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Construction of optimal supersaturated designs by the packing method

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Science china Mathematics 2004年第1期47卷 128-143页

作者： fang kaitai GE Gennian liu minqian department of Mathematics Hong Kong Baptist University Hong Kong China Department of Mathematics Zhejiang University Hangzhou 310027 China Department of Statistics Nankai University Tianjin 300071 China

A supersaturated design is essentially a factorial design with the equal occurrence of levels property and no fully aliased factors in which the number of main effects is greater than the number of runs. It has received much recent interest because of its potential in factor screening experiments. A packing design is an important object in combinatorial design theory. In this paper, a strong link between the two apparently unrelated kinds of designs is shown. Several criteria for comparing supersaturated designs are proposed, their properties and connections with other existing criteria are discussed. A combinatorial approach, called the packing method, for constructing optimal supersaturated designs is presented, and properties of the resulting designs are also investigated. Comparisons between the new designs and other existing designs are given, which show that our construction method and the newly constructed designs have good properties.

关键词： Kirkman triple systems, orthogonality, packing design, resolvability, supersaturated design.

A comparison of statistical learning of naturalistic textures between DCNNs and the human visual hierarchy

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Science china(Technological Sciences) 2024年第8期67卷 2310-2318页

作者： LU XinCheng YUAN ZiQi ZHANG YiChi AI HaiLin CHENG SiYuan GE YiRan fang fang CHEN NiHong department of Psychological and Cognitive Sciences Tsinghua UniversityBeijing 100084China IDG/McGovern Institute for Brain Research Tsinghua UniversityBeijing 100084China department of Computer Science and Technology Tsinghua UniversityBeijing 100084China School of Psychological and Cognitive Sciences and Beijing Key Laboratory of Behavior and Mental Health Peking UniversityBeijing 100871China Key Laboratory of Machine Perception(Ministry of Education) Peking UniversityBeijing 100871China Peking-Tsinghua Center for Life Sciences Peking UniversityBeijing 100871China IDG/McGovern Institute for Brain Research Peking UniversityBeijing 100871China State Key Laboratory of Brain and Cognitive Science Institute of PsychologyChinese Academy of SciencesBeijing 100101China

The visual system continuously adapts to the statistical properties of the environment. Existing evidence shows a close resemblance between deep convolutional neural networks(CNNs) and primate visual stream in neural selectivity to naturalistic textures above the primary visual processing stage. This study delves into the mechanisms of perceptual learning in CNNs,focusing on how they assimilate the high-order statistics of natural textures. Our results show that a CNN model achieves a similar performance improvement as humans, as manifested in the learning pattern across different types of high-order image statistics. While L2 was the first stage exhibiting texture selectivity, we found that stages beyond L2 were critically involved in learning. The significant contribution of L4 to learning was manifested both in the modulations of texture-selective responses and in the consequences of training with frozen connection weights. Our findings highlight learning-dependent plasticity in the mid-to-high-level areas of the visual hierarchy. This research introduces an AI-inspired approach for studying learning-induced cortical plasticity, utilizing DCNNs as an experimental framework to formulate testable predictions for empirical brain studies.

关键词： CNN perceptual learning naturalistic texture psychophysics

Uniform design over a convex polyhedron

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Chinese Science Bulletin 1999年第2期44卷 112-114页

作者： fang kaitai , TIAN Guoliang XIE Minyu Hong Kong Baptist university, Kowloon, Hong Kong, china Institute of Applied Mathematics, Chinese Academy of Sciences, Beijing 100080, china Central china Normal university, Wuhan 430070, chinaCorresponding author: Present address: department of Probability and statistics, Peking university, Beijing 100871, china Hong Kong Baptist university Hong Kong China Institute of Applied Mathematics Chinese Academy of Sciences Beijing China Central china Normal university Wuhan China

A new method, called the simplex method, is proposed to generate the uniform design over a convex polyhedron in n-dimensional Euclidean

关键词： convex polyhedron experimental design uniform design.

Optimal mixed-level supersaturated design with general number of runs

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Optimal mixed-level supersaturated design with general numbe...

Finite Groups with Some Bounded Codegrees

2007均匀试验设计学术交流会

作者： Jie Chen,Min-Qian liu department of statistics,School of Mathematical Sciences and LPMC,nankai university,tianjin 300071,china

Supersaturated design has received much interest because of its potentialin factor screening *** studies mainly focused on *** paper considers supersaturated designs with general numbersof *** lower bounds of theχ2 proposed by Yamada and Lin(1999)andE(fNOD)proposed by fang,Lin and liu(2003b)are obtained along with thesu?cient and necessary conditions for achieving them ***-more some construction methods for mixed-level supersaturated designs withgeneral number of runs are proposed.

关键词： Balanced design Coincidence number Orthogonal array Super-saturated design

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1778-1784页

作者： Dong fang YANG Yu ZENG Heng LV School of Mathematics and statistics Southwest UniversityChongqing400715P.R.China department of Mathematics Changshu Institute of TechnologyChangshu215500P.R.China

For a characterχof a finite group G,the number cod(χ) := ∣G:ker(χ)∣/χ(1)is called the codegree ofχ.In this paper,we give a solvability criterion for a finite group G depending on the minimum of the ratioχ(1)^(... 详细信息

关键词： Finite group codegree degree simple group

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Extension of isometries on the unit sphere of l^p (Γ) space

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Science china Mathematics 2010年第4期53卷 1085-1096页

作者： fang XiNian 1,& WANG JianHua 2 1 School of Mathematics and statistics,Nanjing Audit university,Nanjing 210029,china 2 department of Mathematics,Anhui Normal university,Wuhu 241000,china School of Mathematics and statistics Nanjing Audit University Nanjing China department of Mathematics Anhui Normal University Wuhu China

