分存储的日排序数据可以重复利用,有效解决了传统处理方案中的重复排序问题;排序过程中只需读取部分日排序数据和少量重载数据,有效解决了传统处理方案中冗余处理问题。与传统的数据处理方法做测试对比,结果表明:日采样数据较小时,性能提升3倍以上;日采样数据超过2880时,性能提升15倍以上。数据量越大,性能提升越明显。所提方案已在山西、河北等监测系统中成功应用,实践证明所提方案正确、有效。

基于FPGA的DDR SDRAM控制器设计

针对目前应用最为广泛的DDR SDRAM存储器,采用VHDL语言实现了基于ALTERA公司FPGA架构的、基于工业标准的通用DDR SDRAM控制器设计。重点介绍了读数据接口和写数据接口设计。在EP1C6Q240C8芯片上实现时的性能达到了133MHz的主频频率。

一种DDR SDRAM控制器设计

在分析DDRSDRAM基本操作原理的基础上,提出了一个基于FPGA的DDRSDRAM控制器的设计,实现了DDRSDRAM读写时序控制,并给出实现结果。

“信息化+多学科协作”管理模式在脐带血认知和储存中的应用

脐带血是胎儿娩出后残留在脐带和胎盘中的血液,其中含有丰富的造血干细胞。由于脐带血具备采集方便、被采集者无伤害、移植后排斥率低且程度较轻等优势,逐渐被医学界重视。近年来,脐带血造血干细胞的基础研究与临床应用有较多报道,成为新世纪干细胞研究领域中的热点问题[1]。有研究报道[2],孕妇接受有血缘关系供者的脐带血治疗白血病,其成活率比异基因移植孕妇的成活率高34%。因此,提高脐带血的认知度和储存率具有重要意义。

多进多出的高速视频缓存器设计

以DDR SDRAM为基础,设计了在IPQAM调制器中使用的多进多出结构视频缓存器。对操作指令集进行了最简优化,并给出了带宽设计模型,最后提出了针对资源消耗和时序约束进行改进的设计结构。实际测试表明该系统达到了预期设计目标。

房改与住房信贷业务知识

为更好地开展停住房公积金业务,推动我市住房制度改革进程,特将住房公积金缴交及住房信贷业务具体操作中的一些问题简做答复,业务中涉及的一些政策性问题由市改办负责解释。 一、单位怎样办理首次缴交住房公积金手续?单位在确定缴交住房公积金的职工范围后,按照职工工资总额的10％比例缴交,单位和职工的住房公积金存储率分别为5％。然后到有关承办房改金融业务的银行,购买有关房改凭证,填写“公积金汇缴清册”和“

IMPROVEMENT OF SANDY SOIL WITH WATER-CONSERVING MEMBRANE AND ITS EFFECT ON CROP GROWTH

Water-conserving membrane is a new material of improving sandy soil. It is based on the rule that a compound with organic and inorganic components can produce colloid after its integrating with Ca2+ in soil. The water-conserving membrane will obstruct capillary and increase viscidity of sandy soil, so as to decrease leakage and evaporation in sandy soil. The water-conserving membrane contains polyacrylic acid (PAA) and bentonite. When PAA concentration and pH of solution are different, water-conserving membrane can be made in different depth of soil. This experiment shows that the solution with 0.2% PAA does not harm and poison the crops, on the contrary, promotes crop germination. The solution with 0.2% or 0.4% PAA can accelerate corn growth. Accordingly, different crops need the application of the different PAA concentrations in the cultivation. Therefore, on the basis of different vadose coefficient in sandy soil, the solution with different PAA concentration can improve sandy soil and increase its water-conserving competence very well. The solution can be used to improve sandy soil and control desert enlargement in arid, semi-arid and semi-humid areas.

Effect of non-vacuum storage condition on minimum explosible concentration of aluminum dust

Non-vacuum storage condition has a great impact on the explosion characteristics of aluminum powders. In this paper, vacuum-packed flake and globular aluminum powders stored in a dryer after opening the vacuum package are selected as the experimental samples, and a 20 L spherical explosion device is chosen to test the minimum explosible concentration (MEC) values of aluminum dusts under different storage time. The results show that the MEC values of two types of unoxidized aluminum powders are 30 g/m^3. The MEC values of flake and globular aluminum powders firstly go up with the increase of storage time in the dryer and then reach the maximum values of 50 g/m^3 and 60 g/m^3 at respective storage time until finally they stabilize gradually. The main reason is that the oxidation rate is faster owing to the bigger specific surface area of globular aluminum powders. Hence, the storage time has more significant effect on the MEC of globular aluminum powder than that of flake aluminum powder. After a period of time, the outer surface is oxidized to generate a layer of film, which prevents the further oxidation of aluminum powder, resulting in the temporary stability of MEC.

