检索结果-南通市图书馆

HybridTune: Spatio-Temporal Performance Data Correlation for Performance Diagnosis of Big Data Systems

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2019年第6期34卷 1167-1184页

作者： Rui Ren Jiechao Cheng xi-Wen He Lei Wang Jian-Feng Zhan Wan-Ling Gao Chun-Jie Luo Institute of Computing Technology Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Computing National University of SingaporeSingapore 117417Singapore

With tremendous growing interests in Big Data, the performance improvement of Big Data systems becomes more and more important. Among many steps, the first one is to analyze and diagnose performance bottlenecks of the Big Data systems. Currently, there are two major solutions. One is the pure data-driven diagnosis approach, which may be very time-consuming;the other is the rule-based analysis method, which usually requires prior knowledge. For Big Data applications like Spark workloads, we observe that the tasks in the same stages normally execute the same or similar codes on each data partition. On basis of the stage similarity and distributed characteristics of Big Data systems, we analyze the behaviors of the Big Data applications in terms of both system and micro-architectural metrics of each stage. Furthermore, for different performance problems, we propose a hybrid approach that combines prior rules and machine learning algorithms to detect performance anomalies, such as straggler tasks, task assignment imbalance, data skew, abnormal nodes and outlier metrics. Following this methodology, we design and implement a lightweight, extensible tool, named HybridTune, and measure the overhead and anomaly detection effectiveness of HybridTune using the BigDataBench benchmarks. Our experiments show that the overhead of HybridTune is only 5%, and the accuracy of outlier detection algorithm reaches up to 93%. Finally, we report several use cases diagnosing Spark and Hadoop workloads using BigDataBench, which demonstrates the potential use of HybridTune.

关键词： Big Data system spatio-temporal correlation rule-based diagnosis machine learning

Enhanced hydrothermal stability of Cu-SAPO-34 with an ultrathin TiO_(2)coated by atomic layer deposition for NH3-SCR

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2022年第10期65卷 2325-2336页

作者： TIAN HeYuan xi WenChang ZHANG YiBo SUN LiWei LIU Peng WU Fan YANG Guo GUO Feng YANG xiangGuang State Key Laboratory of Rare Earth Resource Utilization Jilin Province Key Laboratory of Green Chemistry and ProcessChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China College of Materials Sciences and Engineering Henan Institute of TechnologyXinxiang 453000China Ganjiang Innovation Academy Chinese Academy of SciencesGanjiang 341000China

Reducing pollution and carbon emissions is an important step toward peaking CO_(2)emissions before 2030 and reaching carbon neutrality before 2060,and heavy diesel vehicle pollution,particularly nitrogen oxides(NOx)emissions,is an essential ***-34 is a CHA-type small pore molecular sieve with excellent ammonia(NH_(3))selective catalytic reduction(NH_(3)-SCR)catalytic activity,but it cannot be stored or applied because of severe degradation caused by low-temperature hydrothermal *** improve the hydrothermal stability,TiO_(2)was coated on the surface of Cu-SAPO-34 by the ALD method to form a uniform *** this ultrathin TiO_(2)nanolayer has little effect on NH_(3)-SCR catalytic activity of Cu-SAPO-34,the resistance to low-temperature hydrothermal aging in liquid water at 80℃for 24 h has greatly been improved.A study carried out by SEM,XRD,NH_(3)-TPD,and EPR,showed that the ultra-thin TiO_(2)nanolayers were covered uniformly and hydrolysis of frameworks silicon and the migration of Cu^(2+)was *** method has some implications for the future preparation of highly robust Cu-SAPO-34 catalysts for industrial *** research could inspire the development of highly robust CuSAPO-34 catalysts to control the NOx emissions from diesel engines.

关键词： selective catalytic reduction chabazite zeolite catalyst Cu-SAPO-34 low-temperature hydrothermal stability atomic layer deposition

Escaping from Strange Sets in Discontinuous Circle Map

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1996年第4期13卷 249-252页

作者： WANG Bing-hong HE Da-ren JI xi-ping GUAN Shan SUN Jian-gang QU Shi-xian Department of Modern Physics University of Science and Technology of ChinaHefei 230026 Department of Physics Northwestern UniversityXi'an 710069 Department of Basic Courses Xi'an Petroleum InstituteXian 710061

The leakage of iterations from chaotic attractor near crisis due to dynamical inter-action between discontinuity and noninvertibility has been *** scaling law of the mean life time is derived *** numerical result show... 详细信息

关键词： attractor chaotic scaling

The History of Saffron in China:From Its Origin to Applications

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Medicine and Culture 2021年第4期4卷 228-234页

作者： Rong-Chen Dai Wan Najbah Nik Nabil Hong-xi Xu School of Pharmacy Shanghai University of Traditional Chinese MedicineShanghai 201203China Pharmaceutical Services Program Ministry of HealthSelangor 46200Malaysia Engineering Research Center of Shanghai Colleges for TCM New Drug Discovery Shanghai 201203China

