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Science China(Technological Sciences) 2008年第6期51卷 656-673页

作者： ZHAO GuangHui CHEN BaiXiao zhu Shouping National Key Lab for Radar Signal Processing Xidian UniversityXi’an 710071China

A new direction synthetic method for monostatic multiple input multiple output (MIMO) radar is presented based on synthetic impulse and aperture radar (SIAR) system. Concerned with the monostatic MIMO radar which simultaneously emits orthogonal signals with multi-carrier-frequency and possesses sparsely distributed transmitting and receiving arrays with respective location, as well as the situation for the presence of multipath propagation in the low flying target’s echo, the method integrates the aperture of the transmitting arrays with the receiving arrays to form the digital beam-forming (DBF) in azimuth and elevation dimensions. And a study has been made of planar general MUSIC algorithm based on decorrelating the multipath signals of multi-carrier-frequency MIMO radar. Through compensat-ing the phase delay of both the transmitting and the receiving arrays and synthe-sizing the transmitting beam in two dimensions at the receiver, the angular resolu-tion and measurement accuracy are improved and the computational complexity is reduced after transforming the three-dimensional (3D) parameter estimation prob-lem into a two-dimensional (2D) one. Finally, the Cramer-Rao Bounds (CRBs) of DOA estimation for azimuth and elevation is put forward with the exsiting multipath propagation. Results of computer simulation demonstrate the validity of the new method.

关键词： SIAR monostatic MIMO radar multipath propagation super resolution general MUSIC algorithm Cramer-Rao Bounds

One-dimensional horizontal infiltration experiment for determining permeability coefficient of loamy sand

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Journal of Arid Land 2017年第1期9卷 27-37页

作者： HU Shunjun zhu Hai CHEN Yongbao State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China University of Chinese Academy of Sciences Beijing 100049 China Central South Institute of Metallurgical Geology Yichang 443003 China

A knowledge of soil permeability is essential to evaluate hydrologic characteristics of soil, such as water storage and water movement, and soil permeability coefficient is an important parameter that reflects soil permeability. In order to confirm the acceptability of the one-dimensional horizontal infiltration method（one-D method） for simultaneously determining both the saturated and unsaturated permeability coefficients of loamy sand, we first measured the cumulative infiltration and the wetting front distance under various infiltration heads through a series of one-dimensional horizontal infiltration experiments, and then analyzed the relationships of the cumulative horizontal infiltration with the wetting front distance and the square root of infiltration time. We finally compared the permeability results from Gardner model based on the one-D method with the results from other two commonly-used methods（i.e., constant head method and van Genuchten model） to evaluate the acceptability and applicability of the one-D method. The results showed that there was a robust linear relationship between the cumulative horizontal infiltration and the wetting front distance, suggesting that it is more appropriate to take the soil moisture content after infiltration in the entire wetted zone as the average soil moisture content than as the saturated soil moisture content. The results also showed that there was a robust linear relationship between the cumulative horizontal infiltration and the square root of infiltration time, suggesting that the Philip infiltration formula can better reflect the characteristics of cumulative horizontal infiltration under different infiltration heads. The following two facts indicate that it is feasible to use the one-D method for simultaneously determining the saturated and unsaturated permeability coefficients of loamy sand. First, the saturated permeability coefficient（prescribed in the Gardner model） of loamy sand obtained from the one-D me

关键词： permeability coefficient one-dimensional horizontal infiltration cumulative horizontal infiltration wetting front distance Philip infiltration formula Gardner model

Gut Bacterial and Lactobacilli Communities of Weaning Piglets in Response to Mannan Oligosaccharide and Sugar Beet Pulp In vitro Fermentation

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Journal of Integrative Agriculture 2012年第1期11卷 122-133页

作者： HANG Su-qin zhu Wei-yun Laboratory of Gastrointestinal Microbiology Nanjing Agricultural UniversityNanjing 210095P.R.China

