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Search Results: 1 - 10 of 11341 matches for " 伍芷蕾 ? "
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澳门特别行政区人口教育不均等研究
柯丽香,陈健新,
期刊检索-中国人口科学 , 2013,
Abstract: 文章运用教育基尼系数拆解模型分析了澳门1991-2011年人口普查数据中性别和年龄的教育不均等现象。结果发现,澳门教育不均等程度近20年有所改善,但不同年龄组间的教育不均等则有所加剧。鉴于澳门学历教育的急速发展导致的年龄层上的不均,作者建议未来中国的人口教育政策应该同时考虑到青壮年人口的正规教育和中老年人口的持续教育的均衡发展。
国际饭店行业等级评定制度:现状、趋势与启示
,杨宏浩
热带地理 , 2013,
Abstract: ?饭店行业等级评定制度随着旅游业发展而逐步建立并得到完善,其中机构设置、参与性质、实施范围及法律归属性一直是其基本内容。国际饭店等级评定制度范围广泛,形式多样,评定标准具有相似性和差异性,制度安排基本合理。但价值取向的局限性导致评定机构性质由官方机构向非官方机构或者官方和非官方联合机构演变;饭店业态的多样性、评定范围的局限性导致评定形式由定级向评级与评质相分离演变;新元素的纳入导致评定内容逐渐由产品导向型向顾客导向型转化;等级评定与品牌运用逐步发挥协同作用。国际上也出现建立世界统一的饭店等级评定标准等具有争议性的发展方向。未来我国饭店等级评定制度的创新和变革可从评定主体结构转化、评定制度规范化运行和评定内容与国际接轨等方面考量。
蓖麻油聚氨酯防水涂料的制备与性能研究
陈为,杨隽,,
涂料工业 , 2009,
Abstract: ?采用可再生的蓖麻油先分别与三羟甲基丙烷(tmp)、甘油反应,再与tdi反应,生成端基为—nco的蓖麻油基聚氨酯预聚体。对其—nco含量进行测试,并采用ft-ir对材料进行定性分析。并对固化后的涂膜附着力、力学性能、耐磨性和耐水性能进行了测试。结果表明:采用甘油醇解蓖麻油合成的聚氨酯性能较好,其最佳反应时间为3~4h,反应后—nco含量为4.90%~5.32%,体系在-10~40℃能固化成膜,且成膜物有较好的防水性能和力学性能。
免疫磁珠分选和mlpa技术联合检测多发性骨髓瘤分子遗传学异常系统的建立
雷鸣,马莉,邝丽萍,庞妍,九龙,,李力
南方医科大学学报 , 2012,
Abstract: 摘要:目的探讨联合免疫磁珠分选和多重探针连接依赖性扩增(mlpa)技术检测多发性骨髓瘤(mm)分子遗传学异常的可靠性。方法收集29例初诊mm患者的骨髓细胞,用cd138磁珠进行分选,设计mlpa探针检测分选前后标本tp53和rb1的表达情况,并与fish检测结果进行对照。结果mlpa检测成功率100%,与fish结果吻合度达99.1%,分选后mlpa和fish阳性率均有显著性提高。结论mlpa适合临床mm分子遗传学异常检测,标本应在检测前进行磁珠分选。
HPLC分析油菜籽油中维生素E的组成与含量
吕培军,,晓明
植物遗传资源学报 , 2011,
Abstract: 本文利用HPLC法分析了50份遗传背景丰富的白菜型油菜、甘蓝型油菜、芥菜型油菜和芸芥种子油中维生素E的组成与含量,研究结果显示,油菜种子油中主要含α-生育酚和?-生育酚,且α-生育酚、?-生育酚和维生素E总量均存在明显的基因型差异,甘蓝型油菜种子油中维生素E含量总体水平最高,平均总量较高,为123.11mg/100g油,维生素E含量最高的Omega,总量为144.73mg/100g油,α/?-生育酚比值最高可达0.77。α-生育酚、?-生育酚和维生素E总量与类胡萝卜素含量均呈现显著以上负相关,种子油中α-生育酚与含油量呈现显著正相关,α-生育酚、?-生育酚和维生素E总量与生育期均呈现显著或极显著正相关,α-生育酚和维生素E总量与株高均呈现显著正相关,维生素E总量与千粒重呈显著正相关,而α-生育酚、?-生育酚和维生素E总量与全株角果数和每角粒数相关不显著。
gps短基线整周模糊度的直接解法
,花向红,蔡华,
武汉大学学报(信息科学版) , 2009,
Abstract: ?提出了在位移值较大的情况下(0.7m),通过多种载波相位组合,解算短基线gps整周模糊度的方法。导出了在解算过程中保证l1和l2载波的整周模糊度n1和n2为整数的条件,从而将dc(directcalcu-lation)算法[1]不仅推广到大变形的情况,而且推广到短基线gps整周模糊度的解算,解决了快速准确解算短基线gps整周模糊度的问题。
实时修复双频原始载波相位观测值周跳的虚拟值探测法
,李海军,,王海军
武汉大学学报(信息科学版) , 2012,
Abstract: ?利用各频率观测值间物理上的相关性,采用数学变换得到一个含有双频原始载波观测信息的虚拟观测值,与双频数据按长波长特性进行多频组合来放大周跳。对探测出的周跳候选值利用melbourne-wubbena组合及多项式拟合作为两个判别条件来进行甄选,达到了实时修复双频原始载波相位观测值周跳的目的。
蜗壳垫层材料压缩-回弹响应行为的试验研究及数值模拟
张启灵,,胡超,鹤皋
- , 2018, DOI: 10.15961/j.jsuese.201700861
Abstract: 中文摘要: 垫层在水电站钢蜗壳-混凝土组合结构中起传递内水压力的作用,但在当前的设计实践中,垫层通常被简化为线弹性材料。本文选取聚氨酯软木与聚乙烯闭孔泡沫等2种最常用的蜗壳垫层材料,首先采用土工轴承式单杠杆固结仪对2种材料分别进行循环加-卸压试验,材料试样由环刀切割成型,受压过程在环刀内完成,最大压力荷载定为1.0 MPa,加压与卸压过程均分10级完成,级差0.1 MPa。而后根据试验中的垫层材料试样尺寸,建立试样的平面轴对称有限元模型,在ABAQUS平台上采用HYPERFOAM和MULLINS EFFECT两者共同模拟单次加-卸压循环中2种材料的非线性响应过程,2种模型中必要的材料参数通过UNIAXIAL TEST DATA选项结合材料的压缩应力-应变试验数据确定。研究结果表明:2种材料均具有显著的非线性、不可逆的压缩特性,在循环加-卸压作用下均存在显著的残余应变;数值模拟对2种材料在单次加-卸压循环中的应力-应变响应过程的预测效果良好。认为在蜗壳结构的设计中不应忽略垫层材料的非线性力学特性,前述基于ABAQUS平台的数值模拟技术能够简便地实现垫层材料的非线性力学描述。建议垫层材料在出厂前,宜提前经历足够次数和时长的“预压”过程,最大程度上降低垫层材料残余变形对蜗壳结构受力的潜在不利影响,垫层材料的力学设计参数须基于已经历过“预压”过程的试样压缩-回弹数据确定。
Abstract:Membranes play load-transferring roles between steel spiral cases and surrounding concrete in hydroelectric power plants. However, membranes are routinely recognized as linear-elastic materials in current engineering practices. The two most commonly-used membrane materials, i.e. the PU cork and PE foam, are chosen as the current study subjects. Cyclic compression-resilience tests were performed for the two materials with a lever-type consolidometer. The specimens were cut out with cutting rings and the cutting rings provide lateral confinement for the specimens in compression. The maximum pressure is 1.0 MPa with a loading/unloading interval of 0.1 MPa. Each