Saffron(Stigma Croci)is an autumn-flowering perennial plant,and its use has a history of over 3500 *** has often been considered as the costliest medicinal plant,a premium spice,and the best dye with a golden yellowish *** currently produces the finest quality saffron and dominates its global production(>90%).Other countries such as Australia,Canada,the USA,China,and some countries in Central Africa,produce saffron at a lower *** China,saffron is celebrated as“red gold”owing to the red stigmas of the flower and its price,which is comparable to the price of *** has been one of the most attractive traditional Chinese medicine(TCM)herbs in the Zhong Guo Yao Dian(《中国药典》Chinese Pharmacopoeia)since its inclusion in the 2005 *** earliest use of saffron in TCM was recorded in the Ben Cao Shi Yi(《本草拾遗》Supplement to Materia Medica)written during the Tang dynasty(741 A.D.).However,saffron grown in inland China has been widely mistaken as originating from *** is because its Chinese name begins with“xi”or“Zang,”which sounds similar to its Tibetan name(“xi Zang”).In this review,we clarify the origin of saffron and its introduction to China and summarize its various applications.

关键词： Cosmetics industry history origin perfumery saffron spice traditional Chinese medicine

Highly dispersive tetrahedral vanadium species on pure silica ZSM-12 zeolite boosting the selective oxidation of cyclohexane into cyclohexanone

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第7期67卷 2206-2214页

作者： Menglin xie Ting Li Chao Wu xiaoling Liu Jinling Ni Siqin Yao Yu Zhou Shibo xi Jun Wang State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China Institute of Sustainability for Chemicals Energy and Environment(ISCE2)Agency for ScienceTechnology and Research(A*STAR)Singapore 627833Republic of Singapore College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

The selective oxidation of cyclohexane is a promising green route for the production of KA oil(cyclohexanol and cyclohexanone),but remains a huge challenge to design high-performing heterogeneous catalysts under mild ***,a pure silica ZSM-12(MTW topology)zeolite was applied as the support to immobilize highly dispersive tetrahedrally coordinated vanadium(V)species and the constructed catalyst 1%V/SZ-12 exhibited high efficiency in the fast and selective oxidation of cyclohexane into cyclohexanone with H_(2)O_(2).The reaction completed within 30 s,affording the selectivity of 99%towards cyclohexanone and the extremely high turnover frequency(TOF)of 5,891 h^(-1).1%V/SZ-12 was facilely reused with stable activity and feasibly extended to the oxidation of various cyclohexane *** one-dimensional 12-membered ring microchannels contributed to the formation and accessibility of tetrahedrally coordinated high valent V5+species as the robust active centers,which activated H_(2)O_(2) to generate V–O–O·,the active oxygen species for the electrophilic attack on cyclohexane to produce cyclohexanone as the sole product.

关键词： zeolite metal doping cyclohexane oxidation heterogeneous catalysis

同方期刊数据库

Electromagnetic Technology for Vacuum Metrology in the Typical Development of a Metrological-Grade Spinning Rotor Gauge

在线全文

学校读者我要写书评

暂无评论

Electromagnetic Science 2023年第3期1卷 88-99页

作者： Detian Li Meiru Guo Zhenhua xi Huzhong Zhang Bowen Li Science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of PhysicsLanzhou 730000China

As the most precise viscous vacuum gauge,the spinning rotor gauge is widely used in the aerospace,nuclear,semiconductor,and other fields because of its excellent accuracy and chemical ***,a metrological-grade spinning rotor vacuum gauge is developed,and its performance is *** can be used for international comparison of vacuum standards and construction of national vacuum measurement traceability and transmission *** paper presents the design of a single-degree-of-freedom permanent magnet-biased rotor suspension system,a high-speed rotary stepper drive system,a rotational angular velocity determination system,a lateral damping system,and a transducer in *** change in residual drag is less than 0.49%after 50 minutes of *** is good consistency and linearity in the range of 9.1727×10^(−5)Pa to 1.2081 Pa.

关键词： Magnetically levitated rotor Vacuum metrology Transfer standard Viscous vacuum gauge

Regulatory mechanisms of rapeseed petal color formation:Current research status and future perspectives

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Oil Crop Science 2022年第4期7卷 174-179页

作者： Shijun Li Tao Chang xi Li Zechuan Peng Chunyun Guan Mei Guan National Oil Crops Improvement Center in Hunan Department of AgronomyHunan Agricultural UniversityChangsha410128China

Flower color,an important rapeseed character,has great practical value and research *** has become an area of intensive research in recent *** paper summarizes the latest research progress on rape flower color in terms of variety,source,pigment composition,formation mechanism,and ***,it provides an overview of rape flower color breeding and omics.