Microbiota in the gastrointestinal tract （GIT） of piglets during weaning transition can experience a sharp change which could result in growth reduction and diarrhea of weaned piglets. Dietary manipulations can play an important role in attenuating such changes caused by weaning stress. Therefore, ileal and colonic contents of weaned piglets were used as inocula, mannan oligosaccharide （MOS） or sugar beet pulp （SBP） was supplied as single energy sources to investigate effects of MOS or SBP on the shifts of gastro-intestinal microflora and lactobacilli populations. The universal bacteria- and lactobacilli-specific PCR/denaturing gradient gel electrophoresis （DGGE）, cloning and sequencing techniques were used. DGGE profiles of the universal bacteria showed that great changes were found in the position, numbers and intensity of dominant bands after fermentation. The similarity of bacterial community between ileum and colon was increased to 85-97% by MOS or SBP treatment after fermentation from the similarity with 20% before fermentation. MOS treatment significantly increased the bacterial diversity and band number in both ileal and colonic fermentation （P〈0.05）. SBP treatment significantly increased the bacterial diversity and band number in colon （P〈0.05）. It implies that some species were enriched by the addition of MOS or SBP to increase the similarity and diversity of bacterial community in weaned piglets. Five specific bands appearing in MOS or SBP treatment group after fermentation were cloned and sequenced, the changes of species related to Prevotella and Ruminococcus were observed. Two bands related to uncultured bacterium with 98% similarity were detected by MOS or SBP treatment. However, there were no effects on the similarity, diversity index and lactobacilli species revealed by MOS or SBP treatment. These results imply that MOS or SBP could have beneficial effects on the weaning piglets by stablizing microbiota in the GIT microflora.

关键词： mannan oligosaccharide (MOS) sugar beet pulp (SBP) bacterial communities lactobacilli weaning piglets

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长期磷肥处理农田黑土细菌群落特征

应用生态学报 2008年第7期19卷 1567-1573页

作者：白震张明张旭东朱平彭畅中国科学院沈阳应用生态研究所陆地生态过程重点实验室辽宁大学生命科学学院沈阳110036 吉林省农业科学院中国农业科技东北创新中心长春130033

研究了公主岭国家黑土长期定位站不同施肥处理(对照、磷、氮-磷、氮-磷-钾、有机肥-磷、有机肥-氮-磷、有机肥-氮-磷-钾等)土壤基本理化性质及细菌群落特征.结果表明:有机肥处理土壤有机质(OM)、总氮(TN)、有效磷(AP)、碱解氮(AN)、速效... 详细信息

研究了公主岭国家黑土长期定位站不同施肥处理(对照、磷、氮-磷、氮-磷-钾、有机肥-磷、有机肥-氮-磷、有机肥-氮-磷-钾等)土壤基本理化性质及细菌群落特征.结果表明:有机肥处理土壤有机质(OM)、总氮(TN)、有效磷(AP)、碱解氮(AN)、速效钾(AK)等养分含量显著增加,而单施化肥各处理OM、AN含量无明显变化.与未施肥对照处理相比,有机肥-氮-磷配施与有机肥-氮-磷-钾配施处理总细菌磷脂脂肪酸分别增加34%和62%,G+菌磷脂脂肪酸分别增加58%和74%,G-菌磷脂脂肪酸分别增加64%和69%.各化肥处理细菌脂肪酸含量均有所下降,以磷处理最低.除G+菌磷脂脂肪酸外(有机肥-磷配施显著大于氮-磷-钾肥配施),氮-磷肥配施、氮-磷-钾肥配施与有机肥-磷肥配施三者间细菌脂肪酸含量无显著差异.相关分析表明,各细菌磷脂脂肪酸与OM、AP、AN、AK、NO3--N含量呈极显著相关.

关键词：磷脂脂肪酸细菌黑土磷肥农家肥

Ⅱ~Ⅲ期胃癌根治术中淋巴结清扫数目与远期复发、死亡的关系探讨

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罕少疾病杂志 2025年第1期32卷 119-120,123页

作者：岑磊磊朱桂华南通市通州区中医院江苏南通226300

目的探讨Ⅱ~Ⅲ期胃癌患者根治术中淋巴结清扫数目与远期复发、死亡的关系。方法回顾性分析2018年12月至2020年12月期间本院收治的186例Ⅱ~Ⅲ期胃癌并行根治术患者的临床资料,并对患者随访至2022年12月。根据国际抗癌联盟要求和术中淋... 详细信息