In this paper,we obtain that every isometry from the unit sphere S(l p (Γ)) of l p (Γ) (1 < p < ∞,p≠2) onto the unit sphere S(E) of a Banach space E can be extended to be a (real) linear isometry of l p (Γ) onto ... 详细信息

关键词： isometric extension l p (Γ) space isometry 1-Lipschitz mapping

Construction of column-orthogonal designs for computer experiments

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Science china Mathematics 2011年第12期54卷 2683-2692页

作者： SUN FaSheng PANG fang liu minqian department of statistics KLAS and School of Mathematics and Statistics Northeast Normal University Changchun 130024 China department of statistics School of Mathematical Sciences and LPMC Nankai University Tianjin 300071 China

Latin hypercube design and uniform design are two kinds of most popular space-filling designs for computer experiments. The fact that the run size equals the number of factor levels in a Latin hypercube design makes it difficult to be orthogonal. While for a uniform design, it usually has good space-filling properties, but does not necessarily have small or zero correlations between factors. In this paper, we construct a class of column-orthogonal and nearly column-orthogonal designs for computer experiments by rotating groups of factors of orthogonal arrays, which supplement the designs for computer experiments in terms of various run sizes and numbers of factor levels and are flexible in accommodating various combinations of factors with different numbers of levels. The resulting column-orthogonal designs not only have uniformly spaced levels for each factor but also have uncorrelated estimates of the linear effects in first order models. Further, they are 3-orthogonal if the corresponding orthogonal arrays have strength equal to or greater than three. Along with a large factor-to-run ratio, these newly constructed designs are economical and suitable for screening factors for physical experiments.

关键词： computer experiment Latin hypercube design orthogonal array rotation uniform design

Acute Effects of Exposure to Fine Particulate Matter and Its Constituents on Sex Hormone Among Postmenopausal Women — Beijing, tianjin, and Hebei PLADs, china, 2018–2019

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china CDC weekly 2024年第13期6卷 249-253,I0001-I0004页

作者： Yanlin Tian Jiaonan Wang Jianlong fang Chen Chen Feng Zhao Yi Zhang Peng Du Yawei Li Wanying Shi Yuanyuan liu Enmin Ding Song Tang Xu Yue Xiaoming Shi Chinese Research Academy of Environmental Sciences BeijingChina Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control(AEMPC)Nanjing University of Information Science&TechnologyNanjing CityJiangsu ProvinceChina china CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina department of Epidemiology and Health statistics School of Public HealthCapital Medical Universityand Beijing Municipal Key Laboratory of Clinical EpidemiologyBeijingChina National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina

What is already known on this topic?Exposure to fine particulate matter(PM2.5)was linked to endocrine hormone disruption in the reproductive ***,it was unclear which specific components of PM2.5 were primarily responsible for these *** is added by this report?The study presented the initial epidemiological evidence that brief exposure to PM2.5 can elevate estradiol levels in postmenopausal *** particle components had unique effects,with watersoluble ions and specific inorganic elements like Ag,As,Cd,Hg,Ni,Sb,Se,Sn,and Tl potentially playing significant roles in increasing estradiol *** are the implications for public health practice?The study established that the prevalence of air pollution,along with its specific components,has been recognized as a novel risk factor affecting the balance of sex hormones.

关键词： pollution Particulate primarily

Serum urate is associated with an increased risk of inflammatory bowel disease: A bidirectional Mendelian randomization study

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World Journal of Clinical Cases 2024年第5期12卷 891-902页

作者： Song Zhang Xue fang Le Kang Xiang-Yu Sui Miao liu Yu-Jia Luo Shuo Fu Zhao-Shen Li Sheng-BingZhao Yu Bai department of Gastroenterology Changhai HospitalShanghai 200433China department of Gastroenterology Changhai HospitalSecond Military Medical University/Naval Medical UniversityShanghai 200433China Digestive Endoscopy Center Changhai HospitalNaval/Second Military Medical UniversityShanghai 200433China National Clinical Research Center for Digestive Diseases Shanghai 200433China

BACKGROUND Previous studies have indicated bidirectional associations between urate levels and inflammatory bowel disease(IBD),including ulcerative colitis(UC)and Crohn’s disease(CD).However,it remains unclear whether the observations are causal because of confounding *** To investigate the causal associations between urate levels and IBD using bidirec-tional Mendelian randomization(MR).METHODS Independent genetic variants for urate levels and IBD were selected as instru-mental variables from published genome-wide association studies(GWASs).Summary statistics for instrument-outcome associations were retrieved from three separate databases for IBD(the UK Biobank,the FinnGen database and a large GWAS meta-analysis)and one for urate levels(a large GWAS meta-analysis).MR analyses included the inverse-variance-weighted method,weighted-median estimator,MR-Egger and sensitivity analyses(MR-PRESSO).A meta-analysis was also conducted to merge the data from separate outcome databases using a fixed-effects *** Genetically higher serum urate levels were strongly associated with an increased risk of UC[odds ratio(OR):1.95,95%confidence interval(CI):1.86-2.05]after outlier correction,and the ORs(95%CIs)for IBD and CD were 0.94(95%CI:0.86-1.03)and 0.91(95%CI:0.80-1.04),*** studies have confirmed the positive association between urate levels and ***,genetically predicted IBD was inversely related to urate levels(OR:0.97,95%CI:0.94-0.99).However,no association was observed between genetically influenced UC or CD and urate *** Urate levels might be risk factors for UC,whereas genetically predicted IBD was inversely associated with urate *** findings provide essential new insight for treating and preventing IBD.

关键词： Inflammatory bowel disease Urate levels Antioxidant Mendelian randomization Single nucleotide polymorphism