关键词： Rape Flower color Carotenoids Flavonoids Omics

Cannabinoid CB1 receptors are expressed in a subset of dopamine neurons and underlie cannabinoid modulation of DA release and DA-related behavior in mice

在线全文

学校读者我要写书评

暂无评论

中国药理学与毒理学杂志 2023年第7期37卷 535-536页

作者： HAN xiao WU Ning xi Zhengxiong LI Jin Beijing Key Laboratory of Neuropsychopharmacology State Key Laboratory of Toxicology and Medical Countermeasures Beijing Institute of Pharmacology and Toxicology Addiction Biology Unit Molecular Targets and Medications Discovery Branch Intramural Research Program National Institute on Drug Abuse

OBJECTIVE Cannabinoids modulate dopamine(DA) transmission and DA-related behavior,which has been thought to be mediated initially by activation of cannabinoid CB1 receptors(CB1Rs) on GABA neurons. However, the cellular and receptor mechanisms underlying cannabinoids′ psychoactive effects are not fully understood. The present study is to explore the possible expression character of CB1Rs and elucidated the underlying mechanism of them. METHODS We took advantage of RNAscope in situ hybridization(ISH)assays and triple-staining assays to detect the CB1Rexpressing neurons. We established an optical intracranial self-stimulation(OICSS) behavioral model by using optogenetics to study dopaminergic reinforcement *** and synthetic cannabinoids were used to study the function of CB1Rs. Conditional genetic depletion of CB1Rs and behavioral assay were performed to study the modulatory role of CB1Rs in DA-related *** We found that CB1Rs are also expressed in a subset of DA neurons and functionally underlie cannabinoid action in male and female mice. ISH assays demonstrated CB1 mRNA in tyrosine hydroxylase(TH)-positive DA neurons in the ventral tegmental area(VTA) and glutamate decarboxylase 1(GAD1)-positive GABA neurons. The CB1R expressing DA neurons were located mainly in the middle portion of the VTA with the number of CB1-TH colocalization progressively decreasing from the medial to the lateral VTA. Triple-staining assays indicated CB1R mRNA colocalization with both TH and vesicular glutamate transporter 2(VgluT2, a glutamate neuronal marker) in the medial VTA close to the midline of the brain. Optogenetic activation of this population of DA neurons was rewarding as assessed by OICSS.D9-tetrahydrocannabinol(D9-THC) or ACEA(a selective CB1R agonist) dose-dependently inhibited optical intracranial self-stimulation in DAT-Cre control mice, but not in conditional knockout mice with the CB1R gene absent in DA neurons. In addition, deletion of CB1Rs from

关键词：

Tongmai Yangxin Pill combined with metoprolol or metoprolol alone for the treatment of symptomatic premature ventricular complex:a multicenter,randomized,parallel-controlled clinical study

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Geriatric Cardiology 2022年第4期19卷 284-291页

作者： Li-Jun LIU Guo-Hua ZHU Hong-Yu LUO xi-Peng SUN Jing LI Qi HUA Department of Cardiology Xuanwu Hospital Capital Medical UniversityBeijingChina Department of Geriatrics Xuanwu Hospital Capital Medical UniversityBeijingChina

OBJECTIVE To investigate the effects of Tongmai Yangxin Pill(TMYXP)combined with metoprolol tartrate or metoprolol alone for the treatment of premature ventricular complex(PVC)in patients with symptomatic frequent *** A total of 584 patients with symptomatic frequent PVC were randomly assigned(in a 1:1 ratio)into two groups:study group[n=292,TMYXP(40 pills twice/day,orally)combined with metoprolol tartrate(25 mg twice/day,orally)]and control group[n=292,metoprolol tartrate(25 mg twice/day,orally)plus placebo pill(40 pills twice/day,orally)].The total treatment period was eight *** After eight weeks of treatment,the total effective rate of reduction of PVC in the study group and the control group were 76.4%and 51.4%,respectively(P<0.001).TMYXP combined with metoprolol tartrate demonstrated a significantly greater reduction of the frequency of PVCs compared with the metoprolol tartrate alone(−4537 times/24 h vs.−3013 times/24 h,P<0.001).The study group also showed a better result compared with the control group with respect to PVC related *** terms of New York Heart Association classification improvement,the total effective rates were 21.9%in the study group and 12.4%in the control group(P<0.05).Both the study group and the control group exhibited improvements in echocardiographic *** ventricular ejection fraction was significantly improved in the study group compared with the control group(P<0.05).There was no significant difference in the incidence of adverse events between the two *** Compared with metoprolol tartrate alone,TMYXP combined with metoprolol tartrate could more effectively reduce the frequency of PVC and alleviated PVC related symptoms,and improve cardiac function in patients with symptomatic PVC.

关键词： treatment alone complex