目的探讨Ⅱ~Ⅲ期胃癌患者根治术中淋巴结清扫数目与远期复发、死亡的关系。方法回顾性分析2018年12月至2020年12月期间本院收治的186例Ⅱ~Ⅲ期胃癌并行根治术患者的临床资料,并对患者随访至2022年12月。根据国际抗癌联盟要求和术中淋巴结清扫数目分为≥25枚组(88例)和15~25枚组(98例),在控制性别、年龄、肿瘤大小、肿瘤部位等变量的前提下,采用COX风险回归分析淋巴结清扫数目与胃癌患者远期复发和死亡的关系。结果随访2年后,186例患者中胃癌复发61例,死亡38例,复发率和死亡率分别为32.80%和20.43%。单因素分析显示,≥25枚组患者胃癌的复发率为25.00%低于15~25枚组的39.80%(P<0.05);≥25枚组患者的死亡率为12.50%低于15~25枚组的27.55%(P<0.05);COX风险回归分析显示,淋巴结清扫数目是胃癌患者远期复发和死亡的危险因素(HR=2.776、1.669,P<0.05)。结论 Ⅱ~Ⅲ期胃癌患者根治术中淋巴结清扫数目与远期复发、死亡显著相关,且淋巴结清扫数目≥25枚患者胃癌远期复发、死亡的风险较低。

关键词：胃癌根治术淋巴结清扫数目远期复发死亡病理分期

维普期刊数据库博看期刊

Preparation of AgBiVMoO/γ-Al2O3 Catalysts for the Partial Oxidation of Propane to Acrylic Acid by the Mixed Sol Method

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Journal of Energy Chemistry 2002年第Z2期 127-130页

作者： Hongbo Li, Jianhua Tong, Hongjuan zhu, Baichun zhu, ping Yang, Weishen YangState Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China

A novel mixed sol method was developed for the preparation of supported catalysts. Analyses by means of XRD and BET show that a 40%AgBiVMoO/γ-Al2O3 catalyst prepared by this method possessed high specific surface area and high dispersion of the active phase. As a result, high acrylic acid selectivity of 8.5% was obtained when the catalyst was used in the reaction of propane partial oxidation to acrylic acid in a fixed-bed reactor.

关键词： 

New Fractal Evidence of Pacific Plate Subduction in the Late Mesozoic, Great Xing’an Range, Northeast China

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Journal of Earth Science 2019年第5期30卷 1031-1040页

作者： pingping zhu Qiuming Cheng Guoxiong Chen School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China

Late Mesozoic granitoids are widespread in the Great Xing’an Range(GXR), which is part of a large igneous province in eastern China. The geodynamic setting of the Late Mesozoic granitoids is still debated, and there have been two dominant models proposed, subduction and thermal erosion. This study discusses the geodynamic mechanisms from a new perspective on ages of the granitoids and fractal dimensions of their shape. Our results show that granitoids become gradually older from South GXR to North GXR to Erguna Block(EB) in the Jurassic, and opposite in the Cretaceous. The fractal dimensions of the Perimeter-area model(DAP) exhibit the same features. The values of DAP are smaller from South GXR(0.673 1) to North GXR(0.628 0) to EB(0.607 9) in the Jurassic, and larger from South GXR(0.609 6) to North GXR(0.630 2) to EB(0.639 9) in the Cretaceous. This implies that the geometrical irregularities of the granitoids are shaped by subduction rather than thermal erosion. These spatial variations could be best explained by the subduction of the Pacific Plate and consequent granitoid magmatism in the Late Mesozoic, thus providing a new fractal evidence for Pacific Plate subduction mechanism and opening a new possibility method for studing plate movement.

关键词： granitoids Late Mesozoic fractal dimension Pacific subduction Great Xing’an Range Northeast China geochemistry mathematical geology

Tensor semantic model for an audio classification system

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Science China(Information Sciences) 2013年第6期56卷 106-114页

作者： XING Ling MA Qiang zhu Min School of Information Engineering Southwest University of Science and Technology

Audio resources are a very important part of multimedia *** classification effect of audio is directly related to the service mode of personal resource management *** present,vector features have been widely used in audio classification ***,some semantic correlations among different audio information can not be completely expressed by simple vector *** are multidimensional matrices,and their mathematical expansion and application can express multi-semantic *** tensor uniform content locator(TUCL) is proposed as a means of expressing the semantic information of audio,and a three-order tensor semantic space is constructed according to the semantic *** semantic dispersion(TSD) can aggregate some audio resources with the same semantics and,at the same time,its automatic classification can be accomplished by calculating the *** order to effectively utilize TSD classification information,a radial basis function tensor neural network(RBFTNN) is constructed and used to train an intelligent learning *** results show that the tensor model can significantly improve the classification precision under multi-semantic classification requests within an information resource management system.