loading/unloading cycle thus consists of 20 gradations. Then the HYPERFOAM model in conjunction with the MULLINS EFFECT option was employed to model the non-linear responses of the two materials in a single loading-unloading cycle based on the ABAQUS code. The specimen was modeled in line with its dimensions with CAX4 axisymmetric solid elements. The UNIAXIAL TEST DATA option was used to obtain the parameters for the HYPERFOAM model directly from the experimental stress-strain data. The strong evidence of the nonlinearity and irreversibility of the compressive behavior of both materials is found. The significant permanent set upon removal of the applied load was observed for both materials. The numerical simulation results fit well with the non-linear responses of the two materials in a single loading-unloading cycle. This study highlights the need to consider the non-linear compressive behavior of membrane materials in the structural design of spiral case structures. The presented simulation procedure based upon the ABAQUS code is practicable for the numerical description of the non-linear compressive behavior of membrane materials. To avoid as far as possible the potential adverse effects of permanent set on structural performance of spiral case structures, it is suggested that membrane materials
面向能耗优化的云渲染系统任务调度策略
A Task Scheduling Strategy With Energy Optimization for Cloud Rendering Systems

李谦,卫国,曹莹方,
- , 2016, DOI: 10.7652/xjtuxb201602001
Abstract: 针对云渲染系统中由于渲染节点与任务不匹配调度而带来的能耗浪费问题,提出一种通过任务调度方式来优化系统能耗的策略。为了形式化描述系统的整体能耗,综合考虑节点空闲能耗和任务运行能耗,建立渲染任务能耗模型;以降低系统总体能耗为优化目标,根据渲染任务之间无依赖性的特点,将任务调度序列拆分成子序列,利用模拟退火思想,通过优化子序列任务调度提高节点利用率、减少节点空闲能耗,以此降低系统全局任务的能耗;采用矩阵存储子序列任务的能耗,以空间换时间的方式降低策略的时间复杂度。实验结果表明:该策略在多渲染作业环境中能耗优化效果比先进先出算法提升了43.4%,比能耗感知的调度算法提升了6.7%,能够有效降低云渲染系统的总体能耗,同时具有良好的扩展性,使云渲染系统的能耗效率和整体性能得到提升。
A task scheduling strategy with optimized energy consumption for cloud rendering systems is proposed to solve the problem that the mismatching task scheduling on render nodes causes a great waste of energy consumption. A rendering task energy consumption model is presented to describe formally the overall energy consumption of a system and takes both the idle and the task running energy consumptions of each node into account. The optimization object is to reduce the overall energy consumption of the system, and the strategy divides the task scheduling sequence into subsequences based on the non??dependence characteristic among rendering tasks. The simulated annealing ideology is used to optimize the scheduling of the subsequence tasks, to improve the utilization ratio of the nodes and to reduce the idle energy consumption of nodes so that the energy consumption for the overall system is reduced. Moreover, the strategy adopts a way of space in time to reduce the time complexity by using a matrix to store the energy of subsequence tasks. Experimental results and comparisons with the FIFO algorithm and EMRSA (energy??aware MapReduce scheduling) algorithm in a multi jobs measurement show that the energy optimization performance of the proposed strategy has improved about 43.4% and 6.7%, respectively, that is, the proposed strategy effectively reduces the overall energy consumption for cloud rendering systems. Moreover, the proposed strategy possesses better expansibility. It can be concluded that the proposed strategy can improve the energy efficiency and overall performance of cloud rendering systems
脑中的空间导航系统—placecell和gridcell的发现

中国科学 生命科学 , 2015, DOI: 10.1360/052014-177
Abstract:
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