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Academy of Mathematics and Systems Science, CAS Colloquia & Seminars：PAC方法与计算思维
PAC方法 计算思维 Bloom分类
2023/4/28
计算思维是并列于逻辑思维和实证思维的三大科学思维之一，具有独特的观察世界和解决问题的模式。报告从一个具体例子，即大数据集中最大元素的筛选算法的介绍，讨论了PAC方法背后的计算思维内涵，特别是如何从计算角度看待和认知世界，以及通过计算解决问题的特点。同时讨论了计算思维赋能的三个阶梯，及其与Bloom分类中六个层次的关系.
膨润土在盐溶液作用下化学相容性降低，严重影响膨润土系隔离墙的防渗性能。PB为提高膨润土在盐溶液作用下的防渗性能，通过将2%的聚阴离子纤维素(PAC)与钠化膨润土(CB)直接拌合，制备一种聚合物改良膨润土(PB)。基于改进滤失试验测试不同压力下受CaCl2溶液和蒸馏水作用的PB滤饼渗透系数(分别为kc和kw)。结果表明，随CaCl2浓度增大，PB试样的滤失液体积和滤饼渗透系数增大，但PB试样滤失液体...
Pac-Man-like CRISPR enzymes have potential for disease diagnostics
Pac-Man-like CRISPR enzymes disease diagnostics
2017/7/20
University of California, Berkeley, researchers have described 10 new CRISPR enzymes that, once activated, behave like Pac-Man to chew up RNA in a way that could be used as sensitive detectors of infe...
Enhanced Coagulation on Micro-Polluted Raw Water by Attapulgite Clay and PAC Combination Process
Attapulgite Clay Enhanced Coagulation Micro-Polluted Raw Water Poly Aluminum Chloride (PAC)
2011/11/15
Attapulgite clay and Poly aluminum chloride (PAC) combination process was adopted for enhanced coagulation on micro-polluted raw water, TOC and NH3-N served as water quality indexes. Results showed th...
PAC-Bayesian aggregation and multi-armed bandits
PAC-Bayesian aggregation multi-armed bandits
2010/11/22
This habilitation thesis presents several contributions to (1) the PAC-Bayesian analysis of statistical learning, (2) the three aggregation problems: given d functions, how to predict as well as (i) ...
Pac-bayesian bounds for sparse regression estimation with exponential weights
Sparsity Oracle Inequality High-dimensional Regression
2010/12/6
We consider the sparse regression model where the number of parameters p is larger than the sample size n. The difficulty when considering high-dimensional problems is to propose estimators achieving ...
研究了联合硅藻土与聚合氯化铝（PAC）强化混凝对原水中藻类、溶解性有机物以及重金属离子的去除效果。结果表明，硅藻土的投加可以有效地改善絮体的沉降性能，增强藻类的混凝沉淀去除效率，PAC投加量为30 mg/L时，投加0.1 g/L硅藻土，叶绿素a去除率由82.5%提高到95.9%。该强化混凝过程使原水中溶解性有机物特别是大分子有机物和重金属离子的去除率有所上升。PAC投加量为30 mg/L，硅藻土投...
采用XRD和显微镜分析技术研究了高浴比淤浆法制备聚阴离子纤维素过程中, NaOH、KOH及其混合碱化体系对纤维素润胀度及结晶度的影响, 借助1H NMR方法分析了产物的取代度及取代基在葡萄糖环基C2、C3和C6位分布的均匀性. 通过泥浆实验研究了产品在高电解质含量中的高温滤失性能. 结果表明, 在相同摩尔浓度条件下, 棉纤维润胀度变化规律是: NaOH/KOH(摩尔比, 9∶1)>NaOH>NaO...
PAC investigation of qudropole interaction in nano-soft magnetic material Fe73.5Cu1Nb3Si13.5B9
PAC Kev-ISOL Fe73.5Cu1Nb3Si13.5B9
2009/8/14
The quadrupole interaction in nano-soft magnetic material Fe73.5Cu1Nb3Si13.5B9 has been studied by perturbed angular correlation using 62Zn probe nuclei from the ISOL radioactive nuclear beam facility...
PAC与粘土矿物混凝去除颤藻及残余铝形态研究
浊度和叶绿素a 去除率 悬浮态铝溶解态铝
2012/3/13
研究了PAC与不同粒径的天然粘土矿物复合混凝去除给水中的颤藻。结果表明，两者复合除藻效果显著优于单加PAC。当PAC浓度为12 mg/L，矿物浓度为24 mg/L，粒径为160目时，除藻效果最好，浊度和叶绿素a去除率分别为98.2%和100%。两者复合后PAC形态含量都发生了变化，悬浮态铝含量相对增加，溶解态铝含量相对减少，总残余铝量减小。
猪PAC克隆的微卫星DNA分离研究Studies of Microsatellite Isolation from Porcine PAC Clone
猪 PAC克隆 微卫星DNA
2008/1/16
摘要利用(CA)8核心序列，设计锚定引物，采用直接测序法，从单个猪PAC克隆中分离到一个新微卫星DNA。根据该微卫星DNA的侧翼序列，设计了专一引物，在8个猪种40个个体中检测到3个等位基因，片段长度分别为305 bp、307 bp和309 bp。3种等位基因纯合子个体的PCR产物序列分析表明，这3种等位基因分别有12、13和14次CA双核苷酸重复。
Abstract:A novel micro...
变形链球菌表面蛋白抗原(PAc)的A区和P区融合共表达、纯化及抗原性研究
变形链球菌 PAc 重组蛋白 龋齿
2012/11/12
变形链球菌（Streptococcus mutans）是引起人类龋齿的主要致病菌,其表面蛋白(PAc)是龋齿疫苗研究的主要对象.在该研究中,变形链球菌pac基因的功能A区和P区经PCR扩增后,以连接链Gly4SerGly4连接,并克隆至pET32a质粒中构建成pET32a-A-P重组表达载体,经IPTG诱导表达后,表达产物A-P重组蛋白(rA-P蛋白)经饱和硫酸铵沉淀、镍亲和层析、疏水层析...
Implantation of 111In in the Heusler Alloys Pd2MnZ (Z=Sn,Sb,Ge,In) Following Heavy Ion Nuclear Reactions: Measurement of Magnetic Hyperfine Field using PAC Spectroscopy
Magnetic Hyperfine Field PAC Spectroscopy the Heusler Alloys Pd2MnZ
2010/10/15
Ion implantation of the recoil 111In nuclei following heavy ion nuclear reactions 108Pd(7Li,4n)111In and 108Pd(6Li,3n)111In has been used to implant 111In probes in the Heusler alloys Pd2MnZ(Z=Sn,Sb,G...