关键词： audio classification tensor semantic dispersion tensor uniform content locator

Study on the critical diameter of the subway tunnel based on the pressure variation

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Science China(Technological Sciences) 2014年第10期57卷 2037-2043页

作者： SUN ZhenXu YANG GuoWei zhu Lan Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of Mechanics Chinese Academy of Sciences Beijing Rail and Transit Design & Research Institute CO.LTD

When the subway train operates at a speed higher than 100 km/h,the corresponding aerodynamic issue becomes *** meet the future requirement for the speedup of subway trains,a research on the critical diameters of the subway tunnel for trains operating at 120 and 140 km/h has been performed based on passengers’aural discomfort caused by rail tunnel pressure variation.A three-dimensional computational fluid dynamic approach has been adopted for ***,trains with different airtight indices are considered and the pressure variations inside and outside the trains are both under *** on the corresponding criteria for different airtight indices,critical tunnel diameters for trains running at different speeds have been *** study would aid in the tunnel section design for future high-speed subway trains.

关键词： tunnel pressure waves airtight index aural discomfort blockage ratio

Comparison and development of machine learning for thalidomideinduced peripheral neuropathy prediction of refractory Crohn’s disease in Chinese population

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World Journal of Gastroenterology 2023年第24期29卷 3855-3870页

作者： Jing Mao Kang Chao Fu-Lin Jiang Xiao-ping Ye Ting Yang Pan Li Xia zhu Pin-Jin Hu Bai-Jun Zhou Min Huang Xiang Gao Xue-Ding Wang Institute of Clinical Pharmacology School of Pharmaceutical SciencesSun Yat-sen UniversityGuangzhou 510006Guangdong ProvinceChina Guangdong Provincial Key Laboratory of New Drug Design and Evaluation Sun Yat-sen UniversityGuangzhou 510006Guangdong ProvinceChina Department of Gastroenterology The Sixth Affiliated HospitalSun Yat-sen UniversityGuangzhou 510006Guangdong ProvinceChina Department of Pharmacy Guangdong Women and Children HospitalGuangzhou 510000Guangdong ProvinceChina

BACKGROUND Thalidomide is an effective treatment for refractory Crohn’s disease(CD).However,thalidomide-induced peripheral neuropathy(TiPN),which has a large individual variation,is a major cause of treatment *** is rarely predictable and recognized,especially in *** is necessary to develop a risk model to predict TiPN *** To develop and compare a predictive model of TiPN using machine learning based on comprehensive clinical and genetic *** A retrospective cohort of 164 CD patients from January 2016 to June 2022 was used to establish the *** National Cancer Institute Common Toxicity Criteria Sensory Scale(version 4.0)was used to assess *** 18 clinical features and 150 genetic variables,five predictive models were established and evaluated by the confusion matrix receiver operating characteristic curve(AUROC),area under the precision-recall curve(AUPRC),specificity,sensitivity(recall rate),precision,accuracy,and F1 *** The top-ranking five risk variables associated with TiPN were interleukin-12 rs1353248[P=0.0004,odds ratio(OR):8.983,95%confidence interval(CI):2.497-30.90],dose(mg/d,P=0.002),brainderived neurotrophic factor(BDNF)rs2030324(P=0.001,OR:3.164,95%CI:1.561-6.434),BDNF rs6265(P=0.001,OR:3.150,95%CI:1.546-6.073)and BDNF rs11030104(P=0.001,OR:3.091,95%CI:1.525-5.960).In the training set,gradient boosting decision tree(GBDT),extremely random trees(ET),random forest,logistic regression and extreme gradient boosting(XGBoost)obtained AUROC values>0.90 and AUPRC>*** these models,XGBoost and GBDT obtained the first two highest AUROC(0.90 and 1),AUPRC(0.98 and 1),accuracy(0.96 and 0.98),precision(0.90 and 0.95),F1 score(0.95 and 0.98),specificity(0.94 and 0.97),and sensitivity(1).In the validation set,XGBoost algorithm exhibited the best predictive performance with the highest specificity(0.857),accuracy(0.818),AUPRC(0.86)and AUROC(0.89).ET and GBDT obtained the highest sensitivity(1)and F1 score(0.8)

关键词： Thalidomide-induced peripheral neuropathy Refractory Crohn’s disease Neurotoxicity prediction models Machine learning Gene polymorphisms