谈谈数字示波器的选用

廿世纪八十年代以来,数字示波器因性能的优越逐渐取代了传统的模拟示波器。示波器的基本任务是为使用者捕捉、观察和分析信号,以及提供排除故障的工具。在选用时使用者应考虑:带宽、采样速率、触发性能、采集存储深度等技术指标。

MEMORY-EFFICIENT PATH METRIC UPDATE METHOD IN MAP DECODER IMPLEMENTATION

A novel memory efficient path metric update is proposed for Maximum A Posteriori(MAP) decoder of turbo codes to reduce the memory requirement of state metric information calcu-lation. For MAP decoder,the same memory can be shared by the forward and backward metrics with this metric update scheme. The forward and backward metrics update can be performed at the same time. And all of the extrinsic information can be calculated at the end of metric update. Therefore,the latency and area in the implementation will be reduced with the proposed metric update method.

Investigation of floor heating with thermal storage

Based on experimental data, the energy storage performances of floor radiant heating system were investigated. The decrease of indoor air temperature after the stopping of floor heating was compared with that of fan-coil heating system. The increase of indoor air temperature after the stopping of floor cooling system was analyzed. The results show that the floor heating system has good thermal storage performance, which can be used to a night-running model to obtain the energy-saving benefits efficient and economic running cost, and still can be used for “shifting peak load to off-peak” macroscopically.

Determinations of Air Tightness of Covered Slurry Storage Tanks Using Tracer Gas Technique

The objective of this investigation was to study whether it is possible to determine the air tightness of covered slurry storage tanks using tracer gas technique by injection of sulphur hexafluoride （SF6） and measurements of the decay in gas concentrations with an infrared spectrophotometer in the air space above the slurry. By measuring the decay in concentration of injected tracer gas at different occasions, the air exchange rate was determined. Three different types of coverings were studied namely; wooden roof, plastic tent and concrete roof.

Impacts of NBTI/PBTI on power gated SRAM

A signal probability and activity probability (SPAP) model was proposed firstly, to estimate the impacts of the negative bias temperature instability (NBTI) and positive bias temperature instability (PBTI) on power gated static random access memory (SRAM). The experiment results show that PBTI has significant influence on the read and write operations of SRAM with power gating, and it deteriorates the NBTI effects and results in a up to 39.38% static noise margin reduction and a 35.7% write margin degradation together with NBTI after 106 s working time. Then, a circuit level simulation was used to verify the assumption of the SPAP model, and finally the statistic data of CPU2000 benchmarks show that the proposed model has a reduction of 3.85% for estimation of the SNM degradation after 106 s working time compared with previous work.

Using probabilistic cache scheme to construct the small world network

Recently some P2P systems have constructed the small world network using the small world model so as to improve the routing performance.In this paper,we propose a novel probabilistic cache scheme to construct the small world network based on the small world model and use it to improve CAN,that is,PCCAN(Probabilistic Cache-based CAN).PCCAN caches the long contact.It uses the worm routing replacing mechanism and probabilistic replacing strategy on the cache.The probabilistic cache scheme proves to be an efficient approach to model the small world phenomenon.Experiments in both the static and the dynamic network show that PCCAN can converge to the steady state with the cache scheme,and the routing performance is significantly improved with additional low overheads in the network compared with CAN.

Return on Investment after Implementation of a Centralized Automated Storage System in a Hospital Pharmacy

An ADS （automated dispensing system） was implemented in our hospital pharmacy in 2008 to optimize and secure the medication process. The main objective of this study was to compare the projected and the real ROI （return on investment）, after seven years of use. ROI was calculated annually （from 2008 to 2015）, by deducting the cost of investment （ADS buying and implementation, maintenance, repairs and ADS upgrade） from the cost saving （drugs stock reduction and decrease of pharmacy staff dedicated to global dispensing）. In 2015, total costs saving （＋$1,141,987） were divided between decreasing drug stock value and reduction of pharmacy staff. Total costs of investment （-$978,656） were acquisition, maintenance, repairs and an unplanned upgrade costs. Finally, the real ROI was ＋$163,331 after seven years of use. In 2008, projected ROI was ＋$410,786. The real payback period has been increased by approximately two years （six years of use, instead of four years as expected）. Despite their cost, ADSs are a worthwhile investment, leading to a ROI within a few years. These economic considerations should be put into perspective with optimization of drugs stock management, greater efficiency of the global dispensing process, securitization of medication process and redeployment of pharmacy staff.